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W Ryd

Publications and source records attributed to W Ryd.

At least 37 records · Page 2Linked to original sources
PubMed1994

Leukotriene B4 and C4 generation by small intestinal mucosa in children with coeliac disease.

The capacity of the small intestinal mucosa to generate leukotriene B4 (LTB4) and C4 (LTC4) in children with coeliac disease (CD) was investigated by measuring the production of LTB4 and LTC4 in intestinal biopsy specimens after stimulation with 10 microM calcium ionophore A23187. In addition, we examined the relationship between the production of LTB4 and LTC4 in the small intestinal mucosa and symptoms of diarrhoea. LTB4 and LTC4 production was significantly higher in biopsies from patients with active CD than from controls (p < 0.05 and p < 0.01, respectively). There was no significant difference in LTB4 and LTC4 production between patients with inactive CD and controls. In both patients with active CD and controls, no difference in LTB4 and LTC4 production was observed between the patients with and without diarrhoea. These findings suggest that enhanced generation of LTB4 and LTC4 in the small intestinal mucosa may contribute to the pathophysiology of CD but would not be related to the development of diarrhoea.

Calcimycin↗
PubMed1993

Endovaginal scanning of the endometrium compared to cytology and histology in women with postmenopausal bleeding.

Endovaginal scanning (EVS) of the endometrium has recently been proposed as a method for the investigation of the endometrial mucosa. In this study, the specificity and sensitivity of EVS have been compared with endometrial cytology and D&C to discriminate between a normal and pathological endometrium. The study included 105 women who underwent preoperative endovaginal ultrasound investigation, endometrial cytology, and D&C because of postmenopausal bleeding. A specificity of 81% and a sensitivity of 97% in diagnosing morphological alterations by means of endovaginal ultrasound was found. The corresponding figures for cytological evaluation were 81 and 58%, respectively. We conclude that endovaginal ultrasound is a valuable diagnostic instrument for detecting pathological conditions in the uterine mucosa and as sensitive as endometrial cytology or D&C.

Aged↗
PubMed1993

The prevalence of "high-risk" HPV types in penile condyloma-like lesions: correlation between HPV type and morphology.

OBJECTIVE: To evaluate the prevalence of "high-risk" human papilloma virus (HPV) types in penile condyloma-like lesions and to correlate HPV types with clinical and histological features. DESIGN: The study included 94 male patients with signs of penile HPV infection. From acuminate, papular and macular lesions, specimens were collected for HPV DNA hybridisation, using the dot blot and Southern blot techniques. Biopsy specimens from 51 cases were examined by light microscopy for signs of koilocytosis and dysplasia. SETTING: The STD outpatient clinic of the Department of Dermatovenereology of Sahlgrenska Hospital, Göteborg, Sweden. RESULTS: In 79 (90%) of 88 patients HPV DNA was detected by dot blot. Of 51 cases examined by histology 88% disclosed an evident koilocytosis. "High-risk" HPV types (16, 18, 31, 33, 35) were demonstrated in 8% of acuminate, 24% of papular and 56% of macular lesions. In 29% of 51 lesions examined histologically moderate to severe dysplasia was observed. There was a significant correlation between "high-risk" HPV types and dysplasia. CONCLUSION: "High-risk" HPV types are prevalent in papular and especially macular penile condyloma-like lesions. The histological finding of koilocytosis concomitant with dysplasia strongly indicates infection with a "high-risk" HPV type. Although the risk of penile cancer is low, it is from an epidemiological point of view important to diagnose these lesions. Until simple tests for HPV typing are available, biopsy for light microscopy (histology) should be obtained liberally from papular and macular condyloma-like lesions. In atypical cases of balanoposthitis HPV aetiology should also be considered.

Adolescent↗
PubMed1993

Quantitative importance of asbestos as a cause of lung cancer in a Swedish industrial city: a case-referent study.

We wanted to assess the quantitative importance of asbestos as a cause of lung cancer. In a case-referent study, the exposure to asbestos, tobacco smoke and some other occupational exposures were compared between 147 cases of lung cancer (100 men, 47 women), 111 hospital referents, and 109 population referents, all below the age of 75 yrs and living in an industrial city. The attributable risk of lung cancer due to asbestos exposure was 16% in men (95% confidence interval 1-31%). No woman had occupational exposure to asbestos. We conclude that in the mid 1980's tobacco smoking was the major attributable risk, being 95% for men and 78% for women, but that in men asbestos was an appreciable contributing factor in the general population of a Swedish industrial city.

