Academic literature on the topic 'Platelets Indices'
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Journal articles on the topic "Platelets Indices"
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Anil, Kumar, Bharti Pranav, and Mishra Asim. "A Prospective Study of Platelet Indices and Their Interpretation in Thrombocytopenia at a Tertiary Care Hospital." International Journal of Pharmaceutical and Clinical Research 15, no. 10 (2023): 1334–39. https://doi.org/10.5281/zenodo.11288767.
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<strong>Background:</strong> Thrombocytopenia is defined as a platelet count of <150 × 10<sup>9</sup>/L, although patients with a platelet count >50 × 10<sup>9</sup>/L are usually asymptomatic. Severe spontaneous bleeding is rare in thrombocytopenia. It is more common when the platelet count is <20 × 10<sup>9</sup>/L, and particularly when <10 × 10<sup>9</sup>/L. <strong>Aims and Objectives:</strong> The present study was conducted to evaluate platelet indices and their interpretation in thrombocytopenia in a tertiary care hospital. <strong>Materials and Methods: </strong>An observational, prospective study was conducted on 100 patients with a platelet count <150×10<sup>3</sup>/μL were enrolled as a study group, along with another set of 50 healthy control samples with a platelet count ≥150×10<sup>3</sup>/μL were included in the study. Four ml of venous blood was collected in an EDTA vacutainer. An auto-analyzer was used for the evaluation of the hematological profile. After evaluation of the hematological profile, 50 patients with a platelet count <150×10<sup>3</sup>/μL were divided into each Group 1 (hyperdestruction of platelets) and Group 2 (decreased production of platelets) based on clinical and hematological details. <strong>Results:</strong> A total of 100 thrombocytopenia cases and 50 controls were analyzed. The mean age of the patients was 42.65±16.37 year in hypo‑productive, 29.45±12.74 years in hyper‑destructive, and 34.50±11.68 year in control years respectively. The mean platelet count (10^3 µL) in the hypo‑productive, hyper‑destructive and healthy control groups was 82.50±33.25, 65.82±36.42, and 225.91±68.41 (10^3 µL) , respectively. The mean MPV in the hypo‑productive, hyper‑destructive and healthy control groups was 10.65±1.94 fl, 12.35±1.53 fl and 9.64±1.68 fl respectively. The mean PCT in the hypo‑productive, hyper‑destructive and healthy control groups was 0.08±0.06 %, 0.09±0.05% and 0.22±0.06% respectively. <strong>Conclusion:</strong> All the platelet indices were higher in hyper‑destructive thrombocytopenia as compared to hypo‑productive thrombocytopenia except platelet count, whereas PCT in healthy controls was higher than that in hypo‑productive and hyper‑destructive thrombocytopenia patients.
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Koppalkar, Rachana, K. P. Athira, and Safeena Amber. "Significance of impedance based platelet parameters in prediction of acute coronary syndromes." Panacea Journal of Medical Sciences 14, no. 3 (2024): 724–28. https://doi.org/10.18231/j.pjms.2024.129.
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The primary cause of coronary artery disease is atherosclerosis and its complications. Formation of coronary thrombus and initiation of atherosclerotic lesions are significantly influenced by platelets and their activity. Compared to smaller platelets, giant platelets have a larger potential thrombotic ability and are more metabolically and enzymatically active. The objective of the current research is to determine the significance and role of platelet indices by comparing the values in patients with Acute Coronary Syndrome (ACS) to those in healthy controls. This prospective case-control study was carried out in a tertiary care centre with 100 cases and 100 controls for 6 months. Blood samples were taken when the patient was admitted. Platelet indices were measured within 30 minutes of blood collection using an automated haematology analyzer.Platelet indices such as Mean platelet volume, Platelet distribution width and Platelet large cell ratio were substantially greater in patients with ACS than in healthy controls. Platelet count and Plateletcrit showed lower level in ACS patients with respect to controls.Platelet indices measurement would be beneficial in estimating those patients at greater risk for developing ACS in the future.
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Cho, Min Soon, Justin Bottsford-Miller, Hernan G. Vasquez, et al. "Platelets increase the proliferation of ovarian cancer cells." Blood 120, no. 24 (2012): 4869–72. http://dx.doi.org/10.1182/blood-2012-06-438598.
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Abstract Platelets promote metastasis and angiogenesis, but their effect on tumor cell growth is uncertain. Here we report a direct proliferative effect of platelets on cancer cells both in vitro and in vivo. Incubation of platelets with ovarian cancer cells from murine (ID8 and 2C6) or human (SKOV3 and OVCAR5) origin increased cell proliferation. The proliferative effect of platelets was not dependent on direct contact with cancer cells, and preincubation of platelets with blocking antibodies against platelet adhesion molecules did not alter their effect on cancer cells. The proliferative effect of platelets was reduced by fixing platelets with paraformaldehyde, preincubating platelets with a TGF-β1–blocking antibody, or reducing expression of TGF-βR1 receptor on cancer cells with siRNA. Infusing platelets into mice with orthotopic ovarian tumors significantly increased the proliferation indices in these tumors. Ovarian cancer patients with thrombocytosis had higher tumor proliferation indices compared with patients with normal platelet counts.
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Vaiyakkani, Govardhini, Sridhar Sundaravadanam, Gokulakrishnan Harikrishnan, and Priyatharicini Anandasekar. "Assessment of platelets in patients with pulmonary hypertension." International Journal of Advances in Medicine 8, no. 8 (2021): 1038. http://dx.doi.org/10.18203/2349-3933.ijam20212821.
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Background: Pulmonary hypertension (PH) occurs due to end result of multifactorial etiology causing significant morbidity and mortality. Platelets are observed to be activated during initiation and progression of disease, platelets indices used as surrogate markers for platelet activation was used in current study to investigate effect of PH on platelets and correlate it with severity of PH.Methods: 104 patients with PH were grouped according to WHO classification depending upon etiology. Blood samples of patients from all groups were collected and investigated for platelet indices, peripheral smear, bleeding time, clotting time and echocardiography assessment to know the severity of pulmonary hypertension. Patients were reviewed after 2 months of appropriate treatment.Results: Prevalence of PH due to chronic lung disease (48.1%) was the most common observation. Thrombocyte count was decreased significantly in all groups of PH with p<0.01. MPV, PDW, P-LCR (platelet-large cell ratio) were observed to be increased with increasing severity for PH. Significant correlation p=0.01 indicated that platelet indices were altered with treatment for PH.Conclusions: Significant reduction was observed in platelet count with increase in platelet indices can be correlated with severity of PH. Hence in rural areas without echo cardiogram facilities, platelet indices can be considered as surrogate markers for early referral of patients to higher centers for further management of PH.
