[Foundations for the scientific use of extensive health care data in Germany-results of the Data Sharing working group of the Medical Informatics Initiative]

Healthcare data are an important resource in applied medical research. They are available multicentrically. However, it remains a challenge to enable standardized data exchange processes between federal states and their individual laws and regulations. The Medical Informatics Initiative (MII) was founded in 2016 to implement processes that enable cross-clinic access to healthcare data in Germany. Several working groups (WGs) have been set up to coordinate standardized data structures (WG Interoperability), patient information and declarations of consent (WG Consent), and regulations on data exchange (WG Data Sharing). Here we present the most important results of the Data Sharing working group, which include agreed terms of use, legal regulations, and data access processes. They are already being implemented by the established Data Integration Centers (DIZ) and Use and Access Committees (UACs). We describe the services that are necessary to provide researchers with standardized data access. They are implemented with the Research Data Portal for Health, among others. Since the pilot phase, the processes of 385 active researchers have been used on this basis, which, as of April 2024, has resulted in 19 registered projects and 31 submitted research applications.

Towards a National Portal for Medical Research Data (FDPG): Vision, Status, and Lessons Learned

Harmonizing medical data sharing frameworks is challenging. Data collection and formats follow local solutions in individual hospitals; thus, interoperability is not guaranteed. The German Medical Informatics Initiative (MII) aims to provide a Germany-wide, federated, large-scale data sharing network. In the last five years, numerous efforts have been successfully completed to implement the regulatory framework and software components for securely interacting with decentralized and centralized data sharing processes. 31 German university hospitals have today established local data integration centers that are connected to the central German Portal for Medical Research Data (FDPG). Here, we present milestones and associated major achievements of various MII working groups and subprojects which led to the current status. Further, we describe major obstacles and the lessons learned during its routine application in the last six months.

Nonlinear pulse compression to 51-W average power GW-class 35-fs pulses at 2-µm wavelength in a gas-filled multi-pass cell

We report on the generation of GW-class peak power, 35-fs pulses at 2-µm wavelength with an average power of 51 W at 300-kHz repetition rate. A compact, krypton-filled Herriott-type cavity employing metallic mirrors is used for spectral broadening. This multi-pass compression stage enables the efficient post compression of the pulses emitted by an ultrafast coherently combined thulium-doped fiber laser system. The presented results demonstrate an excellent preservation of the input beam quality in combination with a power transmission as high as 80%. These results show that multi-pass cell based post-compression is an attractive alternative to nonlinear spectral broadening in fibers, which is commonly employed for thulium-doped and other mid-infrared ultrafast laser systems. Particularly, the average power scalability and the potential to achieve few-cycle pulse durations make this scheme highly attractive.

Aligning Biobanks and Data Integration Centers Efficiently (ABIDE_MI)

ABIDE_MI is a complementary funded 18 months project within the German Medical Informatics Initiative (MII), which aims to align IT infrastructures and regulatory/governance structures between biobanks/biobanking IT and the MII data integration centres (DIC) at German university hospitals. A major task in 2021 was the systematic collection of all documents describing rules, as well as proposal/contract templates for data and biosample use and access at each of the participating 24 university hospitals and their comparison with MII-wide consented data sharing principles, documents and governance structures. This comparison revealed large heterogeneity across the ABIDE_MI sites and further, redundant structures/regulations currently established at the German university hospitals. A second task was the design and stepwise development of an IT network infrastructure with central components (data and biosample query portal) and decentralized standardized FHIR servers to capture the standardized FHIR-based core data set modules (resources) defined within the MII working group "Interoperability". Subsequent steps in the project are the harmonization of the data and biosample sharing governance/regulation frameworks at each ABIDE_MI site, creating synergies for the research infrastructures at the German university hospitals and to link those resources to the German Portal for Medical Research Data and with the BBMRI-ERIC Directory and Negotiator tools.

