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Maharani, Eva Ayu, and Dewi Astuti. "Comparison of Single Centrifugation, Double Centrifugation and Turn down-Turn up Techniques for Platelet-Rich Plasma Quality." Althea Medical Journal 9, no. 3 (2022): 180–84. http://dx.doi.org/10.15850/amj.v9n3.2628.
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Background: Platelet-rich plasma (PRP) is a new concept used in medical world, especially for wound healing. The main process that affects the PRP quality is the centrifugation process. This study aimed to assess the PRP separation process and determine the best technique of various centrifugation process.Methods: This experimental study used acid citrate dextrose (ACD) blood taken from 11 healthy respondents and compared three-techniques including the single centrifugation (SC), the double centrifugation (DC), and the double centrifugation turn down - turn up (DC-TDTU) techniques. The quality of PRP was measured based on blood cells count (platelet, leukocyte, erythrocyte count, and Ht value) at each stage of centrifugation. The examination was carried out in 2021 at the Hematology Laboratory, Poltekkes Jakarta 3.Results: The mean values of platelets, leukocytes, and Ht were increased in PRP compared to plasma supernatant both using the DC and DC-TDTU techniques, wherase the SC technique decreased in plasma compared with whole blood. When the procedures using DC and DC-TDTU are carried out properly, platelets would be concentrated in the second centrifugation. However, some erythrocyte and leukocyte contamination occurred by DC-TDTU technique compared to the DC technique.Conclusion: The double centrifugation technique is the best Platelet-rich plasma separation technique compared to the DC-TDTU and SC techniques.
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Walker, Randall C. "Lysis-Centrifugation Blood Culture Technique." Archives of Internal Medicine 146, no. 12 (1986): 2341. http://dx.doi.org/10.1001/archinte.1986.00360240055010.
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Novia, Diana, and Binarwan Halim. "#302 : Shorter Centrifugation Time Leads to Better Sperm Quality in Swim-Up Processing Technique." Fertility & Reproduction 05, no. 04 (2023): 700. http://dx.doi.org/10.1142/s2661318223744120.
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Background and Aims: Centrifugation is one of the many factors that cause sperm DNA damage in IVF semen preparation. This can occur due to the formation of reactive oxygen species (ROS) that are uncontrollable, so that the quality of sperm DNA can be damaged. This study aims to compare sperm quality results with swim-up technique under centrifugation times of 5 and 10 minutes. Method: This study involved 50 patients at the Halim Fertility Center clinic from June 2020 to October 2020. The samples obtained were processed using the swim-up method. Samples were divided into 3 groups, namely control, 5 and 10 minutes of centrifugation. Sperm quality recorded was concentration, total motility, progressive motility and DNA fragmentation index (DFI). Results: The sperm concentration after 5- and 10-min centrifugation before swim-up (27.78-39.79 and 35.36–51.09, respectively; p [Formula: see text] 0.05) was significantly higher compared to control (24.85–32.33). The total motility before and after 5- and 10-min centrifugation were 43.78–51.08, 97.66–98.20, and 97.86–98.20, respectively. The progressive motility after 5- and 10-min centrifugation (0–41 and 0–54, respectively) was significantly higher than control (0–24; p < 0.05). The DFI was significantly better after 5 min centrifugation (3.82–6.98) compared to control and after 10 min centrifugation (13.48–19.04 and 1–25, respectively; p < 0.05). Conclusion: Shorter centrifugation times indicate lower progressive motility than long centrifugation times, but considering the lower DFI level, shorter centrifugation times must be used in sperm preparation for IVF to produce better sperm quality.
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Fallatah, Majed Hashem, Aaied Falah Al Otaibi, Randa Rajallah Aljohani, Waad Jamal Ghabban, and Alaa Ali Alshehri. "Evaluation of Centrifugation Technique and the Effect of Centrifugation Condition on the Laboratory Samples." JOURNAL OF HEALTHCARE SCIENCES 04, no. 12 (2024): 1003–9. https://doi.org/10.52533/johs.2024.41248.
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Centrifugation is a critical laboratory technique used to separate components within a mixture based on density differences. The efficiency and reliability of this process depend on the precise control of variables such as speed, time, temperature, and rotor design. Improper centrifugation settings can compromise sample integrity, leading to analytical inaccuracies. High-speed centrifugation, while effective for rapid separation, often imposes mechanical stress on samples, resulting in hemolysis or cellular damage. Time duration is equally significant, as insufficient centrifugation can cause incomplete separation, while prolonged exposure may induce thermal stress and biochemical degradation. Temperature control plays a pivotal role, particularly for temperature-sensitive biomolecules like enzymes, nucleic acids, and proteins. Unregulated temperatures during high-speed centrifugation can denature proteins and degrade nucleic acids, affecting their utility in downstream applications such as diagnostics and molecular biology. Automated centrifuges equipped with programmable cooling systems have proven effective in mitigating these risks. Centrifugation protocols require customization based on sample type. Blood, urine, and cellular samples exhibit distinct sensitivities to centrifugal force and duration, necessitating tailored approaches. Specialized techniques, such as density-gradient centrifugation, enhance separation precision for applications like exosome isolation. Recent innovations in centrifuge technology, including programmable speed ramps and advanced rotor designs, have significantly improved the reproducibility and reliability of centrifugation processes. Standardization of centrifugation protocols is essential to ensure consistency in laboratory results. Advances in centrifuge design and optimization strategies have enabled better preservation of sample integrity across diverse applications. These developments highlight the need for continuous refinement of protocols to accommodate emerging diagnostic and research requirements, ensuring high-quality outcomes in both clinical and experimental settings.
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Taglioretti, V., N. Sardella, and M. Fugassa. "Effectiveness of coproscopic concentration techniques." Helminthologia 51, no. 3 (2014): 210–14. http://dx.doi.org/10.2478/s11687-014-0231-x.
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AbstractThe aim of the present study was to compare the effectiveness of the concentration techniques of flotation-centrifugation with zinc chloride (FZn) (δ = 1.45) with the spontaneous sedimentation (SSed) and the sucrose flotation-centrifugation (FSuc) (δ = 1.2) to recuperate gastrointestinal parasites from camelid fecal samples. The technique with more positive results for the detection of Nematodirus sp., Trichuris sp., strongyle-type eggs and Eimeria macusaniensis oocysts was the FZn. For Trichuris sp. and Eimeria macusaniensis, the higher coverglass counts were detected by FZn procedure. No significant differences were registered among centrifugation flotation techniques for Nematodirus spp. Coverglass count for strongyle-type eggs was significantly higher for FSuc than FZn (p = 0.0005) or SSed (p = 0.0005), being also significantly higher for FZn than for SSed (p = 0.008). FZn is a sensitive technique that allows the recovery of parasite elements with high density and it exerts low osmotic pressure avoiding parasite deformation.
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Lebl, Michal. "Centrifugation Based Automated Synthesis Technologies." JALA: Journal of the Association for Laboratory Automation 8, no. 3 (2003): 30–35. http://dx.doi.org/10.1016/s1535-5535-04-00267-9.
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Centrifugation is a powerful method for solid-liquid separation. It can be applied in numerous ways to simplify solid phase synthetic procedures. At the same time, centrifugation is the only totally parallel technique which can be scaled up for processing volume or number of simultaneously run reactions, without the limitation of overpressure or vacuum-driven filtration-based systems. We have developed synthesizers based on the power of centrifugation — peptide and small organic molecule synthesizers utilizing cotton as the synthetic substrate and inclusion volume chemistry, synthesizers for automation of “tea bag” synthesis, and synthesizers based on “tilted plate centrifugation”. The last technique was employed in an oligonucleotide production facility with the capacity of more than 10 million compounds per year.