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Karagöz, Bülent, İlker Sücüllü, Özkan Sayan, et al. "Platelet indices in patients with colorectal cancer." Open Medicine 5, no. 3 (2010): 365–68. http://dx.doi.org/10.2478/s11536-009-0077-7.
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AbstractThe interaction between cancer cells and platelets has been known for a long time. Although platelet indices have been also investigated in several clinical settings, it has not been exactly demonstrated in cancer patients. We investigated platelet indices in colorectal cancer patients and compared with healthy subjects. Two hundred and twenty-one colorectal cancer patients and 110 healthy subjects were enrolled into the retrospective study. Data were obtained from computerized medical records of our hospital. Medical record review was performed for all patients regarding thrombocyte indices. Platelet count (325.000/mm3 ± 265.000/mm3 vs 267.000/mm3 ± 67.000/mm3; p=0.025; respectively) and plateletcrit (Pct) (0.25% ± 0.10 vs 0.21 ± 0.05; p<0.001; respectively) were increased in patients compared with healthy subjects while mean platelet volume (MPV) and platelet distribution width (PDW) were similar. The platelet indices were not related to existence of metastasis or acute abdomen. Platelet count and Pct, but not MPV and PDW, are elevated in colorectal cancer patients. Future studies that investigate platelet morphology, function, and putative role of platelets in tumorigenesis and metatasis should be established.
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Naina, Harris V. K., and Samar Harris. "Platelet and Red Blood Cell Indices in Harris Platelet Syndrome." Blood 108, no. 11 (2006): 3988. http://dx.doi.org/10.1182/blood.v108.11.3988.3988.
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Abstract Inherited giant platelet disorders are a group of rare disorders characterized by thrombocytopenia, giant platelets and variable bleeding symptoms. Naina et al., described a new giant platelet disorder called Harris Platelet Syndrome (HPS), the most common inherited giant platelet disorder occurring in up to one third of blood donors from north eastern part of Indian subcontinent. HPS is characterized by an autosomal dominant mode of inheritance with normal to severe thrombocytopenia (less than 50x109/L), giant platelets (mean platelet volume more than 10fL) and absent bleeding symptoms with normal platelet aggregation studies. Occasionally abnormalities in red blood cell morphology have been associated with certain giant platelet disorders such as stomatocytosis in Mediterranean Macrothrmboctopenia, dyserythropoiesis in GATA 1 associated macrothrombocytopenia and thalassemia, in X Linked Thrombocytopenia Thalassemia (XLTT). This study was undertaken to analyze the platelet and red blood cell indices in blood donors with Harris Platelet syndrome. A total of 203 blood donors were included in this study, 101 blood donors from northeaster part of India with MPV more than 12fl (normal 7–10fl) and 102 blood donors from southern part of India. Before blood donation, all donors were questioned about a history of bleeding conditions, in either themselves or their relatives. Blood samples were collected in ethylenediaminetetraacetic acid (EDTA). Automated platelet counts were performed using a Coulter STKS (Coulter, Hialeah, Florida) within 2 hours of collection. Peripheral blood smears were examined to confirm thrombocytopenia, giant platelets and red blood cell morphology. There was a significant difference between platelet count (Mean ±SD) 136± 40 Vs 262 ± 53 in southern India (p<0.000). Thirty three donors with HPS had a normal platelet count with MPV more than 12fL. MPV was 13.6±0.13 (range 12 to21.9fL) in donors with HPS and 7.3 ±0.6 (range 6–9.2fl) in southern Indian blood donors. The platelet distribution width (PDW) was 17.4±0.8 in donors with HPS and was 16.38±0.5 in southern India blood donors(p<0.000). Though there was a significant difference between hemoglobin, 13.8 ± 1.0 vs and 14.7± 1.1 (P<0.00), there was no significant difference between RDW, MCV, MCH, MCHC. Peripheral blood smear did not show any obvious red blood cell abnormality, but showed giant platelets and thrombocytopenia. Harris platelet syndrome is associated with normal to severe thrombocytopenia, giant platelets and significant platelet anisocytosis. There was no associated red blood cell abnormalities observed with HPS.
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Ajay, Kumar, Kumar Binay, Kanaujia Binita, and Raza Sahab. "A Retrospective Investigation to Study the Relationship between White Blood Cell Count (WBC), Which is Known Inflammatory Marker and Platelet Count (PLT) and its Parameters." International Journal of Toxicological and Pharmacological Research 13, no. 2 (2023): 76–82. https://doi.org/10.5281/zenodo.11280384.
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<strong>Aim: </strong>The aim of this study was to investigate the relationship between white blood cell count (WBC), which is known inflammatory marker and platelet count (PLT) and its parameters including mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT) and platelet- large cell ratio (P-LCR) in all clinical setting of leukocytosis in children. <strong>Methods: </strong>We performed a retrospective study on the children (2-18 years of age) coming to our laboratory Netaji Subhas Medical College & Hospital, Bihta, Patna, Bihar for the period of 9 months. Total 300 children were evaluated. Out of these,150 children with elevated WBC count (>4000/mm 3) were called as Group 1 and 150 subjects with normal WBC counts and the platelet parameters were included in the study as a control group (Group 2). <strong>Results: </strong>There were 90 males and 70 were females in the present study. Totally (including Group 1 and Group 2 children), 300 complete blood counts were analysed. The mean age of subjects was 11.88 ± 6.647 years for group 1 and 11.37 ± 6.505 years for group 2. There were not statistically significant differences between two groups with respect to age. The result depicts the best cut-off points, sensitivity and specificity of PLT and platelet indices. The sensitivity was highest for platelets at 96.67 and lowest for MPV 32.97 while as specificity was highest for WBC at 94.4 for MPV was 92.22 and lowest for PLT 30.77. <strong>Conclusion: </strong>This study showed that platelet count and platelet distribution width values were significantly high in simple infectious and inflammatory conditions in children but there is no correlation with platetcrit, MPV and P-LCR values. The correlation is low as the sample size is less. There are controversial results with regard to platelet parameters in many studies done on both adult and pediatric population.
