COVID-19 is having a great impact on public health, mortality and economy worldwide, in spite of the efforts to prevent its epidemy. The SARS-CoV-2 genome is different from that of MERS-CoV and SARS-CoV, although also expected to spread differently according to meteorological conditions. Our main goal is to investigate the role of some meteorological variables on the expansion of this outbreak.In this study, an exponential model relating the number of accumulated confirmed cases and time was considered. The rate of COVID-19 spread, using as criterion the doubling time of the number of confirmed cases, was used as dependent variable in a linear model that took four independent meteorological variables: temperature, humidity, precipitation and wind speed. Only China cases were considered, to control both cultural aspects and containment policies. Confirmed cases and the 4 meteorological variables were gathered between January 23 and March 1 (39 days) for the 31 provinces of Mainland China. Several periods of time were sampled for each province, obtaining more than one value for the rate of disease progression.Two different periods of time were tested, of 12 and 15 days, along with 3 and 5 different starting points in time, randomly chosen. The median value for each meteorological variable was computed, using the same time period; models with > 0.75 were selected. The rate of progression and doubling time were computed and used to fit a linear regression model. Models were evaluated using = 0.05.. CC-BY 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not peer-reviewed)The copyright holder for this preprint . https: //doi.org/10.1101//doi.org/10. /2020 Results indicate that the doubling time correlates positively with temperature and inversely with humidity, suggesting that a decrease in the rate of progression of COVID-19 with the arrival of spring and summer in the north hemisphere. A 20ºC increase is expected to delay the doubling time in 1.8 days. Those variables explain 18% of the variation in disease doubling time; the remaining 82% may be related to containment measures, general health policies, population density, transportation or cultural aspects.
Since late December 2019 a new epidemic outbreak has emerged from Whuhan, China. Rapidly the new coronavirus has spread worldwide. China
BackgroundTriple negative breast cancers (TNBC) are associated with an aggressive clinical course, earlier recurrence and short survival. BRCA – mutated tumours represent up to 25% of all TNBC. BRCA status is being studied as a predictive biomarker of response to platinum agents. However, the predictive role of BRCA status is still uncertain in this setting. Since TNBC is a very heterogeneous group of diseases, it is important to identify subsets of TNBC patients that may benefit from platinum-based therapy. This study aims to establish if the presence of a germline BRCA mutation in women with TNBC improves the pathologic complete response (pCR) after neoadjuvant chemotherapy with platinum compounds.MethodsAn extensive literature search was performed in MEDLINE, EMBASE and LILACS databases, WHO (WHO International Clinical Trials Registry Platform) and the Cochrane Controlled Trials Register Database, for online trial registries and conference proceedings. The measurement of pCR was assessed by pathology review of breast specimen and lymph nodes.ResultsThe overall OR was computed using random effects models.Seven studies were included, comprising a total of 808 TNBC patients, among which 159 were BRCA mutated. Among mutated TNBC patients, 93 (93/159; 58.4%) achieved pCR, while 410 wildtype patients (410/808; 50.7%) showed pCR (OR 1.459 CI 95% [0.953–2.34] p = 0.082) although this result did not reach statistical significance.ConclusionsThis meta-analysis shows that the addition of platinum to chemotherapy regimens in the neoadjuvant setting increases pCR rate in BRCA – mutated as compared to wild-type TNBC patients. However, this trend did not achieve statistical significance.Trial registration CRD42018092341
Objective: To analyze articles aimed at evaluating the association between diabetes, metabolic control, diabetes duration, and dental caries.Overview: A systematic search in PubMed, Cochrane Library, Embase, and Web of Science was conducted to retrieve papers in English, Portuguese, and Spanish, up to April 2019. The research strategy was constructed considering the "PECO" strategy.Only quantitative observational studies were analyzed. The risk of bias was assessed using the Newcastle-Ottawa Quality Assessment Scale. The meta-analyses were performed based on random-effects models using the statistical platform R. A total of 69 articles was included in the systematic review and 40 in the meta-analysis. Type
ObjectiveTo evaluate short-term markers of outcome in diabetic macular edema (DME).MethodsProspective interventional case series included 122 eyes of 122 patients with recently diagnosed DME. Eyes were treated with a 3-monthly loading dose of ranibizumab or aflibercept and pro re nata thereafter. Serial enhanced deep imaging SD-OCT high resolution scans were used to measure subfoveal choroidal thickness (SFCT) and central retinal thickness (CRT). Anatomic (10% CRT decrease) and functional responses (best corrected visual acuity, BCVA gain ≥5 letters) were assessed at 3 months and 6 months using univariate and multivariate analyses. Parameters tested were gender, duration of diabetes, HbA1c, hypertension, CRT, SFCT, BCVA, ellipsoid zone (EZ) status, subfoveal neuroretinal detachment (SND), anti-VEGF used and laser naivety. A logistic regression model was applied to find independent markers outcome.ResultsBCVA increased, CRT and SFCT decreased at 3 months and 6 months. Good metabolic control (p = 0.003), intact baseline EZ (p = 0.030), EZ re-grading at 3 M (p < 0.001) and laser naivety (p = 0.001) were associated with better functional outcome. The multivariate linear regression model showed that baseline SND and CRT are predictors of anatomic response, while lower baseline BCVA and intact EZ are predictors of functional response.ConclusionThe presence of SND predicts anatomic response only, while an intact EZ is critical to achieve a good functional outcome in DME.Electronic supplementary materialThe online version of this article (10.1186/s40662-018-0119-9) contains supplementary material, which is available to authorized users.
