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991.
Respiratory syncytial virus (RSV) is a common cause of respiratory infections in infants. Effective vaccines are currently being sought, but no vaccine is thus far available. In our previous study, recombinant AIK‐C measles vaccine expressing the RSV fusion protein (MVAIK/RSV/F) was developed and protective immunity against RSV demonstrated in cotton rats. In the present study, the immunogenicity and protective effects were investigated in three cynomolgus monkeys immunized with MVAIK/RSV/F. Neutralizing test antibodies against RSV were detected and no infectious virus was recovered from the lungs of monkeys immunized with MVAIK/RSV/F after challenge. MVAIK/RSV/F has the potential to inhibit RSV infection.
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992.
Immunization using genetic expression libraries may be an improvement over conventional DNA immunization using a single gene because more epitopes are simultaneously presented to the immune system. In this study, we evaluated the effectiveness of an HIV-2 vaccine made from a genomic expression library in baboons. We found that HIV-2 expression library immunization induced HIV-2-specific memory responses but low levels of CD8+ cell anti-viral responses and neutralizing antibodies. After intravenous virus challenge using a homologous pathogenic variant, HIV-2UC2/9429, viral loads were similar in the HIV-2-immunized and control baboons. We conclude that although immunization using HIV-2 expression libraries induces immune responses, this approach does not provide protection in baboons against intravenous challenge with HIV-2.  相似文献   
993.
Aims: The main aims of this study were to clone and express a new outer membrane protein U (OmpU) from a pathogenic Vibrio harveyi SF‐1 and investigate its immune efficiency as a vaccine candidate against V. harveyi infection in turbot (Scophthalmus maximus). Methods and Results: In this study, a new gene, ompU was cloned from the genomic DNA of pathogenic V. harveyi SF‐1. The ompU gene encoded a 35 kDa protein, which was purified by Ni‐NTA His‐Bind Resin column. A DNA vaccine was constructed by inserting ompU gene into pEGFP‐N1 plasmid. Turbot were injected intramuscularly with the purified OmpU protein and the recombinant pEGFP‐N1/ompU plasmid, respectively. The fish vaccinated with the purified OmpU protein were completely protected with a relative per cent of survival (RPS) of 100% against pathogenic V. harveyi infection. Efficient protection was also found in the pEGFP‐N1/ompU vaccinated group, with a RPS of 51·4%. Significant specific antibody responses were detected in the vaccinated turbot by indirect enzyme‐linked immunosorbent assay. Conclusions: A new OmpU was cloned and expressed. Both OmpU protein vaccine and DNA vaccine showed good immune protections in turbot. Significance and Impact of the Study: The OmpU was identified to be a new effective vaccine candidate and could be used as subunit vaccine and DNA vaccine for disease control caused by pathogenic V. harveyi.  相似文献   
994.
本实验室构建的疟疾DNA疫苗经动物试验表明具有很好的免疫原性,为申请临床试验,进行了制备工艺的研究。本研究将含pcD-awte质粒的大肠杆菌DH5α在发酵罐中发酵培养,碱裂解法粗提质粒,再依次通过Sepharose 6FF分子筛层析、Plasmidselect 亲硫吸附层析和Source 30Q离子交换层析精制获得质粒纯品,并对纯品进行质量分析。结果每升培养液可获得质粒纯品43.9mg,质量符合Ferreira等推荐的药用标准。  相似文献   
995.
996.

Objectives

Limited studies have focused on how European contact and colonialism impacted Native American oral microbiomes, specifically, the diversity of commensal or opportunistically pathogenic oral microbes, which may be associated with oral diseases. Here, we studied the oral microbiomes of pre-contact Wichita Ancestors, in partnership with the Descendant community, The Wichita and Affiliated Tribes, Oklahoma, USA.

Materials and Methods

Skeletal remains of 28 Wichita Ancestors from 20 archeological sites (dating approximately to 1250–1450 CE) were paleopathologically assessed for presence of dental calculus and oral disease. DNA was extracted from calculus, and partial uracil deglycosylase-treated double-stranded DNA libraries were shotgun-sequenced using Illumina technology. DNA preservation was assessed, the microbial community was taxonomically profiled, and phylogenomic analyzes were conducted.

Results

Paleopathological analysis revealed signs of oral diseases such as caries and periodontitis. Calculus samples from 26 Ancestors yielded oral microbiomes with minimal extraneous contamination. Anaerolineaceae bacterium oral taxon 439 was found to be the most abundant bacterial species. Several Ancestors showed high abundance of bacteria typically associated with periodontitis such as Tannerella forsythia and Treponema denticola. Phylogenomic analyzes of Anaerolineaceae bacterium oral taxon 439 and T. forsythia revealed biogeographic structuring; strains present in the Wichita Ancestors clustered with strains from other pre-contact Native Americans and were distinct from European and/or post-contact American strains.

