Search PubMed⌕ Search

Biomedical subjects

H Williams

Publications and source records attributed to H Williams.

At least 91 records · Page 5Linked to original sources
PubMed1998

Hepatitis G virus infection in drug users in Liverpool.

OBJECTIVES: To establish the prevalence of hepatitis G (HGV) in drug users in Liverpool; to explore the risk factors for, and the effects of, HGV infection. METHODS: Serum samples from 129 drug users who had attended the Infectious Diseases Unit at Fazakerley Hospital, Liverpool, between January 1995 and June 1996 were examined for HGV RNA using PCR, HGV RNA results were collated with demographic data, information on drug-use behaviour, hepatitis B (HBV) and C (HCV) serology, and the results of serum bilirubin and aspartate amino-transferase (AST) measurements. RESULTS: Overall, 37 (29%) of patients were HGV RNA positive, 89 (69%) were negative, and equivocal results were obtained in three (2%) cases. Direct sequencing of PCR products of the 5' non-translated region for 13 patients showed that these were generally more closely related to the HGV than the GB virus C (GBV-C) sequence. HGV co-infection with HCV and HBV was common: of HGV-positive patients, 28 (76%) and 16 (44%) had antibodies to HCV (anti-HCV) and hepatitis B core protein (anti-HBc), respectively. Increasing duration of injecting drug use was associated with a decreasing seroprevalence of HGV RNA, dropping from 39% for 0-4 years of injecting to 14% for > 12 years injecting. Serum bilirubin and AST values were frequently elevated, but statistical analysis showed no differences between HGV-positive and HGV-negative patient groups. CONCLUSIONS: HGV infection is common in drug users in Liverpool, but HGV RNA prevalence falls with increasing duration of injecting drug use, probably as a result of viral clearance and the development of protective immunity. HGV infection does not appear to be a significant cause of hepatic dysfunction in Liverpool drug users.

Adult↗
PubMed1998

Community validation of the United Kingdom diagnostic criteria for atopic dermatitis in Romanian schoolchildren.

Although the U.K. modification of Hanifin and Rajka's diagnostic criteria for atopic dermatitis (AD) for use in epidemiological studies has demonstrated good validity and repeatability when previously tested in a U.K. community setting, little is known about its performance in other countries where different cultural, educational and linguistic factors could impair validity. We used a questionnaire to test the validity of the U.K. criteria as a point prevalence measure of AD in 1114 Romanian schoolchildren aged 6-12 years against the clinical diagnosis of a dermatologist with an interest in AD, who was unaware of the questionnaire content and responses. The sensitivity and specificity of the U.K. criteria for AD in this setting was 74% and 99%, respectively, an improvement rather than a deterioration in validity when compared with the previous U.K. study. Test-retest repeatability for all of the questions pertaining to the U.K. criteria using the chance-corrected kappa statistic was high, with values of 0.72 and over. The positive predictive value of the criteria was lower than in the U.K. study (63% compared with 80%, respectively) due to the very low prevalence of AD in this study (2.4%). The validity of a parental report of 'eczema' was poor, with a sensitivity of 22%, specificity of 97% and positive predictive value of 18%. This study suggests that the U.K. criteria perform well in settings outside the U.K., although care has to be taken when using the criteria to ascertain cases in settings where the prevalence of AD is very low.

Child↗
PubMed1998

Diogenes' syndrome in patients with intellectual disability: 'a rose by any other name'?

Diogenes' syndrome is characterized by marked self-neglect, domestic squalor, social withdrawal and hoarding of rubbish (syllogomania). The syndrome has been reported to occur in association with a wide variety of conditions, but the present authors were unable to find any previous reports of Diogenes' syndrome in patients with intellectual disability.

Activities of Daily Living↗
PubMed1998

Cellular immunity to varicella-zoster virus in patients with major depression.

The incidence of herpes zoster increases markedly with advancing age, and this appears to be causally related to an age-dependent decline in varicella-zoster virus (VZV)-specific cellular immunity. Psychologic stress has also been linked to the occurrence of herpes zoster, but the mechanism involved has not been investigated. This study examined the relationship between major depression and VZV-specific cellular immunity by comparing VZV-specific responder cell frequency (RCF) in adults with major depression (n = 11) to that in age- and sex-matched nondepressed controls (n = 11) and in a larger group of nondepressed adults who were > or = 60 years old. VZV-specific RCF in depressed patients was markedly reduced compared with the RCF in matched controls (t = 2.7, P < .02). In fact, the levels of VZV-specific RCF in the depressed patients were comparable in magnitude to the low levels found in adults > or = 60 years of age. These data indicate that major depression is associated with a marked decline in VZV-specific cellular immunity.

