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991.
Chino T Tamai K Yamazaki T Otsuru S Kikuchi Y Nimura K Endo M Nagai M Uitto J Kitajima Y Kaneda Y 《The American journal of pathology》2008,173(3):803-814
Recent studies have shown that skin injury recruits bone marrow-derived fibroblasts (BMDFs) to the site of injury to accelerate tissue repair. However, whether uninjured skin can recruit BMDFs to maintain skin homeostasis remains uncertain. Here, we investigated the appearance of BMDFs in normal mouse skin after embryonic bone marrow cell transplantation (E-BMT) with green fluorescent protein-transgenic bone marrow cells (GFP-BMCs) via the vitelline vein, which traverses the uterine wall and is connected to the fetal circulation. At 12 weeks of age, mice treated with E-BMT were observed to have successful engraftment of GFP-BMCs in hematopoietic tissues accompanied by induction of immune tolerance against GFP. We then investigated BMDFs in the skin of the same mice without prior injury and found that a significant number of BMDFs, which generate matrix proteins both in vitro and in vivo, were recruited and maintained after birth. Next, we performed E-BMT in a dystrophic epidermolysis bullosa mouse model (col7a1−/−) lacking type VII collagen in the cutaneous basement membrane zone. E-BMT significantly ameliorated the severity of the dystrophic epidermolysis bullosa phenotype in neonatal mice. Type VII collagen was deposited primarily in the follicular basement membrane zone in the vicinity of the BMDFs. Thus, gene therapy using E-BMT into the fetal circulation may offer a potential treatment option to ameliorate genetic skin diseases that are characterized by fibroblast dysfunction through the introduction of immune-tolerated BMDFs. 相似文献
992.
Ono R Matsuoka J Yamatsuji T Naomoto Y Tanaka N Matsui H Matsushita M 《International journal of molecular medicine》2008,22(2):199-203
Cell motility is involved in physiological and pathological processes such as the invasion and migration of cells. c-Jun N-terminal kinase (JNK) cascades are involved in the invasion and metastasis of cancer cells. However, little is known about the downstream signaling of JNK. In the present study, we used small interfering RNA (siRNA) directed against JNK1 to reduce its expression. We used microarray techniques to compare the gene expression profiles of epidermal growth factor (EGF)-stimulated HeLa cells with and without JNK1 siRNA treatment. We identified a JNK1 target gene, myosin phosphatase-Rho interacting protein (M-RIP). RNA interference-mediated inhibition of JNK1 strongly inhibited M-RIP mRNA expression induced by EGF, as well as the invasion of HeLa cells. In addition, M-RIP siRNA-treated cells showed significantly reduced invasive activity. Thus, a functional analysis of JNK1 and M-RIP with RNA interference reveals a critical role for this cascade in the invasive behavior of cancer cells. 相似文献
993.
Matsushita H Kobayashi M Tsukiyama R Fujimoto M Suzuki M Tsuji K Yamamoto K 《International journal of molecular medicine》2008,22(2):243-247
Soy sauce (Shoyu) is a traditional Japanese fermented seasoning and is available worldwide. We investigated the effect of Shoyu polysaccharides (SPS) prepared from soy sauce on the intestinal immune system of mice. SPS enhanced the production of immunoglobulin A (IgA) from Peyer's patch cells in vitro, and its oral administration to 7-week-old male BALB/c mice for 2 weeks at a dose of 1.5 mg per day significantly (p<0.01) increased the concentration of IgA in the intestine as compared to control mice. Furthermore, experiments on the intestinal transport of SPS in vitro using the human intestinal epithelial cell line Caco-2 confirmed the permeation of uronic acid to be time-dependent. In conclusion, SPS of soy sauce enhanced the production of IgA in vitro and in vivo, and the digested SPS might cross the enterocytic monolayer. Thus, soy sauce is a potentially promising food for enhancing host defenses. 相似文献
994.
995.
Matsubara T Eimoto T Okabe M Miyabe S Fujiyoshi Y Matsushita Y Mizutani J Yamada S Otsuka T 《Histopathology》2008,52(6):706-716
Aims: To evaluate proliferation and apoptosis in high-grade sarcomas of the extremities before and after preoperative radio-hyperthermo-chemotherapy (RHC) and to determine the relationship between these parameters and treatment outcomes.
