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The possible contamination routes, environmental adaptation, and genetic basis of Cronobacter spp. in infant and follow-up formula production factories and retailed products in mainland China have been determined by laboratory studies and whole-genome comparative analysis in a 7-year nationwide continuous surveillance spanning from 2012 to 2018. The 2-year continuous multicenter surveillance of the production process (conducted in 2013 and 2014) revealed that the source of Cronobacter spp. in the dry-blending process was the raw dry ingredients and manufacturing environment (particularly in the vibro sieve and vacuum cleaner), while in the combined process, the main contamination source was identified as the packing room. It is important to note that, according to the contamination control knowledge obtained from the production process surveillance, the contamination rate of retail powdered infant formula (PIF) and follow-up formula (FUF) products in China decreased significantly from 2016 onward, after improving the hygiene management practices in factories. The prevalence of Cronobacter spp. in retailed PIF and FUF in China in 2018 was dramatically reduced from 1.55 % (61/3925, in 2012) to an average as low as 0.17 % (13/7655 in 2018). Phenotype determination and genomic analysis were performed on a total of 90 Cronobacter spp. isolates obtained from the surveillance. Of the 90 isolates, only two showed resistance to either cefazolin or cefoxitin. The multilocus sequence typing results revealed that C. sakazakii sequence type 1 (ST1), ST37, and C. malonaticus ST7 were the dominant sequence types (STs) collected from the production factories, while C. sakazakii ST1, ST4, ST64, and ST8 were the main STs detected in the retailed PIF and FUF nationwide. One C. sakazakii ST4 isolate (1.1 %, 1/90) had strong biofilm-forming ability and 13 isolates (14.4 %, 13/90) had weak biofilm-forming ability. Genomic analysis revealed that Cronobacter spp. have a relatively stable core-genome and an increasing pan-genome size. Plasmid IncFIB (pCTU3) was prevalent in this genus and some contained 14 antibacterial biocide- and metal-resistance genes (BMRGs) including copper, silver, and arsenic resistant genes. Plasmid IncN_1 was predicted to contain 6 ARGs. This is the first time that a multi-drug resistance IncN_1 type plasmid has been reported in Cronobacter spp. Genomic variations with respect to BMRGs, virulence genes, antimicrobial resistance genes (ARGs), and genes involved in biofilm formation were observed among strains of this genus. There were apparent differences in copies of bcsG and flgJ between the biofilm-forming group and non-biofilm-forming group, indicating that these two genes play key roles in biofilm formation. The findings of this study have improved our understanding of the contamination characteristics and genetic basis of Cronobacter spp. in PIF and FUF and their production environment in China and provide important guidance to reduce contamination with this pathogen during the production of PIF and FUF.
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Cronobacter , Fórmulas Infantis , China , Cronobacter/genética , Microbiologia de Alimentos , Contaminação de Alimentos/análise , Humanos , LactenteRESUMO
The pituitary is the central endocrine gland with effects on metabolic dysfunction-associated steatotic liver disease (MASLD). However, it is not clear whether the pituitary responds to free fatty acid (FFA) toxicity, thus dysregulating hepatic lipid metabolism. Here, we demonstrate that decreased prolactin (PRL) levels are involved in the association between FFA and MASLD based on a liver biospecimen-based cohort. Moreover, overloaded FFAs decrease serum PRL levels, thus promoting liver steatosis in mice with both dynamic diet intervention and stereotactic pituitary FFA injection. Mechanistic studies show that excessive FFA sensing in pituitary lactotrophs inhibits the synthesis and secretion of PRL in a cell-autonomous manner. Notably, inhibiting excessive lipid uptake using pituitary stereotaxic virus injection or a specific drug delivery system effectively ameliorates hepatic lipid accumulation by improving PRL levels. Targeted inhibition of pituitary FFA sensing may be a potential therapeutic target for liver steatosis.
