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Biomedical subjects

J Parker

Publications and source records attributed to J Parker.

At least 109 records · Page 6Linked to original sources
PubMed1996

Operative laparoscopic management of adnexal cysts: initial experience at the Royal Women's Hospital 1991-1994.

The introduction of operative laparoscopic surgery for benign adnexal cysts had led to shorter postoperative hospitalization (mean stay of 2.0 days) in association with a low rate of major complications (1.6%). A planned laparoscopic approach was successful in 95.2% (179/188) of patients. The majority of women were premenopausal (93.6%) and the most common procedure performed was an ovarian cystectomy (73.5% of cysts). Three ovarian cysts that were thought to be benign by preoperative and intraoperative assessment were subsequently found to be ovarian tumours of low malignant potential after histological examination. Operative laparoscopy has become the preferred mode of treatment for benign adnexal cysts at the Royal Women's Hospital. It confers a wide range of benefits to patients, reduces health-care costs and appears to be a safe and effective treatment modality.

Adolescent↗
PubMed1996

Cardiopulmonary arrest in pregnancy: successful resuscitation of mother and infant following immediate caesarean section in labour ward.

Our patient experienced cardiopulmonary arrest secondary to profound hypotension and was unable to be resuscitated with external cardiac massage and assisted ventilation. This case demonstrates the need for continued vigilance by medical and nursing staff when epidural anaesthesia is being established. Resuscitation equipment should be available in the labour ward as cardiopulmonary resuscitation and immediate Caesarean section can be lifesaving in the event of a cardiopulmonary arrest.

Adult↗
PubMed1996

Impact of the 1991 NHS reforms on the availability and use of coronary revascularisation in the UK (1987-1995)

OBJECTIVE: To describe changes in the availability, utilisation, and waiting times for coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA) between 1987/88 and 1994/95 and to review commissioning of these services. DESIGN: A series of cross sectional surveys and interviews with purchasers and providers. SETTING: Four health regions in the United Kingdom. PATIENTS: All residents aged 25 years or more who underwent coronary revascularisation. RESULTS: There has been little change in the availability of consultants in cardiology in specialist centres, while the number of non-consultant cardiologists has risen significantly. The availability of consultant surgeons more than doubled in some regions, while non-consultant surgical staff increased by 40-90%. The NHS rate of use of both CABG and PTCA has increased steadily since 1987/88. In 1994/95, only two districts had CABG rates of less than 300 per million population. The additional contribution of privately funded cases varied between 14-23% for CABG and 7-30% for PTCA. Regional rates varied 1.3-fold for CABG and threefold for PTCA in 1994/95, while district rates of CABG varied 3.6-fold and PTCA 18-fold. Revascularisation rates were higher in districts with least need in 1991/92 and this persisted over the following three years. The overall waiting time for CABG (214 days) was largely unchanged from 1992/93 (234 days). The overall waiting time for PTCA (138 days) was 25% shorter than in 1992/93 (185 days). Prioritisation of patients waiting over a year had not yet adversely affected the waiting time of more urgent patients. Commissioning has faced a complex web of interconnected problems which, in general, caused more problems for purchasers than providers initially but which appear to be of increasing concern to providers. CONCLUSIONS: The 1991 NHS reforms had had no observable impact on the availability and use of coronary revascularisation by 1995. Continued monitoring is necessary to detect any delayed effect.

Adult↗
PubMed1996

Clinical significance of bcl2 and p53 protein expression in diffuse large B-cell lymphoma: a population-based study.