Adult↗
PubMed1998

Use of laboratory assays to predict cytomegalovirus disease in renal transplant recipients.

Eight laboratory assays, viz., the pp65 direct antigenemia test, a quantitative cytomegalovirus (CMV)-specific immunoglobulin G (IgG) assay (Biomerieux VIDAS), a CMV-specific IgM assay (Biomerieux VIDAS), the Hybrid Capture system (Murex), an in-house PCR with plasma (P-PCR) and leukocytes (L-PCR), and a commercial PCR (Roche AMPLICOR) with plasma (P-AMP) and leukocytes (L-AMP), were compared for their abilities to predict CMV disease before the onset of illness in a prospective study of 37 renal transplant recipients. By using an expanded criterion for active infection (two or more of the markers positive) and a clinical definition of disease, 22 (59%) patients were identified as having active CMV infection and 13 (35%) were identified as having CMV disease. Of the 13 CMV-seronegative recipients who received seropositive kidneys (R- group), 8 had active infection and disease. All assays were 100% specific and 100% predictive of CMV disease in the R- group. The leukocyte PCRs (L-PCR and L-AMP) were the most sensitive assays, had positive results an average of between 8 and 13 days before the onset of illness, and were the assays of choice. The performance of the assays was less satisfactory for the 24 patients who were CMV seropositive before transplantation (R+ group). A negative result was more useful for this group. Overall, P-AMP had the best results, and it could be the assay of choice for monitoring R+ patients. The non-PCR-based methods generally had high specificities but often gave late positive results and were not sensitive enough for use as prediction tools for either group of patients.

Antibodies, Viral↗
PubMed1998

"Saturday night fever": ecstasy related problems in a London accident and emergency department.

OBJECTIVES: To report on the extent and nature of acute MDMA (ecstasy) related problems presenting to a large London hospital's accident and emergency (A&E) department. METHOD: The computerised attendance records for all patients attending the A&E department over a 15 month period were retrospectively screened. Potential cases thus identified had their case notes systematically reviewed to confirm the history of MDMA use and to extract other relevant data. RESULTS: Forty eight consecutive MDMA related cases were identified. All were in the 15-30 year age group with the majority presenting in the early hours at weekends and having consumed the drug at a night club. The mean number of tablets consumed was two and almost 40% had taken MDMA before. Polydrug use was common with half of the sample having concurrently taken another illicit substance--most commonly other stimulants (amphetamines and cocaine). A wide range of adverse clinical features was found. The most common symptoms were vague and non-specific such as feeling strange or unwell, however many patients had collapsed or lost consciousness. The most common signs elicited were related to sympathetic overactivity, agitation/disturbed behaviour, and increased temperature. The more serious complications of delirium, seizures, and profound unconsciousness (coma) were commoner when MDMA was used in combination with other substances. CONCLUSIONS: For young adults presenting late at night at weekends and exhibiting symptoms of sympathetic overactivity, disturbed behaviour, and increased temperature ("Saturday night fever") the use of stimulant dance drugs especially MDMA should be suspected. As MDMA use does not appear to occur in isolation, the clinical picture is likely to be complicated by multiple rather than single drug ingestion. This poses increased diagnostic and management challenges for A&E staff who typically represent the front line response to dance drug related problems.

Adolescent↗
PubMed1998

The butyrylcholinesterase K variant and susceptibility to Alzheimer's disease.

Previous work has shown an association between the K variant of the butyrylcholinesterase (BCHE) gene and Alzheimer's disease (AD) in patients carrying the epsilon4 allele of ApoE. We attempted to replicate this finding in 181 UK white AD cases and 71 controls. No difference was found in BCHE-K genotypes (p=0.75) or alleles (p=0.70) between patients and controls. Moreover, despite a significant excess of ApoE epsilon4 in patients versus controls (p<0.0001), we found no evidence to support previous reports of an interaction between ApoE and BCHE-K (chi2=1.49, df=4, p=0.83).

Aged↗
PubMed1998

Anesthetic techniques and positioning: implications for perioperative nurses.

Depending on the anesthetic technique used and the position in which the patient is placed, the perioperative nurse knowledgeable in the implications of each technique will positively impact patient safety and management. This involves a thorough understanding of the systems affected and associated risks. Whether general anesthesia, regional anesthesia, or monitored anesthesia care is provided, specific actions by the nurse facilitates teamwork.

