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Biomedical subjects

S Nilsson

Publications and source records attributed to S Nilsson.

At least 217 records · Page 12Linked to original sources
PubMed1995

Continuous monitoring of energy metabolites using microdialysis during myocardial ischaemia in the pig.

A diagonal branch of the left anterior descending artery was occluded for 80 min. One microdialysis probe was inserted in the ischaemic area and two in the non-ischaemic areas. In six animals radiolabelled microspheres were injected before and during ischaemia and after reperfusion to monitor flow. Arterial and pulmonary artery pressures, pulmonary capillary wedge pressure and cardiac output were followed-up. Radiolabelled microsphere distribution confirmed the reduction of myocardial blood flow during coronary artery occlusion, with flow returning to normal values upon reperfusion. Rate pressure product as an index of heart work was stable throughout the 80 min ischaemic period, but increased at reperfusion. Dialysates from non-ischaemic tissue showed stable baseline values. In ischaemic tissue, lactate increased by 300% and pyruvate levels decreased by 50% within 15 min. Adenosine increased rapidly five-fold, but started to decline after 15 min of ischaemia. Inosine showed a slower but a marked 20-fold increase, decreasing at the end of the ischaemic period. Hypoxanthine increased five-fold during the first 30 min. Finally, guanosine showed a slow increase to about four times above basic values. Microdialysis was an excellent tool for the continuous monitoring of myocardial metabolites during ischaemia. Adenosine appeared to be a more sensitive marker of early ischaemia than lactate, although interestingly, adenosine levels had decreased already after 15 min, most probably due to intracellular accumulation of protons and Pi.

Adenosine↗
PubMed1995

Relationships between defecographic findings, rectal emptying, and colonic transit time in constipated patients.

The relations between defecographic findings, rectal emptying, and colonic transit time were analysed in 80 constipated patients (median age 49 years, range 22-87). Patients were classified into three clinically defined groups (slow transit, outlet obstruction, and a mixed group). Rectal evacuation was evaluation was evaluated by computer-based area calculation. There were no differences in defecographic findings except that evacuation was less efficient in the slow transit group compared with the mixed group (p < 0.01) and with the outlet obstruction group (P < 0.05). Transit time was prolonged in the slow transit and mixed groups compared with the outlet group (p < 0.001). Prominent impression of the puborectalis muscle during straining and the size of a rectocoele correlated with rectal emptying (p < 0.01). Perineal descent, anorectal angles, enterocoele, or intussusception were not significantly related to emptying. Prominent impression of the puborectalis muscle (p < 0.05) and impaired rectal emptying (p < 0.05) were more frequent in patients with prolonged transit time (six or more days). There was no significant correlation between transit time and rectal evacuation in the total study population. There was, however, an inverse relation between these variables (r = 0.40, p < 0.02) when all patients who claimed infrequent defecation (two or fewer/week) were analysed separately. These results did not confirm a direct relation between rectal evacuation and colonic transit time in constipated patients overall. The results are consistent with the suggestion that impaired colonic function may develop secondary to outlet obstruction in some patients.

Adult↗
PubMed1995

Comparison of women with cervical human papillomavirus infection and genital warts. I. Some behavioural factors and clinical findings.

OBJECTIVE: To determine if behavioural factors, other than sexual, differ between women with cervical human papillomavirus infection (CHPI) and those with genital warts (GW). DESIGN: A structured, personal in-depth interview which included details on sexual behaviour, hygiene, gynaecological complaints, and demographical characteristics and a gynaecological examination which included vaginal culture and human papillomavirus (HPV) typing with Southern blot. SUBJECTS: Women (n = 972) who had attended two family planning clinics and one youth clinic for contraceptive advice. RESULTS: Out of this female population 66 (6.8%) were found to have CHPI, 39 (4.0%) had genital warts (GW), and 30 (3.1%) women reported genital warts within the last two years. The women with CHPI had had significantly less education, were more often immigrants, had a vaginal flora change more frequently and were more often smokers than the women with GW. The women with GW reported lower abdominal pain significantly more often, had a leucocyte dominance in the vaginal secretion more often and favoured bathing in a bathtub more than the women with CHPI. After adjustment for sexual behavioural factors the significant difference between the two groups for bathing in a bathtub and lower abdominal pain remained. CONCLUSION: Although both conditions are caused by HPV, there are behavioural differences between women with CHPI and women with CA.

Alcohol Drinking↗
PubMed1995

Ki-67 immunostaining of endometrial biopsies with special reference to hormone replacement therapy.

