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B Zöllner

Publications and source records attributed to B Zöllner.

At least 19 recordsLinked to original sources
PubMed2005

Prevalence, incidence, and clinical relevance of the reverse transcriptase V207I mutation outside the YMDD motif of the hepatitis B virus polymerase during lamivudine therapy.

The reverse transcriptase V207I mutation within the hepatitis B virus (HBV) polymerase is associated with resistance to lamivudine in vitro. The prevalence of this mutation in treatment-naive patients was 1% (1/96). A follow-up of the patient carrying this mutation prior to treatment revealed no loss of sensitivity of HBV to lamivudine in vivo.

Amino Acid Sequence↗
PubMed2004

Fatal influenza A infection with Staphylococcus aureus superinfection in a 49-year-old woman presenting as sudden death.

A fatal case of influenza A infection with Staphylococcus aureus superinfection in a previously healthy 49-year-old woman presenting as sudden, unexpected death is reported. Autopsy revealed severe necrotizing tracheobronchitis and hemorrhagic pneumonia. Microscopic examination of the trachea and bronchi showed mucosal necrosis and a dense lympho-monocytic infiltration of all layers. The lungs showed focal hemorrhagic pneumonia. No pathological changes were detectable in the myocardium. Influenza A virus was detected in bronchi and lung samples obtained during autopsy by the polymerase chain reaction (PCR) and bacterial superinfection with Staphylococcus aureus was shown by culturing from tracheal, bronchial and pulmonary swabs obtained during autopsy. PCR assays for the detection of Panton-Valentine leukocidin performed from all samples were negative. This case demonstrates the need for an interdisciplinary approach towards an organism-specific diagnosis of potentially infection-related deaths undergoing a medico-legal autopsy. With improved diagnostic possibilities such as PCR and DNA sequencing, forensic pathologists can, in close association with the field of microbiology, make a significant contribution to the detection of highly infectious agents which must be notified to the authorities. This will increase particularly the knowledge about the influence of these agents on sudden, unexpected deaths in outpatients.

Death, Sudden↗
PubMed2002

[Hepatitis C. Virology, transmission modes, clinical aspects, prevention and therapy].

Of the various forms of chronic viral hepatitis, in Germany 60-70% are caused by the hepatitis C virus (HCV). The virus arrives inconspicuously, i.e. an acute infection only leads to an increase in transaminases in 40% of cases and to an increase in bilirubin in only 20%. However, approximately 90% of infections take a chronic course and in 20% this leads to cirrhosis after only 20 years. The infection rate of medical personnel is not significantly higher than in the general population. The transmission of HCV from patients to medical personnel, e.g. by needle stick injuries, is very rare and the risk of infection is less than 1%. Even less frequently transmission of HCV in the reverse direction from medical personnel to patients occurs. An active or passive prophylactic immunization is not possible and protective immunization is not yet foreseeable. Recently, progress has been made with chemotherapeutical treatment of HCV. The present state-of-the-art is pegylated interferon-a in combination with ribavirin. The success rate in HCV genotypes 2 and 3 is clearly higher with 70-80% than in genotypes 1 and 4 with approximately 40%. Both drugs have significant side-effects but better forms of medication are not yet available.

Genotype↗
PubMed2002

Prevalence of SENV-H viraemia among healthy subjects and individuals at risk for parenterally transmitted diseases in Germany.

The prevalence of a newly described DNA virus (SENV-H) was examined in a population of 599 individuals by polymerase chain reaction (PCR). All individuals were assigned to a nonrisk or a risk group depending on the presence of historical or serological factors indicating an increased risk for parenterally transmitted diseases. In a group of 226 healthy blood donors, 38 (16.8%) were found to be SENV-H viraemic. The highest prevalence of SENV-H viraemia was observed among patients infected by HIV (28 of 63; 44.4%). Contrarily, of 78 individuals on maintenance haemodialysis, only 10 (12.8%) were found positive in the SENV-H PCR. Our results demonstrate that SENV-H viraemia is widespread in the general population. Therefore, it seems to be questionable if parenteral transmission is the main route for spreading SENV-H. The hepatitis-inducing capacity of SENV-H is unclear. However, taking our clinical and epidemiological data into account it seems unlikely that this virus is responsible for hepatitis.

