Search PubMed⌕ Search

Biomedical subjects

L Kennedy

Publications and source records attributed to L Kennedy.

At least 55 records · Page 3Linked to original sources

Noninvasive evaluation of the patient with a pleural effusion.

Pleural fluid formation is an indicator of a pathologic process that may be of primary pulmonary origin but also may be a reflection of disease in virtually any other organ system or a systemic disease. A thoracentesis should be performed on any patient in whom the cause of the effusion has not been established yet. The possible exception to this is an effusion thought to be secondary to uncomplicated congestive heart failure. The presumptive or definitive diagnosis can be established in 75% of patients by following patient history, physical examination, and pleural fluid analysis.

Diagnosis, Differential↗

Women in crisis.

Explore the source record for details and available documents.

Crisis Intervention↗

Clinicopathologic correlations of antiphospholipid antibodies. An autopsy study.

The clinicopathologic correlations of antiphospholipid antibodies (aPLs) have so far only been examined in case reports and highly selected series. This study assessed the incidence of aPLs in 156 consecutive, unselected autopsies and correlated the pathological findings with the clinical histories. Elevations of aPLs were found in 20.5% of the autopsy population, compared with 9.6% of age- and sex-matched controls and 2% of healthy normal subjects. There was a higher incidence of thromboembolic disease in patients with elevated aPL levels compared with those without, but the histology of thrombi was similar in both groups, with no evidence of vasculitis in the aPL-positive individuals. Patients with transient ischemic attacks and cardiac valve lesions had a high incidence of aPLs, as reported previously. Five cases that fit the designation of primary antiphospolipid antibody syndrome were noted. The study concludes that aPLs are relatively common in a hospital autopsy population and are commonly associated with thromboembolic events, that the thromboemboli are not associated with vasculitis, and that primary aPL syndrome is more common than generally appreciated.

Aged↗

Assessment of endocrine function after transsphenoidal surgery for Cushing's disease.

OBJECTIVE: We assessed the endocrine outcome after transsphenoidal surgery for Cushing's disease. DESIGN: Five-year (mean) follow-up (range 1 month-12 years) of patients undergoing transsphenoidal surgery for Cushing's disease between 1977 and 1990; review of case notes, current clinical and biochemical assessment including 24-hour urinary free cortisol. SETTING: Northern Ireland. SUBJECTS: Forty-one patients (33F: 8M); mean age at diagnosis 39.1 years (9-72 years). MAIN OUTCOME MEASURES: Measurements of early post-operative 0800 h serum cortisol and 24-hour urinary free cortisol at least 24 hours after withdrawal of oral hydrocortisone therapy. This was followed by low dose dexamethasone testing. Current 24-hour urinary free cortisol measurements. Retrospective definition of cure. RESULTS: Twenty-seven patients were either cured or improved by surgery, 14 were considered definite failures. Of 19 patients cured, eight had unmeasurable early post-operative 0800 h serum cortisol levels while of 15 tested, 13 had complete suppression with dexamethasone and two suppressed normally but to still measurable levels (39 and 60 nmol/l respectively). Seventeen patients in total have subsequently had bilateral adrenalectomy of whom two have developed Nelson's syndrome. Seven of the 41 patients were shown to have definite cyclical cortisol secretion first diagnosed post-operatively in three patients. Hormone deficiency included TSH (5), LH/FSH (1), cortisol (1) and ADH (temporary in 7, permanent in 1). In all, seven patients had some type of permanent hormonal deficiency post-operatively. CONCLUSIONS: Transsphenoidal surgery offers a worthwhile cure rate without the necessity of life-long endocrine therapy. Post-operative endocrine assessment must be rigorous so that early further management can be planned in the significant percentage of patients in whom cure is not achieved. Early complete suppression on low dose dexamethasone testing is very suggestive of cure but repeated and long-term monitoring of 24-hour urinary free cortisol is advisable.

