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1.
Visacane is a sugarcane quarantine station located in the South of France, far away from sugarcane growing areas. Visacane imports up to 100 sugarcane varieties per year, using safe control and confinement measures of plants and their wastes to prevent any risk of pathogen spread outside of the facilities. Viruses hosted by the imported material are either known or unknown to cause disease in cultivated sugarcane. Poaceae viruses occurring in plants surrounding the quarantine glasshouse are currently unknown. These viruses could be considered as a source of new sugarcane infections and potentially cause new sugarcane diseases in cases of confinement barrier failure. The aim of this study was to compare the plant virome inside and outside of the quarantine station to identify potential confinement failures and risks of cross infections. Leaves from quarantined sugarcane varieties and from wild Poaceae growing near the quarantine were collected and processed by a metagenomics approach based on virion-associated nucleic acids extraction and library preparation for Illumina sequencing. While viruses belonging to the same virus genus or family were identified in the sugarcane quarantine and its surroundings, no virus species was detected in both environments. Based on the data obtained in this study, no virus movement between quarantined sugarcane and nearby grassland has occurred so far, and the confinement procedures of Visacane appear to be properly implemented.  相似文献   

2.
Due to high mutation rates, populations of RNA viruses exist as a collection of closely related mutants known as a quasispecies. A consequence of error-prone replication is the potential for rapid adaptation of RNA viruses when a selective pressure is applied, including host immune systems and antiviral drugs. RNA interference (RNAi) acts to inhibit protein synthesis by targeting specific mRNAs for degradation and this process has been developed to target RNA viruses, exhibiting their potential as a therapeutic against infections. However, viruses containing mutations conferring resistance to RNAi were isolated in nearly all cases, underlining the problems of rapid viral evolution. Thus, while promising, the use of RNAi in treating or preventing viral diseases remains fraught with the typical complications that result from high specificity of the target, as seen in other antiviral regimens.  相似文献   

3.
The list of recently discovered gastrointestinal viruses is expanding rapidly. Whether these agents are actually involved in a disease such as diarrhea is the essential question, yet difficult to answer. In this review a summary of all viruses found in diarrhea is presented, together with the current knowledge about their connection to disease.  相似文献   

4.
Background. Based on the evidence that vitamin D is involved in the development of immune system and vitamin D receptor gene is associated with asthma, we supposed that vitamin D is related to the development of asthma. Methods. Asthma patients were identified from the Swedish Hospital Discharge Register and the hospitalization rate was examined by different seasons and regions. Standardized incidence ratios (SIRs) for asthma were examined among patients hospitalized for osteoporosis compared with the general population. Results. A total of 172,384 patients were hospitalized for asthma in Sweden during 1965–2007. More patients were hospitalized in winter and North Sweden than in summer and South Sweden. The risk of asthma after osteoporosis was significantly increased, giving an overall SIR of 2.93. The risk was higher in male patients when compared with female subjects. Patients hospitalized for osteoporosis at age younger than 55 showed a high risk. Reversing the analyses and examining the risk of osteoporosis after hospitalization of asthma, SIR was significantly increased (3.54). Conclusion. Our study suggests that vitamin D, as indicated by the high risk of asthma after osteoporosis and the seasonal and regional variations of hospitalization, could play an important role for the development of asthma.  相似文献   

5.
Marigold plants with symptoms of mosaic, crinkle, leaf curl and necrosis were observed and small RNA and ribo-depleted total RNA deep sequencing were conducted to identify the associated viruses. Broad bean wilt virus 2, cucumber mosaic virus, turnip mosaic virus, a new potyvirus tentatively named marigold mosaic virus (MMV) and a new partitivirus named as marigold cryptic virus (MCV) were finally identified. Complete genome sequence analysis showed MMV was 9811 nt in length, encoding a large polyprotein with highest aa sequence identity (57%) with the putative potyvirus polygonatumkingianum virus 1. Phylogenetic analysis with the definite potyviruses based on the polyprotein sequence showed MMV clustered closest to plum pox virus. The complete genome of MCV comprised of dsRNA1 (1583 bp) and dsRNA2 (1459 bp), encoding the RNA-dependent RNA polymerase (RdRp), and coat protein (CP), respectively. MCV RdRp shared the highest (75.7%) aa sequence identity with the unclassified partitivirus ambrosia cryptic virus 2, and 59.0%, 57.1%, 56.1%, 54.5% and 33.7% with the corresponding region of the definite delta-partitiviruses, pepper cryptic virus 2, beet cryptic virus 3, beet cryptic virus 2, pepper cryptic virus 1 and fig cryptic virus, respectively. Phylogenetic analysis based on the RdRp aa sequence showed MCV clustered into the delta-partitivirus group. These findings enriched our knowledge of viruses infecting marigold, but the association of the observed symptom and the identified viruses and the biological characterization of the new viruses should be further investigated.  相似文献   