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Zeb, Salma, Owais Qaisar, Nazish Babar, Ayesha Sardar, Muhammad Bilal, and Syed Luqman Shuaib. "Significance of Platelets and its Indices in Patients with Dengue Fever." Pakistan Journal of Medical and Health Sciences 17, no. 2 (2023): 475–78. http://dx.doi.org/10.53350/pjmhs2023172475.
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Background: Dengue is a viral infection affecting different parts of the world, particularly the under developed countries including Pakistan. Changes in hematological parameters are frequently observed in dengue viral infection out of which the changes in the structure of platelets and their levels are a predominant factor in dengue viral infection. In view of the foresaid, this study was conducted to find the platelet levels and indices in confirmed cases suffering from dengue fever. Methods: This descriptive cross-sectional study was conducted in Peshawar in a duration of five months from September to December 2022. A total of five hundred patients were screened for dengue viral infection. Blood samples were collected from all suspected dengue infected patients and processed for complete blood count (CBC). Percentage and mean standard deviation were calculated and data were expressed in tables and graphs. Results: Among total suspected patients, one hundred fifty patients were found positive in which highest number of patients were male (65.3%) than female patients (34.7%). The minimum hemoglobin, white blood cells, and platelets were 6.9 g/dl, 2400 g/dl, and 43000 g/dl respectively. Low level of hemoglobin was found in 9.4% patients, 25.3% patients had below normal white blood cell count, and 30.4% patients were observed with less than normal platelet count. Few patients were noted with lower mean platelets volume and plateletcrit than normal. Conclusion: The study showed a significant impact of dengue viral infection on complete blood count. The hemoglobin, WBC, platelets, and platelet indices were potentially affected with dengue viral infection. It is necessary to design a strategy for early diagnosis of dengue infected patients for timely treatment, which can together save patients from severe impact of dengue viral infection such as dengue shock syndrome which could be fatal. Keywords: Dengue viral infection, Hematological parameters, Platelets, Mean Platelets Volume, Plateletcrit, Platelet distributive width.
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Saini, Vandana, Vijaya Vallepu, and Mamta Gupta. "Platelet Counts and Indices Are Altered in Pre-Eclampsia." Annals of Pathology and Laboratory Medicine 7, no. 7 (2020): A361–365. http://dx.doi.org/10.21276/apalm.2830.
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BACKGROUND: Endothelial damage and activation of platelets leading to their increased consumption and increase in production of young platelets by bone marrow is the most common pathophysiology of pre-eclampsia. Thus, fall in platelet count and altered platelet indices may have diagnostic as well as prognostic value in pre-eclampsia. AIM: To evaluate platelet count and platelet indices between pre-eclamptic and normotensive women and to assess their association with severity of pre-eclampsia.
 METHODS: Platelet counts and indices were estimated in 30 normotensive and 30 PE women at 20-24 weeks pregnancy and were repeated after every 4 weeks.
 RESULTS: Mean platelet counts, platelet volume, platelet distribution width, and platelet large cell ratio between pre-eclampsia and normotensive women were significantly altered in PE women and were associated with severity of PE. This alteration of platelet count and indices occurred even before the rise of BP.
 CONCLUSION: All the platelet indices were found to be reliable markers of PE and were found to be increased much earlier than BP. MPV had the maximum sensitivity (96.7%) and specificity (93.3%) and was the most reliable biomarker.
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Hayuningsih, Chakrawati, Leni Lismayanti, and Anna Tjandrawati. "Comparison of Thrombocyte Indices and Immature Platelet between Preeclampsia and Normal Pregnancy." INDONESIAN JOURNAL OF CLINICAL PATHOLOGY AND MEDICAL LABORATORY 30, no. 1 (2023): 54–59. http://dx.doi.org/10.24293/ijcpml.v30i1.2075.
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The primary pathophysiology of preeclampsia is abnormal trophoblast invasion, vasospasm, and endothelial dysfunction occurring, as well as platelet activation, increased platelet consumption, and the stimulation of the release of new platelets, which affects the platelet indices and immature platelets. This study compared the platelet indices (Mean Platelet Volume=MPV, Platelets Distribution Width=PDW, Platelet Large Cell Ratio=PLCR, and Immature Platelet Fraction (IPF) between preeclampsia and normal pregnancy. This research was an unpaired comparative analytic observational study with a cross-sectional design conducted in the Tangerang District General Hospital from February to August 2020. The platelet indices (MPV, PDW, PLCR) and IPF of preeclampsia subjects (n=33) at Tangerang District General Hospital and normal pregnant subjects (n=38) at Annisa Hospital Tangerang were examined using the Sysmex XN-1000 automatic hematology analyzer. Comparative platelet indices and IPF analysis were carried out by independent T-test or Man-Whitney test. Receiver Operating Characteristics (ROC) analysis was performed to obtain the cut-off value of the platelet indices and IPF to differentiate preeclampsia and normal pregnancy. The platelet indices and IPF were significantly higher in preeclampsia. The mean (SD) MPV was 10.86 (0.9) fL and 10. (0.89) fL, p<0.001; PDW 12.7 (8.7-19.1) fL and 10.85 (8.5-15.7) fL, p<0.001; PLCR 31.96 (7.02) % and 25.06 (6.92) %, p<0.001; and IPF 8.50 (3.10-20.40)% and 2.75 (1.2-9.4)%, p<0.001, respectively in preeclampsia and normal pregnancy. ROC analysis showed that an IPF with an AUC of 0.88 (95% confidence interval (CI) 0.78-0.95) with an IPF cut-off value of >6.5% was a good marker, while the MPV cut-off >10.2 fL, AUC 0.75(95% CI 0.63-0.84), PDW cut-off >11.3fL, AUC 0.77 (95%CI 0.65-0.86) and PLCR cut-off >26.1%, AUC 0.76 (95% CI 0.65-0.85) were good enough markers to differentiate preeclampsia from normal pregnancy. Platelet indices and IPF were statistically significantly higher in preeclampsia. The IPF parameter is a good marker, while the platelet indices can be a pretty good marker to distinguish preeclampsia and normal pregnancy. The IPF parameter and platelet indices can be proposed as a routine examination in pregnancy. Changes in IPF and platelet indices can be early signs of preeclampsia or the development of preeclampsia.
