Linking genetic and environmental factors in amphibian disease risk

A central question in evolutionary biology is how interactions between organisms and the environment shape genetic differentiation. The pathogen Batrachochytrium dendrobatidis (Bd) has caused variable population declines in the lowland leopard frog (Lithobates yavapaiensis); thus, disease has potentially shaped, or been shaped by, host genetic diversity. Environmental factors can also influence both amphibian immunity and Bd virulence, confounding our ability to assess the genetic effects on disease dynamics. Here, we used genetics, pathogen dynamics, and environmental data to characterize L.yavapaiensis populations, estimate migration, and determine relative contributions of genetic and environmental factors in predicting Bd dynamics. We found that the two uninfected populations belonged to a single genetic deme, whereas each infected population was genetically unique. We detected an outlier locus that deviated from neutral expectations and was significantly correlated with mortality within populations. Across populations, only environmental variables predicted infection intensity, whereas environment and genetics predicted infection prevalence, and genetic diversity alone predicted mortality. At one locality with geothermally elevated water temperatures, migration estimates revealed source-sink dynamics that have likely prevented local adaptation. We conclude that integrating genetic and environmental variation among populations provides a better understanding of Bd spatial epidemiology, generating more effective conservation management strategies for mitigating amphibian declines.

Optimal clearance of Sporothrix schenckii requires an intact Th17 response in a mouse model of systemic infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Disease resistance of pacu Piaractus mesopotamicus (Holmberg, 1887) fed with beta-glucan

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Gallus gallus domesticus are resistant to infection with Neospora caninum tachyzoites of the NC-1 strain

The aim of this study was to experimentally evaluate infection in Gallus gallus domesticus with Neospora caninum tachyzoites of the NC-1 strain. Experimental infection was conducted in 90-day-old chickens, embryonated eggs and bioassays in dogs. In the first experiment, poults were randomly divided into four groups. Groups I and II were provided feed with coccidiostat, whereas groups III and IV received feed without coccidiostat. When the poults from groups I and III reached 90 days of age, they received a subcutaneous inoculation of N. caninum. Once the hens entered their egg-laying period, during the following 30 days, the eggs were collected, identified, weighed and placed in an incubator. On the 70th day after inoculation, all animals, including the chicks, were euthanized. Tissue samples from the adult poultry and chicks were collected for histopathology, immunohistochemistry (IHC) and PCR. Brain tissue and pectoral muscle samples from infected birds were fed to two dogs. Notably, the average weight of the group III eggs was lower than that of the group IV eggs (p <0.05). No changes consistent with infection in adult poultry or chicks were detected by histopathology or IHC; moreover, no amplified parasite DNA was detected in the birds'tissues or dogs'feces. No dog eliminated oocysts. In the second experiment, the embryonated chicken eggs were inoculated with 1 x 10(2) N. caninum tachyzoites, on the 10th day of incubation, and chicks born from these eggs were housed in boxes suitable for the species and received commercial feed and distilled water ad libitum. On the 30th day after infection (DAI), the poultry were euthanized, and their organs were processed as described in experiment I. The amplification of parasite DNA was observed in the spleen and pectoral muscles of one of the birds. The ingestion of bird tissues by dogs did not result in oocyst elimination. These results indicate that the parasite may have been eliminated by the host and that the use of tachyzoites to induce chronic disease might be a poor source for hens. (C) 2014 Elsevier B.V. All rights reserved.

Galectin-1 exerts inhibitory effects during DENV-1 infection

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Aspects of toxoplasma infection on the reproductive system of experimentally infected rams (ovis aries)

Eight reproductive rams with no prior reproductive disease were distributed into three groups of infection with T. gondii: GI, 3 rams, 2.0 x 10(5) P strain oocysts; GII, 3 rams, 1.0 x 10(6) RH strain tachyzoites; GIII, 2 control rams. Clinical parameters were measured and serological evaluations (IIF) were performed. Presence of the parasite in the semen was investigated by PCR and bioassay techniques. The rams presented clinical alterations (hyperthermia and apathy) related to toxoplasmosis in both groups infected with Toxoplasma gondii. All the inoculated rams responded to antigenic stimulus, producing antibodies against T. gondii from postinoculation day 5 onwards. In ovine groups I and II, the greatest titers observed were 1 : 4096 and 1 : 8192, respectively. In semen samples collected from these two groups, the presence of T. gondii was detected by bioassay and PCR. This coccidian was isolated (bioassay and PCR) in tissue pools (testicles, epididymis, seminal vesicle, and prostrate) from two rams infected presenting oocysts and in one presenting tachyzoites.

