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C Gebhardt

Publications and source records attributed to C Gebhardt.

At least 55 records · Page 3Linked to original sources
PubMed1996

A PCR-based approach for isolating pathogen resistance genes from potato with potential for wide application in plants.

Plant genes for pathogen resistance can be used to engineer disease resistant crops. Oligonucleotides were designed from sequence motifs conserved between resistance genes of tobacco and Arabidopsis thaliana and used as PCR primers in potato DNA. Amplification products were obtained that were homologous to known resistance genes and linked without recombination with the nematode resistance locus Gro1 and the Phytophthora infestans resistance locus R7 of potato. Map positions of PCR-derived potato gene fragments were also correlated with resistance loci of the related tomato and tobacco genomes. Our results indicate that plant resistance genes that are effective against nematodes, fungi, viruses and bacteria may be isolated based on common sequence motifs and PCR methodology.

Amino Acid Sequence↗
PubMed1996

[The significance of lymph- and hemangiosis carcinomatosa in colorectal carcinoma].

Between 1.1.1988 and 31.12.1989 306 patients underwent curative surgery for colorectal cancer at the surgical center of Nurnberg City hospital. The pathohistological findings showed that a carcinomatous lymphangiosis and hemangiosis (LH+) was present in 57 (18.6%) cases. The rate of metachronic metastases of the liver was significantly higher (38.2% vs. 19.6% p < 0.001) compared to patients without lymphangiosis and hemangiosis (LH-). There were also significant differences between the survival rates (5-year survival rate 50% vs. 63% p < 0.02). Analysing the lymph node stage and LH+ situation it was found that carcinomatous lymphangiosis and hemangiosis were already present in 7.2% of patients who didn't have tumorous infiltration of the lymph nodes (p NO/LH+). The 5-year survival rate was bad in both groups (54% vs. 49%).

Aged↗
PubMed1996

[Distal stenosis of the choledochus in chronic pancreatitis: endoscopic drainage or operation?].

With the less invasive techniques for complications regarding chronic pancreatitis, such as tubular choledochostenosis, the endoscopic transpapillary bile drainage therapy by means of endoprosthesis has undergone an enlargement of its indications range. Blocked and dislocated prostheses, however, further raise the already existing possibility of septic complications. With 15 out of 43 patients undergoing medium-term endodrainage treatment, we observed different resulting conditions of chronic cholestasis, such as abscess-forming cholangitis, hepatic abscesses, retroperitoneal phlegmon and sepsis up to biliary cirrhosis. Thus, in the case of chronic pancreatitis we still regard choledochostenosis- which, due to scarring, is mostly fixed-as a primary indication for operation.

Adult↗
PubMed1996

[Extensive surgery of colorectal carcinoma in the elderly--a justified therapy approach].

Over a 5-year period 1232 patients were operated on for carcinoma of the colon or rectum, 828 had curative surgery without and only 69 with resection of other organs. About half of the patients were 70 or more years old, but the older patients, especially in the extended resected cases, had the same or better 5-year survival and the same rate of complications or mortality. The overall prognosis depends on the complete resection of the tumor, the involvement of lymph nodes and the number of general risk factors, but not on the age of the patient.

Aged↗
PubMed1996

[Lymph- and haemangiosis carcinomatosa--an important prognostic factor in non-small-cell bronchial carcinoma (NSCLC)].

Between 1 Jan 1984-1 Jan 1990, 199 patients underwent curative (R0) surgery for non-small cell lung cancer. The pathohistological findings showed that a carcinomatous lymphangiosis and haemangiosis (L/H pos.) were present in 26 patients. In six patients, no lymph node metastases were detected. The median (22 mo. vs. 74 mo.) and 5-year survival (25% vs. 41%) were significantly (p < 0.001) higher compared to patients with and without lymphangiosis and haemangiosis carcinomatosa (L/H neg.). There were also significant (p < 0.05) differences in the survival time between pNO L/H neg. and pNO L/H pos. patients (median 74 mo. vs. 15 mo.-5 years 43% vs. 0%).

Capillaries↗
PubMed1995

A high-resolution map of the vicinity of the R1 locus on chromosome V of potato based on RFLP and AFLP markers.

