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Biomedical subjects

D Carpenter

Publications and source records attributed to D Carpenter.

At least 55 records · Page 3Linked to original sources

Do large-scale remedial and dredging events have the potential to release significant amounts of semivolatile compounds to the atmosphere?

Laboratory studies suggest that substantial amounts of polychlorinated biphenyls are rapidly volatilized from wet contaminated solids during water evaporation. If significant losses also occur during field activities, potential analytical, global, and health implications should be considered in the design and monitoring of remedial actions and the handling of contaminated solids.

Air Pollutants↗

A new method of developing expert consensus practice guidelines.

To improve the quality of medical care while reducing costs, it is necessary to standardize best practice habits at the most crucial clinical decision points. Because many pertinent questions encountered in everyday practice are not well answered by the available research, expert consensus is a valuable bridge between clinical research and clinical practice. Previous methods of developing expert consensus have been limited by their relative lack of quantification, specificity, representativeness, and implementation. This article describes a new method of developing, documenting, and disseminating expert consensus guidelines that meets these concerns. This method has already been applied to four disorders in psychiatry and could be equally useful for other medical conditions. Leading clinical researchers studying a given disorder complete a survey soliciting their opinions on its most important disease management questions that are not covered well by definitive research. The survey response rates among the experts for the four different psychiatric disorders have each exceeded 85%. The views of the clinical researchers are validated by surveying separately a large group of practicing clinicians to ensure that the guideline recommendations are widely generalizable. All of the suggestions made in the guideline are derived from, and referenced to, the experts' survey responses using criteria that were established a priori for defining first-, second-, and third-line choices. Analysis of survey results suggests that this method of quantifying expert responses achieves a high level of reliability and reproducibility. This survey method is probably the best available means for standardizing practice for decisions points not well covered by research.

Bias↗

The Expert Consensus Guidelines for treating depression in bipolar disorder.

We present expert consensus guideline recommendations for the treatment of bipolar depression. These were arrived at through the statistical aggregation of the survey responses of 61 leading clinical researchers to eight questions about the key decision points in the management of bipolar depression. The experts' first-line recommendation for treating psychotic depression in bipolar disorder is to provide a combination of mood stabilizer, antidepressant, and neuroleptic medication. For severe, but nonpsychotic bipolar depression, the experts recommend the combination of a mood stabilizer and an antidepressant. For milder bipolar depression, a mood stabilizer and an antidepressant together or a mood stabilizer alone would be first line. The experts' antidepressant dose and dosing schedule recommendations are equivalent for unipolar and bipolar depression, but the experts recommend a faster discontinuation of antidepressants during the maintenance phase in bipolar patients--probably to reduce the risk of rapid cycling. Among the antidepressants, the experts prefer bupropion and the serotonin reuptake inhibitors as first line. They also believe that bupropion is least likely among antidepressants to cause switches to mania. Among mood stabilizers, the experts rate lithium as most likely to have a direct antidepressant effect.

Algorithms↗

The recognition of haemoglobin by antibodies raised for the immunoassay of beta-amyloid.

Canine and porcine cerebrospinal fluid (CSF) were fractionated by size exclusion chromatography and analysed by a luminescence enzyme linked immunosorbent assay (ELISA) configured to detect beta-amyloid. A peak of activity was observed in the CSF consistent with the molecular weight of beta-amyloid. When CSF contaminated with blood was analysed an additional peak of immunoreactivity at a higher molecular weight was observed. The peak of activity was found to be derived from cross-reactivity of the immunoglobulins employed in the ELISA with haemoglobin. These findings are discussed with reference to primary and structural sequence homology between beta-amyloid and haemoglobin from a number of species, the known properties of beta-amyloid and recent clinical reports.

Amyloid beta-Peptides↗

Isometric torso rotation strength: effect of training frequency on its development.

