Biomedical subjects

M C Robinson

Publications and source records attributed to M C Robinson.

At least 37 records · Page 2Linked to original sources

PubMed1996

Primary choriocarcinoma of the urinary bladder: a case report.

We present a 37-year-old patient with primary choriocarcinoma arising in the urinary bladder, who received 5 months of intensive chemotherapy with a very good response. He died of a pulmonary embolus before his treatment could be completed. A post-mortem examination revealed extensive necrotic nodules in the lungs and brain. There was only one small focus of viable tumour in the brain. There was no residual tumour in the bladder, and no testicular tumours or scars fulfilling the criteria for a true extragonadal teratoma. It is likely that the origin of the bladder choriocarcinomas is from metaplasia/de-differentiation of a transitional cell carcinoma to the level of trophoblast. Lesser degrees of differentiation producing functional changes in the carcinoma cells with secretion of beta hCG without structural changes are much more common.

Adult↗

PubMed1996

bcl-2 overexpression combined with p53 protein accumulation correlates with hormone-refractory prostate cancer.

Seventy-seven men with histologically proven and newly diagnosed prostate cancer we investigated for the presence of bcl-2 protein overexpression and p53 protein accumulation 1 immunohistochemistry. Forty-five men had evidence of locally advanced and metastatic disease and we treated by means of hormone manipulation. Twenty-eight patients either failed to respond to initial hormone manipulation or relapsed within 37 months from diagnosis (median 20 months). Of the 77 cancers, 37 (48% showed bcl-2 overexpression at diagnosis. Twenty-seven of those were treated with androgen ablation and 2 (74%) had hormone-refractory disease (P = 0.0128). Twenty-three of 77 men (29.8%) had nuclear staining for p53 protein. Twenty-one of those were treated with hormone manipulation and 14 (66.6%) showed hormone resistance (P = 0.0012). Seventeen patients had both bcl-2 overexpression and p53 protein accumulation, 16 of whom were hormonally treated, with 13 (81.2%) having hormone-refractory disease (P < 0.0001). These findings suggest that the combined detection of p53 protein accumulation and bcl-2 overexpression may be useful in predicting hormone resistance in prostate cancer. By deregulating programmed cell death, alteration in these genes may prevent patients from responding to androgen ablation, or allow them to escape hormonal control of the disease.

Adenocarcinoma↗

PubMed1996

A systematic study of hypothermic lung preservation solutions: Euro-Collins solution.

BACKGROUND: Testing lung function after preservation is difficult because a suitable model is still lacking; thus, the effectiveness of different solutions for lung preservation has not been confirmed. This study tested the effectiveness of Euro-Collins solution alone for hypothermic preservation of rat lungs. METHODS: A living rat perfusion model was used, which allowed more than 5 hours of continuous perfusion for isolated lung function studies. Group 1 lungs (control, n = 8) were tested without preservation. In groups 2 through 6 (n = 8 lungs each), the lungs were flushed with 4 degrees C Euro-Collins solution and preserved for 4, 6, 8, 12, and 24 hours, respectively. Lung function studies were carried out after preservation. RESULTS: In groups 1 and 2, pulmonary arterial blood flow and pulmonary venous oxygen tension were higher and pulmonary resistance was lower than in the other groups. Airway pressure and resistance were lowest in group 1. Lungs in groups 5 and 6 demonstrated the worst function, but the lung tissue wet to dry ratio was higher only in group 6. CONCLUSIONS: At 4 degrees C, Euro-Collins solution can effectively preserve rat lungs for 4 hours. Six to 8 hours of preservation resulted in depressed lung function. More than 12 hours of preservation resulted in uniformly deficient lung function, rendering the lungs unsuitable for transplantation.

Airway Resistance↗

PubMed1995

Tc-99m MAA lung perfusion scintigraphy performed before and after pulmonary embolectomy for saddle-type pulmonary embolism.