The R1 allele confers on potato a race-specific resistance to Phytophthora infestans. The corresponding genetic locus maps on chromosome V in a region in which several other resistance genes are also located. As part of a strategy for cloning R1, a high-resolution genetic map was constructed for the segment of chromosome V that is bordered by the RFLP loci GP21 and GP179 and includes the R1 locus. Bulked segregant analysis and markers based on amplified fragment length polymorphisms (AFLP markers) were used to select molecular markers closely linked to R1. Twenty-nine of approximately 3200 informative AFLP loci displayed linkage to the R1 locus. Based on the genotypic analysis of 461 gametes, eight loci mapped within the GP21-GP179 interval. Two of those could not be separated from R1 by recombination. For genotyping large numbers of plants with respect to the flanking markers GP21 and GP179 PCR based assays were also developed which allowed marker-assisted selection of plants with genotypes Rr and rr and of recombinant plants.

Alleles↗
PubMed1995

Marker enrichment and high-resolution map of the segment of potato chromosome VII harbouring the nematode resistance gene Gro1.

The dominant allele Gro1 confers on potato resistance to the root cyst nematode Globodera rostochiensis. The Gro1 locus has been mapped to chromosome VII on the genetic map of potato, using RFLP markers. This makes possible the cloning of Gro1 based on its map position. As part of this strategy we have constructed a high-resolution genetic map of the chromosome segment surrounding Gro1, based on RFLP, RAPD and AFLP markers. RAPD and AFLP markers closely linked to Gro1 were selected by bulked segregant analysis and mapped relative to the Gro1 locus in a segregating population of 1105 plants. Three RFLP and one RAPD marker were found to be inseparable from the Gro1 locus. Two AFLP markers were identified that flanked Gro1 at genetic distances of 0.6 cM and 0.8 cM, respectively. A genetic distance of 1 cM in the Gro1 region corresponds to a physical distance of ca. 100 kb as estimated by long-range restriction analysis. Marker-assisted selection for nematode resistance was accomplished in the course of constructing the high-resolution map. Plants carrying the resistance allele Gro1 could be distinguished from susceptible plants by marker assays based on the polymerase chain reaction (PCR).

Animals↗
PubMed1995

Isolation, characterization and RFLP linkage mapping of a DNA repeat family of Solanum spegazzinii by which chromosome ends can be localized on the genetic map of potato.

In a random sample of 2263 cloned genomic DNA fragments of the wild potato species Solanum spegazzinii six related, highly repetitive fragments (SPG repeat family) were identified that were present in much higher copy numbers in S. spegazzinii when compared with the closely related cultivated potato S. tuberosum. The SPG repeat family was organized in long arrays of multiple copies. Cross hybridization experiments with 29 wild and cultivated Solanum species and with the related tomato showed specificity of the SPG repeat family for tuber-bearing Solanum species. Among tuber bearing Solanum species a high degree of variation was observed for restriction fragment length and copy number. The variation in copy number was not correlated with established taxonomic relationships between tuber-bearing Solanum species. DNA sequence analysis revealed a subrepeat structure of 120-140 base pairs embedded in longer repeat units of variable length. Length polymorphisms between highly repeated restriction fragments detected by the SPG probes were used for segregation- and linkage analysis in four mapping populations of potato, for which RFLP maps had been constructed. Twelve loci were identified, eleven of which mapped to the distal ends of nine linkage groups. All the evidence suggested that the SPG repeat family represents a satellite repeat members of which are localized in the subtelomeric region of potato chromosomes. The SPG repeat family could be used, therefore, for completing the genetic map of potato.

Base Sequence↗
PubMed1995

Molecular cloning and characterization of a soluble inorganic pyrophosphatase in potato.

A cDNA clone encoding a soluble inorganic pyrophosphatase (EC 3.6.1.1) of potato (Solanum tuberosum L.) was isolated by screening a developing tuber library with a heterologous probe. The central domain of the encoded polypeptide is nearly identical at the sequence level with its Arabidopsis homolog (J.J. Kieber and E.R. Signer [1991] Plant Mol Biol 16: 345-348). Computer-assisted analysis of the potato, Arabidopsis, and Escherichia coli soluble pyrophosphatases indicated a remarkably conserved organization of the hydrophobic protein domains. The enzymatic function of the potato protein could be deduced from the presence of amino acid residues highly conserved in soluble pyrophosphatases and was confirmed by its capacity to complement a thermosensitive pyrophosphatase mutation in E. coli. The potato polypeptide was purified from complemented bacterial cells and its pyrophosphatase activity was shown to be strictly dependent on Mg2+ and strongly inhibited by Ca2+. The subcellular location of the potato pyrophosphatase is unknown. Structure analysis of the N-terminal protein domain failed to recognize typical transit peptides and the calculated molecular mass of the polypeptide (24 kD) is significantly inferior to the values reported for the plastidic (alkaline) or mitochondrial pyrophosphatases in plants (28-42 kD). Two unlinked loci could be mapped by restriction fragment length polymorphism analysis in the potato genome using the full-length cDNA as probe.

