BAG3 regulates total MAP1LC3B protein levels through a translational but not transcriptional mechanism

Autophagy is mainly regulated by post-translational and lipid modifications of ATG proteins. In some scenarios, the induction of autophagy is accompanied by increased levels of certain ATG mRNAs such as MAP1LC3B/LC3B, ATG5 or ATG12. However, little is known about the regulation of ATG protein synthesis at the translational level. The cochaperone of the HSP70 system BAG3 (BCL2-associated athanogene 3) has been associated to LC3B lipidation through an unknown mechanism. In the present work, we studied how BAG3 controls autophagy in HeLa and HEK293 cells. Our results showed that BAG3 regulates the basal amount of total cellular LC3B protein by controlling its mRNA translation. This effect was apparently specific to LC3B because other ATG protein levels were not affected. BAG3 knockdown did not affect LC3B lipidation induced by nutrient deprivation or proteasome inhibition. We concluded that BAG3 maintains the basal amount of LC3B protein by controlling the translation of its mRNA in HeLa and HEK293 cells.     

Antimicrobial Combinations against Pan-Resistant Acinetobacter baumannii Isolates with Different Resistance Mechanisms

The study investigated the effect of antibiotic combinations against 20 clinical isolates of A. baumannii (seven colistin-resistant and 13 colistin-susceptible) with different resistance mechanisms. Clinical data, treatment, and patient mortality were evaluated. The following methods were used: MIC, PCRs, and outer membrane protein (OMP) analysis. Synergy was investigated using the checkerboard and time-kill methods. Clonality was evaluated by PFGE. Based on clonality, the whole genome sequence of six A. baumannii isolates was analyzed. All isolates were resistant to meropenem, rifampicin, and fosfomycin. OXA-23 and OXA-143 were the most frequent carbapenemases found. Four isolates showed loss of a 43kDa OMP_. The colistin-susceptible isolates belonged to different clones and showed the highest synergistic effect with fosfomycin-amikacin. Among colistin-resistant isolates, the highest synergistic effect was observed with the combinations of colistin-rifampicin followed by colistin-vancomycin. All colistin-resistant isolates harbored bla_OXA-23-like and belonged to CC113. Clinical and demographic data were available for 18 of 20 patients. Fourteen received treatment and eight patients died during treatment. The most frequent site of infection was the blood in 13 of 14 patients. Seven patients received vancomycin plus an active drug against A. baumannii; however, mortality did not differ in this group. The synergistic effect was similar for colistin-susceptible isolates of distinct clonal origin presenting with the same resistance mechanism. Overall mortality and death during treatment was high, and despite the high synergism in vitro with vancomycin, death did not differ comparing the use or not of vancomycin plus an active drug against A. baumannii.     

Assessing Disease and Mortality among Small Cetaceans Stranded at a World Heritage Site in Southern Brazil

Cetaceans are considered environmental sentinels and their health often reflects either anthropogenic or natural spatio-temporal disturbances. This study investigated the pathological findings and mortality of small cetaceans with the aim of detecting hazards and monitoring health trends in a high-biodiversity area. Between 2007 and 2012, 218 stranded cetaceans were recorded on the Paraná coast, southern Brazil. Fifty-seven (26.1%) of these animals, including 50 Sotalia guianensis, 2 Pontoporia blainvillei, 2 Stenella frontalis, 1 Stenella longirostris, 1 Tursiops truncatus and 1 Globicephala melas were necropsied and samples were collected for histopathology. Causes of death were determined in 46 of the 57 (80.7%) animals and most (30 or 65.2%) were ascribed to anthropogenic activities, including fisheries bycatch (28/30) and trauma (2/30). The remaining 16 fatalities were considered natural, and attributed to pneumonia (10/16), emaciation (3/16), septicemia (1/16), neonatal pathology (1/16) and choking via food obstruction (1/16). Irrespective of the cause, bronchointerstitial pneumonia, associated with parasitism, lymphadenitis and membranous glomerulonephritis were common findings among all fatalities. These results suggest, that while anthropogenic activities are a leading cause of cetacean strandings in Paraná, underlying pre-existing diseases may contribute towards deaths. Although the studied area is considered a biosphere reserve by UNESCO, complex anthropogenic and natural interactions might be occurring, increasing cetacean susceptibility to hazards. This study may help facilitate developing an effective conservation plan for coastal cetaceans focusing on reducing fisheries interactions, habitat degradation and pollution as mechanisms for ultimately increasing species resilience.     

