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Biomedical subjects

C Jones

Publications and source records attributed to C Jones.

At least 685 records · Page 38Linked to original sources

Breast or bottle.

Explore the source record for details and available documents.

Attitude↗

Mechanism of rejection of virus persistently infected tumor cells by athymic nude mice.

Cell lines known to be tumorigenic in the nude mouse were modified by rendering them persistently infected (P.I.) with a variety of RNA viruses, including measles, mumps, vesicular stomatitis virus, and influenza. Although as few as 100 HeLa or BHK cells produced tumors in 100% of nude mice, as many as 2 x 10(7) of the same cells P.I. with viruses failed to produce tumors. An active host response responsible for restricting the growth of the P.I. cells was suggested by the findings of marked mononuclear cell infiltrates at the inoculation sites and the inability of irradiated nude mice to reject them. An analysis of the in vitro cytotoxic activity of spleen cells from normal nude mice indicated that: (a) P.I. cell lines, but not uninfected cell lines, were susceptible to spontaneous cytotoxicity; (b) in vivo inoculation of P.I. lines induced an enhanced cytotoxic activity for P.I. targets in vitro, and this induction was not specific either for inducing virus or cell line; and (c) the effector cell had the characteristics for natural killer (NK) cells. Although the specificity of recognition of the various P.I. cell lines remains unclear, cold competition experiments indicated that blocking the killing of one P.I. cell line, e.g. HeLa-measles, could be achieved only by unlabeled homologous cells, i.e. HeLa-measles, and not by uninfected cells or other P.I. lines. A variant subline of BHK cells P.I. with VSV was selected for its ability to withstand the rejection process in nude mice. These cells formed metastatic and invasive tumors in nude mice. Although they were the most potent inducers in vivo of NK cell activity against various P.I. targets, they were the most resistant of the P.I. lines to NK cell cytotoxicity in vitro. In this system there was a good correlation between tumor rejection in vivo and susceptibility to NK cells in vitro. The present results suggest that NK cells may play a significant role in both rejection of tumor cells, and in resistance to viruses, particularly persistent infections.

Animals↗

Long-term antiarrhythmic therapy with N-acetylprocainamide.

The effects of long-term NAPA therapy were evaluated in 6 patients with chronic PVCs known to respond to this drug during a previous placebo-controlled, dose-ranging trial. Underlying cardiac status was evaluated every six months by switching each patient from NAPA to placebo. Placebo period PVC frequency after one year of NAPA therapy was reduced, compared to baseline placebo values. Mean PEP/LVET, measured while the patients received placebo, was elevated at the beginning of the study but was normal after one year of NAPA therapy. Comparison of NAPA and placebo period observations indicated a reduction in PEP/LVET when NAPA therapy was begun. This effect, however, could not be demonstrated one year later when mean placebo period PEP/LVET was normal. The apparent dependence of this effect on underlying status of left ventricular function suggests that the initial reduction in PEP/LVET represents an an indirect effect of NAPA rather than a direct inotropic action. NAPA therapy was well tolerated by the 6 patients and ANA titers became abnormal in only one, in marked contrast to reported experience with procainamide.

Aged↗

Precise localization of human beta-globin gene complex on chromosome 11.

Cloned DNA probes were used in combination with a panel of five hybrid cell clones containing a series of different terminal deletions in human chromosome 11 to map precisely the human hemoglobin beta and delta chain structural genes contained on this chromosome. The region of deletion in each clone of the panel has been defined by biochemical, immunologic, and cytogenetic markers. DNA from clones containing successively larger terminal deletions was tested with appropriate DNA probes to determine the point on the chromosome at which DNA for these two closely linked hemoglobin genes is deleted. These genes, and by inference the closely linked G gamma and A gamma globin genes as well, have been assigned to the intraband region 11p1205 leads to 11p1208 on the short arm of chromosome 11, an interval containing approximately 4500 kilobases of DNA. The approach appears to have potential for even greater resolution and reasonably wide applicability for gene mapping.

Animals↗

Genetic and biochemical analysis of the a1 cell-surface antigen associated with human chromosome 11.

A highly versatile system for genetic, biochemical, and immunological analysis of human cell surface components has been developed using a human-Chinese hamster somatic cell hybrid containing chromosome 11 as its only human chromosome. This system lends itself to studies such as identification of human cell surface antigens and other genetic markers, regional gene mapping of these markers on chromosome 11, mutational analysis of these markers, and exploration of distribution of these antigens in normal and pathological human tissues. Genetic analysis of a1, one of the human antigens expressed by this hybrid, has been accomplished by subjecting a series of a1- variants to complementation analysis. These experiments have shown that the a1- variants behave in a recessive manner and that at least four genes, including three Chinese hamster genes, are needed for a1 antigen expression. Biochemical analysis has shown that a macroglycolipid isolated from human erythrocytes contains the a1 antigenic activity, so that genes coding for glycosyltransferases are required for its biosynthesis and may correspond to the complementation groups identified. The power of combined genetic, biochemical, and immunological approaches to understanding cell membrane molecules is demonstrated.