Amino Acid Sequence↗
PubMed1995

[Repeat liver resection in colorectal liver metastases].

For patients with recurrent operable liver metastases from colorectal cancer operative resection is the only chance of getting rid of their tumorous disease for a longer time. As there are not therapeutic alternatives more and more authors are reporting on repeated resections of liver metastases. From 1986 to 1994 we performed 12 recurrent liver resections with curative intent in 8 patients suffering from liver metastases of colorectal cancer: 4 synchronous and 4 metachronous metastases were removed, the primary procedure being anatomic hemihepatectomy in 5 cases and segmentectomy or bisegmentectomy in 3 cases. The mean time interval between the first and the second resections was 14 (4-23) months. Two patients underwent 4 consecutive liver resections because of recurrent metastases. In these cases the interval between the second, third and fourth procedures was 10 months. The postoperative complication rate was 16% and not a single patient died in hospital. Three patients died an average of 28 (9-54) months after the last liver resection, and the other 5 patients are still alive after an average of 14 (4-28) months: 3 are free of tumor and 2 have recurrent metastases in the liver. Compared with untreated or only locally treated cases, patients in whom operative risk is low can achieve prolonged survival times after resections of colorectal metastases to the liver.

Adult↗
PubMed1994

ATP-sensitive K+ channels in heart muscle cells first open and subsequently close at maintained anoxia.

In ventricular myocardial cells of the guinea pig and the mouse, anoxia caused after a mean latency of 439 +/- 141 s and 129 +/- 23 s (mean +/- S.E.M.), respectively, a large current through KATP-channels. This current disappeared within several seconds when reoxygenating the cells but decayed also completely at maintained anoxia. The kinetics of the latter process, however, were much slower and obeyed an approximately monoexponential time course with time constants in the range of 30 s. The results suggest that in the ischaemic myocardium KATP-channels contribute only to the initial phase of extracellular K+ accumulation.

Adenosine Triphosphate↗
PubMed1994

[Enterocolic fistula due to foreign body perforation].

A 26-year-old man reported diarrhoea, abdominal pain and weight loss (16 kg in 3 weeks). Ultrasonography and computed tomography showed a 5 x 5 cm abnormal rosette-shaped mass with surrounding infiltration in the area of the left colic flexure. Laboratory tests indicated a florid inflammation. Coloscopy and double-contrast radiology of the colon revealed a fistula at the junction between sigmoid and descending colon. At laparotomy a large tumorous mass was found (18 x 15 x 10 cm), which was removed completely by partial resection of small intestine and colon. Histological examination revealed occlusion of an intestinal loop by a plastic foreign body (probably the cap of a household cleaner bottle). The patient would not provide any explanation of the circumstances leading to its ingestion.

Adult↗
PubMed1994

[Multivisceral resection of advanced colorectal cancer].

From 1 September to 1 January 1990, a total of 1232 patients underwent surgery for colorectal cancer. Resection was performed on 1112 (90.3%) patients. It was curative in 917 cases and palliative in 195. Multivisceral resection was necessary 82 times because of tumour infiltration of adjacent organs (curative: 69 cases; palliative: 13 cases). The complication rate (26.7% vs 27.5%) and mortality rate (3.4% vs 2.9%) were similar to those for curative resections without multivisceral extension. The 5-year survival rate was also similar in the two groups (58% vs 55%). These results show that curative multivisceral resections can lead to the same long-term results as conventional curative resections. These data are encouraging, and tumour infiltration of neighbouring organs should not be taken to demonstrate inoperability.

Abdominal Neoplasms↗
PubMed1994

Segregation analysis and RFLP mapping of the R1 and R3 alleles conferring race-specific resistance to Phytophthora infestans in progeny of dihaploid potato parents.

