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31.
Fujita K Tsujimura A Takao T Miyagawa Y Matsumiya K Koga M Takeyama M Fujioka H Aozasa K Okuyama A 《Human reproduction (Oxford, England)》2005,20(8):2289-2294
BACKGROUND: Microdissection testicular sperm extraction (TESE) has provided new hope for successful sperm retrieval to patients with Sertoli cell-only syndrome (SCO). We determined expression of the inhibin alpha subunit, glial cell line-derived neurotrophic factor (GDNF) and stem cell factor (SCF) in Sertoli cells obtained from patients with SCO immunohistochemically and compared expression rates with rates of microdissection TESE sperm retrieval. METHODS: Testicular biopsy specimens were obtained from 52 men with non-obstructive azoospermia who underwent microdissection TESE and were diagnosed with SCO by histological analysis. RESULTS: All specimens showed intense staining for the inhibin alpha subunit. Moderate or intense staining for GDNF was observed in 65.8% of specimens. All but one showed moderate or intense staining for SCF. Among specimens negative for GDNF, the sperm retrieval rate was significantly higher (100%) for specimens with intense staining for SCF than for specimens with no or moderate staining (30.7%) (P<0.05) for SCF. CONCLUSION: GDNF expression differs among patients with SCO. The sperm retrieval rate was high in cases of no staining for GDNF and intense staining for SCF. 相似文献
32.
Suzuki M Okuyama T Yoshikawa K Yamaoka Y Ariyasu T Fujita M Tankawa H Sugiyama T Takahashi R 《Pathology international》1996,46(1):46-53
Overexpression of p53 protein, epidermal growth factor receptor (EGF-R), and c-erbB-2 protein was assessed by immunohistochemical staining of formalin-fixed, paraffin-embedded tissue from 64 invasive breast tumors. The correlation between abnormal expression of each protein and various disease parameters, including lymph node metastasis and histopathologic type and grade was analyzed. Despite the previous proposal, no significant correlation was found between lymph node metastases and overexpression of each gene in the primary tumors. In addition, some metastatic lesions did not always exhibit overexpression, even if it was evident in the primary tumors. Overexpression of c-erbB-2 protein correlated well with Bloom's histological grading. p53 expression was detected most often in tumors with hyperchromatism and more frequent mitosis. Overexpression of c-erbB-2 protein occurred more frequently in p53-positive tumors. The results indicate that abnormal expression of p53 protein causes genetic instability in the early stage of tumor development, resulting in subsequent overexpression of other oncogenes. 相似文献
33.
Kazutaka Suga Minori Saitoh Satoshi Kokubo Kazutoshi Nozaki Shinji Fukushima Shuhei Yasuda Masao Sasamata Keiji Miyata 《Journal of interferon & cytokine research》2004,24(6):343-349
Recombinant human interleukin-11 (rHuIL-11) and recombinant human bone morphogenetic protein-2 (rHuBMP-2) have been shown to act synergistically in the induction of osteoblast differentiation. To determine whether these two proteins can be used clinically in fracture healing and reconstructive surgery, we investigated whether rHuIL-11 and rHuBMP-2 act synergistically to heal segmental bone defects in a rabbit model. A 1.5-cm segmental defect was created in the right ulnar diaphysis of 20 Japanese white rabbits. Polylactic-co-glycolic acid (PLGA)-coated gelatin sponges (PGS) permeated with rHuBMP-2 (n = 8), rHuIL-11 plus rHuBMP-2 (n = 8), or rHuIL-11 (n = 4) were implanted into the bone defects. Radiographs were scored by two independent observers for bone formation and union rates after 2, 3, 4, and 8 weeks. Bone formation was higher in rabbits implanted with rHuBMP-2 plus rHuIL-11 than in those implanted with rHuBMP-2 alone, reaching statistical significance after 4 weeks. At early time points, the union rate in rabbits implanted with rHuBMP-2 plus rHuIL-11 was higher than in rabbits implanted with rHuBMP-2. At 2, 4, and 8 weeks, new bone volume was significantly higher in rabbits administered rHuIL-11 plus rHuBMP-2 than in those given rHuBMP-2 alone. In contrast, mechanical testing after 8 weeks showed that bone strength in the two groups of rabbits was equivalent. These findings show that rHuIL-11 and rHuBMP-2 act synergistically to accelerate bone formation without affecting bone strength. Treatment with a combination of rHuIL-11 and rHuBMP-2 may thus be of great benefit in fracture healing and for patients undergoing reconstructive surgery. 相似文献
34.
