Heterogeneity in the Response of Different Subtypes of Drosophila melanogaster Midgut Cells to Viral Infections.

Single-cell RNA sequencing (scRNA-seq) offers the possibility to monitor both host and pathogens transcriptomes at the cellular level. Here, public scRNA-seq datasets from Drosophila melanogaster midgut cells were used to compare the differences in replication strategy and cellular responses between two fly picorna-like viruses, Thika virus (TV) and D. melanogaster Nora virus (DMelNV). TV exhibited lower levels of viral RNA accumulation but infected a higher number of cells compared to DMelNV. In both cases, viral RNA accumulation varied according to cell subtype. The cellular heat shock response to TV and DMelNV infection was cell-subtype- and virus-specific. Disruption of bottleneck genes at later stages of infection in the systemic response, as well as of translation-related genes in the cellular response to DMelNV in two cell subtypes, may affect the virus replication.

siRNA biogenesis and advances in topically applied dsRNA for controlling virus infections in tomato plants.

A non-transgenic approach based on RNA interference was employed to induce protection against tomato mosaic virus (ToMV) infection in tomato plants. dsRNA molecules targeting the cp gene of ToMV were topically applied on plants prior to virus inoculation. Protection was dose-dependent and sequence-specific. While no protection was achieved when 0-16 µg dsRNA were used, maximum rates of resistance (60 and 63%) were observed in doses of 200 and 400 µg/plant, respectively. Similar rates were also obtained against potato virus Y when targeting its cp gene. The protection was quickly activated upon dsRNA application and lasted for up to 4 days. In contrast, no detectable antiviral response was triggered by the dsRNA from a begomovirus genome, suggesting the method is not effective against phloem-limited DNA viruses. Deep sequencing was performed to analyze the biogenesis of siRNA populations. Although long-dsRNA remained in the treated leaves for at least 10 days, its systemic movement was not observed. Conversely, dsRNA-derived siRNA populations (mainly 21- and 22-nt) were detected in non-treated leaves, which indicates endogenous processing and transport through the plant. Altogether, this study provides critical information for the development of novel tools against plant viruses; strengths and limitations inherent to the systems are discussed.

Characteristics and outcomes of patients with COVID-19 admitted to the ICU in a university hospital in São Paulo, Brazil - study protocol.

OBJECTIVES: We designed a cohort study to describe characteristics and outcomes of patients with coronavirus disease (COVID-19) admitted to the intensive care unit (ICU) in the largest public hospital in Sao Paulo, Brazil, as Latin America becomes the epicenter of the pandemic. METHODS: This is the protocol for a study being conducted at an academic hospital in Brazil with 300 adult ICU beds dedicated to COVID-19 patients. We will include adult patients admitted to the ICU with suspected or confirmed COVID-19 during the study period. The main outcome is ICU survival at 28 days. Data will be collected prospectively and retrospectively by trained investigators from the hospital's electronic medical records, using an electronic data capture tool. We will collect data on demographics, comorbidities, severity of disease, and laboratorial test results at admission. Information on the need for advanced life support and ventilator parameters will be collected during ICU stay. Patients will be followed up for 28 days in the ICU and 60 days in the hospital. We will plot Kaplan-Meier curves to estimate ICU and hospital survival and perform survival analysis using the Cox proportional hazards model to identify the main risk factors for mortality. ClinicalTrials.gov: NCT04378582. RESULTS: We expect to include a large sample of patients with COVID-19 admitted to the ICU and to be able to provide data on admission characteristics, use of advanced life support, ICU survival at 28 days, and hospital survival at 60 days. CONCLUSIONS: This study will provide epidemiological data about critically ill patients with COVID-19 in Brazil, which could inform health policy and resource allocation in low- and middle-income countries.

Faecal Virome Analysis of Wild Animals from Brazil.

The Brazilian Cerrado fauna shows very wide diversity and can be a potential viral reservoir. Therefore, the animal's susceptibility to some virus can serve as early warning signs of potential human virus diseases. Moreover, the wild animal virome of this biome is unknown. Based on this scenario, high-throughput sequencing contributes a robust tool for the identification of known and unknown virus species in this environment. In the present study, faeces samples from cerrado birds (Psittacara leucophthalmus, Amazona aestiva, and Sicalis flaveola) and mammals (Didelphis albiventris, Sapajus libidinosus, and Galictis cuja) were collected at the Veterinary Hospital, University of Brasília. Viral nucleic acid was extracted, submitted to random amplification, and sequenced by Illumina HiSeq platform. The reads were de novo assembled, and the identities of the contigs were evaluated by Blastn and tblastx searches. Most viral contigs analyzed were closely related to bacteriophages. Novel archaeal viruses of the Smacoviridae family were detected. Moreover, sequences of members of Adenoviridae, Anelloviridae, Circoviridae, Caliciviridae, and Parvoviridae families were identified. Complete and nearly complete genomes of known anelloviruses, circoviruses, and parvoviruses were obtained, as well as putative novel species. We demonstrate that the metagenomics approach applied in this work was effective for identification of known and putative new viruses in faeces samples from Brazilian Cerrado fauna.

