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O Nilsson

Publications and source records attributed to O Nilsson.

At least 73 records · Page 4Linked to original sources

[Liver transplantation in neuroendocrine tumors prolongs symptom-free period, might also be a cure].

Several neuroendocrine tumours, such as carcinoids and pancreatic endocrine tumours, may manifest relatively slow tumour growth. The patients may suffer from severe hormonal symptoms, largely due to liver metastases which sometimes are amenable to cytoreductive surgery. If residual tumour after primary tumour resection is multilobar, liver transplantation may be one way to treat hormonal symptoms and possibly prolonging survival. Early long-term outcome of liver transplantation in patients with neuroendocrine tumours suggests prognosis to be more favourable for carcinoids than for endocrine pancreatic tumours. It is suggested that liver transplantation may be appropriate for patients with isolated hepatic tumour disease in the following situations: 1, tumour recurrence after liver surgery for cure; 2, non-resectable liver disease, especially in cases of severe hormonal symptoms; and 3, disease progression after hepatic arterial embolisation and medical therapy. These indications are discussed in the light of three case reports.

Adult↗

Duodenal Helicobacter pylori infection differs in cagA genotype between asymptomatic subjects and patients with duodenal ulcers.

BACKGROUND & AIMS: It is unclear why only a minority of subjects infected by Helicobacter pylori develop duodenal ulcers (DU). The aim of this study was to investigate whether the number and type of H. pylori strains in the duodenum of patients with DU may play a critical role. METHODS: Twenty-one patients with DU and 20 asymptomatic subjects with antral H. pylori infection were studied. Paired biopsy specimens were taken from the antrum and from each quadrant of the duodenal bulb. Analyses included extent of duodenal gastric metaplasia, severity of duodenitis, bacterial density, presence of the cagA gene, and vacuolating cytotoxin activity. RESULTS: H. pylori was cultured from duodenal biopsy specimens in 95% of patients with DU and 80% of asymptomatic subjects. Both groups had a similar bacterial density and proportion of cagA-positive strains in the antrum (86% vs. 75%), but patients with DU had a 20-fold higher density of H. pylori and a higher proportion of cagA-positive strains in the duodenal bulb (81% vs. 30%). Active duodenitis was present only in patients with DU infected by cagA positive strains in the duodenum. CONCLUSIONS: The results suggest that a high density of cagA-positive strains in the duodenum with severe duodenitis are important determinants of DU disease.

Adult↗

Impacted corticocancellous allografts: recoil and strength.

Bone allografts were morcellized using 2 different milling machines (Tracer milling machine and Howex milling machine) producing bone chips with different ranges of sizes. In an in vitro model, each type of bone-graft was impacted with 2 different impaction forces. As the impaction force was released, there was a substantial and rapid recoil of the graft bed. More recoil was seen with the smaller chips and with the harder impacted graft beds. Most of the recoil occurred within the first 10 seconds. Using another similar in vitro model, the same 2 kinds of chips were impacted with 2 different impaction forces, and the subsidence of the 4 different graft beds was measured. There was less subsidence with the bigger type of bone chips and less with the harder impacted graft beds.

Arthroplasty, Replacement, Hip↗

A comparison of the expression of lymphocyte activation markers in blood, bronchial biopsies and bronchoalveolar lavage: evidence for an enrichment of activated T lymphocytes in the bronchoalveolar space.