Adolescent↗
PubMed2001

20-fold increase in risk of lamivudine resistance in hepatitis B virus subtype adw.

We investigated subtype-dependent development of lamivudine resistance in hepatitis B virus (HBV) longitudinally in 26 consecutive patients (13 adw and 13 ayw carriers) during antiviral treatment of chronic hepatitis B. Lamivudine resistance developed in seven adw carriers and one ayw carrier. Risk of lamivudine resistance was significantly higher for adw carriers than for ayw carriers (p=0.03). We believe that the adw subtype of HBV is associated with a high risk of lamivudine resistance, which might be linked to simultaneous changes of the HBsAg that occurs with the emergence of resistance.

Adult↗
PubMed2001

Strategies for reliable diagnosis of hepatitis C infection: the need for a serological confirmatory assay.

The aim of the study was to examine whether the diagnosis of Hepatitis C (HCV) infection can be obtained reliably without using an immunoblot-based confirmation assay. 1,708 EIA-reactive serum samples were examined retrospectively for (i) optical density value in the screening assay, (ii) reactivity in an immunoblot assay, and (iii) result by RT PCR. In 1,394 (81.0%) samples positive results were obtained by both the HCV EIA and the confirmation assay. OD-values > or = 2.2 were observed in 1026 of these samples, but covered the range from 0.4 to 2.1 in the other 368 samples. The combination of HCV EIA reactivity and indeterminate immunoblot assay was observed in 134 (7.8%) serum samples. HCV RNA was detected in 58 cases by PCR. The OD-values of these 58 samples ranged from 0.4 to >2.2. Especially reactivity against the core recombinant protein was indicative of PCR positivity. The reactivity by the HCV EIA could not be confirmed by immunoblot assay or PCR in 180 (10.5%) sera. These false reactive sera showed OD values by EIA from 0.3 to 2.1. It is concluded that no threshold values can be defined which would allow differentiation between positive, indeterminate, and false reactive result by HCV EIA without producing an unacceptably high number of false negative diagnoses. Not using immunoblot-based confirmation would result in many additional PCR examinations. Therefore, confirmation of reactive HCV EIA results by a serological confirmatory assay must remain an essential part of the diagnostic procedure.

DNA, Viral↗
PubMed2001

Correlation of hepatitis B virus load with loss of e antigen and emerging drug-resistant variants during lamivudine therapy.

It remains unclear whether sequential assessment of hepatitis B virus (HBV) load during lamivudine therapy can predict the loss of hepatitis B e antigen or emergence of drug-resistant variants. Therefore, a longitudinal study was carried out in 28 consecutive patients with chronic hepatitis B who started lamivudine therapy for a median of 12 months (range, 6-31). HBV DNA copy numbers were determined at 3-month intervals. From month 6 onward, HBV viral load below the detection limit of the PCR was predictive of the loss of envelope antigen (P = 0.043). Continuously detectable HBV DNA during the first 12 months of treatment indicated emergence of drug-resistant variants (P = 0.034). These data suggest that the goal of lamivudine therapy should be complete suppression of serum HBV DNA.

Administration, Oral↗
PubMed2001

Application of HIV-1 genotypic-resistance testing prevents the evolution of further resistance mutations in heavily pretreated patients.

