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51.
Merkel cell carcinoma is an uncommon and aggressive primary cutaneous neuroendocrine carcinoma with a high rate of recurrence and metastasis. Optimal management is controversial; consequently, it is imperative to identify the signaling pathways involved in the pathogenesis of Merkel cell carcinoma so that effective therapeutic targeting agents can be developed. We previously reported that K homology domain-containing protein overexpressed in cancer is expressed in high-grade neuroendocrine carcinomas of the lung and extrapulmonary small cell carcinomas. The K homology domain-containing protein overexpressed in cancer (KOC), also known as L523S and IMP-3, is an insulin-like growth factor II messenger RNA-binding protein that promotes tumor cell proliferation by enhancing insulin-like growth factor II protein expression. Expression of KOC in Merkel cell carcinoma has not been investigated. We studied 20 Merkel cell carcinomas by immunohistochemistry using a monoclonal antibody against L523S/KOC. Of 20 Merkel cell carcinomas, 18 (90%) overexpressed KOC, with 11 (55%) overexpressing KOC in greater than 90% of tumor cells, 3 (15%) overexpressing KOC in 50% to 90% of tumor cells, 3 (15%) overexpressing KOC in 10% to 50% of tumor cells, and 1 (5%) overexpressing KOC in less than 10% of tumor cells. The immunostaining intensity was variable, with moderate to strong staining in 14 cases and weak staining in the remaining 4. Extent of expression of K homology domain-containing protein overexpressed in cancer predicted metastasis (P = .04) and was weakly correlated with increased tumor size (P = .08). In conclusion, Merkel cell carcinoma expresses K homology domain-containing protein overexpressed in cancer with an expression pattern similar to high-grade neuroendocrine carcinomas of the lung and extrapulmonary small cell carcinomas. We propose K homology domain-containing protein overexpressed in cancer as a potential target molecule for the treatment of high-grade neuroendocrine carcinomas, irrespective of anatomical location, and a potential marker to predict metastatic disease. 相似文献
52.
Simon RA di Sant'Agnese PA Huang LS Xu H Yao JL Yang Q Liang S Liu J Yu R Cheng L Oh WK Palapattu GS Wei J Huang J 《Human pathology》2009,40(2):252-258
Small cell neuroendocrine carcinoma of the prostate is a rare variant of prostatic cancer that shares morphologic similarity with prostatic adenocarcinoma of Gleason 5 pattern. It has also been considered morphologically and immunohistochemically indistinguishable from small cell neuroendocrine carcinomas of other origins. CD44 is a cell-surface molecule proposed to identify cancer stem/progenitor cells in prostate cancer. We performed immunohistochemical study for CD44 expression in 11 cases of prostatic small cell neuroendocrine carcinoma and compared its patterns of expression with 73 cases of prostatic adenocarcinoma and 47 cases of small cell neuroendocrine carcinomas of other organs. Strong and diffuse membrane staining for CD44 was observed in 100% of the prostatic small cell neuroendocrine carcinomas. In conventional adenocarcinomas of the prostate, positive staining was only seen in rare, scattered tumor cells; and CD44 staining was negative in most of the small cell neuroendocrine carcinomas of nonprostate origin. The difference in CD44 expression between small cell neuroendocrine carcinomas of the prostate and those of other organs are statistically significant (P < .001). Our study demonstrates the utility of immunohistochemical staining for CD44 in distinguishing prostatic small cell neuroendocrine carcinoma from its mimickers including prostatic adenocarcinoma of Gleason 5 pattern and small cell neuroendocrine carcinomas of other organs. CD44 is the first marker that shows a high degree of tissue/organ specificity for small cell neuroendocrine carcinomas. Because CD44 is a putative marker of prostate cancer stem cells, the strong and diffuse expression of CD44 and the lack of expression of prostate luminal differentiation markers androgen receptor and prostatic specific antigen in prostatic small cell neuroendocrine carcinomas suggest that the tumor cells may retain cancer stem cell features. 相似文献
53.
The climbing fibre projection from the motor cortex to the cerebellar cortical C1 zone in the posterior lobe of the rat cerebellum was investigated using a combination of physiological, anatomical and neuropharmacological techniques. Electrical stimulation of the ipsilateral fore- or hindimbs or somatotopically corresponding parts of the contralateral motor cortex evoked climbing fibre field potentials at the same cerebellar recording sites. Forelimb-related responses were located in the C1 zone in the paramedian lobule or lobulus simplex and hindlimb-related responses were located in the C1 zone in the copula pyramidis. Microinjections of anterograde axonal tracer (Fluoro-Ruby or Fluoro-Emerald) were made into the fore- or hindlimb parts of the motor cortex where stimulation evoked the largest cerebellar responses. After a survival period of 7–10 days, the neuraxis was examined for anterograde labelling. No terminal labelling was ever found in the inferior olive, but labelled terminals were consistently found in a well-localized site in the dorso-medial medulla, ventral to the gracile nucleus, termed the matrix region. Pharmacological inactivation of the matrix region (2 mm caudal to the obex) selectively reduced transmission in descending (cerebro-olivocerebellar) but not ascending (spino-olivocerebellar) paths targeting fore- or hindlimb-receiving parts of the C1 zone. Transmission in spino-olivocerebellar paths was either unaffected, or in some cases increased. The identification of a novel pre-olivary relay in cerebro-olivocerebellar paths originating from fore- and hindlimb motor cortex has implications for the regulation of transmission in climbing fibre pathways during voluntary movements and motor learning. 相似文献
54.