OBJECTIVE: To examine training frequency's effect on torso rotation muscle strength. DESIGN: The study followed a pretest-posttest randomized-group design. SETTING: University laboratory. PATIENTS: Subjects, 33 men (age 30 +/- 11yr) and 25 women (age 28 +/- 10yr) with no history of low back pain, volunteered to participate in the study and were tested for isometric (IM) torso rotation strength before (T1) and after (T2) 12 weeks of training. Measurements of maximal voluntary IM torso rotation torque (N.m) were made through a 108 degrees range of motion (54 degrees, 36 degrees, 18 degrees, 0 degree, -18 degrees, -36 degrees, -54 degrees). Subjects were stratified by peak torque at T1, and randomized to a nonexercising control group (C, n = 10), or groups that trained once a week (1x/wk, n = 16), twice a week (2x/wk, n = 17), or three times a week (3x/wk, n = 15); and all groups were similar in strength. INTERVENTIONS: Training consisted of 8 to 12 repetitions of full range dynamic variable resistance exercise to volitional fatigue, for both left and right rotation. MAIN OUTCOME: To determine the best training frequency for the development of torso rotation strength. RESULTS: Relative improvements (average increase in strength gained at each angle) for the training groups were 4.9%, 16.3%, and 11.9% for the 1, 2, and 3x/wk groups, respectively. The 1x/wk group did not increase in IM torso rotation strength compared to the control group at any angle. Both the 2 and 3x/ wk groups increased their IM torso rotation strength compared to the control group at all but one angle. There were no significant differences in IM torso rotation strength between the groups that trained 2 or 3x/wk. During the training period, the 2 and 3x/wk groups increased their dynamic training load significantly more than the 1x/wk group. CONCLUSIONS: Posttraining dynamic strength was not different between training frequencies of 2 and 3x/wk. Therefore, training the rotary torso muscles 2x/wk is recommended.

Adult↗

Variation in the determination of follicular diameter: an inter-unit pilot study using an ultrasonic phantom.

Ultrasound operators in assisted reproductive technology units in New South Wales, Australia cooperated in a study that was conducted to assess their ability to measure fixed objects embedded in an ultrasound phantom. The results have demonstrated a large variation ranging between 10 and 25% coefficient of variation on distances between 10 and 32 mm. As ultrasonic imaging is the only component of assisted reproductive technology not currently controlled by an external quality assurance scheme, the authors suggest there may be a need to establish a programme.

Female↗

Consensus methods in practice guideline development: a review and description of a new method.

Practice guidelines are an increasingly important means of conveying to practitioners and administrators the most appropriate methods of treating patients. Although the development of practice guidelines relies on scientific evidence, the consensus of expert opinion is an important ingredient, particularly in many key areas of clinical decision making that are insufficiently informed by experimental data. The authors review current methods in the assessment of expert opinion for practice guideline development and the problem of the lack of quantification. A new method is presented for quantification of expert opinion on surveys, and the development of expert consensus practice guidelines from the resulting data.

Clinical Medicine↗

Personality pathology among married adults with bipolar disorder.

The comorbidity of DSM-III-R axis II personality disorders in patients with bipolar disorder has received less attention than for unipolar depression perhaps because of the potential confounding of state vs. trait qualities. The current study took steps to separate pathological traits of personality from behaviors evidenced during discrete affective episodes in a sample of married, outpatient bipolar patients. Data indicated that 22% of our patients met criteria for a categorical diagnosis of personality disorder. Axis II pathology as represented by both categorical and dimensional scores was associated with increased psychiatric symptoms during subsequent treatment and poorer social adjustment.

Adult↗

Whole body movements in altered G environments.

Davies and Rennie determined that the instantaneous peak and mean power transferred to the center-of-mass of a subject during jumping could be calculated from analyzing the ground reaction force. Since Davies and Rennie's report, vertical jumping has been used to measure the peak and mean power transferred to the center-of-mass and to assess human performance. It has also been suggested that the external load a subject experiences effects the power production. However, it is difficult to determine if the difference in power production as defined in these studies is due to the external loading, or is an effect of changing the dynamics of the movement. In this paper, we describe a study which allows us to more clearly define the power developed during jumping under different weights, and the relationship between the power developed and jump height.

