Search PubMed⌕ Search

Biomedical subjects

J Edwards

Publications and source records attributed to J Edwards.

At least 289 records · Page 16Linked to original sources

Contextual effects on lingual-mandibular coordination.

Coordination between intrinsic and jaw-related components of tongue blade movement during the articulation of the alveolar consonant /t/ was examined across changes in phonetic context. Tongue-jaw interactions included compensatory responses of one articulatory component to a contextual effect on the position of the other articulatory component. A similar reciprocity has been observed in studies that introduced artificial perturbation of jaw position and studies of patterns of token-to-token variability. Thus the lingual-mandibular complex seems to respond in a similar manner to at least some natural and artificial perturbations.

Adult↗

Endometrial lymphoid tissue: an immunohistological study.

Lymphoid tissue of the endometrium was analysed by histological, immunohistological, and electron microscopical methods in 10 healthy uteri. A panel of monoclonal antibodies recognising macrophages (OKMI), HLA-DR antigen, B lymphocytes, T lymphocytes and their subsets, and dendritic reticulum cells was used in a two stage indirect immunoperoxidase labelling technique. Endometrial lymphoid tissue showed a remarkably consistent pattern of labelling in all cases. Lymphoid tissue was present in three sites: namely, (i) intraepithelial lymphocytes (predominantly T lymphocytes with occasional macrophages) associated with periglandular and sub-epithelial HLA-DR+, OKMI+ macrophages; (ii) interstitial lymphocytes and macrophages; (iii) lymphoid aggregates in the stratum basalis. These were composed mainly of T lymphocytes with a few B lymphocytes. Dendritic reticulum cells were found in those occasional lymphoid aggregates in which germinal centres were present. These features suggest that endometrial lymphoid tissue has many of the hallmarks of mucosal associated lymphoid tissue as found elsewhere in the body--for example, the bronchus and intestine. Endometrial lymphoid tissue appears to be unique, however, in that most of the stratum functionalis in which it is situated shows cyclical shedding during the menstrual cycle.

Adolescent↗

Scopolamine and the sensory conditioning of hallucinations.

By means of a sensory conditioning procedure, auditory 'hallucinations' were produced in a set of subjects by pairing a light and a tone. The effect of two doses of scopolamine on the occurrence of these hallucinations was investigated, and the results showed that they were more likely to occur after scopolamine than when subjects had received a placebo. This change was attributed to the impairment of information processing induced by scopolamine.

Acoustic Stimulation↗

Gas-liquid chromatographic determination of total phenylacetic acid in urine.

A gas-liquid chromatographic procedure to measure total phenylacetic acid in urine is described. The method is simple, rapid, and reliable. Normal subjects (N = 48) excreted 141.1 +/- 10.1 mg/24 h. Untreated depressed patients (N = 42) excreted 102.77 +/- 15.9 mg/24 h. The difference in the means is significant and supports the role of phenylacetic acid as a biological marker in certain kinds of mental illnesses.

Chromatography, Gas↗

Cytogenetic analysis of a segment of the Y chromosome of Drosophila melanogaster.

