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Biomedical subjects

J T Roberts

Publications and source records attributed to J T Roberts.

At least 73 records · Page 4Linked to original sources

Results of a randomized, double-blind comparative study of ondansetron and metoclopramide in the prevention of nausea and vomiting following high-dose upper abdominal irradiation.

Ondansetron is a 5-hydroxytryptamine 3-receptor antagonist which has shown activity in the prevention of cytotoxic-induced emesis. Preliminary non-randomized studies also indicated efficacy in preventing sickness following radiotherapy. The present study was therefore undertaken to compare the efficacy and safety of ondansetron (8 mg tds orally) and metoclopramide (10 mg tds orally) in preventing sickness after single-exposure radiotherapy treatments of 8-10 Gy to the upper abdomen. Of 82 evaluable patients 38 received ondansetron and 44 metoclopramide. On the first day after irradiation vomiting or retching was prevented in all but one of the patients on ondansetron whereas metoclopramide achieved complete control of these symptoms in only 46% of subjects (P less than 0.001). Similarly nausea was significantly better controlled by ondansetron in the first 24 hours after treatment (P = 0.001). Complete or major control of vomiting or retching was maintained for 92%-100% of patients on ondansetron during the five days of the study period. In the metoclopramide group the proportion of patients with equivalent control improved from 70% on day 1 to 95 on day 5. Both drugs were well-tolerated.

Abdomen↗

Treatment of carcinoma of the breast with high dose oral medroxyprogesterone acetate: does increased bioavailability improve the therapeutic ratio?

Medroxyprogesterone acetate (MPA) is regarded as a valuable hormonal therapy for metastatic breast cancer. The drug is manufactured by more than one pharmaceutical company, and one particular brand of oral MPA (Provera Tablets, Upjohn) has been reformulated to incorporate micronized particles, providing significantly enhanced bioavailability. The response rate and side-effect data from a pilot study, which used the old formulation Provera Tablets 100 mg at a dosage of 800 mg/day in 28 patients with recurrent breast cancer after treatment with tamoxifen, are compared with those from another study in which 59 similar patients received 800 mg/day of new formulation Provera Tablets 200 mg. Neither of these studies, conducted in the United Kingdom, has previously been published. The response rates were similar in both studies, but there were higher incidences of significant weight gain and increased blood pressure in those patients treated with the new formulation. These side effects have been noticed by other workers employing new formulation MPA at a dosage of 800 mg per day, while it has been reported that reducing the dosage to 400 mg perday is accompanied by a lower incidence of side effects, without affecting the response rate. It is concluded that the increased serum levels of MPA, made possible by the micronized product, do not favourably influence the response of metastatic breast cancer to therapy, but may be associated with a higher incidence of side effects. Reducing the dosage of the new formulation MPA to 400 mg/day may allow a more acceptable side-effect profile, without loss of therapeutic efficacy. Such a dose reduction would make this brand of MPA more cost effective.

Administration, Oral↗

Clinical competence in the performance of fiberoptic laryngoscopy and endotracheal intubation: a study of resident instruction.

Anesthesiologists must be competent in the technique of fiberoptic laryngoscopy and intubation in airway management. The goal of this study was to test the hypothesis that an acceptable level of technical expertise in fiberoptic laryngoscopy and intubation may be acquired within 10 intubations while maintaining patient safety. The learning objectives were an intubation time of 2 minutes or less and greater than 90% success on the first intubation attempt. Ninety-one ASA physical status I-II patients with normal laryngeal anatomy had general anesthesia and were intubated orally with an Olympus LF-1 fiberoptic scope; the mean (+/- SD) time for intubation was 1.92 +/- 1.45 minutes. Four residents with no prior experience with fiberoptic laryngoscopy intubated at least 15 patients each. A learning curve was generated using logarithmic analysis of the mean (+/- SD) time for intubation of patients 1 to 15 for all residents combined. The curve showed that the mean (+/- SD) intubation time decreased from 4.00 +/- 2.91 to 1.53 +/- 0.76 minutes within the first 10 intubations. After the tenth intubation, the mean time was 1.53 minutes and the percent success on the first attempt at intubation was greater than 95%. There were no clinically important changes in O2 saturation, mean arterial pressure (MAP), or heart rate (HR) as a consequence of fiberoptic intubation. The results suggest that an acceptable level of technical expertise in fiberoptic intubation can be obtained (as defined by the learning objectives) by the tenth intubation, and patient safety is maintained.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Desmoplastic malignant melanoma. A clinicopathologic study of 14 cases.

