Search

A histidine (His)-tag is composed of six His residues and typically exerts little influence on the structure and solubility of expressed recombinant fusion proteins. Purification methods for recombinant proteins containing His-tags are relatively well-established, thus His-tags are widely used in protein recombination technology. We established a one-step enzyme-linked immunosorbent assay (ELISA) for His-tagged recombinant proteins. We analyzed variable heavy and light chains of the anti-His-tag monoclonal antibody 4C9 and used BLAST analyses to determine variable zones in light (VL) and heavy chains (VH). VH, VL, and alkaline phosphatase (ALP) regions were connected via a linker sequence and ligated into the pGEX-4T-1 expression vector. Different recombinant proteins with His tags were used to evaluate and detect ALP-scFv activity. Antigen and anti-His-scFv-ALP concentrations for direct ELISA were optimized using the checkerboard method. ZIKV-NS1, CHIKV-E2, SCRV-N, and other His-tag fusion proteins demonstrated specific reactions with anti-His-scFv-ALP, which were accurate and reproducible when the antigen concentration was 50 µg mL−1 and the antibody concentration was 6.25 µg mL−1. For competitive ELISA, we observed a good linear relationship when coating concentrations of recombinant human anti-Müllerian hormone (hAMH) were between 0.78 and 12.5 µg mL−1. Our direct ELISA method is simple, rapid, and accurate. The scFv antibody can be purified using a prokaryotic expression system, which provides uniform product quality and reduces variations between batches.

Antibiotic resistance (ABR) is a growing public health concern worldwide, and it is now regarded as a critical One Health issue. One Health's interconnected domains contribute to the emergence, evolution, and spread of antibiotic-resistant microorganisms on a local and global scale, which is a significant risk factor for global health. The persistence and spread of resistant microbial species, and the association of determinants at the humananimal-environment interface can alter microbial genomes, resulting in resistant superbugs in various niches. ABR is motivated by a well-established link between three domains: human, animal, and environmental health. As a result, addressing ABR through the One Health approach makes sense. Several countries have implemented national action plans based on the One Health approach to combat antibiotic-resistant microbes, following the Tripartite's Commitment Food and Agriculture Organization (FAO)-World Organization for Animal Health (OIE)-World Health Organization (WHO) guidelines. The ABR has been identified as a global health concern, and efforts are being made to mitigate this global health threat. To summarize, global interdisciplinary and unified approaches based on One Health principles are required to limit the ABR dissemination cycle, raise awareness and education about antibiotic use, and promote policy, advocacy, and antimicrobial stewardship. [ABSTRACT FROM AUTHOR]

Background: Coronaviruses (CoVs) represent a serious threat to human health and have become a major transmissible, endemic, and causative pathogen in humans; they represent a major health concern, given their ability to cause infectious diseases. Bats are natural hosts for diverse viruses. Many transmission events of CoVs and identification of multiple novel CoVs in bats has increased attention towards their capacity to serve as hosts for zoonotic viruses. Results: In this study, 61 bats from Yunnan Province were analyzed, identifying seven CoVs, including three α- and two β-CoVs with full-genome sequences. Among the five identified alpha-CoVs, four belong to the Decacovirus subgenus and one to the Minunacovirus subgenus. Two beta-CoVs were also identified, both belonging to the Sarbecovirus subgenus.The genetic structures revealed similarities to known strains such as HKU10 and SARS-CoV-2, along with novel findings such as the Minunacovirus subgenus CoV YJ3c/f and unique ORF patterns. Our results demonstrated that strain JCC9 has a unique recombination pattern and shows a higher binding affinity to civet and pangolin ACE2 receptors, then the HpJC8xc strain transmits and recombines between hosts (bats), indicating a potential risk of crossing the interspecies barrier and infecting other animals. Conclusions: The CoVs detected in the bats studied in this research exhibit high diversity. Genomic analysis revealed that CoVs in bats undergo frequent recombination events. Furthermore, recombination patterns and evolutionary analyses suggest that alpha-CoVs are more prone to cross-species transmission across different bat families/genera, whereas beta-CoVs demonstrate host specificity and tend to co-evolve with their bat hosts.Our finding suggest that bats, as hosts of CoVs, be constantly monitored to prevent outbreaks of new infections caused by viruses passing across interspecies barriers, and consequently, viral diseases in humans or livestock. [ABSTRACT FROM AUTHOR]

