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SAGIRAJU, Sruthi. "Liquid biopsy provides complementary information to tissue biopsies for molecular classification of DLBCL patients." Doctoral thesis, Università del Piemonte Orientale, 2022. http://hdl.handle.net/11579/144258.
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Diffuse large B-cell lymphoma is a molecular heterogeneous disease with a variable clinical course and prognosis. Recent studies have identified different molecular clusters on tissue biopsy. Liquid biopsy is a non-invasive tool that allows the collection of circulating tumor DNA (ctDNA) shed by apoptotic tumor cells potentially deriving from all the different sites of the lymphoma. This may provide an integrative source of tumor DNA for DLBCL genotyping. The aims of the study are: i) to identify new prognostic molecular markers on ctDNA and on lymph node biopsy (LN); and ii) to compare the DLBCL molecular clusters between the LN and the ctDNA. The mutational profiling performed in 77 DLBCL patients, through a NGS approach, allows to identify at least one somatic non-synonymous mutation in 92.2% of patients in the LN biopsy, and in 87.0% in the ctDNA. Mutation analysis of different compartments allowed to identify mutations with potential clinical impact: GRHPR (p=0.035) and SGK1 (p=0.039) mutations in ctDNA, and MYC mutations in LN (p=0.021) were associated with a shorter PFS. Moreover, ctDNA levels harbor prognostic impact since higher levels of ctDNA (22.5 log hGE/mL) showed a significantly worse PFS (p=0.025) and OS (p=0.004). Based on the mutations identified, the LymphGen tool allowed to assign to a specific molecular cluster 46.5% of patients on the LN biopsy, and 40.3% on the liquid biopsy. The combination of mutational data from LN and ctDNA improved DLBCL assignment to a specific cluster, thus classifying 48.7% of cases. From a clinical perspective, patients belonging to the BN2 and ST2 clusters showed a favorable outcome with a 36-month PFS of 100% compared to 62.3% for patients belonging to the MCD or EZB clusters (p=0.040). The combination of mutational data from LN and ctDNA provides complementary information for the molecular classification and prognostic stratification of newly diagnosed DLBCL patients.
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Mackley, Emma Christine. "Investigating the role of innate lymphoid cells in secondary lymphoid tissue." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6479/.
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Innate lymphoid cells (ILCs) are an emerging family of cells which have been well-characterised within the gut and peripheral tissues. Despite being implicated in shaping adaptive immune responses, relatively little is known about their function within lymph nodes (LNs), important sites for the generation of this type of response. The aim of this investigation was to characterise ILC populations within a range of different LNs, both at steady state and using a draining LN model to understand their role in an immune response. Mice in which a subset of ILC, or key functional molecules, are deficient will be used to better understand their function within LNs, with a focus on adaptive immune responses. My results reveal that ILCs are present in all LNs analysed, however, differences in the ILC composition of mucosal tissue and peripheral tissue-draining LNs indicate site-specific requirements for these cells. Differing dependencies on CCR7 for ILC entry into LNs were observed, consistent with migration of these cells into these secondary lymphoid tissues. Within LNs, group 3 ILCs were found to express major-histocompatibility complex class-II and specifically locate to sites where adaptive immune responses are initiated and maintained. Notably, ILCs accumulated in draining LNs following immunisation and whilst their roles here remain unclear they are unlikely to be involved in the priming of naïve CD4+ T cells. In summary, I show that subsets of ILC3 are enriched in LNs which drain mucosal sites and can be found to locate to crucial sites within LNs following their entry by a CCR7-dependent mechanism. These data support a role for ILC3 in adaptive immune responses.
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Bollands, A. D. "Lymphoid tissue responses to emulsified perfluorochemicals." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381097.
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Moorthie, Sowmiya Anandan. "Disease-associated PrP in ruminant lymphoid tissue." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613754.
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Koornstra, Petra. "Waldeyer's ring equivalent lymphoid tissue in the rat a model for studying the immunological role of nose associated lymphoid tissue /." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Maastricht University [Host], 1997. http://arno.unimaas.nl/show.cgi?fid=5912.
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Behbahani, Homira. "Immune dysregulation in HIV-1 infected lymphoid tissue /." Stockholm, 2002. http://diss.kib.ki.se/2002/91-7349-193-4.
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Zonios, George I. 1968. "Diffuse reflectance spectroscopy of human colon tissue." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/29636.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1998.<br>Includes bibliographical references (p. 129-134).<br>Diffuse reflectance spectroscopy can provide quantitative biochemical and morphological information for the analysis of biological tissue epithelium and the detection of precancerous lesions. To investigate this, diffuse reflectance spectra were collected from adenomatous colon polyps (cancer precursors) and normal colonic tissue of patients undergoing colonoscopy. To analyze the data, an analytical model was developed based on the diffusion of light in tissue. The model was formulated in terms of the absorption and scattering properties of tissue. In the case of absorption, hemoglobin was identified as the major absorber of light, and scattering was modeled as a homogeneous of collection spherical microparticles using Mie scattering theory. The validity and accuracy of the analytical model was tested and validated on a physical tissue model (phantom) composed of polystyrene beads and hemoglobin and it was found that it is suitable for application to the tissue data. Four parameters were obtained by analyzing the tissue data using the model: hemoglobin concentration, hemoglobin oxygen saturation, effective scatterer density and size. Normal and adenoma tissue sites exhibited differences in hemoglobin concentration and effective scatterer size, in agreement with other studies which employ standard methods. These results demonstrate that diffuse reflectance can be used to obtain tissue biochemical and morphological information in vivo.<br>by George I. Zonios.<br>Ph.D.
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Reel, Michael Stephen. "The Role of Ectopic Lymphoid Tissue in Allograft Rejection." Yale University, 2006. http://ymtdl.med.yale.edu/theses/available/etd-06282006-140255/.
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The location of the immunologic response to an allograft is not known with certainty. However, organized collections of T cells, B cells and antigen presenting cells have been found in peripheral tissue, in close proximity to organs undergoing rejection. It is hypothesized that this tertiary lymphoid tissue may be a location in which activation of lymphocytes can occur, leading to rejection of an allograft. We report here that in a splenectomized aly/aly mouse, which is devoid of secondary lymphoid organs and will normally fail to reject an allograft, the presence of tertiary lymphoid organs is associated with graft rejection. We additionally find that tertiary lymphoid organs can act as lymph nodes, and can support effector and memory allograft rejection responses. It is demonstrated that ectopic lymphoid tissue in aly/aly mice will support the multiplication and transformation of transferred naïve CD4 and CD8 T cells into cells that display phenotypic markers characteristic of effector and memory lymphocytes. These results demonstrate that ectopic lymphoid tissue is associated with the loss of immunologic ignorance and is sufficient to enable graft rejection. This suggests that allograft rejection may take place within ectopic lymphoid tissue, and suggests that techniques to interfere with the development of this tissue might offer a therapeutic approach to preserving organ allografts.
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Alden, Kieran. "Simulation and statistical techniques to explore lymphoid tissue organogenesis." Thesis, University of York, 2012. http://etheses.whiterose.ac.uk/3220/.
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Secondary lymphoid organs have a key role in the initiation of adaptive immune responses to infection. Organogenesis occurs in foetal development, and the use of genetic tools, imaging technologies, and ex vivo culture systems has provided significant insights into the cellular components and associated signalling pathways that are involved. However such approaches tend to be reductionist and descriptive, focusing on the contribution of individual components, and cannot fully explain how lymphoid organs develop through interaction between biological components. In this study, a set of simulation and statistical tools have been developed that provide further insights into the molecular and biophysical mechanisms of lymphoid tissue organogenesis. Specifically, the formation of Peyer’s Patches, gut-associated secondary lymphoid organs, is examined. In collaboration with experimental immunologists, a structured process in the design and calibration of a computer simulation of the biological process has been conducted, leading to the development of a publicly accessible scientific tool where cell behaviour emerges that is statistically similar to that observed in ex vivo culture. Robust biological hypotheses can be generated through use of the tool to perform in silico experimentation that simulates different physiological conditions. A lack of available statistical tools to analyse in silico simulation results has been addressed through the development and release of the spartan toolkit, a set of techniques that can suggest the influence that pathways and components have on simulation behaviour, offering valuable biological insight into the system being explored. An analysis of simulation results using spartan suggests the influence of biological pathways on tissue formation changes during development, in contrast to hypotheses in the literature that suggest the process is chemokine driven. Data presented suggests the development period is biphasic, with cell adhesion the key factor early in development, and chemokine expression influential at later point. Through novel application of the statistical tools in spartan to perform a time-lapse analysis of cell behaviour, it is suggested this change in phase occurs between hours 24 and 36. Novel in silico experimentation performed has suggested the key biological factors in causing cell aggregation, and suggested a role for LTin cells in limiting size and number of Peyer’s Patches. A range of potential laboratory investigations have been suggested that could validate whether these simulation derived hypotheses are valid.
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Olurinde, Mobolaji O. "Antigen-specific memory T cell distribution in non-lymphoid tissue." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40951.
