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Biomedical subjects

A Hawkins

Publications and source records attributed to A Hawkins.

At least 19 recordsLinked to original sources
PubMed2000

Trochanteric non-union in revision total hip arthroplasty: does it matter?

The aims of this study were to assess whether trochanteric non-union is an important factor in revision total hip arthroplasty in terms of postoperative morbidity. We studied prospectively 97 consecutive patients undergoing revision total hip arthroplasty in the years 1992-1996. All operations were performed by one surgeon through a Charnley trans-trochanteric approach. The patients were followed-up over a period of 1-4 years and at 12 months postsurgery were assessed using a modified scoring system devised by D'Aubigne. Anatomical union of the greater trochanter was assessed by an anterior-posterior pelvic radiograph at 12 months to decide if the greater trochanter was united in the correct anatomical position. The trochanteric non-union rate was 18.5% (18 out of 97 patients). There was no significant difference between the patients in terms of pain, function and satisfaction scores at one year between those with trochanteric union and those without. This study suggests that trochanteric non-union post revision total hip arthroplasty is not a cause of increased morbidity.

Adult↗
PubMed1999

An evaluation of the nurse practitioner role in a major rural emergency department.

The purpose of this pilot study was to investigate whether nurse practitioners are able to provide a level of primary health service applicable to remote/isolated settings in wound management and treatment of blunt limb trauma. It was hypothesized that there would be no significant difference in the quality of care, or the level of client satisfaction, provided by the medical officers and the nurse practitioners in the study. Two groups participated in the study, nurse practitioners and medical officers. The study used a randomized trial design. Data were collected using quantitative and qualitative methods. Two hundred and thirty-two clients participated in the study. Of this number 63 were supervised cases in the pilot trial. In the randomized trial participants were distributed between nurse practitioners and medical officers (n = 169), of which 91 were randomized to medical officers and 78 to nurse practitioners. Telephone interviews were conducted to evaluate client satisfaction. The majority of study participants were surveyed for client satisfaction (n = 132). This represents approximately 78% of the randomized sample and multivariate analysis was carried out on the data. Study results indicate that there were no significant differences between the two groups in relation to client satisfaction. Very positive outcomes of treatment were consistent across groups in the study. The study also found that there was strong support for the role of the nurse practitioner in the rural emergency setting. Recommendations include further research to measure the efficacy of nurse practitioners utilizing the selected competencies in remote/isolated settings.

Adolescent↗
PubMed1999

Genotype dependence of hepatitis C virus load measurement in commercially available quantitative assays.

Standardization and genotype independence of methods used to quantify hepatitis C virus (HCV) RNA in clinical specimens are necessary for accurate assessment of the role of HCV quantitation as a prognostic marker for HCV infection and monitoring of the response to antiviral treatment. Commercially available methods used to measure HCV loads include PCR-based (Roche Monitor) and hybridization-based (Quantiplex bDNA-2) methods. Recently, a new version of the Roche Monitor assay (version 2.0) has become available; it has been modified to achieve more equal quantitation of different HCV genotypes. Consistent with previous reports, Roche Monitor version 1.0 substantially underestimated concentrations of RNA transcripts of types 2b, 3a, 4a, 5a, and 6a and virus loads in individuals infected with genotypes 2 to 6 relative to reference tests. However, version 2.0 achieved equivalent quantitation of each genotype over a narrow quantitative range (10(3) to 5 x 10(5) copies of RNA/ml) but significantly underestimated RNA concentrations above this range. The assay showed an equivalent inability to quantify high levels of HCV RNA in plasma samples, and this was responsible for the falsely narrow range of virus loads detected in HCV-infected individuals. In contrast, the Chiron bDNA-2 assay could only measure RNA concentrations in the upper quantitative range (2 x 10(5) to 5 x 10(7) copies of RNA/ml) but showed equivalent sensitivity for genotypes 1 to 5; however, concentrations of type 6a RNA transcripts and virus loads in clinical specimens from individuals infected with type 6a were underestimated by a factor of 2 to 4. Differences were observed between PCR- and hybridization-based assays in their relative quantitation of HCV RNA transcripts and HCV genomic RNA, which may cause problems with the use of transcripts for interassay calibration.

Genotype↗
PubMed1999

Health care coverage of high school athletics in South Carolina: does school size make a difference?

