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Background The rapid spread and increase of chikungunya (CHIKV) and dengue (DENV) cases in Brazilian regions in 2023 has raised concerns about the impact of arboviruses on public health. Epidemiological and genomic surveillance was performed to estimate the introduction and spread of CHIKV and DENV in Brazil. Methods This study obtained results from the Hermes Pardini (HP), a private medical laboratory, and the Health Department of Minas Gerais state (SES-MG). We investigated the positivity rates of CHIKV and DENV by analyzing the results of 139,457 samples tested for CHIKV (44,029 in 2022 and 95,428 in 2023) and 491,528 samples tested for DENV (163,674 in 2022 and 327,854 in 2023) across the five representative geographical regions of Brazil. Genome sequencing was performed on 80 CHIKV and 153 DENV samples that had been positive for RT-PCR tests. Results In our sampling, the data from CHIKV tests indicated that the Northeast region had the highest regional positivity rate in 2022 (58.1%). However, in 2023, the Southeast region recorded the highest positivity rate (40.5%). With regard to DENV, the South region exhibited the highest regional positivity rate in both 2022 (40.8%) and 2023 (22.7%), followed by the Southeast region in both years (34.8% in 2022; 21.4% in 2023). During the first 30 epidemiological weeks of 2023 in the state of Minas Gerais (MG), there was a 5.8-fold increase in CHIKV cases and a 3.5-fold increase in DENV compared to the same period in 2022. Analysis of 151 new DENV-1 and 80 CHIKV genomes revealed the presence of three main clusters of CHIKV and circulation of several DENV lineages in MG. All CHIKV clades are closely related to genomes from previous Brazilian outbreaks in the Northeast, suggesting importation events from this region to MG. We detected the RNA of both viruses in approximately 12.75% of the confirmed positive cases, suggesting an increase of co-infection with DENV and CHIKV during the period of analysis. Conclusions These high rates of re-emergence and co-infection with both arboviruses provide useful data for implementing control measures of Aedes vectors and the urgent implementation of public health politics to reduce the numbers of CHIKV and DENV cases in the country.

Background The pandemic caused by SARS-CoV-2 has not only affected humans but also raised concerns about its transmission to wild animals, potentially creating natural reservoirs. Understanding these dynamics is critical for preventing future pandemics and developing control strategies. This study aims to investigate the presence of SARS-CoV-2 in wild mammals at the Belo Horizonte Zoo in Brazil, analyzing the virus's evolution and zoonotic potential. Methods The study was conducted at the Belo Horizonte Zoo, Minas Gerais, Brazil, covering a diverse population of mammals. Oropharyngeal, rectal, and nasal swabs were collected from 47 captive animals between November 2021 and March 2023. SARS-CoV-2 presence was determined using RT-PCR, and positive samples were sequenced for phylogenetic analysis. Consensus genomes were classified using Pangolin and NextClade tools, and a maximum likelihood phylogeny was inferred using IQ-Tree. Results Of the 47 animals tested, nine (19.1%) were positive for SARS-CoV-2. Positive samples included rectal, oropharyngeal, and nasal swabs, with the highest positivity in rectal samples. Three genomes were successfully sequenced, revealing two variants: VOC Alpha in a maned wolf ( Chrysocyon brachyurus ) and a fallow deer ( Dama dama ), and VOC Omicron in a western lowland gorilla ( Gorilla gorilla gorilla ). Phylogenetic analysis indicated potential human-to-animal transmission, with animal genomes clustering close to human samples from the same region. Conclusions This study highlights the presence of SARS-CoV-2 in various wild mammal species at the Belo Horizonte Zoo, emphasizing the virus's zoonotic potential and the complexity of interspecies transmission. The detection of different variants suggests ongoing viral evolution and adaptation in new hosts. Continuous monitoring and genomic surveillance of SARS-CoV-2 in wildlife are essential for understanding its transmission dynamics and preventing future zoonotic outbreaks. These findings underscore the need for integrated public health strategies that include wildlife monitoring to mitigate the risks posed by emerging infectious diseases.

