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H Schmidt

Publications and source records attributed to H Schmidt.

At least 307 records · Page 17Linked to original sources
PubMed1998

Molecular cloning and sequence analysis of the Schizosaccharomyces pombe ade10+ gene.

We have cloned and sequenced the Schizosaccharomyces pombe ade10 gene encoding 5-phosphoribosyl-4-carboxamide 5-aminoimidazole transformylase inosine monophosphate cyclohydrolase. The sequence has an uninterrupted open reading frame of 1755 nucleotides corresponding to 585 amino acid residues. The deduced amino acid sequence shows a high degree of similarity to the purH gene product of many species, including Saccharomyces cerevisiae, human, chicken and Escherichia coli. Moreover our data indicate that intrachromosomal recombination in Schiz. pombe is enhanced if the ade10 gene product is defective.

Amino Acid Sequence↗
PubMed1998

A 3.3-kb plasmid of enterohemorrhagic Escherichia coli O157:H7 is closely related to the core region of the Salmonella typhimurium antibiotic resistance plasmid NTP16.

A restriction enzyme map was constructed of a 3.3-kb plasmid derived from enterohemorrhagic Escherichia coli O157:H7 strain 4821 using the enzymes SmaI, HpaI, FokI, HaeIII, StyI, RsaI, Bg/II, ClaI, and EcoRV. The molecular size of p4821 was 3307 bp, determined by nucleotide sequencing. Homology searches in the EMBL database library revealed that the nucleotide sequence of P4821 is similar (> 98%) to the core region of the antibiotic resistance plasmid NTP16 of Salmonella typhimurium strains. Nucleotide sequence analysis showed that p4821 contains all the information necessary for its replication, stability, and mobilization. However, the lack of tra genes indicates that the plasmid is nonconjugative. A possible transposon insertion site was found in p4821 but two such sites were found at the boundaries between the core region and the antibiotic resistance encoding transposons in plasmid NTP16. Using a hybridization assay, we determined that of 50 E. coli O157:H7 strains isolated in 1996 in Würzburg, Germany from patients with diarrhea and hemolytic-uremic syndrome, 4 strains (8%) contained plasmid p4821-specific sequences.

Diarrhea↗
PubMed1998

p53 status in radiation-induced soft-tissue sarcomas.

BACKGROUND: Following therapeutic irradiation after a latency period of many years radiation-induced tumors, often sarcomas, can arise. Results of radiation-induced DNA damage can be 1. p53 over-expression, inducing growth arrest or apoptosis, and 2. occurrence of mutations, frequently including the p53 gene, as one molecular promotor for carcinogenesis. We were interested whether radiation-induced sarcomas are associated with alterations of the p53 status. MATERIAL AND METHODS: Samples from 11 radiation-induced soft-tissue sarcomas (STS) were studied by a non-radioactive PCR-SSCP sequencing analysis and by immunohistochemistry with five antibodies for their p53 status. RESULTS: A tumor of one patient possessed a G->A transition in codon 280 (exon 8). Of 11 tumors, 9 showed nuclear p53 positivity, detected by monoclonal antibody DO-1. Of these 9 patients, 7 died during the observation period, whereas the 2 patients with DO-1 negative tumor samples are still alive. CONCLUSIONS: p53 over-expression and p53 mutation occur in radiation-induced STS. p53 status is expected to have prognostic impact for radiation-induced STS.

Adult↗
PubMed1998

Differential sensitivity of macrophages to bradykinin.

