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H Schmidt

Publications and source records attributed to H Schmidt.

At least 397 records · Page 22Linked to original sources

Influence of lidocaine on endotoxin-induced leukocyte-endothelial cell adhesion and macromolecular leakage in vivo.

BACKGROUND: Endotoxin activates leukocyte-endothelial cell adhesion, vascular leakage, and changes in vascular micro-hemodynamics. The aim of this study was to determine whether lidocaine, which inhibits the activation of leukocytes, could attenuate microcirculatory disturbances during endotoxemia. METHODS: Thirty anesthetized male rats were randomly assigned to receive one of three treatments (n = 10 for each group): infusion of saline (control group), infusion of Escherichia coli endotoxin (LPS group: 2 mg x kg(-1) x h(-1) lipopolysaccharides) without lidocaine treatment, or infusion of endotoxin with lidocaine pretreatment 30 min before baseline measurements (lidocaine group: intravenous bolus of 2 mg/kg and continuous infusion of 2 mg x kg(-1) x h(-1)). Leukocyte adherence, erythrocyte velocity (V(RBC), and vessel diameters (Dv) were determined at baseline and at 60 and 120 min in mesenteric postcapillary venules using in vivo videomicroscopy. Macromolecular leakage was determined by measuring the extravasation of fluorescence-labeled albumin. Venular wall shear rate (tau) was calculated according to the equation tau = 8 x V(RBC) x Dv(-1). RESULTS: Lidocaine significantly attenuated the increase of leukocyte adherence during endotoxemia. There were no significant differences of tau within or between the groups. Macromolecular leakage exhibited the greatest increase in the LPS group. In the lidocaine group, it was significantly decreased but still increased compared with the control group. CONCLUSIONS: These results show that lidocaine attenuates endotoxin-induced alterations in leukocyte-endothelial cell adhesion and macromolecular leakage, which suggests that lidocaine may have a therapeutic role in preventing endothelial damage in sepsis.

Anesthetics, Local↗

N-acetylcysteine attenuates endotoxin-induced leukocyte-endothelial cell adhesion and macromolecular leakage in vivo.

OBJECTIVE: To determine the influence of N-acetylcysteine on endotoxin-induced leukocyte-endothelial cell adhesion, vascular leakage, and venular microhemodynamics. DESIGN: Randomized, blinded, controlled trial. SETTING: Experimental laboratory. SUBJECTS: Thirty male Wistar rats. INTERVENTIONS: After pretreatment with N-acetylcysteine (150 mg/kg; n = 40; group A) or 0.9% saline solution (n = 10; group B) animals were given an intravenous infusion of endotoxin (Escherichia coli lipopolysaccharide 026:B6; 2 mg/kg/hr) over 120 mins. Animals in the control group (n = 10; group C) received a volume-equivalent infusion of 0.9% saline solution. MEASUREMENTS AND MAIN RESULTS: Leukocyte adherence, red cell velocity (VRBC), vessel diameters, venular wall shear rate, and macromolecular leakage were determined in mesenteric postcapillary venules using in vivo videomicroscopy at baseline and at 30, 50, 90, and 120 mins after the start of the endotoxin challenge. Endotoxin exposure induced a marked increase in adherent leukocytes (group B: baseline, 391 +/- 24 cells/mm2; 120 mins, 1268 +/- 131 cells/mm2; p < .01). N-acetylcysteine pretreatment attenuated the adherence of leukocytes during endotoxemia (baseline, 366 +/- 28 cells/mm2; 120 mins, 636 +/- 49 cells/mm2; p < .01 vs. baseline; p < .01 vs. group B). Leukocyte adherence in control animals (group C) did not increase significantly. Administration of N-acetylcysteine did not influence the decrease in VRBC observed during endotoxemia. In group B1 VRBC decreased during the infusion of endotoxin from 2.0 +/- 0.2 mm/sec at baseline to 1.1 +/- 0.2 mm/ sec after 120 mins (p < .01 vs. baseline; p < .05 vs. group C), and in group A from 2.2 +/- 0.2 mm/sec to 1.1 +/- 0.1 mm/sec after 120 mins (p < .01 vs. baseline; p < .05 vs. group C). In group C, VRBC remained unchanged (baseline, 1.7 +/- 0.2 mm/sec; at 120 mins, 1.5 +/- 0.2 mm/sec). The venular diameters remained unchanged in all groups during the entire study period. After 120 mins, the venular wall shear rate decreased from 502 +/- 62 secs-1 at baseline to 272 +/- 46 sec-1 in group B (p < .01), and from 563 +/- 45 secs-1 at baseline to 283 +/- 31 secs-1 in group A (p < .01). No differences in venular wall shear rate were observed between these groups. In group C, the venular wall shear rate remained unchanged (baseline, 457 +/- 54 secs-1; at 120 mins, 409 +/- 51 secs-1). Macromolecular leakage, expressed as perivenular/intravenular fluorescence intensity after injection of fluorescence-labeled albumin, increased from 0.29 +/- 0.03 to 0.58 +/- 0.03 (p < .01) during the infusion of endotoxin in group B. In contrast, pretreatment with N-acetylcysteine diminished the extravasation of albumin (baseline, 0.27 +/- 0.01; at 120 mins, 0.37 +/- 0.02; p < .01 vs. baseline; p < .01 vs. group B). CONCLUSION: These results demonstrate that N-acetylcysteine attenuates endotoxin-induced alterations in leukocyte-endothelial cell adhesion and macromolecular leakage, suggesting N-acetylcysteine might be therapeutic in the prevention of endothelial damage in sepsis.

