Search PubMed⌕ Search

Biomedical subjects

D Friedman

Publications and source records attributed to D Friedman.

At least 199 records · Page 11Linked to original sources
PubMed1986

[Automated determination of total nitrogen in urine and feces].

Urine and stool total nitrogen was measured using the Carlo Erba Strumentazione NA 1500 nitrogen analyzer. Determinations were carried out on 10 mcl, 20 mcl and 50 mcl urine samples and on 20-50 mg stool samples. Both urine and stool data distributions were normal, thus indicating the reliability of the method. The NA and the classic Kjeldahl method gave very close results in the same urine specimen; slight and not significant differences were found in stool analysis, most likely caused by the poor homogeneity of the material. Due to the automation, they very short analysis time, the accuracy and the reproducibility of the results, NA 1500 can be used in clinical practice for nitrogen balance studies by direct measurement of losses.

Automation↗
PubMed1986

Informed consent in the difficult patient.

In an effort to determine how and why we have arrived at such a sophisticated level of confusion in regard to the medicolegal ramifications of informed consent, the author provides a brief review of the evolution of the principle of informed consent as well as workable guidelines for avoiding potential problems.

Forms and Records Control↗
PubMed1986

Event-related potentials in children at risk for schizophrenia during two versions of the continuous performance test.

Event-related potentials (ERPs) were recorded from children of schizophrenic parents, children of parents with affective disorders, and children of parents without a history of psychiatric illness. ERPs were elicited during two versions of the continuous performance test (CPT), which differed in their level of processing complexity. The data were recorded from electrodes located at midline frontal, central, parietal, and occipital scalp sites. Diagnostic assessments of the parents were performed using the Schedule for Affective Disorders and Schizophrenia-Lifetime Version and Research Diagnostic Criteria. Clinical assessments of the children were made with a modified version of the Global Assessment Scale. ERP amplitudes for six electrophysiological events were compared among groups for target and nontarget stimuli using analyses of variance of both factor score and baseline to peak measures. There was one isolated between-group finding: frontal negative slow wave recorded at FZ was of greater magnitude in the high risk (HR) than in either the psychiatric (PC) or normal control (NC) groups. Since only a small percentage of children at risk will eventually develop schizophrenia, ERP amplitude deviance and frequency distribution analyses were also performed and compared among groups. ERP component amplitudes did not distinguish the groups when each component was considered separately. Deviance analyses, using a combination of the amplitudes of the six ERP components, also did not provide evidence of a deviant subgroup within any of the three groups. There appeared to be no relationship between ERP component amplitudes and behavioral adjustment in adolescence. Some evidence of a relationship between deviant attentional functioning and ERP component amplitude was found, but the pattern of findings within the attentionally deviant HR subgroup was opposite to that found for the HR group as a whole and more consistent with the pattern found for the NC group.

Adolescent↗
PubMed1986

Pharmacological evaluation of an injectable prolonged release emulsion of physostigmine in rabbits.

Physostigmine was incorporated in an injectable emulsion in an attempt to prolong its pharmacological activity. Emulsions which remained stable over 6 month storage were prepared using optimal experimental conditions. The in-vitro kinetic examination revealed that the rate-determining step in the release process of physostigmine from the emulsion was its partitioning from the oily phase to the external aqueous phase. The in-vivo results indicated that the physostigmine emulsion was able to inhibit the cholinesterase activity for only 1 to 2 h. The preliminary pharmacokinetic analysis showed that the physostigmine emulsion apparently increased the bioavailability compared with the conventional injectable solution. This could be attributed either to the protection of the sensitive drug from the enzymatic degradation or to improved absorption. The presence of poloxamer micelles in the aqueous phase was shown to enhance the bioavailability of physostigmine without having any effect on its pharmacological activity or duration.

Acetylcholinesterase↗
PubMed1986

The prevalence of periodontitis and dental caries in a Down's syndrome population.

The prevalence rates of periodontitis and dental caries in 30 Down's syndrome patients and 30 matched, otherwise retarded, controls were compared. The populations were older than those usually studied, with mean (+/- SE) ages of 27.4 (+/- 2.1) and 28.9 (+/- 2.3) for the Down's syndrome and control groups, respectively. Bone loss was found in 60.0% of sites in the Down's syndrome patients, compared with 9.3% sites in controls. In Down's syndrome, bone loss was first seen at about age 16, with 92% of patients 16 or older having loss; in contrast, only 42% of control patients 16 or older had bone loss, which first appeared at about age 28. There was a considerable difference in caries prevalence in the two groups, with the Down's syndrome patients having a lower overall prevalence which was most noticeable with respect to interproximal lesions. Seven Down's syndrome patients over age 15 were caries-free, as opposed to only one control patient.

Adolescent↗
PubMed1985

[Evaluation of body composition in obese subjects].

The body composition of 12 obese patients was assessed. The dilution method was used to assess the total areas of sodium and water. Total potassium was measured indirectly using the following formula: total potassium = R X total body water-total body sodium, where R represents the contents in a whole blood sample. Both fat and muscle mass were found to be increased in the obese subjects. Examination of the total sodium/total water ratio and the relationship between weight and muscle mass, cellular mass and total fat showed the dimensional increase was harmonious.

Adipose Tissue↗
PubMed1985

Role of the anterior hypothalamus-preoptic area in the regulation of courtship behavior in the male Canadian red-sided garter snake (Thamnophis sirtalis parietalis): intracranial implantation experiments.

