PubMed Health⌕ Search

Biomedical subjects

W F Miles

Publications and source records attributed to W F Miles.

At least 19 recordsLinked to original sources
PubMed1999

A lack of evidence for down-modulation of CD3 zeta expression in colorectal carcinoma and pregnancy using multiple detection methods.

Loss of the T cell receptor-associated CD3 zeta chain has been proposed as a possible mechanism of the acquired immunosuppression in both tumour-bearing hosts, and in symptomatic patients with HIV infection. However, other reports suggest that the zeta-chain loss may in part be caused by protease activity of contaminating phagocytes ex vivo. Using flow cytometry and Western blot analysis on highly purified T cells, and ensuring adequate addition of protease inhibitors, we have studied the expression of CD3zeta on peripheral blood T cells from patients with colorectal carcinoma, and compared these with normal controls, and pregnant donors, as a further example of an immunocompromised state. Immunohistochemistry was performed on tumour sections from patients with colorectal carcinoma to measure CD3zeta expression in tumour infiltrating T cells, and compared with normal mucosa and tonsil. Using these three approaches, our data provide no evidence for downregulation of CD3zeta chain expression either in colorectal carcinoma or pregnancy and suggest that this explanation is unlikely to fully account for the reduced T cell function associated with these conditions in all patients.

Adenocarcinoma↗
PubMed1996

Technique of laparoscopic splenectomy with a powered vascular linear stapler.

The spleen may be removed by a laparoscopic technique, although the benefits and associated morbidity of this approach are unknown. This study reports a series of 28 consecutive patients (15 women; median age 39 (range 17-84) years) considered for laparoscopic splenectomy, because of idiopathic thrombocytopenia in 14, human immunodeficiency virus-related thrombocytopenia in seven, autoimmune haemolytic anaemia in four, lymphoma in two and chronic lymphocytic leukaemia in one. In 23 cases dissection was completed laparoscopically, with the patient in the right lateral position, using a four-cannula technique. Vascular isolation was achieved with an Endo-GIA (powered vascular linear stapler). The spleen was removed by morselation within a retrieval bag (18 patients) or via either a Pfannenstiel or subcostal incision (five). The last 14 procedures have all been completed successfully in a mean operating time of 105 min with discharge from hospital within a median of 3 days. One patient developed a clinically apparent deep venous thrombosis 23 days after operation, for which he required readmission. Elective laparoscopic splenectomy is a feasible although technically demanding operation which may be performed safely and without associated mortality by surgeons experienced in laparoscopic techniques.

Adolescent↗
PubMed1995

Presentation of endometriosis to general surgeons: a 10-year experience.

The presentation and management of 24 patients with endometriosis (median age 34 (range 21-68)years) presenting to general surgeons over a period of 10 years (1985-1994) was reviewed. Patients presented with an abdominal wall swelling related to a previous Pfannenstiel incision (seven patients), umbilical swelling (four), inguinal canal swelling (two), incidentally following appendicectomy (five), terminal ileal obstruction (two), rectal bleeding (two) and urinary symptoms (two). Endometriosis was not suspected in most patients but was confirmed by surgical excision or resection with minimal morbidity. No recurrence occurred during a median follow-up of 53 (range 9-113) months. Endometriosis is a disease rarely seen by general surgeons and is often diagnosed incidentally or on histological examination. Cyclical symptoms associated with menstruation are present in 50 per cent of patients and should suggest the diagnosis in those presenting with scar-related and/or subcutaneous swellings. Simple excision or resection of the presenting lesion provides adequate treatment but, since pelvic endometriosis may be present, referral to a gynaecologist is recommended in every case.

Abdominal Muscles↗
PubMed1995

Raised carcinoembryonic antigen level as an indicator of recurrent disease in follow up of patients with colorectal cancer.

