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Biomedical subjects

M Ryan

Publications and source records attributed to M Ryan.

At least 145 records · Page 8Linked to original sources
PubMed1996

New stone formation: a comparison of extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy.

PURPOSE: There is theoretical concern that stone recurrence rates may be higher following extracorporeal shock wave lithotripsy (ESWL) compared to other techniques because of residual stone debris. MATERIALS AND METHODS: We documented all new stone formations in 298 consecutive patients who initially achieved a stone-free status following ESWL for renal calculi less that 2 cm in largest dimension, and compared the findings to those of 62 patients treated with percutaneous nephrolithotomy without ultrasonic fragmentation. Stone-free status was assessed by a centrally reviewed plain abdominal film and renal tomograms at 3 months. A plain abdominal film was repeated at 12 and 24 months to detect recurrence. RESULTS: New stones formed in 22.2% of patients after ESWL and 4.2% after percutaneous nephrolithotomy at 1 year (p = 0.004), and in 34.8% versus 22.6%, respectively, at 2 years (p =0.190). Furthermore, more new stones recurred in the lower and mid calices compared to baseline location in the ESWL group (chi-square <0.0001), which was not observed in the percutaneous nephrolithotomy group. CONCLUSIONS: Our data support a trend toward higher stone recurrence rates in ESWL treated patients, which may be due to microscopic sand particles migrating to dependent calices and acting as a nidus for new stone formation.

Female↗
PubMed1996

Circadian relationships between circulating atrial natriuretic peptides and serum calcium and phosphate in healthy humans.

Long-acting natriuretic peptide (LANP), vessel dilator (VSDL), and atrial natriuretic factor (ANF) consisting of amino acids (aa) 1 to 30, 31 to 67, and 99 to 126, respectively, of the 126-aa ANF prohormone circulate in humans. Among the biologic properties of these peptides is the ability of ANF to decrease intracellular calcium concentrations. To determine if atrial natriuretic peptides are directly related to serum calcium and/or phosphate in healthy normocalcemic humans, we examined 21 24-hour profiles of VSDL, LANP, ANF, and serum calcium and phosphate in 14 healthy humans. VSDL, LANP, and ANF each had significant (P < .001) circadian rhythms, with peak concentrations late during sleep (at 4:00 AM) being nearly twice the concentrations in the afternoon and evening. Serum calcium and phosphate also had significant circadian rhythms (P < .001) with troughs nearly opposite to those of the atrial natriuretic peptides, suggesting that atrial peptides may be important in the modulation of the circadian rhythms of calcium and phosphate. The nearly identical circadian rhythms of the atrial natriuretic peptides and of parathyroid hormone (PTH) reported by others, along with evidence that PTH may increase atrial peptide release, suggest that some of the effects attributed to PTH may be mediated by atrial natriuretic peptides.

Adult↗
PubMed1996

The organisms reported to cause infective myocarditis and pericarditis in England and Wales.

It is difficult to acquire an overall perspective of the range of organisms responsible for infective myocarditis or pericarditis, and their relative importance, as most studies have involved only case reports or case series of a single organism. This study analyses reports to the Communicable Disease Surveillance Centre, of the Public Health Laboratory Service. Reports where myocarditis or pericarditis was included as the main clinical features between 1990 and 1993 were studied. Between 1990 and 1993, 368 cases of myocarditis and/or pericarditis were reported to CDSC. Viruses were reported to cause 253 (69%) cases, bacteria were responsible for 49 (13%) cases, mycoplasma for 32 (9%) cases, chlamydia for 16 (4%) cases and Mycobacterium tuberculosis for nine (2%) cases. Infection with coxsackie B virus was most frequently associated with a mixed picture of myo/pericarditis, whereas influenzae virus was associated with pericarditis or myocarditis alone. This information will provide clinicians with details of the more likely pathogens responsible for these conditions.

England↗
PubMed1996

The use of magnetic resonance imaging to assess swelling after the removal of third molar teeth.

OBJECTIVE: To assess the suitability and accuracy of magnetic resonance imaging (MRI) in measuring the swelling of the face and lingual tissues after removal of third molar teeth. DESIGN: Prospective open study. SETTING: Teaching hospital, Scotland. SUBJECTS: 5 patients 19-22 years old with bilateral mesioangular impacted wisdom teeth. INTERVENTIONS: Magnetic resonance imaging scans taken before, and 1 and 7 days after, removal of bilateral lower wisdom teeth under general anaesthesia. MAIN OUTCOME MEASURES: Amount of swelling measured postoperatively compared with preoperatively. Coefficient of analytical variation calculated for the main observer, and between him and a second observer to assess accuracy and reproducibility for each examiner and between examiners. RESULTS: Buccal swelling on the first postoperative day was significantly greater than preoperative (P < 0.01). There was no significant difference in lingual swelling. The mean coefficient of variation for the first examiner was 1.92 and there was no significant difference between the two examiners. CONCLUSIONS: Measurements on MRI scans are both recordable and reproducible for buccal swelling, but lingual swelling is more difficult to measure because of problems in defining the lateral border of the tongue. MRI scans provide an objective measurement of swelling after extraction of wisdom teeth and could be used to evaluate the efficacy of drug regimens.