Adenoma↗

Bilateral adrenalectomy: low mortality and morbidity in Cushing's disease.

OBJECTIVE: We assessed the current role of bilateral adrenalectomy in the overall management strategy of hypercortisolism. DESIGN: Retrospective review of case notes. PATIENTS: Twenty-six patients (20F/6M); mean age 46 years (range 15-70 years), median duration of follow-up 5.25 years (0.6-19.1 years) who had undergone bilateral adrenalectomy at the Royal Victoria Hospital since 1972. Eighteen had had prior transsphenoidal surgery which did not control the hypercortisolism. MEASUREMENTS: Morbidity, mortality, incidence of Nelson's syndrome. RESULTS: Surgery was performed through bilateral postero-lateral incisions (20 patients) or a long epigastric incision (six patients). The mean combined weight of the adrenals at surgery was 11.2 g. Twenty patients received subcutaneous heparin and 18 antibiotic prophylaxis peri and post-operatively. There was no operative mortality. Minor complications included one post-operative wound infection and a small pneumothorax requiring drainage. Major complications occurred in two other patients, both with pre-existing invasive pituitary tumours and considered at high risk because of age and general debility. One patient had a massive pulmonary embolus and the other a subphrenic abscess post-operatively. This latter patient, the only mortality, died from an unrelated cause three years post-operatively. Six patients have subsequently undergone pituitary surgery and three have received external pituitary irradiation therapy for expanding tumours. CONCLUSIONS: Bilateral adrenalectomy, in experienced hands, is a relatively safe and useful management option in patients with hypercortisolism. Growth of a pituitary adenoma post-operatively is now the most worrying complication.

Adolescent↗

Incidence of microvascular complications in type 1 diabetic subjects with limited joint mobility: a 10-year prospective study.

Previous cross-sectional studies have shown a significant correlation between limited joint mobility (LJM) and the microvascular complications of Type 1 diabetes, but whether LJM precedes and, therefore, may be regarded as an early marker for complications is unknown. Twenty-two Type 1 diabetic patients (10 male/12 female; diabetes duration at follow-up 20.1 +/- 1.3 (SEM) years) with LJM, and 22 subjects matched for age, sex, and duration of diabetes, without LJM were observed over a 10-year period. Both groups were free of retinopathy and negative for 'dipstick' proteinuria at baseline. After 10 years, of 22 patients with LJM, 10 had developed background and 3 proliferative retinopathy compared with 9 and 1 control subjects, respectively. Microalbuminuria (20 < or = albumin excretion rate < 200 micrograms min-1) was present in 3 and macroalbuminuria (albumin excretion rate > or = 200 micrograms min-1) in 2 of LJM patients compared with 6 and 1 control subjects, respectively. Ankle and toe vibration perception thresholds, HbA1, mean HbA1 (a mean of serial HbA1 measurements obtained during the 10-year follow-up period), and arterial blood pressure did not differ between the two groups (p > 0.05). At 10-year review, 9 of the control subjects had developed LJM of whom 4 had retinopathy and 4 microalbuminuria. Thus, while LJM may be another 'chronic complication' of diabetes, its presence does not appear to predict those at increased risk of developing microvascular complications.

Adolescent↗

Long-term glycemic control and neurological function in IDDM patients.

