A decade-long journey shed light on chemical composition and field determination of acid mine drainage in Brazil.

Regular monitoring of Acid Mine Drainage (AMD) is essential for understanding its extent and impact on water resources. Traditional manual sampling methods have limitations, such as limited representativeness and delayed lab analysis. High-frequency monitoring offers an alternative, enabling real-time analysis of AMD fluctuations and determination of constituents in the field. This study assessed a decade-long environmental monitoring database from watersheds impacted by coal mining in Brazil to analyze the relationships between physical properties and constituents from different water sources affected by AMD. Samples were grouped into four categories based on location and contamination levels. Results revealed that water samples from the two groups not affected by AMD exhibited near-neutral pH, low metal and sulfate concentrations, and a large portion of samples below the quantification limit for Mn and Al. In contrast, samples from groups affected by AMD displayed high metal and sulfate concentrations and acidic pH, with the highest contamination observed in the underground mine discharges group (AMD UMD). Spearman correlation analyzes between field (pH and electrical conductivity (EC)) and lab (SO42-, Fe, Mn, and Al) parameters showed no significant correlations in non-AMD-affected groups, but significant correlations in AMD-affected groups, particularly the Streams group. A regression model between sulfate and EC was identified as the best predictor for AMD, enabling continuous, low-cost monitoring of contaminated streams and providing insight into previously unobserved AMD processes, such as variations in contamination during storm events and river flushing.

Analysis of thermal discomfort associated with synoptic conditions in the city of Pelotas, southernmost region of Brazil.

Here, we evaluated the influence of outdoor environmental conditions (synoptic weather conditions) on human thermal discomfort in the five macro-regions of Pelotas city, located in the southernmost region of Brazil. To do this, meteorological sensors (HOBO MX2301A) were installed outside the residences to measure the air temperature, dew point temperature, and relative humidity between 18 January and 20 August 2019. Two well-established simplified biometeorological indices were examined seasonally: (i) humidex for the summer months and (ii) effective temperature as a function of wind for the autumn and winter months. Our findings showed seasonal differences related to human thermal discomfort and outdoor environmental conditions. The thermal discomfort was highest in the afternoons during the summer months and at night during the winter months. The seasonal variation in human thermal discomfort was highly associated with the meteorological conditions. In summer, the presence of the South Atlantic Subtropical Anticyclone (SASA) contributed to heat stress. The SASA combined with the continent's low humidity contributed to the perceived sensation of thermal discomfort. In the winter, thermal discomfort was associated with the decrease in air humidity caused by high atmospheric pressure systems, which led to a decrease in both air temperature and air moisture content. Our findings suggest that a better understanding of the complex interplay between outdoor environmental factors and human thermal comfort is needed in order to mitigate the negative effects of thermal discomfort.

DENV-1 genotype V linked to the 2022 dengue epidemic in Southern Brazil.

Even though Brazil is a country where the dengue virus (DENV) is endemic, until recently, Southern states did not have significant viral circulation, such as Rio Grande do Sul (RS), and some municipalities were even considered dengue-free. During 2022, these places have shown a sharp increase in the incidence of the disease, apparently following a worldwide growth pattern. Therefore, in this study, we monitor and characterize the genetic diversity of DENV circulating in southern Brazil through next-generation sequencing during an outbreak in 2022. We generated 70 DENV-1 genome sequences, all characterized as genotype V, divided into two clade clusters in the L1 lineage. Furthermore, unique mutations have been described in each clade of L1 lineage. Our results are essential in managing outbreaks since these data provide important information during the emergence of DENV circulation in RS. Since the south of Brazil has a lower viral circulation when compared to other Brazilian states, RS still lacks data that can help in understanding the transmission, dissemination, and evolution of the dengue virus. Hence, genomic surveillance efforts are essential to increase the accuracy of preventive actions and to control viral dissemination.

Evaluation of biometry and blood concentration of heavy metals in free-living Chelonia mydas with and without fibropapillomatosis in southern Brazil.