Acetylcysteine↗

The art of seeing.

This article, written by a home care nurse from Norway, won the World Health Organization's Balint Prize for the field of health and nursing care in 1996. The author shares a compelling client situation illustrating that home care nurses throughout the world share many attributes, but the main one is caring.

Aged↗

Ciprofloxacin in pediatrics: worldwide clinical experience based on compassionate use--safety report.

BACKGROUND: Quinolone-induced cartilage toxicity has been observed in experimental juvenile animal studies and is species- and dose-specific. Accordingly these findings have led to the contraindication of fluoroquinolones in children. Previous data in 634 adolescents and children treated with compassionate use ciprofloxacin demonstrated low rates of reversible arthralgia and a safety profile similar to that for adult patients. OBJECTIVE: This report describes the safety findings in 1795 children who received 2030 treatment courses of intravenous or oral ciprofloxacin. RESULTS: The average doses of intravenous and oral ciprofloxacin in the study population were 8 and 25 mg/kg/day, respectively. Treatment-associated events were reported in 10.9% of children receiving oral ciprofloxacin compared with 18.9% among intravenous recipients. Overall arthralgia occurred during 31 ciprofloxacin treatment courses (1.5%) and the majority of events were of mild to moderate severity and resolved without intervention. More than 60% of arthralgia episodes were in children with cystic fibrosis. CONCLUSION: The adverse event pattern in children receiving ciprofloxacin in this analysis was similar to that observed in adults. Rates of reversible arthralgia were low and unchanged from previously published surveillance data in children.

Administration, Oral↗

Prognostic relevance of C-terminal Mdm2 detection is enhanced by p53 positivity in soft tissue sarcomas.

We examined the clinical value of immunohistochemical (IHC) Mdm2 detection by an N-terminal (IF2) and a C-terminal (19E3) binding monoclonal antibody (Ab) in soft tissue sarcomas (STSs) with regard to the p53 status. Therefore, we investigated a cohort of 198 patients with STSs of six entities with known p53 IHC by using a multivariate Cox regression model to determine the prognostic value of Mdm2 staining. Only positivity with the 19E3 Ab correlated multivariately significantly with survival (RR = 2.32, p = 0.0035). We stratified the C-terminal Mdm2 staining (19E3) according to p53 IHC (DO-1) and found patients could be divided into three groups with an increasing risk: (a) patients with Mdm2 (19E3)-negative as well as p53 (DO-1)-negative tumors, (b) patients with tumors that were either Mdm2 (19E3) or p53 (DO-1) positive, and (c) patients with tumors that were Mdm2 (19E3) as well as p53 (DO-1) positive. Positive staining for both Mdm2 and p53 meant a very poor prognosis with a relative risk of 4.63 (p = 0.00001). This points to the possibility that--in addition to the p53-dependent pathway--Mdm2 could have an effect through a p53-independent pathway. Thus, our results indicate that C-terminal Mdm2 staining (19E3) constitutes an independent prognostic marker in STS.

