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Biomedical subjects

J Kraus

Publications and source records attributed to J Kraus.

At least 91 records · Page 5Linked to original sources
PubMed1995

Molecular cloning and functional analysis of the rat mu opioid receptor gene promoter.

The rat mu opioid receptor gene promoter was cloned and characterized. It has a few features in common with the mouse gene, e.g. the lack of a classical TATA box and the fact that several transcriptional start sites are used. The overall homology between the two species is greater than 85%. Functional analysis of the promoter was performed using transient expression of rat mu opioid receptor-reporter gene constructs in the mu opioid receptor expressing cell line SH SY5Y and in non mu opioid receptor expressing cell lines. A promoter region was defined which confers both high basal and TPA and forskolin stimulated reporter gene expression in SH SY5Y cells.

Animals↗
PubMed1995

Identification of a cAMP-response element on the human proopiomelanocortin gene upstream promoter.

Proopiomelanocortin (POMC) is an example of a gene that is stimulated by cAMP without containing the classical cAMP-responsive element on its promoter. To characterize POMC sequences conferring cAMP responsiveness, we used mouse pituitary AtT-20 cells for transient expression of chloramphenicol acetyltransferase reporter gene constructs containing 5'-flanking sequences of the human POMC gene. A novel POMC-cAMP-responsive element (POMC-CRE) was identified, which is located between nucleotides -344 and -319 and which lacks the classical CRE core motif (CGTCA). Using gel retardation assays in combination with antibodies against CREB, we provided evidence that both AtT-20 cell derived and in vitro translated CREB proteins bind to the POMC-CRE and thus may be involved in the stimulation of the gene.

Animals↗
PubMed1995

Characterization of a Genomic Region Required for Production of the Antibiotic Pyoluteorin by the Biological Control Agent Pseudomonas fluorescens Pf-5.

A 21-kb region required for the biosynthesis of the polyketide antibiotic pyoluteorin by the biological control agent Pseudomonas fluorescens Pf-5 was identified and cloned. Seven previously isolated mutants deficient in pyoluteorin production (Plt(sup-)) had Tn5 insertions spanning the 21-kb region. Sequences flanking Tn5 inserts were cloned from genomic DNA of three Plt(sup-) mutants and used as probes to identify wild-type alleles of the plt loci from a genomic library of Pf-5. Five cosmids containing overlapping regions of genomic DNA hybridized to one or more of the probes. One cosmid, pJEL1938, contained the entire 21-kb region and, when introduced into a Plt(sup-) mutant, partially restored pyoluteorin production. To study the expression of the genes required for pyoluteorin biosynthesis, the transposon Tn3-nice, which contains a promoterless ice nucleation gene (inaZ) and a type I neomycin phosphotransferase gene, was introduced into the genomic plt region of Pf-5. Carbon sources that influenced pyoluteorin production by Pf-5 had parallel effects on ice nucleation activity of Pf-5 containing a genomic plt::Tn3-nice fusion, indicating that inaZ was transcribed from a promoter of the plt region. Cells of Pf-5 containing a genomic plt::Tn3-nice fusion expressed ice nucleation activity on cotton and cucumber seeds planted in field soil. The expression of plt genes by Pf-5 in the cucumber spermosphere was delayed in comparison with expression in the cotton spermosphere. This study demonstrates that genes required for pyoluteorin production were expressed in situ by the biological control bacterium.

Journal Article↗
PubMed1994

Loci associated with malignant progression in astrocytomas: a candidate on chromosome 19q.

WHO grades II and III astrocytomas frequently exhibit loss of genetic material on chromosomes 9p, 11p, 17p, 19q, and 22q, indicating that these chromosomal regions harbor tumor suppressor genes involved in the pathogenesis of astrocytic neoplasms. The present study was conducted to examine whether these genetic regions are involved in the process of malignant progression from astrocytoma WHO grade II (A II) to anaplastic astrocytoma WHO grade III (A III). We have analyzed 44 astrocytomas, i.e., 18 A II and 26 A III for loss of heterozygosity (LOH) on chromosomes 1p, 1q, 9p, 9q, 10p, 10q, 11p, 13q, 17p, 19p, 19q, and 22q and for amplification of the epidermal growth factor receptor gene. A polymerase chain reaction-based assay with microsatellite repeat sequences was used for the detection of polymorphisms on silver-stained polyacrylamide gels. LOH on 9p was seen in 1 of 18 (6%) informative cases of A II and 4 of 24 (17%) informative cases of A III. LOH on 17p was observed in 9 of 17 (53%) informative cases of A II and 15 of 26 (58%) informative cases of A III. LOH on 19q was detected in 2 of 18 (11%) informative cases of A II and in 12 of 26 (46%) informative cases of A III. The association of LOH on 19q with anaplasia in astrocytoma was significant (P = 0.015). Amplification of the epidermal growth factor receptor gene was not detected in A II or A III. These data suggest that a putative tumor suppressor gene on the long arm of chromosome 19 is a candidate for a gene associated with tumor progression in astrocytic gliomas.

