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Biomedical subjects

S Larsen

Publications and source records attributed to S Larsen.

At least 271 records · Page 15Linked to original sources
PubMed1989

Antibiotic prophylaxis in colorectal surgery. Combined doxycycline-tinidazole vs. doxycycline alone.

Single-dose doxycycline was compared with single-dose doxycycline + tinidazole in regard to prevention of septic complications after colorectal surgery, taking into account the type and level of surgery--right or left hemicolectomy, rectal operations and others. The study was performed as a prospective double-blind trial, with randomization in blocks. In colorectal surgery as a whole the combination was found to be more effective than doxycycline alone. When the four surgical blocks were separately considered, however, the difference between the two regimens was found to be mainly due to rectal operations, following which the incidence of abdominal and of perineal wound infections was significantly lower with the combined regimen than with doxycycline alone. The subgroups composed of right-sided or left-sided hemicolectomy or other operations were too small to permit definite conclusions.

Adolescent↗
PubMed1988

Laser Doppler flowmetry in evaluation of lower limb resting skin circulation. A study in healthy controls and atherosclerotic patients.

Laser Doppler flowmetry (LDF) was used to evaluate lower limb resting skin perfusion in sixty subjects divided into four groups: healthy young and elderly controls, and patients with intermittent claudication or critical ischaemia. Measurements were performed in pulp skin containing microvascular AV anastomoses and in the skin of leg and thigh where these shunts are absent. In toe pulp controls and claudicators had higher perfusion values than in leg and thigh skin (p less than 0.01), indicating that the LDF method evaluates flow both in nutritional capillaries, AV anastomoses and in dermal vascular plexa. Elderly controls had higher flux values in the pulp than claudicators (p less than 0.01), and claudicators had higher values than patients with critical ischaemia (p less than 0.01), showing that LDF could differentiate between the clinical groups. Study of reproducibility confirmed that values were reproducible on a given population. Day to day variation was considerable in individual subjects, probably because of changes in sympathetic vascular tone and because of different vascular architecture in the measuring volumes which are only some few mm3. The fact that LDF measures total skin blood flow explains why several papers have found a poor correlation between LDF and methods which mainly evaluate nutritional blood flow. The method is non-invasive, continuous and easy to perform. Laser Doppler flowmetry may have several clinical applications, like evaluating progress of atherosclerotic disease or therapeutic effects of drugs or operations. To increase the reproducibility of resting skin flux measurements local heating of the skin is recommended and the measurements should be performed with an integrating probe, which averages the readings obtained at several positions simultaneously.

Adult↗
PubMed1988

Renal enzyme activities in experimental ochratoxin A-induced porcine nephropathy: diagnostic potential of phosphoenolpyruvate carboxykinase and gamma-glutamyl transpeptidase activity.

Enzyme activities have been measured in needle biopsies from kidneys of pigs fed 1 ppm or 0.2 ppm of ochratoxin A for 1-5 wks. After feeding 1 ppm toxin for 1 wk, the activity of cytosolic phosphoenolpyruvate carboxykinase (PEPCK) was decreased by 40% and remained inhibited until the termination of the experiment (5 wk). The activity of gamma-glutamyl transpeptidase, a brush-border enzyme found in the proximal tubules, was reduced to a similar degree and remained inhibited. The activities of hexokinase, a cytosolic enzyme of general distribution in the nephron, and phosphate-dependent glutaminase, a distal tubule enzyme, were not affected. The biopsy results were confirmed by measurements in renal slices taken at the termination of the experiment, except that biopsy samples showed more variation in enzyme activity and a lower PEPCK activity. A guinea pig antibody against the cytosolic form of PEPCK was used to demonstrate that the mitochondrial form of the enzyme, which accounts for a considerable part of the total cellular activity, was not affected by ochratoxin A. When mitochondrial PEPCK activity present in the cytosolic fraction was accounted for, ochratoxin A was found to reduce PEPCK activity by 70-80%. The increase of ochratoxin A exposure from zero through 0.2 ppm to 1 ppm, which resulted in dose-dependent activity decrease of PEPCK and gamma-glutamyl transpeptidase, was accompanied by dose-dependent decrease of renal function, as measured by a reduction of maximal tubular excretion of para-aminohippurate per clearance of inulin (TmPAH/CIn) and an increase in glucose excretion. This suggest that these enzymes are sensitive indicators of ochratoxin A-induced porcine nephropathy. Assuming that porcine nephropathy represents a valid model of endemic (Balkan) nephropathy in humans, the measurement of cytosolic PEPCK and gamma-glutamyl transpeptidase activity in the kidney could be a sensitive test for ochratoxin A-induced disease in humans.

