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M Harris

Publications and source records attributed to M Harris.

At least 37 records · Page 2Linked to original sources
PubMed1997

Quality assessment in contracting for tertiary care services by HMOs: a case study of three markets.

BACKGROUND: Few studies have examined the provision of tertiary care services by managed care organizations (MCOs). Moreover, little is known about the role of quality assessment and quality assurance mechanisms in the contracting process. Site visits were conducted in 1995 in three geographic areas to describe and evaluate the contracting processes for tertiary care services, especially neonatal intensive care and coronary artery bypass graft surgery, of health maintenance organizations (HMOs). METHODS: Three market areas in the United States, each with differing levels of "maturity", as primarily defined in terms of managed care penetration, were selected for study. Interviews were conducted with HMO and hospital managers about the processes for identifying potential tertiary care hospitals and mechanisms for quality assessment and quality improvement (QI) that are considered in the contracting process. FINDINGS: The most sophisticated contracting arrangements were found in the most mature market-where HMOs select hospitals for tertiary care services based on both the price and quality of services, with quality assessed through both objective and subjective data. Yet in all three markets, quality assessment was the least well-developed component of tertiary care contracting. Even in the mature market, we found inconsistent use of even validated quality or outcomes measures in hospital contracting. CONCLUSION: The potential of MCOs to increase quality depends on their ability to identify high-quality hospitals and their willingness to direct enrollees to those hospitals. Yet inconsistent evidence was found that mechanisms for evaluating and rewarding quality are being fully adopted in the three markets studied.

Catchment Area, Health↗
PubMed1997

The relationship between violence dimensions and symptom severity among homeless, mentally ill women.

Little is known about the relationship between violence and symptomatology in the lives of homeless, mentally ill women. This study investigates the possibility that specific dimensions of violence-frequency, recentness and type-may be associated with severity of psychiatric symptomatology in this population. Results indicate that each of the abuse dimensions is associated with a broad range of psychiatric symptoms and, in combination with substance abuse, account for almost one third of the variance in overall distress. These findings suggest the possibility that intensity of exposure to violence contributes to the severity of psychiatric symptoms even in women who already suffer an overwhelming number of intrapsychic and social difficulties; and that multiply traumatized women do not become desensitized to the impact of new violence. This article discusses the clinical and policy implications of these conclusions.

Adult↗
PubMed1997

Angiotropic lymphoma with endocrine involvement.

AIMS: Two cases of angiotropic high-grade B-cell lymphoma are described in which involvement of endocrine glands was a prominent feature. METHODS AND RESULTS: One patient had marked unilateral adrenomegally due to lymphoma within adrenal blood vessels. He is alive 5 years after presentation following combination chemotherapy. The diagnosis was made at autopsy in the second patient who presented with pyrexia of unknown origin and had hypothyroidism and a thyroid nodule. The thyroid gland and pituitary showed striking involvement by angiotropic lymphoma and the thyroid nodule was a cavernous haemangioma heavily colonized by lymphoma cells. CONCLUSIONS: Our cases illustrate endocrine organ manifestations of this rare disease. The condition may respond to combination chemotherapy.

Adrenal Gland Neoplasms↗
PubMed1997

Clinicopathological characteristics of peripheral primitive neuroectodermal tumour of skin and subcutaneous tissue.