In this report, we investigated the responsiveness of subpopulations of elicited peritoneal macrophages between each other compared to resident tissue macrophages of alveoli of guinea pig to the action of bradykinin. Bradykinin stimulated the secretion of superoxide radical, arachidonic acid and prostaglandin E2 (PGE2) via the bradykinin B2 receptor subtype in peritoneal macrophages, indicated by complete inhibitory effect of the bradykinin B2 receptor antagonist HOE 140. The extent of the secretion, however, varied substantially between macrophages of different size. The highest level of the secretion was observed in the fraction containing the intermediate-size macrophages, while progressively lower level of the secretion was observed with decreasing size. In contrast, large macrophages obviously lost their secretory ability. Additionally, the bradykinin-stimulated release of cyclooxygenase products exerted an inhibitory action on NADPH-oxidase activity depending on size and stage of maturation/activation of macrophages, as judged by an increase in superoxide radical generation by indomethacin (100 microM) preincubation of cells. Furthermore, the investigation of resident tissue macrophages of alveoli has shown that these cells also express the bradykinin B2 receptor subtype. However, the receptor activity measured by bradykinin-induced increase in intracellular free calcium [Ca2+]i was very low compared to elicited peritoneal macrophages. These findings indicate that the stage of differentiation/maturation and activation of macrophages may be important for the ability of bradykinin to stimulate these cells to inflammatory responses in vivo.

Animals↗
PubMed1998

[Tracheobronchoscopy and esophagoscopy in otorhinolaryngology. An assessment of current status].

Its is the task of each medical specialty to develop guidelines for diagnosis and therapies. Examinations done by several specialties should follow a common consensus. A randomized survey at 70 German ENT departments investigated the current position of tracheobronchoscopy and esophagoscopy at each institution. Sixty questionnaires were evaluable. Altogether 8,295 tracheobronchoscopies and 10,404 esophagoscopies were performed. Thirty-six percent of all tracheobronchoscopies and 6% of all esophagoscopies were done with a flexible system. Approximately 58% of all tracheobronchoscopies and 55% of all esophagoscopies were performed for tumor staging. Complications during tracheobronchoscopy occurred in 0.8% of cases and in 0.58% of the esophagoscopies. Using these data an interdisciplinary quality assurance concept was developed for tracheobronchoscopy and esophagoscopy. Current experience has shown that a otolaryngologists in Germany mainly perform rigid tracheobronchoscopy and esophagoscopy. Although endoscopy is mostly done in cases with varied anatomic structures, complications are very rare and comparable to flexible techniques. Greater experience with flexible systems also is to be encouraged in ENT departments.

Bronchoscopes↗
PubMed1998

[Flexible endoscopy in the ENT area].

Although rigid esophagoscopy and tracheobronchoscopy have always been a domain of the ENT surgeon, the development of flexible endoscopes has increased diagnostic and therapeutic indications in clinical practice. Component elements of fiberendoscopes and CCD endoscopes are shown. Techniques in flexible bronchoscopy, flexible esophagoscopy and rhinolaryngoscopy are explained. General and special indications of fiberendoscopy are listed. Possibilities and limitations of flexible bronchoscopy are shown. Flexible techniques for removing foreign bodies of the esophagus and indications for mini-endoscopy are demonstrated. Experience has shown that flexible endoscopy has brought the diagnosis and therapy of tubular organs into a new perspective. Since flexible techniques do not replace rigid ones and complement each another, ENT surgeons must be trained in both techniques.

Bronchoscopes↗
PubMed1998

Influence of N-acetylcysteine treatment on endotoxin-induced microcirculatory disturbances.

OBJECTIVES: To determine the influence of N-acetylcysteine (NAC) in a treatment model, its effects on endotoxin-induced leukocyte-endothelial cell adhesion, vascular leakage, and venular microhemodynamics in postcapillary venules of rat mesentery. DESIGN: Prospective, randomized, controlled, experimental study. SETTING: Animal research laboratory. SUBJECTS: 40 male Wistar rats. INTERVENTIONS: The rats randomly received one of four treatments: infusion of saline (SAL) or Escherichia coli lipopolysaccharides (LPS) followed by treatment with saline (SAL) or NAC (150 mg.kg-1 body weight) 30 min after induction of endotoxemia. MEASUREMENTS AND MAIN RESULTS: Leukocyte adherence, red blood cell velocity, and vessel diameters in postcapillary venules of rat mesentery were evaluated every 30 min over a period of 120 min using in vivo videomicroscopy. Vascular permeability was determined by measuring the extravasation of fluorescence-labeled albumin. Venular wall shear rate was calculated from red cell velocity, and vessel diameter. NAC in rats without endotoxemia (SAL + NAC group) compared to the control group (SAL + SAL) did not change microcirculatory parameters in postcapillary venules of rat mesentery. In both LPS-treated groups (LPS + SAL and LPS + NAC), leukocyte adherence increased after just 30 min. NAC treatment prevented a further increase in leukocyte adherence and attenuated the extravasation of fluorescence-labeled albumin during endotoxemia. Venular diameters remained unchanged, while erythrocyte velocity decreased in the LPS + SAL group. This led to a lower venular wall shear rate in this group. CONCLUSIONS: Treatment with NAC attenuates endotoxin-induced leukocyte adherence and macromolecular leakage in postcapillary venules of rat mesentery, showing that NAC is also effective after the onset of endotoxemia.

