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101.
Evans DL Kaur H Leary J Praveen K Jaso-Friedmann L 《Developmental and comparative immunology》2005,29(12):1049-1064
Nonspecific cytotoxic cells (NCC) are the first identified and most extensively studied killer cell population in teleosts. NCC kill a wide variety of target cells including tumor cells, virally transformed cells and protozoan parasites. The present study identified a novel evolutionarily conserved oligodeoxynucleotide (ODN) binding membrane protein expressed by channel catfish (Ictalurus punctatus) NCC. Peptide fingerprinting analysis of the ODN binding protein (referred to as NCC cationic anti-microbial protein-1/ncamp-1) identified a peptide that was used to design degenerate primers. A catfish NCC cDNA library was used as template with these primers and the PCR-amplified product was sequenced. The translated sequence contained 203 amino acids (molecular mass of 22,064.63 Da) with characteristic lysine rich regions and a pI=pH 10.75. Sequence comparisons of this protein indicated similarity to zebrafish (51.2%) histone family member 1-X and (to a lesser extent) to trout H1. A search of EST databases confirmed that ncamp-1 is also expressed in various tissues of channel catfish as well as zebrafish. Inspection for signature repeats in ncamp-1 and comparisons with histone-like peptides from different species indicated the presence of multiple lysine based motifs composed of AKKA or PKK repeats. The novel protein was cloned, expressed in E. coli and the recombinant was used to generate rabbit anti-serum. The recombinant ncamp-1 bound GpC and CpG ODNs and was detected with homologous anti-ncamp-1 polyclonal antibodies. Western blots of NCC membranes using anti-ncamp-1 serum detected a 29 kDa protein. Binding competition experiments demonstrated that anti-ncamp-1 antibodies and GpC bound to the same protein on NCC. Two different truncated forms of ncamp-1 as well as the full-length recombinant protein exhibited anti-microbial activity. The present study demonstrated the expression by NCC of a new membrane protein that may participate in the recognition of bacterial DNA and as such participate in innate anti-microbial immune responses in teleosts. 相似文献
102.
William B. Hansen Anne E. Raynor Bonnie H. Wolkenstein 《Journal of behavioral medicine》1991,14(3):205-224
Heavy drinkers, moderate drinkers, light drinkers, and nondrinkers were asked to rate a variety of negative health and social consequences of using alcohol. Subjects made probability ratings for fictional others who were heavy, moderate, or light drinkers or nondrinkers. Subjects also made probability ratings for themselves as hypothetical heavy, moderate, or light drinkers or nondrinkers and for themselves actually. A pattern of perceived personal immunity was found across groups. Subjects rated fictional others and themselves as hypothetical drinkers to be more likely to experience negative consequences than their actual selves. All groups of subjects (heavy, moderate, and light drinkers and abstainers) rated their actual chances of experiencing negative consequences to be approximately equal. In contrast, heavy drinkers saw the effects of drinking for other heavy drinkers as less likely than did subjects who had light or abstinent drinking patterns who rated fictional heavy drinkers. These findings suggest that individuals who drink more tend to deny the potential harm that may result from alcohol consumption. Short-term social consequences were viewed as most likely to occur. Long-term consequences were perceived as least likely to occur.This research was supported in part by grant 1-R01-AA06201 from the National Institute on Alcohol Abuse and Alcoholism. 相似文献
103.
We undertook to determine whether previous exposure in the nest is necessary to establish the attractiveness of the maternal pheromone or whether that attractiveness is innately based. In Experiment 1 we showed that the pheromone is a prepotent stimulus insofar as it is approached in preference to a different but equally familiar odor. Experiment 2 demonstrated that when pups are denied previous exposure to the pheromone they nonetheless approach the pheromone preferentially in a choice test involving a pheromone-emitting and a non-pheromone-emitting female. And finally, in Experiment 3, we again used pups that had been isolated from the pheromone. Here, however, the choice was between a pheromone-emitting female and a female which, while non-pheromone-emitting, carried a thoroughly familiar nest odor. The pups decisively chose the pheromone-emitting female. We conclude that pheromonal attractiveness is innately based and suggest that the pheromone itself may have been selected as a signal during the course of evolution. 相似文献
104.
