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B Rolinski

Publications and source records attributed to B Rolinski.

29 records · Page 2Linked to original sources
PubMed1997

[Comparative investigation of the efficacy of two nucleocapsid analogs in FIV infected cats].

Antiviral activity of the acyclic nucleoside phosphonates 9-(2-phosphonylmethoxyethyl)adenine (PMEA) and 9-(3-fluoro-2-phosphonylmethoxypropyl)adenine (FPMPA) against feline immunodeficiency virus (FIV) was investigated in field cats. The study was designed as a placebo-controlled double-blind study enrolling 27 FIV infected cats. Nine cats received PMEA at a dosage of 10 mg/kg body weight, nine cats received FPMPA at a dosage of 25 mg/kg body weight. A variety of parameters were established to evaluate the therapeutic efficacy of the compounds. The improvement was monitored by different aspects: clinical status, index of Karnofsky modified for the cat, laboratory parameters, immunological parameters, surrogate markers, and a virological parameter. Concerning the clinical and immunological parameters cats of both treatment groups disclosed a relevant improvement. Efficacy of antiviral treatment was a little bit higher in the cats treated with PMEA than in the animals injected with FPMPA. However, side effects were also more prominent in the PMEA treated group.

Adenine↗
PubMed1996

Mitochondrial and cytosolic branched-chain amino acid transaminases from yeast, homologs of the myc oncogene-regulated Eca39 protein.

We have isolated a high copy suppressor of a temperature-sensitive mutation in ATM1, which codes for an ABC transporter of Saccharomyces cerevisiae mitochondria. The suppressor, termed BAT1, encodes a protein of 393 amino acid residues with an NH2-terminal extension that directs Bat1p to the mitochondrial matrix. A highly homologous protein, Bat2p, of 376 amino acid residues was found in the cytosol. Both Bat proteins show striking similarity to the mammalian protein Eca39, which is one of the few known targets of the myc oncogene. Deletion of a single BAT gene did not impair growth of yeast cells. In contrast, deletion of both genes resulted in an auxotrophy for branched-chain amino acids (Ile, Leu, and Val) and in a severe growth reduction on glucose-containing media, even after supply of these amino acids. Mitochondria and cytosol isolated from bat1 and bat2 deletion mutants, respectively, contained largely reduced activities for the conversion of branched-chain 2-ketoacids to their corresponding amino acids. Thus, the Bat proteins represent the first known isoforms of yeast branched-chain amino acid transaminases. The severe growth defect of the double deletion mutant observed even in the presence of branched-chain amino acids suggests that the Bat proteins, in addition to the supply of these amino acids, perform another important function in the cell.

Amino Acid Sequence↗
PubMed1995

[Ocular microangiopathy syndrome in patients with AIDS is associated with increased plasma levels of the vasoconstrictor endothelin-1].

OBJECTIVE: Ocular microangiopathic syndrome is the most frequent ophthalmic finding in patients suffering from the acquired immunodeficiency syndrome (AIDS). Ocular microvascular changes including cotton-wool spots are closely associated with neuroretinal and cognitive deficits in patients infected with the human immunodeficiency virus type 1 (HIV-1). Endothelin-1 is a recently identified cytokine with potent vasoconstrictor activity which is associated with various diseases involving vascular structures. METHODS: We studied 29 patients with AIDS by indirect ophthalmoscopy and by slit lamp biomicroscopy, and endothelin-1 immunoreactivity (IR) was measured in plasma by radioimmunoassay. Cotton-wool spots were counted as indicator of retinal microvasculopathy. Conjunctival bloodflow sludging in conjunctival vessels was measured by a standardized rating scale as indicator of conjunctival microvasculopathy. Parameters of immunosystemic damage were determined as covariates. RESULTS: Endothelin-1 IR was closely associated with the number of cotton-wool spots (Spearman r = 0.53, p < 0.01) and with the extent of conjunctival blood-flow sludging (r = 0.61, p < 0.001). The level of significance became stronger applying analysis of covariance with Endothelin-1 IR as dependent variable and number of cotton-wool spots (p < 0.0001) or extent of conjunctival blood-flow sludging (p < 0.0001) as independent variables. CONCLUSION: Our data are consistent with the hypothesis that the vasoconstrictor endothelin-1 has an important role in the pathogenesis of HIV-1-related ocular microangiopathic syndrome. As HIV-1-related ocular microangiopathic syndrome is associated with neuroretinal and cognitive deficits in patients with HIV-1 disease the therapeutic use of endothelin antagonists currently under investigation should be discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Mutations in the gene for X-linked adrenoleukodystrophy in patients with different clinical phenotypes.

