Highly multimodal structure of high topological charge extreme ultraviolet vortex beams.

Optical beams carrying orbital angular momentum are a very active field of research for their prospective applications, especially at short wavelengths. We consider here such beams produced through high-harmonic generation (HHG) in a rare gas and analyze the characterization of their high-charge vortex structure by an extreme ultraviolet Hartmann wavefront sensor. We show that such HHG beams are generally composed of a set of numerous vortex modes. The sensitivity of the intensity and phase of the HHG beam to the infrared laser aberrations is investigated using a deformable mirror.

Hartmann wavefront sensor characterization of a high charge vortex beam in the extreme ultraviolet spectral range.

We demonstrate for the first time, to the best of our knowledge, the ability of extreme ultraviolet (XUV) Hartmann wavefront sensors to characterize high charge vortex beams produced by high-order harmonic generation up to the order of 25. We also show that phase matched absorption limited high harmonic generation is able to maintain the high charge vortex structure of the XUV beam even in a rather long (1 cm) generation medium.

Liposomal bupivacaine for ultrasound-guided rectus sheath blocks after midline laparotomy.

Optimal pain management after open abdominal surgery is essential but can be difficult to achieve. The effects of inadequate analgesia go beyond the first few postoperative days; severe acute postoperative pain may contribute to the development of chronic postsurgical pain. Thoracic epidural analgesia is a traditional approach to the management of acute pain after open abdominal surgery but has multiple possible contraindications and can be technically challenging. In our hospital, we typically offer ultrasound-guided rectus sheath blocks with catheters when epidural analgesia is not feasible. However, the recent registration of long-acting liposomal bupivacaine in the Netherlands as well as logistical and equipment-related issues have led us to consider liposomal bupivacaine as an alternative to the use of catheters. Here, we present a short case series to describe our first clinical experiences with the use of liposomal bupivacaine in ultrasound-guided rectus sheath blocks after midline laparotomy for three patients in whom epidural insertion was contraindicated.

A reference data base for multilead electrocardiographic computer measurement programs.

In an effort to standardize and evaluate the performance of electrocardiographic computer measurement programs, a 15 lead reference library has been developed based on simultaneously recorded standard 12 lead and orthogonal XYZ lead data. A set of 250 electrocardiograms (ECGs) with selected abnormalities was analyzed by a group of five referee cardiologists and 11 different 12 lead and 6 XYZ computer programs. Attention was focused on the exact determination of the onsets and offsets of P, QRS and T waves. The referees performed their task on highly amplified, selected complexes from the library in a two round process. Median results of the referees coincided best with the median derived from all programs. An analysis of stability proved that the combined program median was a robust reference. However, some individual program results were widely divergent. Paired t tests demonstrated earlier onset for P and QRS (p less than 0.001), as well as later offset for P and T waves in the median 12 lead than in the XYZ results. Significant differences also existed among results obtained by programs analyzing all standard ECG leads at one time, the so-called multilead programs, and those obtained by the conventional standard three lead analysis programs. As a consequence, the derived P, PR, QRS and QT interval measurements varied quite widely among the various programs. Significant differences were also observed among measurements of Q, R and S duration. Some programs showed Q waves that were on the average 6 ms (p less than 0.001) longer than those of others. This may significantly influence diagnostic performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Therapy of focal viral encephalitis in children with aciclovir and recombinant beta-interferon - results of a placebo-controlled multicenter study.

Focal viral encephalitis in childhood is a rare but life-threatening disease. Animal experiments and case reports suggest a positive effect of an additional therapy with interferon-beta on the course of the disease. Therefore, we initiated a prospective, double-blind placebo-controlled study to investigate the benefit of a combination therapy of Aciclovir (ACV) and recombinant interferon-beta (rIFN-beta) in juvenile focal viral encephalitis. - Initial inclusion criterium was suspicion of focal viral encephalitis. Diagnosis was proven by demonstration of characteristic focal lesions in cerebral imaging or virological evidence of HSV in cerebrospinal fluid. Patients were treated with ACV plus rIFN-beta or ACV plus placebo. Neurological outcome was determined 21 days and 3 months after onset of the disease. - Initially 59 patients were enrolled in the study. Encephalitis was proven in 14 patients (7 ACV + rIFN-beta, 7 ACV + placebo). The study groups were balanced in terms of important prognostic criteria. 10 patients (5 ACV + rIFN-beta, 5 ACV + placebo) were cured or had slight defects, 4 patients (2 ACV + rIFN-beta, 2 ACV + placebo) showed moderate to severe defects. There was no significant difference in favour of the additive therapy with rIFN-beta.

