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S Olsen

Publications and source records attributed to S Olsen.

At least 91 records · Page 5Linked to original sources
PubMed1990

Histological evaluation of prostatic cancer. (III): Reproducibility of assessment of tumour volume and its possible significance for prognosis.

The aim of this study was to evaluate the INTER- and INTRA-observer reproducibility of prostatic cancer volume defined as the percentage of chips with carcinoma in transurethrally resected tissue. All histological slides from 80 consecutive cases of prostatic cancer were blindly evaluated on two independent occasions by each of four pathologists. The correlation was expressed by Spearman's rank correlation coefficient (R). Both the overall INTER- and mean INTRA-observer correlation of tumour volume were high with R being respectively 0.905 and 0.918. With reference to stage A1 and A2, data were transformed to an ordinal scale with 2 categories (less than = 5%, greater than 5%). The overall INTER- and mean INTRA-observer agreement of this classification were 0.926 and 0.943 respectively--the corresponding kappa coefficients being 0.68 and 0.74. It is concluded that in transurethrally resected tissue a highly reproducible index of the resected prostatic cancer volume can be given by the percentage of chips with tumour. The prognostic significance of this parameter is discussed.

Humans↗
PubMed1990

In vitro antiplaque effects of a triclosan/copolymer mouthrinse.

The influence of a mouthrinse containing 0.03% triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) and 0.25% copolymer (polyvinylmethylether maleic acid copolymer), compared to a matching placebo rinse, on in vitro plaque formation was assessed in two dynamic plaque model systems. In the controlled saliva flow cell system, the triclosan-containing rinses significantly reduced total plaque compared to the placebo rinse, with no significant differences when copolymer was removed from the active rinse formula. In the continuous culture system (chemostat flow cell model), the mean plaque was significantly reduced when compared with placebo. The results of these studies indicate that a triclosan mouthrinse, in the presence or absence of copolymer, is effective in reducing plaque in vitro.

Bacteria↗
PubMed1990

Antiplaque effects of dentifrices containing triclosan/copolymer/NaF system versus triclosan dentifrices without the copolymer.

A dentifrice containing triclosan/PVM/MA, Colgate Gum Protection Formula Toothpaste (GPF), was found to be highly effective against oral bacteria with minimal inhibitory concentration ranging from 0.3 to 5.35 micrograms/ml. A variety of in vitro model systems simulating oral environment were used to compare dentifrices containing triclosan/PVM/MA versus the dentifrices containing triclosan without PVM/MA, such as Crest Gum Health Toothpaste (CGH) and Neo-Mentadent P Toothpaste (N-MP). The uptake of triclosan on saliva-coated hydroxyapatite (HA) disks and buccal epithelial cells was significantly higher from the GPF versus the other dentifrices. Uptake on HA disks was 132 micrograms/disk versus 11 micrograms/disk from CGH; on buccal epithelial cells the uptake was 59 micrograms/2 x 10(5) cells with GPF versus 30.0 micrograms with CGH per same number of cells. The retained triclosan on the surfaces provided a sustained and higher antibacterial effect up to 4 hours post-treatment with GPF, but not with N-MP and CGH. In dynamic plaque model systems such as the chemostat or the controlled saliva flow system, GPF was significantly (P = 0.05) more effective than N-MP or CGH in reducing plaque thickness, protein and carbohydrate contents of plaque films. Collectively, the results of these microbiological and biochemical investigations indicate that the GPF has the potential to provide superior clinical efficacy versus the dentifrices without the copolymer.

Dental Plaque↗
PubMed1989

Immunohistochemistry and cytochemistry of experimental rat bladder cancer: binding of the lectins PNA and WGA and of a Le(Y) mouse monoclonal antibody.

Two lectins, peanut agglutinin (PNA) and wheat germ agglutinin (WGA), and a mouse monoclonal antibody against blood group Le(Y) were used to study the distribution of carbohydrate antigens in an experimental rat bladder cancer model. Neoplasia was induced in 28 rats by intravesical installation of N-nitroso-N-methyl-urea (NMU). Fifteen rats were installed with the NMU solvent and served as controls. Urothelial samples were taken from all animals, the atypia were graded and detailed data on the location of the lectin-binding structures and the binding of the monoclonal antibody were obtained by immunohistochemical methods. Urine samples were collected at different times during tumor development and data on the cytological location of the lectin-binding structures and the binding of the monoclonal antibody were obtained by immunocytochemical methods. Examination of the histological distribution of lectin binding structures and Le(Y) antigen showed a characteristic change in carbohydrate antigen expression associated with the development of urothelial atypia. In normal urothelium carbohydrate antigens were present in cytoplasm, whereas they became expressed on cell membranes in non-invasive carcinomas. Immunocytochemistry of urine specimens revealed a lack of correlation between the antigen expression found in exfoliated cells and that found in tissue. Morphologically normal cells from NMU-treated animals were found to express a carcinoma associated antigen pattern.

