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Biomedical subjects

S Wilson

Publications and source records attributed to S Wilson.

At least 361 records · Page 20Linked to original sources
PubMed1993

Small encapsulated hepatocellular carcinoma of the liver. Provisional analysis of pathogenetic mechanisms.

BACKGROUND: Small hepatocellular carcinomas frequently were found incidentally during routine pathologic examinations of adult livers removed at liver transplant. METHODS: Sixty-nine carcinomas of all sizes were found in 25 patients; 39 of the tumors were smaller than 1 cm in diameter, and 18 of the carcinomas in five patients were not clinically suspected. These small incidental carcinomas lend themselves to analysis of the morphologic basis of human hepatocellular carcinogenesis. RESULTS: All of these tumors arose in cirrhotic livers. Most of the small carcinomas were multilobulated and subdivided by pre-existing fibrous septa. The surrounding capsule usually was not a true capsule. They were all well differentiated, most formed bile, Mallory bodies, or showed alpha-1-antitrypsin (A1AT) positivity. Transition from cirrhotic nodular parenchyma to areas of hyperplasia or atypical hyperplasia to well-differentiated carcinoma were common. Large cell dysplasia also was common. CONCLUSIONS: These morphologic transitions closely parallel changes seen in experimental chemical carcinogenesis. They also strongly suggest a multicentric origin of the tumors. In addition, in every instance, the lesions were multiple in the liver and involved both lobes. This latter finding has possible implications for recurrence after local surgical excision of small hepatocellular carcinomas.

Adult↗
PubMed1993

Immunolocalization of cytokines in the nasal mucosa of normal and perennial rhinitic subjects. The mast cell as a source of IL-4, IL-5, and IL-6 in human allergic mucosal inflammation.

Allergic mucosal inflammation is characterized by the presence of cell infiltration, predominantly with IgE-sensitized mast cells and activated eosinophils, and appears to be regulated by the local production and release of several cytokines, particularly IL-4 and IL-5. Although attention has focused on the Th2 subpopulation of CD4+ T lymphocytes as an important source of these cytokines, human mast cells have been shown to both store and secrete IL-4 and TNF-alpha. To investigate the expression of cytokines relevant to allergic inflammation and to identify their cellular localization within the nasal mucosa, we have undertaken specific immunohistochemical staining of thin sections of inferior turbinate biopsies from patients with perennial allergic rhinitis and, for comparison, from nonatopic healthy volunteers. The cytokines investigated were IL-4, IL-5, IL-6, and IL-8. In both the normal and rhinitic biopsies numerous cells immunoreactive for IL-4, IL-5, and IL-6 were seen. Staining of adjacent 2-microns sections for CD3, mast cell tryptase, and eosinophil cationic protein revealed that 90% of the IL-4 immunoreactive cells were mast cells, with biopsies from rhinitic subjects containing significantly more IL-4+ cells than biopsies from normal controls (p = 0.02), especially when assessed with the anti-IL-4 mAb 3H4. Mast cells also accounted for > 90% of IL-6 and > 50% of IL-5 immunoreactive cells. IL-5 immunoreactivity was also localized to eosinophils, whereas IL-8 localized predominantly to the nasal epithelium in both groups. No cytokines were found in association with T lymphocytes. These findings indicate that the mast cell is an important source of preformed cytokines and as such may contribute to the chronicity of the mucosal inflammation that characterizes allergic rhinitis.

Adult↗
PubMed1993

Structural characterization and biological effects of photocyclized products of tamoxifen irradiation.

Tamoxifen (TAM) is an antiestrogen useful in the treatment and control of breast cancer. Exposure of solutions of TAM to UV irradiation produces mixtures of fluorescent derivatives that are useful in the analytical detection and quantitative determination of TAM. The two major products of such irradiations were isolated and assigned unambiguous structures based on analysis of UV and 1H NMR spectral data. Results were in accordance with earlier studies that indicated these products to be substituted phenanthrenes produced by dehydrogenation of cyclized intermediates subsequent to partial isomerization of TAM. Each of the phenanthrenes suppressed MCF-7 human breast cancer cell growth in a dose-dependent manner, but neither compound was as potent as TAM in this regard. Also, unlike treatment with TAM, cell growth could not be restored in the presence of either of the phenanthrenes by simultaneous exposure to estradiol.

Breast Neoplasms↗
PubMed1993

Deletion of residues K296-G302 from the slowly-cleared tissue-type plasminogen activator t-PA del (G) leads to partial loss of plasminogen activating activity.

Plasmids encoding tissue-type plasminogen activators lacking residues K296-G302 were constructed and were expressed in a Hela cell transient expression system. Conditioned media from the cultures were tested in a number of systems designed to detect function or antigen. Functional assays comprised the chromogenic substrate S2288 and three plasminogen activation assays. All t-PA variants were active in all assays but to varying degrees. The results are consistent with the conclusion that deletion of residues K296-G302 from the slowly-cleared t-PA mutant t-PA del(G) adversely affects the plasminogen activating ability of the molecule without altering the integrity of the active site. This is in contrast to the situation in native t-PA where the same mutation has little overall effect on activity.