Antioxidative effect and phytochemical profile of natural products from the fruits of "babaçu" (Orbignia speciose) and "buriti" (Mauritia flexuosa).

Orbignya speciosa and Mauritia flexuosa are two native palm tree species found in Brazil. Their fruits are rich in edible fixed oils, which are used for many purposes in industry, such as in the manufacture of soaps, surfactants and margarines. The aim of this work was to characterize the chemical profiles and antioxidant properties of the methanol extracts obtained from the fruits of O. speciosa and M. flexuosa. The chemical prospection was carried out using specific qualitative tests to evaluate the presence of phenolic compounds (tannins and flavonoids) in the extracts of both species. The antioxidant properties of the extracts were analyzed by the following methods: production of thiobarbituric acid reactive substances (TBARS) from phospholipids, deoxyribose degradation, radical-scavenging activity-DPPH, iron chelation assay and ferric-reducing antioxidant power (FRAP). The methanolic extracts obtained from M. flexuosa and O. speciosa presented significant antioxidant activities, although M. flexuosa presented higher antioxidant activity than O. speciosa. In conclusion, M. flexuosa and O. speciosa are important sources of antioxidant substances that may be useful in the development of new products to prevent diseases associated with oxidative stress.

SAPS 3 score as a predictive factor for postoperative referral to intensive care unit.

BACKGROUND: Patients undergoing intermediate-risk surgery are typically taken to the ward postoperatively. However, some may develop complications requiring intensive care later. We aimed to evaluate the characteristics of patients undergoing intermediate-risk surgery who required late postoperative admission to the intensive care unit (ICU) and determine the predictors for this. METHODS: The study included patients undergoing intermediate-risk surgery with preoperative indication for ICU but who were taken to the ward postoperatively, because they appeared to be responding well. However, they required late ICU admission. ICU care and preoperative SAPS 3 score were evaluated. Palliative surgeries and patients readmitted to ICU were excluded. RESULTS: The study included 100 patients, 27 % of whom had late postoperative admission to the ICU. The preoperative SAPS 3 score was higher (45.4 ± 7.8 vs. 35.9 ± 7.4, P < 0.001) in patients who required delayed admission to the ICU postoperatively. Furthermore, they had undergone longer surgery (4.2 ± 1.9 vs. 2.7 ± 1.5 h, P < 0.001), and a greater proportion were gastrointestinal surgeries (14.8 vs. 5.5 %, P = 0.03) and intraoperative transfusion (18.5 vs. 5.5 % P = 0.04). In multivariate analysis, preoperative SAPS 3 and surgery duration independently predicted postoperative ICU admission, respectively (OR 1.25; 95 % CI 1.1-1.4 and OR 3.33; 95 % CI 1.7-6.3). CONCLUSION: The identification of high-risk surgical patients is essential for proper treatment; time of surgery and preoperative SAPS 3 seem to provide a useful indication of risk and may help better to characterize patients undergoing intermediate-risk surgery that demand ICU care.

Growth of the tropical zoanthid Palythoa caribaeorum (Cnidaria: Anthozoa) on reefs in northeastern Brazil.

In Brazilian reefs, zoanthids, especially Palythoa caribaeorum are fundamental for structuring the local benthic community. The objective of this study was to determine the growth rate of P. caribaeorum, and to assess the influence of the site (different beaches), season (dry and wet), location (intertidal or infralittoral zones), and human pressure associated with tourism. For one year we monitored the cover of P. caribaeorum in transects and focused on 20 colonies. We cut off a square (100 cm2) from the central part of the colony and monitored the bare area for four months in each season. The average growth rates varied from 0.015 and 0.021 cm.day(-1). The rate was homogeneous in all localities, and there was no influence from colony site, location, or touristic visitation, showing that the growth velocity may be an intrinsic characteristic of the species, with a strong genetic component. The growth rate of P. caribaeorum differed among months, and peaked in the first month after injury. The average cover varied from 6.2 to 22.9% and was lower on the reef visited by tourists. The present study corroborates the hypothesis that P. caribaeorum is important for coastal reef dynamics due to its fast and continuous growth.

A large Venous-Arterial PCO(2) Is Associated with Poor Outcomes in Surgical Patients.

