低剂量电离辐射对小鼠免疫器官cAMP和儿茶酚胺含量的影响

本文报道，７５ｍＧｙ／（１２．５ｍＧｙ／ｍｉｎ）单次全身Ｘ射线照射后９小时用ＳＲＢＣ免疫Ｃ５７ＢＬ／６小鼠，在免疫后４天和７天脾脏、胸腺和下丘脑ｃＡＭＰ含量均降低；而在免疫后４天脾脏去甲肾上腺素、肾上腺素和酪氨酸含量均增高，免疫后７天肾上腺素含量仍持续增高；当连接γ射线６５ｍＧｙ（０．０１５ｍＧｙ／ｍｉｎ，６ｈ／ｄ）全身照射小鼠后即刻或２９小时后免疫，脾脏和下丘脑ｃＡＭＰ含量也均降低。提示，低剂量     

低剂量辐射对TCR／CD3和CD25在小鼠胸腺细胞浆膜表达的影响

本文首次报道低剂量Ｘ射线全身照射促进胸腺细胞表面ＴＣＲ＿（α．β）、ＣＤ３和ＣＤ２５等分子的表达。已知低剂量辐射可加速胸腺细胞更新和增殖。为了探讨低剂量辐射对胸腺细胞成熟过程的影响，用免疫荧光流式细胞术检测了７５ｍＧｙＸ射线全身照射后ＴＣＲ／ＣＤ３和ＣＤ２５的表达。发现照射后４～２４ｈＴＣＲ／ＣＤ３的表达随时间推移逐步增升，表明低剂量辐射促进胸腺细胞成熟。照射后２４ｈ丝裂原激活的胸腺细胞表达ＣＤ２５显著增强，提示胸腺细胞的功能活性增高。讨论了胸腺细胞表面上述分子表达变化在促进细胞信息传递中的意义。     

下丘脑—垂体—性腺轴功能变化在低剂量辐射免疫刺激效应中的…

７５ｍＧｙＸ线全身单次照射昆明雄性小鼠。下丘脑５－ＨＴ含量增高，而血清ＬＨ、ＦＳＨ和睾丸酮水平下降，伴有脾细胞胞浆，胞核ＴＳ受体数目减少。给大鼠正丘脑注入５－ＨＴ，血清促性腺激素水平变化与７５ｍＧｙ射后小鼠血清激素变化一致。     

新疆犏牛胃肠胰系统5－羟色胺免疫活性细胞的免疫组织化学研究

用免疫组织化学ＡＢＣ法，显示新疆牛胃肠胰系统ＥＣ细胞──５ＨＴ细胞。从胃到十二指肠前段，细胞的分布密度呈上升趋势；结肠向心段分布最少；而直肠又有回升。ＥＣ细胞在胃肠中大多分布于腺中、下部，但在十二指肠多分布在绒毛底部和肠腺等处。在胰中，胰岛内ＥＣ细胞较多；胰腺腺泡细胞之间亦见有阳性细胞。消化道各段的ＥＣ细胞大多有胞突，可见２个胞突从细胞体相对两端伸出。细胞大多为梭形、蝌蚪形、锥形或卵圆形。细胞顶部胞突伸向腺腔，底部胞突伸向细胞间隙或基膜。胰腺和胰岛中ＥＣ细胞形状不规则且少见胞突。胃肠胰各处ＥＣ细胞体和胞突中５－ＨＴ免疫反应物明显。；ＤｅｐａｒｔｍｅｎｔｏｆＨｉｓｔｏｌｏｇｙａｎｄＥｍｂｒｙｏｌｏｇｙ，ＳｈｉｈｅｚｉＭｅｄｉｃａｌＣｏｌｌｅｇｅ＊，Ｓｈｉｈｅｚｉ，Ｘｉｎｊｉａｎｇ）ＢｙｕｓｉｎｇｏｆｉｍｍｕｎｏｈｉｓｔｏｃｈｅｍｉｃａｌＡＢＣｍｅｔｈｏｄ，ｔｈｅ５－ＨＴ－ｉｍｍｕｎｏｒｅａｃｔｉｖｅｃｅｌｌｓ（ＥＣｃｅｌｌｓ）ｗｅｒｅｉｄｅｎｔｉｆｉｅｄｉｎｔｈｅｇａｓｔｒｏ－ｅｎｔｅｒｏ－Ｆａｎｃｒｅａｔｉｃ（ＧＥＰ），ｓｙｓｔｅｍｏｆｔｈｅＸｉｎｊｉａｎｇｐｉｅｎｎｉｕ［ｙａｋ（）ｃａｔｔｌｅｈｙｂｒｉｄ     