Dissertations / Theses on the topic "Platelets Indices"
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Tong, Linda. "Platelet indices and their association with chronic valvular heart disease in Cavalier King Charles spaniels." Thesis, Tong, Linda (2017) Platelet indices and their association with chronic valvular heart disease in Cavalier King Charles spaniels. Masters by Research thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/40806/.
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Chronic valvular heart disease (CVHD) is common in Cavalier King Charles spaniel (CKCS) and has the potential to affect platelet activation or function.
The present study objective was to determine platelet closure time, mean platelet component (MPC) concentration and platelet component distribution width (PCDW) in dogs with subclinical CVHD, and to assess the factors influencing these variables. A second objective was to assess platelet count, MPC concentration, PCDW, mean platelet volume (MPV), platelet volume distribution width (PDW), plateletcrit (PCT), mean platelet mass (MPM) and platelet mass distribution width (PMDW) in CKCS.
Haematological values, closure time, murmur grade and echocardiographic variables were recorded in 89 CKCS. Associations between explanatory variables (sex, age, murmur grade, echocardiographic variables, platelet count, and haematocrit (HCT)) and outcomes (closure time, MPC concentration, and PCDW) were examined using multivariate regression analysis. Platelet indices were compared between CKCS and a group of 39 control dogs (non-CKCS).
A model with 5 variables best explained variation in closure time (R2, 0.74), with greater than 60% of the variance of closure time explained by mitral valve regurgitant jet size. The model of best fit to explain variation in MPC concentration included only platelet count (R2, 0.24). The model of best fit to explain variation in PCDW included platelet count and sex (R2, 0.25). The MPC concentration, MPV, PDW, MPM and PMDW values were significantly higher, and the platelet count, PCT, PCDW and HCT values significantly lower, in the CKCS compared to control dogs.
In the present study, a significant effect of mitral valve regurgitant jet size on closure time was consistent with platelet dysfunction. However, platelet activation, as determined by MPC concentration and PCDW, was not a feature of subclinical CVHD in CKCS.
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Er, Elif [Verfasser]. "Effect of sampling on coagulation variables and effect of submaximal physical exercise on ADVIA2120 platelet activation indices, platelet function, secondary and tertiary hemostasis as well as thrombelastography in healthy dogs / Elif Er." Gießen : Universitätsbibliothek, 2012. http://d-nb.info/1063955629/34.
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Yang, SHI-CHI, and 楊世吉. "To investigate the change of platelet volume indices in long-term platelet aphaeresis donors." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8pb59v.
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碩士<br>中華醫事科技大學<br>醫學檢驗生物技術系碩士班<br>107<br>Blood donors who continue to use long-term donor platelets (Apheresis Platelet; PH) are important sources of medical resources for blood donors to serve patients with cancer and blood diseases. For example, according to the Tainan Blood Center, the annual donation of PH donors is about 36,013 units for hospital patients to use. A general blood test is performed before the donation of the PH to determine whether the conditions for the platelet separation are met. However, after the long-term efforts of these dedicated and selfless donors, whether the bone marrow hematopoietic function will change and whether the blood donated will affect the quality of transfusion efficacy, this issue deserves our attention to the platelet physiology of donors. Changes and donated blood products ensure blood transfusion efficiency as expected.
This study used random sampling and retrospective cross-sectional studies. Thirty patients who received the first blood donation (or no blood donor within 6 months) served as the control group. The PH donors who continued for 1 time/2 weeks were used as the study group, and then divided into 5 groups according to the interval of 1-5 years. Subjects who were examined by the IRB for review were initially included in the study to perform changes in the detection of PVI, and to analyze differences in platelet quality changes in patients with long-lasting continuous donor thrombectomy. Samples of the donated blood samples were left on day 3 and day 5 to analyze the PVI to investigate changes in blood during storage. Statistical analysis was performed with one-way ANOVA (SPSS 18.0), (95% CI, p < 0.05).
The results showed that there was no significant difference in the PVI between the study group and the control group. There was a significant difference between the study group donated 2 unit PH and the control group PVI. In the platelet storage activity, the average platelet count on the fifth day was lower than that on the third day, and the items such as PVI stored on the fifth day were higher than the third day and there was a significant difference.
This study suggests that blood donors should not encourage continuous blood donation for two weeks to ensure the health of the donors and the continued blood donation. It is known that the platelet
yield data is inversely related to MPV during the change of the preservation period, and is still caused by the expansion of platelet cells during storage. It is recommended that the PVI be tested in addition to the pH at the end of the period to support the platelet's yield Quility Control to ensure the patient's blood transfusion quality.
Books on the topic "Platelets Indices"
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Okeke, Peter. Platelet Count and Indices of Mean Platelet Volume, Platelet Distribution Width and Platelet Large Cell Ratio - Is There Any Sex Difference? GRIN Verlag GmbH, 2012.
Find full textBook chapters on the topic "Platelets Indices"
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de Gaetano, Giovanni, Iolanda Santimone, Francesco Gianfagna, Licia Iacoviello, and Chiara Cerletti. "Variability of Platelet Indices and Function: Acquired and Genetic Factors." In Antiplatelet Agents. Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-29423-5_16.
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Priyanka, T., S. Nirupa, Pavithra, and Saravanan. "The Study of Association of Platelet Indices to Hypertensive Disorders of Pregnancy." In Recent Developments in Microbiology, Biotechnology and Pharmaceutical Sciences. CRC Press, 2025. https://doi.org/10.1201/9781003618140-12.
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Blann, Andrew, Gary Moore, and Gavin Knight. "Major haematology parameters and basic techniques." In Haematology. Oxford University Press, 2021. http://dx.doi.org/10.1093/hesc/9780198826095.003.0002.
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This chapter explores certain aspects of haematology, detailing principal haematology tests, such as the full blood count, and basic techniques that are used to define particular indices, such as haemoglobin. It highlights the importance of different anticoagulants and glass or plastic tubes for the different blood tests requested. It also covers major haematology techniques such as spectrometry, microscopy, light scatter, impedance technology, and calibration. The chapter emphasizes the major components of the full blood count, which include the red blood cell indices, the white blood cell indices, and platelets. It describes the differences in the values of the erythrocyte sedimentation rate and plasma viscosity, including the important aspects of the micronutrients iron, vitamin B<sub>12</sub>, folate, and plasma proteins such as transferrin and ferritin.