Methods and results: Pre- and post-RHC specimens of 41 soft tissue and bone tumours were immunohistochemically stained for minichromosome maintenance protein (MCM) 2 and caspase 3 as proliferation and apoptosis markers, respectively, based on a preliminary study comparing them with conventional markers. Indices were calculated as a percentage of positive cells by counting tumour cells in the most frequently labelled areas. MCM2, caspase 3 and MCM2/caspase 3 (growth) indices were 45.3 ± 21.9%, 4.1 ± 7.1% and 82.9 ± 104.5, respectively, in pre-RHC specimens and 35.4 ± 30.8%, 39.2 ± 34.6% and 5.3 ± 11.7, respectively, in post-RHC specimens. Response scores showed positive correlation with pre-RHC MCM2 and post-RHC caspase 3 indices, inverse correlation with post-RHC MCM2 and post-RHC growth indices and no correlation with prognosis. Multivariate analysis revealed high pre-RHC MCM2 and high post-RHC growth indices as significant unfavourable prognostic factors.
Conclusions: High proliferative activity in untreated sarcoma may predict good response to neoadjuvant therapy, but poor prognosis, whereas a high growth index, i.e. high proliferation:apoptosis ratio in a post-neoadjuvant therapy tumour specimen may indicate poor response and poor prognosis. 相似文献
Methods and results: Pre- and post-RHC specimens of 41 soft tissue and bone tumours were immunohistochemically stained for minichromosome maintenance protein (MCM) 2 and caspase 3 as proliferation and apoptosis markers, respectively, based on a preliminary study comparing them with conventional markers. Indices were calculated as a percentage of positive cells by counting tumour cells in the most frequently labelled areas. MCM2, caspase 3 and MCM2/caspase 3 (growth) indices were 45.3 ± 21.9%, 4.1 ± 7.1% and 82.9 ± 104.5, respectively, in pre-RHC specimens and 35.4 ± 30.8%, 39.2 ± 34.6% and 5.3 ± 11.7, respectively, in post-RHC specimens. Response scores showed positive correlation with pre-RHC MCM2 and post-RHC caspase 3 indices, inverse correlation with post-RHC MCM2 and post-RHC growth indices and no correlation with prognosis. Multivariate analysis revealed high pre-RHC MCM2 and high post-RHC growth indices as significant unfavourable prognostic factors.
Conclusions: High proliferative activity in untreated sarcoma may predict good response to neoadjuvant therapy, but poor prognosis, whereas a high growth index, i.e. high proliferation:apoptosis ratio in a post-neoadjuvant therapy tumour specimen may indicate poor response and poor prognosis. 相似文献
996.
Han XJ Lu YF Li SA Tomizawa K Takei K Matsushita M Matsui H 《Neuroscience research》2008,60(1):114-119
Alterations in the morphology and movement of mitochondria influence neuronal viability. However, the precise mechanisms of such alterations are unclear. In this study, we showed calcineurin was involved in the regulation of mitochondrial dynamics. Glutamate stimulation inhibited mitochondrial movement and decreased mitochondrial length in neurons. FK506 and cyclosporine A, calcineurin inhibitors, attenuated the effects of glutamate on mitochondrial dynamics. It was also found that glutamate treatment dephosphorylated, a proapoptotic protein, Bad and promoted its translocation to mitochondria in neurons via calcineurin. These results provide important new insights into intracellular signaling pathways that regulate mitochondrial dynamics and neuronal cell death. 相似文献
997.
Uchida Y Chaichoune K Wiriyarat W Watanabe C Hayashi T Patchimasiri T Nuansrichay B Parchariyanon S Okamatsu M Tsukamoto K Takemae N Ratanakorn P Yamaguchi S Saito T 《Virus research》2008,138(1-2):70-80
A comprehensive molecular epidemiological analysis was performed on highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype derived from poultry and wild bird during 2004-2007 in Thailand. Sequence analysis followed by phylogenetic analysis was applied to all eight segments of the viruses. Viruses belonging to clades 1 and 2.3.4 in the HA phylogenetic tree have been shown to circulate in Thailand. Our analysis revealed differential evolution of the HPAI viruses among clade 1 strains. Isolates from Phichit province in 2006 resided in two distinct branches, designated 1.p1 and 1.p2. A hemagglutination inhibition test with a panel of monoclonal antibodies demonstrated a possible antigenic drift between the Phichit isolates. Involvement of free-grazing duck practice in the area was discussed as a cause of the differential evolution among the Phichit isolates. A branch, designated 1-TGWB and consisting exclusively of isolates from zoological tigers and wild birds, was evident in all phylogenetic trees constructed in the study. The branch's existence indicated that the HPAI viruses could have been maintained in the wild bird population for a certain period, although no involvement of wild birds in HPAI transmission to poultry was evident in this study. 相似文献
998.