The Plant Vigor Hypothesis (PVH) predicts that herbivorous insects will preferentially feed on large plants with more vigorous growth, or on more vigorous parts of the plant. However, we still need to understand how these predictions work throughout the ontogenic stages of plants and with other groups of natural plant enemies. We tested the PVH using gall-inducing insects, free-living herbivorous insects, and pathogenic fungi associated with Hymenaea courbaril seedlings of the same age cohort (six months) from seeds germinated in greenhouses. We classified the plants into three different sizes: small, medium, and large seedlings, and then measured above and belowground biomass, plant height, leaf area, and leaf area consumed by free-living herbivores. We also measured nutrient partitioning among roots, stems, and leaves and estimated hypersensitive responses. We found no differences in leaf area consumed by free-living herbivorous insects between plant size groups. However, we observed that larger seedlings were more vigorous and had greater nutritional value and, thus, represented adequate niches for colonization by pathogens and gall-inducing insects, confirming the PVH for both groups. The hypersensitive response was greater in medium and large seedlings, proving to be an effective defense mechanism against gall-inducing insects. Therefore, we highlight that nutritional quality, plant vigor and hypersensitivity response are factors that influence the incidence of pathogens and galling insects on H. courbaril seedlings.

PDE4B (phosphodiesterase‐4B) has an important role in cancer and in pharmacology of some disorders, such as inflammatory diseases. Remarkably in Native Americans, PDE4B variants are associated with acute lymphoblastic leukemia (ALL) relapse, as this gene modulates sensitivity of glucocorticoids used in ALL chemotherapy. PDE4B allele rs6683977.G, associated with genomic regions of Native American origin in US‐Hispanics (admixed among Native Americans, Europeans, and Africans), increases ALL relapse risk, contributing to an association between Native American ancestry and ALL relapse that disappeared with an extra‐phase of chemotherapy. This result insinuates that indigenous populations along the Americas may have high frequencies of rs6683977.G, but this has never been corroborated. We studied ancestry and PDE4B diversity in 951 healthy individuals from nine Latin American populations. In non‐admixed Native American populations rs6683977.G has frequencies greater than 90%, is in linkage disequilibrium with other ALL relapse associated and regulatory variants in PDE4B‐intron‐7, conforming haplotypes showing their highest worldwide frequencies in Native Americans (>0.82). Our findings inform the discussion on the pertinence of an extra‐phase of chemotherapy in Native American populations, and exemplifies how knowledge generated in US‐Hispanics is relevant for their even more neglected and vulnerable Native American ancestors along the American continent.

Brazil is one of the countries most affected by COVID-19, with the highest number of deaths recorded. Brazilian Health Institutions have reported four main peaks of positive COVID-19 cases. The last two waves were characterized by the emergence of the VOC Omicron and its sublineages. This study aimed to conduct a retrospective surveillance study illustrating the emergence, dissemination, and diversification of the VOC Omicron in 15 regional health units (RHUs) in MG, the second most populous state in Brazil, by combining epidemiological and genomic data. A total of 5643 confirmed positive COVID-19 samples were genotyped using the panels TaqMan SARS-CoV-2 Mutation and 4Plex SC2/VOC Bio-Manguinhos to define mutations classifying the BA.1, BA.2, BA.4, and BA.5 sublineages. While sublineages BA.1 and BA.2 were more prevalent during the third wave, BA.4 and BA.5 dominated the fourth wave in the state. Epidemiological and viral genome data suggest that age and vaccination with booster doses were the main factors related to clinical outcomes, reducing the number of deaths, irrespective of the Omicron sublineages. Complete genome sequencing of 253 positive samples confirmed the circulation of the BA.1, BA.2, BA.4, and BA.5 subvariants, and phylogenomic analysis demonstrated that the VOC Omicron was introduced through multiple international events, followed by transmission within the state of MG. In addition to the four subvariants, other lineages have been identified at low frequency, including BQ.1.1 and XAG. This integrative study reinforces that the evolution of Omicron sublineages was the most significant factor driving the highest peaks of positive COVID-19 cases without an increase in more severe cases, prevented by vaccination boosters.

Located in the southeast of Brazil, the Rio Santo Antônio basin, a tributary of the Rio Doce basin, has many preserved remnants of the Atlantic Forest, but is otherwise under imminent threats from several land use stressors. In this study, we used environmental DNA (eDNA) metabarcoding to assess vertebrate diversity in the headwaters of the Rio Santo Antônio basin, aiming to elucidate key ecological factors influencing its vertebrate richness. Additionally, we provide the first vertebrate species inventory for the basin. In 2023, water samples from 15 third‐ and fourth‐order streams were collected and metabarcoding assays targeting the mitochondrial 12S rRNA gene were employed to detect the vertebrate community. We identified 119 vertebrate taxonomic units distributed across two distinct communities: one on the eastern slope and another on the western slope of the basin, both influenced by large‐scale mining activities. We demonstrated that vertebrate richness was not correlated with forest cover or pH but was strongly associated with the water's oxidation–reduction potential (ORP). We interpret ORP as a reflection of local conditions, where sites with higher ORP values also exhibited greater taxonomic richness and were related to greater forest cover, lower air and water temperatures, and greater distance from mining activity. The vertebrate biodiversity and biogeographic distribution described here highlight the value of eDNA metabarcoding as a monitoring approach and support decision‐making and conservation efforts aimed at preserving the remaining Atlantic Forest in the headwaters of the Rio Santo Antônio basin.