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Thesis (S.M.)--Massachusetts Institute of Technology, Biological Engineering Division, 2007.<br>Includes bibliographical references (leaves 28-34).<br>CD8+ T cells are the main adaptive immune system cell type responding to intracellular pathogens, particularly viruses, and tumor antigens. In the case of influenza, activated T cells migrate from the mediastinal (draining) lymph nodes to the lung where they perform their cytolytic function. After pathogen clearance, memory CD8+ T cells are generated, giving rise to long-term protection from reinfection. However, these cells are no longer detectable in the lung parenchyma six months post-infection, and cell-mediated immunity, and protection is lost. Knock-out studies in mice show that interleukin 15 (IL-15) is essential for memory CD8+ T cell proliferation. Fibroblasts, macrophages, dendritic cells and epithelial cells express IL-15 and its receptor isoform [alpha] (IL-15R[alpha]). Histological studies suggest that memory CD8+ T cells preferentially reside in peribronchiolar and perivascular areas, the stroma, of the lung. We hypothesize that memory CD8+ T cells preferentially reside in regions where molecules necessary for their maintenance, for example, IL-15/R secreting cells, are located. In this study, we have shown that antigen-specific 2C GFP effector memory CD8+ T cells are generated in B6 recipient mice 30-32 days after influenza virus infection, preferentially reside in peribronchiolar areas. Both 2C and 2C GFP recipient mice have severe vasculitis and widely distributed inflammatory infiltrates 7 days post-infection. Lower lung lobes appear to be more affected than upper lobes at this time point. On day 30, most of the airways have been cleared and restored. Although lymphoid-appearing nodules were detected in the lungs 31 dpi, no clusters of B cells and T cells suggesting induced BALT were identified by immunofluorescence.<br>(cont.) Interestingly, antigen-specific GFP cells preferentially remained in the lung tissue and were almost undetectable in spleens, lymph nodes, and livers. This preference was not observed in 2C (non-GFP) recipient mice. Immunofluorescence studies showed no colocalization between 2C GFP T cells and dendritic cells that might suggest stable dendritic cell interactions contribute to antigen-specific cells preferentially residing in the lung stroma. Further studies are necessary to determine what other cell types might contribute to this phenomenon. These results provide some insight into how structural elements in non-lymphoid tissue influence cell-mediated immunity.<br>by Mobolaji O. Olurinde.<br>S.M.
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Zhao, Mingjun. "NONINVASIVE MULTIMODAL DIFFUSE OPTICAL IMAGING OF VULNERABLE TISSUE HEMODYNAMICS." UKnowledge, 2019. https://uknowledge.uky.edu/cbme_etds/58.
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Measurement of tissue hemodynamics provides vital information for the assessment of tissue viability. This thesis reports three noninvasive near-infrared diffuse optical systems for spectroscopic measurements and tomographic imaging of tissue hemodynamics in vulnerable tissues with the goal of disease diagnosis and treatment monitoring. A hybrid near-infrared spectroscopy/diffuse correlation spectroscopy (NIRS/DCS) instrument with a contact fiber-optic probe was developed and utilized for simultaneous and continuous monitoring of blood flow (BF), blood oxygenation, and oxidative metabolism in exercising gastrocnemius. Results measured by the hybrid NIRS/DCS instrument in 37 subjects (mean age: 67 ± 6) indicated that vitamin D supplement plus aerobic training improved muscle metabolic function in older population. To reduce the interference and potential infection risk on vulnerable tissues caused by the contact measurement, a noncontact diffuse correlation spectroscopy/tomography (ncDCS/ncDCT) system was then developed. The ncDCS/ncDCT system employed optical lenses to project limited numbers of sources and detectors on the tissue surface. A motor-driven noncontact probe scanned over a region of interest to collect boundary data for three dimensional (3D) tomographic imaging of blood flow distribution. The ncDCS was tested for BF measurements in mastectomy skin flaps. Nineteen (19) patients underwent mastectomy and implant-based breast reconstruction were measured before and immediately after mastectomy. The BF index after mastectomy in each patient was normalized to its baseline value before surgery to get relative BF (rBF). Since rBF values in the patients with necrosis (n = 4) were significantly lower than those without necrosis (n = 15), rBF levels can be used to predict mastectomy skin flap necrosis. The ncDCT was tested for 3D imaging of BF distributions in chronic wounds of 5 patients. Spatial variations in BF contrasts over the wounded tissues were observed, indicating the capability of ncDCT in detecting tissue hemodynamic heterogeneities. To improve temporal/spatial resolution and avoid motion artifacts due to a long mechanical scanning of ncDCT, an electron-multiplying charge-coupled device based noncontact speckle contrast diffuse correlation tomography (scDCT) was developed. Validation of scDCT was done by imaging both high and low BF contrasts in tissue-like phantoms and human forearms. In a wound imaging study using scDCT, significant lower BF values were observed in the burned areas/volumes compared to surrounding normal tissues in two patients with burn. One limitation in this study was the potential influence of other unknown tissue optical properties such as tissue absorption coefficient (µa) on BF measurements. A new algorithm was then developed to extract both µa and BF using light intensities and speckle contrasts measured by scDCT at multiple source-detector distances. The new algorithm was validated using tissue-like liquid phantoms with varied values of µa and BF index. In-vivo validation and application of the innovative scDCT technique with the new algorithm is the subject of future work.
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Howard, Kenneth Alan. "The characterisation of the uptake of microparticulates across intestinal lymphoid tissue." Thesis, University of Nottingham, 1994. http://eprints.nottingham.ac.uk/11675/.
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Poly(lactide-co-glycolide) (PLG) biodegradable microparticles were evaluated as an oral delivery system for immunisation against equine influenza virus. Model particulates (fluorescent polystyrene and gold labelled polystyrene) were used to characterise the route and mechanism of intestinal uptake. Peyer's patches were found to be the site of particulate intestinal absorption characterised by phagocytosis at the M cell surface. Microparticles were found within intercellular compartments indicating a paracellular route for the transit of microparticles from lumen to lymph. A quantitative method of counting the number of microparticles passing into the lymph in both the superior mesenteric and thoracic lymph ducts indicated levels of intestinal uptake high enough to deliver vaccines via this route. PLG microparticles encapsulating equine influenza virus were prepared by the process of solvent evaporation. The immune responses were evaluated in mice after either systemic or oral immunisation of Balb\c mice using formalin treated equine influenza (Prague 56 H7N7) either encapsulated in PLG biodegradable microparticles or free in solution. Using the single-radial- immunodiffusion test, the haemagglutinin integrity of the microencapsulated influenza was found to be preserved during the microencapsulation process. When administered systemically the microencapsulated virus induced raised levels of anti-influenza IgG antibody in serum that were comparable with those obtained with the virus in solution. Oral administration of the microencapsulated virus induced raised levels of anti-influenza IgA antibody in saliva as well as levels of anti-influenza IgG comparable to those obtained after parenteral injection. Raised levels (compared to preimmune levels) of anti-influenza antibodies in both the systemic circulation and mucosal secretions indicates that orally administered microencapsulalated equine influenza virus represents a practical method of immunisation against influenza.
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Everitt, David Lewis. "Imaging of tissue-like media with diffuse light : analysis and optimization of a diffuse photon tomography /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Han, Shuhua. "β-lymphocyte differentiation in the periphery." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326157.
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McMillan, Euan Murray. "Human lymphoid cell immunophenotypes : in situ immunochemistry of human lymphoid tissue, benign and malignant cutaneous lymphohistiocytic infiltrates with monoclonal antibodies." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/20012.
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This thesis describes the results obtained with 36 monoclonal antibodies (McAbs) and immunocytochemistry on a) non-malignant lymphoid tissue [thymus (1) (n) = number of specimens tested, lymph node (5), tonsil (15)]. b) 104 skin biopsies of cutaneous lymphoma (40), contact dermatitis (14), parapsoriasis (17), chronic inflammatory dermatosis (9), non-lymphomatous erythroderma (3), atypical lymphocytic infiltrate (3), granulocytic sarcoma (1), lymphocytoma (3), lymphomatoid papulosis (3), lymphocytic infiltrate of Jessner (1), chronic lymphocytic leukaemia (1), myelomonocytic leukaemia (1), histiocytosis X (3), and c) normal scalp (5). In lymphoid tissue, determinants against T, and B cells (and their subsets), macrophages /D cells, and K/NK cells have a distinct topography. Immature thymic determinants OKT6, OKT9, OKT10 are identified in extrathymic locations (tonsil, and/or inflammatory infiltrates as well as lymphomas). OKT6 cross reacts with epithelial dendritic (Langerhans') cells. J5 (common acute lymphoblastic leukemia antigen) is absent in lymphoid tissue but present in some cases of mycosis fungoides. Immature myeloid markers (My10, My12) are absent in lymphoid tissue. The so called leukaemia/lymphoma markers Bel/Be2 react with follicular epithelium (Be1), dermal endothelium (Be2), tonsil (Be2), benign dermatoses (Be1 and Be2) as well as most lymphomas. A mature helper T cell phenotype is usually present in cutaneous T cell lymphoma (CTCL) and inflammatory dermatoses. However, OKT9 and OKT10 are preferentially expressed in CTCL versus parapsoriasis and benign infiltrates. Lymphomas of non-mycosis/Sezary type can be categorized into T, B and U types. They often show aberrant differentiation when examined with multiple markers. Pseudolymphomas, sarcoidosis, leukaemia and histiocytosis X show characteristic phenotypes denoting the expansion of selected lymphohistiocytic subpopulations. The histiocyte of histiocytosis X predictably expresses the OKT6 marker, but in addition reacts with the Leu3A (helper T cell) antibody. Characteristic dendritic cell markers are associated with B (R423+ ) and T (OKT6+ ) populations in lymphoid tissue and skin. K/NK cells are identified in benign and malignant infiltrates. This may have immuno-pharmacological application. The markers used amply illustrate the heterogeneous nature of benign and malignant lymphoid populations.
