肺纤维化鼠Ⅰ型前胶原和Ⅲ型前胶原mRNA表达及芪丹颗粒剂的干预效应

目的:观察芪丹颗粒对博莱霉素致肺纤维化鼠的Ⅰ型前胶原和Ⅲ型前胶原mRNA表达的影响,探讨其作用机制。方法:实验于2004-10/2006-10在山东省医学科学院基础所病理实验室完成。实验材料:清洁级雄性SD大鼠160只,体质量180～210g。氢化可的松琥珀酸钠50mg/支;芪丹(颗粒剂)是由黄芪、丹参、川芎等中草药加工提纯后的粗提取物制成的颗粒剂,10g/包(1g干粉相当于原生药8g)。实验分组:160只SD大鼠按随机区组设计分为正常组20只、模型组40只、芪丹颗粒剂50只、氢化可的松50只。实验干预:正常组20只气管内灌注和灌胃均用生理盐水。其余大鼠经气管内一次性灌注博莱霉素A5按0.25mL左右(5mg/kg体质量)诱导大鼠肺间质纤维化。随机取40只为模型组。取芪丹颗粒剂组和氢化可地松组大鼠各30只,分别从造模后第2天灌注芪丹颗粒剂(3125mg/kg)和腹腔注射氢化可的松(25mg/kg),药物干预后第7,14,28天麻醉下处死动物。两组各余20只分别从造模14d后灌注芪丹颗粒剂和腹腔注射氢化可的松(用量同前),于第28、42天分别处死动物。实验评估:用苏木精-伊红评价肺组织病理学变化和原位杂交方法检测各组大鼠肺Ⅰ型和Ⅲ型前胶原mRNA表达。结果:160只大鼠全部进入结果分析。①大鼠肺脏大体标本观察:对照组肺组织各观察时间点无明显改变,模型组肺组织表面凸凹不平,部分肺叶体积缩小,表面见灰白色结节。氢化可的松组与模型组相似。芪丹颗粒剂组见部分肺叶表面不光滑及大小不等结节。②肺组织病理学观察:模型组7d肺泡腔内大量巨噬细胞淋巴细胞中性粒细胞浸润,肺间质成纤维细胞增殖,28d肺泡结构破坏肺泡内见大量胶原纤维和成纤维细胞。芪丹颗粒剂组肺泡炎及肺纤维化程度均明显轻于模型组和氢化可的松组(P<0.05)。③肺间质纤维化形成中Ⅰ型、Ⅲ型前胶原mRNA表达:原位杂交显示两种前胶原mRNA表达呈动态变化,早期肺泡炎以Ⅲ型前胶原mRNA大量增生为主,晚期纤维化期以Ⅰ型前胶原mRNA增生为主。芪丹颗粒剂组Ⅲ型前胶原mRNA的表达在第14天处于最高,至28d仍维持较高的水平,芪丹颗粒剂组Ⅲ型前胶原mRNA的表达高于模型组和氢化可的松组(P<0.05)。28d,Ⅰ型前胶原mRNA的表达在第二天给药芪丹颗粒剂组和氢化可地松组及第14天给药芪丹颗粒剂组和氢化可的松组组间差异均有显著性(P<0.05)。结论:大鼠肺纤维化的早期以Ⅲ型前胶原mRNA的表达为主,晚期纤维化期以Ⅰ型前胶原mRNA的大量表达为主。芪丹颗粒可减轻博莱霉素诱导的大鼠肺泡炎及肺纤维化的程度,其机制可能通过影响了Ⅰ型和Ⅲ型前胶原mRNA的代谢和表达,从而减慢肺间质纤维化的进程。芪丹颗粒对肺间质纤维化有治疗作用,且优于氢化可的松。     

Recombinant immunoblot assay reaction patterns and hepatitis C virus RNA in blood donors and non-A, non-B hepatitis patients

To establish the value of the second-generation recombinant immunoblot assay (RIBA-2) and cDNA polymerase chain reaction (cDNA PCR) for confirmation of hepatitis C virus (HCV) infection, anti-HCV reaction patterns and the presence of HCV RNA were examined in 610 blood donors and 255 non-A, non-B hepatitis patients who were positive or indeterminate in RIBA-2. Of RIBA-2-positive donors (n = 191) and patients (n = 224), 75.4 and 89.7 percent, respectively, were HCV RNA positive. The most frequently observed anti-HCV recognition patterns in HCV RNA-positive donors and patients were c22, c33c, and c100 and/or 5- 1-1 (67.3%, 57.7%) and c22, c33c (24.8%, 29.3%). Among subjects with a RIBA-2-indeterminate result, HCV RNA was detected more often in patients (n = 31) than in donors (n = 419): 67.7 and 2.1 percent, respectively. In viremic persons with single-band reactivity in RIBA-2, this reactivity was always directed against either c22 or c33c. HCV RNA was detected by cDNA PCR in none of 162 persons with only anti-c100 and/or anti-5-1-1 reactivity. Therefore, RIBA-2 reactivity against c100 in combination with 5-1-1 should not be considered positive but indeterminate. In RIBA-2-indeterminate persons, HCV RNA detection is necessary for reliable confirmation of HCV infection.     

