TNFR1 determines progression of chronic liver injury in the IKKγ/Nemo genetic model.

Death receptor-mediated hepatocyte apoptosis is implicated in a wide range of liver diseases including viral and alcoholic hepatitis, ischemia/reperfusion injury, fulminant hepatic failure, cholestatic liver injury, as well as cancer. Deletion of NF-κB essential modulator in hepatocytes (IKKγ/Nemo) causes spontaneous progression of TNF-mediated chronic hepatitis to hepatocellular carcinoma (HCC). Thus, we analyzed the role of death receptors including TNFR1 and TRAIL in the regulation of cell death and the progression of liver injury in IKKγ/Nemo-deleted livers. We crossed hepatocyte-specific IKKγ/Nemo knockout mice (Nemo(Δhepa)) with constitutive TNFR1(-/-) and TRAIL(-/-) mice. Deletion of TNFR1, but not TRAIL, decreased apoptotic cell death, compensatory proliferation, liver fibrogenesis, infiltration of immune cells as well as pro-inflammatory cytokines, and indicators of tumor growth during the progression of chronic liver injury. These events were associated with diminished JNK activation. In contrast, deletion of TNFR1 in bone-marrow-derived cells promoted chronic liver injury. Our data demonstrate that TNF- and not TRAIL signaling determines the progression of IKKγ/Nemo-dependent chronic hepatitis. Additionally, we show that TNFR1 in hepatocytes and immune cells have different roles in chronic liver injury-a finding that has direct implications for treating chronic liver disease.

Sensation of defecation in patients with spinal cord injury.

STUDY DESIGN: For this study, a descriptive, explorative design was used. OBJECTIVES: As a result of spinal cord injury (SCI) patients may have a partial or complete loss of the sensations of defecation. To compensate this impairment, nurses initiate bowel management programs. Therefore, they need information about sensations of defecation. Accordingly, the research questions explore which sensations of defecation are reported by patients with SCI and whether they can be used to improve bowel care. SETTING: The Gemeinschaftskrankenhaus Herdecke and the Berufsgenossenschaftlichen Kliniken Bergmannsheil in Bochum, Germany. METHODS: A convenience sample of 27 patients with SCI was interviewed using a semistructured questionnaire. For data analysis, the frequency of the reported sensations was counted. RESULTS: The results of the study show that the participants' defecation was indicated by abdominal sensations (n=20) or a prickling sensation (n=11) emerging mainly in the head. Additional signals comprised increased spasticity (n=10), cutis anserina (n=8) and sweating (n=6). Seventeen participants sensed actual defecation and 15 perceived its cessation. Six participants were able to initiate defecating according to their sensations. CONCLUSIONS: The assessment of sensations of defecation in patients with SCI may indicate whether a bowel-management program with a consistent schedule for defecation is needed or if physiological defecation can be trained.

Comparison of two methods for enhanced continuous circulatory monitoring in patients with septic shock.

OBJECTIVE: To compare a modified pulmonary artery catheter (PAC) and pulse-contour analysis by the PiCCO (Pulsion Medical Systems, Munich, Germany) system for continuous assessment of cardiac output in patients with septic shock. In addition, to assess the relationships between an index of global end-diastolic volume (GEDV) derived by the PiCCO system with traditional PAC-derived indicators of filling: central venous pressure; pulmonary artery occlusion pressure; and right ventricular end-diastolic volume (RVEDV). DESIGN: Prospective cohort study. SETTING: Surgical intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: 14 patients with septic shock. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: A significant correlation was found between continuous cardiac output by PAC (CCO(PAC)) and by pulse-contour analysis (r (2) = 0.714, p < 0.0001), accompanied by a bias of 0.1 l min(-1) and a precision of 2.7 l min(-1). The correlation between CCO(PAC) and cardiac output measured by transcardiopulmonary thermodilution was also significant (r (2) = 0.781, p < 0.0001). There was a bias for the two methods of 0.2 l min(-1), and a precision of 2.2 lmin(-1). The GEDV showed no correlation with central venous pressure, pulmonary artery occlusion pressure, or RVEDV. CONCLUSION: In patients with septic shock, the averaged bias in continuous measurement of cardiac output by both a modified pulmonary artery catheter and pulse-contour analysis was small, but variability was large. No correlation was found between GEDV and RVEDV. The clinical importance of different cardiac filling parameters needs further investigation.