In this study healthy never-smoking subjects (n = 18) were recruited from a population study. Bronchoalveolar lavage (BAL), blood lymphocytes and bronchial biopsies, analysed both in the epithelium and lamina propria, were stained for T and B lymphocytes, natural killer (NK) cells and different subpopulations of T lymphocytes. In BAL, significantly higher proportions of T lymphocytes (CD3), T lymphocyte activation markers; HLA-DR, CD26+, CD49a+, CD54+ and CD69+, helper T (CD3+4+) and memory helper T lymphocytes (CD4+45RO+29+) and memory T lymphocytes (CD3+45RO+) were found, compared to blood. However, the proportion of IL-2 receptor-positive T lymphocytes (CD25+) was lower in BAL than in blood. A previously described higher ratio of CD3+4+/CD3+8+ in BAL than in blood (3.4 vs 1.7; P = 0.001) was confirmed. In bronchial biopsies, we found significantly higher numbers of CD8+ cell profiles per mm2 in the epithelial compared to the lamina propria compartment. We conclude that healthy never-smoking men have higher levels of activated memory T lymphocytes in BAL than in blood, and that the T-cell subpopulations differ in the epithelial compared to the lamina propria compartment in the bronchial mucosa and these compartments should be analysed separately. It is reasonable to think that there is a gradient from blood to the airway lumen where T cells are recruited from blood to take part in the defense towards damaging agents.

Antigens, CD↗

Intestinal parasites in swine in the Nordic countries: multilevel modelling of Ascaris suum infections in relation to production factors.

In Denmark, Finland, Iceland, Norway and Sweden, 413 sow herds were randomly selected for sampling. Faeces from pigs of 7 age groups/categories were examined for helminth eggs (11,233 individual samples), and an accompanying questionnaire was completed at each visit. In total, 1138 pigs on 230 farms were found to be positive for Ascaris suum. Considerable differences in the occurrence of A. suum could be observed directly for several of 20 independent variables at the herd or category level. However, given that univariate analyses may be severely affected by confounding of covariates resulting in spurious inference, additional multivariate analyses were undertaken. An ordinary logistic regression on Ascaris positive/negative farms showed that Denmark had the highest frequency of infected herds, while Iceland and Finland had the lowest frequencies and that herds using 'late weaning' and 'Class 2' drugs (pyrantel, levamisole) were most often infected. Because many herds were found to be totally negative for A. suum, mixed hierarchical logistic-normal regression models (both the penalized quasi-likelihood and the Markov Chain Monte Carlo methods) were developed for both a full (all herds) and a reduced (the 230 infected herds) data set using either a cut-off of > 0 eggs per gram (epg) or > 200 epg to counter for false-positive egg counts. Estimates for identical models, but where the animal level variance was constrained to the binomial assumption, were also calculated. Significant covariates were robust to model development with 'Age group', 'Country', 'Weaning age', 'Water system' and simple interactions between the latter two and 'Age group' being significantly associated with the occurrence of A. suum, while all variables concerning anthelmintic drug, anthelmintic strategy, floor type, bedding, dung removal, washing and disinfection were not. These findings are discussed in the light of the complex relationship between A. suum and its pig host.

Age Factors↗

Expression of somatostatin receptors in oncocytic (Hürthle cell) neoplasia of the thyroid.

Ten consecutive patients with Hürthle cell lesions of the thyroid (nodule/adenoma/carcinoma) were studied by (111)In-DTPA-D-Phe1-octreotide scintigraphy. Octreotide scintigraphy localized the primary Hürthle cell tumour in eight patients as distinct areas of increased uptake of radionuclide. Two patients with Hürthle cell carcinoma, previously thyroidectomized, had their metastases visualized by octreotide scintigraphy. Northern analyses showed expression of multiple somatostain receptor subtypes. Visualization of the Hürthle cell tumour may be due to a higher expression of somatostatin receptors in the lesions than in surrounding normal thyroid tissue. The tissue/blood (111)In concentration ratios for tumour samples from five patients showed clearly higher values than observed for normal connective tissue, muscle or lymph nodes. A relatively high uptake of (111)In was also observed in goiter tissue, which may lead to misinterpretations. The main indication for octreotide scintigraphy in patients with Hürthle cell carcinoma is suspicion of metastatic disease.

Adenoma, Oxyphilic↗

Comparison of survival between malignant neuroendocrine tumours of midgut and pancreatic origin.

The survival of 64 consecutive patients with disseminated midgut carcinoid tumours was compared in a retrospective study with that of 25 consecutive patients with sporadic malignant endocrine pancreatic tumours treated according to similar surgical principles. The presence of hepatic metastases implied a worse prognosis in neuroendocrine tumours of pancreatic rather than midgut origin. This infers that these tumour types must be separated when treatments are evaluated.