Adult↗
PubMed1993

Immunophenotyping of mitotic cells from long-term cultures of chorionic villi.

Chromosomal mosaicism in chorionic villus samples (CVS) may arise from different sources, such as clonal diversity within the chorionic tissue or contamination with maternal cells. To determine the origin of karyotyped cells, we compared the immunocytochemical features of mitotic cells in CVS long-term cultures with histological sections of their tissue of origin, i.e. chorionic villi. Immunolabelling of intermediate filaments specific for epithelial cells (cytokeratin) and mesenchymal cells (vimentin) established that mitoses yielded from CVS long-term cultures indeed stem from independently growing clones derived from both the epithelial and mesenchymal parts of the chorionic villi. Thus, mosaicism in CVS cultures may reflect true genetic heterogeneity within the biopsy. However, epithelial chorionic cells undergo in vitro metaplasia leading to co-expression of cytokeratins and vimentin. Fetal-specific immune markers (beta-HCG and SP1-glycoprotein) are not reliably expressed in CVS cell culture.

Chorionic Gonadotropin↗
PubMed1993

Partial physical map of human chromosome 21 from fibroblast and lymphocyte DNA.

A partial physical map of the human chromosome 21 including 26 genes and anonymous sequences was established by pulsed-field gel electrophoresis analysis of restriction fragments obtained from lymphocyte and fibroblast DNAs. The sizes of the restriction fragments obtained by total digestion with eight different enzymes were compared in these two tissues. Differences resulting from the variations in the methylation state of the restriction sites were frequently observed. These differences and partial digestions were used to estimate the order and the distances between genes and sequences. Six linkage groups were defined: D21S13-D21S16, D21S1-D21S11, D21S65-D21S17, (D21S55,ERG)-ETS2, BCEI-D21S19-D21S42-D21S113-CBS-CRYA1, and COL6A2-S100B. For six intergenic distances the resolution of previous maps was significantly increased.

Blotting, Southern↗
PubMed1993

Ossifying renal tumor of infancy.

Ossifying renal tumor of infancy is a rare but distinctive tumor that presents as a mass in the pelvicaliceal system. It is usually suspected to be a calculus until surgical exploration reveals dense tumor attachment to the renal parenchyma. The histogenesis of this lesion has not been established. We present a case of this unusual neoplasm. A renal sparing procedure was performed on this biologically benign tumor. Followup after 20 months showed no evidence of recurrence.

Female↗
PubMed1993

Incidence, prevalence, and outcomes of end-stage renal disease patients placed in nursing homes.

We prospectively surveyed the 156 dialysis centers in Network 5 (MD, VA, WV, DC) for end-stage renal disease (ESRD) patients admitted to or begun on dialysis in nursing homes during a 21-month period (April 1, 1990 to December 31, 1991). In addition to this incidence data, information on patient demographics, social characteristics, pre-existent illnesses, and functional capacity (measured by activity of daily living [ADL] scores) was obtained. One hundred thirty-two centers (close to 90% of Network 5's approximately 9,000 patients) responded to the survey. Outcome data were gathered throughout the 21-month period and the subsequent 5 months. Seventy-three centers dialyzed 228 such patients during the 18-month period. Five centers that were located in the same building as a nursing home cared for 67 patients. The 228 patients, aged 17 to 101 years, were older (65.50 years +/- 14.2 [SD] v 53.7 +/- 16.4 years), and disproportionately female (62.2% v 48.3%), white (46.5% v 37.4%), and diabetic (57.9% v 29%) compared with the general network ESRD population (P < 0.05). On admission to the nursing home 47% of patients had organic heart disease, 35% had an organic brain syndrome, 22% had cerebrovascular diseases, 19% had amputations, and 18% were blind. The mean admission ADL score was 8.1 +/- 5.2 (maximum function, 18) and the patients did not differ regarding age, sex, race, or diabetes. Forty-three percent of patients lived alone or in sheltered housing before being placed in the nursing home.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1993

[Regional cytostatic perfusion of the extremities in patients with malignant melanoma and soft tissue sarcoma--therapeutic applications and results].