A 58-year-old man had shortness of breath, hypotension, and decreased partial pressure of oxygen (PO2) on the eighteenth day after undergoing craniotomy for a meningioma. Tc-99m MAA pulmonary perfusion scintigraphy showed little perfusion to the right lung and left lower lung and multiple perfusion defects in the left upper lung. Although the results of concurrent chest radiography were negative for pulmonary infiltrates, pulmonary angiography demonstrated a saddle-type embolism. The patient underwent emergency pulmonary artery embolectomy to remove blood clots and organized thromboemboli from the main pulmonary artery and the right and left pulmonary arteries. The patient's postoperative course was uneventful, and a second Tc-99m MAA lung perfusion scan demonstrated marked improvement in lung perfusion.

Embolectomy↗

PubMed1995

Minimally invasive coronary artery bypass grafting: a new method using an anterior mediastinotomy.

The benefit of internal mammary artery (IMA) grafting as a long-lasting intervention for coronary artery disease is well recognized. However, largely because they are less invasive, catheter based alternatives are frequently chosen, particularly to treat single or double vessel disease. To retain the advantages of the IMA graft, and to offset the invasiveness of conventional coronary artery bypass grafting, we developed a new minimally invasive method using an anterior mediastinotomy for treating left anterior descending (LAD) or right coronary artery disease, or both. Feasibility studies using 16 pigs and a human cadaver led to approval by the Institutional Review Board for use of this procedure to treat six patients (four men, two women; mean age, 63.8 +/- 13.6 [SD] yrs) who granted informed consent. Pedicle dissection of the IMA, using video assisted thoracoscopy if necessary, was made through a 2- to 3-inch horizontal anterior mediastinotomy. The underlying LAD artery was grafted during femoral vessel cardiopulmonary bypass, with cooling to 30 degrees C, induced ventricular fibrillation, and left ventricular venting if required. Transesophageal echocardiography performed after bypass showed that two patients maintained normal wall motion and four had improvement from the original impairment. One patient suffered a recurrence of angina 4 weeks after the procedure; recatheterization showed an acutely angled IMA, subsequently corrected by balloon angioplasty. The results of follow-up dobutamine echocardiographic stress tests were negative in all patients. With this minimally invasive approach, the procedure should provide the benefits of IMA grafting with shorter hospital stay, more rapid recovery, and less overall cost.

Aged↗

PubMed1994

Cholesterol-lowering effect of barley bran flour and oil.

OBJECTIVE: To compare the effects of adding barley bran flour and a barley oil extract to a fat-modified diet on serum lipids in persons with hypercholesterolemia. DESIGN: The basic design of the study was a randomized, 30-day intervention trial. It included a neutral-fiber control group and a 1-week preintervention period for the collection of baseline data. SUBJECTS: The subjects were 79 men and women with hypercholesterolemia. Subjects had a mean age of 48.2 years, and all completed the study. INTERVENTION: All participants were instructed to follow the National Cholesterol Education Program (NCEP) step 1 diet and were randomly assigned to one of three treatment groups: 20 g added cellulose, 3 g added barley oil extract, or 30 g added barley bran flour. MAIN OUTCOME MEASURES: Total serum cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and very-low-density lipoprotein cholesterol were measured, along with serum triglycerides, before the intervention, at week 1, at week 3, and at the end of the intervention. STATISTICAL ANALYSES PERFORMED: Student's paired t test was used to detect significant changes within each treatment group from baseline to the end of the 30-day intervention. In addition, Pearson's correlation coefficients were used to detect significant correlations between the variables measured. RESULTS: Addition of barley bran flour significantly (P = .0001) decreased total serum cholesterol (-0.60 mmol/L) as did addition of barley oil (-0.50 mmol/L; P = .002) after 30 days of intervention. Similarly, LDL-C decreased 6.5% with addition of barley bran flour (P = .036) and 9.2% with addition of barley oil (P = .003). Total serum cholesterol or LDL-C of the cellulose control group did not decrease significantly over the same period. HDL-C decreased significantly in the cellulose control group and the barley bran flour group (-0.15 mmol/L, P = .012, and -0.15 mmol/L, P = .006, respectively), but not in the barley oil group. CONCLUSION: We conclude that addition of barley bran flour or barley oil enhances the cholesterol-lowering effect of the NCEP step 1 diet in individuals with hypercholesterolemia.