Single nucleotide polymorphisms in the protamine-1 and -2 genes of fertile and infertile human male populations 总被引:6,自引:0,他引:6
Tanaka H Miyagawa Y Tsujimura A Matsumiya K Okuyama A Nishimune Y 《Molecular human reproduction》2003,9(2):69-73
Although various genetic factors have been implicated in human male infertility, the causative genes for the different types of idiopathic male infertility have not been elucidated. Protamines, which are the major DNA-binding proteins in the sperm nucleus, package the DNA into the sperm head. Analysis of the human protamine-1 (PRM1) and -2 (PRM2) gene sequences in 226 sterile male patients and in 270 proven-fertile male volunteers revealed four single nucleotide polymorphisms (SNPs) in the PRM1 coding region, which did not cause any amino acid substitutions, and one SNP in the PRM2 gene, which produced translation termination. We also observed one SNP in the 3' non-coding region of the PRM1 gene, and two SNPs within the intron of the PRM2 gene. The prevalence of these SNPs was similar in both infertile patients and in proven-fertile volunteers, except that the c248t alteration in the PRM2 gene induced a nonsense codon under conditions of heterozygosity in one infertile patient. Although the PRM1 and PRM2 genes are highly conserved, the single SNP in the PRM2 gene that induces translation termination may result in male infertility due to haploinsufficiency of PRM2. 相似文献
35.
Repair of infarcted myocardium mediated by transplanted bone marrow-derived CD34+ stem cells in a nonhuman primate model 总被引:6,自引:0,他引:6
Yoshioka T Ageyama N Shibata H Yasu T Misawa Y Takeuchi K Matsui K Yamamoto K Terao K Shimada K Ikeda U Ozawa K Hanazono Y 《Stem cells (Dayton, Ohio)》2005,23(3):355-364
Rodent and human clinical studies have shown that transplantation of bone marrow stem cells to the ischemic myocardium results in improved cardiac function. In this study, cynomolgus monkey acute myocardial infarction was generated by ligating the left anterior descending artery, and autologous CD34(+) cells were transplanted to the peri-ischemic zone. To track the in vivo fate of transplanted cells, CD34(+) cells were genetically marked with green fluorescent protein (GFP) using a lentivirus vector before transplantation (marking efficiency, 41% on average). The group receiving cells (n = 4) demonstrated improved regional blood flow and cardiac function compared with the saline-treated group (n =4) at 2 weeks after transplant. However, very few transplanted cell-derived, GFP-positive cells were found incorporated into the vascular structure, and GFP-positive cardiomyocytes were not detected in the repaired tissue. On the other hand, cultured CD34(+) cells were found to secrete vascular endothelial growth factor (VEGF), and the in vivo regional VEGF levels showed a significant increase after the transplantation. These results suggest that the improvement is not the result of generation of transplanted cell-derived endothelial cells or cardiomyocytes; and raise the possibility that angiogenic cytokines secreted from transplanted cells potentiate angiogenic activity of endogenous cells. 相似文献
36.
Seminoma in a postmenopausal woman with a Y;15 translocation in peripheral blood lymphocytes and a t(Y;15)/45,X Turner mosaic pattern in skin fibroblasts.
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N Hoshi M Fujita M Mikuni T Fujino K Okuyama Y Handa H Yamada T Sagawa H Hareyama Y Nakahori K Fujieda J A Kant K Nagashima S Fujimoto 《Journal of medical genetics》1998,35(10):852-856
We report an unusual case of a 55 year old Japanese woman with a seminoma but relatively normal menses. The patient was a phenotypic female with late onset menarche (18 years of age), who was amenorrhoeic for the first year, followed by menses of one to three days' slight flow with dysmenorrhoea, but an otherwise normal menstrual history. A typical seminoma was removed from the left adnexal region and an immature testis was identified separately as an associated right adnexal mass. Repeated karyotypic studies on peripheral blood lymphocyte cultures showed only 46,X,-Y,t(Y;15)(q12;p13). Cytogenetic examination of the patient's younger brother, who had fathered three healthy children, showed an identical karyotype. Mosaicism of 46,X,-Y,t(Y;15)(q12;p13)/45,X cell lines was found in skin samples from the patient's elbow and genital regions, although there were no clinical stigmata of Turner syndrome. An androgen receptor binding assay of cultured genital skin fibroblasts was negative. Molecular analysis using Southern blot hybridisation, PCR, and direct DNA sequencing showed that neither the patient nor her brother had a detectable deletion or other abnormalities of Y chromosome sequences, including the SRY (sex determining region of the Y chromosome) gene sequence. These findings suggest that Turner mosaicism of the 45,X cell line may have contributed to this atypical presentation in an XY female, although we cannot exclude abnormalities of other genes related to sex differentiation. 相似文献
37.
Preferential expression of RB1-inducible coiled-coil 1 in terminal differentiated musculoskeletal cells
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RB1-inducible coiled-coil 1 (RB1CC1) is a nuclear DNA-binding protein that can induce RB1 (retinoblastoma 1) expression. RB1CC1 is abundantly expressed in human musculoskeletal and cultured osteosarcoma cells. The present study analyzed the expression of RB1CC1 and RB1 in osteosarcoma cells and in musculoskeletal cells of human embryos to evaluate the contribution of both genes to the maturational process of musculoskeletal cells. The amount of RB1CC1 message was closely related to RB1 expression in various osteosarcoma cell lines. RB1CC1 expression was difficult to detect in immature proliferating chondroblasts or myogenic cells in human embryos, but became obvious and prominent concomitantly with the maturation of osteocytes, chondrocytes, and skeletal muscle cells. RB1CC1 expression in these musculoskeletal cells increased with RB1 expression, which is linked to the terminal differentiation of many tissues and cells. In addition, the introduction of wild-type RB1CC1 decreased the formation of macroscopic colonies in the cell growth assay. Accordingly, both RB1CC1 and RB1 genes preferentially co-expressed and contributed to the maturation of human embryonic musculoskeletal cells, and may regulate the proliferative activity and maturation of tumor cells derived from these tissues. 相似文献
38.