94 patients with malignant melanoma or soft tissue sarcoma of the extremities were submitted to isolated cytostatic limb perfusion. With palliative indication for treatment of malignant melanoma, the 5 year survival rate was 25% after perfusion with methotrexate and 50% after perfusion with melphalan. The adjuvant perfusion showed very good results, too. Furthermore, the authors report on their first experiences in regional cytostatic perfusion of soft tissue sarcoma and bone sarcoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Infantile sialic acid storage disease (ISSD). Report on first case in Czech Republic with biopsy and autopsy findings.

The first case of infantile sialic acid storage disease in Czech Republic is presented in a four-and-half year-old girl. The clinical phenotype consisted of moderate hepatosplenomegaly and skin hypopigmentation, early psychomotoric and developmental arrest, associated with truncal ataxia and lower extremities spasticity, extinguished acoustic and visual perception (optic atrophy without macular alteration) and remarkable automutilation phenomena. The appearance was normosomatic and there were minimal dysostotic changes. Skin and liver biopsy displayed moderate amount of lucent storage lysosomes in epithelial, mesenchymal, and neural elements. Alder-Reily granules were found in the bone marrow and peripheral blood cells. The urinary excretion of mucopolysaccharides and oligosaccharides was not increased. The autopsy showed heterogenous neuronal and glial brain storage (lucent lysosomes, lipopigment, membranous cytoplasmic bodies), severe hypomyelination and severe storage in the splenic sinus endothelium. Diagnosis was made by proving thirteen fold increase of free sialic acid in the fibroblast culture. It is pointed out that in the case of a mucopolysaccharidosis-like storage disease unexplainable by a hydrolytic enzyme deficiency, it is the enzyme product storage which must be suspected. At present, the only candidate is the sialic acid storage disease.

Child, Preschool↗
PubMed1992

Pythium aphanidermatum: culture, cell-wall composition, and isolation and structure of antitumour storage and solubilised cell-wall (1----3),(1----6)-beta-D-glucans.

Under optimal conditions for the culture of the fungus Phytium aphanidermatum, no polysaccharides were excreted into the medium. The mycelium contained up to 38% of a slightly branched, storage (1----3),(1----6)-beta-D-glucan with a MW of 20,000. The cell-wall polysaccharides of the mycelium comprised 18% of cellulose and 82% of (1----3),(1----6)-beta-D-glucans. Of the non-cellulosic glucans, approximately 33% could be solubilised by extraction with water at 121 degrees, and they had a MW of 10,000, were highly branched, and contained 6% of (1----6) linkages. Treatment of the cell wall with 0.1 M trifluoroacetic acid released approximately 50% of the non-cellulosic glucans. The acid-soluble cell-wall (1----3),-(1----6)-beta-D-glucans of lower MW (6000) were still highly branched and contained 14% of (1----6) and 8% of (1----4) linkages. The storage glucan and the hot-water-soluble cell-wall glucan exhibited strong activity against the Sarcoma 180 in CD-1 mice, whereas the acid-soluble cell-wall glucans were inactive. The hot-water-soluble cell-wall glucan was also active against the DBA/2-MC.SC-1 fibrosarcoma in DBA/2 mice.

Animals↗
PubMed1992

Synthesis and antitumour activity of derivatives of curdlan and lichenan branched at C-6.

Derivatives of curdlan and lichenan, linear (1----3)-beta-D- and (1----3/1----4)-beta-D-glucans, respectively, have been synthesised having alpha-L-arabinofuranosyl, alpha-L-rhamnosyl, beta-D-glucosyl, and beta-gentiobiosyl side chains attached at positions 6. These water-soluble derivatives, obtained by condensation of the 2,4- and 2,4-/2,3-di-O-phenylcarbamoyl derivatives of curdlan and lichenan, respectively, with appropriate ortho esters followed by saponification, were characterised by methylation analysis, g.p.c., and interaction with Congo Red. The curdlan derivatives and the lichenan derivative with few glucosyl branches were active against the Sarcoma 180.

Animals↗
PubMed1992

Synthesis and antitumour activity of sulfoalkyl derivatives of curdlan and lichenan.

2-Sulfoethyl, 3-sulfopropyl, and 4-sulfobutyl derivatives of the (1----3)-beta-D-glucan curdlan and the (1----3/1----4)-beta-D-glucan lichenan have been synthesised. The substituents are located mainly at positions 6. The curdlan derivatives strongly inhibited the growth of the Sarcoma 180 tumour, whereas the lichenan derivatives were inactive, indicating that a (1----3)-linked beta-D-glucan backbone is essential for activity.

Animals↗