Testosterone (T) was administered intracranially to intact adult male Canadian red-sided garter snakes (Thamnophis sirtalis parietalis) in the fall and in the summer. Implants in the anterior hypothalamus-preoptic area (AH-POA) as well as other regions of the brain, including the medial and basal hypothalamus, thalamus, medial cortex, and third ventricle, failed to elicit courtship behavior. The spermatogenic stage was more advanced, and the circulating level of androgens was significantly higher, in animals that received implants of T in the AH-POA. These findings suggest the sex steroid-concentrating sites in the AH-POA of the garter snake are involved in feedback regulation of pituitary gonadotropin secretion and not in the control of courtship behavior. Hematocrit was found to be higher in animals that received implants of T, regardless of location, a response that may be related to changes in blood chemistry prior to hibernation. These findings support previous research indicating that in the adult male red-sided garter snake, a species exhibiting a dissociated reproductive tactic, courtship behavior is independent of testicular androgens.

Androgens↗
PubMed1985

Electrodermal recovery data on children of schizophrenic parents.

Half-amplitude recovery of electodermal responses is compared in children of schizophrenic parents (high-risk subjects) and children of depressed or normal parents. The results are dissimilar to those reported by Mednick and colleagues on a Danish high-risk sample. No significant differences emerged among the three groups in our study. Recovery did not differ according to sex or severity of illness of the schizophrenic parent. Recoveries of high-risk subjects separated from their homes were not shorter than recoveries of subjects who remained home. Recovery time recorded in childhood was unrelated to global adjustment in adolescence.

Adolescent↗
PubMed1985

Role of the anterior hypothalamus-preoptic area in the regulation of courtship behavior in the male Canadian red-sided garter snake (Thamnophis sirtalis parietalis): lesion experiments.

Lesions of the medial preoptic area and/or the ventromedial hypothalamus resulted in an abrupt and immediate decline in courtship behavior in adult male Canadian red-sided garter snakes (Thamnophis sirtalis parietalis). Lesions of the more anterior portions of the preoptic area resulted in a more gradual, delayed decline in courtship behavior. Male snakes sustaining lesions dorsal, ventral, or caudal to the anterior hypothalamus-preoptic area exhibited no change in courtship behavior relative to controls. Measurements of testis size, spermatogenic stage, and circulation levels of androgens revealed no differences between any of the groups. There were marked differences in the change in hematocrit over time between the groups. These results indicate that the anterior hypothalamus-preoptic area is involved in the control of courtship behavior in the adult male red-sided garter snake. Moreover, it is suggested that the stimulus affecting the anterior hypothalamus-preoptic area to activate courtship is temperature related.

Androgens↗
PubMed1985

Effect of estradiol and steroid analogues on the clearance of immunoglobulin G-coated erythrocytes.

Although the disproportionate frequency of several immunologic disorders among women is well recognized, the effect of sex steroids on immunologic processes is unclear. We used an animal model, which has helped to elucidate the effect of corticosteroids in vivo, to quantitatively assess the effect of estradiol and steroid analogues on the immune clearance of IgG-coated erythrocytes. While corticosteroids impaired the clearance of IgG-coated erythrocytes, estradiol, in doses comparable to those achieved during pregnancy, significantly enhanced the clearance. Estradiol, however, did not enhance the splenic clearance of heat-altered erythrocytes. Splenic macrophages isolated from estradiol-treated animals expressed enhanced receptor affinity for the Fc portion of immunoglobulin G [Fc(IgG)], an effect probably responsible for the enhanced in vivo clearance. No consistent effect of estradiol on the splenic macrophage C3 receptors was observed. The synthetic androgen danazol, the mineralocorticoid deoxycorticosterone, and the cortisol metabolite tetrahydrocortisone did not alter the clearance of IgG-coated cells after 7 d of therapy. The estrogen antagonist/agonist tamoxifen enhanced the clearance of IgG-coated cells, but to a lesser extent than estradiol. An effect of estrogens on macrophage Fc (IgG) receptor-mediated clearance may explain in part the variation in clinical expression of several autoimmune disorders during changes in hormonal state, such as pregnancy.

Anemia, Hemolytic, Autoimmune↗
PubMed1985

Initial experience with Hemasite vascular access device for maintenance haemodialysis.

Thirteen uraemic patients having undergone chronic haemodialysis from a minimum of 16 months to a maximum of 15 years (mean 6.5 years) with unsuitable peripheral vessels for standard arteriovenous fistulae, received Hemasite, a new vascular access device which provides vascular access without needle puncture. Eight devices are still being used routinely with enthusiastic acceptance by the patients. Three subjects died because of unrelated causes, two of whom had a functioning device. Nine thromboses occurred in five patients. Thrombectomy was successful in three subjects. There were two cases of infection with loss of one device. In conclusion, the main advantage of Hemasite is the possibility of performing haemodialysis without needles, thus potentially maintaining the longevity of graft fistula. The only disadvantage of the device is its cost.

Adult↗
PubMed1985

In vivo evaluation of immunological status after biliopancreatic bypass for obesity.

Cell mediated immunity was evaluated in vivo by means of the Multitest system in subjects at least one year after biliopancreatic bypass. Quantitative delayed hypersensitivity values were not significantly different between control, obese and partial biliopancreatic bypass subjects, while they were significantly (P less than 0.001) reduced in subjects who had total biliopancreatic bypass. The results demonstrate that cell-mediated immunity is not affected by partial biliopancreatic bypass, but that on the contrary, a severe immunosuppression follows total biliopancreatic bypass. A positive correlation between serum albumin concentration and Multitest score was found in all the operated patients.

Adult↗