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Leontiev, Pavlo, Inna Torianyk, and Svitlana Kalinichenko. "PARAMETERS OF BLOOD AND ERYTHROCYTES AS MARKERS OF AGE OF OCCURRENCE OF HEMATOMAS IN LIVING PERSONS." In Modernization of research area: national prospects and European practices. Publishing House “Baltija Publishing”, 2022. http://dx.doi.org/10.30525/978-9934-26-221-0-15.
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The article deals with solution of the scientific-practical task of modern forensic medicine: substantiation for medicolegal assessment of prescription of formation of posttraumatic sub- and epidural haemorrhages in living persons. The purpose: to determine the age of hematoma in living persons by the parameters of functional changes in the blood system and erythrocyte hematopoiesis. Methodology of the study is based on general research methods of analysis of cytological results the haematological indices, which were the most available and effective ones in accelerated diagnosis of the prescription of appearance of posttrtaumatic sub- and epidural haemorrhages, were studied by means of including methods of examination of aggregate properties of blood cells (superficial cytoarchitectonics of erythrocytes) and coagulation haemostasis parameters (fibrinogen, prothrombin, thrombocytes) into the methodological scheme. Results. In victims with epi- and subdural hematomas, changes in blood parameters (hemoglobin, erythrocytes, platelets, prothrombin, fibrinogen) were phase in nature. Against the background of stable control group figures, the number of erythrocytes decreased from the 1st to the 6th day with further rise (12th – 21st days of observations) and stabilization for 90 days. The increase in hemoglobin occurred from the 1st day of observation to the 21st day and ended with a digital plateau on the 90th day of the study. The parameters of coagulation hemostasis (fibrinogen, prothrombin) had similar digital profiles with outbreaks of rises on the 1st day of observation and a decrease in indicators on the 6th and 12th days, respectively. The increase in platelet count was gradual until the 12th day of observation. The erythrocyte link of the blood reacted to the occurrence of epi- and subdural hematomas by the appearance of coordination phenomena and changes in the surface membrane of cells with the development (in the approximate and distant delayed periods – 3-21 days) of expressive dispersion of forms from ovals, spherocytes to echino-. Gender-age dependence was not observed in the groups. Practical implications. The obtained data fully contribute to a reasonable solution of an important practical issue: determining the role of functional parameters of blood, its erythrocyte population in the development of unified programs / algorithms to determine diagnostic premortem markers of hematoma in the face of craniocerebral injuries. Value/originality lies in the possibility of applying the results of the work in modern diagnostic algorithms for the prescription of hematomas.
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Abishek Chakkaravarthi, M., and Marry Lilly. "Immuno-Suppression: Advances and Challenges in Dengue – A Hospital Based Cross Sectional Study." In Mosquito-Borne Tropical Diseases [Working Title]. IntechOpen, 2025. https://doi.org/10.5772/intechopen.1006613.
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People who are immune-suppressed have less ability to recover and possess weaker immune systems after dengue fever. Early diagnosis and treatment reduce the mortality. With the approval of the Ethical Committee, 70 dengue fever cases were selected from Balaji Medical College Hospital, Chennai, Tamil Nadu, India. Under aseptic precautions, venous blood was collected with minimal stasis using dry and sterile disposable syringe and needle. The analyzer followed the sheath fluid impedance principle to calculate total RBC counts and platelet counts. The laser flow cytometry principle was used to calculate the total WBC counts. Calculations were done using SPSS21 and Microsoft Excel. One-way analysis of variance (ANOVA) with post-hoc test, Tukey’s honest significance difference tests, Spearman’s rho correlation, and chi-square test of independence were used to compare more than two independent samples. A T-test for single samples was done. P of 0.05 (a = 0.05) was considered to be statistically significant. About 70 cases of fever of various causes were studied. Serum ferritin and platelet-derived parameters such as mean platelet volume (MPV), platelet distribution width (PDW), and platelet count were studied, and the significance in relation between diagnosis and age in years was found. Significant changes were observed in PWD. Patients who had low platelet counts commonly presented with high ferritin (p = .036). Trends in platelet indices have been of continuous interest as markers. The relationship between age, sex, diagnosis, serumferritin, platelet distribution width (PDW), and platelet count was studied in 70 cases of non-structural protein NS1serology positive dengue. Some variables showed statistically significant correlations.
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Reinhard, Matthias, Thomas Jarchau, Kathrin Reinhard, and Ulrich Walter. "VASP." In Guidebook to the Cytoskeletal and Motor Proteins. Oxford University PressOxford, 1999. http://dx.doi.org/10.1093/oso/9780198599579.003.0054.
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Abstract VASP, a praline-rich protein substrate of both cAMP- and cGMP-dependent protein kinases, is expressed in most mammalian cell types and tissues. Particularly high VASP levels are detected in human platelets. In cultured cells, VASP is associated with focal adhesions, cell-cell contacts, microfilaments, and highly dynamic membrane regions such as the leading edge. From in vitro binding data VASP has been suggested to link profilin to zyxin, vinculin, and the Listeria spp. surface protein ActA. Functional evidence indicates that VASP is a crucial factor involved in the enhancement of actin filament formation.
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Green, Siva Ranganathan, Subashini Subramanian, and Lokesh Shanmugam. "Determining the Relationship between Platelet Indices and Microvascular Complications in Type 2 Diabetic Patients." In Recent Developments in Medicine and Medical Research Vol. 6. Book Publisher International (a part of SCIENCEDOMAIN International), 2021. http://dx.doi.org/10.9734/bpi/rdmmr/v6/5119f.
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Bakovic Darija, Palada Ivan, and Dujic Zeljko. "Apnea Diving." In Biomedical and Health Research. IOS Press, 2010. https://doi.org/10.3233/978-1-60750-497-9-431.