The present study determined the presence of heavy metals in green sea turtles with and without fibropapillomatosis in Itapirubá and Cassino beaches, southern Brazil. The weight, curved length of the carapace and body index were determined and blood was collected to quantify the concentrations of cadmium, lead and mercury. A total of 51 blood samples were analyzed, being 46 positives for at least one of the metals. There was a greater number of juvenile turtles in Itapirubá, larger in size and weight than those in Cassino. No statistical differences were found between metal concentrations between regions or between turtles with and without fibropapillomatosis. There was no significant correlation between metal concentrations, biometric variables and the presence of fibropapilomatose. Metal concentrations were low in both regions, with the highest concentrations being Cd and the lowest Hg.

Risk assessment validation in patients with pulmonary arterial hypertension: Data from a Southern Brazil registry (RESPHIRAR study).

Pulmonary arterial hypertension (PAH) is a severe and progressive disease characterized by increased pulmonary vascular resistance, ultimately leading to right heart failure and death. Registries are a valuable tool in the research of rare conditions such as PAH. Moreover, the risk assessment strategy has been validated in European and North American registries and has been reported to provide an accurate prediction of mortality and the clinical advantage of reaching low-risk status. However, there is no available data from Brazil. Thus, the aim of the present study was to describe the characteristics of a sample of PAH from Southern Brazil and to retrospectively validate the risk assessment at our population. The RESPHIRAR is a retrospective and multicentric registry on pulmonary hypertension. With a join collaboration from nine centers in Southern Brazil, demographics, clinical presentation, and hemodynamics data of PAH were collected between 2007 and 2017. Moreover, the REVEAL 2.0 and REVEAL 2.0 Lite risk assessments were validated in our population. Overall, 370 PAH patients were included in the present study. Patients were predominantly female (78.5%) and had a mean age of 41.8 ± 18.8 years. Most patients (33.4%) had idiopathic PAH, 30.2% had PAH associated with congenital heart disease, and 23.5% had PAH associated with connective tissue disease. The low-risk group showed significantly lower mortality than the intermediated- or high-risk group at diagnosis (p < 0.05). In conclusion, our data suggest that REVEAL 2.0 and REVEAL 2.0 Lite risk assessments can predict mortality risk in PAH patients in Southern Brazil.

Traditional Plants Used in Southern Brazil as a Source to Wound Healing Therapies.

In southern Brazil, the biodiversity is great and the traditional use of medicinal plants for wound healing has been documented in ethnobotanical studies and pharmacological studies have assessed their wound properties and phytochemistry. Therefore, this study evaluated ethnobotanical surveys regarding medicinal plants used in southern Brazil for wound healing and studies about the healing properties of these plants published between 2000 and 2022. To retrieve articles related to the study, Web of Science, PubMed (NLM), Open Access Journals, Scielo, Lilacs, and Google Scholar, with keywords including medicinal plants, wound healing, and South of Brazil, have been used. As a result, 73 medicinal plants belonging to 39 families were found in ethnobotanical surveys as a traditional resource used for wound healing in southern Brazil, 15 of which were cited more than once. Besides, 14 of these 15 plants were also used as healing agents worldwide. The most cited plant with healing actions in southern Brazil was Symphytum officinale L. (comfrey). From 2000 to date, 44 articles scientifically demonstrated the wound-healing effects of the southern Brazilian plants found in ethnobotanical surveys reviewed. The folk medicine of southern Brazil presents a variety of medicinal plants for wound-healing purposes, and scientific data were found for some of those plants. However, the wound-healing properties of many plants have yet to be investigated, and the current literature still needs more phytochemical information about the plants studied. Aside from this, the future focus should be on the standardization of herbal extracts, and further research is required to investigate the pharmacological mechanisms. Clinical research in this area remains in its infancy and warrants more robust further clinical studies.

Prevalence and risk factors associated with Babesia bovis infection in Crioula Lageana cattle.

