Biomedical subjects

S Schwarz

Publications and source records attributed to S Schwarz.

At least 145 records · Page 8Linked to original sources

PubMed1998

Tetracycline resistance in Staphylococcus spp. from domestic animals.

A total of 838 staphylococcal isolates representing 19 different species were obtained from cattle, cats, dogs, ducks, guinea pigs, horses, mink, pigeons, pigs, rabbits, and turkeys. From these 228 (27.2%) isolates were shown to be resistant to tetracycline and to carry one or two of the tetracycline resistance (tet) genes tet (K), tet (L), tet (M), or tet (O) with seven different distribution patterns. Additional resistances to one or more antibiotics were observed in 153 (67.1%) of the tetracycline resistant isolates. The tet (M) gene was found in 94.3% of the resistant S. intermedius isolates while the tet (K) gene predominated in most of the other staphylococcal species irrespective of the host animal. The tet (K) and tet (L) genes were located on plasmids while the tet (M) and tet (O) genes appeared to be associated with the chromosome.

Animals↗

PubMed1998

Inter- and intra-phage type differentiation of Salmonella enterica subsp. enterica serovar enteritidis isolates using molecular typing methods.

Seventy-six Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) isolates which represented 14 phage types and RDNC isolates were investigated by several independent molecular methods. Eleven different plasmid profiles were detected. Plasmid-encoded virulence genes of the spv gene cluster were shown by hybridization with a spvB/C gene probe to be located on plasmids of either 55 kbp or 95 kbp. Ribotyping as performed with gene probes that recognized either the entire rrn operon or 16S rRNA genes allowed no differentiation between the S. Enteritidis isolates. Three different hybridization patterns could be observed by IS200-typing. Macrorestriction analysis of XbaI-, SpeI- and NotI-digested whole cell DNA proved to be the most discriminatory method as confirmed by the calculation of discriminatory indices. Based on the data obtained from plasmid analysis and macrorestriction analyses with three suitable restriction endonucleases, the 76 S. Enteritidis isolates were assigned to 26 different genomic groups. The observation that several genomic groups included isolates of different phage types has suggested that a combination of suitable molecular methods and phage typing is most useful for tracing S. Enteritidis isolates in epidemiological investigations.

Animals↗

PubMed1998

Approaches to the replacement of ethinylestradiol by natural 17beta-estradiol in combined oral contraceptives.

The strong hepatic estrogenic actions of ethinylestradiol (EE) are very likely to be the cause of the cardiovascular morbidity related to the use of combined oral contraceptives (COCs). This survey presents results of EE replacement in COCs with natural 17beta-estradiol (E2) in the following stages: reduction of EE to daily doses of 0.01 mg and concomitant replacement with E2 (as valerate, EV), complete replacement of EE with E2 using a novel multiphasic combination containing EV and the progestin dienogest (DNG), and the use of natural E2 to develop estrogen sulfamates (J 995) showing sufficient dissociation of uterine from liver estrogenicity. Recent data from preclinical and clinical studies show that these approaches seem to be promising.

Animals↗

PubMed1998

Risk factors and prevention of early infection after implantation or revision of transjugular intrahepatic portosystemic shunts: results of a randomized study.

The aim of this study was to evaluate the efficacy of a single dose of a second-generation cephalosporine to prevent postinterventional infection and to identify risk factors for postinterventional infection in patients receiving implantation or revision of a transjugular intrahepatic portosystemic shunt (TIPS). Eighty-four patients (105 transjugular interventions) were randomized receiving no antibiotic treatment (46 interventions) or 2 g cefotiam (56 interventions) given at the beginning of the procedure. Patients with overt infection or those receiving antibiotic treatment in the preceding two weeks were excluded. Groups were comparable with respect to biographic and medical data. Postinterventional infection was defined as an increase in WBC count (> or =15,000/microl), fever (> or =38.5 degrees C), or a positive blood culture. Infection occurred in 17% of the patients. Patients not receiving cefotiam had a slightly higher incidence of infection (20%) than patients treated with cefotiam (14%, NS). Multivariate analysis demonstrated prognostic relevance for multiple stenting and periprocedural use of a central venous line. The clinical outcome of the patients was unaffected by cefotiam treatment. In conclusion, a single dose of intrainterventional cefotiam does not prevent postinterventional infection. This may be due to the antimicrobial spectrum and short half-time of cefotiam. Strict adherence to aseptic conditions during intervention and early removal of central venous lines may reduce the rate of post interventional infection considerably. Antibiotic prophylaxis with cefotiam does not seem to be useful since it will not influence outcome and costs.