Animals↗
PubMed1988

Do contrast media aggravate Fanconi's syndrome in rats? A comparison of diatrizoate, iohexol, and ioxilan.

Urine profiles (albumin, glucose, N-acetyl-beta-D-glucosaminidase [NAG], lactate dehydrogenase [LDH], L-gamma-glutamyltransferase [GGT], sodium, and phosphate) were followed for seven days after intravenous (IV) administration of either diatrizoate, iohexol, ioxilan, or saline in 24 Wistar rats with a tubular dysfunction induced by IV sodium maleate. Ioxilan and saline had a similar effect on albumin excretion, iohexol had an intermediate effect, and diatrizoate increased it significantly from day 2 to day 7. Glucosuria was significantly greater after diatrizoate than after the nonionic contrast media (CM) or saline. Diatrizoate delayed normalization of enzymuria, whereas iohexol and ioxilan did not. None of the CM affected urinary sodium or phosphate excretion. It is concluded that Fanconi's syndrome is significantly aggravated only by diatrizoate.

Animals↗
PubMed1988

Urine profiles following intravenous diatrizoate, iohexol, or ioxilan in rats.

The effects of intravenous diatrizoate, iohexol, ioxilan, or saline on albumin, glucose, sodium and the enzymes N-acetyl-beta-D-glucosaminidase (NAG), lactate dehydrogenase (LDH), and L-gamma-glutamyltransferase (GGT) in the urine of 24 normal Wistar rats were followed for seven days. During the first two hours after administration of diatrizoate, all profile components changed markedly; the albumin excretion was significantly greater than following ioxilan and iohexol; glucose, LDH, and GGT excretions were significantly greater than following ioxilan. Iohexol and ioxilan caused a higher excretion of albumin, LDH, and GGT than saline. Iohexol also increased glucose and sodium levels. Glucose and GGT were significantly higher following iohexol than following ioxilan. Both high osmolar and low osmolar contrast media may cause temporary glomerular and tubular damage. Urine profile components are affected most by diatrizoate, less by iohexol, and least by ioxilan.

Animals↗
PubMed1988

Withdrawal reactions to diazepam in combined imipramine/diazepam treatment of primary nonagitated depressed outpatients.

Twenty-seven outpatients who had primary nonagitated depression that had been treated for 3.5 months with imipramine were included in the study. Of these, 14 patients were given additional diazepam treatment (10 mg/day) and 13 patients got placebo. The additional medication was stopped, and withdrawal reactions were observed after two weeks. The depression scores (both global evaluation and CPRS) increased significantly in the diazepam group, without any changes in the placebo group. Eleven patients in the diazepam group and four in the placebo group reported their condition as impaired after discontinuing their additional medication. Four patients in the placebo group and none in the diazepam group reported improvement. The level of working activity decreased significantly in the diazepam group and increased in the placebo group. The serum level of imipramine decreased in the placebo group (P = 0.07), but not in the diazepam group. Serum levels of desipramine decreased significantly in both groups (P less than 0.05). Our study indicates that the discontinuation of diazepam, even when given in moderate dosage over a relatively short period of time, may cause withdrawal reactions in combined antidepressant/diazepam treatment. This may be caused by a possible tendency for the depression to become chronic. Such chronicity may be the reason for secondary dependency to diazepam.

Clinical Trials as Topic↗
PubMed1988

Nebulised beclomethasone dipropionate in recurrent obstructive episodes after acute bronchiolitis.

