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61.
K. Higashimoto K. Jozaki T. Kosho K. Matsubara T. Fuke D. Yamada H. Yatsuki T. Maeda Y. Ohtsuka K. Nishioka K. Joh H. Koseki T. Ogata H. Soejima 《Clinical genetics》2014,86(6):539-544
The IGF2/H19‐imprinting control region (ICR1) functions as an insulator to methylation‐sensitive binding of CTCF protein, and regulates imprinted expression of IGF2 and H19 in a parental origin‐specific manner. ICR1 methylation defects cause abnormal expression of imprinted genes, leading to Beckwith–Wiedemann syndrome (BWS) or Silver–Russell syndrome (SRS). Not only ICR1 microdeletions involving the CTCF‐binding site, but also point mutations and a small deletion of the OCT‐binding site have been shown to trigger methylation defects in BWS. Here, mutational analysis of ICR1 in 11 BWS and 12 SRS patients with ICR1 methylation defects revealed a novel de novo point mutation of the OCT‐binding site on the maternal allele in one BWS patient. In BWS, all reported mutations and the small deletion of the OCT‐binding site, including our case, have occurred within repeat A2. These findings indicate that the OCT‐binding site is important for maintaining an unmethylated status of maternal ICR1 in early embryogenesis. 相似文献
62.
Joongho Joh Alfred B. Jenson Arvind Ingle John P. Sundberg Shin-je Ghim 《Experimental and molecular pathology》2014
Correctly folded virus-like particles (VLPs) of papillomavirus (PV) display conformationally dependent epitopes that are type specific, maintained on authentic virions, and induce neutralizing antibodies. Alignment of the L1 amino acid (aa) sequences of 84 PVs revealed that the lengths of their N-termini are diverse and that multiple, possible initiation methionine (met) codons exist. The L1 gene of MusPV (MmuPV1), that naturally infects immunodeficient laboratory mouse strain (NMRI-Foxn1nu/Foxn1nu), has four met codons at the 1st, 2nd, 28th, and 30th aas from its N-terminus. Of these, the 3rd and 4th mets, that are at the 28th and 30th aa position from the N-termius, respectively, are located at the position where most PVs have their first met. These two mets, located at the 9th and 11th from the YLPP conserved aas of most PVs, should be considered as consensus initiation codons of PV L1s. Three L1 proteins of MusPV, starting from the 2nd, 3rd, and 4th mets, were expressed using a baculovirus expression system and characterized for their ability to self-assemble into VLPs. While MusPV L1 proteins starting from the 2nd met expressed an L1 protein that did not fold into VLPs, the L1s starting from the 3rd and 4th mets generated correct VLPs in abundant quantities. We now conclude that the highest quantity and best quality VLPs are made from the consensus L1 met of MusPV. 相似文献
63.
Eun-Ha Joh In-Ah Lee Sang-Jun Han SunJu Chae Dong-Hyun Kim 《International journal of colorectal disease》2010,25(5):545-551
Purpose
In a preliminary study, we found that lancemaside A, which is a main constituent of Codonopsis lanceolata used as an herbal medicine for inflammatory diseases, potently inhibits lipopolysaccharide (LPS)-stimulated, TLR-4-linked NF-κB activation of NF-κB luciferase reporter gene-transfected 293-hTLR4-hemagglutinin (HA) cells. Therefore, we investigated its inhibitory effect in 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in mice. 相似文献64.
