Automatic COVID-19 and Common-Acquired Pneumonia Diagnosis Using Chest CT Scans.

Even with over 80% of the population being vaccinated against COVID-19, the disease continues to claim victims. Therefore, it is crucial to have a secure Computer-Aided Diagnostic system that can assist in identifying COVID-19 and determining the necessary level of care. This is especially important in the Intensive Care Unit to monitor disease progression or regression in the fight against this epidemic. To accomplish this, we merged public datasets from the literature to train lung and lesion segmentation models with five different distributions. We then trained eight CNN models for COVID-19 and Common-Acquired Pneumonia classification. If the examination was classified as COVID-19, we quantified the lesions and assessed the severity of the full CT scan. To validate the system, we used Resnetxt101 Unet++ and Mobilenet Unet for lung and lesion segmentation, respectively, achieving accuracy of 98.05%, F1-score of 98.70%, precision of 98.7%, recall of 98.7%, and specificity of 96.05%. This was accomplished in just 19.70 s per full CT scan, with external validation on the SPGC dataset. Finally, when classifying these detected lesions, we used Densenet201 and achieved accuracy of 90.47%, F1-score of 93.85%, precision of 88.42%, recall of 100.0%, and specificity of 65.07%. The results demonstrate that our pipeline can correctly detect and segment lesions due to COVID-19 and Common-Acquired Pneumonia in CT scans. It can differentiate these two classes from normal exams, indicating that our system is efficient and effective in identifying the disease and assessing the severity of the condition.

Meta-Analysis of Breast Cancer Risk in Levonorgestrel-Releasing Intrauterine System Users.

To map and assess evidence regarding use of the levonorgestrel-releasing intrauterine system (LNG-IUS) and its association with breast cancer, we conducted a systematic review and meta-analysis. A search strategy was developed using the terms "Levonorgestrel-releasing," "LNG-IUS," "intrauterine system," and "breast cancer. The electronic databases searched were MEDLINE, Embase, Cochrane Library, Latin American & Caribbean Health Sciences Literature, and Google Scholar for studies published until August 2020. We included observational studies: prospective or retrospective cohort, case-control, and cross-sectional. A total of 494 studies were identified, 294 studies were evaluated by title and abstract, and 262 were excluded because they did not meet the inclusion criteria. A total of 32 studies were read in full, and 24 were excluded. Thus, eight studies were included in the systematic review. The meta-analysis included four studies (two cohort and two case-control studies). Two subgroup analyses were performed for different study designs. The estimated relative risk for the two cohort studies (144,996 cases), with moderate-quality evidence, was 0.93 (95% confidence interval [CI], 0.840-1.03). The odds ratio estimated for the two case-control studies (5556 cases and 35987 controls), with moderate-quality evidence, was 1.07 (95% CI, 0.91-1.26). Evidence of an increased risk of breast cancer was not observed in levonorgestrel-releasing intrauterine system users.

Size Matters: An Evaluation of the Molecular Basis of Ontogenetic Modifications in the Composition of Bothrops jararacussu Snake Venom.

Ontogenetic changes in venom composition have been described in Bothrops snakes, but only a few studies have attempted to identify the targeted paralogues or the molecular mechanisms involved in modifications of gene expression during ontogeny. In this study, we decoded B. jararacussu venom gland transcripts from six specimens of varying sizes and analyzed the variability in the composition of independent venom proteomes from 19 individuals. We identified 125 distinct putative toxin transcripts, and of these, 73 were detected in venom proteomes and only 10 were involved in the ontogenetic changes. Ontogenetic variability was linearly related to snake size and did not correspond to the maturation of the reproductive stage. Changes in the transcriptome were highly predictive of changes in the venom proteome. The basic myotoxic phospholipases A2 (PLA2s) were the most abundant components in larger snakes, while in venoms from smaller snakes, PIII-class SVMPs were the major components. The snake venom metalloproteinases (SVMPs) identified corresponded to novel sequences and conferred higher pro-coagulant and hemorrhagic functions to the venom of small snakes. The mechanisms modulating venom variability are predominantly related to transcriptional events and may consist of an advantage of higher hematotoxicity and more efficient predatory function in the venom from small snakes.

Composition and Natural History of Snakes from Etá Farm region, Sete Barras, south-eastern Brazil.

