Progressive decrease of proinsulin secretion in sulphonylurea-treated type 2 diabetes

Progressive deterioration of beta-cell function is proposed as a disease-related factor of sulphonylurea (SU) failure in type 2 diabetes. If it gradually worsens over time then disease duration may mirror the progressive beta-cell deterioration. The aim of the present study is to assess whether or not disease duration is influential in remodelling the secretion pattern of insulin-like molecules and in glucose control of SU-treated type 2 diabetes. A research model is used to investigate proinsulin secreting capacity over time, using two groups of patients: i) disease duration <5 years (n=62), comprising SU responders (SUr; n=48) and SU failures (SUf; n=14); and ii) disease duration > or = 5 years (n= 37), comprising an SUr group (n=17) and an SUf group (n=20). Blood samples are taken at 0 h, 0.5 h 1 h, 2 h and 3 h during a standard oral glucose tolerance test and measured for glucose, total proinsulin (TPI), intact proinsulin (IPI) and specific insulin (SI) concentrations. Pairwise comparison of estimated marginal means of blood glucose, SI, IPI and TPI levels at each time point are carried out between groups and subgroups. (SUr vs. SUf). Homa insulin resistance index (IR index) is applied to analyse IR between the groups. It was found that patients with shorter disease duration had higher proinsulin (TPI and IPI) levels at all time points (P<0.05), together with a lower glucose level at 2 h and 3 h (P<0.05). Homa insulin index analysis showed no difference between the two groups (P=0.26). Results also showed that the SUr group had a significantly lower glucose level at Oh and 3h (P<0.05), although no significant difference in insulin and proinsulin levels was found between the SUr and SUf groups. In conclusion, proinsulin may play an important role in glucose control in SU-treated type 2 diabetes, but the effect is reduced in SUf patients.     

Circulating cell-free mitochondrial DNA fragment: A possible marker for early detection of Schistosoma japonicum

Schistosomiasis is a major public health problem that is included in the neglected tropical diseases. The early diagnosis and detection of the pathogen are of critical importance in the control of the disease. The diagnostic techniques in use include the detection of worm's eggs in fecal examination or detection of circulating antigens in immunological based assays. These traditional strategies lack sensitivity in earlier detection of the schistosomiasis. Cell-free DNA (cfDNA) that includes the fragments of parasitic DNA circulating in the body fluids of host offers an alternative mean for the rapid pathogen detection and thus is a useful diagnostic tool. In this study, we explored the usefulness of the mitochondrial cfDNA markers for the diagnosis of schistosomiasis from the experimentally infected hosts (rabbits and mice). In this study we found mitochondrial DNA fragment cytochrome B gene as persistent and useful cfDNA marker for the early detection of schistosomiasis. We evaluated the sensitivity of cfDNA marker with varying numbers of cercaria. Overall, our results suggest that cfDNA markers can be useful for developing a diagnostic tool for the detection of S. japonicum infection.     

Evolutionary genomics of recent clinical Bordetella pertussis isolates from Iran: wide circulation of multiple ptxP3 lineages and report of the first ptxP3 filamentous hemagglutinin-negative B. pertussis

Here we investigated nationwide clinical Bordetella pertussis isolated during 2005–2017 from different provinces of Iran, a country with more than 50 years whole cell vaccine immunisation history. Our results revealed the ongoing increase in the population of ptxP3/fim3–2 B. pertussis isolates in different provinces which were differentiated into nine clades. The largest clade (clade 8) which was previously found to be prevalent in Tehran was also prevalent across the country and clade 5 with ptxP3/prn9 genotype has also increased in frequency (14% of all ptxP3 isolates) in recent years. Furthermore, we detected the first ptxP3 B. pertussis isolates that does not express filamentous hemagglutinin (FhaB) as one of the major antigens of the pathogen and a key component of the acellular pertussis vaccine.     

Prevalence and genetic analysis of porcine circovirus type 2 (PCV2) and type 3 (PCV3) between 2018 and 2020 in central China

Porcine circovirus type 2 (PCV2) is the causative agent of porcine circovirus-associated diseases (PCVAD), causing substantial economic losses to the swine industry worldwide. PCV3, as a recently discovered virus, is associated with porcine dermatitis, nephropathy syndrome, reproductive failure, congenital tremors, and other clinical symptoms. To further investigate the epidemic profile and genetic diversity of the two viruses, a total of 198 samples from swine at various growth stages suspected for PCVAD on 55 different pig farms between 2018 and 2020 were analyzed for presence of PCV2 and PCV3 by using a multiplex real-time PCR assay. Among the 198 samples, 113 (57.07%) and 72 (36.36%) were positive for PCV2 and PCV3 respectively, and 39 (19.7%) were positive for PCV2 and PCV3 co-infection. Subsequently, whole genome sequences of 34 PCV2 and 19 PCV3 strains were obtained from 30 and 19 clinical samples, respectively. Of these, 8 PCV2 strains belonged to PCV2a, 10 belonged to PCV2b and 16 belonged to PCV2d, indicating PCV2d was the predominant PCV2 genotype circulating in central China. Furthermore, co-infection of different PCV2 genotype strains was identified in three samples (JZ-4, KF-2 and JY-1), and a cross-recombination was found in the ORF2 region of the sequenced 13 PCV2d strains whose putative parental strains were LN6/1999 (MF278777) and MEX/41238/2014 (KT795287) strains. The phylogenetic analysis of PCV3 showed high nucleotide identity (>98%) among sequences obtained in this study and reference sequences. These data will aid our understanding of the molecular epidemiology and evolution of PCV2 and PCV3.     