Recently, the gene for the most common peroxisomal disorder, X-linked adrenoleukodystrophy (X-ALD), has been described encoding a peroxisomal membrane transporter protein. We analyzed the entire protein-coding sequence of this gene by reverse-transcription PCR, SSCP, and DNA sequencing in five patients with different clinical expression of X-ALD and in their female relatives; these clinical expressions were cerebral childhood ALD, adrenomyeloneuropathy (AMN), and "Addison disease only" (ADO) phenotype. In the three patients exhibiting the classical picture of severe childhood ALD we identified in the 5' portion of the X-ALD gene a 38-bp deletion that causes a frameshift mutation, a 3-bp deletion leading to a deletion of an amino acid in the ATP-binding domain of the ALD protein, and a missense mutation. In the patient with the clinical phenotype of AMN, a nonsense mutation in codon 212, along with a second site mutation at codon 178, was observed. Analysis of the patient with the ADO phenotype revealed a further missense mutation at a highly conserved position in the ALDP/PMP70 comparison. The disruptive nature of two mutations (i.e., the frameshift and the nonsense mutation) in patients with biochemically proved childhood ALD and AMN further strongly supports the hypothesis that alterations in this gene play a crucial role in the pathogenesis of X-ALD. Since the current biochemical techniques for X-ALD carrier detection in affected families lack sufficient reliability, our procedure described for systematic mutation scanning is also capable of improving genetic counseling and prenatal diagnosis.

Adrenoleukodystrophy↗
PubMed1994

Endothelin-1 immunoreactivity in plasma is elevated in HIV-1 infected patients with retinal microangiopathic syndrome.

Endothelin-1 is a recently identified cytokine with potent vasoconstrictor activity which is associated with various diseases involving blood vessels. HIV-1 related retinal microangiopathic syndrome is a frequent finding in patients with AIDS or AIDS-related complex, presenting predominantly with retinal cotton-wool spots. We investigated 55 HIV-1 infected patients by ophthalmoscopy and for endothelin-1 immunoreactivity in plasma and an additional 76 HIV-1 infected patients only for endothelin-1 levels. For reference values 13 age-matched healthy subjects were studied. In 18 of 55 patients (33%) investigated ophthalmoscopically we found evidence of microangiopathic syndrome. Overall, the mean endothelin-1 immunoreactivity in plasma of HIV-1 infected patients was significantly elevated as compared to controls (4.28 +/- 3.62 versus 2.72 +/- 0.67 fmol/ml, P < 0.0001). HIV-1 infected patients with retinal microangiopathic syndrome had significantly higher plasma levels of endothelin-1 immunoreactivity (4.59 +/- 1.38 fmol/ml) compared to HIV-1 infected patients without microangiopathic syndrome (3.18 +/- 1.64 fmol/ml, P = 0.003). Correlation analysis revealed that endothelin-1 immunoreactivity in plasma had no significant association with disease progression, CD4 cell count, beta 2-microglobulin, neopterin, or age. Endothelin-1 immunoreactivity in plasma was correlated exclusively with retinal microangiopathic syndrome in one or both eyes (r = 0.45, P = 0.0006) and with the number of cotton-wool spots (r = 0.50, P = 0.0001). In conclusion, HIV-1 related retinal microangiopathic syndrome is associated with elevated plasma levels of endothelin-1. By virtue of its potent vasoconstrictor activity endothelin-1 may be involved in the pathogenesis of HIV-1 related vascular disease.

Adult↗
PubMed1994

Determination of endothelin-1 immunoreactivity in plasma, cerebrospinal fluid and urine.

Endothelin-1 (ET-1) is a potent vasoconstrictor peptide apparently involved in a number of vascular diseases in man. Nonetheless, its determination in biological samples is difficult, and data on plasma or urine concentrations are controversial. We investigated different sample preparation procedures as well as different radioimmunoassays for their influence on ET-1 measurement. Recovery of ET-1 depended on the extraction procedure, the type and size of the extraction columns and on the biological matrix itself. Incomplete removal of matrix components by the extraction leads to the formation of particulate matter in the evaporated eluate. When dissolved in assay buffer, ET-1 was found to be absorbed to and only partly released from these particulates, so that it was not accessible for measurement in a radioimmunoassay. This was the case for all extraction procedures investigated except for that involving acetic acid. HPLC analysis of spiked samples revealed that ET-1 is in part degraded during extraction, most probably to Meth-sulphoxide ET-1. Dilution curves of synthetic pure ET-1 standards from different suppliers, prepared either in plasma with subsequent extraction or in assay buffer of the respective radioimmunoassay, resulted in considerable differences in the measured values for ET-1-immunoreactivity. Every radioimmunoassay tested had a specific pattern of recognizing different synthetic ET-1 standards. In conclusion, the measurement of ET-1-immunoreactivity is strongly influenced by the experimental conditions of sample preparation as well as by the radioimmunoassay employed.