Bright, high-repetition-rate water window soft X-ray source enabled by nonlinear pulse self-compression in an antiresonant hollow-core fibre

Bright, coherent soft X-ray radiation is essential to a variety of applications in fundamental research and life sciences. To date, a high photon flux in this spectral region can only be delivered by synchrotrons, free-electron lasers or high-order harmonic generation sources, which are driven by kHz-class repetition rate lasers with very high peak powers. Here, we establish a novel route toward powerful and easy-to-use SXR sources by presenting a compact experiment in which nonlinear pulse self-compression to the few-cycle regime is combined with phase-matched high-order harmonic generation in a single, helium-filled antiresonant hollow-core fibre. This enables the first 100 kHz-class repetition rate, table-top soft X-ray source that delivers an application-relevant flux of 2.8 × 10⁶ photon s^-1 eV^-1 around 300 eV. The fibre integration of temporal pulse self-compression (leading to the formation of the necessary strong-field waveforms) and pressure-controlled phase matching will allow compact, high-repetition-rate laser technology, including commercially available systems, to drive simple and cost-effective, coherent high-flux soft X-ray sources.

Watt-scale 50-MHz source of single-cycle waveform-stable pulses in the molecular fingerprint region

We report a coherent mid-infrared (MIR) source with a combination of broad spectral coverage (6-18 μm), high repetition rate (50 MHz), and high average power (0.5 W). The waveform-stable pulses emerge via intrapulse difference-frequency generation (IPDFG) in a GaSe crystal, driven by a 30-W-average-power train of 32-fs pulses spectrally centered at 2 μm, delivered by a fiber-laser system. Electro-optic sampling (EOS) of the waveform-stable MIR waveforms reveals their single-cycle nature, confirming the excellent phase matching both of IPDFG and of EOS with 2-μm pulses in GaSe.

Ultrafast thulium fiber laser system emitting more than 1 kW of average power

In this Letter, we report on the generation of 1060 W average power from an ultrafast thulium-doped fiber chirped pulse amplification system. After compression, the pulse energy of 13.2 μJ with a pulse duration of 265 fs at an 80 MHz pulse repetition rate results in a peak power of 50 MW spectrally centered at 1960 nm. Even though the average heat-load in the fiber core is as high as 98 W/m, we confirm the diffraction-limited beam quality of the compressed output. Furthermore, the evolution of the relative intensity noise with increasing average output power has been measured to verify the absence of transversal mode instabilities. This system represents a new average power record for thulium-doped fiber lasers (1150 W uncompressed) and ultrashort pulse fiber lasers with diffraction-limited beam quality, in general, even considering single-channel ytterbium-doped fiber amplifiers.

High-power frequency comb at 2 μm wavelength emitted by a Tm-doped fiber laser system

We report on the generation of a high-power frequency comb in the 2 μm wavelength regime featuring high amplitude and phase stability with unprecedented laser parameters, combining 60 W of average power with <30  fs pulse duration. The key components of the system are a mode-locked Er:fiber laser, a coherence-preserving nonlinear broadening stage, and a high-power Tm-doped fiber chirped-pulse amplifier with subsequent nonlinear self-compression of the pulses. Phase locking of the system resulted in a phase noise of less than 320 mrad measured within the 10 Hz-30 MHz band and 30 mrad in the band from 10 Hz to 1 MHz.

Thulium-doped nonlinear fiber amplifier delivering 50 fs pulses at 20 W of average power

In this Letter, we present an optimized nonlinear amplification scheme in the 2 μm wavelength region. This laser source delivers 50 fs pulses at an 80 MHz repetition rate with exceptional temporal pulse quality and 20 W of average output power. According to predictions from numerical simulations, it is experimentally confirmed that dispersion management is crucial to prevent the growth of side pulses and an increase of the energy content in a temporal pedestal surrounding the self-compressed pulse. Based on these results, we discuss guidelines to ensure high temporal pulse quality from nonlinear femtosecond fiber amplifiers in the anomalous dispersion regime.

Nonlinear pulse compression to 43 W GW-class few-cycle pulses at 2 μm wavelength

High-average power laser sources delivering intense few-cycle pulses in wavelength regions beyond the near infrared are promising tools for driving the next generation of high-flux strong-field experiments. In this work, we report on nonlinear pulse compression to 34.4 μJ-, 2.1-cycle pulses with 1.4 GW peak power at a central wavelength of 1.82 μm and an average power of 43 W. This performance level was enabled by the combination of a high-repetition-rate ultrafast thulium-doped fiber laser system and a gas-filled antiresonant hollow-core fiber.

Leishmaniasis auf Mallorca: Vorstellung eines ungewöhnlichen Verlaufs unter Immunsuppression

Das spanische Festland und die Balearen sind Endemiegebiete für die kutane und viszerale Leishmaniasis durch Leishmania infantum. Die kutane Leishmaniasis ist die häufigste Verlaufsform.