INTRODUCTION: Bovine babesiosis caused by the protozoan Babesia bovis is a worldwide disease and causes great economic damage to livestock. There are no studies on the epidemiology of this disease in native breeds such as Crioula Lageana cattle raised in the South of Brazil. METHODOLOGY: DNA samples from 311 animals were amplified by polymerase chain reaction (PCR) for the identification of the gene rap-1 (Rhoptry Associated Protein 1) from B. bovis. An epidemiological questionnaire was used to determine the risk factors associated with infection. RESULTS: The prevalence of B. bovis infection was 72% (224/311). Age and tick infestation affected infection. The factors associated with infection were the breeding objective (p = 0.042; CI = 0.746-0.995; OR = 0.861), contact of cattle with other animal species (p = 0.002; CI = 0.517-0.860; OR = 0.484), absence of tick control (p = < 0.001; CI = 0.074-0.480; OR = 0.188) and timing of tick treatment (p = 0.026; CI = 0.673-0.975; OR = 0.810), and these were considered to be factors that can protect against the disease. CONCLUSIONS: The Crioula Lageana cattle breed has near enzootic stability with regards to B. bovis infection.

Hospital mortality rates between 2015 and 2022: a comparison between the pre-pandemic and pandemic period shows that COVID-19 is a critical health problem

Introduction: COVID-19 caused 6.2 million deaths in the world. The present study aims to evaluate hospital mortality rates from 2015 to 2022, to compare the pre and during the pandemic period.Methods: The study was carried out in a private hospital in southern Brazil. 174,013 hospital discharges between January 2015 and March 2022 were analyzed. Pearson's chi-squared test was performed to evaluate the mortality rate by year. Differences between mortality rates before and during the pandemic was tested with Student's t-test. P-values < 0.05 for all tests were considered significant.Results: Mortality rates were 2.29% in 2015; 2.37% in 2016; 2.25% in 2017; 2.31% in 2018; 2.46% in 2019; 3.45% in 2020; 3.58% in 2021 and 2.77% in 2022 (p< 0.01). The mortality for 2020 and 2021 was higher than in the other years (3.50% ± 0.14 vs 2.34% ± 0.05; p < 0.01).Conclusion: The mortality rates were significantly higher in the years 2020 and 2021, demonstrating that COVID-19 is a critical health problem.

Viral isolation allows characterization of early samples of SARS-CoV-2 lineage B1.1.33 with unique mutations (S: H655Y and T63N) circulating in Southern Brazil in 2020.

Different approaches are in use to improve our knowledge about the causative agent of coronavirus disease (COVID-19). Cell culture-based methods are the better way to perform viral isolation, evaluate viral infectivity, and amplify the virus. Furthermore, next-generation sequencing (NGS) have been essential to analyze a complete genome and to describe new viral species and lineages that have arisen over time. Four naso-oropharyngeal swab samples, collected from April to July of 2020, were isolated and sequenced aiming to produce viral stocks and analyze the mutational profile of the found lineage. B.1.1.33 was the lineage detected in all sequences. Although the samples belong to the same lineage, it was possible to evaluate different mutations found including some that were first described in these sequences, like the S:H655Y and T63N. The results described here can help to elicit how the pandemic started to spread and how it has been evolving in south Brazil.

Cumulative potential and half-life of [imazapic + imazapyr] in lowland soils of Rio Grande Do Sul grown with clearfield® rice.

The objectives of this study were to estimate the residual and half-life of [imazapic + imazapyr] and to infer on the impact of these residuals over time. The first experiment comprised the application of [imazapic + imazapyr] to Clearfield® rice. On the following summer cropping season (365 days later), undeformed soil samples 0-5 cm depth were collected and seeds of six species or varieties were sown as bioindicators of residuals (experiment 2), being assessed plant height and dry mass 20 days after emergence start. The third experiment comprised the cultivation of the same species submitted to ten increasing herbicide doses (0-280 g ha-1) to establish standard response curves, also assessing plant height and dry mass 20 days after emergence start. About 2.1-5.8% of the applied imazapic remains in soil after one year, for the label doses. Imazapyr was considered to be at negligible doses as its half-life is short, and less than 0.0000001% of the applied dose is expected to be in soil 365 days later. The expected imazapic half-life in lowland areas of Southern Brazil is longer than for dryland, being estimated as between 63 and 77 days (95% confidence interval), contrasting to the 60 days half-life previously estimated for dryland soils.