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Hedden, Jane Ann. "CHARACTERIZATION OF LYMPHOID CELLS IN GOATS WITH CASEOUS LYMPHADENITIS (LECTINS)." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275421.
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Mader, Emma. "The role of NF-kB2 in secondary and tertiary lymphoid tissue development." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1608/.
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The role of the alternative NF-\(\kappa\)B pathway in the development of secondary lymphoid organs (SLOs) has been well described. Tertiary lymphoid organs (TLOs) include intestinal cryptopatches (CPs) and isolated lymphoid follicles (ILFs). This thesis investigates the role of the alternative NF-\(\kappa\)B pathway in the development of colonic ILFs, using the p100\(\Delta\) mouse model, where the alternative pathway is constitutively active. We present compelling data that p100\(\Delta\) mice develop significantly more lymphoid aggregates in the colon, compared with WT littermates, and provide several lines of evidence showing that these aggregates are analogous to ILFs. Additionally, we demonstrate that in the p100\(\Delta\) a significant increase in the numbers of B and T cells, and DCs in the colon and show alterations in the subsets of colonic T cells and DCs. We also present evidence that constitutively active NF-\(\kappa\)B2 p100 in LT\(\alpha\) deficient mice induces recovery of B and T cell segregation in the spleen. Most strikingly, we show recovery of iLNs and mLN development in one of five \(p100\)\(\Delta\)\(LT\)\(\alpha^{-/-}\) mice generated. These findings demonstrate that the alternative NF-\(\kappa\)B pathway plays an important role in not only SLO development and splenic organisation, but also in the development of TLOs, specifically colonic ILFs.
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Kanth, Sheeba Irshad. "Role of RORyt+ innate lymphoid tissue inducer cells within breast cancer microenvironments." Thesis, King's College London (University of London), 2014. https://kclpure.kcl.ac.uk/portal/en/theses/role-of-roryt-innate-lymphoid-tissue-inducer-cells-within-breast-cancer-microenvironments(da9aadf1-96ff-4269-b2c8-f8278af18822).html.
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Within invasive breast cancers, lymphatic invasion is thought to be the first step tumour cells undertake when metastasizing through the lymphatic vasculature. The presence of lymphatic metastasis has been shown to stratify breast cancer phenotypes into distinct prognostic groups. The exact molecular mechanisms mediating tumour cell entry and dissemination within the lymphatic system remain unclear. We report the first identification of RORyt+-innate lymphoid tissue inducer (LTi) cells within the human breast cancer tumour microenvironment and the enrichment of lymphoid chemokines/chemokine receptor gene signature within an aggressive breast cancer subtype. The presence of these cells within the tumour microenvironment was shown to correlate with both an increased lymphatic vessel density (LVD) and tumour invasion into lymphatic vessels. We demonstrate the CCL21-dependent recruitment of LTi cells into breast tumours, the CXCL13-dependent interaction between the tumoural LTi and stromal cells and the downstream effect of the CXCL13 positive feedback loop in promoting lymphatic tumour cell motility via the RANK-RANKL axis. These data suggest a novel role for LTi cells in enhancing lymphatic invasion of tumour cells through modulation of the local lymphoid chemokine profile.
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Sauvage, Vincent. "Fluorescence and diffuse reflectance spectroscopy and endoscopy for tissue analysis." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/10736.
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Biophotonics techniques are showing great potential for practical tissue diagnosis, capable of localised optical spectroscopy as well as wide field imaging. Many of those are generally based on the same concept: the spectral information they enable to acquire encloses clues on the tissue biochemistry and biostructure and these clues carry diagnostic information. Biophotonics techniques present the added advantage to incorporate easily miniaturisable hardware allowing several modalities to be set up on the same systems and authorizing their use during minimally invasive surgery (MIS) procedures. The work presented in this thesis aims to build on these advantages to design biophotonics instruments for tissue diagnosis. Fluorescence and diffuse reflectance, the two modalities of interest in this work, were implemented in their single point spectroscopic and imaging declinations. Two “platforms”, a spectroscopic probe setup and an optical imaging laparoscope, were built; they included either one of the two aforementioned modalities or the two of them together. The spectroscopic probe system was assembled to detect lesions in the digestive tract. In its first version, the setup included a dual laser illumination system to carry out an ex vivo fluorescence study of non-alcoholic fatty liver diseases (NAFLD) in the mouse model. Outcomes of the study demonstrated that healthy livers could be distinguished from NAFLD livers with high classification accuracy. Then, the same fluorescence probe inserted in a force adaptive robotic endoscope was applied on a fluorescence phantom and a liver specimen to prove the feasibility of recording spectra at multiple points with controlled scanning pattern and probe/sample pressure (known to affect the spectra shape). This approach proposed therefore a convincing method to perform intraoperative fluorescence measurements. The fluorescence setup was subsequently modified into a combined fluorescence/diffuse reflectance spectroscopic probe and demonstrated as an efficient method to separate normal and diseased tissue samples from the human gastrointestinal tract. Following the single point spectroscopy work, imaging studies were conducted with a spectrally resolved laparoscope. The system, featuring a CCD/filter wheel unit clipped on a traditional laparoscope was validated on fluorescence phantoms and employed in two experiments. The first one, building on the spectroscopy study of the gastrointestinal tract, was originally aimed at locating tumour in the oesophagus but a lack of tissue availability prevented us from doing so. The system design and validation on fluorophores phantoms were nevertheless described. In the second one, the underarm of a pig was imaged after injection of a nerve contrast agent in order to test the feasibility of in vivo nerve delineation. Fluorescence was detected from the region of interest but no clear contrast between the nerve and the surrounding muscle tissue could be detected. Finally, the fluorescence imaging laparoscope was modified into a hyperspectral reflectance imaging laparoscope to perform tissue vasculature studies. It was first characterized and tested on haemoglobin phantoms with varying concentrations and oxygen saturations and then employed in vivo to follow the haemoglobin concentration and oxygen saturation temporal evolutions of a porcine intestine subsequently to the pig’s termination. A decrease in oxygen saturation was observed. The last experiment consisted in monitoring the tissue re-oxygenation of a rabbit uterus transplant on the recipient animal, a successful tissue re-perfusion after the graft was highlighted.
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Zanfardino, Sara Marie. "SENSITIVITY OF DIFFUSE CORRELATION SPECTROSCOPY TO FLOW RATES IN TISSUE-SIMULATING OPTICAL PHANTOMS." Miami University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=miami1533076561913823.
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Coleman, Leslie Ann. "Immunophenotypic characterization of lymphoid tissue and lymphoproliferative disease in ferrets (Mustela putorious furo)." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43442.
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Glanville, Stephanie Helen. "Analysing the role of lymphotoxin signalling in the development of lymphoid tissue microenvironments." Thesis, University of Birmingham, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.532169.
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The formation of lympho-stromal microenvironments in primary and secondary lymphoid tissues is crucial for the correct and efficient functioning of the immune system. Induction and maintenance of these environments in the spleen requires lymphotoxin (LT)-dependent lymphostromal and Lymphoid Tissue inducer cell (LTi) -stromal interactions resulting in the secretion of chemokines. In contrast the LT-dependence of the thymus is unclear. We have developed an in vivo model to study the formation of splenic microenvironments by grafting embryonic spleens under the kidney capsule of adult mice. These grafts develop into phenotypically and functionally normal splenic tissue, exhibiting B-T segregation, mature stromal cell populations and a normal response to immunisation. Using this model we have shown that adult non-B, non-T cells are sufficient to provide LTa signals to developing splenic stromal cells and propose that adult LTi-like cells are responsible for this. Consistent with this idea we have also shown that LTi-like cells can develop from adult bone marrow precursors. In extending the study of microenvironments to the thymus, we identified key similarities to the spleen including the presence of LTi cells. We further found that in contrast to the spleen, LT signals in the thymus are not essential to maintain tissue organisation but that LTß receptor signals are required to optimise the medullary microenvironment and allow maximal emigration of mature thymocytes from the organ.
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McGovern, Gillian. "Immunocytochemical and ultrastructural studies of lymphoid tissue of scrapie infected mice and sheep." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/30477.