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Ácidos Graxos não Esterificados , Fígado Gorduroso , Lactotrofos , Prolactina , Animais , Prolactina/metabolismo , Prolactina/sangue , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Camundongos , Lactotrofos/metabolismo , Lactotrofos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Humanos , Masculino , Metabolismo dos Lipídeos , Fígado/metabolismoRESUMO
Purpose: This study conducted an phenotypic and whole-genome sequencing analysis with Klebsiella aerogenes to elucidate its clinical epidemiological characteristics, antimicrobial resistance (AMR) phenotype, biofilm formation ability and hemolytic activity testing, AMR genes and phylogenetic relationships, so as to provide a further understanding of the intra-hospital strain transmission. Methods: Samples were collected from a hospital in Beijing between 2020 and 2022. All strains underwent bacterial identification, antimicrobial susceptibility testing (AST) using the VITEK-2 compact system. Biofilm formation ability and hemolytic activity were tested. Second-generation sequencing was applied to all strains, with those carrying the bla KPC gene were selected for third-generation sequencing. Whole-genome analysis identified resistance genes, plasmid types, MLST typing, and phylogenetic relationships. Plasmids were assembled to detect plasmid structures and AMR gene location. Results: Among the 42 K. aerogenes isolates, 21 were carbapenem-resistant K. aerogenes (CRKA). All strains exhibited strong biofilm formation and no hemolytic activity. Most were sourced from sputum (83.3%). CRKA demonstrated extensive resistance to antibiotics, particularly ß-lactamase inhibitors and Cefotetan. This resistance pattern was closely associated with the presence of an IncFII(pHN7A8) plasmid, which carried multiple resistance genes, including bla KPC-2, bla CTX-M-65, bla TEM-1, rmtB and a large number of mobile elements. The majority of CRKA strains clustered within the same branch of the phylogenetic tree, exhibiting minimal single nucleotide polymorphism (0-13 SNPs) differences, and they shared the same sequence type (ST292), resistance genes, and plasmids, originating from different departments, suggesting clonal transmission among the hospital. Conclusion: Our research reveals that the clonal transmission of CRKA occurs across various departments within the hospital. The widespread resistance observed in CRKA, attributed to the presence of bla KPC and ESBLs genes, underscores the need for heightened vigilance to prevent the further dissemination of CRKA within the hospital and, potentially, throughout the wider community.
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Bitter taste receptors (TAS2Rs) Tas2r108 gene possesses a high abundance in mouse kidney; however, the biological functions of Tas2r108 encoded receptor TAS2Rs member 4 (TAS2R4) are still unknown. In the present study, we found that mouse TAS2R4 (mTAS2R4) signaling was inactivated in chronic high glucose-stimulated mouse podocyte cell line MPC, evidenced by the decreased protein expressions of mTAS2R4 and phospholipase C ß2 (PLCß2), a key downstream molecule of mTAS2R4 signaling. Nonetheless, agonism of mTAS2R4 by quinine recovered mTAS2R4 and PLCß2 levels, and increased podocyte cell viability as well as protein expressions of ZO-1 and nephrin, biomarkers of podocyte slit diaphragm, in high glucose-cultured MPC cells. However, blockage of mTAS2R4 signaling with mTAS2R4 blockers γ-aminobutyric acid and abscisic acid, a Gßγ inhibitor Gallein, or a PLCß2 inhibitor U73122 all abolished the effects of quinine on NLRP3 inflammasome and p-NF-κB p65 as well as the functional podocyte proteins in MPC cells in a high glucose condition. Furthermore, knockdown of mTAS2R4 with lentivirus-carrying Tas2r108 shRNA also ablated the effect of quinine on the key molecules of the above inflammatory signalings and podocyte functions in high glucose-cultured MPC cells. In summary, we demonstrated that activation of TAS2R4 signaling alleviated the podocyte injury caused by chronic high glucose, and inhibition of NF-κB p65 and NLRP3 inflammasome mediated the protective effects of TAS2R4 activation on podocytes. Moreover, activation of TAS2R4 signaling could be an important strategy for prevention and treatment of diabetic kidney disease.
