238 research outputs found
Dataset on SARS-CoV-2 non-pharmaceutical interventions in Brazilian municipalities
Brazil has one of the fastest-growing COVID-19 epidemics worldwide. Non-pharmaceutical interventions (NPIs) have been adopted at the municipal level with asynchronous actions taken across 5,568 municipalities and the Federal District. This paper systematises the fragmented information on NPIs reporting on a novel dataset with survey responses from 4,027 mayors, covering 72.3% of all municipalities in the country. This dataset responds to the urgency to track and share findings on fragmented policies during the COVID-19 pandemic. Quantifying NPIs can help to assess the role of interventions in reducing transmission. We offer spatial and temporal details for a range of measures aimed at implementing social distancing and the dates when these measures were relaxed by local governments
Metformin Increases HDL3-Cholesterol and Decreases Subcutaneous Truncal Fat in Nondiabetic Patients with HIV-Associated Lipodystrophy
The purpose of this study was to assess metformin effects on high-density lipoprotein (HDL) composition of patients with HIV-associated lipodystrophy (LDHIV). Twenty-four adult outpatients were enrolled to receive metformin ( 1700 mg/d) during 6 months, but 2 were lost to follow-up and 6 stopped the drug due to adverse events ( gastrointestinal in 5, and excessive weight loss in 1). From the 16 subjects who completed the study, 69% were female. At baseline, 3 and 6 months, we assessed: weight, waist and hip circumferences, blood pressure, fasting glucose and insulin, homeostasis model assessment of insulin resistance (HOMA2-IR), lipids, and HDL subfractions by microultracentrifugation. At 0 and 6 months, body fat distribution was assessed by computed tomography (CT) scan (L4 and middle femur). Metformin use was associated with reduction of mean weight (-2.4Kg at 6 months; p < 0.001), body mass index, waist, waist-to-hip ratio and a marked decrease in blood pressure (p < 0.001). Subcutaneous ( p = 0.01) and total abdominal fat (p = 0.002) were reduced, but no change was found in visceral or thigh fat. No difference was detected on plasma glucose, insulin, HOMA2-IR, cholesterol or triglycerides, except for an increase in HDL3-cholesterol (from 21 mg/dL to 24 mg/dL, p = 0.002) and a reduction of nascent HDL ( the fraction of plasma HDL-cholesterol not associated to subfractions HDL2 or HDL3) (p = 0.008). Adverse effects were very common, but most were gastrointestinal and mild. Thus, metformin use in LDHIV increases HDL3-cholesterol ( probably due to improved maturation of HDL) and decreases blood pressure, weight, waist, and subcutaneous truncal fat, making this an attractive option for preventing cardiovascular disease in this population.221077978
Dynamics of early establishment of SARS-CoV-2 VOC Omicron lineages in Minas Gerais, Brazil
Brazil is one of the nations most affected by Coronavirus disease 2019 (COVID-19). The introduction and establishment of new virus variants can be related to an increase in cases and fatalities. The emergence of Omicron, the most modified SARS-CoV-2 variant, caused alarm for the public health of Brazil. In this study, we examined the effects of the Omicron introduction in Minas Gerais (MG), the second-most populous state of Brazil. A total of 430 Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) samples from November 2021 to June 2022 from Belo Horizonte (BH) city were sequenced. These newly sequenced genomes comprise 72% of all previously available SARS-CoV-2 genomes for the city. Evolutionary analysis of novel viral genomes reveals that a great diversity of Omicron sublineages have circulated in BH, a pattern in-keeping with observations across Brazil more generally. Bayesian phylogeographic reconstructions indicate that this diversity is a product of a large number of international and national importations. As observed previously, São Paulo state is shown as a significant hub for viral spread throughout the country, contributing to around 70% of all viral Omicron introductions detected in MG
Rapid viral metagenomics using SMART-9N amplification and nanopore sequencing [version 2; peer review: 2 approved]
Emerging and re-emerging viruses are a global health concern. Genome sequencing as an approach for monitoring circulating viruses is currently hampered by complex and expensive methods. Untargeted, metagenomic nanopore sequencing can provide genomic information to identify pathogens, prepare for or even prevent outbreaks. SMART (Switching Mechanism at the 5' end of RNA Template) is a popular approach for RNA-Seq but most current methods rely on oligo-dT priming to target polyadenylated mRNA molecules. We have developed two random primed SMART-Seq approaches, a sequencing agnostic approach 'SMART-9N' and a version compatible rapid adapters  available from Oxford Nanopore Technologies 'Rapid SMART-9N'. The methods were developed using viral isolates, clinical samples, and compared to a gold-standard amplicon-based method. From a Zika virus isolate the SMART-9N approach recovered 10kb of the 10.8kb RNA genome in a single nanopore read. We also obtained full genome coverage at a high depth coverage using the Rapid SMART-9N, which takes only 10 minutes and costs up to 45% less than other methods. We found the limits of detection of these methods to be 6 focus forming units (FFU)/mL with 99.02% and 87.58% genome coverage for SMART-9N and Rapid SMART-9N respectively. Yellow fever virus plasma samples and SARS-CoV-2 nasopharyngeal samples previously confirmed by RT-qPCR with a broad range of Ct-values were selected for validation. Both methods produced greater genome coverage when compared to the multiplex PCR approach and we obtained the longest single read of this study (18.5 kb) with a SARS-CoV-2 clinical sample, 60% of the virus genome using the Rapid SMART-9N method. This work demonstrates that SMART-9N and Rapid SMART-9N are sensitive, low input, and long-read compatible alternatives for RNA virus detection and genome sequencing and Rapid SMART-9N improves the cost, time, and complexity of laboratory work
Opportunistic screening for skin cancer using a mobile unit in Brazil
Abstract
Background
Skin cancer is the most common malignancy in the white population worldwide. In Brazil, the National Cancer Institute (INCA) estimates that in 2010 there will be 119,780 and 5,930 new cases of non-melanoma skin cancer and melanoma, respectively. The aim of this study was to evaluate the use of a mobile unit in the diagnosis and treatment of skin cancer in several poor regions of Brazil.