PURPOSE: We studied the prognostic significance of bcl2 and p53 protein expression in relation to clinical and pathologic characteristics in patients with diffuse large B-cell lymphoma (LCL). PATIENTS AND METHODS: Three hundred seventy-two patients with LCL were retrieved from a population-based registry for non-Hodgkin's lymphoma (NHL). bcl2 and p53 protein expression was studied on paraffin-embedded tumor tissue by immunohistochemistry in relation to clinical factors. Response to therapy and survival were analyzed in 165 patients who were uniformly staged and treated and for whom all prognostic data were available according to the International Prognostic Index (IPI). RESULTS: Forty-five percent of tumors showed strong expression of the bcl2 protein (bcl2++), with a higher frequency in patients with primary nodal involvement. Disease-free survival (DFS) was significantly better in bcl2-negative/intermediate (bcl2-/+) cases as compared with bcl2++ cases (P = .0011). At 5 years, bcl2-/+ patients showed a DFS rate of 74%, in contrast to bcl2++ patients with a DFS rate of 41% (P = .002). Bcl2 was the strongest independent prognostic value in a multivariate analysis, with a relative risk (RR) of 3.0 in comparison to p53 expression and the clinical factors of the IPI. Overall survival (OS) was not significantly influenced by bcl2 protein expression. p53 protein expression was found in 13% of cases, with a higher frequency in patients with extensive disease. p53 expression did not influence the chance to achieve complete remission (CR) and survival. CONCLUSION: bcl2 protein is frequently expressed in LCL and is a strong independent prognostic factor for DFS. p53 expression is related with high tumor burden, but is not an independent risk factor for CR and survival.

Adult↗
PubMed1996

Retrospective Comparison of a Strategy of Primary Coronary Angioplasty versus Intravenous Thrombolytic Therapy for Acute Myocardial Infarction in a Community Hospital without Cardiac Surgical Backup.

Recent studies have demonstrated the benefit of primary percutaneous coronary angioplasty (PTCA) for the emergency treatment of acute myocardial infarction. We retrospectively examined our experience in performing primary PTCA in a community hospital without in-hospital surgical backup. Only highly experienced angioplasty operators participated, and patients were immediately transferred to a tertiary care referral hospital following primary angioplasty and stabilization. A total of 102 patients received PTCA at the community hospital during the study period. Forty received PTCA for cardiogenic shock or for rescue angioplasty. The remaining 62 patients (the Primary Angioplasty Group) were compared with a matched group of patients who received thrombolytic therapy during the same time period (the Thrombolytic Therapy Group). Angioplasty was angiographically successful in 96% and TIMI-3 grade blood flow was achieved in 85% of patients who received PTCA. There were no significant differences between the two groups in terms of in-hospital complications. The duration of hospital stay was significantly less in the Primary Angioplasty Group as compared with the Thrombolytic Therapy Group (median = 4 vs. 6 days, p = 0.005), as was the duration of intensive care unit stay (median 1 vs. 2.5 days, p = 0.001). Thus, under carefully controlled conditions, primary angioplasty for acute myocardial infarction in a community hospital without in-hospital cardiac surgery is an effective and more efficient alternative to thrombolytic therapy.

Journal Article↗
PubMed1995

Laboratory practices in reporting flow cytometry phenotyping results for leukemia/lymphoma specimens: results of a survey.

Laboratory directors who routinely utilize flow cytometry for at least part of their diagnostic evaluations in leukemias or lymphomas were surveyed by mail. The survey consisted of 12 questions about the flow cytometry procedures used by the laboratory in evaluating leukemias and lymphomas and on the format and content of their official report. It also requested an example of a typical leukemia/lymphoma report and solicited write-in comments about additional important aspects of using flow cytometry to evaluate leukemia and lymphomas not covered by the questionnaire. The goal of the survey, which was sponsored by the Clinical Cytometry Society (CCS), was to document what directors of flow cytometry laboratories currently consider to be the appropriate contents of a clinical leukemia/lymphoma phenotyping analysis and in what manner and detail they report such flow cytometry results to clinicians. The survey indicated that a large number of markers are routinely evaluated to phenotype leukemias (mean = 19) and lymphomas (mean = 16). Light scatter gating, using CD45/14 to monitor the gate selected, is currently employed by a 2:1 ratio over the next most population gating strategy (CD45 vs. 90 degrees LS). Peripheral blood, bone marrow, and lymphoid tissue constitute the majority of clinical specimens evaluated for leukemia and/or lymphoma. Two-color analysis, primarily for surface markers, is currently the standard method for flow cytometry measurements in routine diagnostic studies of leukemia and lymphoma. The official flow cytometry laboratory report is most commonly an individual-lab-generated, paper report form. A discussion of the potential benefits that might result from the development of improved computerized reporting software and from the increased use of antibody-defined, lineage gating is offered. A composite report format is presented that demonstrates the flow measurements and quality control data included in the best of the example clinical reports submitted as part of the survey and considered important by a majority of our survey respondents. The example report is intended to be a basis for further discussion within the flow cytometry community on whether minimum reporting standards for leukemia and/or lymphoma flow cytometry results can and should be developed.