AIMS: To study the clinical and pathological features of primary malignant peripheral primitive neuroectodermal tumours (PNETs) of the skin and subcutaneous tissue, to discuss the differential diagnosis, and to review the existing literature on these tumours. METHODS AND RESULTS: Eight cases of PNETs presenting in the skin and subcutaneous tissue were identified from the pathology records of the Christie Hospital, Manchester. Detailed immunohistochemical studies were performed on all cases and seven tumours were subjected to electron microscopic examination. Detailed clinical and follow-up information was obtained on seven cases. Six tumours occurred in children and adolescents and two were seen in young adults (age range, 8-36 years). No sex or site predilection was observed. Five tumours occupied the dermis and subcutis and three were entirely located in the subcutaneous tissue. Microscopically, they were composed of small round cells and seven tumours contained glycogen. Only one tumour focally exhibited Home-Wright rosettes and neuropil. Two tumours contained rhabdoid or plasmacytoid cells in places and all cases showed microcystic and pseudovascular spaces. Immunostains revealed MIC2 (8/8), NSE (7/8), PGP9.5 (7/8), beta 2 microglobulin (7/8), neurofilament protein (6/8), S100 protein (3/8), synaptophysin (2/8) and Leu-7 (1/8) positivity. Anomalous cytokeratin (4/8), desmin (2/8), myoglobin (2/8), NKIC3 (4/8) and GFAP (1/8) staining was also noted. Ultrastructurally, neuroendocrine granules were detected in five cases and one case exhibited microtubules in processes. Adequate follow-up information was available in four cases. One patient died of metastatic disease. One child developed axillary lymph node metastasis but is alive with no evidence of disease 96 months after treatment. Two other patients are alive with no residual or recurrent disease 44 and 52 months after excision and radio/chemotherapy. CONCLUSION: PNETs are rare malignant small round cell tumours of the skin and subcutaneous tissue which are probably underdiagnosed. A correct diagnosis can be made on light microscopic features, demonstration of neuroendocrine granules on electron microscopy and a combination of MIC2, beta 2 microglobulin, and more than one neural marker positivity. These neoplasms should be differentiated from other cutaneous neoplasms composed of small round cells. The number of cases of cutaneous PNETs studied so far is rather small, and no firm conclusion can be drawn about their behaviour but long-term survival is possible in some cases.

12E7 Antigen↗
PubMed1997

Correlation of virus load in plasma and lymph node tissue in human immunodeficiency virus infection. INCAS Study Group. Italy, Netherlands, Canada, Australia, and (United) States.

The impact of long-term changes in plasma viremia, produced by effective combination antiretroviral therapy, on human immunodeficiency virus (HIV) burden within tissue reservoirs is unknown. Fifteen patients who had received at least 1 year of therapy with two or three drug combinations of zidovudine, didanosine, and nevirapine had suitable samples of lymph node tissue obtained by ultrasound-guided core needle biopsy. HIV RNA was extracted from homogenized tissue samples and quantitated using a modified branched DNA assay. Results were correlated with antiretroviral treatment effect on the basis of plasma virus load measurements over the preceding 12-18 months. A statistically significant negative correlation was observed between magnitude of treatment effect on plasma viremia and lymph node virus load. These data suggest that combinations of antiretroviral drugs that produce sustained suppression of plasma HIV RNA may also be able to reduce the virus burden in lymphoid tissues.

Biopsy↗
PubMed1997

Clinical isolates of Staphylococcus aureus have osteolytic surface proteins and a proportion of the population have antibodies that block this activity: is this of prognostic significance?

Staphylococcus aureus is directly implicated in the bone destruction associated with infected orthopaedic implants and bacterial arthritis. The Oxford (laboratory) strain of this organism has surface-associated proteins (SAPs) which have potent osteolytic activity. In this study, we have examined the osteolytic activity of SAPs from clinical isolates and also investigated the role of the humoral immune response to such proteins. Nine patients with infected orthopaedic prostheses or infective arthritis, and six volunteers not suffering from overt S. aureus infection, were examined. The sera from 5/9 patients and 4/6 volunteers were able to neutralize the osteolytic activity of the SAPs. The SAPs were extracted from four clinical isolates and were found to have osteolytic activity, but with a wide range of efficacies and potencies. All four patients from whom the clinical isolates were obtained had serum IgG antibodies to the surface proteins from their autologous isolates as determined by ELISA. In conclusion, clinical isolates of S. aureus contain osteolytic SAPs which may be responsible for bone destruction. Apparently disease-free individuals and patients have antibodies able to block this activity. However, since the capacity of patients' sera to neutralize the activity of the SAPs derived from their own S. aureus isolate was not investigated, it is unclear whether these findings are of prognostic value.

Antibodies, Bacterial↗
PubMed1997

Staphylococcus epidermidis produces a cell-associated proteinaceous fraction which causes bone resorption by a prostanoid-independent mechanism: relevance to the treatment of infected orthopaedic implants.

