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P Sauer

Publications and source records attributed to P Sauer.

At least 19 recordsLinked to original sources
PubMed2006

Prevalence of extended-spectrum beta-lactamase-positive Klebsiella pneumoniae isolates in the Czech Republic.

This study focused on the prevalence and molecular biology of extended-spectrum beta-lactamase (ESBL)-positive Klebsiella pneumoniae isolates collected in the Czech Republic. Clinical material from patients hospitalised in 16 Czech hospitals in September 2004 was used to isolate K. pneumoniae strains. Strains were identified by standard identification procedures. Susceptibility of the strains to antibiotics was tested using a microdilution method. The double-disk synergy test and combination disk method were used to determine ESBL production. Molecular biology characteristics of ESBL-positive isolates were determined using genomic DNA isolation, XbaI restriction digestion and pulsed-field gel electrophoresis differentiation. The acquired restriction maps of individual isolates were compared using GelCompar II software and their relationships were determined. During the 3-week period, 483 K. pneumoniae strains causing clinically detectable diseases were isolated. Of these, 117 (24.2%) were determined to be ESBL-positive. The prevalence of ESBL-positive isolates was 38.9% in Intensive Care Units (ICUs) and 13.1% in standard wards. More than 50% of ESBL-positive isolates were treated effectively only with meropenem (98%), cefoperazone/sulbactam (61%) and amikacin (54%). Conversely, ESBL-negative isolates showed high susceptibility to all tested antibiotics (76-99%). Molecular biology analysis identified 18 clonal types containing two to six identical isolates. Seventeen clones usually contained isolates from only one hospital; isolates from two hospitals were identified only in one clone. Based on the abovementioned results, the prevalence of ESBL-positive K. pneumoniae isolates in the Czech Republic can be perceived as relatively high, especially in ICUs. Extensive spread of 'epidemic clones' within Czech hospitals and, to a limited extent, between them can be demonstrated.

Czech Republic↗
PubMed2006

The role and value of sirolimus administration in kidney and liver transplantation.

Enormous advancements in visceral transplantation have led to significant improvements in the quality of life of patients. However, despite these developments, the average graft half-life after transplantation has remained almost unchanged and chronic rejection is still considered a major problem. In this regard, more concerns have shifted to factors influencing long-term graft survival, patient survival, and quality of life. To achieve this goal, detrimental effects of immunosuppressive (IS) agents, which have deleterious influence on the quality of life and/or patient survival, should be reduced. In the course of recent years, the transplant community has worked on reducing these side effects by developing new ISs, employing new combination regimens, or finding and adjusting optimal dosages and blood level concentrations. Among the IS agents, the antifungal, antitumoral and IS activity of mammalian target of rapamycin (mTOR) inhibitors without nephrotoxicity, have received special attention regarding this new class of IS. Sirolimus (SRL), as the first member of mTOR inhibitors, has been utilized in many clinical trials with respect to its benefit-risk assessment. In our review, the clinical evolution of SRL, as well as the evidence-based clinical benefits of SRL in kidney and liver transplantation (KTx, LTx), are summarized. Various studies of SRL in KTx and LTx have shown that combination therapy with SRL will enrich the variety of IS modalities. It also can be regarded as a safe base therapy to which other necessary drugs can be added. In addition to the enhanced acute rejection prophylaxis, and in contrast to the calcineurin inhibitors (CNI) and steroids, this drug solely does not have common side effects such as nephrotoxicity, neurotoxicity, diabetes mellitus and hypertension. Moreover, this agent might diminish vasculopathic processes that mediate chronic allograft nephropathy (CAN). Therefore, by reducing the likelihood of CAN it can decrease the rate of long-term organ failure. One possibly desirable characteristic of SRL is its antiproliferative effect, which could provoke antitumoral or antiatherogenic activity following transplantation. Despite all promising impacts of SRL in organ transplantation, there are some concerns regarding the adverse effects of this drug, for instance dyslipidemia, pneumonitis and wound healing problems. However, the majority of these side effects can be reduced or ceased by careful dose adjustments and correct timing of use. In conclusion, after a decade of both in vivo and in vitro studies on SRL, it can be advocated that SRL is a promising, potent and effective IS agent as it reduces the rate of acute rejection episodes in de novo transplants. It could improve the quality of life, graft and patient survival rate, and achieve excellent outcomes with few adverse effects when wisely used in combination with other immunosuppressants.