Angiogenesis facilitated by autologous whole bone marrow stem cell transplantation for Buerger's disease 总被引:3,自引:0,他引:3
Kim DI Kim MJ Joh JH Shin SW Do YS Moon JY Kim NR Lim JE Kim AK Eo HS Kim BS Cho SW Yang SH Park CJ Shim JS 《Stem cells (Dayton, Ohio)》2006,24(5):1194-1200
We hypothesized that angiogenesis can be triggered by autologous whole bone marrow stem cell transplantation. Twenty-seven patients (34 lower limbs) with Buerger's disease, who were not candidates for surgical revascularization or radiologic intervention, were enrolled in this study. Six sites of the tibia bone were fenestrated using a 2.5-mm-diameter screw under fluoroscopic guidance. Clinical status and outcome were determined using the "Recommended Standards for Reports." To mobilize endothelial progenitor cells (EPCs) from bone marrow, recombinant human granulocyte colony-stimulating factor (r-HuG-CSF) was injected subcutaneously as a dose of 75 microg, preoperatively. During the follow-up period (19.1 +/- 3.5 months), one limb showed a markedly improved outcome (+3), and 26 limbs showed a moderately improved outcome (+2). Thirteen limbs among 17 limbs with nonhealing ulcers healed. Postoperative angiograms were obtained for 22 limbs. Two limbs showed marked (+3), five limbs moderate (+2), and nine limbs slight (+1) collateral development. However, six limbs showed no collateral development (0). Peripheral blood and bone marrow samples were analyzed for CD34 and CD133 molecules to enumerate potential EPCs, and EPC numbers were found to be increased in peripheral blood and in bone marrow after r-HuG-CSF injection. In conclusion, the transplantation of autologous whole BMCs by fenestration of the tibia bone represents a simple, safe, and effective means of inducing therapeutic angiogenesis in patients with Buerger's disease. 相似文献
65.
Lee J Lee EN Kim EY Park HJ Chang CY Jung DY Choi SY Lee SK Lee KW Kwon GY Joh JW Kim SJ 《Immunology letters》2005,101(2):210-216
4-1BB (CDw 137), a member of the tumor necrosis factor receptor (TNFR) superfamily, is a costimulatory receptor primarily expressed on activated T cells. It has been shown that the administration of agonistic anti-4-1BB monoclonal antibody (mAb) enhances tumor immunity and allogenic immune responses. Paradoxically, we found that the administration of anti-4-1BB mAb reduced the incidence and severity of inflammatory bowel disease. In this study, we investigated the effects of anti-4-1BB mAb in a murine intestinal inflammation model, which induced by the hapten reagent, 2,4,6-trinitrobenzene sulfonic acid (TNBS) and mimics immunologic characteristics of human Crohn's disease (CD). Colitis was induced by rectal administration of 2mg of TNBS in 35% ethanol using a vinyl catheter positioned 4cm from the anus. All mice were sacrificed 3 and 10 days after the TNBS administration. The disease activity index (DAI), histological changes of the colon and production of cytokines (IL-2, IL-4, IL-10 and IFN-gamma) were evaluated. The surface molecules of T cells in peripheral blood, spleen and mesenteric lymph nodes were analyzed by flow cytometry. When mice were treated with anti-4-1BB mAb, improvement in both wasting and histopathologic signs of colonic inflammation was observed. The increase a number of splenic CD4(+)CD25(+) T cells and decreased synthesis of the Th1 cytokine IL-2 also occurred. Interestingly, increased production of Th1 cytokine IFN-gamma and proportion of CD8(+) T cells were observed in mice treated with anti-4-1BB mAb in comparison to the colitic mice. These studies show, for the first time, that agonistic anti-4-1BB mAb can improve experimental colitis by reduction of IL-2 and augmentation of CD4(+)CD25(+) regulatory T cells. TNBS colitis is Th1-mediated and has similar histologic features and distribution of inflammation to CD. This study suggests that anti-4-1BB mAb therapy could be effective in the treatment of patients with CD. 相似文献
66.
To explore the epidemiological link between infectious bursal disease virus (IBDV) in wild birds and domestic chickens in Korea, we examined 107 free-living wild birds, representing 7 species, that were found dead of apparent natural causes in Korea over the past two years for the presence of IBDV. Five birds were tested positive for IBDV by RT-PCR assay: black-billed magpie (n=1), mallard duck (n=2), bean goose (n=1) and white-fronted goose (n=1). IBDV was isolated from RT-PCR-positive tissues following chicken embryo inoculation. Sequence analysis of the VP2 gene indicated that all of the isolates from the wild birds encode amino acids A222, I242, I256, I294 and S299 of VP2, which are conserved among strains of very virulent IBDV (vvIBDV). Phylogenetic analysis revealed that the wild bird IBDV isolates are closely related to strains of vvIBDV. An IBDV isolate from a magpie showed 60% mortality in SPF chickens and severe bursal atrophy. The epidemiological implications of IBDV in free-living wild birds are discussed. To our knowledge, this is the first report of vvIBDV in free-living wild birds. 相似文献
67.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
68.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
69.
