Dear Editor, First discovered during 1947 in Uganda from febrile rhesus macaques, Zika virus （ZIKV） is a mosquito-borne, reemerging flavivirus historically known to be present in much of Africa and ...Asia, occasionally causing outbreaks amongst the local populace （Haddow et al., 2012）. ZIKV infections in humans are mostly asymptomatic, but a small percentage of patients may show clinical symptoms such as a fever and rash, which resolve within a week or less.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), Middle East respiratory syndrome coronavirus (MERS-CoV), and severe acute respiratory syndrome coronavirus (SARS-CoV) pose a great threat ...to humanity. Every pandemic involving these coronaviruses has seriously affected human health and economic development. Currently, there are no approved therapeutic drugs against their infections. Therefore, the development of vaccines is particularly important to combat these coronaviruses. In this review, we summarized and analyzed the progress of vaccines against SARS-CoV, MERS-CoV, and SARS-CoV-2, including inactivated vaccines, live attenuated vaccines, subunit vaccines, nucleic acid vaccines, and viral vector vaccines. In addition, we compared the levels of neutralizing antibodies in the serum of patients with these three kinds of coronaviruses at different stages, and their ability and effects against SARS-CoV-2, MERS-CoV, and SARS-CoV. This review provides useful information for vaccine evaluation and analysis.
Severe fever with thrombocytopenia syndrome virus (SFTSV) infections have recently been found in rural regions of Zhejiang. A severe fever with thrombocytopenia syndrome (SFTS) surveillance and ...sero-epidemiological investigation was conducted in the districts with outbreaks. During the study period of 2011-2014, a total of 51 SFTSV infection cases were identified and the case fatality rate was 12% (6/51). Ninety two percent of the patients (47/51) were over 50 years of age, and 63% (32/51) of laboratory confirmed cases occurred from May to July. Nine percent (11/120) of the serum samples from local healthy people without symptoms were found to be positive for antibodies to the SFTS virus. SFTSV strains were isolated by culture using Vero, and the whole genomic sequences of two SFTSV strains (01 and Zhao) were sequenced and submitted to the GenBank. Homology analysis showed that the similarity of the target nucleocapsid gene from the SFTSV strains from different geographic areas was 94.2-100%. From the constructed phylogenetic tree, it was found that all the SFTSV strains diverged into two main clusters. Only the SFTSV strains from the Zhejiang (Daishan) region of China and the Yamaguchi, Miyazakj regions of Japan, were clustered into lineage II, consistent with both of these regions being isolated areas with similar geographic features. Two out of eight predicted linear B cell epitopes from the nucleocapsid protein showed mutations between the SFTSV strains of different clusters, but did not contribute to the binding ability of the specific SFTSV antibodies. This study confirmed that SFTSV has been circulating naturally and can cause a seasonal prevalence in Daishan, China. The results also suggest that the molecular characteristics of SFTSV are associated with the geographic region and all SFTSV strains can be divided into two genotypes.
Lactobacillus plantarum strain ZJ316, a probiotic strain with several functions, was isolated from healthy newborn infant fecal samples. Here we report the finished and annotated genome sequence of ...this organism.
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•Pulsed light (PL) inhibited the growth of A. carbonarius in a dose-dependent manner.•High-energy PL decreased OTA synthetic genes expression and reduced OTA production.•PL destroyed ...cell membrane integrity, permeability, mitochondria and cell wall.•PL disturbed DNA replication, transport, energy and secondary metabolism.•A regulation model of PL on A. carbonarius by transcriptomic analysis is proposed.
Pulsed light (PL) technology has a good effect on the control of fungi in postharvest fruit. In this present work, PL inhibited the growth of Aspergillus carbonarius in a dose-dependent manner, the mycelial growth decreased by 4.83 %, 13.91 % and 30.01 % at a fluence of 4.5 J·cm−2 (PL5), 9 J·cm−2 (PL10) and 13.5 J·cm2 (PL15), respectively. When inoculated with PL15 treated A. carbonarius, the scab diameter of the pears, ergosterol and OTA content was reduced by 23.2 %, 27.9 % and 80.7 % after 7 days, respectively. The third-generation sequencing technique was applied to study the transcriptome response of A. carbonarius treated with PL. Compared with the blank control, a total number of 268 and 963 differentially expressed genes (DEGs) were discovered in the group of PL10 and PL15, respectively. To be specific, a large amount of DEGs involved in DNA metabolism were up-regulated, while most of DEGs related to cell integrity, energy and glucose metabolism, ochratoxin A (OTA) biosynthesis and transport were down-regulated. In addition, the stress response of A. carbonarius was imbalanced, including up-regulation of Catalase and PEX12 and down-regulation of taurine and subtaurine metabolism, alcohol dehydrogenase and glutathione metabolism. Meanwhile, the results of transmission electron microscopy, mycelium cellular leakage and DNA electrophoresis indicated that PL15 treatment caused mitochondrial swelling, the destroyed cell membrane permeability and imbalance of DNA metabolism. The expression of P450 and Hal involved in OTA biosynthesis pathway were down-regulated in PL treated samples detected by qRT-PCR. In conclusion, this study reveals the molecular mechanism of pulsed light on inhibiting the growth, development and toxin production of A. carbonarius.
