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J Breuer

Publications and source records attributed to J Breuer.

At least 55 records · Page 3Linked to original sources
PubMed2001

[Echocardiographic findings before and after interventional occlusion of persistently patent ductus arteriosus with the amplatzer duct occluder].

AIM: The Amplatzer duct occluder(R) is a new system for interventional occlusion of persistently patent ductus arteriosus. The purpose of our study was to determine, whether adequate evaluation of this occluder system can be obtained by echocardiography. METHOD: From 11/1999 until 12/2000, 18 patients were included in the study. All underwent interventional occlusion of a patent ductus arteriosus with the Amplatzer duct occluder(R). Echocardiography was performed on admission, on day one and three and six months following the intervention. RESULTS: The mean age of our patients was 4.8 years (9 months - 18.7 years, median 3.2 years), the mean weight was 18.4 kg (6.5 - 66 kg, median 14 kg). All echocardiographic findings prior to intervention were confirmed during cardiac catheterization. Following intervention we were able to visualize the occluder system and its relation to surrounding structures in all patients. In none of our patients we found an obstruction of the left pulmonary artery. In 1/18 patients there was a minor protrusion of the distal occluder into the descending aorta. Doppler-sonography however revealed no obstruction. Complete occlusion of the ductus arteriosus was confirmed by color Doppler echocardiography in all patients within 5 days, in 17/18 patients no residual shunt was detectable within 24 hours. CONCLUSION: According to our experience the results of interventional occlusion of patent ductus arteriosus in children and adolescents can be well determined by echocardiography.

Adolescent↗
PubMed2001

Interventional occlusion of congenital vascular malformations with the detachable Cook coil system.

INTRODUCTION: Nonsurgical closure of pathologic vascular communications can be achieved by coil embolization. Different systems used in patients with congenital heart disease (e.g., patent ductus arteriosus) allow controlled release of the devices. However, they are too stiff for coil occlusion of small or tortuous vessels. METHODS AND PATIENTS: The new detachable Cook coil system combines flexibility with a simple release control mechanism. Five children, age 8 days to 10 years, underwent heart catheterization for interventional occlusion of different vascular malformations (two coronary artery fistulas, two aortopulmonary collaterals, and one hemangioma). The diameter of the vessels varied between 1.8 mm and 3.6 mm and the length between 10 mm and 22 mm. RESULTS: Up to four 0.018" soft spiral coils were placed as distally as possible in the feeding vessels. In addition, in two patients, one to three J-shaped coils were placed inside and proximal to spiral coils. Positioning of the coils was controlled easily by radio-opaque markers. Counter-clockwise rotation of the delivery wire provided fast and safe detachment without movement of the detached coils. Control angiograms showed complete occlusion of the vessels within 10 minutes after delivery of coils. CONCLUSION: Interventional closure of vascular malformations can be successfully obtained with the detachable Cook coil system. This system offers safe and controlled placement of coils, and it works rapidly in an uncomplicated manner.

Arteriovenous Malformations↗
PubMed2001

Fast acceleration-encoded magnetic resonance imaging.

Direct acceleration imaging with high spatial resolution was implemented and tested. The well-known principle of phase encoding motion components was applied. Suitable gradient switching provides a signal phase shift proportional to the acceleration perpendicular to the slice in the first scan of the sequences. An additional scan serving as a reference was recorded for compensation of phase effects due to magnetic field inhomogeneities. The first scan compensated for phase shifts from undesired first- and second-order motions; the second scan was completely insensitive to velocity and acceleration in all directions. Advantages of the proposed two-step technique compared to former approaches with Fourier acceleration encoding (with several phase encoding steps) are relatively short echo times and short total measuring times. On the other hand, the new approach does not allow us to assess the velocity or acceleration spectrum simultaneously. The capabilities of the sequences were tested on a modern 1.5 T whole body MR unit providing relatively high gradient amplitudes (25 mT/m) and short rise times (600 micros to maximum amplitude). The results from a mechanical acceleration phantom showed a standard deviation of 0.3 m/s2 in sequences with an acceleration range between -12 and 12 m/s2. This range covers the expected maximum acceleration in the human aorta of 10 m/s2. Further tests were performed on a stenosis phantom with a variable volume flow rate to assess the flow characteristics and possible displacement artifacts of the sequences. Preliminary examinations of volunteers demonstrate the potential applicability of the technique in vivo.

Acceleration↗
PubMed2001

Vaccination to prevent varicella and shingles.

Vaccination of healthy children against varicella using the live attenuated Oka vaccine has been available in Japan and south Korea for several years. In 1996, a programme of universal vaccination of children to prevent varicella was introduced in the USA and other countries, including Canada, Germany, and Sweden, have licensed the vaccine for use in healthy children. This article reviews the origin of the Oka vaccine and the evidence for vaccine safety and efficacy in children and adults. Universal vaccination of children and targeted vaccination of groups at risk of severe varicella are discussed. The possible use of the Oka vaccine to prevent zoster is reviewed, and initiatives to develop new varicella zoster virus vaccines are outlined.

