Repair of blood vessels after viral lung injury is achieved by resident endothelial cells and requires COUP-TF2.

Costa MF, et al. J Vet Sci. 2011 Mar;12(1):21-25. http://dx.doi.org/10.4142/jvs.2011.12.1.21

Angiotensin II is a key regulator of blood pressure and cardiovascular function in mammals. The conversion of angiotensin into its active form is carried out by Angiotensin I-Converting Enzyme (ACE). The measurement of ACE concentration in plasma or serum, its enzymatic activity, and the correlation between an insertion/deletion (I/D) genetic polymorphism of the ACE gene have been investigated as possible indicators of superior athletic performance in humans. In this context, other indicators of superior adaptation to exercise resulting in better athletic performance (such as ventricular hypertrophy, VO₂ max, and competition results) were mostly used to study the association between ACE I/D polymorphism and improved performance. Despite the fact that the existing literature presents little consensus, there is sufficient scientific evidence to warrant further investigation on the usage of ACE activity and the I/D ACE gene polymorphism as biomarkers of superior athletic performance in humans of specific ethnicities or in athletes involved in certain sports. In this sense, a biomarker would be a substance or genetic component that could be measured to provide a degree of certainty, or an indication, of the presence of a certain trait or characteristic that would be beneficial to the athlete’s performance. Difficulties in interpreting and comparing the results of scientific research on the topic arise from dissimilar protocols and variation in study design. This review aims to investigate the current literature on the use of ACE I/D polymorphism as a biomarker of performance in humans through the comparison of scientific publications.

This study compared two protocols for preparation of platelet rich plasma (PRP) and evaluated the association between manual and automated methods for platelet count using a prospective study design. Eight clinically healthy Quarter Horses had venous blood samples collected at rest. After collection, blood samples were centrifuged twice, using two different protocols including a period of sample resting, either at the start or at the end of the protocol. Platelet counting at the start of the protocol, during, and after obtaining PRP was conducted manually or with an automated counter, followed by comparison of the two methods. In order to investigate platelet degranulation during the protocol, vascular endothelial growth factor (VEGF) was measured at each preparation stage. The protocol with sample resting before centrifugation yielded a more concentrated PRP, and the study verified that both manual and automated methods are comparable and can be used interchangeably for platelet counting. VEGF concentration did not differ significantly between protocols, or among protocol stages. The results indicate that choice of protocol for PRP preparation will affect the quantity of platelets in the final product, although platelet degranulation was not observed as evidenced by the stable VEGF concentrations measured. A larger yield of non-degranulated platelets in PRP is desirable since more α-granules will be present, therefore Protocol II is recommended. Both manual and automated counts reliably allow clinicians to obtain platelet counts and the choice of utilizing a manual or automated method is unlikely to interfere with evaluation of the final PRP product.

Platelet rich plasma (PRP) is an autologous biological product harvested by consecutive centrifugations of whole blood and separation of plasma in a stepwise protocol. PRP has been successfully used to stimulate healing in orthopedic and dermatological conditions, both in humans and animals. The principle is the fact that α- granules inside platelets contain a high concentration of growth factors, that once released can interfere with cellular communication and speed up healing. Standardization of PRP requires establishing a gold standard for the preparation and evaluation of the product, especially considering that platelet concentration and, therefore, growth factor concentration, might vary due to a number of variables. Factors such as age, gender, race or breed, and immune status of the patient might interfere with PRP quality and with treatment results, although little is known about such interferences. This research investigated the effect of breed/species and gender in platelet concentration in autologous PRP from horses and mules. The results demonstrate that Quarter Horses provided PRP with the greatest amount of platelets, although mules had a higher concentration percentages in relation to the initial platelet counts.