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991.
Ken Yasukawa Michio Takido Mieko Takeuchi Michinori Akasu Shigeki Nakagawa 《Journal of cancer research and clinical oncology》1991,117(5):421-424
Summary Cepharanthine, isolated fromStephania cepharantha, is one of the bisbenzylisoquinoline-type alka-loids. We have found that it inhibits tumor promotion after topical application in two-stage carcinogenesis in mouse skin. Epidermal ornithine decarboxylase activities inhibited by topical application of cepharanthine, with an 5 g/mouse) and mezerein (5 g/mouse) were found to be inhibited by topical application of cepharanthine, with a ED50 of 1.2 mol and 1.4 mol respectively. These inhibitory effects of cepharanthine are considered to be related to its antitumor activity in two-stage carcinogenesis in mouse skin. Cell-mediated immunosuppression by TPA was unaffected by topical application of cepharanthine. A diet containing 0.005% cepharanthine (about 0.5 mg mouse– day–) slightly suppressed the two-stage promotion of skin tumors by twice-weekly applications of 2.5 g TPA for 2 weeks (first stage) followed by twice-weekly applications of 2.5 g mezerein for 23 weeks (second stage) in ICR mice following initiation by 50 g 7,12-dimethylbenz[a]anthracene. Oral administration of cepharanthine inhibits the tumor promotion in two-stage carcinogenesis in mouse skin.Abbreviations DMBA
7,12-dimethylbenz[a]anthracene
- DTH
delayed-type hypersensitivity
- ODC
ornithine decarboxylase
- TPA
12-O-tetradecanoylphorbol 13-acetate 相似文献
992.
Insulin and insulin-like growth factor-I acutely inhibit surface translocation of growth hormone receptors in osteoblasts: A novel mechanism of growth hormone receptor regulation 下载免费PDF全文
Kin-Chuen Leung Michael J. Waters Irit Markus William R. Baumbach Ken K. Y. Ho 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(21):11381-11386
We previously have demonstrated that insulin and insulin-like growth factor-I (IGF-I) down-regulate growth hormone (GH) binding in osteoblasts by reducing the number of surface GH receptors (GHRs). The present study was undertaken to investigate the mechanism of GHR down-regulation. Treatment with 5 nM insulin or IGF-I for 18 hr significantly decreased surface GH binding to 26.4 ± 2.9% and 23.0 ± 2.7% of control (mean ± SE; P < 0.05), respectively. No corresponding reductions in the mRNA level and total cellular content of GHR were found, nor was the rate of receptor internalization affected. The effects on GHR translocation were assessed by measuring the reappearance of GH binding of whole cells after trypsinization to remove the surface receptors. GH binding of control cultures significantly increased (P < 0.05) over 2 hr after trypsinization, whereas no recovery of binding activity was detected in insulin and IGF-I-treated cultures, indicating that GHR translocation was impaired. Studies on the time course of GHR down-regulation revealed that surface GH binding was reduced significantly by 3-hr treatment (P ≤ 0.0005), whereas GHR translocation was completely abolished by 75–90 min with insulin and IGF-I. The inhibition of receptor translocation by insulin, but not IGF-I, was attenuated by wortmannin. In conclusion, insulin and IGF-I down-regulated GH binding in osteoblasts by acutely impairing GHR translocation, with their effects exerted through distinct postreceptor signaling pathways. 相似文献
993.
Takai K Nakamura K Toki T Tsunogai U Miyazaki M Miyazaki J Hirayama H Nakagawa S Nunoura T Horikoshi K 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(31):10949-10954
We have developed a technique for cultivation of chemolithoautotrophs under high hydrostatic pressures that is successfully applicable to various types of deep-sea chemolithoautotrophs, including methanogens. It is based on a glass-syringe-sealing liquid medium and gas mixture used in conjunction with a butyl rubber piston and a metallic needle stuck into butyl rubber. By using this technique, growth, survival, and methane production of a newly isolated, hyperthermophilic methanogen Methanopyrus kandleri strain 116 are characterized under high temperatures and hydrostatic pressures. Elevated hydrostatic pressures extend the temperature maximum for possible cell proliferation from 116°C at 0.4 MPa to 122°C at 20 MPa, providing the potential for growth even at 122°C under an in situ high pressure. In addition, piezophilic growth significantly affected stable carbon isotope fractionation of methanogenesis from CO2. Under conventional growth conditions, the isotope fractionation of methanogenesis by M. kandleri strain 116 was similar to values (−34‰ to−27‰) previously reported for other hydrogenotrophic methanogens. However, under high hydrostatic pressures, the isotope fractionation effect became much smaller (<−12‰), and the kinetic isotope effect at 122°C and 40 MPa was −9.4‰, which is one of the smallest effects ever reported. This observation will shed light on the sources and production mechanisms of deep-sea methane. 相似文献
994.
