Search PubMed⌕ Search

Biomedical subjects

R Diamond

Publications and source records attributed to R Diamond.

At least 19 recordsLinked to original sources
PubMed1995

Apoptosis induced by serum deprivation of PC12 cells is not preceded by growth arrest and can occur at each phase of the cell cycle.

Previous studies have shown that PC12 cells undergo apoptosis (programmed cell death) when deprived of serum. In the present study, we examined the relationship of this death process to the cell cycle. PC12 cell populations synchronized at different, specific phases of the cell cycle exhibit similar kinetics of cell death following deprivation of serum. Flow cytometry analysis was used to examine the levels of apoptotic death in these cell populations in relationship to their progression in the cell cycle during the course of serum deprivation. Such analysis revealed that the cells die during the G0-G1, S, and perhaps G2-M phases and at the G2 to G1 transition. These results, therefore, suggest that the death of synchronized, serum-deprived PC12 cells occurs throughout the cell cycle and is not dependent on growth arrest. Flow cytometry methodology (acridine orange staining), which determines the RNA content of cells in relationship to their position in the cell cycle, was used to address these questions in nonsynchronized cells. These experiments revealed that, upon serum deprivation, an immediate loss of RNA occurred from cells in G1, S, and G2-M phases. This loss is accompanied by a slower appearance of cells with degraded DNA content. These results show that cells from all phases of the cell cycle are damaged upon serum deprivation and thus suggest that the apoptotic cell death of nonsynchronized PC12 cells may occur from each phase of the cell cycle.

Animals↗
PubMed1995

An infertility primer for family therapists: I. Medical, social, and psychological dimensions.

A seemingly "self-evident truth" in most people's lives is that one day they will have children. This universal, biopsychosocial assumption goes unchallenged until a couple faces infertility. Although the effects of such a challenge are profound, infertility is often treated as a nonevent--both within our society as a whole, and within the field of family therapy in particular. To assist clinicians who work with this numerically increasing population, and the many others who have been affected by their encounter with infertility in the past, this article discusses the biological/medical, psychological, and social factors that shape the experience of infertility in our society.

Adaptation, Psychological↗
PubMed1995

An infertility primer for family therapists: II. Working with couples who struggle with infertility.

The distress of infertility and its medical treatments are profound, and the effects reverberate in each partner, the couple dyad, and the couple's relationships with family, friends, and medical systems. Yet family therapists, like others in our society, are often uninformed or misinformed about the experience of infertility. While the legacies of infertility may be painful and enduring, they often remain unspoken, and hence may be overlooked in standard interviews. This article describes the experiences of couples struggling with infertility, most of whom have sought medical intervention, and it provides treatment interventions for guiding couples through this difficult and often uncharted terrain. Case vignettes derived from 2 years of this clinical research study are included.

Adaptation, Psychological↗
PubMed1993

A new patient focused index for measuring quality of life in persons with severe and persistent mental illness.

The quality of life in persons with severe and persistent mental illness is often poor. Most treatment programmes have the goal of increasing quality of life. Unfortunately, existing methods to assess quality of life are cumbersome and oriented towards research rather than clinical settings. This study describes preliminary steps in the development, testing and application of a new patient focused index for measuring quality of life in persons with severe mental illness. The Quality of Life Index for Mental Health (QLI-MH) differs from existing instruments in that it is based on an easy to use, self-administered questionnaire that assesses nine separate domains that together encompass quality of life. Each domain can be individually weighted depending on its relative importance to the patient. Different parts of the instrument solicit information from the patient, the primary clinician, and, when available, the family. The instrument and its scoring system address limitations of previous approaches to quality of life measurement.

Activities of Daily Living↗
PubMed1993

Residual cognitive deficits 50 years after lead poisoning during childhood.