Antibiotic Prophylaxis↗

PubMed1998

Secondary hemorrhage after intraventricular fibrinolysis: a cautionary note: a report of two cases.

OBJECTIVE AND IMPORTANCE: To hasten the lysis of intraventricular hemorrhages, intraventricular administration of recombinant tissue plasminogen activator (rt-PA) or urokinase has been advocated as an effective and safe treatment for patients with intraventricular hemorrhage. Until now, cases of secondary hemorrhage after intraventricular fibrinolysis, to our knowledge, have not been reported in the literature. We present a report of two patients with clinically significant bleeding complications associated with intraventricular infusion of rt-PA. CLINICAL PRESENTATION: Both patients, a 42-year-old woman (Patient 1) and a 70-year-old man (Patient 2), suffered from hypertensive left-sided thalamic hemorrhage with ventricular extension and ventricular dilatation. INTERVENTION: Both patients required external ventricular drainage and were treated with intraventricular rt-PA. In Patient 1, a secondary intraventricular hemorrhage occurred 20 minutes after the first instillation of 2 mg of rt-PA and was associated with a sudden loss of consciousness. Treatment with rt-PA was stopped, and the patient needed a permanent shunt. In Patient 2, intraventricular subsequent bleeding was noted 4 hours after the second 4-mg dose of rt-PA, clinically apparent as anisocoria. In Patient 2, rt-PA administration was continued without further complications. In both patients, a second external ventricular drainage was required after secondary hemorrhage. CONCLUSION: Intraventricular lysis is a potentially hazardous therapy. To weigh the potential benefits against the potential risks, a controlled study of this promising new treatment is urgently warranted.

Adult↗

PubMed1998

Molecular analysis of the macrolide-lincosamide resistance gene region of a novel plasmid from Staphylococcus hyicus.

Resistance to macrolides and lincosamides in Staphylococcus hyicus has been shown to be encoded by a 4.0-kb plasmid designated pSES21. It differed distinctly in its restriction map from all other staphylococcal macrolide resistance plasmids reported so far. Southern blot hybridisation with gene probes specific for staphylococcal erm genes demonstrated that the macrolide resistance gene belonged to hybridisation class C. Analysis of the ermC gene revealed that the deduced amino-acid sequence of the pSES21-encoded ErmC methylase exhibited c. 93% identity with the ErmC methylase encoded by plasmid pE194. The ermC gene of pSES21 was expressed constitutively and sequence analysis of the regulatory region showed multiple base-pair insertions and substitutions in the translational attenuator. As a consequence of these mutations, the reading frame of the small regulatory peptide was destroyed and a novel pair of inverted repeated sequences was generated. Previous studies identified sequence deletions and sequence duplications in the ermC regulatory region as the basis for constitutive ermC gene expression. The multiple point mutations shown in the pSES21-encoded ermC translational attenuator represent a novel kind of structural alteration in this regulatory region and may explain constitutive ermC gene expression by pairing of the newly generated inverted repeated segments in the presence of a functionally deleted reading frame for the small regulatory peptide.

Amino Acid Sequence↗

PubMed1998

Identification and characterization of Arcobacter isolates from broilers by biochemical tests, antimicrobial resistance patterns and plasmid analysis.

A total of 89 Arcobacter butzleri isolates obtained from freshly slaughtered broilers was investigated for their biochemical capacities by using the API CAMPY system as well as additional growth and tolerance tests, for their antimicrobial resistance patterns and their plasmid content. Among these techniques, biochemical profiling and antimicrobial resistance testing proved to be the most discriminatory methods as confirmed by the calculation of discriminatory indices. These two methods might represent valuable tools for epidemiological analysis of A. butzleri isolates. Small plasmids of up to 5 kbp were detectable in only 21 of the 89 isolates while the remaining 68 A. butzleri isolates were plasmid-free.

Abattoirs↗

PubMed1998

Tetracycline resistance in Salmonella enterica subsp. enterica serovar Dublin.

The 47-kbp plasmid pGFT1 from Salmonella enterica subsp. enterica serovar Dublin mediated tetracycline resistance via a tet(A) gene located on an integrated copy of a Tn1721-analogous transposon. The integration site of the transposon was located within the reading frame of a fip gene. Plasmid pGFT1 was shown to be conjugative and to be able to replicate and express tetracycline resistance in Escherichia coli.

