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61.
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   
62.
BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability.  相似文献   
63.
64.
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   
65.
Summary Restriction fragment length polymorphisms (RFLPs) of the CYP11B1 gene were studied in Japanese using cDNA clone P450c11 as a probe. Genomic DNAs from 60 unrelated Japanese individuals were digested with 8 different restriction enzymes and analyzed by Southern blot hybridization. Two RFLPs were detected inMspI digests of the DNA. One(A) was characterized by polymorphic bands at 3.4 and 2.5 kilobasepairs (kb) and the other (B) by polymorphic bands at 1.7 and 1.2 kb. The third RFLP was observed inPvuII-digested samples and was polymorphic at 5.8 and 4.0 kb bands. Two of the three RFLPs found, RFLP (A) and (C), have not been described in the only previous report which was based on Caucasian samples. We also examined the RFLPs of a 3 generation family of 11-hydroxylase deficiency caused by an abnormality of the CYP11B1 gene. All the family members were homozygous in all three RFLPs and was thus not informative.  相似文献   
66.
The purpose of this study was to elucidate the effect of raised body temperature per se during acute heat stress on the spontaneous arterial baroreflex control of heart rate (f c) in humans. To investigate whether unloading of cardiopulmonary baroreceptors during whole-body heating would alter the arterial baroreflex control of f c, we controlled loading of the cardiopulmonary baroreceptors by head-down tilt (HDT) at angles of 5°, 10°, 15°, and 30° during heat stress produced by hot-water-perfused suits. The sensitivity of the arterial baroreceptor-cardiac reflex was calculated from the spontaneous changes in beat-to-beat arterial pressure and f c. As an index of cardiopulmonary baroreceptor loading, the left atrial diameter (LAD) was measured by echocardiography. During whole-body heating, the LAD decreased with the rising body core temperature and increased with the HDT. The decreased LAD during heating almost recovered to the normothermic control level by 10° HDT. In the supine position, cardiac baroreflex sensitivity remained unchanged during heating. Arterial pressure, f c and cardiac baroreflex sensitivity were not changed by HDT ranging from 5° to 30° during heating. These results suggest that cardiac baroreflex sensitivity remain unchanged during graded loading of the cardiopulmonary baroreceptors in heat-stressed humans. Also, we conclude that the sensitivity of the spontaneous arterial baroreflex controlling the f c is not influenced by raised body temperature per se during acute heat stress. Electronic Publication  相似文献   
67.
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   
68.
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   
69.
The existence of a mycoplasmal arginine deiminase which catalyzes the conversion of L-arginine to L-citrulline has been postulated. Here we show the partial amino acid sequence of arginine deiminase of Mycoplasma arginini and the complete nucleotide sequence of the arginine deiminase gene of M. arginini. The open reading frame deduced from this sequence consists of 1,230 bp encoding 410 amino acids. The mature form of this enzyme contains 409 amino acids after the deletion of the first methionine. In this open reading frame, TGA nonsense codons are used as tryptophan codons; this usage was verified by determination of the amino acid sequence. The molecular weight of the enzyme calculated from the deduced amino acid sequence is 46,372. Recently, the nucleotide sequence of the arginine deiminase gene of M. arginini was reported by Kondo et al. (K. Kondo, H. Sone, H. Yoshida, T. Toida, K. Kanatani, Y.-M. Hong N. Nishino, and J. Tanaka, Mol. Gen. Genet. 221:81-86, 1990). However, their sequence differed from ours in several places and especially at the C terminus.  相似文献   
70.
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