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S Schwarz

Publications and source records attributed to S Schwarz.

At least 37 records · Page 2Linked to original sources
PubMed2004

Phage types, ribotypes and tetracycline resistance genes of Salmonella enterica subsp. enterica serovar Typhimurium strains isolated from different origins in Italy.

The tetracycline resistance (tet) gene patterns of 52 tetracycline resistant Salmonella enterica subsp. enterica (S.) serovar Typhimurium isolates collected from animals, food of animal origin, and humans in Italy, were investigated to evaluate whether the tet gene patterns could be used for strain differentiation in addition to phage typing and ribotyping. The detection of tet genes was performed by specific PCR assays. Ribotyping was performed automatically using PvuII as restriction enzyme. Ten different ribotyping patterns were detected. All isolates were positive for at least one of the tet genes studied and six different tet gene patterns were observed. Ribotyping and tet gene patterns showed discriminatory indices of 0.741 and 0.812, respectively. Multiple tet genes were commonly found among tetracycline resistant S. typhimurium isolates from various sources. The resulting tet gene patterns allowed further discrimination of strains which were otherwise indistinguishable by their phage type, ribotype and origin. Thus, the analysis of tet gene patterns might represent an additional tool for the differentiation of S. typhimurium isolates.

Animals↗
PubMed2004

Direct mass measurements on the superallowed emitter 74Rb and its daughter 74Kr: isospin-symmetry-breaking correction for standard-model tests.

The decay energy of the superallowed beta decay 74Rb(beta+)74Kr was determined by direct Penning trap mass measurements on both the mother and the daughter nuclide using the time-of-flight resonance technique and was found to be Q=10 416.8(4.5) keV. The exotic nuclide 74Rb, with a half-life of only 65 ms, is the shortest-lived nuclide on which a high-precision mass measurement in a Penning trap has been carried out. Together with existing data for the partial half-life as well as theoretical corrections, the decay energy yields a comparative half-life of Ft=3084(15) s for this decay, in agreement with the mean value for the series of the lighter nuclides from 10C to 54Co. Assuming conserved vector current, this result allows for an experimental determination of the isospin-symmetry-breaking correction deltaC.

Journal Article↗
PubMed2004

Does acute occlusion of the carotid T invariably have a poor outcome?

OBJECTIVE: To evaluate the prognosis of patients with acute occlusion of the carotid T. METHODS: The authors studied 42 consecutive patients with acute carotid T occlusion, age 66 (59 to 74) years (median [interquartile range]). T occlusion was diagnosed with transcranial Doppler sonography (TCD; n = 11) and MR (n = 28) or CT (n = 3) angiography. Final infarction size was evaluated on follow-up CT 3 to 7 days after symptom onset and recanalization by follow-up TCD 24 to 36 hours after symptom onset. RESULTS: NIH Stroke Scale (NIHSS) score on admission was 18 (16 to 20). Final infarct size was one-third or less of the middle cerebral artery (MCA) territory in 11, greater than one-third but less than or equal to two-thirds of the MCA territory in 10, and greater than two-thirds of the MCA territory in 21 patients. Modified Rankin Scale (mRS) score 6 months after stroke onset was 2 in 7 (17%), 3 in 2 (5%), 4 in 13 (31%), 5 in 7 (17%), and 6 in 13 (31%) patients. Complete or partial MCA recanalization within 24 hours after symptom onset was observed in 12 of 18 patients treated with thrombolysis and 4 of the remaining 24 patients (p = 0.001) and was associated with better clinical outcome (mRS 2, recanalization 6/7 [86%]; mRS 3 to 5, recanalization 8/22 [36%]; mRS 6, recanalization 2/13 [15%]; p = 0.01). Recanalization and NIHSS score on admission were independent predictors of outcome. CONCLUSIONS: Acute carotid T occlusion does not necessarily carry a poor prognosis. IV thrombolysis frequently results in recanalization, which is related to a better clinical outcome and smaller final infarction size.

Acute Disease↗
PubMed2004

Unambiguous identification of three beta-decaying isomers in 70Cu.

