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Expression of cyclin D1, D3, E,and p27 in human renal cell carcinoma analysed by tissue microarray 总被引:6,自引:0,他引:6
Aberrations in the G1/S transition of the cell cycle have been observed in many malignancies and seem to be critical in the transformation process. Few studies have delineated the presence of G1/S regulatory defects and their clinical relevance in renal cell carcinoma (RCC). Therefore, we have examined the protein contents of cyclin D1, D3, E, and p27 in 218 RCCs, using tissue microarray and immunohistochemistry. The results from a subset of tumours were confirmed by Western blotting and immunohistochemical staining of regular tissue sections. Interestingly, low protein contents of cyclin D1 and p27 were associated with high nuclear grade, large tumour size, and poor prognosis for patients with conventional tumours. We further observed substantial differences in the pattern of G1/S regulatory defects between the different RCC subtypes. The majority of both conventional and papillary cases expressed p27; however, chromophobe tumours generally lacked p27 staining. In addition, conventional RCCs often expressed high cyclin D1 protein levels, while papillary RCCs exhibited high cyclin E. In summary, we have shown that G1/S regulatory defects are present in RCC and are associated with clinico-pathological parameters. The pattern of cell cycle regulatory defects also differed between RCC subtypes. 相似文献
94.
Rintala P Pukkala E Läärä E Vihko V 《International journal of cancer. Journal international du cancer》2003,107(2):268-270
The cohort consisted of 1,489 Finnish female physical education and 8,560 language teachers born after 1920 and alive in 1967. The 2 study populations were similar in social class and way of living and clearly discordant in physical activity both during their university studies and later in life. The incidence of breast cancer among these teachers up to the year 2000 was assessed through a record linkage with the Finnish Cancer Registry. The number of breast cancer cases among physical education teachers was 61 in 32,862 person-years and among language teachers was 404 in 177,188 person-years. In Poisson-regression analysis, the incidence rate ratio--adjusted for age, calendar time, number of children and age at first birth--for physical education vs. language teachers was overall 0.83 (95% confidence interval 0.63-1.09). This relative rate was 0.79 (0.46-1.36) in ages <50 years and 0.86 (0.62-1.18) in ages > or =50 years. Our study is concordant with the hypothesis that life-long physical activity may reduce the risk of breast cancer. 相似文献
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Hällsten K Yki-Järvinen H Peltoniemi P Oikonen V Takala T Kemppainen J Laine H Bergman J Bolli GB Knuuti J Nuutila P 《Obesity research》2003,11(2):257-265
OBJECTIVE: Insulin resistance in obese subjects results in the impaired use of glucose by insulin-sensitive tissues, e.g., skeletal muscle. In the present study, we determined whether insulin resistance in obesity is associated with an impaired ability of exercise to stimulate muscle blood flow, oxygen delivery, or glucose uptake. RESEARCH METHODS AND PROCEDURES: Nine obese (body mass index = 36 +/- 2 kg/m(2)) and 11 age-matched nonobese men (body mass index = 22 +/- 1 kg/m(2)) performed one-legged isometric exercise during hyperinsulinemia. Rates of femoral muscle blood flow, oxygen consumption, and glucose uptake were measured simultaneously in both legs using [(15)O]H(2)O, [(15)O]O(2), [(18)F]fluoro-deoxy-glucose, and positron emission tomography. RESULTS: The obese subjects exhibited resistance to insulin stimulation of glucose uptake in resting muscle, regardless of whether glucose uptake was expressed per kilogram of femoral muscle mass (p = 0.001) or per the total mass of quadriceps femoris muscle. At similar workloads, oxygen consumption, blood flow, and glucose uptake were lower in the obese than the nonobese subjects when expressed per kilogram of muscle, but similar when expressed per quadriceps femoris muscle mass. DISCUSSION: We conclude that obesity is characterized by insulin resistance of glucose uptake in resting skeletal muscle regardless of how glucose uptake is expressed. When compared with nonobese individuals at similar absolute workloads and under identical hyperinsulinemic conditions, the ability of exercise to increase muscle oxygen uptake, blood flow, and glucose uptake per muscle mass is blunted in obese insulin-resistant subjects. However, these defects are compensated for by an increase in muscle mass. 相似文献
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97.
Stage-specific vascular markers revealed by phage display in a mouse model of pancreatic islet tumorigenesis 总被引:9,自引:0,他引:9
The vasculature in the angiogenic stages of a mouse model of pancreatic islet carcinogenesis was profiled in vivo with phage libraries that display short peptides. We characterized seven peptides distinguished by their differential homing to angiogenic progenitors, solid tumors, or both. None homed appreciably to normal pancreatic islets or other organs. Five peptides selectively homed to neoplastic lesions in the pancreas and not to islet beta cell tumors growing subcutaneously, xenotransplant tumors from a human cancer cell line, or an endogenously arising squamous cell tumor of the skin. Three peptides with distinctive homing to angiogenic islets, tumors, or both colocalized with markers that identify endothelial cells or pericytes. One peptide is homologous with pro-PDGF-B, which is expressed in endothelial cells, while its receptor is expressed in pericytes. 相似文献
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99.
Eleven-year trends of stroke in Turku,Finland 总被引:1,自引:0,他引:1
Immonen-Räihä P Sarti C Tuomilehto J Torppa J Lehtonen A Sivenius J Mononen A Narva EV 《Neuroepidemiology》2003,22(3):196-203
The Turku Stroke Register included stroke events at all ages during the years 1982-1992. The incidence of stroke declined in all age groups, even in the oldest one. An even steeper decline was observed in mortality from stroke. Ischemic strokes contributed most to the observed decline, while subarachnoid and intracerebral hemorrhage showed mainly flat trends. Flat trends were also observed for recurrent strokes. The absolute number of strokes remained stable through the study years, but the population above 75 years of age doubled. More than half of the strokes occurred in people aged 75 years or older, and three fourths of them occurred in women. The incidence and mortality rate of ischemic stroke declined steeply in all age groups. Due to an increase in elderly people in the background population, the total number of strokes remained stable. Thus, in spite of the observed declining trends in incidence, the need for stroke care has not diminished. 相似文献
100.
OBJECTIVE: To assess the influence of central and peripheral neurological diseases on the incidence of accidental falls of the aged. DESIGN: 1. Case-control study with cross-section at two years and 2. prospective study in a follow-up up to seven years thereafter. SETTING: Sample of a population study including all 589 inhabitants older than 70 years in three rural communities. PARTICIPANTS: 44 subjects with recurrent falls during two years' follow-up and 41 age and sex matched controls. MEASURES: Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section. RESULTS: Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increases risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT. CONCLUSIONS: High incidence of falls was associated with chronic central nervous system diseases. Lumbar root lesions were more common among the fallers but did not increase the incidence of falls in the follow-up.Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section.Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increased risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity, and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT. 相似文献