Kimura K Miura H Saito S Suzaki A Kondo K Hamada T Kitamura S Yamada H 《Internal medicine (Tokyo, Japan)》2008,47(7):671-674
A 54-year-old man had undergone transcatheter arterial embolization (TAE) three times to treat hepatitis B virus-related hepatocellular carcinoma (HCC), but recurrence was found in June 2005. A large tumor in the left lateral portion of the liver showed extrahepatic growth and was attached to the gastric wall. TAE was performed a forth time. In September 2005, the patient was admitted with worsening anemia. Computed tomography and upper gastrointestinal endoscopy revealed that the HCC had directly invaded the stomach and caused gastrointestinal hemorrhage. Endoscopic hemostasis was effective, but the patient died because of worsening hepatic failure. 相似文献
995.
Yutaka Terada Shohei Minami Keita Noguchi Hassan Y.A.H. Mahmoud Hiroshi Shimoda Masami Mochizuki Yumi Une Ken Maeda 《Emerging infectious diseases》2014,20(2):284-287
We detected ferret coronaviruses in 44 (55.7%) of 79 pet ferrets tested in Japan and classified the viruses into 2 genotypes on the basis of genotype-specific PCR. Our results show that 2 ferret coronaviruses that cause feline infectious peritonitis–like disease and epizootic catarrhal enteritis are enzootic among ferrets in Japan. 相似文献
996.
Kath Padgett BSc MA PGDip Cert Ed RMN Christine Rhodes BSc MSc RGN RM RN Child RHV Maureen Lumb Penny Morris BA Sue Sherwin BA MA PGCHE RMN Jools Symons BA MA Joannie Tate Ken Townend 《Health expectations》2014,17(3):418-428
Background Involving service users and carers in decisions about their health care is a key feature of health‐care practice. Professional health and social care students need to develop skills and attributes to best enable this to happen. Aims The aims were to explore service user and carer perceptions of behaviours, attributes and context required to enable shared decision making; to compare these perceptions to those of students and academic staff with a view to utilizing the findings to inform the development of student assessment tools. Methods A mixed methods approach was used including action learning groups (ALG) and an iterative process alongside a modified Delphi survey. Participants The ALGs were from an existing service user and carer network. The survey was sent to sixty students, sixty academics and 30 service users from 16 different professional disciplines, spanning four Universities in England. Results The collaborative enquiry process and survey identified general agreement that being open and honest, listening, showing respect, giving time and being up to date were important. The qualitative findings identified that individual interpretation was a key factor. An unexpected result was an insight into possible insecurities of students. Conclusions The findings indicate that distilling rich qualitative information into a format for student assessment tools could be problematic as the individual context could be lost, it is therefore proposed that the information could be better used as a learning rather than assessment tool. Several of those involved identified how they valued the process and found it beneficial. 相似文献
997.
Edson Eliah Susan Lewallen Khumbo Kalua Paul Courtright Michael Gichangi Ken Bassett 《Human resources for health》2014,12(Z1):S4
Background
This project examined the surgical productivity and attrition of non-physician cataract surgeons (NPCSs) in Tanzania, Malawi, and Kenya.Methods
Baseline (2008-9) data on training, support, and productivity (annual cataract surgery rate) were collected from officially trained NPCSs using mailed questionnaires followed by telephone interviews. Telephone interviews were used to collect follow-up data annually on productivity and semi-annually on attrition. A detailed telephone interview was conducted if a surgeon left his/her post. Data were entered into and analysed using STATA.Results
Among the 135 NPCSs, 129 were enrolled in the study (Kenya 88, Tanzania 38, and Malawi 3) mean age 42 years; average time since completing training 6.6 years. Employment was in District 44%, Regional 24% or mission/ private 32% hospitals. Small incision cataract surgery was practiced by 38% of the NPCSs. The mean cataract surgery rate was 188/year, median 76 (range 0-1700). For 39 (31%) NPCSs their surgical rate was more than 200/year. Approximately 22% in Kenya and 25% in Tanzania had years where the cataract surgical rate was zero. About 11% of the surgeons had no support staff.Factors significantly associated with increased productivity were: 1) located at a regional or private/mission hospital compared to a district hospital (OR = 8.26; 95 % CI 2.89 – 23.81); 2) 3 or more nurses in the eye unit (OR = 8.69; 95% CI 3.27-23.15); 3) 3 or more cataract surgical sets (OR = 3.26; 95% CI 1.48-7.16); 4) a separate eye theatre (OR = 5.41; 95% CI 2.15-13.65); 5) a surgical outreach program (OR = 4.44; 95% CI 1.88-10.52); and 6) providing transport for patients to hospital (OR = 6.39; 95% CI 2.62-15.59). The associations were similar for baseline and follow-up assessments. Attrition during the 3 years occurred in 13 surgeons (10.3%) and was due to retirement or promotion to administration.Conclusions
High quality training is necessary but not sufficient to result in cataract surgical activity that meets population needs and maintains surgical skill. Needed are supporting institutions and staff, functioning equipment and programs to recruit and transport patients.998.