Moallem HJ Taningo G Jiang CK Hirschhorn R Fikrig S 《Clinical immunology (Orlando, Fla.)》2002,105(1):75-80
Purine nucleoside phosphorylase (PNP) deficiency results in an autosomal recessive immunodeficiency disease characterized by initial involvement of cellular immunity and neurological manifestations with subsequent abnormalities of humoral immunity. The initial presentation and clinical course has varied widely in the relatively few published cases. The molecular basis has been reported in only 10 patients, precluding evaluation of phenotype-genotype relationships. We now report clinical, immunologic, and molecular findings in a new case of relatively early onset that emphasizes hypotonia and developmental delay as early manifestations. The patient carried two novel missense mutations (Gly56A1a and Val217Ile) on the same allele in apparent homozygosity. Expression of each of the mutant enzymes in vitro demonstrated that the Gly156A1a mutation abolished enzyme activity while the Val217Ile mutation was without obvious effect and is therefore a normal variant. Such "normal" polymorphisms might be associated with a variable response to the immunosuppressive PNP inhibitors currently in clinical trials. 相似文献
55.
The first checkpoint in T cell development, beta selection, has remained incompletely characterized for lack of specific surface markers. We show that CD27 is upregulated in DN3 thymocytes initiating beta selection, concomitant with intracellular TCR-beta expression. Clonal analysis determined that CD27high DN3 cells generate CD4+CD8+ progeny with more than 90% efficiency, faster and more efficiently than the CD27low majority. CD27 upregulation also occurs in gammadelta-selected DN3 thymocytes in TCR-beta-/- mice and in IL2-GFP transgenic reporter mice where GFP marks the earliest emerging TCR-gammadelta cells from DN3 thymocytes. With CD27 to distinguish pre- and postselection DN3 cells, a detailed gene expression analysis defined regulatory changes associated with checkpoint arrest, with beta selection, and with gammadelta selection. gammadelta selection induces higher CD5, Egr, and Runx3 expression as compared to beta selection, but it triggers less proliferation. Our results also reveal differences in Notch/Delta dependence at the earliest stages of divergence between developing alphabeta and gammadelta T-lineage cells. 相似文献
56.
This study sought to identify the future directions in three domains: clinical practice, research, and training of clinical child and adolescent psychologists in the upcoming decade. Doctoral‐level active members in the field were surveyed via a two‐round Delphi survey (45 in round 1; 35 in round 2). Evidence‐based practice received the greatest consensus by the participants and highest rank in each of the three domains. Other highly ranked clinical practice directions included prevention and early diagnosis and treatment, and clinical services for specific psychological problems. Research directions focused on biological and social factors interactions in the etiology and treatment and specific child and adolescent disorders. In the training domain, major directions included the pursuit of specialty training in child and adolescent psychology and training emphasizing the biological basis of behavior. Implications of these future directions are discussed. © 2009 Wiley Periodicals, Inc. J Clin Psychol 65: 1–12, 2009. 相似文献
57.
Rochelle W Tyl Christina B Myers Melissa C Marr Carol S Sloan Nora P Castillo M Michael Veselica John C Seely Stephen S Dimond John P Van Miller Ronald S Shiotsuka Gisela D Stropp John M Waechter Steven G Hentges 《Toxicological sciences》2008,102(2):392-412
No information exists on reproductive/developmental effects in mice exposed to dietary 17beta-estradiol (E2) over multiple generations. Therefore, under OECD Test Guideline 416 with enhancements, CD-1 mice (F0 generation, 25 mice/sex/group) were exposed to dietary E2 at 0, 0.001, 0.005, 0.05, 0.15, or 0.5 ppm ( approximately 0, 0.2, 1, 10, 30, or 100 mug E2/kg body weight/day) for 8 weeks prebreed, 2 weeks mating, approximately 3 weeks gestation, and 3 weeks lactation. At weaning, selected F1 offspring (F1 parents; 25/sex/group) and extra retained F1 males (one per litter) were exposed to the same dietary concentrations and durations as the F0 generation; study termination occurred at F2 weaning; F1/F2 weanlings (up to three per sex per litter) were necropsied with organs weighed. At 0.5 ppm, effects were increased F1/F2 perinatal loss, prolonged F0/F1 gestational length, reduced numbers of F2 (but not F1) litters/group, reduced F1/F2 litter sizes, accelerated vaginal patency (VP) and delayed preputial separation (PPS), increased uterus + cervix + vagina weights (UCVW) in F0/F1 adults and F1/F2 weanlings, and decreased testes and epididymides weights (TEW) in F1/F2 weanlings. At 0.15 ppm, effects were increased UCVW in F0/F1 adults and F1/F2 weanlings, accelerated VP, delayed PPS, and reduced TEW in F1/F2 weanlings. At 0.05 ppm, UCVW were increased in F1/F2 weanlings, and PPS was delayed only in extra retained F1 males. There were no biologically significant or treatment-related effects on F0/F1 parental body weights, feed consumption, or clinical observations, or on F0/F1 estrous cyclicity, F0/F1 andrology, or F1/F2 anogenital distance at any dose. The no observable effect level was 0.005 ppm E2 ( approximately 1 mug/kg/day). Therefore, the mouse model is sensitive to E2 by oral administration, with effects on reproductive development at doses of 10- 100 mug/kg/day. 相似文献
58.
