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C Rupp

Publications and source records attributed to C Rupp.

17 recordsLinked to original sources
PubMed2001

A screen for genes required for meiosis and spore formation based on whole-genome expression.

BACKGROUND: Meiosis is the process by which gametes are generated with half the ploidy of somatic cells. This reduction is achieved by three major differences in chromosome behavior during meiosis as compared to mitosis: the production of chiasmata by recombination, the protection of centromere-proximal sister chromatid cohesion, and the monoorientation of sister kinetochores during meiosis I. Mistakes in any of these processes lead to chromosome missegregation. RESULTS: To identify genes involved in meiotic chromosome behavior in Saccharomyces cerevisiae, we deleted 301 open reading frames (ORFs) which are preferentially expressed in meiotic cells according to microarray gene expression data. To facilitate the detection of chromosome missegregation mutants, chromosome V of the parental strain was marked by GFP. Thirty-three ORFs were required for the formation of wild-type asci, eight of which were needed for proper chromosome segregation. One of these (MAM1) is essential for the monoorientation of sister kinetochores during meiosis I. Two genes (MND1 and MND2) are implicated in the recombination process and another two (SMA1 and SMA2) in prospore membrane formation. CONCLUSIONS: Reverse genetics using gene expression data is an effective method for identifying new genes involved in specific cellular processes.

Cell Nucleus↗
PubMed1999

[Malignant mesothelioma of the tunica vaginalis testis].

A case of malignant mesothelioma of the tunica vaginalis testis is reported in a 77-year-old male patient. There was no history of asbestos exposure. Recurrent right hydrocele with a papillar inguinal mass was the main clinical feature. An inguinal radical orchiectomy with en bloc resection of the surrounding tissue was performed. The therapeutic options for this rare, but aggressive neoplasm are discussed. Because of the disappointing results of antineoplastic chemotherapy or radiation therapy, the importance of initial radical surgical treatment with complete excision is emphasized.

Aged↗
PubMed1993

Acute hypersensitivity reactions to etoposide in a VEPA regimen for Hodgkin's disease.

PURPOSE: We report an unexpectedly high incidence of hypersensitivity to etoposide among 45 patients with newly diagnosed Hodgkin's disease treated with vinblastine, etoposide, prednisone, and doxorubicin (VEPA) plus radiation. PATIENTS AND METHODS: Twenty-three of 45 patients (51%) had one or more acute hypersensitivity reactions to etoposide administration. The 23 patients were 8 to 18 years of age (median, 15 years); 12 were males. Four patients had experienced prior allergic reactions to antibiotics or intravenous contrast media. RESULTS: Hypersensitivity reactions followed the first or second dose of VEPA in most cases. The reactions occurred at a median time of 5 minutes (range, 3 to 120) from the start of the etoposide infusion. Fifteen patients reacted early (within 10 minutes), four midway through the infusion, and four after completion of the infusion. Signs and symptoms included flushing, respiratory problems, changes in blood pressure, and abdominal pain with or without nausea and vomiting. Respiratory problems included dyspnea, chest pain/tightness, bronchospasm, and cyanosis. Symptoms were alleviated by discontinuing the etoposide infusions and administering diphenhydramine and/or hydrocortisone; epinephrine was required to reverse bronchospasm in three cases. All 23 patients recovered without adverse sequelae and were rechallenged with etoposide. Fifteen patients tolerated subsequent etoposide infused at a slower rate, with antihistamine and/or corticosteroid premedication; five had recurrent hypersensitivity despite these measures. Three of these five developed similar symptoms when teniposide was substituted for etoposide. Three patients who had isolated episodes of hypotension on completion of the etoposide infusion successfully received subsequent infusions without premedication or change in infusion rate or concentration. CONCLUSION: Despite this unexpectedly high incidence of hypersensitivity among Hodgkin's disease patients treated with etoposide, rechallenge with the drug was successful in 78% of cases.

Acute Disease↗
PubMed1986

Characterization of fibrinogen Milano I: amino acid exchange gamma 330 Asp----Val impairs fibrin polymerization.