Animals↗
PubMed1989

Primary acute renal failure ("acute tubular necrosis") in the transplanted kidney: morphology and pathogenesis.

"Acute tubular necrosis" (ATN) in the transplanted kidney, when properly differentiated from other causes of acute renal failure, appears to be a relatively benign condition. It has been widely assumed to be pathologically identical to ATN in the native kidney, but its histopathologic features have not been studied in detail. Because immunosuppressive therapy with cyclosporine adds an additional layer of complexity to the morphologic changes observed, in the present study we have confined our observations to patients immunosuppressed with steroids and azathioprine. Thirteen renal allograft biopsies from patients with ATN and 5 biopsies from patients with normal allograft function were compared with the previously obtained series of 57 native kidney ATN biopsies and 20 control biopsies. Both qualitative and quantitative differences between transplant and native kidney ATN were found. Compared with native kidney ATN, transplant ATN showed significantly less thinning and absence of proximal tubular brush border and less variation in size and shape of cells in individual tubular cross-sections. There were also significantly fewer casts and less dilatation of Bowman's space and a significantly greater number of polarizable crystals presumed to be oxalate in transplant ATN. In native kidney ATN the tubular injury sites were mostly characterized by desquamation of individual epithelial cells leaving areas of bare basement membrane (the "non-replacement" phenomenon). In transplant ATN, sites of tubular injury, although rare and affecting only short tubular segments, were characterized by the actual presence of identifiable necrotic tubular cells, a finding seldom seen in native kidney ATN. There also was a greater interstitial infiltrate of mononuclear inflammatory cells in transplant ATN compared to native kidney ATN. Electron microscopic studies of 9 transplant ATN biopsies showed a mild reduction in proximal tubular brush border compared with controls but this alteration was significantly less than that observed in native kidney ATN. There was no significant alteration in proximal or distal basolateral infoldings and this contrasted sharply with the marked reduction in basolateral infoldings of the plasma membrane observed in native kidney ATN. Disintegrated necrotic cells were found by electron microscopy in transplant ATN whereas these were not observed in native kidney ATN. There were significantly more cells with apoptosis (shrinkage necrosis) in transplant ATN than in native kidney ATN. There were significantly more cells with apoptosis (shrinkage necrosis) in transplant ATN than in native kidney ATN. On the other hand, there were significantly greater numbers of "non-replacement" sites in the distal tubules in native kidney ATN compared to transplant ATN.(ABSTRACT TRUNCATED AT 400 WORDS)

Actins↗
PubMed1989

Reproducibility of histomorphologic diagnoses with special reference to the kappa statistic.

Systems for classification and grading used in pathology should ideally be biologically meaningful and at least be reproducible from one pathologist to another. A statistical method to evaluate reproducibility (non-chance agreement) for several observers using nominal or ordinal categories has been developed and refined over the past few decades--the kappa statistic. A high level of observed agreement among different pathologists can either signify a high level of reproducibility, if agreement by chance is low, or express a low level of reproducibility, if agreement by chance is almost as high as the observed agreement. Therefore, the observed agreement says nothing in itself, unless it is low. The kappa value, however, indicates how much better the observers are compared to a throw of the dice, and therefore gives the real credit to the agreement which was found. We have developed a user-friendly computer program for calculating inter- and intra-observer agreement of 2 or more observers. By calculating associations between different categories and different observers, the statistic furthermore obtains a function close to the parameter of accuracy. We recommend the use of the above method before a set of nominal or rank scale parameters are used for deciding prognosis and treatment of patients. By submitting a diskette the computer program will be available at no cost.

Histological Techniques↗
PubMed1989

Histological evaluation of prostatic cancer. 1. Reproducibility of tumour type.