OBJECTIVE: To examine the relationship between sensory modalities of neurological function and antecedent glycemic control in IDDM patients. RESEARCH DESIGN AND METHODS: Examinations were conducted on 220 IDDM patients (age at onset < 25 yr, duration < 18 yr) for the presence or absence of the right or left ankle reflex and determination of vibration perception threshold at each medial malleolus and great toe using biothesiometry. These parameters were related to the concurrent HbA1 and to a mean of serial measurements (mean HbA1) over the previous 6 yr. RESULTS: Ankle reflexes were absent in 39 (right ankle) and 41 (left ankle) patients, respectively. Mean (right + left) ankle and toe VPTs were 8.7 +/- 3.6 and 6.3 +/- 4.2 (mean +/- SD) (arbitrary units), respectively. Both the mean and concurrent HbA1 were significantly different in patients with absent ankle reflexes (11.6 +/- 1.9 and 12.2 +/- 2.8%, respectively) compared with present ankle reflexes (10.3 +/- 1.7, 10.3 +/- 2.1%) (P < 0.0001). Similarly, a present ankle reflex was related to mean HbA1 arbitrarily divided into groups < 10, 10-12, > 12% (P = 0.0009). In contrast, mean ankle VPT (8.0 +/- 2.2, 8.8 +/- 3.1, and 10.3 +/- 6.2) and toe VPT (5.5 +/- 2.2, 6.1 +/- 2.9, and 8.5 +/- 8.2) did not increase significantly with poor glycemic control (P > 0.05). Age, right ankle reflex, retinopathy, 24-h urinary albumin excretion rate, and erect systolic blood pressure were the only independent variables predicting the toe VPT using linear regression analysis. CONCLUSIONS: These findings support a role for glycemic control in neurological dysfunction in IDDM patients, but also suggest that other unknown factors may be involved.

Adult↗

Cyclical Cushing's syndrome first diagnosed after pituitary surgery: a trap for the unwary.

Three patients were studied after transsphenoidal microsurgery for Cushing's disease because their symptoms and signs were slow to settle and/or because they had variable endocrine results. All were established as having cyclical Cushing's syndrome, first diagnosed post-operatively. This may be a much more common finding than previously realized and emphasizes the need for detailed and ongoing endocrinological investigation after transsphenoidal surgery for Cushing's disease.

Adult↗

Comparison of methods for the determination of unbound triiodothyronine in pregnancy.

OBJECTIVE: To study the changes in unbound T3 concentration in the first trimester of pregnancy. DESIGN: We measured serum unbound T3 concentration before and after termination of pregnancy. PATIENTS: Twenty-six clinically euthyroid women. MEASUREMENTS: We used one non-analogue assay (Sclavo) and three analogue assays (Amersham, Becton Dickinson and Diagnostic Products Corporation). RESULTS: Regression analysis did not show any significant agreement between the analogue and non-analogue assays. After termination of pregnancy, unbound T3 concentration as measured by Sclavo and Amersham assays did not change whereas unbound T3 concentration increased and decreased as measured by Becton Dickinson and Diagnostic Products assays respectively. Changes were not directly related to albumin or thyroid binding globulin. CONCLUSION: We believe unbound T3 concentrations as measured by the analogue assays used in this study are due to a balance of errors and cannot be used to determine true physiological changes in pregnancy.

Abortion, Induced↗

Growth hormone treatment of adults with growth hormone deficiency: results of a 13-month placebo controlled cross-over study.

