Biomedical subjects
Publications and source records attributed to C Roberts.
Methicillin-resistant Staphylococcus aureus (MRSA) has been notifiable in Western Australia since 1985. This article reviews the notification data from 1994 to 1997, focusing on increases in MRSA notifications and the proportion that are local strains; changes in the geographical distribution of MRSA; and changes in antibiotic-resistance patterns.
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STUDY OBJECTIVE: To assess the benefit of planned specialist follow up appointments after elective inpatient surgery. DESIGN: This was a controlled trial, using repeated alternate allocation of time periods to the two study groups. Group 1: Planned outpatient follow up 6-12 weeks after surgery. Group 2: No planned follow up: additional written information for patients and general practitioners. SETTING: A district general hospital in the north west of England. PARTICIPANTS: 264 patients listed for one of: transurethral resection of the prostate, varicose vein surgery, cholecystectomy (open or laparoscopic), inguinal herniorraphy (open or laparoscopic). MAIN OUTCOME MEASURES: Health status, complications, return to normal activity, patient satisfaction, use and costs of primary and secondary care in the 12 weeks after surgery. MAIN RESULTS: Data were available for 212 (80%) of eligible patients. Thirty eight per cent of patients in the "no planned follow up" group were in fact seen in outpatients after their discharge. Intention to treat analysis showed that there were no significant differences between the groups for health status, complications, or time to return to normal activity. Patients in the "no planned follow up" group had significantly fewer hospital visits and costs (mean difference in visits 0.51, 95% confidence intervals 0.39 to 0.69; mean difference in hospital costs 12.75 Pounds, 9.75 Pounds to 15.50 Pounds). There were fewer primary care staff contacts and costs in the "no planned follow up" group, although this difference was not significant (mean difference = 0.61 visits, -0.13 to 1.33 visits; primary care costs difference 8.37 Pounds, -1.31 Pounds to 18.73 Pounds). Patients in the "no planned follow up group" had significantly reduced patient travel costs (mean difference 4.84 Pounds, 3.44 Pounds to 6.22 Pounds). Eighty nine (42%) patients would prefer to be followed up by both their hospital doctor and GP; 53 (25%) patients would prefer to be followed up by the hospital doctor only. There were no significant differences between the two groups in their preferences for follow up. The majority of GPs agreed with the statement that a policy of no follow up at hospital outpatients for each of the six surgical procedures would increase their workload. CONCLUSIONS: Planned outpatient appointments after uncomplicated surgery seem to be neither necessary nor cost effective. A policy of "no planned follow up" results in no increase in primary care costs, and savings in hospital and patient costs. However, many patients expected and wanted to be seen again by their surgeon and GPs were concerned that a "no follow up" policy would result in an increase in workload.
We explore a range of linear regression models that might be useful for either: (a) the relative calibration of two or more methods or (b) to evaluate their precisions relative to each other. Ideally, one should be able to use a single data set to carry out the jobs (a) and (b) together. Throughout this review we consider the constraints (assumptions) needed to attain identifiability of the models and the possible pitfalls to the unwary in having to introduce them. We also pay particular attention to the possible problems arising from the presence of random matrix effects (reproducible random measurement 'errors' that are characteristic of a given method when being used on a given specimen or sample, i.e. specimen specific biases or subject by method interactions). Finally, we stress the importance of a fully-informative design (using replicate measurements on each subject using at least three independent methods) and large sample sizes.
The assessment and treatment of deaf children with psychiatric disorder is intimately related to the individual child's communication, which in turn is affected by a number of factors, medical, social, and cultural. The deafness can be aetiologically related to the psychiatric disorder or can be incidental. Treatment strategies should be adapted to meet the individual child and family's needs. Deaf professionals have a vital role in mental health services for this population. The use of an interpreter can clarify communication and cultural issues for deaf and hearing children, families, and professionals.
BACKGROUND: The supply of general practitioners (GPs) in the National Health Service (NHS) is dynamic and there are fears that there will be an inadequate number of doctors to meet the needs of the NHS. There are particular concerns about changes in the career trajectory of young GPs and what they mean for overall supply. AIM: To identify predictors of retention among young, new entrant GPs entering the NHS between 1 October 1991 and 1 October 1992. METHOD: Two-year retention rates of young (35 years of age or less) new entrant GPs have been modelled using a multilevel logit model. Retention is defined as young, new entrant GPs remaining in their initial health authority for two years or more. RESULTS: Two hundred and fifty-two (13.0%) members of the study group left general practice within two years of entry (i.e. were not retained). Sex (females had lower retention [95% CI = 0.43-0.75]), practice size (young GPs in larger practices had higher retention [95% CI = 1.10-1.29]), and belonging to a practice in one of 16 Greater London Health Authorities (which had lower retention [95% CI = 0.39-0.82]) were identified as major predictors of retention. Deprivation, measured at the individual GP patient list level, had a very slight association with retention (P = 0.097; 95% CI = 1.00-1.02). Deprivation measured at the health authority level (95% CI = 0.99-1.01) was not found to be a statistically significant predictor of retention (P = 0.83). CONCLUSION: None of the statistically significant predictors of retention suggest any policy panacea to end this phenomenon. The challenge for policy is to learn to deal with the dynamic nature of the GP workforce with a non-crisis mentality.