The long-term benefits of direct-acting antiviral (DAA) therapy after achieving sustained virological response (SVR) remain uncertain in the Chinese population. This study evaluates the incidence of hepatocellular carcinoma (HCC), hepatic decompensation, and all-cause mortality among Chinese hepatitis C patients treated with DAAs. We included patients diagnosed since 2011 and followed them until November 1, 2022. The primary outcomes were HCC, hepatic decompensation, and mortality. Multivariable proportional hazards model was used to assess the impact of SVR and cirrhosis status. The cohort consisted of 1272 patients with SVR (92.1%) and 109 without SVR (7.9%), with a median follow-up of 61 months. The incidence of HCC was significantly lower in the SVR group (5.1 per 1000 person-years) compared to the no-SVR group (15.0 per 1000 person-years). Achieving SVR was associated with a significantly reduced risk of HCC (adjusted hazard ratio: 0.32; 95% CI 0.16–0.67). Cirrhosis was linked to an increased risk of developing HCC and hepatic decompensation. These findings highlight the importance of early DAA treatment, particularly for patients with cirrhosis. [ABSTRACT FROM AUTHOR]

Proteus mirabilis, a gram‐negative bacterium, poses a significant public health threat due to its multidrug‐resistant (MDR) characteristics. Here, for the first time, we report the isolation and comprehensive genome analysis of an MDR strain, P. mirabilis KUST‐1312, obtained from migratory birds in Yunnan Province, China. A total of 65 samples, including migratory bird feces, soil, and water from Dianchi Lake, were collected. Standard microbiological techniques were employed to isolate the P. mirabilis KUST‐1312 strain from these samples. Genomic sequencing was conducted using a hybrid assembly strategy, combining Illumina and Oxford nanopore sequencing technologies. Phenotypic testing revealed the MDR nature of P. mirabilis KUST‐1312, displaying resistance to various antibiotics except gentamicin and Cefotaxime. Notably, 15 antimicrobial resistance genes (ARGs), including aph(3′)‐Ia, cat, tet(J), bleO, dfrA12, aadA2, AAC(3)‐IId, bla-TEM-1B, erm(42),aph(6)‐Id, blaPER-1, sul2, aph(3′')‐Ib(2copies), and aph(3′)‐VIb, were identified on a single chromosome. These 15 ARGs were dispersed along three MDR regions, and the boundaries of these regions were consistently flanked by copies of insertion sequences and also contained other genetic elements. Phylogenetic analysis revealed the close relation of P. mirabilis KUST‐1312 with environmental and clinical isolates reported from other continents rather than with Asian isolates. In conclusion, this study reports the first‐ever isolation of an MDR P. mirabilis KUST‐1312 strain from migratory birds globally, particularly in China. There is a need to explore further its prevalence in detail in various ecological niches, including migratory birds. [ABSTRACT FROM AUTHOR]

Paramyxoviridae is one of the most well known and largest virus families, including some animal and human pathogens, such as the Hendra, Nipah, and Rinderpest viruses, with a high potential for the emergence of human diseases. Based on recent phylogenetic analyses, two new genera (Narmovirus and Jeilongvirus) have been described. The newly recognized genus Jeilongvirus has rapidly increased in number and has grown to 15 species from 7 a few years ago. However, little is known about the diversity, host range, or evolution of Jeilongvirus. As a well-known host reservoir for many pathogens, rodents have always been the focus for characterizing their pathogenic potential. In this study, we isolated a Tailam virus strain (RN-JH-YN-2022-1) belonging to the genus Jeilongvirus from Rattus norvegicus in Yunnan Province, China. The virus presented a near-complete genome (19,046 nucleotides). Similar to other members of the genus Jeilongvirus, the genome of RN-JH-YN-2022-1 contains eight basic genes (3′-N-P/V/C-M-F-SH-TM-G-L-5′) with 88.88% sequence identity to Tailam virus (TL8K). Additionally, we discuss the pattern of genus Jeilongvirus diversity and the possible route of spread of the Tailam virus, which could provide new clues into the host range, virus diversity, and geographical distribution of the genus Jeilongvirus. [ABSTRACT FROM AUTHOR]