Binding Sites↗
PubMed1993

Comparison of bone volume and strength as measures of skeletal integrity in caged laying hens with access to perches.

Fractures in spent laying hens are now recognised as a major welfare problem; the objective of this work was to determine whether provision of perches for caged layers would increase bone strength, bone volume or both. Sixteen ISA Brown hens were housed from 18 to 72 weeks old in cages with perches and 16 in similar cages without perches. At the end of lay the birds' tibiotarsi were examined for strength by a three-point loading test and their tarsometatarsi for bone volume by histomorphometry. There was no significant effect of perches on tibiotarsal breaking strength. Hens from both groups showed evidence of osteoporosis, but it was more severe in the birds from conventional cages: tarsometatarsal trabecular bone volume was greater in the hens which had access to perches. A positive correlation was found between trabecular bone volume and the degree of day-time perch usage by individual hens. Provision of perches can have a slight but significant beneficial effect, at least for the leg bones, in increasing the bone volume of caged laying hens.

Animals↗
PubMed1993

Effects of perches on trabecular bone volume in laying hens.

Trabecular bone remodelling is known to be affected by loading or exercise, and thus exercise may effect the trabecular bone loss associated with osteopenia in laying hens. Sixteen ISA Brown hens were housed from 18 to 72 weeks old in cages with perches and 16 in similar cages without perches to examine the effects of the exercise afforded by perch provision on trabecular bone volume. At 72 weeks, mean trabecular bone volume in the proximal tarsometatarsus of birds with access to perches was significantly greater than in control birds, while medullary bone volume was not significantly different in the two groups. However, all the birds were considered osteoporotic, though to varying degrees, and the beneficial effects of perches were relatively minor. It was concluded that while trabecular bone loss may be reduced by perch provision, other factors are probably more influential in the development of the osteoporosis typical of laying hens.

Animals↗
PubMed1993

Clinical experience with Mentor Alpha I inflatable penile prosthesis. Report on 333 cases.

Penile prostheses are a well-established form of therapy for erectile dysfunction. We report our experience with 333 cases using the Mentor Alpha I inflatable penile prosthesis. With a follow-up period of 15.4 months, there were 25 (7.5%) complications with 15 (4.5%) major complications that required reoperation. We also review the advantages and the procedures for implanting the penile prosthesis on an outpatient basis or a one-day hospital stay.

Adult↗
PubMed1993

The diameters of guinea pig auditory nerve fibres: distribution and correlation with spontaneous rate.

In the mammalian auditory nerve physiological recordings revealed that the spontaneous discharge rate of single auditory fibres correlates with the diversity of input-output functions which may be important for intensity discrimination (e.g., Sachs and Abbas, 1974, Liberman, 1978; Winter et al., 1990). In this study we determined if the spontaneous discharge rate of auditory nerve fibres in the guinea pig is correlated with an anatomical feature, namely the diameter of the respective fibres. The diameter of myelinated (Type I) guinea pig auditory nerve fibres was measured after staining with different techniques. Measurements were made on semithin sections using a video image analysis system. The diameters of fibres stained with toluidine blue from the portion of the auditory nerve containing fibres from the basal turn of the cochlea were found to have a normal distribution. Fibres were also labelled with horseradish peroxidase by bulk injection into the spiral ganglion. It was found that the presence of horseradish peroxidase within the fibres reduced the measured diameter in comparison to adjacent unlabelled fibres. A number of fibres were physiologically characterized with respect to spontaneous discharge rate and subsequently intracellularly labelled with horseradish peroxidase. Fibre diameter of a selected sample of intracellularly fibres was measured over a distance of 800 microns within the internal auditory meatus. At the positions nearest to the spiral ganglion fibres possessing low spontaneous rates were found to have smaller diameters than high spontaneous rate fibres. No difference in fibre diameter was found for the positions near the cochlear nucleus.

Animals↗
PubMed1993

A review of parotid pleomorphic adenomas in the West Midlands region 1977-1986.

The aim of this study was to review the management of parotid pleomorphic adenomas in the West Midlands Regional Health Authority. The study population consisted of all cases of pleomorphic adenomas arising in the parotid and registered with the West Midlands Regional Cancer Registry between 1 January 1977 and 31 December 1986. Variables included in the analysis were: age, sex, year of diagnosis, treatment centre, consultant specialty, operative procedure, completeness of tumour resection and treatment modality. The main findings were that the choice of operative procedure and the use of adjuvant radiotherapy varied significantly between treatment centres and could not be explained by intraregional variation in the distribution of patient and disease related factors; less than one-third of patients in this series were managed according to accepted treatment protocols.

Adenoma, Pleomorphic↗
PubMed1993

Incidence and survival of malignant parotid tumours in the West Midlands region 1977-1986.