The long term neurobehavioural consequences of childhood lead poisoning are not known. In this study adult subjects with a documented history of lead poisoning before age 4 and matched controls were examined with an abbreviated battery of neuropsychological tests including measures of attention, reasoning, memory, motor speed, and current mood. The subjects exposed to lead were inferior to controls on almost all of the cognitive tasks. This pattern of widespread deficits resembles that found in children evaluated at the time of acute exposure to lead rather than the more circumscribed pattern typically seen in adults exposed to lead. Despite having completed as many years of schooling as controls, the subjects exposed to lead were lower in lifetime occupational status. Within the exposed group, performance on the neuropsychological battery and occupational status were related, consistent with the presumed impact of limitations in neuropsychological functioning on everyday life. The results suggest that many subjects exposed to lead suffered acute encephalopathy in childhood which resolved into a chronic subclinical encephalopathy with associated cognitive dysfunction still evident in adulthood. These findings lend support to efforts to limit exposure to lead in childhood.

Cognition Disorders↗
PubMed1992

On the multiple simultaneous superposition of molecular structures by rigid body transformations.

A method of optimally superimposing n coordinate sets on each other by rigid body transformations, which minimizes the sum of all n (n - 1)/2 pairwise residuals, is presented. In the solution phase the work load is approximately linear on n, is independent of the size of the structures, is independent of their initial orientations, and terminates in one cycle if n = 2 of if the coordinate sets are exactly superposable, and otherwise takes a number of cycles dependent only on genuine shape differences. Enantiomorphism, if present, is detected, in which case the option exists to reverse or not to reverse the chirality of relevant coordinate sets. The method also offers a rational approach to the problem of multiple minima and has successfully identified four distinct minima in such a case. Source code, which is arranged to enable the study of the disposition of domains in multidomain structures, is available from the author.

Algorithms↗
PubMed1992

Evidence of presymptomatic cognitive decline in Huntington's disease.

Asymptomatic persons at risk for Huntington's disease (HD) (N = 28) were assessed with neuropsychological, psychiatric, and neurologic tests while undergoing genetic linkage studies to determine their probability of carrying the HD gene. Those participants who were subsequently identified as probable gene carriers did not differ on neurologic or psychiatric examination from those subsequently identified as probable noncarriers. Neuropsychological data are presented for a subset of participants free of other conditions (such as alcoholism) putting them at risk for cognitive deficits. Among these subjects, probable gene carriers were inferior to probable noncarriers on the neuropsychological battery as a whole and on several individual tests involving learning and memory. The results suggest the presence of cognitive decline prior to identifiable motor impairments in HD.

Adult↗
PubMed1992

Evaluation of new antifungal drugs for the treatment of systemic fungal infections. Infectious Diseases Society of America and the Food and Drug Administration.

These guidelines are applicable to all fungal pathogens that produce systemic infections in humans. Specific examples are provided whenever they might clarify special issues. Systemic fungal infections usually are divided into two broad categories: endemic systemic fungal diseases, which occur classically in healthy hosts, and opportunistic fungal diseases, which occur almost exclusively in patients with impaired host defenses. Both the increasing frequency of disseminated histoplasmosis and coccidioidomycosis in patients with AIDS and the occurrence of candidemia due to vascular-line infections have begun to blur this distinction. The fungi included in these guidelines are Histoplasma capsulatum, Coccidioides immitis, Blastomyces dermatitidis, Candida species, Cryptococcus neoformans, Aspergillus species, and Sporothrix schenckii. Diagnosis of infections caused by these fungi should be based on culture of infected body fluids or tissues whenever possible. Cryptococcal and coccidioidal meningitis are exceptions. Amphotericin B remains the standard comparative agent for most new agents. Further studies of the efficacy of new oral agents used alone or after a hospital course of amphotericin B are needed. The agents currently available are usually inadequate for eradication of fungal infections in patients with AIDS, who may need prolonged treatment. Final assessment for these patients may need to be classified as clinical cure with presumed microbiologic persistence.

