Lack of Evidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spillover in Free-Living Neotropical Non-Human Primates,Brazil

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the agent of coronavirus disease 2019 (COVID-19), is responsible for the worst pandemic of the 21st century. Like all human coronaviruses, SARS-CoV-2 originated in a wildlife reservoir, most likely from bats. As SARS-CoV-2 has spread across the globe in humans, it has spilled over to infect a variety of non-human animal species in domestic, farm, and zoo settings. Additionally, a broad range of species, including one neotropical monkey, have proven to be susceptible to experimental infection with SARS-CoV-2. Together, these findings raise the specter of establishment of novel enzootic cycles of SARS-CoV-2. To assess the potential exposure of free-living non-human primates to SARS-CoV-2, we sampled 60 neotropical monkeys living in proximity to Manaus and São José do Rio Preto, two hotspots for COVID-19 in Brazil. Our molecular and serological tests detected no evidence of SAR-CoV-2 infection among these populations. While this result is reassuring, sustained surveillance efforts of wildlife living in close association with human populations is warranted, given the stochastic nature of spillover events and the enormous implications of SARS-CoV-2 spillover for human health.     

SARS-CoV-2 Delta and Omicron Variants Surge in Curitiba,Southern Brazil,and Its Impact on Overall COVID-19 Lethality

Screening efforts and genomic surveillance are essential tools to evaluate the course of the COVID-19 pandemic and assist the public healthcare system in dealing with an increasing number of infections. For the analysis of COVID-19 cases scenarios in Curitiba, Paraná, Brazil, we performed a diagnosis of positive cases, coupled with genotyping, for symptomatic and asymptomatic members of the Federal University of Paraná. We achieved over 1000 samples using RT-qPCR for diagnosis. The posterior genotyping allowed us to observe differences in the spread of strains in Curitiba, Brazil. The Delta variant was not associated with an infection wave, whereas the rapid Omicron variant spread became dominant in less than one month. We also evaluated the general vaccination coverage in the state, observing a striking reduction in lethality correlated to the vaccinated fraction of the population; although lower lethality rates were not much affected by the Omicron variant wave, the same effect was not translated in the number of infections. In summary, our results provide a general overview of the pandemic’s course in Paraná State and how there was reduction in lethality after a combination of multiple infection waves and a large-scale vaccination program.     

Qualidade da Anticoagulação Oral em Pacientes com Fibrilação Atrial em um Hospital Terciário no Brasil

BackgroundAtrial fibrillation (AF) affects 0.5% to 2.0% of the general population and is usually associated with cardiac structural diseases, hemodynamic damage, and thromboembolic complications. Oral anticoagulation prevents thromboembolic events and is monitored by the international normalized ratio (INR).ObjectivesTo evaluate INR stability in nonvalvular AF patients treated with warfarin anticoagulation, to evaluate thromboembolic or hemorrhagic complications, and to identify the group at higher risk for thromboembolic or hemorrhagic events.MethodsData from the medical records of 203 patients who received medical care at a tertiary hospital in Brazil were reviewed, and the time in therapeutic range (TTR) was calculated using the Rosendaal method. The possible TTR influencing factors were then analyzed, and the relationship between the TTR and thromboembolic or hemorrhagic events was calculated. The level of significance was 5%.ResultsThe mean TTR was 52.2%. Patients with INR instability in the adaptation phase had a lower mean TTR (46.8%) than those without instability (53.9%). Among the studied patients, 6.9% suffered hemorrhagic events, and 8.4% had a stroke. The higher risk group for stroke and bleeding consisted of patients with INR instability in the adaptation phase.ConclusionsThe quality of anticoagulation in this tertiary hospital in Brazil is similar to that in centers in developing countries. Patients with greater INR instability in the adaptation phase evolved to a lower mean TTR during follow-up, had a 4.94-fold greater chance of stroke, and had a 3.35-fold greater chance of bleeding. Thus, for this patient group, individualizing the choice of anticoagulation therapy would be advised, considering the cost-benefit ratio.     