BACKGROUND: The purpose of this investigation was to evaluate the Ki-67 immunostaining method on formalin-fixed, paraffin-embedded endometrium and to use the method on endometrial biopsies from 30 postmenopausal women treated with 2 mg estradiol and different doses of natural micronized progesterone (50, 100 or 200 mg). METHODS: Two technicians prepared the immunostaining of slides from each of 12 endometrial specimens and 3 different observers estimated the Ki-67 immunostaining. One observer estimated all the slides 3 times on different occasions. The percentage of immunopositive nuclei in glandular epithelium was evaluated. RESULTS: The dominating component of variation for this method was between observers, with a median standard deviation of 20%. A total median variation including all components rendered a standard deviation of 23%. No significant effects of different technicians, preparations, or from the same observer on different occasions were found. In the major part of the biopsies from women on hormone replacement therapy (HRT), only 0-10% of the glandular epithelium was Ki-67 stained. CONCLUSION: Ki-67 immunostaining is an adequate technique to use when evaluating the effects of HRT on the endometrium. The main source of variation is between observers and not the technique of preparing the slides.

Biopsy↗
PubMed1995

Lowering of HDL2b by probucol partly explains the failure of the drug to affect femoral atherosclerosis in subjects with hypercholesterolemia. A Probucol Quantitative Regression Swedish Trial (PQRST) Report.

The aim of the Probucol Quantitative Regression Swedish Trial (PQRST) (n = 303) was to investigate whether probucol (0.5 g BID) added to diet and cholestyramine (8 g BID) could retard progression or induce regression of femoral atherosclerosis in hypercholesterolemic (> 6.86 mmol/L) subjects. Probucol did not induce regression over the 3-year trial period as estimated by change in lumen volume on quantitative arteriography of a 20-cm segment of the femoral artery. In this report we studied in a representative subgroup (n = 72) whether the reduction in HDL concentrations induced by probucol could explain the failure of the drug to be effective. We analyzed the effects of treatment on HDL particle size subclasses. Probucol lowered the relative level of HDL2b, comprising the largest HDL particles, by 53% and the protein concentration of HDL2b by 67%. The protein reduction in HDL was mainly confined to the apolipoprotein A-I moiety. The change in lumen volume correlated significantly with change in HDL, ie, HDL cholesterol (r = .34, P < .01), HDL2 cholesterol (r = .37, P < .01), HDL2b protein (r = .44, P < .001), and the relative HDL2b value (r = .51, P < .001). The corresponding values for relative HDL2b, distribution calculated on the active (n = 35) and placebo (n = 37) groups separately were also significant (r = .39 and .32, respectively; both P < .05). The correlation between drug-induced change in the relative HDL2b concentration and change in atherosclerosis was independent of the alteration in triglyceride concentration and could not be explained by treatment interaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Apolipoprotein A-I↗
PubMed1995

A novel IRMA and ELISA for quantifying cytokeratin 8 and 18 fragments in the sera of healthy individuals and cancer patients.

Cytokeratins 8 and 18 are most frequently co-expressed in simple epithelia and carcinomas. Fragments of these cytokeratins are released into the systemic circulation where they can be quantified and utilized as tumour markers. The present paper reports on a solid-phase sandwich monoclonal immunoassay, considered "epithelial tissue-specific", which recognizes fragments of human cytokeratins 8 and 18 of different sizes (10-50 kD). The evaluated ELISA and IRMA assays exhibited a detection limit of 0.1 microgram 1-1 and characteristically demonstrated a within-assay coefficient of variation (CV) of 1-4% and a between-assay CV of 3-5%. The long-term (300 days) repeatability of lyophilized samples tested in the assay was estimated to have a less than 10% CV. Of apparently healthy individuals, 95% were found to have serum concentrations of less than 0.95 micrograms 1-1. A highly significant difference was found between apparently healthy individuals and pancreatic cancer patients. Patients with metastatic disease showed a sensitivity of 93% and those with local disease 83%, at 95% specificity. This TPAcyk assay revealed good correlation (0.98) with the TPS assay detecting the specific M3 epitope of the tissue polypeptide antigen. The correlation with the long established polyclonal assay of tissue polypeptide antigen (TPA) was estimated to be 0.9.

Animals↗
PubMed1995

Transrectal ultrasonically-guided core biopsies in the assessment of local cure of prostatic cancer after radical external beam radiotherapy.