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Glucose , Podócitos , Receptores Acoplados a Proteínas G , Transdução de Sinais , Podócitos/metabolismo , Podócitos/efeitos dos fármacos , Podócitos/patologia , Animais , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Glucose/toxicidade , Glucose/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Linhagem CelularRESUMO
BACKGROUND: CRISPR-Cas9 technology has advanced in vivo gene therapy for disorders like hemophilia A, notably through the successful targeted incorporation of the F8 gene into the Alb locus in hepatocytes, effectively curing this disorder in mice. However, thoroughly evaluating the safety and specificity of this therapy is essential. Our study introduces a novel methodology to analyze complex insertion sequences at the on-target edited locus, utilizing barcoded long-range PCR, CRISPR RNP-mediated deletion of unedited alleles, magnetic bead-based long amplicon enrichment, and nanopore sequencing. RESULTS: We identified the expected F8 insertions and various fragment combinations resulting from the in vivo linearization of the double-cut plasmid donor. Notably, our research is the first to document insertions exceeding ten kbp. We also found that a small proportion of these insertions were derived from sources other than donor plasmids, including Cas9-sgRNA plasmids, genomic DNA fragments, and LINE-1 elements. CONCLUSIONS: Our study presents a robust method for analyzing the complexity of on-target editing, particularly for in vivo long insertions, where donor template integration can be challenging. This work offers a new tool for quality control in gene editing outcomes and underscores the importance of detailed characterization of edited genomic sequences. Our findings have significant implications for enhancing the safety and effectiveness of CRISPR-Cas9 gene therapy in treating various disorders, including hemophilia A.
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Hemofilia A , Sequenciamento por Nanoporos , Camundongos , Animais , Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Hemofilia A/genética , Hemofilia A/terapia , Edição de Genes/métodos , DNARESUMO
Background: The escalating resistance of Klebsiella pneumoniae, a prevalent pathogen in healthcare settings, especially its carbapenem-resistant K. pneumoniae (CRKP), to a wide array of antibiotics, notably ß-lactams, constitutes a formidable challenge for healthcare and global public health management. Methods: This research compared the resistance phenotypes and genomic profiles of CRKP and Non-CRKP isolates in a Beijing hospital, focusing on high-risk blaKPC-2 gene-bearing CRKP clones and the structure of mobile genetic elements facilitating their spread across hospital departments. Forty K. pneumoniae isolates were collected from various departments of the hospital and subjected to antimicrobial susceptibility testing and whole-genome sequencing to analyze their resistance phenotypes and genomic features. Results: The study revealed that among the 31 CRKP isolates, ST11 is the most common sequence type, with K47 and OL101 being the dominant capsule types, primarily observed in the respiratory department. In terms of antimicrobial susceptibility: 87.5% of the isolates exhibited multidrug resistance (MDR), with a high resistance rate of 30% against tigecycline. All CRKP isolates demonstrated resistance to multiple drug classes (≥5 CLSI classes). Non-CRKP isolates also showed high resistance rates to minocycline and doxycycline (77.8%). the ST11-KL47-OL101 type emerged as the predominant clone among the CRKP isolates carrying the blaKPC-2 gene. This dominance appears to be mediated by the pKpnR03_2 plasmid, which harbors not only blaKPC-2 and rmtb but also gene clusters pertinent to iron transport and arsenic resistance. These isolates, clustering in the C3 clade of the phylogenetic tree, exhibited minor genetic variations and close evolutionary relationships, suggesting a plasmid-driven spread across various hospital departments. Conclusion: In summary, our study highlights the extensive spread of antibiotic-resistant K. pneumoniae across various departments in our hospital, with a particular emphasis on the dominant clonal proliferation of the ST11-KL47-OL101 CRKP strain. This finding underscores the significant role of plasmid-mediated gene transfer in the evolution and dissemination of resistant strains within hospital environments. The study emphasizes the necessity for ongoing surveillance of antibiotic resistance and genomic analysis in hospital settings to effectively monitor and manage these challenges.
