Genomic characterization and related functional genes of γ- poly glutamic acid producing Bacillus subtilis.

γ- poly glutamic acid (γ-PGA), a high molecular weight polymer, is synthesized by microorganisms and secreted into the extracellular space. Due to its excellent performance, γ-PGA has been widely used in various fields, including food, biomedical and environmental fields. In this study, we screened natto samples for two strains of Bacillus subtilis N3378-2at and N3378-3At that produce γ-PGA. We then identified the γ-PGA synthetase gene cluster (PgsB, PgsC, PgsA, YwtC and PgdS), glutamate racemase RacE, phage-derived γ-PGA hydrolase (PghB and PghC) and exo-γ-glutamyl peptidase (GGT) from the genome of these strains. Based on these γ-PGA-related protein sequences from isolated Bacillus subtilis and 181 B. subtilis obtained from GenBank, we carried out genotyping analysis and classified them into types 1-5. Since we found B. amyloliquefaciens LL3 can produce γ-PGA, we obtained the B. velezensis and B. amyloliquefaciens strains from GenBank and classified them into types 6 and 7 based on LL3. Finally, we constructed evolutionary trees for these protein sequences. This study analyzed the distribution of γ-PGA-related protein sequences in the genomes of B. subtilis, B. velezensis and B. amyloliquefaciens strains, then the evolutionary diversity of these protein sequences was analyzed, which provided novel information for the development and utilization of γ-PGA-producing strains.

Contrastive-Active Transfer Learning-Based Real-Time Adaptive Assessment Method for Power System Transient Stability.

The transient stability assessment based on machine learning faces challenges such as sample data imbalance and poor generalization. To address these problems, this paper proposes an intelligent enhancement method for real-time adaptive assessment of transient stability. In the offline phase, a convolutional neural network (CNN) is used as the base classifier. A model training method based on contrastive learning is introduced, aiming to increase the spatial distance between positive and negative samples in the mapping space. This approach effectively improves the accuracy of the model in recognizing unbalanced samples. In the online phase, when real data with different distribution characteristics from the offline data are encountered, an active transfer strategy is employed to update the model. New system samples are obtained through instance transfer from the original system, and an active sampling strategy considering uncertainty is designed to continuously select high-value samples from the new system for labeling. The model parameters are then updated by fine-tuning. This approach drastically reduces the cost of updating while improving the model's adaptability. Experiments on the IEEE39-node system verify the effectiveness of the proposed method.

Research on accuracy of material identification based on photon counting spectral CT.

BACKGROUND: Photon counting spectral CT is a significant direction in the development of CT technology and material identification is an important application of spectral CT. However, spectrum estimation in photon counting spectral CT is highly complex and may affect quantification accuracy of material identification. OBJECTIVE: To address the problem of energy spectrum estimation in photon-counting spectral CT, this study investigates empirical material decomposition algorithms to achieve accurate quantitative decomposition of the effective atomic number. METHODS: The spectrum is first calibrated using the empirical dual-energy calibration (EDEC) method and the effective atomic number is then quantitatively estimated based on the EDEC method. The accuracy of estimating the effective atomic number of materials under different calibration conditions is investigated by designing different calibration phantoms, and accurate quantitation is achieved using suitable calibration settings. Last, the validity of this method is verified through simulations and experimental studies. RESULTS: The results demonstrate that the error in estimating the effective atomic number is reduced to within 4% for low and medium Z materials, thereby enabling accurate material identification. CONCLUSION: The empirical dual-energy correction method can solve the problem of energy spectrum estimation in photon counting spectral CT. Accurate effective atomic number estimation can be achieved with suitable calibration.

Frequency and distribution of H1N1 influenza A viruses with oseltamivir-resistant mutations worldwide before and after the 2009 pandemic.

