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Biomedical subjects

P Murphy

Publications and source records attributed to P Murphy.

At least 199 records · Page 11Linked to original sources
PubMed1991

Effects of retinoic acid excess on expression of Hox-2.9 and Krox-20 and on morphological segmentation in the hindbrain of mouse embryos.

Mouse embryos were exposed to maternally administered RA on day 8.0 or day 7 3/4 of development, i.e. at or just before the differentiation of the cranial neural plate, and before the start of segmentation. On day 9.0, the RA-treated embryos had a shorter preotic hindbrain than the controls and clear rhombomeric segmentation was absent. These morphological effects were correlated with alterations in the spatiotemporal distribution patterns of two genes, Hox-2.9 and Krox-20, which are expressed in the otic and preotic hindbrain and in specific neural crest cell populations. Hox-2.9 was expressed throughout the preotic hindbrain region, instead of being confined to rhombomere 4. Krox-20 was not expressed rostral to the Hox-2.9 domain, i.e. its normal rhombomere 3 domain was absent. The Hox-2.9/Krox-20 boundary was ill-defined, with patches of alternating expression of the two genes. In migrating neural crest cells, Hox-2.9 expression was both abnormally extensive and abnormally prolonged. Neural crest cells expressing Krox-20 remained close to the neural tube. Embryos exposed to RA on day 8 1/4 appeared to be morphologically normal. We suggest that early events leading to rhombomeric segmentation and rhombomere-specific gene expression are specifically vulnerable to raised RA levels, and may require RA levels lower than those in the region of somitic segmentation.

Animals↗
PubMed1991

Cognitive ergonomics of a mail order filling company: part 1 - influence of colour, position and highlighting on recognition time.

Filling mail order request forms requires the picker to determine if the items ordered on the form are in his/her bay, reading the bin address and picking the item. An order form was investigated to determine if ergonomics improvements would result in improved productivity and accuracy. Colour, position and highlighting cues were systematically varied in a computer-simulated version of the picking task. It was concluded that colour and position significantly influence the processing time, while highlighting had no effect on processing time. Expert pickers were slower, but more accurate than the novice pickers. Recommendations for improving the order forms were made and implemented, with very encouraging results.

Journal Article↗
PubMed1991

Xanthine oxidase/dehydrogenase in mammary gland of mouse: relationship to mammogenesis and lactogenesis in vivo and in vitro.

Xanthine oxidase/dehydrogenase (XO/XDH) increases at mid gestation in mammary gland but not in liver of the mouse and remains elevated until the pups are weaned at 20 d post partum. The increase in enzyme activity is due neither to alteration in activators or inhibitors nor to a production of a variant enzyme with altered catalytic properties. The increase is preceded in vivo by a surge of prolactin-like activity (placental lactogen) in plasma, and prolactin is required for induction of XO/XDH in explant culture in vitro. Induction of XO/XDH in vivo and in vitro precedes the full histological differentiation of the gland. In addition, induction of XO/XDH in vitro occurs more rapidly and at lower concentrations of prolactin than does histological differentiation. Thus although XO/XDH is present in milk, increased XO/XDH activity is an early event in mammogenesis in vivo and in vitro rather than a terminal component of differentiation.

Animals↗
PubMed1991

Effect of prior administration of cold saline on pain during propofol injection. A comparison with cold propofol and propofol with lignocaine.

A single-blind, randomised, controlled study was undertaken to compare the efficacy of three methods of preventing pain during injection of propofol on induction of anaesthesia. Patients were allocated randomly to receive unmodified propofol, propofol with 0.05% lignocaine, propofol at 4 degrees C and unmodified propofol preceded by 10 ml of 0.9% saline at 4 degrees C. Prior injection of cold saline reduced the incidence of pain and discomfort significantly (22%) compared with unmodified propofol (75%; p less than 0.005) and was similar to that after cold propofol (33%) and propofol with lignocaine (44%). There was no significant difference between the treatment groups.

Adult↗
PubMed1991

Effect of atrial pacing on the frequency of tachycardia in patients with recurrent junctional tachycardia.