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Matas, C., J. Gadea, and G. Decuadro-Hansen. "89 EVALUATION OF A CUSHIONED CENTRIFUGATION TECHNIQUE FOR PROCESSING BOAR SEMEN FOR FREEZING." Reproduction, Fertility and Development 17, no. 2 (2005): 195. http://dx.doi.org/10.1071/rdv17n2ab89.
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Boar semen freezing procedures include the use of centrifugation to concentrate sperm and remove seminal plasma prior to dilution in freezing extender. The centrifugation techniques employed have necessarily been a compromise between the need to recover as many spermatozoa as possible after centrifugation and the damage caused by pelleting the sperm. The use of an inert, dense, and isotonic solution as a cushion in the bottom of the tube leads to the use of higher-speed centrifugation to ensure maximum sperm recovery. However, it is necessary to know the viability and functionality of the samples after the thawing process. The aim of this work was to evaluate the effect of cushion-technique centrifugation on the in vitro sperm viability and the penetrating capacity after thawing. Sperm-rich fractions from five fertile boars were diluted and cooled to 15°C before centrifugation. Two centrifugation regimes were used: 800g for 10 min called the “standard method” (SM) (Westendorf P etal. 1975 Dtsch. Tierzartl Wochenschr. 82, 261–267) and 1000g for 20 min on an iodixanol isotonic solution 60% w/v gradient (Sigma Chemical Co., St. Louis, MO, USA) called the “cushion method” (CM). Spermatozoa were diluted in lactose/egg-yolk extender, cooled to 5°C over 2 h and then frozen with glycerol and Equex by classic methodology (Westendorf P et al. 1975 Dtsch. Tierzartl Wochenschr. 82, 261–267). Frozen sperm samples were thawed in a circulating water bath at 38°C for 30 s. To detect increases in plasma membrane lipid packing disorder and viability, frozen-thawed samples of sperm were stained with merocyanine 540 (M540) and Yo-Pro 1 (Harrison et al. 1996 Mol. Rep. Dev. 45, 378–391) and evaluated by flow cytometry. In vitro penetration ability was assessed using the homologous in vitro penetration (hIVP) test with immature oocytes (Gadea and Matas 2000 Theriogenology 54, 1343–1357). ANOVA analysis revealed that centrifugation by CM showed higher values of intact viable spermatozoa than SM centrifugation (60.21 v. 54.68%, P < 0.05). The in vitro penetration assay showed no differences in penetration rate or mean number of sperm penetrated per oocyte. However, significant boar and interaction effects were found (P < 0.01). These results indicated that different effects of the treatment were found for every boar. In conclusion, the cushioned centrifugation method gives a simple means of processing porcine semen for freezing more efficiently without loss of fertilizing capacity. This work was supported by AGL-2003-03144.
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Singhal, Ankita, Sheetal Goenka, and Dimple Kasana. "Revolutionizing Sterile Sample Culturing: Cost-Effective Centrifugation Techniques for Research in Resource- Constrained Settings." European Journal of Medical and Health Research 1, no. 1 (2023): 30–33. http://dx.doi.org/10.59324/ejmhr.2023.1(1).05.
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Introduction: The yield (culture positive rate) of sterile body fluids in patients was found to be less than 50%. It has been demonstrated that centrifuging body fluid before culturing increases yield. Using concentrated bacterial samples to enhance culture growth is a more effective alternative. We sought to determine whether sterile fluid culture yield was increased by centrifugation. Methods: Patients whose body fluids were received in sufficient quantity in the microbiology lab were enrolled. Sterile body fluids culture was carried out after centrifugation and by routine conventional inoculation method which was taken as a reference method. Results: 250 samples were included in the study over six months. Of the 250 samples, 15 came positive by the conventional method and 37 came positive by centrifugation technique. Comparisons were made between the turnaround times for the two methods. However, the centrifugation approach immediately produced positive Gram stain results for 19 samples (p = 0.03) while the reference method only produced three positive results. When compared to using the reference technique, the centrifugation method achieved bacterial identification and sensitivity on average more quickly (p 0.00001). Conclusion: The centrifugation technique was successful in producing the desired outcomes and may be used in the future with such precious samples. The centrifugation technique may shorten the turnaround time for culture reports, improving the management of infectious disorders.
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Singhal, Ankita, Sheetal Goenka, and Dimple Kasana. "Revolutionizing Sterile Sample Culturing: Cost-Effective Centrifugation Techniques for Research in Resource- Constrained Settings." European Journal of Medical and Health Research 1, no. 1 (2023): 30–33. https://doi.org/10.59324/ejmhr.2023.1(1).05.
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Introduction: The yield (culture positive rate) of sterile body fluids in patients was found to be less than 50%. It has been demonstrated that centrifuging body fluid before culturing increases yield. Using concentrated bacterial samples to enhance culture growth is a more effective alternative. We sought to determine whether sterile fluid culture yield was increased by centrifugation. Methods: Patients whose body fluids were received in sufficient quantity in the microbiology lab were enrolled. Sterile body fluids culture was carried out after centrifugation and by routine conventional inoculation method which was taken as a reference method. Results: 250 samples were included in the study over six months. Of the 250 samples, 15 came positive by the conventional method and 37 came positive by centrifugation technique. Comparisons were made between the turnaround times for the two methods. However, the centrifugation approach immediately produced positive Gram stain results for 19 samples (p = 0.03) while the reference method only produced three positive results. When compared to using the reference technique, the centrifugation method achieved bacterial identification and sensitivity on average more quickly (p 0.00001). Conclusion: The centrifugation technique was successful in producing the desired outcomes and may be used in the future with such precious samples. The centrifugation technique may shorten the turnaround time for culture reports, improving the management of infectious disorders.
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Santana, Tamara, Jorge Moreno, Guillermo Petzold, Roberto Santana, and Guido Sáez-Trautmann. "Evaluation of the Temperature and Time in Centrifugation-Assisted Freeze Concentration." Applied Sciences 10, no. 24 (2020): 9130. http://dx.doi.org/10.3390/app10249130.
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Centrifugation is a technique applied to assist in the freeze concentration of fruit juices and solutions. The aim of this work was to study the influence of the time–temperature parameters on the centrifugation process as a technique applied to assist in the first cycle of the freeze concentration of blueberry juice. A completely randomized 4 × 3 factorial design was performed using temperature and time as the factors, and the response variables included the percentage of concentrate, efficiency and solutes recovered. The results were evaluated using multiple linear regression, random forest regression, and Gaussian processes. The solid content in the concentrate doubled compared to the initial sample (18 °Brix) and approached 60% in the first cycle of blueberry juice freeze concentration. The combination of factors affected the percentage of the concentrate and solutes recovered, and the optimum of concentration was obtained at 15 °C with a centrifugation time of 20 min. Gaussian processes are suggested as suitable machine learning techniques for modelling the quantitative effect of the relevant factors in the centrifugation process.
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Yin, X., L. R. Zeph, and G. Stotzky. "A simple method for enumerating bacteriophages in soil." Canadian Journal of Microbiology 43, no. 5 (1997): 461–66. http://dx.doi.org/10.1139/m97-065.
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A plaque technique that uses antibiotic-resistant bacteria growing on antibiotic-containing agar for the assay lawn resulted in significantly better recovery of bacteriophages P1 of Escherichia coli and F116 of Pseudomonas aeruginosa from nonsterile soil than standard membrane filtration or centrifugation techniques. Adsorption of the phages on soil particles appeared to be involved in their recovery and survival in soil.Key words: bacteriophages, soil, antibiotic-resistant bacteria, enumeration, filtration, centrifugation.
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Gadea, J., S. Martínez-Miró, G. Decuadro-Hansen, and C. Matás. "92 EVALUATION OF BOAR SPERM FUNCTIONALITY AFTER A CUSHIONED CENTRIFUGATION TECHNIQUE." Reproduction, Fertility and Development 18, no. 2 (2006): 154. http://dx.doi.org/10.1071/rdv18n2ab92.
