Search PubMed⌕ Search

Biomedical subjects

S Wood

Publications and source records attributed to S Wood.

At least 91 records · Page 5Linked to original sources
PubMed1997

Postoperative infection following clean facial surgery.

Postoperative facial wound infection and breakdown adds to patient morbidity and compromises the cosmetic outcome. This prospective study of 351 patients with a total of 464 wounds for clean elective facial surgery assessed three significant risk factors for wound infection: operative site, oncological surgery, and complex surgery. The findings demonstrated a significantly higher infection rate for the nasal and auricular zones compared with the rest of the face. Wound infection rates were 6.5% for the nasal area, 5% for the auricular area, and 1.5% for the rest of the face. The higher risk of infection to these zones was found to be independent of the lesion excised (benign vs. malignant) and the complexity of the surgery performed. Oncological surgery (skin cancer) and complex surgery (skin grafts and local flaps) were found to increase the risk of postoperative infection significantly by up to fifteenfold compared with nononcological operations with direct closure. The associated morbidity and compromised cosmetic results with facial surgical wound breakdown makes it important to identify these higher risk factors and consider added prophylaxis.

Adolescent↗
PubMed1997

Field sensitivity of targeted neonatal hearing screening by transient-evoked otoacoustic emissions.

OBJECTIVE: Population ascertainment of children having bilateral moderate to profound hearing impairment was undertaken to find out how many had passed (false negatives) and how many had failed (true negatives) a neonatal screening test based on transient-evoked otoacoustic emissions (TEOAE). DESIGN: Neonatal screening using a purpose-built TEOAE instrument was undertaken in neonates, at eight hospitals in districts distributed around the United Kingdom starting in 1988. Screening was targeted on neonates at risk of hearing impairment. A total of 7500 babies had been tested by the end of 1995. Searching of audiological records in the districts completed at the end of 1995 ascertained 218 children born between January 1988 and December 1993 who had hearing threshold levels in both ears of 50 dB or more, averaged over the speech frequencies 0.5, 1, 2, and 4 kHz. Of those, 47 had completed the neonatal TEOAE screening test. Retrospective examination of their TEOAE records indicated whether they had passed or failed the screening test. RESULTS: Eleven of the 47 had passed the screening test, although two of those had documented acquired hearing impairment occurring after screening. Disregarding those two cases leaves nine false negatives out of 45, giving a sensitivity estimate of 80% (36 divided by 45). In two of the nine cases, there was documented evidence of progression, one of whom had a family history of progressive hearing loss. CONCLUSIONS: Targeted neonatal hearing screening programs based on TEOAE can expect to identify hearing impairment in approximately 80% of babies screened. The cause of false negatives is a matter for conjecture. There may be several reasons: the test may give an incorrect result, there may be a later acquired hearing impairment, or there may be a progressive hearing loss of unknown origin. Passing a neonatal screening test is not a valid reason to forego further surveillance, or to disregard parental suspicion of hearing impairment.

Acoustic Stimulation↗
PubMed1997

A 2.8 megabase YAC contig spanning D8S339, which is tightly linked to the Werner syndrome locus.

A number of gene loci, including the locus for Werner syndrome (WRN), map to proximal human chromosome 8p near the genetic marker D8S339. In this report, we present a long range physical map of an approximately 2.8 megabase yeast artificial chromosome contig centred on D8S339. In this map, we localize the WRN-linked polymorphic sequence-tagged sites (STS) D8S339 and D8S1055, as well as a novel polymorphic STS, D8S2297. We also refine the positions of three known gene loci, GTF2E2, GSR, and PPP2CB, relative to the location of WRN within the map.

Cell Line↗
PubMed1997

Changing performance of the Health Visitor Distraction Test when targeted neonatal screening is introduced into a health district.

The change in the performance of the HVDT as targeted neonatal hearing screening has been introduced has been examined for the Nottingham district. The records for all children born in the period 1984-1993 within the district and having a permanent hearing loss of > or = 50 dB in the better ear have been examined. The referral route leading to ascertainment of the hearing loss as well as the result of any screening tests were noted. The data shows an increase in the number referred prior to the HVDT, mainly as a result of neonatal screen failure. At the same time there has been a reduction in the sensitivity of the HVDT from 78% in the first half of the decade to 38% for the second half. There are also some indications of an increase in the coverage and the failure rate over the time. Possible reasons for these changes are discussed.

