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 (which was not peer-reviewed)The copyright holder for this preprint .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

BackgroundFaces play a key role in signaling social cues such as signals of trustworthiness. Although several studies identify the amygdala as a core brain region in social cognition, quantitative approaches evaluating its role are scarce.ObjectivesThis review aimed to assess the role of the amygdala in the processing of facial trustworthiness, by analyzing its amplitude BOLD response polarity to untrustworthy versus trustworthy facial signals under fMRI tasks through a Meta-analysis of effect sizes (MA). Activation Likelihood Estimation (ALE) analyses were also conducted.Data sourcesArticles were retrieved from MEDLINE, ScienceDirect and Web-of-Science in January 2016. Following the PRISMA statement guidelines, a systematic review of original research articles in English language using the search string “(face OR facial) AND (trustworthiness OR trustworthy OR untrustworthy OR trustee) AND fMRI” was conducted.Study selection and data extractionThe MA concerned amygdala responses to facial trustworthiness for the contrast Untrustworthy vs. trustworthy faces, and included whole-brain and ROI studies. To prevent potential bias, results were considered even when at the single study level they did not survive correction for multiple comparisons or provided non-significant results. ALE considered whole-brain studies, using the same methodology to prevent bias. A summary of the methodological options (design and analysis) described in the articles was finally used to get further insight into the characteristics of the studies and to perform a subgroup analysis. Data were extracted by two authors and checked independently.Data synthesisTwenty fMRI studies were considered for systematic review. An MA of effect sizes with 11 articles (12 studies) showed high heterogeneity between studies [Q(11) = 265.68, p < .0001; I2 = 95.86%, 94.20% to 97.05%, with 95% confidence interval, CI]. Random effects analysis [RE(183) = 0.851, .422 to .969, 95% CI] supported the evidence that the (right) amygdala responds preferentially to untrustworthy faces. Moreover, two ALE analyses performed with 6 articles (7 studies) identified the amygdala, insula and medial dorsal nuclei of thalamus as structures with negative correlation with trustworthiness. Six articles/studies showed that posterior cingulate and medial frontal gyrus present positive correlations with increasing facial trustworthiness levels. Significant effects considering subgroup analysis based on methodological criteria were found for experiments using spatial smoothing, categorization of trustworthiness in 2 or 3 categories and paradigms which involve both explicit and implicit tasks.LimitationsSignificant heterogeneity between studies was found in MA, which might have arisen from inclusion of studies with smaller sample sizes and differences in methodological options. Studies using ROI analysis / small volume correction methods were more often devoted specifically to the amygdala region, with some results reporting uncorrected p-values based on mainly clinical a priori evidence...

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The imbalance between reactive oxygen species (ROS) production and their elimination by antioxidants leads to oxidative stress. Depending on their concentration, ROS can trigger apoptosis or stimulate cell proliferation. We hypothesized that oxidative stress and mitochondrial dysfunction may participate not only in apoptosis detected in some myelodysplastic syndrome (MDS) patients, but also in increasing proliferation in other patients. We investigated the involvement of oxidative stress and mitochondrial dysfunction in MDS pathogenesis, as well as assessed their diagnostic and prognostic values. Intracellular peroxides, superoxide, superoxide/peroxides ratio, reduced glutathione (GSH), and mitochondrial membrane potential (Δψ(mit)) levels were analyzed in bone marrow cells from 27 MDS patients and 12 controls, by flow cytometry. We observed that all bone marrow cell types from MDS patients had increased intracellular peroxide levels and decreased GSH content, compared with control cells. Moreover, oxidative stress levels were MDS subtype- and risk group-dependent. Low-risk patients had the highest ROS levels, which can be related with their high apoptosis; and intermediate-2-risk patients had high Δψ(mit) that may be associated with their proliferative potential. GSH levels were negatively correlated with transfusion dependency, and peroxide levels were positively correlated with serum ferritin level. GSH content proved to be an accurate parameter to discriminate patients from controls. Finally, patients with high ROS or low GSH levels, as well as high superoxide/peroxides ratio had lower overall survival. Our results suggest that oxidative stress and mitochondrial dysfunction are involved in MDS development, and that oxidative stress parameters may constitute novel diagnosis and/or prognosis biomarkers for MDS.

The influence of normal aging in early, intermediate and high-level visual processing is still poorly understood. We have addressed this important issue in a large cohort of 653 subjects divided into five distinct age groups, [20;30[, [30;40[, [40;50[, [50;60[and [60;[. We applied a broad range of psychophysical tests, testing distinct levels of the visual hierarchy, from local processing to global integration, using simple gratings (spatial contrast sensitivity -CS- using high temporal/low spatial frequency or intermediate spatial frequency static gratings), color CS using Landolt patches, moving dot stimuli (Local Speed Discrimination) and dot patterns defining 3D objects (3D Structure from Motion, 3D SFM). Aging data were fitted with linear or quadratic regression models, using the adjusted coefficient of determination (R2 a) to quantify the effect of aging. A significant effect of age was found on all visual channels tested, except for the red-green chromatic channel. The high temporal low spatial frequency contrast sensitivity channel showed a mean sensitivity loss of 0.75 dB per decade (R2 a = 0.17, p<0.001), while the lower intermediate spatial frequency channel showed a more pronounced decrease, around 2.35 dB (R2 a = 0.55, p<0.001). Concerning low-level motion perception, speed discrimination decreased 2.71°/s (R2 a = 0.18, p<0.001) and 3.15°/s (R2 a = 0.13, p<0.001) only for short presentations for horizontal and oblique meridians, respectively. The 3D SFM task, requiring high-level integration across dorsal and ventral streams, showed the strongest (quadratic) decrease of motion coherence perception with age, especially when the task was temporally constrained (R2 a = 0.54, p<0.001). These findings show that visual channels are influenced by aging into different extent, with time presenting a critical role, and high-level dorso-ventral dominance of deterioration, which accelerates with aging, in contrast to the other channels that show a linear pattern of deterioration.

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Objective: The aim of this study was to assess the pulp survival that occur in transplants of autologous teeth, by comparing two surgical techniques: the conventional technique (autotransplantation for newly formed alveoli), and an alternative technique, (autotransplants for alveoli in the initial phase of healing). In each surgical techniques were applied, randomly, either saline solution or Emdogain ® . Study Design:The study group comprised 26 patents, in which 28 teeth were transplanted to recipient sockets prepared mechanically. Of the 28 teeth transplanted, 4 were intentional replants, and of the remainer, 11 had the apex closed and 13 open. The mean age at the time of transplantation was 22.34±8.14 years (mean ± SD). The transplantation were performed by the same operator, with the informed consent of the patient and authorized by the ethical committee of the hospital. Clinical and radiological examinations were performed during 24 to 65 months (48±12.96; MED±SD), from 10 days, 1 month, 3 months, 6 months and annually to 5.6 years. Results: Only two transplanted teeth were lost, due persistent apical periodontitis, and one transplanted patient with open apex missed the treatment. In the teeth with pulp, we needed to perform root canal therapy in 9. In the 73% of the teeth with closed apex, we needed to perform root canal treatment, with no statistically significant difference found among closed apex and root canal therapy (p=0.083). In only 8% of the teeth with open apex did we need to perform root canal treatment, with an association between open apex and root canal therapy (p=0.0002). The overall success rate was 98% with significant difference for losses (p=0.0001). Conclusions: Although not a frequent procedure, it was concluded that autotransplanted teeth, performed with appropriate surgical care had a good prognosis, and can render a very useful service to the patients.