BackgroundA highly pathogenic human coronavirus (CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), has emerged in Jeddah and other places in Saudi Arabia, and has quickly spread to European and Asian countries since September 2012. Up to the 1st October 2015 it has infected at least 1593 people with a global fatality rate of about 35%. Studies to understand the virus are necessary and urgent. In the present study, MERS-CoV main protease (Mpro) is expressed; the dimerization of the protein and its relationship to catalysis are investigated.Methods and ResultsThe crystal structure of MERS-CoV Mpro indicates that it shares a similar scaffold to that of other coronaviral Mpro and consists of chymotrypsin-like domains I and II and a helical domain III of five helices. Analytical ultracentrifugation analysis demonstrated that MERS-CoV Mpro undergoes a monomer to dimer conversion in the presence of a peptide substrate. Glu169 is a key residue and plays a dual role in both dimerization and catalysis. The mutagenesis of other residues found on the dimerization interface indicate that dimerization of MERS-CoV Mpro is required for its catalytic activity. One mutation, M298R, resulted in a stable dimer with a higher level of proteolytic activity than the wild-type enzyme.ConclusionsMERS-CoV Mpro shows substrate-induced dimerization and potent proteolytic activity. A critical assessment of the residues important to these processes provides insights into the correlation between dimerization and catalysis within the coronaviral Mpro family.

To evaluate social support and loneliness as well as their association among caregivers of children with chronic kidney disease (CKD) from China during the coronavirus disease 2019 (COVID-19) pandemic. We collected data for caregivers of children with CKD and caregivers of healthy children and matched the two groups using propensity score matching (PSM). We compared the differences in social support and loneliness between the two groups after matching and analyzed the relationship between social support and loneliness in the observation group. Before PSM, we analyzed the data for 247 caregivers of children with CKD and 315 caregivers of healthy children from 13 provinces. After PSM, the two groups each included 202 caregivers. The social support score of caregivers of children with CKD was lower than that of caregivers of healthy children (P < 0.002), while the loneliness score was higher for caregivers of children with CKD than for caregivers of healthy children (P < 0.008). The social support score was negatively correlated with the loneliness score (r = −0.598, P < 0.001). Caregivers of children with CKD experienced less social support and greater loneliness than caregivers of healthy children during the COVID-19 pandemic. Therefore, greater attention should be paid to providing social support for caregivers of CKD children and to improving the ability of these caregivers to cope with loneliness.

COVID-19 the existing contagion is caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2). As of 1st March, 2021,  the statistical study shows, 114 million people all over the world have been affected by COVID-19 and in this about 2.53 million deaths have been reported with a recovery of 64.4 million cases. The most commonly testified signs of COVID-19 infection are pyrexia, tussis and tiredness; other symptoms that are less common include deprivation in senses (odor or flavor), pharyngitis, stuffy nose, cephalgia, gastroenteritis etc. Among the reported cases, approximately 10-15% progress to severe disease and 5% becomes critically ill. Most people recover at 2-6 weeks after exposure to the virus, but it is reported that there are some patients who may recur some symptoms for weeks or months after initial recovery although they are not infectious during this period. In this review article, we have briefly discussed the different diagnostic and detection measures that are being clinically practiced and the treatment methods including medicines and vaccines which has been undertaken in the fight against COVID-19. Recent advances in various regulatory measures comprising the application of biomaterials engineering (nanomaterials, biosensors, quantum dots, polymeric array-based vaccines, etc.) and the digital technologies are also discussed. Organoid cultures are also used against SARS-CoV-2 to understand the biological phenomena taking place in the human body through infection, and thereby establishing the necessary trials to control the infection. In short, there is a requirement of the combination of study from multidisciplinary areas to understand the virus better and develop more effective mitigation measures. There are still studies under examination to improve the public health and to have complete control over this novel virus.

Purpose: Meconium aspiration syndrome as one of the devasting conditions which remains the major cause of neonatal morbidity and mortality. Preterm infants affected by this life-threatening disease did not get enough attention. The aim of this study was to identify risk factors associated with mortality of preterm infant hospitalized with meconium aspiration syndrome. Methods: We undertook a case-control study in a neonatal diagnosis and treatment center in China over a ten-year period. Preterm newborns affected by meconium aspiration syndrome with early onset of respiratory distress hospitalized in NICU were included. Variables were compared between the non-survival group and survival group. Logistic regression model was conducted to identify risk factors associated with mortality. Results: Totally 92 preterm infants were included, 31(33.7%) died. Their median gestational age was 33.4 weeks, and their mean birth weight was 1925.2 g. Female[19(61.3%) vs 18(29.5%), P=0.003], arterial blood pH[7.22(±0.13) vs 7.30(±0.12), p=0.008], persistent pulmonary hypertension[19(61.3%) vs 21(34.4%), P=0.014], and pulmonary hemorrhage[16(51.6%) vs 13(21.3%), P=0.003] were associated with an increased rate of mortality. In the logistic regression model, the risk of death were found to be statistically associated with the following three factors: Female [odds ratio (OR) 3.91; 95% confidence interval(CI) (1.37-11.16); P=0.011], persistent pulmonary hypertension [OR 3.12; 95% CI (1.10-8.89); P=0.033], and pulmonary hemorrhage [OR 4.36;); P=0.006]. Conclusions: The MAS-associated fatality rates in preterm infant was significantly high. Female, persistent pulmonary hypertension, and pulmonary hemorrhage were considered independent predictors of MAS-associated mortality.