Fifty-five patients were included in an extended follow-up after radical radiation therapy (RRT) for localized prostatic cancer (T1-3, Nx, M0). Local cure was assessed by a combination of digital rectal examination (DRE), transrectal ultrasound (TRUS) and systematic 'mapping' with TRUS-guided core biopsies (TGCB). After a mean follow-up of 6.8 years, 33% (18/55) of the patients were locally free of tumour, while in 67% (37/55) of cases residual cancer was demonstrated in the biopsies. Endocrine treatment did not influence the local cure rate, nor did the T stage of tumour grade at diagnosis or the cumulative radiation effect (CRE) values within the range of the present study. The sensitivity of DRE and TRUS was low; 37% and 20% respectively, while the specificity of the DRE and TRUS methods was 83% and 94% respectively. The conclusion of the study is that residual tumour was found in the high proportion of biopsied patients nearly 7 years after RRT and that multiple, TRUS-guided core biopsies are mandatory in the assessment of local cure in patients irradiated for prostatic cancer; both DRE and TRUS on their own are less reliable.

Biopsy↗
PubMed1995

External beam radiotherapy of localized prostatic adenocarcinoma. Evaluation of conformal therapy, field number and target margins.

The purpose of the present study was to identify factors of importance in the planning of external beam radiotherapy of prostatic adenocarcinoma. Seven patients with urogenital cancers were planned for external radiotherapy of the prostate. Four different techniques were used, viz. a 4-field box technique and four-, five- or six-field conformal therapy set-ups combined with three different margins (1-3 cm). The evaluations were based on the doses delivered to the rectum and the urinary bladder. A normal tissue complication probability (NTCP) was calculated for each plan using Lyman's dose volume reduction method. The most important factors that resulted in a decrease of the dose delivered to the rectum and the bladder were the use of conformal therapy and smaller margins. Conformal therapy seemed more important for the dose distribution in the urinary bladder. Five- and six-field set-ups were not significantly better than those with four fields. NTCP calculations were in accordance with the evaluation of the dose volume histograms. To conclude, four-field conformal therapy utilizing reduced margins improves the dose distribution to the rectum and the urinary bladder in the radiotherapy of prostatic adenocarcinoma.

Adenocarcinoma↗
PubMed1995

Field displacement during external radiotherapy in prostatic adenocarcinoma treated with radioactive 198Au implants and external irradiation.

The purpose of this work was to study displacement error and internal movements of the prostate during external beam radiotherapy. Verification films in the frontal (n = 194) and lateral (n = 64) portals were investigated in 14 patients treated with radioactive 198Au implants. Displacement errors of two implants were investigated. In seven patients, filling of the rectum and the bladder with contrast medium or isotonic saline was performed during CT investigation for planning purposes to detect movements of the prostate. Most (95%) of the displacement errors were less than 10 mm in the frontal portal and less than 15 mm in the lateral portals. No correlation to the patient's weight was found. The displacement errors were randomly distributed. The spatial relations between the implants were not altered during the treatments. Small movements of the prostate were observed. To conclude, the positioning system employed at present (laser) can be sufficient for the margins used (2 cm). In lateral portals, however, the system did not have the ability to detect a possible systematic displacement error from simulator to accelerator. The intention is to decrease the margins to 1 cm, which will necessitate a better positioning system.

Adenocarcinoma↗
PubMed1995

[Not just for fire. The risk of production and misuse of phosphorus matches. Phosphorus necrosis, abortions and suicides during the latest half of the 1900-century].

The phosphorus match was a useful but poisonous match, used during the last half of the 1900-century. The medical consequences of the match production were far-reaching. The workers, usually women, could be affected by chronic phosphorus poisoning including necrosis in the mandible. The infected mandible had to be surgically removed if the patient should survive. In the last decades of the century the matches were used as a method for abortion and suicide. The misuse can be understood in the light of the widespread social structural changes at the time. With the right dosage, the heads of the matches could be used for abortion but many women died of acute phosphorus poisoning. An extensive debate was going on for decades in the parliament before the production of the phosphorus matches was forbidden in 1901.

Abortion, Spontaneous↗
PubMed1995

MR imaging of contrast-enhanced porcine myocardial infarction. Assessment of reperfusion and tissue viability.

