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D Sweeney

Publications and source records attributed to D Sweeney.

50 records · Page 3Linked to original sources
PubMed1983

Palmitate incorporation into different brain regions in the awake rat.

A quantitative method is presented to examine palmitate flux into a stable metabolic compartment in individual brain regions of awake rats. Following the i.v. injection of [14C]palmitate, brain radioactivity rose and then fell until, at 4 h, a stable concentration was reached that was maintained for up to 24 h. The flux of plasma palmitate into this 4 h compartment was calculated by dividing regional brain radioactivity at 4 h, as determined by quantitative autoradiography, by the integral of the plasma palmitate specific activity. Palmitate flux varied from 2.0 x 10(-5) mumol/g.s into the internal capsule to 9.3 x 10(-5) mumol/g.s into the arcuate nucleus, and generally was proportional to the regional cerebral metabolic rate for glucose, as measured with 2-deoxy-D-[1-14C]glucose. The results demonstrate that it is possible to determine unidirectional palmitate flux into a stable metabolic compartment in individual brain regions of awake rats, that flux into gray matter regions generally exceeds flux into white matter, and that palmitate flux is proportional to published values for regional brain oxidative metabolism.

Absorption↗
PubMed1983

Corneal edema accompanying aphakic extended lens wear.

Corneal swelling was monitored for nine hours in 14 unilateral aphakic patients who wore +13.25-diopter extended-wear lenses. After closed-eye wear, the corneal swelling was 6.9% and 11.4% for aphakic and phakic eyes, respectively. To determine if aphakic corneal swelling could be predicted from either corneal epithelial oxygen uptake or hypoxic corneal swelling, we measured epithelial oxygen uptake and corneal swelling from hypoxia. These were 3.67 mm Hg/s and 3.96 mm Hg/s and 8.0% and 12.1% for the aphakic and phakic eyes, respectively. Differences in these measurements between aphakic and phakic eyes were significant, but correlations of oxygen uptake rate and hypoxic swelling response to extended-wear edema were modest. A high intrasubject correlation between the edema accompanying extended-wear was found indicating that postsurgical extended-wear corneal edema may be predicted by measuring presurgical extended-wear corneal edema.

Adult↗
PubMed1983

The use of high-dose human menopausal gonadotropin in an in vitro fertilization program.

Sixty-three normal ovulatory women suffering from obstructive tubal disease not corrected by previous surgery were enrolled in an in vitro fertilization (IVF) program. To achieve a large number of mature follicles, a relatively high dose of human menopausal gonadotropin (hMG) was administered (19 +/- 4 ampules/cycle). Monitoring consisted of daily follicular ultrasonography and serum estradiol measurements. Human chorionic gonadotropin (10,000 IU) was administered when more than two large follicles (1.6 to 1.8 cm in diameter) were visualized. Fifty-five laparoscopies for oocyte retrieval were performed. A mean of 4.3 follicles per woman were aspirated, and 3.2 oocytes per woman were recovered. The oocytes were preincubated for 8 or 24 hours according to the morphologic degree of mucification and dispersal of the oocyte-corona-cumulus complex. Seventy-seven percent of the oocytes were fertilized and were transferred into the uterus 38 to 40 hours after insemination. Fifty-two women received one to eight embryos (mean, 3.5 +/- 1.9), and 9 (17%) conceived. This regimen of high-dose hMG precludes the need for serum or urine luteinizing hormone monitoring, because the occurrence of spontaneous ovulation is low. It is valuable in increasing the number of fertilizable oocytes, the percentage of women undergoing embryo transfer, and compensates with multiple oocyte transfer for the high embryonic loss involved in IVF.

Adult↗
PubMed1982

Effect of extracellular polysaccharides on diffusion of NaF and [14C]-sucrose in human dental plaque and in sediments of the bacterium Streptococcus sanguis 804 (NCTC 10904).

It has been postulated that extracellular polysaccharides form a barrier to diffusion in dental plaque. Diffusion coefficients, D, were measured for NaF and [14C]-sucrose in glucan-free and glucan-containing sediments of Strep. sanguis 804 at 37 degrees C. There was a tendency for NaF and [14C]-sucrose to diffuse faster as the carbohydrate concentration in the sediments increased. NaF diffused only 38 per cent more slowly in cell-free glucan sediment than in water, suggesting that glucan per se does not form a barrier to diffusion. The diffusion coefficient for NaF was positively correlated with carbohydrate concentration in individual plaque samples from 15 subjects and incubation of 3 plaque samples with sucrose resulted in both an increase in carbohydrate concentration in the plaque and an increase in D for NaF. Thus the presence of extracellular polysaccharides in plaque leads to slightly faster rates of diffusion. Nevertheless, the total time for diffusion through plaque may be increased if the presence of extracellular polysaccharides results in thicker layers of plaque.

Adult↗
PubMed1982

Antimanic, antidepressant, and antipanic effects of opiates: clinical, neuroanatomical, and biochemical evidence.

These clinical data may offer some support for the hypothesis that opiates have antidepressant, antimanic, and antipanic effects. This hypothesis should be studied directly by double-blind studies of the effects of exogenous and synthetic endogenous opioid peptides in patients with major depressive illness, panic and anxiety states, schizophrenia, and schizo-affective illness. These clinical data support our studies in nonhuman primates and man which suggest a common LC or NE hyperactivity may underly both drug withdrawal and spontaneous panic states. Whether endorphin deficiency or derangements account for the postulated NE hyperactivity needs additional study and we will discuss our preliminary work later. Failure of endorphins to terminate bursts in LC firing rate and NE release may be responsible for both of these types of panic states. In addicts, this mechanism could exist prior to opiate use, or abuse of potent exogenous endorphinomentic compound may cause an endorphin-abnormality. Both of these possibilities would be compensated by continuous opiate maintenance. Methadone maintenance is a complicated psychiatric, psychological, and social phenomenon. Further studies are necessary to evaluate the role of opiate maintenance in treating or suppressing the emergence of underlying psychopathology. Previous psychiatric hospitalization or treatment for a schizophrenic or affective illness may contraindicate absolutely the use of clonidine or other rapid detoxification methods. These data suggest the possibility of substituting a nonaddicting psychotropic medication for opiates in some patients who are self-medicators. The clinical data support other data suggesting the potential antipsychotic, antidepressant, and antianxiety/antipanic effects of the endogenous opioids, endorphins, and exogenous opioids, endorphins, and exogenous opiates. These and other data suggest potential utility for opioid agonists and endorphin testing in psychiatric treatment and diagnosis.

Adult↗
PubMed1978

Use of value clarification methods in venereal disease education.

The use of values clarification methods offers a means of dealing with the social-emotional stigmas associated with venereal diseass. It has become apparent that the facts alone are not sufficient in motivating the individual to seek treatment and cooperate in the epidemiologic process. This article suggests techniques of educating students or patients in order to get them in touch with their own feelings, attitudes, and prejudices. It also fosters understanding of the prevalent social myths and misconceptions about venereal diseases.

Attitude↗