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Separation of sperm from seminal plasma is required in most semen freezing procedures. Semen is typically subjected to centrifugation to concentrate sperm into a pellet and allow removal of the seminal plasma prior to dilution in freezing extender. Centrifugation is a relatively effective method to recover sperm, however, the process also causes considerable sperm damage. The use of a dense, inert, and isotonic solution as a cushion in the bottom of the centrifuge tube allows a greater centrifugation speed to be applied and results in greater sperm recovery. The aim of the present work was to evaluate the effects of this cushioned centrifugation technique on in vitro sperm viability and functionality. Sperm-rich fractions from 16 fertile boars were diluted and cooled to 15�C; then subsamples were centrifuged by one of two different techniques. A standard method (SM), 800 g for 10 min in 50-mL tubes (Westendorf et al. 1975 Dtsch. Tier�rztl. Wschr. 82, 261-267) and a cushioned method (CM), 1000 g for 20 min using 45 mL of diluted semen on 5 mL of an isotonic iodixanol solution (60% w/v gradient) were performed. Sperm samples were stained with merocyanine 540 (M540) and Yo-Pro 1 (Harrison et al. 1996 Mol. Rep. Dev. 45, 378-391) to detect changes in lipid packing disorder of the plasma membrane. Another set of sperm samples was incubated in the presence of (0.7 �M) 22,72-dichlorodihydrofluorescein diacetate (Gadea et al. 2005 J. Androl. 26, 396-404) to estimate production of reactive oxygen species (ROS). A final set of sperm samples was stained with peanut aggultinin-fluorscein isothiocyanate (PNA-FITC) and propidium iodide to evaluate the acrosome reaction. All of these parameters were evaluated by flow cytometry before and after centrifugation. ANOVA analysis revealed that centrifugation altered lipid packing disorder and viability. Raw semen (RS) had a larger number of viable low lipid disorder sperm than centrifuged semen (RS = 86.9a vs. SM = 81.64b vs. CM = 80.6b, P < 0.01) and a decreased number of dead sperm cells (RS = 9.5a vs. SM = 15.0b vs. CM = 16.3b, P < 0.01). However, the cushioned and standard centrifugation methods yielded similar results for all the parameters measured. No significant differences were found for generation of ROS or in the number of sperm exhibiting the acrosome reaction. In conclusion, compared to the standard centrifugation method, this simple cushioned modification is a more efficient means of processing boar semen for freezing because significantly less sample losses are detected; also, it provides similar levels of sperm viability and functionality, and consequently a higher number of doses per ejaculation can be produced.
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Traynor, L., R. Sutton, J. Riley, FA Crawford, and RM Sade. "Comparing Ultrafiltration and Centrifugation During and After Pediatric Cardiopulmonary Bypass." Journal of ExtraCorporeal Technology 23, no. 3 (1991): 140–51. http://dx.doi.org/10.1051/ject/1991233140.
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Blood processing techniques related to pediatric cases have previously been generalized from adult experiences. Twenty-two pediatric patients (<25 kilograms) undergoing cardiopulmonary bypass (CPB) for various congenital defects were prospectively randomized into an ultrafiltration or centrifugation group. Sixty-one variables were compared. The blood infused from the ultrafiltration technique contained significantly more heparin (p=0.0001) and more plasma-free hemoglobin (PFH) (p=0.0001) levels than the centrifugation blood. Centrifugation patients had a significantly higher hematocrit (p=0.0066) than the ultrafiltration group twenty minutes postoperatively. The ultrafiltration patients (mean=431.82cc±116.8) received less total packed red blood cell volume before and during bypass than the centrifugation group (mean=534.091cc±113.07). In the centrifugation group, wash volumes showed positive correlation to postoperative blood sodium levels (r= +0.4006, p< 0.05). No significant difference was found between postoperative and preoperative sodium levels (p> 0.05). PFH levels for both groups showed a significant positive correlation to postoperative creatinine levels (r= +.4029, p< 0.05) suggesting decreased postoperative renal function, but a significant negative correlation to post-bypass hematocrit (r= -.4548, p< 0.05). Post-bypass heparin levels in the circuit showed a significant positive correlation to heparin levels in the reinfusion blood for the ultrafiltration group (r= +.8025, p<0.05). Post-bypass PFH level in the circuit showed a significant positive correlation to PFH levels in the reinfusion blood for both groups (r= +.5339, p<0.05). No significant difference existed between the ultrafiltration and centrifugation groups for postoperative prothrombin and partial thromboplastin times. For pediatric cases, the centrifugation technique was found to be superior for post-bypass blood processing based on a higher postoperative patient hematocrit and the presence of less heparin and less PFH in the reinfused blood. The ultrafiltration technique was found to be superior for intraoperative blood processing due to a lower total packed red cell volume addition before and during bypass.
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Karina, Karina, Johannes A. Biben, Krista Ekaputri, et al. "Revisiting Fat Graft Harvesting and Processing Technique to Optimize Its Regenerative Potential." Plastic and Reconstructive Surgery - Global Open 13, no. 1 (2025): e6420. https://doi.org/10.1097/gox.0000000000006420.
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Background: The use of fat grafting has expanded to include cell and tissue regeneration, necessitating investigations to ensure the viability of stromal and adipose-derived mesenchymal stem cells (ASCs) within the transferred fat parcels. This study explored the impact of harvesting technique and centrifugation on the viability of stromal cells and ASCs in lipoaspirate. Methods: Fat was harvested from patients undergoing fat grafting using 2 types of liposuction cannula: (A) a 3-mm blunt tip cannula with 3 smooth holes and (B) a 2.4-mm, sharp point port, multihole blunt tip cannula. Fat from cannula B underwent different processing methods: no centrifugation, 300g, 600g, and 900g centrifugation. Stromal cells were isolated, quantified, and evaluated for viability. ASCs were cultured from these samples to confirm survival. Results: Lipoaspirates from 21 patients were analyzed. The mean stromal cell counts were 0.937 × 109 ± 0.346 × 109/mL for cannula A and 0.734 × 109 ± 0.266 × 109/mL for cannula B (P = 0.684), with viabilities of 98.79% and 98.22% (P = 0.631), respectively. ASCs isolated and after 2-passage culture were also higher for cannula A. Stromal cell quantification and viability were lowest in the noncentrifuged group (P < 0.05) and highest in the 600g centrifugation group. Conclusions: Fat harvesting using cannulas A and B showed no significant difference in stromal cell yield or viability. Handheld syringe liposuction preserved stromal vascular fraction cell and ASC viability. Centrifugation at different speeds did not significantly affect stromal cell viability.
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Rey, Marcel, Maximilian J. Uttinger, Wolfgang Peukert, Johannes Walter, and Nicolas Vogel. "Probing particle heteroaggregation using analytical centrifugation." Soft Matter 16, no. 14 (2020): 3407–15. http://dx.doi.org/10.1039/d0sm00026d.
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We study the aggregation of silica particles and poly(N-isopropylacrylamide) microgels by analytical centrifugation. We demonstrate that the technique can yield quantitative information on the formation of defined clusters and large aggregates.
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Liu, Yong De, Hai Lu Wu, Jie Zhang, Dong Jin Wan, and Ji Hong Zhao. "Study of Porcine Blood Decoloration Technique." Advanced Materials Research 518-523 (May 2012): 3980–83. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.3980.
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Livestock blood is a slaughtering by-product that has potential for animal protein sources, human consumption is limited due to its brown color causing dark hues to food and feed products. The aim of this work is to extract white and palatable protein from red cells of porcine blood. Red cells are hydrolyzed with papain and acidized with Hydrochloric acid, freed heme group is flocculated with Sodium Carboxy Methyl Cellulose (CMC) and separated by centrifugation, supernatant is the decoloring protein solution. The enzyme hydrolysis conditions and flocculation conditions are optimized. The optimal enzyme hydrolysis parameters are substrate concentration 6%, papain dosage 6000u/g, time 8h and pH 7.0. The optimal enzyme flocculation parameters are CMC dosage 0.8g/g, pH 2.7 and time 10min. Decoloring protein powder obtained by isoelectric precipitation, centrifugation and vacuum freeze-drying is 95% protein, only 1% ash, light-colored and almost tasteless.