Adult↗

PubMed1994

c-jun oncogene expression in transitional cell carcinoma of the urinary bladder.

OBJECTIVE: To investigate c-jun oncoprotein expression in transitional cell carcinomas (TCCs) of the urinary bladder and to determine its relationship to tumour grade and stage, and to the expression of epidermal growth factor receptor (EGFR), c-erbB-2 and p53 oncoproteins. MATERIALS AND METHODS: The expression of c-jun was studied using immunohistochemistry in a series of 48 TCCs of known EGFR, c-erbB-2 and p53 status. RESULTS: Forty-four of 48 (92%) tumours showed c-jun specific nuclear immunoreactivity of variable intensity. The intensity of c-jun immunostaining was significantly related to tumour stage (P = 0.009) and EGFR status (P = 0.01). There was no correlation between c-jun oncoprotein expression and c-erbB-2 or p53 immunoreactivity. c-jun expression was not related to clinical outcome in terms of patient survival or rate of tumour recurrence. CONCLUSION: The c-jun oncoprotein is expressed in the majority of TCCs of the urinary bladder. There is a positive association between intense c-jun immunoreactivity and muscle invasive growth, and EGFR positivity in TCCs.

Aged↗

PubMed1994

Abnormalities in p53 and DNA content in transitional cell carcinoma of the bladder.

OBJECTIVE: To determine if transitional cell tumours of the bladder which contain mutations in the p53 gene have alterations in their DNA content. MATERIALS AND METHODS: In 33 transitional cell tumours of the bladder, DNA content was determined by flow cytometry and compared with expression of mutant p53 as assessed by immuno-histochemistry. RESULTS: Abnormal DNA content was associated with increased staining for p53 (P < 0.05), high tumour stage (P < 0.001) and increased histological grade (P < 0.01). Although positive staining for p53 was frequently associated with abnormal DNA content, a significant number of non-diploid tumours stained negatively for mutant p53. CONCLUSION: These data demonstrate that increased staining for p53 is associated with abnormalities in DNA content suggesting that mutation of the p53 gene is associated with an increased rate of chromosomal abnormalities and an increased rate of cell proliferation.

Carcinoma, Transitional Cell↗

PubMed1994

P53 expression, ploidy and progression in pT1 transitional cell carcinoma of the bladder.

OBJECTIVE: To investigate a potential role for overexpression of the p53 protein in the identification of pT1 bladder tumours destined to progress. PATIENTS AND METHODS: The protein expression of the tumour suppressor gene p53, nuclear ploidy and tumour grade were studied in 25 patients with pT1 bladder tumours. Follow-up data was available for 21 tumours over a 10 year period. p53 expression was determined by immuno-histochemistry on paraffin embedded sections and flow cytometry was performed on cell suspensions derived from the same blocks. RESULTS: Ten of 21 (48%) tumours progressed to muscle invasive disease. Nuclear staining for the protein was seen in 16 (64%) tumours and of these nine (56%) progressed. All tumours with abnormal DNA content and all high grade tumours demonstrated overexpression of p53. Significantly more patients with high levels of p53 expression (> 10% nuclear staining) progressed compared with tumours with less than 10% of nuclei staining (P = 0.007). However, grade was the most specific predictor of progression (100%), with all grade 3 tumours progressing and grade was also the most significant prognostic indicator in terms of survival (P = 0.025). CONCLUSION: Tumour grade is likely to remain as the most useful aid to management decisions in pT1 bladder tumours.