Antifungal Agents↗
PubMed1992

The pharmacotherapy of depressive illness in adolescence: II. Effects of lithium augmentation in nonresponders to imipramine.

The antidepressant value of lithium augmentation was assessed in a 3-week open trial involving 24 adolescents who remained highly depressed after 6 weeks of treatment with imipramine hydrochloride. Two patients responded dramatically during the first week, with an additional eight patients showing partial improvement during the 3-week trial. The overall magnitude of improvement in depression ratings was significantly greater than in an historical control group of nonresponders who continued to receive imipramine monotherapy during their hospital treatment. Results suggest the potential use of this adjunctive strategy in some tricyclic resistant adolescent depressives, although it appears less efficacious overall in this age group than in adults.

Adolescent↗
PubMed1990

On the use of normal modes in thermal parameter refinement: theory and application to the bovine pancreatic trypsin inhibitor.

A method is presented whereby the amplitude coefficients of molecular normal modes of vibration are treated as independent variables in the treatment of thermal effects in X-ray diffraction, and applied to the bovine pancreatic trypsin inhibitor, form II (P2(1)2(1)2(1), a = 74.1, b = 23.4, c = 28.9 A). It is shown that the description of molecular motion furnished by 892 isotropic temperature factors may be largely reproduced using only 19 molecular thermal parameters from which anisotropic temperature factors may be synthesised for every atom. The method shows that motions and/or disorders external to each molecule are the largest single source of apparent motion, and that the internal motions are comparable to those predicted by Levitt, Sander & Stern.

Aprotinin↗
PubMed1986

Why faces are and are not special: an effect of expertise.

Recognition memory for faces is hampered much more by inverted presentation than is memory for any other material so far examined. The present study demonstrates that faces are not unique with regard to this vulnerability to inversion. The experiments also attempt to isolate the source of the inversion effect. In one experiment, use of stimuli (landscapes) in which spatial relations among elements are potentially important distinguishing features is shown not to guarantee a large inversion effect. Two additional experiments show that for dog experts sufficiently knowledgeable to individuate dogs of the same breed, memory for photographs of dogs of that breed is as disrupted by inversion as is face recognition. A final experiment indicates that the effect of orientation on memory for faces does not depend on inability to identify single features of these stimuli upside down. These experiments are consistent with the view that experts represent items in memory in terms of distinguishing features of a different kind than do novices. Speculations as to the type of feature used and neuropsychological and developmental implications of this accomplishment are offered.

Adult↗
PubMed1986

Treatment compliance in end-stage renal disease patients on dialysis.

This paper reviews the current knowledge concerning treatment compliance in patients with end-stage renal disease (ESRD). Adult hemodialysis patient noncompliance with the treatment regimen is very common. Objective and subjective measures of compliance, however, are often weakly correlated. In addition, the patients may be compliant with some aspects of the treatment regimen, but noncompliant with others. Unfortunately, no current model of predicting the degree of hemodialysis patient compliance is very accurate. In spite of this, behavioral approaches to increase regimen compliance do have at least short-term efficacy. There is a paucity of published data on compliance in adult peritoneal dialysis patients and an almost complete absence of systematic studies of compliance in children and adolescent dialysis patients. A multidimensional nosology of compliance behavior in ESRD patients is, therefore, proposed, as well as an approach to the diagnosis of noncompliance in ESRD patients and to possible interventions.

Adolescent↗
PubMed1985

Drugs and the quality of life: the patient's point of view.

Although research has established the effectiveness of antipsychotic drugs in treating schizophrenic patients, the issue of the quality of life of patients on longterm medication has not been as clearly determined. The patient's and clinician's understanding of this criterion, both objective and subjective, is discussed. Social functioning, acceptance of dose, compliance or lack of compliance, and the relative benefits of medication are factors that contribute to treatment goals. Case examples are presented to demonstrate these variables and their impact on the outcome of treatment with antipsychotic medication and on the patient's quality of life.

Adult↗