Adolescent↗

Impact of autotransfusion after coronary artery bypass grafting on oxygen transport.

BACKGROUND: Autotransfusion of shed mediastinal blood after coronary artery bypass grafting (CABG) has been shown to reduce the requirement for allogeneic blood. We have previously demonstrated in non-randomized studies that the oxygen capacity of shed mediastinal blood is similar to the patient's circulating blood and better than stored allogeneic blood. Therefore, we wanted to examine the influence of autotransfusion of shed mediastinal blood on oxygen transport capacity in patients undergoing CABG. METHODS: A prospective, randomized, controlled study involving 120 patients having elective, uncomplicated CABG was performed. The autotransfusion group received transfusion of shed mediastinal blood for 18 h. Both groups received allogeneic red cells if their hemoglobin concentration decreased below 5 mmol/L. Red blood cell 2,3-diphosphoglycerate (2,3-DPG) was measured preoperatively and at intervals up to the hospital discharged. Hemodynamic measurements as well as blood gas and hemoglobin measurements from samples of arterial and mixed venous blood were used for calculation of oxygen transport capacity. RESULTS: During the autotransfusion period only 2 patients (4%) in the autotransfusion group required allogeneic blood compared to 11 patients (20%) in the control group. The 2,3-DPG levels in the autotransfusion group were unchanged before and after autotransfusion (4.4 vs. 4.3 mumol/ml erythrocyte). In the control group, 2,3-DPG levels decreased from 4.3 to 3.9 mumol/ml erythrocyte during the same period. There were no differences in the other measured parameters for oxygen transport capacity between the groups. CONCLUSION: Autotransfusion of shed mediastinal blood conserves the 2,3-DPG level of the red blood cells, while transfusion of stored blood leads to a decrease in 2,3-DPG levels. Autotransfusion had no effect on hemodynamic parameters, oxygen delivery or oxygen extraction.

2,3-Diphosphoglycerate↗

Leukemic cells within skin lesions of psoriasis in a patient with acute myelogenous leukemia.

We report on an 81-year-old man with acute myelo-monocytic leukemia (FAB M4) and a long-standing history of psoriasis. Biopsy of psoriatic plaques revealed the coexistence of characteristic histopathologic aspects of psoriasis together with an infiltrate of blasts with features of myelo-monocytes, suggestive of a specific leukemic infiltrate within plaques of psoriasis. Immunohistologic stainings showed positivity of blasts for LN2 (CD74), MT1 (CD43), and lysozyme, consistent with a myeloid lineage of these cells. To the best of our knowledge, this is the first report on the association of psoriasis with myelogenous leukemia. The presence of leukemic cells within psoriatic skin plaques may be explained by non-specific recruitment of recirculating malignant cells to the skin. Alternatively, as psoriasis is an inflammatory disease involving granulocytes among other cell types, it may be hypothesized that leukemic cells retain to some extent their capability to respond to physiologic stimuli and enter the skin in response to specific chemotactic factors.

Aged↗

Apolipoprotein E polymorphism and silent microangiopathy-related cerebral damage. Results of the Austrian Stroke Prevention Study.