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Men and women have been diving for thousands of years to gather a variety of products, including food, sponges, and pearls, to conduct salvage and military operations, and to explore. In 1911, one of the first freediving competitions was held when a Greek fisherman, Yorgos Haggi Statti, was offered a few dollars to dive and to rescue the anchor of an Italian ship which had become stuck in the Aegean Sea. The Italian ship was set free and Yorgos became known as the &ldquo;father of freediving&rdquo;. After World War II, breath hold diving became an international sport where athletes test the human limits of time, depth and distance. Exposure to excessive depths, though, can be very dangerous and cause a collapse of the lungs, cardiac arrest, blackouts, decompression sickness and, at worst, death. Whatever the reason for breath hold diving, its success depends on how a diver tolerates the physiological stress related to the depth and duration of dive. The human body has several adaptations under diving conditions, which stem from the mammalian diving reflex. These adaptations enable the human body to endure depth and lack of oxygen far beyond what would be possible without the reflex. Human diving response involves bradycardia, vasoconstriction of selected vascular beds with increase in blood pressure, changes in cardiac output and spleen contraction. Variety of studies frequently discussed parts of diving response. However, the concept of spleen contraction has recently been described as a property of diving response. The spleen serves as a dynamic blood cell reservoir which can be released into systemic circulation during exercise, diving or intermittent hypoxia. Since contraction of the spleen increases hemoglobin and hematocrit circulating in blood, than the O2transport will also be enhanced. In humans, the rapidity of spleen contraction indicates that the initial stimulation is likely neural in origin, but contraction may be sustained throughout the dive by circulating catecholamines released from the adrenal gland. Leucocytes and platelets accumulate in the human spleen to a much greater extent than erythrocytes, accounting for approximately 40% of both body populations. The destiny of these two populations during apnea induced spleen contraction is also the aim of our chapter.
Conference papers on the topic "Platelets Indices"
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Beletić, Anđjelo, Josipa Kuleš, Ivana Rubić I, Filipović Milica Kovačević, and Vladimir Mrljak. "Serum, Saliva, and Liver Proteome Indices Associated with Platelet Biology during Inflammatory Conditions in Different Animal Species." In Socratic Lectures 8. University of Lubljana Press, 2023. http://dx.doi.org/10.55295/psl.2023.i1.
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The understanding of platelet biology stepped out of the (patho)physiology of hemostasis long ago. Currently, platelets are acknowledged as effective sentinels against pathogens and powerful regulators of inflammatory processes. While accomplishing these tasks, their structural and physiological features undergo constant changes, often associated with the proteomics indices in the tissues and biofluids. Assessing these associations in different animal species provides a substantial comparative benefit. Nevertheless, the sine qua non for the reliable interpretation of the obtained data is a comprehensive understanding of the applied analytical and bioinformatics methods. Keywords: Tissue; Body fluids; Proteomics; Platelet biology; Animals; Infections
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Costa, PA. "FRAÇÃO DE PLAQUETAS IMATURAS (IPF): UMA REVISÃO DA LITERATURA." In Resumos do 54º Congresso Brasileiro de Patologia Clínica/Medicina Laboratorial. Zeppelini Editorial e Comunicação, 2022. http://dx.doi.org/10.5327/1516-3180.140s1.5646.
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Objetivo: O objetivo deste trabalho foi pesquisar a utilidade diagnóstica das PRs, por meio do parâmetro de fração de plaquetas imaturas (IPF) na rotina médica, e suas limitações, além das perspectivas futuras para seu uso. Método: Foi realizada uma pesquisa bibliográfica em bases de dados confiáveis: Medline, US. National Library of Medicine National Institutes of Health, USA (PubMed), Scientific Eletronic Library Online (SciELO Brazil) e Biblioteca Regional de Medicina, Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde (BIREME), utilizando os descritores platelet indices, immature platelet fraction e reticulated platelets. Conclusão: Por meio desta revisão bibliográfica, conclui-se que a fração de plaquetas imaturas é um promissor parâmetro laboratorial para identificar a etiologia da trombocitopenia (consumo periférico ou falha medular). Embora novos estudos precisem aprofundar o conhecimento e a segurança do uso do IPF, este parâmetro mostra-se útil para o auxílio diagnóstico e o acompanhamento terapêutico de uma série de patologias associadas à trombocitopenia, como púrpura trombocitopênica e acompanhamento de pacientes transplantados e pacientes com risco de sepse. Referências: 1. Adly AAM et al. Evaluation of the immature platelet fraction in the diagnosis and prognosis of childhood immune thrombocytopenia. Platelets. 2015; 26(7): 645-50. 2. Ancliff P. Trigger factors for prophylactic platelet transfusion. Blood Reviews. 1998; 12(4): 234-38. 3. Ault KA et al. The significance of platelets with increased RNA content (reticulated platelets): a measure of the rate of thrombopoiesis. Am J Clin Pathol. 1992; 98(6): 637-46
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Drouin, J., D. Lillicrap, A. R. Giles, C. A. Izaguirre, S. Windsor, and H. Hoogendorn. "ABSENCE OF A BLEEDING TENDENCY IN SEVERE ACQUIRED DEFICIENCY OF PLASMA VON WILLEBRAND FACTOR (vWf)/F. VIII WITH NORMAL PLATELET vWf/F. VIII INDICES." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644116.
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A 67 year old male with IgA myeloma has been investigated for a severe deficiency of plasma vWf/F. VIII but normal platelet vWf/F. VIII. He has no personal history nor family history of bleeding problems. He was initially investigated for a prolonged APTT of 43 secs. (25-40) obtained in a preoperative clotting screen. During this investigation he was found to have IgA myeloma. In retrospect, an APTT prior to uneventful coronary artery bypass surgery two years previously had been prolonged. Routine investigation has shown that platelet count and bleeding time have been repeatedly normal. Plasma F. VIII:C is 0.08 u/ml., F. VIII:Cag 0.07 u/ml., vWf:Ag 0.05 u/ml. and ristocetin cofactor 0.05 u/ml. In contrast, platelet values for vWf:Ag of 53 units/109 platelets and F. VIII:Cag of 176 units/109 platelets are within the normal ranges for our laboratory. The platelet lysate vWf multimer pattern is also normal. Patient's plasma shows inhibitory activity against vWf:Ag but not against either F. VIII:C or ristocetin cofactor activity. When patient plasma is incubated for 60 mins at 37°C with vWf and analysed by crossed Immunoelectrophoresis (CIE) for vWf:Ag, a double arc precipitin line is observed with marked retardation of the first arc. A similar vWf:Ag CIE double precipitin arc is seen following the infusion of cryoprecipitate. T 1/2 for F. VIII:C and vWf:Ag are both reduced following the infusion of cryoprecipitate - F. VIII:C 2 hrs, vWf:Ag 3 trs. No secondary rise in F. VIIIrC is seen at 24 hrs. Despite severe deficiency of plasma vWf/F. VIII, this man does not have a clinical bleeding tendency. We postulate that his plasma vWf/F. VIII deficiency is the result of complexing of his IgA myeloma protein with vWf, resulting in premature clearance of the vWf/F. VIII complex. This case further emphasizes the role of platelet associated coagulation factors in maintaining normal haemostasis.