Males carrying a large deficiency in the long arm of the Y chromosome known to delete the fertility gene kl-2 are sterile and exhibit a complex phenotype: (1) First metaphase chromosomes are irregular in outline and appear sticky; (2) spermatids contain micronuclei; (3) the nebenkerns of the spermatids are nonuniform in size; (4) a high molecular weight protein ordinarily present in sperm is absent; and (5) crystals appear in the nucleus and cytoplasm of spermatocytes and spermatids. In such males that carry Ste+ on their X chromosome the crystals appear long and needle shaped; in Ste males the needles are much shorter and assemble into star-shaped aggregates. The large deficiency may be subdivided into two shorter component deficiencies. The more distal is male sterile and lacks the high molecular weight polypeptide; the more proximal is responsible for the remainder of the phenotype. Ste males carrying the more proximal component deficiency are sterile, but Ste+ males are fertile. Genetic studies of chromosome segregation in such males reveal that (1) both the sex chromosomes and the large autosomes undergo nondisjunction, (2) the fourth chromosomes disjoin regularly, (3) sex chromosome nondisjunction is more frequent in cells in which the second or third chromosomes nondisjoin than in cells in which autosomal disjunction is regular, (4) in doubly exceptional cells, the sex chromosomes tend to segregate to the opposite pole from the autosomes and (5) there is meiotic drive; i.e., reciprocal meiotic products are not recovered with equal frequencies, complements with fewer chromosomes being recovered more frequently than those with more chromosomes. The proximal component deficiency can itself be further subdivided into two smaller component deficiencies, both of which have nearly normal spermatogenic phenotypes as observed in the light microscope. Meiosis in Ste+ males carrying either of these small Y deficiencies is normal; Ste males, however, exhibit low levels of sex chromosome nondisjunction with either deficient Y. The meiotic phenotype is apparently sensitive to the amount of Y chromosome missing and to the Ste constitution of the X chromosome.

Animals↗

Effects of lysosomotropic weak bases on infection of BHK-21 cells by Sindbis virus.

The effects of the lysosomotropic weak bases chloroquine, ammonium chloride, and amantadine as well as dansylcadaverine (an inhibitor of receptor mediated endocytosis) on the replication of Sindbis virus in tissue-cultured cells was examined. Chloroquine had no effect on the expression of virus-induced homologous interference. None of these drugs significantly affected the ability of a complex of a cell and single virion to form an infectious center. Chloroquine and ammonium chloride were found to inhibit the synthesis of virus RNA in established infections when added early in infection. These drugs also inhibited the production of progeny virions when added any time after infection. These results suggest that the antiviral activity of these agents may not be due to an ability to prevent transport of the virus genome into the cell cytoplasm.

Amantadine↗

Urinary phenyl acetate: a diagnostic test for depression?

The compound 2-phenylethylamine is an "endogenous amphetamine" which may modulate central adrenergic functions. 2-Phenylethylamine is mainly metabolized by monoamine oxidase to form phenyl acetate (PAA). The 24-hour urinary excretion of PAA was measured in normal healthy volunteers and depressed patients. Patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, edition 3. In 70 percent of healthy volunteers of both sexes, the excretion of PAA ranged between 70 and 175 milligrams per 24 hours (mean = 141.1 +/- 10.2). Inpatients with major depressive disorder (unipolar type) (N = 31) excreted less PAA (68.7 +/- 7.0 milligrams per 24 hours) and 55 percent of them excreted less than 70 milligrams per 24 hours; there were no significant differences in the PAA excretion between untreated patients (N = 13) and those treated with antidepressants that were not effective (N = 18). The PAA excretion was reduced to a lesser extent in 35 less severely depressed unipolar outpatients (drug-free for 1 week) (86.3 +/- 11.8 milligrams per 24 hours). These results suggest that low PAA urinary excretion may be a reliable state marker for the diagnosis of some forms of unipolar major depressive disorders.

Adolescent↗

Polycaryocyte formation mediated by Sindbis virus glycoproteins.

The process of cell fusion mediated by Sindbis virus membrane proteins synthesized after infection was examined. At the times after infection at which virus proteins were detectable on the cell surface, Sindbis virus-infected BHK-21 cells were found to express a fusion function after brief treatment at acid pH. In studies employing wild-type virus and temperature-sensitive mutants and testing drug or protease inhibition of virus production, we made the following observations on Sindbis virus-mediated fusion from within. (i) Fusion requires the synthesis of virus glycoproteins and their transport to the cell surface. (ii) Modification of the cell plasma membrane by polypeptides PE2 and E1 alone is not sufficient for expression of the fusion function. (iii) The proteolytic conversion of plasma membrane-associated PE2 to E2 is not essential for fusion. (iv) Glycosylation of virus plasma membrane proteins is essential for fusion. (v) The lesions of Sindbis virus temperature-sensitive mutants do not affect their ability to fuse cells.

Animals↗