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P Kruse

Publications and source records attributed to P Kruse.

At least 19 recordsLinked to original sources
PubMed2001

Minor role of oxidative stress during intermediate phase of acute pancreatitis in rats.

Reactive oxygen species have been implicated in the pathogenesis of acute pancreatitis. Few studies have focused on the loss of endogenous antioxidants and molecular oxidative damage. Two acute pancreatitis models in rats; taurocholate (3% intraductal infusion) and cerulein (10 microg/kg/h), were used to study markers of oxidative stress: Glutathione, ascorbic acid, and their oxidized forms (glutathione disulfide and dehydroascorbic acid), malondialdehyde, and 4-hydroxynoneal in plasma and pancreas, as well as 7-hydro-8-oxo-2'-deoxyguanosine in pancreas. In both models, pancreatic glutathione depleted by 36-46% and pancreatic ascorbic acid depleted by 36-40% (p <.05). In the taurocholate model, plasma glutathione was depleted by 34% (p <.05), but there were no significant changes in plasma ascorbic acid or in plasma and pancreas dehydroascorbic acid, malondialdehyde, and 4-hydroxynoneal, and no significant changes in the pancreas glutathione disulfide/glutathione ratio. While pancreas glutathione disulfide/glutathione ratio increased in the cerulein model, there were no significant changes in plasma glutathione, plasma, or pancreas ascorbic acid, dehydroascorbic acid, 4-hydroxynoneal, and malondialdehyde, or in pancreas 7-hydro-8-oxo-2'-deoxyguanosine. Reactive oxygen species have a minor role in the intermediate stages of pancreatitis models.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2000

Anomalous mobility of strongly bound surface species: Cl on GaAs(001)-c(8 x 2)

Although strongly bound chemisorbates at low coverage readily diffuse on metal surfaces at 300 K, they generally do not diffuse on semiconductor surfaces because of a large corrugation in the adsorbate-surface interaction potential. Chlorine chemisorbed on the Ga-rich GaAs(001)-c(8x2) surface has anomalously fast diffusion even though the chemisorption state is tightly bound and highly specific. Simple Hartree-Fock total energy calculations suggest that this diffusion of strongly bound adsorbates can occur at 300 K because there are multiple nearly degenerate adsorbate sites.

Journal Article↗
PubMed1999

Proteases and protease inhibitors in cerulein-induced acute pancreatitis in rats.

BACKGROUND: Proteases and protease inhibitors are important in acute pancreatitis (AP), although little is known about the time course in cerulein-induced AP in the rat. MATERIALS AND METHODS: AP was induced by supramaximal stimulation of cerulein, 10 microgram/kg/h, and during 72 h we measured lipase, amylase, albumin, prekallikrein, factor X, alpha(1)-protease inhibitor, alpha(1)-macroglobulin, alpha(2)-antiplasmin, antithrombin III (all in plasma) and macroscopic and histologic variables. RESULTS: Within 12 h an edematous pancreatitis was evident with peak values of peritoneal exudate, pancreatic wet weight ratio, and plasma amylase and lipase activities. Histologically, edema and vacuolization were prominent already after 3 and 6 h, respectively, while inflammation, necrosis, and total histological score gradually increase to reach peak levels at 48 h. Proenzymes and most plasma protease inhibitors decreased to low levels after 6-12 h followed by a gradual increase. The sequential changes over time indicate that kallikrein - kinin activation, and plasminogen activation are probably early events in cerulein-induced AP in rats. alpha(1)-Macroglobulin and alpha(1)-protease inhibitor gradually decreased during the whole study period, probably being "second line" defense inhibitors. Levels above normal were seen for alpha(2)-antiplasmin and factor X at 48 h, normalizing at 72 h. CONCLUSIONS: These results suggest that protease activation and protease inhibitor consumption occur in cerulein-induced AP in the rat.

Acute Disease↗
PubMed1999

Proteases and protease inhibitors in taurocholate-induced acute pancreatitis in rats.

CONCLUSION: Taurocholate-induced acute pancreatitis (AP) in the rat mimics early necrotizing human pancreatitis. Protease activation and protease inhibitor consumption occur consistent with a two-stage development, and contact-phase activation is a possible primary event in this model. BACKGROUND: Proteases and protease inhibitors have been indicated to play an important role in both human and experimental acute pancreatitis, although little is known about them in rats. METHODS: Three percent sodium taurocholate was infused into the bilio-pancreatic duct to induce AP, and over 0-72 h we measured lipase, amylase, albumin, prekallikrein, factor X, alpha-1-macroglobulin, alpha-2-antiplasmin, antithrombin III, alpha-1-protease inhibitor, and C1-esterase inhibitor (all in plasma) and histologic and macroscopic findings. RESULTS: A severe necrotizing, nonlethal, AP was induced with an early increase in plasma lipase and alpha-amylase activity levels and peritoneal exudate followed by a return to near control levels after 72 h. Histologic score and pancreatic wet weight ratio increased initially and remained high during the observation period. The protease inhibitors C1-esterase inhibitor, alpha-2-antiplasmin, and antithrombin III decreased early, within 0-6 h, whereafter levels normalized. The protease inhibitors alpha-1-macroglobulin and alpha-1-protease inhibitor later gradually decreased over the 72 h.