Acetylcysteine↗
PubMed1998

The genes lmbB1 and lmbB2 of Streptomyces lincolnensis encode enzymes involved in the conversion of L-tyrosine to propylproline during the biosynthesis of the antibiotic lincomycin A.

The genes lmbA,B1,B2 in the lincomycin A production gene cluster of Streptomyces lincolnensis were shown to form a common transcription unit with the promoter located directly upstream of lmbA. The proteins LmbB1 (mol. mass, 18 kDa) and LmbB2 (mol. mass 34 kDa), when over-produced together in Escherichia coli, brought about enzyme activities for the specific conversion of both L-tyrosine and L-3,4-dihydroxyphenylalanine (L-DOPA) to a yellow-colored product. The LmbB1 protein alone catalyzed the conversion of L-DOPA, but not of L-tyrosine. The purified LmbB1 protein showed a Km for L-DOPA of 258.3 microM. The L-tyrosine converting activity could not been demonstrated in vitro. The preliminary interpretation of these data suggests that the protein LmbB1 is an L-DOPA extradiol-cleaving 2,3-dioxygenase and that the protein LmbB2, either alone or in accord with LmbB1, represents an L-tyrosine 3-hydroxylase. This sequence of putative oxidation reactions on L-tyrosine seems to represent a new pathway different from the ones catalyzed by mammalian L-tyrosine hydroxylases or the wide-spread tyrosinases. The protein LmbA seemed not to be involved in this process. The labile, yellow-colored product from L-DOPA could not be converted to a picolinic acid derivative [3-(2-carboxy-5-pyridyl)alanine] in the presence of ammonia. Therefore, it probably is not a derivative of a cis, cis-3-hydroxymuconic acid semialdehyde; instead, its speculative structure represents a heterocyclic precursor of the propylhygric acid moiety of lincomycin A.

Amino Acid Sequence↗
PubMed1998

Radiological and orthopedic score in pediatric hemophilic patients with early and late prophylaxis.

In order to evaluate joint alteration, 17 patients with hemophilia A and B were investigated over a period of 4 years (1993-1997). Patients were subdivided into two groups, according to therapy regimens. In group 1 (n=10) prophylactic treatment was initiated until the third year of life. In group 2 (n=7) patients received prophylactic treatment at the age of 5 years and above. To assess alterations in knee, elbow, and ankle joints, the radiological score and the physical examination score of the Orthopedic Advisory Committee of the World Federation of Hemophilia were used. The sum of the scores of these six joints was defined as the patient-dependent score. Patients of group 1 (median age at the end of observation: 10 years) reached a median radiological score of 1.0 (range: 0-13) and an orthopedic score of 0 (range: 0-4), whereas patients of group 2 (median age: 14 years) had a radiological score of 20 (range: 2-47) and an orthopedic score of 8 (range: 0-12), which shows a significant difference (p <0.01). In both treatment groups a manifestation or progression of arthropathic alteration was seen in those children who had repeated joint bleeding (>5) prior to the onset of prophylactic treatment (r=0.90, p>0.01). Altogether, two of 60 joints in group 1 and 12 of 42 joints in group 2 had a radiological score > or = 4. Elbow joints were more often affected than knee and ankle joints. In conclusion, the number of joint bleedings before prophylactic treatment was started influenced the progression of arthropathy even in patients with early onset of prophylaxis. The aim of treatment in severe hemophilia should be early prophylaxis before repeated joint bleeding occurs in order to prevent osteoarthropathic alteration.