In order to assess whether atrial pacing reduced the frequency of tachycardia in patients with recurrent junctional tachycardias, ten patients with recurrent junctional tachycardias with atrial Intertach antitachycardia pacemakers in situ were paced in a random order in atrial demand mode at 50 ppm (AAI 50), 80 ppm (AAI 80), and 100 ppm (AAI 100) for a period of up to 1 month. The numbers of tachycardias detected by the pacemaker over this period were recorded and compared with the number seen when unpaced (000). Correct arrhythmia detection by the pacemaker was confirmed by Holter monitoring. The number of tachycardias in 000 was 44.7 +/- 19.8 (mean +/- SEM). No significant reduction in tachycardia frequency was seen in any pacing mode. Back-up atrial pacing at 50 ppm tended to reduce the frequency of tachycardias (32.3 +/- 12.8 tachycardias; P = 0.06). The higher pacing rates increased the number of tachycardias (AAI 80; 57.1 +/- 24.6 tachycardias, P = 0.20: AAI 100; 81.8 +/- 30.2 tachycardias; P = 0.31). Symptoms increased with each pacing mode and palpitations were statistically more severe in AAI 100 mode. Four patients had disabling symptoms at this rate and had to drop out. Atrial back-up pacing may be of use in some patients with junctional tachycardia, but overdrive pacing is not helpful.

Adult↗
PubMed1991

An experimental analysis of perfectionism and dissatisfaction.

The striving after perfection has been often mentioned in clinical literature; however, there have been few systematic analyses of the concept. In the present study, a questionnaire measure of Perfectionism and General Dissatisfaction (the SCANS) together with the Eysenck Personality Questionnaire and measures thought to gauge aspects of perfectionistic thinking, were administered to a mixed group of 148 subjects, including 25 eating disorder patients. Perfectionism was found to correlate negatively with Psychoticism (as measured by the EPQ) and positively with the Lie scale. Thus Perfectionism appears to be associated with a tendency to deny personally deviant behaviour and to present oneself in the best possible light. It is also associated with greater accuracy in a visual search task. General Dissatisfaction was correlated significantly with Neuroticism, Introversion and Psychoticism. It thus appears to be related to a combination of 'neurotic introversion' and 'personality deviance'. It is also associated with a tendency to be under-inclusive, that is to find difficulty in ruling out irrelevant stimuli when forming categories. Dissatisfaction was also associated with increased reaction time in the visual search task, perhaps also a reflection of an inability to ignore irrelevant stimuli. Only the EPQ N and P scales successfully differentiated neurotic or dissatisfied perfectionists from normal or satisfied perfectionists, although several measures derived from the visual search task produced results which were approaching significance.

Adult↗
PubMed1991

Comparison of Directigen FLU-A with viral isolation and direct immunofluorescence for the rapid detection and identification of influenza A virus.

Directigen FLU-A, an enzyme immunoassay membrane test, was compared prospectively to isolation in cell culture and direct immunofluorescence (IF) for the detection of influenza A virus. One hundred ninety specimens were evaluated by Directigen FLU-A and cell culture; 184 of these specimens were also tested by direct IF. The sensitivity of Directigen FLU-A compared to isolation in cell culture and direct IF was 100%. The specificities of Directigen FLU-A compared to isolation and direct IF were identical, 91.6%. Fourteen specimens that were positive by Directigen FLU-A did not yield virus in culture; two of the specimens, however, were positive by direct IF, and four other specimens were not specimens of choice for the test. A positive Directigen result had positive predictive values of 62.6 and 75.0% compared to isolation and direct IF, respectively; a positive Directigen result with an intensity reading of 2+ or greater, however, had positive predictive values of 85 and 100% compared to isolation and direct IF, respectively. In all comparisons, the negative predictive value was 100%. There was no evidence that cross-reactivity occurred with non-influenza A antigens. Directigen FLU-A should serve as a convenient screening test for influenza A and as a rapid test supported by isolation in cell culture during an influenza outbreak.

Antigens, Viral↗
PubMed1991

Double partitioning of the left atrium: a previously unreported echocardiographic finding in a case in which transoesophageal echocardiography aided operative resection.

Precordial echocardiography showed two membranes obstructing pulmonary venous return in the left atrium of a 9 month old infant. This anomaly has not previously been described; therefore transoesophageal echocardiography was performed at the time of surgery. This confirmed the anatomy and aided complete resection of both membranes. Even in small infants transoesophageal echocardiography can provide useful information about complex atrial malformations.

Echocardiography↗
PubMed1991

Expression of the mouse labial-like homeobox-containing genes, Hox 2.9 and Hox 1.6, during segmentation of the hindbrain.

