Surveillance for Yellow Fever Virus in Non-Human Primates in Southern Brazil, 2001–2011: A Tool for Prioritizing Human Populations for Vaccination

In Brazil, epizootics among New World monkey species may indicate circulation of yellow fever (YF) virus and provide early warning of risk to humans. Between 1999 and 2001, the southern Brazilian state of Rio Grande do Sul initiated surveillance for epizootics of YF in non-human primates to inform vaccination of human populations. Following a YF outbreak, we analyzed epizootic surveillance data and assessed YF vaccine coverage, timeliness of implementation of vaccination in unvaccinated human populations. From October 2008 through June 2009, circulation of YF virus was confirmed in 67 municipalities in Rio Grande do Sul State; vaccination was recommended in 23 (34%) prior to the outbreak and in 16 (24%) within two weeks of first epizootic report. In 28 (42%) municipalities, vaccination began more than two weeks after first epizootic report. Eleven (52%) of 21 laboratory-confirmed human YF cases occurred in two municipalities with delayed vaccination. By 2010, municipalities with confirmed YF epizootics reported higher vaccine coverage than other municipalities that began vaccination. In unvaccinated human populations timely response to epizootic events is critical to prevent human yellow fever cases.     

High Levels of Soluble Ctla-4 Are Present in Anti-Mitochondrial Antibody Positive,but Not in Antibody Negative Patients with Primary Biliary Cirrhosis

Primary biliary cirrhosis (PBC) is a chronic autoimmune cholestatic liver disease frequently characterized by anti-mitochondrial autoantibodies (AMA). A minority of patients are AMA-negative. Cytotoxic-T-Lymphocyte-Antigen-4 (CTLA-4) is a surface molecule expressed on activated T-cells delivering a critical negative immunoregulatory signal. A soluble form of CTLA-4 (sCTLA-4) has been detected at high concentrations in several autoimmune diseases, and its possible functional meaning has been suggested. We aimed to evaluate sCTLA-4 concentration in sera of patients with PBC and to correlate it to immunological abnormalities associated with the disease. Blood samples were collected from 82 PBC-patients diagnosed according to international criteria (44 AMA-positive/MIT3-positive and 38 AMA-negative-MIT3-negative), and 65 controls. sCTLA-4 levels were evaluated by ELISA and Western blot. Increased sCTLA-4 concentrations were found in all AMA-positive PBC-patients, but in none of the AMA-negative ones, nor in normal controls or in controls with unrelated liver diseases. sCTLA-4 presence was associated with autoantibodies against MIT3, but not with nuclear autoantibodies (sp100, gp210). This is the first study to demonstrate that levels of sCTLA-4 are elevated in sera of PBC patients. However, they are clearly restricted to patients with AMA positivity, suggesting an immunological difference with respect to AMA-negative ones.     

Effect of a povidone-iodine intrauterine infusion on progesterone levels and endometrial steroid receptor expression in mares

Background  

Intrauterine infusions have been widely used for the treatment of endometritis in the mare. Nevertheless, their consequences on endocrine and endometrial molecular aspects are unknown. We studied the effect of a 1% povidone-iodine solution intrauterine infusion on progesterone levels, endometrial histology and estrogen (ERα) and progesterone (PR) receptor distribution by immunohistochemistry.     

Suppression of Autophagy in Osteocytes Mimics Skeletal Aging

Bone mass declines with age but the mechanisms responsible remain unclear. Here we demonstrate that deletion of a conditional allele for Atg7, a gene essential for autophagy, from osteocytes caused low bone mass in 6-month-old male and female mice. Cancellous bone volume and cortical thickness were decreased, and cortical porosity increased, in conditional knock-out mice compared with control littermates. These changes were associated with low osteoclast number, osteoblast number, bone formation rate, and wall width in the cancellous bone of conditional knock-out mice. In addition, oxidative stress was higher in the bones of conditional knock-out mice as measured by reactive oxygen species levels in the bone marrow and by p66^shc phosphorylation in L6 vertebra. Each of these changes has been previously demonstrated in the bones of old versus young adult mice. Thus, these results demonstrate that suppression of autophagy in osteocytes mimics, in many aspects, the impact of aging on the skeleton and suggest that a decline in autophagy with age may contribute to the low bone mass associated with aging.     