Despite the recent introduction of several new agents into the fibrinolytic market, none have proven more efficacious than earlier agents. However, new routes of administration may provide some benefit in terms of time to treatment and ease of administration. The best possibility for breaking the therapeutic ceiling is in finding new ways to use fibrinolytic agents, such as combination therapy with GP IIb/IIIa inhibitors and low-molecular-weight heparin. Use with PCI may decrease mortality rates in some patient groups. Prehospital administration of fibrinolytics is also an option for expediting care and improving outcomes.
A new anatomical variation of extensor digiti minimi (EDM) was discovered during our anatomical studies. The EDM usually gives one tendon to the little finger to extend the metacarpophalangeal joint (MPJ) independently from the other fingers. The EDM in our cadaver had three tendon slips. It supplied the MPJ of the little finger with two tendon slips. Along with the extensor digitorum communis (EDC), the EDM also had an additional slip to the ring finger MPJ extensor hood apparatus. The little finger also received a separate tendon from EDC.
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The questions of whether different tautomeric forms of nucleic acid bases exist to any significant extent in DNA, or what their possible roles in mutation may be, are under intense scrutiny. 2'-Deoxyisoguanosine (iG) has been suggested to have a propensity to adopt the enol form. Isoguanine (also called 2-hydroxyadenine) can be found in oxidatively damaged DNA generated from treating DNA with a Fenton-type reactive oxygen-generating system and is known to cause mutation. We have analyzed the three-dimensional structure of the DNA dodecamer d(CGC[iG]AATTTGCG) (denoted iG-DODE) by X-ray crystallography and NMR. The crystal structure of the iG-DODE complexed with the minor groove binder Hoechst 33342, refined to 1.4 A resolution, showed that the two independent iG.T base pairs in the dodecamer duplex adopt different (one in Watson-Crick and the other in wobble) conformations. The high-resolution nature of the structure also affords unprecedented clear information about the conformation and interactions of the Hoechst drug. The Hoechst 33342 binds in the narrow minor groove at the iGAATT site, with the N-methylpiperazine ring near the iG4.T21 base pair. Three hydrogen bonds are found between the NH of the Hoechst ligand and T-O2 DNA atoms. In solution, the two iG.T base pairs in iG-DODE predominantly are in the wobble form at 2 degreesC. At higher temperatures, another duplex form (likely involving the enol form of iG) is in slow exchange with the keto form and becomes significantly populated, reaching approximately 40% at 40 degreesC. Our data support the conclusion that iG pairs with T in a Watson-Crick configuration to a significant extent at physiological temperature (37 degreesC), which may explain the facile incorporation rate of T across from an iG during in vitro DNA replication.
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This study describes trends in reports of pertussis in South Australia. Data were analysed from three sources: mortality data since 1893 from South Australian yearbooks, notification data from 1917, and hospitalisation data for pertussis or related complications since July 1985. Crude and age-specific rates of mortality, notifications and hospitalisation were compared. Pertussis peaked in 3 to 5 yearly cycles. The mortality and notification rates have generally declined over time. However, since 1993 the notification rate has remained high. The median age for pertussis notifications increased from 4 years in 1984 to 15 years in 1996. Serological testing for pertussis was included in 15% of notifications in 1985 and 90% in 1996. The age specific hospitalisation rate for pertussis was highest in infants < or = 6 months. Since the turn of the century, mortality and notification rates due to pertussis have declined. Over the past decade the major burden of severe disease resulting in hospitalisation has been borne by infants < or = 6 months. These infants are too young to be afforded protection from three primary immunisations against pertussis. Despite no substantial increase in mortality nor hospitalisation for pertussis in South Australia, the notification rate has remained high since 1993. This increase may be attributable to the use of more sensitive tests for pertussis, such as serology.