Adolescent↗
PubMed2000

CMV viral load measurements in whole blood and plasma--which is best following renal transplantation?

BACKGROUND: Quantitative commercial assays for cytomegalovirus (CMV) detection have recently been developed. Their role in the management of patients after transplantation needs to be evaluated. Widespread use of these assays will allow for comparison of results between centers and meaningful interpretation of the significance of viral load measurements. METHODS: Sequential samples from 52 patients after renal transplantation were tested in the murex hybrid capture assay (HCA) and the Roche Amplicor CMV DNA assay (QPCR) and correlated with the development of CMV disease. A comparison of viral loads in plasma and whole blood was also made. RESULTS: Both assays were sensitive and detected all cases of CMV disease. The specificity and positive predictive value increased from 0.34 and 0.36 to 0.85 and 0.96 for the HCA and 0.37, 0.37 to 0.72 and 0.63 for the QPCR following a receiver operator curve analysis. Higher viral loads were measured using the HCA compared to the QPCR. Response to ganciclovir was associated with a greater than 80% reduction in viral load by HCA or greater than 70% using the QPCR. CONCLUSIONS: Both assays were highly sensitive. By using a receiver operator curve analysis a cutoff viral load can be determined which maximizes the clinical utility of these assays.

Adult↗
PubMed2000

Human papillomavirus infection and non-melanoma skin cancer in immunosuppressed and immunocompetent individuals.

The role of human papillomavirus (HPV) in anogenital carcinogenesis is established firmly, but a similar role in non-melanoma skin cancer remains speculative. Certain immunosuppressed individuals have an increased incidence of both viral warts and non-melanoma skin cancer, that has prompted the suggestion that HPV may play a pathogenic role. Differences in the techniques used to detect HPV DNA in skin, however, have led to discrepancies in the prevalence and spectrum of HPV types reported in these malignancies. This study describes the use of a comprehensive degenerate PCR technique to compare the HPV status of 148 Non-melanoma skin cancers from immunosuppressed and immunocompetent individuals. HPV DNA was detected in 37/44 (84.1%) squamous cell carcinomas, 18/24 (75%) basal cell carcinomas and 15/17 (88.2%) premalignant skin lesions from the immunosuppressed group compared with 6/22 (27.2%) squamous cell carcinomas, 11/30 (36.7%) basal cell carcinomas and 6/11 (54. 4%) premalignancies in the immunocompetent group. Epidermodysplasia verruciformis HPV types prevailed in all lesion types from both groups of patients. In immunosuppressed individuals, cutaneous HPV types were also identified at high frequency, and co-detection of multiple HPV types within single tumours was commonly observed. This study represents the largest and most comprehensive analysis of the HPV status of non-melanoma skin cancers yet undertaken; whereas there are clearly significant differences in non-melanoma skin cancers from immunosuppressed and immunocompetent populations, we provide evidence that the prevalence and spectrum of HPV types does not differ in squamous cell carcinomas, basal cell carcinomas or premalignancies within the two populations. These data have important implications for future investigation of the role of HPV in cutaneous carcinogenesis at a functional level.

Adult↗
PubMed2000

Fish otolith growth in 1g and 3g depends on the gravity vector.

Size and asymmetry (size difference between the left and the right side) as well as calcium (Ca) content of inner ear otoliths of larval cichlid fish Oreochromis mossambicus were determined after a long-term stay at hypergravity conditions (3g; centrifuge). Both utricular and saccular otoliths (lapilli and sagittae, respectively) were significantly smaller after hyper-g exposure as compared to parallely raised 1g-control specimens and the absolute amount of otolith-Ca was diminished. The asymmetry of sagittae was significantly increased in the experimental animals, whereas the respective asymmetry concerning lapilli was markedly decreased. In the course of another experiment larvae were raised in aquarium hatch baskets, from which one was placed directly above aeration equipment which resulted in random water circulation shifting the fish around ("shifted" specimens). The lapillar asymmetry of the "stationary" specimens showed a highly significant increase during early development when larvae were forced to lay on their sides due to their prominent yolk-sacs. In later developmental stages, when they began to swim freely, a dramatic decrease in lapillar asymmetry was apparent. Taken together with own previous findings according to which otolith growth stops after vestibular nerve transaction, the results presented here suggest that the growth and the development of bilateral asymmetry of otoliths is guided by the environmental gravity vector, obviously involving a feedback loop between the brain and the inner ear.

Animals↗
PubMed2000

Management of occupational exposure to hepatitis C: survey of United Kingdom practice.

We conducted a survey to assess the action taken when health care workers suffered inoculation injuries from patients who might have hepatitis C virus (HCV) infection. A substantial proportion of health care workers may be receiving inadequate follow up and existing guidelines should now be implemented in full and extended to include guidance on treatment.

Data Collection↗
PubMed1999

Simultaneous treatment of cytomegalovirus and varicella zoster infections in a renal transplant recipient with ganciclovir: use of viral load to monitor response to treatment.