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The transmissable spongiform encephalopathies (TSEs) are a group of progressive neurological diseases of unknown cause. Infection is associated with an abnormal form of a host protein designated ‘prion protein’. Previous studies have shown that lymphoid tissues are involved in the peripheral pathogenesis of TSEs prior to neuroinvasion. Using immunoelectron microscopy, disease specific PrP (PrP<sup>d</sup>) accumulation was demonstrated within the spleens of scrapie-infected mice where it was found in association with the plasmalemma and extracellular space around follicular dendritic cell (FDCs) processes (dendrites), and in the lysosomes of tingible body macrophages (TBMs). In light zones of secondary follicles, almost all FDCs at the terminal stages of disease form hypertrophic labyrinthine glomerular complexes. Within these labyrinthine complexes PrP<sup>d</sup> is consistently seen on the plasmalemma of adjacent dendritic profiles and in association with abundant electron dense material held between dendrites. The latter was interpreted as excess trapped antigen-antibody complexes. Contrary to previous dogma, these results show that a pathological response within the immune system follows murine scrapie infection. The nature of these changes is similar irrespective of the strain of agent used. To help determine the significance of these changes, scrapie-infected mice were inoculated with cytokines that alter the biology of secondary follicles. Tumour necrosis factor receptor fusion protein (Hu-TNFR:Fc) or lymphotoxin β receptor fusion protein (LTβR:Fc), have been reported to induce de-differentiation of FDCs and heighten B cell apoptosis. However, in this study, mature FDCs were present 3 and 35 days after treatment with LTβR:Fc and retained PrP<sup>d</sup> accumulation. The mechanisms by which these cytokines modulate incubation period were not determined. To ensure that the pathology of experimental disease is similar to that occurring in natural disease, ovine scrapie tissue samples were examined. The results presented suggest that natural scrapie is closely similar to that of experimental murine scrapie. Further technique refinement is still necessary to give comparable levels of sensitivity and tissue preservation in ovine tissue.
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Bergomas, Francesca. "Tertiary lymphoid tissue in colorectal cancer : a key player of the immune microenvironment." Thesis, Open University, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.701365.
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Tumour infiltrating Iymphocytes influence colorectal cancer (CRC) progression. However, Iymphocyte infiltration comes in different flavours and evidence has been provided that the spatial distribution of immune cells within the tumour tissue is an important immunological feature. The aim of this thesis was to investigate how the dual localization of tumour infiltrating Iymphocytes (TILs) can affect their function in the tumour microenvironment. The project started with the analysis of the CD3 compartment, as CD3+ T cell infiltration (C03-TILs) is a recognized positive prognostic factor for CRC patients. Results here presented show that CD3+ tumour- infiltrating Iymphocytes are present both interspersed in the tumour tissue or scattered throughout the stroma (CD3- TILs) and also aggregated in lymphoid structures showing features of tertiary lymphoid tissue (CD3-TLT). Tumour- associated TLT had a peculiar compartmentalization, with CD3+ T cells and CD20+ B lymphocytes holding complementary positions and with distinct types of dendritic cell populations among them. The presence of HEVs (High Endothelial Venules) suggests a role for TLT in T cell recruitment at the tumour site. To test this hypothesis in human cancer, I performed a whole tissue analysis of the CD3+ infiltrate on CRC sections and found a positive correlation between CD3-TIL and CD3- TLT densities. I further confirmed the hypothesis in vivo in a murine model of colitis- associated cancer (AOM/DSS). AOM/DSS treated mice had expanded TLT compared to control mice. Intravenously injected GFP+ splenocytes localised in TLT of tumour- bearing mice more than in control mice. I then investigated the clinical significance of CD3-TLT in relationship with CD3-TILs in a cohort of 351 CRC patients. In patients with node-negative (without lymph node metastasis, stage 11) CRC, a high density of CD3-TLT and CD3-TILs associated to a better prognosis, while in patients with node- positive (presence of lymph node metastasis, stage Ill) CRC, TLT and TIL density were irrelevant in predicting patient prognosis, thus behaving as biomarkers only for early stage CRC patients. In the second part of my thesis, I analysed the distribution of B cells in colorectal cancer and their : possible contribution to disease progression. Despite still controversial, increasing evidence that B cells play a role in cancer progression has been provided, bringing up the hypothesis that also B-cell responses should be considered as targets of immunotherapeutic approaches. Similarly to CD3+ cells, I showed that, both in human and in preclinical models of CRC, B cells display a dual geographical distribution, either within tertiary lymphoid tissue (CD2D-TLT) or dispersed at the tumour invasive margin (CD2D-TILs). Therefore, I evaluated the role of B cells according to their localization in the microenvironment. I found that CD2D- TLT associated to better prognosis, while CD2D-TILs did not. Interestingly, C02D-TLl correlated with CD2D-TILs only among patients who experienced cancer recurrence. This result suggests that, when located within a lymphoid site, B cells might have a protective anti-tumour function, participating in an anti-tumour immune response. Conversely, the distribution of B cells scattered in the microenvironment is likely to reflect a non-specific pro-tumour inflammatory reaction. To confirm the hypothesis in vivo and attempt to dissect the dual function of B cells, I took advantage of two CRC preclinical models in which B cells present a distinct geographical distribution in the tumour microenvironment. In the first model, B cells mainly localise within TLT, while in the second one B cells diffusely infiltrate the mucosa, without forming aggregates. I found that in a model in which B cells localize primarily within TLT, the genetic deficiency of B cells significantly increased tumour formation, suggesting that B cells within TLT might exert an important anti-tumour function. In contrast, in a model in which B cells only localize within the tissue, genetic deficiency of B cells reduces tumour growth, suggesting that infiltrating B-TILs might have a pro-tumour role. Therefore, the occurrence of TLT is associated with Iymphocyte infiltration in CRC, contributing to recruitment of CD3-TILs. TLT and TILs work together to set up an anti- tumour immune response in patients with low-risk early-stage colorectal cancer. Thus, TLT represents a novel prognostic biomarker for CRC. As to the B cell compartment, their differential distribution in the tumour site corresponds to distinct prognostic functions. This evidence suggests that the design of novel immunotherapeutic drugs depleting B cells should take into account their ability to selectively targeting CD20-TILs but not C20-TLT.
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Nagarajan, Vivek Krishna. "REAL-TIME ASSESSMENT OF THERMAL TISSUE DAMAGE USING DIFFUSE REFLECTANCE SPECTROSCOPY." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1494313847936136.
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Masjedi, Mohsen. "Physiological inflammation of the small intestine during weaning in the rat /." Title page, table of contents and summary only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phm3973.pdf.
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Orr, L. E. "Raman spectroscopy of laryngeal and lymphoid tissue : an application in optical diagnosis of malignancy." Thesis, Cranfield University, 2010. http://dspace.lib.cranfield.ac.uk/handle/1826/4528.
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The use of Raman spectroscopy in the detection and classification of malignancy within the human larynx and lymph nodes of the head and neck has been evaluated. Currently histopathology is considered the diagnostic gold standard. The potential for Raman spectroscopy to be used as an in vivo diagnostic tool in the detection of dysplasia and malignancy has been demonstrated. A consensus opinion from three expert histopathologists has been obtained and spectral diagnostic models developed by correlation with these results. The ability of Raman spectroscopy to differentiate between disease entities and normal tissue within the larynx has been shown. Raman spectroscopy was able to identify non-neoplastic vocal cord mucosa (sensitivity 85 %, specificity 95%) from laryngeal mucosa showing neoplastic change (sensitivity 95 %, specificity 85%) with an increase in sensitivity to 89% for the non-neoplastic tissue and a reduction to73% in tissues showing neoplastic changes after cross-validation. For the first time benign changes in the structure of vocal cords such as those exhibiting hyperkeratosis and hyperplasia, where also identified with sensitivity of 97.9% for tissue exhibiting hyperplasia/hyperkeratosis and 100% for normal squamous cell epithelium. Research into the ability of Raman spectroscopy to interrogate lymphoid tissue in order to differentiate reactive nodes (sensitivity 90 %, specificity 88%) from those containing cancer (sensitivity 88 %, specificity 90%) was successful and fully independently validated. This work was further developed and the efficacy of Raman spectroscopy in differentiating between squamous cell carcinoma (sensitivity 76%, specificity 95%), adenocarcinoma (sensitivity 93 %, specificity 99%), Hodgkin‘s lymphoma (sensitivity 80%, specificity 90%) and reactive lymph nodes (sensitivity 81%, specificity 88%) was shown. This model was also independently cross-validated by node producing further improvements to give a spectral performance of sensitivity/specificity for SCC of 75/97%, adenocarcinoma 100/99%, Hodgkin‘s lymphoma 83/92% and reactive lymph nodes 85/86%.
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Tawadros, Fady, Sakshi Singal, Maria Zayko, and Devapiran Jaishankar. "Mucosal Associated Lymphoid tissue of the Skin, A Common Entity in a Rare Location." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/asrf/2019/schedule/55.