Staphylococcus epidermidis is the most commonly isolated coagulase-negative staphylococcus from the skin, gut and upper respiratory tract. Although it is less virulent than Staphylococcus aureus, it has emerged in recent years as an important causative agent of infections associated with metal implants, prosthetic devices and i.v. lines. We have previously demonstrated that a saline wash of S. aureus contained proteins which had potent bone-resorbing activity in vitro. The purpose of this study was to determine whether gently washing S. epidermidis in saline also released osteolytically active proteins. The so-called surface-associated material (SAM) eluted from S. epidermidis in saline was able to induce osteolysis, and activity was heat and trypsin sensitive, suggesting that the active component was proteinaceous. Fractionation studies have suggested that activity is due to a small number of cationic proteins. This SAM-induced bone resorption was not inhibited by the cyclo-oxygenase inhibitor, indomethacin, or the 5-lipoxygenase inhibitors BWA70C and MK886. However, it was partially inhibited by high concentrations of interleukin-1 receptor antagonist and was completely blocked by a neutralizing antibody to tumour necrosis factor-alpha. Thus, the SAM from this organism is a potent osteolytic agent which differs from that of S. aureus SAM in not being inhibited by cyclo-oxygenase inhibitors. As adjunctive therapy is becoming necessary in infectious diseases, either as a result of the side-effects of antibiotics or their lack of efficacy, consideration should be given to the future treatment of bone infections with staphylococci in the light of the different mechanisms of action of the surface proteins produced by these bacteria.

Animals↗
PubMed1997

Integrated treatment for dually diagnosed homeless adults.

This study examined the effects of integrating mental health, substance abuse, and housing interventions for homeless persons with co-occurring severe mental illness and substance use disorder. With the use of a quasi-experimental design, integrated treatment was compared with standard treatment for 217 homeless, dually diagnosed adults over an 18-month period. The integrated treatment group had fewer institutional days and more days in stable housing, made more progress toward recovery from substance abuse, and showed greater improvement of alcohol use disorders than the standard treatment group. Abuse of drugs other than alcohol (primarily cocaine) improved similarly for both groups. Secondary outcomes, such as psychiatric symptoms, functional status, and quality of life, also improved for both groups, with minimal group differences favoring integrated treatment.

Adolescent↗
PubMed1997

An STS-based radiation hybrid map of the human genome.

We have constructed a physical map of the human genome by using a panel of 83 whole genome radiation hybrids (the Stanford G3 panel) in conjunction with 10,478 sequence-tagged sites (STSs) derived from random genomic DNA sequences, previously mapped genetic markers, and expressed sequences. Of these STSs, 5049 are framework markers that fall into 1766 high-confidence bins. An additional 945 STSs are indistinguishable in their map location from one or more of the framework markers. These 5994 mapped STSs have an average spacing of 500 kb. An additional 4484 STSs are positioned with respect to the framework markers. Comparison of the orders of markers on this map with orders derived from independent meiotic and YAC STS-content maps indicates that the error rate in defining high-confidence bins is < 5%. Analysis of 322 random cDNAs indicates that the map covers the vast majority of the human genome. This STS-based radiation hybrid map of the human genome brings us one step closer to the goal of a physical map containing 30,000 unique ordered landmarks with an average marker spacing of 100 kb.

Animals↗
PubMed1997

Violence against women: an education program for rural community health workers.

This study aimed to identify the educational needs of community-based rural health professionals regarding violence against women, and was funded under the Rural Health Support, Education and Training (RHSET) program. Focus groups and teleconferences were conducted with health workers, organisations and key individuals in the Wide Bay Region, Queensland, Australia. As a result, an education package has been designed that will provide specific training in violence against women for rural and remote health professionals working in the field. Rural health community workers identified the need to enhance their intervention skills and understanding on the issue of violence against women. A distance education framework based on adult and guided learning principles has been developed to meet this need. Six areas were identified as important learning needs and included: (i) violence against women as a public health concern; (ii) The role of the community health worker; (iii) How the community health worker can empower women experiencing violence in their lives; (iv) Enhancing and developing supportive networks; (v) Building on community development action; and (vi) 'Where to next' for community health workers.

Adult↗
PubMed1997

An immunohistochemical study of oral submucous fibrosis.