Osteocytes,not Osteoblasts or Lining Cells,are the Main Source of the RANKL Required for Osteoclast Formation in Remodeling Bone

The cytokine receptor activator of nuclear factor kappa B ligand (RANKL), encoded by the Tnfsf11 gene, is essential for osteoclastogenesis and previous studies have shown that deletion of the Tnfsf11 gene using a Dmp1-Cre transgene reduces osteoclast formation in cancellous bone by more than 70%. However, the Dmp1-Cre transgene used in those studies leads to recombination in osteocytes, osteoblasts, and lining cells making it unclear whether one or more of these cell types produce the RANKL required for osteoclast formation in cancellous bone. Because osteoblasts, osteocytes, and lining cells have distinct locations and functions, distinguishing which of these cell types are sources of RANKL is essential for understanding the orchestration of bone remodeling. To distinguish between these possibilities, we have now created transgenic mice expressing the Cre recombinase under the control of regulatory elements of the Sost gene, which is expressed in osteocytes but not osteoblasts or lining cells in murine bone. Activity of the Sost-Cre transgene in osteocytes, but not osteoblast or lining cells, was confirmed by crossing Sost-Cre transgenic mice with tdTomato and R26R Cre-reporter mice, which express tdTomato fluorescent protein or LacZ, respectively, only in cells expressing the Cre recombinase or their descendants. Deletion of the Tnfsf11 gene in Sost-Cre mice led to a threefold decrease in osteoclast number in cancellous bone and increased cancellous bone mass, mimicking the skeletal phenotype of mice in which the Tnfsf11 gene was deleted using the Dmp1-Cre transgene. These results demonstrate that osteocytes, not osteoblasts or lining cells, are the main source of the RANKL required for osteoclast formation in remodeling cancellous bone.     

Sphingosine 1-phosphate promotes antigen processing and presentation to CD4+ T cells in Mycobacterium tuberculosis-infected monocytes

It was previously shown that cells die with increased cytosolic ATP after stimulation with apoptotic inducers including staurosporine (STS). To identify the source of apoptotic ATP elevation, we monitored, in real time, the cytosolic ATP level in luciferase-expressing HeLa cells. A mitochondrial uncoupler or a respiration chain inhibitor was found to decrease cytosolic ATP by about 50%. However, even when mitochondrial ATP synthesis was suppressed, STS induced a profound elevation of intracellular ATP. In contrast, the STS-induced ATP increase was prevented by any of three inhibitors of the glycolytic pathway: 2-deoxyglucose, iodoacetamide, and NaF. The STS effect strongly depended on intracellular calcium and was mimicked by a calcium ionophore. We conclude that Ca(2+)-dependent activation of anaerobic glycolysis, but not aerobic mitochondrial oxidative phosphorylation, is responsible for the STS-induced elevation of ATP in apoptotic HeLa cells.     

Effect of the relation between neural cholinergic action and nitric oxide on ovarian steroidogenesis in prepubertal rats

The coeliac ganglion and the ovary are related by the superior ovarian nerve, which penetrates into the ovary by the hilium and innervates mainly the ovarian stroma. On the other hand, it is known that the gaseous neurotransmitter nitric oxide (NO) and the two isoforms of its synthesis enzyme, the nitric oxide synthetase (NOS), are present in the ovary. Both innervation and NO participate in ovarian steroidogenesis. Therefore, the purposes of this work were (a) to standardize an in vitro coeliac ganglion-superior ovarian nerve-ovary integrated system in prepubertal rats; (b) to determine the presence of NO in the ovary and analyze the ganglionic cholinergic effect on the ovarian release of androstenedione, progesterone and NO; and (c) to assess the steroids/NO relationship. The system was incubated in buffer solution for 120 min, with the ganglion and ovary located in different compartments and linked by the superior ovarian nerve. From the results obtained, it is concluded that the system is viable and functional. The presence of basal NO is stimulated by the cholinergic action, while the release of the steroids is inhibited, which might indicate that the ganglionic cholinergic effect is probably mediated by NO. To our knowledge, this work constitutes the first study of the relationship between the neural cholinergic action and NO on the ovarian steroidogenesis of prepubertal rats.