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Marginal zone (MZ) lymphomas (MZLs) represent a group of lymphomas originating from B lymphocytes of the “marginal zone” which is the external part of the secondary lymphoid follicles. The WHO classifies MZL into 3 entities; extranodal MZL, splenic MZL and nodal MZL. Extranodal marginal zone lymphoma (EMZL) can arise in different tissues, including the stomach, salivary gland, lung, small bowel, thyroid, ocular adnexa and skin. We present a 25 years old female with a history of angioedema and chronic cutaneous eczema who developed an unusual EMZL. Patient presented with a history of rapidly enlarging skin nodule on her left elbow that had been present for almost one year. Over a period of 2-3 weeks she felt the nodule rapidly changed in size and shape. Excisional biopsy of the mass revealed a lymphoid infiltrate based in the reticular dermis and focally extending into the subcutaneous adipose tissue with formation of disrupted lymphoid follicles positive for CD20, CD23 and BCL2 but negative for CD10, Cyclin D1 and SOX11. Diagnosis was consistent with extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). Patient on presentation did not have any B symptoms other cutaneous lesions, lymphadenopathy or hepatosplenomegaly. PET scan revealed no evidence of abnormal uptake leading to a final Stage IE definition. Patient initiated definitive radiation therapy. EMZL accounts for 5 -10 % of non-Hodgkin lymphoma. It has been described often in organs that are normally devoid of germinal centers. It may arise in reactive lymphoid tissue induced by chronic inflammation in extranodal sites. Primary cutaneous marginal zone lymphoma (PCMZL) is associated with infectious etiologies such as Borrelia burgdorferi and less commonly with viral infections or in relation to autoimmune disorders. Autoimmune disorders, specifically Sjögren's syndrome is associated with a 30-fold increased risk of marginal zone lymphoma. Localized disease can be treated by local radiotherapy, intralesional injections or excision. Widespread skin disease is usually treated with a CD20 directed monoclonal antibody-Rituximab. Patients with PCMZL usually have an indolent clinical course. Extracutaneous dissemination of MALT Lymphoma is uncommon and happens in 6-8 % of patients. The 5 years overall survival is between 98-100%. Family physicians and dermatologists should have a high index of suspicion for this rare lymphoma subtype especially in patients with inflammatory chronic skin conditions and atopy.
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Farzam, Parisa. "Hybrid diffuse optics for monitoring of tissue hemodynamics with applications in oncology." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/283982.
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Noninvasive measurement of hemodynamics at the microvascular level may have a great impact on oncology in clinics for diagnosis, therapy planning and monitoring, and, in preclinical studies. To this end, diffuse optics is a strong candidate for noninvasive, repeated, deep tissue monitoring.
In this multi-disciplinary, translational work, I have constructed and deployed hybrid devices which are the combination of two qualitatively different methods, near infrared diffuse optical spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS), for simultaneous measurement of microvascular total hemoglobin concentration, blood oxygen saturation and blood flow.
In a preclinical study, I applied the hybrid device to monitor the response of renal cell carcinoma in mice to antiangiogenic therapy. The results suggest that we can predict the output of therapy from early hemodynamic changes, which provide us with valuable information for better understanding of the tumor resistance mechanism to antiangiogenic therapies.
In two in vivo studies in human volunteers, I have developed protocols and probes to demonstrate the feasibility of noninvasive diffuse optical spectroscopy to investigate the pathophysiology of bone. First study was study on the physiology of the patella microvasculature, the other introduced the manubrium as a site that is rich in red bone mar- row and accessible to diffuse optics as a potential window to monitor the progression of hematological malignancies.
Overall, during my Ph.D., I have developed instrumentation, algorithms and protocols and, then, applied this technique for preclinical and clinical investigations. My research is a link between preclinical and clinical studies and it opens new areas of applications in oncology.<br>La medición no invasiva de la hemodinámica a nivel microvascular puede alcanzar un gran impacto en oncología: en las clínicas para el diagnóstico, la planeación y monitorización de las terapias, y en estudios preclínicos. La óptica difusa es una fuerte candidata para la monitorización no invasiva y repetida del tejido profundo. En este trabajo multidisciplinario y traslacional, construí e implementé dispositivos híbridos que son la combinación de dos métodos cualitativamente diferentes: espectroscopía infrarroja de óptica difusa -near infrared diffuse optical spectroscopy (NIRS)- y espectroscopía de correlación de luz difusa -diffuse correlation spectroscopy (DCS)-. Estos híbridos permiten la medición simultánea de la concentración de hemoglobina total en sangre, la saturación de oxígeno y el flujo sanguíneo. En un estudio preclínico, apliqué el dispositivo híbrido para monitorizar la respuesta de carcinomas de células renales, implantados en ratones, a terapias antiangiogénicas. Los resultados sugieren que podemos predecir la evolución de la terapia con base en cambios hemodinámicos tempranos, lo cual proporciona información valiosa para un mejor entendimiento del mecanismo de resistencia de los tumores a las terapias antiangiogénicas. En dos estudios in vivo realizados en pacientes voluntarios, desarrollé protocolos y sondas para demostrar la viabilidad de la espectroscopía de óptica difusa no invasiva en el estudio de la patofisiología ósea. El primer estudio se concentró en la fisiología microvascular de la rótula y en el otro se muestra que el manubrio, hueso rico en médula ósea roja, es un sitio accesible para la óptica difusa, y se presenta como una ventana para monitorizar la progresión de enfermedades hematológicas malignas. En resumen, durante mi trabajo doctoral, desarrollé instrumentación, algoritmos y protocolos que posteriormente apliqué en estudios preclínicos y clínicos. Mi trabajo de investigación constituye así un enlace entre estos estudios y abre nuevas áreas de aplicación en oncología.
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Nardini, Elena. "Characterization of genetic events involving IgH switch regions in gastric low grade MALT lymphomas and B CLL." Thesis, Open University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251405.
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Satou, Yuuki. "Heterogeneous fibroblasts underlie age-dependent tertiary lymphoid tissues in the kidney." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225471.
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Cooley, Lauren Folgosa. "The role of ADAM10, ADAM17, and Spag6 in humoral immunity and secondary lymphoid tissue architecture." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3808.
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ADAM10, ADAM17, and SPAG6 contribute significantly to humoral immunity and secondary lymphoid tissue architecture. ADAM10 and ADAM17 are two closely related zinc-metalloproteinases. Through cleavage of their ligands CD23 and TNF, respectively, they greatly influence IgE production and secondary lymphoid tissue architecture maintenance. Th1 prone WT strains initially exhibit increased ADAM17 and TNF yet reduced ADAM10 relative to Th2 prone WT strains. In the absence of B cell ADAM10, a compensatory increase in ADAM17 and TNF cleavage is noted only in Th1 prone C57Bl/6, not Th2 prone Balb/c. B cell TNF homeostasis is important for maintaining secondary lymphoid tissue architecture. We show for the first time that excessive B cell TNF production in C57-ADAM10B-/- lymph nodes contributes to loss of B/T segregation, increased HEV number and size, fibrosis, loss of FDC networks, and impaired germinal center formation. Furthermore, B cell ADAM10, which enhances IgE production through CD23 cleavage, is shown to be a marker of Th2 susceptibility. B cell ADAM10 is elevated in Th2 prone mouse strains and allergic patients compared to Th1 prone controls and as B cell ADAM10 level increases, so does IgE production. Lastly, the B cell profile of allergic patients is determined to be B cell ADAM10highADAM17lowTNFlow.
Furthermore, the mechanism underlying reduced class-switched antibody production in C57-ADAM10B-/- mice is explored. C57-ADAM10B-/- B cells exhibit a B10, or IL-10 producing, phenotype, which is linked to reduced antibody production. Furthermore, increased Tregs noted in C57-ADAM10B-/- mice contributed to reduced class switched IgE production and disease parameters following a house dust mite airway inflammation challenge.
SPAG6, a component of the central apparatus of the “9+2” axoneme, plays a central role in flagellar stability and motility. Immune cells lack cilia, but the immunological synapse is a surrogate cilium as it utilizes the same machinery as ciliogenesis including the nucleation of microtubules at the centrosome. We demonstrate that Spag6 localizes in the centrosome and is critical for centrosome polarization at and actin clearance away from the synapse between CTL and target cells. Furthermore, improper synapse formation and function likely explains reduced CTL function and class-switched antibody production in Spag6KO mice.
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Häggblad, Erik. "In Vivo Diffuse Reflectance Spectroscopy of Human Tissue : From Point Measurements to Imaging." Doctoral thesis, Linköpings universitet, Biomedicinsk instrumentteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15191.
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This thesis presents the non-invasive use of diffuse reflectance spectroscopy (DRS) to provide information about the biochemical composition of living tissue. During DRS measurements, the incident, visible light is partially absorbed by chromophores but also scattered in the tissue before being remitted. Human skin and heart, the main tissue objects in this thesis, are dependent on a sufficient inflow of oxygenized blood, and outflow of metabolic byproducts. This process could be monitored by DRS using the spectral fingerprints of the most important tissue chromophores, oxyhemoglobin and deoxyhemoglobin. The Beer-Lambert law was used to produce models for the DRS and has thus been a foundation for the analyses throughout this work. Decomposition into the different chromophores was performed using least square fitting and tabulated data for chromophore absorptivity. These techniques were used to study skin tissue erythema induced by a provocation of an applied heat load on EMLA-treated skin. The absorbance differences, attributed to changes in the hemoglobin concentrations, were examined and found to be related to, foremost, an increase in oxyhemoglobin. To estimate UV-induced border zones between provoked and nonprovoked tissue a modified Beer-Lambert model, approximating the scattering effects, was used. An increase of chromophore content of more than two standard deviations above mean indicated responsive tissue. The analysis revealed an edge with a rather diffuse border, contradictory to the irradiation pattern. Measuring in the operating theater, on the heart, it was necessary to calculate absolute chromophore values in order to assess the state of the myocardium. Therefore, a light transport model accounting for the optical properties, and a calibrated probe, was adopted and used. The absolute values and fractions of the chromophores could then be compared between sites and individuals, despite any difference of the optical properties in the tissue. A hyperspectral imaging system was developed to visualize the spatial distribution of chromophores related to UV-provocations. A modified Beer-Lambert approximation was used including the chromophores and a baseline as an approximate scattering effect. The increase in chromophore content was estimated and evaluated over 336 hours. In conclusion, advancing from a restricted Beer-Lambert model, into a model estimating the tissue optical properties, chromophore estimation algorithms have been refined progressively. This has allowed advancement from relative chromophore analysis to absolute values, enabling precise comparisons and good prediction of physiological conditions.
