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31.
Nakama S Kikuchi M Yashiro T Sakamoto A Kikkawa I Ookami H Saita K Hoshino Y 《Medical molecular morphology》2005,38(3):173-180
Ossification or calcification of the ligamentum flavum (LF) is relatively common in the middle and lower cervical, thoracic, and lumbar spine but extremely rare in the upper cervical region. This clinical fact suggests that there exist local factors promoting or preventing ossification or calcification of LF. However, little is known about the differences in the ultrastructure and cellular alterations of the LF between the different spinal levels, even in the cervical spine. With electron microscopy, we examined samples of LF collected surgically from the upper and lower cervical spine regions; we then studied the apoptotic appearance of ligament cells using a preferential labeling method. We found direct evidence of apoptosis of ligament cells in the LF. Apoptosis was more apparent in the upper region samples than in the lower region samples. The spaces around the normal fibroblasts were filled with thick collagen fibrils, but the collagen fibrils disappeared around the apoptotic bodies and thin fibrils were formed. The difference of the level of apoptosis may correlate to the ultrastructual difference of LF, and our data will benefit further investigations seeking to clarify the mechanism of various pathological conditions in the human LF. 相似文献
32.
Kiyoshi Kasai Toru Kameya Takashi Okuda Paul I. Terasaki Yuichi Iwaki 《Virchows Archiv : an international journal of pathology》1987,410(3):253-261
Summary In order to explore the relationship between the expression of cancer-associated glycolipids such as sialylated Lex (SLEX) and sialylated Lea (SLEA) and the histological subtypes of lung cancers, 30 cases of small cell carcinoma (SCC) and 47 cases of non-small cell carcinoma (non-SCC) were examined immunohistochemically using monoclonal antibodies reacting with SLEX and SLEA. The forty-seven cases of non-SCC included 20 cases of adenocarcinoma, 20 of squamous cell carcinoma and 7 of large cell carcinoma. Tumour cells of most non-SCCs expressed SLEX and SLEA. In adenocarcinomas, the number of tumour cells having SLEX and SLEA was more than that of squamous cell carcinomas, large cell carcinomas and SCC. In SCC, 14 of the 30 cases were found to be positive for both antigens. Although the cancer cells of 11 cases of 17 intermediate cell type SCC had both antigens, the cells of only 3 of 13 oat cell tumours expressed SLEX and SLEA. The present study shows that SLEX and SLEA are useful markers for lung adenocarcinomas, that most cases of intermediate cell type of SCCs have characteristics similar to non-SCC but that many oat cell tumours lack them. 相似文献
33.
Yoshida C Suzukawa K Katsura Y Shimizu S Mukai HY Hasegawa Y Imagawa S Kojima H Nagasawa T 《Cancer Genetics and Cytogenetics》2004,150(1):62-65
We describe the case of a 40-year-old man whose disease was initially diagnosed as acute myelocytic leukemia. The patient achieved remission with chemotherapy, but relapsed shortly afterwards with an acute T-cell lymphoblastic leukemia. He died of intracranial bleeding. Karyotyping analysis showed a del(9p?) as a common abnormality in the leukemic cells at onset and relapse. Fluorescence in situ hybridization analysis demonstrated allelic loss of the CDKN2A gene in cells from both stages of the disease. At relapse the leukemia cells had additional abnormalities such as add(1)(p36) and del(12)(p11). We postulate that the loss of CDKN2A is involved in leukemogenesis but does not determine the lineage of the leukemic cells. Instead, abnormalities of genes at 1p36, 12p11, or both may be involved in driving a lymphoid phenotype. 相似文献
34.
Uwai Y Masuda S Goto M Motohashi H Saito H Okuda M Nakamura E Ito N Ogawa O Inui K 《Journal of human genetics》2004,49(1):40-45
35.
Wakabayashi Y Watanabe H Inoue J Takeda N Sakata J Mishima Y Hitomi J Yamamoto T Utsuyama M Niwa O Aizawa S Kominami R 《Nature immunology》2003,4(6):533-539
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development. 相似文献
36.