化疗药羟喜树碱诱导Wnt信号通路抑制剂DKK-1的表达作用

目的 研究加入抗肿瘤药羟喜树碱后Wnt信号通路抑制因子DKK(dickkopf-1)在人肿瘤细胞株中的表达调控作用.方法 选择四个不同p53状态的人肝癌HepG2(HepG2,含野生型p53;Hep3B,p53缺失)和人大肠癌(LoVo,含野生型p53),人神经胶质瘤细胞(U251,p53突变)加入抗肿瘤药羟喜树碱后,观察抑制剂DKK-1以及反映Wnt信号通路功能变化的β-catenin的表达.以RT-PCR技术检测Wnt信号通路抑制因子DKK-1的表达作用,以流式细胞术检测肿瘤细胞中β-catenin的表达.结果 加人羟喜树碱24 h后DKK-ImRNA表达水平在人肝癌细胞(HepG2,含野生型p53;Hep3B,p53缺失)、人大肠癌细胞(LoVo,含野生型p53)和人神经胶质瘤细胞(U251,p53突变型)中与对照组相比表达水平显著增加.β-catenin的阳性细胞百分比强度与对照组相比表达水平降低.结论 羟喜树碱在人肝癌细胞、人大肠癌细胞、人神经胶质瘤细胞中能够诱导抑制剂DKK-1 mRNA的表达.     

Retinal removal up-regulates cannabinoid CB(1) receptors in the chick optic tectum

The endocannabinoid system has been implicated in several neurobiological processes, including neurodegeneration and neuroprotection. The aim of this study was to evaluate the effects of unilateral retinal ablation on the expression of the cannabinoid receptor subtype 1 (CB(1)) at both protein and mRNA levels in the optic tectum of the adult chick brain. After different survival times postlesion (2-30 days), the chick brains were subjected to immunohistochemical, immunoblotting, and real-time PCR procedures to evaluate CB(1) expression. TUNEL and Fluoro-Jade B were used to verify the possible occurrence of cell death, and immunostaining for the microtubule-associated protein MAP-2 was performed to verify possible dendritic remodeling after lesions. No cell death could be observed in the deafferented tectum, at least up to 30 days postlesion, although Fluoro-Jade B could reveal degenerating axons and terminals. Retinal ablation seems to generate an increase of CB(1) protein in the optic tectum and other retinorecipient visual areas, which paralleled an increase in MAP-2 staining. On the other hand, CB(1) mRNA levels were not changed after retinal ablation. Our results reveal that CB(1) expression in visual structures of the adult chick brain may be negatively regulated by the retinal innervation. The increase of CB(1) receptor expression observed after retinal removal indicates that these receptors are not presynaptic in retinal axons projecting to the tectum and suggests a role of the cannabinoid system in plasticity processes ensuing after lesions.     

Effect of endosulfan and parathion on energy reserves and physiological parameters of the terrestrial isopod Porcellio dilatatus

The in vivo effects of parathion and endosulfan on the isopod Porcellio dilatatus were investigated. Feeding parameters (food consumption and assimilation rates), growth, and energy reserves (glycogen, lipid, and protein contents) of pesticide-exposed isopods were compared with those of control animals. Isopods were exposed to a wide range of concentrations of parathion or endosulfan (0.1, 1, 10, 25, 50, 100, 250, and 500 microg/g of food) for 21 days. The route of uptake of the pesticides was through the diet (alder leaves). Results revealed that parathion induces a significant depression of glycogen, lipid, and protein contents. However, no significant effect was observed on either feeding parameters or growth. Animals fed endosulfan-contaminated food had smaller amounts of glycogen and lipid than control animals, while protein levels were similar in all treatments. Endosulfan also induced a significant decrease in food consumption and assimilation rates at the highest concentrations tested. Growth rate was also significantly affected by endosulfan. These results suggest that the isopod P. dilatatus is a suitable species for use in toxicity tests and that energy reserves could be used as effect criteria in both laboratory and field studies.     

Unlocking the in vitro anti-inflammatory and antidiabetic potential of Polygonum maritimum

Context: Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes.

Objective: Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L.

Material and methods: Antioxidant activity was determined (up to 1?mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24?h at concentrations up to 100?μg/mL and antidiabetic potential was assessed by α-amylase and α-glucosidase inhibition (up to 10?mg/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS).

Results: The methanol leaf extract had the highest activity against DPPH? (IC₅₀ =?26?μg/mL) and ABTS⁺? (IC₅₀ =?140?μg/mL), FRAP (IC₅₀ =?48?μg/mL) and CCA (IC₅₀ =?770?μg/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC₅₀ =?48?μg/mL). The methanol root (IC₅₀ =?19?μg/mL) and leaf (IC₅₀ =?29?μg/mL) extracts strongly inhibited baker’s yeast α-glucosidase, but LDCM had higher rat’s α-glucosidase inhibition (IC₅₀ =?2527?μg/mL) than acarbose (IC₅₀ =?4638?μg/mL). GC-MS analysis identified β-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities.

Conclusions: Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.