BACKGROUND AND PURPOSE: Microangiopathy-related cerebral damage (MARCD) includes white matter abnormalities and lacunar infarctions and represents a common MRI observation in subjects above 50 years of age. The risk factors of such brain abnormalities are not fully determined. The goal of this study was to determine whether the genetic heterogeneity of apolipoprotein E (apoE) contributes to the occurrence of MARCD. METHODS: Brain MRI (1.5 T) was performed in 280 individuals (ages 50 to 75 years) without neuropsychiatric disease randomly selected from the official register of residents of the city of Graz, Austria. All study participants underwent apoE genotyping, carotid Doppler sonography, electrocardiography, echocardiography, and a complete blood chemistry panel. MARCD was defined as evidence of early confluent and confluent white matter hyperintensities or lacunes. Carotid atherosclerosis was graded on a five-point scale ranging from not present (0) to complete occlusion (5). RESULTS: MARCD occurred in 61 individuals (21%). The distribution of apoE genotypes differed significantly between subjects with and without MARCD (P = .036). Subjects with such findings more commonly had the epsilon 2/epsilon 3 genotype (24.6% versus 10%) at similar frequencies of genotypes containing the epsilon 4 allele. The epsilon 2/epsilon 3 genotype was associated with lower levels of total cholesterol (P = .0009), LDL cholesterol (P = .00001), and apolipoprotein B (P = .00001). Also, there was a nonsignificant trend toward less cardiac disease. Other major vascular risk factors and carotid abnormalities were similar among the various genotypes. Multiple logistic regression analysis created a model of significant MARCD predictors, including age (odds ratio [OR], 1.1 per year), hypertension (OR, 3.4), and the apoE epsilon 2/epsilon 3 genotype (OR, 3.0). CONCLUSIONS: These data suggest an association between the apoE epsilon 2/epsilon 3 genotype and MARCD despite favorable effects on the lipid profile and cardiac disease.

Aged↗

Functioning thoracic paraganglioma: association with Von Hippel-Lindau syndrome.

Functioning thoracic paraganglioma (pheochromocytoma) is unusual and therefore suggestive of a pathogenesis distinct from that of sporadic adrenal pheochromocytoma. To determine whether the pheochromocytoma-associated syndromes Von Hippel-Lindau disease (VHL) and multiple endocrine neoplasia type 2 (MEN 2) play a role in the development of thoracic functioning paragangliomas, germline DNA from five unselected patients with this rare tumor was analyzed for mutations in the genes that predispose to VHL and MEN 2. Genetic investigations and further clinical data revealed that three had VHL, with two different germline mutations of the vhl gene, but no individual was affected by MEN 2. Two of the three patients with VHL did not show any additional VHL-associated lesions. This result suggests that VHL should be considered in the differential diagnosis of thoracic pheochromocytoma, as such a diagnosis carries further important implications for the patient and family. Conversely, in patients suspected of a catecholamine-secreting tumor and known VHL, thoracic localization should be considered if an adrenal pheochromocytoma cannot be detected.

Adolescent↗

Psychiatric disorders in adult patients with early-treated phenylketonuria.

OBJECTIVE: To determine psychiatric disorders in patients with phenylketonuria (PKU) and to test whether biochemical control, intellectual functioning, white matter abnormalities visible on magnetic resonance imaging (MRI), and/or style of parenting influence psychopathology. DESIGN AND SUBJECTS: This cross-sectional study consisted of 35 PKU patients 17 to 33 years of age (mean: 22.2). From a total of 67 patients, 3 patients were selected because of other causes of possible brain damage. Then 35 patients were randomly drawn with comparison with a control sample (n = 181) from an epidemiologic study. METHODS: We used a standardized, highly structured, face-to-face interview; intelligence quotient (IQ) test; cranial MRI (n = 26); and monitoring of plasma phenylalanine. RESULTS: The overall rate of psychiatric disorders was 25.7% in PKU patients and 16.1% in controls. This difference was not statistically significant. The pattern of psychiatric disturbances was different for PKU patients and controls (Fisher's exact test): in PKU patients, externalizing disorders were reduced (PKU: not present, controls: 7.8%), whereas internalizing disorders (PKU: 25.7%, controls: 8.3%) were increased. International Classification of Diseases, version 10, diagnoses were predominantly those of the depressive category and more frequent in women (8 of 18 females and 1 of 17 males). A correlation between IQ and both biochemical control up to 12 years of age and school education of parents was confirmed. No correlation was found between the severity or pattern of psychiatric disturbances and school education of parents, biochemical control, IQ, or the extension of MRI-visible, white matter abnormalities. It was found that a restrictive controlling style of parenting is a risk factor for the development of psychiatric symptoms. CONCLUSIONS: Our results support a psychological perspective for the development of psychiatric symptoms in PKU. Thus, optimizing medical treatment necessary to prevent brain damage should be accompanied by psychiatric monitoring and psychological support for the families.