Wendy R. Galpern Christopher S. Coffey Alberto Albanese Ken Cheung Cynthia L. Comella Dixie J. Ecklund Stanley Fahn Joseph Jankovic Karl Kieburtz Anthony E. Lang Michael P. McDermott Jeremy M. Shefner Jan K. Teller John L. P. Thompson Sharon D. Yeatts H. A. Jinnah 《Neurotherapeutics》2014,11(1):117-127
With advances in the understanding of the pathophysiology of dystonia, novel therapeutics are being developed. Such therapies will require clinical investigation ranging from exploratory studies to examine safety, tolerability, dosage selection, and preliminary efficacy to confirmatory studies to evaluate efficacy definitively. As dystonia is a rare and complex disorder with clinical and etiological heterogeneity, clinical trials will require careful consideration of the trial design, including enrollment criteria, concomitant medication use, and outcome measures. Given the complexities of designing and implementing efficient clinical trials, it is important for clinicians and statisticians to collaborate closely throughout the clinical development process and that each has a basic understanding of both the clinical and statistical issues that must be addressed. To facilitate designing appropriate clinical trials in this field, we review important general clinical trial and regulatory principles, and discuss the critical components of trials with an emphasis on considerations specific to dystonia. Additionally, we discuss designs used in early exploratory, late exploratory, and confirmatory phases, including adaptive designs. 相似文献
999.
R Hashimoto M Ikeda F Yamashita K Ohi H Yamamori Y Yasuda M Fujimoto M Fukunaga K Nemoto T Takahashi M Tochigi T Onitsuka H Yamasue K Matsuo T Iidaka N Iwata M Suzuki M Takeda K Kasai N Ozaki 《Translational psychiatry》2014,4(10):e472
The superior frontal gyrus (SFG), an area of the brain frequently found to have reduced gray matter in patients with schizophrenia, is involved in self-awareness and emotion, which are impaired in schizophrenia. However, no genome-wide association studies of SFG volume have investigated in patients with schizophrenia. To identify single-nucleotide polymorphisms (SNPs) associated with SFG volumes, we demonstrated a genome-wide association study (GWAS) of gray matter volumes in the right or left SFG of 158 patients with schizophrenia and 378 healthy subjects. We attempted to bioinformatically ascertain the potential effects of the top hit polymorphism on the expression levels of genes at the genome-wide region. We found associations between five variants on 1p36.12 and the right SFG volume at a widely used benchmark for genome-wide significance (P<5.0 × 10−8). The strongest association was observed at rs4654899, an intronic SNP in the eukaryotic translation initiation factor 4 gamma, 3 (EIF4G3) gene on 1p36.12 (P=7.5 × 10−9). No SNP with genome-wide significance was found in the volume of the left SFG (P>5.0 × 10−8); however, the rs4654899 polymorphism was identified as the locus with the second strongest association with the volume of the left SFG (P=1.5 × 10−6). In silico analyses revealed a proxy SNP of rs4654899 had effect on gene expression of two genes, HP1BP3 lying 3′ to EIF4G3 (P=7.8 × 10−6) and CAPN14 at 2p (P=6.3 × 10−6), which are expressed in moderate-to-high levels throughout the adult human SFG. These results contribute to understand genetic architecture of a brain structure possibly linked to the pathophysiology of schizophrenia. 相似文献
1000.