Search PubMed⌕ Search

Biomedical subjects

D Mulcahy

Publications and source records attributed to D Mulcahy.

At least 91 records · Page 5Linked to original sources
PubMed1988

Detection of valvar obstruction by intracardiac masses using Doppler echocardiography.

The purpose of this paper was to examine valvar involvement in patients with intracardiac masses. Seven patients with intracardiac masses were studied by cross-sectional and Doppler echocardiography. In one, a candida vegetation on a mitral Starr-Edwards prosthesis obstructed the aortic valve with a peak transvalvar velocity of 2 m/sec and aortic regurgitation. Another patient with endocarditis demonstrated mitral stenosis as did two patients with left atrial myxomata. Tricuspid stenosis was demonstrated in three patients with right ventricular intracardiac masses (primary and secondary tumour and thrombus). By Doppler, the mitral and tricuspid stenosis was similar to from that seen in rheumatic heart disease with increased peak transvalvar velocity and prolonged pressure half-time. Because of the hazards associated with cardiac catheterisation in intracardiac masses, we conclude that Doppler ultrasound allows for the adequate assessment of the haemodynamic alterations so as to complement the images obtained by cross-sectional echocardiography.

Adult↗
PubMed1988

Labetalol in the treatment of stable exertional angina pectoris: a comparison with nifedipine.

Labetalol, a combined alpha- and beta-receptor antagonist, was compared with nifedipine in a placebo-controlled, randomized double-blind cross over study (four week treatment periods) of 11 normotensive patients with stable exertional angina pectoris. Standard recommended doses of both drugs (labetalol 200-400 mg twice daily, nifedipine 10-20 mg three times daily) were used. Angina frequency was similar during the placebo washout period and treatment with the two drugs. The duration of treadmill exercise to angina, ischaemia (greater than 1 mm ST segment depression), and end of exercise was increased by both labetalol and nifedipine when compared with placebo, but there was no difference between the two drugs. Ambulatory ST segment monitoring demonstrated that the frequency, duration and magnitude of ST segment depression, whether painful or silent, were unaffected by either drug. Labetalol is an effective agent in improving exercise tolerance in normotensive patients with stable exertional angina pectoris, with an efficacy similar to that of nifedipine.

Adult↗
PubMed1988

X-linked recessive inheritance of an orofaciodigital syndrome with partial expression in females and survival of affected males.

We describe a family with clinical features of orofaciodigital (OFD) syndrome type 2 or Mohr syndrome, X-linked recessive inheritance and survival of affected males which has not previously been reported. Four affected males in three generations have survived into infancy and two female heterozygotes have very mild expression. Foetal ultrasonography enabled antenatal diagnosis.

Abnormalities, Multiple↗
PubMed1988

Silent myocardial ischaemia in chronic stable angina: a study of its frequency and characteristics in 150 patients.

One hundred and fifty unselected patients with documented coronary artery disease were studied to establish the frequency and characteristics of silent myocardial ischaemia. Patients underwent ambulatory ST segment monitoring off all routine antianginal treatment (total 6264 hours) and exercise testing (n = 146). Ninety one patients (61%) had a total of 598 episodes of significant ST segment change, of which 446 (75%) were asymptomatic. Twenty seven patients (18%) had only painless episodes; 14 (9%) patients only painful episodes; 50 patients (33%) had both painless and painful episodes. The mean number of ST segment changes per day was 2.58 (1.95 silent); however, 11 patients (7%) had 50% of all silent episodes, and 48 patients (32%) had 91% of all silent episodes. Fifty nine patients (39%) had no ST segment changes on ambulatory monitoring, and 73 patients (49%) had no evidence of silent ischaemia. Episodes of silent ischaemia occurred with a similar circadian distribution to that of painful ischaemia, predominantly between 0730 and 1930. There was a similar mean rise in heart rate at the onset of both silent and painful episodes of ischaemia. Silent ischaemia was significantly more frequent in patients with three vessel disease than in those with single vessel disease, and was also significantly related to both time to 1 mm ST depression and maximal exercise duration on exercise testing. There was a highly significant relation between the mean number and duration of episodes of silent ischaemia in patients with positive exercise tests when compared with those with negative tests. No episode of ventricular tachycardia was recorded in association with silent ischaemic change.

Adult↗
PubMed1988

Aluminium encephalopathy: clinical and immunological features.

Aluminium encephalopathy is a specific syndrome occurring in dialysis patients and linked to high aluminium levels in dialysis water. We present the features of 38 cases seen in a single dialysis and transplantation unit. Serum immunoglobulin levels and the prevalence of histocompatibility antigens are discussed. The syndrome in its complete form is specific and easily recognizable. Careful attention to premonitory symptoms may lead to earlier diagnosis.

Aluminum↗
PubMed1987

The pathology of the early and late stages of primary pulmonary hypertension.

During the course of a case of primary pulmonary hypertension occurring in a 24 year old man lung tissue became available at heart-lung transplantation in 1986 and from a lung biopsy carried out in 1981. In 1986 the sections showed classic plexogenic pulmonary arteriopathy. In 1981 they revealed migration of myofibroblasts into the intima and lumen of pulmonary arteries and arterioles, the identification of the cells being confirmed by electron microscopy. During the five years that the pulmonary vascular pathology progressed to the formation of plexiform lesions there was an increase in the number of bronchiolar endocrine cells that were immunoreactive to bombesin and calcitonin. This study demonstrates that the classic pathogenesis of primary plexogenic pulmonary arteriopathy originates years earlier as a migration of cells of muscular pedigree from the media into the intima of the pulmonary arteries and arterioles.