•First EQA of SARS-CoV-2 test covered 93 laboratories of CDCs in Zhejiang Province.•Inactivated SARS-CoV-2 virus culture was used to prepare the EQA panels.•36 distinct nucleic acid extraction and ...RT-PCR methods were reported in this EQA.•Overall laboratories providing confidence in the results of new molecular tests.
The COVID-19 pandemic has necessitated the rapid expansion of laboratories that conduct SARS-CoV-2 tests. A provincial external quality assessment (EQA) scheme on SARS-CoV-2 tests was organized by Zhejiang Provincial CDC to assess the accuracy of the tests in individual CDC municipal and county laboratories in Zhejiang Province, China. Three positive samples in high, medium, and low concentrations, respectively, were prepared using the serial dilutions from the culture with the viral titer concentration of 1×106.3 TCID50/mL, and one negative sample were included. A total of 93 laboratories participated, contributing results from 36 distinct combinations of nucleic acid extraction methods and PCR reagents. There was 100% concordance among all laboratories for all EQA samples, and no false-positive or false-negative results were observed. The EQA survey provides confidence in the identification of infected individuals or asymptomatic populations and assurance for clinical and public health decision-making based on test results.
Abstract
Background
Lactobacillus plantarum
is a plant-associated bacterial species but it has also been found in human, mouse and porcine gastrointestinal tracts. It can ferment a broad spectrum of ...plant carbohydrates; it is tolerant of bile salts and low pH, and it has antagonistic potential against intestinal pathogens. However, experiments reporting the use of
L. plantarum
as a probiotic are limited. In this study, the effects of
L. plantarum
ZJ316 isolated from infant fecal samples on pig growth and pork quality were investigated.
Results
One hundred and fifty newly weaned pigs were selected randomly and divided into five groups. Group 1 was fed a diet supplemented with the antibiotic mequindox; Groups 2, 3 and 4 were fed a diet supplemented with
L. plantarum
and no antibiotic; and Group 5 was fed a mixture of mequindox and
L. plantarum.
After a 60 days initial treatment, samples were collected for evaluation. The results showed that, the
L. plantarum
ZJ316 has probiotic effects on pig growth and that these effects are dose dependent. The effects of a dose of 1 × 10
9
CFU/d were more pronounced than those of a dose of 5 × 10
9
CFU/d or 1 × 10
10
CFU/d. In Group 2 (1 × 10
9
CFU/d), the diarrhea (p = 0.000) and mortality rates (p = 0.448) were lower than in antibiotic-treated pigs (Group 1), and the daily weight gain (p = 0.001) and food conversion ratios were better (p = 0.005). Improved pork quality was associated with
Lactobacillus
treatment. pH (45 min, p = 0.020), hardness (p = 0.000), stickiness (p = 0.044), chewiness (p = 0.000), gumminess (p = 0.000) and restoring force (p = 0.004) were all significantly improved in
Lactobacillus
-treated pigs (Group 2). Although we found that
L. plantarum
exerted probiotic effects on pig growth and pork quality, the mechanisms underlying its action require further study. Polymerase chain reaction-denaturing gradient gel electrophoresis results showed that the gut bacterial communities in
Lactobacillus
- and antibiotic-treated pigs were very similar and the quantity of
L. plantarum
ZJ316 was below the detection limits of DGGE-band sequencing. The concentration of short-chain fatty acids in
Lactobacillus
- and antibiotic-treated fecal samples were not significantly different (p = 0.086). However, the villus height of ilea (p = 0.003), jejuna (p = 0.000) and duodena (p = 0.036) were found to be significantly improved by
Lactobacillus
treatment.