Adolescent↗

Expression of cholecystokinin-B/gastrin receptors in medullary thyroid cancer.

OBJECTIVE: To characterise the cholecystokinin (CCK) receptor subtypes in medullary thyroid cancer by measuring the expression of CCK-A and CCK-B/gastrin receptor mRNA. DESIGN: Open study. SETTING: Teaching hospital, Sweden. SUBJECTS: 6 patients with medullary thyroid cancer. INTERVENTION: Pentagastrin stimulation test and measurement of calcitonin concentration. Biopsy specimens were analysed using reverse transcription polymerase chain reaction (RT-PCR). MAIN OUTCOME MEASURE: Presence of CCK-A and CCK-B/gastrin receptors. RESULTS: All 6 patients with medullary thyroid cancer had positive pentagastrin tests preoperatively. CCK-B/gastrin receptors but not CCK-A receptors were detected by RT-PCR in all six biopsy specimens. By contrast, no CCK receptors were found in normal thyroid tissues or in other thyroid tumours (follicular adenoma, papillary carcinoma, or anaplastic carcinoma). CONCLUSION: The presence of CCK-B/gastrin receptors in medullary thyroid tumours may have important clinical implications.

Adult↗

Standard serum concentrations and normal fluctuations of CEA, CA 50 and CA 242 during twelve months in men and women aged 60-64 years without malignant disease.

OBJECTIVE: To establish standard serum concentrations of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 50 and CA 242 in cancer-free subjects in the age group during which cancers are likely to develop. DESIGN: Prospective study. SETTING: University hospital, Sweden. INTERVENTIONS: Blood samples obtained by venepuncture on four occasions during one year. MAIN OUTCOME MEASURES: Consultation with the Regional Cancer Registry to exclude those who had previously had malignant disease diagnosed or developed cancer during and up to two years after the end of the clinical part of the study. Serum concentrations of CEA, CA 50, and CA 242. RESULTS: The 90th centile was 5.6 ng/ml for CEA, 30.1 U/ml for CA 50, and 24.5 U/ml for CA 242. The mean (SD) serum concentrations were 2.6 ng/ml (2.2) for CEA, 13.2 U/ml (11.4) for CA 50, and 10.6 U/ml (9.6) for CA 242. Serum concentrations of CEA were significantly higher (p < 0.001) among smokers. The intraindividual fluctuations were 16%, 16%, and 14%, respectively. CONCLUSIONS: Serum concentrations of CEA, CA 50, and CA 242 were higher in this study than previously reported, probably because the subjects were older than in other reports. The fluctuations were small. Serum concentrations of CEA were higher in smokers than in non-smokers.

Antigens, Tumor-Associated, Carbohydrate↗

A field survey on the distribution of strongyle infections of horses in Sweden and factors affecting faecal egg counts.

Faecal egg counts were performed during the first quarter of 1995 on samples from 1183 horses of varying breeds, ages and gender on 110 farms in 3 regions of Sweden. The majority of the horses had been treated with ivermectin or pyrantel when stabled the previous autumn. The risk of reinfection with strongyles between treatment and sampling was therefore considered to be minimal. Consequently, the results reflect primarily the occurrence of worms originating from inhibited strongyle larvae refractory to anthelmintic treatment. A total of 922 (78%) individuals were found to shed strongyle eggs, and 15 (14%) of the farms studied had at least one horse infected with Strongylus vulgaris. There was a significant, gradual decrease in faecal egg output in horses originating from the southern to the northern part of Sweden. Horses from studfarms showed significantly higher numbers of strongyle eggs/g faeces (EPG) as compared to those on other types of farms, such as riding-schools and boarding stables. However, there was no correlation between herd size and mean herd EPG. The output of strongyle eggs was highest in horses aged 2 and 3 years. EPG values then declined with increasing age of the horse. Horses treated with ivermectin in the previous autumn showed significantly lower EPG values than untreated horses and those treated with pyrantel pamoate.

