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Biomedical subjects

J M Watson

Publications and source records attributed to J M Watson.

At least 145 records · Page 8Linked to original sources
PubMed1992

Nosocomial transmission of tuberculosis in AIDS care centres.

Outbreaks of tuberculosis in centres for the care of patients with AIDS, including outbreaks involving drug-resistant strains of Mycobacterium tuberculosis, have been reported from a number of countries and present special problems. Transmission of infection may be facilitated by procedures commonly used with AIDS patients, and recognition of the diagnosis in an infectious case may be delayed. Although no similar outbreaks have been identified in the United Kingdom, it may be timely to review the policy and procedures used in this country in the light of experience elsewhere.

AIDS-Related Opportunistic Infections↗
PubMed1992

Gene mapping studies confirm the homology between the platypus X and echidna X1 chromosomes and identify a conserved ancestral monotreme X chromosome.

The identification of the sex chromosomes in the three extant species of Prototherian mammals (the monotremes) is complicated by their involvement in a multivalent translocation chain at the first division of male meiosis. The platypus X chromosome, identified by the presence of two copies in females and one in males, has been found to possess a suite of genes that have been mapped to the X chromosomes of all eutherian and metatherian mammals. We have extended gene mapping studies to a member of the only other extant monotreme family, the echidna, which has a G-band equivalent X1 chromosome, as well as a smaller X2. We find that the five human X-linked genes (G6PD, GDX, F9, AR and MCF2) map to the echidna X1 chromosome in locations equivalent to those on the platypus X. These results confirm that the echidna X1 is the original X chromosome in this species, and identify a conserved ancestral monotreme X chromosome.

Animals↗
PubMed1992

Stimulation of ovarian tumor cell proliferation with monocyte products including interleukin-1, interleukin-6, and tumor necrosis factor-alpha.

OBJECTIVE: We investigated whether monocyte-derived factors could stimulate the growth of ovarian cancer cells. STUDY DESIGN: Human peripheral blood monocytes or human monocyte-like cell lines THP-1 and U-937 were cultured with or without macrophage colony-stimulating factor, lipopolysaccharide, or phorbol myristate acetate. Culture supernatants or recombinant cytokines were assayed for growth stimulation of ovarian cancer cell lines by tritium-thymidine incorporation and direct cell counts followed by statistical analysis with Student t test. RESULTS: Conditioned medium from peripheral blood monocytes or from THP-1 or U-937 cells stimulated ovarian cancer cell growth. Interleukin-1 alpha, tumor necrosis factor-alpha, and interleukin-6 also stimulated ovarian cancer cell growth, whereas macrophage, granulocyte, and granulocyte-macrophage colony-stimulating factor did not. Concentrations of tumor necrosis factor, interleukin-1, and interleukin-6 in conditioned medium could not account for all the growth stimulation, and activity remained after neutralization of tumor necrosis factor, interleukin-1, and interleukin-6 with antibodies. CONCLUSIONS: Interleukin-1, interleukin-6, tumor necrosis factor, and additional monocyte factor(s) could provide paracrine growth stimulation when monocytes are attracted to ovarian cancers that produce macrophage colony-stimulating factor.

Cell Division↗
PubMed1992

The evolution of human chromosome 21: evidence from in situ hybridization in marsupials and a monotreme.

We have mapped five human chromosome 21 (HSA 21) markers in marsupials and a monotreme, two major groups of mammals that diverged from eutherians 130-150 and 150-170 million years before present (MYrBP), respectively. We have found that these genes map to two distinct autosomal sites, one containing SOD1/CBR/BCEI and the other containing ETS2/INFAR, in the marsupials Macropus eugenii and Sminthopsis macroura (which belong to orders that diverged 40-80 MYrBP), as well as in the monotreme Ornithorhynchus anatinus (the platypus). Since marsupials and monotremes diverged independently from eutherians, these data suggest that HSA 21 genes were originally located in two separate autosomal blocks. In another Sminthopsis species, SOD1 is linked to TRF (a marker on HSA 3q), suggesting that the ancestral SOD1/CBR/BCEI region also included HSA 3 markers. We suggest that these blocks became fused early in the eutherian evolution to form a HSA 3/21 chromosome, which has remained intact in artiodactyls, but has been independently disrupted in both the primate and rodent lineages.

Animals↗
PubMed1992

Presence of interleukin 10 (IL-10) in the ascites of patients with ovarian and other intra-abdominal cancers.