AimsTo identify calcifying epithelial odontogenic tumour (CEOT) mutations in oncogenes and tumour suppressor genes.MethodsA panel of 50 genes commonly mutated in cancer was sequenced in CEOT by next-generation sequencing. Sanger sequencing was used to cover the region of the frameshift deletion identified in one sample.ResultsMissense single nucleotide variants (SNVs) with minor allele frequency (MAF) <1% were detected in PTEN, MET and JAK3. A frameshift deletion in CDKN2A occurred in association with a missense mutation in the same gene region, suggesting a second hit in the inactivation of this gene. APC, KDR, KIT, PIK3CA and TP53 missense SNVs were identified; however, these are common SNVs, showing MAF >1%.ConclusionCEOT harbours mutations in the tumour suppressor PTEN and CDKN2A and in the oncogenes JAK3 and MET. As these mutations occurred in only one case each, they are probably not driver mutations for these tumours.

Since its first identification in Brazil, the variant of concern (VOC) Gamma has been associated with increased infection and transmission rates, hospitalizations, and deaths. Minas Gerais (MG), the second-largest populated Brazilian state with more than 20 million inhabitants, observed a peak of cases and deaths in March–April 2021. We conducted a surveillance study in 1240 COVID-19-positive samples from 305 municipalities distributed across MG’s 28 Regional Health Units (RHU) between 1 March to 27 April 2021. The most common variant was the VOC Gamma (71.2%), followed by the variant of interest (VOI) zeta (12.4%) and VOC alpha (9.6%). Although the predominance of Gamma was found in most of the RHUs, clusters of Zeta and Alpha variants were observed. One Alpha-clustered RHU has a history of high human mobility from countries with Alpha predominance. Other less frequent lineages, such as P.4, P.5, and P.7, were also identified. With our genomic characterization approach, we estimated the introduction of Gamma on 7 January 2021, at RHU Belo Horizonte. Differences in mortality between the Zeta, Gamma and Alpha variants were not observed. We reinforce the importance of vaccination programs to prevent severe cases and deaths during transmission peaks.

ATM inactivation and consequent defective DNA repair signalling may lead to accumulation of DNA damage and the emergence of mutations, increasing the risk of neoplasms development8 as shown in schematic (figure 2). [...]to test the possible functional effect of the missense ATM mutation detected, we assessed in our samples the immunohistochemical expression of two substrates of its pathway (phospho-Chk2 and phospho-histone H2A.X). DNA damage might be caused by endogenous and/or exogenous agents and promotes cellular responses that can arrest cell cycle progression, DNA repair and apoptosis. [...]only two of six samples showed mutations in the oncogenes and tumour suppressor genes screened, but none occurred in PTPN11 and PTEN genes.

The coronavirus disease 2019 (COVID-19) pandemic had quite an impact on dental health care. Concerns about the risk of SARS-CoV-2 transmission through contaminant fluids and droplet formation during several dental procedures highly impacted dental health care, drastically reducing the number of dental practices worldwide. To monitor SARS-CoV-2 contamination in dental clinics, a longitudinal study was carried out during the return of dental practice at university. Dental health care professionals [(DHCPs); teachers, undergraduate dental students, and dental assistants] and patients were screened for SARS-CoV-2 RNA in a dental school clinic environment from 11 January to 12 March 2021 (9 weeks). Serological testing was performed on DHCPs in two-time points. Additionally, samples with low values were sequenced to identify the circulating SARS-CoV-2 variant and possible transmission clusters. We found a low number of dental staff (5.8%), patients (0.9%), and environment sites (0.8%) positive for SARS-CoV-2. Most positive cases had asymptomatic to mild symptoms, and two asymptomatic DHCPs presented prolonged infection. In the first week after previous exposure to COVID-19, 16.2% of DHCPs had IgM or IgG antibodies against SARS-CoV-2, and 1/3 of them had undetected antibodies in the last weeks. The variant zeta (P.2) could be detected. No cross-infection was observed between participants. Our study suggests that dental practice can be safely executed when adequate control measures and biosafety protocols are applied. DHCP and patient testing, patient telemonitoring, proper use of personal protection equipment, and sanitization of surfaces are essential to avoid SARS-CoV-2 cross-infection in dental practice.