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Biomedical subjects

G Walsh

Publications and source records attributed to G Walsh.

At least 19 recordsLinked to original sources

Giant coronary artery bypass graft pseudoaneurysm presenting as a haemothorax.

Coronary artery bypass graft pseudoaneurysms are rare. A case of a giant coronary artery pseudoaneurysm with probable intrapleural leakage and resulting haemothorax 14 years after coronary artery bypass surgery (CABG) is presented. The computed tomography (CT) and angiographic appearances are described. To our knowledge, this clinical presentation of a CABG pseudoaneurysm has not been described. Walsh, G. (2001). Clinical Radiology56, 74-75.

Aged↗

A suggested module detailing biopharmaceuticals suitable for inclusion in undergraduate applied biochemistry/biochemistry programs.

A 26 lecture module is outlined which details the biochemistry and biotechnology of biopharmaceutical substances. It is designed to equip students undertaking programs in applied biochemistry/biochemistry with an understanding of concepts, both academic and applied, directly relevant to working in the biopharmaceutical sector. In addition to the syllabus, a bank of relevant resource material is provided.

Journal Article↗

The management of superior sulcus tumors.

Lung cancers arising from the extreme apex of the lung-superior sulcus tumors (SST)-have distinct symptoms and signs at presentation and a characteristic appearance on imaging. However, in their early stages, these tumors are often missed by traditional anterior/posterior chest X-rays. Recent advances in computed tomography (CT) and magnetic resonance imaging (MRI) have made selection of patients with potentially resectable of SST more accurate. If mediastinoscopy reveals no mediastinal lymph nodes involved, the patient can be treated with surgery followed by radiation therapy with or without chemotherapy. If mediastinoscopy reveals microscopic mediastinal lymph node involvement, the patient can be treated with induction radiation therapy and concurrent chemotherapy followed by surgery. If mediastinoscopy reveals gross mediastinal lymph node involvement (N2), or if CT reveals N3 or T4 lesions, the patient can be treated with concurrent chemotherapy and radiation therapy to relieve symptoms; the outcome of such treatment appears to be better than that of sequential chemotherapy followed by radiation therapy. Whenever possible, to enhance the patient's quality of life, surgery should be considered to improve function and relieve pain.

Diagnostic Imaging↗

Multimodality therapy in inflammatory breast cancer: is there a place for surgery?

BACKGROUND: In many centres surgery is used as part of a combined modality approach to the treatment of inflammatory breast cancer (IBC). Nevertheless, its value is controversial given the high risk of metastatic relapse and poor overall prognosis. We have reviewed patients with true IBC prospectively treated at the Royal Marsden Hospital in chemotherapy trials to assess further the role of surgery as part of combined modality treatment. PATIENTS AND METHODS: Fifty-four patients who had responsive or stable disease to primary chemotherapy went on to have either radiotherapy alone (n = 35) or surgery plus radiotherapy (n = 19); the decision on surgery was based partly on clinician preference and partly on clinical response. RESULTS: The 35 patients undergoing radiotherapy alone had a median progression-free survival (PFS) of 16 months and median overall survival (OS) of 35 months. Twenty-four patients (69%) have relapsed with a total of twelve (34%) relapsing locally. In comparison, the 19 patients receiving both surgery and radiotherapy had a PFS of 20 months, and a median OS of 35 months. Fifteen patients (79%) have relapsed, eight (42%) of these locally. None of these differences were statistically significant. CONCLUSIONS: These results do not suggest a clinical advantage for surgery in addition to chemotherapy and radiotherapy for patients with IBC. They support the need for a prospective randomised trial to address this question.

Adult↗

Subsequent investigation and management of patients with intermediate-category and -probability ventilation-perfusion scintigraphy.

The authors wished to determine the proportion of patients with intermediate-category and intermediate-probability ventilation-perfusion scintigraphy (IVQS) who proceed to further imaging for investigation of thromboembolism, to identify the defining clinical parameters and to determine the proportion of patients who have a definite imaging diagnosis of thromboembolism prior to discharge from hospital on anticoagulation therapy. One hundred and twelve VQS studies performed at the Flinders Medical Centre over a 9-month period were reported as having intermediate category and probability for pulmonary embolism. Medical case notes were available for review in 99 of these patients and from these the pretest clinical probability, subsequent patient progress and treatment were recorded. Eight cases were excluded because they were already receiving anticoagulation therapy. In the remaining 91 patients the pretest clinical probability was considered to be low in 25; intermediate in 30; and high in 36 cases. In total, 51.6% (n = 47) of these patients (8% (n = 2) with low, 66% (n = 20) with intermediate, and 69.4% (n = 25) with high pretest probability) proceeded to CT pulmonary angiography (CTPA) and/or lower limb duplex Doppler ultrasound (DUS) evaluation. Of the patients with IVQS results, 30.7% (n = 28) were evaluated with CTPA. No patient with a low, all patients with a high and 46% of patients with an intermediate pretest probability initially received anticoagulation therapy. This was discontinued in three patients with high and in 12 patients with intermediate clinical probability prior to discharge from hospital. Overall, 40% of patients discharged on anticoagulation therapy (including 39% of those with a high pretest probability) had a positive imaging diagnosis of thromboembolism The results suggest that, although the majority of patients with intermediate-to-high pretest probability and IVQS proceed to further imaging investigation, CTPA is relatively underused in this group. Most patients with a high pretest clinical probability receive anticoagulation therapy irrespective of imaging findings, and less than half of all patients discharged from hospital on anticoagulation therapy have a positive imaging diagnosis of thromboembolism.