Der Hauptvektor, die Sandmücke Phlebotomus perniciosus, ist im gesamten Inselgebiet von Mallorca zu finden. Die Leishmaniasis zeichnet sich durch eine Vielzahl von klinischen Erscheinungsbildern aus. Der Immunstatus des Patienten spielt hierbei eine relevante Rolle für den Verlauf der Erkrankung und das Ansprechen der Therapie.

Acceleration of sub-relativistic electrons with an evanescent optical wave at a planar interface

We report on a theoretical and experimental study of the energy transfer between an optical evanescent wave, propagating in vacuum along the planar boundary of a dielectric material, and a beam of sub-relativistic electrons. The evanescent wave is excited via total internal reflection in the dielectric by an infrared (λ = 2 μm) femtosecond laser pulse. By matching the electron propagation velocity to the phase velocity of the evanescent wave, energy modulation of the electron beam is achieved. A maximum energy gain of 800 eV is observed, corresponding to the absorption of more than 1000 photons by one electron. The maximum observed acceleration gradient is 19 ± 2 MeV/m. The striking advantage of this scheme is that a structuring of the acceleration element's surface is not required, enabling the use of materials with high laser damage thresholds that are difficult to nano-structure, such as SiC, Al₂O₃ or CaF₂.

High average power nonlinear compression to 4 GW, sub-50 fs pulses at 2 μm wavelength

The combination of high-repetition-rate ultrafast thulium-doped fiber laser systems and gas-based nonlinear pulse compression in waveguides offers promising opportunities for the development of high-performance few-cycle laser sources at 2 μm wavelength. In this Letter, we report on a nonlinear pulse compression stage delivering 252 μJ, sub-50 fs-pulses at 15.4 W of average power. This performance level was enabled by actively mitigating ultrashort pulse propagation effects induced by the presence of water vapor absorptions.

Thulium-doped fiber chirped-pulse amplification system with 2 GW of peak power

Thulium-doped fibers with ultra large mode-field areas offer new opportunities for the power scaling of mid-IR ultrashort-pulse laser sources. Here, we present a laser system delivering a pulse-peak power of 2 GW and a nearly transform-limited pulse duration of 200 fs in combination with 28.7 W of average power. This performance level has been achieved by optimizing the pulse shape, reducing the overlap with atmospheric absorption lines, and incorporating a climate chamber to reduce the humidity of the atmospheric environment.

Self-compression in a solid fiber to 24 MW peak power with few-cycle pulses at 2 μm wavelength

We report on the experimental realization of a compact, fiber-based, ultrashort-pulse laser system in the 2 μm wavelength region delivering 24 fs pulse duration with 24 MW pulse peak power and 24.6 W average power. This performance level has been enabled by the favorable quadratic wavelength-dependence of the self-focusing limit, which has been experimentally verified to be at approximately 24 MW for circular polarization in a solid-core fused-silica fiber operated at a wavelength around 2 μm. The anomalous dispersion in this wavelength region allows for a simultaneous nonlinear spectral broadening and temporal pulse compression. This makes an additional compression stage redundant and facilitates a very simple and power-scalable approach. Simulations that include both the nonlinear pulse evolution and the transverse optical Kerr effect support the experimental results.

Erratum: Sarcoma of the Uterus. Guideline of the DGGG (S2k-Level, AWMF Registry No. 015/074, August 2015)

[This corrects the article DOI: 10.1055/s-0035-1558120.].

Sarcoma of the Uterus. Guideline of the DGGG (S2k-Level, AWMF Registry No. 015/074, August 2015)

Purpose: Official guideline published and coordinated by the German Society of Gynecology and Obstetrics (DGGG). Due to their rarity and their heterogeneous histopathology uterine sarcomas remain challenging tumors to manage and need a multidisciplinary approach. To our knowledge so far there is no evidence-based guideline on the appropiate management of these heterogeneous tumors. Methods: This S2k-guideline is the work of an representative committee of experts from a variety of different professions who were commissioned by the DGGG to carry out a systematic literature review of uterine sarcoma. Members of the participating scientific societies developed a structured consensus in a formal procedure. Recommendations: 1. The incidence and histopathologic classification of uterine sarcoma. 2. The clinical manifestations, diagnosis and staging of uterine sarcoma. 3. The management of leiomyosarcoma. 4. The management of endometrial stromal sarcoma and undifferentiated uterine sarcoma. 5. The management of adenosarcoma as well as carcinosarcomas. 6. The management of morcellated uterine sarcoma.