Approximately 140 snake species are known to occur in the Atlantic Forest with nearly half being endemic to this ecoregion. However, the Atlantic forest is one of the most threatened tropical ecoregions, with only 16% of its original area remaining as forest. This extensive habitat loss must have had a negative effect on its snake fauna. Indeed, 53% of the threatened snakes of Brazil occur in the Atlantic forest. Therefore, basic natural history information that can potentially contribute to the conservation of Atlantic forest snakes are urgently needed. Here the natural history of a snake assemblage at Etá Farm region, Sete Barras municipality, south-eastern Brazil is described, and a visual guide and an identification key provided that can be used by researchers and local people to identify snakes from this region. Most of the species found in the field use both open areas and forests, are primarily terrestrial, present diurnal activity, and include frogs in their diet. A higher number of enlarged follicles, eggs, and/or embryos were recorded during the warm and rainy season. Seventeen different types of defensive tactics were recorded in the species found in the field. This study provides useful information for understanding the structure of snake assemblages of the Atlantic Forest and is potentially useful for conservation assessments and for designing conservation plans.

Nitric oxide signaling and the cross talk with prostanoids pathways in vascular system.

BACKGROUND: This review provides an overview of the cellular signaling of nitric oxide (NO) and prostanoids in vascular cells and the possible cross talk between their pathways, mainly in hypertension, since the imbalance of these two systems has been attributed to development of some cardiovascular diseases. It also deals with the modulation of vasodilation induced by NO donors. NO is a well-known second messenger involved in many cellular functions. CONCLUSION: In the vascular system, the NO produced by endothelial NO-synthase (eNOS) or released by NO donors acts in vascular smooth muscle cells, the binding of NO to Fe2+-heme of soluble guanylyl-cyclase (sGC) activates sGC and the production of cyclic guanosine-3-5-monophosphate (cGMP). The second messenger (cGMP) activates protein kinase G and the signaling cascade, including K+ channels. Activation of K+ channels leads to cell membrane hyperpolarization and Ca2+ channels blockade, which induce vascular relaxation. Moreover, the enzyme cyclooxygenase (COX) is also an important regulator of the vascular function by prostanoids production such as thromboxane A2 (TXA2) and prostacyclin (PGI2), which classically induce contraction and relaxation, respectively. Additionaly, studies indicate that the activity of both enzymes can be modulated by their products and reactive oxygen species (ROS) in cardiovascular diseases such as hypertension. The interaction of NO with cellular molecules, particularly the reaction of NO with ROS, determines the biological mechanisms of action and short half-life of NO. We have been working on the vascular effects of ruthenium-derived complexes that release NO. Our research group has published works on the vasodilating effects of ruthenium-derived NO donors and the mechanisms of vascular cells involved in the relaxation of the vascular smooth muscle in health and hypertensive rats. In our previous studies, we have compared the new NO donors synthesized by our group to SNP. It shows the cellular signaling of NO in the endothelial and vascular smooth muscle cells. OBJECTIVE: This work focuses on the cellular mechanisms involved in the vasodilation induced by NO and the role of prostanoids in contractile or relaxing vascular responses. Since the NO is produced by NO-synthase (NOS) or released from NO donors we also discussed the perspectives to cross talk between NO and COX pathways on the vascular tone control.

C-Type Natriuretic Peptide Induces Anti-contractile Effect Dependent on Nitric Oxide, Oxidative Stress, and NPR-B Activation in Sepsis.

AIMS: To evaluate the role of nitric oxide, reactive oxygen species (ROS), and natriuretic peptide receptor-B activation in C-type natriuretic peptide-anti-contractile effect on Phenylephrine-induced contraction in aorta isolated from septic rats. METHODS AND RESULTS: Cecal ligation and puncture (CLP) surgery was used to induce sepsis in male rats. Vascular reactivity was conducted in rat aorta and resistance mesenteric artery (RMA). Measurement of survival rate, mean arterial pressure (MAP), plasma nitric oxide, specific protein expression, and localization were evaluated. Septic rats had a survival rate about 37% at 4 h after the surgery, and these rats presented hypotension compared to control-operated (Sham) rats. Phenylephrine-induced contraction was decreased in sepsis. C-type natriuretic peptide (CNP) induced anti-contractile effect in aortas. Plasma nitric oxide was increased in sepsis. Nitric oxide-synthase but not natriuretic peptide receptor-B expression was increased in septic rat aortas. C-type natriuretic peptide-anti-contractile effect was dependent on nitric oxide-synthase, ROS, and natriuretic peptide receptor-B activation. Natriuretic peptide receptor-C, protein kinase-Cα mRNA, and basal nicotinamide adenine dinucleotide phosphate (NADPH)-dependent ROS production were lower in septic rats. Phenylephrine and CNP enhanced ROS production. However, stimulated ROS production was low in sepsis. CONCLUSION: CNP induced anti-contractile effect on Phenylephrine contraction in aortas from Sham and septic rats that was dependent on nitric oxide-synthase, ROS, and natriuretic peptide receptor-B activation.