Absorption↗
PubMed1994

Liposomal doxorubicin in the treatment of advanced AIDS-related Kaposi sarcoma.

Neither single-agent therapy nor any combination treatment has been satisfactory enough to be regarded as standard in systemic advanced Kaposi sarcoma. In an attempt to achieve high efficacy in combination with low toxicity, we used a new liposomal formulation of doxorubicin. Pharmacologic data had established a long plasma half-life, an increased accumulation in tumor tissue, and a decrease in uptake by tissues such as liver, spleen, and bone marrow. In a phase I/II open-label, dose-escalating trial 40 male AIDS patients with advanced Kaposi sarcoma were enrolled to receive intravenous "stealth" liposomal doxorubicin biweekly at doses of 10 mg/m2 (n = 10), 20 mg/m2 (n = 27), and 40 mg/m2 (n = 3). The median CD4 count at baseline was 25/microL. After six cycles (12 weeks), 39 patients were evaluable. Three patients (7.5%) showed a complete response, which was histologically confirmed. A partial response was documented in 33 patients (85%). Stable disease was observed in three patients (7.5%). During a median treatment duration of 25 weeks, four patients developed stomatitis (10%), and four patients (10%) experienced alopecia. The most frequent hematologic toxicity was neutropenia. Grade 4 neutropenia was seen in 42.5%, and grade 3 toxicity was seen in 30%. Toxicity was dose-dependent and more frequent in the 40 mg/m2 stratum. During a median observation period of 25 weeks, opportunistic infections occurred in 57.5% of the patient population. We conclude that liposomal doxorubicin at dose levels of 10 and 20 mg/m2 is safe and effective for treatment of advanced Kaposi sarcoma in AIDS. A controlled trial comparing liposomal doxorubicin to conventional combination therapy is underway.

AIDS-Related Opportunistic Infections↗
PubMed1991

Evaluation of saliva as a specimen for monitoring zidovudine therapy in HIV-infected patients.

To facilitate studies of the pharmacokinetic properties of zidovudine, the relationship between plasma and salivary concentrations of the drug was studied, after oral dosage, in 10 HIV-infected patients. Zidovudine concentrations were determined in plasma, unstimulated mixed saliva and citric-acid-stimulated mixed saliva over a period of 3 1/2 hours by high-performance liquid chromatography. Correlation coefficients were r = 0.97 (P less than 0.0001) for stimulated saliva compared with plasma and r = 0.89 (P less than 0.0001) for unstimulated saliva, with average values in unstimulated saliva being 113.8 +/- 44.6% in plasma and 67.8 +/- 25.4% in stimulated saliva. Stimulated saliva values found to be 70% of the total reflected the concentration of the unbound drug in plasma. Except for a shorter half-life time (t1/2) in saliva, pharmacokinetic parameters showed a good correlation in the three types of specimen. These findings and the convenience of sample collection suggest that citric-acid-stimulated saliva might be an appropriate specimen for monitoring zidovudine therapy.

Adult↗
PubMedDate not supplied

Pharmacokinetics of orally administered zidovudine in HIV-infected children and adults.

The pharmacokinetics of oral zidovudine in HIV-infected children and adults are reported. Fourty-six patients were investigated. For data analysis three groups of similar size were formed: young children 4 months-4 years, n = 15 (group 1), older children up to 13 years, n = 16 (group 2) and young adults, n = 15 (group 3). After a single oral dose repeated blood samples were taken 1/2 hourly during a period of 4 hours and zidovudine concentrations in plasma were determined by high performance liquid chromatography. For better comparison of dose dependent parameters peak concentrations (Cmax) and the area under the time-concentration curves (AUC) were normalized either to the dose/body weight (bw) or the dose/body surface area (bs), respectively. Time to reach peak concentrations and mean terminal elimination half-life times (t1/2 beta = 63.4 +/- 47.6, 74.9 +/- 54.9 and 56.9 +/- 16.4 min in group 1, 2 and 3, respectively, mean +/- SD) were not significantly different between the three groups. With normalization to dose/bw young children in comparison to adults had significantly lower Cmax (2.7 +/- 1.3 vs. 4.6 +/- 2.4 mumol/l, p = 0.016) and AUC (226 +/- 108 vs. 373 +/- 224 mumol.min/l, p = 0.038). Group 2 gave intermediate values. However, with normalization to dose/bs differences in Cmax (6.5 +/- 3.3, 7.3 +/- 4.2 and 6.8 +/- 3.6 mumol/l, in group 1, 2, and 3, respectively) and AUC (563 +/- 313, 691 +/- 351 and 555 +/- 342 mumol.min/l, in group 1, 2 and 3) were not significant between the three groups. It is likely that changes in body water content with age may account for most of these differences observed. In conclusion, a similar pharmacokinetic profile was found in children older than 3 months as compared to older children or adults.

Administration, Oral↗