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M Williams

Publications and source records attributed to M Williams.

At least 217 records · Page 12Linked to original sources
PubMed1999

Recent advances in understanding the pathogenesis of Huntington's disease.

Huntington's disease (HD) is an autosomal, dominantly inherited neurodegenerative disorder that is characterized by abnormal involuntary movements (chorea), intellectual impairment and selective neuronal loss. The expansion of a polymorphic trinucleotide repeat (the sequence CAG that codes for glutamine) to a length that exceeds 40 repeat units in exon 1 of the gene, HD, correlates with the onset and progression of the disease. The protein encoded by HD, huntingtin, is normally localized in the cytoplasm, whereas the mutant protein is also found in the nucleus, suggesting that its translocation to this site is important for the pathogenesis of HD. Although several proteins that interact with huntingtin have been identified in vitro, the significance of these interactions with the mutant protein in the pathogenesis of HD has yet to be determined. Recent progress in the development of cellular and animal models for the disease have provided invaluable insights and resources for studying the disease mechanisms underlying HD, and will be useful for screening and evaluating possible therapeutic strategies.

Animals↗
PubMed1999

Continuous intravenous midazolam infusion for Centruroides exilicauda scorpion envenomation.

STUDY OBJECTIVE: We sought to describe the effects of continuous intravenous midazolam infusion as therapy for severe bark scorpion (Centruroides exilicauda) envenomation. METHODS: A retrospective chart review from July 1, 1993, through January 1, 1998, identified all patients treated at a university hospital with International Classification of Diseases, Ninth Revision, codes 989.5 (toxic effect of venom) or E905.2 (scorpion sting causing poisoning). By using standardized collection forms, data were extracted from the medical record of every patient who had a grade III or IV envenomation and was treated with a continuous intravenous midazolam infusion. RESULTS: Our search identified 104 patients; 34 had grade III or IV envenomation. Of these, 33 were treated in the ICU with continuous intravenous midazolam infusion. Median patient age was 4 years (range, 1 to 68 years). Midazolam dosage was adjusted to induce a light sleep state to control agitation and involuntary motor activity. The median amount of midazolam resulting in the first recorded decrease in agitation and involuntary motor activity was 0.30 mg/kg (range, 0.03 to 1.76 mg/kg). This first evidence of clinical improvement was recorded as 1.00 hour (median), with a range of 0.00 to 3.75 hours. The initial midazolam infusion rate was 0.10 mg x kg(-1) x h(-1) (median), with a range of 0.01 to 0.31 mg x kg(-1) x h(-1). The maximal midazolam infusion rate was 0.30 mg x kg(-1) x h(-1) (median), with a range of 0.06 to 1.29 mg x kg(-1) x h(-1). The median time until the maximal midazolam infusion rate was 2.5 hours (range, 0.00 to 8.50 hours). The median duration of infusion was 9. 50 hours (range, 4.25 to 20.50 hours). The median length of stay in the ICU was 15.17 hours (range, 6.0 to 28.0 hours), and 85% of patients were discharged directly home. All patients had resolution of abnormal motor activity and agitation during their midazolam infusion. Transient hypoxemia without evidence of end-organ dysfunction was documented in 4 patients during midazolam therapy. CONCLUSION: A continuous intravenous midazolam infusion can be a safe, effective, and readily available treatment option for patients with grade III or IV C exilicauda envenomation.

Adolescent↗
PubMed1999

Sixty percent salvage rate for germ-cell tumours using sequential m-BOP, surgery and ifosfamide-based chemotherapy.

BACKGROUND: In germ-cell tumours (GCT), there is continuing controversy over the relative merits of dose dense therapy (increased frequency over a given time) versus vertical intensification (increased dose per fraction). The value of using a cisplatin-based dose dense approach in the salvage setting has not been documented and in addition the role of methotrexate remains uncertain. This paper reviews results from our investigations of these issues. PATIENTS AND METHODS: Between 1987 and 1996, 65 patients with relapsing or refractory germ-cell tumour received weekly m-BOP (methotrexate, bleomycin, vincristine and cisplatin) as salvage therapy. Residual masses were excised if possible and patients progressing after this received cisplatin and ifosfamide based chemotheraphy with or without high dose chemotherapy (HDCT) consolidation. RESULTS: With a median follow-up of 33 months, 34% are progression free following m-BOP, 11% who had surgery for residual masses which showed viable cancers are progression free. A further 15% who progressed following m-BOP with or without surgery were rendered progression free by third-line therapy. CONCLUSIONS: The use of m-BOP as second line therapy with deferment of cisplatin and ifosfamide based treatment to third line therapy with consolidation of third line responses with HDCT, leads to an overall progression-free survival of 60%. It does not appear that M-BOP prejudiced the response to third line therapy suggesting a lack of cross resistance. The potentially lower risk of leukaemia and infertility from m-BOP requires further evaluation.