Using resonant laser ionization, beta-decay studies, and for the first time mass measurements, three beta-decaying states have been unambiguously identified in 70Cu. A mass excess of -62 976.1(1.6) keV and a half-life of 44.5(2) s for the (6-) ground state have been determined. The level energies of the (3-) isomer at 101.1(3) keV with T(1/2)=33(2) s and the 1+ isomer at 242.4(3) keV with T(1/2)=6.6(2) s are confirmed by high-precision mass measurements. The low-lying levels of 70Cu populated in the decay of 70Ni and in transfer reactions compare well with large-scale shell-model calculations, and the wave functions appear to be dominated by one proton-one neutron configurations outside the closed Z=28 shell and N=40 subshell. This does not apply to the 1+ state at 1980 keV which exhibits a particular feeding and deexcitation pattern not reproduced by the shell-model calculations.

Journal Article↗
PubMed2004

[Atypical encephalitis in a 20-year-old soldier].

We report a patient with encephalitis who had been diagnosed with an unspecific aetiology. During follow-up, pneumonia was identified due to Mycoplasma pneumoniae infection that could also be confirmed as causal for the brain inflammation. Despite the initially critical clinical situation, the patient's condition improved under specific antibiotic treatment. Pathophysiologic, differential diagnostic, and therapeutic implications are discussed, and guidelines for diagnosis are proposed.

Adult↗
PubMed2004

Escalating immunotherapy of multiple sclerosis--new aspects and practical application.

Recent clinical studies in multiple sclerosis (MS) provide new data on the treatment of clinically isolated syndromes, on secondary progression, on direct comparison of immunomodulatory treatments and on dosing issues. All these studies have important implications for the optimized care of MS patients. The multiple sclerosis therapy consensus group (MSTCG) critically evaluated the available data and provides recommendations for the application of immunoprophylactic therapies. Initiation of treatment after the first relapse may be indicated if there is clear evidence on MRI for subclinical dissemination of disease. Recent trials show that the efficacy of interferon beta treatment is more likely if patients in the secondary progressive phase of the disease still have superimposed bouts or other indicators of inflammatory disease activity than without having them. There are now data available, which suggest a possible dose-effect relation for recombinant beta-interferons. These studies have to be interpreted with caution, as some potentially important issues in the design of these studies (e. g. maintenance of blinding in the clinical part of the study) were not adequately addressed. A meta-analysis of selected interferon trials has been published challenging the value of recombinant IFN beta in MS. The pitfalls of that report are discussed in the present review as are other issues relevant to treatment including the new definition of MS, the problem of treatment failure and the impact of cost-effectiveness analyses. The MSTCG panel recommends that the new diagnostic criteria proposed by McDonald et al. should be applied if immunoprophylactic treatment is being considered. The use of standardized clinical documentation is now generally proposed to facilitate the systematic evaluation of individual patients over time and to allow retrospective evaluations in different patient cohorts. This in turn may help in formulating recommendations for the application of innovative products to patients and to health care providers. Moreover, in long-term treated patients, secondary treatment failure should be identified by pre-planned follow-up examinations, and other treatment options should then be considered.

Clinical Trials as Topic↗
PubMed2004

Vital capacity manoeuvre in general anaesthesia: useful or useless?

As atelectasis occurs in most patients during general anaesthesia and may be one of the major causes for the development of hypoxaemia and nosocomial pneumonia, its prevention may be considered as an important objective in perioperative management. The major causative mechanisms are the loss of respiratory muscle tone, compression and gas absorption. Vital capacity manoeuvres have been proposed as a means to eliminate atelectasis in the vast majority of patients and restore normal pulmonary gas exchange during general anaesthesia. In this review we describe the pathogenesis of atelectasis in the perioperative period and discuss in the light of recent published investigations the suitability of the vital capacity manoeuvre as a tool during general anaesthesia. Reviewing the current literature, a vital capacity manoeuvre during general anaesthesia may only be useful under specific circumstances when mechanical ventilation with a high inspiratory fraction of oxygen is required or during cardiac surgery at the end of cardiopulmonary bypass to reduce the amount of atelectasis and to maintain adequate gas exchange.