DNA Transposable Elements↗

PubMed1998

Tn5706, a transposon-like element from Pasteurella multocida mediating tetracycline resistance.

The 4,378-bp putative tetracycline resistance transposon Tn5706 of Pasteurella multocida consists of an internal tet(H)-tetR resistance gene region which is flanked by almost identical insertion elements, IS1596 and IS1597. Two reading frames for proteins of 70 and 228 amino acids were detected in each of these insertion sequence elements. The 228-amino-acid protein revealed homology to transposase proteins of gram-positive bacteria.

Amino Acid Sequence↗

PubMed1998

Parkinsonism and dystonia in central pontine and extrapontine myelinolysis.

Parkinsonism as well as dystonic signs are rarely seen in central pontine myelinolysis and extrapontine myelinolysis. A 51 year old woman developed central pontine myelinolysis and extrapontine myelinolysis with parkinsonism after severe vomiting which followed alcohol and drug intake, even though marked hyponatraemia had been corrected gradually over six days. Parkinsonism resolved four months after onset, but she then exhibited persistent retrocollis, spasmodic dysphonia, and focal dystonia of her left hand. Although the medical literature documents three similar patients, this patient is different as dystonic symptoms only developed four months after parkinsonian signs had resolved.

Caudate Nucleus↗

PubMed1998

Moderate hypothermia in the treatment of patients with severe middle cerebral artery infarction.

BACKGROUND AND PURPOSE: Animal research and clinical studies in head trauma patients suggest that moderate hypothermia may improve outcome by attenuating the deleterious metabolic processes in neuronal injury. Clinical studies on moderate hypothermia in the treatment of acute ischemic stroke patients are still lacking. METHODS: Moderate hypothermia was induced in 25 patients with severe ischemic stroke in the middle cerebral artery (MCA) territory for therapy of postischemic brain edema. Hypothermia was induced within 14+/-7 hours after stroke onset and achieved by external cooling with cooling blankets, cold infusions, and cold washing. Patients were kept at 33 degreesC body-core temperature for 48 to 72 hours, and intracranial pressure (ICP), cerebral perfusion pressure, and brain temperature were monitored continuously. Outcome at 4 weeks and 3 months after the stroke was analyzed with the Scandinavian Stroke Scale (SSS) and Barthel index. The side effects of induced moderate hypothermia were analyzed. RESULTS: Fourteen patients survived the hemispheric stroke (56%). Neurological outcome according to the SSS score was 29 (range, 25 to 37) 4 weeks after stroke and 38 (range 28 to 48) 3 months after stroke. During hypothermia, elevated ICP values could be significantly reduced. Herniation caused by a secondary rise in ICP after rewarming was the cause of death in all remaining patients. The most frequent complication of moderate hypothermia was pneumonia in 10 of the 25 patients (40%). Other severe side effects of hypothermia could not be detected. CONCLUSIONS: Moderate hypothermia in the treatment of severe cerebral ischemia is not associated with severe side effects. Moderate hypothermia can help to control critically elevated ICP values in severe space-occupying edema after MCA stroke and may improve clinical outcome in these patients.

Adult↗

PubMed1998

Effects of hypertonic saline hydroxyethyl starch solution and mannitol in patients with increased intracranial pressure after stroke.

BACKGROUND AND PURPOSE: The purpose of this study was to prospectively evaluate a protocol with hypertonic saline hydroxyethyl starch (HS-HES) and mannitol in stroke patients with increased intracranial pressure (ICP). METHODS: We studied 30 episodes of ICP crisis in 9 patients. ICP crisis was defined as (1) a rise of ICP of more than 25 mm Hg (n = 22), or (2) pupillary abnormality (n=3), or (3) a combination of both (n=5). Baseline treatment was performed according to a standardized protocol. For initial treatment, the patients were randomly assigned to either infusion of 100 mL HS-HES or 40 g mannitol over 15 minutes. For repeated treatments the 2 substances were alternated. ICP, blood pressure, and cerebral perfusion pressure (CPP) were monitored over 4 hours. Blood gases, hematocrit, blood osmolarity, and sodium were measured before and 15 and 60 minutes after the start of infusion. Treatment was regarded as effective if ICP decreased >10% below baseline value or if the pupillary reaction had normalized. RESULTS: Treatment was effective in all 16 HS-HES-treated and in 10 of 14 mannitol-treated episodes. ICP decreased from baseline values in both groups, P < 0.01. The maximum ICP decrease was 11.4 mm Hg (after 25 minutes) in the HS-HES-treated group and 6.4 mm Hg (after 45 minutes) in the mannitol-treated group. There was no constant effect on CPP in the HS-HES-treated group, whereas CPP rose significantly in the mannitol-treated group. Blood osmolarity rose by 6.2 mmol/L in the mannitol-treated group and by 10.5 mmol/L in the HS-HES-treated group; sodium fell by 3.2 mmol/L in the mannitol and rose by 4.1 mmol/L in the HS-HES-treated group. CONCLUSIONS: Infusion of 40 g mannitol and 100 mL HS-HES decreases increased ICP after stroke. The maximum effect occurs after the end of infusion and is visible over 4 hours. HS-HES seems to lower ICP more effectively but does not increase CPP as much as does mannitol.