H1N1 influenza has brought serious threats to people's health and a high socioeconomic burden to society. Oseltamivir, a kind of neuraminidase (NA) inhibitor, is the second-generation specific drug that is broadly used currently. However, H1N1 influenza viruses have exhibited oseltamivir resistance in the past decades, which might be a hidden danger. To understand the frequency and distribution laws of oseltamivir-resistant viruses, we conducted a thorough and deep analysis of the available NA protein sequences of H1N1 influenza viruses worldwide from 1918 to 2020. The differences and similarities before and after 2009 were also considered since the dominant viruses changed in this period. Results showed that 3.76% of H1N1 viruses harbored oseltamivir resistance currently. Among various significative mutations, H274Y had the highest frequency of 3.30%, while the frequencies of the other mutations were far below this whether before or after 2009. The oseltamivir resistance was mainly found in three hosts, humans, swine, and avian. Different mutation sites could exhibit different distributions in each host. Our results showed that the resistance level reached a peak during the 2007-2008 influenza season and then quickly decreased in 2009. The resistance also displayed a global distribution. The densely populated countries usually had a high resistance level. However, frequent significative mutations were also found in some small countries. Our findings indicated the necessity of monitoring oseltamivir resistance around the world. The study could provide a unique perspective toward the cognition of viruses and facilitate the future study of both pandemic and drug development.

Distribution and evolution of H1N1 influenza A viruses with adamantanes-resistant mutations worldwide from 1918 to 2019.

H1N1 influenza is a kind of acute respiratory infectious disease that has a high socioeconomic and medical burden each year around the world. In the past decades, H1N1 influenza viruses have exhibited high resistance to adamantanes, which has become a serious issue. To understand the up-to-date distribution and evolution of H1N1 influenza viruses with adamantanes-resistant mutations, we conducted a deep analysis of 15875 M2 protein and 8351 MP nucleotides sequences. Results of the distribution analyses showed that 77.32% of H1N1 influenza viruses harbored-resistance mutations of which 73.52% were S31N, And the mutant variants mainly appeared in North America and Europe and H1N1 influenza viruses with S31N mutation became the circulating strains since 2009 all over the world. In addition, 80.65% of human H1N1 influenza viruses and 74.61% of swine H1N1 influenza viruses exhibited adamantanes resistance, while the frequency was only 1.86% in avian H1N1 influenza viruses. Studies from evolutionary analyses indicated that the avian-origin swine H1N1 influenza viruses replaced the classical human H1N1 influenza viruses and became the circulating strains after 2009; The interspecies transmission among avian, swine, and human strains over the past 20 years contributed to the 2009 swine influenza pandemic. Results of our study clearly clarify the historical drug resistance level of H1N1 influenza viruses around the world and demonstrated the evolution of adamantanes-resistant mutations in H1N1 influenza viruses. Our findings emphasize the necessity for monitoring the adamantanes susceptibility of H1N1 influenza viruses and draw attention to analyses of the evolution of drug-resistant H1N1 influenza variants.

Depressive, anxiety, and insomnia symptoms between population in quarantine and general population during the COVID-19 pandemic: a case-controlled study.

BACKGROUND: The COVID-19 pandemic have caused mental and psychological problems on the general population, patients, and related workers. Our study is to determine the impact of mental and psychological symptoms among population in quarantine for 2 weeks during COVID-19 pandemic. METHODS: A case-controlled study design have conducted at department of psychiatry of Shenzhen Longgang Center for Chronic Disease Control in Shenzhen, China mainland from 7th April to 15th June 2020.1674 participants (aged 18 to 65 years) in quarantine for 2 weeks and 1743 age-sex matched controls living in Shenzhen were recruited between 7th April 2020 and 15th June 2020. The assessment of depressive, anxiety, and insomnia symptoms were determined by self-reported questionnaires PHQ-9, GAD-7, and ISI, respectively. RESULTS: A total of 1674 participants in quarantine for 2 weeks and 1743 age-sex matched controls (32.6 ± 9.3 years vs. 32.7 ± 10.7 years, 49.8% vs. 47.8% females) were recruited. Population in quarantine had higher score on PHQ-9 (6.1 ± 5.5 vs. 3.0 ± 3.7, p < 0.001), GAD-7 (4.2 ± 4.7 vs. 1.9 ± 3.7, p < 0·001), and ISI (5.5 ± 5.8 vs. 3.1 ± 5.0%, p < 0.001) compared to general population. Population in quarantine showed significantly higher risks of depression (OR: 4.55, 95% CI: 3.82-5.41), anxiety (OR: 2.92, 95% CI: 2.43-3.51), and insomnia (OR: 2.40, 95% CI: 2.02-2.89), when compared to the general population. Younger, more education, non-married and lower household income showed higher risks of mental health problems. CONCLUSIONS: Population in quarantine had a higher level of depressive, anxiety, and insomnia symptoms than controls. Specifically, they were at a higher risk prevalence of depression, anxiety, and insomnia, especially the severity of depression, when compared to controls. Younger, more education, non-married, and lower income population in quarantine were at higher risks of mental health problems. Mental health professionals should pay attention to the mental and psychological symptoms for population in quarantine.

