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The harvesting process is a current challenge for the commercial production of microalgae because the biomass is diluted in the culture medium. Several methods have been proposed to harvest microalgae cells, but there is not a consensus about the optimum method for such application. Herein, the methods based on sedimentation, flocculation, and centrifugation were evaluated on the recovery of Chlorella sorokiniana BR001 cultivated in a low-nitrogen medium. C. sorokiniana BR001 was cultivated using a low-nitrogen medium to trigger the accumulation of neutral lipids and neutral carbohydrates. The biomass of C. sorokiniana BR001 cultivated in a low-nitrogen medium showed a total lipid content of 1.9 times higher (23.8 ± 4.5%) when compared to the biomass produced in a high-nitrogen medium (12.3 ± 1.2%). In addition, the biomass of the BR001 strain cultivated in a low-nitrogen medium showed a high content of neutral carbohydrates (52.1 ± 1.5%). The natural sedimentation-based process was evaluated using a sedimentation column, and it was concluded that C. sorokiniana BR001 is a non-flocculent strain. Therefore, it was evaluated the effect of different concentrations of ferric sulfate (0.005 to 1 g L-1) or aluminum sulfate (0.025 to 0.83 g L-1) on the flocculation process of C. sorokiniana BR001, but high doses of flocculant agents were required for an efficient harvest of biomass. It was evaluated the centrifugation at low speed (300 to 3,000 g) as well, and it was possible to conclude that this process was the most adequate to harvest the non-flocculent strain C. sorokiniana BR001. [ABSTRACT FROM AUTHOR]

PRP is an autologous product derived from the whole blood of the animal, in it we find high platelet concentration with several growth factors. The classic method for obtaining it is by collecting the blood in tubes with anticoagulant followed for a process of two centrifugations. It has been used as a catalyst in cicatricial processes in various tissues such as the chondral, ligamentous, tendinous, bony, muscular and bony. The present work dealt with a bibliographical research in which it was carried out through the consultation of periodicals, books and oline databases. This study aimed to show by means of a literature review the effectiveness of PRP in inflammatory diseases such as tendinitis / defibrillation in the equine species, as well as to determine the best method of obtaining and how to use it in the different diseases, arriving at a conclusion that a concentration of 300,000 platelets / µL for PRP to be satisfactory in inflammatory treatments. [ABSTRACT FROM AUTHOR]

Three commercial kits of One-Step RT-qPCR were evaluated for the molecular diagnosis of Canine Distemper Virus. Using the kit that showed better performance, two systems of Realtime RT-PCR (RT-qPCR) assays were tested and compared for analytical sensitivity to Canine Distemper Virus RNA detection: a One-Step RT-qPCR (system A) and a One-Step RT-qPCR combined with NESTED-qPCR (system B). Limits of detection for both systems were determined using a serial dilution of Canine Distemper Virus synthetic RNA or a positive urine sample. In addition, the same urine sample was tested using samples with prior centrifugation or ultracentrifugation. Commercial kits of One-Step RT-qPCR assays detected canine distemper virus RNA in 10 (100%) urine samples from symptomatic animals tested. The One-Step RT-qPCR kit that showed better results was used to evaluate the analytical sensitivity of the A and B systems. Limit of detection using synthetic RNA for the system A was 11 RNA copies μL-1 and 110 RNA copies μl-1 for first round System B. The second round of the NESTED-qPCR for System B had a limit of detection of 11 copies μl-1. Relationship between Ct values and RNA concentration was linear. The RNA extracted from the urine dilutions was detected in dilutions of 10-3 and10-2 by System A and B respectively. Urine centrifugation increased the analytical sensitivity of the test and proved to be useful for routine diagnostics. The One-Step RTqPCR is a fast, sensitive and specific method for canine distemper routine diagnosis and research projects that require sensitive and quantitative methodology. [ABSTRACT FROM AUTHOR]

The effects of the centrifugation associated to the use of two extenders on the viability of six-banded armadillo's (Euphractus sexcinctus) sperm were evaluated during a thermo resistance test (TRT). Semen samples (n=12) derived from 04 stud males collected by electroejaculation were divided in four aliquots; two of that were immediately diluted in Tris or powdered coconut water (ACP-119®); the two others were centrifuged (800g 10min-1) prior to the dilution. Samples were incubated at 34°C per 3h, and the semen parameters were evaluated at each hour. In general, dilution promoted a reduction in semen viscosity in the use of both diluents using centrifugation or not. At 60min, a decrease was verified for all semen parameters (P<0.05), however they were better preserved in the use of Tris when compared to ACP-119® (P<0.05) up to 120min. After that, both diluents equated. In addition, centrifugation procedure presented a deleterious effect on the armadillo s semen quality during all the thermoresistance test. In the present conditions, conclude that Tris extender is more efficient than ACP-119® for the preservation of six-banded armadillo semen viability, and the previous centrifugation is unnecessary. [ABSTRACT FROM AUTHOR]

PRP is plasma that contains a high numbers of platelets and growth factors in a small volume. The aim of this study was to evaluate seven different protocols to obtain PRP by the manual method according to their capacity to concentrate platelets, leukocyte and erythrocyte contamination and correlation between platelet count and TGF-β1 growth factor levels in PRP samples. Ten healthy horses with a mean age of 7 years (±2.39), weighing on average 500 kg (±67.1) were used in this study. The protocols tested varied according to the speed and time used at the two centrifugations. PRP samples were analyzed regarding platelet concentration, leukocyte and erythrocyte contamination and TGF-β1 levels quantified by ELISA. No significant differences among protocols were observed regarding the ability to concentrate platelets and TGF-β1 . However, protocol I showed significantly higher erythrocyte and leukocyte counts in PRP samples than the other protocols, reason why it was considered inadequate for the volume of blood processed in this experiment. The remaining protocols are suitable for extracting PRP. [ABSTRACT FROM AUTHOR]