Early introduction, dispersal and evolution of Delta SARS-CoV-2 in Southern Brazil, late predominance of AY.99.2 and AY.101 related lineages.

The emergence of Variants of Concern (VOC) presenting an unusual number of new mutations is one of the most remarkable features of SARS-CoV-2. The Delta variant, since its appearance, replaced the VOC Gamma, which was responsible for the major COVID-19 wave in Brazil. In this study, we performed a Delta whole-genome sequencing of 183 samples as part of a major genomic surveillance study performed since the beginning of the pandemic. Here, we showed an emergence, widespread dispersion and consolidation of the Delta variant in Rio Grande do Sul State, completely replacing the Gamma variant in a four to five months period. Performing the phylogenetic and phylodynamic analysis, the majority of the sequences generated herein were classified as AY.99.2, AY.99.2-like and AY.101. AY.99.2 Delta-related lineage has been widely reported in Brazil and in the Americas as well. Altogether, our findings provided a mutational profile of the sequences and presented high substitutions per site in the root-to-tip phylogenetic tree, corroborating studies that show the high mutational rate of SARS-CoV-2 over time.

Detailing the organic matter in suspended sediments as a tool to assess the impact of land occupation in water bodies: a case of Barigui Watershed (Southern Brazil).

Suspended sediments were collected to examine the organic carbon content and n-alkanes in order to assess the impact on water bodies caused by soil and land occupation. For this, samples from distinct areas based on the level of land occupation of the Barigui Watershed and different areas under the influence of human activities were examined. The number of industries increasing along the river was also considered. Twenty-two sediment samples were collected using a time-integrated sediment sampler. Samples were extracted with dichloromethane:methanol (DCM:methanol) (2:1) in an ultrasound bath, treated and injected using gas chromatography coupled with mass spectrometry (GC-MS) for separation and quantification. Twenty-one n-alkanes were identified and were used to track both biogenic and anthropogenic inputs. The concentration of total n-alkanes varied from 38.72 to 222.76 µg g-1, due to the impact of urbanization. Diagnostic indexes indicated high numbers of plants, bacteria and petroleum as n-alkanes sources. The following results were obtained using: carbon preference index (CPI), 1.96-2.22 (rainy season) and 2.12-5.80 (summer season); average chain length (ACL), 30.37-31.17 (rainy season) and 30.05-30.50 (summer season) and terrigenous aquatic ratio (TAR), 0.39-5.47 (rainy season) and 2.98-5.06 (summer season); n-alkanes had two main sources: terrestrial plant and petroleum. It is clear that the source of n-alkanes is different in each season (rainy and dry) demonstrated by n-alkanes occurrence. During the rainy season, there was an increase in organic matter of oil origin which was mainly associated with the increased runoff and rain drainage. Finally, the input of organic matter associated with land occupation and erosion can be distinguished by higher concentration in the most urbanized site (PB).

Seasonal variations in the intermediate metabolism in South American tree-frog Boana pulchella.

Seasonal metabolic changes can be observed in many anurans' species. In subtropical environments with environmental temperatures variations, the temperature is a factor that can influence the extent and intensity of activity in many anuran species. Nonetheless, some species of subtropical frogs may remain active throughout the year. Boana pulchella, a subtropical species, seems to be able to survive low temperatures and remain reproductively active even in the coldest months. Therefore, we hypothesized that B. pulchella presents seasonal changes in the energy metabolism to sustain activity during all year. This study evaluated the main energy substrate levels and metabolism of B. pulchella in plasma, liver and muscle of male individuals collected in winter, spring, summer and fall in the state of Rio Grande do Sul, Brazil. Our results showed that B. pulchella has a higher glycolytic oxidation rate in liver (P = 0.0152) and muscle (P = 0.0003) and higher glycogenesis from glucose in muscle (P = 0.0002) in summer, indicating the main energy substrates in this season is glucose. The higher muscle glycogen (P = 0.0008) and lower plasma glucose in fall (P = 0.0134) may indicate an anticipatory regulation for storing to the most thermally demanding cold period: winter. These results indicated seasonal differences in the main energy substrates, and these metabolic changes among seasons can be part of a metabolic adjustment allowing maintenance of reproductive activity all year in Boana pulchella species.