Typically, ovarian cancer remains restricted to the peritoneal cavity. Because of this unique localization, the study of ovarian cancer is particularly suitable for immune analysis and for the development of immunotherapy. Here we report that peritoneal fluid from patients with ovarian or other intra-abdominal cancers contained significantly elevated levels of interleukin 10 (IL-10) (542 +/- 77 pg/ml, N = 35), compared with peritoneal fluid from patients with benign gynecological conditions (34.2 +/- 7.5 pg/ml, N = 63) (P < 0.001). Peritoneal fluid IL-10 levels did not correlate with histology, tumor stage, grade, or prognosis. IL-10 levels were also elevated in the serum of patients with intra-abdominal cancer (1353 +/- 906, N = 8). Established ovarian cancer cell lines (N = 5) did not produce any detectable IL-10. Investigation of the cell surface phenotype of the cells in the peritoneal cavity indicated the presence of significant amounts of activated immune cells. The presence of cytokines such as IL-10 in the peritoneal cavity of ovarian cancer bearing patients could be important in the growth and development of cancer, more specifically, in relation to host immune responsiveness.

Antigens, CD↗
PubMed1992

Autosomal localization of the amelogenin gene in monotremes and marsupials: implications for mammalian sex chromosome evolution.

We have determined by Southern blot analysis that DNA sequences homologous to the AMG gene probe are present in the genomes of both marsupial and monotreme mammals, although adult monotremes lack teeth. In situ hybridization and Southern analysis of cell hybrids demonstrate that AMG homologues are located on autosomes. In the Tammar Wallaby, AMG homologues are located on chromosomes 5q and 1q and in the Platypus, on chromosomes 1 and 2. The autosomal location of the AMG homologues provides additional support for the hypothesis that an autosomal region equivalent to the human Xp was translocated to the X chromosome in the Eutheria after the divergence of the marsupials 150 million years ago. The region containing the AMG gene is therefore likely to have been added 80-150 million years ago to a pseudoautosomal region shared by the ancestral eutherian X and Y chromosome; the X and Y alleles must have begun diverging after this date.

Amelogenin↗
PubMed1992

Mapping human X-linked genes in the phalangerid marsupial Trichosurus vulpecula.

We mapped 15 human X-chromosome markers in the common brush-tailed possum, Trichosurus vulpecula (Kerr), which represents the Australian marsupial family Phalangeridae. In situ hybridization was used to localize highly conserved human X-linked genes to chromosomes of T. vulpecula diploid lines. Ten genes located on the long arm of the human X (human Xq genes) all mapped to the possum X chromosome. However, all five genes located on the short arm of the human X (human Xp genes) mapped to autosomes. These findings confirm our previous work, which showed that the X chromosome in macropodid and dasyurid marsupials bears all the human Xq genes but none of the human Xp genes studied. This suggests that the marsupial X is highly conserved, but its gene content reflects that of only part of the eutherian X, a result consistent with our hypothesis that an autosomal region was added to the X early in eutherian divergence.

Animals↗
PubMed1992

Mycobacterium bovis in England and Wales: past, present and future.

This report reviews the literature concerning tuberculosis resulting from infection with Mycobacterium bovis in man and cattle and summarises data derived from surveillance of M. bovis in England and Wales from 1986 to 1990. Of the 228 isolates of M. bovis examined in this period, 122 (53%) were from patients aged over 60 years and are largely the result of reactivation of infection acquired prior to the institution of control measures. However, eight isolates (3.5%) were from patients aged less than 30 years. The potential sources for these presumed primary infections include the few remaining cattle infected with M. bovis or infectious human cases in the United Kingdom. However, infections acquired abroad, especially in immigrants, may account for some of these cases. Outbreaks of tuberculosis due to M. bovis continue to occur in cattle. Wild animals, particularly badgers, have been implicated as reservoirs of the infection. However, man may also prove to be an important reservoir of M. bovis for cattle as well as humans.

Animals↗
PubMed1992

Detection of interleukin-6 in human follicular fluid.