BACKGROUND: Serum carcinoembryonic antigen level is raised in 80% of patients undergoing colonic resection for cancer. Subsequent elevation in the follow-up period may precede signs and symptoms as an indicator of recurrent disease. there is little evidence that "classical" follow up of patients in the general surgical outpatient clinic improves either survival or quality of life. Regular carcinoembryonic antigen level estimation requested by the general practitioner, allied to day-case colonoscopic surveillance may be a more rational approach. AIM: A study was undertaken to investigate the relationship between raised carcinoembryonic antigen level and the recurrence of colorectal cancer in patients following a curative primary resection. METHOD: Retrospective analysis was carried out on the notes of 125 patients who had attended a dedicated hospital colorectal follow-up clinic between 1988 and 1992. Carcinoembryonic antigen level data were obtained by subsequent examination of the University of Edinburgh Department of Clinical Chemistry (immunoassay section) carcinoembryonic antigen database. RESULTS: A single carcinoembryonic level result of more than 100 ul-1 (normal range less than 60 ul-1) was found to be a highly sensitive (87%), specific (89%), and accurate (88%) indicator of recurrent disease. Raised carcinoembryonic antigen level preceded symptoms in 72% of patients with recurrence of colorectal cancer. CONCLUSION: Sequential laboratory estimation of carcinoembryonic antigen level organized by the general practitioner may represent an accurate method of detecting recurrent colorectal disease. Hospital review could be limited to colonoscopic surveillance and restaging of patients referred with evidence of recurrent disease.

Adult↗
PubMed1995

Critical appraisal and current position of laparoscopic hernia repair.

Laparoscopic hernia repair is still undergoing development and appraisal. This review briefly outlines the history of hernia repair. The six techniques of laparoscopic repair are described and published experience for each of these is discussed. The techniques, which involve simple closure of the neck of the hernial sac with or without closure of the internal ring, appear to have little or no place in adult practice. The plug technique and plug and patch technique represented a transient phase of development and have now been abandoned. Suture techniques have not been widely practised, making current appraisal difficult. Of the mesh techniques the intraperitoneal onlay mesh technique is not recommended. The place of the transabdominal preperitoneal technique and the extraperitoneal technique need to be determined by prospective randomized clinical trials.

Hernia, Inguinal↗
PubMed1994

Superior staging of liver tumors with laparoscopy and laparoscopic ultrasound.

OBJECTIVE: The authors describe the technique of staging laparoscopy with laparoscopic contact ultrasonography in the preoperative assessment of patients with liver tumors, and assess its impact on the selection of patients for hepatic resection with curative intent. SUMMARY BACKGROUND DATA: Laparoscopy may be useful in the selection of patients with a variety of intra-abdominal malignancies for operative intervention. Laparoscopic ultrasonography is a new technique that combines the principles of high resolution intraoperative contact ultrasound with those of the laparoscopic examination, and thus, allows the laparoscopist to perform detailed assessment of the liver. METHODS: This study analyzes a cohort of 50 consecutive patients who were diagnosed as having potentially resectable liver tumors, and in whom staging laparoscopy was successfully undertaken. Laparoscopic ultrasonography was performed in 43 patients, and the impact of the ensuing findings on the decision to proceed to operative assessment of resectability is examined. The resectability rate in those patients assessed laparoscopically and subsequently submitted to laparotomy is compared with a preceding group of patients in whom no laparoscopic assessment was performed. RESULTS: Laparoscopy demonstrated factors precluding curative resection in 23 patients (46%). Laparoscopic ultrasonography identified liver tumors not visible during laparoscopy in 14 patients (33%), and provided staging information in addition to that derived from laparoscopy alone in 18/43 patients (42%). The resectability rate was significantly higher among those patients undergoing laparoscopic staging (93%) compared with those in whom operative assessment was undertaken without laparoscopy (58%). CONCLUSIONS: Staging laparoscopy with laparoscopic ultrasonography optimizes patient selection for liver resection with curative intent.

Adult↗
PubMed1979

Gas-liquid chromatographic determination of monosodium glutamate in soups and soup bases.

A method is given for determining monosodium glutamate (MSG) in soups and soup bases by gas-liquid chromatography (GLC) of the trimethylsilyl ether derivative of glutamic acid. This method compared favorably with existing methods including GLC of the trifluoroacetate (TFA)/butyl ester derivative, and analysis on an amino acid analyzer. In addition, some samples were analyzed by GLC/mass spectrometry. The MSG content of various products ranged from approximately 0.2% in some condensed soups to 13.1% on bouillon cubes. The method, which can detect as little as 0.05%, requires only a 10 min single step derivatization at room temperature and is preferred to the TFA/butyl ester technique.

