38 research outputs found

    Forecasting Dengue, Chikungunya and Zika cases in Recife, Brazil: a spatio-temporal approach based on climate conditions, health notifications and machine learning

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    Dengue has become a challenge for many countries. Arboviruses transmitted by Aedes aegypti spread rapidly over the last decades. The emergence chikungunya fever and zika in South America poses new challenges to vector monitoring and control. This situation got worse from 2015 and 2016, with the rapid spread of chikungunya, causing fever and muscle weakness, and Zika virus, related to cases of microcephaly in newborns and the occurrence of Guillain-Barret syndrome, an autoimmune disease that affects the nervous system. The objective of this work was to construct a tool to forecast the distribution of arboviruses transmitted by the mosquito Aedes aegypti by implementing dengue, zika and chikungunya transmission predictors based on machine learning, focused on multilayer perceptrons neural networks, support vector machines and linear regression models. As a case study, we investigated forecasting models to predict the spatio-temporal distribution of cases from primary health notification data and climate variables (wind velocity, temperature and pluviometry) from Recife, Brazil, from 2013 to 2016, including 2015’s outbreak. The use of spatio-temporal analysis over multilayer perceptrons and support vector machines results proved to be very effective in predicting the distribution of arbovirus cases. The models indicate that the southern and western regions of Recife were very susceptible to outbreaks in the period under investigation. The proposed approach could be useful to support health managers and epidemiologists to prevent outbreaks of arboviruses transmitted by Aedes aegypti and promote public policies for health promotion and sanitation

    A review exploring the overarching burden of Zika virus with emphasis on epidemiological case studies from Brazil

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    This paper explores the main factors for mosquito-borne transmission of the Zika virus by focusing on environmental, anthropogenic, and social risks. A literature review was conducted bringing together related information from this genre of research from peer-reviewed publications. It was observed that environmental conditions, especially precipitation, humidity, and temperature, played a role in the transmission. Furthermore, anthropogenic factors including sanitation, urbanization, and environmental pollution promote the transmission by affecting the mosquito density. In addition, socioeconomic factors such as poverty as well as social inequality and low-quality housing have also an impact since these are social factors that limit access to certain facilities or infrastructure which, in turn, promote transmission when absent (e.g., piped water and screened windows). Finally, the paper presents short-, mid-, and long-term preventative solutions together with future perspectives. This is the first review exploring the effects of anthropogenic aspects on Zika transmission with a special emphasis in Brazil

    Semaglutide improves postprandial glucose and lipid metabolism, and delays first‐hour gastric emptying in subjects with obesity

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    Aim: To investigate the effects of semaglutide on fasting and postprandial glucose and lipid responses, and on gastric emptying. Materials and Methods: This was a randomised, double-blind, placebo-controlled, two-period, crossover trial. Subjects with obesity (N = 30) received once-weekly subcutaneous semaglutide, dose-escalated to 1.0 mg, or placebo. After each 12-week treatment period, glucose and lipid metabolism were assessed before and after standardised meals. Gastric emptying (paracetamol absorption test) and peptide YY (PYY) response were also assessed. Results: Semaglutide treatment significantly lowered fasting concentrations of glucose and glucagon, and increased insulin versus placebo (estimated treatment ratio: 0.95 [95% confidence interval: 0.91, 0.98]; 0.86 [0.75, 0.98]; 1.45 [1.20, 1.75], respectively). Postprandial glucose metabolism significantly improved with semaglutide versus placebo (incremental area under the curve 0–5 hours [iAUC0-5h]; estimated treatment difference: glucose −1.34 mmol*h/L [−2.42, −0.27]; insulin −921 pmol*h/L [−1461, −381]; C-peptide −1.42 nmol*h/L [−2.33, −0.51]). Fasting and postprandial lipid metabolism improved with semaglutide versus placebo. First-hour gastric emptying after the meal was delayed versus placebo (AUC0-1h; estimated treatment ratio: 0.73 [0.61, 0.87]); this may have contributed to the lower postprandial glucose increase in semaglutide-treated subjects. Overall gastric emptying (AUC0-5h) was not statistically different between treatments. Fasting and postprandial PYY responses were significantly lower with semaglutide versus placebo (p=0.0397 and p=0.0097, respectively). Conclusion: Semaglutide improved fasting and postprandial glucose and lipid metabolism. Overall gastric emptying was similar to placebo; however, the observed first-hour delay with semaglutide may contribute to a slower entry of glucose into the circulation

    Characterisation of sugar beet (Beta vulgaris L. ssp. vulgaris) varieties using microsatellite markers