亚硒酸钠对大鼠胃癌变前期胃窦粘膜G、D和EC细胞的影响

目的：探讨亚硒酸钠对大鼠胃癌变前期胃窦粘膜Ｇ细胞、Ｄ细胞和ＥＣ细胞的影响。方法：用免疫组织化学及图像分析法,观察亚硒酸钠对Ｎ－甲基－Ｎ’－硝基－Ｎ－亚硝基胍诱发的大鼠胃癌变前期胃窦粘膜Ｇ细胞、Ｄ细胞和ＥＣ细胞的变化。结果：Ｎ－甲基－Ｎ’硝基－Ｎ－亚硝基胍短期灌胃后（阳性对照组）,胃窦粘膜Ｇ、Ｄ、ＥＣ细胞的数量和平均光密度值（ＯＤ值）与正常对照组比较均显著减少（Ｐ〈０．０１）。Ｎ－甲基－Ｎ’－硝基－     

大剂量X射线头部和全身照射后神经内分泌功能的变化

本研究应用１０ＧｙＸ射线头部和全身照射动物模型，观察神经内分泌系统功能的变化。结果证实，头部照射后４８ｈ下丘脑Ｌ－ＥｎＫ和垂体Ｍ－ＥｎＫ含量降低，下丘脑ＮＥ和ＤＡ含量增高，血清ＬＨ、ＦＳＨ、ＰＲＬ、ＴＳＨ和ＧＨ水平增高；而全身照射后４８ｈ神经内分泌系统功能的变化与头部照射后变化基本相反。提示头部和全身照射后产生的神经内分泌系统功能的改变与辐射的直接作用和间接作用有关。     

下丘脑－垂体－性腺轴功能变化在低剂量辐射免疫刺激效应中的作用

７５ｍＧｙＸ线全身单次照射昆明雄性小鼠，下丘脑５－ＨＴ含量增高，而血清ＬＨ、ＦＳＨ和睾丸酮（ＴＳ）水平下降，伴有脾细胞胞浆、胞核ＴＳ受体数目减少ｑ给大鼠下丘脑注入５－ＨＴ，血清促性腺激素水平变化与７５ｍＧｙ照射后小鼠血清激素变化一致ｑ提示，低剂量辐射可激活中枢５－ＨＴ神经元，使下丘脑５－ＨＴ产生和分泌增加，性腺轴功能下调，部分解除下丘脑－垂体－性腺系统对免疫器官的张力性抑制，从而诱发免疫功能增强。     

低剂量电离辐射对免疫器官局部微环境的免疫调节作用

目的和方法：观察７５ｍＧｙＸ射线全身照射昆明系雄性小鼠后２４ｈ，其血清及胸腺和脾细胞外液对免疫功能的影响。结果：小鼠经７５ｍＧｙ照射后，其血清抑制脾细胞对ＣｏｎＡ反应性低于正常血清，其胸腺（脾）细胞外液抑制胸腺细胞３Ｈ－ＴｄＲ自发掺入能力（脾细胞对ＣｏｎＡ反应性）也明显低于正常对照组，尤以ＭＷ＜１０ｋＤ组份为著；胸腺和脾细胞外液经ＳｅｐｈａｄｅｘＧ１００层析获得的第一峰较正常对照的高，而第二峰较之为低，其中第二峰对免疫功能的抑制作用低于正常对照的第二峰更为明显。结论：低剂量辐射能够改变免疫器官局部微环境，使免疫功能增强，可能与其神经体液因子等因素的变化有关。     

