Biomedical subjects

M Burke

Publications and source records attributed to M Burke.

At least 55 records · Page 3Linked to original sources

PubMed2000

A prospective study of plasma nitrates following human heart transplantation-relevance to myocardial function.

BACKGROUND: Nitric oxide (NO) has been shown to affect myocardial function in positive and negative inotropic ways. Expression of inducible nitric oxide synthase and release of nitric oxide into the circulation has been associated with acute rejection in animal studies. The role of NO and the associated myocardial dysfunction seen during acute rejection in humans has not been adequately defined. In a prospective sequential study, we have studied the relationship between plasma nitrate and biopsy-proven acute rejection, and systolic and diastolic function after heart transplantation. METHODS: Biopsies were performed weekly and then fortnightly up to 12 weeks after transplantation and on clinical indication of rejection in 37 patients. Plasma nitrates were obtained on the morning of each biopsy (total 341). An echocardiogram was performed immediately prior to each biopsy in which the systolic parameters, ejection fraction (EF) and fractional shortening (fs), and the diastolic parameters, isovolumetric relaxation time (IVRT), mitral valve pressure half-time (MVPHT), mitral valve deceleration time (MVDT), e:a ratio, and a wave duration, were measured. RESULTS: Plasma-nitrate level showed no significant correlation with the systolic parameters, EF or fs, or with changes in EF or fs. No significant correlation was found between plasma-nitrate level and the diastolic parameters IVRT, MVPHT, MVDT, mitral valve a wave duration, or e:a ratio. CONCLUSIONS: This study has shown no correlation between plasma nitrate and impaired systolic or diastolic function after heart transplantation. Instead there was a weak trend for elevated nitrate to be associated with better systolic function.

Adult↗

PubMed2000

Overexpression of p21WAF1/CIP1 and MDM2 characterizes serous borderline ovarian tumors.

Ovarian epithelial tumors are classically divided into benign, malignant, and borderline or of low malignant potential. It is controversial whether this last group of tumors should be considered benign or malignant. Expression of cell cycle markers has recently been linked to tumor behavior and response to treatment. It has been shown that one of the pathways through which the p53 gene controls the cell cycle is by transactivating p21WAF1/CIP1, a cyclin-dependent kinase (cdk) inhibitor. By inhibiting cdks, p21WAF1/CIP1 blocks the G-1 to S-phase transition in the cell cycle. p53 can be regulated by MDM2 (murine double minute-2) through direct inactivation or promotion of its cytoplasmic degradation. In an attempt to investigate the cell cycle checkpoint mechanisms of these tumors, we studied the expression of p53, Ki-67, MDM2, and p21WAF1/CIP1 by immunohistochemistry. We analyzed the expression of these proteins in 19 cystadenomas (8 serous and 11 mucinous), 40 borderline tumors (31 serous and 9 mucinous), and 18 serous carcinomas of the ovary. p21WAF1/CIP1 was expressed in 7 of 19 (37%) benign cystadenomas, 32 of 40 (80%) borderline tumors (93.5% of serous and 33% of mucinous), and in 9 of 18 (50%) serous carcinomas. Ki-67 was only weakly expressed in 8 of 19 (42%) benign cystadenomas, all borderline tumors showed Ki-67 staining in less than 50% of the cells, and 55% of serous carcinomas stained in more than 50% of tumor cells. p53 was absent in all but 1 of the cystadenomas, was expressed in 9 of 40 (22.5%) borderline tumors (25.8% of serous and 11% of mucinous), and in 10 of 18 (55%) carcinomas. All 11 implants of serous borderline tumors expressed p21WAF1/CIP1. Most serous borderline tumors expressed higher levels of MDM2 compared with the benign cystadenomas and carcinomas. Four of the serous borderline implants (40%) expressed MDM2. Coexpression of p21WAF1/CIP1 and MDM2 characterizes serous borderline tumors of the ovary and their implants, which suggests that these cell cycle control proteins are important in these tumors and may be related to tumor progression. Low expression of p53 protein in serous borderline tumors might be in part mediated by MDM2. This suggests that the p53 pathway is intact in most of these tumors, in contrast with carcinomas, in which high expression of p53 has been related to mutations of this gene.

Biomarkers, Tumor↗

PubMed2000

Spontaneous rupture of the liver associated with a primary angiosarcoma: case report.

