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Objective To describe the benefits obtained through South-South and triangular cooperation as a potential tool for strengthening medicine quality control in official medicines control laboratories (OMCLs) of the Region of the Americas. Methods Descriptive study of the project for strengthening drug quality control in OMCLs of the Caribbean community (CARICOM). Results Staff members of Argentina's National Administration for Drugs, Food, and Medical Technology (ANMAT) provided training to professionals from Guyana, Jamaica, Suriname, and Trinidad and Tobago. The project was funded by the Argentine Fund for South-South and Triangular Cooperation (FO.AR) and coordinated by the Pan American Health Organization (PAHO). Documents on good laboratory practice (GLP) developed by the World Health Organization (WHO) and the Pan American Network for Drug Regulatory Harmonization (PANDRH) were reviewed, and the area of physical and chemical controls was strengthened, primarily for drugs to treat tuberculosis, malaria, and HIV/AIDS, all of which are strategically important to those countries. Conclusion This type of collaboration makes it possible to share experiences, optimize resources, harmonize procedures and regulations, and strengthen human resource capacities. In addition, it is a valuable tool for reducing asymmetries in various areas among the different countries of our Region.

Leukocyte migration is essential for the function of the immune system. Their recruitment from the vessels to the tissues involves sequential molecular interactions between leukocytes and endothelial cells (ECs). Many adhesion molecules involved in this process have already been described. However, additional molecules may be important in this interaction, and here we explore the potential role for CD100 and plexins in monocyte-EC binding. CD100 was shown to be involved in platelet-endothelial cell interaction, an important step in atherogenesis and thrombus formation. In a recent work we have described CD100 expression in monocytes and in macrophages and foam cells of human atherosclerotic plaques. In the present work, we have identified plexin B2 as a putative CD100 receptor in these cells. We have detected CD100 expression in the endothelium as well as in in vitro cultured endothelial cells. Blocking of CD100, plexin B1 and/or B2 in adhesion experiments have shown that both CD100 and plexins act as adhesion molecules involved in monocyte-endothelial cell binding. This effect may be mediated by CD100 expressed in both cell types, probably coupled to the receptors endothelial plexin B1 and monocytic plexin B2. These results can bring new insights about a possible biological activity of CD100 in monocyte adhesion and atherosclerosis, as well as a future candidate for targeting therapeutics., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Long-term non-progressors (LTNP) represent a minority (1-5%) of HIV-infected individuals characterized by documented infection for more than 7-10 years, a stable CD4+ T cell count over 500/mm(3) and low viremia in the absence of antiretroviral treatment. Protective factors described so far such as the CCR5delta32 deletion, protective HLA alleles, or defective viruses fail to fully explain the partial protection phenotype. The existence of additional host resistance mechanisms in LTNP patients was investigated here using a whole human genome microarray study comparing gene expression profiles of unstimulated peripheral blood mononuclear cells from LTNP patients, HIV-1 infected patients under antiretroviral therapy with CD4+ T cell levels above 500/mm(3) (ST), as well as healthy individuals. Genes that were up- or downregulated exclusively in LTNP, ST or in both groups in comparison to controls were identified and classified in functional categories using Ingenuity Pathway Analysis. ST and LTNP patient groups revealed distinct genetic profiles, regarding gene number in each category and up- or downregulation of specific genes, which could have a bearing on the outcome of each group. We selected some relevant genes to validate the differential expression using quantitative real-time qRT-PCR. Among others, we found several genes related to the canonical Wnt/beta-catenin signaling pathway. Our results identify new possible host genes and molecules that could be involved in the mechanisms leading to the slower progression to AIDS and sustained CD4+ T cell counts that is peculiar to LTNP patients., (Copyright © 2014. Published by Elsevier Ltd.)

