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Biomedical subjects

A Heffernan

Publications and source records attributed to A Heffernan.

At least 19 recordsLinked to original sources
PubMed2006

Mitochondrial DNA sequence diversity in extant Irish horse populations and in ancient horses.

Equine mitochondrial DNA sequence variation was investigated in three indigenous Irish horse populations (Irish Draught Horse, Kerry Bog Pony and Connemara Pony) and, for context, in 69 other horse populations. There was no evidence of Irish Draught Horse or Connemara Pony sequence clustering, although the majority of Irish Draught Horse sequences (47%) were assigned to haplogroup D. Conversely, 31% of the Kerry Bog Pony sequences were assigned to the rare haplogroup E. In addition to the extant population analyses, ancient DNA sequences were generated from three out of four Irish archaeological specimens, all of which were assigned to haplogroup A.

Animals↗
PubMed2000

Airway complications in infants: comparison of laryngeal mask airway and the facemask-oral airway.

PURPOSE: To compare the incidence of airway complications in children less than one year of age whose airways were maintained during anesthesia with either a laryngeal mask airway (LMA) or a facemask and oral airway (FM-OA). METHODS: We randomized 49 - ASA class 1&2 - infants to an LMA or FM-OA group. All infants were undergoing minor general, urological or orthopedic procedures. Anesthesia was induced and maintained with halothane in nitrous oxide 50% and oxygen. The airway was removed in both groups when the infant was awake. The occurrence of airway complications (breath-holding, coughing, laryngospasm, secretions, obstruction and oxygen saturation < 95%) at induction of anesthesia, intraoperatively and during emergence from anesthesia was recorded. RESULTS: Airway complications occurred perioperaively in 15 of 27 infants in the LMA group and in 5 of 22 infants in the FM-OA group (P: 0.02). CONCLUSION: In infants, the use of the LMA is associated with an increased incidence of airway complications compared with the use of the FM-OA.

Airway Obstruction↗
PubMed1998

Sporting activity following kidney transplantation.

A postal questionnaire on sporting activity following renal transplantation revealed that most units encouraged participation in the majority of sports, but counselled against contact sports such as rugby football, boxing, and Asian martial arts.

Adolescent↗
PubMed1996

C-kit receptor (CD117) expression in acute leukemia.

The murine monoclonal antibody YB5.B8 (CD117) identifies a transmembrane tyrosine kinase receptor encoded by the human c-kit proto-oncogene. In this study we investigated the expression of c-kit on different types of acute leukemia to determine the degree of specificity and sensitivity of this marker for the myeloid and lymphoid lineages. C-kit was positive in over half of the 115 cases of acute leukemia studied. Overall, two thirds of AML cases expressed c-kit, whereas only one of 23 ALL patients was c-kit positive. C-kit was also positive in 16 of 19 cases of myeloid blast crisis of myeloproliferative disorders and negative in four with a lymphoid phenotype. There was no correlation between c-kit expression and the degree of myeloid differentiation by FAB subtypes or other markers. We conclude that c-kit is a specific marker for the myeloid lineage, which is expressed early during hematopoietic differentiation and can aid the diagnosis of AML in difficult cases. More patients need to be tested to establish whether the expression of c-kit may define AML subgroups of prognostic significance.

Acute Disease↗
PubMed1996

Aggressive thyroid cancer associated with toxic nodular goitre.

Reports of concurrent thyrotoxicosis and thyroid cancer have appeared in the last three decades. While most of the tumours have been clinically inconsequential, it has been suggested that thyroid carcinomas arising in patients with Graves' disease tend to behave aggressively, while those associated with toxic nodular goitre follow a more benign course. We report a contrary clinical experience with four cases of thyrotoxicosis associated with metastatic thyroid cancer, two of which were fatal. All four patients had toxic nodular goitre. Thyroid eye signs were uniformly absent. Two patients had received 131I therapy; none had other history of irradiation to the head or neck. Antimicrosomal and antithyroglobulin antibodies were absent in all four patients. Thyroid-simulating immunoglobulin, which was measured in one patient, was also absent. Histopathological examination of the resected thyroid glands revealed two papillary cancers. one mixed anaplastic/papillary and one anaplastic cancer. All four patients had cervical node involvement and one had pulmonary metastases. Both patients with anaplastic carcinoma succumbed to their disease within 6 months: neither of the patients with papillary cancer had disease recurrence after 2 and 4 years, respectively. The experience reported here of aggressive thyroid cancer associated with toxic nodular goitre may represent coincidence or, alternatively, it may represent the early recognition of a change in the natural history of toxic nodular goitre.

Adult↗
PubMed1994

A comparison of a modified form of Granuflex (Granuflex Extra Thin) and a conventional dressing in the management of lacerations, abrasions and minor operation wounds in an accident and emergency department.

A clinical study of 96 patients compared a new hydrocolloid dressing (Granuflex Extra Thin) with a non-adherent dressing (perforated film absorbent dressing) in the management of lacerations, abrasions and minor operation incisions at the Accident and Emergency (A&E) Department of the University College Hospital, Galway. While time to heal was similar for both groups, the patients using Granuflex Extra Thin experienced less pain (P < 0.001), required less analgesia (P = 0.0154) and were able to carry out their normal daily activities including bathing or showering without affecting the dressing or the wound. Patient satisfaction with the new dressing appeared to be very high especially in those patients who pursued an active lifestyle.