Aged↗

PubMed1993

Barley bran flour accelerates gastrointestinal transit time.

The effect of barley bran flour on colon physiology was studied in 44 volunteers. Twenty-two subjects followed the National Cholesterol Education Program (NCEP) step 1 diet supplemented with 20 g cellulose and the other 22 followed the NCEP diet supplemented with 30 g barley bran flour. To measure gastrointestinal transit time, subjects ingested 20 polyethylene pellets impregnated with barium sulfate in two gelatin capsules. Subjects collected fecal samples for 5 days during the baseline period and again during the period of fiber supplementation. Each stool sample was radiographed, and the number of recovered markers was used to calculate mean transit time. Daily fecal weights were recorded and dry weights were determined. The group that consumed barley bran flour significantly decreased transit time by 8.02 hours from baseline, whereas the group that consumed cellulose increased transit time by 2.95 hours from baseline. Similarly, cellulose supplementation did not result in increased fecal weight, whereas daily fecal weight increased significantly by 48.6 g with supplementation with barley bran flour. This study shows that barley bran flour accelerates gastrointestinal transit and increases fecal weight.

Adult↗

PubMed1993

Ischemic heart disease in the elderly: the role of coronary angioplasty and coronary artery bypass grafting.

Management of ischemic heart disease in the elderly is complex. Invasive therapies such as percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG) are associated with significant morbidity and mortality. The short-term advantage of PTCA is that its associated noncardiac morbidity and mortality are less than that of CABG, particularly in the incidence of stroke. Unfortunately, PTCA revascularization is less complete and less durable than CABG revascularization. The advantages of CABG are that cardiac revascularization is more complete, the result is more durable, and long-term results are improved over those of PTCA. Conversely, the initial morbidity and mortality are higher for CABG and are adversely affected by factors such as recent myocardial infarction, lung disease, and renal failure. We provide an overview of the results and outcomes of PTCA and CABG in the elderly, as well as suggestions for management.

Activities of Daily Living↗

PubMed1991

Surgical correction of the Wolff-Parkinson-White syndrome.

The results of corrective surgery in 75 consecutive patients with Wolff-Parkinson-White (WPW) syndrome are reported. There were 47 male and 28 female patients with a median age of 27 years. Intraoperative mapping disclosed 88 accessory pathways, of which 83 were successfully divided at the primary operation without mortality. Two patients underwent successful reoperation at three days and two years respectively. Patient success rates were 93% and 96% for first and total operations. Complications, usually minor, occurred in 20 patients, including permanent pacemaker implantation in two. Surgical correction of WPW syndrome is recommended as a safe alternative to lifelong medical treatment.

Adolescent↗

PubMed1991

Results of Medical Research Council phase II study of low dose cisplatin and methotrexate in the primary treatment of locally advanced (T3 and T4) transitional cell carcinoma of the bladder.

A series of 49 previously untreated patients with category T3 or T4 bladder cancer underwent treatment with low dose methotrexate and cisplatin; 44 patients were eligible for assessment of response. Complete response (CR) was seen in 5 patients (11%) and partial response in 15 (34%) (overall response rate 45%). Treatment was reasonably well tolerated with no major morbidity and no treatment-related deaths. After a median follow-up of 3.5 years, the 1-year and 2-year survival rates were 70 and 30% respectively. Ten patients remain recurrence-free without having received "definitive local therapy" (cystectomy and/or radiotherapy) at follow-up extending from 20 to 50 months.

Adult↗

PubMed1991

Operations for Wolff-Parkinson-White syndrome.