Adult↗
PubMed1991

Arabinogalactan blockade of experimental metastases to liver by murine hepatoma.

Blocking of organ-specific experimental metastasis was investigated in a syngeneic tumor-host system using a new tumor which primarily colonizes the liver upon intravenous injection. The study included systemic treatment with D-galactose and arabinogalactan as well as cell pretreatment with arabinogalactan and two other glycoconjugates. Treatment with arabinogalactan reduced the amount of liver metastases and prolonged the survival times of the animals in both studies. Host treatment was more effective than tumor cell pretreatment. This could be an effect of arabinogalactan blockade of potential liver receptors by covering of galactose-specific binding sites.

Animals↗
PubMed1990

Chlorpromazine-induced hypothermia in tumour-bearing mice, acute cytotoxic drug lethality and long-term survival.

The acute lethality of various cytotoxic drugs (doxorubicin, vinblastine and nitrogen mustard) and long-term survival in a syngenic mouse-tumour system were studied at normal body temperature and at 28 degrees C induced by chlorpromazine. Chlorpromazine-induced hypothermia itself neither caused acute toxicity nor influenced long-term survival. Doxorubicin (15 mg/kg) and nitrogen mustard (6 mg/kg) lethality was reduced at decreased temperature. The median survival time increased significantly from 35 days in normothermic to 52 days in hypothermic doxorubicin-treated mice. With nitrogen mustard, no increase in long-term survival was seen in the hypothermic group. The acute lethality of vinblastine was enhanced by hypothermia and the long-term tumour survival was unaffected. Hypothermia or possibly chlorpromazine considerably modulates drug toxicity and possibly anti-tumoural activity.

Animals↗
PubMed1990

Lectin binding in murine tumour lines with different malignant characteristics. Effect of enzyme (pronase, neuraminidase) treatment on lectin labelling.

We used 5 syngeneic murine tumour systems for studying quantitative lectin surface binding of intact viable tumour cells. We also investigated, for 3 of the tumours, whether the lectin binding sites were susceptible to proteolytic enzyme (pronase) or neuraminidase treatment. There were significant differences between two of the tumour lines in the binding of wheat germ agglutinin (WGA), concanavalin A (ConA). peanut agglutinin (PNA), soybean agglutinin (SBA) and Ulex europeus agglutinin (UEA). There were also variations in lectin binding between the other tumor lines, but these differences were not statistically significant. Lectin binding showed no evident relationship to the malignancy or the metastasis-forming capacity of the respective tumour cell line. Proteolytic treatment, which drastically affects intravenously induced experimental metastasis formation by one of the tumours, caused a decreased binding of SBA, ConA and WGA. Neuraminidase treatment increased both PNA and SBA binding in three different cell lines, presumably by removing sialic acid masking D-galactose and N-acetyl-D-galactose-amine groups.

Animals↗
PubMed1988

Characteristics of two malignant lymphomas in C57B1/6J mice. Cytogenetic changes and the distribution of i.v. transfused tumor cells with and without enzyme (pronase, neuraminidase) treatment.

Two T-cell lymphomas induced by a combination of antigen stimulation and immunosuppression in inbred C57Bl/6J mice, BWL1 and BWL2 (Ryd et al. 1985), were further characterized. Cytogenetically they have the same trisomy 15 abnormality as chemically, virally and radiation induced T-cell lymphomas. Analyses of early and late tumour generations indicate that both tumours are chromosomally stable. After i.v. transplantation, the two tumors grew in a similar manner and preferentially in spleen and liver. Proteolytic treatment of the tumor cells changed the distribution of both lymphomas from the lungs to other organs. Neuraminidase treatment had no such effect on BWL2, but a similar but weaker effect than pronase on BWL1. Our findings support the notion that the distribution of lymphomas are, at least in part, governed by cell-surface characteristics.

Animals↗
PubMed1986

Ancient neurilemmoma: a pitfall in the cytologic diagnosis of soft-tissue tumors.

A case of ancient neurilemmoma (Schwannoma) is presented that, owing to a severe cell pleomorphism, was falsely interpreted as a malignant spindle-cell sarcoma by fine-needle aspiration cytology. Cytological features of the tumor are given together with its histopathology and electron microscopy findings. The usefulness of electron microscopy on material obtained by fine-needle aspiration biopsies in the diagnosis of soft-tissue tumors is discussed.