The efficacy of mind-body (Baduanjin) exercise on self-reported sleep quality and quality of life in elderly subjects with sleep disturbances: a randomized controlled trial.

OBJECTIVES: To examine the efficacy of a 24-week Baduanjin exercise program on self-reported sleep quality and quality of life in community-dwelling elderly subjects with sleep disturbances. METHODS: Community-dwelling elderly men and women meeting criteria for sleep disturbances (i.e., Pittsburgh Sleep Quality of Index (PSQI) score ≥ 5) were recruited and randomized to a Baduanjin exercise intervention group or a control group. Participants in the intervention group completed five 45-min exercise sessions per week for 24 weeks, while those in control group were instructed to maintain their usual lifestyle behaviors. RESULTS: A total of 139 participants were enrolled and randomized. Sixty-two of 67 participants in the intervention group (response rate of 92.5%) and 57 of 72 participants (response rate of 79.6%) in the control group completed intervention and follow-up. The intervention group reported significant improvements in overall sleep quality after 24 weeks compared with those randomized to control (PSQI endpoint-to-baseline change = - 2.6 ± 4.0 vs. - 0.5 ± 4.2, time × group interaction p = 0.007). Intervention group participants had higher response rates at both week 12 (23.9% vs. 9.7%, p = 0.025) and week 24 (40.3% vs. 15.3%, p = 0.001) when compared with the control group. There was a trend that the intervention group had increased quality of life (The Short Form Health Survey [SF-36] endpoint=tobaseline change 6.3 ± 10.9 vs. 2.2 ± 10.9, time × group interaction p = 0.06) when compared with the control group. CONCLUSIONS: Baduanjin exercise is an effective and feasible approach to improve self-reported sleep quality but less likely the quality of life in community-dwelling elderly men and women with sleep disturbances. TRIAL REGISTRATION: Effect of Baduanjin Exercise on the Elderly's Sleep; http://www.chictr.org.cn/listbycreater.aspx; ChiCTR1800014706, registered 1 January 2018.

The evolution and molecular characteristics of H9N2 avian influenza viruses in Jiangxi of China.

To understand the evolution and molecular characteristics of Jiangxi H9N2 viruses, we isolated 17 viruses in 2011 and analyzed their characteristics. Phylogenetic analyses revealed that their hemagglutinin genes originate from JS/1/00-like sublineage, neuraminidase genes originate from BJ/94-like sublineage, PB1, PA, NP, and NS genes all come from SH/F/98-like sublineage, PB2 genes originate from ST/163/04-like sublineage, while M genes come from G1-like sublineage. Genotype analysis showed that our isolates were classified as genotype 57. Molecular analyses indicated that our strains contained specific sites characteristic of low-pathogenic viruses. The current study once again highlights the necessity for continued surveillance of novel H9N2 viruses.

Histone acetyl transferase TIP60 inhibits the replication of influenza a virus by activation the TBK1-IRF3 pathway.

Influenza A virus (IAV) is an important pathogen that poses a severe threat to the health of humans. Nucleoprotein (NP) of IAV plays crucial roles in the viral life cycle by interacting with various cellular factors. Histone Acetyl Transferase TIP60 is a key target of several viral proteins during infection, including HIV-1 Tat, HPV E6, HTLV-1 p30II and HCMV UL27 proteins. However, Whether the interaction between the IAV NP and TIP60, and the role of TIP60 in IAV life cycle are largely unknown. Here, we showed that IAV infection up-regulated TIP60 protein and RNA expression. Overexpression of TIP60 inhibited viral protein and RNA expression and reduced the progeny viral titer. Further study revealed that TIP60 inhibited viral replication through activation of TBK1-IRF3 signaling pathway. Furthermore, we demonstrated that the NP protein of IAV interacted with TIP60. Together, these results indicate that TIP60 play a repressor in IAV infection, and it may be a possible target for antiviral drugs.

