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31.
The function of the Fc receptors γ chain (FcRγ) for the expression of the T cell receptor (TCR) complex and for T cell development, especially for T cells localized in epithelia, was investigated by analyzing FcRγ-deficient mice. In wildtype mice, CD8αα+β?TCRαβ+ T cells of intestinal intraepithelial lymphocytes (i-IEL) utilized CD3ζ homodimers and ζ-FcRγ heterodimers, whereas CD8α α+β?TCRγδ+ i-IEL used ζ-FcRγ and FcRγ homodimers in the TCR complex. On the other hand, these T cells in FcRγ-deficient mice contained only ζ homodimers. The surface expression of the TCR complex was reduced in CD8αα+β?i-IEL and dendritic epidermal T cells (DETC) in these mice, whereas the development of these T cells was normal. The degree of reduction appeared to depend on the expression level of FcRγ. In contrast to these populations, TCRγδ+ intraepithelial T cells in reproductive organs (r-IEL) were dramatically decreased, suggesting that the development of r-IEL is FcRγ-dependent, probably due to the predominant usage of FcRγ homodimers in the TCR complex. These results indicate that the FcRγ chain contributes differently to the TCR expression and to the development of T cells localized in epithelia.  相似文献   
32.
To determine the content of thyroglobulin in oxyphilic cells of the thyroid, which have been considered as non-thyroglobulin producing cells, the degree of stainability of the various oxyphilic cells for thyroglobulin was compared with that of non-oxyphilic follicular cells in either same or different lesion. A total of 13 oxyphilic lesions, including three follicular adenomas containing oxyphilic cell nodules, four pure oxyphilic cell adenomas, and six Hashimoto's thyroiditis were compared with 16 of non-oxyphilic lesions such as, seven follicular adenomas, four chronic lymphocytic thyroiditis, and five Graves' disease. Many oxyphilic cells stained positively for thyroglobulin regardless of their morphologic variation, but less intensely than the usual follicular cells in follicular adenomas, chronic lymphocytic thyroiditis, and Graves' disease. The stainability of oxyphilic cells for thyroglogulin did not show any significant correlation with morphologic features, whereas in follicular adenomas, the non-oxyphilic follicular cells forming microfollicles stained less strongly for thyroglobulin than the same cells lining large mature follicles in a reproducible way. With above findings, we concluded that oxyphilic cells maintain the functional activity in terms of thyroglobulin synthesis, although the content of the thyroglobulin is less than that of non-oxyphilic colloid forming follicular cells.  相似文献   
33.
Endogenous heparin-binding lectin purified from postmortem lung samples of two cystic fibrosis (CF) patients was compared to lectin derived from normal tissue with respect to structure, carbohydrate specificity, interaction with alginate derived from CF isolates of Pseudomonas aeruginosa, and secretion within the lung. Lectin was purified from extracts of lung tissue by gel filtration on Sepharose CL-2B followed by affinity chromatography on heparin-Sepharose. Lectin purified from either CF lung or control tissue ran as two peptides of approximately 16,000 and 13,000 molecular weight on electrophoresis in sodium dodecyl sulfate. The lectins displayed similar carbohydrate specificity and interacted in much the same way with bacterial alginate. An increase in lectin secretion was seen in CF lungs affecting the bronchial epithelial cells and the mucosal glands. The data suggest that the major changes seen in endogenous heparin-binding lectin in CF are related to the quantity and distribution of lectin secretion.  相似文献   
34.
Skin thickness of Korean adults   总被引:4,自引:0,他引:4  
Skin thickness varies considerably between different races and age-groups, between men and women, and between different regions of the body surface. A few authors reported the skin thickness of different regions of the body, but no detailed study have been performed on Asian. We performed 452 biopsies on 28 different regions of the normal skin of Korean men and women. The specimens were stained with hematoxylin-eosin and measured microscopically. The thickness of the skin (epidermis plus dermis) ranged from 521 to 1977 microm; the eyelid, prepuce, and inguinal skin was thinnest (521-626 microm), and the back was thickest (1977 microm). The thickness of the epidermis varied from 31 to 637 microm; skin thickness in the prepuce, eyelid, supraclavicular region, postauricular region, and axilla ranged from 31 to 71 microm; the buttock, dorsum of the hand, and dorsum of the foot were relatively thick (138-189 microm); the palm and sole were thickest (601-637 microm). The thickness dermis varied from 469 to 1942 microm; skin thickness in the eyelid, prepuce, inguinal region, and postauricular region ranged from 469 to 645 microm; the buttock, chest, and anterior neck were relatively thick (1318-1586 microm); the back was thickest (1942 microm). The epidermis accounted for 3.7-16.8% of the entire skin in most regions, except in the palm and sole (40.6-44.6%). Thickness data may be useful in harvesting full- or split-thickness skin grafts.  相似文献   
35.
