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Primary cell cultures of two human pheochromocytomas (PC) that were associated with high serum levels of adrenaline and noradrenaline were developed to study the effects of nerve growth factor (NGF) and dexamethasone on the morphology and function of PC cells in vitro. By phase-contrast microscopy, cultured cells were small and hyperchromatic on the first day of culture; neurite-like processes that extended to other cells developed several days later and were maintained for more than 3 months. NGF (100ng/ml), dexamethasone (10–5M), or NGF + dexamethasone were added to the culture media 2 weeks after the cultured cells had stabilized. Catecholamine concentrations in the medium were maintained at higher levels after addition of NGF, dexamethasone, or NGF + dexamethasone as compared to control cells. In the presence of NGF, extension of neurite-like processes was clearly accelerated, while high levels of dexamethasone inhibited growth of processes. These in vitro studies showed that the addition of NGF or the removal of dexamethasone induces differentiation of adrenal neurons present in pheochromocytomas, suggesting that adrenocortical steroid hormones influence the morphological control of adrenal medullary cells.  相似文献   
2.
Ultrastructure of human pheochromocytoma cells cultured for long periods   总被引:1,自引:0,他引:1  
We conducted ultrastructural analysis of human pheochromocytoma (PC) cells maintained in primary culture for about 10 months. The cells were first isolated by the enzymatic treatment of a surgically resected tissue specimen obtained from a 37-year-old man with PC, a condition which is characterized by elevated blood levels of adrenaline and noradrenaline. It was found that noradrenaline production in the medium continued until the 90th day of culture (1330 pg/ml). The production level decreased to 20 pg/ml on the 180th day, and to 18 pg/ml on the 300th day. Examination under a transmission electron microscope (TEM) at 4 weeks of culture revealed electron-dense granules (about 200 nm in size and, presumably, rich in catecholamines), which were also observed in the tumor cells from the original PC tissue. Neurite-like processes grew at around 1 week of culture, and were still maintained at 6 months of culture. But, after 6 months of culture, the neurite-like processes contained a rosary-like elevated structure, which was suggestive of cell degeneration, as determined by a plasma polymerization replica method and observed with a scanning electron microscope. When cells were examined under the TEM, fewer electron-dense granules were observed in the cell bodies, with more numerous lipofuscin-like granules and filaments. Thus, electron-dense granules, which, presumably, contain catecholamines, were seen in a long-term culture of human PC cells. These granules decreased in number in parallel with the decrease in catecholamine levels in the culture.  相似文献   
3.
The diagnostic potential of a new bone resorption marker, type I collagen-cross-linked N telopeptide (NTx), for bone metastasis of prostate cancer was evaluated. Ninty-one prostate cancer patients underwent bone scintigraphy, and urine NTx/creatinine (NTx/Cr) was measured. Urine NTx/Cr levels were compared with bone scintigraphic results. Urine NTx/Cr levels in the bone metastasis-positive group (n = 47) were 92.9 +/- 105.1 nmol/L of bone collagen, which is equivalent to per millimole of urinary creatinine (nmol/L BCE/mmol/L Cr), significantly higher than the level of the bone metastasis-negative group (n = 44) (59.0 +/- 41.6 nmol/L BCE/mmol/L Cr). When patients were classified by the extent of disease grade (EOD grade) nomenclature, the urine NTx/Cr level of the EOD (4+) group was 209.5 +/- 186.5 nmol/L BCE/mmol/L Cr. This level was significantly higher than those of the EOD (-) group (59.0 +/- 41.6 nmol/L BCE/mmol/L Cr), EOD (1+) group (59.0 +/- 47.8 nmol/L BCE/mmol/L Cr), and EOD (2+) group (81.1 +/- 41.3 nmol/L BCE/mmol/L Cr). However, no significant difference was observed between the EOD (-) and EOD (1+) groups. The mean change in urine NTx/Cr level 3 to 17 months after the first bone scintigraphy and urine NTx/Cr examination in the bone metastasis-progression group (n = 8) was 11.0 +/- 31.2 nmol/L BCE/mmol/L Cr, significantly higher than that in the bone metastasis-regression group (n = 15) (-26.8 +/- 40.7 nmol/L BCE/mmol/L Cr). In conclusion, urine NTx /Cr can be measured noninvasively and reflects the state of bone metastasis. However, the sensitivity of urine NTx/Cr is not as high as that of bone scintigraphy. Therefore, it may provide an auxiliary diagnostic index for bone scintigraphy.  相似文献   
4.