Mesothelin as a biomarker for ovarian carcinoma: a meta-analysis.

The objective of this work was to estimate the accuracy of mesothelin as a biomarker for ovarian cancer. A quantitative systematic review was performed. A comprehensive search of the Medline, LILACS, SCOPUS, Embase, Cochrane Central Register of Controlled Trials, Biomed Central, and ISI Web of Science databases was conducted from January 1990 to June 2015. For inclusion in this systematic review, the papers must have measured mesothelin levels in at least two histological diagnoses; ovarian cancer (borderline or ovarian tumor) vs. benign or normal ovarian tissue. For each study, 2 x 2 contingency tables were constructed. We calculated the sensitivity, specificity and diagnostic odds ratio. The verification bias was performed according to QUADAS-2. Statistical analysis was performed with the software Stata 11, Meta-DiSc(r) and RevMan 5.2. Twelve studies were analyzed, which included 1,561 women. The pooled sensitivity was 0.62 (CI 95% 0.58 - 0.66) and specificity was 0.94 (CI 95% 0.92 - 0.95). The DOR was 38.92 (CI 95% 17.82 - 84.99). Our systematic review shows that mesothelin cannot serve alone as a biomarker for the detection of ovarian cancer.

Blood pressure variability provokes vascular ß-adrenoceptor desensitization in rats.

Spontaneous variation in blood pressure is defined as 'blood pressure variability' (BPV). Sinoaortic denervation (SAD) is characterized by BPV without sustained hypertension. In the present study, we investigated whether BPV could be related to vascular ß-adrenoceptor desensitization in rats. Three days after surgery (SAD and control), aortic rings were placed in an organ chamber and the relaxation stimulated by ß-adrenoceptor agonists, isoprenaline, terbutaline, BRL37344 and cyanopindolol was verified. The participation of intracellular nucleotides signaling pathways was also verified using forskolin, sodium nitroprusside and acetylcholine to induce relaxation. The effects of BPV on the increase in endothelial cytosolic Ca(2+) concentration stimulated by the ß2-adrenoceptor agonist was examined by confocal microscopy. In addition, the vascular expression of the ß2-adrenoceptor was also examined by immunohistochemistry. The results show that isoprenaline and terbutaline-induced relaxation was lower in the aortas of rats with BPV. Relaxation responses to other vasorelaxant compounds were similar in both groups of rats. Histological analysis revealed a lower level of ß2-adrenoceptor and confocal microscopy showed minor cytosolic Ca(2+) concentration in endothelial cells stimulated by the ß2-adrenoceptor agonist in rats with BPV. In conclusion, BPV leads to desensitization of the ß2-adrenoceptor, which could contribute to worse ß-adrenoceptor agonist-induced relaxation in isolated aortas.

Hyperbilirubinaemia alone cannot distinguish a perforation in acute appendicitis.

BACKGROUND: The objective of the study was to verify the accuracy of hyperbilirubinaemia as a marker for acute perforated appendicitis. METHODS: A comprehensive search of the MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials, IBECS, BIOSIS, Web of Science, SCOPUS, Congress Abstracts and Grey literature from January 1969 to July 2014. We included cross-sectional and cohort studies, prospective and retrospective, which evaluated hyperbilirubinaemia level in perforated appendicitis and compared them with histological analysis of all appendectomy specimens. RESULTS: Eleven studies were analysed, which included 5395 patients. Pooled sensitivity was 54.6% (95% confidence interval (CI), 42.8-65.8) and specificity was 70.0% (95% CI, 54.7-81.9%) using STATA. The diagnostic odds ratio was 2.82 (95% CI, 1.38-5.72%). Summary receiver operating characteristic curves were constructed. The area under the curve was 0.65. CONCLUSION: This meta-analysis showed that the value of hyperbilirubinaemia alone cannot predict acute perforated appendicitis.

Phenylephrine activates eNOS Ser 1177 phosphorylation and nitric oxide signaling in renal hypertensive rat aorta.

