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H Schomerus

Publications and source records attributed to H Schomerus.

At least 19 recordsLinked to original sources
PubMed2001

Counting statistics of photons produced by electronic shot noise.

A theory is presented for the photodetection statistics of radiation produced by current fluctuations in a phase-coherent conductor. Deviations are found from the Poisson statistics that would result from a classical current. For detection in a narrow frequency interval delta omega, the photocount distribution has the negative-binomial form of blackbody radiation if e delta omega is less than the mean current I in the conductor. When electronic localization sets in, I drops below e delta omega and a different type of super-Poissonian photon statistics results.

Journal Article↗
PubMed2000

Search for two-scale localization in disordered wires in a magnetic field

A recent paper [A. V. Kolesnikov and K. B. Efetov, Phys. Rev. Lett. 83, 3689 (1999)] predicts a two-scale behavior of wave function decay in disordered wires in the crossover regime from preserved to broken time-reversal symmetry. We have tested this prediction by a transmission approach, relying on the Borland conjecture that relates the decay length of the transmittance to the decay length of the wave functions. Our numerical simulations show no indication of two-scale behavior.

Journal Article↗
PubMed2000

Hepatic encephalopathy in liver cirrhosis: pathogenesis, diagnosis and management.

The pathogenesis of hepatic encephalopathy (HE) is unknown. Many theories have been proposed. Most established therapies are based on such theories but since no theory has have ever been proved, therapies have to be considered empiric. The spectrum of HE ranges from minimal cerebral functional deficits, which can only be found by sensitive psychometric tests, to coma with signs of decerebration. HE has arbitrarily been divided into stages. A number of precipitating factors are known and the first line of therapy should always be the elimination of these factors. The differential diagnosis includes all states of impaired consciousness and deficits in cerebral function in patients with chronic liver disease, and clinical and biochemical tests to differentiate are indicated. The therapeutic options for HE include: protein restriction only for a limited time in comatous patients; nonabsorbable antibiotics (aminoglycosides), which because of adverse effects are also limited to higher grades of HE: intestinal cleansing which is applicable in all degrees of HE; lactulose, branched chain aminoacids and ornithin aspartate which have been proven to be effective and can be applied long term in patients with lower grades of HE.

Anti-Bacterial Agents↗
PubMed1998

Neuropsychological aspects of portal-systemic encephalopathy.

An extensive psychometric test program was performed in 96 patients with proven liver cirrhosis and clinical signs of portal hypertension as well as in 20 patients with alcoholic pancreatitis, in 19 patients without cirrhosis but with alcoholic cerebral atrophy and in 163 normal controls. The study population comprised six groups of subjects as follows: Group 1. 27 patients with non-alcoholic cirrhosis and normal EEG pattern. Group 2. 48 patients with alcoholic cirrhosis and normal EEG pattern. Group 3. 21 patients with cirrhosis and minimal EEG changes. Group 4. 20 patients with alcoholic pancreatitis. Group 5. 19 patients without cirrhosis but with alcoholic cerebral atrophy. Group 6. 163 normal controls. A one way analysis of variances comparing asymptomatic patients (group 1, 2 and 4) with controls (group 6) revealed no significant differences between patients with alcoholic and non-alcoholic cirrhosis, both cirrhotic groups scoring significantly lower than patients with alcoholic pancreatitis and normal controls, who did not differ significantly. Comparing symptomatic patients (group 3 and 5) with normal controls both patient groups scored significantly lower than controls, the cirrhotic group (group 3) scoring significantly lower than patients with alcoholic cerebral atrophy. A two way analysis of variances revealed that in clinically asymptomatic patients cerebral functional defects revealed by psychometry are only due to cirrhosis and that in patients with clinical evidence of cerebral impairment the factors alcohol and cirrhosis are additive - not synergistic. A multiple group stepwise discriminant analysis revealed that tests evaluating psychomotor functions contributed most to the discrimination. Especially "line tracing " proved to be most sensitive and most specific followed by dexterity, steadiness, aiming, digit symbols in sensitivity and by reaction time, steadiness and dexterity in specificity. A test program for clinical use is proposed.

Alcohol Drinking↗
PubMed1993

Prevalence of latent portasystemic encephalopathy in an unselected population of patients with liver cirrhosis in general practice.

To evaluate the prevalence of latent PSE in unselected ambulatory patients with liver cirrhosis practicing physicians were asked to perform two non instrumental psychometric tests (number connection test and line tracing test) on patients with clinical signs of liver cirrhosis and portal hypertension. Tests were repeated after 8 weeks of treatment with Lactulose in those patients considered to have latent PSE at the initial evaluation. 296 physicians tested a total of 783 patients, 771 of these could be evaluated. 551 patients (71.5%) were considered to have latent PSE. There was a significant correlation between psychometric test results and biochemical parameters related to liver function. Repeat testing after 8 weeks treatment with Lactulose revealed definite improvement of psychometric test results in 88% of the patients. At the final evaluation only about 30% of the patients fulfilled the criteria of latent PSE. There was a statistically significant albeit weak correlation between changes in biochemical parameters and psychometric improvement. Psychometric testing with simple non instrumental tests proved to be practicable in the office setting.

Adult↗
PubMed1990

Evaluation of the Crohn's Disease Activity Index (CDAI) and the Dutch Index for severity and activity of Crohn's disease. An analysis of the data from the European Cooperative Crohn's Disease Study.