Nutritional status and immune response in murine experimental Jorge Lobo's disease

There are no studies investigating the role of nutritional status and immunity associated with Jorge Lobo's disease. The objective of this study was to evaluate the effects of protein-calorie malnutrition on the immune response of BALB/c mice inoculated with Lacazia loboi. In this study,the animals were divided into four groups: G1: inoculated with restricted diet, G2: not inoculated with restricted diet, G3: inoculated with regular diet, G4: not inoculated with regular diet. The animals of groups G1 and G2 were submitted to malnutrition for 20 days and once installed the animals were inoculated intradermally into the footpad. After 4 months, they were euthanised for the isolation of peritoneal lavage cells and removal of the footpad. The production of IL-2, IL-4, IL-10, IL-12, IFN-γ, TNF-α, H2 O2 and nitric oxide (NO) was evaluated in the peritoneal lavage cells. The footpad was evaluated regarding the size of macroscopic lesions, number of fungi and viability index. The results showed that the infection did not exert great influence on the body weight of the mice and previous malnutrition was an unfavourable factor for viability index, number of fungi, macroscopic lesion size in the footpad and production of H2 O2 , NO, IL-12, IL-10 and IFN-γ, suggesting that malnutrition significantly altered fungal activity and peritoneal cells. The results suggest considerable interaction between nutrition and immunity in Jorge Lobo's disease.

Characterization of Trypanosoma cruzi Sirtuins as Possible Drug Targets for Chagas Disease

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Correlation between volume of apical periodontitis determined by cone-beam computed tomography analysis and endotoxin levels found in primary root canal infection

This clinical study was conducted to correlate the levels of endotoxins and bacterial counts found in primary endodontic infection with the volume of periapical bone destruction determined by cone-beam computed tomography (CBCT) analysis. Moreover, the levels of bacteria and endotoxins were correlated with the development of clinical features. Twenty-four root canals with primary endodontic disease and apical periodontitis were selected. Clinical features such as pain on palpation, pain on percussion, and previous episode of pain were recorded. The volume (cubic millimeters) of periapical bone destruction was determined by CBCT analysis. Endotoxins and bacterial samplings were collected by using sterile/apyrogenic paper points. Endotoxins were quantified by using limulus amebocyte lysate assay (KQCL test), and bacterial count (colony-forming units [CFU]/mL) was determined by using anaerobic culture techniques. Data were analyzed by Pearson correlation and multiple logistic regression (P < .05). Endotoxins and bacteria were detected in 100% of the root canal samples (24 of 24), with median values of 10.92 endotoxin units (EU)/mL (1.75-128 EU/mL) and 7.5 × 10(5) CFU/mL (3.20 × 10(5)-8.16 × 10(6) CFU/mL), respectively. The median volume of bone destruction determined by CBCT analysis was 100 mm(3) (10-450 mm(3)). The multiple regression analysis revealed a positive correlation between higher levels of endotoxins present in root canal infection and larger volume of bone destruction (P < .05). Moreover, higher levels of endotoxins were also correlated with the presence of previous pain (P < .05). Our findings revealed that the levels of endotoxins found in root canal infection are related to the volume of periapical bone destruction determined by CBCT analysis. Moreover, the levels of endotoxin are related to the presence of previous pain.

Hepatitis C infection: challenges in dental management and diagnosis of extrahepatic manifestations

