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Biomedical subjects

M Woodside

Publications and source records attributed to M Woodside.

32 records · Page 2Linked to original sources
PubMed1992

Activation of the Na+/H+ antiporter during cell volume regulation. Evidence for a phosphorylation-independent mechanism.

A variety of cell types regulate their volume in anisotonic media by stimulating Na+/H+ exchange. Like growth factors, osmotic challenge activates the Na+/H+ antiport by increasing its sensitivity to intracellular [H+]. To investigate the molecular mechanism underlying this shift in pH sensitivity, the antiporter of 32P-labeled human bladder carcinoma cells and of Chinese hamster ovary cells was immunoprecipitated using antibodies raised against the cytosolic domain of the NHE-1 isoform of the Na+/H+ exchanger. Unlike the effects of growth promoters, activation of the antiport during volume regulation was not associated with increased phosphorylation. The possible coexistence of multiple antiporter isoforms was considered. The cytosolic alkalosis normally elicited by hypertonic media was found to be absent in Na+/H+ exchange-deficient fibroblasts. Responsiveness to osmotic challenge was restored by stable transfection of these cells with the cDNA encoding NHE-1. In these transfectants, phosphorylation of the antiporter was also unaffected during osmotic activation. The unchanged phosphate content of the antiporter might be explained by dephosphorylation of one site with concomitant phosphorylation at a different site. However, this possibility appears unlikely since phosphoamino acid analysis revealed that serine was the only residue phosphorylated in immunoprecipitated antiports of both control and osmotically stimulated cells. Moreover, phosphopeptide maps of control and hypertonically activated antiports were identical. These findings reveal a novel mode of activation of Na+/H+ exchange not requiring direct phosphorylation of the antiporter. We propose the existence of dual control of Na+/H+ exchange by phosphorylation-dependent and -independent mechanisms.

Animals↗
PubMed1991

Okadaic acid, a phosphatase inhibitor, induces activation and phosphorylation of the Na+/H+ antiport.

We determined the effect of okadaic acid (OA), a potent phosphoprotein phosphatase inhibitor, on the intracellular pH (pHi) of rat thymic lymphocytes and human bladder carcinoma cells. OA induced a rapid and sustained cytosolic alkalinization. This pHi increase was Na(+)-dependent and was inhibited by 5,N-disubstituted analogs of amiloride, indicating mediation by the Na+/H+ antiport. As described for other stimulants, such as mitogens and hypertonic challenge, activation of the antiport by OA is attributable to an upward shift in its pHi dependence. Accordingly, the alkalinization produced by the phosphatase inhibitor was not additive with that induced osmotically. Activation of the antiport by OA was accompanied by a marked increase in phosphoprotein accumulation, revealing the presence of active protein kinases in otherwise unstimulated cells. We considered the possibility that phosphorylation of the antiport itself or of an ancillary protein is responsible for activation of Na+/H+ exchange. Consistent with this notion, the alkalinization induced by OA was absent in ATP depleted cells. More importantly, immunoprecipitation experiments demonstrated increased phosphorylation of the antiport following treatment with OA. We conclude that, upon inhibition of phosphoprotein phosphatase activity, constitutively active kinases induce the activation of Na+/H+ exchange, possibly by direct phosphorylation of the antiport.

Adenosine Triphosphate↗
PubMed1981

Assessment of a secure/intensive care/forensic ward.

Recent trends in psychiatric hospitals have re-established the need for semi-secure, well-staffed acute wards. Such a ward is described and 400 consecutive admissions over a 34-month period reviewed. Using 13 beds all the acute patients requiring security and intensive treatment are managed from a total catchment area of 600,000. A wide range of referral agencies and diagnostic categories are encountered. Staff in the general psychiatric hospital where the ward is situated are satisfied with the service. A small group of chronically-disturbed patients require separate facilities.

Adult↗
PubMed1977

Family planning.

Explore the source record for details and available documents.

Adolescent↗
PubMed1976

Experiment in managing sociopathic behaviour disorders.

A ward catering for both sexes admitted patients with aggressive suicidal, or otherwise disturbed behaviour for observation and treatment until decisions could be made about their long-term needs. Patients were referred from the police, special hospitals, and the courts and some were transferred from other wards in the hospital. A third of the first 100 patients were admitted for forensic reasons. Twelve inmates were discharged to long-term accommodation for disturbed patients. The ward was intended to provide fairly short-term accommodation, though no time limits were set, and it was run as a medium secure unit. The ward was run by 16-18 nurses with support from medical teams, occupational therapists, and clinical psychologists. It has secured its status as a special unit within the hospital and will continue with the active support of the hospital staff.

Adolescent↗
PubMedDate not supplied

Bilateral neonatal Sturge-Weber-Dimitri disease: CT and MR findings.

The CT and MR features of cortical calcification and meningeal angiomatosis are typical of Sturge-Weber-Dimitri disease but are unusual in children less than 1 year of age. This case describes a child presenting with both of these features bilaterally in the neonatal period and represents an unusual presentation of this disorder.

Female↗
PubMedDate not supplied

Children of alcoholics: helping a vulnerable group.

There are 28 million children of alcoholics in the United States--1 of every 8 Americans. They are more likely than others to suffer from alcoholism and a wide range of physical, emotional, and mental health problems. It is probable that an inherited predisposition for the disease of alcoholism exists. Most children of alcoholics do not become alcoholic, but they are at increased risk for many other health problems. Records of the use of services provided by health maintenance organizations and of health insurance claims show that children of alcoholics use more medical and hospital services than other children. Children of alcoholics are more likely to have problems in school and to abuse alcohol and other drugs. Their mental and physical health problems persist into adulthood. Clinical findings show that life in an alcoholic family is often characterized by pain, guilt, fear, tension, and insecurity. Children do not know that alcoholism is a disease which they cannot cause, control, or cure. Because alcoholism is a family secret, children rarely seek help, even as adults. Because the children of alcoholics are in many medical and social service systems, greater awareness and understanding by health and human service professionals can lead to identification and help for this vulnerable group. It is critical for family physicians, obstetricians, pediatricians, nurses, social workers, hospital staff, and others to incorporate questions about family alcoholism in routine screening procedures for youth and adults. Recommendations and useful materials are discussed.

Adult↗