The effect of SB-224289 (2,3,6.7-tetrahydro-1'-methyl-5-¿2'-methyl-4'-[(5-methyl-1,2,4-oxadiazol e-3-yl)biphenyl-4-yl]carbonyl¿Furo[2,3-F]-indole-3-spiro-4'-piperidine oxalate) (4 mg/kg i.p., 5-HT1B receptor antagonist), GR 127935 (N-[4-methoxy-3-(4-methyl-1-piperizinyl)phenyl]-2'-methyl-4'-(5-me thyl-1,2,4-oxadiazole-3-yl)[1,1'-biphenyl]-carboxamide) (0.3 mg/kg i.p., 5-HT1B/1D receptor antagonist), and paroxetine (10 mg/kg p.o.) were investigated on extracellular 5-hydroxytryptamine (5-HT) levels in the frontal cortex, striatum and dentate gyrus of the freely moving guinea-pig with microdialysis. In the frontal cortex and striatum (dorsal raphe innervated areas), GR 127935 evoked a significant decrease in extracellular 5-HT, reaching minima of 41+/-12% and 32+/-6% of basal, respectively. This decrease may be explained by antagonism of inhibitory 5-HT1B/1D receptors on raphe cell bodies, leading to a local increase in 5-HT, which, in turn, stimulated 5-HT1A receptors to decrease cell firing, and hence 5-HT release from terminals. In contrast, SB-224289 had no effect on 5-HT levels in either region. In the dentate gyrus (median raphe innervated area), GR 127935 and SB-224289 significantly increased extracellular 5-HT, reaching maxima of 146+/-11% and 151+/-19% of basal, respectively. The ability of both compounds to increase 5-HT levels in the dentate gyrus suggests a lack of 5-HT1B/1D receptors in the median raphe nucleus. Paroxetine produced a small but non-significant increase in extracellular 5-HT in the frontal cortex, and a small decrease in the dentate gyrus. The lack of effect of paroxetine in terminal areas may be due to the limiting effects of cell body 5-HT autoreceptors. In summary, the above data demonstrate that 5-HT1B/1D receptor antagonists increase 5-HT levels in the dentate gyrus, implying that acute administration of 5-HT1B/1D receptor antagonists will achieve a similar effect to chronic selective serotonin re-uptake inhibitor treatment in median raphe innervated areas. This, in turn, suggests that such compounds may be efficacious in the treatment of depression.
5-HT1 receptors are members of the G-protein-coupled receptor superfamily and are negatively linked to adenylyl cyclase activity. The human 5-HT1B and 5-HT1D receptors (previously known as 5-HT1Dbeta and 5-HT1Dalpha, respectively), although encoded by two distinct genes, are structurally very similar. Pharmacologically, these two receptors have been differentiated using nonselective chemical tools such as ketanserin and ritanserin, but the absence of truly selective agents has meant that the precise function of the 5-HT1B and 5-HT1D receptors has not been defined. In this paper we describe how, using computational chemistry models as a guide, the nonselective 5-HT1B/5-HT1D receptor antagonist 4 was structurally modified to produce the selective 5-HT1B receptor inverse agonist 5, 1'-methyl-5-[[2'-methyl-4'-(5-methyl-1,2, 4-oxadiazol-3-yl)biphenyl-4-yl]carbonyl]-2,3,6, 7-tetrahydrospiro[furo[2,3-f]indole-3,4'-piperidine] (SB-224289). This compound is a potent antagonist of terminal 5-HT autoreceptor function both in vitro and in vivo.
To investigate the reliability of nominal scales, Kraemer proposed a measurement model from which kappa coefficients could be derived. More recently she suggested a matrix of coefficients as a comprehensive summary of reliability, contrasting this with use of a single summary kappa statistic. The main diagonal of the matrix consists of binary kappa coefficients for each category which measure the reliability of each category relative to all others, while the off-diagonal elements are correlation coefficients for pairs of categories. The off-diagonal elements were suggested as measures of confusion between categories. Schouten also suggested coefficients to assess confusion between pairs of categories, which might be used as alternative off-diagonal elements in a summary matrix. The two types of off-diagonal element will be compared. It will be shown that Schouten's coefficients can be expressed in terms of the parameters of Kraemer's measurement model and that they are more easily interpreted as measures of confusion. First, the maximum value for Schouten's coefficient is one. Secondly, for any pair of categories, Schouten's coefficient equals the proportionate reduction in the probability of classifying a subject in one category of the pair having previously classified them in the other. Thirdly, where the coefficient for a pair of categories is less than the summary kappa statistic, it will be shown that combining these two categories will increase the value of the summary kappa statistic. The methods of analysis are applied to data from a study of the reliability of psychiatric diagnosis and used to identify pairs of classifications between which there is substantial confusion.
BACKGROUND: Studies were conducted to determine the capability of a hydrogen peroxide gas plasma sterilization process to inactivate several types of viruses. Six test agents were used: HIV type 1, human hepatitis A virus, respiratory syncytial virus, vaccinia, herpes simplex virus type 1, and poliovirus type 2. METHODS: The test viruses were suspended in cell culture medium and dried on the bottom of sterile glass petri dishes. The inoculated dishes were processed in the hydrogen peroxide gas plasma system for half the normal sterilization cycle time. Four inoculated carriers for each virus were used in two separate half cycles. Infectivity of the test viruses and cytotoxicity to the indicator cell lines were assayed. RESULTS: The hydrogen peroxide gas plasma sterilization process produced inactivation of the six viral test agents under these experimental conditions. The reduction in viral titers ranged from 2.5 log10 to 5.5 log10, a 99.68% to 99.999% decrease. CONCLUSIONS: These results clearly demonstrate the virucidal effectiveness of the hydrogen peroxide gas plasma sterilization process against both lipid and nonlipid viruses.