人朊蛋白基因外显子Ⅰ及其上游序列具有启动子样活性

目的 鉴定朊蛋白（ＰｒＰ）基因转录启动子位置。方法 利用聚合酶链反应（ＰＣＲ）扩增人ＰｒＰ基因外显子Ⅰ及其上游序列，序列鉴定后插入ＣＡＴ报道质粒ｐＢＬ－ＣＡＴ６，分别转染ＨｅＬａ、ＣＯＳ７和Ｓｈ－ｓｙ５ｙ细胞系，检测ＣＡＴ表达值；提取三种细胞蛋白，以条带移动实验检测细胞转录激活因子ＳＰ１含量。结果 人ＰｒＰ基因外显子Ｉ及其上游序列为ＧＣ富含，带有多个ＳＰ１可能性综合位点，但无明显ＴＡＴＡ盒；瞬时转染结果显示这段序列可诱导２～３倍的ＣＡＴ表达增强；定量移动条带实验证明ＨｅＬａ细胞中含有较高浓度的ＳＰ１，而ＣＯＳ７和Ｓｈ－ｓｙ５ｙ细胞中ＳＰＩ含量极低。结论 人ＰｒＰ基因外显子Ｉ及其上游序列具有启动子样功能，为弱的非ＴＡＴＡ盒启动子；不同组织来源的细胞中ＳＰ１含量不同，在神经细胞系Ｓｈ－ｓｙ５ｙ中人ＰｒＰ基因外显子Ｉ     

胃肠细胞膜相关补体调节物CD_（46）、CD_（55）和CD_（59）的表达和调节

胃肠细胞膜相关补体调节物ＣＤ_（４６）、ＣＤ_（５５）和ＣＤ_（５９）的表达和调节［英］／ＳｃｈｍｉｔｔＣ…Ｇｙｓｔｒｏｅｎｔｅｒｏｌｏｇｙ．－１９９４；１０６（４ｐｔｚ）．－Ａ７６８胃肠上皮是人体与营养物和微生物之间的重要屏障。持久接触这些异质抗原，...     

Non-invasive method to detect and locate haemorrhagic focus of GI tract

Traditional diagnostic methods do not work well for gastrointestinal bleeding, and location of the haemorrhagic focus is even more difficult. Here a novel method with a microelectronic system is presented effectively to detect and locate the haemorrhagic focus. The outstanding advantage of this method is that it is non-invasive. The composition and working principles of the system are described in detail. Key to this system is the development of a haemoglobin (Hb) sensor. Through MEMS technology a micro haemoglobin sensor is developed and fabricated. The sensor's response performance, pH dependence and temperature dependence are tested experimentally. Initial tests suggest that the device is sufficiently sensitive to Hb concentration and insensitive to pH and temperature changes in the working range. As a result, the system has potential for development of an advanced instrument for detecting, localizing and treating gastrointestinal bleeding.     

Non-invasive method to detect and locate haemorrhagic focus of GI tract

Traditional diagnostic methods do not work well for gastrointestinal bleeding, and location of the haemorrhagic focus is even more difficult. Here a novel method with a microelectronic system is presented effectively to detect and locate the haemorrhagic focus. The outstanding advantage of this method is that it is non-invasive. The composition and working principles of the system are described in detail. Key to this system is the development of a haemoglobin (Hb) sensor. Through MEMS technology a micro haemoglobin sensor is developed and fabricated. The sensor's response performance, pH dependence and temperature dependence are tested experimentally. Initial tests suggest that the device is sufficiently sensitive to Hb concentration and insensitive to pH and temperature changes in the working range. As a result, the system has potential for development of an advanced instrument for detecting, localizing and treating gastrointestinal bleeding.     

