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Biomedical subjects

J Noble

Publications and source records attributed to J Noble.

At least 91 records · Page 5Linked to original sources
PubMed1993

Glucocorticoid exposure in utero: new model for adult hypertension.

Hypertension is strongly predicted by the combination of low birthweight and a large placenta. This association could be due to increased fetal exposure to maternal glucocorticoids. Fetal protection is normally effected by placental 11 beta-hydroxysteroid dehydrogenase (11 beta-OHSD), which converts physiological glucocorticoids to inactive products. We found that rat placental 11 beta-OHSD activity correlated positively with term fetal weight and negatively with placental weight. Offspring of rats treated during pregnancy with dexamethasone (which is not metabolised by 11 beta-OHSD) had lower birthweights and higher blood pressure when adult than did offspring of control rats. Increased fetal glucocorticoid exposure secondary to attenuated placental 11 beta-OHSD activity may link low birthweight and high placental weight with hypertension.

Animals↗
PubMed1993

Tricyclic antidepressants in red cells and plasma: correlation with impaired intraventricular conduction in acute overdose.

OBJECTIVE: Tricyclic antidepressant levels in red blood cells and plasma in acute overdose and their association with cardiotoxicity were studied. METHODS: This was a prospective study in 15 patients with acute tricyclic antidepressant overdose. Tricyclic antidepressant parent compounds and metabolites were measured in red blood cells and plasma, and tricyclic antidepressant levels were correlated with ECG indexes of toxicity. RESULTS: Plasma levels of the parent compounds were higher than their red blood cell levels on admission (mean +/- SD, 691 +/- 409 and 337 +/- 220 ng/ml, respectively). Admission metabolite levels were higher in red blood cells than in plasma (264 +/- 180 and 190 +/- 164 ng/ml, respectively). QRS duration and the red blood cell levels of the metabolites were significantly correlated at the time of admission (r = 0.77, p < 0.01), as well as at 6 to 10 hours (r = 0.74, p < 0.01). CONCLUSIONS: In acute overdose, a shift of tricyclic antidepressants from plasma to red blood cells and increased levels of red blood cell metabolites reflect tissue redistribution of the drug. Tricyclic antidepressant red blood cell metabolites are the best markers for impaired intraventricular conduction.

Adolescent↗
PubMed1993

Comparison of propofol with enflurane during hypotensive anaesthesia for middle ear surgery.

Forty patients undergoing middle ear surgery were allocated randomly to receive propofol induction and maintenance, or thiopentone induction and enflurane maintenance for anaesthesia. Both groups also received fentanyl, alcuronium, nitrous oxide and oxygen. If this did not reduce systolic arterial pressure to 70 mm Hg, labetalol, glyceryl trinitrate (GTN), or both, was administered. Fifteen control patients had enflurane anaesthesia without hypotension. Pre- and postoperative psychometric tests were performed in all groups. The propofol group received significantly more labetalol (P = 0.014) and GTN (P = 0.004) than the enflurane group. There was a greater increase in reaction times after operation in the study groups (P < 0.05) compared with controls. There was no difference between the propofol and enflurane groups in control of arterial pressure, recovery from anaesthesia or psychometric testing.

Adolescent↗
PubMed1993

Choices of training programs and career paths by women in internal medicine.

PURPOSE: To examine the choices of career paths of women in internal medicine, specifically to determine (1) whether women continue to prefer primary care practice more often than men do and (2) whether differences in career paths between men and women result from differences in the natures of the training programs they complete. METHOD: A database containing demographic, training, and clinical-practice information on 19,151 physicians (3,569 women and 15,582 men) who had been trained in internal medicine was constructed by merging data from the National Resident Matching Program matches in internal medicine for 1977-1982 with data from the 1985 American Medical Association Physician Masterfile, which contains physician practice profiles. RESULTS: Similar percentages of the men and the women chose primary care residencies (8% versus 9%, ns) and trained in the 100 major medical centers (49% versus 50%, ns). The women more frequently trained in programs affiliated with medical schools in the top prestige quartile (38% versus 33%, p < .05). The attrition rates of residents who left their training for careers in other medical fields were the same for the men and the women (14%). Fewer women obtained board certification (74% versus 80%, p < .01). The women chose to practice general internal medicine more frequently than did the men (52% versus 45%, p < .0001), regardless of the training program completed (primary care or traditional). CONCLUSION: The women pursued primary-care-oriented internal medicine to a significantly greater degree than did the men, regardless of the type of training program completed (primary care or traditional).