What can be learned from optical two-color diffusion and thermodiffusion experiments on ternary fluid mixtures?

A number of optical techniques have been developed during the recent years for the investigation of diffusion and thermodiffusion in ternary fluid mixtures, both on ground and on-board the International Space Station. All these methods are based on the simultaneous measurement of refractive index changes at two different wavelengths. Here, we discuss and compare different techniques with the emphasis on optical beam deflection (OBD), optical digital interferometry, and thermal diffusion forced Rayleigh scattering (TDFRS). We suggest to formally split the data evaluation into a phenomenological parameterization of the measured transients and a subsequent transformation from the refractive index into the concentration space. In all experiments, the transients measured at two different detection wavelengths can be described by four amplitudes and two eigenvalues of the diffusion coefficient matrix. It turns out that these six parameters are subjected to large errors and cannot be determined reliably. Five good quantities, which can be determined with a high accuracy, are the stationary amplitudes, the initial slopes as defined in TDFRS experiments and by application of a heuristic criterion for similar curves, a certain mean diffusion coefficient. These amplitudes and slopes are directly linked to the Soret and thermodiffusion coefficients after transformation with the inverse contrast factor matrix, which is frequently ill-conditioned. Since only five out of six free parameters are reliably determined, including the single mean diffusion coefficient, the determination of the four entries of the diffusion matrix is not possible. We apply our results to new OBD measurements of the symmetric (mass fractions 0.33/0.33/0.33) ternary benchmark mixture n-dodecane/isobutylbenzene/1,2,3,4-tetrahydronaphthalene and existing literature data for the same system.

Nonlinear compression of an ultrashort-pulse thulium-based fiber laser to sub-70 fs in Kagome photonic crystal fiber

Nonlinear pulse compression of ultrashort pulses is an established method for reducing the pulse duration and increasing the pulse peak power beyond the intrinsic limits of a given laser architecture. In this proof-of-principle experiment, we demonstrate nonlinear compression of the pulses emitted by a high-repetition-rate thulium-based fiber CPA system. The initial pulse duration of about 400 fs has been shortened to <70  fs with 19.7 μJ of pulse energy, which corresponds to about 200 MW of pulse peak power.

Coherent combination of two Tm-doped fiber amplifiers

The efficient coherent combination of two ultrafast Tm-doped fiber amplifiers in the 2-μm wavelength region is demonstrated. The performance of the combined amplifiers is compared to the output characteristics of a single amplifier being limited by the onset of detrimental nonlinear effects. Nearly transform-limited pulses with 830-fs duration, 22-μJ pulse energy, and 25-MW peak power have been achieved with a combining efficiency greater than 90%. Based on this result, it can be expected that 2-μm-ultrafast-fiber-laser systems will enter new performance realms in the near future.

Contribution to the benchmark for ternary mixtures: Measurement of the Soret and thermodiffusion coefficients of tetralin+isobutylbenzene+n-dodecane at a composition of (0.8/0.1/0.1) mass fractions by two-color optical beam deflection

Within the framework of an international benchmark test we have performed measurements of the Soret and thermodiffusion coefficients of the organic ternary mixture (0.8/0.1/0.1 mass fraction) of 1,2,3,4-tetrahydronaphthaline (THN), isobutylbenzene (IBB) and n -dodecane (n C12) at 298.15K by means of a two-color optical beam deflection technique (OBD). The data evaluation procedure is based on a least squares fitting routine for an approximate analytical solution for the Soret cell problem. The condition number of the contrast factor matrix and standard error propagation are used for an error estimation for the measured Soret and thermodiffusion coefficients. The Soret coefficients obtained are S (') T(THN) = (1.20±0.09)×10(-3) K^-1, S (') T(IBB) = (- 0.34±0.14)×10(-3) K^-1, and S (') T(nC12) = (- 0.86±0.06)×10(-3) K^-1 and the corresponding thermodiffusion coefficients are D (') T(THN) = (0.72±0.26)×10(-12) m^2(s K)^-1, D (') T(IBB) = (- 0.22±0.42)×10(-12) m^2(s K)^-1, and D (') T(nC12) = (- 0.50±0.16)×10(-12) m^2(s K)^-1. These results will be used as ground-based reference data for the DCMIX project, where thermodiffusion experiments of ternary mixtures are measured in a microgravity environment aboard the International Space Station (ISS).