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Wachtfogel, Yanina T., Yizhar Floman, Meir Liebergall, Robert W. Colman, and Amiram Eldor. "PLATELET ALPHA2-ADRENERGIC RECEPTOR ABNORMALITIES IN PATIENTS WITH IDIOPATHK: SCOLIOSIS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644567.
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Idiopathic scoliosis is a genetic multisystem disease involving skeletal, biochemical, central nervous svstem, muscle and blood platelet abnormalities. Platelets of patients with idiopathic scoliosis have been shown to have decreased adenosine diphosphate and epinephrine-induced aggregation. Similarities between the contractile protein system of platelets and muscle have made the platelet a popular model for certain aspects of muscle physiology. This study confirmed that 64% of the patient platelets tested exhibited a significantly decreased sensitivity to aggregation bv epinephrine. In seven of the eleven patients studied, epinephrine induced aggregation was markedly decreased, i.e., the threshold of agonist was markedly elevated ≥11 uM). The geometric mean concentration of epinephrine required to produce complete second-wave aggregation in idiopathic scoliosis patients was 8μM. as compared to a control concentration of luM. We therefore examined the platelet alpha2-adrenergic receptors of 17 patients with idiopathic scoliosis bv measuring ligand binding using the selective antagonist, methyl yohimbine. Platelets from healthv individuals had 185 ± 16 sites per platelet with a Kd of 1.90 ± 0.32 nM, while patients with idiopathic scoliosis had 54 ± 22 sites per platelet with a of 1.02 ± 0.03 nM. The number of binding sites per platelet in idiopathic scoliosis patients were significantly decreased (p < 0.05) as compared to controls , while the was not significantly different (p > 0.05) between the two groups. Seven of these patients exhibited a significant decrease (p < 0.05) in the number of alpha2-adrenergic receptors on their platelets while the binding in 7 additional patients was undetectable.Three patients exhibited normal receptor number and affinity as compared to normal individuals. This study indicates a profound alteration in the number and function of the alpha2-adrenergic receptors in platelets of patients with idiopathic scoliosis and indicates the functional heterogeneity of the receptor disorder. Further investigation of platelet abnormalities may give insight into the putative muscle defects.
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Douglas, Jessie T., G. D. O. Lowe, R. Balendra, et al. "PROGNOSTIC SIGNIFICANCE OF HAEMOSTATIC VARIABLES IN ACUTE STROKE." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643827.
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Acute stroke is normally the result of thromboembolism. Such thromboemboli form and extend by the interaction of platelets and fibrin and elicit a fibrinolytic response. Hence laboratory indices of platelet activation, thrombin formation and plasmin formation may be related to thrombus size and progression, and hence to clinical outcome, ie disability and death. We studied 100 patients with acute paretic stroke and followed them for 1 year. Plasma levels of betathromboglobulin (BTG), fibrinogen, fibrinopeptide A (FPA), fibrin(ogen) fragment BB15-42, serum fragment E, high molecular weight cross-linked fibrin degradation products (X-L FDP) D-dimer, total and tissue plasminogen activator activity, tissue plasminogen activator inhibition and serum fibrin(ogen) degradation products (FDP) were related to death and functional recovery in the 1 year follow up period. The levels of BTG, fibrinogen, FPA, BB15-42, tissue plasminogen activator inhibition and serum fragment E were significantly higher on the first day following stroke, in patients who subsequently died within 1 year when compared to patients who survived. Lowered levels of fibrin plate lysis area as well as raised tPA activity, X-L FDP and D-dimer levels did not achieve significance in patients who subsequently died. In the patients who survived only increased BB15-42 and X-L FDP levels were predictive of functional dependence when compared to patients who became independent. Increased fibrinogen, FPA and fibrin plate lysis area, fragment E and tPA activity and reduced D-dimer did not achieve significance in patients with greater disability when compared to patients with minimal disability. We conclude that several measures of activation of haemostasis are predictive of death in the year following stroke, but only BB15-42 and X-L FDP predict disability in survivors.
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Kim, M. C., C. S. Lee, and C. J. Kim. "Analysis of Volumetric Residence Time of Blood Elements in Stenosed Arteries." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-42840.
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Blood flow in arteries is known to be closely related to atherosclerosis. Presence of recirculation zones, and low, high, and oscillatory wall shear stresses have been suggested to be important fluid dynamic factors causing development and progress of atherosclerosis. Our study was motivated to develop fluid mechanical indices between residence time of blood particles in arteries and atherosclerosis. In rigid models of stenosed arteries with 75% area reduction, trajectories of blood particles were numerically computed and used to determine local volumetric residence time (VRT) of platelets. The motion of particles in the model artery was computed by considering viscous drag forces between blood particles and presolved transient flow field from computational fluid dynamics (CFD). Many cardiac cycles were considered in the computation to reflect temporally accumulative characteristics of VRT in the recirculation zones. Our results showed that VRT in the recirculation zone was relatively low in the first cardiac cycle. However it increased in the subsequent cycles as more particles were trapped in the same zone. The results suggested that VRT contour calculated in the present study would be an effective indicator of the presence of atherosclerosis.
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Modderman, P. W., J. G. Huisman, J. A. van Mourik, A. E. G. Kr, and v. d. Borne. "PLATELET ACTIVATION INDUCED BY A MONOCLONAL ANTIBODY AGAINST THE PLATELET GP Ilb/IIIa COMPLEX." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643514.
