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31.
Human embryonic stem cells: research,ethics and policy 总被引:6,自引:0,他引:6
The use of human embryos for research on embryonic stem (ES) cells is currently high on the ethical and political agenda in many countries. Despite the potential benefit of using human ES cells in the treatment of disease, their use remains controversial because of their derivation from early embryos. Here, we address some of the ethical issues surrounding the use of human embryos and human ES cells in the context of state-of-the-art research on the development of stem cell based transplantation therapy. 相似文献
32.
TRIO amplification and abundant mRNA expression is associated with invasive tumor growth and rapid tumor cell proliferation in urinary bladder cancer 下载免费PDF全文
Zheng M Simon R Mirlacher M Maurer R Gasser T Forster T Diener PA Mihatsch MJ Sauter G Schraml P 《The American journal of pathology》2004,165(1):63-69
Studies by comparative genome hybridization have suggested that 5p amplification is related to tumor progression in urinary bladder cancer. In this study seven genes (TAS2R, ADCY2, DNAH5, CTNND2, TRIO, ANKH, and MYO10) located to 5p15.31-5p15.1 were analyzed by fluorescence in situ hybridization using a tissue microarray containing samples from tumors and cell lines with known 5p amplification by comparative genome hybridization. Amplification frequency was highest for TRIO, which maps to 5p15.2 and encodes a protein with a putative role in cell-cycle regulation. To further investigate the role of TRIO amplification in bladder cancer, a tissue microarray containing samples from 2317 bladder tumors was used for fluorescence in situ hybridization analysis. TRIO amplification was strongly associated with invasive tumor phenotype, high tumor grade, and rapid tumor cell proliferation (Ki67 LI) (P < 0.0001 each). Only 7 of 456 pTaG1/G2 tumors (1.5%) but 62 of 485 pT1-4 carcinomas (12.8%) had TRIO amplification. TRIO amplification was not associated with poor prognosis. Using a frozen bladder tumor tissue microarray RNA in situ hybridization confirmed that TRIO is up-regulated in amplified tumors. It is concluded that TRIO up-regulation through amplification has a potential role in bladder cancer progression. 相似文献
33.
The ultrasonic detection of insulinomas during surgical exploration of the pancreas 总被引:12,自引:0,他引:12
Licinio Angelini M.D. F.A.C.S. Mario Bezzi M.D. Gianfranco Tucci M.D. Marco M. Lirici M.D. Francesco Candiani M.D. Leopoldo Rubaltelli M.D. Carlo Tremolada M.D. Guido Tamburrano M.D. Gianfranco Fegiz M.D. F.A.C.S. 《World journal of surgery》1987,11(5):642-647
The sensitivity of preoperative imaging was evaluated for the localization of insulinomas in 2 series of 54 and 17 patients, respectively. In the first series, diagnosis was obtained with ultrasonography (US) in 14.8%, with computed tomographic (CT) scan in 60%, and with arteriography and/or angio CT scan in 75% of patients. In the second series, US, CT scan, and arteriography were performed preoperatively showing a sensitivity of 53% of one or more of the imaging techniques. The last 17 patients all underwent intraoperative pancreatosonography, and the insulinoma was localized in each.
Considering the high reliability of intraoperative ultrasonography, and the high costs and low benefits of other current diagnostic techniques, a new management plan is suggested for patients with a definite laboratory diagnosis of insulinoma.
Resumen La sensibilidad de la imagenología preoperatoria para la localización de insulinomas fue evaluada en 2 series de 54 y 17 pacientes respectivamente. En la primera serie, el diagnóstico fue logrado con ultrasonografía en 14.8%, con escanografía computadorizada en 60%, y con arteriografía y/o angiografía con escanografía computadorizada en 75% de los casos. En la segunda serie, la ultrasonografía, la escanografía computadorizada, y la arteriografía fueron realizadas preoperatoriamente demostrando una sensibilidad de 53% en una o más de las técnicas de imagenología. En los últimos 17 pacientes se realizó pancreatosonografía, la cual permitió la localización del tumor en 100% de los casos.En consideración a la elevada confiabilidad de la ultrasonografía intraoperatoria, y los altos costos y bajo rendimiento de las técnicas corrientes de diagnóstico, se sugiere un nuevo plan de manejo para pacientes con un diagnóstico de laboratorio certero de insulinoma. Se fundamenta en la localización ultrasonográfica intraoperatoria del tumor, la cual puede ser aplicada en los más comprensivos centras médicos.
