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1.
[摘要]?微小RNA (microRNA, miRNA)在宿主-病毒相互作用中起关键调节作用,参与HBV感染、复制和HBV相关疾病的调节。细胞miRNA可以通过直接结合HBV转录物或通过靶向与HBV生命周期相关的细胞因子间接调节HBV转录和复制。反过来,HBV感染也可以影响宿主细胞内的miRNA水平。HBV和miRNA之间的相互作用在HBV复制和HBV相关疾病的发病机制中发挥重要作用。本文对miRNA与HBV的相互关系进行综述,为进一步探讨HBV感染致病的分子机制和开发新的抗HBV治疗策略提供参考。  相似文献   
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《Vaccine》2022,40(19):2679-2695
Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics. Response to immunizations in this group is not well known.ObjectiveA systematic review was performed to evaluate three primary outcomes: efficacy; immunogenicity; and safety of vaccines in children with chronic conditions treated with biologics.MethodsThe protocol for our systematic review and meta-analysis was registered and published with PROSPERO. We searched electronic bibliographic databases for studies published from 2009 to 2019, focusing on vaccinations in children with chronic conditions treated with biologics.ResultsWe retrieved 532 records. Thirty-one full-text articles were selected, and 14 were included in the meta-analysis. No significant publication bias was found. Efficacy: limited data are available regarding the efficacy of vaccination, as most studies have focused on immunogenicity as surrogate outcome for efficacy. Immunogenicity: patients receiving anti-TNF-alpha therapy had a statistically significant risk of poor seroconversion (p = 0.028) and seroprotection by the serotype B influenza vaccine [inflammatory bowel disease (IBD) p = 0.013; juvenile idiopathic arthritis (JIA) p = 0.004]. We found adequate responses with H1N1 and H3N2 serotypes. Few studies existed for pneumococcal, hepatitis A virus, hepatitis B virus, varicella-zoster virus, Measles Mumps Rubella virus, and multiple vaccine administration. Safety: vaccine administration was not associated with serious side effects, but JIA patients on anti-TNF alpha therapy had a statistically significant risk of presenting with myalgia or arthralgia postinfluenza vaccine (p = 0.014).ConclusionsMore evidence concerning efficacy, immunogenicity, and safety of vaccinations is needed to guide physicians in the vaccine decision process for this pediatric population.  相似文献   
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《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases.  相似文献   
6.
《Vaccine》2022,40(23):3203-3209
Limited data are available on the responses to heterologous vaccine regimens for SARS-CoV-2, especially among countries using inactivated and adenoviral-vectored vaccines. A total of 77 participants who received heterologous inactivated COVID-19 vaccine (CoronaVac) and adenoviral-vectored vaccine (AZD1222) were enrolled in our study. There were two comparison groups vaccinated with the homologous CoronaVac (N = 79) and AZD1222 (N = 78) regimen. All sera samples were tested for anti-receptor-binding-domain IgG (anti-RBD IgG) using a chemiluminescent microparticle immunoassay (CMIA). The neutralizing activity in a subset of serum samples was tested against the original Wuhan strain and variants of concern, B.1.1.7, B.1.617.2 and B.1.351, using an enzyme-linked immunosorbent assay (ELISA)-based surrogate virus neutralization test (sVNT). The heterologous CoronaVac/AZD1222 vaccine induced higher levels of anti-RBD IgG than that of two-dose homologous CoronaVac or AZD1222 vaccines (p < 0.001). Sera samples of the CoronaVac/AZD1222 vaccine recipients elicited higher neutralizing antibody activity against the original Wuhan and all variants of concern than in the recipients of the two-dose CoronaVac. The heterologous CoronaVac followed by AZD1222 is an alternative regimen to combat with the SARS-CoV-2 variants in case of vaccine shortage with improved immunogenicity compared to the homologous CoronaVac regimen.  相似文献   
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《Vaccine》2022,40(31):4105-4115