Graft Rejection↗
PubMed2006

Biliary complications after liver transplantation.

Biliary complications remain a substantial cause of morbidity following liver transplantation. They have been reported to occur in a rate of 10-15% of full-size transplantations and may be higher in living donor, split or reduced size liver transplantations. The most common biliary complications following liver transplantations are leaks and strictures. In both, the incidence varies with respect to type of graft and donor as well as the type of biliary anastomosis. The management of the biliary complications requires a multidisciplinary approach and has changed over the past decade, favoring endoscopic and radiological techniques. Surgical revision including retransplantation is reserved for patients in whom endoscopic and interventional modalities are unsuccessful.

Biliary Tract Diseases↗
PubMed2006

Genotypic characterisation of vancomycin-resistant Enterococcus faecium isolates from haemato-oncological patients at Olomouc University Hospital, Czech Republic.

This study describes the first molecular characterisation of clinical isolates of vancomycin-resistant enterococci (VRE) in the Czech Republic. Of 2647 patient isolates of Enterococcus spp. from 1997-2002, 121 (4.6%) were identified as VRE. The most common isolates were VanA+ Enterococcus faecium (78%) and VanB+ Enterococcus faecalis (10%). In addition, five VanA+ E. faecium isolates were obtained from environmental and staff sampling. Macrorestriction analysis of SmaI restriction fragment length polymorphism was performed for 54 VanA+ E. faecium clinical isolates and the five VanA+ E. faecium environmental isolates. Thirty-two unique restriction endonuclease patterns were identified, including two predominant clonal types represented by five or more isolates. Two environmental VanA+ E. faecium isolates were closely related to two patient isolates, which had an identical SmaI macrorestriction pattern. The results indicated potential survival of strains in the hospital environment and possible subsequent transmission to hospitalised patients.

Cancer Care Facilities↗
PubMed2006

[Molecular diagnostics for the detection of prosthetic joint infection].

PURPOSE OF THE STUDY: Ten years after inauguration of the molecular methods into the orthopaedic practice for diagnosing Prosthetic Joint Infection (PJI), this approach is still in the limelight of research and discussion. The aim of the current study was to determine the diagnostic power of our Polymerase Chain Reaction (PCR) protocol for preoperative detection of bacterial nucleic acid in the synovial joint fluid. MATERIAL AND METHODS: Synovial fluids obtained from thirty-five septic hip or knee arthroplasties and sixty-six aseptic controls were investigated by the conventional PCR technique. Two subgroups were established with regard to antibiotic administration before sample collection; with (n=13) and without (n=22) previous antibiotic exposition, respectively. All the surgeries were performed under the identical conditions with strictly established and fulfilled inclusion criteria. The study design applied was a prospective cohort trial. Primers targeting phylogenetically conserved regions of the bacterial gene were used to detect the bacterial 16SrRNA gene in the retrieved samples. If this was positive, a restriction endonuclease treatment of the amplified DNA was performed to reveal the PJI pathogen. Current guidelines were used to evaluate the test performance, including the confidence intervals. The concordance between the culture and PCR identification of PJI pathogens was estimated providing both of the relevant data were available. RESULTS: A qualitative analysis showed the following figures in the subgroup without previous antibiotic exposition: sensitivity (0.64), specificity (0.97), accuracy (0.89), positive predictive value (0.88), negative predictive value (0.89), likelihood ratio for positive result (21.0), and likelihood ratio for negative result (0.38). In the second subgroup the corresponding figures were as follows: 0.85, 0.97, 0.95, 0.85, 0.97, 27.9, and 0.16. The rate of concordance between the microbial and PCR findings was almost identical in both of the subgroups. DISCUSSION: There were large discrepancies in sensitivity and positive predictive values found in the published results. The earlier studies have had various methodological weaknesses, including a lack of strictly formulated inclusion criteria and control groups. In addition, there are differences among research centers in PCR laboratory procedures and specimen retrieval tactics which may potentially have an impact on PCR results. Low sensitivity and high specificity of our PCR technique may be explained by both the intrinsic (DNA extraction protocol, configuration of inner controls, choice of detection threshold, etc.) and extrinsic factors (in particular intra-operative retrieval of specimens). A hypothesis on the inadequacy of PCR techniques for PJI detection still remains to be excluded. CONCLUSION: Based on the current study, the positive results of our PCR technique may be perceived as a mild criterion from the point of power for PJI diagnosis support. However, its clinical utility should be significantly increased in cases with higher pretest probability of PJI, but negative cultures.