Adult↗

PubMed1998

Early hemicraniectomy in patients with complete middle cerebral artery infarction.

BACKGROUND AND PURPOSE: Malignant, space-occupying supratentorial ischemic stroke is characterized by a mortality rate of up to 80%. Several reports indicate a beneficial effect of hemicraniectomy in this situation. However, whether and when decompressive surgery is indicated in these patients is still a matter of debate. METHODS: In an open, prospective trial we performed hemicraniectomy in 63 patients with acute complete middle cerebral artery infarction. Initial clinical presentation was assessed by the Scandinavian Stroke Scale (SSS) and the Glasgow Coma Scale (GCS). All survivors were reexamined 3 months after surgical decompression, with the clinical evaluation graded according to the Rankin Scale (RS) and Barthel Index (BI). We analyzed the influence of early decompressive surgery (<24 hours after symptom onset, based on clinical status at admission and initial CT findings) versus late surgery (>24 hours after first reversible signs of herniation) on mortality, functional outcome, and the length of time of critical care therapy was needed. RESULTS: In total, 46 patients (73%) survived. Despite complete hemispheric infarction, no survivor suffered from complete hemiplegia or was permanently wheelchair bound. In patients with speech-dominant hemispheric infarction (n=11), only mild to moderate aphasia was present. The mean BI score was 65, and RS score revealed severe handicap in 13% of the patients. In 31 patients with early decompressive surgery, mortality was 16% and BI score 68.8. Early hemicraniectomy led to a significant reduction in the length of time critical care therapy was needed (7.4 versus 13.3 days, P<0.05). CONCLUSIONS: In general, the outcome of patients treated with craniectomy in severe ischemic hemispheric infarction was surprisingly good. In addition, early decompressive surgery may further improve outcome in these patients.

Adult↗

PubMed1998

Novel oestrogen sulfamates: a new approach to oral hormone therapy.

Sulfamate substitution at the C-3 position of the steroid skeleton leads to orally active prodrugs of ethinyloestradiol, oestradiol, oestrone, oestriol and probably many other natural or synthetic steroidal oestrogens. These compounds have higher systemic, but reduced hepatic, oestrogenic activity than their parent steroids. The release of the parent oestrogen results from the passage of the sulfamates in the erythrocyte compartment through the liver and the systemic hydrolysis of the sulfamate ester. Sulfamates may be used to generate natural oestrogens, oestradiol and other oestrogens for different types of oral oestrogen therapy, e.g., as oestriol for hindered oestrogen or as 17-alpha oestradiol for 'non-feminising' oestrogen. Oestradiol sulfamate J995 is currently in the initial stages of clinical testing. It has per se no oestrogen receptor affinity or oestrogenic activity in vitro, i.e., is inactive without hydrolysis. Its oral uterotropic activity in rats is approximately 100-times higher than that of oestradiol, its hepatotropic activity, however, is only 2- to 3-fold higher than oestradiol. Oral oestradiol sulfamate treatment should, therefore, reduce the hepatic side-effects seen with conventional oral hormone therapy, while at the same time lead to full stimulation of the uterus and the vagina, and suppression of gonadotropin. In the rat, orally administered oestradiol is effectively extracted from the portal vein and excreted via the bile. In contrast, oestradiol sulfamate is present in the circulation at high concentrations, up to 30% of the dose. Initially, 98% of this is found in the erythrocyte compartment and only 2% in the plasma. Significant oestradiol levels in the blood are recorded during the depletion of this pool. Pharmacokinetic and toxicological studies reveal complete excretion of the compound and its metabolites. No toxic effects have been seen in rats and cynomolgus monkeys at any dose, in spite of the compound's distinct oestrogenicity. The evaluation of genotoxicity also yielded negative results.

