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Biomedical subjects

S L Jensen

Publications and source records attributed to S L Jensen.

At least 73 records · Page 4Linked to original sources
PubMed1991

Effect of substance P on right colonic pressure: a dose response study in pigs.

The purpose of the present investigation was to elucidate the influence and mechanism of the action of substance P (SP) upon intraluminal pressure in proximal porcine colon. In 9 pigs, SP was infused intra-arterially in varying doses from 0.5 to 160 ng/kg/min. Mean baseline colonic pressure was 8.9 mm Hg increasing in a dose-dependent manner to 34.6 mm Hg at an SP dose of 40 ng/kg/min. Hereafter, the colonic pressure remained constant. In other series, SP infusion (5-80 ng/kg) was preceded by infusion of hexamethonium (0.5 mg/kg/min, continuous i.v.; n = 7), atropine (0.01 mg/kg/30 min, i.v.; n = 6), by naloxone (0.01 mg/kg/15 min, i.a.; n = 5) or tetrodotoxin (1 microgram/kg/h, i.a.; n = 7). Atropine significantly inhibited the effect of SP on colonic pressure, whereas the other blockers were without influence on the SP-induced colonic pressure. It is concluded that SP has a potent dose-dependent stimulatory effect upon right colonic intraluminal activity of the pig, mediated partly by atropine-sensitive receptors.

Animals↗
PubMed1991

Changes in gastric emptying in recipients of successful combined pancreas-kidney transplants.

Gastroparesis causes gastric emptying disorders in patients with chronic diabetes mellitus and it results from reduced smooth muscle contractility secondary to autonomic dysfunction. Today there has been little objective evidence of improvement in gastric emptying following correction of both uremia and diabetes by combined kidney-pancreas transplantation. We used gastrointestinal symptom scores, solid gastric emptying tests and electrogastrography to evaluate the effect of combined kidney-pancreas transplantation on gastric emptying in 8 uremic diabetic patients. The mean age of the patients was 40 years (range: 30-51 years) and the mean duration of diabetes was 24 years (range: 16-30 years). The patients had been on dialysis up to 24 months. The pretransplant A1 mean was 6.5 before improving to 4.3 after transplantation. All patients were receiving exogenous insulin. Our study data indicate that uremic diabetics have a high prevalence of symptomatic gastrointestinal dysfunction including abnormalities of gastric emptying and gastric electrical activity. Following transplantation, the gastrointestinal symptomatology improved significantly. Significant improvement in the rate of gastric emptying also correlated with improvement in the symptom complex. Gastric electrical activity also improved during the follow-up period.

Adult↗
PubMed1990

Phagocyte function after splenic autotransplantation.

This study was designed to examine the role of splenectomy and autotransplantation with regard to the leukocyte/differential cell counts and the function of peripheral blood phagocytes. Eleven groups of 40 Wistar male rats in each group either underwent total splenectomies or sham operations. The splenectomized groups underwent autotransplantations with 10% through 90% of the weight of the intact spleen. The leukocyte count and the oxidative burst response of the blood leukocytes were measured in each group. It was shown that a total splenectomy did not alter the leukocyte/differential cell counts. Furthermore, the blood picture remained basically unchanged after an autotransplantation with 10% through 90% of the weight of the intact spleen. The phagocyte oxidative burst response was measured by chemiluminescence. The chemiluminescence response of these cells was reduced after a total splenectomy. The phagocyte oxidative burst response returned to normal levels following an autotransplantation. There was no correlation between the amount of autotransplanted spleen and the degree of the oxidative burst response. These findings indicated that a splenectomy results in a diminished phagocyte oxidative burst response and that a spleen autotransplantation returns this function to normal levels.

Animals↗
PubMed1990

Does survival depend on the amount of autotransplanted splenic tissue?

Susceptibility to Streptococcus pneumoniae infection was studied in 11 groups of rats allocated to sham operation, splenectomy, or splenic autotransplantation of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90% of the removed spleen. Three months later, all rats were exposed intravenously to type 1 Streptococcus pneumoniae (median lethal dose, LD50, for control group). Survivors were killed 13 days after the bacterial challenge. Autopsy showed that more splenic tissue was recovered in rats that received less than 50% splenic tissue compared with those that received 50% or more. More survivors were found among sham-operated rats (47.5%; 95% confidence intervals, 32 to 68) and rats that had 40% splenic tissue implanted (35%; confidence interval, 20 to 54) or those that were found to have regenerated 40% splenic tissue. We conclude that 40% of the spleen should be autotransplanted to protect the rat optimally against infection after splenectomy.

