Search PubMed⌕ Search

Biomedical subjects

J Downey

Publications and source records attributed to J Downey.

At least 37 records · Page 2Linked to original sources
PubMed1993

Neurobiology and sexual orientation: current relationships.

Despite great progress in the neurosciences, our understanding of the determinants of sexual orientation is incomplete. The authors review for the clinician/neuropsychiatrist studies pertaining to the formation of sexual orientation in the following areas: hormone effects on sexual behavior (animal and human); the complicated relationship between gender identity, gender role, and sexual orientation in humans; cross-cultural studies of homosexuality; behavioral observations in pseudohermaphrodites and offspring of mothers treated with hormones during pregnancy; brain studies of homosexual and heterosexual individuals; and genetic studies. The authors conclude that human sexual orientation is complex and diversely experienced and that a biopsychosocial model best fits the current state of knowledge in the field.

Animals↗
PubMed1993

Psychoanalysis, psychobiology, and homosexuality.

The potential role of biological influences in human sexual orientation was considered more seriously during the early phases of psychoanalysis than in the years since World War II. Recently studies of homosexuality and heterosexuality in the neurosciences have attracted widespread attention both in the scientific and lay communities. The salience of these new data for psychoanalytic theory and practice is just beginning to be explored. In this article, we review research on sexual orientation in the following areas: genetics, crosscultural studies, studies of development in individuals with abnormal prenatal hormone exposure, childhood play patterns, and brain studies in both nonhumans and humans. Differences between male and female homosexuality are explored. We propose that psychoanalytic theory can grow and profit from a careful consideration of new findings in the psychobiology of sexuality, and that the interaction between mind and body is the appropriate purview of psychoanalysis.

Brain↗
PubMed1992

Welp et al. reply.

Explore the source record for details and available documents.

Journal Article↗
PubMed1992

Movement of pseudomonas aeruginosa along catheter surfaces. A mechanism in pathogenesis of catheter-associated infection.

The etiologic mechanism involved in the establishment of catheter-associated bacteriuria is suggested in this in vitro study of the movement of Pseudomonas aeruginosa along a catheter surface against a flowing artificial urine milieu in the presence and absence of antibiotics. Following a lag phase, during which a bacterial biofilm becomes firmly established at a site of contamination, the bacteria ascend the surface of the Foley catheters in a rapidly expanding coherent biofilm. The speed of the bacterial ascent is increased as a result of turbulence-associated planktonic saltatory bacterial movement within the urine column. Bacteriocidal concentrations of antibiotics in the urine can slow down the bacterial ascent, but they do not preclude it.

Catheterization↗
PubMed1992

The psychiatric status of women presenting for infertility evaluation.

Psychiatric symptomatology, incidence of clinical depression, measures of self-esteem, and sexual functioning were not found to be significantly different between a group of 118 women undergoing infertility evaluation and treatment and a demographically similar group of 83 routine-care women patients with no known fertility problems. However, a significant number of the infertility patients reported changes in mood and in sense of self-worth since becoming concerned about conception.

Adult↗
PubMed1992

Cyclooxygenase products are not involved in the protection against myocardial infarction afforded by preconditioning in rabbit. Cyclooxygenase pathway's involvement in preconditioning.

The mechanism whereby preconditioning with a transient period of ischemia renders the heart resistant to infarction from a subsequent ischemic insult is unknown. The purpose of this study was to determine whether cyclooxygenase pathways are involved in preconditioning's protection. Two inhibitors of that pathway, meclofenamate (MEC) and aspirin (ASP), were test in an in situ and a blood perfused isolated heart model, respectively. Preconditioning was achieved with 5 minute ischemia and 10 minutes reperfusion. All in situ hearts underwent 30 minute ischemia followed by 180 minute reperfusion, while the isolated hearts experienced 45 minute ischemia plus 120 minute reperfusion. Infarct size was measured with TTC stain. In the in situ model, 39.9% +/- 4.2% of the ischemic zone was infarcted in control hearts but only 8.8% +/- 2.2% in preconditioning hearts. Pretreatment with MEC (5 mg/Kg) caused no alteration of infarct size in either non preconditioned (34.3% +/- 8.3%) or preconditioned hearts (6.7% +/- 3.3%). In isolated hearts, 45 minute ischemia caused 31.0% +/- 5.9% of the ischemic zone to be infarcted in control hearts and only 5.4% +/- 2.2% in preconditioned hearts. Pretreatment with ASP (1 mg/Kg) failed to affect infarct size in either non preconditioned (35.7% +/- 3.7%) or preconditioned hearts (10.2% +/- 1.9%). The data indicate that cyclooxygenase pathways are not involved in the preconditioning's protection.

Analysis of Variance↗
PubMed1991

Pyrophosphate inhibition of Proteus mirabilis-induced struvite crystallization in vitro.

Struvite (MgNH4PO4.6H2O) crystals, the major mineral component of infectious urinary calculi, were produced in vitro by growth of a clinical isolate of Proteus mirabilis in artificial urine. P. mirabilis growth and urease-induced struvite production were monitored by phase contrast light microscopy and measurements of urease activity, pH, ammonia concentrations, turbidity, and culture viability. In the absence of pyrophosphate, struvite crystals appeared within 3-5 h due to the urease-induced elevation of pH and initially assumed a planar or 'X-shaped' crystal habit (morphology) characteristic of rapid growth. When pyrophosphate was present, initial precipitation and crystal appearance were significantly impaired and precipitates were largely amorphous. When crystals did appear (usually after 7 or 8 h) they were misshapen or octahedral in shape indicative of very slow growth. X-ray diffraction and Fourier transform infrared spectroscopy (FTIR) identified all crystals as struvite. Trace contaminates of carbonate-apatite (Ca10(PO4)6CO3) or newberyite (MgHPO4.H2O) were produced only in the absence of pyrophosphate. P. mirabilis viability and culture pH elevation were unaffected by the addition of pyrophosphate, whereas urease activity and ammonia concentrations were marginally reduced. Struvite could also be produced chemically by titration of the artificial urine with NH4OH. If pyrophosphate was present during titration, the same inhibitory effect on crystal growth occurred, so it is unlikely that urease inhibition is important. Lowering of pyrophosphate concentration from 13-0.45 mumol/l did not reduce its inhibitory activity so it is unlikely to act by chelating free Mg2+. We propose that pyrophosphate inhibits struvite growth principally through direct interference with the chemical mechanisms involved in crystal nucleation and growth, because of its effectiveness at very low concentrations.

Ammonia↗
PubMed1991

Cognitive ability and everyday functioning in women with Turner syndrome.

This paper presents results from an assessment of cognitive ability and everyday functioning in a group of adult women with Turner syndrome (TUS). Twenty-three TUS women were compared with 23 matched controls with constitutional short stature (CSS). A subgroup of 10 TUS women were compared with their nondisabled female siblings. On the Wechsler Adult Intelligence Test-Revised (Wechsler, 1981), no significant group differences were found in Verbal IQ. There were significant group differences for Performance IQ and Full Scale IQ, largely due to specific deficits in the area of spatial and mathematical ability. These difficulties were also evident on the Benton Visual Retention Test-Revised (Benton, 1974). TUS individuals had significantly lower educational attainment than CSS controls but did not differ from their siblings. TUS individuals had significantly lower occupational attainment than the women in both comparison groups.

Achievement↗