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Fertilitatsprotektive Masnahmen spielen aufgrund steigender Uberlebensraten bei Krebserkrankungen sowie aufgrund der Fortschritte in der Reproduktionsmedizin zunehmend eine Rolle. Abhangig vom Alter der Patientin, der geplanten onkologischen Therapie und ihrer Dringlichkeit sowie vom Partnerstatus kommen verschiedene Masnahmen infrage, um die Fruchtbarkeit der betroffenen Frau zu erhalten. Ziel dieses Beitrags ist es, einen Uberblick uber die aktuellen Methoden und Ergebnisse der Ovartransposition und Ovartransplantation zu geben. Zudem soll bei den medizinischen Vertrauenspersonen der betroffenen Patientinnen das Bewusstsein fur diese Masnahmen gescharft werden. Sichtung und Diskussion der aktuellen Literatur. Die Ovartransposition vor Radiatio und die autologe Ovartransplantation nach Kryokonservierung sind etablierte fertilitatsprotektive Masnahmen, die betroffenen Patientinnen eine gute Chance bieten, die Fertilitat zu erhalten bzw. wiederherzustellen sowie ihren Kinderwunsch nach einer Krebserkrankung zu erfullen. Die Transposition der Ovarien aus dem Bestrahlungsfeld reduziert das Risiko einer radiogenen Ovarialinsuffizienz. Die Erfolgsrate bezuglich einer erhaltenen Ovarialfunktion liegt laut Literatur bei >80 %. Bei der Kryokonservierung von Ovarialgewebe mit anschliesender Retransplantation konnen Geburtenraten pro Transplantation von etwa 23–30 % erzielt werden. Die operativen Risiken sind bei beiden Verfahren gering. Die Ovartransposition vor Radiatio und die autologe Ovartransplantation nach Kryokonservierung sind wirksame fertilitatsprotektive Masnahmen, die den Patientinnen angeboten werden sollten.

Background Asymptomatic carotid artery stenosis (ACS) has a low risk of stroke. To achieve an advantage over noninterventional best medical treatment (BMT), carotid endarterectomy (CEA) or carotid artery stenting (CAS) must be performed with the lowest possible risk of stroke. Therefore, an analysis of risk-elevating factors is essential. Grade of ipsilateral and contralateral stenosis as well as plaque morphology are known risk factors in ACS. Methods The randomized, controlled, multicenter SPACE-2 trial had to be stopped prematurely after recruiting 513 patients. 203 patients were randomized to CEA, 197 to CAS, and 113 to BMT. Within one year, risk factors such as grade of stenosis and plaque morphology were analyzed. Results Grade of contralateral stenosis (GCS) was higher in patients with any stroke (50%ECST vs. 20%ECST; p=0.012). Echolucent plaque morphology was associated with any stroke on the day of intervention (OR 5.23; p=0.041). In the periprocedural period, any stroke was correlated with GCS in the CEA group (70%ECST vs. 20%ECST; p=0.026) and with echolucent plaque morphology in the CAS group (6% vs. 1%; p=0.048). In multivariate analysis, occlusion of the contralateral carotid artery (CCO) was associated with risk of any stroke (OR 7.00; p=0.006), without heterogeneity between CEA and CAS. Conclusion In patients with asymptomatic carotid artery stenosis, GCS, CCO, as well as echolucent plaque morphology were associated with a higher risk of cerebrovascular events. The risk of stroke in the periprocedural period was increased by GCS in CEA and by echolucent plaque in CAS. Due to small sample size, results must be interpreted carefully.