Angiography↗

Containment of simian immunodeficiency virus infection: cellular immune responses and protection from rechallenge following transient postinoculation antiretroviral treatment.

To better understand the viral and host factors involved in the establishment of persistent productive infection by primate lentiviruses, we varied the time of initiation and duration of postinoculation antiretroviral treatment with tenofovir (9-[2-(R)-(phosphonomethoxy)propyl]adenine) while performing intensive virologic and immunologic monitoring in rhesus macaques, inoculated intravenously with simian immunodeficiency virus SIVsmE660. Postinoculation treatment did not block the initial infection, but we identified treatment regimens that prevented the establishment of persistent productive infection, as judged by the absence of measurable plasma viremia following drug discontinuation. While immune responses were heterogeneous, animals in which treatment resulted in prevention of persistent productive infection showed a higher frequency and higher levels of SIV-specific lymphocyte proliferative responses during the treatment period compared to control animals, despite the absence of either detectable plasma viremia or seroconversion. Animals protected from the initial establishment of persistent productive infection were also relatively or completely protected from subsequent homologous rechallenge. Even postinoculation treatment regimens that did not prevent establishment of persistent infection resulted in downmodulation of the level of plasma viremia following treatment cessation, compared to the viremia seen in untreated control animals, animals treated with regimens known to be ineffective, or the cumulative experience with the natural history of plasma viremia following infection with SIVsmE660. The results suggest that the host may be able to effectively control SIV infection if the initial exposure occurs under favorable conditions of low viral burden and in the absence of ongoing high level cytopathic infection of responding cells. These findings may be particularly important in relation to prospects for control of primate lentiviruses in the settings of both prophylactic and therapeutic vaccination for prevention of AIDS.

Adenine↗

Clinical and radiological characteristics of lung disease in inflammatory bowel disease.

The pulmonary associations of inflammatory bowel disease (IBD) are poorly characterized. The clinical, physiological and high-resolution computed tomographic thorax characteristics of the lung disease in patients with IBD presenting with respiratory symptoms are described. Detailed clinical information was obtained and standard pulmonary physiological tests and thorax high-resolution computed tomography performed on 14 patients with ulcerative colitis (UC) and three with Crohn's disease (CD), 10 male, aged 38-83 yrs. Respiratory symptoms had been present for 2-50 yrs and extraintestinal manifestations were present in three (17.6%). Normal pulmonary physiology (six patients) was associated with the high resolution computed tomographic changes of bronchiectasis, mosaic perfusion and air trapping suggestive of obliterative bronchiolitis and a pattern of centrilobular nodules and branching linear opacities ("tree in bud" appearance) suggestive of either cellular bronchiolitis or bronchiolectasis with mucoid secretions. Bronchiectasis was found in 13 patients (11 UC, 2 CD), 11 had air trapping and five had a "tree in bud" appearance on computed tomography. One patient had a predominantly peripheral reticular pattern at the lung bases similar to that found in cryptogenic fibrosing alveolitis and one patient had a mixed reticular and ground-glass pattern in the midzones with a patchy distribution in the central and peripheral portions of the lungs with air trapping. Eleven patients (three with alveolitis) exhibited a clinical and/or physiological response to steroids. Pulmonary abnormalities in ulcerative colitis and Crohn's disease can present years after the onset of the bowel disease and can affect any part of the lungs. Early recognition is important as they can be strikingly steroid-responsive.

Adult↗

The depth, contour and angle of the glazing grooves of spectacle frames: don't blame the glazer?

The groove of a spectacle frame is responsible for lens retention. It also tends to fill with unsightly dirt which cannot be readily removed by our patients. The results of this investigation would suggest that both loose spectacle lenses and dirt accumulation may often be due to poor quality control in the frame industry. The data also suggests that unwanted stress may be present in both frames and lenses due to non-optimal groove shape.

Equipment Design↗

Assessment methods for alcohol consumption, prevalence of high risk drinking and harm: a sensitivity analysis.

