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101.
102.
The effects of substance P (SP) on Salmonella minnesota R345 (Rb) binding to human peripheral blood lymphocytes (PBL) were evaluated. Two parameters of bacterial cytoadherence were considered, namely the binding lymphocytes (BL) and the number of bound-bacteria/lymphocyte (BB). The results showed that SP inhibits both BL and BB in a significant manner. Furthermore, distribution of Salmonella binding to CD4+ and CD8+ lymphocytes was studied following SP pretreatment of lymphoid cells. This neuropeptide is able to hamper the bacterial cytoadherence to both T-cell subpopulations and, in particular, the inhibitory effect on the T-suppressor/cytotoxic subset was more pronounced. These findings are discussed in terms of SP intervention in the mechanism of host protection against invading microorganisms.  相似文献   
103.
Recent immunohistochemical studies indicate the presence of a bulbospinal substance P (SP) system, as well as a bulbospinal serotonin (5-HT) system, involved in spinal pain transmission. Although electrophysiological studies indicate that SP may modulate the effects of 5-HT on post-synaptic spinal nociceptive neurons, the functional relationship between SP and 5-HT on “pain behavior” remains obscure. To bridge this gap between mechanism and behavior, the purpose of the present study was to determine specific postsynaptic behavioral effects of SP and 5-HT on local spinal nociceptive reflexes in spinally transected animals. Administration of the 5-HT agonists 5-methoxydi-methyltryptamine (5-MeODMT) (0, 0.5, 1.5, 2.0 mg/kg) and quipazine (0, 5, 10, 20 mg/kg) 2 days after transection significantly expanded the receptive field (RF) areas of three spinal reflexes, as previously reported. Intrathecal administration of SP alone (0, 0.25, 2.5, 7.5 ng) also resulted in hyperalgesia, indicated by a significant expansion of the RF areas of all three nociceptive reflexes. However, administration of SP, in animals pretreated with 5-HT agonists, decreased the 5-HT-induced expansion of RF size. Therefore, SP had opposite effects on spinal nociceptive reflexes depending on whether or not the animal was pretreated with 5-HT agonists, i.e., hyperalgesia in the absence of 5-HT agonists, and analgesia in the presence of 5-HT agonists. The two effects of SP on local spinal reflexes may be related to the anatomical organization of the two spinal SP systems: 1) SP released from primary afferents facilitates nociceptive reflexes, and 2) SP associated with the descending bulbospinal system interacts with the descending bulbospinal 5-HT system and inhibits nociceptive reflexes. The present results help explain contradictory literature regarding the effect of SP on spinal nociceptive reflexes.  相似文献   
104.
Elevated serum immunoglobulin E (IgE) and increased prevalence of atopy is reported in patients infected with human immunodeficiency virus (HIV). The elevated serum IgE may be attributed to polyclonal stimulation of B cells or IgE production against allergens, viruses, fungi and bacteria. This study investigates the prevalence of atopy in perinatally HIV-infected children, and the relationships between serum IgE (and other serum immunoglobulins) with atopy, CD4+ cell count and HIV-disease stage. Serum immunoglobulin levels, epicutaneous skin test for common aeroallergens, clinical Centers for Disease Control and Prevention (CDC) classification, CD4+ cell counts and allergy history were extracted from the charts of perinatally HIV-infected children on highly active antiretroviral therapy. The prevalence of atopy (52%) and the pattern of aeroallergen sensitivity were comparable with the US pediatric population. Serum IgE levels did not correlate with clinical disease stage. However, in non-atopic patients, serum IgE levels increased with disease progression (p = 0.02). There was an inverse relationship between the prevalence of elevated serum IgE levels and atopy with progression of disease (p = 0.019). Serum IgE did not correlate with atopy, CD4+ cell count, or duration of HIV infection or levels of serum immunoglobulins. This is the first study to show no increased prevalence of atopy in perinatally HIV-infected children compared with the general population. In advanced stages of HIV, elevated serum IgE may be specific for antigens other than those known as allergens.  相似文献   
105.
