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B Poch

Publications and source records attributed to B Poch.

30 records · Page 2Linked to original sources

DNA damage after exhaustive treadmill running in trained and untrained men.

The single cell gel electrophoresis (SCG) assay was used to compare the occurrence of DNA damage in peripheral white blood cells in 6 trained (TR) and 5 untrained (UT) men after exhaustive exercise. The subjects completed an incremental treadmill test until exhaustion (maximal lactate: 12.9 +/- 1.7 in TR and 12.2 +/- 2.5 mmol.l-1 in UT). A clear and significant increase of DNA migration from 2.31 +/- 0.20 (TR) and 2.22 +/- 0.16 (UT) at rest to 2.65 +/- 0.30 (TR) and 3.00 +/- 0.41 tail moment (UT) was found 24 hours after exercise. Noteworthy is that the increase of DNA migration was significantly lower in TR (+ 18.7 +/- 6.8%) compared to UT (+ 35.7 +/- 8.9%). Plasma levels of malondialdehyde (MDA) were not significantly increased in TR and UT after exercise. At rest and 15 minutes after exercise MDA-values were significantly lower in TR compared to UT. In conclusion the present investigation demonstrates the occurrence of DNA damage in white blood cells following exhaustive exercise. This observation may be induced by oxidative stress. Our data suggest that adaptation to training seems to be capable of reducing free radical associated effects, such as DNA damage. Further investigations are needed to clarify the causal mechanisms and biological relevance of exercise-induced DNA damage.

Adaptation, Physiological↗

[Duodenum preserving pancreatic head resection in chronic pancreatitis with inflammatory tumor in the pancreas head].

15 to 30% of the patients with chronic pancreatitis develop an inflammatory mass in the pancreatic head. The leading symptoms of these patients are severe upper abdominal pain and complications of the surrounding organs. From 1969 to 1995, 380 patients were treated with a duodenumpreserving pancreatic head resection. The cause of the disease was alcohol abuse in 81%. 93% of the patients suffered from severe pain with recurrent pain attacks. CT-scan revealed enlargement of the pancreatic head (> 4 cm in diameter) in 79% of the patients. 83% of the patients had an impaired exocrine pancreatic function; 48% of the patients had an impaired glucose tolerance or were diabetic. The hospital mortality was 0.8%; 5% of all patients had to be reoperated. The mean duration of the hospitalization was 13.9 days. 89% of the patients showed an unchanged endocrine function in the early postoperative course. The glucose metabolism was improved in 9%, 2% had a deteriorated function. The duodenum-preserving pancreatic head resection is a procedure with a low postoperative mortality and morbidity without deterioration of the endocrine pancreatic function.

Adolescent↗

Vitamin E prevents exercise-induced DNA damage.

The single cell gel test (SCG test or comet assay) was used to study DNA damage in peripheral white blood cells (WBC) of humans after a single bout of exhaustive exercise and the effect of vitamin supplementation. Human subjects were asked to run on a treadmill until exhaustion and blood samples were taken before and 24 h after the run. A clear increase in DNA strand breakage was observed in the 24-h sample of all probands. A short-term application of multivitamin pills or vitamin E (3 x 800 mg) resulted in a significantly smaller increase of DNA effects in WBC of some probands. When the volunteers were given a supplement of vitamin E (1200 mg daily) for 14 days prior to a run, exercise-induced DNA damage was clearly reduced in all probands. In four out of five subjects, vitamin supplementation completely prevented the induction of DNA damage after exhaustive exercise. Intake of vitamin E for 14 days led to a clear increase in vitamin E serum concentrations. Malondialdehyde (MDA), a marker of lipid peroxidation, was measured in the serum of probands in tests with and without vitamin supplementation for 14 days. MDA concentrations were significantly decreased following vitamin E supplementation but not significantly changed 15 min and 24 h after a run. Our results demonstrate that vitamin E prevents exercise-induced DNA damage and indicate that DNA breakage occurs in WBC after exhaustive exercise as a consequence of oxidative stress.

Adult↗

Effect of acadesine treatment on postischemic damage to small intestine.