Venous hemodynamic changes in the surgical treatment of primary varicose vein of the lower limbs 总被引:1,自引:0,他引:1
Venous hemodynamic changes after the surgery of primary varicose veins were evaluated. (Materials and methods) We retrospectively analyzed 1,211 patients (1,407 limbs) who underwent surgery for primary varicose veins from 1994 to 2002. The venous hemodynamics were evaluated using air- plethysmography (APG) preoperatively and one month postoperatively in the viewpoints of ambulatory venous pressure (AVP), venous volume (VV), venous filling index (VFI), and ejection fraction (EF). (Results) The surgical modalities included 958 cases of greater saphenous vein high ligation (GSV HL) and stripping with varicosectomy (VS), 222 cases of short saphenous vein (SSV) HL and VS, 143 cases of external banding valvuloplasty of GSV and VS, and 44 cases using VNUS and VS. The reduction rate of VV was 20.9 +/- 14.1% in the GSV stripping group, 12.0 +/- 14.7% in the GSV valvuloplasty group, 18.3 +/- 16.1% in the VNUS group, and 20.6 +/- 15.9% in the SSV group. The reduction rate of VFI was 63.6 +/- 20.7% in the GSV stripping group, 38.8 +/- 40.9% in the GSV valvuloplasty group, 60.1 +/- 23.9% in the VNUS group, and 37.6 +/- 30.2% in the SSV group. The increasing rate of EF was 25.0 +/- 28.2% in the GSV stripping group, 21.0 +/- 30.0% in the GSV valvuloplasty group, 29.4 +/- 31.9% in the VNUS group, and 30.0 +/- 36.5% in the SSV group. The reduction rate of AVP was 25.4 +/- 32.2% in the GSV stripping group, -6.1 +/- 58.1% in the GSV valvuloplasty group, 28.4 +/- 38.5% in the VNUS group, and 14.1 +/- 49.0% in the SSV group. All of the patients showed improvements in venous hemodynamics by showing a decrease in VV, VFI, AVP, and an increase in EF. However, there was no difference in the change of venous hemodynamics according to the type of surgery. 相似文献
70.
Lowrance D Makombe S Harries A Yu J Aberle-Grasse J Eiger O Shiraishi R Marston B Ellerbrock T Libamba E 《Journal of acquired immune deficiency syndromes (1999)》2007,46(1):56-61
OBJECTIVE: To determine whether Malawi antiretroviral treatment (ART) clinics providing cotrimoxazole (CTX) prophylaxis had lower early mortality rates compared with clinics not providing CTX. METHODS: Retrospective cohort study of eleven ART clinics in Malawi that were or were not providing CTX. Medical record abstraction was performed for all patients (N = 1295) initiating ART between July 1 and December 15, 2005. At 5 ART sites, CTX was given to patients dosed at 960 mg daily or 480 mg twice a day (according to national guidelines). RESULTS: When all defaults (patients lost to follow-up for >90 days) were excluded from the analysis, the 6-month mortality rate was 10.7% in patients receiving ART at CTX clinics compared with 18.0% in those not at CTX clinics (6-month mortality risk reduction = 40.7%; P = 0.0013). Kaplan-Meier survival curves for patients receiving CTX and patients not receiving CTX were significantly different; survival differences were apparent as early as 40 to 45 days after initiation of ART. CONCLUSIONS: Patients receiving ART in Malawi at clinics offering CTX prophylaxis had significantly reduced mortality during the first 6 months of ART. This additional intervention may have the potential to improve the lives of patients on ART, because CTX is readily available and relatively inexpensive and can, in principle, be easily introduced into ART delivery programs. 相似文献