Discussion

We present the largest oral metagenome dataset from a pre-contact Native American population and demonstrate the presence of distinct lineages of oral microbes specific to the pre-contact Americas.  相似文献   
997.
Genetic analysis of adherence by oral streptococci   总被引:4,自引:0,他引:4  
Streptococci are one of the most successful bacterial colonizers of the human body and are major components of oral biofilms. The bacterial cells express multiple cell-surface adhesins that are responsible for the ability of streptococci to adhere to a wide range of substrates which include salivary and serous proteins, epithelial cells and other bacterial cells. Analysis of adherence-defective mutants has indicated the importance of high molecular mass wall-associated polypeptides and of enzymes catalyzing extracellular glucan polysaccharide synthesis to the adherence and accumulation of oral streptococci. The analysis of isogenic mutants of streptococci, generated through insertional inactivation (or allelic exchange), has confirmed the essential roles of specific surface polypeptides both to adhesive processes and to correct assembly of the cell wall layers.  相似文献   
998.
doi: 10.1111/j.1741‐2358.2010.00401.x
The clinical evaluation of the oral status in Alzheimer‐type dementia patients Background: To evaluate the oral health status in patients with Alzheimer dementia (AD), and the association of the disease severity with the oral findings. Methods: The study was conducted on the study group (31 AD patients) and the control group (47 healthy volunteers) from the Neurology Department of the Institute. Cognitive status was evaluated with the MMSE scoring system. Oral parameters, such as decaying, missing, filled teeth (DMFT) index and teeth present (PT) were evaluated in the patients. Oral hygiene status, denture status and mucosal lesions, including denture‐induced stomatitis were also investigated. Results: The study was conducted on the study group (31 AD patients) and the control group (47 healthy volunteers). Tooth brushing and denture cleaning were irregular in 22 of 31 (70%) patients with AD. The ratio of the subjects who forgot to remove their denture during the night was significantly higher in the study group than in the control group (p < 0.001). In this study, decreased cognitive functions in AD patients have been demonstrated to result in a deterioration of denture care and increased denture‐related mucosal lesions. Conclusions: These findings were considered due to decreased denture care including the non‐removal of the denture in the night in the patients with decreased cognitive functions.  相似文献   
999.
This review describes a method by which the human natural anti-Gal antibody can be exploited as an endogenous adjuvant for targeting autologous tumor vaccines to antigen-presenting cells (APCs). Tumor cells remaining in the patient after completion of surgery, radiation, and chemotherapy are the cause of tumor relapse. These residual tumor cells can not be detected by imaging, but their destruction may be feasible by active immunotherapy. Since specific tumor-associated antigens (TAAs) have not been identified for the majority of cancers, irradiated autologous tumor vaccines have been considered as an immunotherapy treatment that may elicit an immune response against the residual tumor cells expressing TAAs. However, tumor cells evolve in cancer patients in a stealthy way, i.e., they are not detected by APCs, even in the form of vaccine. Effective targeting of tumor vaccines for uptake by APCs is a prerequisite for eliciting an effective immune response which requires transport of the vaccine by APCs from the vaccination site to the draining lymph nodes. In the lymph nodes, the APCs transporting the vaccine process and present peptides, including the autologous TAA peptides for activation of the tumor-specific T cells. The required targeting of vaccines to APCs is feasible in humans by the use of anti-Gal. This antibody interacts specifically with the -gal epitope (Gal1-3Gal1-4GlcNAc-R) and is the only known natural IgG antibody to be present in large amounts in all humans who are not severely immunocompromised. The -gal epitope can be synthesized on any type of human tumor cell by the use of recombinant 1,3galactosyltransferase (1,3GT). Solid tumors obtained from surgery are homogenized and their membranes subjected to -gal epitope synthesis. Similarly, -gal epitopes can be synthesized on intact tumor cells from hematological malignancies. Administration of irradiated autologous tumor vaccines processed to express -gal epitopes results in in situ opsonization of the vaccinating cells or cell membranes due to anti-Gal binding to these epitopes. The bound antibody serves to target the autologous tumor vaccine to APCs because the Fc portion of the antibody interacts with Fc receptors on APCs. Since patients receive their own TAAs, the vaccine is customized for autologous TAAs in the individual patient. The repeated vaccination with such autologous tumor vaccines provides the immune system of each patient with an additional opportunity to be effectively activated by the autologous TAAs. In some of the immunized patients this activation may be potent enough to induce an immune-mediated eradication of the residual tumor cells expressing these TAAs.Abbreviations Ab Antibody - Ag Antigen - APC Antigen-presenting cell - DC Dendritic cell - FcR Fc receptor - -gal epitope Gal1-3Gal1-4GlcNAc-R - 1,3GT -1,3-Galactosyltransferase - KO mice Knockout mice for 1,3GT - OVA Ovalbumin - SA Sialic acid - TAA Tumor-associated antigen  相似文献   
1000.
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