Animals↗
PubMed1990

[Electric stimulation of the autonomic nervous system and vasoactive intestinal peptide and substance P release on the lower esophageal sphincter].

The effect of electrical stimulation of splanchnic and vagal nerve supply to the in vivo isolated porcine LES on the lower esophageal sphincter pressure (LESP) and the secretion of VIP and SP into the venous effluent into the venous effluent of the LES was investigated. Functional integrity of the autonomic nerve supply was assessed by the effect of nerve stimulation on heart rate. Vagal nerve stimulation increased LESP (8-Fold) as well as VIP output (3 Fold) significantly (p less than 0.01) whereas the secretion of SP was unaffected of vagal nerve stimulation. Splanchnic nerve stimulation increased heart rate significantly but was without effect on LESP, VIP, and SP outputs. Atropine partially abolished the effect of vagal nerve stimulation on LESP but the VIP secretion was completely resistant to atropine blockade. Administration of guanethidine was without effect on LESP, VIP, and SP outputs during vagal as well as splanchnic nerve stimulation. It is concluded that VIP acts as a neuro-transmitter since vagal stimulation increase the release of VIP from LESP. However, the finding of a partial atropine resistance of the LESP despite an unchanged release of VIP and SP, suggests that other transmitters participate in vagal activation of LESP.

Animals↗
PubMed1989

Gene amplification associated with the dominant cob-354 cobalt resistance trait in Dictyostelium discoideum.

A DNA amplification is correlated with the dominant, unstable cob-354 cobalt resistance trait in the cellular slime mold, Dictyostelium discoideum. The amplified DNA is present as about 50 copies of an extrachromosomal element. Cells grown under nonselective conditions in the absence of cobalt ions lose both the cobalt resistance trait and all extrachromosomal copies of the amplified DNA. The amplified DNA is transferrable to new genetic backgrounds by parasexual genetic crosses. These results explain the inability to map the cob-354 trait to a linkage group. The chromosomal origin of the amplified DNA is group III or VI. Thus the resistance trait appears to be independent of the previously known cobalt resistance locus, cobA, which maps to group VII. A developmental defect involving the production of multiply-tipped aggregates that do not complete fruiting body formation also is correlated with the presence of the amplified DNA.

Animals↗
PubMed1989

The natural history of symptomatic haemorrhoids.

In order to calculate the prognosis for a person who has developed a first episode of second degree haemorrhoids, 186 patients were randomly assigned to either no active treatment (expectant management) (n = 91) or rubber band ligation (n = 98) and reviewed every 6 months. The median follow-up period was 48 months in both groups with a range from 6-48 months in the banding group and from 18-48 months in the expectant management group. Rubber band ligation was performed at most three times with three weekly intervals. There were 6 treatment failures in the banding group in contrast to 31 in the expectant management group (p less than 0.01). The calculated recurrence rate by actuarial analysis among patients initially cured by rubber band ligation was 33% (95% confidence limits: 23-45) at four years and 61% (95% confidence limits: 48-74) in the expectant management group (p less than 0.05). It is concluded that rubber band ligation of symptomatic second degree haemorrhoids in up to three single treatments at three weekly intervals at the time of diagnosis significantly altered the prognosis without causing significant morbidity. However, 25% of the patients treated by expectant management never developed another episode during the four years observation time.

Adult↗
PubMed1989

Occurrence, distribution and motor effects of galanin in the porcine lower esophageal sphincter.