Résumé La sensibilité de l'imagerie pré-opératoire permettant la localisation des insulinomes a été étudiée dans 2 séries de 54 et 17 sujects. Dans la première série le diagnostic fut posé par l'échographie dans 14.8% des cas, par la tomodensitométrie dans 60% des cas, par l'artériographie et/ou l'angiotomodensitométrie dans 75% des cas. Dans la seconde série, l'échographie, la tomodensitométrie et l'artériographie furent pratiquées avant l'intervention avec une sensibilité de 53% pour l'une ou pour plusieurs techniques. Chez les 17 derniers malades l'échographie opératoire fut systématiquement pratiquée et permit la localisation de la tumeur dans 100% des cas.Considérant la haute fiabilité de l'échographie opératoire, le coût élevé et les faibles résultats des autres techniques de diagnostic, un nouveau plan d'investigation est proposé pour explorer les malades qui présentèrent certains signes biologiques d'insulinome. Il repose sur la localisation per-opératoire de la tumeur par l'échographie, méthode qui peut être pratiquée dans des centres spécialisés.相似文献
34.
35.
G. Aumüller Paul-Martin Holterhus Lutz Konrad Burkhard von Rahden Olaf Hiort Murielle Esquenet Guido Verhoeven 《Anatomy and embryology》1998,197(3):199-208
As it is suggested that the androgen receptor mechanism is required for prostatic development, we attempted to determine
the appearance, expression and distribution of the androgen receptor in embryonic, infantile and pubertal human prostate.
Using mono- and polyclonal antibodies and a digoxigenin-labeled 713 bp riboprobe, the androgen receptor expression in paraffin
sections of fetal, infantile, and pubertal prostates was studied at the protein and RNA level. Under highly standardized conditions,
application of the polyclonal antibodies resulted in a weak cytoplasmic and nuclear labeling of the epithelium of fetal glands.
No immunoreaction was obtained with monoclonal antibodies. Applying the polyclonal antibody to pubertal and adult specimens,
immunoreactivity of the androgen receptor was positive in nuclei of adluminal and basal epithelial cells, in interstitial
and vascular smooth muscle cells and vascular endothelium, whereas ganglionic cells and enteroendocrine cells were negative.
In situ hybridization with the digoxigenin-labeled riboprobe gave clear positive results already in epithelium of very young
fetal specimens. A semiquantitative visual evaluation of in situ hybridizations showed that intermediate intensity of expression
was increased in pubertal and adult specimens, whereas strong expression was reduced in prostatic epithelium. Conclusions:
The essential findings are: (1) an early expression of androgen receptor mRNA in the fetal prostate; (2) no immunoreaction
of monoclonal antibodies against the androgen receptor in the same specimens, (3) a decrease of androgen receptor mRNA expression,
but increase in immunoreactivity of the androgen receptor protein with the onset of glandular maturation during puberty.
Accepted: 29 September 1997 相似文献
36.
Colleoni M Liessi G Mastrapasqua G Nelli P Vicario G Sgarbossa G Pancheri F Manente P 《Oncology reports》1996,3(5):879-882
Encouraging response rates and survival have been reported with intra-arterial (i.a.) chemotherapy and chemoembolization, but limited data are available on the association of the two treatment modalities. We therefore started a feasibility study of i.a. chemotherapy plus chemoembolization, performed every 28 days for 3 cycles, according to the following schedule: L-leucovorin (100 mg/m(2) i.v.), fluorouracil (800 mg/m(2) i.a.), and carboplatin (250 mg/m(2) i.a.). Chemoembolization with mitoxantrone (10 mg/m(2)) plus ethiodized oil was performed immediately after this treatment, followed by gelatin powder. Fourteen patients entered the study and were evaluable for side effects. Main patient characteristics were: males 13, females 1; median age 65 yr (range 45-75); stage TNM II-III 10, IVA 4; Childs' A 8, Childs' B 6; elevated baseline alpha-fetoprotein, 11; cirrhosis 14. No drug-related deaths have been observed. Ten patients were able to complete the program. The reasons for discontinuing treatment were worsening of liver functions in 3 cases and grade IV neutropenia in 1 patient. Eight patients had grade I-II pain and 10 patients had grade I-II fever. In conclusion the study demonstrated that chemoembolization plus i.a. chemotherapy is feasible in patients with hepatocellular carcinoma in cirrhosis and deserves further investigation. 相似文献
37.
