Biomedical subjects

J Hayes

Publications and source records attributed to J Hayes.

At least 19 recordsLinked to original sources

PubMed2006

Cerebral metabolites in HIV-infected children followed for 10 months with 1H-MRS.

BACKGROUND: Previous studies have shown that HIV-infected children have abnormal cerebral metabolites, measured by proton MR spectroscopy (1H MRS), but the stability of these measurements over time has not been described in HIV-infected children. The authors recently reported a study of cerebral metabolites in 20 HIV-infected children (6 to 16 years of age); the current study followed 12 of these children (10.0 years +/- 3.7 years) and repeated the MR spectroscopy at 24.1 +/- 3.7 weeks and 42.2 +/- 3.5 weeks following the entry time with repeated neuropsychological testing. METHODS: 1H MR spectra were acquired at 1.5 T (GE Signa, PRESS localization, repetition time = 3,000 msec, echo time = 30 msec). Five brain regions were studied: right frontal white matter, left frontal white matter, right basal ganglia, right hippocampus, and midfrontal gray matter. The concentrations of N-acetylaspartate (NAA), choline (CHO), creatine (CR), and myo-inositol (mI) and the ratio of each metabolite to CR were determined. RESULTS: There were no changes in the metabolite concentrations or metabolite/CR ratios at the three time periods. Similarly, during this follow-up period, HIV-positive children showed no changes in clinical signs, HIV viral loads, CD4%, or CD4 counts, except for improved spatial memory with repeat testing. CONCLUSION: In a clinically and neurologically stable group of HIV-infected children, cerebral metabolites were stable over a 10-month time period, suggesting that it is possible to assess changes in cerebral metabolites as a measure of cerebral health, but longer follow-up in a larger sample is needed.

Adolescent↗

PubMed2006

Development of gastric slow waves and effects of feeding in pre-term and full-term infants.

The aims of this study were to investigate the difference in developmental process of gastric slow waves and the effects of feeding in pre-term and full-term infants. Twenty-six pre-term and 31 full-term infants were enrolled in the study. Gastric myoelectrical activity was recorded using electrogastrography (EGG) from birth to month 6. An increase in the % of 2-4 cpm slow waves was noted in both pre-term (P < 0.01) and full-term infants (P < 0.04) from birth to month 4. The pre-term infants showed a reduced dominant EGG power at certain points of the study. (3) Breast or formula feeding resulted in no difference in the EGG in the full-term infants and showed a difference in the postprandial dominant power of the EGG in the pre-term infants only at month 2 after birth (P < 0.05) but not at other times. The gastric slow wave in pre-term infants is of a significantly reduced amplitude but similar rhythmicity. The method of feeding has no effects on the EGG in full-term infants and minimal effects (may be of non-clinical significance) on the EGG in pre-term infants as the difference was noted only at one time point during the 6-month follow-up study.

Bottle Feeding↗

PubMed2006

Phenotypic characterization of Streptococcus pneumoniae biofilm development.

Streptococcus pneumoniae is among the most common pathogens associated with chronic otitis media with effusion, which has been hypothesized to be a biofilm disease. S. pneumoniae has been shown to form biofilms, however, little is known about the developmental process, the architecture, and the changes that occur upon biofilm development. In the current study we made use of a continuous-culture biofilm system to characterize biofilm development of 14 different S. pneumoniae strains representing at least 10 unique serotypes. The biofilm development process was found to occur in three distinct stages, including initial attachment, cluster formation, and biofilm maturation. While all 14 pneumococcal strains displayed similar developmental stages, the mature biofilm architecture differed significantly among the serotypes tested. Overall, three biofilm architectural groups were detected based on biomass, biofilm thickness, and cluster size. The biofilm viable cell counts and total protein concentration increased steadily over the course of biofilm development, reaching approximately 8 x 10(8) cells and approximately 15 mg of protein per biofilm after 9 days of biofilm growth. Proteomic analysis confirmed the presence of distinct biofilm developmental stages by the detection of multiple phenotypes over the course of biofilm development. The biofilm development process was found to correlate not only with differential production of proteins but also with a dramatic increase in the number of detectable proteins, indicating that biofilm formation by S. pneumoniae may be a far more complex process than previously anticipated. Protein identification revealed that proteins involved in virulence, adhesion, and resistance were more abundant under biofilm growth conditions. A possible role of the identified proteins in biofilm formation is discussed.