Specimens from the lower esophageal sphincter (LES) region of the pig were analyzed for galanin-like immunoreactivity (GAL-LI) using radioimmunoassay and immunohistochemistry. The mean concentration of GAL-LI was 3.4 pmol/g tissue. GAL-LI nerve fibers were observed surrounding muscle bundles in the smooth circular muscle layer, and in ganglion cells of the myenteric plexus. Bolus injection of 40-200 pmol/kg of galanin directly into the arterial supply of the resting LES increased the LES pressure (LESP) dose-dependently, whereas slow infusion of 2-100 pmol galanin/kg/min had no effect on resting LESP. The vagally increased LESP was not modulated by simultaneous galanin infusion, and the concentration of galanin in the venous effluent of the LES declined insignificantly during vagal stimulation. It is concluded that galanin may be an important neuropeptide for the modulation of resting LES tone.

Animals↗
PubMed1988

Prognosis after simple incision and drainage for a first-episode acute pilonidal abscess.

During a 3-year period 73 patients were treated consecutively for a first-episode acute pilonidal abscess with simple incision and drainage under local anaesthesia. In all cases the treatment relieved symptoms and all patients returned to work immediately after treatment. Healing per primam occurred in 42 patients (58 per cent; 95 per cent confidence limits: 45-69) within 10 weeks after treatment. These patients had significantly fewer pits and lateral tracts compared with patients who developed excessive granulation tissue after incision and who required definitive surgical treatment later. Nine patients (21 per cent; 95 per cent confidence limits: 10-37) with healing per primam developed recurrence of their pilonidal disease during the prospective follow-up period (median follow-up period was 60 months, range 36-84 months). Actuarial analysis of the data revealed a constant cure rate of 76 per cent (95 per cent confidence limits: 57-95) after 18 months.

Acute Disease↗
PubMed1988

Paget's disease of the anal margin.

A follow-up study of 22 patients with Paget's disease of the anal margin was conducted to determine the prevalence of invasive disease and coexisting visceral carcinomas, cure and survival rates. Seventy-three per cent of the patients suffered from persistent pruritus ani. Seven (32 per cent) patients had malignancy (invasive Paget's disease (n = 5) and coexisting visceral carcinoma (n = 2] and six (27 per cent) developed malignancy (invasive Paget's disease (n = 4) and coexisting visceral carcinoma (n = 2] during follow-up, giving an overall occurrence of malignancies of 59 per cent (95 per cent confidence limits: 36-79). The median follow-up period was 9 (range 0.5-25) years. No difference in length of history could be found between patients with or without malignancy. The estimated cure rate by actuarial analysis among radically treated patients was 64 per cent (95 per cent confidence limits: 43-91) at 1 year and 45 per cent (95 per cent confidence limits: 18-72) at 8 years after primary treatment. The 5- and 10-year crude survival rates of 54 per cent and 45 per cent, respectively, were significantly lower than the corresponding values of 84 per cent and 60 per cent for the normal population (P less than 0.01). Patients with persistent pruritus ani and a perianal skin lesion should be biopsied frequently. If Paget's disease is diagnosed, physical examination of the patient and anorectal region must be done carefully and repeatedly.

Aged↗
PubMed1988

Changes in plasma histamine during orthotopic liver transplantation in the pig.

Hypotension and cardiac arrhythmia are commonly seen during liver transplantation both in man and in experimental animals. The cardiovascular changes may be explained by release of vasoactive substances, e.g. histamine, into the systemic circulation. Abdominal operations are followed by an increased histamine concentration in portal blood. If the liver clears excess histamine from the splanchnic system, an increased histamine concentration should not be found in the systemic circulation. We measured plasma histamine in peripheral arterial blood, blood from the right atrium and portal blood in different phase of liver transplantation in ten pigs. Histamine concentration increased in the portal vein in the anhepatic phase (basal 15.85 pmol/ml to 34.67 pmol/ml, median, p less than 0.05) but no changes were found in arterial or right atrium samples. Venous and later arterial revascularisation were not followed by any changes in histamine concentration in arteria and right atrium samples. We conclude that the transplanted liver can eliminate splanchnic histamine and that histamine is unlikely to be involved in the cardiovascular changes which are seen after revascularisation of the liver.

Animals↗
PubMed1988

Adenocarcinoma of the anal ducts. A series of 21 cases.

