PubMed Health⌕ Search

Biomedical subjects

E L Watson

Publications and source records attributed to E L Watson.

48 records · Page 3Linked to original sources
PubMed1977

Properties of the HCO-3-stimulated Mg2+ -ATPase activity in red cell membranes.

The HCO-3-stimulated Mg2+ -ATPase activity in red cell ghost fragments was investigated. Increasing the HCO-3 concentration in the incubation medium resulted in increased ATPase activity. NaHCO3 appeared to be more effective than KHCO3 in this regard. The ATPase activities were slightly stimulated by increases in ionic strength and utilized ITP almost as readily as ATP. A Mg/ATP ratio of 1.0 and a pH of 7.6 yielded maximum activity. These properties are of interest since the present enzyme is the only unquestionable instance where a HCO-3 ATPase is located in the surface membrane of a cell.

Adenosine Triphosphatases↗
PubMed1976

Diphenylhydantoin effects on salivary secretion and microsomal calcium accumulation and release.

Diphenylhydantoin inhibited calcium uptake into dog submandibular microsomes at concentrations of 0.05 mM and greater but did not affect calcium release; mesantoin and hydroxyphenyl-phenylhydantoin were without effect. Diphenylhydantoin (20 mg/kg) given i.v. significantly reduced, and mesantoin slightly reduced secretion from submandibular and parotid glands, but hydroxyphenyl-phenylhydantoin was without effect. These data suggest that the reduced secretory volume produced by diphenylhydantoin may be related to its effect on transmembrane calcium movements.

Adenosine Triphosphatases↗
PubMed1975

Effects of ruthenium red and KCL on responses of guinea pig umbilical veins.

5-Hydroxytryptamine (10(-5) M), norepinephrine (10(-5) M) and acetylcholine (10(-5) M) induced maximal contractions in isolated guinea pig umbilical vein strips. Pretreatment with ruthenium red (2.7--90 mug/ml) for ten minutes reduced 5-hydroxytryptamine and norepinephrine responses in a dose-related manner but did not affect acetylcholine-induced responses. Ruthenium red alone did not produce contractions. In the presence of KC1 (125 MM) the responses to norepinephrine and acetylcholine were enhanced significantly. The sensitivity of umbilical veins to ruthenium red may be useful in determining to what extent various vasoactive agents utilize extracellular calcium to induce contractions.

Acetylcholine↗
PubMedDate not supplied

The measurement of mandibular cortical bone height in osteoporotic vs. non-osteoporotic postmenopausal women.

The asymptomatic progression of osteoporosis, in conjunction with the possibility of catastrophic disability, makes this disorder a major public health priority. Various body sites, including the mandible, have shown susceptibility to decreasing bone density. In 1986, Benson et al. proposed a radiomorphometric technique called the Panoramic Mandibular Index (PMI) as an inexpensive noninvasive dental technique for osteoporosis screening, although no osteoporotic subjects were included in their study. The purpose of our study was to determine whether osteoporotic postmenopausal women would show a decrease in mandibular cortical bone height, as measured by the PMI index, when compared with nonosteoporotic postmenopausal women. Seventy-two Caucasian females (33 cases/39 controls), aged 54-71 years old, were selected through records and screening via a dual-energy x-ray absorptiometry scan (LUNAR-DEXA). ANOVA analysis indicated no differences in the mean PMI between case and control groups (0.37 +/- 0.15 and 0.38 +/- 0.13, respectively; p = 0.69). Other techniques, such as computer digitized radiography should be explored to test the validity of the PMI.

Absorptiometry, Photon↗