Hintergrund: Das Manuskript ist eine aktualisierte Version der 2012 entstandenen DGN-Leitlinie zu spontanen Dissektionen der extrakraniellen und intrakraniellen hirnversorgenden Arterien. Ziel der Leitlinie ist, den gegenwartigen Stand des Wissens zur Diagnostik und Therapie anhand der zur Verfugung stehenden wissenschaftlichen Literatur zusammenzufassen und daraus wissenschaftlich begrundete Empfehlungen abzuleiten. Die Leitlinie behandelt ausschlieslich spontane Dissektionen, traumatische Dissektionen werden nicht berucksichtigt. Methodik: Das Leitliniengremium wurde durch Experten der Neurologie gebildet, die eine besondere Expertise in der vaskularen Neurologie besitzen und insbesondere auf dem Gebiet der Dissektion der hirnversorgenden Arterien Forschungsarbeit geleistet haben. Sie wurden von der Deutschen Gesellschaft fur Neurologie bestimmt. Die Vorstande der Deutschen Gesellschaften fur Neuroradiologie, Neurochirurgie und Gefaschirurgie waren an der Formulierung der Leitlinie ebenfalls beteiligt und stimmten dieser zu. Die seit 2012 neu erschienene Literatur wurde von den Autoren gesichtet, und, soweit innovativ und im Hinblick auf die Anzahl der Patienten bedeutsam, in die aktuelle Fassung der Leitlinie eingearbeitet. Die Leitlinie nimmt Stellung zu (1) neuen Erkenntnissen uber die Pathophysiologie der Dissektion (weil diese fur die Auswahl der geeigneten Diagnostik und die Wahl der optimalen Untersuchungszeitpunkte sowie fur das Verstandnis der gewahlten Therapieansatze bedeutsam ist), (2) zur Wertigkeit der verschiedenen diagnostischen Verfahren (insbesondere der extrakraniellen und transkraniellen Farbduplexsonografie, der CT-Angiografie, der MR-Angiografie und spezieller MRT-Techniken zum Nachweis des intramuralen Hamatoms, einschlieslich der Hirnparenchymdiagnostik) und (3) zu den verschiedenen therapeutischen Ansatzen in der Pravention von Insulten. Im therapeutischen Kapitel werden auch interventionelle Therapieansatze bewertet, die aber bei der Dissektion der Zervikalarterien nur eine sehr untergeordnete Rolle spielen. Aufgrund des Fehlens groser randomisierter kontrollierter Studien wurde als Leitlinienstufe der Typ S1 ausgewahlt. Die Regeln der AWMF und der DGN zum Umgang mit potenziellen Interessenkonflikten wurden wahrend des Konsensprozesses gewahrt. Ergebnis: Unter Berucksichtigung der aktuellen wissenschaftlichen Literatur werden konsensusbasierte Empfehlungen mit Erlauterung der Pathophysiologie dieser wenig erforschten Gefaskrankheit und mit Empfehlungen zur klinischen und gestuften bildgebenden Diagnostik, zur fruhen Sekundarpravention mit Thrombozytenfunktionshemmern, Heparin und Antikoagulanzien und zu den Verlaufscharakteristika der Erkrankung sowie der erforderlichen Verlaufsdiagnostik erarbeitet. Die Indikation zu invasiven interventionellen oder zu intensivmedizinischen Masnahmen in speziellen Einzelfallen wurde ebenfalls erortert. Schlussfolgerung: Der Pathophysiologie der Dissektion der hirnversorgenden Arterien liegt eine intramurale Blutung zugrunde. Die duale bildgebende Diagnostik mittels MRT und neurovaskularem Ultraschall ist weiterhin die Diagnostik der ersten Wahl, der Stellenwert der CCT und CTA als reliable Alternative zum MRT hat zugenommen. Die Sekundarprophylaxe von Hirninfarkten oder fluchtigen Insulten sollte primar mit Thrombozytenfunktionshemmern erfolgen, da in den bislang vorliegenden Studien keine Uberlegenheit der Antikoagulation nachgewiesen werden konnte. Als Verlaufsuntersuchung ist der neurovaskulare Ultraschall am besten geeignet. Interventionelle, rekanalisierende Verfahren sind im Einzelfall gerechtfertigt, da positive Fallberichte vorliegen. In seltenen Fallen kann eine mehrtagige Intensivtherapie mit induzierter Hypertonie erforderlich werden.

