27 research outputs found
Heterogeneity in pure microbial systems: experimental measurements and modeling
Cellular heterogeneity influences bioprocess performance in ways that until date are not completely elucidated. In order to account for this phenomenon in the design and operation of bioprocesses, reliable analytical and mathematical descriptions are required. We present an overview of the single cell analysis, and the mathematical modeling frameworks that have potential to be used in bioprocess control and optimization, in particular for microbial processes. In order to be suitable for bioprocess monitoring, experimental methods need to be high throughput and to require relatively short processing time. One such method used successfully under dynamic conditions is flow cytometry. Population balance and individual based models are suitable modeling options, the latter one having in particular a good potential to integrate the various data collected through experimentation. This will be highly beneficial for appropriate process design and scale up as a more rigorous approach may prevent a priori unwanted performance losses. It will also help progressing synthetic biology applications to industrial scale
Comparative Pathogenomics Reveals Horizontally Acquired Novel Virulence Genes in Fungi Infecting Cereal Hosts
Comparative analyses of pathogen genomes provide new insights into how pathogens have evolved common and divergent virulence strategies to invade related plant species. Fusarium crown and root rots are important diseases of wheat and barley world-wide. In Australia, these diseases are primarily caused by the fungal pathogen Fusarium pseudograminearum. Comparative genomic analyses showed that the F. pseudograminearum genome encodes proteins that are present in other fungal pathogens of cereals but absent in non-cereal pathogens. In some cases, these cereal pathogen specific genes were also found in bacteria associated with plants. Phylogenetic analysis of selected F. pseudograminearum genes supported the hypothesis of horizontal gene transfer into diverse cereal pathogens. Two horizontally acquired genes with no previously known role in fungal pathogenesis were studied functionally via gene knockout methods and shown to significantly affect virulence of F. pseudograminearum on the cereal hosts wheat and barley. Our results indicate using comparative genomics to identify genes specific to pathogens of related hosts reveals novel virulence genes and illustrates the importance of horizontal gene transfer in the evolution of plant infecting fungal pathogens
Children’s and adolescents’ rising animal-source food intakes in 1990–2018 were impacted by age, region, parental education and urbanicity
Animal-source foods (ASF) provide nutrition for children and adolescents’ physical and cognitive development. Here, we use data from the Global Dietary Database and Bayesian hierarchical models to quantify global, regional and national ASF intakes between 1990 and 2018 by age group across 185 countries, representing 93% of the world’s child population. Mean ASF intake was 1.9 servings per day, representing 16% of children consuming at least three daily servings. Intake was similar between boys and girls, but higher among urban children with educated parents. Consumption varied by age from 0.6 at <1 year to 2.5 servings per day at 15–19 years. Between 1990 and 2018, mean ASF intake increased by 0.5 servings per week, with increases in all regions except sub-Saharan Africa. In 2018, total ASF consumption was highest in Russia, Brazil, Mexico and Turkey, and lowest in Uganda, India, Kenya and Bangladesh. These findings can inform policy to address malnutrition through targeted ASF consumption programmes.publishedVersio
Incident type 2 diabetes attributable to suboptimal diet in 184 countries
The global burden of diet-attributable type 2 diabetes (T2D) is not well established. This risk assessment model estimated T2D incidence among adults attributable to direct and body weight-mediated effects of 11 dietary factors in 184 countries in 1990 and 2018. In 2018, suboptimal intake of these dietary factors was estimated to be attributable to 14.1 million (95% uncertainty interval (UI), 13.8–14.4 million) incident T2D cases, representing 70.3% (68.8–71.8%) of new cases globally. Largest T2D burdens were attributable to insufficient whole-grain intake (26.1% (25.0–27.1%)), excess refined rice and wheat intake (24.6% (22.3–27.2%)) and excess processed meat intake (20.3% (18.3–23.5%)). Across regions, highest proportional burdens were in central and eastern Europe and central Asia (85.6% (83.4–87.7%)) and Latin America and the Caribbean (81.8% (80.1–83.4%)); and lowest proportional burdens were in South Asia (55.4% (52.1–60.7%)). Proportions of diet-attributable T2D were generally larger in men than in women and were inversely correlated with age. Diet-attributable T2D was generally larger among urban versus rural residents and higher versus lower educated individuals, except in high-income countries, central and eastern Europe and central Asia, where burdens were larger in rural residents and in lower educated individuals. Compared with 1990, global diet-attributable T2D increased by 2.6 absolute percentage points (8.6 million more cases) in 2018, with variation in these trends by world region and dietary factor. These findings inform nutritional priorities and clinical and public health planning to improve dietary quality and reduce T2D globally.publishedVersio
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 ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 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
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Potential antidepressant overtreatment associated with office use of brief depression symptom measures.