BACKGROUND: There are no standardized ways to assess alcohol consumption in epidemiological studies. The main objective of the present study was to compare three widely used methods for assessing alcohol consumption with respect to resulting prevalence estimates for high risk drinking and harm as defined by morbidity and mortality indicators. METHODS: A within-subjects design was used to compare a quantity frequency, a graduated frequency, and a weekly drinking recall measure. Data consisted of a representative sample of 3961 adult residents of the province of Ontario, Canada, who participated in a multi-wave cross-sectional survey between 1990-1994. Cross-tabulation, Spearman correlation, and standard methodologies for prevalence-based cost-of-illness studies were used. RESULTS: The graduated frequency measure consistently yielded higher estimates of the prevalences of high risk drinking and harm. Differences were marked on all indicators, but were most pronounced for harmful drinking as defined by consuming an average of >60 g pure alcohol per day for males, and >40 g per day for females. Prevalence estimates of harmful drinking were almost five times higher for graduated frequency versus weekly drinking measures, and almost three times higher for graduated frequency versus quantity frequency measures. CONCLUSIONS: The characteristics of different measures of alcohol consumption should be considered in future research in epidemiology.

Adult↗

Heavy drinking and problems among wine drinkers.

OBJECTIVE: The purpose of this study was to see whether adults who drank wine exclusively would have lower quantity-frequency scores, less intoxication and fewer alcohol-related problems than those who drank other types of alcohol. METHOD: Data were analyzed from a national survey of the use of alcohol and other drugs conducted in Canada in 1994 (N = 8,758). RESULTS: Wine only drinkers were less often intoxicated than other drinkers. They also had lower quantity-frequency scores and reported fewer alcohol-related problems than other drinkers. These results were maintained when age, gender and quantity-frequency were taken into account. CONCLUSIONS: Wine only drinkers drink less than other types of drinkers and have fewer problems. As wine is often drunk with meals there is probably more social control over drinking. Also, since wine drinkers drink with meals their blood alcohol concentrations may be lower.

Adolescent↗

Overexpression of cdc25A and cdc25B is frequent in primary non-small cell lung cancer but is not associated with overexpression of c-myc.

Cyclin-dependent kinases can be activated by cdc25, which removes inhibitory phosphates from tyrosine and threonine residues. At least three cdc25 genes (cdc25A, cdc25B, and cdc25C) have been identified in humans. Accumulating evidence indicates that cdc25A and cdc25B possess oncogenic properties. Recently, overexpression of cdc25A and of cdc25B was found in many breast and head and neck cancers. To determine potential roles of cdc25s in non-small cell lung cancer (NSCLC), we analyzed primary tumors and corresponding normal lung tissues from 40 patients with NSCLC for relative expression levels of these genes by multiplex reverse transcription PCR (RT-PCR). cdc25A was overexpressed in 60% (24 of 40) of the tumors and cdc25B in 45% (18 of 40) of the tumors, whereas cdc25C was not overexpressed in any of the tumors analyzed. Because c-myc can increase cdc25A and cdc25B expression, it may be a factor in cdc25 overexpression. We found that c-myc was overexpressed in only 18% (7 of 40) of the tumors. We found no association between overexpression of c-myc and cdc25A or cdc25B. We also investigated whether the cdc25B gene was amplified in NSCLC and found this was true in 40% (8 of 20) of the tumors tested. However, this amplification was not correlated with gene expression status. Interestingly, among 24 tumors with cdc25A overexpression and 18 with cdc25B overexpression, 42% (10 of 24) and 44% (8 of 18) were poorly differentiated histological type. In contrast, well or moderately differentiated tumors had lower frequencies of cdc25A and cdc25B overexpression [19% (3 of 16) and 23% (5 of 22), respectively]. These data indicate that overexpression of cdc25A and cdc25B is frequent and that it may play an important role in NSCLC. However, it is unlikely that this overexpression is caused by c-myc stimulation or cdc25B gene amplification.

Adenocarcinoma↗

Reduced apoptosis and proliferation and increased Bcl-2 in residual breast cancer following preoperative chemotherapy.

Experimental laboratory data suggest that tumour growth is a balance between apoptosis and proliferation and that suppression of drug-induced apoptosis by oncogenes such as bcl-2 may be an important cause of intrinsic chemoresistance. The aims of this study were to assess the in vivo relationship of apoptosis to proliferation and Bcl-2 protein in human breast tumours both prior to chemotherapy and in the residual resistant cell population at the completion of treatment. We examined apoptotic index (AI), Ki67 and Bcl-2 protein expression in the tissue of 40 patients with operable breast cancer immediately before ECF preoperative chemotherapy, and in 20 of these patients with residual tumour, at the completion of treatment. There was a significant positive association between AI and Ki67 both before and after chemotherapy, and in their percentage change with treatment. In the residual specimens AI and Ki67 were significantly reduced compared with pre-treatment biopsies, while Bcl-2 expression showed a significant increase. No differences were seen in the pre-treatment levels of any of the variables measured between patients obtaining pathological complete response and those who did not, although numbers were small. These data suggest that apoptosis and proliferation are closely related in vivo. It is possible that the phenotype of reduced apoptosis and proliferation, and increased Bcl-2 may be associated with breast cancer cells resistant to cytotoxic chemotherapy, although this can only be proven by assessing larger numbers of patients in relation to pathological response.

