摘要:

Widespread application of intralesional tritiated thymidine injection to obtain cell kinetic data in lung cancer is described. Thymidine-labeling indices were obtained in 28 patients with lung cancer, and the data analyzed by histologic cell types. The mean and median labeling indices were highest in small-cell carcinoma of the lung. Mean values were significantly higher in the small-cell and in the large-cell undifferentiated carcinoma groups than in the adenocarcinoma and epidermoid carcinoma. On the other hand, a labeled mitosis curve in a patient with small-cell carcinoma yielded a duration of DNA synthesis of 18.8 h; not unlike those obtained for other solid tumors. According to our concepts of tumor growth, these findings suggest that the fraction of proliferating cells may be significantly higher in the small-cell and large-cell undifferentiated carcinomas than in the more differentiated cell types of bronchogenic cancer. Knowledge of the growth fraction of these cancers may have implications in directing therapeutic approaches and in interpreting features of the natural history of the disease.

ISSN:0030-2414    

DOI:10.1159/000224976

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The value of a screening test for cytotoxic chemotherapeutic agents in the treatment of advanced malignant disease is assessed by comparing the performances of 32 patients whose treatment followed closely the test recommendations with that of 31 patients whose treatment did not follow the predictions. The significant improvement in short-term prognosis (p = 0.004) indicates that the test is of clinical value. The limitations of retrospective analysis are discussed in detail.

ISSN:0030-2414    

DOI:10.1159/000224977

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The controversies on 5-fluorouracil (5-FU) appear to be gradually culminating in two divergent groups of workers. One group uses low doses of the drug administered weekly and the other group prefers high doses, the so-called standard loading dose system or its modification. The present study reports impressions with a modified repeated protracted high dose schedule of 5-FU in 325 patients with far-advanced solid malignancies treated in Bangladesh with 20% objective and 40% subjective responses. The morbidity rate was high but the protraction and the vigilance perhaps have kept the mortality rate at 1.5%. About 14% of 120 patients with gastrointestinal metastatic cancers have survived more than 1 year and 8% beyond 2 years. Review of the literature on 5-FU reveal a tendency towards better response rates with higher drug concentrations particularly in the tumor-bearing area. It is noted that some prolonged survivors are always recorded by workers using high dose schedules but not yet by those using weekly schedules. It is imperative to wait for both short- and long-term results of the controlled trials before valid conclusions can be made.

ISSN:0030-2414    

DOI:10.1159/000224978

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

B-16 melanomas grown for 13 and 22 days after transplantation in mice were utilized in studies of subcellular distribution of tyrosinase activity and tyrosinase isozyme patterns. The tyrosinase activity utilizing L-tyrosine-14C was higher in the younger than in the older melanomas. The percent of total activity distributed in the 144,000 g supernatant was 38% for the former and 46% for the latter. Both melanomas had higher percentage of activity confined in the pellet obtained by centrifuging the crude homogenate at 600 g. The digestion of P 600 g pellet by lipase liberated tyrosinase activity which was twofold of the activity originally counted in the pellet. Five isozymes were observed in the soluble tyrosinase and two in the solubilized tyrosinase.

ISSN:0030-2414    

DOI:10.1159/000224979

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Plasma samples obtained from 74 patients with malignant disease were assayed for their ability to suppress or block the mixed lymphocyte reactivity of random normal donors. 24 of the 74 patients investigated had evidence of mixed lymphocyte culture blocking factor activity (MLC-BFA). 19 of 33 patients with disseminated disease had evidence of MLC-BFA whereas in only 5 of 41 patients with localized disease was evidence of BFA found. There was a relationship between a history of previous blood transfusion in the 6-month period prior to study and the presence of MLC-BFA in patients’ plasma. Excluding this group of patients, where previous transfusion might have been responsible for MLC-BFA and excluding, too, that group of patients with a history of past pregnancy, there remained still 11 patients with evidence of BFA in their plasma. Nine of these 11 had widely disseminated and progressive disease. MLC-BFA was found in both IgM and IgG fractions of plasma. Plasma with MLC-BFA was found to suppress normal in vitro lymphocyte responses to mitogens PWM and PHA. The MLC-BFA assay utilized in this work may provide the means of monitoring cancer patients in order to detect ‘blocking’ ant