The records of 21 patients treated for adenocarcinoma of the anal ducts between 1943 and 1982 were reviewed. The patients were followed until death or current status in April 1987. The median follow-up period was eight months (range, 3 to 144 months). Fifteen patients had an erroneous diagnosis made at first physician visit resulting in a median doctor's delay of 14 months (range, 3 to 24 months) before correct treatment was carried out. Nine of the tumors were localized perianally (ischiorectal space), seven anally, and five in a fistula-in-ano. Tumors localized anally were significantly smaller and had a significantly shorter history than perianally or fistula-in-ano localized tumors (P less than .05 for each localization). Three patients with anal tumors had their diagnosis made accidentally by routine histologic examination of an excised hemorrhoid. First examination revealed distant metastases in 13 patients and follow-up examination revealed regional or distant metastases in seven patients. Modes of treatment were wide local excision (N = 3), abdominoperineal resection (N = 3), colostomy (N = 9), and radiotherapy (N = 2). Twenty of the 21 patients died within 18 months due to the cancer. One long-term survivor was observed; the patient was alive 12 years after local excision of the tumor without evidence of recurrent disease. The crude five- and 10-year survival was only 4.8 percent.

Adenocarcinoma↗
PubMed1988

Long-term prognosis after radical treatment for squamous-cell carcinoma of the anal canal and anal margin.

Sixty-seven of 100 (67 percent) and 24 of 58 (41 percent) apparently radically treated patients with squamous-cell carcinoma of the anal canal (AC) and the anal margin (AM) developed recurrent disease during a median observation time of ten years (range, 0 to 38 years). A significantly higher number of patients treated for AC tumors with local excision had recurrent disease compared with patients treated with abdominoperineal resection (P less than .05). Twenty patients with AC tumors had local recurrence, 21 regional recurrence, and 26 visceral metastases. Eighteen patients with AM tumors had local recurrence, five regional, and one brain metastases. The latest recurrences among AC and AM tumor patients were diagnosed 11 and nine years after primary treatment, respectively. The estimated cure rate by the actuarial method after 15 years was 26 percent and 53 percent for AC and AM tumors, respectively. Thus, if recurrent carcinomas of the anus are to be detected early, frequent life-long control examinations are necessary. It is obvious from this study that, in order to reduce recurrent disease of carcinoma of the anus, new treatment regimens must be tried under controlled circumstances. Surgical therapies alone are clearly insufficient in the treatment of carcinoma of the anus.

Actuarial Analysis↗
PubMed1988

Diet and other risk factors for fissure-in-ano. Prospective case control study.

The findings of a partly prospective case control study of chronic fissure-in-ano conducted in two Danish outpatient clinics are reported. One hundred seventy-four patients with chronic fissure-in-ano were matched by age and sex to outpatients from the same community suffering from benign skin tumors. All subjects were interviewed regarding diet, beverage consumption, occupational exposures, and medical and surgical history. Significantly decreased risks were associated with frequent consumption of raw fruits, vegetables, and whole-grain bread, and significantly increased risks were associated with frequent consumption of white bread, sauces thickened with roux, and bacon or sausages. Risk ratios for consumption of coffee, tea, and alcohol were not significantly different. No statistical associations were found with particular occupational exposures. However, a history of previous anal surgery was reported significantly more often for cases than for controls. Current evidence indicates that anal fissure is likely to result at least partly from an inappropriate diet and that dietary manipulations might reduce the incidence of fissure-in-ano.

Adult↗
PubMed1988

Is the aminoterminal propeptide of type III procollagen degraded in the liver? A study of type III procollagen peptide in serum during liver transplantation in pigs.

The aminoterminal propeptide of type III collagen was monitored in serum during liver transplantation in nine pigs. The aim was to investigate whether removal of the liver causes any changes in the serum concentration of the propeptide. Another connective tissue component, hyaluronan, a glycosaminoglycan known to be degraded in the liver endothelial cells, was also measured. Removal of the liver caused a significant increase in the concentration of the intact propeptide as well as of hyaluronan. Gel filtration confirmed the increase in the amount of intact propeptide. However, another large propeptide-related antigen, eluted near the void volume, appeared in the antigen profile during the anhepatic phase. This peak probably represents the propeptide still attached to the collagen molecule (pN collagen). The findings indicate that the liver is involved in the degradation of the propeptide and of larger propeptide-holding proteins.

Animals↗