Anesthesia, General↗
PubMed2004

[Clinical impact of recruitment maneuvers in patients with acute respiratory distress syndrome].

In patients with acute respiratory distress syndrome (ARDS), recruitment maneuvers have been proposed as an adjunct to mechanical ventilation to open up atelectasis and to keep these alveoli open by the application of adequate high levels of positive end-expiratory pressure (PEEP). Though several studies reported that the responsiveness to recruitment maneuvers resulted in a marked improvement of oxygenation with a concomitant decrease in airway pressure and/or inspiratory fraction of oxygen, the performance of recruitment maneuvers still remains a matter of dispute, especially in patients ventilated with a lung protective ventilation strategy. In this review we discuss the pathophysiological background, factors affecting the responsiveness to recruitment maneuvers and their clinical impact in the light of recently published studies. Successful recruitment depends on several factors like the applied recruitment pressure, the level of PEEP set before and after the recruitment maneuver, the stage and the underlying disease of the ARDS, chest wall mechanics and the transpulmonary pressure as well as the positioning of the patient. Regarding the current literature, recruitment maneuvers may be considered as a rescue therapy in the early stage of severe hypoxemic lung failure, if a lung protective ventilation strategy and other additive adjuncts like prone positioning or the application of inhaled vasodilators failed to induce adequate gas exchange.

Acute Disease↗
PubMed2004

Effects of subinhibitory concentrations of florfenicol on morphology, growth, and viability of Staphylococcus aureus.

Staphylococcus aureus strain Newman was investigated for changes in its growth pattern, its morphology and its viability when grown in the presence of 3 microg/ml florfenicol (Ff). This concentration corresponds to the 0.75-fold strain-specific minimum inhibitory concentration (MIC). Under these conditions, S. aureus Newman showed a distinct retardation in its growth pattern and 20% dead cells were detected in a fluorescence microscopic viability assay. However, bactericidal activity - defined as a 3-log drop in the staphylococcal population - was not recorded at this Ff concentration. Further analysis of the cell wall revealed a significant increase in cell wall thickness of S. aureus Newman when grown in the presence of 3 microg/ml Ff. This might result in a compression of the protoplast with subsequent disruption of single staphylococcal cells. Accordingly, 20% of the staphylococcal cells analysed by electron microscopy proved to be disrupted. These observations suggest that Ff can cause a thickening of the cell wall accompanied by impaired viability of the staphylococcal cells.

Animals↗
PubMed2004

[FISH analysis in the differential diagnosis of flat urothelial lesions using tissue microarrays].

AIMS: FISH technology offers an additional tool in the diagnosis of precancerous and malignant lesions of the urinary tract from cytological specimens. Here, we examined the relevance of chromosomal imbalance in flat urothelial lesions using FISH on paraffin-embedded tissue. In addition, the status of Her2/neu and STK15, a key molecule in the development of aneuploidy, was evaluated. METHODS: Flat lesions (normal urothelium, hyperplasia, reactive atypia, dysplasia and Carcinoma in situlCis) of 73 patients were analyzed in respect of chromosome 3, 7, 17 polysomy, deletion of p16, status of HER2/neu and of STK15 by FISH (UroVysion, PathVysion, Vysis) and immunohistochemistry (HercepTest, DAKO) using tissue microarrays. The data were correlated with histology. RESULTS AND CONCLUSIONS: Aneusomy of at least one of the chromosomes usually correlates with the histology of carcinoma in situ or invasive tumor growth. Reactive atypias, rarely showing chromosomal imbalance, can be distinguished from Cis in the majority of investigated cases, but the FISH technique is not able to differentiate reactive atypia from mild dysplasia. About 30 % of the non-neoplastic lesions like urothelial hyperplasia and normal urothelium display polysomy of at least one chromosome in more than 20% of all cells, indicating an elevated risk towards a synchronous development of a higher dysplastic lesion (i.e. Cis). Polysomy of one of three investigated chromosomes (3, 7, 17) occurs randomly within all lesions. A deletion of the p16 locus is most frequently observed in aneuploid lesions. Altered Her2/neu expression patterns are frequently observed in malignant and dysplastic lesions but also in 25 % of the non-neoplastic lesions. An overexpression of Her2/ neu is found in 10-20% of invasive urothelial carcinomas and occasionally in Cis (5 %). However, the Her2/neu gene locus is not amplified in these samples. Gene amplification of STK15 was seen in tumors as well as in normal urothelium but it is still unclear whether it indicates an elevated risk towards the development of manifest urothelial tumors.