Animals↗
PubMed1998

Physicians' abdominal auscultation. A multi-rater agreement study.

BACKGROUND: Abdominal auscultation has an important position in the physical examination of the abdomen. Little is known about rater agreement. The aim of this study was to describe rater agreement and thus, indirectly, the value of the examination. METHODS: In a semi-virtual setup 12 recordings of the intestinal sounds from 8 patients with acute abdominal pain and 4 healthy volunteers were presented to 100 physicians. The physicians were asked to characterize the intestinal sounds as normal or pathologic. Fisher's exact test was used for comparison between groups of physicians. RESULTS: Overall, 72% of the answers with regard to healthy volunteers concluded that the sounds were normal (equalling agreement), whereas 64% of answers with regard to intestinal obstruction concluded that the sounds were pathologic (but agreement was higher due to agreement on wrong diagnosis in one case). Bowel sounds from colonic obstruction were diagnosed as pathologic in 94 of 100 answers. In peritonitis disagreement dominated. Specialists in gastrointestinal medicine diagnosed bowel obstruction significantly more poorly than non-specialists in gastrointestinal surgery (P < 0.05). CONCLUSION: Rater agreement in normal subjects and in patients with intestinal obstruction was acceptable for a clinical examination. Abdominal auscultation is a helpful clinical examination in patients with acute abdominal pain.

Abdomen↗
PubMed1996

[Zocor lobby?].

Explore the source record for details and available documents.

Anticholesteremic Agents↗
PubMed1996

Carbon dioxide transport in rats with acute pancreatitis.

CONCLUSION: The production, release, and transport of carbon dioxide from tissues to blood are facilitated both systemically and in the gastrointestinal tract in acute pancreatitis. Red blood cells are responsible for the major exchange and transport of this increase in CO2. The existence of arteriovenous shunting within the intestine is associated with tissue ischemia, which may be involved in the etiology of gut barrier failure in acute pancreatitis. BACKGROUND: Hemodynamic alterations in acute pancreatitis have been described, while little is known about CO2 metabolism. METHODS: Carbon dioxide metabolism was evaluated by virtual values of venoarterial CO2 concentration differences in the early phase after sham operation or induction of acute pancreatitis by intraductal injection of 5% sodium taurocholate in rats. RESULTS: In acute pancreatitis, virtual values of the CO2 concentration increased in arterial RBC at 6 and 12 h as well as in caval and portal vein RBC and plasma. Virtual values of the dissolved CO2 concentration were reduced in arterial and portal vein blood. The increment in blood CO2 concentration related to the increase in CO2 tension from arterial to caval or portal vein valves at constant CO2 tension. The total increment in CO2 concentration from arterial to caval or portal vein blood increased. Whole body oxygen extraction increased, whereas gut oxygen extraction decreased in pancreatitis.

Acute Disease↗
PubMed1996

Continuous phase transitions in the perception of multistable visual patterns.

The phenomenon of stroboscopic alternative motion exhibits five different percepts that are seen with an increase in the frequency of presentation: (a) succession, (b) fluttering motion, (c) reversible clockwise and counter-clockwise turning motion, (d) oppositional motion and (e) simultaneity. From a synergetic point of view the increase in frequency is a control parameter and the different percepts are order parameters with phase transitions in between. The neural network model of Carmesin and Arndt is applied to receive predictions about hysteresis and phase transitions between these order parameters. Empirical data show the different motion percepts (b), (c) and (e) have lognormal distributions. Following the theoretical model, it is argued that there are three different phases, (a), (c) and (e), with two continuous phase transitions, (b) and (d), between them. The experimental data substantially match the theoretical assumptions.

Animals↗
PubMed1996

Frontal gamma-band enhancement during multistable visual perception.

The aim of our study was to find out whether an increase in the gamma band may be related to the reversal phase during viewing of an ambiguous pattern. The present study describes the significant gamma band (30-50 Hz) activity increase in EEG during states of perceptual switching (reversal state). In our experiments the multistability was induced with an ambiguous stimulus pattern, known as stroboscopic alternative motion (SAM). The investigations carried out in 11 subjects included a measuring strategy with three different experimental conditions: (1) recording of spontaneous EEG as baseline; (2) recording of the EEG during naive observation of the ambiguous pattern; (3) recording of EEG during active observation of SAM. The results indicate that the multistable perception is one of the multifold cognitive processes giving rise to 40 Hz enhancement in the entire cortex. The most significant 40 Hz enhancements were measured in frontal areas and can reach increases of 40 to 50% in states of naive and active observations of SAM, respectively, in comparison to spontaneous EEG recordings. The results indicate that the increase of frontal gamma band is related to the destabilization of the perceptual system when viewing multistable patterns.

Adolescent↗
PubMed1993

[CD-ROM--a useful tool for physicians].