Adolescent↗
PubMed1999

Use of idarubicin in pre-transplant conditioning in children with high-risk acute leukaemia.

The major cause of treatment failure following allogeneic bone marrow transplantation for acute leukaemia is disease relapse. In an attempt to reduce post- transplant relapse in 33 children with high-risk acute leukaemia who received a related or unrelated bone marrow transplant, the pre-transplant conditioning regimen was intensified by the addition of idarubicin. Its toxicity and effects on survival were evaluated over a 57-month period. Toxicity, largely gastrointestinal, was increased but acceptable, and there was no specific regimen-related toxicity. Relapse rates were low (24%) in this high risk group, but mortality was increased in those receiving unrelated donor grafts, largely due to sepsis. Idarubicin does appear to have a role to play in the conditioning regimen of patients with high-risk acute leukaemia undergoing BMT, and may reduce relapse rates without increasing transplant-related mortality.

Acute Disease↗
PubMed1999

Laser assisted ratio analyser 13C-urea breath testing, for the detection of H. pylori: A prospective diagnostic European multicentre study.

BACKGROUND: Novel technology based on laser optogalvanic spectroscopy called the LARA (Laser Assisted Ratio Analyser) system was developed to measure 12C/13C ratios in breath samples using stable 13C isotopes, to detect Helicobacter pylori infection. AIM: To determine the sensitivity and specificity of the 13C-LARA-urea breath test in the detection of H. pylori infection in a prospective European multicentre trial; FDA-and EMEA-approved. METHODS: Consecutive dyspeptic patients underwent diagnostic gastroscopy with biopsies for culture and histopathology, to detect H. pylori infection (gold standard). Subsequently, the LARA-urea breath test was performed using either a system without a cold trap (part I) or a system with a cold trap (part II). In both instances baseline, 30-min and 60-min breath samples were collected. The optimum cut-off level for 12C/13C ratios was determined by Receiver Operator Characteristics analysis. RESULTS: In part I, 544 out of 604 patients were evaluable (low CO2: 47; withdrawn: 13). 284 out of 544 patients (52%) were H. pylori-positive according to the gold standard. The sensitivity of the LARA-urea breath test was 95% and the specificity 94%. In part II, 257 out of 272 were evaluable (low CO2: 14; withdrawn: 1). Sensitivity and specificity were 93% and 96%, respectively. CONCLUSION: The LARA-technology represents an accurate and non-invasive testing system for the detection of H. pylori infection. Its major advantages are the use of stable 13C isotope, the high throughput of samples and the easy means of collecting, storing and transporting the samples, thus making the system convenient to both patient and clinician.

Adolescent↗
PubMed1999

Monitoring the clearance of fetal RhD-positive red cells in FMH following RhD immunoglobulin administration.

Anti-RhD immunoglobulin was administered to RhD-negative women based on estimates of fetal bleed size obtained using a direct immunofluorescence flow cytometric technique employing a FITC-conjugated monoclonal human anti-D (BRAD 3). The effectiveness of the dose administered was assessed by (i) measuring the fraction of RhD-positive fetal cells in the maternal circulation at d0, and between d2 and d10 post RhD Ig administration, (ii) quantifying the amount of anti-D detectable in maternal plasma following RhD Ig injection in the perinatal period and (iii) assessing maternal serum for the presence of immune anti-D in follow-up samples taken 3 months to 3 years after delivery. Fifty-four women were assessed, 29 having fetal bleeds in excess of 4 mL. Follow-up samples were received from 20/29 mothers after RhD Ig administration; 43-99% and 69-99% of fetal cells had been cleared by d2/3 and d5/6, respectively, in 14/20 mothers, whereas less than 50% had been cleared in the remaining mothers. Long-term follow-up samples were obtained from eight of the 29 mothers (four with bleeds >/=20 mL, two with bleeds >95 mL): none had detectable anti-D in the serum 4 months to 3 years after delivery despite the persistence of up to 36% fetal RhD-positive cells in the maternal circulation six days after delivery.

Erythrocytes↗
PubMed1999

Chinese migrants' mental health and adjustment to life in New Zealand.