Adolescent↗
PubMed1998

Granulocytes in the subarachnoid space of humans and rabbits with bacterial meningitis undergo apoptosis and are eliminated by macrophages.

The contribution of leukocyte apoptosis to the resolution of meningeal inflammation in bacterial meningitis was studied in the cerebrospinal fluid (CSF) and in meningeal infiltrates of humans and rabbits by in situ tailing, flow cytometry, agarose gel electrophoresis, and electron microscopy. In humans, the rate of apoptotic granulocytes was 21.0+/-20.8% (n=11) in cytocentrifuge preparations and 3.3+/-3.4 (n=14) in putrid infiltrates of autopsy cases (P=0.02). In rabbits, CSF pleocytosis peaked 8 h after the initiation of antibiotic treatment (5311+/-3122/microl). At this time, the rate of apoptotic granulocytes was 15.2+/-7.3% in CSF and 1.8+/-1.4% in the meningeal infiltrates (each group n=6, P=0.007). Thereafter, the rate of apoptotic granulocytes in CSF declined below 10%. In humans and rabbits, bands representing internucleosomal fragments of approximately 180 base pairs and multiples thereof were documented on agarose gels. Phagocytosis of apoptotic granulocytes by macrophages was visualized by light and electron microscopy. In conclusion, during resolution of subarachnoid space inflammation in bacterial meningitis, a substantial fraction of granulocytes undergoes apoptosis. These granulocytes are removed by phagocytosis by macrophages. Apoptosis is more frequent in granulocytes floating in the CSF than in adherent cells.

Animals↗
PubMed1998

Significance of retinoblastoma and mdm2 gene expression as prognostic markers for soft-tissue sarcoma.

The growth regulatory function of the retinoblastoma protein (RB) can be suppressed by mdm2 via RB/mdm2 interaction by perturbation of the RB suppression of the E2F function. The goal of this study was to examine the clinical value of immunohistochemical (IHC) RB detection and its relationship to mdm2 overexpression in a cohort of 198 adult primary soft-tissue sarcomas (STS). RB overexpression reveals, multivariately, a correlation with survival (RR=1.59, P=0.037) as well as mdm2 positivity (RR=2.32, P=0.0035). Stratification of RB results to mdm2 staining shows a prognostic graduation in four levels. Patients with positivity for both antibodies have the highest risk (RR=3.30, P=0.002) and the poorest prognosis (projected 5-year survival rate, 18.6%); those with negativity for both antibodies show the most favourable prognosis (projected 5-year survival rate, 63.4%). Intermediately, an isolated RB overexpression (projected 5-year survival rate, 46.1%) is more favourable than an isolated mdm2 positivity (projected 5-year survival rate, 33.5%). To sum up, this study proves that RB and mdm2 overexpression have an individual and also an additive effect on prognosis in STS.

Adult↗
PubMed1998

Supernumerary nipples: prevalence, size, sex and side predilection -- a prospective clinical study.

UNLABELLED: The purpose of the following clinical study was to determine the prevalence, size, sex and side predilection of supernumerary nipples. Out of 502 patients, 28 (5.6%) exhibited a supernumerary nipple of small (only areola with diameter less than 30% of normal areola) or middle size (areola with nipple, diameter 30%-50% of normal areola). The male/female ratio was 20/8 and left/right side ratio 15/7 in males and 5/4 in females. CONCLUSION: A supernumerary areola or a supernumerary areola with nipple is a frequent finding. There is a higher prevalence for the left side and male gender.

Adolescent↗
PubMed1998

Neurological outcome in adult patients with early-treated phenylketonuria.