Adolescent↗

[Prevalence and risk factors in the population of Graz (Austrian Stroke Prevention Study)].

The Austrian Stroke Prevention Study recruited 1960 randomly selected subjects aged 50 to 75 years during a 3-year period of enrollment. The response rate of the study was 32.4%. A telephone interview with 200 randomly selected non-responders yielded no differences to responders regarding the frequency of major vascular risk factors known to the subjects. Besides demographics, the study assessed arterial hypertension, diabetes mellitus, cardiac disease, smoking, a complete lipid status including the apolipoprotein-E genotype, serum fibrinogen and anticardiolipin antibodies as well as various natural antioxidants such as vitamins A, C, E and beta-carotene. Arterial hypertension, diabetes mellitus, cardiac disease and hypercholesterolemia > 200 mg/dl were strikingly common and occurred in 38%, 7.6%, 32% and 76%, respectively. Suboptimal plasma concentrations of vitamin A, E, and beta-carotene were noted in 77.2%, 56.1% and in 53.2% of study participants. The rate of treatment of major risk factors known to the subjects prior to study entry were 60.3% and 70% for arterial hypertension and diabetes mellitus, but only 37.1% and 6.3% for cardiac disease and hypercholesterolemia > 250 mg/dl. Diet was commonly used to treat diabetes but was almost neglected in the treatment of other vascular risk factors. These data provide an orientation on the prevalence of risk factors and the use of primary preventive measures for stroke treatment in our community.

Adult↗

[The heart in infection and MODS (multiple organ dysfunction syndrome)].

Dysfunctioning of the heart forms part of the multiple organ dysfunction syndrome (MODS) in sepsis and SIRS. This acute septic cardiomyopathy is often underestimated in degree and relevance, although yet in fact 10% of all sepsis fatalities are due to intractable heart failure. This potentially reversible cardiomyopathy is characterized by a considerable pump failure, is not primarily ischemic, coronary blood flow being normal or even enhanced; left and right ventricle are enlarged as a consequence of an increased ventricular compliance. Damage of the heart can further be aggravated in case of an additional right ventricular impairment due to pulmonary hypertension in ARDS. SIRS-cardiomyopathy in non-infectious MODS has common traits with acute septic cardiomyopathy. The pathogenesis of heart disease in sepsis and SIRS is multifactorial, the endotoxin/TNF-alpha/NO/cGMP-cascade representing a main negative inotropic axis. Therapy of acute septic cardiomyopathy and SIRS-cardiomyopathy at present still is mainly symptomatic (volume substitution, inotropic/vasoactive agents), causal therapeutic principles are, however, put to test in the context of a comprehensive concept of causal sepsis treatment.

Cardiomyopathies↗

[Problems in nasal CPAP management of the obstructive apnea patient--when is a tracheotomy indicated? A case report].

The use of nCPAP-ventilation has changed the rare indication for tracheotomy in patients with severe sleep apnoe syndrome. Only in cases where obstructive nasal and epipharyngeal processes are not resectable tracheotomy can be necessary. A case report shows one indication for such a surgical intervention. Increasing nasal obstruction usually can be treated successfully by operation.

Carcinoma↗

Anti-endothelial cell antibodies in Takayasu arteritis.

BACKGROUND: Although a specific etiology for Takayasu arteritis has not been found, the bulk of evidence favors an autoimmune mechanism. We examined the sera of 19 patients with Takayasu arteritis for antineutrophil cytoplasmic antibodies (ANCA), antinuclear antibodies (ANA), anti-DNA antibodies, antibodies to extractable nuclear antigens (ENA), anti-Ro anti-bodies, anticardiolipin antibodies, circulating immune complexes, and anti-endothelial cell antibodies (AECA). METHODS AND RESULTS: We used enzyme-linked immunoassays, immunofluorescence, counterimmunoelectrophoresis, fluorescent-activated cell sorter (FACS) analysis, and confocal microscopy. We found that although no patient had positive ANCA, ANA, anti-DNA antibodies, ENA antibodies, anti-Ro antibodies, or anticardiolipin antibodies, 18 of the 19 patients had AECA. The AECA titers of the patients were 2561 +/- 1458 compared with 126 +/- 15 arbitrary units in a normal group of control subjects (P < .001). To verify the specificity of AECA, we performed cytofluorimetry on human endothelial cells with the sera from patients and control subjects. Two entirely separate patterns of fluorescence intensity were identified. We next performed immunocytochemistry and confocal microscopy with human endothelial cells subjected to patients' sera and to sera from normal subjects. The cells subjected to sera from patients with Takayasu arteritis demonstrated specific immunofluorescent staining of their plasma membrane and cytosol. CONCLUSIONS: AECA are frequently present in patients with Takayasu arteritis. They may play a role in the pathogenesis. Furthermore, they may be useful as an additional diagnostic tool.

