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1.
《Vaccine》2020,38(33):5337-5342
Freezing of alum-based vaccines drastically alters their colloidal composition and leads to irreversible cluster formation. The loss of stability is well described, but the impact of frost damage on the functionality of the induced and secreted antibody repertoire has not been studied in detail. We therefore applied our single-cell measurement platform to extract the frequencies of Immunoglobulin G-secreting cells in combination with individual secretion rates and affinities. We showed that, frost-damaged or not, the tested vaccine was able to generate similar frequencies of total and antigen-affine IgG-secreting cells. Additionally, the frost-damaged vaccine stimulated a similar T-cell cytokine secretion pattern when compared to the regularly stored vaccine. However, frost-damaged vaccines induced no efficient affinity maturation and a complete collapse of the affinity distribution was observed. This study unveiled the impact of frost-damage to alum-based vaccines on the induced secreted antibody repertoire, and illustrated the power of functional single-antibody analysis. 相似文献
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目的:探讨腰椎疾患对男性性功能的影响和心理干预治疗的效果.方法:157例伴有性功能障碍的男性腰椎疾患患者分为单纯腰椎疾患组(82例,A组)和继发马尾神经综合征组(75例,B组),治疗前填写国际勃起功能指数评分表(IIEF-5)、艾森克个性问卷(EPQ),同时行球海绵体肌反射(BCR)、坐骨海绵体肌反射(ICR)、阴茎背神经体感诱发电位(SSEP)潜伏期、波幅的检测.A组患者分为对照组和心理干预组;B组患者经临床分为早、中、晚期后再分为对照组和心理干预组.对照组均给予手术治疗.心理干预组除了手术治疗外,同时给予心理干预治疗.治疗后再次采用IIEF-5和BCR、ICR、SSEP检测,并与治疗前进行统计比较.结果:A组患者性功能障碍主要为轻度勃起功能障碍(ED),而B组患者主要为重度ED.A组患者BCR、ICR、SSEP检测结果同正常值相比无显著性差异(P>0.05):心理干预组IIEF-5评分较对照组显著提高(P<0.05).B组患者中,轻度ED患者潜伏期较正常值和A组延长(P<0.05),中度ED和重度ED患者潜伏期延长更加明显(P<0.05);处于临床早期的患者心理干预治疗组性功能的改善情况好于对照组(P<0.05),但是处于临床中、晚期的患者治疗组与对照组的差异不明显(P>0.05).结论:单纯腰椎疾患及临床早期马尾神经综合征患者性功能障碍的发生主要受心理因素的影响,而中晚期马尾神经综合征患者以神经功能损伤为主.心理治疗能够改善单纯腰椎疾患及临床早期马尾综合征患者的性功能,对处于临床中、晚期的马尾神经综合征患者效果不明显. 相似文献
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目的 对南阳市3年的新生儿破伤风疫情监测结果进行分析,掌握该市新生儿破伤风发病概况,有针对地制订防治对策。方法 对3年的监测资料进行分析评价。结果 1999—2001年3年的发病率分别为0.09‰、0.07‰、0.04‰,发病县3年的年发病率均小于1‰。结论 开展各种形式的宣传活动,提倡住院分娩,推广消毒接生,对育龄妇女进行破伤风类毒素接种,从而有效降低其发病率。 相似文献
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目的:利用粒细胞-巨噬细胞集落刺激因子(GM-CSF)作为基因佐剂,提高东部马脑炎病毒E2基因重组质粒的免疫效果.方法:分别扩增E2基因与GM-CSF基因,连接进入含有内部核糖体插入位点(IRES)的真核表达载体中,构建共表达质粒.Lipofectamine2000介导转染真核细胞BHK-21,反转录PCR检测E2和GM-CSF两个基因的转录,Western印迹法和间接免疫荧光法(IFA)检测细胞内E2基因表达产物的抗原性.通过肌肉注射免疫BALB/c小鼠,IFA法测定血清抗体效价,FACS测定免疫小鼠脾细胞中CD4 /CD8 淋巴细胞构成比,初步观察共表达质粒的免疫原性.结果:经酶切鉴定与序列测定证明重组共表达质粒中含有E2和GM-CSF两个基因且序列正确.转染细胞的反转录PCR可见E2和GM-CSF两个基因的转录.Western印迹结果可见转染细胞的裂解液在相对分子质量50 000位置有特异性条带.将转染细胞制成荧光抗原片,经IFA检测可见胞浆中出现特异荧光.免疫小鼠的最高血清抗体效价为1:160,但细胞免疫未观察到明显的提高.结论:构建的共表达质粒pE2-IRES-mGM-CSF具有良好的免疫原性,能有效刺激小鼠特异性体液免疫应答,提高了E2基因重组质粒诱导的血清抗体效价. 相似文献
6.