Adult↗
PubMed2004

Hematogenous tumor cell dissemination during colonoscopy for colorectal cancer.

BACKGROUND: It has long been suspected that mechanical influences may enhance the release of viable colorectal cancer cells into the circulation. The objective of this study was to determine the extent of hematogenous tumor cell spread in colorectal cancer patients during colonoscopy. METHODS: Peripheral venous blood samples were taken before and after colonoscopy from 44 patients with colorectal cancer. Blood samples were examined using a reverse-transcriptase polymerase chain reaction assay to amplify cytokeratin 20 transcripts. RESULTS: Eleven patients with colorectal cancer displayed circulating tumor cells before and after colonoscopy (25%), whereas tumor cells were detected in six of 44 patients (14%) only after the procedure (p = 0.03, McNemar's test: tumor cell detection before after colonoscopy). All control samples consistently tested negative. CONCLUSIONS: Mechanical forces may result in enhanced release of viable colorectal cancer cells into the circulation; however, the clinical significance of these results needs to be clarified.

Adenocarcinoma↗
PubMed2004

Blood pressure profile and treatment quality in liver allograft recipients-benefit of tacrolimus versus cyclosporine.

Organ transplant recipients display a high cardiovascular mortality rate. The type of immunosuppression has a major impact on cardiovascular risk factors (e.g., hypertension [HTN]). We assessed 24-hour blood pressure (BP) and metabolic profiles in a cohort of 106 long-term liver allograft recipients treated with either tacrolimus (Tac) or cyclosporine (CyA). The median age of patients was 50.8 years (range, 11 to 77) and the median time of follow-up was 65.4 months (ranges 12 to 168). Immunosuppression included low-dose steroids and either Tac (n = 46) or CyA (n = 60). Twenty-four-hour BP measurements revealed a significant difference in systolic BP (127.1 mmHg [94 to 163] Tac versus 132.7 mmHg [103 to 177] CyA; P <.03), and in mean arterial and diastolic blood pressures. In addition, the relative number of normotensive patients was significantly higher among Tac-treated patients (69.6% versus 34.8%). It is of note that the true incidence of HTN was higher after the number of patients with a pathological 24-h BP measurement was added to the initial number of patients already known to have HTN. No less than 76.4% of all long-term liver transplanted patients showed HTN. The results were unrelated to cumulative steroid dosage, frequency of antirejection therapy or underlying primary liver disease. In summary, immunosuppression-induced HTN is more common in CyA-treated than Tac-based regimens. Moreover, we found a substantial lack of detection of HTN in long-term liver transplant patients who received an insufficient quality of antihypertensive treatment. These findings have implications for the early diagnosis and treatment of HTN in liver transplant recipients.

Blood Pressure↗
PubMed2003

Better late than never? Experience with intravenous pamidronate treatment in patients with low bone mass or fractures following cardiac or liver transplantation.