Disseminated zoster occurring simultaneously with cytomegalovirus (CMV) disease in a renal transplant recipient is potentially life threatening. We describe the use of intravenous ganciclovir to treat both infections. The efficacy of treatment was assessed clinically and by the measurement of CMV viral load using the hybrid capture (Murex version 2) and varicella zoster (VZV) viral load using an in-house assay. Results from this case suggest that clinical resolution in severe viral infections such as described below may be related to early control of viraemia.

Adult↗
PubMed1999

Development of a fluorogenic polymerase chain reaction assay (TaqMan) for the detection and quantitation of varicella zoster virus.

A TaqMan based polymerase chain reaction (PCR) assay was developed for the detection and quantitation of varicella zoster virus (VZV). This method enables simple, reproducible, sensitive and specific detection and quantification of VZV. The TaqMan assay was able to detect four copies of VZV and did not cross-react with other herpesviruses DNA. The assay has several advantages over conventional PCR. First, in the TaqMan assay there is no need for gel electrophoresis and contact with hazardous chemicals. Second, the method is rapid allowing the analysis of 92 samples within minutes after completion of PCR. Finally, the incorporation of a specific probe into the PCR reaction enhances the sensitivity and specificity of the method compared with conventional PCR. The TaqMan system could, therefore, be a useful tool for the epidemiological and diagnostic investigation of VZV.

Adolescent↗
PubMed1999

Flavonol 2,4-dioxygenase from Aspergillus niger DSM 821, a type 2 CuII-containing glycoprotein.

Flavonol 2,4-dioxygenase, which catalyzes the cleavage of quercetin to carbon monoxide and 2-protocatechuoyl-phloroglucinol carboxylic acid, was purified from culture filtrate of Aspergillus niger DSM 821 grown on rutin. It is a glycoprotein (46-54% carbohydrate) with N-linked oligo-mannose type glycan chains. The enzyme was resolved in SDS polyacrylamide gels in a diffuse protein band that corresponded to a molecular mass of 130-170 kDa. When purified flavonol 2,4-dioxygenase was heated, it dissociated into three peptides with apparent molecular masses of 63-67 kDa (L), 53-57 kDa (M), and 31-35 kDa (S), which occurred in a molar ratio of 1:1:1, suggesting a LMS structure. Crosslinking led to a 90-97 kDa species, concomitant with the decrease of staining intensity of the 63-67 kDa (L) and the 31-35 kDa (S) peptides. Analysis by matrix-assisted laser desorption/ionization-time of flight-MS showed peaks at m/z approximately 69 600, m/z approximately 51 700, and m/z approximately 26 500 which are presumed to represent the three peptides of flavonol 2,4-dioxygenase, and a broad peak at m/z approximately 96 300, which might correspond to the LS heterodimer as formed in the crosslinking reaction. Based on the estimated molecular mass of 148 kDa, 1 mol of enzyme contained 1.0-1.6 mol of copper. Ethylxanthate, which specifically reduces CuII to CuI ethylxanthate, is a potent inhibitor of flavonol 2,4-dioxygenase. Metal chelating agents (such as diethyldithiocarbamate, diphenylthiocarbazone) strongly inhibited the enzymatic activity, but inactivation was not accompanied by loss of copper. The EPR spectrum of flavonol 2,4-dioxygenase (as isolated) showed the characteristic parameters of a nonblue type 2 CuII protein. The Cu2+ is assumed to interact with four nitrogen ligands, and the CuII complex has a (distorted) square planar geometry.

Aspergillus niger↗
PubMed1999

Degenerate and nested PCR: a highly sensitive and specific method for detection of human papillomavirus infection in cutaneous warts.

The role of human papillomavirus (HPV) in anogenital carcinogenesis is firmly established, but evidence that supports a similar role in skin remains speculative. Immunosuppressed renal transplant recipients have an increased incidence of viral warts and nonmelanoma skin cancer, and the presence of HPV DNA in these lesions, especially types associated with the condition epidermodysplasia verruciformis (EV), has led to suggestions that HPV may play a pathogenic role. However, differences in the specificities and sensitivities of techniques used to detect HPV in skin have led to wide discrepancies in the spectrum of HPV types reported. We describe a degenerate nested PCR technique with the capacity to detect a broad spectrum of cutaneous, mucosal, and EV HPV types. In a series of 51 warts from 23 renal transplant recipients, this method detected HPV DNA in all lesions, representing a significant improvement over many previously published studies. Cutaneous types were found in 84.3% of warts and EV types were found in 80.4% of warts, whereas mucosal types were detected in 27.4% of warts. In addition, the method allowed codetection of two or more distinct HPV types in 94.1% of lesions. In contrast, single HPV types were detected in all but 1 of 20 warts from 15 immunocompetent individuals. In summary, we have established a highly sensitive and comprehensive degenerate PCR methodology for detection and genotyping of HPV from the skin and have demonstrated a diverse spectrum of multiple HPV types in cutaneous warts from transplant recipients. Studies designed to assess the significance of these findings to cutaneous carcinogenesis are under way.

Base Sequence↗