UNLABELLED: Due to the observation of severe neurological symptoms in single patients as well as brain imaging, neuropsychological and neurophysiological abnormalities, the long-term prognosis of treated phenylketonuria is still under discussion. We investigated the neurological outcome of 57 (24 male, 33 female) patients with phenylketonuria (diet onset < 3 months) at a mean age of 23.6 (17-33) years in comparison to control subjects. Methods used were a clinical-neurological examination, tests for fine motor abilities, IQ test (WAIS-R), a neuropsychological attention task and MRI (30 patients only). Tremor was increased in the patients (28%) compared to controls (15%). Fine motor abilities were significantly reduced in three areas: hand-wrist steadiness, finger-hand dexterity and hand-wrist speed. Tremor as well as reduced fine motor skills were not associated with treatment-related variables, e.g. diet onset, strictness of biochemical control or amount of MRI white matter change. IQ was lower in patients (mean 97.6) compared to matched control subjects (mean 105.5). IQ at 12 years was correlated with biochemical control from birth up to the age of 12 and remained stable up to adult age, independent of biochemical control after 12 years of age. In contrast to the other outcome parameters, the performance in a neuropsychological attention task was influenced by the concurrent plasma phenylalanine concentration. Specific late-onset neurological impairment was not identified in this sample of early-treated adults with phenylketonuria. CONCLUSION: Careful neurological investigation revealed subtle symptoms of brain damage even after early-initiated treatment in adult patients with phenylketonuria. At present it cannot be excluded that further neurological deterioration could emerge later in life. Thus, patients with phenylketonuria - either on or off diet - should be monitored throughout life.

Adolescent↗
PubMed1998

A novel type of adhering junction in an epithelioid tumorigenic rat cell culture line.

Two major types of plaque-bearing adhering junctions are commonly distinguished: the actin microfilament-anchoring adhaerens junctions (AJs) and the desmosomes anchoring intermediate-sized filaments (IFs). Both types of junction usually possess the common plaque protein, plakoglobin, whereas the other plaque proteins and the transmembrane cadherins are mutually exclusive. For example, AJs contain E-, N-, or P-cadherin in combination with alpha- and beta-catenin, vinculin and alpha-actinin, whereas in desmosomes, desmogleins and desmocollins are associated with desmoplakin and one or several of the plakophilins (PP1-3). Here we describe a novel type of adhering junction comprising proteins of both AJs and desmosomes and the tight junction (TJ) plaque protein, ZO-1, in a newly established, liver-derived tumorigenic rat cell line (RMEC-1). By immunofluorescence microscopy, cell-cell contacts are characterized by mostly continuous-appearing lines which are usually resolved by electron microscopy as extended arrays of closely spaced small plaque subunits. These plaque-covered regions are positive for plakoglobin, alpha- and beta-catenin, the arm-repeat protein p120, vinculin, desmoplakin and protein ZO-1. They are positive for E-cadherin in cultures early on in passaging, but tend to turn negative for all known cadherins in densely grown cultures. On immunoblotting SDS-PAGE-separated proteins from dense-grown cell monolayers, "pan-cadherin" antibodies have reacted with a band at approximately 140 kDa, identified as N-cadherin by peptide fingerprinting of the immunoprecipitated protein, which for reasons not yet clear is modified or masked in immunolocalization experiments. The exact histological derivation of RMEC-1 cells is not known. However, the observations of several endothelial markers and the fact that all cells are rich in IFs containing vimentin and/or desmin, while only subpopulations also reveal IFs containing CKs 8 and 18, is suggestive of a mesenchymal, probably endothelial origin. We discuss the molecular relationship of this novel type of extended junction with other types of adhering junctions.

Animals↗
PubMed1998

Quinine hydrochloride treatment delays xenoma formation and dissolution in rainbow trout challenged with Loma salmonae.

An experiment was designed to study the effect of dietary quinine hydrochloride (61 mg/kg of fish/day), on the rate of xenoma formation in the gills of Loma salmonae-infected juvenile rainbow trout maintained at a water temperature of 15 degrees C. Almost all (90.9%) control fish had developed xenomas by week 6 post-exposure (PE), but significantly fewer (18.2%) of the medicated fish were similarly affected (P < 0.0001). By week 8 PE, 100% of control fish had xenomas, but only 57.5% of quinine-treated had xenomas (P < 0.0001). However, by week 9 there was no difference between treated and control fish. Xenoma dissolution and branchitis, two crucial events in the pathogenesis of L. salmonae infection in farm-reared Pacific salmon, were present at week 10 in control fish. In contrast, comparable lesions did not develop in treated fish until week 14. These findings are of potential significance for the control of L. salmonae infection in farmed salmon.

Animals↗