OBJECTIVE: We aimed to study the effect of biosynthetic growth hormone (GH) replacement in growth hormone deficient adults. DESIGN: We performed a double-blind placebo-controlled cross-over study of 6 months biosynthetic GH, replacement and 6 months placebo separated by a 1-month's washout period. PATIENTS: Fourteen growth hormone deficient adults were studied. MEASUREMENTS: We measured total body weight, percentage fat mass, lean body mass, muscle volume, exercise capacity, maximum oxygen consumption, muscle strength, bone mineral content, a number of biochemical parameters, IGF-I, GH antibodies and psychological well-being. RESULTS: Total body weight remained unchanged, but lean body mass increased (before GH mean +/- SEM 49.8 +/- 5.5, after 53.4 +/- 5.6 kg; placebo before 51.2 +/- 5.4, after 50.4 +/- 5.1 kg; P less than 0.05 and fat mass decreased (before GH 21.5 +/- 4.1, after 19.3 +/- 4.3; placebo before 19.3 +/- 4.0, after 22.5 +/- 4.5 kg; P less than 0.05). Thigh muscle volume increased: (before GH 94.1 +/- 7.7, after 99.5 +/- 8.4 ml; placebo before 99.3 +/- 8.6, after 95.4 +/- 7.8 ml/0.8 mm computerized tomographic slice; P less than 0.05). Exercise capacity increased (before GH 174 +/- 15, after 199 +/- 18.9 watts; placebo before 162.5 +/- 2.3, after 154 +/- 19.8 watts; P less than 0.05), as did maximum oxygen consumption (before GH 1.93 +/- 0.2, after 2.17 +/- 0.2 l/m; placebo before 1.92 +/- 0.3, after 1.98 +/- 0.2 l/m; P less than 0.05). There was no change in quadriceps muscle strength. Alkaline phosphatase increased (before GH 87.5 (32-158), after 106.0 (49-179) U/I, placebo 99.5 (50-145), after 72.0 (40-111) U/I; P less than 0.05) without a change in the spinal bone density. IGF-I increased (before GH 62 (36-97), after 216 (62-362) micrograms/l; placebo before 59 (52-112), after 60.5 (38-94) micrograms/l; P less than 0.05). Carbohydrate tolerance remained unchanged as did fasting lipids, serum sodium, potassium, urea, calcium, phosphate and liver transaminases. Psychological well-being remained unchanged. No growth hormone antibodies were detected before or after GH treatment. CONCLUSIONS: GH alters the body composition of growth hormone deficient adults and leads to improved exercise capacity; alkaline phosphatase activity increases but without a change in spinal bone density, and carbohydrate tolerance remains unaltered.

Adult↗

T-cell receptor-gamma delta association with lymphocyte populations in sheep intestinal mucosa.

T cells expressing T-cell receptor (TcR)-gamma delta and CD8 represent a significant population in mouse and chicken intra-epithelial lymphocytes (IEL) but represent a minor population in human IEL. We examined the TcR-gamma delta usage and co-expression of CD5, CD4, CD8 and major histocompatibility complex (MHC) class II on isolated sheep IEL and lamina propria lymphocytes (LPL), and compared them with the TcR-gamma delta + cells in peripheral blood, intestinal lymph and jejunal Peyer's patches (PP). There were a number of notable differences. TcR-gamma delta + cells comprised 18% of IEL and 10% of LPL. Among the population of TcR-gamma delta + IEL, 24% were CD8+ and 54% were CD5+, which contrasts with the TcR-gamma delta + cells in blood and intestinal lymph that were universally CD5+ CD4- CD8-. A notable feature of the IEL was the presence of distinct CD8+ and TcR-gamma delta + populations that lacked CD5. Also a high percentage of IEL and LPL were CD2+ and MHC class II+. Analysis of the expression of MHC class II on T-cell subsets, as an indicator of activation, showed that 60-95% of the various IEL and LPL subsets were MHC class II+ compared with only 5-40% in jejunal PP, lymph nodes, spleen and blood. Therefore, it is possible that the circulating TcR-gamma delta + and CD8+ cells that localize in the gut epithelium might become activated and stop the expression of CD5 under the influence of the local microenvironment. These cells appear not to emigrate while still expressing the TcR-gamma delta + (CD8+) CD5- MHC class II+ phenotype. Our data, together with those from other studies, show that there is much heterogeneity in the use of TcR-gamma delta and accessory T-cell molecules by IEL.

Animals↗

The relationship between long-term glycaemic control and diabetic nephropathy.

