摘要:

AbstractWe report the development of an in vitro screening system that can be used to identify new anticancer drugs that are specifically cytotoxic for dividing cells. The screening system takes advantage of the potential of many cell lines, including tumor cells, to stop dividing when they are plated at high cell density. The cytotoxic effects of anticancer drugs on dividing (i. e., cells plated at low cell density) and nondividing cells (i. e., cells plated at high cell density) is measured by the incorporation of51Cr. This in vitro system was evaluated by measuring the cytotoxic effects of the anticancer drugs cisplatin, thiotepa, doxorubicin, methotrexate, and vinblastine on the cell lines B/C-N, ME-180, and MCF-7. In this in vitro system the concentrations of the anticancer drugs that produced significant cytotoxicity on only dividing cells are similar to the concentrations that are used clinically. The fact that this in vitro system is rapid, simple, applicable to many cell types, and able to predict effective concentrations of anticancer drugs should make it useful for the screening of new anticancer drugs and for the design of preclinical studies.

ISSN:0735-7907    

DOI:10.3109/07357908909039855

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThe number of cytoplasmic vesicles in the capillary endothelium was determined by ultrastructural morphometry and correlated with the uptake of technetium-99m pertechnetate used in brain scintigraphy. Ten gliomas were studied for uptake rates of99mTcpertechnetate. Three gliomas from the different groups of uptake rates were quantitatively analyzed for cytoplasmic vesicle content. Capillaries of tumors without uptake had a low content of cytoplasmic vesicles, which was similar to that obtained in normal brain control. In tumors with low and moderate uptake rates, the cytoplasmic vesicles content increased significantly (p<0.05) by about 300% and 400%, respectively, as compared with that found in impermeable tumor and in normal brain. The correlation found between the cytoplasmic vesiculation of the endothelial cells in gliomas' capillaries and the uptake of99mTc pertechnetate suggests that pinocytosis might be a factor in the uptake of the radionuclide. The present findings might be applicable to treatment with hydrophilic chemotherapeutic agents in moderate and highly permeable tumors.

ISSN:0735-7907    

DOI:10.3109/07357908909039856

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractAlthough a higher incidence of medullary carcinoma of the thyroid is well known to occur in families with syndromes of multiple endocrine neoplasia (MEN II and III), an epidemiologic familial component has only very rarely been ascribed to papillary carcinoma. In this report we describe a mother and daughter presenting with neck masses at an early age and subsequently found to have metastatic papillary thyroid carcinoma documented on pathology following thyroidectomy. The occurrence of the neoplasm at an advanced stage in closely related individuals early in life suggests that underlying genetic factors may predispose to this malignancy. Familial papillary carcinoma of the thyroid may have a hereditary basis independent of its association with the syndromes of multiple polyposis and of multiple hamartomas, and thus may represent a new entity with characteristics which distinguish it as a distinct subset of the more common disease.

ISSN:0735-7907    

DOI:10.3109/07357908909039857

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThis report documents an association between lymphoblastic lymphoma and myasthenia gravis. Elevation of acetylcholine receptor antibody titer was an unusual marker for the lymphoblastic lymphoma. Following chemotherapy all symptoms of myasthenia gravis resolved and the acetylcholine receptor antibody titer normalized. The patient remains in complete remission off all therapy 20 months since the diagnosis of myasthenia gravis was made and 12 months after chemotherapy for her lymphoma.

ISSN:0735-7907    

DOI:10.3109/07357908909039858

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThe effect of immunosuppressive (IS) substance obtained from cancerous ascitic fluid on tumor growth and host immunity in plasmacytoma X5563-bearing C3H/He mice is described. IS substance given in three injections, before and after tumor inoculation caused: (a) enhanced tumor growth, (b) marked reduction in survival times, (c) inhibition on Con-A response of spleen cells. Depressed natural killer (NK) activity was observed in normal and tumor-bearing mice treated with IS substance. The data presented here suggest that IS substance suppresses both humoral and cellular immunoresponsiveness and tumor cells evade immune surveillance or immunologically mediated removal.