Evoked Potentials, Auditory, Brain Stem↗
PubMed1997

Adaptive and maladaptive utilization of color cues by patients with mild to moderate Alzheimer's disease.

The ability to utilize color information was investigated in 12 patients with mild to moderate probable Alzheimer's Disease (DAT) and in 12 age- and gender-matched control subjects. All subjects underwent testing of visual acuity and color vision before being tested with a cognitive task consisting of four conditions (no color, color as attention enhancer, color as valid cue, color as distracter). Although the groups did not differ in visual acuity or color vision, patients with DAT were less accurate than controls in all four conditions of the cognitive task. Both groups performed best with color as a valid cue and worst with color as distracter, but condition had a significantly stronger effect on patients than on controls. It is concluded that color is a potent stimulus attribute for patients with DAT.

Journal Article↗
PubMed1996

Region-specific reduction in stress-induced c-fos mRNA expression during pregnancy and lactation.

Hypothalamo-pituitary-adrenal (HPA) responses to stress are dramatically attenuated during lactation. To examine whether this is due to diminished stress-induced activation of specific areas of the brain involved in HPA responses, c-fos mRNA expression was employed as a marker of stress-induced neuronal activation. Regional levels of expression were quantified in female rats exposed to 30 min immobilisation stress during late pregnancy (days 19-21), early lactation (days 3-4) and mid-lactation (days 10-14), and compared with the levels in virgin females. Stress-induced levels of corticosterone were significantly lower in late pregnant and early lactating rats compared with the levels in virgin females, and this correlated with a marked attenuation of stress-induced c-fos mRNA expression in the parvocellular division of the PVN. This reduced activation suggests that neuroendocrine hyporesponsiveness during lactation may arise from an effect on afferent pathways to the PVN. Extrahypothalamic areas known to be important for HPA activation displayed three patterns of c-fos mRNA expression: (i) in the ventral tegmental area, dorsal vagal complex, pyriform cortex and all areas of the hippocampus (CA1, CA2, CA3, dentate gyrus), expression levels did not vary significantly with reproductive status; (ii) in the locus coeruleus (A6 catecholaminergic group), a peak of expression was detected in late pregnant animals; and (iii) in the medial amygdala, ventral part of the lateral septum and cingulate cortex expression was significantly reduced in pregnant and lactating animals, with a nadir in early lactation. The decreased expression of c-fos mRNA in these latter areas correlated with that in the parvocellular PVN, and suggests that their interaction may contribute to the reduced neuroendocrine responses of lactating rats.

Animals↗
PubMed1996

Localization of a gene for a glutamate binding subunit of a NMDA receptor (GRINA) to 8q24.

A glutamate binding subunit gene, GRINA, has been previously mapped to human chromosome 8. A form of inherited epilepsy, benign familial neonatal convulsions (BFNC), has also been localized to chromosome 8. As NMDA receptors have been implicated in the pathogenesis of epilepsy, we were interested in determining whether GRINA mapped to the same region of chromosome 8 as BFNC. Fluorescence in situ hybridization localized GRINA to band 8q24, distal to the thyroglobulin gene. The strongest signal was seen at 8q24.3. A panel of 97 radiation hybrids (RH) was used to verify the localization. The RH mapping results placed GRINA as the most telomeric marker on our map of 8q24, distal to the interval defined for BFNC.

Animals↗
PubMed1996

Trunk muscle parameters determined from MRI for lean to obese males.