Adult↗
PubMed1986

Effects of zinc on tumor transplantability.

The effects of zinc treatment on the transplantability of tumor cells were investigated in two syngeneic murine tumor systems. A 15-min incubation of tumor cells in 0.1 mM zinc caused a dramatic decrease in intravenous transplantability for melanoma B16 cells, while MCG 101-AA cells were unaffected. The subcutaneous transplantability remained unchanged in both cases. In order to elucidate the mechanism responsible for the effect on B16 cells, a number of factors of possible importance for the intravenous transplantability were investigated. Zinc treatment reduced the activity of extracellular neutral protease, and increased the cell rigidity and fragility in a similar way in both cell lines. However, zinc effects on cell adhesion and cell proliferation were different in the two cell lines. It is possible that zinc reduces the intravenous transplantability of melanoma B16 cells by impairment of cell adhesion.

Aminopeptidases↗
PubMed1986

Characterization of two murine tumor sublines selected purely in vivo for specific metastatic patterns.

We have attempted to clone an ascites tumor, MCB 21-AA, which was originally a fibrosarcoma, by transplantation of spontaneous metastases from the lungs or a lymph node to a subcutaneous site, and by repetition of this procedure ten times. We isolated two tumor sublines, LU (from lung) and LN (from lymph node), which differ from the original tumor in several cell characteristics. When tested for the formation of experimental metastasis, these sublines disseminate in the same manner as the original tumor. We interpret this finding as an argument against the widely held view that metastasis is a highly selective cloning process.

Animals↗
PubMed1985

Dissemination pattern of two immunologically induced transplanted malignant lymphomas in C57 B1/6J mice.

The need for syngenic tumors to elucidate factors in lymphoma dissemination prompted us to induce new lymphomas in a series of inbred C57B1/6J mice. The method of induction, immunosuppression and simultaneous immunostimulation, had a high mortality rate, but gave us 2 transplantable lymphomas. These tumors are described and compared in the present paper, with emphasis on their dissemination patterns. Both tumors disseminated rapidly from tail transplants to lymphoid organs, lungs and liver. They were characteristically dissimilar, however, in their s.c., i.p. and i.v. transplantabilities.

Animals↗
PubMed1985

Altered experimental metastasis pattern by proteolytic cell treatment.

We have studied some cellular characteristics and the transplantability of a newly induced squamous cell carcinoma, Sq1-SC, in comparison with the ascites-transformed subline of the same tumor, Sq1-AA. We could demonstrate that the AA tumor differed from the SC tumor in the pattern of intravenously induced 'experimental metastases'. The SC tumor preferentially gave rise to extrapulmonary tumor colonies ('metastases'), while the AA tumor exclusively gave rise to lung colonies. Comparison with the ascites tumor growing in solid form subcutaneously (AS tumor) shows that the enzymatic treatment, which is necessary to bring solid tumors into viable and dissociated suspensions, can have a decisive influence on tumor cell lodgement in vessels and metastasis.

Animals↗
PubMed1984

Effects of fine-needle aspiration and other biopsy procedures on tumor dissemination in mice.

Using five syngeneic tumor-host systems in mice, we studied the influence of fine-needle aspiration biopsy, incisional biopsy, and excisional biopsy on tumor death rates. Guided by results from pilot studies a very strict test protocol was developed which made possible a comparison between the tumor systems in spite of their differences in tumor growth rates and dissemination patterns. The compiled results from the experiments did not reveal any differences in tumor death rates, neither between the test groups and their controls, nor between the three biopsy methods: fine-needle aspiration biopsy, incisional biopsy, and excisional biopsy. Additional experiments confirmed, however, earlier observations that tumor cell seeding and tumor outgrowth by way of the aspiration needle track may occur under extreme test conditions.

Animals↗
PubMed1984

The tumor-cell-releasing machine.

We describe the construction of a machine for the injection of 10- to 100-microliter volumes of viable cells in suspension. The cells are maintained in a tissue culture environment and can be injected according to a preprogrammed schedule. Preliminary results show that the tumor incidence and metastasis pattern of TA3Ha cells injected intravenously into mice are the same if the cells are injected in a single dose, or administered in 20 fractions during 3 h.

Animals↗