A first evaluation of water resource conditions after an environmental reclamation effort at a former degraded coal mining area in Southern Brazil.

In southern South America, Brazil, in the state of Santa Catarina, the neglect and lack of environmental supervision during coal mining caused the contamination of surface and groundwater by acid mine drainage (AMD). By the force of the local law, environmental reclamation actions in these abandoned areas have been carried. A scientific work of monitoring and assessment of the water resources within these areas has never been developed, as the efficacy of the reclamation strategies has never been discussed. This work aims to fill this gap by presenting and analyzing the environmental reclamation strategy of a former degraded coal mining area and its impacts on local water resources. The water monitoring plan in Area IV's was carried out in groundwater, and in lentic (ponds) and lotic (rivers) environments of surface waters, fourteen monitoring campaigns were conducted. The results showed that upstream and downstream river points have different water qualities, with the downstream points having poorer water quality, still affected by past mining activities. From the surface water perspective, the reclaiming method adopted was effective in three of the four ponds, presenting problems only in the downstream one. Two hypotheses were proposed; the first hypothesis is that contamination happens due to leaching of the material that still remains on the ponds' banks into the water. Another hypothesis is that the contamination comes from the upstream groundwater inflow into the pond, which runs through the entire area before reaching the pond. Those results serve to further access the actual monitoring perspectives as well as to better develop future reclaiming strategies.

Causes of death in beef cattle in southern Brazil.

We determined the prevalence of diseases and pathogens associated with mortality in beef cattle in the State of Rio Grande do Sul, Brazil, based on pathology laboratory submissions. Postmortem examinations were conducted on 1,277 beef cattle that died between 2008 and 2018. Information regarding age, time of the year, breed, and regional location were analyzed statistically. Most cattle were from the surrounding region of Porto Alegre, and 78.7% of the analyzed cases had diagnostic value. The diagnostic category with most cases was infectious and/or parasitic diseases (60%), followed by toxic and toxicoinfectious (25%). Most cases occurred in the fall. Major disease conditions identified included hemoprotozoal infection (18.2%), rabies (8.2%), and plant intoxications by Senecio spp. (8.5%) and Pteridium arachnoideum (4.6%). Hemoprotozoal infection occurred at a higher frequency in young cattle, mainly in animals up to 1 y old. Intoxication by Senecio spp. was more frequent in cattle 2-3 y old.

Transmission dynamics and molecular characterization of HIV-1 epidemic among therapeutic failure patients in Santa Catarina state, southern Brazil.

The HIV-1 epidemic in southern Brazil is mostly caused by subtype C, which contrasts the dominance of subtype B in the other regions of the country. Santa Catarina (SC), although the smallest state in the southern region, presents one of the highest incidences and mortality rates in Brazil due to AIDS. This work investigated the HIV-1 molecular diversity and phylogenetic transmission networks in SC state by analyzing a database of 3070 sequences of the national genotyping service. HIV-1C proved to be the most frequent subtype, with a significant increase in prevalence over time. HIV-1B was observed to be associated with highly educated men, suggesting a compartmentalization from other subtypes. Such observation was confirmed by the high frequency of HIV-1B circulating in MSM transmission networks. Identified transmission clusters were majority composed by individuals living up to 25 km away and interstate linkages were mainly between southern neighbor states. In general, individuals between 25 and 40 years old and sequences sampled after 2014 were more likely to be in transmission chains, in agreement with the universal treatment protocol launched in 2014. The present study brings new insights about HIV-1 transmission dynamics in southern Brazil.