硬膜外腔阻滞对胸部手术应激反应的影响   总被引:33,自引:1,他引:32  
目的 观察硬膜外腔阻滞对胸部手术应激激素和细胞因子的影响。方法20例食管癌手术病人,随机分为两组,每组10例,即全麻复令硬膜外腔阻滞(GEA)组和全麻(GA)组,分别测定麻醉诱导前、手术2h、手术4h、术毕、术后1d及术后3d的血浆去甲肾上腺素、肾上腺素、血清促肾上腺皮质激素(ACTH)、皮质醇、C-反应蛋白、IL-6及IL-10的水平。结果 血浆去甲肾上腺素和血清皮质醇GEA组术中术后无显著改变,但GA组术毕和术后1d显著升高(P<0.05),术后3d恢复至术前水平,组间比较前者有显著差异(P<0.05)。两组血浆肾上腺素、IL-10术中术后均无显著变化。两组血清ACTH、IL-6及CRP术中术后均显著升高(P<0.05),组间比较无显著差异。结论 硬膜外腔阻滞可以减轻胸部手术的应激反应。IL-6是较CRP更灵敏的反映组织损伤的炎性指标。  相似文献   
106.
Phenotypic analysis of lymphoproliferative disorders is now considered mandatory for accurate classification which is the basis for optimum patient management. This is presently carried out in most cases using a range of antibodies recognizing B and T-cell antigens effective in paraffin sections, and an antibody to CD3 is currently a key member of such panels, indicating T-cell phenotype. Current antibodies to CD3 are polyclonal with the inherent disadvantages of this type of reagent compared to monoclonal antibodies. In this study, we have used a recombinant fusion protein representing part of the epsilon subunit of the CD3 molecule to generate a novel monoclonal antibody (NCL-CD3-PS1) effective in paraffin sections. The antibody has been characterized biochemically and by immunohistochemistry using a wide range of normal and pathological tissues. Lineage and phenotype specificity have been supported in our study and results from other laboratories are awaited with interest.  相似文献   
107.
Objective To investigate the effect of rosiglitazone on p38 mitogen-activated protein kinase (p38MAPK) pathway in polycystic kidney cyst-lining epithelial cells. Methods The cyst-lining epithelial cells (PKD cells) from human polycystic kidney were treated with rosiglitazone (10 μmol/L), peroxisome proliferator-activated receptor-γ (PPARγ) inhibitor GW9662 (10 μmol/L), rosiglitazone (10 μmol/L) +GW9662 (10 μmol/L), p38MAPK specific inhibitor SB203580 (10 μmol/L), SB203580 (10 μmol/L)+ rosiglitazone(10 μmol/L) for 2 hours followed by epidermal growth factor (EGF) stimulation. Protein expressions of p38, phuspho-p38 (p-p38) and proliferating cell nuclear antigen (PCNA) were detected by Western blot. p38 mRNA was examined by RT-PCR. Expression of c-fos and c-jun was observed by immunocytochemistry. Results (1) EGF markedly up-regulated the expressions of p38, p-p38, PCNA, c-fos anti c-jun compared with control group (P<0.01). (2) Compared with EGF treated group, rosiglitazone significantly reduced p38 activation and mRNA expression (P<0.01, respectively). Rosiglitazone, rosiglitazone+SB203580 could significantly down-regulated p-p38, PCNA, c-fos and c-jun expression (P<0.01, respectively) with no significant difference between these two groups. (3) GW9662 partially reversed the reduction effect of rosiglitazone. Conclusions Rosiglitazone can inhibit proliferation of autosomal dominant polycystic kidney disease cyst-lining epithelial cells partially through down-regulating p38 activation and reducing c-fos, c-jun and PCNA expression. The above effect of rosiglitazone is in part PPARγ-independcnt.  相似文献   
108.