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Irwin, Daniel. "INFLUENCE OF TISSUE ABSORPTION AND SCATTERING ON DIFFUSE CORRELATION SPECTROSCOPY BLOOD FLOW MEASUREMENTS." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_theses/136.
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This investigation evaluates the influences of optical property assumptions on nearinfrared diffuse correlation spectroscopy (DCS) flow index measurements. Independent variation is induced in optical properties, absorption coefficient (μa) and reduced scattering coefficient (μs’), of liquid phantoms with concurrent measurements of flow indices. A hybrid instrument is incorporated consisting of a dual-wavelength (785 and 830 nm) DCS flow device to obtain flow indices and a frequency-domain tissue-oximeter for optical properties. Flow indices are calculated with measured μa and μs’ or assumed constant μa and μs’. Inaccurate μs’ assumptions produced much larger flow index errors than inaccurate μa. Underestimated/overestimated μs’ from -35%/+175% lead to flow index errors of +110%/-80% and underestimated/overestimated μa from -40%/+150% lead to -20%/+40%, regardless of wavelength. Analysis of a clinical study involving human head and neck tumors indicates flow index errors due to inter-patient optical property variations up to +280%. Collectively, these findings suggest that studies involving significant μa and μs’ changes should measure flow index and optical properties simultaneously to accurately extract blood flow information. This study provides unique insight through the use of liquid phantoms, hybrid instrumentation, incorporation of measurement errors and a generalization into DCS flow index errors due to the influences of optical properties.
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Häggblad, Erik. "In vivo diffuse reflectance spectroscopy of human tissue : from point measurements to imaging /." Linköping : Department of Biomedical Engineering, Linköpings universitet, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15191.
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Liang, Bin. "Characterisation of the mucosal immunity in the nasal-associated lymphoid tissue following influenza A virus infection." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271049.
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Norrman, Johanna. "Effects of glucocorticoids and colostrum feeding on Gut-associated lymphoid tissue and thymus in neonatal calves /." [S.l.] : [s.n.], 2003. http://www.stub.unibe.ch/html/haupt/datenbanken/diss/bestell.html.
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Zedebski, Rosário de Arruda Moura. "Caracterização morfológica, funcional e de ocorrência das tonsilas linguais laterais." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/25/25136/tde-04102007-100956/.
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Propôs-se a caracterização morfológica, funcional e de ocorrência das tonsilas linguais laterais. Compondo o Grupo experimental I, 25 espécimes de línguas humanas foram fixados em solução de formol a dez por cento e assim mantidos até o processamento. Os espécimes foram submetidos à exposição radiográfica para detecção de algum tecido mineralizado. As peças anatômicas foram examinadas a olho nu e com a utilização do estereomicroscópio. Obtiveram-se três blocos de tecido para a análise microscópica de cada espécime: um advindo da tonsila lingual e outros dois das margens laterais da região posterior do terço médio lingual, direito e esquerdo, respectivamente. Após o processamento histotécnico de rotina para coloração em hematoxilina-eosina de Harris, os espécimes foram analisados microscopicamente. Compondo-se o Grupo experimental II, procedeu-se à análise clínica dos tecidos moles bucais de 420 crianças em idade escolar, advindas da rede pública de ensino da cidade de Monte Negro, Estado de Rondônia, com o objetivo de se detectar a presença de tonsilas linguais laterais. Todas as análises, laboratoriais e clínicas, foram realizadas de forma descritiva e os dados obtidos, organizados e demonstrados comparativamente em tabelas e gráficos, com dados de freqüências absolutas e relativas. A análise clínica teve seus dados coletados correlacionados com a utilização do teste do quiquadrado. Aplicou-se a estatística kappa. Ao exame macroscópico: dos 25 espécimes de línguas humanas, nove apresentavam tonsilas linguais laterais (36%); o número de cristas nas papilas folhadas variou de um a seis. Ao microscópio óptico notou-se a presença de 16 espécimes com presença de tonsilas linguais laterais (64%, n=25); epitélio estratificado pavimentoso não queratinizado, com formação de criptas tonsilares e presença subepitelial de folículos linfóides. Na análise clínica, Grupo experimental II, o percentual de ocorrência de tonsilas linguais laterais (3,09%, n=420) foi proporcionalmente menor do que aquele obtido nos espécimes do Grupo experimental I (36%, n=25). Conclui-se que a ocorrência de tonsilas linguais laterais é maior quando obtida por análise microscópica, em comparação com a análise clínica. A presença e a morfologia das papilas folhadas linguais são inconstantes, quer no mesmo espécime, quer de um espécime para outro e podem mascarar a presença de tonsilas linguais laterais.<br>This study aimed to characterize the lateral lingual tonsils as to their morphology, function and occurrence. The experimental group I was composed of 25 specimens of human tongues fixated and kept in 10% formalin until processing. The specimens were radiographed for detection of any mineralized tissue. The specimens were examined by naked eye and with aid of a stereomicroscope. Three blocks of tissue were obtained from each specimen for microscopic analysis: one from the lingual tonsil and two from the lateral borders of the posterior region of medium, right and left thirds, respectively. After routine histotechnical processing and staining with Harris hematoxylin and eosin, the specimens were microscopically analyzed. The experimental group II was achieved by clinical analysis of oral soft tissues of 420 schoolchildren attending public schools at the city of Monte Negro, State of Rondônia, to investigate the presence of lateral lingual tonsils. All laboratory and clinical analyses were performed descriptively and data were organized and comparatively demonstrated on tables and graphs, presenting absolute and relative frequencies. The results of clinical analysis were correlated by utilization of the chisquare test. The kappa statistics was applied. Macroscopic examination of 25 specimens of human tongues revealed that nine presented lateral lingual tonsils (36%); the number of crests in each foliate papilla ranged from one to six. At the microscopic analysis of 25 specimens revealed that 16 presented lateral lingual tonsils (64%, n=25); non-keratinized stratified squamous epithelium with formation of tonsillar crypts and subepithelial presence of lymphoid follicles. With regard to clinical analysis of experimental group II, the percentage of occurrence of lateral lingual tonsils (3.09%, n=420) was proportionally lower than observed on specimens in experimental group I (36%, n=25). It was concluded that the occurrence of lateral lingual tonsils is higher when analyzed by microscopic analysis compared to clinical analysis. The presence and morphology of foliate papillae of the tongue are inconstant, both within and between specimens. They can mask lateral lingual tonsils.
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Levy, Blitchtein Saul, Rebata Stefany Plasencia, Domingo Morales Luna, and Valle Mendoza Juana Del. "Coexistence of papillary thyroid microcarcinoma and mucosa-associated lymphoid tissue lymphoma in a context of Hashimoto’s thyroiditis." Elsevier B.V, 2016. http://hdl.handle.net/10757/615646.
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Papillary thyroid cancer (PTC) represents 80%-85% of thyroid cancer and its prevalence has been rising in the last decades. Primary thyroid lymphoma (PTL) accounts for 3% of extranodal lymphomas and about 5% of thyroid malignancies, having a prevalence of one or two cases per million people. Mucosa-Associated Lymphoid Tissue lymphoma represents approximately 30% of PTL. Both entities have an indolent course and a very good prognosis. Diagnosis is made by ultrasound and fine needle aspiration (FNA) or surgery specimen pathology. They have also been associated with HT, but pathogenesis and its links remains to be known. Treatment remains controversial and surgery is generally accepted in cases of disease limited to thyroid, as the present. Patients with thyroid nodules should be observed and followed. If there is an enlargement by ultrasound or clinical symptoms, FNA should be performed promptly. Patients with Hashimoto’s thyroiditis (HT) deserve additional surveillance, since this condition is associated with both PTC and PTL. In this case, the management with surgery and radioactive iodine ablation therapy was effective for both entities. Patients with thyroid nodules should be properly evaluated with ultrasound and thyroid function tests. If there is an enlargement of the neck, reported by symptoms or ultrasound, it requires further investigation. HT is associated to both PTC and PTL so if the enlargement of the nodules is on this context additional tests such as FNA should be performed. In this case, the patient was managed with surgery and radioactive iodine ablation therapy and it was effective for both entities.<br>Revisión por pares
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Guérin, Violaine. "Implication du m. A. L. T. (mucosal associated lymphoid tissue) dans la physiopathologie des dysthyroidies auto-immunes." Nancy 1, 1988. http://www.theses.fr/1988NAN11214.