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Katzap, Roberta M., Vany Elisa Pagnussatti, Ana Elizabeth Figueiredo, et al. "Time to Positivity of Bacteria Cultures in Peritoneal Dialysis Fluid: Evaluation of Different Laboratory Techniques." Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 37, no. 3 (2017): 342–44. http://dx.doi.org/10.3747/pdi.2016.00174.
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Patients with chronic kidney disease on peritoneal dialysis (PD) are susceptible to infections, with peritonitis being the primary cause of dropout. Peritoneal fluid culture is one of the essential elements for proper diagnosis and peritonitis treatment. The aim of this study was to compare the time required to obtain a positive culture using different laboratory methods. An in vitro cross-sectional study was conducted comparing different techniques for preparation and culture of bacteria in peritoneal fluid. The research was carried out with 21 sterile dialysis bags and 21 PD bags containing peritoneal fluid drained from patients without peritonitis. Fluids from the 42 PD bags were contaminated by injecting a coagulase-negative Staphylococcus suspension and then prepared for culture using 4 distinct techniques: A - direct culture; B - post-centrifugation culture; C - direct culture after 4 h sedimentation; and D - culture after 4 h sedimentation and centrifugation. This was followed by seeding. In the 21 contaminated sterile bags, mean times to obtain a positive culture with techniques D (19.6 h ± 2.6) and C (19.1 h ± 2.3) were longer than with technique A (15.8 h ± 3.0; p < 0.01), but not statistically different from group B (19.0 h ± 3.2). The same occurred in the 21 bags drained from patients, with mean times for techniques D (14.0 h ± 1.9) and C (14.5 h ± 1.7) being longer than technique A (12.22 h ± 1.94; p < 0.05) but not statistically different from technique B (13.2 h ± 1.3). The sedimentation and centrifugation steps seem to be unnecessary and may delay antibiotic sensitivity test results by approximately 8 hours.
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Denardin, Norimar D'Ávila, and Vanessa Andréia Agostini. "Detection and quantification of Xanthomonas axonopodis pv. phaseoli and its variant fuscans in common bean seeds." Journal of Seed Science 35, no. 4 (2013): 428–34. http://dx.doi.org/10.1590/s2317-15372013000400003.
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The common bacterial blight of common beans (CBCF), a disease caused by Xanthomonas axonopodis pv. phaseoli (Xap) and Xanthomonas axonopodis pv. phaseoli var. fuscans (Xapf), significantly reduces grain yield and seed quality. Because this bacterium is mainly disseminated through infected seeds, efficient detection of Xap and Xapf is important to assure the productivity and quality of the crop. In this study, various techniques that included different extraction techniques (two different incubation times, with and without centrifugation) and five culture media (Kado 523, GYCA, MXP, NSA, and PTSA) were tested for the detection of the seed-borne inoculum, using three different seed samples. Overnight incubation of the seeds, followed by centrifugation and incubation in Kado 523 resulted in higher extraction of Xap and Xapf. The best extraction technique was overnight incubation followed by centrifugation, and the best medium was PTSA. Among the tested culture media, PTSA provided better identification and counting of the bacterial colonies, thus allowing the quantification of the seed infection levels.
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Massing, Ulrich, Sanja Cicko, and Vittorio Ziroli. "Dual asymmetric centrifugation (DAC)—A new technique for liposome preparation." Journal of Controlled Release 125, no. 1 (2008): 16–24. http://dx.doi.org/10.1016/j.jconrel.2007.09.010.
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Nelissen, Xavier, Séverine Licciardi, Christophe Nizet, Emmanuel Delay, and Régis Roche. "Comparative Analysis of a New Automatic System and Four Existing Techniques for Autologous Fat Grafting." Plastic and Reconstructive Surgery - Global Open 11, no. 10 (2023): e5349. http://dx.doi.org/10.1097/gox.0000000000005349.
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Background: Autologous fat grafting is increasingly used worldwide and is a very attractive technique in many ways. However, treatment duration and postinjection tissue resorption remain problematic elements, which are largely related to the preparation method used. Moreover, few scientific studies objectively compare different fat preparation methods. This study analyzes the efficiency and quality of lipoaspirates prepared with a new filtration/centrifugation system (Adipure) in comparison with several existing techniques. Methods: Patient lipoaspirates were processed by five different techniques: decantation, centrifugation, Macrofill, Puregraft, and Adipure. Adipose tissue was evaluated in vitro for tissue resorption and oil formation, as well as in vivo after subcutaneous injections in immunodeficient mice. Adipose grafts were collected after 1 month, weighed, and analyzed by histology with a detailed scoring method. Results: Decanting gives inferior results to all other techniques, in terms of amount of tissue and oil in vitro, or graft weight and histological analysis in vivo. Methods using classical Coleman centrifugation (1200g), or a modified one (400g) associated with washes (Macrofill) produce very similar results, both in vitro and in vivo. Techniques using filtration systems (Puregraft and Adipure) produce less oil overall and have a higher grafting efficiency. The best results regarding grafting efficiency and oil quantity are found with the Adipure device. Conclusions: A combination of filtration and very low-speed centrifugation potentiates the advantages of these techniques, in terms of graft efficiency. The adipose tissue purification being done in a few minutes, in an automatic way, undoubtedly provides a strong advantage for the use of this new system.
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Chandler, Ekta, Naveen Kakkar, and Rupinder Kaur. "Comparison of Rapid Centrifugation Technique with Conventional Centrifugation for Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT) Testing." Indian Journal of Hematology and Blood Transfusion 35, no. 1 (2018): 161–66. http://dx.doi.org/10.1007/s12288-018-0983-4.
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Gebre-Selassie, Solomon. "Evaluation of the Concentration Sputum Smear Technique for the Laboratory Diagnosis of Pulmonary Tuberculosis." Tropical Doctor 33, no. 3 (2003): 160–62. http://dx.doi.org/10.1177/004947550303300313.
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The microbiological diagnosis of pulmonary tuberculosis (PTB) plays a key role in routine and Tuberculosis (TB) Control Programmes in developing countries. Concentration of acid-fast bacilli (AFB) in clinical specimens is an important step in the laboratory diagnosis of mycobacterial diseases. Microscopy of smears of sputum by direct and after mechanical sedimentation and centrifugation methods followed by treatment with 5% sodium hypochlorite (NaOCl) solution for concentration of the organisms were compared and evaluated. The rate of recovery of AFB from sputum was 8.5%, 25.5% and 38.0% for direct smear microscopy, concentration by sedimentation of NaOCl-treated sputa followed by Ziehl-Neelsen staining and concentration by centrifugation after use of NaOCl respectively. Both the concentration methods by the use of NaOCl solution increased the yield of the AFB by more than threefold compared with the direct microscopy of sputum ( P<0.05). The concentration methods by sedimentation, and centrifugation by the treatment of NaOCl, increased the sensitivity to 75% and 77.9%, respectively, and the specificity to 100% for both techniques. In conclusion, the use of NaOCl in the concentration of AFB in sputum is recommended for use in routine laboratory diagnosis of PTB in developing countries.
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Haraguchi, Yuji, Akiyuki Hasegawa, Katsuhisa Matsuura, et al. "Three-Dimensional Human Cardiac Tissue Engineered by Centrifugation of Stacked Cell Sheets and Cross-Sectional Observation of Its Synchronous Beatings by Optical Coherence Tomography." BioMed Research International 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/5341702.