In the European Cooperative Crohn's Disease Study a general documentation of clinical and laboratory data was made at the entry into the study in 452 patients. These patients were in different states of their disease from quiescent to very active. In all patients the Crohn's Disease Activity Index of Best (CDAI) and the Dutch Index of van Hees was calculated. Three gastroenterologists did a global clinical rating and a separate laboratory rating without knowledge of the indices. The ratings were then correlated with the indices in the individual patients. The clinical rating correlated well with the CDAI (r = 0.88) and less with the Dutch Index (r = 0.672). On the other hand the laboratory rating showed a better correlation with the Dutch Index (r = 0.742) than with the CDAI (r = 0.573). This demonstrates that the CDAI preferably is an estimate of the clinical severity of the disease and not of the activity of inflammation. Vice versa the Dutch Index is mainly reflecting the activity of the inflammatory process.

Colitis↗
PubMed1987

[The disease picture of hepatic encephalopathy].

Hepatic encephalopathy implies disturbances of consciousness, intellectual function, behavior and neuromuscular function in the course of diseases of the liver. By employing psychometric and neurophysiologic methods, functional disturbances can be demonstrated well before clinical manifestation of encephalopathy. This latent form of encephalopathy is especially disturbing for patients doing manual work. Treatment should be started during this early phase of the disease.

Brain↗
PubMed1986

[Branched-chain amino acids in the treatment of latent porto-systemic encephalopathy. A placebo-controlled double-blind cross-over study].

In a doubleblind cross-over placebo-controlled trial the efficiency of oral treatment with branched chain amino acids was investigated in 22 inpatients with liver cirrhosis. In all patients evidence of latent (subclinical) portalsystemic encephalopathy was obtained by using an extensive psychometric test programme. Patients received a defined diet of 35 cal/kg/day containing 1 g of protein. In addition, branched chain amino acids or casein in a dosage of 0.25 g/kg/day was administered in a cross-over fashion, each for 1 week. Semiquantitative nitrogen balance increased during both treatments, with a tendency towards a larger increase during branched chain amino acid treatment. At the same time ammonia concentration tended to decrease during branched chain amino acid treatment. Taking into account the cross-over design, significant improvements attributable to branched chain amino acid treatment could be demonstrated in psychomotor functions (line tracing, tapping, steadiness, auditory reaction time), attention (digit table), and practical intelligence (digit symbol, number connection test).

Administration, Oral↗
PubMed1985

Serum inhibitory factors (SIF) are of prognostic value in acute viral hepatitis.

Serum inhibitory factors (SIF) were analysed in relation to the natural course of acute viral hepatitis in 81 patients followed over a period of 1 year. 63 patients recovered completely (group 1), and 18 had a protracted course of hepatitis (group 2) as shown by persistent transaminase activity 6 months after onset. 11 patients in group 2 still had signs of liver disease after 1 year. A gradual fall of SIF activity (in 47 patients) heralded resolving hepatitis, whereas persistence of SIF (in 8 patients) correlated with inflammatory activity and failure of hepatitis B viral antigen elimination. Absence of SIF activity was associated with either an uncomplicated or a chronic course of hepatitis in 23 and 3 patients, respectively. Repeated determination of SIF may help to predict the final outcome of hepatitis. Both excessive and failure of SIF production may result in the development of chronic liver disease.

Acute Disease↗
PubMed1985

Branched chain amino acids in the treatment of latent portosystemic encephalopathy. A double-blind placebo-controlled crossover study.

Branched chain amino acids have been recommended for the treatment of portosystemic encephalopathy based on the false neurotransmitter hypothesis. This hypothesis implies that by correction of the deranged amino acid pattern in the blood of cirrhotics, false neurotransmission and then portosystemic encephalopathy is improved. We conducted a double-blind crossover placebo-controlled trial in 22 inpatients with liver cirrhosis and obtained evidence of latent (subclinical) portosystemic encephalopathy using an extensive psychometric test program. Patients received a defined diet of 35 cal/kg X day containing 1 g of protein. In addition, branched chain amino acids or casein in a dosage of 0.25 g/kg X day was administered in a crossover fashion, each for 1 wk. Semiquantitative nitrogen balance increased during both treatments, with a tendency of a larger increase during branched chain amino acid treatment. At the same time ammonia concentration tended to decrease during branched chain amino acid treatment. Taking into account the crossover design, significant improvements attributable to branched chain amino acid treatment could be demonstrated in psychomotor functions (line tracing, tapping, steadiness, auditory reaction time), attention (digit table), and practical intelligence (digit symbol, number connection test).

Adult↗
PubMed1985

[Severe liver damage as a drug-allergy reaction to cefoperazone].

A 20 year old man was treated with cefoperazone for 25 days because of a local infection after an open fracture complicated by pseudarthrosis. Severe liver damage was noted on 25th day of cefoperazone treatment. There was extreme elevation of transaminases and alkaline phosphatasis as well as jaundice and prolonged prothrombin time. Upper GI bleeding, fever and acute renal failure developed. All symptoms disappeared after cessation of cefoperazone. A causal relationship between the drug and liver damage seems likely because of a positive lymphocyte stimulation test, the time relation between cefoperazone therapy and change in liver function as well as the development of eosinophilia. Other causes of liver damage could be excluded. The pathogenesis of liver damage, upper GI bleeding and acute renal failure is discussed.

Adult↗