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Human astrovirus (HAstV) is a single-stranded, positive-sense RNA virus and is the leading cause of viral gastroenteritis. However, despite its prevalence, astroviruses still remain one of the least studied enteroviruses. In this study, we sequenced 11 classical astrovirus strains from clinical samples collected in Shenzhen, China from 2016 to 2019, analyzed their genetic characteristics, and deposited them into GenBank. We conducted phylogenetic analysis using IQ-TREE software, with references to astrovirus sequences worldwide. The phylogeographic analysis was performed using the Bayesian Evolutionary Analysis Sampling Trees program, through Bayesian Markov Chain Monte Carlo sampling. We also conducted recombination analysis with the Recombination Detection Program. The newly sequenced strains were categorized as HAstV genotype 1, which is the predominant genotype in Shenzhen. Phylogeographic reconstruction indicated that HAstV-1 may have migrated from the United States to China, followed by frequent transmission between China and Japan. The recombination analysis revealed recombination events within and across genotypes, and identified a recombination-prone region that produced relatively uniform recombination breakpoints and fragment lengths. The genetic analysis of HAstV strains in Shenzhen addresses the current lack of astrovirus data in the region of Shenzhen and provides key insights to the evolution and transmission of astroviruses worldwide. These findings highlight the importance of improving surveillance of astroviruses.
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Infecções por Astroviridae , Astroviridae , Mamastrovirus , Humanos , Filogenia , Teorema de Bayes , Infecções por Astroviridae/epidemiologia , RNA Viral/genética , Fezes , Astroviridae/genética , Mamastrovirus/genética , China/epidemiologia , GenótipoRESUMO
COVID-19 has posed unprecedented challenges to global public health since its outbreak. The Qing-Fei-Pai-Du decoction (QFPDD), a Chinese herbal formula, is widely used in China to treat COVID-19. It exerts an impressive therapeutic effect by inhibiting the progression from mild to critical disease in the clinic. However, the underlying mechanisms remain obscure. Both SARS-CoV-2 and influenza viruses elicit similar pathological processes. Their severe manifestations, such as acute respiratory distress syndrome (ARDS), multiple organ failure (MOF), and viral sepsis, are correlated with the cytokine storm. During flu infection, QFPDD reduced the lung indexes and downregulated the expressions of MCP-1, TNF-[Formula: see text], IL-6, and IL-1[Formula: see text] in broncho-alveolar lavage fluid (BALF), lungs, or serum samples. The infiltration of neutrophils and inflammatory monocytes in lungs was decreased dramatically, and lung injury was ameliorated in QFPDD-treated flu mice. In addition, QFPDD also inhibited the polarization of M1 macrophages and downregulated the expressions of IL-6, TNF-[Formula: see text], MIP-2, MCP-1, and IP-10, while also upregulating the IL-10 expression. The phosphorylated TAK1, IKK[Formula: see text]/[Formula: see text], and I[Formula: see text]B[Formula: see text] and the subsequent translocation of phosphorylated p65 into the nuclei were decreased by QFPDD. These findings indicated that QFPDD reduces the intensity of the cytokine storm by inhibiting the NF-[Formula: see text]B signaling pathway during severe viral infections, thereby providing theoretical and experimental support for its clinical application in respiratory viral infections.
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COVID-19 , Interleucina-6 , Animais , Camundongos , Interleucina-6/metabolismo , COVID-19/metabolismo , SARS-CoV-2 , Neutrófilos/metabolismo , Síndrome da Liberação de Citocina , Macrófagos/metabolismo , NF-kappa B/metabolismoRESUMO
INTRODUCTION: Despite the advances made in cancer treatment in the past decades, therapeutic efficacy is still quite challenging, partially due to the emergence of multidrug resistance (MDR). It is crucial to decipher the underlying mechanisms of resistance in order to develop new therapeutic strategies for cancer patients. Previous studies have shown that activation of nuclear factor-κB (NF-κB) plays key roles in various cellular processes including proliferation, anti-apoptosis, metastasis, invasion, and chemoresistance. AREAS COVERED: In this review, we conduct an integrated analysis of the evidence suggesting the vital roles of the NF-κB signaling pathway in MDR during chemotherapy, immunotherapy, endocrine, and targeted therapy. A literature search was performed on NF-κB and drug resistance in PubMed up to February 2023. EXPERT OPINION: This review summarizes that the NF-κB signaling pathway exhibits a crucial role in enhancing drug resistance in chemotherapy, immunotherapy, endocrine, and targeted therapy. The application of combination therapy with existing antineoplastic drugs and a safe NF-κB inhibitor could become a promising strategy in cancer treatment. A better understanding of the pathway and mechanisms of drug resistance may help exploit safer and more effective NF-κB-targeting agents for clinical use in the future.
