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Human adenovirus (HAdV) is increasingly recognized as a major cause of human respiratory tract viral infections. Its outbreaks and epidemics in various populations resulted in considerable morbidity and mortality. Therefore, a rapid and specific assay for HAdV in clinical samples is of crucial importance to diagnosing HAdV infections. The present study aimed to develop and evaluate a multiplex quantitative polymerase chain reaction (qPCR) assay for the rapid detection and accurate quantification of HAdV B, C and E. The lower limit of detection for this assay was two genomic copies per reaction, and quantitative linearity ranged from 2 to 2×106 copies per reaction of the input viral DNA. Furthermore, 3,160 throat swab samples that tested HAdV negative by the immunofluorescence assay were collected and retested using the multiplex qPCR assay. The results showed that 2,906 samples were HAdV negative and the other 254 samples were HAdV positive. The HAdV species identified included B (184 samples), C (51 samples), and E (39 samples). Among the three HAdV species, HAdV B and E were detected from 8 samples, and HAdV C and E were detected from other 12 samples. The overall results demonstrated that the sensitivity and specificity of the proposed assay were 100% (254/254) and 99.6% (2894/2906), respectively. From the perspective of routine clinical diagnosis, this assay represented a rapid (≤1.5 h) and economic strategy, and had the potential to be used for the rapid and accurate diagnosis of human respiratory infections caused by HAdV B, C and E. [ABSTRACT FROM AUTHOR]

Muramidase-released protein (MRP) of Streptococcus suis serotype 2 (SS2) is an important epidemic virulence marker with an unclear role in bacterial infection. To investigate the biologic functions of MRP, 3 mutants named Dmrp, Dmrp domain 1 (Δmrp-d1), and Δmrp domain 2 (Δmrp-d2) were constructed to assess the phenotypic changes between the parental strain and the mutant strains. The results indicated that MRP domain 1 (MRP-D1, the non-conserved region of MRP from a virulent strain, a.a. 242-596) played a critical role in adherence of SS2 to host cells, compared with MRP domain 1 (MRP-D1, the non-conserved region of MRP from a low virulent strain, a.a. 239-598) or MRP domain 2 (MRP-D2, the conserved region of MRP, a.a. 848-1222). We found that MRP-D1 but not MRP-D2, could bind specifically to fibronectin (FN), factor H (FH), fibrinogen (FG), and immunoglobulin G (IgG). Additionally, we confirmed that mrp-d1 mutation significantly inhibited bacteremia and brain invasion in a mouse infection model. The mrp-d1 mutation also attenuated the intracellular survival of SS2 in RAW246.7 macrophages, shortened the growth ability in pig blood and decreased the virulence of SS2 in BALB/c mice. Furthermore, antiserum against MRP-D1 was found to dramatically impede SS2 survival in pig blood. Finally, immunization with recombinant MRP-D1 efficiently enhanced murine viability after SS2 challenge, indicating its potential use in vaccination strategies. Collectively, these results indicated that MRP-D1 is involved in SS2 virulence and eloquently demonstrate the function of MRP in pathogenesis of infection. [ABSTRACT FROM AUTHOR]

Background: Vitamin D deficiency is a public health problem worldwide. Vitamin D deficiency in pregnant women often leads to negative clinical consequence and has been distributed differently in certain latitudes. Here, we aimed to determine the prevalence of vitamin D deficiency in pregnant women in Shenzhen City and investigate the influencing factors., Methods: A total of 27,166 healthy pregnant women, undergoing prenatal examinations in our hospital between July 2014 and December 2018, were enrolled in our study. Maternal characteristics, including the duration of pregnancy, age and enrollment time, were recorded. The concentrations of serum 25(OH)D in the blood samples were detected by immunochemistry assays., Results: For the total study population, the median serum 25(OH)D concentration was 23.36 [17.98-29.51] ng/mL, and 34.3% and 42.4% of the participants exhibited vitamin D deficiency (serum 25(OH) D  < 20 ng/mL) and insufficiency (serum 25(OH)D 21-29 ng/mL), respectively. Vitamin D deficiency decreased with gestation (37.83%, 33.8%, and 29.3% for the first trimester, second trimester and third trimester, respectively, p  < .001) and decreased by age (36.03%, 35.20%, 31.86% and 29.83%, for the age groups 18-24, 25-29, 30-34 and 35-46 years, respectively, p  < .001). This prevalence had conspicuous seasonality (winter vs. autumn, OR 3.69, 95% CI: 3.42-3.99, p  < .001). Temperature was positively associated with women's serum 25(OH)D level ( r  = 0.48, p  < .001)., Conclusions: Overall, we demonstrated that vitamin D deficiency in pregnant women in Shenzhen was common and was affected by gestation, age and season/temperature.

Objective: To investigate the arsenic levels in endemic arsenism in Datong City, Shanxi Province., Methods: A total of 85 inhabitants from one village in endemic arsenism area in Datong City, Shanxi Province were collected as research subjects. The People's Republic of China health industry standard for endemic arsenism was used to identify and diagnosis the patients. Daily drinking water and soil were collected and detected by atomic fluorescence spectrometry. The content of vegetables were detected by inductively coupled plasma mass spectrometry (ICP-MS)., Results: In the study, 85 samples were collected. Arsenic concentration in the daily drinking water were 14.41 - 90.34 μg/L, and the median value was 43.88 μg/L. The arsenic concentration of vegetables were 0.001 - 0.771 mg/kg, and 43.04% of samples, were higher than the maximal permissible limit of As in food. The results that the arsenic concentration of vegetables constant changes in the leaf vegetables > tubers > fruit vegetables. The health risk of intaking arsenic pollution in vegetables up to 71.77%. The arsenic levels in village of four directions were not exceeded the Chinese standards., Conclusions: Arsenic concentration in drinking water and vegetables are high in waterborn endemic arsenicosis area of Shanxi province. Arsenic in drinking water has been considered as a primary cause of arsenism, but direct intake of arsenic from vegetables can not be ignored.