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E Bauer

Publications and source records attributed to E Bauer.

At least 55 records · Page 3Linked to original sources
PubMed1998

Imaging of adenoviral-directed herpes simplex virus type 1 thymidine kinase reporter gene expression in mice with radiolabeled ganciclovir.

UNLABELLED: We are developing procedures to repeatedly and noninvasively image the expression of transplanted reporter genes in living animals and in patients, using PET. We have investigated the use of the Herpes Simplex Virus type 1 thymidine kinase gene (HSV1-tk) as a reporter gene and [8-14C]-ganciclovir as a reporter probe. HSV1-tk, when expressed, leads to phosphorylation of [8-14C]-ganciclovir. As a result, specific accumulation of phosphorylated [8-14C]-ganciclovir should occur almost exclusively in tissues expressing the HSV1-tk gene. METHODS: An adenoviral vector was constructed carrying the HSV1-tk gene along with a control vector. C6 rat glioma cells were infected with either viral vector and uptake of [8-3H]-ganciclovir was determined. In addition, 12 mice were injected with varying levels of either viral vector. Adenovirus administration in mice leads primarily to liver infection. Forty-eight hours later the mice were injected with [8-14C]-ganciclovir, and 1 hr later the mice were sacrificed and biodistribution studies performed. Digital whole-body autoradiography also was performed on separate animals. HSV1-tk expression was assayed, using both normalized HSV1-tk mRNA levels and relative HSV1-TK enzyme levels, in both the cell culture and murine studies. RESULTS: Cell culture, murine tissue biodistribution and murine in vivo digital whole-body autoradiography all demonstrate the feasibility of HSV1-tk as a reporter gene and [8-14C]-ganciclovir as an imaging reporter probe. A good correlation (r2 = 0.86) between the [8-14C]-ganciclovir percent injected dose per gram tissue from HSV1-tk positive tissues and HSV1-TK enzyme levels in vivo was found. An initial study in mice with [8-18F]-fluoroganciclovir and microPET imaging supports further investigation of [8-18F]-fluoroganciclovir as a PET reporter probe for imaging HSV1-tk gene expression. CONCLUSION: These results demonstrate the feasibility of using [8-14C]-ganciclovir as a reporter probe for the HSV1-tk reporter gene, using an in vivo adenoviral mediated gene delivery system in a murine model. The results form the foundation for further investigation of [8-18F]-fluoroganciclovir for noninvasive and repeated imaging of gene expression with PET.

Adenoviridae↗
PubMed1997

Cyclosporine as maintenance therapy in patients with severe psoriasis.

BACKGROUND: Low-dose cyclosporine therapy for severe plaque psoriasis is effective. Most side effects can be controlled by patient monitoring, with appropriate dose adjustment or pharmacologic intervention, or both, if indicated. Prevention or reversibility of laboratory and chemical abnormalities may be achieved by discontinuation of therapy after the induction of clearing. However, relapse occurs rapidly on discontinuation. Maintenance therapy with cyclosporine after induction has not been fully evaluated. OBJECTIVE: Our purpose was to compare a regimen of 3.0 mg/kg per day of oral cyclosporine with placebo in maintaining remission or improvement in patients with psoriasis. METHODS: After a 16-week unblinded induction phase in which 181 patients received cyclosporine, 5.0 mg/kg per day (an increase up to 6.0 mg/kg per day and a decrease to 3.0 mg/kg per day were allowed, if required, to achieve efficacy or tolerability, respectively), those patients showing a 70% decrease or more in involved body surface area (BSA) entered the 24-week maintenance phase and were randomly assigned to either placebo, cyclosporine, 1.5 mg/kg per day, or cyclosporine, 3.0 mg/kg per day. Patients were considered to have had a relapse when BSA returned to 50% or more of the prestudy baseline value. Clinical efficacy, adverse effects, and laboratory values were monitored regularly throughout both study phases. RESULTS: During induction, cyclosporine at approximately 5.0 mg/kg per day produced a reduction in BSA of 70% or more in 86% of the patients. During maintenance, the median time to relapse was 6 weeks in both the placebo and cyclosporine 1.5 mg/kg per day groups, but was longer than the 24-week maintenance period in the 3.0 mg/kg per day group (p < 0.001 vs placebo). By the end of the maintenance period, 42% of the patients in the 3.0 mg/kg per day cyclosporine group had a relapse compared with 84% in the placebo group. Changes in laboratory values associated with the higher induction dosage generally exhibited partial or complete return toward mean prestudy baseline values during the maintenance phase, with the greatest degree of normalization in the placebo group. CONCLUSION: Cyclosporine, 3.0 mg/kg per day, adequately and safely maintained 58% of patients with psoriasis for a 6-month period after clearing of their psoriasis with doses of approximately 5.0 mg/kg per day.