Bacterial Proteins↗

PubMed2006

High prevalence of abnormal acid gastro-oesophageal reflux in idiopathic pulmonary fibrosis.

The aim of this prospective study was to determine the prevalence and characteristics of acid gastro-oesophageal reflux (GER) in patients with idiopathic pulmonary fibrosis (IPF). Sixty-five consecutive patients with well-defined IPF were subjected to 24-h pH monitoring and oesophageal manometry. A total of 133 consecutive patients with intractable asthma and symptoms of GER were used as comparisons. The prevalence of abnormal acid GER in IPF patients was 87%, with 76% and 63% demonstrating abnormal distal and proximal oesophageal acid exposures, respectively. Abnormal acid GER was significantly more common in IPF patients than asthma patients. Only 47% of IPF patients experienced classic GER symptoms. Despite treatment with standard doses of proton pump inhibitors (PPIs), 12 out of 19 patients receiving PPIs during the 24-h pH monitoring had abnormal oesophageal acid exposures by pH probe. There was no correlation between IPF severity and acid GER severity. In conclusion, abnormal acid gastro-oesophageal reflux is highly prevalent, but often clinically occult in patients with idiopathic pulmonary fibrosis. Standard doses of proton pump inhibitors may not suppress the acid gastro-oesophageal reflux in this population. Therefore, further studies are needed to determine if acid abnormal gastro-oesophageal reflux represents an important risk factor for idiopathic pulmonary fibrosis development or progression, and if optimal suppression of acid gastro-oesophageal reflux slows the progression of idiopathic pulmonary fibrosis and/or decreases episodic exacerbations of idiopathic pulmonary fibrosis.

Adult↗

PubMed2005

Dynamics of Saturn's magnetosphere from MIMI during Cassini's orbital insertion.

The Magnetospheric Imaging Instrument (MIMI) onboard the Cassini spacecraft observed the saturnian magnetosphere from January 2004 until Saturn orbit insertion (SOI) on 1 July 2004. The MIMI sensors observed frequent energetic particle activity in interplanetary space for several months before SOI. When the imaging sensor was switched to its energetic neutral atom (ENA) operating mode on 20 February 2004, at approximately 10(3) times Saturn's radius RS (0.43 astronomical units), a weak but persistent signal was observed from the magnetosphere. About 10 days before SOI, the magnetosphere exhibited a day-night asymmetry that varied with an approximately 11-hour periodicity. Once Cassini entered the magnetosphere, in situ measurements showed high concentrations of H+, H2+, O+, OH+, and H2O+ and low concentrations of N+. The radial dependence of ion intensity profiles implies neutral gas densities sufficient to produce high loss rates of trapped ions from the middle and inner magnetosphere. ENA imaging has revealed a radiation belt that resides inward of the D ring and is probably the result of double charge exchange between the main radiation belt and the upper layers of Saturn's exosphere.

Atmosphere↗

PubMed2005

Survivin, Survivin-2B, and Survivin-deItaEx3 expression in medulloblastoma: biologic markers of tumour morphology and clinical outcome.

Survivin is an apoptotic inhibitor that is expressed at high levels in a variety of malignancies. Survivin has four known alternative splice forms (Survivin, Survivin-2B, Survivin-deltaEx3, and Survivin-3B), and the recent literature suggests that these splice variants have unique functions and subcellular localisation patterns. We evaluated 19 fresh-frozen paediatric medulloblastomas for the expression of three Survivin isoforms by quantitative PCR. Survivin was most highly expressed when compared with normal cerebellar tissue. We also investigated Survivin protein expression in 40 paraffin-embedded paediatric medulloblastoma tumours by immunohistochemistry. We found a statistically significant association between the percentage of Survivin-positive cells and histologic subtype, with the large-cell-anaplastic variant expressing Survivin at higher levels than the classic subtype. We also found a statistically significant relationship between the percent of Survivin-positive cells in the tumours and clinical outcome, with higher levels of Survivin correlating with a worse prognosis. In summary, our study demonstrates a role for Survivin as a marker of tumour morphology and clinical outcome in medulloblastoma. Survivin may be a promising future prognostic tool and potential biologic target in this malignancy.