The sequence of a mouse Hox 2.9 cDNA clone is presented. The predicted homeodomain is similar to that of the Drosophila gene labial showing 80% identity. The equivalent gene in the Hox 1 cluster is Hox 1.6 which shows extensive similarity to Hox 2.9 both within and outside the homeodomain. Hox 2.9 and Hox 1.6 are the only two mouse members of the labial-like family of homeobox-containing genes as yet identified. Hox 2.9 has previously been shown to be expressed in a single segmental unit of the developing hindbrain (rhombomere) and has been predicted to be involved in conferring rhombomere identity. To analyse further the function of Hox 2.9 during development and to determine if the other mouse labial-like gene Hox 1.6, displays similar properties, we have investigated the expression patterns of these two genes and an additional rhombomere-specific gene, Krox 20, on consecutive embryonic sections at closely staged intervals. This detailed analysis has enabled us to draw the following conclusions: (1) There are extensive similarities in the temporal and spatial expression of Hox 2.9 and Hox 1.6, throughout the period that both genes are expressed in the embryo (7 1/2 to 10 days). At 8 days the genes occupy identical domains in the neuroectoderm and mesoderm with the same sharp anterior boundary in the presumptive hindbrain. These similarities indicate a functional relationship between the genes and further suggest that the labial-like genes are responding to similar signals in the embryo. (2) By 9 days the neuroectoderm expression of both genes retreats posteriorly along the anteroposterior (AP) axis. The difference at this stage between the expression patterns is the persistence of Hox 2.9 in a specific region of the hindbrain, illustrating the capacity of Hox 2.9 to respond to additional positional regulatory signals and indicating a unique function for this gene in the hindbrain. (3) The restriction of Hox 2.9 expression in the hindbrain occurs at 8 1/2 days, approximately the same time as Krox 20 is first detected in the posterior adjoining domain. The mutually exclusive expression of Hox 2.9 and Krox 20 demarcated by sharp expression boundaries suggest that compartmentalisation of cells within the hindbrain has occurred up to 6 h before rhombomeres (morphological segments) are clearly visible. (4) Hox 2.9 expression is confined to the region of rhombomere 4 that shows cell lineage restriction and, unlike Krox 20, is expressed throughout the period that rhombomeres are visible (to 11 1/2 days).(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Sequence↗
PubMed1991

Staging and prognostic factors in nonseminomatous testicular cancer.

Staging of nonseminomatous testicular cancers, as with other tumors, renders important prognostic information and is necessary for making appropriate treatment recommendations. There is no universally accepted staging system for testis cancer, however. Despite the lack of uniformity, most of the staging systems in use today are capable of segregating patients into a "good-risk" or "poor-risk" category. The former group experiences cure less frequently and are appropriate candidates for investigational treatment. Tumor bulk is the most important prognostic factor in virtually all staging systems.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Management of acute coronary occlusion during percutaneous transluminal coronary angioplasty: experience of complications in a hospital without on site facilities for cardiac surgery.

OBJECTIVE: To determine whether percutaneous transluminal coronary angioplasty may be safely performed in cardiology centres in the United Kingdom without immediate on site cardiac surgical cover for complications arising at angioplasty. DESIGN: Retrospective review of coronary angioplasties and complications in a hospital without on site cardiac surgical cover. SETTING: All angioplasties were performed in the catheterisation laboratory of the Belfast City Hospital. Revascularisation surgery for complicated coronary angioplasty was performed in the cardiac surgical unit of the Royal Victoria Hospital, 2.4 km away from the catheterisation laboratory. PATIENTS: 540 Coronary angioplasties were performed on 512 patients between late 1982 and November 1988. Indications included stable angina, unstable rest angina, and suitable coronary disease at coronary arteriography after myocardial infarction. MAIN OUTCOME MEASURES: In hospital mortality after complicated coronary angioplasty and delay to surgical revascularisation after acute coronary occlusion at angioplasty. RESULTS: Coronary angioplasty was successful in 444 cases (82%). Acute coronary occlusion occurred in 35 cases (6.5%). Twelve patients required urgent revascularisation surgery and were transferred safely to the surgical unit; none of these patients died. A mean delay of 268 minutes (range 180-390 minutes) occurred before revascularisation compared with 273 minutes (range 108-420 minutes) in the Royal Victoria Hospital, where on site surgical cover was available. The principal cause of delay was the wait for a cardiac operating theatre to become available and not the transfer time between hospitals. Five deaths occurred after coronary angioplasty, a mortality of 0.9%. Three deaths were related to acute coronary occlusion. The absence of immediate surgical help did not influence the outcome in any patient. CONCLUSION: With careful selection of patients coronary angioplasty may be safely performed in a hospital without on site cardiac surgical facilities, provided that these are available at a nearby centre.

Acute Disease↗
PubMed1990

The clinical spectrum of endophthalmitis: incidence, predisposing factors, and features influencing outcome.