Hemorrhagic fever with renal syndrome caused by hantaviruses has long been a serious public health issue in Yunnan Province. Hantaviruses exhibit a high extent of biodiversity in their natural hosts, particularly in mammalian hosts. This study was conducted to screen for hantaviruses in bats and rodents in Yunnan Province and elucidate their genetic characteristics and possible zoonotic disease risk. Hantaviruses were detected in 202 bats and 372 rodents with the positive rates 27.49% and 1.25% respectively. A novel lineage (named Lineage 10) of the Seoul virus (SEOV) from rodents and the geographic clustering of hantavirus in bats were identified using phylogenetic analyses of the full-length M- and S-segments. Our study suggest a high cross-species transmissibility of hantaviruses in bats and existence of a new lineage of SEOV in rodents differing significantly from other SEOVs. These results provide data to support the prevention and control of hantavirus-associated diseases in Yunnan Province. Author summary: Hantavirus is an important pathogen that can cause hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). HFRS has long been a serious public health problem in Yunnan Province. However, the molecular epidemiology and host characteristics of hantavirus in Yunnan Province are still unclear. Therefore, we screened hantaviruses in bats and rodents in selected areas of Yunnan from 2018 to 2022 and found the 10th SEOV lineage in rodents, as well as new geographic clusters of Xuan son virus (XSV) and novel hantavirus in bats. We proposed the possibility of the 10th SEOV lineage in rodents as an ancestral lineage and explained the related host-switching events in bat hantaviruses. These results provide data to reveal a greater risk of zoonotic disease and support the prevention and control of hantavirus-associated diseases and in Yunnan Province. [ABSTRACT FROM AUTHOR]

The genetic diversity of killer cell immunoglobulin‐like receptors (KIRs) and human leukocyte antigen (HLA) genes influences the host's immune response to viral pathogens. This study aims to explore the impact of five single nucleotide polymorphisms (SNPs) in KIR3DL2 and HLA‐A genes on hepatitis C virus (HCV) infection. A total of 2251 individuals were included in the case‐control study. SNPs including KIR3DL2 rs11672983, rs3745902, rs1654644, and HLA‐A rs3869062, rs12202296 were genotyped. By controlling various confounding factors using a modified logistic regression model, as well as incorporating stratified analysis, joint effects analysis, and multidimensional bioinformatics analysis, we analyzed the relationship between SNPs and HCV infection. The logistic regression analysis showed a correlation between KIR3DL2 rs11672983 AA, KIR3DL2 rs3745902 TT, and increased HCV susceptibility (p < 0.01). Stratified analysis indicated that KIR3DL2 rs1654644 and HLA‐A rs3869062 also heightened HCV susceptibility in certain subgroups. A linear trend of rising HCV infection rates was observed when combining KIR3DL2 rs11672983 AA and KIR3DL2 rs3745902 TT (ptrend = 0.007). Bioinformatics analysis suggested these SNPs' regulatory potential and their role in altering messenger RNA secondary structure, implying their functional relevance in HCV susceptibility. Our findings indicate that KIR3DL2 rs11672983 AA and KIR3DL2 rs3745902 TT are significantly associated with increased susceptibility to HCV infection. [ABSTRACT FROM AUTHOR]