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Three-dimensional (3D) tissues are engineered by stacking cell sheets, and these tissues have been applied in clinical regenerative therapies. The optimal fabrication technique of 3D human tissues and the real-time observation system for these tissues are important in tissue engineering, regenerative medicine, cardiac physiology, and the safety testing of candidate chemicals. In this study, for aiming the clinical application, 3D human cardiac tissues were rapidly fabricated by human induced pluripotent stem (iPS) cell-derived cardiac cell sheets with centrifugation, and the structures and beatings in the cardiac tissues were observed cross-sectionally and noninvasively by two optical coherence tomography (OCT) systems. The fabrication time was reduced to approximately one-quarter by centrifugation. The cross-sectional observation showed that multilayered cardiac cell sheets adhered tightly just after centrifugation. Additionally, the cross-sectional transmissions of beatings within multilayered human cardiac tissues were clearly detected by OCT. The observation showed the synchronous beatings of the thicker 3D human cardiac tissues, which were fabricated rapidly by cell sheet technology and centrifugation. The rapid tissue-fabrication technique and OCT technology will show a powerful potential in cardiac tissue engineering, regenerative medicine, and drug discovery research.
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Bisiau, Christian, Paula Moffett, James Graham, and Patrick McCue. "Comparison of Nanoparticles and Single-Layer Centrifugation for Separation of Dead from Live Stallion Spermatozoa." Veterinary Sciences 11, no. 7 (2024): 307. http://dx.doi.org/10.3390/vetsci11070307.
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The goal of this study was to compare the efficacy of coated iron-core nanoparticles and single-layer centrifugation for separation of dead from live stallion spermatozoa. Our hypothesis was that nanoparticles would bind to dead sperm and allow for separation from live sperm using a magnet, resulting in a population of spermatozoa with a high percentage of total and progressive motility. Treatment Group 1 was an untreated control. Treatment Group 2 (nanoparticles, NP) utilized sperm incubated with nanoparticles followed by application of a magnet to remove dead sperm adhered to the coated nanoparticles. Treatment Group 3 (single-layer centrifugation, SLC) layered sperm above EquiPure™ followed by centrifugation. Semen samples were subsequently evaluated for sperm motility parameters, plasma membrane integrity, acrosome status, and morphology. The SLC technique yielded higher (p < 0.05) progressive motility (76 ± 9.2%) than the NP separation technique (59 ± 12.2%) or the untreated control (47.3 ± 5.1%). However, the total number of sperm recovered was higher (p < 0.05) in the NP technique (526.2 ± 96.6 × 106) than the SLC procedure (211.7 ± 70 × 106), yielding a higher total number of progressively motile sperm (317.6 ± 109 × 106) recovered using the NP technique than the SLC technique (157.8 ± 43.6 × 106). The percentage of live, acrosome intact sperm recovered was higher for SLC than NP. In summary, the SLC technique yielded a higher percentage of sperm motility, intact plasma membranes, and acrosome integrity, but yielded lower total sperm than with the nanoparticle separation technique.
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Webb, Gary W., and M. M. Dean. "Effect of Centrifugation Technique on Post-storage Characteristics of Stallion Spermatozoa." Journal of Equine Veterinary Science 29, no. 9 (2009): 675–80. http://dx.doi.org/10.1016/j.jevs.2009.07.016.
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Walker, R. C. "Lysis-centrifugation blood culture technique. Clinical impact in Staphylococcus aureus bacteremia." Archives of Internal Medicine 146, no. 12 (1986): 2341–43. http://dx.doi.org/10.1001/archinte.146.12.2341.
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Al-Timimi, Ihsan H. S. "Selection of male goat embryos in vitro by using swim-up of epididymal spermatozoa." Iraqi Journal of Veterinary Medicine 42, no. 1 (2018): 79–86. http://dx.doi.org/10.30539/iraqijvm.v42i1.35.
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The main objectives of this study is the separation of X from Y bearing epididymal spermatozoa of local buck by swim-up, and the use of this spermatozoa for in vitro fertilization to determine the percentage of produced male and female embryos. The sex of produced embryo was identified by polymerase chain reaction. Testis of the local buck were obtained from Al-Shu'alah abattoir and the epididymal spermatozoa were harvested from the cauda by and submitted to in vitro maturation prior to separation of X from Y bearing spermatozoa and prior to their use for in vitro fertilization. For the separation of epididymal spermatozoa, swim-up technique was used with centrifugation at 200×g or 300×g. The centrifugation at 200×g showed that 41.84±1.39 % of spermatozoa were detected in the supernatant while the precipitate contained 50.69±0.71 and the mean of the sperm lost was 7.65±0.93. After centrifugation, spermatozoa in the supernatant were used for in vitro fertilization of matured oocytes. The sex of in vitro produced goat embryos was determined by polymerase chain reaction using specific primers to detect of SRY gene. The percentage of total goat embryos obtained after in vitro fertilization by sperms selected using swim-up at centrifugation force of 200×g recorded 79.66 % male embryos while female embryos recorded only 20.33 %. At the end, the results showed the ability of selection male embryos in caprine by application of swim-up technique on epididymal spermatozoa with centrifugation at 200×g.
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Hu, Qin, Xiaojuan Gong, Lizhen Liu, and Martin M. F. Choi. "Characterization and Analytical Separation of Fluorescent Carbon Nanodots." Journal of Nanomaterials 2017 (2017): 1–23. http://dx.doi.org/10.1155/2017/1804178.
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Carbon nanodots (C-dots) are recently discovered fluorescent carbon nanoparticles with typical sizes of <10 nm. The C-dots have been reported to have excellent photophysical and chemical characteristics. In recent years, the advances in the development and improvement in C-dots synthesis, characterization, and applications are burgeoning. In this review, we introduce the most commonly used techniques for the characterization of C-dots. The characterization techniques for C-dots are briefly classified, described, and illustrated with applied examples. In addition, the analytical separation methods for C-dots (including electrophoresis, chromatography, density gradient centrifugation, differential centrifugation, solvent extraction, and dialysis) are included and discussed according to their analytical characteristics. The review concludes with an outlook towards the future developments in the characterization and the analytical separation of C-dots. The comprehensive overview of the characterization and the analytical separation techniques will safeguard people to use each technique more wisely.
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Yudiwati, Rina, MPBD Pramesti, Agustinus Agustinus, E. Pradana, and Bambang Purwanto. "IMPACT OF PREPARATION USING CONVENTIONAL AND MODIFIED DENSITY GRADIENT CENTRIFUGATION METHODS ON SPERM CONCENTRATION, MOTILITY AND NUMBER OF NORMAL MOTILE SPERM RECOVERY (NMSR)." Folia Medica Indonesiana 53, no. 3 (2017): 196. http://dx.doi.org/10.20473/fmi.v53i3.6447.
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Some preparation techniques, either conventional or advanced, have been provided. Advanced technique may overcome the limitations of conventional techniques. Recently, not all fertility clinics in Indonesia are able to provide advanced preparation techniques. Some techniques require expensive equipments and can only be used for intracytoplasmic sperm injection (ICSI). Some fertility clinics use a modified procedure, namely the combination of density gradient centrifugation with a swim-up method for the preparation of the sperm to be used in ART. This study aimed to determine whether the modified density gradient centrifugation, which is density gradient centrifugation followed by a swim-up, is able to yield better results than conventional density gradient centrifugation. This study was a laboratory experimental pre and pos-test control group design. Population was all adult men aged 21-40 years old and the sampling unit was the man donor’s semen which fulfilled inclusion criterias, collected during the periode of the study. Sample size was eight. Sperm analysis were done before and after preparation in conventional and modified group. Descriptive comparation analysis have been used. This study obtained NMSR 7.9+5.5 million/ejaculate and recovery rate (RR) 27.66+11.8 %. RR was lower compared to RR obtained conventional DGC method. RR might be lower because in modified DGC samples undergo two steps selection while conventional DGC only one step selection. But conventional DGC samples should be centrifuged twice, therefore sperms might experience more trauma. Lower RR sperm does not exclude the possibility to be used for ART, because still within the required number for all TRBs. In conclusion, modified DGC preparation method obtained lower NMSR and RR, nevertheless harvested sperms can still be used in all kind of ART.