Career Choice↗
PubMed1993

Cognitive function during moderate hypoxaemia.

The effect of hypoxaemia (mean SpO2 78%) on cognitive function was measured in two groups of twelve normal subjects. A series of psychometric tests was administered to each subject in the same sequence and consisted of the Reitan trail-making test, a digit symbol substitution test, a visuospatial orientation test and the simple unprepared reaction-time test. Psychomotor performance was assessed in a double-blind manner while the subjects were breathing first air and then either air or a hypoxic mixture. While there was improvement in time for the trail-making test during a repeat study breathing air, there was significant deterioration of time to completion of the test in conditions of hypoxia. A significant learning effect in the orientation test was seen in the control group but this did not occur in hypoxic subjects. Hypoxaemia was shown to cause a significant impairment of simple unprepared reaction time compared with controls. All the changes in cognitive function were small and there were no subjective differences in the air or hypoxic groups. The usefulness of the Reitan trail-making and the simple unprepared reaction-time test in the assessment of psychomotor performance deficit under conditions of hypoxaemia has been demonstrated by this study in normal subjects. It was concluded that a mean oxygen saturation of 78% caused only minor changes in cognitive function in normal subjects.

Adult↗
PubMed1993

Avoidable complications of arthroscopic surgery.

The incidence of complications from arthroscopic surgery is low. Between 1978 and 1991, 8500 arthroscopies were performed by the two senior authors (J.N. and D.R.A.D.). Several significant complications were recorded, and these are presented to show how they occurred, and how our practice of arthroscopy was subsequently modified. There were four cases of clinically detectable deep vein thrombosis of which three were associated with pulmonary embolus, three cases of haemarthrosis, two deep infections, three compartment syndromes with one case of impending compartment syndrome, six cases of instrument failure and one case of persistent synovial fistula.

Adult↗
PubMed1992

General internal medicine in internal medicine: at the core or on the periphery?

In the past decade, faculty in sections of general internal medicine have assumed responsibility for training residents, for staffing clinical practices, and for developing new domains of health services and effectiveness research. These activities form the core of internal medicine: They are integral to the role of internal medicine as an academic and patient care discipline, and they complement the activities of the internal medicine subspecialties. The effect of general internal medicine on internal medicine, therefore, has been to shift the focus away from the subspecialty services--which compartmentalize a patient's medical problems--and back to the concept of the patient as a "whole" person. The role and territory of the general internist are changing as a result of this shift in focus, and general internal medicine is emerging as the new core discipline in internal medicine. These changes have allowed for an expanded capacity of internal medicine to provide new services, modified curricula, and innovative research.

Holistic Health↗
PubMed1992

Career differences between primary care and traditional trainees in internal medicine and pediatrics.

OBJECTIVE: To assess the relation of Primary Care Residency Training to career choice, board certification, and practice location of internists and pediatricians. DESIGN: Cohort study with up to 8 years of follow-up. SETTING: The United States. PARTICIPANTS: The 17,933 residents trained in all internal medicine (13,750) and pediatrics (4,183) residency programs between 1977 and 1982 were studied using information from the National Resident Matching Program, the AMA Physician Masterfile, the Area Resource File, and a telephone survey. MEASUREMENTS: Career choice, board certification, and practice location were studied in relation to five explanatory variables: type of residency (primary care or traditional track), gender, year of medical school graduation, educational orientation of the teaching hospital, and medical school prestige. MAIN RESULTS: Graduates of primary care residency training programs chose careers in generalist primary care significantly more often than did graduates of traditional tracks in both internal medicine (72% compared with 54%) and pediatrics (88% and 81%, respectively; P less than 0.001 for both values). Board certification rates in internal medicine were statistically higher for graduates of primary care training programs (80%) than for graduates of traditional programs (76%, P = 0.002) but were not statistically significant for both groups of pediatric graduates. Graduates of primary care programs in pediatrics and internal medicine practiced in medically less served communities more often than did graduates of traditional programs. CONCLUSION: Graduates of primary care residency training programs in internal medicine and pediatrics differ from graduates of traditional residency programs in career choices, board certification rates, and practice locations.