Domenico de Aloysio Paola Altieri Paola Penacchioni Matteo Salgarello Vito Ventura 《Maturitas》1998,29(3):107-264
Objectives: To evaluate and to compare the bleeding patterns obtained with two regimens of hormone replacement therapy given to early postmenopausal women with asymptomatic uterine leiomyomas. Methods: In this randomised prospective 1-year study 50 early postmenopausal women with one to four asymptomatic uterine leiomyomas were enrolled into two study-groups to take two regimens of hormone replacement therapy for 12 28-day cycles: (A) Tibolone, 2.5 mg/day; (B) conjugated equine estrogens (CEE), 0.625 mg/day plus medroxyprogesterone acetate (MPA), 5 mg/day. The bleeding patterns and the changes in uterine volume of the 47 outpatients who completed the study were evaluated and compared. Results: Amenorrhea incidence was higher in group A (75.0% of the cycles) than in group B (65.6% of the cycles), while irregular bleeding and irregular spotting incidences were higher in group B (29.7 and 4.7% of the cycles, respectively) compared to group A (22.6 and 2.4% of the cycles, respectively). The mean bleeding and spotting lengths were not statistically different between patients in group A and those in group B. Finally, at the end of the study period transvaginal ultrasonography showed no significant change in leiomyoma size. Conclusions: The results demonstrate that, in early postmenopausal patients with asymptomatic uterine leiomyomas, Tibolone treatment seems to be preferable compared to CEE–MPA continuous combined treatment in relation to the lesser occurrence of irregular bleeding. Furthermore, neither Tibolone nor CEE–MPA therapy, at the doses used here, promote fibroid growth. 相似文献
7.
The genome of equine arteritis virus (EAV) produces a 3 coterminal-nested set of six subgenomic (sg) viral RNAs during virus replication cycle, and each set possesses a common leader sequence of 206 nucleotides (nt) in length derived from the 5 end of the viral genome. Given the presence of the leader region within both genomic and sg mRNAs, it is likely to contain cis-acting signals that may interact with cellular or viral proteins for RNA synthesis. Gel mobility shift assays indicated that proteins in Vero cell cytoplasmic extracts formed complexes with the positive (+) and negative (-) strands of the EAV leader RNA. Several cell proteins with molecular masses ranging from 74 to 31 kDa and 58 to 32 kDa were detected in UV-induced cross-linking assays with the EAV leader RNA (+) and (-) strands, respectively. In both cases, intense bands were observed at the 58–52 kDa molecular weight markers. Results from competition gel mobility shift assays using overlapping cold RNA probes spanning the leader RNA (+) strand indicated that nt 140–206 are not necessary for binding to cell proteins. 相似文献
8.
Somasundaram R Satyamoorthy K Caputo L Yssel H Herlyn D 《Clinical and experimental immunology》2004,135(2):247-252
Major histocompatibility complex (MHC) class II-dependent antigens not only activate CD4+ T helper (Th) cells, but also cytolytic T lymphocytes and effector cells of the innate immune system. These antigens therefore are candidate vaccines against cancer and infectious agents. We have developed a novel approach using a model antigen, tetanus toxoid (TT), which provides the basis for the establishment of a novel strategy of cloning Th antigens. In the TT model system, a cDNA library encoding part of the TT light chain which contained a TT-associated Th epitope recognized by TT-specific Th clones was displayed on a phage vector (TT-phage) and presented to TT-specific Th cells by autologous Epstein-Barr virus-transformed B cells (APC). These TT-phages were able to specifically activate two different TT-specific CD4+ Th cell lines as demonstrated both in [3H]thymidine incorporation and cytokine release assays. Th cell stimulation by TT-phages was significant at a ratio of one TT-phage in 50 irrelevant phages. The described approach provides the basis for the development of a novel strategy of cloning MHC class II-dependent Th antigens, using available Th cells. This strategy has several potential advantages over existing antigen cloning methods or biochemical peptide isolation. 相似文献
9.
G. N. Kryzhanovskii V. I. Fedorova R. N. Glebov R. M. Kulygina O. P. Sakharova 《Bulletin of experimental biology and medicine》1975,79(4):367-370
It was shown by electrophoresis on polyacrylamide gel that the content of proteins with low electrophoretic mobility rises in a Triton extract of the fractions of synaptic structures from the spinal cord tissue of rats with local tetanus, whereas no change was found in the protein spectrum in the dodecyl sulfate extract. In experiments in vitro tetanus toxin stimulated the incorporation of lysine-H3 into total proteins of cortical synaptosomes.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 79, No. 4, pp. 19–22, April, 1975. 相似文献
10.
Analysis of the Virus Population Present in Equine Faeces Indicates the Presence of Hundreds of Uncharacterized Virus Genomes 总被引:7,自引:0,他引:7
Virus DNA was isolated from horse faeces and cloned in a sequence-independent fashion. 268 clones were sequenced and 178140 nucleotides of sequence obtained. Statistical analysis suggests the library contains 17560 distinct clones derived from up to 233 different virus genomes. TBLASTX analysis showed that 32% of the clones had significant identity to GenBank entries. Of these 63% were viral; 20% bacterial; 7% archaeal; 6% eukarya; and 5% were related to mobile genetic elements. Fifty-two percent of the virus identities were with Siphoviridae; 26% unclassified phages; 17% Myoviridae; 4% Podoviridae; and one clone (2%) was a vertebrate Orthopoxvirus. Genes coding for predicted virus structural proteins, proteases, glycosidases and nucleic acid-binding proteins were common. 相似文献