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Antineoplásicos , Neoplasias , Humanos , NF-kappa B/metabolismo , Transdução de Sinais , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular TumoralRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern challenge the efficacy of approved vaccines, emphasizing the need for updated spike antigens. Here, we use an evolutionary-based design aimed at boosting protein expression levels of S-2P and improving immunogenic outcomes in mice. Thirty-six prototype antigens were generated in silico and 15 were produced for biochemical analysis. S2D14, which contains 20 computationally designed mutations within the S2 domain and a rationally engineered D614G mutation in the SD2 domain, has an ~11-fold increase in protein yield and retains RBD antigenicity. Cryo-electron microscopy structures reveal a mixture of populations in various RBD conformational states. Vaccination of mice with adjuvanted S2D14 elicited higher cross-neutralizing antibody titers than adjuvanted S-2P against the SARS-CoV-2 Wuhan strain and four variants of concern. S2D14 may be a useful scaffold or tool for the design of future coronavirus vaccines, and the approaches used for the design of S2D14 may be broadly applicable to streamline vaccine discovery.
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COVID-19 , SARS-CoV-2 , Animais , Camundongos , Anticorpos Antivirais , Testes de Neutralização , Microscopia CrioeletrônicaRESUMO
We aimed to summarise current evidence on different antidiabetic drugs to delay cognitive impairment, including mild cognitive impairment, dementia, Alzheimer's disease (AD) and vascular dementia, among subjects with type 2 diabetes mellitus (T2DM). Medline, Cochrane and Embase databases were searched from inception to 31 July 2022. Two investigators independently reviewed and screened trials comparing antidiabetic drugs with no antidiabetic drugs, placebo, or other active antidiabetic drugs on cognitive outcomes in T2DM. Data were analysed using meta-analysis and network meta-analysis. Twenty-seven studies met the inclusion criteria, including 3 randomised controlled trials, 19 cohort studies and 5 case-control studies. Compared with non-user, SGLT-2i (OR 0.41 [95% CI 0.22-0.76]), GLP-1RA (OR 0.34 [95% CI 0.14-0.85]), thiazolidinedione (OR 0.60 [95% CI 0.51-0.69]), and DPP-4i (OR 0.78 [95% CI 0.61-0.99]) users had a decreased risk of dementia, whereas sulfonylurea (OR 1.43 [95% CI 1.11-1.82]) increased dementia risk. Network meta-analysis showed that SGLT-2i was most likely to rank best (SUCRA = 94.4%), GLP-1 RA second best (SUCRA = 92.7%), thiazolidinedione third best (SUCRA = 74.7%) and DPP-4i fourth best (SUCRA = 54.9%), while sulfonylurea second worst (SUCRA = 20.0%) for decreasing dementia outcomes, by synthesising evidence from direct and indirect comparisons of multiple intervention. Evidence suggests the effects of SGLT-2i ≈ GLP-1 RAs > thiazolidinedione > DPP-4i for delaying cognitive impairment, dementia and AD outcomes, whereas sulfonylurea was associated with the highest risk. These findings provide evidence for evaluating the optional treatment for clinical practice. PROSPERO REGISTRATION: Registration no. CRD42022347280.