To assess the usefulness of Dy-DTPA-BMA-induced signal reduction, as an indicator of myocardial viability, myocardial infarction was induced in 17 domestic pigs by ligating a diagonal branch of the left anterior descending coronary artery (LAD). In 6 pigs, Dy-DTPA-BMA (1 mmol/kg b.w.) was administered 4 hours after induction of ischaemia. In 5 additional pigs, Gd-DTPA-BMA (0.3 mmol/kg b.w.) and Dy-DTPA-BMA (1 mmol/kg b.w.) were simultaneously injected after 4 hours of ischaemia to ascertain whether Dy-DTPA-BMA counteracted the signal enhancement effect of Gd-DTPA-BMA. A further 6 pigs with infarctions, not administered contrast medium, served as controls. All pigs were sacrificed after 6 hours of ischaemia, and the extirpated hearts were investigated with MR (ex vivo). The concentrations of Dy and Gd were determined in tissue samples from infarcted and non-ischaemic myocardium. The extracellular concentrations of both contrast media were monitored over time during 2 hours in the double-contrast group (in vivo), using a microdialysis technique and analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES). The infarctions demonstrated a high SI in the proton density- and T2-weighted sequences, in both the Dy-DTPA-BMA and control groups, although the former group demonstrated a 3-fold greater concentration of Dy in infarcted compared with non-ischaemic myocardium. Dy-DTPA-BMA did not counteract the Gd-DTPA-BMA-induced enhancement of the infarcted tissue despite a 3-fold higher concentration. This lack of detectable susceptibility effects of Dy may be caused by a loss of cell membrane integrity in the infarcts, resulting in a homogeneous intra- and extracellular distribution of the contrast agent. This hypothesis of an expanded volume of distribution in infarcted tissue was further supported by the microdialysis data, demonstrating a similar extracellular concentration of contrast agents in infarcted and non-ischaemic myocardium, despite a proven 3-fold greater concentration in infarcted tissue samples. To investigate whether Gd-DTPA-BMA-enhanced MR imaging (ex vivo) permits differentiation between reperfused and non-reperfused myocardial infarction, and whether Dy-DTPA-BMA-enhanced MR imaging enables a differentiation between reversible and irreversible myocardial injury following reperfusion, myocardial infarction was induced in 24 domestic pigs (divided into 4 groups) by placing a patched ligature around a diagonal branch of the LAD. Four additional hearts were reperfused after 2 min of brief occlusion, not long enough to cause irreversible injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1995

Dy-DTPA-BMA as an indicator of tissue viability in MR imaging. An experimental study in the pig.

The aim of this study was to investigate whether dysprosium (Dy) induced signal intensity (SI) loss in infarcted tissue in MR imaging. Myocardial infarction was induced in 12 pigs and Dy-DTPA-BMA (1.0 mmol/kg b.w.) was administered i.v. to 6 pigs 4 hours after occlusion and allowed to accumulate in the infarctions for 2 hours. Dy was analysed by inductively coupled plasma atomic emission spectrometry in infarcted and non-ischaemic tissue samples. The remaining 6 pigs, not administered contrast medium, served as controls. The infarctions demonstrated a high SI in the proton density- and T2-weighted sequences in both groups (ex vivo), although the Dy-DTPA-BMA group demonstrated a 3-fold greater concentration of Dy in infarcted compared with non-ischaemic myocardium. The lack of SI loss after Dy accumulation indicates that susceptibility effects are minor or absent in infarcted myocardium.

Analysis of Variance↗
PubMed1995

MR imaging of double-contrast enhanced porcine myocardial infarction. Correlation with microdialysis.

MR imaging was performed to investigate whether Gd-DTPA-BMA-induced contrast enhancement of myocardial infarction is counteracted by Dy-DTPA-BMA. Myocardial infarction was induced in 5 pigs. Microdialysate probes were inserted in ischemic and nonischemic myocardium. Gd-DTPA-BMA (0.3 mmol/kg b.w.) and Dy-DTPA-BMA (1.0 mmol/kg b.w.) were administered i.v. 4 hours post occlusion. The microdialysate was collected every 10 min and measured for Gd and Dy using inductively coupled plasma atomic emission spectrometry. The pigs were sacrificed 2 hours after administration of contrast media. The concentration of both contrast agents was 3 times higher in infarcted myocardium than in nonischemic myocardium. The infarctions displayed high signal intensity in spin-echo sequences ex vivo. This lack of detectable susceptibility effects from Dy may be caused by loss of cell membrane integrity in infarcted tissue as shown by our microdialysate and biopsy data.

Analysis of Variance↗
PubMed1995

MR imaging of gadolinium-DTPA-BMA-enhanced reperfused and nonreperfused porcine myocardial infarction.