Benchmark values for the Soret, thermodiffusion and molecular diffusion coefficients of the ternary mixture tetralin+isobutylbenzene+n-dodecane with 0.8-0.1-0.1 mass fraction

With the aim of providing reliable benchmark values, we have measured the Soret, thermodiffusion and molecular diffusion coefficients for the ternary mixture formed by 1,2,3,4-tetrahydronaphthalene, isobutylbenzene and n-dodecane for a mass fraction of 0.8-0.1-0.1 and at a temperature of 25°C. The experimental techniques used by the six participating laboratories are Optical Digital Interferometry, Taylor Dispersion technique, Open Ended Capillary, Optical Beam Deflection, Thermogravitational technique and Sliding Symmetric Tubes technique in ground conditions and Selectable Optical Diagnostic Instrument (SODI) in microgravity conditions. The measurements obtained in the SODI installation have been analyzed independently by four laboratories. Benchmark values are proposed for the thermodiffusion and Soret coefficients and for the eigenvalues of the diffusion matrix in ground conditions, and for Soret coefficients in microgravity conditions.

SAR simulations for high-field MRI: how much detail, effort, and accuracy is needed?

Accurate prediction of specific absorption rate (SAR) for high field MRI is necessary to best exploit its potential and guarantee safe operation. To reduce the effort (time, complexity) of SAR simulations while maintaining robust results, the minimum requirements for the creation (segmentation, labeling) of human models and methods to reduce the time for SAR calculations for 7 Tesla MR-imaging are evaluated. The geometric extent of the model required for realistic head-simulations and the number of tissue types sufficient to form a reliable but simplified model of the human body are studied. Two models (male and female) of the virtual family are analyzed. Additionally, their position within the head-coil is taken into account. Furthermore, the effects of retuning the coils to different load conditions and the influence of a large bore radiofrequency-shield have been examined. The calculation time for SAR simulations in the head can be reduced by 50% without significant error for smaller model extent and simplified tissue structure outside the coil. Likewise, the model generation can be accelerated by reducing the number of tissue types. Local SAR can vary up to 14% due to position alone. This must be considered and sets a limit for SAR prediction accuracy. All these results are comparable between the two body models tested.

Working memory functions in children with different degrees of intellectual disability

BACKGROUND

In recent years, there has been increased research interest in the functioning of working memory in people with intellectual disabilities. Although studies have repeatedly found these individuals to have weak working memory skills, few investigations have distinguished between different degrees of intellectual disability. This study aims to help close this research gap and, in so doing, to examine whether the deficits observed reflect a developmental lag or a qualitative deviation from normal development.

METHOD

In a 5-group design, the working memory performance of a group of 15-year-olds with mild intellectual disability (IQ 50-69) was compared with that of two groups of children (aged 10 and 15 years) with borderline intellectual disability (IQ 70-84) and with that of two groups of children with average intellectual abilities (IQ 90-115) matched for mental and chronological age (aged 7 and 15 years). All children were administered a comprehensive battery of tests assessing the central executive, the visual-spatial sketchpad, and the phonological loop.

RESULTS

The results showed deficits in all three components of working memory, and revealed that these deficits increased with the degree of intellectual disability. The findings indicate that, relative to their mental age peers, children with learning difficulties show structural abnormalities in the phonological store of the phonological loop, but developmental lags in the other two subsystems.

CONCLUSIONS

Similar patterns of results emerged for both subgroups of children with intellectual disability, indicating that problems with phonological information processing seem to be one of the causes of cognitive impairment in individuals with intellectual disability.

A prospective evaluation of the feasibility and utility of additional tools to obtain information from recently diagnosed HIV infected patients

QUESTION UNDER STUDY

Can additional information be obtained from recently HIV diagnosed individuals?

METHODS

A 1-year prospective Swiss study, including all newly diagnosed HIV-infected patients. Information on circumstances of HIV infection was collected through physician- and patient questionnaires and patient interviews. Information on timing of infection was linked with an HIV-antibody avidity assay.