Career Choice↗
PubMed1992

Use of motor nerve conduction testing and vibration sensitivity testing as screening tools for carpal tunnel syndrome in industry.

Increased attention to carpal tunnel syndrome in industry has resulted in the development of several proposed screening tests. This investigation evaluated the use of two portable devices for measuring motor nerve conduction time and tactile sensitivity to 120 Hz vibration in a field setting. Forty-seven control participants, 63 manufacturing plant workers with and without symptoms of carpal tunnel syndrome, and 22 patients with physician-diagnosed carpal tunnel syndrome were tested with the NervePace electroneurometer and the Vibration II vibration threshold measurement device. Nerve conduction time differed significantly between the controls, the asymptomatic workers, and the participants with carpal tunnel syndrome or symptoms of carpal tunnel syndrome. The vibration threshold was higher in the carpal tunnel syndrome group than in the other groups; however, further examination of the data revealed no differences in threshold unless nerve conduction time exceeded the control mean by at least three standard deviations. The false-negative rates associated with the tests limit their usefulness in screening for carpal tunnel syndrome.

Carpal Tunnel Syndrome↗
PubMed1992

The mechanical strength of various suture techniques.

The mechanical strengths of five techniques of tendon repair have been evaluated using human cadaver tendons. A modified Kessler repair with a peripheral circumferential suture and the method of Becker were found to require the greatest load to produce gapping, but the Becker and Savage repairs withstood the highest load before failure.

Humans↗
PubMed1992

Dupuytren's and epilepsy revisited.

The incidence of Dupuytren's disease amongst the residents of two epileptic centres was found to be 12.0% in one and 38.1% in the other. The overall incidence at the second was significantly higher than a control population (16.0%) and this difference was particularly apparent in patients over 50 years old. The distribution of the Dupuytren's disease was found to be very similar to that of non-epileptic patients. At both centres, the disease process was more severe, with an increased incidence of contractures. Drug therapy was not clearly implicated in the aetiology of this condition.

Adult↗
PubMed1992

The diagnostic potential of synovial effusion in meniscal pathology.

During a 20-month period, 382 arthroscopies were performed and the type of washout fluid obtained was noted. When a torn meniscus was found, the fluid was macroscopically abnormal in 97.4% of cases. A crystal clear washout was associated with no demonstrable pathology in over half the cases, the remainder having mainly patellofemoral joint pathology and other articular lesions. Only 6.3% of those with a clear fluid washout had meniscal pathology. Of those with abnormal fluid, 68% had meniscal pathology, with a normal arthroscopic examination being found in only 8.5%. In addition, when the fluid from traumatic effusions was examined microscopically, a typical droplet containing lipid crystals was found to be present and to account for an oily macroscopic appearance. These data support the use of fluid irrigation of the knee as a screening test for intraarticular pathology, especially of the menisci, that may allow a reduction in the number of negative arthroscopies.

Adolescent↗
PubMed1992

The role of an adhesive (Histoacryl) in tendon repair.

Two in vitro experiments have been done comparing various techniques of tendon repair. These include repairs using an adhesive, 2-butyl cyanoacrylate (Histoacryl), and repairs by the modified Kessler technique, using 4/0 braided polyester and 4/0 stainless steel. Mechanical analysis has shown that by replacing the circumferential suture of a modified Kessler tendon repair with Histoacryl, the tensile strength of the repair and the force needed to produce a gap can be increased by 30% to 40%. This improvement was statistically significant (P < 0.05).

Enbucrilate↗