Hemorrhagic mucosal lesions are produced during intestinal ischemia and after reperfusion due at least in part to the accumulation and activation of polymorphonuclear leukocytes in the tissue. It has been shown in vitro that adenosine is instrumental in attenuating this pathophysiological process. Acadesine [5-amino-4-imidazolecarboxamide (AICA) riboside], a purine nucleoside analogue, increases the availability of adenosine in the tissue. The aim of the study was therefore to assess the influence of acadesine treatment on neutrophil accumulation, purine metabolism, and mucosal damage after intestinal ischemia and reperfusion. Intestinal ischemia was induced in cats by partial occlusion of the superior mesenteric artery for 2 h. Samples of the small intestine were exercised before and at the end of the hypotensive period as well as 10 and 60 min after reperfusion. Conjugated dienes, myeloperoxidase, and reduced and oxidized glutathione, as well as the purine metabolites, were determined in the tissue samples. The tissue was also examined histologically. Six cats received saline, and six cats were treated initially before ischemia with acadesine (2.5 mg/kg body wt i.v.) over 5 min as a bolus. Thereafter, acadesine (0.5 mg.kg-1.min- i.v.) was given continuously during ischemia and 30 min after reperfusion. Acadesine treatment significantly attenuated the mucosal lesions seen during reperfusion. This improvement was due at least in part to the inhibition of neutrophil accumulation, as judged by low myeloperoxidase levels. The prevention of neutrophil activation resulted most likely from increased adenosine concentrations in the intestinal tissue in the early reperfusion period.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminoimidazole Carboxamide↗

Carcinoid of the ampulla of Vater. Clinical characteristics and morphologic features.

BACKGROUND: Carcinoid tumors of the gastrointestinal tract are most common localized in the appendix, followed by the small intestine, the rectum, and the stomach. The localization of these tumors at the ampulla of Vater is extremely seldom. METHODS: In the present study the authors describe two patients with carcinoid tumors of the ampulla Vater and review 71 previously published cases. RESULTS: Most patients presented with jaundice, but without carcinoid syndrome. Because the tumor grows submucosally, preoperative diagnosis was correct only in 15%. Most tumors were around 2 cm in size. Metastasis to lymph nodes and/or liver was present in 45%. Standard treatment is Whipple resection or local excision in small tumors. CONCLUSIONS: Carcinoid tumors of the ampulla of Vater are an extremely rare clinical entity. Generally, the prognosis is good with a 5-year survival period of 90%.

Adult↗

Free radicals and pathogenesis during ischemia and reperfusion of the cat small intestine.

BACKGROUND/AIM: In spite of the interest in free radicals as mediators of ischemic damage, most information on these species in biological systems is derived from indirect measurements. Our aim was to obtain more direct information concerning sources of free radical production during ischemia and reperfusion. METHODS: We have performed simultaneous measurement of radical generation, purine metabolites, reduced glutathione, neutrophil infiltration and morphological appearance in the cat small intestine in vivo during 60 minutes of ischemia followed by 60 minutes of reperfusion. RESULTS: Radical formation increased abruptly on reperfusion and remained elevated in untreated animals. Inhibition by a monoclonal antibody (IB4) against the neutrophil and by allopurinol treatment was paralleled by improvement of biochemical and morphological parameters. The radicals detected during reperfusion could be divided into one component arising directly from the neutrophils, one due to the xanthine oxidase reaction, and one unknown source. CONCLUSIONS: Neutrophils are a major source of radical production during reperfusion after ischemia. Radicals formed in the xanthine oxidase reaction seem to function as a primer for the neutrophils. The nonsignificant linear correlation between radical formation and morphological appearance suggests that factors other than free radicals are important for the development of intestinal damage after a period of ischemia.

Allopurinol↗

Involvement of neutrophils in postischaemic damage to the small intestine.

Haemorrhagic mucosal lesions are produced during intestinal ischaemia and after reperfusion probably mediated by oxygen radicals. Oxygen radicals react with cell membrane lipids and induce cell damage by peroxidation and induce accumulation of polymorphonuclear leucocytes in the tissue. The aim of the study was to elucidate the involvement of polymorphonuclear leucocytes in post-ischaemic intestinal damage. Intestinal ischaemia was induced in cats by partial occlusion of the superior mesenteric artery. Samples from the small intestine were excised before and at the end of the two hour hypotensive period as well as 10 minutes and 60 minutes after reperfusion. Conjugated dienes, myeloperoxidase, and the purine metabolites were determined in the samples. The tissue was also examined histologically. Seven cats were treated before reperfusion with a monoclonal antibody (IB4) which inhibits leucocyte adherence to endothelial cells and its subsequent activation. After reperfusion myeloperoxidase activity increased and the ischaemic mucosal lesions worsened significantly. IB4 treatment prevented an increase in post-hypotensive myeloperoxidase activity and attenuated the normally observed severe mucosal lesions. We conclude that the severe post-ischaemic lesions are induced by polymorphonuclear leucocytes. Such mucosal injury may be appreciably reduced by blocking leucocyte adherence with IB4.