Upregulation of group IB secreted phospholipase A(2) and its M-type receptor in rat ANTI-THY-1 glomerulonephritis.

Treatment of rat glomerular mesangial cell (GMC) cultures with pancreatic secreted phospholipase A(2) (sPLA(2)-IB) results in an enhanced expression of sPLA(2)-IIA and COX-2, possibly via binding to its specific M-type sPLA(2) receptor. In the current study, we have investigated the expression and regulation of sPLA(2)-IB and its receptor during glomerulonephritis (GN). In vivo we used the well-established rat model of anti-Thy 1.1 GN (anti-Thy 1.1-GN) to study the expression of sPLA(2)-IB and the M-type sPLA(2) receptor by immunohistochemistry. In addition, in vitro we determined the interkeukin (IL)-1beta-regulated mRNA and protein expression in primary rat glomerular mesangial and endothelial cells as well as in rat peripheral blood leukocytes (PBLs). Shortly after induction of anti-Thy 1.1-GN, sPLA(2)-IB expression was markedly upregulated in the kidney at 6-24 h. Within glomeruli, the strongest sPLA(2)-IB protein expression was detected on infiltrated granulocytes and monocytes. However, at the same time, the M-type receptor was also markedly upregulated on resident glomerular cells. In vitro, the most prominent cytokine-stimulated secretion of sPLA(2)-IB was observed in monocytes isolated from rat PBLs. Treating glomerular endothelial cells (GECs) with cytokines elicited only weak sPLA(2)-IB expression, but treatment of these cells with exogenous sPLA(2)-IB resulted in a marked expression of the endogenous sPLA(2)-IB. Mesangial cells did not express sPLA(2)-IB at all. The M-type sPLA(2) receptor protein was markedly upregulated on cytokine-stimulated mesangial and endothelial cells as well as on lymphocytes and granulocytes. During anti-Thy 1.1 rat GN, sPLA(2)-IB and the M-type sPLA(2) receptor are induced as primary downstream genes stimulated by inflammatory cytokines. Subsequently, both sPLA(2)-IB and the M-type sPLA(2) receptor are involved in the autocrine and paracrine amplification of the inflammatory process in different resident and infiltrating cells.

Bowel management in patients with spinal cord injury -- a multicentre study of the German speaking society of paraplegia (DMGP).

STUDY DESIGN: A descriptive, cross-sectional, multicentre design was used. OBJECTIVE: To analyse bowel management in patients with spinal cord injury (SCI) especially the occurrence of unplanned bowel evacuations and duration of planned bowel evacuation. SETTING: In total, 29 rehabilitation facilities for SCI patients in Austria, Germany, the Netherlands and Switzerland, with a total of 837 hospitalized SCI patients. METHOD: Data were collected by nurses within 1 week in November 2001 using a quantitative questionnaire containing 14 questions. For data analysis, a chi (2)-test was used for differences in the outcome of bowel evacuation procedures associated with different interventions. Stepwise multiple logistic regression was used to analyse the relationship between the outcome of bowel management and the interventions as well as intervening factors. RESULTS: More unplanned bowel evacuations were associated with usage of oral laxatives (n=444, P<0.001) as well as bowel evacuation every day (n=270, P<0.05) or every second day (n=368, P<0.05). The outcome of less unplanned bowel evacuations was associated with manual removal of stool combined with digital stimulation (n=35, P<0.05) and spontaneous bowel evacuations (n=104, P<0.001). Short duration of bowel evacuation (<60 min) was associated with manual removal of stool (n=64, P<0.05), the sitting position at defecation (n=494, P<0.001) and low frequency of bowel evacuation (>or=3 days) (n=638, P<0.05). Duration >60 min was associated with the use of oral laxatives (n=444, P<0.001) and complete loss of sensory function (n=349, P<0.05). Stool of hard consistency was associated with the manual removal of stool (n=64, P<0.001), the manual removal of stool in combination with digital stimulation (n=53, P<0.001) and the sitting position at defecation (n=494, P<0.05). Stool of soft consistency (n=341) was associated with the complete motor lesion (n=443, P<0.05). CONCLUSION: Manual removal of stool was combined with low risk of unplanned bowel evacuations and short duration of evacuation time. These results are useful to improve the outcomes of bowel management in SCI patients.