目的研究腺样体肥大患儿血清炎症介质、淋巴细胞亚群表达特征及其与患儿预后的相关性。方法选取浙江中医药大学附属第三医院收治的86例腺样体肥大患儿(观察组)和86例健康儿童(对照组)作为研究对象,采集血液标本测定血清炎症介质及淋巴细胞亚群相关指标,对比两组儿童的测定结果。分析腺样体肥大患儿的肥大程度、腺样体再增生情况,对比不同肥大程度患儿的血清指标,并分析各指标与患儿病情程度及预后(腺样体再增生)的关系。结果观察组患儿肿瘤坏死因子-α(TNF-α)、可溶性白细胞介素-2受体(sIL-2R)及白细胞介素-6(IL-6)水平分别为(492.44±50.56)mg/L、(420.48±61.79)U/ml及(33.65±4.51)pg/ml,对照组儿童分别为(301.22±41.65)mg/L、(236.55±57.90)U/ml及(16.25±3.27)pg/ml,差异均有统计学意义(t=16.004,P<0.05;t=20.311,P<0.05;t=8.995,P<0.05)。观察组CD4+、CD8+及CD4+/CD8+水平分别为(35.75±7.05)、(16.22±2.69)及(1.46±0.67),对照组分别为(34.25±4.53)、(17.62±2.35)及(1.40±0.62),差异均无统计学意义(t=1.036,P>0.05;t=0.905,P>0.05;t=0.823,P>0.05)。相比腺样体中度肥大患儿,重度肥大患儿的TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平明显更高(P<0.05)。相比未增生患儿,腺样体再增生患儿的TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平明显更高(P<0.05)。相关分析显示,患儿腺样体肥大程度与TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平均呈正相关(P<0.05)。患儿腺体再增生与TNF-α、sIL-2R、IL-6、CD4+及CD4+/CD8+水平也呈正相关(P<0.05)。结论腺样体肥大患儿的血清炎症介质及部分T淋巴细胞亚群表达显著升高,其与腺样体肥大程度、患儿预后密切相关。 相似文献
105.
Marcello Dallio Mario Romeo Antonietta Gerarda Gravina Mario Masarone Tiziana Larussa Ludovico Abenavoli Marcello Persico Carmelina Loguercio Alessandro Federico 《Nutrients》2021,13(5)
Metabolic- (dysfunction) associated fatty liver disease (MAFLD) represents the predominant hepatopathy and one of the most important systemic, metabolic-related disorders all over the world associated with severe medical and socio-economic repercussions due to its growing prevalence, clinical course (steatohepatitis and/or hepatocellular-carcinoma), and related extra-hepatic comorbidities. To date, no specific medications for the treatment of this condition exist, and the most valid recommendation for patients remains lifestyle change. MAFLD has been associated with metabolic syndrome; its development and progression are widely influenced by the interplay between genetic, environmental, and nutritional factors. Nutrigenetics and nutrigenomics findings suggest nutrition’s capability, by acting on the individual genetic background and modifying the specific epigenetic expression as well, to influence patients’ clinical outcome. Besides, immunity response is emerging as pivotal in this multifactorial scenario, suggesting the interaction between diet, genetics, and immunity as another tangled network that needs to be explored. The present review describes the genetic background contribution to MAFLD onset and worsening, its possibility to be influenced by nutritional habits, and the interplay between nutrients and immunity as one of the most promising research fields of the future in this context. 相似文献
106.