RESULTS

Of 710 newly HIV diagnosed patients, 543 (76%) physician questionnaires (PhyQ) and 145 (20%) patient questionnaires (PaQ) were returned. PhyQ required fewer reminders (57% vs 28% spontaneous return). Patients whose doctors had returned the PhyQ were comparable to total population group. In contrast, a strong bias towards well educated recently infected Swiss men having sex with men (MSM) was seen in patients returning PaQ or agreeing to an interview. 83% of patients claimed that they knew the infection source and 85% infection place. Unprotected sexual contact was the most frequently cited infection source (92%; n = 404). Men mainly claimed occasional (43%) and women steady (61%) partners as the most likely source of HIV infection. Serum for timing of infection was available in 98% of patients. Recent infections (RI) were highest in MSM (51%) and intravenous drug users (IDU, 54%). Compared to women, heterosexual men were more than twice as likely to be diagnosed with a RI.

CONCLUSION

Relevant additional information on circumstances of HIV infection in newly diagnosed patients can easily be collected from treating physicians. Collecting information from patients is not a feasible option, with the exception of qualitative interviews in a selected group of patients.

A prospective evaluation of the feasibility and utility of additional tools to obtain information from recently diagnosed HIV infected patients

QUESTION UNDER STUDY

Can additional information be obtained from recently HIV diagnosed individuals?

METHODS

A 1-year prospective Swiss study, including all newly diagnosed HIV-infected patients. Information on circumstances of HIV infection was collected through physician- and patient questionnaires and patient interviews. Information on timing of infection was linked with an HIV-antibody avidity assay.

RESULTS

Of 710 newly HIV diagnosed patients, 543 (76%) physician questionnaires (PhyQ) and 145 (20%) patient questionnaires (PaQ) were returned. PhyQ required fewer reminders (57% vs 28% spontaneous return). Patients whose doctors had returned the PhyQ were comparable to total population group. In contrast, a strong bias towards well educated recently infected Swiss men having sex with men (MSM) was seen in patients returning PaQ or agreeing to an interview. 83% of patients claimed that they knew the infection source and 85% infection place. Unprotected sexual contact was the most frequently cited infection source (92%; n = 404). Men mainly claimed occasional (43%) and women steady (61%) partners as the most likely source of HIV infection. Serum for timing of infection was available in 98% of patients. Recent infections (RI) were highest in MSM (51%) and intravenous drug users (IDU, 54%). Compared to women, heterosexual men were more than twice as likely to be diagnosed with a RI.

CONCLUSION

Relevant additional information on circumstances of HIV infection in newly diagnosed patients can easily be collected from treating physicians. Collecting information from patients is not a feasible option, with the exception of qualitative interviews in a selected group of patients.

Myosin V stepping mechanism

We observe the myosin V stepping mechanism by traveling wave tracking. This technique, associated with optical tweezers, allows one to follow a scattering particle in a two-dimensional plane, with nanometer accuracy and a temporal resolution in the microsecond range. We have observed that, at the millisecond time scale, the myosin V combines longitudinal and vertical motions during the step. Because at this time scale the steps appear heterogeneous, we deduce their general features by aligning and averaging a large number of them. Our data show that the 36-nm step occurs in three main stages. First, the myosin center of mass moves forward 5 nm; the duration of this short prestep depends on the ATP concentration. Second, the motor performs a fast motion over 23 nm; this motion is associated to a vertical movement of the myosin center of mass, whose distance from the actin filament increases by 6 nm. Third, the myosin head freely diffuses toward the next binding site and the vertical position is recovered. We propose a simple model to describe the step mechanism of the dimeric myosin V.

Analysis of 721 Chlamydia trachomatis-positive urogenital specimens from men and women using lymphogranuloma venereum L2-specific real-time PCR assay

The epidemic of rectal lymphogranuloma venereum among men who have sex with men in western Europe and other parts of the world is ongoing

Die Schweizerische HIV-Kohortenstudie – Ressource für Epidemiologie und Prävention