Evaluation of vesico-urethral and sweating function in disorders presenting with parkinsonism 总被引:1,自引:0,他引:1
Milena De Marinis Guido Argenta Domenico Mele Antonio Carbone Giulio Baffigo Alessandro Agnoli 《Clinical autonomic research》1993,3(2):125-130
Investigation of vesico-urethral and sweating function was performed in twelve patients with classical idiopathic Parkinson's disease and ten patients with parkinsonism associated with features suggestive of more extensive involvement of the nervous system, as in the Shy—Drager syndrome. The urodynamic studies revealed detrusor hyperreflexia with reduction of maximal cystometric capacity in only one patient with Parkinson's disease (8%), but in nine patients with parkinsonism associated with other features (90%). Urethral sphincter electromyography did not indicate denervation in any patient of either group. Delayed or incomplete relaxation of the urethral sphincter during micturition was observed in seven patients with Parkinson's disease (58%) and in two patients of the other group (20%). Decreased sweating responses were found in both groups of patients when compared with control subjects. Hypohidrosis was more pronounced in parkinsonism associated with other features than in Parkinson's disease. Differences in sweating between the two sides of the body were observed in both groups of patients. Although there are differences in vesico-urethral and sweating function, they do not precisely differentiate between patients with classical Parkinson's disease and those with parkinsonism associated with features suggestive of more extensive involvement of the nervous system. 相似文献
38.
Prognostic impact of ANX7-GTPase in metastatic and HER2-negative breast cancer patients. 总被引:4,自引:0,他引:4
Meera Srivastava Lukas Bubendorf Mark Raffeld Christoph Bucher Jochen Torhorst Guido Sauter Cara Olsen Olli P Kallioniemi Ofer Eidelman Harvey B Pollard 《Clinical cancer research》2004,10(7):2344-2350
PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients. 相似文献
39.
Quantitative tumor apoptosis imaging using technetium-99m-HYNIC annexin V single photon emission computed tomography. 总被引:9,自引:0,他引:9
Christophe van de Wiele Christophe Lahorte Hubert Vermeersch D Loose Kris Mervillie Neil D Steinmetz Jean-Luc Vanderheyden Claude A Cuvelier Guido Slegers Rudi A Dierck 《Journal of clinical oncology》2003,21(18):3483-3487
PURPOSE: Radiolabeled annexin V may allow for repetitive and selective in vivo identification of apoptotic cell death without the need for invasive biopsy. This study reports on the relationship between quantitative technetium-99m- (99mTc-) 6-hydrazinonicotinic (HYNIC) radiolabeled annexin V tumor uptake, and the number of tumor apoptotic cells derived from histologic analysis. PATIENTS AND METHODS: Twenty patients (18 men, two women) suspected of primary (n = 19) or recurrent (n = 1) head and neck carcinoma were included. All patients underwent a spiral computed tomography (CT) scan, 99mTc-HYNIC annexin V tomography, and subsequent surgical resection of the suspected primary or recurrent tumor. Quantitative 99mTc-HYNIC annexin V uptake in tumor lesions divided by the tumor volume, derived from CT, was related to the number of apoptotic cells per tumor high-power field derived from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assays performed on sectioned tumor slices. RESULTS: Diagnosis was primary head and neck tumor in 18 patients, lymph node involvement of a cancer of unknown primary origin in one patient, and the absence of recurrence in one patient. Mean percentage absolute tumor uptake of the injected dose per cubic centimeter tumor volume derived from tomographic images was 0.0003% (standard deviation [SD], 0.0004%) at 1 hour postinjection (PI) and 0.0001% (SD, 0.0000%) at 5 to 6 hours PI (P =.012). Quantitative 99mTc-HYNIC annexin V tumor uptake correlated well with the number of apoptotic cells if only tumor samples with no or minimal amounts of necrosis were considered. CONCLUSION: In the absence of necrosis, absolute 99mTc-HYNIC annexin V tumor uptake values correlate well with the number of apoptotic cells derived from TUNEL assays. 相似文献