The Impact of Positive Youth Development Attributes on Posttraumatic Stress Disorder Symptoms Among Chinese Adolescents Under COVID-19

PurposeThis study examined the prevalence of posttraumatic stress disorder (PTSD) symptoms among adolescents in mainland China under COVID-19. The direct effects of the perceived threat of COVID-19 and positive youth development (PYD) qualities, as well as the moderating effect of PYD qualities on PTSD symptoms, were studied.MethodsFive schools in Chengdu, Sichuan, China, participated in this study. Two waves of data were collected before school lockdown (Wave 1, between December 2019 and January 2020) and after school resumption (Wave 2, between June 2020 and July 2020), respectively. A total of 4,981 adolescents aged above 11 years (Mean age = 13.15, SD = 1.32 at Wave 1, 51.5% girls) completed questionnaires at both waves. Students responded to measures of PYD qualities at both waves and perceived threat and PTSD symptoms at Wave 2.ResultsA total of 517 adolescents (10.4%) could be regarded as having PTSD. Results indicated significant unique main effects of perceived threat (β = .13, p < .001) and Wave 1 PYD qualities (β = ?.16, p < .001) on PTSD symptoms. Besides, results showed a significant moderating effect of PYD qualities in mitigating the negative impact of perceived threat on PTSD symptoms.ConclusionsThis study revealed the protective effect of PYD attributes in reducing the negative influence of traumatic situations such as COVID-19 on adolescent mental health. Results underscore the importance of promoting PYD qualities in adolescents in mainland China via effective PYD programs.     

Sero-epidemiology of tick-borne encephalitis in small ruminants in the Czech Republic

Tick-borne encephalitis virus (TBEV) is an arbovirus that causes severe infections in humans, and is endemic to large areas of Europe and Asia. Humans most commonly become infected with TBEV after a tick bite; however, alimentary infection can occur after consumption of unpasteurized dairy products. Milk from sheep and goats can be a source of alimentary TBE infections. In addition, sheep and goats are considered suitable sentinels for surveillance of TBEV-associated risks in endemic areas. Here we conducted a serological survey to determine the prevalence of TBEV infection among sheep and goats in the Czech Republic. In 2019–2020, a total of 310 serum samples were collected from sheep and 418 from goats, in 11 of the 14 administrative districts of the country. Sera were tested for the presence of TBEV-specific IgG by ELISA, and suspected results were validated using a virus neutralization test. Positive samples were identified in 56.7% of goat farms, and 82.4% of sheep farms, and in 9 of the 11 administrative districts examined. The seroprevalence was significantly higher among sheep (32.5%) than goats (19.7%) (p < 0.001). The present results indicate that sheep and goats have a relatively high rate of exposure to TBEV-infected ticks in most of the administrative districts of the Czech Republic. These findings confirm the usefulness of serological testing in small ruminants to determine and monitor the risk of TBEV infection in humans.     

海南省大劣按蚊实验室自然交配的驯化研究

目的 建立实验室大劣按蚊自然交配繁殖种群,为同类研究提供依据。方法 将野外捕捉并在实验室人工交配繁殖至第61代的大劣按蚊,按不同雌雄比例先后顺序置于大、中、小三种不同型号的蚊笼中喂养、驯化、观察产卵情况并计算产卵数和孵化率。结果 在大、中、小蚊笼内的分别驯化至第15、10和18代时成蚊卵的孵化率各达到82％、83．4％和80．7％,成功建立小蚊笼自然交配的大劣按蚊种群。结论 经实验室驯化的大劣按蚊能够自然交配、产卵、繁殖,有助于建立实验室自然种群。     

Evaluation of high protein intake to improve clinical outcome and nutritional status for patients with burns: a systematic review

Background and aimPatients with severe burns undergo a local and systemic response to the injury. As part of this response the patient becomes hypermetabolic. Current guidelines advise high protein intakes to counteract the catabolic response to burns, but this appears to be based on minimal experimental evidence. Hence the aim of this review was to examine the evidence for improvements in nutritional status and clinical outcome with the administration of high protein intakes for patients with burns.MethodsEight databases were searched for clinical trials with burn patients receiving two or more levels of protein intake at or above the level recommended for healthy individuals (0.75 g/kg/d) and presenting results for at least one of the following pre-defined outcomes: nitrogen balance, length of stay, weight change, survival, physical therapy index, protein fractional synthetic rate, immunological measurements, bacteraemic days, systemic antibiotic days and net protein synthesis.ResultsSix studies were included, 4 of which were randomized trials. All had major methodological limitations, in particular none was blinded. There was too much heterogeneity in study design, patient characteristics and the timing and magnitude of the interventions to justify formal meta-analysis. There was no reliable evidence of improvement in nitrogen balance, but there was some evidence of increased weight gain on higher protein diets. One small study reported an increase in survival and significant improvements in infection rates and some indicators of immune function in children. Length of stay was not significantly improved. There was weak evidence of an improvement in muscle strength and endurance but no significant increase in protein synthesis in muscle or skin, or net protein synthesis in the whole body.ConclusionThere is currently only very weak evidence to justify administering high protein diets to patients following burns.