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Büscher, Philippe, Dieudonné Mumba Ngoyi, Jacques Kaboré, et al. "Improved Models of Mini Anion Exchange Centrifugation Technique (mAECT) and Modified Single Centrifugation (MSC) for Sleeping Sickness Diagnosis and Staging." PLoS Neglected Tropical Diseases 3, no. 11 (2009): e471. http://dx.doi.org/10.1371/journal.pntd.0000471.
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Chetverikov, Sergiy, and Dmitro Atanasov. "ORIGINAL EFFECTIVE, SAFE TECHNIQUE OF OBTAINING PLATELET RICH PLASMA BY CENTRIFUGATION OF THE BLOOD PLASMA IN MODIFIED SYRINGE CONTAINERS." EUREKA: Health Sciences 1 (January 31, 2019): 3–9. http://dx.doi.org/10.21303/2504-5679.2019.00844.
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The aim: to develop, substantiate an effective and safe technology for producing PRP (platelet rich plasma). To quantify the substrate based on the recommended centrifugation protocols. Materials and methods: the effectiveness of the original harvesting protocol was evaluated by quantifying the number of platelets. The proposed technique is formed basing on the basic principles of double centrifugation of whole blood in test tubes with anticoagulant, separation with the release of a plasma layer with a high content of platelets. The centrifuging mode for quantifying the effectiveness of the substrate was selected according to recommendations based on a study confirming maximum efficiency (160g×10min + 250g×15min). For quantitative evaluation, blood was collected from 10 healthy volunteers (7 men, 3 women) with an average age of 26.0±2.6, and centrifuged in standard mode. Quantitative evaluation of platelets of whole blood and the obtained PRP substrate was carried out with a semi-automatic analyzer. Results: the proposed technique is based on the use as a container for centrifuging a syringe with a LuerLock design, which is hermetically sealed with a congruent plug, adapted by the external size of the centrifuge rotor bowl. Phase selection after centrifugation was performed by aspiration of the syringe contents after centrifugation is performed through a three-way valve. The substrate was obtained by repeated centrifugation of the contents, which allows obtaining a variable volume and platelet concentration in PRP. The amount of platelets (PLT) of whole blood is 227.0±57.0 thousand per ml. PLT PRP 945.0±279.0 thousand per ml. Conclusions: the proposed method of separation of whole blood with the release of the platelet rich plasma demonstrates high efficiency, which corresponds to the level of increasing the number of platelets in reducing the volume at the level of the best ready-made solutions. The equipment is economical and does not require highly specialized equipment and consumables. The proposed technique provides a wide choice to the performer in the received volume of the substrate.
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Sergiy, Chetverikov, and Atanasov Dmitro. "ORIGINAL EFFECTIVE, SAFE TECHNIQUE OF OBTAINING PLATELET RICH PLASMA BY CENTRIFUGATION OF THE BLOOD PLASMA IN MODIFIED SYRINGE CONTAINERS." EUREKA: Health Sciences, no. 2 (March 31, 2019): 3–9. https://doi.org/10.21303/2504-5679.2019.00844.
Full textAbstract:
<strong>The aim:</strong> to develop, substantiate an effective and safe technology for producing PRP (platelet rich plasma). To quantify the substrate based on the recommended centrifugation protocols. <strong>Materials and methods:</strong> the effectiveness of the original harvesting protocol was evaluated by quantifying the number of platelets. The proposed technique is formed basing on the basic principles of double centrifugation of whole blood in test tubes with anticoagulant, separation with the release of a plasma layer with a high content of platelets. The centrifuging mode for quantifying the effectiveness of the substrate was selected according to recommendations based on a study confirming maximum efficiency (160g×10min + 250g×15min). For quantitative evaluation, blood was collected from 10 healthy volunteers (7 men, 3 women) with an average age of 26.0±2.6, and centrifuged in standard mode. Quantitative evaluation of platelets of whole blood and the obtained PRP substrate was carried out with a semi-automatic analyzer. <strong>Results:</strong> the proposed technique is based on the use as a container for centrifuging a syringe with a LuerLock design, which is hermetically sealed with a congruent plug, adapted by the external size of the centrifuge rotor bowl. Phase selection after centrifugation was performed by aspiration of the syringe contents after centrifugation is performed through a three-way valve. The substrate was obtained by repeated centrifugation of the contents, which allows obtaining a variable volume and platelet concentration in PRP. The amount of platelets (PLT) of whole blood is 227.0±57.0 thousand per ml. PLT PRP 945.0±279.0 thousand per ml. <strong>Conclusions:</strong> the proposed method of separation of whole blood with the release of the platelet rich plasma demonstrates high efficiency, which corresponds to the level of increasing the number of platelets in reducing the volume at the level of the best ready-made solutions. The equipment is economical and does not require highly specialized equipment and consumables. The proposed technique provides a wide choice to the performer in the received volume of the substrate.
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Bonilla-Gutiérrez, Andres Felipe, Catherine Aragón-Urrego, and Omar Leonardo Aristizábal-Páez. "Protocolo para la obtención de un Concentrado Autólogo de Plaquetas en conejos: estudio piloto." Revista de la Facultad de Medicina Veterinaria y de Zootecnia 64, no. 1 (2017): 24–31. http://dx.doi.org/10.15446/rfmvz.v64n1.65813.
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One of the main difficulties presented in surgical practice, is the restoration of the integrity of the tissues that are affected by the pathology or the surgical technique performed for its resolution. Currently, techniques and treatments are developed focused to improve scarring processes tissue and promote tissue regeneration; one of them is Autologous Platelets Concentrate (APC). The aim of the present study was evaluate the blood collection and processing technique for obtaining APC in a lagomorph model. New Zealand male rabbits (n=10), with weights ranging from 3 to 3.8 kg, were used as experimental model. The blood sample of each animal was obtained by puncture of the jugular vein into tubes with sodium citrate and centrifuged at 120 g for 5 minutes. The levels oferythrocytes, leukocytes and platelets after the centrifugation process presented statistically significant differences (P < 0.05) compared to whole blood. The results of this study support the conclusion that the development of a APC for leporidae species is feasible, obtaining platelets without morphology alterations after a single centrifugation cycle.
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Sinha, K., U. Tendolkar, and M. Mathur. "Comparison of Conventional Broth Blood Culture Technique and Manual Lysis Centrifugation Technique for Detection of Fungemia." Indian Journal of Medical Microbiology 27, no. 1 (2009): 79–80. http://dx.doi.org/10.1016/s0255-0857(21)01766-7.
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Chetverikov, Sergiy, and Dmitro Atanasov. "EVALUATION OF CENTRIFUGING REGIMES FOR THE PURPOSE OF OPTIMIZING THE PLATELET RICH PLASMA HARVESTING PROTOCOL." EUREKA: Health Sciences 2 (March 31, 2019): 11–18. http://dx.doi.org/10.21303/2504-5679.2019.00881.