Chromosome Aberrations↗
PubMed2003

Masses of 32Ar and 33Ar for fundamental tests.

Masses of the short-lived radionuclides 32Ar (T(1/2)=98 ms) and 33Ar (T(1/2)=173 ms) have been determined with the Penning trap mass spectrometer ISOLTRAP. Relative uncertainties of 6.0x10(-8) (deltam=1.8 keV) and 1.4x10(-8) (deltam=0.44 keV), respectively, have been achieved. At present, these new mass data serve as the most stringent test of the quadratic form of the isobaric-multiplet mass equation. Furthermore, the improved accuracy for the mass of 32Ar will allow for a better constraint on scalar contributions to the weak interaction. New mass values have also been measured for 44Ar and 45Ar, and a 20sigma deviation for 44Ar from the literature value was found and interpreted.

Journal Article↗
PubMed2003

Lack of association between a single nucleotide polymorphism within the choline acetyltransferase gene and patients with Alzheimer's disease.

Alterations of the cholinergic system may account for typical clinical and pathophysiological disturbances of Alzheimer's disease (AD). In particular, a marked decline of choline acetyltransferase activity (CHAT) and as a consequence of acetylcholine during the course of the disease has been described. Due to the chromosomal localization of CHAT at 10q11.23 and its possible role in the pathophysiology of AD, CHAT may represent an appropriate candidate gene conferring risk to AD. In fact, a recent study identified a functional single nucleotide polymorphism (SNP) within the first common exon of CHAT, which was associated with AD giving an odds ratio of 3.8 (Neurosci. Lett. 333 (2002) 9). Because of the potential importance of this finding we analyzed this SNP and another functional SNP within exon 9 (rs868749) of the CHAT gene using a German case control sample consisting of 242 patients with AD and 143 cognitively healthy controls. No statistically significant differences were obtained for the previously described polymorphism. In addition, the exon 9 SNP (rs868749) was not polymorphic in the studied population. We conclude that the previously identified polymorphism is not associated with AD.

Aged↗
PubMed2003

Optimization of three- and four-color multiparameter DNA analysis in lymphoma specimens.

BACKGROUND: Simultaneous analysis of DNA and immunophenotype of lymphoma cells by flow cytometry allows the calculation of the proliferative activity and aneuploidy in even a small lymphoma population. Unfavorable DNA binding characteristics or spectral features of DNA dyes impair the accuracy of multiparameter DNA analysis and limit their clinical application. We describe here a reliable and reproducible application of both three- and four-color multiparameter DNA analysis. METHODS: After immunostaining of fresh samples of peripheral blood, bone marrow and single cell suspensions of lymph nodes from healthy and lymphoma patients, a methanol fixation for TO-PRO-3 and DRAQ5 staining was tested. RESULTS: The red-excitable TO-PRO-3 on a FACSCalibur is limited to two-color antigen staining including fluorescein-isothiocyanate and phycoerythrin-labeled monoclonal antibodies due to its broad excitation spectrum. Although DRAQ5 is only applicable to flow cytometers equipped with a single argon laser emitting 488-nm light, its emission spectrum can be easily separated from the FITC, PE, and PE/Texas-Red emissions. DRAQ5 showed almost identical stoichiometric DNA binding characteristics as propidium iodide. Coefficient of variation produced by DRAQ5 staining is in the range of 3.5 and is adequate for detecting aneuploid amd near-diploid cells. CONCLUSIONS: These advantageous features of DRAQ5 make it a reliable candidate for multiparameter clinical studies.

