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Emerging infectious diseases have contributed to the decline in amphibian species around the world. Among them, ranavirus infections have major importance, as they significantly impact biodiversity and frog rearing. This study aims to conduct an integrative review of the recent literature, including epidemiological data on the distribution, prevalence, and circulating species and strains, to identify gaps that may still exist and suggest potential directions for future research. We synthesized data collected from 68 articles found in two scientific databases (Scopus and PubMed), and we provide a situational update on ranavirus infections in anurans. We found relevant reports confirming the high prevalence of this pathogen and the risk it poses, including to endangered species. However, there is still information to be clarified regarding its distribution in different territories and the identification of the species involved in infections. [ABSTRACT FROM AUTHOR]

Background: Canine distemper (CD) is a worldwide spread disease that has been described in 12 families of mammals, especially in the Carnivora order, being better studied in domestic canines where vaccination represents the best means of control. CD is controlled by vaccination, but many cases of the disease still occur in vaccinated animals. Aim: The aim of this work was to study antigen-specific epitopes that can subsidize the development of a new vaccine approach. Methods: Mapping of T cell reactive epitopes for CD virus (CDV) was carried out through enzyme-linked immunospot assays using 119 overlapped synthetic peptides from the viral hemagglutinin protein, grouped in 22 pools forming a matrix to test the immune response of 32 animals. Results: Evaluations using the criteria established to identify reactive pools, demonstrated that 26 animals presented at least one reactive pool, that one pool was not reactive to any animal, and six pools were the most frequent among the reactive peptides. The crisscrossing of the most reactive pools in the matrix revealed nine peptides considered potential candidate epitopes for T cell stimulation against the CDV and those were used to design an in-silico protein, containing also predicted epitopes for B cell stimulation, and further analyzed using immune epitope databases to ensure protein quality and stability. Conclusion: The final in silico optimized protein presents characteristics that qualify it to be used to develop a new prototype epitope-based anti-CDV vaccine. [ABSTRACT FROM AUTHOR]

Abstract: Nordihydroguaiaretic acid (NDGA) is a plant lignan produced by Larrea tridentata, the creosote bush of the American southwest. In this report we examine the mechanism underlying the ability of NDGA to inhibit TNF-induced apoptosis. Our results show that NDGA blocks many key indicators of apoptosis. Caspase cleavage, mitochondrial inactivation, externalization of phosphatidyl serine, and 51Cr-release were all blocked by low micromolar concentrations of NDGA. NDGA also inhibited the cPLA2-dependent release of 3H-arachidonic acid. We investigated this activity and found that NDGA prevented the rise in intracellular calcium necessary for the apoptotic activation of cPLA2. On the other hand, NDGA did not interfere with the TNF-induced phosphorylation of cPLA2, indicating that NDGA does not block all TNF-dependent signaling. Finally, we asked whether the anti-apoptotic effect of NDGA could be attributed to its anti-oxidant activity. Comparison with the effects of butylated hydroxyanisole (BHA) did not completely support this hypothesis. While BHA strongly inhibited caspase activation and partially blocked the release of 51Cr, it was unable to significantly block the calcium response or the release of 3H-arachidonic acid associated with TNF-induced apoptosis. The anti-oxidant activity of NDGA may, therefore, explain some but not all of its anti-apoptotic activity. [Copyright &y& Elsevier]

Abstract: Low concentrations of HgCl2 elicited, in Saccharomyces cerevisiae, a transitory increase in the ATP level followed by a decrease of its concentration, until almost disappearance. At 1μM HgCl2, the increase in ATP lasted for about 30min, while at 10μM the increase was only observed in the first 5min of treatment. The initial burst of ATP was accompanied by a decrease in the level of hexose phosphates, whereas during the decrease of ATP an increase in the inosine and hexose phosphates levels took place. The treatment with HgCl2 inhibited the plasma membrane proton ATPase but not the activities of hexokinase or 6-phosphofructokinase. [Copyright &y& Elsevier]