Yuji Okuyama Mitsuhiko Yamada Chikako Kondo Eisaku Satoh Shojiro Isomoto Takashi Shindo Yoshiyuki Horio Masafumi Kitakaze Masatsugu Hori Y. Kurachi 《Pflügers Archiv : European journal of physiology》1998,435(5):595-603
The effects of potassium channel opening drugs and intracellular nucleotides on the ATP-sensitive K+ (KATP) channel composed of SUR2A and Kir6.2 in HEK293T cells were examined using the patch-clamp technique. The SUR2A/Kir6.2 channel
was activated effectively by pinacidil, marginally by nicorandil but not by diazoxide. The pinacidil-activated channel currents
were inhibited by glibenclamide with a K
i value of 160 nM. Upon formation of inside-out (I-O) patches, spontaneous openings of the channels appeared, which were inhibited
by intracellular ATP (ATPi) equipotently in the presence and in the absence of intracellular Mg2+ (Mg2+
i). The channel activity ran-down gradually in I-O patches. The run-down channels could be reactivated by ATPi only in the presence of Mg2+
i. Uridine 5’-diphosphate (UDP) antagonized the ATPi-mediated inhibition of the channel activity before run-down. After run-down, UDP activated the channel without antagonizing
ATPi-mediated channel inhibition. Thus, the SUR2A/Kir6.2 reproduced the major properties of the native cardiac KATP channel well in terms of nucleotide regulation and pharmacology, and therefore can be a useful tool with which to elucidate
the molecular mechanisms characterizing the KATP channel.
Received: 24 October 1997 / Received after revision and accepted: 4 December 1997 相似文献
39.
Enkhtuvshin Gereltzul Yoshiyuki Baba Naoto Suda Momotoshi Shiga Maristela Sayuri Inoue Michiko Tsuji Insik Shin Yukio Hirata Kimie Ohyama Keiji Moriyama 《Journal of human genetics》2008,53(10):941-946
This is a report of a 27-year-old woman with an unusual de novo chromosomal abnormality. Mosaicism was identified in peripheral
blood cells examined by standard G-bands by trypsin using Giemsa (GTG) analysis and fluorescence in situ hybridization (FISH)
analysis with chromosome-18 region-specific probes, 46,XX,del(18)(pter → q21.33:)[41], 46,XX,r(18)(::p11.21 → q21.33::)[8],
and 46,XX,der(18)(pter → q21.33::p11.21 → pter)[1]. On the other hand, the karyotype of periodontal ligament fibroblasts was
nonmosaic, 46,XX, der(18)(pter → q21.33::p11.21 → pter)[50]. All cell lines appeared to be missing a portion of 18q (q21.33 → qter).
The pattern of the dup(18p)/del(18q) in the rod configuration raises the possibility of an inversion in chromosome 18 in one
of the parents. However, no chromosomal anomaly was detected in either parent. The most probable explanation is that de novo
rod and ring configurations arose simultaneously from an intrachromosomal exchange. The unique phenotype of this patient,
which included primary hypothyroidism and primary hypogonadism, is discussed in relation to her karyotype. 相似文献
40.
Yasutake Saekt Kouichi Shiozawa Cheol -Ho Paik Keiji Yanagisawa 《Journal of muscle research and cell motility》1991,12(2):152-160
Summary To clarify the activation-dependence of dynamic mechanical characteristics of contracting cardiac muscle, we analysed the healthy central segment length (SL) response to step decrease in tension at two different levels of barium contracture (0.2 mM and 0.5 mM Ba2+) in rat papillary muscles with a fixed initial SL. The time course of this response is thought to reflect the kinetics of actin-myosin interaction. The muscle was released stepwise from the steady contracture tension (Tc) to new steady tension levels (Tr) of varying magnitudes at 22° C. The SL responses consisted of four phases at Tr/Tc > 0.3. The amplitude of shortening in the second phase, after the initial rapid and minute shortening in the first phase, increased with an increase in amplitude of step tension reduction, and was greater at the higher activation level when compared at an identical amount of Tr/Tc. The fourth phase, after the remarkable lengthening in the third phase, was an extremely slow and minute shortening toward a new steady SL under the new tension. The duration of the second and third phase was quite insensitive to activation level at Tr/Tc > 0.85, but became longer at the higher activation level with larger amounts of tension reduction. The velocity measured from the initial quasi-steady SL shortening in the second phase increased significantly with the increase in activation level. These results are discussed in terms of cross-bridge kinetics underlying the isotonic SL transients at two different activation levels. 相似文献