6.
Abstract: Antidiuretic hormone (ADH) and melatonin in plasma were measured every 4 hr during a 24-hr period in 69 elderly volunteers (42 males and 27 females) aged 75.6 ± 8.8 years (± SD) and 73.5 ± 9.5 years, respectively. The population was divided into three groups, which were examined February 27–28, April 25–26, and November 14–15. For the males, the mean ADH level during 24 hr was lowest in April and highest in November with a level five times higher than in April. The ADH level in February was about three times higher that in April. Females did not show any seasonal variation in the ADH system. The melatonin levels were lowest in November, higher in February, and even higher in April in both male and female volunteers. The ADH increased with age in males (R2= 0.13; P < 0.05) but not in females (R2= 0.07; NS). The melatonin concentration decreased with age for the whole group, aged 60–98 years.  相似文献   

7.
Vaccines and therapeutics targeting viral surface glycoproteins are a major component of disease prevention for respiratory viral diseases. Over the years, vaccines have proven to be the most successful intervention for preventing disease. Technological advances in vaccine platforms that focus on viral surface glycoproteins have provided solutions for current and emerging pathogens like SARS-CoV-2, and our understanding of the structural basis for antibody neutralization is guiding the selection of other vaccine targets for respiratory viruses like RSV. This review discusses the role of viral surface glycoproteins in disease intervention approaches.  相似文献   

8.
A high prevalence and diversity of avian influenza (AI) viruses were detected in a population of wild mallards sampled during summer 2011 in California, providing an opportunity to compare results obtained before and after virus culture. We tested cloacal swab samples prior to culture by matrix real-time PCR, and by amplifying and sequencing a 640bp portion of the hemagglutinin (HA) gene. Each sample was also inoculated into embryonated chicken eggs, and full genome sequences were determined for cultured viruses. While low matrix Ct values were a good predictor of virus isolation from eggs, samples with high or undetectable Ct values also yielded isolates. Furthermore, a single passage in eggs altered the occurrence and detection of viral strains, and mixed infections (different HA subtypes) were detected less frequently after culture. There is no gold standard or perfect reference comparison for surveillance of unknown viruses, and true negatives are difficult to distinguish from false negatives. This study showed that sequencing samples prior to culture increases the detection of mixed infections and enhances the identification of viral strains and sequences that may have changed or even disappeared during culture.  相似文献   

9.
Objective The aim of this study was to clarify the circadian and seasonal variations in addition to identify sex-based differences in Japanese patients with Takotsubo syndrome (TTS). Methods The authors conducted a retrospective observational study to analyse the differences between the groups based on sex. Patients The patients were registered out of each institute registry of the acute coronary syndrome (ACS) which contains a total of 10,622 cases in eight academic hospitals in east Japan. Results Data for 344 consecutive TTS (73 male and 271 female) were extracted from each hospital registry. In-hospital mortality was higher in the male group than in the female group (18% vs. 7%; p=0.005). With regard to the circadian variations in all study patients, TTS events occurred most often in the afternoon and least often during the night. Moreover, the patterns of circadian variations in the female and male groups were the same as that of all study patients. TTS events occurred most frequently in the autumn and least often in the spring in the whole study cohort. Moreover, the seasonal variation in the female group showed the same pattern as that of the whole cohort. However, there were no significant seasonal differences in the incidence of TTS in the male group. Conclusion In a multicenter study in Japan, seasonal variation was observed in the female group but not in the male group. Circadian variation was observed in both groups. These results suggested that the pathogenesis and clinical features of TTS might therefore differ according to sex.  相似文献   