OBJECTIVE: To determine if interleukin-6 (IL-6) is a normal constituent of human follicular fluid (FF) after ovarian hyperstimulation and to assess whether IL-6 levels differ in conditions associated with immunological causes of infertility. DESIGN: After ovarian hyperstimulation for an in vitro fertilization (IVF) treatment cycle, FF samples were obtained at the time of oocyte retrieval. SETTING: Referral center at a tertiary care hospital. PATIENTS: Thirty women referred for IVF, including 10 patients with significant titers (greater than 40%) of antisperm antibodies and 10 with pelvic endometriosis. Ten patients with tubal infertility without antisperm antibodies or endometriosis served as controls. MAIN OUTCOME MEASURES: Analysis of FF levels for IL-6 using both bioassay and immunoassay. RESULTS: Bioactive (range 0.32 to 32.2 U/mL) and immunoreactive (range 0.34 to 13.6 ng/mL) IL-6 levels were detected in FF of all subjects after ovarian hyperstimulation. Follicular fluid IL-6 levels were substantially higher (3 to 30-fold) than that reported in serum. There was no difference in the mean concentrations of IL-6 levels between patients with antisperm antibodies, endometriosis, or tubal infertility. CONCLUSIONS: Bioactive and immunoreactive IL-6 are present in human FF after ovarian hyperstimulation, supporting a potential autocrine or paracrine role within the follicular microenvironment.

Adult↗
PubMed1992

Elevated interleukin-6 levels in peritoneal fluid of patients with pelvic pathology.

OBJECTIVE: To determine if interleukin 6 (IL-6) is a normal constituent of peritoneal fluid (PF), and if various types of pelvic pathology influence its presence within the PF microenvironment. STUDY DESIGN: Peritoneal fluid from 73 women obtained at the time of laparoscopy was examined for the presence of IL-6 using an IL-6 specific sandwich enzyme-linked immunosorbent assay. Thirty-nine patients had pelvic endometriosis, 17 had nonendometriotic pelvic adhesive disease, and 17 subjects undergoing tubal sterilization without evidence of pelvic pathology served as controls. RESULTS: Immunoreactive IL-6 was observed in the PF of all 73 subjects (range 0.26 to 11.16 ng/mL). The mean concentration of IL-6 was higher in women with nonendometriotic pelvic adhesions as compared with control subjects (1.28 +/- 0.16 versus 0.80 +/- 0.06 ng/mL, P less than 0.03). There was no difference in the mean peritoneal concentrations of IL-6 between women with endometriosis (1.16 +/- 0.28 ng/mL) and controls, P = 0.38. Twenty-seven of 73 patients (37%) demonstrated elevated levels (greater than 1.0 ng/mL) of IL-6. Patients with pelvic adhesions were significantly more likely to have elevated concentrations of IL-6 than controls (10/17 [59%] versus 3/17 [18%], P less than 0.02). Alternatively, the percentage of patients with elevated IL-6 concentrations did not differ between patients with endometriosis or controls (14/39 [36%] versus 3/17 [18%], P greater than 0.10). CONCLUSIONS: These findings demonstrate that IL-6 is a normal constituent of PF and that elevated levels are found in many patients with pelvic adhesions.

Adult↗
PubMed1991

Sex chromosome evolution: platypus gene mapping suggests that part of the human X chromosome was originally autosomal.

To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in all mammals, revealing that this region was part of an ancient mammalian X chromosome. However, we now report that several genes located on the short arm of the human X chromosome are absent from the platypus X chromosome, as well as from the marsupial X chromosome. Because monotremes and marsupials diverged independently from eutherian mammals, this finding implies that the whole human X short arm region is a relatively recent addition to the X chromosome in eutherian mammals.

Animals↗
PubMed1991

"Heartstart Scotland"--initial experience of a national scheme for out of hospital defibrillation.

OBJECTIVE: To determine the outcome of out of hospital defibrillation in Scotland during the year after the introduction of automated external defibrillators in October 1988. DESIGN: Retrospective analysis of ambulance service reports and hospital records. SETTING: Scottish Ambulance Service and acute receiving hospitals throughout Scotland. MAIN OUTCOME MEASURES: Delay from cardiac arrest to first defibrillator shock; vital state on arrival at hospital accident and emergency department; survival to hospital discharge. RESULTS: During the study period 268 defibrillators were purchased by public subscription and 96% of the 2000 ambulance crew underwent an eight hour training programme in cardiopulmonary resuscitation and defibrillation. A total of 1111 cardiac arrests were recorded, and defibrillation was indicated and undertaken in 602 (54%) patients, mean age 63 (range 14-92) years. A spontaneous pulse was present on arrival at hospital in 180 (30%) of the defibrillated patients, and 75 (12.5%) were subsequently discharged alive. As expected, the likelihood of survival was inversely related to the delay from the onset of cardiac arrest to the time of the first shock and was greater in the case of witnessed arrest. If ventricular fibrillation occurred after the arrival of the ambulance, survival to discharge was 33%. CONCLUSIONS: An effective scheme for out of hospital defibrillation can be introduced rapidly, and with limited training implications and costs, by the use of automated external defibrillators in ambulances.

