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1.
The relationship between the nuclear DNA histogram pattern of tumor cells obtained by bronchoscopic brushing and the response to combination chemotherapy (Cytoxan + Adriamycin + Vincristine) was studied in 28 patients with small-cell carcinoma of the lung. Microspectrophotometric analysis of the tumor cells showed a near-diploid nuclear DNA pattern in 18 patients and a hyperdiploid pattern in 10 patients. Eight of the ten patients with the hyperdiploid pattern showed a good response (complete or partial response) to the chemotherapy. However, of the 18 patients with the near-diploid DNA pattern, only 2 displayed a good response; the remaining 16 patients exhibited no response. The hyperdiploid DNA pattern of tumor cells was thus associated with a better response to chemotherapy than was the near-diploid pattern. These results indicate that the nuclear DNA histogram pattern may be an indicator for predicting the degree of response to chemotherapy in small-cell carcinoma of the lung.  相似文献   
2.
Thyrotropin-releasing hormone (TRH) and insulin were measured by radioimmunoassay in acetic-acid extracts of 19 pancreatic islet cell tumors induced by streptozotocin and nicotinamide in rats. In addition, gel filtration properties of TRH-immunoreactivity and immunoreactive insulin (IRI) were examined in 5 and 14 tumors, respectively. TRH was demonstrated in 10 of 19 tumors, with a mean of 166 +/- 47 (SEM) pg/mg wet weight, whereas the concentration was less than 3 pg/mg wet weight in the other tumors. In contrast, all tumors contained IRI, with a mean of 11.0 +/- 1.6 micrograms/mg wet weight. Ten tumors in which TRH was demonstrated contained more IRI than those in which TRH was not detected (13.1 +/- 1.8 vs 6.5 +/- 1.7 micrograms/mg wet weight, P less than 0.02). After gel filtration, all TRH immunoreactivity was eluted at the same place as synthetic TRH in the 5 tumors. In addition, gel filtration elutes showed essentially the same pattern of IRI in the 14 tumors, with 3 peaks. The predominant IRI peak comigrated with marker insulin (95.7 +/- 0.8%), another prominent peak occurred coincident with proinsulin standard (3.3 +/- 0.5%), a third peak was present in the void volume (0.28 +/- 0.04%). These distributions of IRI were similar to those in extracts of normal pancreases. The present studies demonstrate TRH immunoreactivity in pancreatic islet cell tumors induced by streptozotocin and nicotinamide in rats. Chemically induced insulinomas can serve as a model for insulin storage which is analogous to islet B cells.  相似文献   
3.
Establishment of five human myeloma cell lines   总被引:3,自引:0,他引:3  
Summary Five human myeloma cell lines, KMM-1, KMS-5, KMS-11, KMS-12- PE, and KMS-12-BM, have been established at Kawasaki Medical School since 1980. As the KMS-12-PE and KMS-12-BM lines were obtained from the same patient, these five cell lines have been derived from four patients with multiple myeloma. The five myeloma cell lines are stably growing at present in RPMI 1640 medium supplemented with 10% fetal bovine serum. They can also grow in a defined culture medium without serum. That these cell lines were, human myeloma cells was confirmed by the following findings. Ultranstructually, all five cell lines showed features characteristic of plasma cells. KMM-1 and KMS-11 cells secreted lambda and kappa chains into the culture medium, respectively, but the other cell lines produced no immunoglobulins. KMM-1 expressed cytoplasmic lambda antigen, KMS-5 showed cytoplasmic delta, and KMS-11 expressed surface kappa, whereas KMS-12-PE and KMS-12-BM cells showed no surface or cytoplasmic immunoglobulins. Regarding reaction with a monoclonal plasma cell antibody (PCA-1), four of the five lines were positive, the exception being KMS-5. Another monoclonal antibody (CD38), which also recognizes plasma cells, reponded to KMM-1, KMS-12-PE, and KSM-12-BM. KMS-5 cells expressed acute lymphoblastic leukemia antigens (CALLA). These data suggest that such lines as KMM-1, KMS-11, KMS-12-PE, and KMS-12-BM represent later stages of B-cell differentiation, and that KMS-5 represents a relatively early stage of B-cell differentiation. All the cell lines lacked Epstein-Barr virus nuclear antigen, showed abnormal karyotypes of human origin, and differed from each other in the isozyme patterns examined. Only KMS-5 was tumorigenic when transplanted subcutaneously into nude mice.  相似文献   
4.