The attainment of self-propagating fusion burn in an inertial confinement target at the National Ignition Facility will require the use of an ablator with high rocket-efficiency and ablation pressure. The ablation material used during the National Ignition Campaign (Lindl et al. 2014) [1] , a glow-discharge polymer (GDP), does not couple as efficiently as simulations indicated to the multiple-shock inducing radiation drive environment created by laser power profile (Robey et al., 2012). We investigate the performance of two other ablators, boron carbide (B4C) and high-density carbon (HDC) compared to the performance of GDP under the same hohlraum conditions. Ablation performance is determined through measurement of the shock speed produced in planar samples of the ablator material subjected to the identical multiple-shock inducing radiation drive environments that are similar to a generic three-shock ignition drive. Simulations are in better agreement with the off-Hugoniot performance of B4C than either HDC or GDP, and analytic estimations of the ablation pressure indicate that while the pressure produced by B4C and GDP is similar when the ablator is allowed to release, the pressure reached by B4C seems to exceed that of HDC when backed by a Au/quartz layer.

Experiments and analysis in the 3 years since the 2012 Target Fabrication Meeting have resulted in significant improvement in understanding of the requirements for high-performance layered implosio...

Study question What is the success rate in terms of ovarian activity (menstrual cycles) as well as pregnancy and delivery rates 1 year after orthotopic ovarian transplantations conducted in a three-country network? Summary answer In 49 women with a follow-up >1 year after transplantation, the ovaries were active in 67% of cases and the pregnancy and delivery rates were 33 and 25%, respectively. What is known already Cryopreservation of ovarian tissue in advance of cytotoxic therapies and later transplantation of the tissue is being performed increasingly often, and the total success rates in terms of pregnancy and delivery have been described in case series. However, published case series have not allowed either a more detailed analysis of patients with premature ovarian insufficiency (POI) or calculation of success rates based on the parameter 'tissue activity'. Study design, size, duration Retrospective analysis of 95 orthotopic transplantations in 74 patients who had been treated for cancer, performed in the FertiPROTEKT network from 2008 to June 2015. Of those 95 transplantations, a first subgroup (Subgroup 1) was defined for further analysis, including 49 women with a follow-up period >1 year after transplantation. Of those 49 women, a second subgroup (Subgroup 5) was further analysed, including 40 women who were transplanted for the first time and who were diagnosed with POI before transplantation. Participants/materials, setting, methods Transplantation was performed in 16 centres and data were transferred to the FertiPROTEKT registry. The transplantations were carried out after oncological treatment had been completed and after a remission period of at least 2 years. Tissue was transplanted orthotopically, either into or onto the residual ovaries or into a pelvic peritoneal pocket. The success rates were defined as tissue activity (menstrual cycles) after 1 year (primary outcome) and as pregnancies and deliveries achieved. Main results and the role of chance The average age of all transplanted 74 women was 31 ± 5.9 years at the time of cryopreservation and 35 ± 5.2 at the time of transplantation. Twenty-one pregnancies and 17 deliveries were recorded. In Subgroup 1, tissue was cryopreserved at the age of 30 ± 5.6 and transplanted at 34 ± 4.9 years. Ovaries remained active 1 year after transplantation in 67% of cases (n = 33/49), the pregnancy rate was 33% (n = 16/49) and the delivery rate was 25% (n = 12/49). In Subgroup 5, tissue was cryopreserved at the age 30 ± 5.9 years and transplanted at 34 ± 5.2 years. Ovaries remained active 1 year after transplantation in 63% of cases (n = 25/40), the pregnancy rate was 28% (n = 11/40) and the delivery rate was 23% (n = 9/40). The success rates were age dependant with higher success in women who cryopreserved at a younger age. In Subgroup 5, tissue was exclusively transplanted into the ovary in 10% (n = 4/40) of women and into a peritoneal pocket in 75% (n = 30/40), resulting in spontaneous conceptions in 91% of patients (n = 10/11). Limitations, reasons for caution The data were drawn from a retrospective analysis. The cryopreservation and transplantation techniques used have changed during the study period. The tissue was stored in many tissue banks and many surgeons were involved, leading to heterogeneity of the procedures. However, this does reflect the realistic situation in many countries. Although patients with POI were evaluated before transplantation to allow specific analysis of the transplanted tissue itself, the possibility cannot be excluded that residual ovarian tissue was also reactivated. Wider implications of the findings This is the largest case series worldwide to date and it confirms that cryopreservation and transplantation of ovarian tissue can be a successful option for preserving fertility. Persistent tissue activity 12 months after transplantation suggests that the pregnancy and delivery rates may increase further in the future. As transplantation into the peritoneum results in a high success rate, this approach may be an alternative to transplantation into the ovary. However, in order to establish the best transplantation site, a randomized study is required. Study funding/competing interest This study was in part funded from the Deutsche Forschungsgemeinschaft (# DI 1525) and the Wilhelm Sander Foundation (2012.127.1) and did not receive any funding from a commercial company. No competing interests. Trial registration number None.