Oral submucous fibrosis (OSF) is a chronic disease of the oral cavity characterized by inflammation and progressive mucosal fibrosis. These reactions may be the result of either direct stimulation from exogenous antigens like areca alkaloids or by changes in tissue antigenicity that may lead to an autoimmune response. This study investigated the presence and distribution of inflammatory cells and MHC class II antigen expression by epithelial and immunocompetent cells using a three-stage immunoperoxidase method on frozen sections. Thirty OSF tissue specimens and ten normal buccal mucosae were studied and compared. All tissues were investigated using antibodies to T cells (CD3), T helper/inducer cells (CD4), T suppressor/ cytotoxic cells (CD8), B cells (CD20), naive T cells and monocytes (CD45RA), macrophages, Langerhans' cells (CD68) and HLA-DR-positive cells (HLA-DR alpha). The predominant cell populations detected in normal tissues were CD3, CD4 and HLA-DR-positive cells. The distribution of CD4-positive cells was similar to that of CD3-positive cells, which were scattered, often uniformly distributed, both in the epithelium and connective tissue. CD8-positive cells were occasionally seen in the normal epithelium and lamina propria. Few scattered B cells (CD20) and macrophages (CD68) were observed in normal mucosa. Naive T cells (CD45RA) were seen in all normal tissues focally concentrated around the connective tissue papillae, with a similar distribution to that of CD3-positive cells. All normal sections showed HLA-DR-positive cells scattered both in the epithelium and in the lamina propria. Epithelial cells did not show any positive reaction to this antibody and many intraepithelial positive cells showed a dendritic morphology. The cell population detected in OSF showed higher numbers of CD3 and HLA-DR-positive cells compared with those of the normal tissues. The pattern of staining for CD4-positive cells in OSF tissues was similar to that of CD3-positive cells both in the epithelium and connective tissue and was higher than that in normal tissues. A few scattered CD8-positive cells and only occasional CD20- and CD68-positive cells were seen in OSF sections. Few CD45RA-positive cells were found in the epithelium and lamina propria of OSF sections. However, OSF specimens showed high numbers of HLA-DR-positive cells in the basal layer of the epithelium, juxtaepithelium and in the lamina propria in a similar distribution to that of CD3 cells compared with the normal tissues. Most HLA-DR-positive cells in the epithelium showed dendrites directed vertically towards the surface. The increased evidence of CD4 and HLA-DR-positive cells in OSF tissues suggests that most lymphocytes were activated and shows an increased presence of Langerhans' cells. The presence of these immunocompetent cells and high ratio of CD4 to CD8 in OSF tissues suggest an ongoing cellular immune response leading to a possible imbalance of immunoregulation and alteration in local tissue architecture.

Adolescent↗
PubMed1997

Housing status among formerly homeless dually diagnosed adults.

OBJECTIVE: Residential outcomes of homeless adults with severe mental illness and a substance use disorder were studied over 18 months during which participants received integrated dual diagnosis services and housing supports based on a continuum model. METHODS: Interviews with 158 participants at baseline and at six-, 12-, and 18-month follow-ups assessed housing status, residential history, substance abuse and progress toward recovery, psychiatric symptoms, and quality of life. Complete data were available for 122 participants. If participants lived continuously in high-quality housing with no housing loss or nights of homelessness during the final six months of the study, they were classified as having stable housing. RESULTS: Of the 122 participants for whom complete data were available, 64 (52 percent) achieved stable housing. Most participants who achieved stable housing first entered staffed and supervised housing and then moved to independent arrangements by the end of the study. Stable housing during the final evaluation period was associated with lower substance use, greater progress toward substance abuse recovery, and higher quality of life. Final housing status was not predicted by baseline variables but was predicted by progress toward recovery during months 0 to 6 and 6 to 12 and by less severe drug use during months 6 to 12. Participants who abused no illicit drugs during months 6 to 12 were almost three times as likely to achieve stable housing as those who abused illicit drugs. CONCLUSIONS: Housing stability is strongly mediated by substance abuse and progress toward recovery. Nevertheless, when formerly homeless persons with dual diagnoses are provided integrated dual diagnosis treatment, they can gradually achieve stable housing.

Adult↗
PubMed1997

Model of complications of NIDDM. I. Model construction and assumptions.