Despite an apparently high injury rate, medical coverage available to these high school athletes is often not immediately present during practice and games. The purpose of the present study was to examine the current conditions of health care coverage and delivery to the football program and associated athletic departments in the public and private high schools in South Carolina. Additionally, the relationship between student enrollment and medical coverage was examined. A survey, based upon previously utilized instruments, was sent to the athletic directors at the public and private high schools with interscholastic football programs in South Carolina. The survey included questions pertaining to the medical coverage, including personnel, equipment, and record systems, for football practices and games. Based upon the results of the survey, a majority of high schools in South Carolina appear to have adequate sports medicine coverage and compare favorably with the results of similar data from other states. The medical coverage does significantly vary depending upon the enrollment size of the high school. In spite of this finding, the health care provided high school athletes is often inconsistent and training and equipment required for basic first aid is often absent.

Adolescent↗
PubMed1998

cDNA cloning, in vitro expression, and biochemical characterization of cholinesterase 1 and cholinesterase 2 from amphioxus--comparison with cholinesterase 1 and cholinesterase 2 produced in vivo.

We have isolated cDNAs coding for the complete amino acid sequences of cholinesterase 1 (ChE1) and cholinesterase 2 (ChE2) from amphioxus. Both ChE transcripts have the characteristics of H-type catalytic subunits, which are inserted in the membrane via an ethanolamine-glycan-phosphatidylinositol anchor. The members of the catalytic triad of ChEs, the three pairs of cysteine residues involved in intrachain disulfide bonding, a cysteine near the carboxy terminal of both sequences, which could mediate interchain disulfide bonding, and 11 of the 14 aromatic amino acids that line the catalytic gorge of AChE are conserved. A remarkable difference between the two enzymes is in the region of the acyl-binding pocket, which plays an important role in determining substrate specificity in cholinesterases. ChE2 contains a sequence that resembles the acyl pocket of invertebrate ChE, while the acyl-binding site of ChE1 is novel. There are also differences between the two enzymes in the peripheral anionic site, which mediates inhibition by certain ligands. In vitro expression in COS-7 cells demonstrates that ChE2 hydrolyzes acetylthiocholine almost exclusively, while ChE1 hydrolyzes both acetylthiocholine and butyrylthiocholine. Both enzymes are inhibited comparably by BW284c51, but ChE1 is considerably more resistant to inhibition by propidium, ethopropazine, and eserine than is ChE2. Velocity sedimentation indicates that ChE1 and ChE2 are present as amphiphilic and nonamphiphilic G2 forms in vivo and in vitro. Another molecular form, which sediments at 17 S, is also present in vivo. Nondenaturing gel electrophoresis in conjunction with digestion by phosphatidylinositol-specific phospholipase C demonstrates that the vast majority of ChE1 and ChE2 is present as ethanolamine-glycan-phosphatidylinositol-anchored G2 forms in vivo. ChE1 also possesses an ethanolamine-glycan-phosphatidylinositol-anchor in vitro; however, ChE2 produced in vitro could not be detected on nondenaturing gels.

Acetylthiocholine↗
PubMed1998

The effect of treatment with alpha-interferon on hepatitis G/GBV-C viraemia. The CONSTRUCT Group.

BACKGROUND: Hepatitis G virus (HGV) or GBV-C is frequently detected in patients co-infected with hepatitis C virus (HCV). This study investigated host and virologic factors influencing the response to HGV/GBV-C to alpha-interferon treatment. METHODS: HGV/GBV-C was detected and quantified by nested polymerase chain reaction. The influence of variables such as liver biopsy appearance, liver function abnormalities, and response of HCV to interferon treatment was monitored. RESULTS: Fourteen of the 25 HGV/GBV-C-infected patients treated with interferon (3-6 MIU three times a week for 6 months) became non-viraemic during treatment, although all relapsed after treatment withdrawal at 6 months, with no net change in virus load between 0 and 12 months. CONCLUSIONS: Predictive factors for clearance of HGV/GBV-C viraemia by interferon were pre-treatment severity of liver disease (median Knodell score of 4, compared with 7 for non-responders; P = 0.030) and alanine aminotransferase levels (median, 114, 182 for non-responders; P = 0.039). Clearance was associated with the treatment response of HCV. Nine of 13 who cleared HGV/GBV-C also cleared HCV, compared with 3 of 11 HGV/GBV-C non-responders; P = 0.05). The shared susceptibility of HGV/GBV-C and HCV to interferon treatment suggests a link between the mechanism of clearance of the two viruses.

