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Biomedical subjects

J Carter

Publications and source records attributed to J Carter.

At least 289 records · Page 16Linked to original sources

Comparative chronotropic activity of beta-adrenoceptive antagonists.

1. Chronotropic dose-response curves (non-cumulative) for beta-adrenoceptive antagonists were constructed from results in rats anaesthetized with pentobarbitone and depleted of catecholamines by pre-treatment with syrosingopine.2. Depletion of catecholamines lowered resting heart rate and reduced the threshold to the chronotropic action of isoprenaline by about 50%. Eight beta-adrenoceptive antagonists produced a dose-dependent chronotropic response but the maximum response was in all cases smaller than that obtained with isoprenaline. The order of activity was dichloroisoprenaline>LB 46>practolol>INPEA>oxprenolol>pronethalol>alprenolol>I.C.I. 45,763 (Kö 592). Propranolol and sotalol were without significant activity. The duration of the chronotropic response to the antagonists was more prolonged than that to isoprenaline. Propranolol caused a parallel shift to the right of the dose-response curves for the agonist effects of the antagonists.3. Estimation of beta-adrenoceptor blocking activity in anaesthetized cats gave an order of activity dissimilar to that found for maximum agonist responses: LB 46 > oxprenolol > alprenolol > propranolol > I.C.I. 45,763 > practolol > dichloroisoprenaline > sotalol > INPEA > pronethalol.4. Consideration of chemical structure and physico-chemical properties did not explain the differences between the agonist activities of the adrenoceptive antagonists.

Acetanilides↗

Recognition of superpotent sweetener ligands by a library of monoclonal antibodies.

Monoclonal antibodies (mAb) made to the superpotent guanidino sweet tasting ligand, N-(p-cyanophenyl)-N'-(diphenylmethyl)-guanidineacetic acid were examined for their molecular recognition specificities using 14 different sweetener analogues in a competitive radioimmunoassay. The effects of variations in pH on ligand binding was also examined by radioimmunoassay. Photoaffinity labelling of the binding site was accomplished using a radiolabelled azido-derivative of the parent ligand, and L-chain or H-chain labelling was easily identified in several different mAb. For two of the mAb examined in this study (NC6.8 and NC10.14), the analogue binding studies are in agreement with the known Fab-ligand crystal structures. Monoclonal antibodies to this family of sweet tasting compounds may be useful probes for the study of sweet taste chemistry and identification of novel sweet taste ligands from combinatorial chemical libraries.

Acetates↗

Seeking meaning and hope: self-reported spiritual and existential needs among an ethnically-diverse cancer patient population.

Spiritual beliefs and practices are believed to promote adjustment to cancer through their effect on existential concerns, including one's personal search for the meaning of life and death, and hope. This study sought to identify the nature, prevalence, and correlates of spiritual/existential needs among an ethnically-diverse, urban sample of cancer patients (n=248). Patients indicated wanting help with: overcoming my fears (51%), finding hope (42%), finding meaning in life (40%), finding spiritual resources (39%); or someone to talk to about: finding peace of mind (43%), the meaning of life (28%), and dying and death (25%). Patients (n=71) reporting five or more spiritual/existential needs were more likely to be of Hispanic (61%) or African-American (41%) ethnicity (vs. 25% White; p<0.001), more recently diagnosed (mean=25.6 vs. 43.7 months; p<0.02), and unmarried (49% vs. 34%; p<0.05), compared with those (n=123) reporting two or fewer needs. Treatment status, cancer site, education, gender, age, and religion were not associated with level of needs endorsement. Discriminant analysis found minority status to be the best predictor of high needs endorsement, providing 65% correct classification, p<0.001. Implications for the development and delivery of spiritual/existential interventions in a multi-ethnic oncology setting are discussed.

Adolescent↗

Disorders of cardiac conduction accompany the dive reflex in man.

The faces of 19 healthy subjects were immersed in water at the temperatures varying between 10 degrees and 30 degrees C and at different degrees of lung inflation. Several abnormalities of cardiac conduction were noted. They occurred with the greatest frequency in the coldest water and when there was relatively little air in the lungs at the moment of immersion. There was fragmentary evidence, confirmatory of earlier studies, that heart-rate slowing was accentuated by fear and that very little slowing occurred when the subject was distracted or preoccupied. Various conduction abnormalities were recorded. The most striking finding was the wide difference from person to person in the occurrence of conduction disturbances under more or less comparable circumstances. Moreover, the patterns of conduction alterations, differing from person to person, were nevertheless relatively consistent from dive to dive for the same individual. To ascertain whether or not such idiosyncratic responses may have prognostic significance calls for a long-term, prospective study.

Adult↗

Innovations in neonatal case management: an integrated, data-driven approach.

The intent of this article is to provide one company's perspective on the challenging and complex care management of the high-risk neonate. The strategies presented herein should enable and encourage case managers to implement an integrated management process for the frail neonatal population.

Case Management↗

The role of zinc in caspase activation and apoptotic cell death.