Animals↗

Oxygen tension, oxygen metabolism, and microcirculation in vasogenic brain edema.

In cold brain injury edema, cerebral pO2, oxygen metabolism, and local CBF were investigated. In randomized groups of 10 rats each, pO2 was measured by polarography using a balanced multiwire surface electrode on the parietal cortex after trepanation. lCMRO2 was approximated by oxygen disappearance rate after sudden complete cerebral circulatory arrest (cervical cuff inflation). Using integrated platinum electrodes, the local CBF was measured by H2 clearance. All data were evaluated on-line by computer. In normal animals we found a regular, normally distributed pO2 histogram in barbiturate and in ketamine anesthesia. Oxygen consumption and local CBF, however, are significantly higher in ketamine narcosis. The local CBF is thereby coupled with metabolic requirements: The more oxygen consumed, the higher the local pO2. In animals 24 hr after cold brain injury, this metabolic coupling is disturbed: In the perifocal edema the pO2 histogram is flat and broad with different mean and median, but with a shifting toward higher oxygen values. Oxygen consumption is reduced; the local CBF, however, is significantly increased with large variations. Also over the contralateral, noninjured hemisphere a decrease in CMRO2 and an increase in pO2 are observed (diachisis). These disturbances with a maximum at 24 hr after injury show a recovery after 72 hr. After infusion of the calcium entry blocker nimodipine a normalization in pO2 distribution was found, combined with an increase in CMRO2. We assume a primary disturbance of oxidative glucose metabolism with uncoupling of metabolic flow control; local CBF and O2 availability are not primarily impaired. Ca2+ may be a main factor in this pathophysiology.

Animals↗

Surgical treatment of pancreas divisum causing chronic pancreatitis: the outcome benefits of duodenum-preserving pancreatic head resection.

Pancreas divisum (PD) represents a duct anomaly in the pancreatic head ducts, leading frequently leading to recurrent acute pancreatitis (rAP) or chronic pancreatitis (CP). Based on endoscopic retrograde cholangiopancreatography, pancreas divisum can be found in 1% to 6% of patients with pancreatitis. The correlation of this abnormality with pancreatic disease is an issue of continuing controversy. Because of the underlying duct anomalies and major pathomorphological changes in the pancreatic head, duodenum-preserving pancreatic head resection (DPPHR) offers an option for causal treatment. Thirty-six patients with pancreatitis caused by PD were treated surgically. Thirty patients suffered from CP, 6 from rAP. The mean duration of the disease was 47.5 and 49.8 months, respectively. The age at the time of surgery was 39.2 years in the CP group, and 27.6 years in the rAP group. Median hospitalization since diagnosis was 18.8 weeks for CP patients and 24.6 weeks for rAP patients. Previous procedures performed in these patients included endoscopic papillotomy (30%), duct stenting (14%), and surgical treatment (17%). The median preoperative pain score was 8 on a visual analog scale. According to the classification of pancreas divisum, 10 patients demonstrated a complete PD, 25 had a functionally incomplete PD, and 1 had a dorsal duct type. The pain status as well as the endocrine (oral glucose tolerance test) and exocrine (pancreolauryl test) function were evaluated preoperatively and early and late postoperatively with a median follow-up time of 39.3 months. There was no operative-related mortality. The follow-up was 100%; 4 patients died (1 from suicide, 1 from cardiac arrest, and 2 from cancer of the esophagus). Fifty percent of the patients were completely pain-free, 31% had a significant reduction of pain with a median pain score of 2 (P < 0.001). Six patients (5 CP, 1 rAP) had further attacks of acute pancreatitis with a need for hospitalization. DPPHR reduced pain and preserved the endocrine function in the majority of patients with pancreas divisum. Therefore, DPPHR is an alternative to other resective or drainage procedures after failure of interventional treatment.

Adult↗

[A case of hemiballism and a case of senile chorea].

Tiapride is potent on anormal movements. Its utilisation for aged persons seems to have good results. An hemiballism at a woman 83 years old had not regressed very much and the reapprenticeship of walking was possible again. The choreic movements of a woman 90 years old had disappeared and the walk was possible again. These two notes show us the possibilities of improvements in acting obtained even for the very old patients and good tolerance of tiapride.

Administration, Oral↗