Biomarkers, Tumor↗

PubMed2005

A feasibility study of a personalized, internet-based compliance system for chronic disease management.

This paper describes a feasibility study on an Internet-based compliance system to provide personalized care for patients suffering from chronic diseases. Relevant medical trials from three different European countries provided preliminary evidence of the feasibility of the system and its efficacy in helping patients to manage their diseases at home. The study discusses further improvements not only for the C-Monitor system, but also for other Internet-based health-care services.

Chronic Disease↗

PubMed2005

Importance of evacuatory disturbance in evaluation of faecal incontinence after third degree obstetric tear.

OBJECTIVE: To correlate anorectal function including rectal evacuation with anorectal physiology and endoanal ultrasound in women with third degree obstetric anal sphincter injury repaired at the time of delivery. PATIENTS AND METHODS: Forty-four women with repaired third degree tears underwent anorectal physiology, anal ultrasonography and clinical assessment using the St. Marks incontinence score (0-24). Evacuatory disturbance was assessed by questionnaire. RESULTS: There was a significant correlation between disturbed evacuation and incontinence symptoms (P=0.030). There was also a significant correlation between disturbed evacuation and internal anal sphincter (IAS) injury (P=0.026), but there was no correlation with external anal sphincter (EAS) injury. There was a correlation between disturbed evacuation and low resting anal pressure (P=0.013). Although IAS defects were associated with low anal pressure, only the correlation with Maximum Squeeze Pressure reached statistical significance (P=0.018). CONCLUSION: Women with evacuatory disturbance after repaired third degree tears have a greater level of incontinence than those whose emptying is normal. This association is related to internal sphincter injury and reduced anal sphincter pressures.

Adolescent↗

PubMed2004

Altered neurometabolite development in HIV-infected children: correlation with neuropsychological tests.

BACKGROUND: HIV-infected children have abnormal cerebral metabolites, measured by proton MR spectroscopy ((1)H-MRS), but how these abnormalities relate to brain function is unclear. METHODS: Metabolite concentrations in five brain regions of 20 HIV-infected and 13 control children were measured, and these findings were correlated with age, log(10) plasma viral load, CD4 count, and neuropsychological scores. RESULTS: Compared with control subjects, HIV patients had decreased choline concentration [Cho] in left frontal white matter (LFW) (-12%; p = 0.04); those with high viral load (>5,000 HIV RNA copies/mL) had decreased right basal ganglia (RBG) [Cho] (-15%; p = 0.005), and [Cr] (-13%; p = 0.02). Patients with high viral load also had higher [Cho] in the midfrontal gray matter (MFG) (+25%; p = 0.002) and lower myo-inositol [Ins] in the RBG (-18%; p = 0.04) than patients with low HIV viral load. N-Acetyl aspartate concentration ([NAA]) correlated with age in right frontal white matter (RFW) (r = 0.59, p = 0.04), LFW (r = 0.66, p = 0.02), and right hippocampus (RHIP) (r = 0.69, p = 0.02) only in control subjects. In contrast, [Ins] correlated with age in both RFW and LFW (r = 0.71, p = 0.0006; r = 0.65, p = 0.006) only in the HIV patients. Log(10) plasma viral load correlated positively with [Ins] in RFW (r = 0.54, p = 0.02) and [Cho] in MFG (r = 0.49, p = 0.04). Compared with control subjects, HIV patients had poorer spatial memory (p = 0.045) and delayed spatial memory correlated with [Cho] in RHIP (r = 0.68, p = 0.02). CONCLUSIONS: These data suggest that normal brain development may be affected in children infected with HIV at birth, particularly evidenced by the lack of age-related increases in the neuronal marker [NAA]. Early, aggressive treatment of infants with HIV before development of encephalopathy is warranted.

Adolescent↗

PubMed2004

Consultant nurses in mental health: a discussion of the historical and policy context of the role.