Clinical and pathologic details in 14 cases of desmoplastic malignant melanoma were reviewed. The study group included ten men and four women with a median age of 58 years. Anatomic locations such as the head and neck area (four cases), limbs (five cases), and trunk (five cases) were involved with equal frequency. Follow-up information (median period, 4.6 years) was available for 12 patients, of whom four are alive and disease free, six have had local tumor recurrence, and two have died of their disease. Histologically, these lesions consisted of a malignant fibroblastic skin tumor intimately associated with a superficial melanoma (ten cases) or melanocytic dysplasia (four cases) that often extended deeply to the subcutaneous fat. Helpful diagnostic features included the presence of neurotropism, a lymphocytic infiltrate, and unusual patterns of triangular and periadnexal lamellar fibroplasia. Of the immunohistochemical markers employed, antisera to S100 protein and vimentin yielded the most consistent positive results. Immunostaining with NK1/C-3 (antimelanoma monoclonal antibody) was not helpful. Ultrastructural evidence of fibroblastic and schwannian differentiation was seen. We conclude that the altered morphologic melanomas is associated with a relatively favorable prognosis and believe that careful attention to light microscopic detail with immunohistochemical and electron microscopic assistance will elucidate the diagnosis in most cases.

Adolescent↗

Immunohistochemical detection of antigen in human primary and metastatic melanomas by the monoclonal antibody 140.240 and its possible prognostic significance.

An indirect immunofluorescence technique was used to study the tissue distribution of the epitope recognized by the monoclonal antibody 140.240 which identifies a p97-like melanoma-associated oncofetal antigen. Cryostat sections of various normal and neoplastic human tissues were examined. The presence of antigenic activity was demonstrated in 20 of 39 (51%) primary skin melanomas, in 21 of 52 (40%) metastatic melanomas, and in 20 of 44 (45%) nevi. The reactive nevi were restricted to intradermal, junctional, compound and spindle cell types. Of the 110 samples of 12 major tumor types other than melanoma tested, only 1 of 6 epidermoid tumors, 1 of 4 benign breast tumors and 1 of 5 prostatic tumors gave weak staining. This antibody also reacted with sweat glands and fetal small intestine tissue, but not with other adult or fetal normal tissues. Intrapatient as well as interpatient heterogeneity in the epitope expression was present in primary as well as metastatic tumor lesions surgically removed from patients with melanoma. Evaluation of the immunohistologic data and the clinical outcome of patients with melanoma reveals that the expression of the epitope recognized by this antibody is associated with a more favorable prognosis.

Antibodies, Monoclonal↗

The value of nuclear contour index in the diagnosis of mycosis fungoides. An assessment of current ultrastructural morphometric diagnostic criteria.

Skin biopsy specimens from 43 patients with established mycosis fungoides (MF) and 28 with non-MF lymphoid skin infiltrations were studied by transmission electron microscopy. The nuclear contour index (NCI) of infiltrating lymphoid cells was obtained by means of a Zeiss Videoplan computer and measuring tablet. Classification of the material into MF and non-MF groups was done according to the diagnostic criteria used by McNutt et al. (1980, 1981) and Meijer et al. (1980); this study evaluates the usefulness of these previously published criteria based on quantitative electron microscopy. Statistical analysis confirmed that the mean NCI (MNCI) of the lymphoid cells of patients with MF is significantly greater than that in patients with other lymphoid infiltrates (P less than 0.001). However, all published diagnostic criteria (McNutt et al., 1980, 1981, and Meijer et al., 1980) tested in the authors' larger patient population yielded lower sensitivity than has been reported. The diagnostic criteria based on values of MNCI, percentage of lymphoid cells with NCI greater than 7, and percentage of lymphoid cells with nuclear profile area of greater than 30 microns2 reported by McNutt et al. (1981) appear to be better than others, and provide the highest sensitivity rate, which is in the range of 44% to 47%. There were no false-positive findings. It was concluded that the use of ultrastructural morphometry according to the techniques and diagnostic criteria of McNutt et al. (1981) is useful in the diagnosis of MF.

Adolescent↗

A phase II study of CCNU with benznidazole for metastatic malignant melanoma.

The response of 18 patients with metastatic malignant melanoma to the combination of CCNU (130 mg/m2) preceded 3-4 hr earlier by 20 mg/kg of the 2-nitroimidazole benznidazole has been studied. There were four partial and no complete responses in 16 patients evaluable after 1-6 courses. The median response duration was 14 wk (range 5-33) and for static disease 24 wk (range 10-54). Evidence for chemosensitization is equivocal.

Drug Evaluation↗