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61.
P53 overexpression as an indicator of overall survival and response to treatment in osteosarcomas 总被引:5,自引:0,他引:5
Pápai Z Féja CN Hanna EN Sztán M Oláh E Szendrôi M 《Pathology oncology research : POR》1997,3(1):15-19
The p53 gene located at chromosome 17pl3 is found to be altered (allelic loss or other mutation) in multiple human cancers,
including osteosarcomas. The mutated gene produces a protein with a prolonged half-life thus rendering it detectable by conventional
immunohistochemistry. We examined the correlation between p53 expression and clinical prognosis as well as response to therapy.
Twentyone patients with previously untreated and histologically verified highly malignant osteosarcoma were used for this
study. Biopsy material taken both prior to the start of COSS 91 protocol and at the time of surgery (ten weeks later) was
examined for alterations in p53 protein expression and drug resistance. Two patients who had strong (+++) p53 protein expression
and three others who became positive during the chemotherapy had significantly worse prognosis (all of them died within one
year) than those who showed no p53 expression both at biopsy and after chemotherapy (all 11 patients are alive, average follow-up
time: 3.5 years). All patients who showed any kind of positive p53 protein expression on initial biopsy were non-respon-ders
to chemotherapy. In contrast, 69% (9 out of 13) of those who exhibited no p53 expression on initial biopsy were responders
or intermediate responders to chemotherapy. We concluded that p53 expression may be a useful prognostic factor in osteosarcomas.
The direct correlation between p53 positive expression and resistance to therapy can help in identifying patients who are
in need of a more vigorous or different chemotherapeutical protocol. 相似文献
62.
Cystic hypersecretory carcinoma (CHC) is a rare variant of intraductal carcinoma. A CHC in a 50-year-old woman was excised and processed for light and electron microscopy and immunohistochemistry. The tumor had a marked cystic appearance. The walls of the cysts consisted of epithelial and myoepithelial cells and a well-developed basement membrane. The epithelial cells contained well-developed rough-surfaced endoplasmatic reticulum and Golgi apparatus. Secretory granules were not detected, with the exception of a few mucus-producing cells. The secretion was predominantly homogenous, reminiscent of thyroid colloid, and demonstrated distinct PAS positivity. The cells displayed a strong labeling with epithelial membrane antigen (EMA) and EMA-positive structures were observed within the intraluminal secretion, too. Some of these were stained by alcian blue. In addition, the colloid-like material was admixed with mucus showing a filamentous internal structure and lipid droplets resulting in some heterogenity of the secretion. Intraductal micropapillary proliferation in some of the cysts and adjacent nondistended ducts was a further defining feature of the tumor. Steroid hormone receptor and Ki-67 proliferation marker immuno his Tochemistry showed scattered positivity among the tumor cells. These results are in agreement with previous observations and further clarify the nature of this low-grade in situ cancer. 相似文献
63.
Bone Mineral Density and Androgen Levels in Elderly Males 总被引:4,自引:0,他引:4
Rapado A Hawkins F Sobrinho L Díaz-Curiel M Galvao-Telles A Arver S Melo Gomes J Mazer N Garcia e Costa J Horcajada C López-Gavilanes E Mascarenhas M Papapietro K López Alvarez MB Pereira MC Martinez G Valverde I García JJ Carballal JJ García I 《Calcified tissue international》1999,65(6):417-421
To clarify the relationship of sex male hormones and bone in men, we studied in 140 healthy elderly men (aged 55–90 years)
the relation between serum levels of androgens and related sex hormones, bone mineral density (BMD) at different sites, and
other parameters related to bone metabolism. Our results show a slight decrease of serum-free testosterone with age, with
an increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a third of the elderly subjects studied.
BMD decreased significantly with age in all regions studied, except in the lumbar spine. We found a positive correlation between
body mass index (BMI) and BMD at the lumbar spine and femoral neck (P < 0.001). No relationship was found (uni- and multivariate regression analysis) between serum androgens or sex hormone-binding
globulin (SHBG) and BMD. We found a positive correlation of vitamin D binding protein (DBP) and osteocalcin with lumbar spine
BMD and with BMI, DBP, IGF-1, and PTH with femoral neck BMD. In conclusion, there is a slight decline in free testosterone
and BMD in the healthy elderly males. However, sex male hormones are not correlated to the decrease in hip BMD. Other age-related
factors must be associated with bone loss in elderly males.
Received: 29 April 1997 / Accepted: 9 November 1997 相似文献
64.