Adult↗
PubMed1998

Rupture of pectoralis major during parallel bar dips: case report and review.

Rupture of the pectoralis major muscle is an uncommon athletic injury that can result in both functional and cosmetic deficiency. To date, most ruptures occurring in athletes have occurred while performing bench press or overhead lifting maneuvers. We describe a case of a pectoralis major rupture occurring while performing weighted parallel bar dips. Despite the popularity of this exercise, injuries associated with this exercise are infrequently reported. This injury can be easily detected by having the patient perform specific maneuvers on physical examination to accentuate any defect that may be present. In most cases, this injury is surgically repaired, although conservative treatment can be a successful option. Treatment options are discussed and recommendations given. A partial or complete tear of the pectoralis major muscle is a rare event and is often not easily detected on physical examination. Surgical repair is currently recommended to restore previous levels of strength and to correct the resulting cosmetic defect. Repair is rarely necessary to perform the normal activities of daily living.

Adult↗
PubMed1997

Comparison of plasma virus loads among individuals infected with hepatitis C virus (HCV) genotypes 1, 2, and 3 by quantiplex HCV RNA assay versions 1 and 2, Roche Monitor assay, and an in-house limiting dilution method.

The accuracy of different methods for the quantitation of hepatitis C virus in plasma was measured with samples from individuals infected with different genotypes and by using RNA transcripts of predetermined concentrations. Highly reproducible results were observed upon repeat testing of samples by both the original version of the Chiron branched-DNA (bDNA) assay (Quantiplex RNA assay; bDNA-1) and the currently available version (Quantiplex HCV RNA 2.0 assay; bDNA-2). A greater variability was observed in the Roche Monitor assay (correlation coefficient of 0.537, compared with 0.942 and 0.964 for the bDNA-1 and bDNA-2 assays, respectively). Significant differences in the efficiency of detection of genotypes 1, 2, and 3 were observed for the bDNA-1 and Roche Monitor assays, whereas the bDNA-2 assay and nested PCR at limiting dilution were able to quantify genotypes with equal sensitivity. By quantifying RNA transcripts of different genotypes, the sensitivities of the Roche Monitor assay for sequences of the type 2 and type 3 transcripts were estimated to be 11 and 8% of those achieved for genotype 1. When correction factors based upon these results and those from quantitation of circulating viral RNA sequences in samples from blood donors were used, the genotype-specific differences in virus load in samples from blood donors were no longer observed, consistent with previous studies with corrected values from the bDNA-1 assay. These results suggest that many of the previous studies evaluating the effect of genotype and virus load on the response to interferon using methods such as the Roche Monitor assay and other competitive PCR methods require reinterpretation. Differences in efficiency of quantitation should be taken into account in future investigations of the relationship between genotype and virus load.

Genes, Viral↗
PubMed1996

Outbreaks of influenza A among elderly hospital inpatients.

AIMS: To describe two outbreaks of influenza A that occurred in wards catering for assessment, treatment and rehabilitation of elderly patients at the Princess Margaret Hospital in Christchurch. METHODS: Infected patients and staff were identified clinically, and influenza subsequently confirmed or supported in some patients by viral antigen detection, culture of throat and nasopharyngeal swabs or serology. RESULTS: Overall, the attack rate of clinical influenza in the two wards affected was 13 of 27 patients (48%) and 15 of 26 patients (58%) respectively. Of all those with influenza, 13 patients (46%) developed lower respiratory tract infection and there were two deaths (7%) at least in part attributed to influenza. Patients in single rooms were not protected from infection. The vaccination rate among all patients was 18%. Immunised patients had a lower attack rate (21%) than those who had not received influenza vaccine that season (40%). The attack rate amongst staff in each ward was 69% and 36% respectively, and the overall staff vaccination rate was 12%. CONCLUSION: These outbreaks illustrate the severe consequences of influenza in an institutional setting.

Aged↗
PubMed1996

Heat stress lipids and schizophrenia.