Urine albumin excretion was studied by two widely accepted methods in 210 patients with insulin-dependent diabetes mellitus and related to the mean of serial glycosylated haemoglobin (HbA1) measurements made every 3 months during the previous 6 years. Microalbuminuria (albumin excretion rate > 20 micrograms/min) was present in 9.5 per cent of patients when defined by a 24-hour collection and 8.1 per cent of patients when defined by a timed overnight urine sample. Those with microalbuminuria, as estimated from a timed overnight urine sample, had a longer duration of diabetes but otherwise did not differ in age, duration of diabetes or arterial blood pressure from patients whose albumin excretion rate was 20 micrograms/min or less irrespective of the method of urine collection. The mean and the most recent HbA1 levels differed significantly between the normal and the microalbuminuric groups when defined by the 24-hour albumin excretion rate (p < 0.001, p < 0.01), but no significant difference between these groups was found when albumin excretion rates were calculated from the timed overnight urine sample. Albumin excretion rate, examined in relation to mean HbA1, increased significantly with worsening glycaemic control whether measured over 24 hours or overnight (p < 0.05, p < 0.01). These findings support an association between glycaemic control and microalbuminuria, but the correlation is weak, dependent on the method of urine collection and is just as good for a relatively short-term as for a long-term measure of average blood glucose.

Adolescent↗

Characterization of B-cell phenotypic changes during ileal and jejunal Peyer's patch development in sheep.

Changes in B-cell phenotype during development of ileal and jejunal Peyer's patches (PP) of sheep were investigated using flow cytometry and immunoperoxidase-stained cryosections. On Day 104 of gestation (term at 150 days) B-cell clusters were identified in the lamina propria of the ileum. These clusters were composed of cells that expressed surface IgM (sIgM), lambda or kappa light chain, and BAQ44A, a B-cell differentiation molecule. No cells in the clusters stained for terminal deoxynucleotide transferase. On Day 132 gestation, a change was evident in the phenotype of ileal PP B cells. Most B cells expressed a reduced level of sIgM and 20% were BAQ44A-. The B cells in the dome region were BAQ44A+ but few BAQ44A+ cells were present in the follicles. At 6-8 weeks of age BAQ44A+ cells were restricted to the dome region of the ileal PP; flow cytometric analysis confirmed that 25% of B cells isolated from the dome/follicle complex were BAQ44A+. Thus, the primordial PP was populated with B cells that were phenotypically similar to circulating B cells (sIgMhigh, BAQ44A+). After 132 days gestation, the predominant B-cell phenotype in the ileal PP changed to sIgMlow and BAQ44A-. This phenotypic change could be the result of either early immigrant B-cell differentiation or subsequent colonization by sIgMlow BAQ44A- B cells. The phenotypic changes of ileal PP follicular B cells were not complete until after birth and different phenotypic changes were observed in follicles of the jejunal PP of young lambs.

Animals↗

Ileal Peyer's patch emigrants are predominantly B cells and travel to all lymphoid tissues in sheep.

The ileal Peyer's patch (PP) was selectively labeled with fluorescein isothiocyanate by extracorporeal perfusion in 7-12 week-old lambs and the lymphocyte lineage and fate of the emigrants was determined by fluorescence microscopy and flow cytometry. PP emigrants were found in all tissues examined, accounting for 10%-15% of ileal mesenteric lymph node (MLN). 1%-2% of jejunal MLN, jejunal PP, prescapular lymph node (PLN) and 3%-4% of spleen cells. All ileal PP emigrants enter the ileal MLN on their way to the circulation. Removal of the MLN prior to perfusion enabled emigrants to go directly to the circulation and extravasate in distant tissues faster than in intact animals. The ileal MLN might provide an additional level of regulation for ileal PP emigrants. The perfused ileal PP contained about 25 times more B cells than T cells. The emigrant cells found in different tissues included both T and B cells but came to reflect, although to a lesser degree, the B cell composition of the tissue from which they were derived. One day after perfusion the composition of PP emigrants was similar to that of the tissue within which they were found; the spleen was the exception with a bias towards B cells. By day 3 the ratio of B to T cells in the PP emigrants was 1 for jejunal MLN and PLN. 1.5 for ileal MLN and jejunal PP, and 4-5 for the spleen and blood. It was concluded that the PP-derived T cells were recirculating T cells that were in the ileal PP at the time of perfusion. These cells emigrated rapidly and equilibrated such that they accounted for about 1.5% of the T cell pool in various tissues. Most PP-derived B cells were probably produced in the PP. The greatest contribution (24.4%) that ileal PP emigrants made to the B cell pool of a tissue was with the ileal MLN through which they are obliged to pass. The contribution was lower but still very significant in blood (8.9%), spleen (6.8%), PLN (3.9%), jejunal MLN (3.5%) and jejunal PP (1.8%). There was no evidence that ileal PP emigrants made a greater relative contribution to either T or B cell populations in MLN or jejunal PP than to non-gut-associated sites. The B cells were distributed throughout the immune system, which is in accordance with the proposal that the ileal PP is a site of primary B cell genesis in sheep.