10.
The clinical presentation of tick-borne encephalitis virus (TBEV) infection varies from asymptomatic to severe meningoencephalitis or meningoencephalomyelitis. The TBEV subtype has been suggested as one of the most important risk factors for disease severity, but TBEV genetic characterization is difficult. Infection is usually diagnosed in the post-viremic phase, and so relevant clinical samples of TBEV are extremely rare and, when present, are associated with low viral loads. To date, only two complete TBEV genomes sequenced directly from patient clinical samples are publicly available. The aim of this study was to develop novel protocols for the direct sequencing of the TBEV genome, enabling studies of viral genetic determinants that influence disease severity. We developed a novel oligonucleotide primer scheme for amplification of the complete TBEV genome. The primer set was tested on 21 clinical samples with various viral loads and collected over a 15-year period using the two most common sequencing platforms. The amplicon-based strategy was compared to direct shotgun sequencing. Using the novel primer set, we successfully obtained nearly complete TBEV genomes (>90% of genome) from all clinical samples, including those with extremely low viral loads. Comparison of consensus sequences of the TBEV genome generated using the novel amplicon-based strategy and shotgun sequencing showed no difference. We conclude that the novel primer set is a powerful tool for future studies on genetic determinants of TBEV that influence disease severity and will lead to a better understanding of TBE pathogenesis.  相似文献   

11.
Development of High-Throughput Sequencing (HTS), also known as next generation sequencing, revolutionized diagnostic research of plant viruses. HTS outperforms bioassays and molecular diagnostic assays that are used to screen domestic and quarantine grapevine materials in data throughput, cost, scalability, and detection of novel and highly variant virus species. However, before HTS-based assays can be routinely used for plant virus diagnostics, performance specifications need to be developed and assessed. In this study, we selected 18 virus-infected grapevines as a test panel for measuring performance characteristics of an HTS-based diagnostic assay. Total nucleic acid (TNA) was extracted from petioles and dormant canes of individual samples and constructed libraries were run on Illumina NextSeq 500 instrument using a 75-bp single-end read platform. Sensitivity was 98% measured over 264 distinct virus and viroid infections with a false discovery rate (FDR) of approximately 1 in 5 positives. The results also showed that combining a spring petiole test with a fall cane test increased sensitivity to 100% for this TNA HTS assay. To evaluate extraction methodology, these results were compared to parallel dsRNA extractions. In addition, in a more detailed dilution study, the TNA HTS assay described here consistently performed well down to a dilution of 5%. In that range, sensitivity was 98% with a corresponding FDR of approximately 1 in 5. Repeatability and reproducibility were assessed at 99% and 93%, respectively. The protocol, criteria, and performance levels described here may help to standardize HTS for quality assurance and accreditation purposes in plant quarantine or certification programs.  相似文献   

12.
The aim of the work was an experimental evaluation of the characteristics of the kit for the rapid immunochemical detection of orthopoxviruses (OPV). The kit is based on the method of one-stage dot-immunoassay on flat protein arrays using gold conjugates and a silver developer. Rabbit polyclonal antibodies against the vaccinia virus were used as capture and detection reagents. The sensitivity of detection of OPV and the specificity of the analysis were assessed using culture crude preparations (monkeypox virus, vaccinia virus, rabbitpox virus, cowpox virus, and ectromelia virus), a suspension from a crust from a human vaccination site as well as blood and tissue suspensions of infected rabbits. It has been shown that the assay using the kit makes it possible to detect OPV within 36 min at a temperature of 18–40 °C in unpurified culture samples of the virus and clinical samples in the range of 103–104 PFU/mL. Tests of the kit did not reveal cross-reactivity with uninfected cell cultures and viral pathogens of exanthematous infections (measles, rubella and chicken pox). The kit can be used to detect or exclude the presence of a virus threat in samples and can be useful in various aspects of biosecurity. The simplicity of analysis, the possibility of visual accounting the and interpretation of the results make it possible to use the test in laboratories with a high level of biological protection and in out-of-laboratory conditions.  相似文献   

13.
选择性扩增法检测乙肝病毒前c区终止变异及其优点   总被引:3,自引:0,他引:3  
本文建立一种简单而灵敏度高的选择性聚合酶链反应检测乙型肝炎病毒前C区终止变异,在47例慢性乙型肝炎中检出前C区终止变异41例,在慢性肝炎,肝硬化和重症肝炎中的检出率分别为82%,100%和100%,在e抗原阳性和e抗体阳性中的检出率分别为78%和90%,结果提示,我国慢性乙型肝炎存在很高的前C区终止变异株感染度,即使是e抗原阳性的慢性乙型肝炎。  相似文献   