OBJECTIVE: The purpose of this study was to identify and assess the relative importance of predictors of the self-rated adjustment and psychiatric morbidity of recent Chinese migrants. METHOD: Chinese migrants (n = 271) living in Auckland and aged 15 years or older completed a postal questionnaire that included the Chinese Health Questionnaire (CHQ). The majority of respondents came from Hong Kong and Taiwan. RESULTS: Most respondents did not report major adjustment problems. The psychiatric morbidity rate was 19%. Major predictors of experiencing problems included rejection by locals, being aged 26-35 years or over 45 years and low English proficiency. Major predictors of poor adjustment included unemployment, low English proficiency, lack of university education, younger age, shorter residency, expectations not met and regrets about coming to New Zealand. Predictors of minor mental disorder included regretting coming, female gender and younger age. For migrants resident 2 years or less, unemployment and underemployment were additional risk factors. Mothers with absent husbands and young people with absent parents also had elevated rates of mental disorder. CONCLUSIONS: Although the overall prevalence of mental disorder for this sample of recent migrants appears to be similar to that of the general population, significant risk factors were identified. The findings extend knowledge of the adjustment and the mental health of migrants and provide potential focal points for primary and secondary prevention interventions.

Adolescent↗
PubMed1999

Modelling the contribution of individual radionuclides to the total gamma air kerma rate for the sediments of the Ribble Estuary, NW England.

The aim of this study was to test the performance of a published dose-rate model, investigate the contribution of individual radionuclides to the total gamma air kerma rate (GAKR) and derive external doses to man in the Ribble Estuary, NW England. GAKRs were measured and sediment cores were collected in order to determine radionuclide specific activities with depth. The latter values were used as input data for the external dose-rate model. The model has a slight tendency to over-predict the GAKR, but, on average, the model predictions fall within +/-26% of the measured value. Improvements, in the present case, might be made by accounting for core shortening and variations in soil density in the input data. The model predicted that, for exposed intertidal mud sites, a range of GAKRs between 0.011 and 0.022 microGy h(-1) was attributable to Springfields discharges alone. The contribution due to 234mPa and 234Th ranged between 20 and 60%. An excess GAKR (GAKR arising from anthropogenic emissions alone) of 0.139-0.150 microGy h(-1), used in conjunction with relevant habit-survey data (for a potential critical group) and conversion factors, yielded a dose to man of 0.029-0.031 mSv year(-1).

Air Pollutants, Radioactive↗
PubMed1999

Prognostic usefulness of scoring systems in critically ill patients with severe acute pancreatitis.

OBJECTIVE: To compare prognostic scoring systems in a retrospective series of patients with severe acute pancreatitis admitted to a surgical intensive care unit (ICU). METHOD: Between January 1992 and December 1996, the charts of all patients with a discharge code of acute pancreatitis were reviewed. There were 273 charts reviewed. Of these, 12 were admitted to the surgical ICU with a diagnosis of severe acute pancreatitis. A preliminary analysis of the data considers descriptive summary statistics, such as the mean and the range. The Spearman's rank-correlation test was computed to assess concordance between the following: a) length of stay and Ranson criteria; b) length of stay and Acute Physiology and Chronic Health Evaluation (APACHE) III score; and c) length of stay and modified Glasgow Coma score. Also, an unpaired t-test was used to obtain concordance between the following: a) death and Ranson; b) death and APACHE III; and c) death and modified Glasgow Coma score. RESULTS: The prognostic score for APACHE III, Ranson criteria, and modified Glasgow Coma score were compared with the patients' length of stay. Patients who had >5 Ranson criteria, modified Glasgow Coma scores of >4, and APACHE III scores of >30 at 96 hrs (mean 71+/-16 [SD]; p < .0) subsequently died. These two patients were excluded from the Spearman's rank-correlation tests. The mean length of stay in our sample was 61.8 (range, 7-201) days. The mean Ransom criteria was 4.3 (range, 1-9). The mean 96-hr APACHE III score was 33.3 (range, 0-83). The Spearman's rank-correlation between length of stay and Ranson criteria was 0.68, with a corresponding p value of .03. Similar results were observed for the length of stay and APACHE III at 96 hrs (correlation, 0.77; p = .0098) and the length of stay and the modified (correlation, 0.78; p = .007). These data reveal that the magnitude of correlation between the length of stay and the 96-hr APACHE III and modified Imrie is larger than that between length of stay and Ranson criteria. CONCLUSIONS: Once a patient is admitted to the surgical ICU, several predictors of mortality or complications that will require long hospitalization times are evident. In this sample of patients, APACHE III scores >30 at 96 hrs, 5 or more Ranson criteria, and a modified Imrie (Glasgow) score of >3 predicted those who died or had multiple complications. Those patients with combined 48-hr and 96-hr APACHE III scores of >60 either died or had hospitalizations of >60 days. These patients had major pancreatic complications that included pancreatic necrosis, pancreatic abscess, pseudocyst, hemorrhagic pancreatitis, and pancreatic ascites.