Antigens, CD↗
PubMed1995

Right gastroepiploic-to-coronary artery bypass. The first decade of use.

BACKGROUND: The right gastroepiploic artery was first used by us as a coronary artery bypass graft (CABG) in June 1984 and has become an accepted alternative conduit for myocardial revascularization. METHODS AND RESULTS: We have now performed this operation in 126 patients (111 of whom were men) aged 32 to 78 years. The right gastroepiploic artery was used as a pedicle graft to the right main coronary artery in 25 patients, to its posterior descending branch in 90, to a left ventricular branch in 2, to branches of the circumflex system in 6, and to the left anterior descending artery in 1. Free (aortocoronary) gastroepiploic grafts were placed to circumflex branches in 2 patients. There were 2 hospital deaths (stroke, arrhythmia), and mean +/- SD postoperative stay was 7.5 +/- 2.0 days. All survivors were symptomatically improved and are functionally in New York Heart Association functional class I or II. There have been 3 late deaths (at 34, 50, and 84 months) in 2 to 120 months of follow-up (mean, 41.4 months). Angiography of bypass grafts and coronary arteries was performed in 44 patients at 7 days to 80 months postoperatively, providing direct evidence of gastroepiploic graft patency in 34 patients and strong indirect evidence in another 6; adequate data could not be obtained in 3 patients for technical reasons, and 1 graft was occluded. CONCLUSIONS: These short-term, intermediate, and long-term results demonstrate the suitability of the right gastroepiploic artery as a CABG. The use of the right gastroepiploic artery as a graft to coronary arteries on the posterior wall of the heart, in conjunction with one or both internal mammary arteries, has the potential to allow complete myocardial revascularization with viable arterial grafts.

Adult↗
PubMed1995

Confounding variables affecting in vitro fertilization success: a decade of experience.

PURPOSE: To evaluate etiology of infertility, female age, ovarian response and stimulation protocol in affecting in vitro fertilization (IVF) success. METHODS: Retrospective analysis was used. Computer records of all 5209 cycles initiated in 2391 couples from February 1, 1984 to December 31, 1993 were analyzed. RESULTS: There were 644 intrauterine, 24 solely ectopic and 7 heterotopic pregnancies. Pregnancy rates increased with number of embryos transferred with a significant increase still found between transfer of three or four embryos. Multiple gestations also increased in association with an increasing number of embryos transferred. Pregnancy rates per cycle did not decline with repeated cycles. Reduced pregnancy rates were associated with a primary diagnosis of male infertility. Covariates associated with a better pregnancy rate were younger age of the female partner or higher peak preovulatory serum estradiol. Routine administration of GnRH-agonist was associated with a reduced cycle cancellation rate, an increase in oocytes retrieved and an improved pregnancy rate. CONCLUSIONS: Couples with male infertility and increased female age should be counselled regarding the reduced prognosis for success.

Age Factors↗
PubMed1995

Antiviral effect of cyclopentenone prostaglandins on vesicular stomatitis virus replication.

Prostaglandins are potentially useful antiviral agents, however their mechanism of action is unclear. Recent evidence suggests that RNA transcription of vesicular stomatitis virus (VSV) is inhibited by prostaglandins (Bader and Ankel, J. Gen. Virol. 71, 2823-2832, 1990). Prostaglandins are known to have multiple effects on cells which may or may not be related to their antiviral action. We examined the effects of prostaglandins on cells and on VSV RNA polymerase in vitro to seek the mechanism of antiviral action. Actinomycin D inhibited cellular RNA synthesis but failed to block the antiviral activity of prostaglandins on VSV. Thus induction of host cell RNA transcription is not involved in the antiviral action. Neither modulation of the cellular glutathione level by prostaglandins nor formation of prostaglandin-glutathione conjugates was required for the antiviral action. The relative inhibition of VSV RNA polymerase in vitro by prostaglandins with different structures correlated to inhibition of VSV replication in infected cells. This result indicates that the same step in VSV replication is inhibited by prostaglandins both in the in vitro RNA polymerase assay and in the infected cell.