Transverse magnetic resonance images at the L(4)-L(5) level of 26 males ranging in body mass index from 19.7 to 39.5 were digitized using a computer video monitor with mouse-mediated digitization software. The digitized musculature included the right and left psoas, rectus, abdominis, quadratus lumborum, oblique, and paraspinal muscle groups. From the digitized profiles, cross-sectional areas, and anteroposterior and mediolateral moments from the vertebral centroid were subsequently calculated. Multiple regression formulae were derived to predict the muscle parameters from the most strongly related anthropometrics. Cross-sectional area and moment arms for lean and obese groups were also compared. Significant regression formulae were derived for the cross-sectional area of the rectus abdominis and obliques, for mediolateral moment arms of the paraspinals, psoas, and obliques, and for anteroposterior moments of all four muscles. Comparison of muscle parameters for lean and obese subjects revealed minimal differences, though normalization of muscle cross-sectional areas by trunk area produced values which were statistically smaller for all muscles of the obese relative to lean subjects. RELEVANCE:--Identifying variations in trunk muscular geometry across specific population groups will assist in further refining the existing morphometric data base used to estimate the forces experienced about the lower back. By identifying these variations, it may be possible to observe factors which may predispose a specific population to low back pain.

Journal Article↗
PubMed1996

Hepatic stellate cell activation occurs in the absence of hepatitis in alcoholic liver disease and correlates with the severity of steatosis.

BACKGROUND/AIMS: There is now overwhelming evidence that hepatic stellate cells are the principal cells involved in hepatic fibrogenesis. In several different forms of liver injury it has been demonstrated that they proliferate and undergo phenotypic transformation (activation) into matrix-producing, myofibroblast-like cells in response to necroinflammation, mediated in part, by Kupffer cell-derived factors. In alcoholic liver disease, however, the observation that fibrosis can occur in the absence of alcoholic hepatitis has cast doubt on necroinflammation being an absolute pre-requisite for alcohol-related hepatic stellate cells proliferation/activation and subsequent fibrogenesis. METHODS: Evidence for hepatic stellate cells activation has been sought in liver biopsies from 38 well-documented alcoholic patients with no evidence of alcoholic hepatitis or cirrhosis and eight normal controls. Activated hepatic stellate cells were identified immunohistochemically using a specific monoclonal antibody to detect cytoplasmic alpha smooth muscle actin (alpha-SMA), which is not present in quiescent cells. Kupffer cells were detected with the monoclonal antibody KP1 and collagen was stained using Sirius red. Immunoreactive cells and the amount of fibrosis were quantified, using a Kontron Vidas Image Analyser. Steatosis was graded from 0 (none-few hepatocytes containing fat) to 3 (> 2/3 hepatocyte containing fat). RESULTS: Biopsies from alcoholic patients contained significantly greater numbers of activated hepatic stellate cells (alpha-SMA+ve) than control biopsies (average cell counts: 84 +/- 11/mm2 versus 23 +/- 5/mm2, p < 0.0001). There was no correlation between numbers of activated hepatic stellate cells and either numbers of Kupffer cells or amount of fibrosis. There was, however, a significant correlation between hepatic stellate cells activation and steatosis (grade 0, 15 +/- 7 cells/unit area (n = 4), grade 1, 56 +/- 16 (n = 13), grade 2, 85 +/- 20 (n = 9), grade 3, 137 +/- 19 (n = 12); p = 0.002, ANOVA). CONCLUSIONS: These results suggest that neither necroinflammation nor an increase in Kupffer cells is an absolute prerequisite for hepatic stellate cells proliferation/activation and subsequent fibrogenesis in alcoholic liver disease. The correlation between alcohol-induced hepatic stellate cells activation and severity of steatosis is likely to reflect that both are attributable in part to the metabolic consequences of ethanol metabolism, namely increased concentrations of acetaldehyde and lipid peroxidation.

Analysis of Variance↗
PubMed1996

Home parenteral nutrition in adults: a multicentre survey in Europe in 1993.

A retrospective survey was performed in 1994, involving 496 adult home parenteral nutrition (HPN) cases, newly enrolled in the year 1993 from 13 European countries from 75 centres. From the 8 countries having registered more than 80% of cases (423 patients), incidence and prevalence ranged from 0.2 to 4.6 and 0.3 to 12.2 patients/10(6) population/year. In the patients studied, the diagnosis was cancer (42%), Crohn's disease (15%), vascular diseases (13%), radiation enteritis (8%), AIDS (4%) and other nonmalignant non-AIDS diseases (18%). Short bowel syndrome and intestinal obstruction were the two major indications for HPN in 31% and 22%, respectively. Seventy-three percent of the centres had a nutrition team. HPN was administered through a tunnelled venous central catheter in 73%, cyclical nocturnal infusions were used in 90% of patients, and intravenous feeding was the sole source of nutrition in 33%. Only 44% undertook HPN unaided. The present report indicates that cancer has now become the main indication for HPN in Europe; there was, however, a heterogeneous distribution of diseases amongst the reporting countries. The observed 9 (6-12)-month probability of survival was poor in AIDS (n = 8; 12%) and cancer patients (n = 78; 29%) but better for the other HPN indications (n = 115; 92%).