Methylation Status of the Serotonin Transporter Promoter CpG Island Is Associated With Major Depressive Disorder in Chinese Han Population: A Case-Control Study.

This study was aimed to investigate the relationship between the methylation status of serotonin transporter (5-HTT) and major depressive disorder (MDD) in Chinese Han population. A total of 96 patients with MDD and 55 healthy volunteers were recruited, and the methylation index (MtI) at six positions in the cytosine-phosphate-guanosine island of 5-HTT gene was measured for each subject using bisulfite pyrosequencing. MtIs at positions 5 and 6 were higher in patients with MDD than those in controls. According to the multivariable logistic regression analysis, MtIs at positions 4 and 5 were significantly associated with MDD. Besides, depression education was an independent risk factor, whereas higher educational levels were protective factors for MDD. In addition, positions 1 and 4 were negatively correlated with weight and diurnal variation. Therefore, 5-HTT methylation might be closely related with MDD in Chinese Han population because of the correlation with diurnal variation and weight.

Mitochondrial Dysfunction and Ca2+ Overload in Injured Sertoli Cells Exposed to Bisphenol A.

Bisphenol-A (BPA) is well known as one of endocrine-disrupting chemicals and testicular toxicant. In this present study, we determined whether BPA caused cell injury through mitochondria impairment and ROS overproduction. The cellular ROS production, mitochondrial ATP synthetase activity and Ca2+ concentration were examined. We have found BPA caused the cellular mitochondria dysfunction and followed by cell death in Sertoli cells. Moreover cytoplasm Ca2+ overload was also involved. Furthermore, pretreatment with N-acetyl-L-cysteine (NAC) could alleviate the damage by causing a remarkable decrease in ROS production and mitochondrial dysfunction. Collectively, our results showed that BPA exposure induced Sertoli cell apoptosis because of excessive ROS generation and mitochondrial dysfunction. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 823-831, 2017.

p,p'-DDE damages spermatogenesis via phospholipid hydroperoxide glutathione peroxidase depletion and mitochondria apoptosis pathway.

One, 1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE), the major metabolite of 2,2-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), is a known persistent organic pollutant (POPs) and male reproductive toxicant. However, the mechanism by which p,p'-DDE exposure causes male reproductive toxicity remains unknown. The objective of this study was to elucidate some mechanisms involved in this process, including the mitochondria apoptosis pathway and the role of phospholipid hydroperoxide glutathione peroxidase (PHGPx). Puberty male SD rats were given different doses of p,p'-DDE (0, 20, 60, 100 mg/kg body weight), after the treatment, the semen quality was evaluated. Western blotting was used to detect the PHGPx protein expression. Furthermore, real-time PCR was used to analyze the genetic expression of PHGPx, Bax, Cytochrom C (Cyt C), Apaf-1, and caspase-3 in the testis. Results indicated that after the exposure, sperm malformation rate showed a significant rise compared with the control group, and meanwhile, the sperm density and sperm motility parameters were reduced to some extent in different treated groups. The mitochondria apoptosis pathway was activated. And remarkably, the expression of PHGPx protein was greatly reduced by the exposure. We conclude that p,p'-DDE can damage spermatogenesis via PHGPx depletion and mitochondria apoptosis pathway.

Swainsonine exposure induces impairment of host immune response in pregnant BALB/c mice.