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Demência , Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Tiazolidinedionas , Humanos , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Metanálise em Rede , Compostos de Sulfonilureia/uso terapêutico , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Demência/epidemiologia , Demência/complicações , Tiazolidinedionas/uso terapêutico , Cognição , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1RESUMO
In the past decade, camelid nanobodies have been developed for multiple applications, including immuno-imaging, cancer immunotherapy, and antiviral therapeutics. Despite the prevalence of these approaches, nanobodies have rarely been used to assess the potency of vaccine antigen candidates, which are primarily based on mAb binding approaches. In this work, we demonstrate that a nanobody-based ELISA method is suitable for characterization of a leading respiratory syncytial virus (RSV) vaccine candidate, RSVPreF3. This nanobody, F-VHH-L66, compares similarly with AM14, an antibody well-known to be specific for the prefusion form of the RSV surface fusion glycoprotein, RSV F. ELISA assays based on F-VHH-L66 were specific for the trimeric, prefusion form of RSV F, the antigen conformation that best generates neutralizing antibodies. Additionally, the F-VHH-L66-based ELISA proved accurate, linear, and stability-indicating. Statistical analysis of 65 independent F-VHH-L66-based ELISA experiments indicated assay performance similar to that of ELISA assays based on AM14. Moreover, the binding kinetics of F-VHH-L66 to RSVPreF3 are comparable to those of AM14 when measured by surface plasmon resonance (SPR). Finally, F-VHH-L66 neutralized RSV(A) with similar efficacy as AM14; this bioactivity data further supports its use as an alternative to AM14 for pre-fusion specific structural characterization of RSVPreF3.
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Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Vírus Sincicial Respiratório Humano , Anticorpos de Domínio Único , Humanos , Anticorpos Antivirais , Anticorpos Neutralizantes , Antivirais , Proteínas Virais de Fusão , Infecções por Vírus Respiratório Sincicial/prevenção & controleRESUMO
Persistent asymptomatic (PA) SARS-CoV-2 infections have been identified. The immune responses in these patients are unclear, and the development of effective treatments for these patients is needed. Here, we report a cohort of 23 PA cases carrying viral RNA for up to 191 days. PA cases displayed low levels of inflammatory and interferon response, weak antibody response, diminished circulating follicular helper T cells (cTfh), and inadequate specific CD4+ and CD8+ T-cell responses during infection, which is distinct from symptomatic infections and resembling impaired immune activation. Administration of a single dose of Ad5-nCoV vaccine to 10 of these PA cases elicited rapid and robust antibody responses as well as coordinated B-cell and cTfh responses, resulting in successful viral clearance. Vaccine-induced antibodies were able to neutralize various variants of concern and persisted for over 6 months, indicating long-term protection. Therefore, our study provides an insight into the immune status of PA infections and highlights vaccination as a potential treatment for prolonged SARS-CoV-2 infections.
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COVID-19 , Humanos , SARS-CoV-2 , Infecções Assintomáticas , Anticorpos AntiviraisRESUMO
Human adenoviruses (HAdVs) can cause acute respiratory diseases (ARDs) worldwide, and HAdV-55 is a reemergent pathogen in recent years. In the study, we investigated an outbreak of ARD at a school due to HAdV-55 in Beijing, China, during the early outbreak of coronavirus disease 2019 (COVID-19). The epidemic prevention team was dispatched to the school to collect epidemiologic data and nasopharyngeal samples. Then, real-time reverse transcription polymerase chain reaction (PCR) and multiplex PCR assays were used to detect severe acute respiratory syndrome coronavirus 2 and other respiratory pathogens, respectively. One representative HAdV-55 isolate was selected and submitted for whole-genome sequencing using a MiSeq system and the whole-genome phylogenetic tree was conducted based on the maximum likelihood method. The outbreak lasted from January 27 to February 6, 2020, and 108 students developed fever, among whom 60 (55.56%) cases were diagnosed with HAdV-55 infection in the laboratory using real-time PCR and 56 cases were hospitalized. All the confirmed cases had a fever and 11 cases (18.33%) presented with a fever above 39°C. Other main clinical symptoms included sore throat (43.33%) and headache (43.33%). We obtained and assembled the full genome of one isolate, BJ-446, with 34 761 nucleotides in length. HAdV-55 isolate BJ-446 was 99.85% identical to strain QS-DLL, which was the first HAdV-55 strain in China isolated from an ARD outbreak in Shanxi in 2006. One and four amino acid mutations were observed in the hexon gene and the coding region of L2 pV 40.1 kDa protein, respectively. We identified the first HAdV-55 infection associated with the ARD outbreak in Beijing since the emergence of COVID-19. The study suggests that improved surveillance of HAdV is needed, although COVID-19 is still prevalent in the world.