14.
Viruses cause important yield losses in kiwifruit. Here, we studied the occurrence and population structure of the major kiwifruit viruses in the Sichuan province of China. RT-PCR results showed the presence of Actinidia virus A (AcVA), Actinidia virus B (AcVB), Actinidia chlorotic ringspot-associated virus (AcCRaV), and the cucumber mosaic virus (CMV). AcCRaV was widely distributed, followed by CMV. These two viruses were often detected in co-infection with AcVA and AcVB. The virus detection rate was positively correlated with vine age. Four phylogenetic groups of AcVA and AcVB were identified, with AcVA isolates clustering mainly in subgroup I, and AcVB isolates clustering mainly in subgroups II, III, and IV. All CMV isolates clustered in subgroup II, and AcCRaV isolates clustered in subgroup IA. The genome of AcVA and AcCRaV was under negative selection pressure, while the genome of AcVB and CMV was under positive selection pressure. All the viruses, except AcVB, were in a state of expansion. The full-length genome of the most widely distributed AcCRaV isolate in kiwifruits in the Sichuan province was characterized by sequencing. Unique eight-nucleotide (TTTTTGAT) repeats were found in the 5′-terminal non-coding region of the AcCRaV RNA3 in a possible association with reduced disease symptoms. This is the first study of kiwifruit viruses in Sichuan.  相似文献   

15.
High-throughput sequencing (HTS) of host plant small RNA (sRNA) is a popular approach for plant virus and viroid detection. The major bottlenecks for implementing this approach in routine virus screening of plants in quarantine include lack of computational resources and/or expertise in command-line environments and limited availability of curated plant virus and viroid databases. We developed: (1) virus and viroid report web-based bioinformatics workflows on Galaxy Australia called GA-VirReport and GA-VirReport-Stats for detecting viruses and viroids from host plant sRNA extracts and (2) a curated higher plant virus and viroid database (PVirDB). We implemented sRNA sequencing with unique dual indexing on a set of plants with known viruses. Sequencing data were analyzed using GA-VirReport and PVirDB to validate these resources. We detected all known viruses in this pilot study with no cross-sample contamination. We then conducted a large-scale diagnosis of 105 imported plants processed at the post-entry quarantine facility (PEQ), Australia. We detected various pathogens in 14 imported plants and discovered that de novo assembly using 21–22 nt sRNA fraction and the megablast algorithm yielded better sensitivity and specificity. This study reports the successful, large-scale implementation of HTS and a user-friendly bioinformatics workflow for virus and viroid screening of imported plants at the PEQ.  相似文献   

16.
We previously developed a rapid and simple gold nanoparticle(NP)-based genomic microarray assay for identification of the avian H5N1 virus and its discrimination from other influenza A virus strains (H1N1, H3N2). In this study, we expanded the platform to detect the 2009 swine-origin influenza A virus (H1N1/2009). Multiple specific capture and intermediate oligonucleotides were designed for the matrix (M), hemagglutinin (HA), and neuraminidase (NA) genes of the H1N1/2009 virus. The H1N1/2009 microarrays were printed in the same format as those of the seasonal influenza H1N1 and H3N2 for the HA, NA, and M genes. Viral RNA was tested using capture-target-intermediate oligonucleotide hybridization and gold NP-mediated silver staining. The signal from the 4 capture-target-intermediates of the HA and NA genes was specific for H1N1/2009 virus and showed no cross hybridization with viral RNA from other influenza strains H1N1, H3N2, and H5N1. All of the 3 M gene captures showed strong affinity with H1N1/2009 viral RNA, with 2 out of the 3 M gene captures showing cross hybridization with the H1N1, H3N2, and H5N1 samples tested. The current assay was able to detect H1N1/2009 and distinguish it from other influenza A viruses. This new method may be useful for simultaneous detection and subtyping of influenza A viruses and can be rapidly modified to detect other emerging influenza strains in public health settings.  相似文献   