Atherosclerosis is a complex disease in which vessels develop plaques comprising dysfunctional endothelium, monocyte derived lipid laden foam cells and activated lymphocytes. Considering that humans and animal models of the disease develop quite distinct plaques, we used human plaques to search for proteins that could be used as markers of human atheromas. Phage display peptide libraries were probed to fresh human carotid plaques, and a bound phage homologous to plexin B1, a high affinity receptor for CD100, was identified. CD100 is a member of the semaphorin family expressed by most hematopoietic cells and particularly by activated T cells. CD100 expression was analyzed in human plaques and normal samples. CD100 mRNA and protein were analyzed in cultured monocytes, macrophages and foam cells. The effects of CD100 in oxLDL-induced foam cell formation and in CD36 mRNA abundance were evaluated. Human atherosclerotic plaques showed strong labeling of CD100/SEMA4D. CD100 expression was further demonstrated in peripheral blood monocytes and in in vitro differentiated macrophages and foam cells, with diminished CD100 transcript along the differentiation of these cells. Incubation of macrophages with CD100 led to a reduction in oxLDL-induced foam cell formation probably through a decrease of CD36 expression, suggesting for the first time an atheroprotective role for CD100 in the human disease. Given its differential expression in the numerous foam cells and macrophages of the plaques and its capacity to decrease oxLDL engulfment by macrophages we propose that CD100 may have a role in atherosclerotic plaque development, and may possibly be employed in targeted treatments of these atheromas.

The aims of the present study were to investigate the effects of follicle-stimulating hormone (FSH) on survival, activation and growth of caprine primordial follicles using histological and ultrastructural studies. Pieces of caprine ovarian cortex were cultured for 1 or 7 days in minimum essential medium (MEM - control medium) supplemented with different concentrations of FSH (0, 10, 50 or 100 ng/ml). Small fragments from non-cultured ovarian tissue and from those cultured for 1 or 7 days in a specific medium were processed for classical histology and transmission electron microscopy (TEM). Additionally, effects of FSH on oocyte and follicle diameter of cultured follicles were evaluated. The results showed that the lowest percentage of normal follicles was observed after 7 days of culture in control medium. After 1 day of culture, a higher percentage of growing follicles was observed in the medium supplemented with 50 ng/ml of FSH. In the presence of 10 and 50 ng/ml of FSH, an increase in diameter of both oocyte and follicle on day 7 of culture was observed. TEM showed ultrastructural integrity of follicles after 1 day of culture in MEM and after 7 days in MEM plus 50 ng/ml FSH, but did not confirm the integrity of those follicles cultured for 7 days in MEM. In conclusion, this study demonstrated that FSH at concentration of 50 ng/ml not only maintains the morphological integrity of 7 days cultured caprine preantral follicles, but also stimulate the activation of primordial follicles and the growth of activated follicles.

The main objective of the present study was to characterize buffalo preantral ovarian follicles. Parts of ovarian cortex, collected from postpubertal buffalo females that were having estrous cycles at regular intervals, were selected under stereomicroscopy and processed for optic and transmission electron microscopy. Primordial follicles were characterized as an oocyte encircled by one layer of flattened cells. The buffalo primordial follicle has a mean diameter of 35 microm and the oocyte diameter is 24.9 microm. The oocyte nucleus is relatively large and eccentric; and in the cytoplasm a large amount of mitochondria, vesicles and endoplasmic reticulum cistern, mainly of the smooth type is observed. The primordial follicles cells are rich in plasma membrane invaginations, which are observed within the cell and between the cell and the oocyte. The primary follicles (mean diameter of 41.8 microm) consist of an oocyte, with a medium diameter of 26.9 microm, surrounded by one layer of cubical granulosa cells. At this follicular stage, the beginning of zona pellucida deposition can also be seen in areas between the oocyte and follicular cells. The secondary follicles, which are surrounded by more than one layer of cubical cells, have a diameter of 53.3 microm, and the oocyte has a mean diameter of 29.4 microm. The ultrastructural analysis showed a large amount of coalescent vesicles, more evident in the oocyte periphery. The zona pellucida (ZP) is thicker at this stage and contains a large quantity of glycoproteins. In general, the ultrastructure of buffalo preantral follicles was similar to that of other mammalian species, but some differences were observed, which indicate species specific characteristics. The main differences observed were cytoplasmic vesicles quantity, mitochondria shape and inner content, ZP deposition and granulosa cell-oocyte junctions. In conclusion, the morphological differences described in this paper, could be responsible for some functional differences observed in Bubalus bubalis in vitro embryo production and follicular dynamics, when compared with Bos taurus or Bos indicus species.