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Infecções por Adenovirus Humanos , Adenovírus Humanos , COVID-19 , Infecções Respiratórias , Infecções por Adenovirus Humanos/epidemiologia , Aminoácidos , Pequim/epidemiologia , COVID-19/epidemiologia , China/epidemiologia , Surtos de Doenças , Febre/epidemiologia , Humanos , Nucleotídeos , Filogenia , Infecções Respiratórias/epidemiologiaRESUMO
[This corrects the article DOI: 10.3389/fmicb.2021.779749.].
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Salmonella contamination of eggs and egg shells has been identified as a public health problem worldwide. Here, we reported an outbreak of severe gastrointestinal symptoms caused by Salmonella enterica serovar Enteritidis (S. enteritidis) in China. We evaluated the outbreak by using epidemiological surveys, routine laboratory testing methods, and whole genome sequencing (WGS). This outbreak occurred in a canteen in Beijing, during March 9-11, 2021, 225 of the 324 diners who have eaten at the canteen showed gastrointestinal symptoms. The outbreak had characteristical epidemiological and clinical features. It caused a very high attack rate (69.4%) in a short incubation time. All patients developed diarrhea and high fever, accompanied by abdominal pain (62.3%), nausea (50.4%), and vomiting (62.7%). The average frequency of diarrhea was 12.4 times/day, and the highest frequency of diarrhea was as high as 50 times/day. The average fever temperature was 39.4°C, and the highest fever temperature was 42°C. Twenty strains of S. enteritidis were recovered, including 19 from the patients samples, and one from remained egg fried rice. Antibiotic susceptibility test showed that the 20 outbreak strains all had the same resistance pattern. PFGE results demonstrated that all 20 strains bore completely identical bands. Phylogenetic analysis based on WGS revealed that all 20 outbreak strains were tightly clustered together. So the pathogenic source of this food poisoning incident may was contaminated egg fried rice. Resistance gene analysis showed that the outbreak strains are all multi-drug resistant strains. Virulence gene analysis indicated that these outbreak strains carried a large number of virulence genes, including 2 types of Salmonella pathogenicity islands (SPI-1 and SPI-2). Other important virulence genes were also carried by the outbreak strains, such as pefABCD, rck and shdA. And the shdA gene was not in other strains located in the same evolutionary branch as the outbreak strain. We speculated that this is a significant reason for the serious symptoms of gastroenteritis in this outbreak. This outbreak caused by S. enteritidis suggested government should strengthen monitoring of the prevalence of outbreak clone strains, and take measures to mitigate the public health threat posed by contaminated eggs.
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Objectives: To data, no patients with obvious epidemiological relationship co-infected with SARS-CoV-2 and other pathogens have been reported. Here, we investigated 10 patients caused by co-infection with SARS-CoV-2 and human adenovirus (HAdV), resulting in third-generation transmission. Materials and Methods: From Jan 15, 2020, we enrolled 10 patients with pneumonia in Hunan Province, China. Epidemiological, clinical, and laboratory investigation results from these patients were analyzed. An epidemiological investigation was performed to assess whether patient infections were linked using conventional methods and metagenomic sequencing. Results: The presence of co-infection with SARS-CoV-2 and HAdV was determined via RT-PCR and metagenomic sequencing. Phylogenetic analysis revealed that SARS-CoV-2 and HAdV genomes clustered together, with similar genetic relationships. The first patient likely became co-infected during meetings or travel in Wuhan. The patient transmitted the virus via dinners and meetings, which resulted in four second-generation cases. Then, a second-generation case transmitted the virus to her family members or relatives via presymptomatic transmission. Conclusions: This study described an example of co-infection with SARS-CoV-2 and HAdV in pneumonia patients, which caused third-generation cases and inter-regional transmission via meetings, household interactions, and dinner parties. We also observed the persistent and presymptomatic transmission of co-infection, which has the potential to make the continued control of the COVID-19 pandemic challenging. Continuous surveillance is needed to monitor the prevalence, infectivity, transmissibility, and pathogenicity of SARS-CoV-2 co-infection with other pathogens to evaluate its real risk.