Journal Article↗
PubMed1996

Actual versus self-reported cognitive dysfunction in HIV-1 infection: memory-metamemory dissociations.

The relationship between subjective awareness and objective neuropsychological status in HIV-1 infection remains unclear. Forty-six HIV-1 seropositive males were administered a battery of neuropsychological measures assessing episodic memory, metacognition, and depression. Results of ANOVA revealed a dissociation between subjects' self-complaint of neuropsychological impairment and objective performance, with subjects who denied cognitive impairment performing worse on memory testing. Three subgroups were identified: A group whose self-reported cognitive impairment exceeded deficits demonstrated on memory testing (37% of subjects); a group who denied impairment but evidenced deficits on memory testing (26% of subjects); and a group whose self-appraisal was consistent with performance (37% of subjects). These data suggest that self-report of cognitive dysfunction among HIV-1 infected subjects is frequently at variance with objective neuropsychological testing and that diminished awareness of decline among medically symptomatic HIV-1 infected subjects can be identified.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Engineering the C-region of human insulin-like growth factor-1: implications for receptor binding.

Recombinant wild-type human IGF-1 and a C-region mutant in which residues 28-37 have been replaced by a 4-glycine bridge (4-Gly IGF-1) were secreted and purified from yeast. An IGF-1 analogue in which residues 29-41 of the C-region have been deleted (mini IGF-1) was created by site-directed mutagenesis and also expressed. All three proteins adopted the insulin-fold as determined by circular dichroism. The significantly raised expression levels of mini IGF-1 allowed the recording of two-dimensional NMR spectra. The affinity of 4-Gly IGF-1 for the IGF-1 receptor was approximately 100-fold lower than that of wild-type IGF-1 and the affinity for the insulin receptor was approximately 10-fold lower. Mini IGF-1 showed no affinity for either receptor. Not only does the C-region of IGF-1 contribute directly to the free energy of binding to the IGF-1 receptor, but also the absence of flexibility in this region eliminates binding altogether. As postulated for the binding of insulin to its own receptor, it is proposed that binding of IGF-1 to the IGF-1 receptor also involves a conformational change in which the C-terminal B-region residues detach from the body of the molecule to expose the underlying A-region residues.

Amino Acid Sequence↗
PubMed1996

The pathogenesis of cardiac allograft vasculopathy.

There has been an intensive effort in the past year to identify immunologic and nonimmunologic factors in the pathogenesis of cardiac allograft vasculopathy. Significant progress has been made regarding cell proliferation and cell death, with particular focus on cell growth factors, cell death factors, and their receptors. Endothelial cell injury and endothelin expression and production have been implicated in the development of cardiac allograft vasculopathy. A significant clinical association between dyslipidemia and cardiac allograft vasculopathy has been detected by intracoronary ultrasonography. Furthermore, proteoglycans are postulated to play an important role through lipoprotein-proteoglycan interactions. The role of cytomegalovirus infection remains controversial. Immunosuppressive agents such as rapamycin and FK506 may contribute to a reduction of vasculopathy.

Animals↗
PubMed1996

Acceptability and usefulness of vaginal washes in premenarcheal girls as a diagnostic procedure for sexually transmitted diseases. The Child Protection Centre at the Winnipeg Children's Hospital.