A case of fatal spontaneous rupture of the liver caused by primary angiosarcoma is described. Spontaneous rupture of the liver is a rare clinical and pathological entity associated with high morbidity and mortality rates. Possible causes include infections such as hydatid disease, infiltrating conditions such as amyloidosis, inflammatory disorders such as the vasculitides, malignant and benign tumors, and tumorlike conditions. As in the case presented, the finding of a ruptured liver raises the possibility of blunt abdominal trauma, and the circumstances and scene should be assessed. The possibility of terminal resuscitation attempts should also be considered as a possible cause.

Autopsy↗

PubMed2000

Primary peritonitis due to group A streptococcus.

Primary peritonitis is a rare condition occurring, by definition, in patients without underlying causes, such as perforated viscus, pre-existing ascites, or nephrosis. We report a case of primary peritonitis and shock due to group A beta-hemolytic streptococcus, a rare etiology. A review of the world's literature shows a predilection for women to have this condition. The entry site is obscure in most cases. Asymptomatic genital tract colonization may be a portal of entry in some women. Shock or toxic shock syndrome often accompany the abdominal findings. Laparotomy to exclude a perforated viscus may be unavoidable. Despite the significant morbidity, expeditious and appropriate antibiotic therapy is curative.

Adult↗

PubMed2000

Duplication of the hypophysis.

The authors describe an 11-year-old girl with duplication of a pituitary gland and hypertelorism. Of the 14 cases described to date, only 2 others have lacked associated major facial or oral anomalies. Two separate glands, respective stalks and hypothalamic enlargement were incidentally found on MR imaging performed to evaluate the patient's complaint of anosmia. A tortuous fusiform dilatation of one pericallosal artery was also discovered. A review of hypophyseal embryogenesis is presented. It is now evident that duplication of the pituitary can occur without other major dysmorphias. This may infer that notochord/prochordal plate deficits are not a prerequisite for hypophyseal duplication.

Cerebral Angiography↗

PubMed2000

Antibiotics for sore throat: impact of feedback to patients on the probability of bacterial infection.

Antibiotics are overused in the management of sore throat. Using a scoring system with 108 attenders, we provided feedback on the likelihood of bacterial infection and measured the impact on initial patient expectation for antibiotic therapy. Patient attitudes and beliefs regarding antibiotics were also examined. Of sixty two patients whose score suggested viral infection, 18(29%) opted not to take an antibiotic prescription. The 42(67%) who still wanted an antibiotic, despite being told it was "unlikely or highly unlikely" to help, had a higher mean attendance rate for sore throat (1.63 v 0.83 (p = 0.14)) and other illness (6.53 v 4.22 (p = 0.22)), and a higher mean re-attendance rate following the study (1.68 v 0.50 (p = 0.025)). Qualitative analysis suggests that this subgroup may believe in the analgesic properties of antibiotics.

Adolescent↗

PubMed2000

MR imaging of female pelvic malignancies.

This article reviews the most common gynecologic malignancies and their MR imaging features. The overall goal remains early disease detection and accurate staging to optimize treatment and thereby to reduce morbidity and mortality. MR imaging, when available, may play an important role in the accurate staging and evaluation of female pelvic malignancies and, thus, may become part of their routine investigation. In the authors' experience, MR imaging has proven useful in the preoperative evaluation of these malignancies. With ongoing research into imaging protocols designed to improve image quality and reduce examination time, the importance of MR imaging will continue to grow.

Female↗

PubMed1999

Immunologic responses of HIV-1-infected study subjects to immunization with a mixture of peptide protein derivative-V3 loop peptide conjugates.

V3 loop peptide sequences from several HIV-1 strains were covalently linked to purified protein derivative (PPD) of Mycobacterium tuberculosis. A mixture of PPD conjugates of V3 loop peptides from six different strains of HIV-1 induced a stronger antibody response than a single V3 peptide-conjugate administered to guinea pigs and humans. Sera from animals immunized with a PPD-six peptide-PPD conjugate neutralized multiple primary-isolate strains of HIV-1. Potent immune responses were noted only when animals were primed with bacillus Calmette-Guerin (BCG), PPD was covalently bound to the peptides, and PPD was used as the carrier protein. Based on these animal studies, an immunogen consisting of PPD-conjugated V3 loop peptides from five HIV-1 strains was tested in 7 HIV-1 seropositive PPD skin test positive study subjects. Vaccinees exhibited over time a uniform increase in neutralizing antibodies for both laboratory adapted and primary isolates of HIV-1, including strains from multiple clades. In 3 patients with baseline viral loads between 8000 and 12,000 RNA copies/ml, the viral load declined in 2 patients to <400 copies/ml and in 1 patient to 1200 copies/ml without concurrent administration of highly active antiretroviral therapy (HAART).