Background and Objectives: Temporomandibular joint disorders (TMJDs) are associated with pain and reduced jaw mobility. The aim of this study was to compare the outcome of patients with TMJ arthralgia when submitted to four different treatment modalities, in some cases using intra-articular injections of substances with anti-inflammatory properties and in others, a more conservative approach consisting only of a bite splint. Materials and Methods: The sample was made up of 80 patients, randomly distributed into 4 groups of 20 patients each. Each patient was given a nocturnal bite splint. One of the groups was treated with the bite splint only, while each patient in the other 3 was injected with betamethasone, sodium hyaluronate, or platelet-rich plasma in addition to using the bite splint. Two variables were assessed, namely pain intensity between 0 to 10 according to the visual analogue scale and maximum pain-free mouth opening in mm. The patients were evaluated at four different points: at the beginning of the treatment, as well as one week, one month and six months after initiation. Results: The results showed that maximum pain-free mouth opening improved in all the groups that made up the sample, with either a reduction in pain severity or with no pain. However, the group injected with platelet-rich plasma yielded the best results after six months, while patients treated with sodium hyaluronate or betamethasone obtained the best results at the end of the first week. Conclusions: We concluded that all the treatments used caused a reduction in pain and increased pain-free mouth opening. The splint combined with the platelet-rich plasma injection achieved long-term success.
Background: In recent years, classification frameworks using imaging data have shown that multimodal classification methods perform favorably over the use of a single imaging modality for the diagnosis of Alzheimer’s Disease. The currently used clinical approach often emphasizes the use of qualitative MRI and/or PET data for clinical diagnosis. Based on the hypothesis that classification of isolated imaging modalities is not predictive of their respective value in combined approaches, we investigate whether the combination of T1 Weighted MRI and diffusion tensor imaging (DTI) can yield an equivalent performance as the combination of quantitative structural MRI (sMRI) with amyloid-PET.Methods: We parcellated the brain into regions of interest (ROI) following different anatomical labeling atlases. For each region of interest different metrics were extracted from the different imaging modalities (sMRI, PiB-PET, and DTI) to be used as features. Thereafter, the feature sets were reduced using an embedded-based feature selection method. The final reduced sets were then used as input in support vector machine (SVM) classifiers. Three different base classifiers were created, one for each imaging modality, and validated using internal (n = 41) and external data from the ADNI initiative (n = 330 for sMRI, n = 148 for DTI and n = 55 for PiB-PET) sources. Finally, the classifiers were ensembled using a weighted method in order to evaluate the performance of different combinations.Results: For the base classifiers the following performance levels were found: sMRI-based classifier (accuracy, 92%; specificity, 97% and sensitivity, 87%), PiB-PET (accuracy, 91%; specificity, 89%; and sensitivity, 92%) and the lowest performance was attained with DTI (accuracy, 80%; specificity, 76%; and sensitivity, 82%). From the multimodal approaches, when integrating two modalities, the following results were observed: sMRI+PiB-PET (accuracy, 98%; specificity, 98%; and sensitivity, 99%), sMRI+DTI (accuracy, 97%; specificity, 99%; and sensitivity, 94%) and PiB-PET+DTI (accuracy, 91%; specificity, 90%; and sensitivity, 93%). Finally, the combination of all imaging modalities yielded an accuracy of 98%, specificity of 97% and sensitivity of 99%.Conclusion: Although DTI in isolation shows relatively poor performance, when combined with structural MR, it showed a surprising classification performance which was comparable to MR combined with amyloid PET. These results are consistent with the notion that white matter changes are also important in Alzheimer’s Disease.
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