BACKGROUND: Swainsonine can cause serious disorders in reproduction of livestock, affecting both corpora lutea and reproductive hormone. The purpose of this study was to investigate the mechanisms of swainsonine about the immunotoxic effects on pregnant mice in vivo. RESULTS: The peripheral Th1/Th2 was detected by Ionomycin and phorbol myristate acetate (PMA)-stimulating peripheral blood mononuclear cells (PBMC) of phase pregnant mice. Relevant cytokines in serum was evaluated after exposed to different dose of swainsonine. Gene expression of IL-1ß, IFN-γ, TNF-α, IL-4 and IL-10 in PBMC was assessed by real-time PCR. Swainsonine caused vacuolization phenomenon of lutein cells and a dose-effect relationship. The IL-1ß, IFN-γ and TNF-α were promoted, but IL-4 and IL-10 were suppressed in serum. Swainsonine significantly increased IL-1ß, IFN-γ and TNF-α nuclear translocation and decreased IL-4 and IL-10. Swainsonine resulted in a significant shift of peripheral Th1/Th2 paradigm to Th1. CONCLUSIONS: Our data demonstrate that the immunomodulatory of swainsonine disturbed the regular immunologic state of the pregnant mice. This may increase the risk of abortion and probably resulted in serious disorders in reproduction of livestock.

Systematic review of severe fever with thrombocytopenia syndrome: virology, epidemiology, and clinical characteristics.

Severe fever with thrombocytopenia syndrome (SFTS) was firstly discovered in China in 2010, followed by several reports from many other countries worldwide. SFTS virus (SFTSV) has been identified as the causative agent of the disease and has been recognized as a public health threat. This novel Bunyavirus belongs to the Phlebovirus genus in the family Bunyaviridae. This review also describes the different aspects of virology, pathogenesis, epidemiology, and clinical symptoms on the basis of the published article surveillance data and phylogenetic analyses of viral sequences of large, medium, and small segments retrieved from database using mega 5.05, simplot 3.5.1, network 4.611, and epi information system 3.5.3 software. SFTS presents with fever, thrombocytopenia, leukocytopenia, and considerable changes in several serum biomarkers. The disease has 10~15% mortality rate, commonly because of multiorgan dysfunction. SFTSV is mainly reported in the rural areas of Central and North-Eastern China, with seasonal occurrence from May to September, mainly targeting those of ≥50 years of age. A wide range of domesticated animals, including sheep, goats, cattle, pigs, dogs, and chickens have been proven seropositive for SFTSV. Ticks, especially Haemaphysalis longicornis, are suspected to be the potential vector, which have a broad animal host range in the world. More studies are needed to elucidate the vector-animal-human ecological cycle, the pathogenic mechanisms in high level animal models and vaccine development.

The role of Pten/Akt signaling pathway involved in BPA-induced apoptosis of rat Sertoli cells.

Bisphenol-A (BPA), one of endocrine-disrupting chemicals, is a male reproductive toxicant. Previous studies have revealed the direct cytotoxicity of BPA in many cultured cells, such as mitotic aneuploidy in embryonic cells and somatic cells, and apoptosis in neurons and testicular Sertoli cells. To understand the action of BPA and assess its risk, the Pten/Akt pathway was investigated in cultured Sertoli cells to elucidate the mechanism of the reproductive effects of BPA. The results showed that over 50 µM BPA treatment could decrease the viability of Sertoli cells and cause more apoptosis. In addition, BPA could induce the increase in mRNA levels of Pten and Akt. The protein level of Pten was increased; however, the protein levels of phospho-Akt and procaspase-3 were decreased after BPA exposure. Taken together, observed results suggested that the Pten/Akt pathway might be involved in the apoptotic effects of BPA on Sertoli cells.

Relationship between domestic and wild birds in live poultry market and a novel human H7N9 virus in China.

To trace the source of the avian H7N9 viruses, we collected 99 samples from 4 live poultry markets and the family farms of 3 patients in Hangzhou city of Zhejiang province, China. We found that almost all positive samples came from chickens and ducks in live poultry markets. These results strongly suggest that the live poultry markets are the major source of recent human infections with H7N9 in Hangzhou city, Zhejiang province of China. Therefore, control measures are needed, not only in the domestic bird population, but also in the live poultry markets to reduce human H7N9 infection risk.

Pandemic influenza A(H1N1) 2009 virus in pregnancy.