AIDS Vaccines↗

PubMed1999

Posttransplantation B lymphoblastic leukemia with Burkitt-like features.

BACKGROUND: Posttransplantation Epstein-Barr virus-associated lymphoproliferative disease (PTLPD) occurs as a spectrum of disease ranging from benign, polyclonal, localized lymphoid hyperplasia to malignant, monoclonal, disseminated lymphoma, sometimes involving the bone marrow. To our knowledge, PTLPD has not been previously reported to present as acute lymphoblastic leukemia. METHODS: We report the case of a boy who developed PTLPD in the form of acute lymphoblastic leukemia 6 years after cardiac transplantation. He had greater than 90% bone marrow invasion by Epstein-Barr virus-positive B lymphoblasts with Burkitt-like features and a t(8;14) translocation. RESULTS: He was successfully treated with combination chemotherapy but unfortunately died, 6 months after completing treatment, from ischemic heart disease. CONCLUSIONS: B lymphoblastic leukemia may occur as a manifestation of PTLPD and should be included in the classification of these diseases. Bone marrow examination should be an essential part of the investigation of patients suspected of having PTLPD.

Administration, Oral↗

PubMed1999

Increased intracellular accumulation of macrophage inflammatory protein 1beta and its decreased secretion correlate with advanced HIV disease.

Considering that the chemokine macrophage inflammatory protein 1beta (MIP1beta) may serve as a competitive inhibitor for HIV entry, the objective of this study was to compare intracellular and extracellular levels of MIP1beta, in untreated HIV-infected individuals. HIV patients and healthy controls were tested by two-color flow cytometry for intracellular MIP1beta, in freshly explanted CD4 and CD8 lymphocytes, and in monocytes. Sera and plasma collected on the same day were tested, respectively, by enzyme-linked immunosorbent assay (ELISA) for MIP1beta concentration and for number of HIV-RNA copies, using nucleic acid sequence-based amplification procedure (NASBA) methodology. Results demonstrate that a high intracellular level of MIP1beta appears to be linked to a deterioration in the immune status of HIV patients (i.e., low CD4 counts) and to a high viral load. Moreover, an inverse relationship exists between the intracellular and the "secreted" form of MIP1beta, thus leading to the hypothesis that the regulation of cellular accumulation and secretion of MIP1beta and of other chemokines may be disrupted during AIDS development.

Case-Control Studies↗

PubMed1999

Sample size determination for proving equivalence based on the ratio of two means for normally distributed data.

Equivalence trials aim to demonstrate that two treatments do not differ by more than a prespecified clinically irrelevant amount. We consider the problem when equivalence is defined in terms of the ratio of population means and the original (untransformed) data are normally distributed. Application of the intersection-union principle to the test proposed by Sasabuchi results in a two one-sided tests procedure of size alpha. We give the associated 100 (1-2 alpha) per cent confidence interval and derive the exact methods for calculation of power and sample sizes for the parallel group design and the two-period cross-over. We present tables and figures of required sample sizes and achieved power.

Administration, Inhalation↗

PubMed1999

Pulmonary adiaspiromycosis in a patient with acquired immunodeficiency syndrome.

Adiaspiromycosis is a noninfectious, nonarthropod-transmitted fungal infection that occurs worldwide in lower vertebrates, especially rodents. However, humans may become accidental hosts. Reported here is a case of adiaspiromycosis of the lung in an HIV-positive, 40-year-old, bisexual man who first presented with cough and dyspnea. Cultures of a bronchoalveolar lavage and protected brush specimen revealed the presence of fungal elements that were identified as Emmonsia parva var. parva. The patient was successfully treated with amphotericin B and thereafter with fluconazole. This organism should be added to the list of pathogens that cause pulmonary infection in AIDS patients.

AIDS-Related Opportunistic Infections↗

PubMed1999

Anti-HIV indeterminate western blot in dialysis patients: a long-term follow-up.

In a group of 520 patients undergoing chronic hemodialysis, 23 (4. 4%) were enzyme immunoassay (EIA) positive for human immunodeficiency virus (HIV) and indeterminate by Western blot (IWB) analysis. The antibodies were mostly directed against p24 and p55 antigens. A comparison between hemodialysis patients with and without IWB showed significant differences between the two groups with respect to number of units of blood transfused, history of renal transplant rejection, and Rh status. No significant differences were observed with respect to ethnic group, nature of renal disease, duration of hemodialysis, associated diseases, and ABO blood group. The HIV IWB phenomenon may represent abnormal immune reactivity as a result of transplantation antigens and/or autoantibody formation. Five-year follow-up of the HIV EIA-positive IWB patients showed that none had seroconverted to HIV-positive status.