Forty-six patients with symptomatic tachycardia underwent operations to divide 55 atrioventricular accessory pathways. Mean age was 29 years (range 11 to 63). Ten patients (22%) had associated cardiac disease, including two with a congenital diverticulum of the coronary sinus and six (13%) who had concomitant surgical procedures. A bipolar hand-held electrode was used in 22 operations, and simultaneous multisite mapping in the last 24 operations. Ten patients (22%) had multiple accessory pathways. A modified endocardial approach was used. The overall patient success rate was 93% with 91% to 93% of accessory pathways successfully divided. The perioperative morbidity was 17%. There were two reoperations. There were no early or late deaths. Patients have been followed up for a mean of 16 months. There were five recurrences of preexcitation (two early, three late). Two of these patients (both with a congenital diverticulum of the coronary sinus) had reoperation. One patient had late recurrence of atrial fibrillation. Operation for the Wolff-Parkinson-White syndrome has a high probability of success with a low operative risk.

Adolescent↗

PubMed1990

Effects of verapamil and carbon monoxide on blood pressure and heart mass in the spontaneously hypertensive rat.

Studies were carried out to examine the relationship between blood pressure lowering using the Ca2+ channel blocker verapamil, and regression of ventricular hypertrophy, in the spontaneously hypertensive rat (SHR). Untreated male SHR showed rapidly developing hypertension (systolic pressure 194 +/- 2 mm Hg, 109 days of age) and moderate ventricular hypertrophy. Verapamil (Calan-SR, G.D. Searle Co.) treatment for 30 days at maximum doses of 18.7 and 49.9 mg/kg per day supplied in the food, lowered blood pressure maximally 37 mm Hg. The drug had no effect on heart rate. Decrease in the mass of the left ventricle plus interventricular septum was positively correlated with the verapamil-induced decrease in blood pressure (r = 0.69, P less than 0.001). SHR exposed continuously to 500 ppm carbon monoxide (CO) for 30 days showed a similar decrease in blood pressure (33.0 mm Hg). Such SHR, however, displayed increases in mass of the left ventricle plus septum and right ventricle, and of hematocrit, nearly identical to same age Sprague-Dawley rats similarly exposed to CO. Neither verapamil nor CO treatment altered myocardial water content. The results suggest that a modest lowering of blood pressure with verapamil in the SHR produces a relatively rapid decrease in left ventricular mass. It also shows that even when afterload is reduced in the SHR, as with CO, substantial ventricular hypertrophy develops, probably because of augmented preload, and that it is comparable to that produced in non-hypertensive rats.

Animals↗

PubMed1990

Bladder carcinosarcomas: three cases with diverse histogenesis.

Carcinosarcomas of the bladder are rare. We describe three such tumours, including an apparently unique case in which the components comprised liposarcoma and poorly-differentiated transitional cell elements. A second example included chondrosarcomatous elements. These two tumours showed architectural and immunocytochemical features which suggested that they had originated as carcinomas but had subsequently differentiated along both epithelial and mesenchymal pathways. The third tumour contained both carcinoma and osteosarcoma and may represent a collision tumour.

Aged↗

PubMed1990

Cell cycling in bladder carcinoma determined by monoclonal antibody Ki67.

Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information.

Antibodies, Monoclonal↗

PubMed1990

In vitro antimicrobial susceptibilities of 349 methicillin-resistant Staphylococcus aureus isolates from veterans.

Three hundred and forty-nine methicillin resistant Staphylococcus aureus (MRSA) isolates from veterans were tested (by disc agar diffusion) for their in vitro activity against 18 antimicrobial agents. At least 90% of the isolates were susceptible to bacitracin, nitrofurantoin, hydrogen peroxide, novobiocin, netilmicin and vancomycin. We feel that the aminoglycoside, netilmicin, might provide an alternative agent (to intravenously administered vancomycin) for treating multiply-antimicrobial resistant MRSA. In addition, hydrogen peroxide exhibited very good activity against the test isolates and may have some use as a topical agent for reduction of MRSA on skin and some mucous membranes. This study suggests that further evaluation of netilmicin and hydrogen peroxide (topical only) might be useful.

Anti-Bacterial Agents↗