Adult↗

A conserved region in the tail domain of vimentin is involved in its assembly into intermediate filaments.

Although the head and rod domains of intermediate filament (IF) proteins are known to play significant roles in filament assembly, the role of the tail domain in this function is unclear and the available information supports contradictory conclusions. We examined this question by comparing transfection of the same cDNA constructs, encoding vimentins with modified tail domains, into cell lines that do and do not contain endogenous IF proteins. By this approach, we were able to distinguish between the ability of a mutant IF protein to initiate assembly de novo, from that of incorporating into existing filament networks. Vimentins with modifications at or near a highly conserved tripeptide, arg-asp-gly (RDG), of the tail domain incorporated into existing IF networks in vimentin-expressing (vim+) cells, but were assembly-incompetent in cells that did not express IF proteins (vim-). The failure of the RDG mutant vimentins to assemble into filament arrays in vim- cells was reversible by re-introducing a wild-type vimentin cDNA, whereupon both wild-type and mutant vimentins coassembled into one and the same IF network. We conclude that the function of the tail domain of type III IF proteins, and possibly of keratins K8 and K18, in IF assembly is distinct from those of other domains; a region encompassing the RDG tripeptide appears to be important in the assembly process.

Adrenal Gland Neoplasms↗

Protein and DNA elements involved in transactivation of the promoter of the bovine herpesvirus (BHV) 1 IE-1 transcription unit by the BHV alpha gene trans-inducing factor.

In herpes simplex virus (HSV)-infected cells, the transcription of immediate-early (alpha) genes is regulated by a virion component, the alpha gene trans-inducing factor (alpha TIF). This protein forms a complex with cellular factors and TAATGARAT motifs present in one or more copies in the promoters of all alpha genes. We have characterized the bovine herpesvirus 1 (BHV-1) homolog of this protein. Like its HSV counterpart, the BHV alpha TIF was synthesized in the later stages of infection and could be demonstrated to be a component of purified virions. In transient expression assays, BHV alpha TIF was a strong transactivator and stimulated the activity of IE-1, the major BHV-1 alpha gene promoter, with an efficiency comparable to that of HSV alpha TIF. This stimulation was largely dependent on a TAATGAGCT sequence present in a single copy in IE-1, and BHV alpha TIF, in conjunction with cellular factors, formed a complex with oligonucleotides containing this sequence. Despite these similarities between the two alpha TIFs, our preliminary observations suggest that the proteins may activate transcription by different mechanisms. Although BHV alpha TIF strongly transactivated IE-1, it differed from its HSV counterpart in that the carboxyl terminus of BHV alpha TIF, when fused to the DNA-binding domain of GAL4, was a relatively poor stimulator of a promoter containing GAL4-binding sites. Also unlike HSV alpha TIF, removal of the carboxyl terminus of BHV alpha TIF reduced but did not eliminate the ability of the protein to transactivate IE-1. These results are discussed in view of the structural similarities and differences among the alpha TIFs of alphaherpes-viruses.

Amino Acid Sequence↗

Acting up and physical illness: temporal patterns and emerging structure.

Many psychoanalytic writers have viewed acting out and somatization as alternate routes for the discharge of uncontained aggressive impulses in borderline patients. In order to investigate this empirically, we tracked the occurrence of two related behaviors--acting up and physical illness--over the course of one patient's long-term hospitalization. Daily scores on these variables were analyzed using a time series procedure. Results indicated that as treatment progressed, acting up and physical illness became more synchronized, and this occurred just prior to symptom remission. Material from psychotherapy suggested that these behavioral changes were associated with the patient's increased ability to verbalize aggressive impulses in the context of fantasy and memory.

Acting Out↗

Very low concentrations of acetylcholine and GABA modulate transmitter responses.