The aims of the present study were to evaluate the effects of fibroblast growth factor-2 (FGF-2) on survival, activation and growth of caprine early-staged (preantral) follicles using histological and ultrastructural studies. Fragments of caprine ovarian cortex were cultured for 1 or 5 days in an enriched minimum essential medium, supplemented or not with different concentrations of FGF-2 (10, 50 or 100 ng/ml). Fragments from non-cultured ovarian tissue (control) and from tissues cultured for 1 or 5 days in a specific medium were processed for transmission electron microscopy (TEM) or classical histology to evaluate the morphological quality of caprine preantral follicles and to calculate the percentages of normal follicles. Additionally, effects of FGF-2 on oocyte and follicle diameter of cultured preantral follicles were investigated. Our results showed that, although the percentages of histologically normal follicles were lower in cultured than in non-cultured ovarian tissue fragments, there were no differences in this regard among treatments, neither on day 1 nor on day 5 of culture. After 1 and 5 days of culture, a significantly higher percentage of growing follicles was observed in the medium supplemented with 50 ng/ml of FGF-2. This FGF-2 treatment furthermore resulted in an increase in diameter of both oocytes and follicles that were cultured for 5 days. TEM showed that the ultrastructural integrity of caprine preantral follicles was maintained during their 5-day culture in the presence of 50 ng/ml FGF-2. In conclusion, this study demonstrated that at a concentration of 50 ng/ml FGF-2 not only maintains the morphological integrity of caprine preantral follicles cultured for 5 days, but also stimulates the activation of primordial follicles and the growth of activated follicles., (Copyright 2007 S. Karger AG, Basel.)

The ultrastructure of normal, ejaculated spermatozoa of Bos indicus was studied by means of electron microscopy, being evaluated in two principal parts, the head and the tail. The head is flat, oval or paddle-shaped with a square base, which provides a concave recess for the insertion of the tail. The acrosome tightly covers the anterior two thirds of the nucleus. A distinct unilateral acrosomal bulge was observed along the apical edge of the head. The equatorial region demarcates the acrosome from the post-equatorial region that covers the caudal one third of the nucleus. The classical 9+9+2 fiber pattern which composes the axoneme was observed along three segments of the tail, namely middle, principal and terminal pieces. The axoneme is anteriorly bound by the mitochondrial helix (middle piece) and posteriorly by the fibrous helix (principal piece), except at the terminal piece. The border between the middle piece and principal piece was well defined due to the termination of the thick mitochondrial helix and the presence of the annulus. Some of the spermatozoa presented cytoplasmatic droplets, which appeared as stalk-like appendages.

The aim of the present study was to characterize the ultrastructure of zebu cow preantral follicles (PAFs). Ovarian cortex samples were processed for light and transmission electron microscopy. Primordial follicles consisted of an oocyte surrounded by one layer of flattened or flattened-cuboidal granulosa cells. The oocyte contained a large and usually eccentric nucleus. Most organelles were located at the perinuclear ooplasm. Round shaped mitochondria, which contained electron-dense granules, smooth and rough endoplasma reticulum and a Golgi apparatus were also observed. Vesicles and coated pits were often observed in the cortical ooplasm. In primary follicles, the oocyte was surrounded by one layer of cuboidal granulosa cells. Short microvilli were observed on the oolema. Secondary follicles consisted of an oocyte surrounded by a variable number of layers of cuboidal granulosa cells. Small secondary follicles had an ultrastructure very similar to that observed in primary follicles. At this follicular stage, the zona pellucida was beginning to form around the oocyte. In large secondary follicles, the zona pellucida was totally developed around the oocyte. Several granulosa cell projections could be detected that were encroaching into the zona pellucida and protruding towards the oocyte, where gap junctions were observed between oocyte and granulosa cell membranes. Organelles within the oocyte were located at the periphery of the ooplasm, and clusters of cortical granules were observed. Round mitochondria were abundant in all developmental stages. In conclusion, this study described the ultrastructure of zebu cow PAFs, and some unique characteristics could be observed as compared with what has been reported for follicles of Bos taurus cattle.