Forty four children with recurrent obstructive episodes after acute bronchiolitis in infancy were treated with nebulised beclomethasone dipropionate or placebo for eight weeks in a randomised double-blind study. They were seen monthly for a year afterwards, and also if they had acute respiratory illnesses with or without bronchopulmonary obstruction. The two treatment groups were well matched. The children receiving active treatment had significantly fewer symptomatic respiratory illnesses and fewer episodes of bronchopulmonary obstruction during the follow up period. The children given placebo had significantly higher obstructive scores during the study period, and they were treated with inhaled beta 2 agonists and theophylline for longer periods of time during the follow up period. The results suggest that nebulised beclomethasone dipropionate may have prolonged effects on subsequent asthmatic symptoms after termination of treatment in children with recurrent obstructive episodes after acute bronchiolitis.

Acute Disease↗
PubMed1988

Bladder tumor staging by transurethral ultrasonic scanning.

To determine tumor stage, 115 bladder cancer patients with cystoscopic suspicion of invasion underwent transurethral ultrasonic scanning. Seventeen patients who had received radiotherapy were excluded because it proved impossible to differentiate between tumor and irradiation sequelae. Of the remaining 98 examinations, 4 (4.1%) were inconclusive, 73 tumors (74.5%) were correctly staged, 16 tumors (16.3%) were overstaged and 5 tumors (5.1%) understaged. Transurethral ultrasound is regarded a useful supplement to cytoscopy and biopsy in staging of bladder tumors suspected of invasion.

Biopsy↗
PubMed1988

Pancreatic hormone secretion in chronic pancreatitis without residual beta-cell function.

Hormonal responses (glucagon, pancreatic polypeptide and somatostatin) to iv glucagon, iv arginine, and ingestion of a mixed meal were investigated in 6 patients with insulin-dependent diabetes secondary to chronic pancreatitis without beta-cell function, in 8 Type I (insulin-dependent) diabetics without beta-cell function, and 8 healthy subjects. No significant differences were found between the two diabetic groups regarding glucagon responses to arginine and meal ingestion. In the patients with diabetes secondary to chronic pancreatitis compared with Type I diabetics and normal controls, the pancreatic polypeptide concentrations were significantly lower and somatostatin concentrations were significantly higher after glucagon, arginine and a mixed meal. Thus, pancreatic glucagon secretion was preserved in patients with insulin-dependent diabetes secondary to chronic pancreatitis, having no residual beta-cell function. These findings suggest that pancreatic glucagon deficiency is not absolute in insulin-dependent diabetes secondary to chronic pancreatitis. A high level of somatostatin may contribute to a lower blood glucose level in patients with chronic pancreatitis.

Adult↗
PubMed1988

Maintenance of high-energy brain phosphorous compounds during insulin-induced hypoglycemia in men. 31P nuclear magnetic resonance spectroscopy study.

31P nuclear magnetic resonance (NMR) spectroscopy allows noninvasive studies of cerebral energy-rich phosphorous compounds in humans. In an attempt to characterize the relationship between peripheral blood glucose concentrations and whole-brain phosphate metabolism during insulin-induced hypoglycemia, 31P NMR spectra were obtained before and after intravenous injection of insulin (0.15 IU/kg body wt) in six men. Compared with prehypoglycemic measurements, no significant changes were found in brain content of Pi, sugar phosphates, phosphocreatine, phosphodiesters, and ATP, and brain pH remained constant during the experiment. These results show that the integrated brain profile of energy-rich phosphorous compounds is unaffected by experimental insulin-induced hypoglycemia in humans.

Adenosine Triphosphate↗
PubMed1988

Straight ileoanal anastomosis with preserved anal mucosa for ulcerative colitis and familial polyposis.