This paper provides a platform for the discussion of the recent development of the nursing leadership role of consultant nurse. It focuses on the implementation of this role in mental health. The discussion is partially informed by evidence from personal reflections from consultant nurses obtained from semistructured interviews undertaken as part of a pilot study aimed at explaining the influences and context of nursing leadership in mental health. The authors believe that more in depth consideration needs to be given to the interpretation and implementation of such professional policy initiatives in to mental health nursing. Further thought also needs to be given to how consultant nurses in mental health can operationalize their expert clinical practice.

Health Policy↗

PubMed2004

Routine examination of the newborn: the EMREN study. Evaluation of an extension of the midwife role including a randomised controlled trial of appropriately trained midwives and paediatric senior house officers.

OBJECTIVES: To assess the implications and cost-effectiveness of extending the role of midwives to include the routine (24-hour) examination of the healthy newborn usually carried out by junior doctors. DESIGN: The study included a prospective randomised controlled trial (RCT) with mother and baby dyads randomised to either senior house officer (SHO) or midwife for the routine examination of the newborn. Midwives and SHOs were also videoed while performing the examinations and the videos were rated by an independent consultant and senior midwife. In addition extensive interviews, surveys, consultations and assessments were carried out. SETTING: A District General Hospital (for the RCT), a London Teaching Hospital, general practices and mothers' homes (for interviews); questionnaires were sent to all maternity units in England (for the National Survey). PARTICIPANTS: A total of 826 mother and baby dyads in a District General Hospital in south-east England. Midwives and SHOs, as well as midwifery managers, paediatric consultants; general practitioners (GPs) and representatives of key organisations. INTERVENTIONS: A routine examination of a newborn baby was carried out at about 24 hours from birth and a further examination for half the babies in each group, at 10-days at home by the community midwife. MAIN OUTCOME MEASURES: Referrals assessed as appropriate and as major or minor by three independent consultants. Problems identified during the first year of life assessed as identifiable at 24 hours. Quality assessment by video against an agreed written proforma. Maternal satisfaction. Opinion of professionals and mothers about aspects of the examination. RESULTS: There was no statistical difference between SHO and midwife examinations in appropriate referral rates to hospital or community or in inappropriate referral rates to hospital. Videoed assessments were assessed as carried out more appropriately by the midwives than by the SHOs. Overall maternal satisfaction was high and higher when a midwife rather than an SHO examined. Few new health problems were identified at the 10-day examination. From the National Survey, it was estimated that about 2% of babies in England are examined by a midwife. If midwives were to examine all babies where there were no complications of birth or antenatal history, there would be savings of about 2 pounds per baby born, equivalent to savings of 1.2 pounds million nationally. Were midwives to examine all babies on normal wards savings would increase to about 4.30 pounds per baby born or 2.5 million pounds nationally. Representatives of the professional bodies were of the opinion that having trained midwives carrying out the examination would be valuable. CONCLUSIONS: All component aspects of the study were consistent in showing benefits or at least no significant barriers to suitably qualified, trained midwives carrying out the examinations. Developing the role of the midwife to include examination of the newborn is likely to result in improved quality of examinations and higher satisfaction from mothers. It would slightly reduce overall health service costs, with some increased resources needed by midwifery departments, and some decrease in resource needs of paediatric departments. There is a need for further research into the value of the examination being carried out at home rather than in hospital; the overall unsatisfactory quality of the examination of the hips; and appropriate inclusion criteria for which babies' midwives should examine.

Adult↗

PubMed2002

Characterization of an enteropathogenic bovine calicivirus representing a potentially new calicivirus genus.