Endophthalmitis is a virulent ocular inflammation typically developing suddenly and progressing rapidly. To better understand the incidence and factors predisposing to infection and influencing outcome, records of 114 patients with endophthalmitis hospitalized at one institution from 1980 to 1986 were reviewed. An infectious origin was confirmed in 79 patients (69%). The most common pathogens included staphylococcal species (Staphylococcus epidermidis, 33 cases; Staphylococcus aureus, 8 cases), streptococci (18 cases), gram-negative organisms (10 cases), and fungi (7 cases). Predisposing factors for infective endophthalmitis included preceding ocular surgery (67%), penetrating trauma (13%), systemic infection (11%), and periocular infection (5%). Despite vitrectomies and aggressive use of antibiotics, 42 patients (53%) with infective endophthalmitis suffered major visual loss. Morbidity was less pronounced with infection caused by S. epidermidis (23%; P less than .05). Patients with infective endophthalmitis more likely required repeated vitrectomies, were hospitalized longer, and had a worse outcome (as measured by complete enucleation) than those with "sterile" endophthalmitis. On the basis of these data, empiric vancomycingentamicin might be initiated in patients with endophthalmitis. Studies to define optimal management are needed, because the morbidity associated with this entity remains pessimistically high despite state-of-the-art treatment.

Adolescent↗
PubMed1990

Training-induced alterations in muscle glycogen utilization in fibre-specific types during prolonged exercise.

Using the glycogen depletion technique, we have examined utilization of specific fibre types during prolonged submaximal exercise to investigate the recruitment pattern employed by the central nervous system to sustain force generation in the face of a progressive glycogen depletion. Six male subjects (Vo2 max, 52.8 +/- 2.5 mL.kg-1.min-1, mean +/- SE) cycled at 59% of pretraining Vo2 max (the same absolute power output) for 99.5 +/- 6 min on two occasions, before training and after 10-12 days of intensive training, involving 2 h of cycling per day. Prior to the training, glycogen concentration during exercise in the type I and type IIA fibres of the vastus lateralis muscle as measured by microphotometric techniques was progressively reduced during exercise. The pattern of depletion in both of these fibre types was parallel and showed an early marked depletion amounting to 51 (p less than 0.05) and 35% (p less than 0.05) in the type I and type IIA fibres, respectively, during the first 15 min of exercise. At the end of exercise, glycogen levels in type I and type IIA fibres were reduced to 9 and 44% of initial levels, respectively. In contrast, glycogen concentration in type IIB fibres was not significantly (p less than 0.05) altered throughout the exercise. Following training, a pronounced glycogen sparing occurred that was conspicuous in only the type I and type IIA fibres, which was most pronounced during the first 15 min of the exercise. Similar to pretraining, glycogen concentrations in type IIB fibres were unaffected by either exercise or training.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Randomized trial of laser-assisted passage through occluded femoro-popliteal arteries.

A randomized trial was carried out in patients with occlusions of the femoro-popliteal artery to compare the passage of metal-tipped optical fibres with guide wires and catheters through the occlusions, prior to balloon angioplasty. The study was in a provincial English teaching hospital providing a vascular service for the area. Fifty patients were entered; 25 into the "laser" group and 25 into the "control" group. End points were (a) the success in passage through the occlusion and (b) the outcome 1 month after passage. Comparison of the groups showed no appreciable difference between the two methods with regard to age, sex, symptoms, incidence of diabetes, or previous myocardial infarctions. Successful passage through the occlusion followed by dilatation was achieved in 18 (72%) patients in the laser group and 20 (80%) in the control group. After 1 month, 13 (52%) arteries in the laser group were patent compared to 13 (57%) in the control group. Confidence limits for the difference in success of passage are -15% to +31%, and -24% to +33% for patency after 1 month. Since these limits include zero, it is unlikely that a longer trial would alter the difference between the two methods. The results suggest that the laser system currently in use is no better than conventional methods.

Adult↗
PubMed1990

Management of congenital tracheal stenosis in infants.

Until recently congenital tracheal stenosis presenting in infants was considered to be almost invariably lethal. With improved diagnostic, anaesthetic and surgical techniques virtually all cases are potentially curable. Prompt recognition and early surgical intervention, combined with skilled perioperative management, will result in a more favourable outcome.

Anesthesia, General↗
PubMed1990

Postnatal depression--aetiological factors.

One hundred and forty-two women at six weeks postpartum were asked to complete Cox's Edinburgh Postnatal Depression Scale. Thirty-eight scored positively for depression and 28 of these were followed up by a psychiatrist. Twenty-eight controls were randomly selected from those who scored negatively. Numerous variables were considered, including the type of labour, whether the mother was breastfeeding or not, and the presence or absence of a psychiatric history. In addition the depressed group completed the Eysenck Personality Inventory. A past psychiatric history was found to be a very significant risk factor and there is a definite association between postnatal depression and delivery by forceps, vacuum or caesarian section. Maternal age and breastfeeding were not found to be of aetiological significance.

Depression↗