Maselli RA Dunne V Pascual-Pascual SI Bowe C Agius M Frank R Wollmann RL 《Muscle & nerve》2003,28(3):293-301
Rapsyn, a 43-kDa postsynaptic protein, is essential for anchoring and clustering acetylcholine receptors (AChRs) at the endplate (EP). Mutations in the rapsyn gene have been found to cause a postsynaptic congenital myasthenic syndrome (CMS). We detected six patients with CMS due to mutations in the rapsyn gene (RAPSN). In vitro studies performed in the anconeus muscle biopsies of four patients showed severe reduction of miniature EP potential amplitudes. Electron microscopy revealed various degrees of impaired development of postsynaptic membrane folds. All patients carried the N88K mutation. Three patients were homozygous for N88K and had less severe phenotypes and milder histopathologic abnormalities than the three patients who were heterozygous and carried a second mutation (either L14P, 46insC, or Y269X). Surprisingly, two N88K homozygous patients had one asymptomatic relative each who carried the same genotype, suggesting that additional genetic factors to RAPSN mutations are required for disease expression. 相似文献
59.
Tractenberg RE Weiner MF Thal LJ 《The Journal of neuropsychiatry and clinical neurosciences》2002,14(1):11-18
To estimate the prevalence of, and develop norms for, significant agitation in community-dwelling persons with Alzheimer's disease (AD), the authors applied three different criteria to persons with AD (n=235) and normal elderly control subjects (NEC; n=64). The criteria were used to identify the minimum total score on the Cohen-Mansfield Agitation Inventory (CMAI) that represents significant or "excessive" agitation and to estimate its prevalence. The "ultraliberal" criterion resulted in 99.1% of persons with AD and 56.6% of NEC being classified as "excessively" disturbed. The "liberal" and "conservative" criteria classified 66.7% and 68.2% of persons with AD, and no NEC, as "excessively" disturbed. The authors conclude that the best estimate of prevalence of excessive agitation in this population is 67.5%, and that individuals with CMAI scores of 0 to 14 probably should not be considered to have excessive agitation. 相似文献
60.
Travis LB Gospodarowicz M Curtis RE Clarke EA Andersson M Glimelius B Joensuu T Lynch CF van Leeuwen FE Holowaty E Storm H Glimelius I Pukkala E Stovall M Fraumeni JF Boice JD Gilbert E 《Journal of the National Cancer Institute》2002,94(3):182-192
BACKGROUND: Lung cancer is a frequent cause of death in patients cured of Hodgkin's disease, but the contributions of chemotherapy, radiotherapy, and smoking are not well described. We quantified the risk of treatment-associated lung cancer, taking into account tobacco use. METHODS: Within a population-based cohort of 19 046 Hodgkin's disease patients (diagnosed from 1965 through 1994), a case-control study of lung cancer was conducted. The cumulative amount of cytotoxic drugs, the radiation dose to the specific location in the lung where cancer developed, and tobacco use were compared for 222 patients who developed lung cancer and for 444 matched control patients. All statistical tests were two-sided. RESULTS: Treatment with alkylating agents without radiotherapy was associated with increased lung cancer risk (relative risk [RR] = 4.2; 95% confidence interval [CI] = 2.1 to 8.8), as was radiation dose of 5 Gy or more without alkylating agents (RR = 5.9; 95% CI = 2.7 to 13.5). Risk increased with both increasing number of cycles of alkylating agents and increasing radiation dose (P for trend <.001). Among patients treated with mechlorethamine, vincristine, procarbazine, and prednisone (MOPP), risk increased with cumulative amounts of mechlorethamine and procarbazine (P<.001) when evaluated separately. Statistically significantly elevated risks of lung cancer were apparent within 1-4 years after treatment with alkylating agents, whereas excess risk after radiotherapy began 5 years after treatment and persisted for more than 20 years. Risk after treatment with alkylating agents and radiotherapy together was as expected if individual excess risks were summed. Tobacco use increased lung cancer risk more than 20-fold; risks from smoking appeared to multiply risks from treatment. CONCLUSIONS: Past treatments with alkylating agents and radiation therapy for Hodgkin's disease were associated with an increased risk of lung cancer in a dose-dependent and additive fashion. The precise risk estimates, however, should be interpreted cautiously, given the possible residual and enhancing effects of tobacco. 相似文献