BACKGROUND: Resistance-associated mutations in HIV-1 evolve even under highly active antiretroviral therapy. OBJECTIVE: To evaluate the clinical efficacy of genotypic-resistance testing (GRT), to estimate the potential of a given antiretroviral therapy for prevention of further resistance mutations. STUDY DESIGN: Ten patients were treated prospectively with drugs, according to the results of a GRT. Five patients were allocated to group I in which antiretroviral therapy could be switched to an effective regimen (consisting of at least three sensitive drugs, from at least two different classes of antiretroviral substances). Five patients (group II) had no option for effective therapy, and continued to be treated non-effectively (at least one applicated substance class only intermediately sensitive, or resistant). GRT and quantitative viral cultures were performed longitudinally for 8 months. Also, plasma HIV-1 RNA, total CD4+ cells, and rates of productively infected CD4+ cells were determined. RESULTS: All the patients in group I showed a significant decrease of HIV-RNA of >1 log/ml (mean, -1.35 log/ml, P=0.025). The mean increase of CD4+ cells was 46 (not significant). The rate of productively infected CD4+ cells decreased significantly (mean, -16 productively infected CD4+ cells per 10(6) total CD4+ cells, P=0.04). In this group no further resistance mutations were detected after 8 months. In group II, none of the patients showed a significant decrease of HIV-1 RNA (mean, +0.05 log/ml), total CD4+ cells decreased (mean, -35, not significant), the rate of productively infected CD4+ cells increased significantly (mean, +124 productively infected CD4+ cells per 10(6) total CD4+ cells, P=0.04), and 4 of 5 patients had additional mutations in the RT gene conferring multi-drug resistance within 8 months (P=0.048). CONCLUSIONS: GRT is predictive of the efficacy of a therapeutic regimen, in particular regarding evolution of further resistance mutations.

Adult↗
PubMed2001

Comparison of three HCV genotyping assays: a serological method as a reliable and inexpensive alternative to PCR based assays.

BACKGROUND: Determination of hepatitis C virus (HCV) genotypes and subtypes is of rising clinical importance. In times where also an increasing need for cost effectiveness can be observed, the demand for fast and easy performable assays grows. OBJECTIVES: To evaluate and compare different genotyping methods regarding their reliability, practicability, and expense in the daily routine. METHODS: Sera of 39 patients infected with different HCV subtypes were examined by a serological genotyping assay (NS-4 IBA), by the widely used INNO-LiPA HCV II, and by a nucleotide sequencing method. RESULTS: The tests performed equally well in terms of HCV subtyping and no different results were obtained. However, the serotyping assay provided the results in less than half the time needed by the other two assays. Significant differences were also observed regarding the 'hands on' times and the costs. The technical equipment which was necessary to perform the assays is significantly reduced using the serological assay. CONCLUSION: Our study demonstrates that the serological test offers the opportunity to determine HCV genotypes and subtypes reliably, fast, easy, and cost effective.

Genotype↗
PubMed2001

Relevance of reactivity in commercially available hepatitis C virus antibody assays.

Sera from 2,148 patients were tested with a third-generation microparticle enzyme immunoassay (MEIA), a confirmatory assay, and a reverse transcription-PCR. Overall, 85.6% of reactivities were confirmed, 13.2% were shown to be unspecifically reactive, and 1.2% were indeterminate. The rate of confirmed MEIA reactivities clearly depended on the strength of the reactivity.

Adolescent↗
PubMed2001

Prevalence of a novel DNA virus (TTV) among patients on maintenance hemodialysis.

BACKGROUND/AIMS: A recently detected DNA virus (TTV) has been assumed to be responsible for posttransfusion hepatitis in humans. Until now it is unclear whether patients on maintenance hemodialysis are at increased risk of acquiring TTV. METHODS: Serum samples derived from 143 chronically hemodialyzed patients were examined for TTV viremia by nested PCR. All serum specimens were also investigated for viremia and for the presence of antibodies of hepatitis C virus (HCV) and GB virus C/hepatitis G virus (GBV-C/HGV) by PCR and serological assays, respectively. RESULTS: The prevalence of TTV was determined to be 18.8% (n = 27), for HCV a prevalence of 15.4% (n = 22) and for GBV-C/HGV of 8.4% (n = 12) could be demonstrated. Parallel infection by TTV and HCV was detected in only 1.4% (n = 2) of the patients. In no serum sample could TTV and GBV-C/HGV be detected in parallel. None of the solely TTV-viremic individuals had clinical or biochemical signs of liver disease. CONCLUSION: From our data we conclude that TTV viremia is widespread among hemodialysis patients and can be detected in 18.8%. Since no viremic patient had clinical or biochemical signs of liver disease, the hepatitis-inducing capacity of TTV remains unclear.