Methods
The diagnosis of skin cancer was accomplished through active medical screening in the prevention Mobile Unit (MU) of Barretos Cancer Hospital (BCH). The study population consisted of patients examined in the MU between 2004 and 2007, and their suspicious lesions were subjected to histopathological evaluation. Data were collected prospectively from standardized forms and analyzed.
Results
During the screening, 17,857 consultations were carried out. A total of 2012 (11.2%) cases of skin cancer were diagnosed. The predominant histological type reported was basal cell carcinoma (n = 1,642 or 81.6%), followed by squamous cell carcinoma (n = 303 or 15.1%), Bowen's disease (n = 25 or 1.2%), malignant melanoma (n = 23 or 1.1%), basosquamous cell carcinoma (n = 3 or 0.1%), miscellaneous lesions (12 or 0.6%), and metatypical carcinoma (n = 4 or 0.2%). Only 0.6% of lesions were stage III. There were no stage IV non-melanoma skin lesions, as well as no melanomas stages III and IV, found.
Conclusions
It was observed that the MU can be a useful tool for early skin cancer diagnosis and treatment. This program probably is important, especially in developing countries with inadequate public health systems and social inequality
Report 46: Factors driving extensive spatial and temporal fluctuations in COVID-19 fatality rates in Brazilian hospitals.
The SARS-CoV-2 Gamma variant spread rapidly across Brazil, causing substantial infection and death waves. We use individual-level patient records following hospitalisation with suspected or confirmed COVID-19 to document the extensive shocks in hospital fatality rates that followed Gamma's spread across 14 state capitals, and in which more than half of hospitalised patients died over sustained time periods. We show that extensive fluctuations in COVID-19 in-hospital fatality rates also existed prior to Gamma's detection, and were largely transient after Gamma's detection, subsiding with hospital demand. Using a Bayesian fatality rate model, we find that the geographic and temporal fluctuations in Brazil's COVID-19 in-hospital fatality rates are primarily associated with geographic inequities and shortages in healthcare capacity. We project that approximately half of Brazil's COVID-19 deaths in hospitals could have been avoided without pre-pandemic geographic inequities and without pandemic healthcare pressure. Our results suggest that investments in healthcare resources, healthcare optimization, and pandemic preparedness are critical to minimize population wide mortality and morbidity caused by highly transmissible and deadly pathogens such as SARS-CoV-2, especially in low- and middle-income countries. NOTE: The following manuscript has appeared as 'Report 46 - Factors driving extensive spatial and temporal fluctuations in COVID-19 fatality rates in Brazilian hospitals' at https://spiral.imperial.ac.uk:8443/handle/10044/1/91875 . ONE SENTENCE SUMMARY: COVID-19 in-hospital fatality rates fluctuate dramatically in Brazil, and these fluctuations are primarily associated with geographic inequities and shortages in healthcare capacity
SARS-CoV-2 antibody dynamics in blood donors and COVID-19 epidemiology in eight Brazilian state capitals: A serial cross-sectional study
BACKGROUND: The COVID-19 situation in Brazil is complex due to large differences in the shape and size of regional epidemics. Understanding these patterns is crucial to understand future outbreaks of SARS-CoV-2 or other respiratory pathogens in the country. METHODS: We tested 97,950 blood donation samples for IgG antibodies from March 2020 to March 2021 in 8 of Brazil's most populous cities. Residential postal codes were used to obtain representative samples. Weekly age- and sex-specific seroprevalence were estimated by correcting the crude seroprevalence by test sensitivity, specificity, and antibody waning. RESULTS: The inferred attack rate of SARS-CoV-2 in December 2020, before the Gamma variant of concern (VOC) was dominant, ranged from 19.3% (95% credible interval [CrI] 17.5-21.2%) in Curitiba to 75.0% (95% CrI 70.8-80.3%) in Manaus. Seroprevalence was consistently smaller in women and donors older than 55 years. The age-specific infection fatality rate (IFR) differed between cities and consistently increased with age. The