Anesthesia↗
PubMed1998

Effect of genotypes on the quantification of hepatitis C virus (HCV) RNA in clinical samples using the Amplicor HCV Monitor Test and the Quantiplex HCV RNA 2.0 assay (bDNA).

The Amplicor HCV Monitor test and the Quantiplex HCV RNA 2.0 (bDNA) assay are two commercially available assays for the quantification of hepatitis C virus (HCV) RNA in clinical samples. A direct comparison of the two assays was carried out using sera frozen previously from patients known to be chronically infected with HCV. Overall, 61 samples from 51 patients were tested simultaneously by the two methods: 67% (28/42) of the patients were infected by HCV genotype/serotype 1, 10% (4/42) with type 2, and 24% (10/42) with type 3. When the absolute value from each assay was examined, the Quantiplex assay gave a consistently higher reading and the mean logarithmic difference between the two assays was 1.4 (1.0 in type 1, 2.0 in type 2, and 2.2 in type 3). When analyzed according to genotype, strong correlation was observed between the two assays for type 1 (r = 0.83, 95% CI 0.63-0.93, P < 0.01), but not for nontype 1 samples. Despite the difference in absolute level reported by the two assays, there was a consistent trend of change in HCV RNA concentration by both assays in patients whose consecutive samples were analyzed and the differences between the two assays in consecutive samples were within 0.4 log of each other. The results suggested that with samples containing genotype 1, the Amplicor assay was more sensitive than the Quantiplex assay by about one log. However, the sensitivities of the two assays with nontype 1 samples were much closer probably due to the failure of the Amplicor assay to quantify nontype 1 genotypes effectively.

Adolescent↗
PubMed1998

Allergic rhinitis history as a predictor of other future disqualifying otorhinolaryngological defects.

BACKGROUND: Problems with the otorhinolaryngological system represent the largest category of pilot referrals for specialist assessment and possible waiver recommendation in the U.S. Navy. Most of these referrals deal with allergic rhinitis (AR). Approximately 3% of all Naval aircrew have a waiver for AR. This paper tests the hypothesis that the identification of a history of AR is a predictor for the development of future disqualifying otorhinolaryngological (ear, nose, and throat, or ENT) diseases such as chronic sinusitis, alternobaric disease, conductive hearing loss, or the need for various surgical procedures (i.e., Caldwell Luc antrostomy, myringotomy, polypectomy, mastoidectomy, and functional endoscopic sinus surgery. METHODS: The U.S. Navy Aviation Medical Data Retrieval System (AMDRS) was searched for aircrew who were diagnosed only with AR in 1988. These aircrew were matched with a control group from the 1988 database who had no diagnoses of AR or any of the other disqualifying ENT diseases. The AR cohort and controls had their physical examinations up to 1995 assessed to see if any of the disqualifying ENT conditions had developed. RESULTS: There was a statistically significant increase in the number of identifiable chronic sinusitis cases but there was no significant relationship between an AR history and the development of any of the other ENT disease categories. CONCLUSION: Based on the study findings, it is doubtful that uncomplicated AR as an isolated historical diagnosis should be disqualifying for either candidate or designated aircrew.

Aerospace Medicine↗
PubMed1997

Feasibility and effects of nurse run clinics for patients with epilepsy in general practice: randomised controlled trial. Epilepsy Care Evaluation Group.

OBJECTIVE: To test the feasibility and effect of nurse run epilepsy clinics in primary care. DESIGN: A randomised controlled trial of nurse run clinics versus "usual care." SETTING: Six general practices in the South Thames region. SUBJECTS: 251 patients aged over 15 years who were taking anti-epileptic drugs or had a diagnosis of epilepsy and an attack in the past two years who met specified inclusion criteria and had responded to a questionnaire. MAIN OUTCOME MEASURES: Questionnaire responses and recording of key variables extracted from the clinical records before and after the intervention. RESULTS: 127 patients were randomised to a nurse run clinic, of whom 106 (83%) attended. The nurse wrote 28 letters to the general practitioners suggesting changes in epilepsy management. For this intervention group compared with the usual care group there was a highly significant improvement in the level of advice recorded as having been given on drug compliance, adverse drug effects, driving, alcohol intake, and self help groups. CONCLUSIONS: Nurse run clinics for patients with epilepsy were feasible and well attended. Such clinics can significantly improve the level of advice and drug management recorded.

Anticonvulsants↗
PubMed1997

Epstein-Barr virus induced virus-associated hemophagocytic syndrome and monoclonal TCR-beta rearrangement: a case report.