An abnormal fibrinogen was found in two asymptomatic members (father and daughter) of the same family, originating from northern Italy. Routine coagulation studies revealed prolonged thrombin and reptilase clotting times. Plasma fibrinogen levels, as determined by a functional assay, were markedly diminished, whereas the heat precipitation method indicated normal fibrinogen values. On the basis of these findings, a tentative diagnosis of dysfibrinogenemia was made, and according to the accepted nomenclature, this fibrinogen variant was called "fibrinogen Milano l." The time course of fibrinopeptide A and B release from fibrinogen Milano l was normal, but the aggregation of fibrin monomers was delayed. Two-dimensional electrophoresis of reduced variant fibrinogen chains showed a defective gamma-chain with increased cathodic mobility. An abnormal electrophoretic mobility was observed also for the gamma-chain remnants of fibrinogen fragments D1 and D2 derived from fibrinogen Milano l, whereas the charge anomaly was lost after a further digestion by plasmin to D3, suggesting that the structure abnormality of this variant is situated in the region gamma 303-356. An abnormal peptide was isolated after cyanogen bromide cleavage of intact fibrinogen Milano l. This fragment spans from position gamma 311 to gamma 336. Amino acid analysis of the abnormal peptide showed the presence of valine and a diminished content of aspartic acid. Sequence analysis demonstrated an amino acid exchange Asp----Val in the gamma-chain at position 330.

Adult↗
PubMed1983

[Fibrinogen Bern II: hereditary fibrinogen variant with amino acid substitution of arginine replaced by histidine in position 16 of the A alpha chain].

The number of described individuals with congenital dysfibrinogenemia continuously increases, but only a few fibrinogen variants have thus far been characterized with respect to their structural defect. Fibrinogen Bern II is a hereditary fibrinogen variant with impaired release of fibrinopeptide A (FPA) and a markedly prolonged coagulation time. It turned out that only half of the FPA was cleaved off at normal rate while the residual FPA was released much more slowly and incompletely, unless high thrombin concentrations were used. Amino acid analysis of normal and abnormal FPA revealed that the abnormal peptide, in contrast to the normal, contained histidine but hardly any arginine. It is therefore concluded that fibrinogen Bern II undergoes substitution of arginine in position 16 of the A alpha-chain by histidine. Thus, the structural alteration is identical with that of seven other recently described variants. The presence of 50% normal fibrinogen molecules provides the normal hemostasis in the heterozygous carriers of the Bern II-dysfibrinogenemia.

Afibrinogenemia↗
PubMed1983

Inhibition of fibrin polymerization by fragment d is affected by calcium, Gly-Pro-Arg and Gly-His-Arg.

Fibrinopeptides A and B were removed from purified human fibrinogen by bovine thrombin, whereas the snake venom protease batroxobin only split fibrinopeptide A from fibrinogen. Aggregation of the resulting desAB- and desA-fibrin monomers was evaluated by recording the turbidity of incubation mixtures. Fibrin assembly was strongly accelerated by increasing the calcium concentration from 10(-5) to 10(-3) M. Fragment D was obtained from fibrinogen by proteolytic degradation with plasmin in the presence of Ca2+. At a 4-fold molar concentration relative to fibrinogen, fragment D dramatically inhibited fibrin polymerization at up to 10(-4) M Ca2+. This anticlotting activity was, however, much less pronounced at 10(-3) M Ca2+. The thrombin clotting time, measured on human plasma, was prolonged by fragment D in a dose-dependent manner. In citrate-containing plasma, the fibrinogen clotting was significantly delayed by an equimolar concentration of fragment D. In barium sulfate-adsorbed oxalated plasma, containing 2.5 mM Ca2+, the same amount of fragment D hardly affected fibrin polymerization. We conclude that fragment D has no important anticlotting effect under physiological conditions. The synthetic peptide Gly-Pro-Arg, corresponding to the amino-terminal sequence of the fibrin alpha-chain, inhibited aggregation of both desA-fibrin and desAB-fibrin at 10(-3) M Ca2+. The inhibition of desAB-fibrin polymerization by Gly-Pro-Arg was abolished at 10(-5) M Ca2+. In addition, Gly-Pro-Arg depressed the anticlotting activity of fragment D at low calcium concentration. An analogue of the amino-terminus of fibrin beta-chain, Gly-His-Arg, strongly accelerated aggregation of desA-fibrin monomers, but only moderately enhanced polymerization of desAB-fibrin monomers at 10(-5) M Ca2+, both in the presence and in the absence of fragment D. This activating effect of Gly-His-Arg was abolished at 10(-3) M Ca2+. It is suggested that the binding of calcium, Gly-His-Arg, and possibly also Gly-Pro-Arg, induces a conformational change in fibrin monomers and thus accelerates the polymerization process.