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A receptor for fibrinogen on the platelet GP Ila/lIIb complex is induced by ADP, thrombin and other agonists. To study functional domains on GP Ilb/IIIa, the effects of anti-GP Ilb/IIIa monoclonal antibodies (Mab’s) on platelet function were determined. One of these Mab’s, 6C9, induced platelet aggregation. The antibody binds to the intact GP Ilb/IIIa complex only, not to free GP lib or free GP Ilia. Its epitope is different from that of C17, a Mab that inhibits ADP-induced fibrinogen binding and platelet aggregation. 6C9 induces fibrinogen-mediated aggregation rather than agglutination since 6C9-induced platelet interactions were blocked by treatments that also inhibited the effects of ADP etc., without inhibiting binding of 6C9 itself. 6C9 induces binding of 125I-fibrinogen (35.000 ± 7.300 molecules/platelet, Kd = 1.3 ± 0.4 µM) to unstirred platelets. Binding of fibrinogen was 60 to 80% inhibited by apyrase, which indicates that 6C9-induced fibrinogen binding is largely mediated via ADP released from platelets. In addition, 6C9 induced aggregation of platelets in the absence of extracellular fibrinogen. Mediation of this process by platelet fibrinogen or other a-granule proteins, released upon activation by 6C9, was implicated by the finding that aggregation of washed platelets, but not of platelets to which fibrinogen was added, could be blocked by PGI2. Platelet release was also assessed directly by measuring β-thromboglobulin (α-granules) and (14C) serotonin (dense granules) in the medium of unstirred platelets incubated with 6C9. F(ab')2 fragments of 6C9 only aggregated platelets in the presence of fibrinogen and did not release (14C) serotonin. Moreover, release induced by intact 6C9 was inhibited by anti-GP Ilb/IIIa Mab C17 but not by C17 F(ab’)2, although the latter inhibited ADP-induced platelet aggregation. These data indicate that binding of antibodies to specific sites on GP Ilb/IIIa may induce Fc-dependent platelet activation.This study was supported by the Foundation for Medical Research MEDIGON (grant no. 900-526-057.
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Janssens, W. J., and J. M. Van Nueten. "VASOCONSTRICTOR EFFECTS OF AGGREGATING PLATELETS IN RABBIT PULMONARY ARTERIES WITH AND WITHOUT ENDOTHELIUM." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643354.
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The aim of the present experiments was to investigate the modulatory role of the endothelium on vasoconstrictions induced by aggregating platelets. Rings of rabbit pulmonary arteries were mounted for isometric tension recording. The presence or absence of the endothelium was confirmed using acetylcholine-induced relaxations. All contractions were expressed as percentage of a K+-induced (100 mM) contraction. Thrombin was administered to the preparations at 0.5 NIH units/ml. At this concentration the enzyme caused no or only very small contractions, but apparently induced maximal platelet activation in this experimental setting. Cumulative administration of rat platelets in the presence of thrombin caused contractions of the arteries. These contractions occurred at lower platelet amounts and were larger in endothelium-deprived rings than in preparations with intact endothelium. This indicates that mediators released from aggregating platelets cause contraction of the vascular smooth muscle cells which are attenuated by (a) factor(s) released from the endothelium. Platelet-induced contractions were dose-dependently inhibited and finally abolished by the S2-serotonergic antagonist ketanserin and inhibited to a lesser extent by the thromboxane A2 antagonist BM-13177. This indicates that serotonin, and to a lesser extent thromboxane A2, are the mediators of platelet-induced contractions and that mutual amplification of their vasoconstrictor effect may occur. Serotonin-induced contractions of pulmonary artery rings occurred at lower concentrations and were larger in endothelium-deprived preparations indicating that the endothelium derived factor(s) attenuating platelet-induced contraction may be released upon stimulation of the endothelium by serotonin. The pA2-value of ketanserin against serotonin-induced contractions was similar in endothelium-deprived preparations and preparations with intact endothelium. This indicates that the stimulating effect of serotonin on the endothelium is not mediated by the S2-serotonergic mechanism responsible for vascular smooth muscle contractions.
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Hlapčić, Iva, Marija Grdić Rajković, Andrea Hulina Tomašković, et al. "Platelet indices as inflammatory markers in stable COPD." In ERS International Congress 2019 abstracts. European Respiratory Society, 2019. http://dx.doi.org/10.1183/13993003.congress-2019.pa5205.
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Akbar, Huzoor, David Wallace, and Khursheed Anwer. "HUMAN PLATELET ACTIVATION BY BACTERIAL PHOSPHOLIPASE C: MECHANISM OF INHIBITION BY FLURAZEPAM." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643442.
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We have shown earlier that flurazepam inhibits human platelet aggregation and serotonin secretion induced by bacterial phospholipase C (BPLC, Thromb. Res. 38, 361-374, 1985). This study was conducted to examine the mechanism(s) of inhibitory action of flurazepam. Only 15 uM and 11 uM flurazepam were required to inhibit platelet aggregation and serotonin secretion by 50%. In a platelet free system, BPLC hydrolyzed 14C-phosphatidylcholine (14C-PC> in a time- and concentration-dependent manner in the presence of calcium ions. Flurazepam had no effect on BPLC-induced hydrolysis of 14C-PC. Incubation of 14C-arachidonic acid labelled platelets with BPLC produced diacylglycerol(DAG) in a time- and concentration-dependent manner. Flurazepam did not inhibit DAG production by BPLC. However, prostaglandin E1 and paranitrophenolphosphorylcholine inhibited DAG production by 20% and 75% respectively. Platelet cytosolic fraction,containing phosphatidylinositol-specific PLC (PI-PLC), hydrolyzed 3H -phosphatidylinositol (3H-PI) in a concentration-dependent manner. Flurazepam did not inhibit hydrolysis:of 3H-PI by PI-PLC. BPLC caused phosphorylation of 47,000 Dalton protein (P47) in 32P-labelled platelets. Flurazepam did not inhibit phosphorylation of P47 in the first five minutes of incubation. However, flurazapam completely blocked phosphorylation of P47 by seven minutes. In Other experiments, flurazepam inhibited platelet aggregation induced by ionomycion, a calcium ionophore, in a concentration-dependent manner. These data lead us to suggest that flurazapam does not inhibit BPLC-ihduced platelet activation by inhibiting the action of BPLC or PI-PLC on platelet phospholipids or DAG production. However, the ability of flurazepam to inhibit ionomycin-induced platelet aggregation indicates that it may be blocking BPLC-induced platelet aggreagtion by interfering with the influx, of calcium ions into platelets. (Supported in part by the American Osteopathic Association, The Baker Award from Ohio University and the OUCOM).