Adolescent↗
PubMed1991

Diagnosis under random conditions of all disorders of the renin-angiotensin-aldosterone axis, including primary hyperaldosteronism.

Theoretically, the relationship between plasma aldosterone (PA) and PRA in normal subjects under random conditions should differ from that in patients with primary hyperaldosteronism or primary adrenal failure, but should be similar to that in patients with secondary hyperaldosteronism or hyporeninemic hypoaldosteronism. PA, expressed as a function of PRA, the PA/PRA ratio, provides an index of adrenal sensitivity in normal subjects under routine conditions. The random PA/PRA ratios in patients with primary adrenal disorders did not overlap with those in normal subjects, patients with secondary adrenal disorders, hypertensive subjects, or other patients. A single elevated PA/PRA ratio, i.e. more than 920, associated with elevated PA in 4 patients or normal PA in 6 patients indicated primary hyperaldosteronism in 10 patients. However, 5 of 17 patients with chronic renal failure had elevated PA/PRA ratios, but did not have primary hyperaldosteronism. All 14 patients with secondary hyperaldosteronism had elevated PA associated with normal PA/PRA ratios. A single PA/PRA ratio of less than 28 associated with low PA in 18 patients and a normal PA in 1 patient indicated primary adrenal insufficiency, while a low PA associated with a normal PA/PRA ratio indicated hyporeninemic hypoaldosteronism in 7 patients. Fifty-nine patients with nonadrenal disorders other than renal failure had normal PA and PA/PRA ratios. Therefore, with the exception of patients with advanced renal failure, only a single blood sample is required to establish all diagnoses of disorders of the renin-angiotensin-aldosterone axis under random conditions.

Biomarkers↗
PubMed1988

Optimisation of total urinary aldosterone estimation: comparison with other laboratory methods for assessment of mineralocorticoid status.

We have demonstrated that conventional methods for measuring total urinary aldosterone (TUA) may markedly and inconsistently underestimate aldosterone output, since under the conditions usually employed (pH 1.0), the hydrolysis of aldosterone conjugates in urine is incomplete. The use of more acidic hydrolysis conditions (pH 0.2) overcomes this problem. However free aldosterone may be damaged at this pH. Therefore to accurately measure TUA output, it is necessary to isolate the undamaged aldosterone chromatographically and to correct for procedural losses based on the recovery of aldosterone tracer added to the urine prior to hydrolysis. We compared a number of laboratory estimates of aldosterone status (including urinary free aldosterone) with the 24-h urinary sodium output in normal subjects, since this provides a good bioassay of aldosterone. Sodium output correlated best with "optimised" 24 h TUA, i.e. hydrolysed at pH 0.2, (r = -0.589, P less than 0.001), and with plasma aldosterone (r = -0.504, P less than 0.005). Both aldosterone in random urine specimens and plasma renin activity correlated poorly with 24-h sodium output. Therefore, while the measurement of optimised TUA excretion provides the best index of aldosterone activity, assay of aldosterone in random specimens of plasma, which is more convenient for patient and laboratory, may be adequate for many clinical purposes.

Adult↗
PubMed1988

Sequential growth hormone deficiency and acromegaly.

This is the case of a patient with a pituitary tumour presenting initially with growth hormone deficiency and requiring treatment with human growth hormone. Eight years later he represented with acromegaly. This sequence of events has not to my knowledge been reported previously.

Acromegaly↗
PubMed1986

Evaluation of an aldosterone radioimmunoassay: the renin-angiotensin-aldosterone axis as a function of sex and age.

A highly specific radioimmunoassay for aldosterone in plasma has been developed utilising extraction from plasma into dichloromethane, an antiserum raised to aldosterone-3-carboxy-methyloxime-BSA and a radio-iodinated derivative of aldosterone. The plasma values obtained after only extraction correlated very well with the results following chromatography over celite. The within- and between-batch variations for plasma pools ranged between 5 and 15%. The range obtained, 100-1806 pmol/L for 96 random upright subjects, was comparable to others reported. Measurement of plasma aldosterone and plasma renin activity in these subjects showed that both these parameters are higher in subjects under 40 years of age than in those over 40. In addition, plasma aldosterone levels are higher in women than in men even though their plasma renin activity levels are similar. The plasma aldosterone/renin activity ratios which provide an index of adrenal sensitivity to stimulation, are lower in men than in women. The findings in this study suggest that higher aldosterone levels in younger subjects are associated with greater stimulation of the adrenals than in older subjects and that the adrenal is more sensitive in women than in men.

Age Factors↗
PubMed1971

A within-patient comparison of debrisoquine and methyldopa in hypertension.

In a titrated dose cross-over trial of debrisoquine and methyldopa in 38 hypertensive patients neither drug was superior in lowering supine or standing diastolic pressure with a minimum of side effects. Methyldopa caused significantly greater reduction of supine (P<0.001) and standing (P<0.02) systolic pressure but caused intolerable side effects in two patients. Tiredness was the most characteristic and troublesome side effect with methyldopa and postural hypotension was prominent in patients while on debrisoquine.

Adolescent↗