In addition to its diverse role in many physiological systems, zinc (Zn) has now been shown to be an important regulator of apoptosis. The purpose of this review is to integrate previously published knowledge on Zn and apoptosis with current attempts to elucidate the mechanisms of action of this biometal. This paper begins with an introduction to apoptosis and then briefly reviews the evidence relating Zn to apoptosis. The major focus of this review is the mechanistic actions of Zn and its candidate intracellular targets. In particular, we examine the cytoprotective functions of Zn which suppress major pathways leading to apoptosis, as well as the more direct influence of Zn on the apoptotic regulators, especially the caspase family of enzymes. These two mechanisms are closely related since a decline in intracellular Zn below a critical threshold level may not only trigger pathways leading to caspase activation but may also facilitate the process by which the caspases are activated. Studies by our laboratory in airway epithelial cells show that Zn is co-localized with the precursor form of caspase-3, mitochondria and microtubules, suggesting this Zn is critically placed to control apoptosis. Further understanding the different pools of Zn and how they interact with apoptotic pathways should have importance in human disease.

Animals↗

Analysis of clinicopathologic factors in malignant mixed Müllerian tumors of the uterine corpus.

The aim of this study was to retrospectively analyze the clinical and pathologic data of a series of patients presenting to our unit with uterine malignant mixed Müllerian tumors (MMMT) to attempt to identify prognostic factors and relate them to survival. Thirty-seven patients diagnosed with MMMT of the uterus from 1988 through 2000 were identified from the gynecological tumor registry. Data was abstracted and analyzed. The effect of a variety of clinical, histopathologic, and surgical variables on recurrence and survival were analyzed by univariate and multivariate analyses. Patients tended to be postmenopausal, overweight, hypertensive, and presented with abnormal bleeding. Preoperatively 28 (76%) were thought to have clinical stage I-II disease. Nine (32%) were upstaged based on surgical data. Five (56%) of these patients were found to have gross extrauterine disease and four (44%) were found subsequently to have microscopic extrauterine disease. Twenty (54%) patients underwent lymph node dissection and positive nodes were found in seven (35%) patients. Nine patients underwent omentectomy and disease was found in three (33%). Peritoneal washings were positive in three of 16 patients (19%). At the completion of primary surgery, 27 (75%) patients had no residual disease. Twelve (44%) of these patients had recurrence of disease. Median disease-free interval prior to first recurrence was 15 months. Median overall survival was 30 months. Log-rank analysis performed on multiple variables, including stage, age, residual disease, and depth of myometrial invasion showed a statistically significant association with overall survival probability. Only stage remained a significant independent variable predictive of overall survival (P = 0.034). We found that stage was an independent prognostic factor for overall survival in patients with uterine MMMT. Age, depth of myometrial invasion, and residual tumor were significant prognostic factors on univariate analysis. These factors may be a guide in order to select a group of high risk patients that may benefit from adjuvant therapy.

Aged↗

Cardiovascular and neuroendocrine responses to extended laboratory challenge.

The purpose of this study was to examine the effects of a 2-hour laboratory challenge on heart rate, blood pressure, catecholamines, and cortisol; and investigate the contribution of the physical act of speaking on both neuroendocrine and cardiovascular measures. Using a within-subjects design, 14 subjects were tested individually during two separate laboratory sessions. During one session, subjects engaged in two cognitively demanding tasks for 2 hours. During the other session, subjects executed the verbal demands of the tasks for 2 hours, but cognitive demands were absent. During both sessions, blood pressure and heart rate were measured and arterialized blood samples were obtained for the measurement of epinephrine, norepinephrine, and cortisol. Subjects demonstrated significantly greater increases in systolic blood pressure diastolic blood pressure, heart rate, epinephrine, and cortisol during the cognitively challenging session than during the control session. It is concluded that sustained elevations in cardiovascular and neuroendocrine measures can be achieved in the laboratory, and that the effects of such tasks cannot be attributed solely to the physical demands of speaking. Implications for the measurement of circulating catecholamines and cortisol during laboratory studies are discussed.

Adult↗

Parent's meetings in a hospital day centre.

This paper is an attempt to describe a project of parent meetings in a day centre for young handicapped children. It tries to reconcile social worker activity with sociological theory of disability and deviance and to weigh the relative balance of parent and professional contributions to care.

Child↗

Difficult clinical decisions in gynecological oncology: identifying priorities for future clinical research.

This study investigates the acceptability and feasibility of conducting randomized controlled trials (RCTs) in gynecological oncology by ascertaining the views of the Australian Society of Gynaecologic Oncologists (ASGO) about important clinical questions in this field, current treatment preferences, and willingness to participate in trials to address these questions. Members of ASGO received a mailed survey. Thirty-one gyneoncologists participated in this study (79% response fraction). There was considerable support for an RCT (81%; 95% confidence interval [CI], 63-93%) to compare sentinel node biopsy with total groin dissection for women with vulval cancer. This clinical question was also rated as "extremely" or "very" important by 91% (95% CI, 74-98%) of respondents, who also indicated high levels of individual equipoise. Another priority for research involved the use of second-line chemotherapy for women who have rising CA125 titers. This clinical question was rated as extremely or very important by 71% (95% CI, 52-86%), exhibited high levels of individual equipoise, with 74% (95% CI, 55-88%) of respondents willing to participate in an RCT to address this issue. The conduct of surveys of representative groups of clinicians provides useful empirical data to focus clinical research efforts where they are most likely to be successful based on equipoise, feasibility, and clinical interest.

Adult↗