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BACKGROUND: Chikungunya fever, caused by the Chikungunya virus (CHIKV), has become a major global health concern, causing unexpected large outbreaks in Africa, Asia, Europe, and the Americas. CHIKV is not indigenous to China, and its origin in the country is poorly understood. In particular, there is limited understanding of the recent global spread of CHIKV in the context of the CHIKV epidemic. METHODS: Here we investigated a novel Chikungunya patient who came from Myanmar to China in August, 2019. Direct genome sequencing was performed via combined MinION sequencing and BGISEQ-500 sequencing. A complete CHIKV genome dataset, including 727 CHIKV genomes retrieved from GenBank and the genome sequenced in this study, was constructed. An updated and comprehensive phylogenetic analysis was conducted to understand the virus's origin, evolution, transmission routes and genetic adaptation. RESULTS: All globally distributed CHIKV genomes were divided into West Africa, East/Central/South African and Asian genotypes. The genome sequenced in this study was located in the Indian Ocean lineage, and was closely related to a strain isolated from an Australian patient who returned from Bangladesh in 2017. A comprehensive phylogenetic analysis showed that the Chinese strains mainly originated from the Indian subcontinent and Southeast Asia. Further analyses indicated that the Indian subcontinent and Southeast Asia may act as major hubs for the recent global spread of CHIKV, leading to multiple outbreaks and epidemics. Moreover, we identified 179 distinct sites, including some undescribed sites in the structural and non-structural proteins, which exhibited apparent genetic variations associated with different CHIKV lineages. CONCLUSIONS: Here we report a novel CHIKV isolate from a chikungunya patient who came from Myanmar to China in 2019, and summarize the source and evolution of Chinese CHIKV strains. Our present findings provide a better understanding of the recent global evolution of CHIKV, highlighting the urgent need for strengthened surveillance against viral diversity.
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Febre de Chikungunya , Vírus Chikungunya , Sudeste Asiático/epidemiologia , Austrália , Surtos de Doenças , Humanos , FilogeniaRESUMO
Respiratory syncytial virus (RSV) is the most common cause of acute lower respiratory tract infections resulting in medical intervention and hospitalizations during infancy and early childhood, and vaccination against RSV remains a public health priority. The RSV F glycoprotein is a major target of neutralizing antibodies, and the prefusion stabilized form of F (DS-Cav1) is under investigation as a vaccine antigen. AM14 is a human monoclonal antibody with the exclusive capacity of binding an epitope on prefusion F (PreF), which spans two F protomers. The quality of recognizing a trimer-specific epitope makes AM14 valuable for probing PreF-based immunogen conformation and functionality during vaccine production. Currently, only a low-resolution (5.5 Å) X-ray structure is available of the PreF-AM14 complex, revealing few reliable details of the interface. Here, we perform complementary structural studies using X-ray crystallography and cryo-electron microscopy (cryo-EM) to provide improved resolution structures at 3.6 Å and 3.4 Å resolutions, respectively. Both X-ray and cryo-EM structures provide clear side-chain densities, which allow for accurate mapping of the AM14 epitope on DS-Cav1. The structures help rationalize the molecular basis for AM14 loss of binding to RSV F monoclonal antibody-resistant mutants and reveal flexibility for the side chain of a key antigenic residue on PreF. This work provides the basis for a comprehensive understanding of RSV F trimer specificity with implications in vaccine design and quality assessment of PreF-based immunogens.