ΔNp63蛋白在膀胱移行上皮癌中的表达及其临床意义   总被引:3,自引:1,他引:2  
目的 :探讨 p5 3基因家族新成员截短型p6 3(△Np6 3)在膀胱癌组织中的表达及其意义。 方法 :采用免疫组织化学SP法检测 4 0例膀胱移行上皮癌 (TCC)、6例膀胱内翻性乳头状瘤和 8例正常膀胱移行上皮中△Np6 3的表达 ,并分析△Np6 3表达与膀胱癌病理类型、临床分期的关系。 结果 :正常膀胱移行上皮、膀胱内翻性乳头状瘤、TCC中△Np6 3的阳性表达率分别为 37.5 % (3/ 8)、6 6 .7% (4/ 6 )、10 0 % (40 / 4 0 ) ,组间差异有统计学意义 (P <0 .0 1)。TCCG3 级与G2 级△Np6 3的强阳性、中度阳性表达率显著高于G1级 (P <0 .0 1)。Ta~T1期以△Np6 3弱阳性为主 (6 6 .7% ) ,随TCC浸润程度的增加 ,△Np6 3染色强度逐渐增强。T2 期△Np6 3强阳性表达率为 35 .3% ,T3 ~T4期增至 6 3.6 %。结论 :△Np6 3在TCC中高表达 ,与TCC病理分级、临床分期密切相关 ;△Np6 3可能参与TCC的发生、发展 ,是评估TCC预后的潜在因素之一。  相似文献   
109.
目的 研究Ki67、P53及微血管密度(microvessel density,MVD)在大肠肿瘤中的表达,探讨其与大肠肿瘤癌变的关系及作为早期癌变生物学标志物的可能性。方法 采用免疫组化技术分别测定正常大肠黏膜、大肠息肉及大肠癌组织标本中Ki67、P53及MVD值,共80例,分析其变化规律及相关性。结果 在正常黏膜、大肠息肉、大肠癌组中的Ki67标记指数逐渐增高(分别为11.00±10.70、39.64±17.70、52.96±26.40),组间比较差异显著(P=0.0001)。正常黏膜组P53蛋白均为阴性,大肠癌组P53蛋白表达的阳性率明显高于息肉组(P=0.0001)。Ki67、P53蛋白表达与性别、年龄、病程、病变部位、大小、大肠癌的病理类型、Dukes分期均无相关性。正常黏膜、大肠息肉、大肠癌组的MVD值(14.80±5.10、19.70±7.84、36.56±20.40)逐渐上升,3组差别显著(P=0.0001)。大肠癌中Dukes C、D期的MVD值(40.56±3.49)明显高于A、B期(29.50±2.45)(P=0.016)。Ki67与P53在各种组织中的表达呈正相关(r=0.5149,P=0.015)。联合检测Ki67及P53鉴别大肠良恶性病变的敏感度(70.37%)低于单侧Ki67(96.30%),但特异度(94.34%)明显增高。结论 Ki67标记指数可反映细胞增殖状态,指数高的大肠腺瘤易发生癌变。MVD值高的大肠癌易发生转移,MVD可作为判断大肠癌预后的参考指  相似文献   
110.
目的 观察逆转录病毒转病毒白细胞介素 10 (vIL 10 )基因在体内的表达。方法 用MSCVneo vIL 10重组体在体外转导CBA (H 2 K)小鼠的造血干细胞 (HSCs) ,给经致死照射(90 0rads)的 2 0只同基因CBA(H 2 K)小鼠注入经MSCVneo vIL 10转染的HSCs ,2× 10 6HSCs/只。酶联免疫吸附测定 (ELISA)、逆转录 聚合酶链反应 (RT PCR )、Westernblot分析vIL 10的表达。结果 移植MSCVneo vIL 10转染HSCs的 2 0只小鼠 ,移植后 8周用ELISA检测 ,其中 15只小鼠血清的vIL 10浓度为 :2 70~ 13 40ng/L ,5只小鼠血清的vIL 10为阴性。 12周后有 2只小鼠vIL 10测不出 ,13只小鼠长时间表达vIL 10达 6个月。对照组小鼠血清vIL 10均为阴性。RT PCR和Westernblot证实小鼠的器官均有vIL 10的mRNA和蛋白的表达。结论 逆转录病毒能有效地将vIL 10基因导入造血干细胞并在体内长时间表达。  相似文献   
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