Administration, Oral↗
PubMed1996

[Incidence of spontaneous bacterial peritonitis in cirrhotic patients with ascites. A two-year prospective study].

The prevalence of spontaneous bacterial peritonitis in patients with decompensated liver cirrhosis admitted to our unit during last two years was studied. Criteria of spontaneous bacterial peritonitis were positive bacteriology and greater than 250/mm3 polymorphonuclear leukocyte count. 84 examinations in 50 patients were made. Spontaneous bacterial peritonitis was diagnosed in 4 cases. E. coli, Klebsiella pneumoniae, alpha haemolyzing Streptococcus were isolated from ascitic fluid in positive cases. Three patients died despite of therapy, one patient recovered. Bacterascites (positive bacteriology without increased polymorphonuclear leukocyte count) was detected in two cases. Culture-negatív neutrocytic ascites (greater than 250/mm3 polymorphonuclear leukocyte count without positive bacteriology) was detected in four cases. The clinical picture of above-mentioned cases was symptomless. Low protein concentration of ascitic fluid (less than 10 g/l) predisposing to spontaneous bacterial peritonitis, was found in 15% of cases. Incidence of spontaneous bacterial peritonitis and equivocal states found by us was similar to the data given by the literature: 15-20%. Because of the high mortality rate and frequent symptomless course in cirrhotics, importance of diagnostic paracentesis is stressed.

Adult↗
PubMed1996

Studies on the chronic oral toxicity of an analgesic drug combination consisting of acetylsalicylic acid, paracetamol and caffeine in rats including an electron microscopical evaluation of kidneys.

The analgesic drug combination Thomapyrin consisting of acetylsalicylic acid (CAS 50-78-2, ASA), paracetamol (CAS 103-90-2, NAPAP) and caffeine (CAS 58-08-2) in the ratio 5:4:1 was investigated for its chronic toxicity in rats. For comparison the individual drugs ASA and NAPAP as well as the double combination ASA+NAPAP were tested in equipotent doses. 20 male and 20 female rats per group (Chbb:THOM/SPF) received doses of 50, 100 and 200 mg/kg of the combination ASA+NAPAP+caffeine, 45 and 180 mg/kg of the combination ASA+NAPAP, and 50 and 200 mg/kg of the individual drugs ASA or NAPAP over a period of 6 months. The daily dose was splitted into two parts and administered 3 h apart. The rats were single housed under standardized conditions with free access to food and drinking water. Plasma concentrations were measured in four additional animals of all high dose groups after the last dosing at seven time points. Besides the usual routine toxicological investigations the kidneys of five females per group were investigated by transmission electron microscopy. All investigations were performed according to GLP regulations. All animals behaved unobtrusively throughout the study with only minor impairment of general conditions in some animals of all ASA, ASA+NAPAP+caffeine and the high dose NAPAP groups. Dose related mortality was observed in the groups receiving ASA alone or in combination, partly with rales and tonic convulsions immediately prior to death. Body weight gain was decreased in males but not in females of the ASA+NAPAP+ caffeine and ASA groups. No consistent drug- and dose-dependent changes in hematological, clinico-chemical or urinanalytical parameters were observed, except for a slight increase in excretion of epithelial cells in both genders of the ASA groups. Plasma drug level monitoring demonstrated that the pharmacokinetics of ASA were not altered by co-administration of caffeine or NAPAP or vice versa. In males, maximum plasma concentrations (Cmax) and areas under the curve (AUC) for ASA and NAPAP tended to be slightly lower than in females. The plasma concentrations reached in the study represent a low multiple (2.2-7.9) of therapeutic plasma levels. Therefore, the results reported in the study can be considered representative for normal therapeutic use of the analgesic combination ASA+NAPAP+caffeine. Gastric erosions in the ASA and ASA+NAPAP+caffeine groups, increased kidney weights in females given 200 mg/kg ASA+NAPAP+caffeine, and dose-dependently increased liver weights in females given 200 mg/kg ASA and decreased liver weights in males at 100 and 200 mg/kg ASA-NAPAP+caffeine were the only consistent drug-induced changes observed at necropsy. Except for the above mentioned ulcer, all histopathological findings were iatrogenic or spontaneous lesions. The kidneys demonstrated initial stages of age-associated nephropathy at comparable incidence and severity in all groups including controls. Semi-thin section evaluation and transmission electron microscopy showed only minor changes. Taking all tubular and vascular changes together (total mean), the animals of the NAPAP group were slightly more affected than those of the other groups. Summing up it can be concluded that the nephrotoxic potential of the combination ASA+NAPAP+caffeine, if existing at all, was marginal even after prolonged administration, and that it does not exceed that of the monosubstances when given at pharmacologically equipotent doses and clinically relevant exposures.

Acetaminophen↗