Animals↗
PubMed1982

Effect of calcium and synthetic peptides on fibrin polymerization.

Human fibrinogen was subjected to limited proteolytic attack by thrombin, batroxobin or Agkistrodon contortrix thrombin-like enzyme, yielding desAB-, desA- or desB-fibrin monomers, respectively. Turbidity curves demonstrated that, with all three enzymes, the polymerization process was strongly accelerated by increasing the calcium concentration from 10(-5) M to 10(-4) M. Synthetic peptide Gly-His-Arg (5 mM), an analogue of the aminoterminal sequence of fibrin beta-chain, inhibited aggregation of desB-fibrin monomers at physiological calcium concentration whereas it enhanced aggregation of desA- and desAB-fibrin monomers at calcium concentrations below 10(-4) M. On the other hand, Gly-Pro-Arg (1 mM) corresponding to the amino-terminus of fibrin alpha-chain, dramatically inhibited aggregation of both desA- and desB-fibrins, but it only moderately affected the polymerization of thrombin-induced monomers. We conclude that the observed effects of Gly-Pro-Arg and Gly-His-Arg are not due solely to their competition with fibrin amino-termini for the respective binding sites in the D-domain, but rather reflect conformational changes in fibrin monomers which affect the polymerization process.

Batroxobin↗
PubMed1981

[Fibrinogen Bern I and fibrinogen Bern II: 2 hereditary fibrinogen variants with diverse biochemical properties].

Two inherited fibrinogen variants, fibrinogen Bern I and fibrinogen Bern II, have been partially characterized. The markedly prolonged thrombin clotting times observed with both variants result from impaired fibrin monomer aggregation. Complete correction of this polymerization defect at physiological calcium concentrations has been achieved for fibrinogen Bern I. This variant also exhibits a charge abnormality in the gamma-polypeptide chain, an increased sialic acid content and defective calcium binding by the C-terminal part of the molecule. Fibrinogen Bern II, on the other hand, exhibits a defect which, although located at a site important for polymerization, is not influenced by the binding of calcium ions.

Binding Sites↗
PubMedDate not supplied

Cost reduction after introduction of a multidisciplinary infectious disease service at a German university hospital.

BACKGROUND: In 1997 an infectious disease service (IDS) similar to those in the US was established at a university hospital in Munich, Germany. PATIENTS AND METHODS: We assessed the economic impact of the new policy by performing a cost comparison analysis. Inpatients with pneumonia, skin infections/cellulitis, urinary tract infections (UTI) and bacteremia/sepsis were assigned to two groups: patients from a 6-month period after the establishment of the IDS (post-IDS group) were compared with similar patients before the implementation of the ID-service (pre-IDS group). Costs of microbiological investigation (MB), antibiotic treatment (AB), clinical imaging (CI), total costs and length of antibiotic therapy were analyzed. RESULTS: Patients with UTIs in the post-IDS group had 39% fewer MBs (p<0.05) than patients in the pre-IDS group, resulting in a 33% decrease in average MB costs (p<0.05). In the total group, in which subgroups with pneumonia, skin infection and UTI were summarized, the post-IDS group had 37% fewer MBs (p<0.05) resulting in MB cost reductions of 34% (p<0.05). There were no significant differences in expenditures for AB and CI and in the average length of antibiotic therapy. CONCLUSION: This study shows that continuous consultation by an IDS does not increase diagnostic and treatment costs, but results in significant cost reductions.

Aged↗