Hepatitis C is associated with autoimmune diseases, hepatocellular carcinoma,and extrahepatic manifestations that, in conjunction, may seriously compromise the patient's quality of life. We herein describe a case of chronic hepatitis C with oral manifestations and discuss some implications for diagnosis and treatment. A 63-year-old woman complaining of spontaneous bleeding of the oral mucosa presented with bilateral asymmetric ulcers surrounded by white papules and striae on the buccal mucosa. Her medical history revealed leucopenia, thrombocytopenia, and skin lesions associated with chronic hepatitis C. Propranolol and ranitidine had recently been prescribed. Lichen planus, lichenoid reaction, and erythema multiforme were considered in the differential diagnosis. Histopathological analysis revealed lymphocytic infiltrate in a lichenoid pattern. The lesions partially healed after 1 week and completely regressed after 6 months, despite the maintenance of all medications; no recurrence was observed. The final diagnosis was oral lichen planus associated with hepatitis C. Chronic hepatitis C may present oral manifestations, which demand adjustments in dental treatment planning. Medication side effects may interfere with the clinical presentation and course of the disease and should be accounted for in the differential diagnosis. The possibility of spontaneous remission of oral lichen planus should always be considered, especially when putative etiological factors of a lichenoid lesion are withdrawn in an attempt to differentiate oral lichen planus from lichenoid lesions. This case emphasizes the importance of recognizing the extrahepatic manifestations of hepatitis C as a cause of increased morbidity.

Study on Chagas disease occurrence in the municipality of Monte Negro, State of Rondônia, Brazilian Amazon

Introduction: Studies on Chagas disease deal with the perspective of its occurrence in the Amazon region, which is directly correlated to the population growth and the spread of the bug biotope. The state of Rondônia has an immense source of vectors (Triatomine) and reservoirs of Trypanosoma cruzi. Environmental changes brought forth by the deforestation in the region may cause vector behavior changes and bring these vectors to a closer contact with humans, increasing the probability of vector infection. Methods: This study was carried out to check the occurrence of Chagas disease in the municipality of Monte Negro, Rondônia, Brazil, based on a random sampling of the farms and people wherein blood collection from the population and capturing triatomines were done. The blood samples were submitted to serologic tests to detect antibodies of the IgG class against T. cruzi. The triatomines that were collected had their digestive tract checked for the presence of trypanosomatidae with morphology resembling that of the T. cruzi. Results: The population examined was mostly from other states. From the 322 bugs examined on the microscope, 50% showed parasites with morphology compatible with T. cruzi. From the serology of 344 random samples of human blood, 1.2% was found positive, 6% showed inconclusive results, and 92.8% were negative. Conclusions: Monte Negro shows low prevalence of human infection by T. cruzi and none active vector transmission; however, preventive and surveying measures, which are not performed until now, shall be taken due to the abundance of vectors infected by trypanosomatidae.

Leishmania sp. infection in dogs from Florianópolis, Santa Catarina, SC, Brazil

The aim of the present study was to investigate the occurrence of Leishmania sp. infection in dogs (N = 491) living in the municipality of Florianópolis, Santa Catarina (SC), Brazil, which was considered a disease-free region for visceral leishmaniasis until 2011, when autochthonous cases of canine disease were notified. Seroprevalence in this population was assessed by ELISA (0.4%; 2/491) and IFAT (4.09%; 24/491). Only one dog exhibited seroreactivity in both serological methods, comprising a total of 25 (5.3%) seroreagent animals. Leishmania sp. DNA, obtained from a sample of whole blood of this animal, was amplified by both conventional and Real-Time PCR. Sequencing of the amplified DNA and, thereby, determination of the Leishmania species involved, was not possible. Our results suggest the necessity of a thorough epidemiological investigation in Florianópolis. (AU).

Borreliosis in horses: epidemiology, experimental infection and therapeutic

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Secondary aspergillus fumigatus infection associated with coloidal goiter in a Black-masked Lovebird (Agapornis personata)

Aspergillosis is caused by fungus of Aspergillus genus. Is a multifactorial secondary disease and occurs mainly to immunodeficiency. Goiter is the name to non-inflammatory and non-neoplasic thyroid growth which affecting the animal metabolism. In this report we describe a case of aspergillosis and colloidal goiter in a male Black-masked lovebird (Agapornis personata) diagnosed by post mortem exam. The bird was presented for examination due to severe respiratory signs. An initial palliative treatment was performed in order to relieve the symptoms. Despite this, the patient came to die without performing additional ancillary tests. On gross exam, a pulmonary nodule was observed from which we were able to isolate Aspergillus fumigatus on microbial culture. Histological assessment revealed pulmonary aspergilosis and colloid goiter. Based on histopathological and microbiological assessments we conclude that infection probably was secondary to colloid goiter.