Antigens, Surface↗

Measurement of mutagenesis in mammalian cells.

A method using mammalian cells in vitro for detection and quantitation of mutagenic actions that appears to be useful for screening for carcinogenesis and genetic damage by environmental agents is presented. The method involves use of stable human--Chinese hamster ovary hybrid cells that have retained a single human chromosome not necessary for cell reproduction. Forward mutations are detected in genes necessary for production of specific human cell surface antigens. Such mutants form colonies in the presence of specific antisera and complement that destroy the unmutagenized cells. Use of the method is illustrated for the action of x-irradiation, N-methyl-N'-nitro-N-nitrosoguanidine, and caffeine. The method appears to be unique in that it permits assessment of lesions that cause loss of all or most of the chromosome as well as various localized gene mutations. The former action is particularly important because of the major involvement of chromosomal lesions in an extremely important class of human genetic disease.

Amniotic Fluid↗

Quality of life after major burns.

The only presently available method of measuring the outcome of major burns is the mortality rate. We have developed a scale, administered by interview and physical examination, with which the quality of life in survivors may be measured. In an initial group of 32 patients, we took each patient's own preinjury level of performance as a baseline. The size of the burn had no significant effect on the postburn score achieved. Substantial numbers of patients achieved levels superior to their preburn score. Improvement in scores did not begin until 12 months had elapsed from the time of injury. We feel that scales such as this will help determine what happens to patients after their injury, pinpoint areas of weaknesses in the burn program, and enable better comparison of performance between clinical facilities.

Burns↗

Cellular immune response to human cytomegalovirus. I. Lymphocyte transformation studies in the rabbit.

The lymphocyte transformation assay was used to monitor the cellular immune response of rabbits sensitized to cytomegalovirus (CMV). Peripheral blood lymphocytes from animals inoculated with purified virus were specifically stimulated by crude or twice-banded CMV. Blood cells from rabbits immunized to herpes simplex virus type 1 (HSV-1) responded to that antigen but not to CMV. Viable or heated CMV preparations stimulated unwashed blood cells as efficiently as washed cells. Furthermore, preincubation of stimulating antigen with anti-CMV serum did not prevent lymphocyte activation. Lymphoid cells readily stimulated by virus antigen were not stimulated by cells transformed by CMV or HSV-1.

Animals↗

[The future of nursing in Latin America].

The authors take up the subject with a retrospective review of the concepts of economic and social development, the health policy that has emerged in the last 25 years, and the salient characteristics of health practice and the training of nursing personnel. They interpret development in the health field and various approaches to the extension of the health services coverage that have been taken in the countries of Latin America through implementation of the strategies of primary care and community participation. Finally, they present several considerations on the future of nursing, with emphasis on a comprehensive view of the profession as an occupation and a social practice, after which they formulate a series of propositions that can serve as a basis for training of the nursing personnel that will be needed to serve society adequately.

Education, Nursing↗

Management of a complex diving accident.

After the accidental ascent of a diving bell from 80 m, one diver died from pulmonary barotrauma and the other-though grossly ill-survived. After recompression therapy, this diver was tetraplegic with evidence of patchy microcirculatory damage of brain, cord, liver, kidneys, and gut. All systems eventually returned to normal, except the spinal cord, mainly because of the post-recompression phase of management, in which pharmacological doses of steroids, hyperbaric oxygen, and dextran were used. Although function returned in the upper limbs, the diver remained paraplegic.

Accidents↗

Regional mapping of the gene for human lysosomal acid phosphatase (ACP2) using a hybrid clone panel containing segments of human chromosome 11.

A clone panel containing various segments of human chromosome 11 has been selected and use for regional assignment of the gene for human lysosomal acid phosphatase (ACP2) to the short arm of chromosome 11, in the region 11p11 leads to 11p12. Further evidence has also been presented to update the regional assignment of the gene for lactate dehydrogenase A (LDHA) to 11p12 leads to 11p13, and to support a previous assignment of the genes for the two components of the human cell-surface antigens of the SA11 (previously designated AL) group, SA11-1 and SA11-3 (previously designated AL-a1 and AL-a3), to 11pter leads to 11p13. This regional clone panel will be useful for rapid regional mapping of other genes assigned to chromosome 11.

Acid Phosphatase↗