Double-differential PCR for gene dosage estimation of erbB oncogenes in benign and cancer tissues and comparison to cellular DNA content.

Competitive and differential quantitative PCR methods circumvent the limiting factors of PCR which cause poor reproducibility. We describe the development and performance evaluation of another quantitative PCR method, double-differential PCR (ddPCR). The ddPCR method comprises the co-amplification of the single-copy gene HBB, the erbB-1, erbB-2 and erbB-3 oncogenes and the second single-copy reference gene SOD2 under equal reaction conditions. The ratio of band intensities of the PCR products in silver-stained polyacrylamide gels expresses the average gene copy number (AGCN) per cell of the erbB oncogenes. The coefficient of variability (CV) was less than 25% for an AGCN of 1. The PCR data were in correlation to the results from dot blotting. DNA image analysis did not reveal any correlation between DNA content and gene dosage deviation of the erbB oncogenes. The method was applied to normal breast tissue, benign breast diseases, breast cancer tissue and lymph node metastases. We suggest this method as being reproducible, low cost and rapid, and therefore suitable for clinical studies on erbB oncogene dosage estimation.

Improvement of rotavirus isolation in the cell culture by immune peroxidase staining.

Peroxidase-labeled monoclonal antibody against rotavirus group-specific antigen (inner capsid) was used for the detection of rotavirus by immunoperoxidase staining (IPS) in trypsin-free MA104 cells within 18 h post-inoculation with clinical specimens. One hundred and twenty-one fecal samples from children with acute gastroenteritis were evaluated by IPS, conventional virus isolation in cell culture and a commercially available group A-antigen ELISA (Rotazyme II, Abbott Laboratories). Fifty-eight (47.9%) stool samples were found positive by IPS. In contrast, rotavirus was isolated from only 4 (3.3%) fecal specimens by conventional cell culture (i.e. demonstration of a cytopathogenic effect). A total of 93 (76.9%) samples were positive by ELISA. IPS permits rapid detection of rotavirus infections and detects shedding of infectious virus. The method should be useful for the investigation of nosocomial spread of rotavirus infection in hospitals, contamination of environmental surfaces and desinfectants.

[Intrathecal interferon therapy in chronic echovirus meningoencephalitis in Bruton type agammaglobulinemia]. / Intrathekale Interferontherapie einer chronischen Echovirusmeningoenzephalitis bei Agammaglobulinämie vom Typ Bruton.

A 9-year-old body with X-linked agammaglobulinemia developed chronic enteroviral meningoencephalitis (CEMA) caused by echovirus type 6. Intravenous treatment with selected immunoglobulin charges containing high titers against echovirus type 6 or combination with beta-interferon did not result in improvement. After implantation of a Rickham reservoir and periodical administration of intraventricular and intravenous immunoglobulin the virus recurred rapidly each time treatment was stopped. After 20 months of treatment the patient received a combined therapy with beta-interferon and selected immunoglobulin. Both drugs were given by lumbar puncture, intravenously and via Rickham reservoir. Subsequently echovirus type 6 could not be isolated in culture or PCR. Cerebrospinal fluid pleocytosis disappeared. The remission is lasting for more than three years. Intrathecal and intraventricular beta-interferon therapy for CEMA is being reported for the first time. Facing the unfavourable prognosis of the disease this mode of treatment is a new therapeutic approach following failure of other therapies.