It has been claimed that the histological type of prostatic carcinoma bears influence on the prognosis of the patient, and that different treatments have to be considered for different types of tumours. The primary aim of this study was to evaluate the reproducibility of the histological criteria for the ordinary acinic adenocarcinoma and ductal adenocarcinoma. From 85 prospective and consecutive cases of prostatic carcinoma all histological slides were examined on two independent occasions by each of 4 pathologists. The overall inter observer agreement and mean intra observer agreement were 0.69 and 0.74, respectively. The kappa coefficients of these inter and mean intra observer agreements were 0.39 (S.E. = 0.02) and 0.48 (S.E. = 0.08), respectively. Considering a dichotomous classification of pure acinic versus all other types of prostatic carcinoma, an overall inter observer agreement of 0.78 and mean intra observer agreement of 0.84 were found. The kappa coefficients of this dichotomous classification were 0.51 (S.E. = 0.03, inter) and 0.61 (S.E. = 0.11, intra), respectively. It is concluded that the criteria for differentiation between different histological types of prostatic carcinoma need to be improved.

Carcinoma↗
PubMed1989

[Clinical pathology of the glomerulus--from phenomenon to entity. The nodular-lobular lesion].

The nodular lesion in renal glomeruli develops as a localized accentuation of mesangial volume augmentation. First described by Kimmelstiel and Wilson in 1936, it was soon accepted as the characteristic form of glomerular sclerosis in patients with long-term diabetes mellitus. It has for a long time been recognized that lesions very similar to nodular glomerulosclerosis may rarely occur in patients without diabetes. Clinical and pathological investigations of such cases have shown that glomerular nodules can also develop, 1. as a sequal to light chain deposit disease associated with plasma cell dyscrasia (e.g. myelomatosis), 2. in mesangioproliferative and membranoproliferative glomerulonephritis ("lobular" GN) and 3. in some cases of glomerular amyloid deposition. A survey is given of the characteristic light microscopy, ultrastructure and immunopathology of the glomerular nodules in these diseases. The differential diagnosis and pathogenesis is discussed.

Amyloidosis↗
PubMed1987

Blood group ABO and Lewis antigen expression during neoplastic progression of human urothelium. Immunohistochemical study of type 1 chain structures.

The deletion of blood group ABO antigen expression in bladder carcinoma has attracted attention because of its potential as a prognostic parameter. Based on recently produced monoclonal antibodies against blood group antigens, it has become possible to elucidate the carcinoma-associated modulation of these antigens at a molecular level. In this study we have used a panel of monoclonal antibodies (H, Lea, Leb, A, ALeb) that are specific to type 1 chain structures. By the use of an immunohistochemical method, the histologic and cytologic location of these antigens in the urothelium was studied in 25 biopsies from transitional cell carcinomas and compared to 21 previously examined normal biopsies. Urothelial blood group reactivity was compared to Lewis and secretor status. The authors found a series of events associated with neoplastic progression of noninvasive urothelium: a disruption of the orderly stratification of blood group antigens in different cell layers; cytostructural relocation of cytoplasmic antigens to the cell surface; loss of correlation between urothelial blood group antigens and secretor status; and gradual deletion of antigens. In the invasive tissue these events were followed by a total deletion of A and H isoantigens and uniform expression of Lewis b and sialyted Lewis a antigen. These findings indicate that there is a complex modulation of blood group antigen biosynthesis associated with the neoplastic progression of the human urothelium.

ABO Blood-Group System↗
PubMed1987

Ouabain effects on oxygen physiology in anemic lambs.

We studied the effects of anemia and ouabain administration on cardiac function, oxygen physiology, and blood catecholamine levels in nine newborn lambs. We measured oxygen consumption continuously, along with traditional hemodynamic variables. Oxygen transport was calculated. Following baseline measurements, lambs were made anemic (mean hematocrit = 12%) by isovolemic exchange transfusion with Plasmanate, and measurements were repeated. Thereafter ouabain was administered as a 75 micrograms/kg bolus, followed by 30 min of infusion at a rate of 0.05 microgram/kg/min. Measurements were repeated at the conclusion of infusion. Anemia was associated with a heart rate related rise in left ventricular rate of pressure rise, a rise in oxygen consumption, an increase in cardiac output, a decrease in systemic vascular resistance, and a rise in fractional oxygen extraction (oxygen consumption/transport). Following ouabain administration, cardiac output, oxygen consumption, and stroke work fell, but left ventricular rate of pressure rise and the extraction ratio did not change. Serum levels of epinephrine and norepinephrine rose with sustained anemia and ouabain infusion. In this setting, ouabain effects are manifested primarily by alterations in oxygen transport and metabolism rather than by changes in traditional assessments of left ventricular contractile function.

Anemia↗
PubMed1987

Acute renal failure in man: pathogenesis in light of new morphological data.