Distribution of HLA alleles and haplotypes in Jinuo and Wa populations in Southwest China 总被引:1,自引:0,他引:1
Shi L Ogata S Yu JK Ohashi J Yu L Shi L Sun H Lin K Huang XQ Matsushita M Horai S Muramatsu M Chu JY Tokunaga K 《Human immunology》2008,69(1):58-65
The frequencies of human leukocyte antigen (HLA) alleles HLA-A, -B, and -DRB1 alleles and A-B-DRB1, A-B, and B-DRB1 haplotypes were studied in Jinuo and Wa populations in Southwest China using the polymerase chain reaction-Luminex (PCR-Luminex) typing method. A total of 12 A, 22 B, and 16 DRB1 alleles were found in the Jinuo population, and 10 A, 28 B, and 18 DRB1 alleles were found in the Wa population. The A*110101-B*1502-DRB1*120201 was the predominant haplotype in both the Jinuo and Wa populations; A*110101-B*1301-DRB1*120201 and A*24020101-B*1502-DRB1*120201 were common in the Jinuo population, whereas A*110101-B*1532-DRB1*1504 and A*110101-B*350101-DRB1*1404 were common in the Wa population. Phylogenetic tree and principal component analyses based on HLA-A, -B, and -DRB1 allele frequencies suggested that both the Jinuo and Wa populations belong to the Southeast Asian group, whereas Wa population is still maintaining its original genetic character and a great distance from other populations because of a founder effect and subsequent geographic isolation. A close relationship among Jinuo, Wa, Thai, and Vietnamese was also suggested. 相似文献
999.
To explore the brain response to sacral surface therapeutic electrical stimulation (SSTES) for the treatment of refractory urinary incontinence and frequent micturition, evoked magnetic fields were measured in six healthy males. Electrical stimuli were applied between bilateral surface electrodes over the second through fourth posterior sacral foramens with intensity just below the pain threshold. Somatosensory evoked magnetic fields (SEFs) for the bilateral median (MN) and posterior tibial nerves (PTN) were also measured for the comparison. Sources of the early SEF peaks were superimposed on individual magnetic resonance images. The first peak latency for sacral stimuli, M30, occurred at 30.2+/-0.8 ms (mean+/-standard deviation, N=6), with shorter latency than those for PTN stimulus (39.3+/-1.4 ms, N=12) and longer latency than those for MN stimulus (21.0+/-0.9 ms, N=12). The second peak latency for sacral stimuli, M50, occurred at 47.2+/-2.9 ms (N=6). Both M30 and M50 peaks showed a single dipole pattern over the vertex in the isofield maps. The equivalent current dipoles of M30 and M50 were both estimated near the medial end of the central sulcus with approximately posterior current direction. These results suggest that the sacral M30 and M50 are responses from the primary somatosensory cortex. The relatively long time lag between the onset and peak of M30 suggests that SSTES directly affects both the cauda equina and cutaneous nerve of the sacral surface. 相似文献
1000.
Miki Nishio Koichi Hamada Kohichi Kawahara Masato Sasaki Fumihito Noguchi Shuhei Chiba Kensaku Mizuno Satoshi O. Suzuki Youyi Dong Masaaki Tokuda Takumi Morikawa Hiroki Hikasa Jonathan Eggenschwiler Norikazu Yabuta Hiroshi Nojima Kentaro Nakagawa Yutaka Hata Hiroshi Nishina Koshi Mimori Masaki Mori Takehiko Sasaki Tak W. Mak Toru Nakano Satoshi Itami Akira Suzuki 《The Journal of clinical investigation》2012,122(12):4505-4518
Mps one binder 1a (MOB1A) and MOB1B are key components of the Hippo signaling pathway and are mutated or inactivated in many human cancers. Here we show that intact Mob1a or Mob1b is essential for murine embryogenesis and that loss of the remaining WT Mob1 allele in Mob1aΔ/Δ1btr/+ or Mob1aΔ/+1btr/tr mice results in tumor development. Because most of these cancers resembled trichilemmal carcinomas, we generated double-mutant mice bearing tamoxifen-inducible, keratinocyte-specific homozygous-null mutations of Mob1a and Mob1b (kDKO mice). kDKO mice showed hyperplastic keratinocyte progenitors and defective keratinocyte terminal differentiation and soon died of malnutrition. kDKO keratinocytes exhibited hyperproliferation, apoptotic resistance, impaired contact inhibition, enhanced progenitor self renewal, and increased centrosomes. Examination of Hippo pathway signaling in kDKO keratinocytes revealed that loss of Mob1a/b altered the activities of the downstream Hippo mediators LATS and YAP1. Similarly, YAP1 was activated in some human trichilemmal carcinomas, and some of these also exhibited MOB1A/1B inactivation. Our results clearly demonstrate that MOB1A and MOB1B have overlapping functions in skin homeostasis, and exert their roles as tumor suppressors by regulating downstream elements of the Hippo pathway. 相似文献