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E Walters

Publications and source records attributed to E Walters.

At least 37 records · Page 2Linked to original sources
PubMed1994

Depression and parental bonding: cause, consequence, or genetic covariance?

It is shown how information on the direction of causation between variables may be obtained from a cross-sectional study of pairs of relatives. This method is applied to the study of the relationship between ratings of parents' rearing style and depression in their offspring. Adult female twins ascertained from a population-based registry in Viroffia completed the Center for Epidemiological Studies--Depression Scale (CESD) and a 7-item short form of the Parental Bonding Instrument (PBI) about each of their parents. Two dimensions of parental behavior, overprotectiveness and coldness, were analyzed jointly with depression data in both genetic factor and directional genetic models. Models that specify ratings of parents as a cause of depression in the offspring fit the data significantly better than models that specify depression as a cause of ratings of parents. A still better fit is obtained with models that specify common genetic variance to depression and ratings, though causal models with error variance perform almost as well. In general, ratings of fathers show more genetic and less shared environmental variance than ratings of mothers, which might arise from more consistent treatment of offspring by mothers than by fathers. No effect of children eliciting parental rearing style was detected with these data. The relative merits of instrumental variable, longitudinal, and family approaches to testing causal models are discussed.

Adult↗
PubMed1993

Olfactory cytochrome P-450 immunoreactivity in mice is altered by dichlobenil but preserved by metyrapone.

Antibodies to cytochromes P-450NMa and P-450NMb (CYP2A and CYP2G1, respectively) (P-450 nomenclature by Nebert et al., DNA Cell Biol. 10, 1- (1-14) 14, 1991) were used to assess the effects of the herbicide dichlobenil on the distribution of these olfactory-specific isozymes in the olfactory mucosa. Twenty-eight hours after a single dose (12 mg/kg) of dichlobenil, characteristic regions of the olfactory mucosa showed signs of necrosis in H&E stained sections. Accompanying this was a dramatic reduction in P-450 immunoreactivity in Bowman's glands of the olfactory mucosa, and an apparent redistribution of P-450 immunoreactivity within sustentacular cells. Treatment of mice with metyrapone, a P-450 inhibitor, at 10 min prior to and 2, 4, 6, and 8 h after a single dichlobenil injection, provided some protection against the damaging effects of dichlobenil. Both the gross and subcellular appearance of P-450 immunoreactivity in metyrapone/dichlobenil treated mice was similar to controls. Western blot analysis of P-450 expression following dichlobenil or metyrapone/dichlobenil treatment was generally consistent with immunohistochemical findings. These studies support previous reports that dichlobenil-induced olfactotoxicity is cytochrome P-450 mediated.

Animals↗
PubMed1992

Receptor neuron losses result in decreased cytochrome P-450 immunoreactivity in associated non-neuronal cells of mouse olfactory mucosa.

Immunohistochemical and immunoblot analyses were used to investigate nasal cytochrome P-450 distribution in mice with either unilateral naris closure for 3, 4, or 5 months, or olfactory bulbectomy. P-450 immunoreactivity was observed only in the supporting cells and Bowman's glands of the olfactory mucosa. Immunoreactivity was clearly reduced in rostral regions of the open-side olfactory mucosa where losses of receptor neurons resulted from 3 to 5 months of closure. Closed-side immunoreactivity was similar to controls. In 4 month closure animals that had regrown their receptor neurons, open-side immunoreactivity was comparable to controls. Olfactory bulbectomy also depressed P-450 immunoreactivity. These data suggest that presence or absence of receptor neurons markedly affects P-450 expression in nonneuronal cells of the olfactory mucosa.

Animals↗
PubMed1992

The sensitivity of Drosophila larvae to continuous-wave ultrasound.

The threshold for killing of freshly hatched Drosophila larvae exposed to continuous-wave (CW) ultrasound shows a minimum at approximately 0.3 MHz. This suggests that the stiffness of the material surrounding the gas bodies in the organism is comparable to water. From this, it is apparent that the gas bodies in three-day-old larvae that we have used in earlier studies are far larger than resonance size at the frequencies (1-5 MHz) used. Yet, these larvae were killed by short exposures to low-temporal-average-intensity pulsed ultrasound with peak intensities of the order of 10 W/cm2. Hence, it appears that "large" bubbles cannot be ignored in considerations of the biological effects of pulsed ultrasound and lithotripsy.

Animals↗
PubMed1991

Pleural effusion: an "acoustic window" for sonography of pleural metastases.