Die epidemiologische Situation in der Schweiz war gekennzeichnet durch einen deutlichen Rückgang in den Aidsfällen und HIV-assoziierten Todesfällen nach der Einführung der hochaktiven antiretroviralen Therapie (HAART). Die Neuinfektionen haben jedoch in den letzten Jahren wieder zugenommen und die Aidsfälle und Todesfälle nahmen nicht weiter ab. Wir diskutieren beispielhaft drei Fragenkomplexe, die für Epidemiologie und Public Health relevant und aktuell sind: (i) den Gebrauch von SHCS Daten in der Interpretation der Statistiken des Bundesamts für Gesundheit, die auf den Meldungen der Ärzte und Laboratorien beruhen; (ii) Analysen des Zugangs zu und Gebrauch von HAART in verschiedenen Patientengruppen, zum Beispiel Einwanderer, Patienten aus den unteren Sozialschichten und Patienten, die sich durch intravenösen Drogengebrauch mit HIV infiziert hatten; und (iii) die Erfassung von Trends im Sexualverhalten der Studienteilnehmer, inklusive Kondomgebrauch mit stabilen Partnern und bei Gelegenheitskontakten. Anhand dieser Beispiele versuchen wir zu zeigen, dass die SHCS eine wichtige Ressource für die epidemiologische Analyse und Überwachung der Epidemie und die Planung von Public Health Maßnahmen darstellt.

In vivo-application of anti-proctolin-antiserum affects antennal flight posture in crickets

Tethered crickets flying in a wind tunnel adopt a characteristic posture in which the antennae are pointed in parallel and anteriorly into the headwind. Although the firing rates of antennal motoneurons are largely reduced after the start of a flight sequence, the associated postural changes of the antennae are small. It is hypothesised that proctolin, which is present in antennal motoneurons, stabilises the prolonged antennal forward position. To test this hypothesis, proctolin was blocked by anti-proctolin antiserum injections into one antennal base in otherwise intact behaving crickets. The antiserum quickly led to prolonged backward deflections of the treated antennae in 65% of cases. It then took more than one hour for the deflected posture to revert to a normal flight posture. It appears that proctolin is necessary to produce muscle tension large enough to hold the antennae in a forward position and to compensate for the headwind drag. Proctolin, therefore, acts to generate force with reduced electrical activity of motoneurons and muscles.

Physiological characterisation of antennal mechanosensory descending interneurons in an insect (Gryllus bimaculatus, Gryllus campestris) brain

We investigated five different descending brain interneurons with dendritic arborizations in the deutocerebrum in the crickets Gryllus bimaculatus and G. campestris. These interneurones convey specific antennal mechanosensory information to the ventral nerve cord and all responded to forced antennal movements. These interneurones coded for velocity and showed preferences for distinct sectors of the total range of antennal movements. Their axons descended into the posterior connective either ipsilateral or contalateral to the cell body. Electrical stimulation of sensory nerves indicated that the interneurons received input from different afferents of the two antennal base segments. One interneuron had a particularly large axon with a conduction velocity of 4.4ms−1. This was the only one of the five interneurons that also received visual input. Its activity was reduced during voluntary antennal movements. The reduction in activity occurred even after de-efferentation of the antenna, indicating that it had a central origin. Although we do not have experimental evidence for behavioural roles for the descending antennal mechanosensory interneurons, the properties described here suggest an involvement in the perception of objects in the path of the cricket.

Late events in pediatric patients with Ewing sarcoma/primitive neuroectodermal tumor of bone: the Dana-Farber Cancer Institute/Children's Hospital experience

The outcome for 82 pediatric patients with Ewing sarcoma (ES) and primitive neuroectodermal tumor (PNET) of bone is reported; the patients were treated at the Dana-Farber Cancer Institute (DFCI) and Children's Hospital (CH) in Boston, MA (USA) from 1971-1988. The charts of all patients with ES/PNET of bone treated during this period were reviewed for disease status, therapy, sites of relapse, information on second malignancies, and survival status. Eighty-two patients with ES/PNET of bone treated at DFCI/CH were identified. The 10-year event-free survival (EFS) rates were 12% (95% confidence interval [CI] 0, 27%) and 38% (95% CI 26, 51%) for patients with and without metastases, respectively (P = 0.002); the overall survival (OS) rates were 17% (95% CI 1, 33%) and 48% (95% CI 35, 61%) for patients with and without metastases (P = 0.001). Median follow-up for surviving patients is 10.2 years. Primary site in the pelvis also was associated with a poor outcome for patients with no metastatic disease (P = 0.006 OS, P = 0.03 EFS). Thirty-one patients survived in first remission at least 5 years from diagnosis, and of these, five experienced relapse of original disease, and five experienced secondary malignancies. Pediatric patients treated for ES/PNET of bone remain at risk for life-threatening events into the second decade of follow-up. After 5 years, the risk of second malignant neoplasm is at least as high as the risk of late relapse. Prolonged follow-up of patients with ES and PNET of bone is indicated.