Organ transplantation is associated with a high turnover of bone metabolism, and an increased loss of bone mass and incidence of osteoporotic fractures. Established therapies for osteoporosis after organ transplantation are still lacking, however. We report on an intravenous bisphosphonate therapy initiated in transplant patients because of a high rate of bone loss or incident osteoporotic fractures. Twenty-one patients after liver transplantation and 13 patients after heart transplantation received 30 mg pamidronate intravenously every 3 months, combined with 1000 mg calcium and 1000 IU vitamin D per day. The median time interval between transplantation and start of pamidronate treatment was 1.9 years in cardiac patients and 2.3 years in liver patients. Lumbar spine bone mineral density (LS BMD) and femoral neck BMD (FN BMD) were measured before and every 6 months after pamidronate therapy was initiated. Spinal radiographs were performed annually. Biochemical markers of bone metabolism were determined every 3 months, immediately before pamidronate administration. From a previous observational study, 58 patients treated only with calcium and vitamin D were matched for age, sex, pretransplantation LS BMD and time interval between transplantation and the first pamidronate treatment. In the pamidronate-treated patients, the mean increase in LS BMD adjusted for baseline values amounted to 0.080 +/- 0.038 g/cm(2) (8.6 +/- 4.0 %) after 1 year and 0.091 +/- 0.058 g/cm(2) (10.4 +/- 6.1%) after 2 years compared with 0.001 +/- 0.037 g/cm(2) (0.26 +/- 4.0%) after 1 year and 0.015 +/- 0.057 g/cm(2) (1.8 +/- 6.0%) after 2 years in the historical control group (absolute LS BMD changes pamidronate group vs historical group p < 0.0001 after 1 and 2 years). The changes of FN BMD were 0.024 +/- 0.043 g/cm(2) (3.2 +/- 6.1%) after 1 year and 0.046 +/- 0.052 g/cm(2) (7.0 +/- 6.1%) after 2 years in the pamidronate group compared with -0.012 +/- 0.043 g/cm(2) (-1.6 +/- 6.1%) after 1 year and -0.013 +/- 0.052 g/cm(2) (-1.1 +/- 6.1%) after 2 years in the historical control group (absolute FN BMD changes pamidronate group vs historical group p = 0.003 after 1 year and p = 0.001 after 2 years). From a total of 287 application cycles of pamidronate treatment, no severe side effects were observed and non-severe side effects were seen in only 39 cycles (13.6%). We conclude that cyclic intravenous pamidronate treatment is beneficial to patients with low bone mass or osteoporotic fractures following transplant, even when not immediately initiated.

Adult↗
PubMed2003

Changes in antibiotic resistance in equine bacterial ulcerative keratitis (1991-2000): 65 horses.

OBJECTIVE: To document changes in antibiotic resistance of organisms in cases of equine bacterial ulcerative keratitis over a 10-year time period. DESIGN: A retrospective study. PARTICIPANTS: Medical records of equine patients with bacterial ulcerative keratitis seen at the University of Florida's VMTH for the years 1991-2000 were reviewed. MATERIALS AND METHODS: All cases of equine bacterial ulcerative keratitis for the above mentioned years were examined. Bacterial isolates were identified and subjected to Kirby-Bauer disc diffusion method sensitivity tests. Antibiotics used in the sensitivity tests included bacitracin, ampicillin, gentamicin, chloramphenicol, polymyxin B, trimethoprim-sulfa, neomycin, kanamycin, carbenicillin, tobramycin and enrofloxacin. RESULTS: A total of 65 bacterial isolates were subjected to sensitivity testing. Of these isolates, Pseudomonas aeruginosa accounted for 14 of the bacterial isolates (22%), Streptococcus equi subspecies zooepidemicus accounted for 13 of the bacterial isolates (20%), and Staphylococcus aureus accounted for four of the isolates (6%). A statistically significant increase in resistance of Pseudomonas aeruginosa isolates to the antibiotics gentamicin and tobramycin was found between the isolates from 1992 to 1998 and those from 1999 to 2000. An increase in resistance of Streptococcus equi subspecies zooepidemicus to gentamicin was found between the isolates from 1993 to 1997 and those from 1998 to 2000. CONCLUSIONS: Streptococcus equi subspecies zooepidemicus and Pseudomonas aeruginosa were the most common organisms isolated from cases of equine bacterial keratitis referred to the University of Florida's VMTH for the years 1991-2000. There appears to be an increase in resistance of Streptococcus equi subspecies zooepidemicus to gentamicin over the past 10 years. In addition, there is a significant increase in resistance of Pseudomonas aeruginosa to both gentamicin and tobramycin over the same time period.

Animals↗
PubMed2002

Restoration of liver function and portosystemic pressure gradient after TIPSS and late TIPSS occlusion.