We report the sonographic findings in 32 patients with malignant disease associated with pleural effusions diagnosed by chest roentgenograms. No tumor lesions were seen in any case on X-ray films. Thoracic sonography, however, detected previously undocumented metastatic disease with diaphragmatic (N = 19), parietal (N = 8), visceral (N = 2) or combined (N = 3) pleural involvement. Additionally, a distinction could be made between nodular lesions (N = 19), sheet-like tumor masses (N = 10), and combined (N = 3) tumor spread. In all cases thoracentesis was performed. Cytology showed malignant cells in 28 patients. Pleural metastasis was histologically confirmed by ultrasound-guided fine needle biopsy in 2 cases. The present study demonstrates the value of scrutinized thoracic sonography in patients with pleural effusion for the detection of pleural metastases.

Adult↗
PubMed1991

A practicum in clinical nutrition as the internship component of an integrated masters/internship program.

In September 1990, Chedoke McMaster Hospitals (CMH) admitted two students to the Practicum in Clinical Nutrition. This program was developed at CMH in affiliation with the graduate programs in nutrition offered at McMaster University and the University of Guelph. This is the first program in Canada to integrate a graduate nutrition degree at the Master's level with a clinical nutrition training program. The purpose of this paper is to describe the need, goals, educational philosophy, developmental process and anticipated benefits of this practicum.

Curriculum↗
PubMed1988

Binding studies of three water-soluble polycationic porphyrins with human serum albumin.

The binding stoichiometry and equilibria of three polycationic water-soluble porphyrins with human serum albumin (HSA) have been determined by fluorescence quenching and filtration methods in 0.1M phosphate buffer, pH 7.2 at 25 degrees. For one porphyrin the binding equilibrium was also measured by measuring the lifetime of tryptophan and also by measuring the polarization of bound porphyrin. Energy transfer between the porphyrin and the tryptophan residue of HSA has been studied.

Humans↗
PubMed1985

Implantation, abortion, and birth after in vitro fertilization using the natural menstrual cycle or follicular stimulation with clomiphene citrate and human menopausal gonadotropin.

The incidence of pregnancy and abortion was analyzed in 1679 patients having embryos replaced after oocyte recovery and in vitro fertilization in order to alleviate their infertility. In these patients, 364 pregnancies were achieved and 108 abortions occurred. Patients were treated either on their natural cycle, having a spontaneous luteinizing hormone (LH) surge to induce ovulation, or after ovarian stimulation using clomiphene citrate alone or in combination with human menopausal gonadotropin (hMG). The data were assessed in relation to the numbers of embryos replaced, the follicular stimulation and ovulation induction regime used, the dose of gonadotropins and the dose of antiestrogens, and the age of the patient. The most successful treatment for the number of live births per laparoscopy was the use of clomiphene citrate in combination with human menopausal gonadotropin followed by human chorionic gonadotropin (hCG) to induce follicular maturation and ovulation. This treatment produced a significantly higher (P less than 0.001) number of patients with multiple embryos (86.5%). There was no significant effect on pregnancy or abortion with a low (less than 400-mg) or high (greater than or equal to 400-mg) dose of clomiphene. The total dose of gonadotropins used did not influence the incidence of pregnancy or abortion. The use of hCG with hMG induced a significant (P less than 0.01) positive effect on the incidence of pregnancy. The incidence of pregnancy showed a progressive decline with increasing age but there was a highly significant (P less than 0.01) increase in the incidence of abortion with increasing age. With increasing numbers of embryos replaced, up to three, the incidence of deliveries increased.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Spontaneous↗
PubMed1985

The influence of transient hyperprolactinemia on in vitro fertilization in humans.

Hormonal stimulants of ovarian follicular maturation and anesthesia/surgery were examined for their effects on the concentration of plasma and follicular fluid PRL. Forty-seven patients undergoing in vitro fertilization for the treatment of infertility were selected at random for this prospective study. Patients given human menopausal gonadotropin and clomiphene citrate had significantly higher levels of plasma PRL compared to those given clomiphene only. Anesthesia/surgery elevated plasma PRL levels in all patients, by as much as 50-fold and to as high as 7878 mIU/liter. Follicular fluid PRL levels were correlated with preanesthetic plasma PRL concentrations, but the latter were not correlated with plasma 17 beta-estradiol. Elevated plasma or follicular fluid PRL concentrations had no effect on in vitro fertilization of oocytes or embryonic development. Although not significant, the incidence of pregnancy was highest in the group of patients with the lowest preanesthetic plasma PRL levels.

Anesthesia↗
PubMed1984

A fatal case of creosote poisoning.

A case of fatal creosote poisoning is described. On presentation, extensive oropharyngeal ulceration was noted and gastric lavage withheld. Post-mortem examination showed an intact oesophagus and stomach.

Aged↗