Adult↗

Clinical prognostic and predictive factors for primary chemotherapy in operable breast cancer.

PURPOSE: This study aimed to identify clinical factors that are of prognostic significance or that predict for subsequent treatment outcome in patients with large operable breast cancer treated with primary chemotherapy (PCT) at our institution. METHODS: One hundred eighty-five patients received the following regimens: CMF or MMM (76 patients), ECF (75 patients), AC or FEC (34 patients), followed by surgery, with radiotherapy (RT) given to those with breast conservation. A number of common clinical variables were assessed in relation to local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS). RESULTS: Clinical responders had improved DFS (P = .009) and OS (P = .08) compared with nonresponders. There was no association between clinical or pathologic complete remission (CR) and survival. Pretreatment clinical axillary node positivity was a significant predictor of worsened DFS (P = .0001), OS (P = .0001), and LRFS (P = .03). Patients remaining clinically node-positive postchemotherapy had an inferior outcome compared with those becoming node-negative (DFS, P = .03; OS, P = .03) but pathologic axillary node status was not shown to predict for survival. Twenty-nine patients in clinical CR following PCT who electively did not have surgery and were treated with RT alone had significantly increased local recurrence rate compared with partial responders having surgery and RT (P = .02). There were no differences in DFS or OS between these groups. On multivariate analysis, clinical axillary node status was the only independent predictor of OS and DFS, and LRFS. CONCLUSION: Pretreatment and posttreatment clinical axillary node status is a major predictor of outcome following PCT. Complete clinical response does not define a more favorable subgroup compared with those not obtaining CR.

Adult↗

Randomized phase II trial of infusional fluorouracil, epirubicin, and cyclophosphamide versus infusional fluorouracil, epirubicin, and cisplatin in patients with advanced breast cancer.

PURPOSE: We previously developed an inpatient regimen that consisted of infusional fluorouracil (5-FU), epirubicin, and cisplatin (ECisF), with a response rate of 86% in advanced breast cancer. The current phase II 2:1 randomized study investigated whether cyclophosphamide can be substituted for cisplatin (ECycloF) to reduce toxicity and allow the regimen to be administered on an outpatient basis without loss of efficacy. PATIENTS AND METHODS: Ninety-six women (median age, 49 years; range, 28 to 73) with breast cancer (59 metastatic, 37 locally advanced) received continuous infusional 5-FU (200 mg/m2/d via Hickman line) and six cycles of epirubicin (60 mg/m2 every 21 days) with either cyclophosphamide 600 mg/m2 every 21 days (38 metastatic, 24 locally advanced) or cisplatin 60 mg/m2 every 21 days (21 metastatic, 13 locally advanced). There were no significant differences in patient characteristics between these groups. RESULTS: ECycloF was better tolerated than ECisF in terms of lethargy (P = .005), stomatitis (P = .008), plantar palmar erythema (P = .02), constipation (P < .001), thrombosis (P = .0014), and nausea and vomiting (P = .05). Although there was a trend toward more anemia and leukopenia with ECisF (P =. 1), there was no significant difference in the rates of infection. Efficacy was comparable in terms of overall response (69% v 68%), complete response (CR; 13% v 15%), and median progression-free survival (9 v 8 months). CONCLUSION: ECycloF is an outpatient regimen with a lower incidence of severe nonhematologic toxicity than inpatient ECisF; it has comparable efficacy and is considerably more economical.

Adult↗

Contrast and glare sensitivity in diabetic patients with and without pan-retinal photocoagulation.

Patients with diabetes mellitus often have ophthalmic dysfunction, as diabetic eye disease can affect the majority of the ocular structures. The present study investigated contrast sensitivity (experiment 1) and glare sensitivity (experiment 2) using Pelli-Robson and Bailey-Lovie charts in normal and diabetic patients with a range of degrees of ischaemic retinopathy (n = 220). Contrast sensitivity thresholds reduced and glare sensitivity progressively increased throughout the range from normal to advanced stages of diabetic eye disease. However, the reduction in contrast sensitivity between adjacent groups was not significant (P > 0.10). Conversely, glare sensitivity was found to be greater in those diabetic patients who had received laser treatment (P = 0.001). The potential use of both tests is discussed.

Adult↗