Background. This study evaluated whether large venous-arterial CO(2) gap (PCO(2) gap) preoperatively is associated to poor outcome. Method. Prospective study which included adult high-risk surgical patients. The patients were pooled into two groups: wide [P(v-a)CO(2)] versus narrow [P(v-a)CO(2)]. In order to determine the best value to discriminate hospital mortality, it was applied a ROC (receiver operating characteristic) curve for the [P(v-a)CO(2)] values collected preoperatively, and the most accurate value was chosen as cut-off to define the groups. Results. The study included 66 patients. The [P(v-a)CO(2)] value preoperatively that best discriminated hospital mortality was 5.0 mmHg, area = 0.73. Preoperative patients with [P(v-a)CO(2)] more than 5.0 mmHg presented a higher hospital mortality (36.4% versus 4.5% P = 0.004), higher prevalence of circulatory shock (56.8% versus 22.7% P = 0.01) and acute renal failure postoperatively (27.3% versus 4.5% P = 0.02), and longer hospital length of stays 20.0 (14.0-30.0) versus 13.5 (9.0-25.0) days P = 0.01. Conclusions. The PCO(2) gap values more than 5.0 mmHg preoperatively were associated with worse postoperatively outcome.

Early determinants of death due to multiple organ failure after noncardiac surgery in high-risk patients.

BACKGROUND: Prediction of perioperative cardiac complications is important in the medical management of patients undergoing noncardiac surgery. However, these patients frequently die as a consequence of primary or secondary multiple organ failure (MOF), often as a result of sepsis. We investigated the early perioperative risk factors for in-hospital death due to MOF in surgical patients. METHODS: This was a prospective, multicenter, observational cohort study performed in 21 Brazilian intensive care units (ICUs). Adult patients undergoing noncardiac surgery who were admitted to the ICU within 24 hours after operation were evaluated. MOF was characterized by the presence of at least 2 organ failures. To determine the relative risk (RR) of in-hospital death due to MOF, we performed a logistic regression multivariate analysis. RESULTS: A total of 587 patients were included (mean age, 62.4 ± 17 years). ICU and hospital mortality rates were 15% and 20.6%, respectively. The main cause of death was MOF (53%). Peritonitis (RR 4.17, 95% confidence interval [CI] 1.38-12.6), diabetes (RR 3.63, 95% CI 1.17-11.2), unplanned surgery (RR 3.62, 95% CI 1.18-11.0), age (RR 1.04, 95% CI 1 0.01-1.08), and elevated serum lactate concentrations (RR 1.52, 95% CI 1.14-2.02), a high central venous pressure (RR 1.12, 95% CI 1.04-1.22), a fast heart rate (RR 3.63, 95% CI 1.17-11.2) and pH (RR 0.04, 95% CI 0.0005-0.38) on the day of admission were independent predictors of death due to MOF. CONCLUSIONS: MOF is the main cause of death after surgery in high-risk patients. Awareness of the risk factors for death due to MOF may be important in risk stratification and can suggest routes for therapy.

Manuseio da dissecçäo aórtica envolvendo artéria coronária direita / Management of aortic dissection involving the right coronary artery

É conhecido o fato de que a dissecçao aórtica pode envolver as artérias coronárias, Entretanto, somente alguns artigos fazem referência ao tratamento cirúrgico dessa afecçao. Apresentamos o seguimento de 11 pacientes acometidos por disseçao da aorta ascendente envolvendo a artéria coronária direita e que se submeteram à operaçao em nossa Instituiçao - Instituto do Coraçao do Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo. Em 2 pacientes o óstio coronariano esquerdo também foi afetado. Em 7 pacientes a dissecçao foi aguda e, em 4, crônica. A aorta ascendente foi substituída por enxerto tubular de Dacron em todos os pacientes; ponte de veia safena para a coronária direita ou enxerto de gore-tex para o óstio coronariano ou artéria coronária direita foi realizado em 9 pacientes e reimplante de ambas as coronárias dissecadas em 2. Houve 3 (27,3 por cento) mortes no pós-operatório recente, devido a síndrome de baixo débito e infarto do miocárdio. Dois pacientes acometidos por síndrome de Marfan faleceram no 14º mês de pós-operatório por doença hepática, e outro devido a rotura da aorta descendente no 39ºmês. Os 6 pacientes restantes foram acompanhados por um período que variou de 78 a 96 meses (média de 83 meses). Tal experiência sugere que, apesar de significar alto risco, o envolvimento do óstio coronariano direito na dissecçao da aorta é um acometimento que pode ser manejado com sucesso através de alguns procedimentos cirúrgicos, quando realizados antes do surgimento de complicaçoes irreversíveis.