Virus-associated hemophagocytic syndrome (VAHS) is a rare histiocytic proliferative disorder secondary to viral infection affecting children and young adults and in which there is both a poor prognosis and no specific treatment. We report a case of VAHS in a 22-year-old woman secondary to infection with Epstein Barr virus in which multiorgan failure developed with a fatal outcome 3 weeks after presentation. Clonal analysis showed EBV incorporation into the T cell genome accompanied by monoclonal rearrangement of the TCR beta gene. Treatment with cyclosporin A resulted in hematological improvement but the patient died of disseminated fungal infection. We propose that bone marrow ablation and allografting should be available for these rare cases and suggest that a protocol should be developed with designated transplant centres to aid early referral.

Adult↗
PubMed1997

Instar susceptibility of the monarch butterfly (Danaus plexippus) to the neogregarine parasite, Ophryocystis elektroscirrha.

The susceptibility of the monarch butterfly (Danaus plexippus) larvae to the neogregarine parasite, Ophryocystis elektroscirrha, was tested in the laboratory. Spore loads recovered from infected monarch butterflies were directly related to the inoculum level, larval stage of the host, and spore age. There was a linear relationship between spores ingested by first instar larvae and spore concentration. Larvae feeding on leaves treated with 0, 50, 500, 5000, or 50,000 spores averaged 0, 0, 193, 457, or 1,255 spores, respectively, on the abdomens of the adult butterflies. When first, third, and fifth instar larvae were given 14.5 spores/mg of body weight, there was no significant difference in the spore load of the adults resulting from the first and third instars. However, there were significant differences in the spore load from adults resulting from the first and third instars versus the fifth instar. In addition, 1-year-old spores were not as infectious as fresh spores. Our findings indicate that under field conditions, the first instar is most likely to become infected because one spore appears sufficient to produce a detectable spore load in the adult. Older instars are less susceptible and have fewer opportunities to encounter sufficient viable spores for infection to occur. Thus, vertical transmission appears to be the primary mode of parasite maintenance in natural populations of monarch butterflies.

Animals↗
PubMed1997

Consensus chemistry and beta-turn conformation of the active core of the insect kinin neuropeptide family.

BACKGROUND: Neuropeptides are examples of small, flexible molecules that bind to receptors and induce signal transduction, thereby eliciting biological activity. The multifunctional insect kinin neuropeptides retain full activity when reduced to only their carboxy-terminal pentapeptide (Phe1-X2-X3-Trp4-Gly5-NH2), thereby allowing extensive structure-function studies and conformational analysis. RESULTS: A combined experimental and theoretical analysis of the insect kinin carboxy-terminal pentapeptide was used to probe the role of each residue, define the bioactive conformation, and design a constrained bioactive analog. Coupling receptor-binding data with two biological activity assays allowed receptor binding and signal transduction to be differentiated. A preferred beta-turn conformation, found for residues 1-4 by molecular dynamics simulations, was tested by designing a conformationally restricted cyclic hexapeptide. This cyclic analog showed a preference for the beta-turn conformation, as shown by a conformational search and nuclear magnetic resonance spectroscopy, and it showed stronger receptor binding but decreased activity relative to highly active linear analogs. CONCLUSIONS: Each residue of the insect kinin carboxy-terminal pentapeptide has a distinct role in conformational preference, specific receptor interactions or signal transduction. The beta-turn preference of residues Phe1-X2-X3-Trp4 implicates this as the bioactive conformation. The amidated carboxyl terminus, required for activity in many neuropeptide families, may be generally important for signal transduction and its inclusion may therefore be essential for agonist design.

Animals↗
PubMed1997

Hepatitis G virus RNA and its relation to hepatitis C infection in adult haemophilic patients.

The prevalence of hepatitis C virus (HCV) infection and hepatitis G virus (HGV) RNA were studied in 50 adult haemophilic patients who had received commercial clotting factors prior to 1980. HGV RNA was detectable in 6/ 50 patients (12%); 49/50 (98%) had antibody to HCV and 40/49 (82%) of these were viraemic with detectable HCV RNA; 5/6 patients with detectable HGV RNA had co-existing HCV infection and viraemia. The HGV PCR products from all six patients were directly sequenced and all were shown to be similar to that of HGV but more diverse from that of GB virus C. One patient who had persistent abnormal liver function tests had detectable HGV RNA but no evidence of hepatitis B or C. The presence of HGV RNA in the absence of hepatitis B and C infection indicates that this virus is capable of independent transmission. Independent response to interferon was demonstrated in one patient with co-infection who lost HGV but not HCV after interferon therapy.

Adolescent↗