The question of whether patients in the immune‐tolerant (IT) phase of chronic hepatitis B virus (HBV) infection should undergo antiviral therapy and determine the optimal regimen remains unclear. A comprehensive search of PubMed, Embase, MEDLINE, Cochrane Library, and Wanfang Data from inception to 5 December 2023, was conducted. Studies reporting on key outcomes such as HBV DNA undetectability, HBeAg loss or seroconversion, HBsAg loss or seroconversion, and hepatocellular carcinoma (HCC) incidence in patients in the IT phase of chronic HBV infection were included. In total, 23 studies were incorporated. Approximately 4% of patients in the IT phase achieved spontaneous HBeAg loss over 48 weeks of follow‐up. Antiviral therapy demonstrated a favourable impact on HBV DNA negative conversion (Children: risk ratios [RR] = 6.83, 95% CI: 2.90–16.05; Adults: RR = 25.84, 95% CI: 6.47–103.31) and HBsAg loss rates (Children: RR = 9.49, 95% CI: 1.74–51.76; Adults: RR = 7.35, 95% CI: 1.41–38.27) for patients in the IT phase. Subgroup analysis revealed that in adult patients in the IT phase, interferon plus nucleos(t)ide analogues (NA)‐treated patients exhibited a higher pooled rate of HBsAg loss or seroconversion than those treated with NA monotherapy (9% vs. 0%). Additionally, the pooled annual HCC incidence for patients in the IT phase was 3.03 cases per 1000 person‐years (95% CI: 0.99–5.88). Adult patients in the IT phase had a significantly lower HCC incidence risk than HBeAg‐positive indeterminate phase patients (RR = 0.46, 95% CI: 0.32–0.66), with no significant differences observed between IT and immune‐active phases. Presently, there is insufficient evidence solely based on reducing the risk of HCC incidence, to recommend treating patients in the IT phase of chronic HBV infection. However, both adult and paediatric patients in the IT phase responded well to antiviral therapy, showing favourable rates of HBsAg loss or seroconversion. [ABSTRACT FROM AUTHOR]

Wildlife serve as potential microbial reservoirs, accounting for approximately 70% of emerging infectious diseases. Crimean–Congo hemorrhagic fever virus (CCHFV), which causes Crimean–Congo hemorrhagic fever (CCHF) in humans, is a highly pathogenic tick-borne virus prevalent in several parts of Asia, Africa, and Europe with high case fatality rates. Several CCHFV cases have been reported in Asia, the Middle East, Africa, and Southern and Eastern Europe. The disease is endemic in several parts of western China, particularly Xinjiang. Ticks of the genus Hyalomma have been identified as a principal vector and reservoir for CCHFV, although other tick species may also have a crucial role in maintaining CCHFV in endemic regions. On infection, CCHF begins as a nonspecific febrile illness that can progress to severe hemorrhagic manifestations with a higher case fatality due to the unavailability of vaccines or other therapeutic agents. In this study, we collected tissue samples from a wild dead Chinese serow (Capricornis milneedwardsii) and three Naemorhedus griseuses from Deqin County, Tibetan Autonomous Prefecture, Yunnan, China, to investigate for contagious viruses that could be transmitted to humans. We identified a novel CCHFV strain, YNDQL-415G, in the liver tissue of a dead C. milneedwardsii. We performed nucleotide and amino acid sequence homology on the full-length viral genome. The results revealed significant homology between the viral S segment to that of the Africa1 strain, while the M and L segments showed similarity with the Asia CCHFV strain, indicating potential gene reassortment in the YNDQL-415G strain. The genetic characterization of a novel CCHFV strain from a dead C. milneedwardsii raises concerns about the possibility of a new zoonotic infection. A regular survey program is recommended to track the distribution of wild animals as well as the viruses they may transmit to humans and other domestic mammals in the region. [ABSTRACT FROM AUTHOR]