Reliability of the third-generation recombinant immunoblot assay for hepatitis C virus

BACKGROUND: In a confirmatory laboratory, the second-generation recombinant immunoblot assay (RIBA-2) was replaced by the third- generation RIBA (RIBA-3) in March 1993. The aim of this validation study was to compare the sensitivity and specificity of RIBA-2 and RIBA- 3 in a routine setting, by using a validated hepatitis C virus (HCV) RNA polymerase chain reaction to establish plasma viremia. STUDY DESIGN AND METHODS: RIBA-2 testing was performed (March 1991-March 1993) in 593 HCV RNA-positive and 1498 HCV RNA-negative subjects. RIBA-3 testing was performed (March 1993-May 1994) in 220 HCV RNA-positive and 530 HCV RNA-negative subjects. All samples reacted for anti-HCV in enzyme- linked immunosorbent assay. RESULTS: In HCV RNA-positive individuals, the sensitivity of RIBA-3 was significantly higher than that of RIBA-2 (99.5% vs. 93.3%, p = 0.0005). This was not caused by inclusion of the NS5 antigen, but by a higher sensitivity of the antigens c33 and c100 (RIBA-2: 94.3% and 62.6%; RIBA-3: 99.5% and 88.6%). Replacement of the c22 and c100 recombinant proteins by synthetic peptides significantly reduced nonspecific reactivity against these antigens (p < 0.0001). Unfortunately, increased nonspecific reactivity against the modified c33 antigen and the new NS5 antigen canceled out this effect. Two-band reactivity occurred more often in nonviremic persons than in viremic persons (32.7% vs. 8.2%, p < 0.0001). Risk factors for HCV infection were less frequently observed in 11 blood donors with two-band reactivity than in 6 blood donors with other positive RIBA-3 patterns (18% vs. 83%, p = 0.03). CONCLUSION: The higher sensitivity of RIBA-3 significantly reduced the number of indeterminate test results in HCV RNA-positive persons. Confirmatory laboratories must be aware of the frequent occurrence of nonspecific, isolated reactivity and even nonspecific, two-band reactivity in anti-HCV enzyme-linked immunosorbent assay-reactive blood donors.     

Impact of delayed admission to intensive care units on mortality of critically ill patients: a cohort study

Introduction  

When the number of patients who require intensive care is greater than the number of beds available, intensive care unit (ICU) entry flow is obstructed. This phenomenon has been associated with higher mortality rates in patients that are not admitted despite their need, and in patients that are admitted but are waiting for a bed. The purpose of this study is to evaluate if a delay in ICU admission affects mortality for critically ill patients.     

Spinocerebellar ataxia type-1 and spinobulbar muscular atrophy gene products interact with glyceraldehyde-3-phosphate dehydrogenase

Spinocerebellar ataxia type1 (SCA1) is one of several neurodegenerative disorders caused by expansions of translated CAG trinucleotide repeats which code for polyglutamine in the respective proteins. Most hypotheses about the molecular defect in these disorders suggest a gain of function, which may involve interactions with other proteins via the expanded polyglutamine tract. In this study we used ataxin-1, the SCA1 gene product, as a bait in the yeast two-hybrid system and identified the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase as an ataxin-1 interacting protein. In addition, the yeast two hybrid data demonstrate that wild type and mutant ataxin-1 form homo and heterodimers. Physical interaction between GAPDH and ataxin-1 was also demonstrated in vitro. To investigate if GAPDH might interact with other glutamine repeat-containing proteins involved in neurodegenerative disorders, we tested its binding to the androgen receptor which is mutated in spinobulbar muscular atrophy. The androgen receptor interacts with GAPDH both in the yeast two-hybrid system and in vitro. The binding of both ataxin-1 and the androgen receptor to GAPDH does not vary with the length of the polyglutamine tract. While provocative, these findings do not address the selective neuronal loss in each of these disorders in light of the wide expression patterns of GAPDH and the respective polyglutamine containing proteins. Nonetheless, such interactions may increase the susceptibility of specific neurons to a variety of insults and initiate degeneration.      

Phenotype, functions and fate of adoptively transferred tumor draining lymphocytes activated ex vivo in mice with an aggressive weakly immunogenic mammary carcinoma

Background

Regression of established tumors can be induced by adoptive immunotherapy with tumor draining lymph node lymphocytes activated with bryostatin and ionomycin. We hypothesized that tumor regression is mediated by a subset of the transferred T lymphocytes, which selectively infiltrate the tumor draining lymph nodes and proliferate in vivo.

Results

Adoptive transfer of B/I activated tumor draining lymphocytes induces regression of advanced 4T1 tumors, and depletion of CD8, but not CD4 T cells, abrogated tumor regression in mice. The predominant mediators of tumor regression are CD8+ and derived from CD62L^- T cells. Transferred lymphocytes reached their peak concentration (10.5%) in the spleen 3 days after adoptive transfer and then rapidly declined. Adoptively transferred cells preferentially migrated to and/or proliferated in the tumor draining lymph nodes, peaking at day 5 (10.3%) and remained up to day 28. CFSE-stained cells were seen in tumors, also peaking at day 5 (2.1%). Bryostatin and ionomycin-activated cells proliferated vigorously in vivo, with 10 generations evident in the tumor draining lymph nodes on day 3. CFSE-stained cells found in the tumor draining lymph nodes on day 3 were 30% CD8⁺, 72% CD4⁺, 95% CD44⁺, and 39% CD69⁺. Pre-treatment of recipient mice with cyclophosphamide dramatically increased the number of interferon-gamma producing cells.

Conclusions

Adoptively transferred CD8+ CD62L^low T cells are the principal mediators of tumor regression, and host T cells are not required. These cells infiltrate 4T1 tumors, track preferentially to tumor draining lymph nodes, have an activated phenotype, and proliferate in vivo. Cyclophosphamide pre-treatment augments the anti-tumor effect by increasing the proliferation of interferon-gamma producing cells in the adoptive host.