Adolescent↗

Pore-forming properties of the plasmid-encoded hemolysin of enterohemorrhagic Escherichia coli O157:H7.

Lipid bilayer experiments were performed with the plasmid-encoded hemolysin of enterohemorrhagic Escherichia coli (EHEC) O157:H7 strain EDL933. EHEC-hemolysin caused the formation of transient ion-permeable channels by integration in lipid bilayer membranes composed of asolectin, dioleoylglycerophosphoethanolamine and phosphoserine but not of diphytanoylglycerophosphocholine. Channel formation showed the same characteristics when culture supernatants of E. coli strains EDL 933 or HB101/pEO40, precipitated or purified EHEC-hemolysin were used for these experiments. The EHEC-hemolysin channels had two different states at small transmembrane potential (20 mV): a prestate that represented the first step of channel formation (single-channel conductance 40 pS in 0.15 M KCl) and an open state (550 pS in 0.15 M KCl at pH 6.0). Experiments with different salts suggested that the EHEC-hemolysin-induced channels were cation-selective at neutral pH. The mobility sequence of the cations within the channels resembles their mobility sequence in the aqueous phase. The single-channel data were consistent with the formation of wide, water-filled channels by the EHEC hemolysin. The single channel conductance was strongly pH dependent and increased over 2.5-fold in the pH range 5-8. The analysis of the single-channel data using the Renkin correction factor suggested that the EHEC-hemolysin formed channels with an average diameter of 2.6 nm. This size could be confirmed by the results of osmotic-protection experiments. Neither sucrose nor raffinose inhibited toxin-dependent hemolysis, whereas hemolysis did not occur in the presence of dextran 4 (molecular mass, 4 kDa). Our results demonstrate that EHEC-hemolysin can be considered to be a highly active repeats-in-toxin (RTX)-toxin with a similar but not identical pore-forming capacity as the chromosomal encoded E. coli alpha-hemolysin.

Electric Conductivity↗

[Decompensated acute gastric dilatation caused by a bulimic attack in anorexia nervosa].

HISTORY AND CLINICAL FINDINGS: Abdominal pain developed after a bulimic binge in a 19-year-old girl with anorexia nervosa. She had unsuccessfully tried to induce vomiting. Physical examination showed no clinical sign of peritonitis, although there was diffuse abdominal tenderness on pressure. INVESTIGATIONS: There was leukopenia (2200 G/l) and a raised serum lactate level (58 mg/dl). No free air was seen on a plain film of the abdomen. Abdominal sonography revealed little free fluid subhepatically. TREATMENT AND COURSE: Acute respiratory impairment during investigations required emergency intubation. As bronchoscopy revealed aspiration a bronchial lavage was performed. Under gastroscopic control gastric emptying was achieved through a large gastric tube. After early improvement the patient developed the full picture of sepsis. Ultrasonography and needle puncture having revealed purulent intraabdominal fluid, a laparotomy was performed, which showed necrosis of the anterior and posterior walls of the stomach with free perforation. The greater curvature was resected. The patient slowly recovered but a relaparotomy for a subphrenic abscess became necessary on the 10th postoperative day. A year later there was free food passage, but the anorexia nervosa was unchanged. CONCLUSION: A bulimic binge can become life-threatening if the stomach does not empty spontaneously. Surgical intervention is required, if the patient's condition does not improve despite gastric emptying.

Adult↗