Adult↗
PubMed1996

Estimating the economic benefits of avoiding food-borne risk: is 'willingness to pay' feasible?

In this paper, the results of a pilot study of willingness to pay (WTP) to avoid poultry-borne illness are reported. Through this, the problems of devising an economic measure of the 'intangible' benefits of prevention of food-borne risk are explored. The study is the first to allow those against a prevention policy (irradiation of poultry-meat) to register their WTP not to have the policy implemented. The study demonstrates that it is feasible to obtain answers to WTP questions from a self-selected sample. Future studies should ensure greater representativeness of respondents, that better information about benefits is provided to respondents and that an appropriate method of aggregation of benefits is used.

Adult↗
PubMed1996

Recognition of foot-and-mouth disease virus and its capsid protein VP1 by bovine peripheral T lymphocytes.

The role of T cells in immunity to foot-and-mouth disease virus is still poorly defined compared to that of the humoral response. In this paper we describe a systematic, longitudinal study on the cellular recognition of FMDV and its subunit protein VP1 by bovine peripheral blood T lymphocytes. Multiple vaccination with a single virus serotype induced a serotype cross-reactive proliferative T cell repertoire that varied in magnitude between individual animals and with the serotype of the vaccine used. Primary proliferative T cell responses of vaccinated and acutely infected cattle were weak relative to the magnitude of responses determined for the same animals after boosting. In contrast, the level of circulating antibody produced after both primary and secondary exposure to virus was good. Phenotypic analysis of lymphocytes from vaccinated or infected cattle showed a small increase in CD8+ T cells after infection compared to vaccination. However, in general the profiles of circulating lymphocytes elicited were similar. Thus, we were not able to use proliferative or phenotypic analyses to distinguish between vaccinated and convalescent cattle. T cell recognition of VP1 by multiply-vaccinated cattle was serotype-specific implying that the cross-reactive responses observed with whole virus may be attributed to proteins other than VP1. In contrast to other studies, immunization with recombinant VP1 induced only low levels of neutralizing antibody and failed to elicit profound proliferative responses or protection ever after two immunizations.

Animals↗
PubMed1996

The costs of treating miscarriage: a comparison of medical and surgical management.

OBJECTIVES: To estimate and compare the costs of surgical and medical treatment of miscarriage to the National Health Service. DESIGN: A patient-centred, partially randomised trial. SETTING: A teaching hospital in Scotland. PARTICIPANTS: Four hundred and thirty-seven women with a proven first trimester miscarriage. MAIN OUTCOME MEASURES: The cost per patient of surgical and medical management of miscarriage plus the extra cost per patient of introducing medical management of miscarriage under three different scenarios are calculated. RESULTS: The average cost of surgical treatment was Pounds 397 compared with Pounds 347 for medical treatment. Sensitivity analysis showed that the extra cost of introducing the medical management of miscarriage ranged from a cost saving of Pounds 71 per patient to an additional cost of Pounds 47 per patient. CONCLUSIONS: Our analysis showed that it may be possible to generate cost savings by introducing medical methods in the management of early miscarriage. However, the savings assume that costs associated with theatre use can be fully realised.

Abortion, Induced↗
PubMed1996

Signal transduction in Pneumocystis carinii: characterization of the genes (pcg1) encoding the alpha subunit of the G protein (PCG1) of Pneumocystis carinii carinii and Pneumocystis carinii ratti.

Pneumocystis carinii is a eukaryotic organism that causes pneumonia in immunocompromised hosts. The cell biology and life cycle of the organism are poorly understood primarily because of the lack of a continuous in vitro cultivation system. These limitations have prevented investigation of the organism's infectious cycle and hindered the rational development of new antimicrobial therapies and implementation of measures to prevent exposure to the organism or transmission. The interaction of P. carinii with its host and its environment may be critical determinants of pathogenicity and life cycle. Signal transduction pathways are likely to be critical in regulating these processes. G proteins are highly conserved members of the pathways important in many cellular events, including cell proliferation and environmental sensing. To characterize signal transduction pathways in P. carinii, we cloned a G-protein alpha subunit (G-alpha) of P. carinii carinii and P. carinii ratti by PCR amplification and hybridization screening. The gene encoding the G-alpha was present in single copy on a 450-kb chromosome of P.c. ratti. The 1,062-bp G-alpha open reading frame is interrupted by nine introns. The predicted polypeptide showed 29 to 53% identity with known fungal G-alpha proteins with greatest homology to Neurospora crassa Gna-2. Northern (RNA) blot analysis and immunoprecipitation demonstrated expression of the G-alpha mRNA and protein P. carinii isolated from heavily infected animals. Some alteration in the level of transcription was noted in short-term maintenance in starvation or rich medium. Characterization of signal transduction in P. carinii will permit a better understanding of the reproductive capacity and other cellular processes in this family or organisms that cannot be cultured continuously.