The neurodevelopmental hypothesis of schizophrenia implicates abnormal or disrupted neural growth during embryogenesis. It is postulated here that stress-inducing agents acting upon a compromised cellular system resulting from abnormal plasma membrane lipids could effect the neuronal abnormalities observed in schizophrenia. The heat stress response is induced by exposure to hyperthermia as well as a variety of other agents. The response to these agents includes the cessation of most transcriptional and translational activities, accompanied by the induction of a highly specific set of proteins. A concomitant reduction in metabolic activity including cell cycle delays is also observed. Much of the enormous literature on the heat stress response concentrates on protein and DNA interactions, especially with regard to transcriptional control. However, a variety of lipids are intrinsically involved in the heat stress response. This paper will provide a brief introduction to the heat shock proteins and will explore the roles that lipids play in the heat shock response.

Heat-Shock Proteins↗
PubMed1996

High-dose chemotherapy supported by peripheral blood progenitor cells in poor prognosis metastatic breast cancer--phase I/II study. Edinburgh Breast Group.

Current treatments for metastatic breast cancer are not associated with significant survival benefits despite response rates of over 50%. High-dose therapy with autologous bone marrow transplantation (ABMT) has been investigated, particularly in North America, and prolonged survival in up to 25% of women has been reported, but with a significant treatment-related mortality. However, in patients with haematological malignancies undergoing autologous transplantation, haematopoietic reconstruction is significantly quicker and mortality lower than with ABMT, when peripheral blood progenitor cells (PBPCs) are used. In 32 women with metastatic breast cancer, we investigated the feasibility of PBPC mobilisation with high-dose cyclophosphamide and granulocyte colony-stimulating factor (G-CSF) after 12 weeks' infusional induction chemotherapy and the subsequent efficacy of the haematopoietic reconstitution after conditioning with melphalan and either etoposide or thiotepa. PBPC mobilisation was successful in 28/32 (88%) patients, and there was a rapid post-transplantation haematopoietic recovery: median time to neutrophils > 0.5 x 10(9) l-1 was 14 days and to platelets > 20 x 10(9) l-1 was 10 days. There was no procedure-related mortality, and the major morbidity was mucositis (WHO grade 3-4) in 18/32 patients (56%). In a patient group of which the majority had very poor prognostic features, the median survival from start of induction chemotherapy was 15 months. Thus, PBPC mobilisation and support of high-dose chemotherapy is feasible after infusional induction chemotherapy for patients with metastatic breast cancer, although the optimum drug combination has not yet been determined.

Adult↗
PubMed1994

Partial structure and mapping of the human myelin P2 protein gene.

The myelin P2 protein, a 14,800-Da cytosolic protein found primarily in peripheral nerves, belongs to a family of fatty acid binding proteins. Although it is similar in amino acid sequence and tertiary structure to fatty acid binding proteins found in the liver, adipocytes, and intestine, its expression is limited to the nervous system. It is detected only in myelin-producing cells of the central and peripheral nervous systems, i.e., the oligodendrocytes and Schwann cells, respectively. As part of a program to understand the regulation of expression of this gene, to determine its function in myelin-producing cells, and to study its role in peripheral nerve disease, we have isolated and characterized overlapping human genomic clones encoding the P2 protein. We report here on the partial structure of this gene, and on its localization within the genome. By using a panel of human-hamster somatic cell hybrids and by in situ hybridization, we have mapped the human P2 gene to segment q21 on the long arm of chromosome 8. This result identifies the myelin P2 gene as a candidate gene for autosomal recessive Charcot-Marie-Tooth disease type 4A.

Amino Acid Sequence↗
PubMed1994

Antagonism of cyanide intoxication with murine carrier erythrocytes containing bovine rhodanese and sodium thiosulfate.

Murine carrier erythrocytes containing bovine rhodanese and sodium thiosulfate are being explored as a new approach to antagonize the lethal effects of potassium cyanide in mice. Prior studies indicated that these carrier erythrocytes persist in the vascular system for the same length of time as normal erythrocytes and can enhance metabolism of cyanide to thiocyanate. The present studies demonstrate the ability of these carrier red blood cells containing rhodanese and thiosulfate to antagonize the lethal effects of cyanide either alone or in various combinations with sodium nitrite and/or sodium thiosulfate. Potency ratios are compared in groups of mice treated with sodium nitrite, sodium thiosulfate, and carrier erythrocytes containing rhodanese and sodium thiosulfate either alone or in various combinations prior to the administration of potassium cyanide. These results indicate that the administration of carrier erythrocytes containing rhodanese and thiosulfate alone can provide significant protection against the lethal effects of cyanide. These carrier erythrocytes potentiate the antidotal effect of sodium thiosulfate alone or the combination of sodium nitrite and sodium thiosulfate. The mechanisms of cyanide antagonism by these carrier erythrocytes and their broader conceptual significance to the antagonism of other chemical toxicants are discussed.