Animals↗

Characterization of antibodies to prostate-specific antigen.

Antibodies submitted to the ISOBM TD-3 PSA Workshop were tested for reactivity with free prostate-specific antigen (PSA) and the PSA alpha1-antichymotrypsin (ACT) complex, inhibition of proteolytic activity, recognition of continuous epitopes, and epitope specificity based on complete cross-inhibition studies. The antibodies could be separated into two categories: those recognizing hidden epitopes specific for free PSA, and those recognizing epitopes in both free PSA and the PSA-ACT complex. A large number of distinct antigenic domains were identified both in free PSA and the PSA-ACT complex.

Antibodies, Monoclonal↗

Three isolation techniques for primary culture of human osteoblast-like cells: a comparison.

The culture of osteoblast-like cells of human origin has become an important experimental model in bone biology. We report here a comparison and evaluation of three of the most widely used systems available today: bone marrow stroma cell cultures (BMSC), human osteoblast explant cultures (hOB) and osteoblast explant cultures from collagenase-treated bone (hOBcol). Cultures from 16 bone specimens obtained from various donors were established and their expression of the osteoblast phenotype were then compared in secondary cultures by use of biochemical markers. BMSC had the highest basal and 1,25-dihydroxyvitaminD3 (1,25(OH)2D3)-induced alkaline phosphatase activities in all cell isolations, with levels approximately twice those in explant cultures. Basal osteocalcin secretion was low-to-undetectable in all cell cultures but was detected in 1,25(OH)2D3-stimulated cultures. BMSC produced half of the amount of osteocalcin synthesized in explant cultures. The BMSC cultures also synthesized the lowest amounts of type I collagen, whereas collagen type III synthesis did not differ significantly among the various cultures. When secondary cultures were treated with 100 nM dexamethasone in the presence of ascorbic acid (50 microg/mL) and beta-glycerophosphate (10 mM), cultures deposited calcium mineral into the cell layer within 2-4 weeks. PTH-induced cAMP formation was detected in only 5 of 15 isolations and no consistent isolation-dependent response pattern was seen. We conclude that BMSC cultures differ significantly from explant cultures obtained from the same bone specimen. However, all cultures represent cells which can differentiate further and induce mineralization of the extracellular matrix in response to osteoinductive drugs.

Adolescent↗

No effect of immunosuppression with cyclosporin A detected on bone ingrowth into cancellous allo- and xenografts in the rat.

We studied the effects of the immunosuppressant cyclosporin A on bone ingrowth into allo- and xenografts in the rat using titanium bone chambers. The bone chambers were implanted bilaterally in the tibia. Each rat had one allograft and one xenograft. At 6 weeks the distance of soft tissue and bone ingrowth was measured on histological slides. In xenografts, soft-tissue ingrowth was only slightly less than in allografts, but the ingrown tissue became much less ossified. These differences were unaffected by cyclosporin A treatment, suggesting that the lesser amount of bone formation in xenografts is only weakly associated with T-cell-dependent immune reactions.

Animals↗

Thrombin, but not bradykinin, stimulates proliferation in isolated human osteoblasts, via a mechanism not dependent on endogenous prostaglandin formation.

Osteolysis or osteosclerosis often occurs in bone tissue adjacent to chronic inflammatory processes. Numerous cytokines and inflammatory mediators have been implicated as osteoclast-activating agents, explaining inflammation-induced bone resorption. In many cases, the cause of the sclerosis seen in these lesions is less thoroughly investigated. We have studied the effects of thrombin and bradykinin, 2 inflammatory mediators, on the rate of proliferation in isolated human osteoblasts (hOBs). Thrombin, at and above 1 U/mL, stimulated the rate of thymidine incorporation into hOBs. The absolute cell number also increased, as measured by an assay based on the detection of cell metabolism. A synthetic peptide ligand for the thrombin receptor enhanced the rate of [3H]thymidine incorporation in hOBs, indicating that thrombin-induced proliferation is mediated via the tetheric thrombin receptor. The thrombin-induced proliferation was not affected by indomethacin, excluding prostanoids as mediators of this effect. Bradykinin did not affect either the rate of thymidine incorporation, or number of cells in long-term cultures of hOBs. In conclusion, the inflammatory mediator, thrombin, stimulates proliferation in isolated human osteoblasts probably via the recently described G-protein-coupled tetheric thrombin receptor. Thrombin may therefore be involved as a mediator of inflammation-induced sclerosis and bone formation.