ISSN:0030-2414    

DOI:10.1159/000224980

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

5-Azacytidine (NSC-102 816) was prepared synthetically and independently isolated from the culture filtrate of Streptoverticillium ladakanus. It is an s-triazine analogue of cytidine possessing a broad spectrum of biological effects. In mammalian tissue it is phosphorylated to 5-azacytidine 5´-phosphates and incorporated into different species of RNAs and into DNA. 5-Azacytidine 5´-monophosphate inhibits orotidine 5´-phosphate decarboxylase blocking thus the de novo pyrimidine synthesis. Following the administration of 5-azacytidine a rapid breakdown of liver polyribosomes has been observed; furthermore, in different systems a profound inhibitory effect of the drug on the maturation of ri-bosomal RNA has been found. 5-Azacytidine interferes with different induced liver enzymes ; in some cases their activity is elevated since the rate of enzyme degradation is decreased. The cytostatic effect of the drug is directed primarily against lymphatic leukemia although some recent reports indicate its action also against human solid tumours. Chemotherapy of leukemic mice by 5-azacytidine results simultaneously in the depressed synthesis of liver and spleen polyamines. 5-Azacytidine exhibits further mutagenic, abortive, immunosuppressive, antimitotic, radioprotective and virostatic effects. The drug also affects DNA and protein synthesis in embryonic tissues, cells in tissue culture, regenerating livers, in bacteria and phages. The changes associated with the emergence of resistance towards 5-azacytidine are associated with the decreased activity of uridine kinase in mouse leukemia cells. On the contrary, in adult rat livers 5-azacytidine administration leads to the increased activity of this enzyme. Different authors have used 5-azacytidine as a tool for the study of biochemical mechanisms connected with a cell proliferation and divisi

ISSN:0030-2414    

DOI:10.1159/000224981

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Serum from patients with carcinoma of the prostate were observed to possess a factor(s) capable of inhibiting the migration of allogeneic leukocytes in the direct leukocyte migration test. Maximum inhibitory activity was obtained with those sera possessing an elevated level of an as yet unidentified factor(s) in the α2-globulin fraction of the serum of these patients. The presence of such a factor(s) may prevent interaction between leukocyte-inhibiting factor sensitive cells and tumour cells and emphasizes the role of humoral inhibitory or ‘immunoregulatory’ factors, such as α2-globulin, on immunologic responses as blastogenesis and inhibition of leukocyte migration, as potential abrogators of mechanisms of host-resistance, e.g., immunologic surveil

ISSN:0030-2414    

DOI:10.1159/000224982

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Rats with Walker tumor injected intramuscularly in both hind legs and subjected to forced swimming for 15 min daily for 10 days displayed a trend toward decreased lesion size, especially in older intact animals as compared to unexercised intact or bilaterally adrenalectomized controls. Secondary tumor nodules occurred at the lower abdominal or inguinal areas and appeared to be more extensive in the older exercised rats. The survival rates offorced exercised rats bearing Walker tumor cortically did not differ significantly from the respective controls as was also the case with adult BDF1 mice with intraperitoneal or cortical L1210 tumor and subjected daily to electroshock at 0.25 mA for 15 min.

ISSN:0030-2414    

DOI:10.1159/000224983

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The selective action of nonantigenic tissue extracts on malignant cells was demonstrated using tissue culture techniques. The mitotic index of three strains of neoplastic cells was significantly reduced by the use of extracts which previously had proven effective in adversely affecting the development of spontaneous neoplasms. Under the same conditions the division rate of normal cells in tissue culture was not affected by the extracts. The malignant cells used were the Krebs 2, Sarcoma 180 and the L1210 leukemia. The normal cells were the L929 fibroblasts and epithelial-like cells from bone marrow and corneal tissue.

ISSN:0030-2414    

DOI:10.1159/000224984

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Intraperitoneal administration of hormones or of certain neuropharmacological agents does not affect initial blastema formation in adult newts (Notophthalmus viri-descens). Hormonal treatment accelerates the onset of the morphogenetic phase of regeneration. In contrast, treatment with chlorpromazine (alone or with growth hormone), gua-nethidine, or atropine retards or represses the onset of morphogenesis. These results suggest that some interaction between the nervous and endocrine systems is required in promoting the proliferative and the morphogenetic stages of forelimb regeneration.

ISSN:0030-2414    

DOI:10.1159/000224985

出版商:S. Karger AG    

年代:1974

数据来源: Karger