Expression cloning of gamma interferon-inducing antigens of Mycobacterium avium subsp. paratuberculosis 下载免费PDF全文
Three recombinant proteins, Map10, Map39, and Map41, produced based on nucleotide sequences obtained from the screening of Mycobacterium avium subsp. paratuberculosis genomic library expressed in Escherichia coli significantly elicited gamma interferon production in peripheral blood mononuclear cells from infected cattle. Two of these proteins were members of the PPE protein family. 相似文献
37.
Satoh Y Ishikawa Y Miyoshi T Mukai H Okumura S Nakagawa K 《Virchows Archiv : an international journal of pathology》2003,442(2):173-178
Pulmonary metastasis from low-grade endometrial stromal sarcomas (ESSs) occasionally are found after long, disease-free periods, mostly as incidental histological or radiological discoveries. We describe a case of low-grade ESS presenting as nodular pulmonary metastases finally diagnosed by estrogen-receptor staining, cytogenetic and fluorescence in situ hybridization (FISH) analyses, and perusal of the histology of hysterectomy material. An abnormal nodule in the lung field was discovered by means of chest X-ray of a 47-year-old woman. She had been disease free for 13 years after hysterectomy for an alleged leiomyoma. A computed tomographic scan revealed nodules, with fluctuation in size over the 2-year period, in both lungs. Finally the lesion in the left lung was resected, and pulmonary endometriosis was suspected because of the lack of stromal cell nuclear atypia and positive immunohistochemical reactions for estrogen and progesterone receptors. However, a characteristic karyotype was identified cytogenetically: 46, XX, t(7;17)(p15;q11), the translocation of which, specific to ESS, was confirmed by FISH analysis. A final diagnosis of pulmonary metastases from an ESS could be made by reviewing the histology of the previous uterine tumor. In this case, metastatic lesions from an ESS showed a decrease as well as an increase in size, despite the malignant potential. Immunostaining for estrogen and progesterone receptors and cytogenetic and FISH analyses, together with clinical information on the past gynecological history, are valuable diagnostic keys. 相似文献
38.
39.
Recombinant tumor necrosis factor alpha does not inhibit the growth of African trypanosomes in axenic cultures 下载免费PDF全文
Kitani H Black SJ Nakamura Y Naessens J Murphy NB Yokomizo Y Gibson J Iraqi F 《Infection and immunity》2002,70(4):2210-2214
Mice whose tumor necrosis factor alpha (TNF-alpha) genes were disrupted developed higher levels of parasitemia than wild-type mice following infection with Trypanosoma congolense IL1180 or T. brucei brucei GUTat3.1, confirming the results of earlier studies. To determine whether TNF-alpha directly affects the growth of these and other bloodstream forms of African trypanosomes, we studied the effects of recombinant mouse, human, and bovine TNF-alpha on the growth of two isolates of T. congolense, IL1180 and IL3338, and two isolates of T. brucei brucei, GUTat3.1 and ILTat1.1, under axenic culture conditions. The preparations of recombinant TNF-alpha used were biologically active as determined by their capacity to kill L929 cells. Of five recombinant TNF-alpha lots tested, one lot of mouse TNF-alpha inhibited the growth of both isolates of T. brucei brucei and one lot of bovine TNF-alpha inhibited the growth of T. brucei brucei ILTat1.1 but only at very high concentrations and without causing detectable killing of the parasites. The other lots of mouse recombinant TNF-alpha, as well as human TNF-alpha, did not affect the growth of any of the test trypanosomes even at maximal concentrations that could be attained in the culture systems (3,000 to 15,000 U of TNF-alpha/ml of medium). These results suggest that exogenously added recombinant TNF-alpha generally does not inhibit the growth of African trypanosomes under the culture conditions we used. The impact of TNF-alpha on trypanosome parasitemia may be indirect, at least with respect to the four strains of trypanosomes reported here. 相似文献
40.
Kawakubo Y Kishimoto H Sato Y Yanagimoto K Tsuruta T Ogawa Y Kameya T 《Virchows Archiv : an international journal of pathology》1999,434(2):109-115
Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing
that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus
(HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected
in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In
situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was
performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV
by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV
infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection
and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in
normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated
with HCMV infection.
Received: 24 November 1998 / Accepted: 24 April 1998 相似文献