Apoptosis is a programmed, physiologic mode of cell death that plays an important role in tissue homeostasis. As for the central nervous system, ischemic insults can induce pathophysiologic cascade of apoptosis in neurophils. Impairment of astrocyte functions during brain ischemia can critically influence neuron survival by neuronglia interactions. We aimed to elucidate the protective effect of ketamine on apoptosis by energy deprivation in astrocytes. Ischemic insults was induced with iodoacetate/ carbonylcyanide m-chlorophenylhydrazone (IAA/CCCP) 1.5 mM/20 microm or 150 microm/2 microm for 1 hr in the HTB-15 and CRL-1690 astrocytoma cells. Then these cells were reperfused with normal media or ketamine (0.1 mM) containing media for 1 hr or 24 hr. FITC-annexin-V staining and propidium iodide binding were determined by using flow cytometry. Cell size and granularity were measured by forward and side light scattering properties of flow cytometry system, respectively. An addition of ketamine during reperfusion increased the proportion of viable cells. Ketamine alleviated cell shrinkage and increased granularity during the early period, and ameliorated cell swelling during the late reperfusion period. Ketamine may have a valuable effect on amelioration of early and late apoptosis in the astrocytoma cells, even though the exact mechanism remains to be verified.  相似文献   
36.
To understand whether the p53-regulated mdm2 gene expression was altered by the Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC), the NPC-TW01 cell line was infected by EBV through IgA receptor-mediated endocytosis. The mdm2 gene was expressed only in a small fraction of the NPC cell population and could be enhanced in the EBV-infected (EBV+) cells. In the animals bearing EBV+ and EBV- NPC xenografts, the MDM2+ cells only appeared in clusters in both EBV+ and EBV- tumors with stronger expression in EBV+ cells. Cotransfection of pmdm2-Luc plus pSV40-p53 plus pCMV-LMP1 in the NPC-TW06 line that had p53 heterozygous point mutation showed stronger mdm2 promoter activity than cells cotransfected with pmdm2-Luc plus pSV40-p53, but no mdm2 promoter activity was seen in cells cotransfected with pmdm2-Luc plus pCMV-LMP1. Only the EBV-LMP1 but not the EBV-LMP2A gene could enhance p53 to upregulated mdm2 expression. Tumor cells in NPC biopsy specimens revealed similar mdm2 expression as in the animal model. It is concluded that although EBV can indirectly enhance mdm2 gene expression in tumor cells that express this gene, it cannot turn on or directly regulate mdm2 expression in cells that do not express this gene. In other words, EBV plays a role as an enhancer in NPC tumorigenesis.  相似文献   
37.
BACKGROUND: Genetic factors are likely to be involved in the pathogenesis of intracranial, ascending thoracic aorta, and infrarenal aortic abdominal aneurysms. Common genetic risk factors for these three types of aneurysms have been suggested. This review describes the results of whole-genome linkage studies on intracranial, thoracic aorta, and aortic abdominal aneurysms, and compares the genomic loci identified in these studies in search of possible common genetic risk factors for the three aneurysmal types. METHODS: A literature search of all whole-genome linkage studies performed on intracranial, thoracic aorta, and aortic abdominal aneurysms was performed. The genomic loci identified in these studies were described and compared in search of similarities between them. RESULTS: Five chromosomal regions on 3p24-25, 4q32-34, 5q, 11q24, and 19q that may play a role in the pathogenesis of two or more aneurysmal types were identified: 3p24-25 for thoracic aorta and intracranial aneurysms; 4q32-34 for aortic abdominal and intracranial aneurysms; 5q for thoracic aorta and intracranial aneurysms; 11q24 for thoracic aorta, aortic abdominal, and intracranial aneurysms; and 19q for aortic abdominal and intracranial aneurysms. CONCLUSIONS: Five chromosomal regions that may include common genetic factors for intracranial, thoracic aorta, and aortic abdominal aneurysms were identified. Further studies are needed to explore these chromosomal regions in different aneurysm patient groups and may further help to unravel the disease pathogenesis of aneurysms in general.  相似文献   
38.
