26 research outputs found
Correlation of same-visit HbA1c test with laboratory-based measurements: A MetroNet study
BACKGROUND: Glycated hemoglobin (HbA1c) results vary by analytical method. Use of same-visit HbA1c testing methodology holds the promise of more efficient patient care, and improved diabetes management. Our objective was to test the feasibility of introducing a same-visit HbA1c methodology into busy family practice centers (FPC) and to calculate the correlation between the same-visit HbA1c test and the laboratory method that the clinical site was currently using for HbA1c testing. METHODS: Consecutive diabetic patients 18 years of age and older having blood samples drawn for routine laboratory analysis of HbA1c were asked to provide a capillary blood sample for same-visit testing with the BIO-RAD Micromat II. We compared the results of the same-visit test to three different laboratory methods (one FPC used two different laboratories). RESULTS: 147 paired samples were available for analysis (73 from one FPC; 74 from the other). The Pearson correlation of Micromat II and ion-exchange HPLC was 0.713 (p < 0.001). The Micromat II mean HbA1c was 6.91%, which was lower than the 7.23% from the ion-exchange HPLC analysis (p < 0.001). The correlation of Micromat II with boronate-affinity HPLC was 0.773 (p < 0.001); Micromat II mean HbA1c 6.44%, boronate-affinity HPLC mean 7.71% (p < 0.001). Correlation coefficient for Micromat II and immuno-turbidimetric analysis was 0.927 (p < 0.001); Micromat II mean HbA1c was 7.15% and mean HbA1c from the immuno-turbidimetric analysis was 7.99% (p = 0.002). Medical staff found the same-visit measurement difficult to perform due to the amount of dedicated time required for the test. CONCLUSION: For each of the laboratory methods, the correlation coefficient was lower than the 0.96 reported by the manufacturer. This might be due to variability introduced by the multiple users of the Micromat II machine. The mean HbA1c results were also consistently lower than those obtained from laboratory analysis. Additionally, the amount of dedicated time required to perform the assay may limit its usefulness in a busy clinical practice. Before introducing a same-visit HbA1c methodology, clinicians should compare the rapid results to their current method of analysis
Genomic epidemiology reveals multiple introductions of Zika virus into the United States
Zika virus (ZIKV) is causing an unprecedented epidemic linked to severe congenital abnormalities. In July 2016, mosquito-borne ZIKV transmission was reported in the continental United States; since then, hundreds of locally acquired infections have been reported in Florida. To gain insights into the timing, source, and likely route(s) of ZIKV introduction, we tracked the virus from its first detection in Florida by sequencing ZIKV genomes from infected patients and Aedes aegypti mosquitoes. We show that at least 4 introductions, but potentially as many as 40, contributed to the outbreak in Florida and that local transmission is likely to have started in the spring of 2016-several months before its initial detection. By analysing surveillance and genetic data, we show that ZIKV moved among transmission zones in Miami. Our analyses show that most introductions were linked to the Caribbean, a finding corroborated by the high incidence rates and traffic volumes from the region into the Miami area. Our study provides an understanding of how ZIKV initiates transmission in new regions
SARS-CoV-2 infection produces chronic pulmonary epithelial and immune cell dysfunction with fibrosis in mice
A subset of individuals who recover from coronavirus disease 2019 (COVID-19) develop post-acute sequelae of SARS-CoV-2 (PASC), but the mechanistic basis of PASC-associated lung abnormalities suffers from a lack of longitudinal tissue samples. The mouse-adapted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain MA10 produces an acute respiratory distress syndrome (ARDS) in mice similar to humans. To investigate PASC pathogenesis, studies of MA10-infected mice were extended from acute to clinical recovery phases. At 15 to 120 days post-virus clearance, pulmonary histologic findings included subpleural lesions composed of collagen, proliferative fibroblasts, and chronic inflammation, including tertiary lymphoid structures. Longitudinal spatial transcriptional profiling identified global reparative and fibrotic pathways dysregulated in diseased regions, similar to human COVID-19. Populations of alveolar intermediate cells, coupled with focal up-regulation of pro-fibrotic markers, were identified in persistently diseased regions. Early intervention with antiviral EIDD-2801 reduced chronic disease, and early anti-fibrotic agent (nintedanib) intervention modified early disease severity. This murine model provides opportunities to identify pathways associated with persistent SARS-CoV-2 pulmonary disease and test countermeasures to ameliorate PASC., After recovery from acute SARS-CoV-2 infection, mice exhibit chronic lung disease similar to some humans, allowing for testing of therapeutics
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers âŒ99% of the euchromatic genome and is accurate to an error rate of âŒ1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Genome sequencing reveals Zika virus diversity and spread in the Americas
Although the recent Zika virus (ZIKV) epidemic in the Americas and its link to birth defects have attracted a great deal of attention, much remains unknown about ZIKV disease epidemiology and ZIKV evolution, in part owing to a lack of genomic data. Here we address this gap in knowledge by using multiple sequencing approaches to generate 110 ZIKV genomes from clinical and mosquito samples from 10 countries and territories, greatly expanding the observed viral genetic diversity from this outbreak. We analysed the timing and patterns of introductions into distinct geographic regions; our phylogenetic evidence suggests rapid expansion of the outbreak in Brazil and multiple introductions of outbreak strains into Puerto Rico, Honduras, Colombia, other Caribbean islands, and the continental United States. We find that ZIKV circulated undetected in multiple regions for many months before the first locally transmitted cases were confirmed, highlighting the importance of surveillance of viral infections. We identify mutations with possible functional implications for ZIKV biology and pathogenesis, as well as those that might be relevant to the effectiveness of diagnostic tests
Virus genomes reveal factors that spread and sustained the Ebola epidemic.
The 2013-2016 West African epidemic caused by the Ebola virus was of unprecedented magnitude, duration and impact. Here we reconstruct the dispersal, proliferation and decline of Ebola virus throughout the region by analysing 1,610 Ebola virus genomes, which represent over 5% of the known cases. We test the association of geography, climate and demography with viral movement among administrative regions, inferring a classic 'gravity' model, with intense dispersal between larger and closer populations. Despite attenuation of international dispersal after border closures, cross-border transmission had already sown the seeds for an international epidemic, rendering these measures ineffective at curbing the epidemic. We address why the epidemic did not spread into neighbouring countries, showing that these countries were susceptible to substantial outbreaks but at lower risk of introductions. Finally, we reveal that this large epidemic was a heterogeneous and spatially dissociated collection of transmission clusters of varying size, duration and connectivity. These insights will help to inform interventions in future epidemics
Fc-mediated pan-sarbecovirus protection after alphavirus vector vaccination
Summary: Group 2B ÎČ-coronaviruses (sarbecoviruses) have caused regional and global epidemics in modern history. Here, we evaluate the mechanisms of cross-sarbecovirus protective immunity, currently less clear yet important for pan-sarbecovirus vaccine development, using a panel of alphavirus-vectored vaccines covering bat to human strains. While vaccination does not prevent virus replication, it protects against lethal heterologous disease outcomes in both severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and clade 2 bat sarbecovirus challenge models. The spike vaccines tested primarily elicit a highly S1-specific homologous neutralizing antibody response with no detectable cross-virus neutralization. Rather, non-neutralizing antibody functions, mechanistically linked to FcgR4 and spike S2, mediate cross-protection in wild-type mice. Protection is lost in FcR knockout mice, further supporting a model for non-neutralizing, protective antibodies. These data highlight the importance of FcR-mediated cross-protective immune responses in universal pan-sarbecovirus vaccine designs