Two hundred fourteen abstracts and 87 full texts regarding pregnant women infected with pandemic influenza A(H1N1) 2009 virus were systematically reviewed by using a PubMed search and assessing pandemic, clinical, laboratory test, vaccine, and control experiences. Both policy and health education were excluded. This review counted the total number of pregnant cases from different countries and analyzed their epidemic features, including trimester distribution, morbidity, hospitalization, intensive care unit admissions, maternal mortality, underlying diseases, complications, high-risk factors for death, pregnancy outcome, and clinical symptoms compared with the previous pandemic seasonal influenza A/H1N1 as compared with the general population. Early identification and treatment were the most important factors in different countries and areas examined. The vaccine and antiviral drugs that have been the most efficient means to control the novel virus appear to be safe but require more extensive study. In the future, the focus should be placed on understanding vertical transmission and the severe mechanisms.

Development of an immunomagnetic bead separation-coupled quantitative PCR method for rapid and sensitive detection of Cryptosporidium parvum oocysts in calf feces.

Cattle feces are the environmental vehicle for the zoonotic Cryptosporidium oocysts, but there are drawbacks associated with reliability of the existing methods for the detection of oocysts in the feces. Quantification of the immunomagnetic bead separation (IMS) coupled with real-time TaqMan PCR (qPCR) was accomplished by comparing the fluorescence signals obtained from the calf fecal samples of Cryptosporidium parvum oocysts with those obtained from standard dilutions of C. parvum oocysts. TaqMan qPCR assays were developed for the detection of C. parvum based on 18S rDNA gene. This IMS-qPCR assay allowed a reliable quantification of C. parvum oocysts over seven orders of magnitude with a baseline sensitivity of 8.7 oocysts. The newly developed IMS-qPCR technique proved specific as confirmed by negative reactivity against a wide panel of non-parvum Cryptosporidium oocysts. As a field application, experimentally infected calves (15 infected and 9 non-infected) were screened for oocysts shedding on 16, 18, and 21 days postinfection. Acid-fast staining microscopy of infected calves revealed oocysts in the feces of 11, 7, and 4 calves, respectively, compared to 15, 15, and 12 in case of screening by IMS-qPCR. Taken together, the proposed IMS-qPCR method significantly improved the diagnostic capacity for C. parvum infection in calves, making the technique a useful, sensitive, reliable, and time-saving.

Marine natural products: potential agents for depression treatment.

Depression is a common psychiatric disorder. Due to the disadvantages of current clinical drugs, including poor efficacy and unnecessary side effects, research has shifted to novel natural products with minimal or no adverse effects as therapeutic alternatives. The ocean is a vast ecological home, with a wide variety of organisms that can produce a large number of natural products with unique structures, some of which have neuroprotective effects and are a valuable source for the development of new drugs for depression. In this review, we analyzed preclinical and clinical studies of natural products derived from marine organisms with antidepressant potential, including the effects on the pathophysiology of depression, and the underlying mechanisms of these effects. It is expected to provide a reference for the development of new antidepressant drugs.

Microvascular abnormalities induced by hand-transmitted vibration reflects in finger systolic blood pressure: a cross-sectional study in China.

OBJECTIVE: Local vibration can cause microcirculatory abnormalities such as blood stasis and symmetrical intermittent digital artery vasospasm. Finger SBP (FSBP) measurement is a potential way of assessing vascular components. This study aims to comprehensively investigate the relationship between the occurrence of the vibration-induced white finger (VWF) and changes in FSBP and then set the application value of FSBP measurements in the early diagnosis of VWF. METHODS: All samples were judgmental sampling from one factory. Totally 50 patients with VWF were the case group, while 50 without occupational hand-transmitted vibration exposure were the control group. FSBP measurements and epidemiological feature investigations were taken. RESULTS: There were significant reductions in FSBP level and %FSBP index at both 10 °C and 30 °C in fingers reported VWF ( P  < 0.05). The %FSBP abnormal rate of the index, ring and little finger in the VWF group was higher than the control (44.00% vs. 18.00%, 78.00% vs. 26.00%, 64.00% vs. 8.00%). The %FSBP of the ring and little finger had a relatively high application value (area under curve = 0.902, 0.737), while their standard regression coefficients were -0.23 and -0.412. The diagnostic cutoff value of the ring finger was 77.60%, while the sensitivity and specificity were 86.67%. CONCLUSION: FSBP measurements were proven helpful in monitoring and diagnosing VWF prospectively and proved to have great application value in our study. %FSBP of the ring finger was the appropriate diagnostic index in FSBP measurements, while its abnormal value could be set as 80.00%.