Animals↗

A long-term dose-response study of somatostatin analogue (SMS 201-995, octreotide) in resistant acromegaly.

Ten acromegalic subjects were studied in a trial designed to ascertain the optimum dosage of the somatostatin analogue SMS 201-995 (octreotide) in active acromegaly. Twenty-four-hour growth hormone (GH) profiles were assessed monthly for 6 months and again after 1 year of continuous therapy. After basal assessment octreotide was administered subcutaneously at a dose of 100 micrograms three times a day throughout the first month. The dose was increased by 300 micrograms/day at monthly intervals to a maximum of 1500 micrograms/day, unless serum GH fell to within set criteria. Eight patients completed the trial. One patient withdrew because of intractable diarrhoea while another died of causes related to his acromegaly and we have no evidence that octreotide played any part in his death. Mean 24-h GH fell from a basal level of 34.3 +/- SEM 7.6 mU/l to 8.0 +/- 1.3 mU/l (P less than 0.05) after 6 months. At 1 month (300 micrograms/day) mean GH was 13.6 +/- 2.2 mU/l and at 2 months (600 micrograms/day) 10.8 +/- 2.2 mU/l (P less than 0.05 vs 300 micrograms/day dose), and at 5 months (1500 micrograms/day) 11.3 +/- 2.0 mU/l (all P less than 0.05 vs basal). Analysis of group means revealed no significant difference between any dose schedules above 600 micrograms/day. After 1 year the mean GH of the group (n = 8) was 7.5 +/- 1.3 mU/l (P less than 0.05 vs basal). Three patients developed a deterioration and one an improvement in their glucose tolerance and three developed asymptomatic gallstones during the year of therapy. In conclusion, octreotide lowered GH levels in acromegaly over a 1-year period. We found no evidence that routinely increasing the dose beyond 600 micrograms/day was helpful.

Acromegaly↗

Gene probe analysis in an informative family with multiple endocrine neoplasia syndrome type 2A (MEN 2A). Improvement in carrier risk estimation.

Gene probe analysis of the MEN 2A locus on chromosome 10 has been undertaken using the markers TB10.163, RBP 3 and TB14.34 in a large kindred with familial medullary thyroid carcinomas, with or without phaeochromocytomas or primary hyperparathyroidism. A maximum LOD score of 2.97 gave strong evidence of close linkage with zero recombination. For 12 members of the family so far not known to be affected by any form of the disease the estimated risk of carrying the gene has been considerably decreased in all but one, whose risk has been greatly increased.

Adolescent↗

Clinical, biochemical and immunoelectron microscopical evidence of dual hormone production in a mammosomatotroph cell adenoma.

This paper reports the occurrence of a rare, yet distinct pituitary adenoma which was surgically removed from a 42-year-old male with both clinical and biochemical evidence of acromegaly and mild hyperprolactinaemia. The monomorphic adenoma consisted of mature cells which were ultrastructurally indistinguishable from those of a prolactinoma. Electron immunocytochemistry, including a series of double-labelling techniques using selected colloidal gold particles as markers, indicated the presence of a pituitary adenoma in which the cells were capable of simultaneously producing growth hormone and prolactin and packaging them within the same secretory granule. This is thought to represent a mammosomatotroph cell adenoma.

Adenoma↗