Working out mechanisms of controlled/physiologic inflammation in the GI tract

The mucosal immune system is distinct from its systemic counterpart by virtue of its enormous antigenic exposure (commensal flora, food antigen, pathogens). Despite this, the mucosal immune system maintains a response defined as controlled or physiologic inflammation. This is regulated by many different mechanisms, among which there are physical, cellular and soluble factors. Our laboratory has focused on unique Tregs in the gut controlled by, in one instance, intestinal epithelial cells that serve as non-professional antigen-presenting cells. We believe that intestinal epithelial cells, expressing classical and non-classical MHC molecules, serve to activate Tregs and thus maintain controlled or physiologic inflammation. In this review, we describe regulatory cytokines and T cells that are one part of the emphasis of our laboratory.     

Investigation of microencapsulated BSH active lactobacillus in the simulated human GI tract

This study investigated the use of microencapsulated bile salt hydrolase (BSH) overproducing Lactobacillus plantarum 80 cells for oral delivery applications using a dynamic computer-controlled model simulating the human gastrointestinal (GI) tract. Bile salt deconjugation rates for microencapsulated BSH overproducing cells were 4.87 +/- 0.28 mumol/g microcapsule/h towards glycoconjugates and 0.79 +/- 0.15 mumol/g microcapsule/h towards tauroconjugates in the simulated intestine, a significant (P< .05) increase over microencapsulated wild-type cells. Microcapsules protected the encased cells in the simulated stomach prior to intestinal release, maintaining cell viability above 109 cfu/mL at pH 2.5 and 3.0 and above 106 cfu/mL at pH 2.0 after 2-hour residence times. In the simulated intestine, encased cell viability was maintained above 1010 cfu/mL after 3, 6, and 12-hour residence times in bile concentrations up to 1.0%. Results show that microencapsulation has potential in the oral delivery of live BSH active bacterial cells. However, in vivo testing is required.     

Detection of human JCPyV and BKPyV in diffuse large B-cell lymphoma of the GI tract

Previous studies have demonstrated that infection with human polyomavirus, such as JCPyV and BKPyV, might be associated with various human tumors. However, an association between human JCPyV and BKPyV infection and diffuse large B-cell lymphoma (DLBCL) has not been reported. The purpose of this study was to examine DLBCLs of the gastrointestinal tract for evidence of human polyomavirus infection. Nested PCR and DNA sequencing were employed for viral DNA detection and viral genotype identification. In addition, two viral proteins, the large tumor antigen (LT) and the major structural protein (VP1), were detected by immunohistochemistry (IHC). Human JCPyV and BKPyV DNA was detected in 14 out of 16 tissue samples (87.5 %), whereby nine cases were infected with JCPyV and five cases were infected with BKPyV. Both archetypal and rearranged genotypes of JCPyV and BKPyV were detected in the tissues. LT was detected in 11 tissue samples (68.75 %). However, VP1 was not detected in any of the tissue samples. The presence of human JCPyV and BKPyV DNA and protein in DLBCL tissues of gastrointestinal tract were first reported in this study. The current results provide evidence of a possible association between human JCPyV and BKPyV infection and DLBCL.     

Carcinogenesis in the GI tract: from morphology to genetics and back again.

The genetic alterations in colorectal cancer progression are determined by one of two separate and distinct underlying pathways of genomic instability. The first pathway, chromosomal instability, is characterized by allelic losses and aneuploidy. The second pathway, microsatellite instability, is characterized by an abundance of subtle DNA mutations and diploidy. Although the genes causing chromosomal instability remain unknown, microsatellite instability is caused by inactivation of a DNA mismatch repair gene (predominantly MLH1 or MSH2). Microsatellite instability is present in 15% of colorectal cancers, and is diagnosed by analysis of tumor DNA from paraffin blocks and by demonstration of loss of mismatch repair protein expression in cancers. In addition to the unique profile of genetic alterations, colorectal cancers with microsatellite instability have distinct pathologic features and improved survival. Finally, cancers from most patients with hereditary non-polyposis colorectal cancer (or Lynch syndrome) have microsatellite instability due to germline mutations in the DNA mismatch repair genes. Identification of the microsatellite instability pathway has enormous implications for the clinical investigation and management of colorectal cancer patients.     