Bovine enteric caliciviruses (BEC) are associated with diarrhea in young calves. The BEC strains detected in Europe form a third genogroup within the genus "Norwalk-like viruses" (NLV) of the family Caliciviridae. In this report, we present sequence, clinical, and histological data characterizing a novel enteropathogenic BEC strain, NB, detected in fecal specimens from calves in the United States. The complete RNA genome of the NB virus is 7,453 bases long and is organized into two open reading frames (ORFs). ORF-1 is 2,210 amino acids long and encodes a large nonstructural polyprotein contiguous with the major capsid protein (VP1), similar to the lagoviruses and "Sapporo-like viruses" (SLV). The conserved calicivirus motifs were identified in the nonstructural proteins. ORF-2 is located at the 3' end of the genome and encodes a small basic protein (VP2) of 225 amino acids. The 5' and 3' untranslated regions are 74 and 67 bases long, respectively. Among caliciviruses, NB virus shows amino acid identities of 14.1 to 22.6% over the entire ORF-1 nonstructural-protein sequence with NLV, SLV, vesivirus, and lagovirus strains, while the overall sequence identity of the complete NB VP-1 with other caliciviruses is low, varying between 14.6 and 26.7%. Phylogenetic analysis of the complete VP1 protein, including strains from all four calicivirus genera, showed the closest grouping of NB virus to be with viruses in the genus Lagovirus, which cause liver infections and systemic hemorrhage in rabbits. In gnotobiotic calves, however, NB virus elicited only diarrhea and intestinal lesions that were most severe in the upper small intestine (duodenum and jejunum), similar to the NLV BEC strains. The tissues of major organs, including the lung, liver, kidney, and spleen, had no visible microscopic lesions.

Animals↗

PubMed2002

Routine examination of the newborn and maternal satisfaction: a randomised controlled trial.

OBJECTIVE: To determine whether the routine examination of the newborn by a midwife compared with a junior paediatrician (SHO) affects maternal satisfaction with this examination. METHODS: Randomised controlled trial: 826 mother and baby pairs in a district general hospital in south east England were randomised to a paediatric SHO or a midwife for the routine newborn examination. Maternal satisfaction with the examination was analysed in relation to intervention group, process, and background variables. RESULTS: Some 81% of mothers reported that they were satisfied or very satisfied with the newborn examination. Mothers assigned to a midwife were more satisfied with the newborn examination (crude odds ratio (OR) 0.54 (95% confidence interval (CI) 0.39 to 0.75), p < 0.001). However, after provision of health education during the examination, continuity of care provided, and history of miscarriage had been controlled for, status of examiner was no longer related to maternal satisfaction (adjusted OR 0.82 (95% CI 0.57-1.20), NS). The discussion of healthcare issues by the examiner (adjusted OR 0.49 (95% CI 0.34 to 0.70), p < 0.001) and continuity of care (adjusted OR 0.43 (95% CI 0.23 to 0.81), p < 0.01) were both related to enhanced satisfaction, and history of miscarriage (adjusted OR 1.61 (1.08 to 2.40), p < 0.05) was associated with lower maternal satisfaction with the newborn examination. Midwives (61%) were more likely than SHOs (33%) to discuss healthcare issues, such as feeding, sleeping, and skin care. CONCLUSIONS: Mothers were more likely to be satisfied with the newborn examination by a midwife than an SHO because midwives were more likely to discuss healthcare issues during the examination and were able to provide continuity of care. However, midwife examinations according to exclusion criteria agreed with trial midwives excluded half of all newborns, and criteria may have to be reconsidered for practice implementation.

Clinical Competence↗

PubMed2001

Complexities in the neurotoxic actions of 6-hydroxydopamine in relation to the cytoprotective properties of taurine.

The neurotoxin 6-hydroxydopamine was shown to cause an imbalance between the direct and indirect pathways of the striato-nigral system as evidenced by a decreased release of gamma-aminobutyric acid and taurine in the substantia nigra but not in the globus pallidus following neostriatal stimulation with kainate (100 microM). The neurotoxicity of 6-hydroxydopamine is generally believed to result from reactive-oxygen radical formation, although it is also known to inhibit mitochondrial NADH dehydrogenase. The release of Fe(II) from the unactivated form [3Fe(III)-4S] of cytoplasmic aconitase (EC(50) < 8 microM) was shown to be followed by the slower oxidation of thiol groups in the protein. Complete loss of -SH groups, and enzyme activity, was seen after incubation of glyceraldenyde-3-phosphate dehydrogenase with 200 microM 6-hydroxydopamine for 75 min at 37 degrees C (IC(50) = 70.8 +/- 0.3 microM). Thus the cellular effects of 6-hydroxydopamine are complex, involving impairment of mitochondrial function, iron- release, sulphydryl-group oxidation, and enzyme inhibition in addition to direct generation of reactive oxygen radicals. Taurine, which is known to be neuroprotective in some other systems, only affords protection against some of these effects, thereby explaining its reported ineffectiveness against 6-hydroxydopamine toxicity.