OBJECTIVE: To assess the suitability of vaginal washes as specimens for sexually transmitted disease diagnosis and determine the usefulness of PCR technology for Chlamydia trachomatis diagnosis in prepubertal girls. STUDY DESIGN: Paired sets of vaginal secretions were collected with swabs and by vaginal wash from 138 prepubertal girls for evaluation because of alleged sexual abuse. Detection by culture of Neisseria gonorrhoeae and C. trachomatis was compared between the two sampling techniques. PCR techniques were also used to test 29 vaginal wash specimens for C. trachomatis. RESULTS: In the prepubertal girls N. gonorrhoeae was detected in two wash specimens but in only one swab specimen; C. trachomatis was detected by culture in both paired specimens from two children and by PCR in vaginal washes from both of the two children positive by culture; PCR identified two other infected children. CONCLUSIONS: A vaginal wash technique coupled with newer molecular amplification technology may be useful in the assessment of sexually abused children.

Adolescent↗
PubMed1996

Vigabatrin as initial therapy for infantile spasms: a European retrospective survey. Sabril IS Investigator and Peer Review Groups.

PURPOSE: The efficacy and tolerability of vigabatrin (VGB) as an add-on therapy in the treatment of infantile spasm (IS) prompted physicians to explore its use as the first drug in this seizure type. METHODS: Our retrospective study included 250 infants diagnosed with IS; the data obtained were subjected to peer-group review. Of this infant population, 192 infants were considered to have classic IS and had received VGB as their first treatment for the spasms. There was a slight preponderance of boys (57%) in this population. Mean age of IS onset was 5.8 months; 60% had typical hypsarrhythmia. RESULTS: Initial suppression of spasms was obtained in 68% of infants with a median time to response of 4 days at an average VGB dose of 99 mg/kg/day. The best response was seen in those infants with tuberous sclerosis (96% response) and in those younger than 3 months at onset of spasms (90% response). Of these infants, 43 (22%) of 192 subsequently had other types of seizures, and a recurrence of infantile spasms occurred in 28 (21%) of 131 responders. At the end of this study, 96 of 192 infants who could be evaluated were seizure free with VGB monotherapy. Treatment appeared to be well tolerated, with only 33 (13%) infants with adverse events, of which the most common were somnolence (15 patients) and hyperkinesia (eight patients). In only two cases did adverse events require VGB withdrawal. CONCLUSION: This study supports the opinion that VGB may be considered an initial treatment for IS regardless of cause.

Age of Onset↗
PubMed1996

Evaluation of the Digene Hybrid Capture System for detection and quantitation of human cytomegalovirus viremia in human immunodeficiency virus-infected patients.

The Digene Hybrid Capture System (DHCS) is a solution hybridization antibody capture assay for the chemiluminescent detection and quantitation of cytomegalovirus (CMV) DNA in leukocytes. This assay was compared with the CMV antigenemia assay and shell vial and tube cultures for the detection of CMV in 234 blood specimens from 72 patients with human immunodeficiency virus. Intra- and interrun precision of the DHCS assay gave coefficients of variation of 17.8 and 16.3%, respectively. The correlation coefficient for the quantitative results obtained by the DHCS assay and the antigenemia assay was 0.911 (95% confidence interval, 0.885 to 0.930). Agreement between the DHCS assay and the other three assays ranged from 83 to 86%. The DHCS assay detected 71, 87, and 84% of specimens that were positive by antigenemia, shell vial cultures, and tube culture, respectively. A total of 92% of specimens that were positive by the DHCS assay were also positive by at least one of the other assays. Evaluation of the usefulness of quantitation of CMV DNA by using the DHCS assay and its correlation with clinical disease demonstrated that, with some exceptions, patients with clinical CMV disease tended to have high levels of DNA whereas asymptomatic patients tended to have low or undetectable levels. Overall, the DHCS assay provided a rapid, quantitative, and objective measure of CMV activity in leukocytes, but results did not always correlate with clinical disease.

AIDS-Related Opportunistic Infections↗
PubMed1996

Analysis of CA repeat polymorphisms places three human gene loci on the 8p linkage map.

The gene loci for luteinizing hormone-releasing hormone (LHRH), the beta-3 adrenergic receptor (ADRB3), and heregulin (HGL) have been assigned to the short arm of human chromosome 8, but the positions of these loci on the human genetic linkage map have not been previously reported. We have isolated simple tandem repeat polymorphisms (STRPs) for these loci. These STRPs enabled us to determine the genetic map locations for these genes.

Base Sequence↗