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MERCURIO, VINCENZO. "HIV-1 INFECTED HUMAN LYMPHOID TISSUE REMAINS IMMUNE-ACTIVATED DESPITE ART: SOLUBLE AND EXTRACELLULAR VESICLE-ASSOCIATED CYTOKINES." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/701595.
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Background In the age of efficient antiretroviral therapy (ART), premature aging (that includes the development of various pathologies) of HIV-1-infected patients with suppressed viral replication becomes an important health problem. These pathologies are associated with residual immune activation after successful ART. Cytokines, which sustain immune activation, can be either in a soluble form or can be associated with extracellular vesicles (EVs). Together with classical soluble cytokines, these EV-associated cytokines may play a key role in HIV-1 infection and pathogenesis. These hypotheses should be tested in a biologically-relevant system under controlled laboratory conditions. Human ex vivo lymphoid tissues constitute such a system. It was previously used to study HIV-1 pathogenesis, and similar to the situation in vivo, soluble cytokines were shown to be upregulated in this system upon HIV-1 infection. Here we investigated the modulation of both soluble and EV-associated cytokines following HIV-1 infection and upon application of ART. We investigated whether the HIV-1-triggered immune activation is decreased when viral replication is suppressed. We considered various hypotheses on the mechanisms of HIV-1-triggered immune activation: persistent immunological and inflammatory response after an initial cytokine storm; presence of defective virions sustaining immune activation; latent herpesvirus infection which may be reactivated during HIV-1 infection and leading to an inflammatory response; or proinflammatory effects of antiretroviral drugs themselves. Methods Ex vivo lymphoid tissues were infected with two HIV-1 strains: X4LAI04 or R5SF162. HIV-1 was either allowed to replicate for 16 days, or tissues were treated with ritonavir (RTV) or AZT-3TC at day 3 post-infection (n=8). Ex vivo cultures were also treated with cytokines (n=4), inactivated HIV-1 virions (n=4), or ART in the absence of HIV-1 infection (n=8). HIV-1 replication was analyzed in tissue culture supernatants by measurement of p24gag antigen. EV presence was confirmed by Western Blot and Nanoparticle Tracking Analysis (NTA). 33 cytokines in soluble and EV-associated forms were measured with multiplexed bead-based assays. Herpesvirus DNA copies in tonsillar tissue (n=4) were quantified with droplet digital PCR (ddPCR). Results We found that both strains of HIV-1 replicated well in tissues and triggered an upregulation of numerous soluble cytokines as early as day 3 post infection. Many cytokines that were upregulated upon HIV-1 infection in soluble form were increased in EV-associated form as well. However, some cytokines were uniquely upregulated only in the EV form, mainly in response to X4LAI04 infection. In early HIV-1 infection, there was a significant increase in the percentage of soluble RANTES and TNF-α compared to EV-associated; additionally, RANTES significantly increased in the percentage of EV surface associated compared to EV internal. Cytokines which were significantly upregulated throughout culture as evaluated by cumulative totals included: IL-2, IFN-γ, MIP-1α, MIP-1β and RANTES for both virus infections. X4LAI04 infection also led to increases in IL-7, IL-18, M-CSF and TNF-α. An even greater number of cytokines were upregulated in EV-associated form; including many of the same cytokines that were increased in soluble form, but additionally IL-1α, IL-6, IL-13, IL-21, IL-33, GM-CSF and TGF-β were upregulated following X4LAI04 infection. RTV and AZT-3TC treatment of tissues efficiently suppressed viral replication (>99% suppression for both treatments). Despite control of viral replication, cytokines remained upregulated after 13 days of ART treatment, and EV-associated cytokines were less likely to decrease than soluble ones. X4LAI04 induced stronger immune responses as measured by increased soluble and EV-associated cytokines, particularly pro-inflammatory cytokines and the -chemokines MIP-1α, MIP-1β and RANTES, compared to R5SF162 strain. These X4LAI04 cytokine upregulations, especially the β-chemokines, were also less likely to be restored after both antiretroviral treatments. Additional experiments demonstrate that this persistent immune activation was not due to the initial cytokine storm. The emulation of an initial cytokine stimulation was able to boost the production of other cytokines early in culture, but these increases were not maintained over time. Inactivated X4LAI04 was able to trigger a similar, but slightly weaker cytokine release compared to the infectious virus. A single inoculation of inactivated virus elevated many of the same cytokines as live virus; 7 of 13 upregulated cytokines with live virus were increased with inactivated virus. Repeated exposure to inactivated virus generated an even more similar response compared to real infection; almost all the same cytokines were upregulated and some of them were more elevated with inactivated virus (IL-21, MIP-1α, MIP-1β, RANTES and TNF-α. Herpesvirus (HSV-2, EBV, CMV, HHV-6, and HHV-7) DNA copies were detected at different time points at variable concentrations. However, no obvious pattern of herpesvirus reactivation was observed that would account for the immune activation. Finally, the antiretroviral treatments themselves were not responsible for immune activation since only small but significant decreases were observed for a few cytokines. Conclusions HIV-1 infection of ex vivo human lymphoid tissues led to upregulation of various cytokines, in both soluble and EV-associated forms. HIV infection altered distribution of certain cytokines between soluble and EV-associated forms, as well as between EV-surface and EV-encapsulation. Despite viral suppression by ART, the majority of the upregulated cytokines, especially β-chemokines, remained upregulated, similar to the in vivo situation. EV-associated cytokines were more likely to remain elevated than soluble ones. The ex vivo human tissue model was further employed to test various hypotheses on HIV-triggered immune activation. It was determined that an initial cytokine storm did not change the basal setpoint, there was no correlation with reactivation of latent herpesviruses, and ART by itself did not trigger immune activation; however, the presence of noninfectious viral particles can trigger a response similar to infectious virus.
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Quigley, Máire. "Characterisation of CD8 T cells in mucosa associated lymphoid tissue: implications for immune control of HIV-1 infection /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-646-8/.
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Doggett, Teresa Ann. "The structure and function of peripheral blood leucocytes and gut-associated lymphoid tissue in the cichlid, Oreochromis mossambicus." Thesis, University of Plymouth, 1989. http://hdl.handle.net/10026.1/2776.
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The peripheral blood of O.mossambicus was examined using light and electron microscopy and was found to contain four forms of leucocytes: lymphocytes, thrombocytes, monocytes and three types of granulocytes. The monocyte and two types of granulocyte were found to be phagocytic and ingest colloidal carbon and bacteria. The alimentary tract was found to contain a number of leucocytes, some showing a morphological similarity to those in the peripheral blood, while others were unique to the gut tissue. These intestinal leucocytes were found mainly as a diffuse cell population in the epithelium and lamina propria, and only occasionally as discrete lymphoid accumulations within the gut tissue. Ontogenic studies showed that a limited number of leucocytes were found in the gut tissue after hatching, however, there was a gradual increase in these numbers once exogenous feeding began. The intestinal enterocytes of both the anterior and posterior intestine were found to take up intubated macromolecules. An electron microscopical investigation revealed that these macromolecules were absorbed by pinocytosis and were found within large intraepithelial macrophages. These macromolecules were also absorbed and transported into the systemic circulation. In juvenile fish macromolecules were detected in the plasma following both oral and anal intubation, however, in adult fish they were detected in the plasma only after anal intubation, and in smaller quantities. Macromolecular absorption in O.mossambicus was compared to that in two other fish species, Cyprinus carpio and Sa1mo gairdneri, and it was found that higher levels of absorbed macromolecules were found in the plasma of O.mossambicus. Bovine serum albumin absorption by the gut of the three species revealed that both the 'intact' macromolecule and smaller antigenic fragments, probably resulting from enzymatic modification, were ansorbed and transported into the plasma.
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Quigley, Máire. "Characterisation of CD8 T cells in mucosa associates lymphoid tissue implications for immune control of HIV-1 infection /." Stockholm : Karolinska Institutet, 2006. http://diss.kib.ki.se/2006/91-7140-646-8/thesis.pdf.
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Ti, Yalin. "In Vivo Characterization of Myocardial Tissue Post Myocardial Infarction Using Combined Fluorescence and Diffuse Reflectance Spectroscopy." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/95.