Biogenic synthesis of silver nanoparticles using Brazilian propolis

Biological methods have been used to synthesize silver nanoparticles through materials such as bacteria, fungi, plants, and propolis due to their reducing properties, stabilizer role and environmentally friendly characteristic. Considering the antimicrobial activity of propolis as well as the broad-spectrum antibacterial effects of silver nanoparticles, this study aim to describe the use of Brazilian propolis to synthesize silver nanoparticles (AgNP-P) and investigate its antimicrobial activity. The synthesis was optimized by factorial design, choosing the best conditions for smaller size particles. AgNP-P demonstrated a maximum absorbance at 412 nm in ultraviolet-visible spectra, which indicated a spherical format and its formation. Dynamic light scattering demonstrated a hydrodynamic size of 109 nm and polydispersity index less than 0.3, showing a good size distribution and stability. After its purification via centrifugation, microscopy analysis corroborates the format and showed the presence of propolis around silver nanoparticle. X-ray diffraction peaks were attributed to the main planes of the metallic silver crystalline structure; meanwhile infrared spectroscopy demonstrated the main groups responsible for silver reduction, represented by ∼22% of AgNP-P indicates by thermal analysis. Our product revealed an important antimicrobial activity indicating a synergism between propolis and silver nanoparticles as expected and promising to be an effective antimicrobial product to be used in infections.     

Spontaneous meningoencephalitis by Staphylococcus aureus in an infant golden‐headed lion tamarin (Leontopithecus chrysomelas)

Non‐human primates are susceptible to many bacteria, some of which bear zoonotic potential. We report the pathologic features of spontaneous fulminating meningoencephalitis by Staphylococcus aureus in a captive infant golden‐headed lion tamarin (Leontopithecus chrysomelas) from Brazil.     

Identification of Biomarkers of Mercury Contamination in Brachyplatystoma filamentosum of the Madeira River,Brazil, Using Metalloproteomic Strategies

Biological Trace Element Research - Predator fish can accumulate high levels of mercury, which qualifies them as potential indicators of this toxic metal. The predatory species Brachyplatystoma...     

Frequency of Strongyloides stercoralis infection in alcoholics

Several studies have shown that chronic alcoholics have increased susceptibility to infections due to higher exposure to infectious agents as well as breakdown in their immune defenses. As Strongyloides stercoralis infection is usually more relevant in immunocompromised patients, the aim of this study was to evaluate the frequency of S. stercoralis infection in alcoholics. Thus, coproparasitological examination was carried out in 145 subjects, from which 45 were chronic alcoholics (mean age of 45.7 +/- 11.0 years), 10 were nonalcoholic cirrhotic patients (mean age of 50.2 +/- 13.1 years), and 90 were asymptomatic nonalcoholic subjects (mean age of 46.7 +/- 10.1 years), which served as controls. From the alcoholics, 9 had hepatic cirrhosis, 9 had chronic pancreatitis and 27 had neither cirrhosis nor pancreatitis. For the diagnosis of strongyloidiasis, the Baermann-Moraes and Lutz methods were used in three fecal samples from each subject. Samples were collected at alternated days, and three slides of each sample were analyzed for each method, thus totalizing 2,610 slides examined. The frequency of strongloidiasis in the total alcoholic group (33.3%) and in the subgroups of alcoholics, i.e., patients with hepatic cirrhosis (44.4%), with chronic pancreatitis (33.3%), and those with no cirrhosis or pancreatitis (29.6%) was statistically higher than that found in the control group (5.5%). None of the individuals with nonalcoholic hepatic cirrhosis had S. stercoralis infection. Our results showed that the chronic alcoholism itself is an important factor that predisposes to strongyloidiasis.