TIPSS (transjugular intrahepatic portosystemic shunt) may be indicated to control bleeding from esophageal and gastric varicose veins, to reduce ascites, and to treat patients with Budd-Chiari syndrome and veno-occlusive disease. Numerous measures to improve the safety and methodology of the procedure have helped to increase the technical and clinical success. Follow-up of TIPSS patients has revealed shunt stenosis to occur more often in patients with preserved liver function (Child A, Child B). In addition, the extent of liver cirrhosis is the main factor that determines prognosis in the long term. Little is known about the effects of TIPSS with respect to portosystemic hemodynamics. This report deals with a cirrhotic patient who stopped drinking 7 months prior to admission. He received TIPSS to control ascites and recurrent esophageal bleeding. Two years later remarkable hypertrophy of the left liver lobe and shunt occlusion was observed. The portosystemic pressure gradient dropped from 24 mmHg before TIPSS to 11 mmHg and remained stable after shunt occlusion. The Child's B cirrhosis prior to TIPSS turned into Child's A cirrhosis and remained stable during the follow-up period of 32 months. This indicates that liver function of TIPSS patients may recover due to hypertrophy of the remaining non-cirrhotic liver tissue. In addition the hepatic hemodynamics may return to normal. In conclusion, TIPSS cannot cure cirrhosis but its progress may be halted if the cause can be removed. This may result in a normal portosystemic gradient, leading consequently to shunt occlusion.

Adult↗
PubMed2002

Intestinal absorption and biliary secretion of ursodeoxycholic acid and its taurine conjugate.

BACKGROUND: Ursodeoxycholic acid (UDCA) and its taurine conjugate (TUDCA) exert a protective effect in cholestatic liver diseases. A greater hepatoprotective effect of TUDCA has been suggested. Absorption appears to be a limiting factor and up to now has not been studied in man. METHODS: We studied absorption and biliary bile acid secretion and composition after administration of UDCA and TUDCA in patients who had complete extrahepatic biliary obstruction caused by pancreatic carcinoma but had no intestinal or liver disease. After 5 days of intact enterohepatic circulation eight patients with a percutaneous biliary-duodenal drainage received, during two study periods, 1000 mg (1916.9 micromol; mean 29.6 micromol kg(-1)) TUDCA and 750 mg (1910.4 micromol; mean 29.5 micromol kg(-1)) UDCA in random order. Each patient served as his own control. RESULTS: After UDCA and TUDCA administration the biliary UDCA content increased to 55.2% and 54.6% of total bile acids, respectively (not significant). Biliary secretion of cholic and chenodeoxycholic acids remained unchanged whereas that of lithocholic acid increased slightly. A total of 64.6% of the orally administered TUDCA and 55.1% of the UDCA was absorbed (not significant). After TUDCA administration, biliary UDCA was preferentially (95.4%) taurine-conjugated whereas after UDCA administration biliary UDCA was mainly (79.8%) glycine-conjugated. CONCLUSIONS: After oral administration of TUDCA and UDCA, no significant differences in their absorption and in biliary bile acid secretion exist. Whether biliary enrichment with taurine conjugates of UDCA instead of glycine conjugates offers advantages in the treatment of cholestatic liver disease is unclear at present.

Aged↗
PubMed2002

Endoscopic variceal ligation plus propranolol vs. transjugular intrahepatic portosystemic stent shunt: a long-term randomized trial.

BACKGROUND AND STUDY AIMS: After a first variceal bleeding episode in patients with cirrhosis of the liver, treatment with transjugular intrahepatic portosystemic stent shunt (TIPS) and endoscopic variceal ligation (EVL) plus propranolol were compared, with regard to prevention of variceal rebleeding, complications, and mortality. PATIENTS AND METHODS: 85 patients were randomly allocated to receive TIPS (n = 43) or EVL (n = 42). The groups were comparable regarding age, sex, etiology of liver cirrhosis, and liver function. RESULTS: The mean observation times were 4.1 years in the TIPS group and 3.6 years in the EVL group. Although the probability of rebleeding was higher in the EVL group (29.9%) than in the TIPS group (19.4%), the difference was not statistically significant. Three of five patients of the EVL group successfully underwent TIPS placement after treatment failure. The probability of TIPS dysfunction requiring shunt revision was 89 %. Hepatic encephalopathy was observed more often in the TIPS group (40.5%) than in the EVL group (20.5%; P < 0.05). The probability of survival was similar in both groups (TIPS group 75.9%, EVL group 82.2%; n.s.). CONCLUSIONS: In view of its good efficacy and the lower cost of treatment, endoscopic ligation plus propranolol may be recommended as initial procedure for prevention of recurrent variceal hemorrhage, whereas TIPS seems to be the preferable procedure in patients with recurrent bleeding after adequate endoscopic and pharmacological treatment.