Laser atomic absorption spectrometry of excited Hg in a discharge applying sum frequency mixing of two diode lasers (preliminary results).

Wavelength modulation diode laser atomic absorption spectrometry is applied to the detection of atomic mercury. Transitions from metastable energy levels highly populated in a radio-frequency discharge are induced with laser diodes by use of nonlinear techniques. The wavelength of one strong transition at 365.119 nm with a high oscillator strength is obtained by sum frequency generation of two diode lasers. The cold vapor technique is used to transfer ionic into atomic mercury. The mercury in the vapor phase is transported by an argon stream into the discharge tube. From the time-dependent absorption signals detection limits of 100 ng/L are achieved at this state of research.

[Premedication and preoperative fasting in pediatric anesthesia. Results of a survey]. / Prämedikation und präoperative Nahrungskarenz in der Kinderanästhesie. Ergebnisse einer Umfrage.

This study evaluates the current practice of premedication and preoperative fasting in pediatric anaesthesia in Germany. A total of 90 questionnaires were mailed to randomly selected hospitals with departments or sections of anaesthesiology and pediatric surgery. 71 questionnaires were returned and analysed (reply rate 79%). 60% of the responding hospitals start premedication between the ages of 3 and 12 months and 32% between 1 and 2 years of age. Premedication ist most often given orally (64%), followed by rectal (29%) and intranasal (3%) routes. Midazolam is used by 96% of the respondents as the primary sedative premedication. Alternatively, promethazine and chloraldhydrate are most frequently used. Anticholinergic drugs are given routinely by 21% of the respondents. For the apprehensive child intramuscular ketamine is most often used (33%), followed by intranasal midazolam (22%), rectal midazolam (19%) and rectal thiopentone or methohexitone (13%). For children less than 1 year of age 63% of the hospitals restrict clear liquids 2 hours and 34% 3 or 4 hours before anaesthesia. 64% of the respondents require abstinence from milk for 4 hours and 30% for 6 hours prior to surgery. For children older than one year of age fasting period requirements for clear liquids were 2 hours (34%), 3 hours (27%), 4 hours (30%) and 6 hours (9%). For children over 1 year of age the majority allow solid food or milk up to 6 hours prior to anaesthesia (68% and 63%, respectively). The survey shows that premedication is started during the first two years of age by nearly all responding hospitals. Oral or rectal midazolam is the most frequently used premedication regimen. Preoperative fasting guidelines vary.

Weak binding and removal of extrinsic proteinase activities of myelin membranes.

The concurrent release of myelin basic protein (MBP) and extrinsic proteinases from isolated myelin membranes by aqueous solvents of high ionic strength is considered circumstantial evidence of a presumptive mutual interaction in situ. The joint release of proteins and proteinases from myelin membranes of bovine brain, depending on the ionic strength of aqueous solvents, was therefore examined; 25 mM Tris buffer released an average 1.4% of total myelin protein. It was attributable to about 25 different electrophoretic bands, but no apparent MBP. However, the extract potently mediated the limited proteolysis of added MBP at pH 4.0, 5.6, and 9.0. Because of the pH and the effects of specific inhibitors, proteolysis appears to be owing to activities of cathepsin B and D, and an alkaline metalloproteinase. The subsequent extraction of myelin membranes with buffered 300 mM NaCl released an additional 20% of total myelin protein, mainly MBP. The extracts, unlike those of untreated myelin membranes, no longer cleaved MBP at pH 5.6 and 9.0, and did so only slightly at pH 4.0. The results indicate that the bulk of soluble myelin-associated proteinases is much less tightly bound than MBP. The weak binding of the former and the prevalence of lysosomal cathepsin B- and D-like activities suggest that during their isolation, myelin membranes may adsorb soluble cellular proteins of tissue homogenates. At any rate the washing of myelin membranes with dilute buffer was found to largely remove soluble proteinase activities that are otherwise associated with salt-soluble MBP of myelin.