Aconitate Hydratase↗

PubMed2001

Methodological issues in the development of a national database for primary care groups and trusts.

At the National Primary Care Research and Development Centre (NPCRDC) we have constructed a national database for all primary care groups (PCGs) in England. At its core, the database links information about population socio-economic and demographic characteristics to generic health status and to the organisation, resourcing and activities of general practice. In this paper we describe and discuss the problems with linking these data, and with defining the boundaries and the local populations of PCGs, given that they have been established on the basis of administrative expediency rather than geographical coherence. We then consider the implications of these difficulties for needs assessment in primary care groups.

Database Management Systems↗

PubMed2001

Feasibility and initial results of an Internet-based pacemaker and ICD pulse generator and lead registry.

The medical community has no independent source of timely information regarding the performance of pacemaker and ICD pulse generators and leads. Accordingly, the authors established an Internet-based registry of pacemaker and ICD pulse generator and lead failures (www.pacerandicregistry.com). During the first year, they found three previously unreported device problems that were promptly communicated to the participants. Of the failures reported, 11% of ICD and 10% of pacemaker pulse generator failures were heralded by signs other than the expected elective replacement indicator (ERI). Average ICD battery longevity was 4.0 +/- 0.7 years, and average dual chamber pacemaker battery longevity was 6.8 +/- 2.6 years. Disrupted insulation accounted for 54% of pacemaker and 29% of ICD lead failures. Compared to pacemaker pulse generator and lead failure, ICD device failures were more likely to cause severe clinical consequences. In conclusion, an Internet-based registry is feasible and capable of providing timely data regarding the signs, causes, and clinical consequences of pacemaker and ICD failures.

Canada↗

PubMed2001

A pilot study of the technical quality of telemedical consultations for remote trauma management.

The technical performance of a telemedical system when used for remote trauma management was compared with face-to-face consultation. Two rooms, 20 yards apart, were linked telemedically in the same Accident & Emergency Department. Two hundred patients, with 'minor' and 'moderate' injuries, underwent the two types of consultation. The Accident & Emergency consultant marked physical parameters using a five-point pre-determined Likert scale. The following parameters were thought to be of excellent quality when compared to face-to-face consultation: overhead fluorescent lighting for the background illumination, video lighting for a close-up view, sound quality after volume adjustment, echo-cancellation after adjustment and lip synchronization. However, the following parameters scored poorly: sound before volume adjustment, echo-cancellation before adjustment, fine and coarse movements. It can be concluded that the quality of lighting and image quality are good in telemedicine. Sound and movement still present some problems. This technology is likely to be used more frequently for remote trauma management.

Humans↗

PubMed2001

A randomized controlled trial to assess the psychological impact of a family history screening questionnaire in general practice.

BACKGROUND: It has been postulated that systematic enquiry about patients' family histories of inherited illnesses would lead to a population of 'worried well'. OBJECTIVE: The purpose of the present study was to evaluate if the use of a family history screening questionnaire (FHSQ) as part of a general practice health check leads to psychological distress. METHOD: We conducted a randomized controlled trial of a self-administered FHSQ in a single general practice. Individuals who had not had a health check within the previous 2 years were randomized within three age group strata to intervention group (receiving health check and FHSQ) or control group (only receiving health check). A total of 156 patients were offered health checks; 100 accepted and 76 of them were followed through to the 3-month end point. Responses to the six-item Spielberger State-Trait Anxiety Inventory (STAI), Perception of Health questionnaire and Family History Concern questionnaire were compared between intervention and control groups. RESULTS: A two-way analysis of variance on the STAI scores 1 and 2 weeks after the health check with baseline scores as a covariate showed that at both times anxiety was higher in the intervention group than in the controls (F = 6.4; d.f. = 1,73; P = 0.014). Three months later, there was no significant difference between the two groups. The Perception of Health questionnaire only showed a significant result at 1 week, the intervention group having a more pessimistic response to the question eliciting patient's concerns about future health (P = 0.025). CONCLUSION: Short-term psychological distress due to the family history screening questionnaire was identified but did not persist.

Adult↗