Thirty-two patients were treated with colectomy, mucosal proctectomy, and straight ileoanal anastomosis. Mucosal dissection was performed from the abdominal side, and an anal mucosal brim of 1-2 cm was preserved. Diverting ileostomy was not used, and four patients developed anastomotic leak with pelvic sepsis. Three patients had take-down of the anastomosis for reasons related to the operative method. The remaining patients are all completely continent day and night and have a median stool frequency of 6/24 h 1 year after the operation. The frequency was significantly higher in patients with ulcerative colitis (UC) than in patients with familial polyposis (FP). No dysplasia, ulceration, or stricture formation was found in the preserved mucosa in the UC patients. Regrowth of polyps in the mucosal brim occurred in 10 of 13 FP patients, with atypia in 1. The FP patients had more late complications attributed to extracolonic manifestations of the FP disease.

Adenomatous Polyposis Coli↗
PubMed1988

Evaluation of endoscopic laser Doppler flowmetry for measurement of human gastric blood flow. Methodologic aspects.

Endoscopic measurement of gastric blood perfusion by laser Doppler flowmetry (LDF) has been evaluated in 28 patients and 15 healthy volunteers. During the recordings it was necessary to keep the probe in light contact with the mucosa to obtain stable curves and to avoid artificial Doppler signals caused by relative movements between the gastric wall and the probe. Gastric distention by air insufflation did not influence the recorded flow level significantly when air insufflation was moderate. The intravenous injection of 0.6 mg atropine did not cause any significant alteration in recorded blood flow, and this drug may be used as premedication before endoscopic blood flow measurements. Recordings with both 4- and 12-kHz bandwidth of the LDF instrument showed a relative constant relationship for different flow levels, the flow values measured with 12 kHz being about twice the corresponding values measured with 4 kHz. With 12-kHz bandwidth more of the disturbance signal is recorded, which makes analysis of endoscopic recorded flow curves difficult and inaccurate. It is therefore recommended to use 4-kHz bandwidth during endoscopic measurements in conscious humans. Blood flow measurements from both sides of the gastric wall were consistently of the same order of magnitude (r = 0.91), and the endoscopically recorded output signal increased in three of five patients when a reflecting mirror was placed at the serosal side. The results indicate that endoscopic LDF usually represents blood perfusion in all layers of the gastric wall.

Adult↗
PubMed1988

Colorectal adenomas and food. A prospective study of change in volume and total mass of adenomas in man.

In an endoscopic population screening study for detection of colorectal polyps the diet was registered before ascertaining whether polyps were present. Polyps less than 5 mm in diameter were followed up for 2 years before removal and histologic diagnosis. The relative risk of an increase both in the volume of registered adenomas (excluding new adenomas) and in the total mass of adenomas (including new adenomas) showed a trend towards an inverse relationship with intake of dietary fiber, non-fiber carbohydrate, and cruciferous vegetables, reaching the significance level only for intake of dietary fiber for increase of adenoma volume in men. A trend towards a positive relationship between growth and total fat intake was more inconsistent, although the significance level was reached for the relative risk of increase in adenoma mass for men. These prospective observations with regard to polyp-bearing individuals agree with previous incidence and prevalence data that have indicated a relationship between dietary habits and colorectal carcinogenesis.

Adenoma↗
PubMed1988

Operative treatment of ulcerative colitis: conventional proctectomy with Brooke ileostomy versus mucosal proctectomy with ileoanal anastomosis.

Fifty-four patients with ulcerative colitis were operated on during a 3-year period; 35 had conventional proctectomy and Brooke ileostomy, and 19 had mucosal proctectomy, performed from the abdominal side, leaving 1-2 cm of the distal anal mucosa, and a straight ileoanal anastomosis (IAA) without diverting ileostomy. There were no operative deaths. In the ileostomy group 19 (54%) of the patients had a total of 38 reoperations: 10 laparotomies and 28 revisions of a perineal sinus. Three (16%) of the IAA patients had a total of five reoperations: four laparotomies and one closure of a loop ileostomy. All IAA patients had perfect continence day and night and a median stool frequency of 7.5/24 h 1 year after the operation. Ileostomy patients had significantly longer time out of work, and more urinary, sexual, and social dysfunctions than the IAA patients. After 2-3 years' follow-up study, all differences in results are greatly in favour of the ileoanal procedure.

Adult↗