Expression of vascular cell adhesion molecule-1 (VCAM-1) in the aortae of hypercholesterolemic rabbits with high (HAR) and low (LAR) atherosclerotic response.

Recently we have described two strains of rabbits, one with a low (LAR) the other with a high (HAR) atherosclerotic response to dietary hypercholesterolemia. After feeding a cholesterol diet for 12 weeks, HAR rabbits developed atherosclerotic lesions throughout the entire aortic arch and thoracic aorta. In contrast, the lesions in LAR rabbits were mainly confined to the aortic arch. Presently we studied the cellular composition and expression of vascular cell adhesion molecule-1 (VCAM-1) in aortic lesions and in the uninvolved aorta of cholesterol fed HAR and LAR rabbits. Plasma cholesterol levels were 1106 +/- 160 and 1152 +/- 232 mg/dl in HAR and LAR rabbits, respectively, and the distribution of cholesterol among the lipoprotein fractions was similar after 16 weeks of 0.5% cholesterol feeding. In analogy to our previous findings, in the HAR rabbits more than 70% of the aorta (aortic arch and thoracic aorta) was covered with lesions, whereas in the LAR rabbits the lesions were seen in the aortic arch only and covered less than 20% of the total aortic surface. The cellular composition of aortic lesions was defined using specific antibodies to macrophages, smooth muscle cells, T lymphocytes and Ia expressing cells. All these cellular elements were represented in lesions derived from both strains of rabbits. We also examined the expression of VCAM-1 in the aorta of HAR and LAR rabbits after cholesterol feeding. In the aortic arch, a positive reaction for VCAM-1 was found in lesions from both strains of rabbits. The staining was seen in the endothelium and within the lesion, mainly at its base. In the thoracic aorta of HAR rabbits, VCAM-1 expression was found in all lesions examined. In the thoracic aorta of LAR rabbits, VCAM-1 expression was seen in an occasional very small lesion found at the ostium of an intercostal artery. These results show that the VCAM-1 gene is expressed in the LAR rabbits, but its induction is perhaps attenuated.

Cortical cathepsin D activity and immunolocalization in Alzheimer disease, critical coronary artery disease, and aging.

The activity and immunocytochemical localization of cathepsin D in the frontal cortex were investigated in patients with Alzheimer disease (AD) and two groups of nondemented subjects; individuals with critical coronary artery disease (cCAD; > 75% stenosis) and non-heart disease controls (non-HD). The cathepsin D activity significantly increased with age in the non-HD population. No such age-related increase was observed in either AD or cCAD. Enzymatic activity was significantly increased in only the midaged, but not the older AD and cCAD subjects compared to controls. Immunocytochemical reactivity paralleled cathepsin D enzymatic activity. Frontal cortex neurons displayed an increased accumulation of cathepsin D immunoreactivity in aging (non-HD controls) with a further increase in cCAD, especially in the midaged group. Such immunoreactivity was markedly increased in AD. There was also an apparent age-related increase in the number of cathepsin D immunoreactive neurons in the non-HD population and a disease-related increase in only the mid-aged AD and cCAD subjects compared to controls. Senile plaques (SP) occurred in all AD patients, many cCAD, and a few of the oldest non-HD subjects, and they were immunoreactive to cathepsin D in each group. The data suggest a possible relationship between activation of cathepsin D and SP formation in AD, cCAD, and aging.

Angiotensin I conversion and coronary constriction by angiotensin II in ischemic and hypoxic isolated rat hearts.