Blood Donors↗

PubMed1999

Characterisation of the rat lung lavage model as biological assay for testing the activity of surfactant preparations.

The present report describes how pharmacological assays may be validated and sets a basis for a discussion on the validation of biological test systems. The note for guidance on the validation of analytical procedures published by the European agency for the evaluation of medicinal products was adapted to the validation of a pharmacological test system. The presently described rat lung lavage test (RLL-test) is an animal model that has great similarities to the pathophysiology of the acute respiratory distress syndrome of humans. In this RLL-test, the activity of surfactants can be tested in a standardised fashion. The usefulness of the point estimator and the corresponding confidence intervals (CI) as a statistical test procedure for equivalence was demonstrated. A validation can be based on the above mentioned guidance but should be adjusted to pharmacological needs. Based on the presented experiences, it can be concluded that a specific guideline for validation of pharmacological or biological tests is desirable.

Anesthesia↗

PubMed1999

Supportive telephone outreach as an interventional strategy for elderly patients in a period of crisis.

During the Gulf War in 1991 a telephone-based support system was established for elderly patients living at home in Israel. The study population involved 93 elderly patients (mean age 74), who had recently been discharged from hospital and were chosen for supervision by the Home-Care Unit of the Tel Aviv Sourasky Medical Center, Israel. Two different teams were involved with the telephone support calls: secretarial staff (nonprofessional team) and social workers (professional team). The research examined the characteristics of the study population and also included a comparison between the two groups of patients receiving the psycho-social support. The latter indicated that better results of outcome indices were achieved by the professional team. Further, this study demonstrated the feasibility of telephone-support outreach as an interventional strategy for psycho-social support for elderly patients at a time of crisis.

Aged↗

PubMed1999

Small things from small places.

BACKGROUND: The federal government has recently acknowledged that more highly skilled GPs would reduce the health bill by decreasing the level of specialist referral. OBJECTIVE: Practical procedures should form part of every day practice, however, gaining skills and the practical tips that make procedures easier can be difficult. This article describes the skills required for the removal of foreign bodies from children. DISCUSSION: The retrieval of foreign bodies from children requires patience, preparation and confidence. Plan your approach carefully and take your time as you may only have one chance at grasping the object before the child becomes uncooperative.

Child↗

PubMed1999

Carcinoma of the male breast--a review of 91 patients from the Johannesburg Hospital breast clinics.

OBJECTIVES: To characterise male breast carcinoma among black South Africans and to compare the findings with those for white males in the same area. METHODOLOGY: Data were prospectively collected for all patients presenting to the Johannesburg Hospital breast clinics over a 14-year period. The breast clinics see all patients from Johannesburg and the surrounding area, both from government hospitals and private clinics. Sixty-nine black, 20 white and 2 Asian males were found to have breast carcinoma during this period. RESULTS: Although black males presented with a longer history of symptoms than white males (median 12 v. 2 months), and at a later stage of their disease (> 80% v. 40% stage III or IV), there did not appear to be any fundamental differences in the disease between the two groups. Median age at presentation (59 v. 62 years) was not significantly different, the spectrum of histopathological types was similar, and 5-year survival stage for stage was the same: 88% for stage I, 50% for stage II, 27% for stage III, and 5% for stage IV. The incidence of carcinoma among black males appeared to be the same as for white males, but there did seem to be a decreased incidence of breast carcinoma in the black female population. CONCLUSIONS: There are no true differences between breast carcinoma occurring in black and white South African males. Previous African reports have suggested an increased incidence of breast carcinoma in black males because the figures have only been compared with those for black females.

Adult↗

PubMed1999

Nursing in genitourinary medicine: 10 years on from the Monks Report. The membership of GUNA. Genito-Urinary Nurses Association.

Various reports and surveys since 1988 have highlighted differences in gradings and diversity of roles and responsibilities of nurses in genitourinary medicine (GUM). In addition there was no method of defining how many nurses work in the speciality. Therefore the Genito-Urinary Nurses Association (GUNA) undertook a survey last year to establish how many nurses, of what grade, undertaking what roles are working in GUM clinics. Over half the clinics in the UK responded, from full-time busy London clinics to small part-time rural clinics. The results suggest approximately 2000 nurses working in GUM nationally, with a wide diversity of grades, roles and responsibilities still apparent 10 years after the Monks Report. Further analysis of the data obtained by the survey is given in the report.

Female Urogenital Diseases↗