OBJECTIVE: To develop a model of NIDDM for analyzing prevention strategies for NIDDM. RESEARCH DESIGN AND METHODS: A Markov type model with Monte Carlo techniques was used. Age, sex, and ethnicity of cohort was based on U.S. data. Incidence rates of complications were also based on community and population studies. RESULTS: Nonproliferative retinopathy, proliferative retinopathy, and macular edema are predicted in 79, 19, and 52%, respectively, of people with NIDDM; 19% are predicted to develop legal blindness. Microalbuminuria, gross proteinuria, and end-stage renal disease related to diabetes are predicted in 53, 40, and 17%, respectively. Symptomatic sensorimotor neuropathy and lower-extremity amputation are predicted in 31 and 17%, respectively. Cardiovascular disease is predicted in 39%. Higher rates of complications (1.1-3.0x) are predicted in minority populations. Predicted average life expectancy is 17 years after diagnosis. CONCLUSIONS: A probabilistic model of NIDDM predicts the vascular complications of NIDDM in a cohort representative of the incident cases of diabetes in the U.S. before age 75 years. Predictions of complications and mortality are consistent with the known epidemiology of NIDDM. The model is suitable for evaluating the effect of preventive interventions on the natural history of NIDDM.

Adult↗
PubMed1997

Model of complications of NIDDM. II. Analysis of the health benefits and cost-effectiveness of treating NIDDM with the goal of normoglycemia.

OBJECTIVE: To analyze the health benefits and economics of treating NIDDM with the goal of normoglycemia. RESEARCH DESIGN AND METHODS: Incidence-based simulation model of NIDDM was used. Hazard rates for complications were adjusted for glycemia using risk gradients from the Diabetes Control and Complications Trial. Treatment costs were estimated from national survey data and clinical trials. Incremental costs and benefits were expressed in present value dollars (3% discount rate). Life-years were adjusted for quality of life, yielding quality-adjusted life-years (QALYs). RESULTS: Comprehensive treatment of NIDDM that maintains an HbA1c value of 7.2% is predicted to reduce the cumulative incidence of blindness, end-stage renal disease, and lower-extremity amputation by 72, 87, and 67%, respectively. Cardiovascular disease risk increased by 3% (no effect of treating glycemia is assumed). Life expectancy increased 1.39 years. The cost of treating hyperglycemia increased by almost twofold, which is partially offset by reductions in the cost of complications. The estimated incremental cost/QALY gained is $16,002. Treatment is more cost-effective for those with longer glycemic exposure (earlier onset of diabetes), minorities, and those with higher HbA1c under standard care. CONCLUSIONS: The incremental effectiveness of treating NIDDM with the goal of normoglycemia is estimated to be approximately $16,000/QALY gained, which is in the range of interventions that are generally considered cost-effective.

Adult↗
PubMed1997

Failure mechanisms of anatomic porous replacement I cementless total hip replacement.

The APR-I Hip System was designed for metaphyseal bone attachment by proximal patch porous coating and the acetabular component was a hemisphere fixed with screws. The results of 100 consecutive primary total hip arthroplasties performed with the APR-I were studied in patients still alive after an average of 6.7 years. The selection of hips for implantation of this hip system was limited to those patients in whom a satisfactory intraoperative fit could be obtained. This resulted in a distribution of patients such that 75% were younger than age 65 years and only 15% had osteoporotic bone. The revision rate was 16% with a mechanical failure rate of 11%. Seventy percent of hips had progressive loss of fixation. loss of femoral component fixation was correlated with younger patient age, higher patient activity level, metaphyseal fill of less than 90%, and increased polyethylene wear and osteolysis. Eighty-nine percent of hips maintained femoral neck contact with the porous coated collar. The acetabular component was well fixed in 97% of hips. The failure rate of the APR-I stem is unacceptably high and this stem is no longer used by the authors.

Adult↗
PubMed1997

A survey of general practitioner's confidence in their management of elderly patients.

OBJECTIVE: To assess the confidence of GPs in assessing physical, psychological and social functioning in the elderly and managing complex multi-systems in cooperation with other services and resources in the community. METHOD: One hundred and ninety general practitioners in the Fairfield and Liverpool municipalities were mailed a self-administered anonymous questionnaire which assessed their confidence and barriers to caring for the elderly. RESULTS: One hundred and six general practitioners responded (response rate 55%) with complete questionnaires. Most felt confident in identifying the physical and psychological problems but few felt confident in identifying social problems. Common barriers were patient factors such as reluctance to acknowledge problems, and lack of time. They were equally confident in diagnosing and managing most specific conditions but less so for dementia, depression and functional limitation. While general practitioners rated liaison with geriatricians and primary care services highly, aged care assessment teams were perceived to be poor communicators. CONCLUSIONS: Although most general practitioners felt confident about their general management of their elderly patients, many felt less confident in identifying social problems. More education needs to be provided in 'shared care' of dementia, functional limitations, depression and incontinence.

Aged↗