Dose-response curves of angiotensin I (AI, 1.0-1000.0 pmol) and angiotensin II (AII, 1.25-1250.00 pmol) were obtained in isolated rat hearts subjected to control conditions, mild hypoxia (PO2 = 145 mm Hg), reoxygenation, ischemic (perfusion pressure = 35 mm Hg) and reperfusion. Both AI and AII caused dose-dependent coronary flow (CF) of 26 +/- 3 and 27 +/- 2%, respectively. The effects of both AI and AII were substantially attenuated during hypoxia, but were fully restored upon reoxygenation. During ischemia, the effect of AII was unaltered while the effect of AI was enhanced compared to the control (P less than 0.05). This enhancement was reversible on reperfusion. Cardiac conversion of AI, calculated from ED50 values for AI and AII, was significantly increased during ischemia (P less than 0.05). Infusion of saralasin (0.5-5.0 micrograms/min) did not increase CF in any of the groups. We conclude that (1) the coronary vasoconstrictive effect of AII is preserved in ischemia but attenuated in hypoxia and (2) cardiac conversion of AI to AII is enhanced in hearts injured by ischemia.

Effects of endothelin-1 in the isolated heart under ischemic and cardioplegic conditions.

We examined the effects of the vasoconstrictor peptide endothelin-1 in isolated hearts under ischemic and cardioplegic conditions. Isolated isovolumic rat hearts were perfused with Krebs-Henseleit buffer at constant pressure. Cumulative dose-response curves were obtained for endothelin-1 boluses of 0.04-400 pmol in four groups of hearts. Coronary flow decreased with increasing dosages and was almost abolished at 400 pmol in control hearts perfused at a constant pressure of 100 mm Hg. In hearts made ischemic by reducing coronary perfusion pressure to 35 mm Hg, thus reducing coronary flow by 76%, the constrictor effect of endothelin-1 was well preserved. The endothelin-1 dose-response curve was unaltered when hearts were perfused with buffer containing 30 mM KCl to abolish mechanical activity without reducing extracellular Ca2+ concentration. A fourth group of hearts was perfused with Ca2(+)-free buffer, thus eliminating the source of extracellular Ca2+ as well as mechanical activity. In this group, the constrictor response to endothelin-1 was largely, but not completely, abolished, with a maximal constrictor effect of only 19% as opposed to 87% in control hearts. We conclude that in isolated rat heart endothelin-1 is a potent coronary constrictor under ischemic perfusion conditions and that absence of mechanical activity does not affect the action of endothelin-1, for which the presence of extracellular Ca2+ is essential. The small residual constrictor response with Ca2(+)-free perfusion is probably due to release of Ca2+ from intracellular stores.

Effects of endothelin-1 in isolated perfused rat heart.

We examined the effects of the vasoconstrictor peptide endothelin-1 in the isolated heart and defined interactions of endothelin-1 with other hormone systems. Isolated isovolumic rat hearts were perfused with Krebs-Henseleit buffer at constant pressure. First, the effect of a single bolus of endothelin-1 (4-400 pmol) was followed for 90 min. The effect of high dosages (40 and 400 pmol) of endothelin-1 on coronary flow was biphasic, with an early vasodilator and a late vasoconstrictor component that was irreversible. Second, cumulative dose-response curves were obtained for endothelin-1 boluses of 0.04-400 pmol. Coronary flow declined with increasing dosages and was almost abolished at 400 pmol. Neither alpha- nor beta-blocking agents (phentolamine and propranolol) nor the Ca2(+)-channel blocker nifedipine altered the effects of endothelin-1, but prostaglandin synthesis inhibition by indomethacin significantly augmented vasoconstriction by endothelin-1. Angiotensin-converting enzyme (ACE) inhibition by captopril antagonized endothelin-1-dependent vasoconstriction to a small extent at 400 pmol. Coronary constriction due to endothelin-1 could not be reversed by nitroglycerin. We conclude that in isolated rat heart endothelin-1 causes marked and long-lasting coronary constriction. The effect is not influenced by sympathetic and Ca2(+)-channel blockade, is enhanced by prostaglandin synthesis inhibition, and is reduced by ACE inhibition.