Conclusion
L. plantarum
ZJ316 was found to have probiotic effects, improving pig growth and pork quality. The probiotic mechanism might not involve
L. plantarum
colonization and alteration of the gut bacterial community. Rather, it might be related to the inhibition of the growth of opportunistic pathogens and promotion of increased villus height.
The chikungunya virus (CHIKV) is widespread. In Zhejiang province, China, CHIKV infection is often associated with travelers from tropical and subtropical countries. In the present study, three CHIKV ...isolates from serum samples of travelers in Zhejiang province in 2019 were sequenced, and phylogenetically analyzed to study their molecular characteristics. Sequence analysis showed that the non-structural protein and the structural protein had 37 and 28 amino acid mutations, respectively; no mutation site was found at the E1-A226 residue, which could increase the adaptability of CHIKV to
Aedes albopictus
. All three samples carried two mutations, namely, E1-K211E and E2-V264A, which were introduced to Bangladesh around late 2015 and Thailand in early 2017. Phylogenetic analysis revealed that these three CHIKVs were Indian Ocean lineage of the East Africa/Central/South Africa genotype (ECSA) and that the MF773566 strain from Bangladesh (Australia/Bangladesh 2017) had the closest evolutionary relationship. The three CHICKs imported into Zhejiang province in 2019 belonged to the ECSA genotype and had multiple amino acid variation sites. The variation in the three samples provides a certain reference for the subsequent research on CHIKV evolution.
•CA10 is one of the main agents associated with HFMD in zhejiang during 2017 to 2022.•Non EV71 associated HFMD cases, like CA10, increased after the use of EV71 vaccine.•Molecular epidemiology of ...HFMD and genetic features of CA10 were investigated.•Phylogenetic characteristics and evolutionary patterns for the CA10 were inferred.•We provided information for HFMD prevention and control.
Coxsackievirus A10 (CA10) is one of the etiological agents associated with hand, foot and mouth disease (HFMD).
We aimed to perform a retrospective analysis of the molecular epidemiological characteristics and genetic features of HFMD associated with CA10 infections in Zhejiang Province from 2017 to 2022.
Epidemiologic features were summarized. Throat swab specimens were collected and tested. The VP1 regions were sequenced for genotyping. CA10 positive samples were isolated. Whole genomes of CA10 isolations were sequenced. Nucleotide and amino acid changes were characterized. Phylogenetic trees were constructed.
The number of HFMD cases fluctuated from 2017 to 2022. Children aged below 3 years accounted for the majority (66.29%) and boys were more frequently affected than girls. Cases peaked in June. The positivity rate of HEV was 62.69%. A total of 90 strains of CA10 were isolated and 53 genomes were obtained. All CA10 in this study could be assigned to two genogroups, C (C2) and F (F1 and F3).
The clinical manifestations of HFMD associated with HEV are complex and diverse. CA10 infection may be emerging as a new and major cause of HFMD because an upward trend was observed in the proportion of CA10 cases after the use of EV71 vaccines. Different genogroups of CA10 had different geographic distribution patterns. Surveillance should be strengthened and further comprehensive studies should be continued to provide a scientific basis for HFMD prevention and control.
In China, edible shellfish are recognized as foods potentially at high risk of contamination with human Norovirus (HuNoV) and Vibrio parahaemolyticus. In this study, the antimicrobial effects of ...Chinese rice wine on HuNoV surrogates (MS2 and MNV-1) and V. parahaemolyticus in pickled mud snails immersed at different temperatures were evaluated. The optimized conditions for the wine treatment were also determined by assessing the color, odor, off-flavor, taste, and texture of the mud snails. Treatment with Chinese rice wine and immersion at 16 °C for 6 h were found to be the most effective conditions for reducing the incidence of MS2, MNV-1, and V. parahaemolyticus in the wine-treated mud snails with minimal changes to food quality. Using the nonlinear Weibull model, we show that the minimal TR values (the time required to reduce the population of pathogens by 90%) for MNV-1 (0.436 h), MS2 (0.363 h), and V. parahaemolyticus (0.202 h) were obtained for the rice-wine-containing shellfish immersed at 16 °C. Therefore, Chinese rice wine can be used as an antimicrobial agent against HuNoV and V. parahaemolyticus in wine-treated Bullacta exarata.
•Wine-treated mud snail, called Zuiniluo in China, was popular seafood in eastern China.•Chinese rice wine treatment can reduce the risk by the food-borne pathogens of zuiniluo.•Chinese rice wine treatment can improve the sensory quality of zuiniluo.•Chinese rice wine can be used as an antimicrobial ingredient against HuNoV and V. parahemolyticus in zuiniluo.
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