Abstract: Saccharomyces cerevisiae cells (strain W303) grown in a minimal medium (containing 2% or 0.1% glucose) until exponential or stationary phase, were subjected to chronological aging in water, and yeast viability and nucleotide content were analyzed along several days of nutrient starvation. Cells collected in exponential phase (whether grown in the presence of 0.1% or 2% glucose) were viable up to five days and thereafter the viability decreased linearly with a half-survival rate of around eight days. ATP and other nucleoside triphosphates decreased similarly in both cases. Cells collected in stationary phase, and transferred to water, behaved differently whether grown in 0.1% or in 2% glucose, with a half-survival life of around nine and 28 days respectively. A double mutant in glycogen synthase (gsy1Δ gsy2Δ) and its isogenic wild-type strain, grown to stationary phase in 2% glucose, presented a similar half-survival life of around eight days. The W303 cells grown to stationary phase in the presence of 2% glucose showed a 7-fold increase of UDP-N-acetylglucosamine (UDP-GlcNAc) as compared with the level present in the cells grown in any of the other three metabolic situations. The nature of UDP-GlcNAc was established by MALDI-TOF ionization analysis. It is also worth noting that the rate of decay of NAD+ was lower than that of ATP in any of the situations here considered. [Copyright &y& Elsevier]

Background and Aim: Despite worldwide case reports, including Brazilian cases, no frequency study on infection of pets by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been conducted to date in Brazil. Accordingly, the present study was aimed to assess dogs and cats belonging to positive owners in Recife, Northeastern Brazil. Materials and Methods: This was a longitudinal prospective study on dogs and cats in the city of Recife whose owners were in isolation at home due to a confirmed laboratory diagnosis of SARS-CoV-2 through reverse-transcriptase polymerase chain reaction (RT-qPCR). Oral and rectal swabs from the pets were tested for the presence of SARS-CoV-2-specific RNA by means of RT-qPCR. Results: Among the pets tested, 0/16 dogs and 2/15 cats were positive for SARS-CoV-2. Interestingly, the two positive cats were owned by two unrelated asymptomatic veterinary students, which, therefore, post a warning to veterinarians worldwide. Conclusion: The findings herein indicate that cats may act as sentinels for human cases, particularly sharing households with asymptomatic human cases. Although with small sampling and convenient recruiting, the presence of infected cats by SARS-CoV-2 was most likely due to close cat-human contact with positive owners, posting a human-animal health threat when pets share the same bed and interact with owners without protection, particularly during owner self-isolation. Thus, infected owners should follow the same human preventive guidelines with their pets to avoid spreading infection. [ABSTRACT FROM AUTHOR]

Background and Aim: The emerging concerns regarding the new Coronavirus's ability to cause infection in pets has led to animal testing and worrisome findings reported all over the world in domesticated and wild animals. This study aimed to investigate severe acute respiratory syndrome coronavirus (SARS-CoV)-2 by quantitative reverse transcription-polymerase chain reaction in dog and cat samples with the clinical presentation for respiratory or gastrointestinal disease in Brazil. Materials and Methods: One hundred and twenty-five samples were collected from 12 states of Brazil that originated from the gastrointestinal, upper respiratory tract, and other sites, including some pools of samples from before the onset of the pandemic including blood and/or urine samples. They were tested for RT-PCR detection of respiratory or gastrointestinal pathogens through Respiratory or Diarrhea RT-PCR Panels in the  TECSA (Tecnologia em Saninade Animal - Animal Health Technology) Veterinary Medicine Laboratory. This work was conducted in compliance with ethical standards. Results: Seven different microorganisms that can cause respiratory and/or gastrointestinal clinical signs were detected in cats (Feline Coronavirus [FCoV], Feline Parvovirus, Feline Leukemia Virus, Feline Calicivirus, Mycoplasma felis, Campylobacter spp., and Cryptosporidium spp.) and three in dogs (canine distemper virus, Cryptosporidium spp., and Babesia spp.). Conclusion: Although the samples corresponded to the beginning of coronavirus disease-19 spread in Brazil and clinically correlated with the expected viral replication sites, none of the animals tested positive for SARS-CoV-2; reassuringly, four cats tested positive or FCoV none of them were positive for SARS-CoV2. The epidemiological surveillance of SARSCoV-2 in pets is considered a one health issue, important for monitoring the disease evolution, spread and minimizing the animal-human health impacts, and directing Public Health Policies. [ABSTRACT FROM AUTHOR]

Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. Author Summary: DNA and other nucleic acid vaccine technologies are advancing quickly, and new potent delivery methods are demonstrating great potential in human clinical trials. In this manuscript, we report a highly protective DNA vaccine against the yellow fever virus. This vaccine was engineered with a molecular adjuvant technology to enhance the exposure of the vaccine antigens to the immune system, resulting in augmented CD4+ helper responses. We postulate that the robust CD4+ responses help the B cells and the CD8+ cells mature more efficiently and produce better antibodies and cytotoxic cells, respectively. Our results show that vaccination with this yellow fever DNA formulation elicited protective levels of neutralizing antibodies and very strong cellular responses at similar levels to the responses elicited by the live attenuated 17DD vaccine. In addition, these results also suggest a very important role for cellular responses in mediating protection against yellow fever virus. The results reported here are very promising and further studies may lead to a new yellow fever vaccine for human use. [ABSTRACT FROM AUTHOR]

Attenuated yellow fever (YF) virus 17D/17DD vaccines are the only available protection from YF infection, which remains a significant source of morbidity and mortality in the tropical areas of the world. The attenuated YF virus vaccine, which is used worldwide, generates both long-lasting neutralizing antibodies and strong T-cell responses. However, on rare occasions, this vaccine has toxic side effects that can be fatal. This study presents the design of two non-viral DNA-based antigen formulations and the characterization of their expression and immunological properties. The two antigen formulations consist of DNA encoding the full-length envelope protein (p/YFE) or the full-length envelope protein fused to the lysosomal-associated membrane protein signal, LAMP-1 (pL/YFE), aimed at diverting antigen processing/presentation through the major histocompatibility complex II precursor compartments. The immune responses triggered by these formulations were evaluated in H2b and H2d backgrounds, corresponding to the C57Bl/6 and BALB/c mice strains, respectively. Both DNA constructs were able to induce very strong T-cell responses of similar magnitude against almost all epitopes that are also generated by the YF 17DD vaccine. The pL/YFE formulation performed best overall. In addition to the T-cell response, it was also able to stimulate high titers of anti-YF neutralizing antibodies comparable to the levels elicited by the 17DD vaccine. More importantly, the pL/YFE vaccine conferred 100% protection against the YF virus in intracerebrally challenged mice. These results indicate that pL/YFE DNA is an excellent vaccine candidate and should be considered for further developmental studies. [ABSTRACT FROM AUTHOR]

Highlights: [•] A recombinant capsid protein (rp26) of Equine Infectious Anemia Virus was expressed in Pichia pastoris. [•] The rp26 was evaluated in an enzyme-linked immunosorbent assay (ELISA) and agar gel immunodiffusion (AGID) test. [•] EIAV rp26 protein was identified by OIE standard polyclonal antibody anti EIAV. [•] This is the first report of EIAV p26 protein production in yeast cells. [Copyright &y& Elsevier]

The aim of the present work was to study the cadmium effects on growth, ultrastructure and polyphosphate metabolism, as well as to evaluate the metal removal and accumulation by Cunninghamella elegans (IFM 46109) growing in culture medium. The presence of cadmium reduced growth, and a longer lag phase was observed. However, the phosphate uptake from the culture medium increased 15% when compared to the control. Moreover, C. elegans removed 70%-81% of the cadmium added to the culture medium during its growth. The C. elegans mycelia showed a removal efficiency of 280 mg/g at a cadmium concentration of 22.10 mg/L, and the removal velocity of cadmium was 0.107 mg/h. Additionally, it was observed that cadmium induced vacuolization, the presence of electron dense deposits in vacuoles, cytoplasm and cell membranes, as well as the distinct behavior of polyphosphate fractions. The results obtained with C. elegans suggest that precipitation, vacuolization and polyphosphate fractions were associated to cadmium tolerance, and this species demonstrated a higher potential for bioremediation of heavy metals. [ABSTRACT FROM AUTHOR]