infection hospitalisation rate increased significantly during the Gamma-dominated second wave in Manaus, suggesting increased morbidity of the Gamma VOC compared to previous variants circulating in Manaus. The higher disease penetrance associated with the health system's collapse increased the overall IFR by a minimum factor of 2.91 (95% CrI 2.43-3.53). CONCLUSIONS: These results highlight the utility of blood donor serosurveillance to track epidemic maturity and demonstrate demographic and spatial heterogeneity in SARS-CoV-2 spread. FUNDING: This work was supported by Itaú Unibanco 'Todos pela Saude' program; FAPESP (grants 18/14389-0, 2019/21585-0); Wellcome Trust and Royal Society Sir Henry Dale Fellowship 204311/Z/16/Z; the Gates Foundation (INV- 034540 and INV-034652); REDS-IV-P (grant HHSN268201100007I); the UK Medical Research Council (MR/S0195/1, MR/V038109/1); CAPES; CNPq (304714/2018-6); Fundação Faculdade de Medicina; Programa Inova Fiocruz-CE/Funcap - Edital 01/2020 Number: FIO-0167-00065.01.00/20 SPU N°06531047/2020; JBS - Fazer o bem faz bem
A Sensitive Assay for Virus Discovery in Respiratory Clinical Samples
In 5–40% of respiratory infections in children, the diagnostics
remain negative, suggesting that the patients might be infected with a yet
unknown pathogen. Virus discovery cDNA-AFLP (VIDISCA) is a virus discovery
method based on recognition of restriction enzyme cleavage sites, ligation of
adaptors and subsequent amplification by PCR. However, direct discovery of
unknown pathogens in nasopharyngeal swabs is difficult due to the high
concentration of ribosomal RNA (rRNA) that acts as competitor. In the current
study we optimized VIDISCA by adjusting the reverse transcription enzymes and
decreasing rRNA amplification in the reverse transcription, using hexamer
oligonucleotides that do not anneal to rRNA. Residual cDNA synthesis on rRNA
templates was further reduced with oligonucleotides that anneal to rRNA but can
not be extended due to 3′-dideoxy-C6-modification. With these
modifications >90% reduction of rRNA amplification was established.
Further improvement of the VIDISCA sensitivity was obtained by high throughput
sequencing (VIDISCA-454). Eighteen nasopharyngeal swabs were analysed, all
containing known respiratory viruses. We could identify the proper virus in the
majority of samples tested (11/18). The median load in the VIDISCA-454 positive
samples was 7.2 E5 viral genome copies/ml (ranging from 1.4 E3–7.7 E6).
Our results show that optimization of VIDISCA and subsequent
high-throughput-sequencing enhances sensitivity drastically and provides the
opportunity to perform virus discovery directly in patient material
Deletion of transketolase triggers a stringent metabolic response in promastigotes and loss of virulence in amastigotes of Leishmania mexicana
Transketolase (TKT) is part of the non-oxidative branch of the pentose phosphate pathway (PPP). Here we describe the impact of removing this enzyme from the pathogenic protozoan Leishmania mexicana. Whereas the deletion had no obvious effect on cultured promastigote forms of the parasite, the Δtkt cells were not infective to mice. Δtkt promastigotes were more susceptible to oxidative stress and various leishmanicidal drugs than wild-type, and metabolomics analysis revealed profound changes to metabolism in these cells. In addition to changes consistent with those directly related to the role of TKT in the PPP, central carbon metabolism was substantially decreased, the cells consumed significantly less glucose, flux through glycolysis diminished, and production of the main end products of metabolism was decreased. Only minor changes in RNA abundance from genes encoding enzymes in central carbon metabolism, however, were detected although fructose-1,6-bisphosphate aldolase activity was decreased two-fold in the knock-out cell line. We also showed that the dual localisation of TKT between cytosol and glycosomes is determined by the C-terminus of the enzyme and by engineering different variants of the enzyme we could alter its sub-cellular localisation. However, no effect on the overall flux of glucose was noted irrespective of whether the enzyme was found uniquely in either compartment, or in both
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