Amino Acid Sequence↗
PubMed1996

Circadian relationships between circulating atrial natriuretic peptides and serum sodium and chloride in healthy humans.

Long-acting natriuretic peptide (LANP), vessel dilator (VSDL), and atrial natriuretic factor (ANF) consisting of amino acids 1-30, 31-67, and 99-126 of the 126 amino acid ANF prohormone, respectively, circulate in humans and have potent natriuretic properties. To determine whether these peptides have a direct relationship to serum Na and/or Cl, we examined 21 24-hour profiles of these peptides and Na and Cl in 14 healthy humans. LANP, VSDL, ANF, and Cl had significant (p < 0.001) circadian rhythms with peak concentrations at 04.00 h. The circadian rhythm of serum Na was exactly opposite. Sodium correlated negatively with LANP (p = 0.021) and ANF (p = 0.007), while Cl correlated positively with LANP (p = 0.003) and VSDL (p = 0.001). These data suggest that the atrial peptides may be important for the maintenance of serum Na and Cl within their normal ranges and in the modulation of their daily circadian rhythms.

Adult↗
PubMed1996

The costs of alternative types of routine antenatal care for low-risk women: shared care vs care by general practitioners and community midwives.

OBJECTIVES: To compare the costs to the health service, women and their families of routine antenatal care provided by either traditional obstetrician-led shared care or general practitioner (GP)/community midwife care. METHOD: A multicentre randomized controlled trial in 51 general practices linked to nine maternity hospitals in Scotland: 1667 low-risk pregnant women provided information on costs to the health service. 704 of these women provided information on non-health service costs. RESULTS: GP/midwife antenatal care was found to cost statistically significantly less than shared care. This was the case for investigations carried out at routine antenatal visits (GP/midwife = 87.25 Pounds, shared care = 91.15 Pounds, P = 0.05), staffing costs at routine antenatal visits (GP/midwife = 127.76 Pounds, shared care = 131.09 Pounds, P = 0.001), and non-health service costs incurred by women and their companions (GP/midwife = 118.53 Pounds, shared care = 133.49 Pounds, P = 0.001). While non-routine care in the GP/midwife arm of the trial costs less than in the shared care arm, the difference was not statistically significant (GP/midwife = 83.74 Pounds, shared care = 94.43 Pounds, P = 0.46). The total societal cost of antenatal care was 417.28 Pounds per women in the GP/midwife arm of the trial and 450.19 Pounds in the shared care arm of the trial. This difference was statistically significant (P < 0.001). The application of sensitivity analysis did not change these results. CONCLUSIONS: GP/midwife antenatal care is a satisfactory option for low-risk pregnant women in Scotland provided that clinical outcomes and women's satisfaction are at least the same as those of women with shared care.

Cost Savings↗
PubMed1996

Do physicians' perceptions of drug costs influence their prescribing?

This study examines general practitioner (GP) attitudes towards and knowledge of prescribing costs, and the influence of these 2 factors in the doctor's demand for drugs. The main emphasis of the study is on the influence of perceived cost of drugs on prescribing habits. A postal questionnaire was sent to all 273 GP principals in the Grampian region of Scotland. This questionnaire assessed GPs' attitudes and knowledge with respect to prescribing costs. Information was also collected on the prescribing habits of 176 of these GPs. This information was linked to look at the influence GPs' knowledge of drug costs has on their actual prescribing behaviour. Three drug groups were studied: ulcer-healing drugs, pain-killers and penicillins. The results showed that although most GPs agreed that costs should be borne in mind when prescribing medicines, their actual knowledge of the drug costs was often inaccurate. Furthermore, for certain therapeutic groups, prescribing habits are influenced by GPs' perceptions of drug costs. This implies that GPs are not as averse to considering costs as is often assumed, and that giving GPs better information about drug costs might promote more rational prescribing.

Attitude of Health Personnel↗
PubMed1996

Yea or Nay?

Explore the source record for details and available documents.

Chief Executive Officers, Hospital↗
PubMed1996

General practitioners and family doctors in the Russian Federation.

This paper looks at the emergence in Russia of a strategy for delivering primary health care which differs radically from the specialist-based system of the former Soviet Union. Drawing on Russian language sources, the paper outlines previous training arrangements, the limited role of 'sector' doctors and the reasons for official endorsement of general practice during the years of perestroika. It reports that the Health Ministry asked all the country's regions to make a gradual transition to general practice in 1992, and that legislation made the choice of family doctor a universal right in 1993. The conclusion refers to factors which are likely to determine whether that right will become a reality.

Family Practice↗
PubMed1996

Reading and utilizing quantitative nursing research: a guide for the neophyte.

Research utilization, that is, applying research findings to practice, is now recognized as essential to developing scientifically based nursing practice. A key step in this process is the ability of nurses to read nursing research studies and determine the usefulness of their findings for practice. This article presents strategies that will help nurses develop or enhance their reading and research skills, enabling fuller participation in the research utilization process.

Diffusion of Innovation↗