Animals↗
PubMed1995

Cumulative pregnancy rates and pregnancy outcome after in-vitro fertilization: > 5000 cycles at one centre.

Cumulative pregnancy rates and pregnancy outcome analysis are useful methods for advising an infertile couple of the probability of in-vitro fertilization (IVF) success. All 5209 IVF cycles in 2391 couples at University Hospital, London, Ontario, Canada, over 10 years were studied. Cumulative pregnancy rates were estimated using life table analysis. The Cox proportional hazards model was used to estimate the influence of covariates. Oocyte retrieval and embryo transfer were achieved in 84 and 64% of cycles initiated respectively. There were 644 intra-uterine and 24 ectopic pregnancies (13%/cycle initiated, 15%/oocyte retrieval and 20%/embryo transfer). Cumulative pregnancy rates following six cycles were: tubal 55%, idiopathic 65%, endometriosis 60%, multifactorial 63% and male 40%. There were 68 spontaneous abortions (10.6%) and three induced abortions for congenital anomalies. The multiple gestation rate was 22%. Caesarean section and preterm delivery rates were 35 and 20% respectively, due in part to the high proportion of multiple gestations. Of 15 deliveries which resulted in stillbirths and/or neonatal deaths, 12 were multiple gestations; 18 pregnancies (3.3%) were complicated by congenital malformations. No increases in congenital malformations or spontaneous abortions were identified. Cumulative pregnancy rates were lower in cases of male infertility. Success rates did not decline with successive IVF cycles. IVF is an evolving infertility treatment.

Birth Rate↗
PubMed1995

Male and female flowers of the dioecious plant sorrel show different patterns of MADS box gene expression.

Male and female flowers of the dioecious plant sorrel (Rumex acetosa) each produce three whorls of developed floral organs: two similar whorls of three perianth segments and either six stamens (in the male) or a gynoecium consisting of a fertile carpel and two sterile carpels (in the female). In the developing male flower, there is no significant proliferation of cells in the center of the flower, in the position normally occupied by the carpels of a hermaphrodite plant. In the female flower, small stamen primordia are formed. To determine whether the organ differences are associated with differences in the expression of organ identity genes, cDNA clones representing the putative homologs of B and C function MADS box genes were isolated and used in an in situ hybridization analysis. The expression of RAD1 and RAD2 (two different DEFICIENS homologs) in males and females was confined to the stamen whorl; the lack of expression in the second, inner perianth whorl correlated with the sepaloid nature of the inner whorl of perianth segments. Expression of RAP1 (a PLENA homolog) occurred in the carpel and stamen whorls in very young flower primordia from both males and females. However, as soon as the inappropriate set of organs ceased to develop, RAP1 expression became undetectable in those organs. The absence of expression of RAP1 may be the cause of the arrest in organ development or may be a consequence.

Amino Acid Sequence↗
PubMed1995

Further characterization of Chlamydia pneumoniae specific monoclonal antibodies.

Studies using monoclonal antibodies have demonstrated species-specific reactivities with Chlamydia pneumoniae. In this study, further characterization of C. pneumoniae specific monoclonal antibodies TT-205 and RR-402 and description of C. pneumoniae specific antibodies prepared against other isolates are presented. TT-205 and RR-402 were shown to neutralize infectivity. Neutralization in cell culture was specific and enhanced by complement. Attempts to characterize the reactive antigen by immunoblotting, immunoaffinity chromatography and radioimmunoprecipitation were unsuccessful, probably due to difficulties in solubilizing the immunoreactive epitope without denaturing it. Recognition of the determinant by the monoclonal antibodies is labile to physical and chemical treatments suggesting that the reactive epitope is conformational.

Animals↗
PubMed1995

Post-traumatic stress symptoms in children and parents following a school-based fatality.

In 1991 the roof blew off a Swindon Primary School. One child was killed. Two years later 19 of her classmates were interviewed. The parent who collected the child from school that day was also interviewed. Recalled levels of post-traumatic stress syndrome (PTSD) symptoms were assessed in both parent and child in the month following the incident. The children's symptom levels at 2 years were also assessed. Parents and children recalled significant post-traumatic stress reactions at 1 month. The level of symptoms in parents did not correlate with that of their own children.

Adolescent↗