Journal Article↗

PubMed1998

Some results of 50 years of research on the resistance to plum pox virus.

Over 300 references on the resistance of stone fruit species to plum pox virus (PPV) have been utilized for the summarization of relevant information in this review. Methods of testing PPV resistance, procedures of evaluation and characterization of PPV resistance as well as breeding of PPV-resistant cultivars are briefly discussed. Altogether 370 cultivars, hybrids and clones of plum, peach, apricot, nectarine and wild Prunus species are tabulated together with the authors who have reported on their immunity, resistance and tolerance.

Fruit↗

PubMed1998

Procalcitonin: a new parameter for the diagnosis of bacterial infection in the peri-operative period.

Procalcitonin, a new innovative inflammation parameter is presently being evaluated in clinical studies. It has been shown to be increased markedly in patients with severe bacteria induced inflammation, septic shock, endotoxinaemia and multiple organ failure. In contrast, severe viral infections or inflammatory reactions of non-infectious origin as well as auto-immune or allergic disorders do not or only very moderately increase procalcitonin serum levels. Because procalcitonin is observed at significantly higher concentrations in bacterial infections, it might assist differentiation between these infections and other aetiologies of critical illnesses. Furthermore, procalcitonin correlates with the severity of infection and sepsis and thus could serve as a useful marker for monitoring surgical high risk patients. Procalcitonin may serve as a valid and sensitive indicator for bacterial infection with important diagnostic potential in the peri-operative period and in intensive care medicine.

Bacterial Infections↗

PubMed1998

Scavestrogen sulfamates: correlation between estrone sulfatase inhibiting and antioxidant effects.

In the present study estrone sulfatase (steryl-sulfatase; EC 3.1.6.2) and phenylsulfatase (arylsulfatase B; EC 3.1.6.1) inhibiting as well as antioxidant effects exerted by ring B,C unsaturated sulfamates of estrone (J 1025), 17 beta-estradiol (J 1054, J 1059, J 1067), and 17 alpha-estradiol (J 1051, J 1064, J 1065) were examined as compared with their parent compounds, J 994, J 995, and J 1050, using six different in vitro models: (i) estrone sulfatase activity in human placental microsomes, (ii) phenylsulfatase activity isolated from Helix pomatia, (iii) Fenton reaction driven lipid peroxidation in rat synaptosomes, (iv) Fe(II)-chelating activities, (v) formation of superoxide anion radicals, and (vi) total antioxidative activities. Ring B,C unsaturated estrogen (so-called scavestrogen) sulfamates were found to act as potent inhibitors of the following enzyme activities and generated radicals: estrone sulfatase, phenylsulfatase, lipid peroxyl, and superoxide anion. In addition, scavestrogen sulfamates were able to influence the iron redox chemistry and total antioxidative activities. These findings indicate that relatively minor modifications in the chemical structure of classical steroid sulfamates can preserve or enhance their estrone sulfatase inhibiting properties and, simultaneously, amplify their antioxidant capacity to a great extent. Taken together, our data suggest that scavestrogen sulfamates such as J 1025, J 1051, or J 1054 (17 beta-dihydroequilenin sulfamate) may serve as a very promising basis for the development of steroid-derived estrone sulfate-sulfatase inhibitors characterized by promising estrone sulfatase inhibiting activities in combination with a "good" antioxidant potency.

Adult↗

PubMed1997

The methylated DNA binding protein-2-H1 (MDBP-2-H1) consists of histone H1 subtypes which are truncated at the C-terminus.

The methylated DNA binding protein-2-H1 (MDBP-2-H1), present in rooster liver, is a member of the histone H1 family which inhibits transcription by binding selectively to methylated promoters. Here we have determined the primary structure of MDBP-2-H1. A comparison between histone H1 and MDBP-2-H1 was achieved by analyzing reversed phase HPLC-purified and V8-digested proteins by mass spectrometry and/or microsequencing. In rooster liver the most abundant histone H1 subtypes are H1 01 and H1 11L. Similarly, MDBP-2-H1 contains the same subtypes of histone H1. The histone H1 subtype H1 01 in MDBP-2-H1 has 150 amino acids, whereas the full-size histone H1 01 is 218 amino acids. The difference in mass between the two proteins is explained by C-terminal truncation of histone H1 01.

Amino Acid Sequence↗