Sina Schwarzkopf Adalbert Krawczyk Dietmar Knop Hannes Klump Andreas Heinold Falko M. Heinemann Laura Thümmler Christian Temme Marianne Breyer Oliver Witzke Ulf Dittmer Veronika Lenz Peter A. Horn Monika Lindemann 《Emerging infectious diseases》2021,27(1):122
We investigated immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among a group of convalescent, potential blood donors in Germany who had PCR-confirmed SARS-CoV-2 infection. Sixty days after onset of symptoms, 13/78 (17%) study participants had borderline or negative results to an ELISA detecting IgG against the S1 protein of SARS-CoV-2. We analyzed participants with PCR-confirmed infection who had strong antibody responses (ratio >3) as positive controls and participants without symptoms of SARS-CoV-2 infection and without household contact with infected patients as negative controls. Using interferon-γ ELISpot, we observed that 78% of PCR-positive volunteers with undetectable antibodies showed T cell immunity against SARS-CoV-2. We observed a similar frequency (80%) of T-cell immunity in convalescent donors with strong antibody responses but did not detect immunity in negative controls. We concluded that, in convalescent patients with undetectable SARS-CoV-2 IgG, immunity may be mediated through T cells. 相似文献
107.
Pyoeng Gyun Choe Chang Kyung Kang Hyeon Jeong Suh Jongtak Jung Kyoung-Ho Song Ji Hwan Bang Eu Suk Kim Hong Bin Kim Sang Won Park Nam Joong Kim Wan Beom Park Myoung-don Oh 《Emerging infectious diseases》2021,27(1):327
We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response. 相似文献
108.
目的:考察养正合剂的免疫调节作用,方法:对小鼠碳粒廓清速率进行测定,对三硝基氯苯(DNCB)所致迟发型超敏反应(DNCB-DTH)进行测定,对小鼠血清溶血素含量进行测定,对大鼠脾细胞产生IL-II水平进行测定.结果:养正合可使小鼠碳粒廓清速率明显升高,大剂养成合剂可显增中荷小鼠低下的DTH,显著增加接种S180株小鼠的血清溶血素含量并明显促进大鼠脾细胞的IL-II的生物活性.结论:养正合剂]可对抗环磷酰胺的免疫抑制作用,对荷瘤小鼠免疫功能有明显增强作用. 相似文献
109.
目的 研究清热消炎宁抗冠状病毒的作用,为评价其防治冠状病毒感染提供实验依据。方法 雌雄各半的96只BALB/c小鼠随机分为对照组、模型组、连花清瘟胶囊(0.546 g/kg)组和清热消炎宁片低、中、高剂量(8.72、17.44、34.89g/kg)组,每组16只。采用ip环磷酰胺联合HCoV-229E冠状病毒感染BALB/c小鼠,建立冠状病毒感染模型,通过小鼠体质量、肺指数、病毒载量、血凝滴度、肺组织病理改变来评价清热消炎宁的治疗作用;通过ELISA检测肺泡灌洗液中白细胞介素-1β(interleukin-1β,IL-1β)、IL-4、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、γ干扰素(interferon-γ,IFN-γ)和血管细胞黏附分子-1(vascular cell adhesion molecule-1,VCAM-1)水平;流式细胞术检测肺组织巨噬细胞、淋巴细胞(CD3+、CD4+)及NK细胞比例;Western blotting检测肺组织Toll样受体4(Toll-like receptor ... 相似文献
110.
胆道恶性肿瘤发病率逐年升高,其异质性高,早期诊断困难,一经确诊多为晚期。晚期胆道肿瘤病人临床治疗手段有限,预后差。以吉西他滨或氟脲类为基础的药物化疗是该类病人的基础化疗方案,国内外尚无针对胆道肿瘤标准的一、二线治疗方案的结论。近年来精准治疗和免疫治疗在多种恶性实体肿瘤中取得了很大的突破,在晚期胆道肿瘤中也显示了初步的疗效及较好的安全性,为晚期胆道肿瘤的治疗带来了新的希望。 相似文献