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    <p>Abstract</p> <p>Background</p> <p>Sugar beet is an obligate outcrossing species. Varieties consist of mixtures of plants from various parental combinations. As the number of informative morphological characteristics is limited, this leads to some problems in variety registration research.</p> <p>Results</p> <p>We have developed 25 new microsatellite markers for sugar beet. A selection of 12 markers with high quality patterns was used to characterise 40 diploid and triploid varieties. For each variety 30 individual plants were genotyped. The markers amplified 3-21 different alleles. Varieties had up to 7 different alleles at one marker locus. All varieties could be distinguished. For the diploid varieties, the expected heterozygosity ranged from 0.458 to 0.744. The average inbreeding coefficient F<sub>is </sub>was 0.282 ± 0.124, but it varied widely among marker loci, from F<sub>is </sub>= +0.876 (heterozygote deficiency) to F<sub>is </sub>= -0.350 (excess of heterozygotes). The genetic differentiation among diploid varieties was relatively constant among markers (F<sub>st </sub>= 0.232 ± 0.027). Among triploid varieties the genetic differentiation was much lower (F<sub>st </sub>= 0.100 ± 0.010). The overall genetic differentiation between diploid and triploid varieties was F<sub>st </sub>= 0.133 across all loci. Part of this differentiation may coincide with the differentiation among breeders' gene pools, which was F<sub>st </sub>= 0.063.</p> <p>Conclusions</p> <p>Based on a combination of scores for individual plants all varieties can be distinguished using the 12 markers developed here. The markers may also be used for mapping and in molecular breeding. In addition, they may be employed in studying gene flow from crop to wild populations.</p

    Development and evaluation of robust molecular markers linked to disease resistance in tomato for distinctness, uniformity and stability testing

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    Molecular markers linked to phenotypically important traits are of great interest especially when traits are difficult and/or costly to be observed. In tomato where a strong focus on resistance breeding has led to the introgression of several resistance genes, resistance traits have become important characteristics in distinctness, uniformity and stability (DUS) testing for Plant Breeders Rights (PBR) applications. Evaluation of disease traits in biological assays is not always straightforward because assays are often influenced by environmental factors, and difficulties in scoring exist. In this study, we describe the development and/or evaluation of molecular marker assays for the Verticillium genes Ve1 and Ve2, the tomato mosaic virusTm1 (linked marker), the tomato mosaic virus Tm2 and Tm22 genes, the Meloidogyne incognita Mi1-2 gene, the Fusarium I (linked marker) and I2 loci, which are obligatory traits in PBR testing. The marker assays were evaluated for their robustness in a ring test and then evaluated in a set of varieties. Although in general, results between biological assays and marker assays gave highly correlated results, marker assays showed an advantage over biological tests in that the results were clearer, i.e., homozygote/heterozygote presence of the resistance gene can be detected and heterogeneity in seed lots can be identified readily. Within the UPOV framework for granting of PBR, the markers have the potential to fulfil the requirements needed for implementation in DUS testing of candidate varieties and could complement or may be an alternative to the pathogenesis tests that are carried out at present

    Global burden of cardiovascular diseases and risk factors, 1990–2019: update from the GBD 2019 study

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    Cardiovascular diseases (CVDs), principally ischemic heart disease (IHD) and stroke, are the leading cause of global mortality and a major contributor to disability. This paper reviews the magnitude of total CVD burden, including 13 underlying causes of cardiovascular death and 9 related risk factors, using estimates from the Global Burden of Disease (GBD) Study 2019. GBD, an ongoing multinational collaboration to provide comparable and consistent estimates of population health over time, used all available population-level data sources on incidence, prevalence, case fatality, mortality, and health risks to produce estimates for 204 countries and territories from 1990 to 2019. Prevalent cases of total CVD nearly doubled from 271 million (95% uncertainty interval [UI]: 257 to 285 million) in 1990 to 523 million (95% UI: 497 to 550 million) in 2019, and the number of CVD deaths steadily increased from 12.1 million (95% UI:11.4 to 12.6 million) in 1990, reaching 18.6 million (95% UI: 17.1 to 19.7 million) in 2019. The global trends for disability-adjusted life years (DALYs) and years of life lost also increased significantly, and years lived with disability doubled from 17.7 million (95% UI: 12.9 to 22.5 million) to 34.4 million (95% UI:24.9 to 43.6 million) over that period. The total number of DALYs due to IHD has risen steadily since 1990, reaching 182 million (95% UI: 170 to 194 million) DALYs, 9.14 million (95% UI: 8.40 to 9.74 million) deaths in the year 2019, and 197 million (95% UI: 178 to 220 million) prevalent cases of IHD in 2019. The total number of DALYs due to stroke has risen steadily since 1990, reaching 143 million (95% UI: 133 to 153 million) DALYs, 6.55 million (95% UI: 6.00 to 7.02 million) deaths in the year 2019, and 101 million (95% UI: 93.2 to 111 million) prevalent cases of stroke in 2019. Cardiovascular diseases remain the leading cause of disease burden in the world. CVD burden continues its decades-long rise for almost all countries outside high-income countries, and alarmingly, the age-standardized rate of CVD has begun to rise in some locations where it was previously declining in high-income countries. There is an urgent need to focus on implementing existing cost-effective policies and interventions if the world is to meet the targets for Sustainable Development Goal 3 and achieve a 30% reduction in premature mortality due to noncommunicable diseases

    Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

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    Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

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