The use of compact disc read-only-memory (CD-ROM) at a medical library is described. The introduction of CD-ROM as a reference tool has been a positive experience both for the library staff and the end users (doctors). Medical journals in fulltext, textbooks and special databases are already available on CD-Rom. Future perspectives concerning CD-technology for doctors are discussed.

CD-ROM↗
PubMed1993

Multistable visual perception induces a slow positive EEG wave.

Seven subjects observed a multistable pattern (stroboscopic alternative motion: SAM), and were instructed to press the button immediately after perceptual switching with the aim of detecting some neurophysiological parameters of EEG activity. Our results indicate that the EEG changes observed during multistable perception are similar to the family of event related potentials which we called perceptual switching related positivity. Furthermore, the frequency component of this potential has a similarity to the frequency content of stimulus locked P300.

Adult↗
PubMed1991

Attractors and perceptual field dynamics of homogeneous stimulus areas.

The phenomenon of the wandering point on a blank sheet of paper in serial reproductions is the starting point of an investigation of the perceptual field structure of homogeneous stimulus areas; 609 stimulus points distributed regularly in 21 rows and 29 columns on a DIN A4 sheet were presented successively to 10 subjects and had to be reproduced immediately afterwards in order to establish empirical vector fields. These were subjected to vector-analytic procedures. A method for the decomposition of the measured vector fields into partitions from gradient potentials and circulation potentials is demonstrated. The gradient potentials of the empirical vector fields revealed a highly regular structure with four point attractors near the corners of the sheet. A model calculation of the wandering point in this potential landscape showed results comparable to the empirical phenomenon. The results are discussed in favor of Gestalt theory and against direct perception.

Attention↗
PubMed1990

[Upper abdominal pain and pre-eclampsia--HELLP syndrome].

A 26 year old primiparous woman in the 30th gestational week presented with upper right abdominal pain. Clinical examination revealed direct tenderness under the right curverture, oedema, hypertension and proteinuria. Ultrasound scanning showed a normal gallbladder. Laboratory findings revealed Hemolysis, Elevated Liver enzymes and Low Platelet count. On account of suspected HELLP-syndrome cesarean section was performed. We suggest screening of all pregnant with upper abdominal symptoms suspected for preeclampsia by measuring platelet count and liver enzymes.

Abdominal Pain↗
PubMed1990

[Splenic rupture--a skateboard accident].

A 13-year-old boy presented with persisting abdominal pain after a skateboard accident. Primary clinical and laboratory findings disclosed no signs of intra abdominal bleeding. Ultrasound scanning indicated rupture of the spleen which was confirmed by acute exploratory laparotomy.

Adolescent↗
PubMed1989

Opioid involvement in the perception of pain due to endurance exercise in trained man.

The purpose of this study was to evaluate the role of endogenous opiates in modulating physical performance during dynamic exercise in conscious man. The plasma concentration of beta-endorphin (BEP) and of adrenocorticotropic hormone (ACTH) along with muscle pain (McGuill Pain Questionnaire) were assessed in 17 trained, male runners before and after running the longest possible distance within 12 min (i.e., the Cooper test). Each runner participated twice in the test (double-blind cross-over design), with a 1-week interval--with or without an injection of the opiate antagonist naloxone (0.8 mg i.v.). The average (SEM) distance reached was 3,198 (45) m in the naloxone test and 3,240 (38) m in the placebo test. The BEP increased significantly during the tests by a factor of 4.1 on naloxone and by 2.8 on placebo (from the normal resting averages of 1.7 and 2.1 pmol/l, respectively). The ACTH also increased significantly by a factor of 2.0 on naloxone and 2.5 on placebo (from the normal resting averages of 19.3 and 16.8 pmol/l, respectively). There were no significant differences between the naloxone and the placebo test with respect to the increments of BEP or ACTH by exercise. However, the perception of muscle pain was enhanced with naloxone. The increased perception of pain did not decrease the athletes ability to perform in terms of the distance run. We conclude that endogenous opiates are involved in the perception of pain associated with exhaustive exercise and may subserve psychological rather than physiological functions during exercise.

Adrenocorticotropic Hormone↗
PubMed1989

Development of Trypanoplasma borreli (Mastigophora: Kinetoplastida) in the leech vector Piscicola geometra and its infectivity for the common carp, Cyprinus carpio.

The development of Trypanoplasma borreli in the crop of the leech vector Piscicola geometra was characterized by significant changes in morphology. Immediately after ingestion by the leech, stumpy-shaped T. borreli predominated and numerous dividing specimens were found. This led to long and slender trypanoplasms near the end of the infection. The infection was terminated with complete digestion of the blood stored in the crop of the leech. The longest period of infection observed was 11 days. Trypanoplasma borreli was found only in the crop of the leech. At any time during the infection, T. borreli isolated from P. geometra cause a parasitemia when inoculated into parasite-free carp. There was no difference in morphology or infectivity among T. borreli isolated from various crop regions of P. geometra.

Animals↗