Chromatography, Gas↗
PubMed1978

Recent studies in Canada on the analysis and occurrence of volatile and non-volatile N-nitroso compounds in foods.

The present paper briefly summarizes the research activities of the Food Research Laboratories, Canadian Health Protection Branch, during the past two years. Data presented indicate that traces of nitrosamines, mainly nitrosodimethylamine and nitrosodiethylamine, can occur in cheese. Several new analytical methods are presented for the determination of non-volatile nitroso compounds, such as nitrosohydroxypyrrolidine, nitrosodiethanolamine, nitrosoproline, nitrosohydroxyproline and nitrosoglyphosphate (a nitrosated herbicide). It is shown that all of the above compounds, even the very polar nitrosoglyphosphate, can be converted to volatile derivatives and then analysed by GLC-MS or by conventional GLC using a specific (such as P-photometric) detector. Traces of nitrosohydroxypyrrolidine have been detected in a few samples of cooked bacon. Contrary to previously reported findings, no significant levels of nitrosoproline were detected in the 6 samples of raw bacon analysed.

Animals↗
PubMed1978

Determination of zearalenone in cornflakes and other corn-based foods by thin layer chromatography, high pressure liquid chromatography, and gas-liquid chromatography/high resolution mass spectrometry.

A simple cleanup procedure based on pH adjustments was used to obtain extracts of corn foods. The method gave good recoveries of zearalenone determined by thin layer chromatography (TLC) and high pressure liquid chromatography (HPLC). As little as 5 ng zearalenone was detected by TLC, using Fast Violet B Salt as the spray reagent; the lower limit of detection in cornflakes was about 20 microgram/kg. With HPLC on Spherisorb silica (5 micrometer) and detection by fluorescence at an excitation maximum of 310 nm as little as 5 microgram zearalenone/kg cornflakes could be determined. While the TLC method was also applicable to corn chips, cornmeal, popcorn, and frozen corn, an interference was observed in HPLC of the latter 3 products. This interference was separated from zearalenone by adding a second HPLC analytical column (Spherisorb ODS). Gas-liquid chromatography coupled with mass spectrometric single ion monitoring at high resolution, although of limited availability, was shown to be the most sensitive and selective method for determining zearalenone in corn foods. The natural occurrence of zearalenone in a sample of cornflakes (13-20 microgram/kg) was demonstrated by all 3 detection procedures.

Chromatography, Gas↗
PubMed1977

Determination of chlorinated pesticides in potable water.

A procedure is described for monitoring organochlorine pesticides in potable water. Material adsorbed from water on to Amberlite XAD-2 macroreticular resin was eluted with n-hexane and the concentrated eluate was analyzed without further treatment. Electron capture (63Ni) gas chromatography utilizing a column of 4% QF-1 and 2% SE-30 on 80-100 mesh HP Chromosorb W at 180 degrees permitted identification of organochlorine pesticides and indicated the presence of phthalates. Confirmatory qualitative and quantitative analyses were done by specific ion-monitoring mass spectrometry. Levels determined in Ottawa drinking water were 17 ppt alpha-BHC, 1.3 ppt lindane, 0.7 ppt aldrin, and less than 0.05 ppt for each of heptachlor, heptachlor epoxide, dieldrin, endrin, chlordane, o,p'-DDT, p,p'-DDD, p,p'-DDT, and p,p'-DDE.

Chromatography, Gas↗
PubMed1976

Nitrosamines in cured meat products.

One hundred samples of specially selected spiced meat products (sausages, salami, bologna, wieners, meat loaf, canned luncheon mean, etc) were analysed for nitrate, nitrite and volatile nitrosamines. None of the samples contained high levels of nitrosamines, but many contained traces, generally in the range from 2-50 mug/kg. Some contained as many as four nitrosamines, namely, NDMA, NDEA, NPip and NPy. In a few cases the samples were reanalysed after two weeks' storage at 4 or -20 degrees C, but no significant change in the nitrosamine levels could be detected. The identity of the nitrosamines was confirmed by GLC-high-resolution-MS.

Animals↗