ISSN:0735-7907    

DOI:10.3109/07357908909039859

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThe importance of different lymphocyte cell populations in early recognition and destruction of tumor cells has not been fully established. Certainly natural killer cells and cytotoxic T lymphocytes are involved. Using a recently developed monoclonal antibody (GK 1.5) that has been shown to have in vivo cytotoxic activity directed at L3T4-bearing Tcells, we provide in these experiments evidence that T-helper cells are also important in early antitumor immunity. Development of progressive tumor growth after the subcutaneous inoculation of 105Lewis lung carcinoma (3LL) cells was greater in antibody-treated mice (13 of 20 treated mice vs. 6 of 21 controls). Nevertheless, in those animals that developed tumors, the latentcy period (time from tumor cell inoculation until tumor first palpable) and tumor growth rate were no different in antibody-treated mice when compared with control animals. In subsequent experiments, animals were exposed to irradiated tumor cells in Freund's adjuvant on three occasions and tumor growth was then assessed. Growth was slower in the sensitized group. Administration of GK 1.5, however, did not enhance the tumor growth rates in either the previously sensitized or control groups. The results suggest that T-helper cells might be of greater functional importance in early tumor cell recognition and destruction and of lesser importance in the restraint of tumor growth, once the tumor has become established.

ISSN:0735-7907    

DOI:10.3109/07357908909039860

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractA 69-year-old man receiving monotherapy for lung cancer with dichloromethotrexate (DCM), and without exposure to other chemotherapeutic agents or known ototoxic drugs, developed profound cochleovestibular dysfunction. The initial presentation was vestibular. This resolved, but unilateral hearing loss ensued and continued to progress to a total of 80 db loss in the low frequency range and 40 db in the high range, despite discontinuation of the drug. Because DCM may be used in combination with the known ototoxin cisplatin, the potential of DCM as an ototoxin should also be considered in such patients.

ISSN:0735-7907    

DOI:10.3109/07357908909039861

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractPrimary malignant solid tumors outside the central nervous system occur in fewer than 2/100,000 cases annually in children and young adults under the age of 21 years (1). Despite a steady improvement in survival of children with cancer over the past two decades, most significantly in Wilms' tumor, Hodgkin's disease, and leukemia, only modest improvement has been achieved in children with sarcomas.

ISSN:0735-7907    

DOI:10.3109/07357908909039862

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractIn 1978 the relative tranquility of the therapeutic approach to osteosarcoma was shattered when data from the Mayo Clinic questioned the validity of the historical control results of approximately 20% survival in patients with osteosarcoma treated with surgery alone (1,2). They demonstrated an increase in disease-free survival from 20 % to 40 % at the Mayo Clinic in patients treated with various methods of surgical ablation of the primary osteosarcoma during a 15-year period; and this compared favorably with their results with adjuvant chemotherapy. This finding led them to mount a randomized study of surgical ablation alone (18 patients) versus surgery and chemotherapy with high-dose methotrexate and vincristine (20 patients) (3). The results of this small randomized trial substantiated their nonrandomized observations; 42% of patients in both arms remained continuously disease free at 5 years. An additional 20% of patients with recurrent disease were salvaged after aggressive resection of pulmonary metastases, yielding a survival of 52 %.

ISSN:0735-7907    

DOI:10.3109/07357908909039863

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor

摘要:

AbstractThere is a constant interplay between scientific medicine and the sociocultural context in which it exists. Ideas for scientific pursuits, and decisions about where to channel energies and dollars for research, do not occur in a vacuum. They are influenced importantly by the social values and beliefs of their particular time and place.

ISSN:0735-7907    

DOI:10.3109/07357908909039864

出版商:Taylor&Francis    

年代:1989

数据来源: Taylor