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Accurately assessing the extent of myocardial tissue injury induced by Myocardial infarction (MI) is critical to the planning and optimization of MI patient management. With this in mind, this study investigated the feasibility of using combined fluorescence and diffuse reflectance spectroscopy to characterize a myocardial infarct at the different stages of its development. An animal study was conducted using twenty male Sprague-Dawley rats with MI. In vivo fluorescence spectra at 337 nm excitation and diffuse reflectance between 400 nm and 900 nm were measured from the heart using a portable fiber-optic spectroscopic system. Spectral acquisition was performed on - (1) the normal heart region; (2) the region immediately surrounding the infarct; and (3) the infarcted region - one, two, three and four weeks into MI development. The spectral data were divided into six subgroups according to the histopathological features associated with various degrees / severities of myocardial tissue injury as well as various stages of myocardial tissue remodeling, post infarction. Various data processing and analysis techniques were employed to recognize the representative spectral features corresponding to various histopathological features associated with myocardial infarction. The identified spectral features were utilized in discriminant analysis to further evaluate their effectiveness in classifying tissue injuries induced by MI. In this study, it was observed that MI induced significant alterations (p < 0.05) in the diffuse reflectance spectra, especially between 450 nm and 600 nm, from myocardial tissue within the infarcted and surrounding regions. In addition, MI induced a significant elevation in fluorescence intensities at 400 and 460 nm from the myocardial tissue from the same regions. The extent of these spectral alterations was related to the duration of the infarction. Using the spectral features identified, an effective tissue injury classification algorithm was developed which produced a satisfactory overall classification result (87.8%). The findings of this research support the concept that optical spectroscopy represents a useful tool to non-invasively determine the in vivo pathophysiological features of a myocardial infarct and its surrounding tissue, thereby providing valuable real-time feedback to surgeons during various surgical interventions for MI.
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Juleff, Nicholas Dylan. "Interactions of foot-and-mouth disease virus with cells in organised lymphoid tissue influence innate and adaptive immune responses." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4256.
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Foot-and-mouth disease virus (FMDV) is one of the most contagious viruses of animals and is recognised as the most important constraint to international trade in animals and animal products. Two fundamental problems remain to be understood before more effective control measures can be put in place. These problems are the FMDV „carrier state‟ and the short duration of immunity after vaccination which contrasts with prolonged immunity after natural infection. The aim of this thesis was to study the interaction between FDMV and cells in lymphoid tissue in the natural bovine host, in order to improve our understanding of the protective immune response. Using laser capture microdissection in combination with quantitative real-time reverse transcription polymerase chain reaction, immunohistochemical analysis and corroborated by in situ hybridization, it is shown that FMDV locates rapidly to, and is maintained in, the light zone of germinal centres following primary infection of naïve cattle. Maintenance of non-replicating FMDV in these sites may represent a source of persisting infectious virus and also contribute to the generation of long-lasting antibody responses against neutralising epitopes of the virus. The role of T-lymphocyte subsets in recovery from FMDV infection in calves was investigated by administering subset-specific mouse monoclonal antibodies. Depletion of circulating CD4+ or WC1+ γδ T cells was achieved for a period extending from before challenge to after resolution of viraemia and peak clinical signs, whereas CD8+ cell depletion was only partial. Depletion of CD4+ cells was also confirmed by analysis of lymph node biopsies 5 days post-challenge. Depletion with anti-WC1 and anti-CD8 antibodies had no effect on the kinetics of infection, clinical signs and immune responses following FMDV infection. Three of the four CD4+ T-cell-depleted calves failed to generate an antibody response to the non-structural polyprotein 3ABC, but generated a neutralising antibody response similar to that in the controls, including rapid isotype switching to IgG antibody. These data suggest that antibody responses to sites on the surface of the virus capsid are T cell-independent whereas those directed against the non-structural proteins are T cell-dependent. CD4 depletion was found to substantially inhibit antibody responses to the G-H peptide loop VP1135-156 on the viral capsid, indicating that responses to this particular site, which has a more mobile structure than other neutralising sites on the virus capsid, are T cell-dependent. Depletion of CD4+ T cells had no adverse effect on the magnitude or duration of clinical signs or clearance of virus from the circulation. In conclusion, CD4+ T-cell-independent antibody responses play a major role in the resolution of primary infection with FMDV in cattle.
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QUIQUANDON, ISABELLE. "Biopsie des glandes salivaires accessoires et lymphomes : syndrome de gougerot sjogren et lymphomes du malt (mucosa associated lymphoid tissue)." Lille 2, 1990. http://www.theses.fr/1990LIL2M360.
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Doyle, Chloe. "Investigating The Immunology Of Crohn’s Disease." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29965.
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Crohn’s disease is a chronic autoimmune disease characterised by chronic inflammation in the gastrointestinal tract caused by an uncontrolled immune reaction to commensal bacteria. It is steadily increasing in incidence across the globe, especially in young adults. Current treatments act to reduce inflammation but there is no cure. This is because this disease is still poorly understood especially regarding the specific immune cells involved. Defining these cells and their functions could provide critical insights into the causes and progression of this disease and pave the way for therapeutic interventions.
Our group has privileged access to large human intestinal explants from patients undergoing surgery to remove Crohn’s affected tissue. We are also experts in the biology of mononuclear phagocytes, which are key cells in mediating immune tolerance and inflammation and represent an obvious class of cells that may play a role in Crohn’s disease.
Here we have firstly optimised intestinal tissue digestion protocols to extract mononuclear phagocytes (and other immune cells) from fresh human intestinal tissue in a viable and functional state. We then designed and optimised high-parameter flow cytometry panels to comprehensively identify and characterise all known subsets of mononuclear phagocytes as well as innate lymphoid cells, mucosal-associated invariant T cells, natural killer cells and T cells.
We then accurately defined the mononuclear phagocyte subsets present in tissue affected by Crohn’s Disease compared to uninflamed tissue and inflamed non-Crohn’s tissue. We revealed that langerin+ type-2-conventional dendritic cells (cDC2) were significantly reduced in Crohn’s affected ileum. We went on to show that in healthy tissues these cells drove the induction of CD4+ T helper 2 and T helper 17 cells that highly expressed GATA3, RORt and AHR.
Restoration of langerin+ cDC2 in Crohn’s Disease patients may therefore provide a therapeutic avenue to treat this illness.
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Izquierdo-Roman, Alondra. "Localized Mechanical Compression as a Technique for the Modification of Biological Tissue Optical Properties." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/76856.
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Tissue optical clearing aims to increase the penetration depth of near-collimated light in biological tissue to enhance optical diagnostic, therapeutic, and cosmetic procedures. Previous studies have shown the effects of chemical optical clearing on tissue optical properties. Drawbacks associated with chemical clearing include the introduction of potentially toxic exogenous chemicals into the tissue, poor site targeting, as well as slow transport of the chemicals through tissue. Thus, alternative clearing methods have been investigated. Mechanical compression is one such alternative tissue optical clearing technique. The mechanisms of action of mechanical compression may be similar to those of chemical clearing, though they have yet to be investigated systematically. This research describes the design and execution of a number of procedures useful for the quantification of the tissue optical clearing effects of localized mechanical compression. The first experimental chapter presents the effects of compression on image resolution and contrast of a target imaged through ex vivo biological tissue. It was found that mechanical optical clearing allowed recovery of smaller targets at higher contrast sensitivity when compared to chemical clearing. Also, thickness-independent tissue clearing effects were observed. In the second experimental chapter, dynamic changes in tissue optical properties, namely scattering and absorption coefficients (?s' and ?a, respectively) were monitored during a controlled compression protocol using different indentation geometries. A reduction in ?s' and ?a was evident for all indentation geometries, with greater changes occurring with smaller surface area. Results indicate that localized mechanical compression may be harnessed as a minimally-invasive tissue optical clearing technique.<br>Master of Science
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Yadav, Nitin. "In Vivo characterization of Epileptic Tissue with Optical Spectroscopy." FIU Digital Commons, 2012. http://digitalcommons.fiu.edu/etd/728.
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For children with intractable seizures, surgical removal of epileptic foci, if identifiable and feasible, can be an effective way to reduce or eliminate seizures. The success of this type of surgery strongly hinges upon the ability to identify and demarcate those epileptic foci. The ultimate goal of this research project is to develop an effective technology for detection of unique in vivo pathophysiological characteristics of epileptic cortex and, subsequently, to use this technology to guide epilepsy surgery intraoperatively. In this PhD dissertation the feasibility of using optical spectroscopy to identify unique in vivo pathophysiological characteristics of epileptic cortex was evaluated and proven using the data collected from children undergoing epilepsy surgery.
In this first in vivo human study, static diffuse reflectance and fluorescence spectra were measured from the epileptic cortex, defined by intraoperative ECoG, and its surrounding tissue from pediatric patients undergoing epilepsy surgery. When feasible, biopsy samples were taken from the investigated sites for the subsequent histological analysis. Using the histological data as the gold standard, spectral data was analyzed with statistical tools. The results of the analysis show that static diffuse reflectance spectroscopy and its combination with static fluorescence spectroscopy can be used to effectively differentiate between epileptic cortex with histopathological abnormalities and normal cortex in vivo with a high degree of accuracy.
To maximize the efficiency of optical spectroscopy in detecting and localizing epileptic cortex intraoperatively, the static system was upgraded to investigate histopathological abnormalities deep within the epileptic cortex, as well as to detect unique temporal pathophysiological characteristics of epileptic cortex. Detection of deep abnormalities within the epileptic cortex prompted a redesign of the fiberoptic probe. A mechanical probe holder was also designed and constructed to maintain the probe contact pressure and contact point during the time dependent measurements. The dynamic diffuse reflectance spectroscopy system was used to characterize in vivo pediatric epileptic cortex. The results of the study show that some unique wavelength dependent temporal characteristics (e.g., multiple horizontal bands in the correlation coefficient map g(λref = 800 nm, λcomp,t)) can be found in the time dependent recordings of diffuse reflectance spectra from epileptic cortex defined by ECoG.