BackgroundUse of brief depression symptom measures for identifying or screening cases may help to address depression undertreatment, but whether it also leads to diagnosis and treatment of patients with few or no symptoms-a group unlikely to have major depression or benefit from antidepressants-is unknown. We examined the associations of use of a brief depression symptom measure with depression diagnosis and antidepressant recommendation and prescription among patients with few or no depression symptoms.MethodsWe conducted exploratory observational analyses of data from a randomized trial of depression engagement interventions conducted in primary care offices in California. Analyses focused on participants scoring <10 on a study-administered 9-item Patient Health Questionnaire (PHQ-9) (completed immediately before an office visit and not disclosed to the provider) with complete chart review data (n = 595). We reviewed visit notes for evidence of practice administration of a brief symptom measure (independent of the trial) and whether the provider (1) diagnosed depression or (2) recommended and/or prescribed an antidepressant.ResultsAmong the 545 patients without a practice-administered measure, 57 (10.5%) had a visit diagnosis of depression; 9 (1.6%) were recommended and another 21 (3.8%) prescribed an antidepressant. Among the 50 patients (8.4% of total sample) with a practice-administered measure, 10 (20%) had a visit diagnosis of depression; 6 (12%) were recommended and another 6 (12%) prescribed an antidepressant. Adjusting for nesting within providers, trial intervention, stratification variables, and sample weighting, use of a brief symptom measure was associated with depression diagnosis (adjusted odds ratio, 3.2; 95% confidence interval, 1.1-9.2) and antidepressant recommendation and/or prescription (adjusted odds ratio, 3.80; 95% confidence interval, 1.0-13.9). Analyses using progressively lower PHQ-9 thresholds (<9 to <5) and examining antidepressant prescription alone yielded consistent findings. Analyses by practice-administered measure (PHQ-9 vs PHQ-2) indicated the study findings were largely associated with PHQ-9 use.ConclusionsThese exploratory findings suggest administration of brief depression symptom measures, particularly the PHQ-9, may be associated with depression diagnosis and antidepressant recommendation and prescription among patients unlikely to have major depression. If these findings are confirmed, researchers should investigate the balance of benefits and risks (eg, overdiagnosis of depression and overtreatment with antidepressants) associated with use of a brief symptom measure
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Potential antidepressant overtreatment associated with office use of brief depression symptom measures.
BackgroundUse of brief depression symptom measures for identifying or screening cases may help to address depression undertreatment, but whether it also leads to diagnosis and treatment of patients with few or no symptoms-a group unlikely to have major depression or benefit from antidepressants-is unknown. We examined the associations of use of a brief depression symptom measure with depression diagnosis and antidepressant recommendation and prescription among patients with few or no depression symptoms.MethodsWe conducted exploratory observational analyses of data from a randomized trial of depression engagement interventions conducted in primary care offices in California. Analyses focused on participants scoring <10 on a study-administered 9-item Patient Health Questionnaire (PHQ-9) (completed immediately before an office visit and not disclosed to the provider) with complete chart review data (n = 595). We reviewed visit notes for evidence of practice administration of a brief symptom measure (independent of the trial) and whether the provider (1) diagnosed depression or (2) recommended and/or prescribed an antidepressant.ResultsAmong the 545 patients without a practice-administered measure, 57 (10.5%) had a visit diagnosis of depression; 9 (1.6%) were recommended and another 21 (3.8%) prescribed an antidepressant. Among the 50 patients (8.4% of total sample) with a practice-administered measure, 10 (20%) had a visit diagnosis of depression; 6 (12%) were recommended and another 6 (12%) prescribed an antidepressant. Adjusting for nesting within providers, trial intervention, stratification variables, and sample weighting, use of a brief symptom measure was associated with depression diagnosis (adjusted odds ratio, 3.2; 95% confidence interval, 1.1-9.2) and antidepressant recommendation and/or prescription (adjusted odds ratio, 3.80; 95% confidence interval, 1.0-13.9). Analyses using progressively lower PHQ-9 thresholds (<9 to <5) and examining antidepressant prescription alone yielded consistent findings. Analyses by practice-administered measure (PHQ-9 vs PHQ-2) indicated the study findings were largely associated with PHQ-9 use.ConclusionsThese exploratory findings suggest administration of brief depression symptom measures, particularly the PHQ-9, may be associated with depression diagnosis and antidepressant recommendation and prescription among patients unlikely to have major depression. If these findings are confirmed, researchers should investigate the balance of benefits and risks (eg, overdiagnosis of depression and overtreatment with antidepressants) associated with use of a brief symptom measure
The NLRP3 inflammasome is differentially activated by pneumolysin variants and contributes to host defense in pneumococcal pneumonia
Streptococcus pneumoniae is a leading cause of pneumonia, meningitis, and sepsis. Pneumococci can be divided into >90 serotypes that show differences in the pathogenicity and invasiveness. We tested the hypotheses that the innate immune inflammasome pathway is involved in fighting pneumococcal pneumonia and that some invasive pneumococcal types are not recognized by this pathway. We show that human and murine mononuclear cells responded to S. pneumoniae expressing hemolytic pneumolysin by producing IL-1 beta. This IL-1 beta production depended on the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome. Some serotype 1, serotype 8, and serotype 7F bacteria, which have previously been associated with increased invasiveness and with production of toxins with reduced hemolytic activity, or bacterial mutants lacking pneumolysin did not stimulate notable IL-1 beta production. We further found that NLRP3 was beneficial for mice during pneumonia caused by pneumococci expressing hemolytic pneumolysin and was involved in cytokine production and maintenance of the pulmonary microvascular barrier. Overall, the inflammasome pathway is protective in pneumonia caused by pneumococci expressing hemolytic toxin but is not activated by clinically important pneumococcal sequence types causing invasive disease. The study indicates that a virulence factor polymorphism may substantially affect the recognition of bacteria by the innate immune system