17.
The COVID-19 outbreak has reminded us of the importance of viral evolutionary studies as regards comprehending complex viral evolution and preventing future pandemics. A unique approach to understanding viral evolution is the use of ancient viral genomes. Ancient viruses are detectable in various archaeological remains, including ancient people’s skeletons and mummified tissues. Those specimens have preserved ancient viral DNA and RNA, which have been vigorously analyzed in the last few decades thanks to the development of sequencing technologies. Reconstructed ancient pathogenic viral genomes have been utilized to estimate the past pandemics of pathogenic viruses within the ancient human population and long-term evolutionary events. Recent studies revealed the existence of non-pathogenic viral genomes in ancient people’s bodies. These ancient non-pathogenic viruses might be informative for inferring their relationships with ancient people’s diets and lifestyles. Here, we reviewed the past and ongoing studies on ancient pathogenic and non-pathogenic viruses and the usage of ancient viral genomes to understand their long-term viral evolution.  相似文献   

18.
The field of biosecurity has greatly benefited from the widespread adoption of high-throughput sequencing technologies, for its ability to deeply query plant and animal samples for pathogens for which no tests exist. However, the bioinformatics analysis tools designed for rapid analysis of these sequencing datasets are not developed with this application in mind, limiting the ability of diagnosticians to standardise their workflows using published tool kits. We sought to assess previously published bioinformatic tools for their ability to identify plant- and animal-infecting viruses while distinguishing from the host genetic material. We discovered that many of the current generation of virus-detection pipelines are not adequate for this task, being outperformed by more generic classification tools. We created synthetic MinION and HiSeq libraries simulating plant and animal infections of economically important viruses and assessed a series of tools for their suitability for rapid and accurate detection of infection, and further tested the top performing tools against the VIROMOCK Challenge dataset to ensure that our findings were reproducible when compared with international standards. Our work demonstrated that several methods provide sensitive and specific detection of agriculturally important viruses in a timely manner and provides a key piece of ground truthing for method development in this space.  相似文献   

19.
Out of hospital cardiac arrest (OHCA) remains a leading cause of mortality among adults in the United States. Environmental impact on incidence and outcomes of OHCA has not been fully investigated in recent years. Previous studies showed a possible increase in incidence and mortality in winter season and during seasons with temperature extremes. This study examines seasonal variation in incidence and outcomes of OHCA in the United States.Retrospective study of adult OHCA using the Nationwide Emergency Department Sample was carried out. Monthly incidence rate per 100,000 ED presentations was calculated. Survival rates for each month of admission were examined by hospital region. Multivariate analyses were conducted to determine the effect of the season and month of admission on survival.A total of 122,870 adult OHCA cases presented to emergency departments (EDs) in 2014 and were included. Average incidence of OHCA cases was 147 per 100,000 ED presentations. Overall survival rate in the study population was 5.6% (95% confidence intervals [CI] = 5.4%–5.9%). Patients had an average age of 65.5 (95% CI: 65.3–65.7) years and were mainly men (61.8%). Rates of OHCA presentations were highest during December and January (9.9% and 10.0%) while survival rates were lowest during December (4.6%) and highest in June (6.9%). Regional variation in OHCA outcomes was also noted with highest average survival rate in West (7.8%) and lowest in South (4.3%). After adjusting for confounders including region of hospital, Summer season (Ref: all other seasons), and more specifically month of June (Ref: all other months) were found to be positively associated with survival (OR 1.27, 95% CI [1.07–1.52], P-value = .008) and (OR 1.43, 95% CI [1.08–1.89], P-value = .012 respectively).Incidence and outcomes of out of hospital cardiac arrest presentations to the emergency departments in the United States have seasonal variation. Both incidence and mortality of OHCA increase during colder months, and survival is significantly higher in summer season or in June. Exploring how to use this variation to improve outcomes through refresher training of medical providers or through other mitigation plans is needed.  相似文献   

20.
用基孔肯雅和乙型脑炎病毒经口感染白纹伊蚊,采用免疫荧光试验对雌蚊涎腺作病毒抗原检查,结果于感染后第8 ̄14天基孔肯雅的阳性为50% ̄91.67%,乙型脑炎为70% ̄80%。试验认为,白纹伊蚊在感染后第6 ̄8天即可传播基孔肯雅和乙型脑炎病毒。  相似文献   

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