Animals↗
PubMed1994

The effects of changing prompted voiding schedules in the treatment of incontinence in nursing home residents.

OBJECTIVE: To determine the effects of different prompted voiding schedules on urinary incontinence on a continence unit (CU) and the maintenance of benefits on normal nursing units. DESIGN: Multiphase study with both intra- and inter-subject comparisons. PARTICIPANTS: Subjects were 41 consenting incontinent nursing home residents. Based on clinical criteria, subjects were assigned to one of four treatment groups that varied as to the schedule of prompted voiding received. MEASUREMENT: The study used chart review, Katz ADL, and MMSE. Urologic status, self-initiated toileting, urine volumes voided, and incontinence assessed by pad/pants checks were measured by research nurses. Baseline pad check data were collected on residents' normal nursing units. Residents were transferred to the CU where baseline measurement was repeated, and the effects of different prompted voiding schedules were then assessed. Indigenous staff were trained to use prompted voiding, and nurse supervisors were instructed in special procedures for enhancing maintenance of the intervention. Residents were returned to their normal units and the maintenance of improvements in continence status was assessed at 2 weeks and 3 months post-CU discharge. RESULTS: One of the four groups showed significant improvement on the CU in response to the 2-hour schedule; two groups improved on the less intensive 3-hour schedule (P < 0.05). Two groups maintained this improvement on their normal nursing units (P < 0.05); one group showed a non-significant trend toward improvement. Self-initiated toileting decreased (P < 0.05) and volume voids in an appropriate receptacle increased (P < 0.05) during training. CONCLUSIONS: Prompted voiding is an effective treatment for urinary incontinence, and a less intensive 3-hour schedule may be superior to the standard 2-hour schedule for some residents. These improvements in dryness can be maintained by normal nursing home staff if formal staff management procedures are utilized by nurse supervisors.

Aged↗
PubMed1993

Patterns of hospital care for patients with HIV infection and AIDS.

OBJECTIVE: The aims were to describe the use of inpatient resources by patients with HIV infection and patients with AIDS; to examine trends in service use over time; and to provide data for planners concerned with service provision for HIV infection. SETTING: An inner London health district reporting 9% of AIDS cases nationally. DESIGN: Data on survival times and inpatient and day care use of resources were derived from existing patient records or collected prospectively between 1983 (when the first case of AIDS was diagnosed in the district) and 31 March 1990. SUBJECTS: A total of 488 HIV positive patients of whom 396 had been diagnosed as having AIDS were studied. MEASUREMENTS AND MAIN RESULTS: Inpatient days consumed per annum; trends in the number of bed days per person year with AIDS; the lifetime inpatient use per AIDS patient; and the influence of survival on service use estimates were determined. Altogether 16.4% of a total 17,785 hospital inpatient days were attributable to HIV positive patients who did not fulfil the criteria for AIDS. For patients with AIDS, there was an initial increase in the intensity of inpatient use in 1987 when a dedicated HIV ward was opened. After 1988, however, inpatient use fell to 30.8 bed days per person year with AIDS. Patients diagnosed after April 1987 had noticeably longer survival times than those diagnosed earlier (a median of 17-18 months compared with a median of 10-11 months). From 214 lifetime service use records, it was estimated that patients with short survival (less than six months) would consume 36 days of inpatient care, while those expected to survive longer would consume approximately twice that number of days, irrespective of how much longer they survived. CONCLUSIONS: The data indicate less intensive use of inpatient care by AIDS patients over time, and hence the apparent ability to manage an increasing AIDS patient workload without a comparable increase in occupied bed days. Increases in the size of that workload and changes in the survival profile of patients, together with a relatively constant rate of service demand by longer survivors, however, will continue to place increasing strains on finite inpatient resources. Further research is needed to establish the extent to which the greater use of outpatient and community services can offset this.

Acquired Immunodeficiency Syndrome↗