The endothelial nitric oxide synthase (eNOS) plays an important role in the control of the vascular tone. This work aimed to evaluate the role of an α1-adrenoceptor agonist phenylephrine (PE) on eNOS activity and downstream signaling pathway activation in normotensive (2K) and renal hypertensive (2K-1C) intact-endothelium rat aortas. Concentration-effect curves were performed for PE in intact-endothelium aortas from 2K and 2K-1C rats, in the absence of or in the presence of NOS or soluble guanylyl cyclase (sGC) inhibitor. Intact endothelium aortas were stimulated with PE in organ chambers and eNOS Ser(1177)/Thr(495) phosphorylation expression was evaluated by western blot. Nitric Oxide (NO) production was evaluated in isolated endothelial cells from 2K and 2K-1C rat aortas by flow-cytometry using NO selective fluorescent probe, DAF-2DA. The sGC activity/expression was also evaluated. PE-induced contractile response is lower in 2K-1C than in 2K intact-endothelium rat aorta. This is due to higher eNOS Ser(1177) phosphorylation in 2K-1C, which induces the eNOS overactivation. It was abolished by NOS or sGC inhibition. Phenylephrine reduces NO production in 2K as compared to the basal level, but it is not modified in 2K-1C. In PE-stimulated endothelial cells, the NO production is higher in 2K-1C than in 2K. Phenylephrine induces higher cGMP production in 2K-1C than in 2K, despite the lower expression of sGC in 2K-1C. Our results suggest that alpha1-adrenoceptor activation contributes to the increased activity of the enzyme eNOS by Ser(1177) phosphorylation in 2K-1C intact-endothelium aorta, which consequently decreases PE-induced contractile response.

Gold nanoparticle modifies nitric oxide release and vasodilation in rat aorta.

Nitric oxide (NO) plays an important role on several biological functions. Recently, it has been reported the possibility of modifying the NO release profile from the NO donors through its coupling to gold nanoparticles (AuNPs). Thus, AuNPs were synthesized and they were exposed to the NO donor ruthenium complex Cis-[Ru(bpy)2(NO)(4PySH)].(PF6)3 termed (Ru-4PySH)-forming AuNPs-{Ru-4PySH}n cluster. Our results indicate that AuNPs do not modify the maximum effect (ME) and potency (pD2) in the vasodilation induced by Ru-4PySH. Both complexes induce similar vascular relaxation in concentration-dependent way. However, the NO released from the complex AuNPs-{Ru-4PySH}n is lower than Ru-4PySH. Both complexes release only NO(0) specie, but AuNPs-{Ru-4PySH}n releases NO in constant way and exclusively in the extracellular medium. In time-course, Ru-4Py-SH was faster than AuNPs-{Ru-4PySH}n in inducing the maximum vasodilation. Inhibition of soluble guanylyl cyclase (sGC) abolished the vasodilation induced by Ru-4PYSH, but not by AuNPs-{Ru-4PySH}n. Non-selective potassium (K(+)) channel blocker TEA had no effect on the vasodilation induced by AuNPs-{Ru-4PySH}n, but it reduced the potency to Ru-4PySH. In conclusion, our results suggest that AuNPs can reduce the permeability of NO donor Ru-4PySH due to AuNPs-{Ru-4PySH}n cluster formation. AuNPs reduce NO release, but they do not impair the vasodilator effect induced by the NO donor. Ru-4PySH induces vasodilation by sGC and K(+) channels activation, while AuNPs-{Ru-4PySH}n activates mainly sGC. Taken together, these findings represent a new pharmacological strategy to control the NO release which could activate selective biological targets.

Hydrogen peroxide modulates phenylephrine-induced contractile response in renal hypertensive rat aorta.

Endothelium-derived factors play an important role in vascular tone control. This study aimed to evaluate how endothelium and reactive oxygen species (ROS) contribute to phenylephrine (PE)-induced contraction in renovascular hypertensive (2K-1C) and normotensive (2K) rats aortas. The effects of the superoxide scavenger Tiron (0.1mM and 1mM) or catalase (30 U/ml, 90 U/ml, 150 U/ml and 300 U/ml) on the PE-induced contraction were evaluated in both intact endothelium (E+) and denuded (E-) aortas. Endothelium removal increased the PE-induced contractions. The maximum contractile response decreased only in 2K-1C rat E+ aorta, and catalase (30 U/ml, 90 U/ml, 150 U/ml) partially reversed this effect. Endothelium increased the basal hydrogen peroxide (H2O2) production in 2K and 2K-1C rats aortas. PE-stimulated H2O2 production was higher in 2K-1C (E+/E-) than in 2K (E+/E-). Inhibition of the enzymes cyclooxygenase, NADPH-oxidase, xanthine-oxidase, and superoxide dismutase reduced the PE-stimulated H2O2 production in 2K-1C rat aorta. The decreased contraction to PE in 2K-1C rat aorta is partially due to endothelial H2O2 production; however, in denuded aorta, it contributes to maintaining the contractile response. Superoxide plays an important role on the PE-induced contraction in 2K rat denuded aorta, whereas in 2K-1C rat aorta, it is H2O2 that plays an important role in this effect.

Weekly fluconazole therapy for recurrent vulvovaginal candidiasis: a systematic review and meta-analysis.