Antibiotic resistance (ABR) is a growing public health concern worldwide, and it is now regarded as a critical One Health issue. One Health’s interconnected domains contribute to the emergence, evolution, and spread of antibiotic-resistant microorganisms on a local and global scale, which is a significant risk factor for global health. The persistence and spread of resistant microbial species, and the association of determinants at the human-animal-environment interface can alter microbial genomes, resulting in resistant superbugs in various niches. ABR is motivated by a well-established link between three domains: human, animal, and environmental health. As a result, addressing ABR through the One Health approach makes sense. Several countries have implemented national action plans based on the One Health approach to combat antibiotic-resistant microbes, following the Tripartite’s Commitment Food and Agriculture Organization (FAO)-World Organization for Animal Health (OIE)-World Health Organization (WHO) guidelines. The ABR has been identified as a global health concern, and efforts are being made to mitigate this global health threat. To summarize, global interdisciplinary and unified approaches based on One Health principles are required to limit the ABR dissemination cycle, raise awareness and education about antibiotic use, and promote policy, advocacy, and antimicrobial stewardship.

This study was designed to explore baseline data about the prevalence and distribution of human papillomavirus (HPV) genotypes among Chinese women who had cervical intraepithelial lesions and cervical cancer. A total of 511 patients were recruited, and biopsy samples were collected from these patients. Polymerase chain reaction was used to detect HPV-positive samples, and the HPV GenoArray kit was used for genotyping. A total of 23 genotypes were detected, including 13 that were high risk-HPV (HR-HPV), 3 that were potential high risk-HPV (PHR-HPV) and 7 that were low risk-HPV (LR-HPV). The prevalence rates of HPV infection in Han women diagnosed with cervical intraepithelial lesions (CIN) 1, 2, and 3 and squamous cell carcinoma (SCC) were 98.30%, 97.56, 100% and 90%, respectively. The HPV-positive cases in women of other ethnicities diagnosed with CIN1, CIN2, and CIN3 and SCC were 95%, 90.91%, 88.23% and 83.33%, respectively. The most frequent genotypes in both ethnic groups were HPV-16, 52, and 58. LR-HPV was detected in SCC lesions in the non-Han ethnic group. In the Han ethnic group, the LR-HPV genotype was mostly restricted to CIN1 lesions. Furthermore, we found a high prevalence of PHR-HPV-81 in SCC lesions among Han women. Ethnic background, smoking, sex at an early age, unprotected sex, use of contraceptives, and the withdrawal method were found to be significantly associated with HPV infection. In conclusion, this study explores epidemiological data regarding the prevalence of HPV and the genotype distribution in patients with SCC and CIN lesions in Yunnan Province, China. Keywords: Human papillomavirus, Prevalence, Genotype, Han, Ethnic, Yunnan

Hepatitis B virus (HBV) infection is a global public health problem that is closely related to liver cirrhosis and hepatocellular carcinoma (HCC). The prevalence of acute and chronic HBV infection, liver cirrhosis, and HCC has significantly decreased as a result of the introduction of universal HBV vaccination programs. The first hepatitis B vaccine approved was developed by purifying the hepatitis B surface antigen (HBsAg) from the plasma of asymptomatic HBsAg carriers. Subsequently, recombinant DNA technology led to the development of the recombinant hepatitis B vaccine. Although there are already several licensed vaccines available for HBV infection, continuous research is essential to develop even more effective vaccines. Prophylactic hepatitis B vaccination has been important in the prevention of hepatitis B because it has effectively produced protective immunity against hepatitis B viral infection. Prophylactic vaccines only need to provoke neutralizing antibodies directed against the HBV envelop proteins, whereas therapeutic vaccines are most likely needed to induce a comprehensive T cell response and thus, should include other HBV antigens, such as HBV core and polymerase. The existing vaccines have proven to be highly effective in preventing HBV infection, but ongoing research aims to improve their efficacy, duration of protection, and accessibility. The routine administration of the HBV vaccine is safe and well-tolerated worldwide. The purpose of this type of immunization is to trigger an immunological response in the host, which will halt HBV replication. The clinical efficacy and safety of the HBV vaccine are affected by a number of immunological and clinical factors. However, this success is now in jeopardy due to the breakthrough infections caused by HBV variants with mutations in the S gene, high viral loads, and virus-induced immunosuppression. In this review, we describe various types of available HBV vaccines, along with the recent progress in the ongoing battle to develop new vaccines against HBV. [ABSTRACT FROM AUTHOR]