The etiologic agents of visceral leishmaniasis are Leishmania infantum and Leishmania donovani. Despite the variety of drugs available to treat leishmaniasis, most lead to serious adverse effects, and resistance to these drugs has been reported. Currently, no leishmaniasis vaccine is available for humans. That is why the group developed transgenic L. infantum promastigote lines, which express toxic proteins after differentiation into amastigotes. That is why group developed the pFL-AMA plasmid and transfected it into L. Infantum promastigotes. This plasmid was expressed only in the amastigote form of the parasite. Sequences encoding toxic proteins (active bovine trypsin and egg avidin) were inserted in this plasmid, and the transfected parasites died after the differentiation process. In this study, two immunization protocols were performed in BALB/c mice: prime and prime-boost immunization prior to challenge with the wild-type L. infantum (WT). The parasite burdens in the spleen, liver, and bone marrow were evaluated to verify immunological protection. Histopathological analysis of the spleen and liver and the humoral immune response were also performed. The data showed that the parasite burden was reduced in prime-boosted mice in the spleen, liver, and bone marrow, indicating that mice immunized with two doses of the transfected parasites were satisfactorily protected. High levels of IgG, IgG1, and IgG2a antibodies were observed, as well as the presence of anti-inflammatory cytokine Interleukine-10 and pro-inflammatory cytokine Tumor Necrosis Factor-α (TNF-α) and Interferon-γ (IFN – γ) suggesting a Th1/Th2 mix response, in addition to the presence of multinucleated giant cells in the spleen and lymphocyte infiltration in the liver. Therefore, L. infantum transfected with a toxic plasmid is an excellent vaccine candidate against visceral leishmaniasis and the application of a boost before the challenge promotes greater protection against WT L. infantum infection.  相似文献   
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《Vaccine》2022,40(51):7500-7504
The Department of Defense has implemented a mandate that all military personnel be vaccinated against COVID-19. This article reviews the historical precedent of vaccine mandates for United States military personnel dating back to the formation of the continental army, as well as previous controversies about vaccine mandates such as the first influenza vaccine mandate and the Anthrax Vaccine Immunization Program. The historical review discusses precedent for the current COVID-19 vaccine mandate and the reception of these vaccine mandates by military personnel. The review then discusses how these historical lessons can inform the present COVID-19 vaccine mandate.  相似文献   
9.
武甜甜  张?翔 《传染病信息》2022,35(4):366-371
[摘要]?目前研究已知HBV有多种基因型,不同基因型在不同的种族、地域方面分布特点不同且HBV基因型是造成慢性感染自然史差异的原因之一,它们在感染的临床表现和抗病毒治疗的反应中起着重要作用。检测HBV基因型和了解HBV不同基因型对疾病预后的影响,对评估患者疾病结局和指导临床规划最佳治疗方案具有重要意义。   [关键词] 乙型肝炎病毒;基因型;基因突变;治疗  相似文献   
10.
《Vaccine》2022,40(12):1855-1863
Renewed COVID-19 outbreaks, stemming from the highly infectious Delta and Omicron variants, prompted rising fears of a ‘pandemic among the unvaccinated’. To address this prevalent vaccination crisis, media framing communication strategies can amplify the scientific evidence on COVID-19 vaccines to reach diverse geographic and socio-economic communities. The critical role of media framing strategies to engage and encourage large populations regarding vaccine acceptance has been rarely studied, despite growing evidence on vaccine hesitancy. The present study used a multi-method approach (i.e., content analysis and quasi-experiments) that unpacked the framing practices employed by the mainstream media in Pakistan. The findings of the content analysis revealed that the media extensively used uncertainty, conflict, consequences, and action rather than new evidence and reassurance frames in its COVID-19 related campaigns. In a series of quasi-experiments involving 720 participants, we manipulated these six frames of COVID-19 related news coverage (i.e., uncertainty, conflict, consequences, action, new evidence, and reassurance) to investigate the underlying mechanism that influences vaccine acceptance. The findings established that the message-consistent effects of media frames manifesting fear (e.g., consequence and uncertainty) and action cues made receivers more supportive of vaccination. The present study findings theoretically address the calls for a more inclusive “community-health reporting model”, besides offering new evidence on the media framing strategies to deliver more targeted, meaningful, and effective campaigns to raise public acceptance for COVID-19 vaccines.  相似文献   
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