Chen YH  Lee MF  Lan JL  Chen CS  Wang HL  Hwang GY  Wu CH 《Allergy》2005,60(12):1518-1523
BACKGROUND: Forcipomyia taiwana is a tiny, blood-sucking midge that cause intense pruritis and swelling in sensitive individuals. It is distributed island-wide in rural Taiwan and Southern China. Objective: This study aimed to study the allergic immune responses and identify F. taiwana allergens. METHODS: Crude whole body F. taiwana extracts were prepared with phosphate-buffered saline. The specific IgE antibody was determined by enzyme-linked immunoassay and immunoblotting. Protein was analyzed by electrospray ionization tandem mass spectrometry. RESULTS: Among the 372 subjects that were exposed to F. taiwana bites, 179 (48%) reported an immediate skin reaction with/without delay reaction and 41(11.1%) reported a solely delay reaction. The skin of 21 subjects was tested with F. taiwana extract. Of these 21 subjects, 12 (57.1%) produced immediate skin reactions and contained high levels of specific IgE antibody against F. taiwana. Immunoblotting revealed that 11 allergenic components are able to bind specific IgE. Allergens of 22, 24, 35, 36, and 64 kDa bound 50, 50, 75, 66.7, and 75% of IgE-containing sera tested, respectively. Tryptic fragments of the 24, 35, 36, and 64 kDa allergens were analyzed by ESI-MS/MS. Selected tryptic peptides of 24, 35, and 36, and 64 kDa allergens exhibited significant sequence identity with triosephosphate isomerase of Anopheles merus,Tenebrio molitor,Ochlerotatus togoi, and Chrysops vittatus, fructose 1,6-bisphosphate aldolase of Antheraea yamamai and Homalodisca coagulata, and a slow muscle myosin S1 heavy chain of Homarusamericanus and a protein with unknown function from A. gambiae, respectively. The 35 and 36 kDa proteins may represent different isoforms of the fructose 1,6-bisphosphate aldolase. CONCLUSION: We conclude that immediate reaction to F. taiwana bites is IgE mediated and the 24 (For t 1), 35 (For t 2), and 64 kDa (For t 3) proteins are candidates for major F. taiwana allergens. Further studies are needed to confirm these allergens.  相似文献   
39.
Nonvascular intervention of the urinary tract is a well-established uroradiologic subspecialty, which is more important for avoiding invasive open surgery in the age of rising demand about the value of less invasive treatment. Various kinds of nonvascular intervention are recently performed under image-guidance and are as follows: percutaneous nephrostomy, percutaneous nephrostolithotomy, percutaneous dilatation of the urinary tract, sclerotherapy for renal cysts, percutaneous catheter drainage, percutaneous foreign body retrieval and biopsy. Percutaneous nephrostomy is a basic technique to provide a direct access to urinary tract, which makes it possible to perform other interventional procedures. Although nonvascular intervention may produce some complications, it is generally considered to be less invasive than open surgery and has advantages such as short hospital stay, early return to normal life and therefore economic savings. This review is described to help clinicians easily understand the procedures, indications, techniques, and complications with figures of cases the authors experienced.  相似文献   
40.
We report a case of papillary carcinoma arising in a thyroglossal duct cyst, presenting with an anterior neck mass of a 31-year-old woman. The tumor was judged to be a primary lesion on the basis of intraoperative examination of the thyroid and pathologic findings of the mass. One year later, a small nodular mass in the left thyroid gland and lymph node enlargement of the right cervical lymph node were noted by follow-up imaging studies. Total thyroidectomy, right modified radical neck dissection and central neck dissection were performed. The thyroid gland revealed nodular hyperplasia without evidence of malignancy. On the other hand, the dissected neck lymph nodes revealed metastatic papillary carcinoma. Taken together, these findings suggested the tumor was a primary papillary carcinoma arising in the thyroglossal duct cyst.  相似文献   
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