Inertial confinement fusion, based on laser-heating a deuterium–tritium mixture, is one of the approaches towards energy production from fusion reactions. Now, record energy-yield experiments are reported—bringing us closer to ignition conditions.

Plasma jets, such as γ-ray burst jets, Herbig–Haro jets, μ-quasar jets, and active galactic nuclei jets, are found throughout the universe [S. Mendoza et al., Rev. Mex. Astron. Astrofis. 41, 453 (2005)]. Plasma jets are also present in indirect drive inertial confinement fusion experiments originating from the capsule's fill tube and occasionally from divots and voids in the capsules, particles on the exterior of the capsule, or from the tent holding the capsule in the target. This paper looks at two different gas-filled capsule implosions containing a plasma jet resulting from a capsule fill tube and fill channel, both of which utilized high density carbon ablators. Two models were developed, a drag and a snowplow model, which use the time-dependent motion of the injected mass through the hotspot to estimate the mass injected into the hotspot from the fill tube and channel, arriving at an average injected mass of ∼84.5 ± 25.5 ng for the first experiment and 91 ± 20 ng for the second experiment. Unlike previous methods to estimate fill tube injected mass, these techniques do not assume that the mixed mass is in thermal equilibrium with the hotspot or that the x-ray emission is only coming from within the hotspot itself. This paper also discusses the features seen in these experiments which include limb brightening in the shell for undoped ablators and flattening in the ablator from shadowing by the fill tube.

The micrometer-scale tube that fills capsules with thermonuclear fuel in inertial confinement fusion experiments at the National Ignition Facility is also one of the implosion's main degradation sources. It seeds a perturbation that injects the ablator material into the center, radiating away some of the hot-spot energy. This paper discusses how the perturbation arises in experiments using high-density carbon ablators and how the ablator mix interacts once it enters the hot-spot. Both modeling and experiments show an in-flight areal-density perturbation and localized x-ray emission at stagnation from the fill-tube. Simulations suggest that the fill-tube is degrading an otherwise 1D implosion by ∼2×, but when other degradation sources are present, the yield reduction is closer to 20%. Characteristics of the fill-tube assembly, such as the through-hole size and the glue mass, alter the dynamics and magnitude of the degradation. These aspects point the way toward improvements in the design, some of which (smaller diameter fill-tube) have already shown improvements.

Ignition is needed to make fusion energy a viable alternative energy source, but has yet to be achieved. A key step on the way to ignition is to have the energy generated through fusion reactions in an inertially confined fusion plasma exceed the amount of energy deposited into the deuterium-tritium fusion fuel and hotspot during the implosion process, resulting in a fuel gain greater than unity. Here we report the achievement of fusion fuel gains exceeding unity on the US National Ignition Facility using a 'high-foot' implosion method, which is a manipulation of the laser pulse shape in a way that reduces instability in the implosion. These experiments show an order-of-magnitude improvement in yield performance over past deuterium-tritium implosion experiments. We also see a significant contribution to the yield from α-particle self-heating and evidence for the 'bootstrapping' required to accelerate the deuterium-tritium fusion burn to eventually 'run away' and ignite.