José R. Pallás Concepción Fariñas-Álvarez Dolores Prieto Miguel Delgado-Rodríguez 《European journal of epidemiology》1999,15(8):699-704
In order to know the prevalence and risk factors for coinfections by human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) among injecting drug users (IDUs), a cross-sectional study was carried out in two prisons of the province of Cantabria, northern Spain. Three hundred and sixty-two IDU inmates were recruited. All inmates were interviewed and their blood tested for HIV, HBV and HCV. Crude and multiple risk factor adjusted for (by polychotomous logistic regression) odds ratios were calculated. Prevalence of HBV-HCV coinfection (42.5%) was higher than HIV-HBV-HCV coinfection (37.3%), whereas monoinfections were very uncommon (overall: 13%). Long-term injectors and reincarceration were the foremost risk factors for both coinfections, showing a trend between the degree of association and the number of viruses infecting a patient. No significant relationship between coinfection status and sexual practices was observed. The results related to coinfections are consistent with previous studies of prevalence and risk factors for HIV, HBV and HCV, in indicating that the high rates of coinfections among IDU inmates emphasise the need to harm-reduction policy across prisons in Spain. 相似文献
65.
Bánkfalvi Á Piffkó J Öfner D Dreier R Böcker W Werner K 《Pathology oncology research : POR》1996,2(1-2):71-77
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic
digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in
immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating
methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the
microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity
in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced
in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2
antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully
for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory
molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar
organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized
AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric
study group as the standardized method for AgNOR analysis in archival material. 相似文献
66.
Lipoma of the uterus is a rare condition usually developing in postmenopausal women. Clinical symptoms and physical signs are similar to those found in leiomyomas. The histiogenesis of these lesions is still unclear. We report a case of a pure intramural lipoma of the uterus illustrating characteristic morphological and histological findings. Additional immunohistochemical studies underline the lipomatous but not leiomyomatous nature of the tumor. 相似文献
67.
Summary We report 137 recurrent supratentorial astrocytomas. The primary tumours diagnosed on the basis of a grading system with three stages were 72 astrocytomas I and 65 astrocytomas II. In the first group 14% of the recurrences were not changed, 55.5% became astrocytomas II, and 30.5% became glioblastomas. In the second group 55.4% were unchanged, and 44.6% became glioblastomas. The postoperative intervals until reintervention or death were statistically examined. It seems that the recurrence time chiefly depends on the nature of the primary tumour. The transformation of an astrocytoma I to a glioblastoma takes longer than the transformation of an astrocytoma II into a glioblastoma. In about two thirds of all astrocytomas an increase of malignancy is to be expected. From the histological picture it is not possible in an individual case to predict the likelihood or speed of malignant change. With regard to the effect of irradiation the authors conclude that radiotherapy most probably does not produce malignancy.The authors wish to express their gratitude to the founder and organizer of the Institute of Neurosurgery in Budapest, Prof. Dr. L. Zoltán (), for his promotion of these investigations. 相似文献
68.
Pseudomixoma peritoneal tipo adenomucinosis peritoneal diseminada con imágenes radiológicas atípicas
Manuel Vallalta Morales Ángel Segura Huerta Carmen Gil Adiego Laura Palomar Abad Jorge Molina Saera Roberto Díaz Beveridge 《Clinical & translational oncology》2004,6(3):173-175
Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management. 相似文献
69.
Juan José Criado-Álvarez M. Consuelo Morant Ginestar Rocío García-Pina Antonio de Lucas Veguillas 《Clinical & translational oncology》2003,5(1):27-32
Background. To know the temporary tendency in the mortality due to breast cancer in Castilla-La Mancha (CLM, Spain) between 1975 and 1998. Patients and methods. The mortality data are from the Registry of Mortality of CLM. Crude and standardized mortality rates are calculated. In order to evaluate the tendency, we use the Poisson’s log- linear model. We have calculated the accumulated rate to die and the accumulated risks to die and to become ill. Results. Between 1975 and 1998, 2.44% of all deaths in CLM women were consequence of a breast cancer. The crude rate increased from the 14.55 by 100,000 in 1975 to 25.23 by 100,000 in 1998, with an annual average increase of 1.49%. The average age of death increased until the 67 years old in 1998 as opposed to the 59 years old of 1975. The risk of dying of a breast cancer increased in the period from 1.4% in 1975 to 2.34% in 1998. Conclusion. Mortality by breast cancer has raised until 1993, when it begun to decrease. In general, women with breast cancer die elderly, and young women have increased risk to fall ill. 相似文献