Rabbit monoclonal anti-SATB2: identification of malignancies from lower GI tract

The differential diagnosis of metastases with no known history or a poorly differentiated subtype may present a diagnostic challenge – especially for small biopsy specimens. This study evaluated rabbit monoclonal anti-SATB2 by immunohistochemistry for neoplastic expression, sensitivity, and specificity. Ninety-five percent of primary colorectal adenocarcinoma cases displayed strong and diffuse nuclear staining with rabbit monoclonal anti-SATB2. Anti-SATB2 showed diffuse, weak, and nuclear expression in a case of medullary carcinoma of the colon, while other common colorectal markers showed no immunoreactivity. Anti-SATB2 also showed strong and diffuse nuclear staining in colorectal adenocarcinoma metastases to uterus, liver, lymph nodes, and lung (11/11, 100%). SATB2 rabbit monoclonal antibody is a sensitive and specific marker for malignancies of lower GI origin and is useful for differential diagnosis of metastatic adenocarcinomas of unknown primary.     

Peptide secretory pathways in GI tract: cytochemical contributions to regulatory physiology of the gut

Numerous biologically active peptides are produced by specialized cells of the gastrointestinal tract. Most of these peptides are also produced outside the gut, and current evidence suggests that they not only regulate digestive events per se but also participate in many other regulatory mechanisms working as hormonal, paracrine, and neuronal messengers. The physiological functions of the gastrointestinal peptides are yet very incompletely known. Immunocytochemical tracing of the destinations of neuronal and paracrine cell processes may, together with available physiological and biochemical data, provide valuable clues to the sites of actions of many of the novel regulatory peptides. Moreover, immunocytochemistry has given evidence for the occurrence of multiple secretory peptides in certain endocrine cell types and suggested that certain peptides simultaneously may be secreted by multiple endocrine, paracrine, and neural cell types. This review emphasizes the continued need for concerted cytochemical, physiological, and biochemical studies of the sites of synthesis, secretion, and action of gastrointestinal regulatory peptides.     

Transcriptional profiling suggests that secondary and primary large B-cell lymphomas of the gastrointestinal (GI) tract are blastic variants of GI marginal zone lymphoma

The pathogenetic relationship of marginal zone B-cell lymphoma (MALT lymphoma) of the gastrointestinal (GI) tract and eventually co-existing aggressive B-cell lymphoma and primary aggressive B-cell lymphoma remains to be elucidated. The RNA of laser-microdissected cells was isolated and amplified from small and/or large cell compartments of eight MALT lymphomas (small cell lymphoma, SCL), 14 GI diffuse large B-cell lymphomas (large cell lymphoma, LCL), and ten GI B-cell lymphomas with composite small and large cell compartments (ComL) and expression analyses were performed using cDNA arrays. Hierarchical cluster analysis clearly separated SCL and LCL and the small and large cell compartments of ComL. Likewise, cluster analysis with all samples of SCL, LCL, and ComL yielded two main 'small cell' and 'large cell' branches. Furthermore, 60 genes were differentially expressed between SCL and LCL, and 82 genes between the small and large cell components of ComL; 26 genes were discriminators in both settings. Use of the profiles of ComL as training sets for class prediction resulted in 95% accuracy for the classification of SCL and LCL. Collectively, the data strongly suggest that both secondary and primary aggressive B-cell lymphomas of the GI tract are blastic marginal zone lymphomas.