Adult↗
PubMed2001

Area under the viraemia curve versus absolute viral load: utility for predicting symptomatic cytomegalovirus infections in kidney transplant patients.

A novel approach to predicting symptomatic cytomegalovirus (CMV) infections combines the level and the duration of viraemia in a single parameter. Sixty-four kidney transplant recipients were monitored by quantitative shell vial culture, pp65 antigenaemia, and polymerase chain reaction (PCR) of leucocytes. The area under the curve (AUC) of each parameter was determined from the onset of viraemia to the beginning of antiviral treatment. The AUC values were significantly higher in symptomatic than in asymptomatic patients. For antigenaemia and PCR, optimal AUC thresholds for predicting symptomatic CMV infections were determined. They were superior to standard cutoff levels of absolute viral load in sensitivity, specificity, and positive and negative predictive value. In 8 of the 23 patients who became symptomatic, impending clinical features were indicated earlier by the AUC thresholds than by standard viral load. In conclusion, the concept of the AUC should facilitate identification of patients at risk of symptomatic CMV infection.

Area Under Curve↗
PubMed2000

In vivo dynamics and pathogenicity of wild-type and resistant Hepatitis B virus during long-term lamivudine monotherapy - a clinical note.

BACKGROUND: Genotypic resistance of Hepatitis B virus (HBV) against lamivudine evolves within months after onset of therapy. OBJECTIVES: To determine the longitudinal order in which resistance mutations appear and to compare the kinetics and pathogenicity of wild-type and resistant HBV. STUDY DESIGN: In a longitudinal study, consecutive samples were drawn over a period of 28 months from a patient with chronic hepatitis B, and resistance mutations were followed by sequencing a part of the polymerase region of HBV. These data were compared with HBV copy numbers, HBsAg and ALT levels, and results of consecutive liver biopsies. RESULTS: After 21 weeks of treatment, a silent mutation at codon 528 (CTG to TTG) occurred. Significant genotypic resistance was detectable after 68 weeks, indicated by a substitution of isoleucine for methionine at residue 552 (M552I). Nineteen weeks later, the virus exhibited additional resistance-associated mutations (L528M and I552V). The resulting high-level resistance was reflected by an increase of serum HBV copies of 4.7 log(10). The turnover of wild-type and resistant HBV was 2.6x10(6) and 1.8x10(6) virions/day, respectively. HBsAg and ALT levels were lower within the period when resistant HBV was detectable. During treatment the progress of liver fibrosis was arrested. CONCLUSIONS: The in vivo replicative capacities and dynamics of wild-type and resistant HBV were similar. However, resistant HBV seemed to exhibit reduced pathogenicity.

Base Sequence↗
PubMed2000

[Evaluating form and function of the nose after open rhinoplasty in unilateral lip-maxillopalatal clefts].

Secondary septorhinoplasty in patients with cleft lip and palate (CLP) is performed to improve nasal form and function. The purpose of this study was to compare the initial findings and the surgical outcome in 30 patients with unilateral CLP. Open rhinoplasty was carried out to correct nasal deformity. Nasal soft tissue analysis was done by measurement of standardized raster photographs of the nose and lateral teleradiography. Deviations from the ideal form regarding nasal symmetry, nasal width, and alar base line were determined. The nasal profile was assessed by measuring the nasofacial and nasolabial angle, the angle between the upper lip and the Frankfurt horizontal plane (FHP), and the angle between the columella and the FHP. Nasal patency was evaluated by rhinomanometry. The overall flow (cm3/s) was determined and the flow of the cleft side and non-cleft side compared. Evaluations were made immediately before and 6 months after surgery. In the frontal plane, nasal symmetry was significantly improved and the alar form adjusted. The deep position of the columella was corrected. The acute nasofacial angle and the drooping ala were not significantly improved. An increase in the overall flow and correction of the quotient cleft/non-cleft side was achieved by the surgical procedure. In this study, aesthetically and functionally relevant findings were objectified and can be used for quality control.

Adolescent↗