[The detection of infectious rotaviruses by cell culture technique: use and evaluation of the immunoperoxidase assay]. / Der Nachweis infektiöser Rotaviren mit der Zellkulturtechnik: Einsatz und Bewertung des Immunperoxidase-Assays.

In the present study, virus isolation was attempted in one hundred and twenty-one fecal samples of children suffering from acute gastroenteritis. Virus isolation was performed either conventionally by examination of cytopathogenic effect (CPE) or by immunoperoxidase staining (IPS) of rotavirus group specific antigen (inner capsid) in trypsin free MA104 cells within 18 h. Applying the conventional technique, rotavirus was isolated in only 4 (3.3%) fecal specimens. In contrast, IPS detected infectious virus in 49 (40.5%) stool samples. The specificity of IPS was confirmed by the results obtained with an antigen detection ELISA ("Rotazyme", Abbott, Wiesbaden) and gel electrophoresis of rotaviral RNA (electrophoretyping). ELISA and RNA gel electrophoresis detected rotavirus in 66 (54.4%) and 56 (46.3%) stool samples respectively. IPS enables rapid diagnosis of rotavirus infections in cell cultures applied to detect infectious viral particles in order to be used in the investigation of nosocomial outbreaks, material- and surface contamination and evaluation of disinfectants.

Multicenter evaluation of the novel ABN Western blot (immunoblot) system in comparison with an enzyme-linked immunosorbent assay and a different Western blot.

A new, modular Western blot (immunoblot) system for human immunodeficiency virus (HIV) antibodies (ABN WesPage; Wellcome) was compared with enzyme immunoassays (Wellcome, Behringwerke, and Abbott) and with a U.S. Food and Drug Administration (FDA)-licensed Western blot (DuPont) in a multicenter study. A total of 649 serum samples from HIV patients at different stages of the disease, as well as from high-risk patients, from patients with conditions unrelated to AIDS, and from healthy blood donors, were used in the evaluation along with nine seroconversion panels. For evaluation of Western blot reactivity, both Centers for Disease Control (CDC) and FDA criteria were used. With the DuPont Western blot as the reference assay, the overall sensitivity and specificity of the ABN WesPage were 100 and 99.1%, respectively, when indeterminate results were not taken into account and when both tests were interpreted in accordance with CDC criteria. The DuPont Western blot detected significantly more antibodies to pol and gag gene products than the ABN WesPage. The ABN WesPage showed a higher positive rate of detection of viral envelope band gp160. When both Western blots were interpreted in accordance with CDC criteria, the ABN WesPage and the DuPont Western blot yielded 9.3 and 10.4% indeterminate results, respectively. When the DuPont Western blot was interpreted in accordance with the manufacturer's instructions (FDA criteria), 25.7% of the samples tested were regarded as indeterminate. The choice of interpretation criteria is of paramount importance for the evaluation of HIV Western blot patterns.

Development of a reference library for multi-lead ECG measurement programs.

The development of a data base is described which can be used as common reference for ECG computer programs analyzing 12 or 15 simultaneously recorded leads. This data base is an extension of the 3-lead CSE reference library, described previously.

Establishment of a reference library for evaluating computer ECG measurement programs.

As a result of an international cooperative project entitled "Common Standards for Quantitative Electrocardiography" (CSE), an ECG reference data base has been established with the aim of standardizing computer-derived ECG measurements. The objective of the project is to reduce the wide variation in wave measurements currently obtained by ECG analysis programs. A library of 250 ECGs with selective ECG abnormalities was established and a comprehensive reviewing scheme was devised for the visual determination of the onsets and offsets of P, QRS, and T. This task was performed by a board of cardiologists on highly amplified, selected complexes from the library. A subset was examined in order to study beat-to-beat and intraobserver variability. By using a modified Delphi approach, individual outlying point estimates were eliminated in four successive rounds. In this way final referee estimates were obtained which proved to be highly reproducible and precise. A reference library has thereby been developed which allows testing of the performance of ECG measurement programs and is a useful instrument in establishing recommendations for more precise measurement rules and definitions.