The intra- and inter-nephron heterogeneity of renal gluconeogenesis within rat proximal tubules and the effects of chronic metabolic acidosis and chronic potassium(K)-depletion were studied using isolated proximal tubules of rats by directly measuring glucose synthesized.The gluconeogenic activity from pyruvate and glutamine in control rats was almost limited to within the early proximal tubule (S1: 45.4±5.7 pmol/mm/60 min from pyruvate; 58.0±6.0 from glutamine). Very low, but detectable gluconeogenesis was observed in the middle portion of the proximal tubule (S2:9.9±2.2 from pyruvate; 4.8±1.1 from glutamine). The rate of glucose production in the terminal proximal tubule (S3) was negligible. Furthermore, gluconeogenesis from glutamine of superficial (SF) nephrons was significantly higher than that of juxtamedullary (JM) ones, whereas no difference was seen in gluconeogenesis from pyruvate.In acidotic and K-depleted rats, significant increase could be seen in S1 and S2, but the increase in S3 was not significant. By the serial determination in acidosis, the glucose production from both substrates was found to be the highest at the second 1 mm segment from the glomerulus, and it decreased downward along the proximal tubule. In acidosis, glucose production from both substrates in SF nephrons and that from glutamine in JM ones were elevated significantly compared with the control, but that from pyruvate in JM nephrons did not change.These results suggest that S1 of the SF nephron plays the most important role in gluconeogenesis in the control, whereas S1 of the JM nephron and S2 contribute to gluconeogenesis in acidotic and/or possibly K-depleted rats.  相似文献   
5.
Summary VAU therapy (vinblastine, Adriamycin, and UFT) was given postoperatively to 31 patients with stage I, II, or III renal-cell carcinoma, and the incidence of relapse as well as the survival of patients were studied. Administration was started at 7–14 days post-surgery; 5 mg/m2 vinblastine and 30 mg/m2 Adriamycin were given i.v. once every 4 weeks for a total of five courses, and three capsules of UFT (containing 300 mg tegafur) were given p.o. every day for 2–3 years. The postoperative observation period ranged from 2 years and 6 months to 7 years and 1 month (mean, 4 years and 2 months). The 1-year survival of patients was 100%, and the 3- and 5-year survival values were 96%. These results were significantly better (P<0.01) than the respective values (81%, 72%, and 60%) obtained for the historical controls, i.e., the 60 patients with stage I, II, or III renal-cell carcinoma who received no chemotherapy. Side effects such as alopecia, gastrointestinal symptoms, and myelosuppression were encountered, but all symptoms were so mild and transient that discontinuation of the treatment was not necessary. As VAU therapy might be useful as adjuvant chemotherapy for renal-cell carcinoma, it seems to merit further study.  相似文献   
6.
We compared the ability to diagnose skeletal metastasis between serum prostate specific antigen (PSA), C-terminal propeptide of blood type I procollagen (PICP), and urine type I collagen-crosslinked N telopeptide (NTx) in prostate cancer patients. In sixty-nine patients with prostate cancer, bone scintigraphy was performed, and serum PSA and PICP and urine NTx were measured. The median level of serum PSA in the osseous metastasis-negative group (n = 33) was 0.80 ng/ml being significantly lower as compared to the osseous metastasis-positive group (n = 36, 7.70 ng/ml) (p < 0.0001). The serum PICP and urine NTx/Cr levels appeared lower in the osseous metastasis-negative group than the osseous metastasis-positive group, but there was no significant difference. Logistic regression analysis showed that ability to diagnose skeletal metastasis of serum PSA was 68.1% and superior to those of serum PICP (56.5%) and urine NTx/Cr (53.6%). Serum PSA improved the ability to diagnose skeletal metastasis when combined with serum PICP or urine NTx/Cr. When patients were grouped according to the extent of disease grade (EOD grade) nomenclature, Spearman's correlation coefficient by rank showed that serum PSA was most significantly correlated with EOD grade (p < 0.0001). In 14 patients whose skeletal metastases progressed or regressed, the change of serum PSA more clearly separated the osseous metastasis-regression group and osseous metastasis-progression group than did serum PICP and urine NTx/Cr. Serum PSA was more reliable than bone resorption and formation markers produced by crosslinking of type I collagen.  相似文献   
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