Full textAbstract:
Aim: Based on the classical principles, to determine the optimal conditions for centrifugation, PRP harvesing (platelet-rich plasma). To conduct a quantitative assessment of the substrate obtained under different conditions of centrifugation. Materials and methods. Based on the basic principles of obtaining platelet-rich plasma (PRP) by centrifuging in containers with an anticoagulant followed by phase separation to obtain the final substrate, the efficiency of the technique under the conditions of single and double centrifugation as well as under different conditions of acceleration and centrifugation was evaluated. Blood for follow-up was collected from 20 healthy volunteers (11 men, 9 women) average 25.3±4.1 in syringes of LuerLock design with ACD-A anticoagulant solution, and centrifuged. Centrifugation was carried out under controlled conditions using a centrifuge with rotating bowls of the rotor. Centrifugation was performed at an acceleration of 100-400g in time intervals up to 20 minutes. Activation of the substrate was performed with calcium chloride solution. Quantitative evaluation of platelets of whole blood and the final substrate of PRP was carried out with a semi-automatic analyzer. Results. The obtained results demonstrate the maximum level of harvesting efficiency when performing double centrifugation in the 150g×15 min+250g×10 min mode. Subject to this centrifugation protocol, it is possible to obtain a substrate that complies with the standardized requirements for PRP. The maximum level of an increase in the number of platelets in the substrate in comparison with whole blood is determined at the level of ×4.36 with concentration (volume reduction) x5 in comparison with the volume of whole blood. Conclusions. This study demonstrated the advantage of double centrifuging modes over single modes. According to the results of the study, it was possible to determine the conditions for an optimal double-centrifugation mode (acceleration and duration), which allows us to achieve the most efficient concentration of the substrate.
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GUTIERREZ, CARLOS, JUAN A. CORBERA, FRANCISCO DORESTE, and PHILIPPE BÜSCHER. "Use of the Miniature Anion Exchange Centrifugation Technique to IsolateTrypanosoma evansifrom Goats." Annals of the New York Academy of Sciences 1026, no. 1 (2004): 149–51. http://dx.doi.org/10.1196/annals.1307.020.
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Proudman, C., and G. Edwards. "Validation of a centrifugation/flotation technique for the diagnosis of equine cestodiasis." Veterinary Record 131, no. 4 (1992): 71–72. http://dx.doi.org/10.1136/vr.131.4.71.
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van der Vegt, S. G. L., A. M. Th Ruben, J. M. Werre, et al. "Counterflow centrifugation of red cell populations: a cell age related separation technique." British Journal of Haematology 61, no. 3 (1985): 393–403. http://dx.doi.org/10.1111/j.1365-2141.1985.tb02843.x.
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Meruane, Manuel, Alison Ford, Alejandro Swett, and Alvaro Ibarra. "The Impact of Liposuction Technique, Centrifugation and Freezing in Adipose Tissue Viability." Plastic and Reconstructive Surgery 134 (October 2014): 53–54. http://dx.doi.org/10.1097/01.prs.0000455393.68681.6a.
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Fournier, P. E., M. Drancourt, H. Lepidi, M. J. Gevaudan, and D. Raoult. "Isolation of Mycobacteria from Clinical Samples Using the Centrifugation-Shell Vial Technique." European Journal of Clinical Microbiology & Infectious Diseases 19, no. 1 (2000): 69–70. http://dx.doi.org/10.1007/s100960050015.
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Hopkins, D. W., S. J. Macnaughton, and A. G. O'Donnell. "A dispersion and differential centrifugation technique for representatively sampling microorganisms from soil." Soil Biology and Biochemistry 23, no. 3 (1991): 217–25. http://dx.doi.org/10.1016/0038-0717(91)90055-o.
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Buhler, Douglas D., and Bruce D. Maxwell. "Seed Separation and Enumeration from Soil Using K2Co3-Centrifugation and Image Analysis." Weed Science 41, no. 2 (1993): 298–302. http://dx.doi.org/10.1017/s0043174500076207.
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This research presents a modified floatation method to extract weed seed from soil samples and an automated imaging technique to enumerate seed following extraction. Rapid floatation of weed seed from soil in a K2CO3solution was facilitated by centrifugation. High recovery of seed from soil samples was accomplished in a relatively short time. Recovery of seed of giant foxtail and velvetleaf from a silt loam soil was near 100% and recovery of redroot pigweed was 86%. Germination of common lambsquarters, giant foxtail, and velvetleaf seed was reduced by exposure to K2CO3under certain conditions. However, these reductions do not appear to reduce the utility of this extraction technique. The automated image capture technique for counting seed showed similar limitations as with manual counting. Seed count accuracy generally decreased with increased number of seed and smaller seed sizes. In general, the image capture technique compared favorably with manual seed counting and has the potential to further improve seedbank assessment methods.
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Harnnoi, T., A. Wijit, N. Morakote, V. Pipitgool, and W. Maleewong. "Specific gravity of Opisthorchis viverrini eggs." Journal of Helminthology 72, no. 4 (1998): 359–61. http://dx.doi.org/10.1017/s0022149x00016746.
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AbstractThe specific gravity of the eggs of the liver fluke Opisthorchis viverrini was determined using a sucrose gradient centrifugation and found to range from 1.2713 to 1.3043. The peak egg count was located at the sucrose fraction with a specific gravity of 1.2814. An attempt to float eggs in saturated sodium nitrate solution, sp.gr. 1.4, failed. Examination of human stool specimens for O. viverrini eggs by simple flotation in saturated sodium nitrate solution and the formol-ether sedimentation technique revealed that the flotation technique was not as efficient as the sedimentation technique. It was suggested that the flotation techniques were inappropriate for the detection of O. viverrini eggs in faeces or contaminated soil.
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Sergiy, Chetverikov, and Atanasov Dmitro. "EVALUATION OF CENTRIFUGING REGIMES FOR THE PURPOSE OF OPTIMIZING THE PLATELET RICH PLASMA HARVESTING PROTOCOL." EUREKA: Health Sciences, no. 2 (March 31, 2019): 11–18. https://doi.org/10.21303/2504-5679.2019.00881.
Full textAbstract:
<strong>Aim: </strong>Based on the classical principles, to determine the optimal conditions for centrifugation, PRP harvesing (platelet-rich plasma). To conduct a quantitative assessment of the substrate obtained under different conditions of centrifugation. <strong>Materials and methods. </strong>Based on the basic principles of obtaining platelet-rich plasma (PRP) by centrifuging in containers with an anticoagulant followed by phase separation to obtain the final substrate, the efficiency of the technique under the conditions of single and double centrifugation as well as under different conditions of acceleration and centrifugation was evaluated. Blood for follow-up was collected from 20 healthy volunteers (11 men, 9 women) average 25.3±4.1 in syringes of LuerLock design with ACD-A anticoagulant solution, and centrifuged. Centrifugation was carried out under controlled conditions using a centrifuge with rotating bowls of the rotor. Centrifugation was performed at an acceleration of 100-400g in time intervals up to 20 minutes. Activation of the substrate was performed with calcium chloride solution. Quantitative evaluation of platelets of whole blood and the final substrate of PRP was carried out with a semi-automatic analyzer. <strong>Results. </strong>The obtained results demonstrate the maximum level of harvesting efficiency when performing double centrifugation in the 150g×15 min+250g×10 min mode. Subject to this centrifugation protocol, it is possible to obtain a substrate that complies with the standardized requirements for PRP. The maximum level of an increase in the number of platelets in the substrate in comparison with whole blood is determined at the level of ×4.36 with concentration (volume reduction) x5 in comparison with the volume of whole blood. <strong>Conclusions.</strong> This study demonstrated the advantage of double centrifuging modes over single modes. According to the results of the study, it was possible to determine the conditions for an optimal double-centrifugation mode (acceleration and duration), which allows us to achieve the most efficient concentration of the substrate.
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Aukland, K. "Distribution volumes and macromolecular mobility in rat tail tendon interstitium." American Journal of Physiology-Heart and Circulatory Physiology 260, no. 2 (1991): H409—H419. http://dx.doi.org/10.1152/ajpheart.1991.260.2.h409.