APACHE↗
PubMed1999

Nurse, physician, and consumer role responsibility perceived by health care providers.

The article describes a study that addressed perceptions of unilateral and egalitarian role functions for nurses, physicians, and consumers in a long-term, 345-bed psychiatric facility in the western United States. Findings indicated that physicians desired to retain authority for health care decisions and that nurses, social workers, and hospital administrators preferred collaborative practice. Support for shared responsibility increased among psychiatric technicians with years of experience. Experience did not alter the attitudes of physicians, occupational therapists, and recreational therapists for physician dominance. With experience, nurses increased their belief in nurse responsibility. Despite evidence for collaborative decision making, results of this study indicate that attitudes of health care providers may prevent this tenet from being actualized.

Attitude of Health Personnel↗
PubMed1999

Implementing a caring model to improve patient satisfaction.

OBJECTIVE: To evaluate the effect of implementing a Caring Model on patient satisfaction. BACKGROUND: Patient satisfaction has become an important indicator of quality care and financial success of healthcare institutions. Acknowledging the importance of nurse caring behaviors and the impact on patient satisfaction has been relatively recent. Based on a synthesis of the literature, five caring behaviors have been formulated into a model; no single study identified the five selected behaviors included in this study. METHODS: In an acute care setting, eight patient satisfaction attributes were incorporated into a Caring Model. Implementation of the model among nursing staff members included an educational in-service, printing of the behaviors on the name badge, reminders in monthly staff meetings and nursing rounds, and inclusion of the caring behaviors in patient care documentation, job descriptions, and performance appraisals. The impact upon patient satisfaction was compared 6 months' preintervention to 6 months' postintervention. RESULTS: Postintervention, the patient satisfaction attributes of Nurses Anticipating Needs and Responds to Requests significantly increased. Attributes that began preintervention as immediate priorities for improvement became major strengths postintervention. CONCLUSIONS/IMPLICATIONS: Results of this study provide evidence that nurse caring behaviors can influence patient satisfaction. For a Caring Model to be effective, it must become an integral part of strategic planning and be implemented throughout the entire organization. To sustain the effects of the model, there must be frequent reminders among staff members. Nurse caring is an important predictor of patient satisfaction. The authors discuss the effect of implementing a caring model on patient satisfaction. In an acute care setting, eight patient satisfaction attributes incorporated into five nurse caring behaviors were evaluated pre- and postintervention. Results of the study indicated the patient satisfaction attributes of Nurses Anticipating Needs and Responds to Requests significantly increased. Attributes that began as immediate priorities for improvement before intervention became major strengths after intervention.

Attitude of Health Personnel↗
PubMed1999

Sale of sex for drugs and drugs for sex: an economic context of sexual risk behavior for STDs.

BACKGROUND AND OBJECTIVES: Persons who participate in behaviors such as drug use and buying or selling sex are at elevated risk for sexually transmitted diseases (STD)/human immunodeficiency virus (HIV) infection. GOALS: To describe the economic structure supporting drug use and the buying and selling of sex services in two urban Houston communities. STUDY DESIGN: Residents of two Houston communities participated in street-intercept interviews to obtain information on sex and drug use behaviors. RESULTS: Many members of the population reported having bought or sold sex. A history of crack use significantly predicted the trading of sex for money and drugs, and sellers of sex were more likely to have engaged in recent high-risk sexual behavior than those who had never sold sex. CONCLUSION: The data are suggestive of an underground economy for the exchange of sex for drugs or money, the existence of which facilitates the spread of STDs in high-risk communities.

Adult↗
PubMed1999

Gastrointestinal manifestations of graft-versus-host disease: diagnosis and management.

The number of bone marrow transplantations performed to treat diseases such as leukemia, lymphoma, and aplastic anemia has been increasing during the past 2 decades. Improvements in histocompatibility testing, transfusion support, conditioning regimens, and antibiotics have dramatically improved survival after transplantation. As more patients survive the acute phase of bone marrow transplantation and leave major medical centers for their homes, healthcare providers across the country are caring for these patients and their transplantation-associated complications. Graft-versus-host disease (GVHD) of the skin, liver, and gastrointestinal tract are complications that patients may experience months after transplantation. As clinicians, advanced practice nurses encounter these patients in clinics, hospitals, and intensive care units, whether it be for specific GVHD-associated problems or other health conditions. This article reviews the current standards of care for the prevention, diagnosis, and treatment of GVHD of the gastrointestinal tract.

Bone Marrow Transplantation↗