The pathogenesis of acute renal failure (ARF) in such common conditions as acute tubular necrosis, acute interstitial nephritis, and primary graft anuria (ischemic transplant ARF) is poorly understood. Animal models may not exactly mimic the situation in man and thus human morphologic studies are of particular importance. Non-replacement of individual sloughed tubular cells and simplification of the brush border and basolateral infoldings of tubular cells are prominent morphologic changes which correlate with the presence of renal failure. It is possible that the initial injury inhibits cell membrane synthesis, thus interfering with proximal tubular sodium reabsorption with resulting activation of the renin angiotensin system and afferent arteriolar vasoconstriction. Tubular backleak, tubular obstruction by casts and debris, and decreased glomerular ultrafiltration coefficient may also play a role. Although poorly studied until now, the renal failure in primary graft anuria may have a completely different pathogenesis from that in acute tubular necrosis and acute interstitial nephritis. Cyclosporine nephrotoxicity is an important component of primary graft anuria, as seen in many transplant centers in the 1980's.

Acute Kidney Injury↗
PubMed1987

Malignant arterial hypertension. Relationship between blood pressure control and renal function during long-term observation of patients with malignant nephrosclerosis.

Eleven patients with malignant arterial hypertension and malignant nephrosclerosis, verified by percutaneous renal biopsy, were examined during an observation period of 47 months (median). All patients received antihypertensive therapy. Patients were divided into three groups with regard to development of renal function during the observation period. In two patients (group I), the integrated average blood pressure (IA-BP) was 134/95 mmHg (median) and the calculated creatinine clearance (Ccr) increased from 19 to 56 ml/min (medians). In four patients (group II), IA-BP was 154/102 mmHg and Ccr remained stable-at approximately 60 ml/min. In five patients, (group III), IA-BP was 189/114 mmHg, owing to lack of patient compliance and absence from regular control, and Ccr was reduced from 26 ml/min to less than 5 ml/min. During the first 2 months of antihypertensive therapy, renal function was temporarily reduced in 7 of the 11 patients. It is concluded that effective blood pressure control in patients with malignant arterial hypertension and malignant nephrosclerosis can be accompanied by a considerable improvement, or at least a preservation of renal function.

Adult↗
PubMed1986

Effects of CI-914 in congestive heart failure due to coronary artery disease or idiopathic cardiomyopathy.

The hemodynamic effects of CI-914, a phosphodiesterase inhibitor, were studied in 12 patients with left ventricular (LV) dysfunction who were undergoing diagnostic cardiac catheterization. CI-914 was infused intravenously at a rate of 0.8 to 7.0 micrograms/kg/min for 30 to 60 minutes; hemodynamic values were measured every 10 minutes. No effect was seen in the patient receiving 0.8 microgram/kg/min. At infusion rates of 1.2 to 2.4 micrograms/kg/min, cardiac index increased by 14% (p less than 0.025). At infusion rates of 4.5 to 7.0 micrograms/kg/min, cardiac index increased by 21% (n = 8, difference not significant [NS]). Among 4 patients (group B) with an initial pulmonary artery wedge pressure greater than 20 mm Hg and cardiac index less than 2.5 liters/min/m2, cardiac index increased by 50% (p less than 0.001); it did not change among the 4 patients with an initial pulmonary artery wedge pressure of less than 20 mm Hg and cardiac index of more than 2.5 liters/min/m2 (group A). Although systemic vascular resistance decreased in all 8 patients by 26% (p less than 0.01), the reduction was greater in group B (33%, p less than 0.01) than in group A (16%, NS). Peak +dP/dt increased in all 8 patients by 13% (p less than 0.01). Mean stroke work index increased from 29 +/- 15 to 34 +/- 13 g-m/m2; the double product fell from 101 +/- 31 to 91 +/- 23 (NS). In all 12 patients, a linear correlation between peak venous blood concentration and peak effect on cardiac index, systemic vascular resistance and pulmonary artery wedge pressure was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

[Histopathology of drug and toxin induced kidney lesions].

An overview is presented of the morphologic patterns associated with drug or toxin induced renal lesions. Most prominent are the arteritis, glomerulonephritis, tubular necrosis, renal cortical necrosis, intratubular crystal deposition, acute and chronic interstitial fibrosis, interstitial granulomas and acute renal insufficiency with normal renal histology. Findings are correlated with the nature of the noxious substances. Sources of error arising from the insufficient specificity of the morphological findings and the differential diagnostic considerations are fully and critically presented. The review can serve to direct the recognition of etiologic relationships through the interpretation of morphological findings in the kidney.

Acute Kidney Injury↗