Adrenergic beta-Antagonists↗
PubMed2001

[Radiologic after-care of transjugular intrahepatic stent shunt (TIPSS)]].

The transjugular intrahepatic stent-shunt (TIPSS) is a well accepted minimal invasive therapy for complications of portal hypertension: recurrent variceal bleeding, refractory ascites and liver failure due to the Budd-Chiari syndrome. The high frequency of shunt stenoses and occlusions makes regular follow up examinations essential. Despite modern non invasive imaging methods direct portography still is the gold standard for shunt surveillance in TIPSS. Ultrasound is helpful to detect shunt dysfunction, but nevertheless its failure rate is considerable despite the use of contrast enhancers such as Levovist because of anatomic and physical limitations, particularly when TIPSS-tracts deep in the liver are present. Reintervention rates approach 90-100% after 24 months, with 100% in child's A patients with comparatively good liver function. However, a strict shunt surveillance program with early portography and reintervention when necessary guarantees high clinical success rates associated with very low rebleeding rates below 10%. Overall the secondary success rate is 80%. Secondary failures are mainly caused by lack of patient compliance during follow-up. In a subgroup of patients no shunt maturation is observed, requiring multiple shunt revisions. In cases of recurrent shunt occlusions an association with bile leaks is presumed. In selected cases patients with chronically recurrent shunt stenosis or occlusions may benefit from placement of TIPSS stent grafts.

Aftercare↗
PubMed2001

Cytokinin oxidase or dehydrogenase? Mechanism of cytokinin degradation in cereals.

An enzyme degrading cytokinins with isoprenoid side chain, previously named cytokinin oxidase, was purified to near homogeneity from wheat and barley grains. New techniques were developed for the enzyme activity assay and staining on native electrophoretic gels to identify the protein. The purified wheat enzyme is a monomer 60 kDa, its N-terminal amino-acid sequence shows similarity to hypothetical cytokinin oxidase genes from Arabidopsis thaliana, but not to the enzyme from maize. N6-isopentenyl-2-(2-hydroxyethylamino)-9-methyladenine is the best substrate from all the cytokinins tested. Interestingly, oxygen was not required and hydrogen peroxide not produced during the catalytic reaction, so the enzyme behaves as a dehydrogenase rather than an oxidase. This was confirmed by the ability of the enzyme to transfer electrons to artificial electron acceptors, such as phenazine methosulfate and 2,6-dichlorophenol-indophenol. 2,3-Dimethoxy-5-methyl-1,4-benzoquinone, a precursor of the naturally occurring electron acceptor ubiquinone, readily interacts with the enzyme in micromolar concentrations. Typical flavoenzyme inhibitors such as acriflavine and diphenyleneiodonium inhibited this enzyme activity. Presence of the flavin cofactor in the enzyme was confirmed by differential pulse polarography and by measuring the fluorescence emission spectrum. Possible existence of a second redox centre is discussed.

Amino Acid Sequence↗
PubMed2000

[Therapy of primary sclerosing cholangitis].

In primary sclerosing cholangitis the aim of treatment is a reduction of the inflammatory destruction of the bile ducts leading to cholestasis and irreversible liver damage. Treatment with ursodeoxycholic acid may decrease the periductular inflammation. Bacterial infection of the bile ducts is frequent and should be treated by antibiotics. Medical treatment of the disease may be successful under the assumption that dominant stenoses are treated endoscopically.

Anti-Bacterial Agents↗