Anthraquinones↗
PubMed2003

[Current controversies in the diagnosis and management of cerebral venous and dural sinus thrombosis].

Over the last few years, the results from clinical studies and innovative radiological approaches have significantly altered the management of patients with cerebral venous thrombosis. In contrast to previously held beliefs, cerebral venous thrombosis is considered to be a relatively benign disease with an overall favourable prognosis. Mortality is <10%, and the vast majority of patients recover completely. Although the efficacy of heparin has not been unequivocally proven, it is employed in most centres as the standard therapy. There are not sufficient data supporting long-term anticoagulation. In patients with a proven hypercoagulability syndrome, anticoagulation therapy is generally recommended for a period of 6 months. Whether patients with idiopathic thrombosis should also be treated remains controversial. Non-invasive MR and CT angiography techniques have largely replaced conventional angiography for initial evaluation and follow-up examinations. Both methods have a high sensitivity for cerebral venous thrombosis. Local fibrinolytic therapy or other aggressive recanalizing methods can not be generally recommended.

Anticoagulants↗
PubMed2003

Tetracycline resistance in staphylococci from free-living rodents and insectivores.

One hundred and fifty-eight staphylococcal strains isolated from wild rodents and insectivores were analysed for plasmid-borne resistance to tetracycline (Tc). Only 10 isolates, six Staphylococcus saprophyticus isolates and single isolates of S. xylosus, S. equorum, S. warneri and S. cohnii subsp. cohnii carried a Tc resistance plasmid of approximately 4.4 kb as confirmed by protoplast transformation. All 10 plasmids harboured a Tc resistance gene of hybridization class K [tet(K)] as confirmed by polymerase chain reaction (PCR). The plasmid was assigned to the pT181 family as it revealed a high degree of restriction map homology to pT181 and other members of this family. Macrorestriction analysis with the enzyme SmaI showed that three of the six isolates identified as S. saprophyticus shared the same pulsed-field gel electrophoresis (PFGE) pattern.

Animals↗
PubMed2003

Identification of a truncated Tn1721-like transposon located on a small plasmid of Escherichia coli isolated from Varanus indicus.

The 9.1 kb plasmid pDEWT1 was isolated from an Escherichia coli strain obtained from the faeces of a free-living lizard (Varanus indicus) in Indonesia. This plasmid mediated tetracycline resistance via a tet gene of hybridization class A. Molecular analysis of a 7755 bp segment of plasmid pDEWT1 including the tetR-tet(A) region and its flanking areas suggested that pDEWT1 harboured a truncated copy of the tet(A)-carrying transposon Tn1721 in which the part responsible for chemotaxis and transposition functions was lost. Analysis of the sequences at the integration site revealed the presence of the 5-bp direct repeat TACTT. The sequences upstream and downstream of the integration site showed striking homology to sequences of a non-coding region detectable on a small cryptic plasmid from Yersinia enterocolitica.

Animals↗
PubMed2003

Differentiation of Staphylococcus sciuri strains isolated from free-living rodents and insectivores.

Twenty-nine Staphylococcus sciuri strains isolated from free-living insectivores and rodents were comparatively analysed for their biochemical capacities and their SmaI macrorestriction patterns. The 29 S. sciuri isolates represented 21 different biotypes and 22 different SmaI macrorestriction types. This observation confirmed that S. sciuri isolates obtained from insectivores and rodents living in natural environments constituted a heterogeneous population. Cluster analysis revealed that the macrorestriction patterns and the biochemical profiles matched in some cases. However, S. sciuri isolates that exhibited the same or closely related biochemical profiles were also found to be associated with different macrorestriction patterns. Analysis of the 29 S. sciuri isolates for their plasmid content and their sensitivity to antimicrobial agents showed that most of the isolates were plasmid-free and susceptible to all antimicrobial agents tested.

Animals↗