Phytophthora infestans (Mont.) de Bary is the most important fungal pathogen of the potato (Solanum tuberosum). The introduction of major genes for resistance from the wild species S. demissum into potato cultivars is the earliest example of breeding for resistance using wild germplasm in this crop. Eleven resistance alleles (R genes) are known, differing in the recognition of corresponding avirulence alleles of the fungus. The number of R loci, their positions on the genetic map and the allelic relationships between different R variants are not known, except that the R1 locus has been mapped to potato chromosome V. The objective of this work was the further genetic analysis of different R alleles in potato. Tetraploid potato cultivars carrying R alleles were reduced to the diploid level by inducing haploid parthenogenetic development of 2n female gametes. Of the 157 isolated primary dihaploids, 7 set seeds and carried the resistance alleles R1, R3 and R10 either individually or in combinations. Independent segregation of the dominant R1 and R3 alleles was demonstrated in two F1 populations of crosses among a dihaploid clone carrying R1 plus R3 and susceptible pollinators. Distorted segregation in favour of susceptibility was found for the R3 allele in 15 of 18 F1 populations analysed, whereas the R1 allele segregated with a 1:1 ratio as expected in five F1 populations. The mode of inheritance of the R10 allele could not be deduced as only very few F1 hybrids bearing R10 were obtained. Linkage analysis in two F1 populations between R1, R3 and RFLP markers of known position on the potato RFLP maps confirmed the position of the R1 locus on chromosome V and localized the second locus, R3, to a distal position on chromosome XI.

Alleles↗
PubMed1994

Quantitative resistance to Phytophthora infestans in potato: a case study for QTL mapping in an allogamous plant species.

Phytophthora infestans is the most important fungal pathogen in the cultivated potato (Solanum tuberosum). Dominant, race-specific resistance alleles and quantitative resistance--the latter being more important for potato breeding--are found in the germplasm of cultivated and wild potato species. Quantitative trait loci (QTLs) for resistance to two races of P. infestans have been mapped in an F1 progeny of a cross between non-inbred diploid potato parents with multiple alleles. Interval mapping methods based on highly informative restriction fragment length polymorphism markers revealed 11 chromosome segments on 9 potato chromosomes showing significant contrasts between marker genotypic classes. Whereas phenotypically no difference in quantitative resistance response was observed between the two fungal races, QTL mapping identified at least one race specific QT locus. Two QT regions coincided with two small segments on chromosomes V and XII to which the dominant alleles R1, conferring race specific resistance to P. infestans, Rx1 and Rx2, both inducing extreme resistance to potato virus X, have been allocated in independent mapping experiments. Some minor QTLs were correlated with genetic loci for specific proteins related to pathogenesis, the expression of which is induced after infection with P. infestans.

Alleles↗
PubMed1994

Transcripts accumulating during cold storage of potato (Solanum tuberosum L.) tubers are sequence related to stress-responsive genes.

During the adaptation of plants to low temperature, changes in gene expression can be induced in a variety of tissues. Low-temperature-regulated gene expression was studied in cold-stored potato (Solanum tuberosum L.) tubers by two-dimensional electrophoresis of in vitro translation products. As a response to cold treatment, the relative amount of mRNA encoding at least 26 polypeptides changed. By differential screening of a cDNA library, 16 clones corresponding to cold-inducible transcripts were isolated. They were classified into four non-cross-hybridizing groups. RNA hybridizations using representative clones from each group revealed different temporal accumulation patterns for the cold-inducible transcripts. mRNAs homologous to the cDNA clones were first detectable after 1 to 3 d of cold treatment, and the highest level of expression was reached after 3 to 7 d. Transcripts corresponding to cDNA clones CI13 and CI19 were transiently expressed, whereas the steady-state level remained high for cDNA clones CI7 and CI21 during the cold storage period of 4 weeks. The DNA sequences of two cDNA clones, CI7 and CI19, have been determined. The polypeptide predicted from the DNA sequence of CI19 is sequence related to small heat-shock proteins from other plant species. The deduced protein sequence of CI7 exhibits strong homology to the dehydrin/RAB group of dehydration stress- and abscisic acid-inducible polypeptides and to cold-induced proteins from Arabidopsis and spinach.

Amino Acid Sequence↗
PubMed1994

[Lesions of the bile ducts in open cholecystectomy].

The incidence of bile duct injuries during open cholecystectomy is around 2/1000. The most common lesion is complete divisions of the common bile duct, followed by partial divisions, stenoses or obstructions. The therapy of the lesions recognized intraoperatively is end-to-end anastomosis or, in the case of greater defects, hepaticojejunostomy. Strictures manifesting while after cholecystectomy can primarily be treated endoscopically, in divisions of obstructions hepaticojejunostomy is indicated; in high lesions the Hepp-Couinaud approach can be advocated.

Anastomosis, Surgical↗