Biomedical subjects

Matthias Pirlich

Publications and source records attributed to Matthias Pirlich.

21 records · Page 2Linked to original sources

PubMed2002

Increased proteolysis after single-dose exposure with hepatotoxins in HepG2 cells.

Chronic ethanol consumption is associated with increased protein oxidation and decreased proteolysis in the liver. We tested the hypothesis that even single-dose treatment with ethanol or bromotrichloromethane causes increased protein oxidation and a distinct proteolytic response in cultured hepatocytes. HepG2 cells were treated for 30 min with ethanol, H(2)O(2) and bromotrichloromethane at various nontoxic concentrations. Protein degradation was measured in living cells using [35S]-methionine labeling. Protein oxidation, and 20S proteasome activity were measured in cell lysates. Oxidized proteins increased immediately after ethanol, H(2)O(2), and bromotrichloromethane exposure, but a further significant increase 24-h after exposure was observed only following ethanol and bromotrichloromethane treatment. All three reagents caused a significant increase of the overall intracellular proteolysis at rather low concentrations, which could be suppressed by the proteasome inhibitor lactacystin. A decline of proteolysis observed at higher-subtoxic-concentrations was not related to decreased proteasome activity. Preincubation with ketoconazole or 4-methylpyrazole completely prevented the ethanol- and bromotrichloromethane-induced but not the H(2)O(2)-induced protein oxidation and proteolysis, suggesting strongly an enzyme-mediated generation of reactive oxygen species. In conclusion single-dose exposure with ethanol or haloalkanes causes increased protein oxidation followed by an increased proteasome-dependent protein degradation in human liver cells.

Bromotrichloromethane↗

PubMed2002

Loss of body cell mass in Cushing's syndrome: effect of treatment.

Cushing's syndrome (CS) is associated with low fat-free mass, but it is unclear whether hypercortisolism causes a loss of whole body protein. Body composition was studied prospectively in 15 patients with untreated CS (n = 14 pituitary adenoma; n = 1 adrenal adenoma), in 15 nonobese healthy controls, and in 15 weight-matched obese controls by 3 different methods: total body potassium counting (TBP), bioelectrical impedance analysis (BIA), and anthropometry. In 6 patients, body composition was studied before and within 6 months after pituitary surgery. In CS patients and weight-matched controls, body weight and total body fat were significantly higher than in nonobese controls. In CS patients, TBP was 18.4% lower than predicted, whereas in weight-matched controls TBP was 7.1% higher than predicted. As compared with nonobese and weight-matched controls, in CS patients TBP indicated a significant loss of body cell mass (BCM) of -20.2 and -21.1%, respectively. A significantly reduced arm muscle area of -21.3% compared with weight-matched controls also indicated a loss of whole body protein. In CS, however, BIA overestimated BCM when compared with TBP by +18% and agreement between BIA and TBP in the individual patient was poor (limits of agreement plus minus 27.6%), indicating the invalidity of standard BIA equations in this population. Measurements performed before and 6 months after successful pituitary surgery demonstrated a significant loss of body weight (-11%) and body fat (-33%), but BCM and muscle mass remained on a constant low level. In conclusion, this study shows that, in patients with CS, a significantly reduced BCM indicates a true protein loss. The second interesting finding is that in the early recovery after successful treatment of hypercortisolism patients lose body fat without gaining BCM or muscle mass.

Adult↗

PubMedDate not supplied

Is nutritional depletion by Nutritional Risk Index associated with increased length of hospital stay? A population-based study.

BACKGROUND: Malnutrition is common at hospital admission and tends to worsen during hospitalization. This controlled population study aimed to determine if serum albumin or moderate and severe nutritional depletion by Nutritional Risk Index (NRI) at hospital admission are associated with increased length of hospital stay (LOS) (and increased hospital cost) in patients admitted to hospitals in 2 European countries. METHODS: Serum albumin levels and recent weight loss were prospectively determined at hospital admission in Geneva (n = 652) and Berlin (n = 621). Patients were classified as no, mild, moderate or severe risk by NRI. Multiple logistic regressions were used to determine the association between albumin and nutritional risk category and LOS. RESULTS: Patients (24%) were at moderate or severe nutritional risk by NRI. Nutritional risk by NRI, adjusted for age, was associated with LOS of 11 days (moderate: odds ratio [OR] 1.9, 95% confidence interval [CI] 1.4 to 2.7, p < .005; severe: OR 2.9, 95% CI 1.6 to 5.3, p < .005). Serum albumin was also significantly associated with increased LOS (p < .001). CONCLUSIONS: The prevalence of nutritional depletion assessed by NRI and albumin was increased with longer LOS. Albumin alone underestimated nutritional risk. Severe nutritional depletion by NRI was significantly associated with LOS > or = 11 days in Geneva and Berlin patients. Nutrition screening should take place at hospital admission to determine nutritional risk and risk for longer LOS.

Aged↗