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This study explores a centrifugation technique for estimating interstitial fluid composition and macromolecular transport. Rat tail tendon supported by a nylon net was subjected to three consecutive 15-min centrifugations at 3,000, 6,000, and 14,000 revolutions per minute (rpm) or 3, 10, and 20 min at 6,000 rpm. Colloid osmotic pressure (COP) and concentrations of albumin, total protein, and hyaluronan in subsequent centrifugate fell as exponential functions of accumulated centrifuged volume, reaching 10-30% of initial level at an accumulated volume corresponding to 8% of tendon volume. Intercepts for zero centrifugation were 11 mmHg (COP), 22 mg/ml (albumin), and 39 mg/ml (total protein), probably reflecting concentrations in protein-accessible interstitial volume. Corresponding serum values were 19 mmHg, 34 mg/ml, and 63 mg/ml. Tendon distribution spaces were 0.62 (H2O), 0.57 (51Cr-labeled-EDTA), and 0.22 ml/g wet wt (albumin). The progressive fall in centrifugate concentrations probably reflects increasing resistance to macromolecular transport, with a sieving coefficient for albumin falling from 1 to 0.35, or increasing contribution of fluid from protein-excluded space. The effect was reversed by rehydration, which caused increased concentrations in centrifugate. Low hyaluronan concentrations in centrifugate (0.25 mg/ml) compared with that of whole tendon (0.4 mg/g wet wt) reflect either a large "bound" fraction in tissue or marked sieving of hyaluronan in normohydration.
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Lamaalla, Y., L. Idelkheir, Z. Alami, et al. "Autologous Fat Grafting for Facial Volume Restoration in Parry-Romberg Syndrome: A Retrospective Study of 7 Cases." Scholars Journal of Medical Case Reports 13, no. 05 (2025): 832–36. https://doi.org/10.36347/sjmcr.2025.v13i05.013.
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Background: Parry-Romberg syndrome (PRS) is a rare craniofacial disorder characterized by progressive hemifacial atrophy. While autologous fat grafting (AFG) has emerged as a promising treatment, long-term volumetric outcomes remain poorly characterized. Methods: This retrospective study analyzed 7 PRS patients (6F:1M; mean age 22±7.2 years) treated between 2021-2024. Fat was harvested via Coleman technique, processed by centrifugation (3000 rpm × 3 min), and injected in three anatomical layers Results: Mean volume retention was 62.3±8.7% at 12 months (p<0.01). Adipocyte viability correlated strongly with centrifugation force (83.2% at 3000 rpm vs 68.1% at 1200 rpm, p=0.003). FACE-Q scores improved from 32.1 to 78.4 (p<0.001). Conclusion: AFG provides durable restoration in PRS when performed with optimized processing parameters. This study establishes centrifugation at 3000 rpm as the gold standard for adipocyte preservation.
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Mailyan, Levon R., Sergey A. Stel’makh, Evgenii M. Shcherban’, et al. "Investigation of Integral and Differential Characteristics of Variatropic Structure Heavy Concretes by Ultrasonic Methods." Applied Sciences 11, no. 8 (2021): 3591. http://dx.doi.org/10.3390/app11083591.
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The article develops methods and methodology for experimental studies of centrifuged and vibro-centrifuged concrete products of annular cross-section. They assess the real variatropy of the structure and confirm the correctness of the accepted research. An original technique for experimental studies of the variatropy of the cross-sections of vibrated, centrifuged and vibro-centrifuged concretes is proposed to determine their integral (common) and differential (differing in layers) strength and strain characteristics and deformation diagrams. It has been proved that with vibro-centrifugation it becomes possible to obtain concretes with improved structure and higher characteristics compared with centrifugation and vibration techniques. Experimental studies of the differential characteristics of centrifuged and vibro-centrifuged concretes under compression and tension revealed that the outer layer of concrete had the best characteristics after centrifugation and vibro-centrifugation, and the inner layer had the worst ones. The three-layer model of the variatropic structure for centrifuged and vibro-centrifuged concrete has been experimentally confirmed. The concrete of the outer layers had the highest strength and modulus of elasticity and the least deformability; the concrete of the inner layers had the lowest strength and modulus of elasticity and the highest deformability; and the concrete of the middle layers had average characteristics. The deformation diagrams of centrifuged and vibro-centrifuged concretes were also differentiated by layers, confirming the variatropy of the structure of such concretes. The deformation diagrams for the outer concrete layer demonstrated the highest strength; the diagrams for the inner concrete layer showed the lowest strength; and the diagrams for the middle concrete layer corresponded to mean characteristics.
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Azcue, Jose M., and Fernando Rosa. "Effects of Sampling Technique on the Determination of Major and Trace Elements on Sediment Pore Water." Water Quality Research Journal 31, no. 4 (1996): 709–24. http://dx.doi.org/10.2166/wqrj.1996.038.
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Abstract Pore water samples obtained by squeezing, centrifuging followed by filtration, and in situ dialysis were compared. The effects of the three methods on the measured concentrations of eight elements (Ca, Fe, K, Mg, Mn, Na, Si and Sr) were studied. Iron and Mn proved to be extremely sensitive to oxygen exposure. Immediate centrifugation followed by filtration under nitrogen yield very similar results for almost all the elements as the in situ dialysis technique. The squeezing technique was the most susceptible to handling variables such as pressure-, oxygen- and temperature-related changes. Whenever possible, we recommend the use of in situ techniques that minimize the sampling artifacts. However, the choice of the technique for sampling sediment pore water should be dictated by the objectives of the study.
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Koehler, Jonas K., Stefanie Schmager, Valentin Bender, Denise Steiner, and Ulrich Massing. "Preparation of Nanosized Pharmaceutical Formulations by Dual Centrifugation." Pharmaceuticals 16, no. 11 (2023): 1519. http://dx.doi.org/10.3390/ph16111519.
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Dual centrifugation (DC) is an innovative in-vial homogenization and in-vial nanomilling technique that has been in use for the preparation of liposomes for more than one decade. Since then, DC has continuously been developed for preparing various liposomes and other lipid nanoparticles including emulsions and solid lipid nanoparticles (SLNs) as well as polymersomes and nanocrystals. Improvements in equipment technology have been achieved over the past decade, so that DC is now on its way to becoming the quasi-standard for the simple, fast, and aseptic production of lipid nanoparticles and nanocrystals in small and medium batch sizes, including the possibility of simple and fast formulation screening or bedside preparations of therapeutic nanoparticles. More than 68 publications in which DC was used to produce nanoparticles have appeared since then, justifying an initial review of the use of DC for pharmaceutical nanotechnology.
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Niwa, Rieko, Shigenobu Yoshida, Naruto Furuya, Kenichi Tsuchiya, and Seiya Tsushima. "Method for simple and rapid enumeration of total epiphytic bacteria in the washing solution of rice plants." Canadian Journal of Microbiology 57, no. 1 (2011): 62–67. http://dx.doi.org/10.1139/w10-101.
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The phyllosphere is one of the most common habitats for terrestrial bacteria. However, little is known about the populations of bacteria, including unculturable bacteria, that thrive on plant surfaces. Here, we developed a fluorescent nuclear staining technique to easily and rapidly observe and enumerate populations of total and living epiphytic bacteria, with particular emphasis on the concentration by centrifugation and fixation of the epiphytic bacteria. An investigation on the optimal conditions for centrifugation and fixation revealed that centrifugation at 20 400g for 2 min and fixation with 0.5% glutaraldehyde solution were the optimum conditions for observation of the bacteria. Using this technique, we assessed the populations of the total and living bacteria on the surface of rice plants. When epiphytic bacteria were recovered from rice seeds ( Oryza sativa ‘Koshihikari’), the number of total and living bacterial cells was 7.36 and 6.85 log10·g–1(fresh mass) in the seed washing, respectively. In contrast, the numbers of total and living bacterial cells in the leaf sheath washings were 5.5–5.8 and 5.3–5.7 log10·g–1, respectively. Approximately 5%–30% of the total bacteria in the washing solution of rice plant were culturable. The usefulness of the enumeration method and the amount of bacteria on the plant surfaces are discussed.