Adolescent↗
PubMed1991

Mammalian sex chromosomes: evolution of organization and function.

Comparisons of chromosome size, morphology and gene arrangements between mammals of different species permit us to deduce the genome characteristics of the common ancestor, and to chart the changes that have occurred during the divergence of the two lineages. The more distantly related are the species compared, the more remote the common ancestor whose characteristics can be deduced. This means that, providing there are sufficient similarities to warrant comparison, the more divergent the species compared, the more significant the contribution to our understanding of the organization of an ancestral mammalian genome and the process of mammalian genome evolution. One of the genetic surprises of the last decade was the discovery that, although gross karyotypes of distantly related orders of eutherian mammals (e.g. cat, cow, rabbit, man) have diverged extensively, gene mapping studies reveal the presence of large chromosome segments conserved across at least 60 million years (O'Brien et al. 1988). This finding makes it worthwhile to extend genetic comparisons to the two groups of mammals most distantly related to eutherian mammals--marsupials and monotremes. Here we will review comparisons of the sex chromosomes in these three major groups of extant mammals, and show how they have led us to a new view of the evolution of mammalian sex chromosome organization and function in sex determination and X chromosome inactivation.

Animals↗
PubMed1991

Serum interleukin-6 levels correlate with disease status in patients with epithelial ovarian cancer.

Interleukin-6 is a pleiotropic cytokine with a wide range of effects, including induction of B-cell and cytotoxic T-cell differentiation, and induction of acute phase reactant production by hepatocytes. Interleukin-6 also can act as an autocrine growth factor in malignancy. Various cell types produce interleukin-6, including T and B cells, monocytes, fibroblasts, and some solid tumor cells. In previous work we detected the production of substantial amounts of interleukin-6 by human ovarian cancer cells, including the ovarian cancer cell lines CAOV-3, OVCAR-3, and SKOV-3, and several primary ovarian tumor cultures. In this study we retrospectively examined 90 separate serum specimens for interleukin-6 in 36 patients with epithelial ovarian cancer. The mean serum interleukin-6 concentration of those ovarian cancer patients with macroscopic disease (n = 57) was 0.26 +/- 0.04 U/ml (mean +/- SEM). Healthy adult donors have interleukin-6 serum levels of 0.12 +/- 0.03 U/ml. Sixteen of 21 ovarian cancer patients with macroscopic disease (76%) had elevated (greater than 0.20 U/ml) levels of serum interleukin-6, with levels approaching 1 U/ml in some patients (p less than 0.01). Of those nine patients with bulky tumor (residual greater than 2 cm), eight (89%) had an elevated interleukin-6 level (mean, 0.31 +/- 0.05), while eight of 12 (66%) with minimal residual disease (less than 2 cm) had elevated levels. Only two of 15 (13%) patients who were in clinical remission and who had microscopic disease had elevated values. Of the 36 patients, 22 were CA 125 negative (less than 35 U/ml), and of these, four had elevated interleukin-6 levels. Of the 14 patients with an elevated CA 125 level, 12 (86%) had elevated interleukin-6 levels. In those 16 patients in whom serial levels of interleukin-6 were measured, rising levels were found over a 3 to 4 month interval in nine (56%); this correlated with tumor progression. Furthermore, the subsequent survival of patients was shown to correlate with the level of interleukin-6, such that patients whose levels were elevated greater than 0.20 U/ml interleukin-6 survived a mean of 12.5 months, compared with 27.2 months for patients with normal levels (p less than 0.001). These data support the concept that interleukin-6 may be a useful tumor marker in some patients with epithelial ovarian cancer, as it correlates with the tumor burden, clinical disease status, and survival.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1991

Genes on the short arm of the human X chromosome are not shared with the marsupial X.

Eight genes located on the short arm of the human X chromosome (MAOA, SYN1, OAT, OTC, CYBB, DMD, ZFX, POLA) have been mapped in several marsupial species by cell hybrid analysis and/or in situ hybridization using probes derived from human cDNA. Seven appear to be autosomal in all marsupial species examined. The eighth, CYBB, detected a site on the X, as well as major autosomal sites. Although these genes are not conserved on the X chromosome in marsupials, at least some of them are arranged together in autosomal clusters. The autosomal location of human Xp genes in marsupials could mean that this region either was lost from a large ancestral X chromosome in the marsupial lineage or was acquired by a small ancestral X (and perhaps Y) in the eutherian lineage. Either explanation demands that the region was not subject to X chromosome inactivation in a common ancestor 120-150 MyrBP.

Animals↗