Adult↗
PubMed1986

The diagnosis of aortic root abscess by cross-sectional echocardiography.

Aortic root abscess is frequently a lethal complication of infective endocarditis. Early diagnosis of this complication is of paramount importance because antibiotic therapy is often ineffective and early surgery is probably the treatment of choice. We have compared the diagnostic accuracy of cross-sectional echocardiography with operative findings in the diagnosis of aortic root abscess. Aortic root abscess was diagnosed in nine of 129 patients with infective endocarditis at the National Heart Hospital between 1983 and 1985. Cross-sectional echocardiography demonstrated the presence and location of the aortic root abscess in eight cases; in the ninth case a small abscess was missed. In two other cases, a large abscess was visualised, but abscesses of between 2 mm and 4 mm were missed; the extent and size of large aortic abscesses tended to be underestimated. Echocardiography should be an integral part of the investigation of patients with aortic valve infective endocarditis.

Abscess↗
PubMed1984

Adsorption to fish sperm of vertically transmitted fish viruses.

More than 99 percent of a vertically transmitted fish rhabdovirus, infectious hematopoietic necrosis virus, was removed from suspension in less than 1 minute by adsorption to the surface membrane of sperm from two genera of salmonid fishes. The vertically transmitted, infectious pancreatic necrosis virus adsorbed to a lesser degree, but no adsorption occurred with a second fish rhabdovirus that is not vertically transmitted. Such adsorption may be involved in vertical transmission of these viruses.

Adsorption↗
PubMed1984

Appearance and quantification of infectious hematopoietic necrosis virus in female sockeye salmon (Oncorhynchus nerka) during their spawning migration.

The incidence and amount of infectious hematopoietic necrosis (IHN) virus was determined in 10 organs and body fluids from each of 100 female sockeye salmon (Oncorhynchus nerka) before, during, and after their spawning migration into freshwater. Virus was found in high concentrations only in fish sampled during and after spawning. Infection rates increased from nil to 100 percent within 2 weeks. In spawning fish, incidences of IHN virus were high in all organs and fluids except brain and serum, and the highest concentrations were in the pyloric caeca and lower gut. Immediately before spawning, IHN virus was found most frequently in the gills, less frequently in the pyloric caeca and spleen, and rarely in other organs.

Animals↗
PubMed1984

Comparison of in vitro growth characteristics of ten isolates of infectious haematopoietic necrosis virus.

Ten isolates of infectious haematopoietic necrosis from salmonid fishes of different locations on the West Coast of North America from California to Alaska were compared by plaque size, single-step growth curves at 15 and 18 degrees C, rate of appearance of cytopathic effects in cell cultures, and growth over a range of temperatures. All isolates were distinguishable on the basis of each growth characteristic examined. The CO isolate from the Sacramento River drainage of California was the most singular of the 10 because of its diminutive plaque size and sensitivity to slightly elevated temperatures. The mean plaque diameter of the 10 isolates increased as the latitude of the geographic source of the isolate increased. Although the maximum titre obtained by all isolates was depressed at temperatures above approximately 18 degrees C, half of the isolates were not inhibited by temperatures as low as 0.5 degree C.

Animals↗
PubMed1980

Plaquing procedure for infectious hematopoietic necrosis virus.

A single overlay plaque assay was designed and evaluated for infectious hematopoietic necrosis virus. Epithelioma papillosum carpio cells were grown in normal atmosphere with tris(hydroxymethyl)aminomethane- or HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid)-buffered media. Plaques were larger and formed more quickly on 1- to 3-day-old cell monolayers than on older monolayers. Cell culture medium with a 10% addition of fetal calf serum (MEM 10) or without serum (MEM 0) were the most efficient virus diluents. Dilution with phosphate-buffered saline, saline, normal broth, or deionized water reduced plaque numbers. Variations in the pH (7.0 to 8.0) of a MEM 0 diluent did not affect plaque numbers. Increasing the volume of viral inoculum above 0.15 ml (15- by 60-mm plate) decreased plaquing efficiency. Significantly more plaques occurred under gum tragacanth and methylcellulose than under agar or agarose overlays. Varying the pH (6.8 to 7.4) of methylcellulose overlays did not significantly change plaque numbers. More plaques formed under the thicker overlays of both methylcellulose and gum tragacanth. Tris(hydroxymethyl)aminomethane and HEPES performed equally well, buffering either medium or overlay. Plaque numbers were reduced when cells were rinsed after virus adsorption or less than 1 h was allowed for adsorption. Variation in adsorption time between 60 and 180 min did not change plaque numbers. The mean plaque formation time was 7 days at 16 degrees C. The viral dose response was linear when the standardized assay was used.

Adsorption↗
PubMed1972

Location and description of spiral-shaped microorganisms in the normal rat cecum.

Some indigenous microorganisms have been shown to localize in certain anatomical sites of the digestive tract of mammals. We studied the ceca of normal adult rats by light and electron microscopy to determine whether any specific bacterial population localizes in this area. All rats studied showed that the crypt was packed with organisms whose morphological character differs from those of the cecal lumen. Organisms localized in the crypt were often identified topographically close to the microvilli of the epithelial cells. These organisms could be differentiated into three types according to their characteristic ultrastructure. Type 1 was a thin spiral-shaped microbe that resembled a Borrelia. Type 2 possessed helically coiled fibers and flagella-like appendages. Type 3 was spiral-shaped but lacked axial fibers. Types 1 and 2 were both capable of penetrating through the crypt epithelium into the lamina propria where they were found in either phagocytes or extracellular locations. These observations are discussed in relation to other host-microflora localization patterns.

Animals↗