The aim of this study was to describe the incidence and survival of patients with malignant parotid tumours resident in the West Midlands Regional Health Authority. The study population consisted of all patients with malignant tumours arising in the parotid gland and registered with the West Midlands Regional Cancer Registry between 1 January 1977 and 31 December 1986. Variables included in the analysis were: age, sex, date of diagnosis, side of origin, tumour histology, vital status and date of death. No temporal change in the incidence of parotid tumours was observed. More tumours originated within the left parotid gland (chi 2(1) = 4.0, P < 0.05). The 5-year actuarial survival for all tumours was 55.7%. When a Cox's proportional hazards regression model was fitted to the data, age at diagnosis (60-74 years) and histological type were found to be the critical determinants of outcome.

Adolescent↗
PubMed1993

Theory to practice: developing a Rogerian-based assessment tool.

Nursing models are invaluable in the direction they provide for nursing practice, education and research. The growth and development of the nursing profession is enhanced when its practice is guided by nursing theory. Rogers' Science of Unitary Human Beings is appealing to nursing because of its open-systems perspective and focus on holistic and individualistic care. Rogers' model is utilized to develop a nursing assessment tool that may be used in a variety of situations. The Rogerian-based assessment tool is used to gather data from a postpartum mother experiencing the challenges of her first newborn. Problems incurred while developing and utilizing the tool are discussed. Rogers' model is shown to be practical and effective in this case study.

Adult↗
PubMed1993

Is osteoarthritis in women affected by hormonal changes or smoking?

The influence of sex hormone related events and smoking on the development of OA in women was investigated in a case-controlled postal survey. One hundred and twenty-nine patients with nodal generalized osteoarthritis (NGOA) and 145 with non-nodal pauciarticular large joint osteoarthritis (LJOA) were identified from the database of a Nottingham OA clinic. For each patient, three age-matched controls were randomly selected from the same general practice. Sixty-three per cent of questionnaires (690/1096) were returned: NGOA, 95; NGOA controls, 226; LJOA, 113; LJOA controls, 256. There were no differences in age at menarche or menopause, rates of hysterectomy, oral contraceptive use, or hormone replacement use between cases and controls. Fewer OA patients had ever smoked [(Odds Ratio (OR) 0.65, 95% Confidence Interval (CI) 0.45-0.95)] and subset analysis demonstrated that this negative association occurred only in the LJOA group (OR 0.43, CI 0.25-0.72), particularly in those with knee OA (OR 0.29, CI 0.14-0.62). A previous successful pregnancy was negatively associated with NGOA (OR 0.47, CI 0.24-0.95). This study demonstrates no association between oestrogen-related hormonal events and OA, but a negative association between smoking and LJOA. Such data supports the concept that OA is a heterogeneous disease and underlines the need to differentiate OA subsets.

Age Factors↗
PubMed1993

Rheumatic manifestations of neoplasia.

Recent literature on the rheumatic manifestations of neoplasia has again focused on the increased association of Sjögren's syndrome and rheumatoid arthritis with lymphoproliferative malignancies and leukemias. A series of 13 patients with monocytoid B-cell lymphoma, a recently described variant of low-grade B-cell lymphoma, and Sjögren's syndrome was reported. The skeletal manifestations of leukemias are extensively reviewed emphasizing that osteoarticular manifestations may predate the hematologic disease. A case of monoarthritis of the knee as a manifestation of chronic leukemia is presented in which synovial biopsy revealed a leukemic infiltrate. Recent studies looking at the association of polymyositis and dermatomyositis with malignancy challenge this link. Two cases of malignancy presenting with polyarthritis are reviewed, and in both cases the polyarthritis resolved with removal of the tumor. A case report and a series of synovial sarcomas are also reviewed. Hodgkin's disease can initially present with skeletal involvement; six cases are reviewed.

Humans↗
PubMed1993

Serve Our Seniors, Inc.--a demonstration program for proposed California menu guidelines for senior nutrition. California Department of Aging.

Revised menu guidelines, written by the California Department of Aging (CDA) for senior nutrition programs, were tested by Serve Our Seniors, Inc. in a demonstration program from January '91 through June '92. Results showed improved nutrient value of the meals through increasing fiber, and decreasing sugar and fat. New menus were accepted by senior participants with little resistance. Project food costs increased 4%. Guidelines were used in a variety of project kitchens, with minimal staff training. Limited storage was a problem. Vendors were encouraged to identify appropriate foods and control costs.

Aged↗
PubMed1993

Flumazenil in alcohol withdrawal.

This is a preliminary study to explore the theory that there may be abnormalities of the benzodiazepine receptor, or a possible endogenous inverse agonist ligand in alcohol withdrawal. The benzodiazepine antagonist flumazenil was administered to 8 alcoholics in early withdrawal in a double blind placebo controlled design. Self ratings of mood and physical symptoms, and observer ratings of withdrawal symptoms revealed differences in the effects of flumazenil and placebo. Flumazenil had an immediate slight anxiogenic action which was short-lived. It then appeared to ameliorate withdrawal symptoms, quite markedly in 2 patients.

Adult↗