Analysis of indoor human thermal comfort in Pelotas municipality, extreme southern Brazil.

The indoor human thermal comfort (HTC) was investigated in residences located in the Pelotas City, southern Brazil, by the effective temperature index (ETI). In this study, temperature and relative humidity were measured inside 429 houses, located in different regions of Pelotas city, from January 11 to August 27, 2019. Samples were obtained using HOBO data loggers, indoor sensors, installed in different regions of the municipality, in the context of a cohort study of children between 2 and 4 years old and their respective mothers, led by Epidemiological Research Center of the Federal University of Pelotas (UFPEL). In general, all regions had average hourly values of effective temperature index above the comfort zone in summer and below the comfort zone in the winter. In terms of spatial variability, the indoor HTC was dependent on environmental factors such as lake breeze and indoor behavior factors, such as the use of air conditioning system in the downtown buildings.

Eunotia (Bacillariophyceae) from a subtropical stream adjacent to Iguaçu National Park, Brazil, with the proposition of a new species / Eunotia (Bacillariophyceae) de um riacho subtropical adjacente ao Parque Nacional do Iguaçu, Brasil, com a proposta de uma espécie nova

Abstract: Eunotia species from a stream located in the surrounding area of the Iguaçu National Park conservation unit were analyzed. Samples were monthly collected from September 2012 to August 2013. The periphytic material, manually obtained by squeezing aquatic macrophytes, was oxidized and analyzed under light and scanning electron microscopy. Twenty-one infrageneric taxa of Eunotia were identified, measured, and illustrated. Eunotia caniculoides sp. nov. is proposed as a new species, and eight taxa are new records for Paraná state.

Resumo: Espécies de Eunotia Ehrenberg de um ambiente lótico localizado em área adjacente à unidade de conservação Parque Nacional do Iguaçu foram analisadas. As coletas foram realizadas mensalmente de setembro de 2012 a agosto de 2013. O material perifítico obtido do espremido manual de macrófitas aquáticas foi oxidado e analisado sob microscopia óptica e eletrônica de varredura. Vinte e um táxons de Eunotia foram identificados, medidos e ilustrados. Eunotia caniculoides sp. nov. é proposta como uma nova espécie e oito táxons constituem novos registros para o estado do Paraná.

Prostate examination among adult and elderly subjects in southern Brazil: a cross-sectional population-based study

ABSTRACT BACKGROUND: Population-wide screening for prostate cancer remains a controversial topic, given the need for an individualized approach to patients regarding the risks and benefits of prostate-specific antigen testing and digital rectal examination. OBJECTIVE: The aim of this study was to investigate the prevalence of, and factors associated with, prostate examination among men aged 45 or older. DESIGN AND SETTING: Cross-sectional population-based study developed in the city of Rio Grande (RS), Brazil. METHODS: The outcome of interest was a history of prostate examination (prostate-specific antigen testing or digital rectal examination). The following independent variables were analyzed: age group, skin color, marital status, schooling, economic level, leisure-time physical activity, smoking habits, excessive alcohol consumption, overweight, health insurance, visits to the doctor during the preceding year, hypertension and diabetes. After a two-stage sampling process, the final sample consisted of 281 male individuals. RESULTS: The prevalence of a history of prostate-specific antigen testing or digital rectal examination was 68.3% (95% confidence interval (CI): 62.2 to 74.5). The highest prevalence rates were observed among men aged 70 years or older (88%) and the lowest among smokers (36%). The following characteristics were found to be associated with the outcome: advanced age; marital status other than single; more schooling and higher economic status; practicing physical activity; non-smoking habits; overweight; having health insurance; and having visited a doctor during the preceding year. CONCLUSION: Approximately two thirds of the study population had been screened for prostate examination, mostly older individuals, with higher socioeconomic status and a healthier lifestyle.