To investigate whether Gd-DTPA-BMA-enhanced MR imaging permits differentiation between reperfused and nonreperfused myocardial infarction, myocardial infarction was induced in 12 domestic pigs. In 6 pigs, Gd-DTPA-BMA, 0.3 mmol/kg b.w. was administered i.v. 60 min after the occlusion. In 6 other pigs, the infarctions were reperfused 80 min after the occlusion, followed by injection of Gd-DTPA-BMA after 20 min of reperfusion. Radiolabeled microspheres were used to confirm zero-flow during the occlusion period and reperfusion in the infarcted myocardium. All pigs were killed 20 min after injection of contrast medium, and the hearts were excised and imaged with MR. The Gd concentration was measured in infarcted and nonischemic myocardium by ICP-AES. In the reperfused hearts, the infarctions were strongly highlighted, corresponding to a 5-fold higher Gd concentration in infarcted vis-à-vis nonischemic myocardium. In the hearts subjected to occlusion without reperfusion, there was only a rim of enhancement in the peripheral part of the infarctions.

Animals↗
PubMed1994

The effect of probucol on femoral atherosclerosis: the Probucol Quantitative Regression Swedish Trial (PQRST).

The Probucol Quantitative Regression Swedish Trial tested whether treatment of hypercholesterolemic persons with probucol for 3 years affected femoral atherosclerosis. The primary end point was the change in atheroma volume estimated as change in lumen volume of the femoral artery assessed by quantitative arteriography. Three hundred three patients with visible atherosclerosis were randomized to probucol 0.5 g, twice daily, or to placebo. All patients were given diet and cholestyramine, 8 to 16 g/day. Twenty-nine patients were excluded because of inadequate primary end point measurements. The mean age of the remaining 274 subjects (158 were men) was 55 years. Seventeen percent had intermittent claudication and 24% had angina pectoris. After 3 years, the probucol-treated patients had 17% lower serum cholesterol, 12% lower low-density lipoprotein cholesterol, 24% lower total high-density lipoprotein cholesterol, and 34% lower high-density lipoprotein2 cholesterol levels than control subjects. All lipoprotein differences between the treatment groups remained highly significant during the trial. There was no statistically significant change in lumen volume between the probucol and the control group. Furthermore, there was no difference between the treatment groups with regard to change in arterial edge roughness or amount of aorto-femoral atherosclerosis; neither were there any differences between the treatment groups with regard to change in ST-segment depressions on exercise tests or ankle/arm blood pressure (secondary end points). In the control group, lumen volume increased (p < 0.001) and roughness of the femoral artery decreased (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Arteriosclerosis↗
PubMed1994

Visualization by [3H]resiniferatoxin autoradiography of capsaicin-sensitive neurons in the rat, pig and man.

[3H]Resiniferatoxin autoradiography revealed high densities of binding sites in rat dorsal root ganglia as well as in the superficial dorsal horn of the spinal cord, known to contain the cell bodies and central terminals, respectively, of capsaicin-sensitive, sensory neurons. This binding was fully displaced by non-radioactive resiniferatoxin and was absent following administration of high, neurotoxic doses of capsaicin. The binding thus has the characteristics expected for the vanilloid (capsaicin) receptor. High density, specific resiniferatoxin binding was also observed in pig spinal cord and dorsal root ganglia. Finally, similar high density binding was detected in the dorsal horn of human spinal cord obtained post-mortem. We conclude that [3H]resiniferatoxin autoradiography may afford a novel neurochemical tool to identify capsaicin-sensitive neurons in the central as well as in the peripheral nervous system, to explore the ontogeny of these neurons, and to detect changes in vanilloid (capsaicin) receptor expression under pathophysiological conditions.

Animals↗
PubMed1994

Visualizing vanilloid (capsaicin) receptors in pig spinal cord by [3H]resiniferatoxin autoradiography.

Autoradiographic mapping using [3H]resiniferatoxin (RTX) revealed high densities of vanilloid binding sites over areas (Rexed laminae I and II) in pig spinal cord known to be rich in central terminals of capsaicin-sensitive neurons. Also, high affinity [3H]RTX binding was detected in membranes obtained from the corresponding areas: apparent binding affinity and cooperativity but not the maximal receptor density was influenced by the assay conditions (temperature, buffer composition). No specific binding could be detected in other areas of the spinal cord by either methodology suggesting that the vanilloid receptors are present exclusively on central terminals of the capsaicin-sensitive neurons. We conclude that [3H]RTX autoradiography may afford a novel neurochemical approach to detect localized changes in vanilloid receptor expression.

Animals↗