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils.  相似文献   
5.
A 29 kb shuttle cosmid vector, pTYS507, was constructed from a cryptic Micromonospora griseorubida plasmid and the Escherichia coli cosmid pJB8. Subcloning of mycinamicin II biosysnthesis genes in pTYS507 led to the identification of a DNA region that could complement a mutant of M. griseorubida that lacked both hydroxylase and epoxidase activities. Nucleotide sequence and mutational analysis suggested that a single P-450-like protein catalyzes both reactions.  相似文献   
6.
Records of exotic turbellarian species found in Japan are reviewed from taxonomic and karyological viewpoints. Temnocephala minor Haswell, 1888, an ectocommensal on a freshwater crayfish of Australia, was found from culture ponds of Cherax tenuimanus (introduced from W. Australia) in Kagoshima Prefecture. T. minor had the chromosome number of 2x = 18 (2sm + 2m + 2m + 2sm + 2m + 2m + 2m + 2sm + 2m). The following 3 species of exotic freshwater triclads were recorded from tanks and ponds used for tropical fish culture: Dugesia austroasiatica Kawakatsu, 1985 (2x = 16), Dugesia tigrina (Girard, 1850) (2x = 16) and Rhodax? sp. (3x = 24; 3x = 24 &; 3x + 1LB + 1SB = 25 + 1SB). The following 3 species of exotic terrestrial triclads were recorded: Bipalium nobile Kawakatsu et Makino, 1982 (2x = 10), Bipalium kewense Moseley, 1878 (2x = 18), and Platydemus manokwari de Beauchamp, 1962 (n = 6, 2x = 12). An extensive occurrence of P. manokwari in the Southwest Islands of Japan may be due to an unexpected introduction of the animal in very recent years.  相似文献   
7.
 An association between eosinophils and tissue damage has been observed in numerous disorders. However, few reports have addressed the role of infiltrating eosinophils in gastric ulcer healing. The aim of this study was to investigate the kinetics and role of eosinophils infiltrating experimental chronic gastric ulcers in the rat. We developed a monoclonal antibody against human matrix metalloproteinase 1 (MMP1) purified from conditioned culture medium of human skin fibroblasts. Acetic acid-induced gastric ulcers were resected from rats on days 1, 3, 5, 10, 20, 40, and 180 after the days of induction (day 0). Tissue specimens were immunostained with this antibody and examined with an electron microscope. Few eosinophils were observed in the granulation tissue until day 20. By days 40 and 180, MMP1-positive eosinophils had increased in the granulation tissue of open ulcers. Azan staining revealed dispersed collagen fibers around infiltrating eosinophils. In contrast, scars demonstrated few eosinophils in fibrous tissue on days 40 and 180. Eosinophils which express MMP1 infiltrate granulation tissue at the chronic stage of gastric ulceration. The results suggest that eosinophils may play a role in tissue remodeling and deterioration of ulceration. Accepted: 18 March 1997  相似文献   
8.
Escherichia coli JM109(DE3) harboring expression plasmid pkAQNÆC30, which carries the Thermus protease aqualysin I (AQI) gene, was cultivated with glucose as a sole carbon source. The final cell concentration was over 15 g dry weight/l and the amount of AQI produced reached approximately 130 kU/ml broth. Moreover, by using two carbon sources, glucose and glycerol, the production yield was increased to over 200 kU AQI/ml, while suppressing the formation of inhibitory acetic acid.  相似文献   
9.
Summary The origin of mitotic cells was investigated histologically in chorionic tissue, metaphase plates of which were used for direct cytogenetic study. Mitotic figures were often observed in the Langhans' cell layers, but absolutely none were seen in the syncytium and stromal cells.  相似文献   
10.
A small yet significant increase of immunoassayable pancreatic somatostatin concentration (0.107 +/- 0.005 vs. 0.156 +/- 0.017 microgram/g at 24 hr, p less than 0.05) was found in rats, 24 hr as well as 7 days after treatment with a diabetogenic dose of streptozotocin (65 mg/kg BW). These animals were characterized by marked decreases of insulin in the pancreas without any significant changes in pancreatic glucagon concentration. These results suggest that an abrupt deprivation of insulin from islets results in an elevation of pancreatic somatostatin concentration, and that glucagon in the pancreas plays a minor role in determining pancreatic somatostatin concentration in rats with insulin-deprived diabetes of short duration.  相似文献   
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