Acetylcholine and GABA, at extremely low concentrations (10(-14) to 10(-8) M) which do not induce electrical responses, each modulate the chloride-dependent responses of Aplysia neurons to higher concentrations of the same transmitters. Low concentrations of acetylcholine cause a reduction of the response to both acetylcholine and GABA, while low concentrations of GABA cause a facilitation of responses to both acetylcholine and GABA. These effects have a clear threshold, are slow in onset, reversible with prolonged washing, and blocked by cooling.

Acetylcholine↗

Biochemical and functional abnormalities in hypercholesterolemic rabbit platelets.

This study was designed to elucidate changes in rabbit platelet lipids induced by a cholesterol rich diet and to explore the possible correlation of these lipid changes with platelet abnormalities. Pronounced biochemical alterations were observed when serum cholesterol levels of 700-1000 mg% were reached. Hypercholesterolemic (HC) platelets contained 37% more neutral lipids and 16% less phospholipids than the controls. Lysolecithin, cholesterol esters and phosphatidylinositol (PI) levels were increased in HC platelets, and the levels of phosphatidylcholine (PC) were decreased. The cholesterol/phospholipid molar ratio of lipidemic platelets increased from 0.55 +/- 0.011 to 0.89 +/- 0.016 (P less than 0.01) in eight weeks. HC platelets had 90% more arachidonic acid (AA) in the PI than normal platelets. No significant changes in AA of PC were observed. Platelet function was monitored by the uptake and release of [14C]serotonin in platelet rich plasma (PRP), using varying concentrations of collagen as an aggregating agent. The uptake of [14C]serotonin in HC and normal platelets ranged from 78-94%. The percent of [14C]serotonin released from normal and HC platelets was proportional to the concentration of collagen. However, lipidemic platelets were hyperreactive to low concentrations of collagen. Incorporation of 50 microM acetylsalicylic acid into the aggregating medium suppressed the release of [14C]serotonin in normal PRP by more than 90%, but had only a partial effect on lipidemic PRP.

Animals↗

Modulation of HLA-DR expression in epithelial cells by interleukin 1 and estradiol-17 beta.

Both ultrapure human interleukin-1 (IL-1) and Escherichia coli derived recombinant IL-1 alpha and beta consistently induced the expression of major histocompatibility class II (HLA-DR) molecules in a human endometrial and a breast carcinoma cell line. [35S]Methionine incorporation into IL-1 induced, immunoprecipitable HLA-DR molecules demonstrated de novo synthesis of both light and heavy chains of the HLA-DR molecules. Lipopolysaccharide, recombinant interleukin-2 and recombinant interleukin-6 failed to induce HLA-DR expression in these epithelial cells. In contrast to the dramatic effect on HLA-DR expression, IL-1 had no effect on the epithelial cell proliferation. Pretreatment of T47D cells with estradiol-17 beta significantly decreased the IL-1 induced HLA-DR expression, and pretreatment of IL-1 with an IL-1 specific antibody, neutralized IL-1 action. These studies demonstrate that a cytokine (IL-1) and a sex steroid hormone estradiol-17 beta can interact to regulate the expression of HLA-DR molecules in epithelial cells.

Epithelium↗

The intracolonic bypass tube for left colon and rectal trauma. The avoidance of a colostomy.

Traumatic perforations of the left colon and rectum are most frequently managed by procedures that include the formation of a colostomy. Primary repair without colostomy is much less commonly employed. We report nine patients with traumatic perforations of the left colon and rectum treated with the intracolonic bypass tube (ICBT) without concomitant colostomy. In all these patients we believe the standard treatment would have included fecal diversion. Four patients sustained blunt trauma and five sustained penetrating trauma. Healing of the colonic anastomosis occurred in all cases, and the ICBTs were passed per rectum between the tenth and nineteenth days postoperatively. On the basis of this study, we conclude that the ICBT has a role in the treatment of selected injuries of the left colon and rectum as a safe means of avoiding a colostomy.

Adult↗