OBJECTIVE: To investigate the efficacy, compared to placebo, of fluconazole 150 mg weekly, given for six months as prophylaxis against recurrent vulvovaginal candidiasis (RVVC). STUDY DESIGN: A quantitative systematic review was performed, and randomized controlled trials were included. We conducted searches at Medline, EMBASE, Lilacs, Cochrane Library and ICI Web of Science from 1980 to March 2012. We used the odds ratio (OR) with confidence intervals (CI) of 95% using a random effects model of Mantel-Haenszel. The software used was Review Manager version 5.0. RESULTS: Through the search strategies we identified 249 articles, of which only two were part of the meta-analysis. Fluconazole was more effective than placebo in reducing symptomatic episodes of VVC, immediately after treatment (OR 0.10, 95% CI 0.03-0.34), 3 months after treatment (OR 0.23, 95% CI 0.07-0.74) and 6 months after treatment (OR 0.39, 95% CI 0.24-0.64). CONCLUSION: Weekly treatment with fluconazole (150 mg) for six months is effective against RVVC.

Contribution of oxidative stress to endothelial dysfunction in hypertension.

Endothelial dysfunction is the hallmark of hypertension, which is a multifactorial disorder. In the cardiovascular system reactive oxygen species play a pivotal role in controlling the endothelial function and vascular tone. Physiologically, the endothelium-derived relaxing factors (EDRFs) and endothelium-derived contractile factors (EDCFs) that have functions on the vascular smooth muscle cells. The relaxation induced by the EDRFs nitric oxide (NO), prostacyclin, and the endothelium-derived hyperpolarization factor (EDHF) could be impaired in hypertension. The impaired ability of endothelial cells to release NO along with enhanced EDCFs production has been described to contribute to the endothelium dysfunction, which appears to lead to several cardiovascular diseases. The present review discusses the role of oxidative stress, vascular endothelium, and vascular tone control by EDRFs, mainly NO, and EDCFs in different models of experimental hypertension.

Accuracy of telomerase in estimating breast cancer risk: a systematic review and meta-analysis.

OBJECTIVE: To determine the accuracy of telomerase activity in predicting a higher risk for breast cancer. STUDY DESIGN: A quantitative systematic review was performed. Studies that detected telomerase activities in breast tissue were included. RESULTS: Twenty-five primary studies were analyzed, which included 2395 breast lesions. The proportion of breast cancer was 60.8%. Eighty-two percent (1193/1455) of breast cancer cases and 18% (169/940) of benign lesions cases were positive for telomerase activity. For breast cancer vs benign or normal breast tissue, the pooled likelihood ratio for the presence of telomerase activity was 4.5 (95% confidence interval [CI], 3.1-6.5) and the post-test probability was 88% (95% CI, 83-91). For breast cancer vs benign or normal tissue, the area under the summary receiver operating characteristic (SROC) curve was 0.89 with the Q* point value of 0.82. CONCLUSION: Our systematic review showed that telomerase activity was significantly present in breast cancer when compared with normal breast tissue or benign breast lesions.

Treatment with cannabidiol reverses oxidative stress parameters, cognitive impairment and mortality in rats submitted to sepsis by cecal ligation and puncture.

Oxidative stress plays an important role in the development of cognitive impairment in sepsis. Here we assess the effects of acute and extended administration of cannabidiol (CBD) on oxidative stress parameters in peripheral organs and in the brain, cognitive impairment, and mortality in rats submitted to sepsis by cecal ligation and perforation (CLP). To this aim, male Wistar rats underwent either sham operation or CLP. Rats subjected to CLP were treated by intraperitoneal injection with "basic support" and CBD (at 2.5, 5, or 10mg/kg once or daily for 9days after CLP) or vehicle. Six hours after CLP (early times), the rats were killed and samples from lung, liver, kidney, heart, spleen, and brain (hippocampus, striatum, and cortex) were obtained and assayed for thiobarbituric acid reactive species (TBARS) formation and protein carbonyls. On the 10th day (late times), the rats were submitted to the inhibitory avoidance task. After the test, the animals were killed and samples from lung, liver, kidney, heart, spleen, and brain (hippocampus) were obtained and assayed for TBARS formation and protein carbonyls. The acute and extended administration of CBD at different doses reduced TBARS and carbonyl levels in some organs and had no effects in others, ameliorated cognitive impairment, and significantly reduced mortality in rats submitted to CLP. Our data provide the first experimental demonstration that CBD reduces the consequences of sepsis induced by CLP in rats, by decreasing oxidative stress in peripheral organs and in the brain, improving impaired cognitive function, and decreasing mortality.