Anti-Inflammatory Agents, Non-Steroidal↗

A genetic framework for floral patterning.

The initial steps of flower development involve two classes of consecutively acting regulatory genes. Meristem-identity genes, which act early to control the initiation of flowers, are expressed throughout the incipient floral primordium. Homeotic genes, which act later to specify the identity of individual floral organs, are expressed in distinct domains within the flower. The link between the two classes of genes has remained unknown so far. Here we show that the meristem-identity gene LEAFY has a role in controlling homeotic genes that is separable from its role in specifying floral fate. On the basis of our observation that LEAFY activates different homeotic genes through distinct mechanisms, we propose a genetic framework for the control of floral patterning.

AGAMOUS Protein, Arabidopsis↗

Intestinal parasites in swine in the Nordic countries: prevalence and geographical distribution.

In Denmark (DK), Finland (FIN), Iceland (I), Norway (N), and Sweden (S), 516 swine herds were randomly selected in 1986-1988. Individual faecal analyses (mean: 27.9 per herd) from eight age categories of swine showed that Ascaris suum, Oesophagostomum spp., Isospora suis, and Eimeria spp. were common, while Trichuris suis and Strongyloides ransomi-like eggs occurred sporadically. Large fatteners and gilts were most frequently infected with A. suum with maximum prevalences of 25-35% in DK, N and S, 13% in I and 5% in FIN. With the exception of the remarkably low A. suum prevalence rates in FIN, no clear national differences were observed. Oesophagostomum spp. were most prevalent in adult pigs in the southern regions (21-43% in DK and southern S), less common in the northern regions (4-17% adult pigs infected), and not recorded in I. I. suis was common in piglets in DK, I, and S (20-32%), while < 1% and 5% were infected in N and FIN, respectively. Eimeria spp. had the highest prevalences in adult pigs (max. 9%) without clear geographical differences. I. suis and Eimeria spp. were recorded for the first time in I, and I. suis for the first time in N.

Age Factors↗

Epidemiology of Anoplocephala perfoliata infection in foals on a stud farm in south-western Sweden.

The egg output and humoral antibody response to scolex antigens of the equine tapeworm Anoplocephala perfoliata were monitored in naturally infected foals by an egg flotation/centrifugation method and an indirect enzyme-linked immunosorbent assay (ELISA). The study was performed on a stud farm in south-western Sweden between May 1994 and April 1995. Sequential blood and faecal samples were taken from 21 foals during their first summer on pasture and until tapeworm eggs were detected. Results were expressed separately for 10 and 11 foals born before and after the end of April 1994, respectively. Increased levels of antibodies were noticed from October and onwards in both groups whereas tapeworm eggs were detected in the faeces of all foals about 4 months later. The antibody response was similar in both groups but it was more pronounced in foals born before April 1994. All foals were treated in March 1995 with an oral paste formulation of pyrantel pamoate at a dose rate of 38 mg/kg bodyweight. Most animals responded to the anthelmintic treatment and one month later, tapeworm eggs were only detected in one out of the 18 foals examined one month after treatment. Thus, the treatment reduced the number of A. perfoliata egg positive horses by 94%. A concomitant decline in antibody levels was also observed. Western immunoblot analysis of sequential individual serum samples showed that at least 10 different scolex antigens in the molecular weight range 10-200 kDa were recognised. Banding intensities, especially of the 10 kDa, 45 kDa and 66 kDa proteins were different in the sequential sera taken during the course of infection.

Administration, Oral↗