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Compact and broadband mid-infrared (MIR) sources are in high demand because of a wide range of potential applications such as molecular sensing in the fingerprint region. The generation of coherent MIR radiation at arbitrary frequencies typically requires nonlinear mixing between at least two input waves, which is often cumbersome to implement. We present an integrated and, therefore, adjustment-free solution combining few-femtosecond pulse compression in a germanosilicate optical fiber and optical rectification. To this end, a 16-μm-thin GaSe crystal is directly mounted on the end facet of a highly nonlinear fiber assembly exploiting a focused ion beam. With input pulses of a minute energy of 5 nJ and a duration of 120 fs at the telecom wavelength of 1.55 μm, we directly obtain ultrabroadband and phase-stable output transients. Electro-optic sampling in free space reveals single-cycle pulses with spectral components covering the entire MIR from 10 to 120 THz. [ABSTRACT FROM AUTHOR]

With an increased number of pet reptiles, many diseases occur due to nutritional disorders. Between 2013 and 2015, irregular gallbladder contents (sludge/choleliths) in adult bearded dragons ( Pogona vitticeps) were recorded in many of the routinely conducted necropsies at the reptile rescue station in Munich (Auffangstation für Reptilien, München e.V., Munich, Germany). Nine animals, six from the rescue station and three from an associated veterinary practice (Tierärztliche Praxis für Exoten, Augsburg, Germany), were studied. Gallbladder contents from all animals were analysed at the Institute for Clinical Chemistry in Zurich, Switzerland. In three of nine animals, one cholelith composed of 100% calcium carbonate (CaCO3) was detected and it precipitated either as pure calcite or as a calcite:vaterite combination. In the remaining six animals, analyses suggested a protein-based material. The detection of choleliths/sludge was not anticipated at necropsy or surgery in eight of nine animals. The diet of the six animals from the rescue station was retrospectively described as mainly insects, whereas the diet of the three animals from the veterinary practice also contained little plant matter. Fed insect species were mealworm larva ( Tenebrio molitor), house cricket ( Acheta domestica), migratory locust ( Locusta migratoria) and zophobas larva ( Zophobas morio), all high in protein and fat. In other species, a nidus must be present for Ca CO3 to precipitate. As a protein-based sludge was detected in six gallbladders, it is possible that a high-protein diet could lead to such a nidus and subsequently to cholelith formation. Cholelithiasis seems to be a rising problem in adult bearded dragons and is likely underdiagnosed, as many choleliths were found at necropsy. This rise in cholelithiasis may correlate with an unnatural high-protein, high-fat insect-based diet instead of a balanced plant-based diet. [ABSTRACT FROM AUTHOR]

Multicellular tumour spheroids are realistic in vitro systems in radiation research that integrate cell-cell interaction and cell cycle control by factors in the medium. The dynamic reaction inside a tumour spheroid triggered by radiation is not well understood. Of special interest is the amount of cell cycle synchronisation which could be triggered by irradiation, since this would allow follow-up irradiations to exploit the increased sensitivity of certain cell cycle phases. In order to investigate these questions we need to support irradiation experiments with mathematical models. In this article a new model is introduced combining the dynamics of tumour growth and irradiation treatments. The tumour spheroid growth is modelled using an agent-based Delaunay/Voronoi hybrid model in which the cells are represented by weighted dynamic vertices. Cell properties like full cell cycle dynamics are included. In order to be able to distinguish between different cell reactions in response to irradiation quality we introduce a probabilistic model for damage dynamics. The overall cell survival from this model is in agreement with predictions from the linear-quadratic model. Our model can describe the growth of avascular tumour spheroids in agreement to experimental results. Using the probabilistic model for irradiation damage dynamics the classic 'four Rs' of radiotherapy can be studied in silico. We found a pronounced reactivation of the tumour spheroid in response to irradiation. A majority of the surviving cells is synchronized in their cell cycle progression after irradiation. The cell synchronisation could be actively triggered and should be exploited in an advanced fractionation scheme. Thus it has been demonstrated that our model could be used to understand the dynamics of tumour growth after irradiation and to propose optimized fractionation schemes in cooperation with experimental investigations. [ABSTRACT FROM AUTHOR]

The effect of a culture filtrate of Erwinia herbicola B 247 and the antibiotic herbicolin A, respectively, on the hyphae of Fusarium culmorum was studied in vitro using light and electron microscopy. The light microscopy revealed a swelling and disruption of the hyphae tips with a release of cytoplasm. Ultrastructural investigations demonstrated the appearance of electron-dense material of a round or tubular structure in the cell wall On its inner side, an accumulation of electron-dense material formed a spongy structure associated with the altered plasma membrane. Finally, a complete dissolution of the cell wall was observed. [ABSTRACT FROM AUTHOR]

Stunting is a major health problem in low-income countries. We aimed to describe the implementation of a lipid-based nutrient supplement (LNS) program in a rural neighborhood in Cambodia and to assess its impact on statural growth. This was a before–after comparative study. The program was promoted by the Pédiatres du Monde (PDM) organization between 2011 and 2019 in six villages in a rural area in Cambodia. The supplementation program consisted of daily administration of LNS during the third semester of pregnancy for the mothers and then between 6 and 24 months of age for the toddlers. Anthropometric data of the children were recorded during PDM visits before and after the program implementation, which allowed us to compare child growth in the two groups: control and intervention groups. Primary outcome was height-for-age between 24 and 35 months of age. Overall, 198 data were collected for children between 24 and 35 months of age in the control group. A total of 347 pregnant women were enrolled in the intervention phase. A total of 188 data were collected for children between 24 and 35 months of age in the intervention group. The mean height-for-age z-score in the population receiving LNS was higher than in the control group (−1.14 vs. −1.60, p < 0.001). There was no significant difference between the two groups regarding the weight-for-height z-score (WHZ; −1.11 vs. −1.26, p = 0.18) and children in the intervention group had a higher middle upper-arm circumference z-score (MUACZ; −0.75 vs.. −1.1, p < 0.001). LNS supplementation significantly and increased the HAZ between 24 and 35 months of age. However, the fight against malnutrition is complex and needs intervention on multiple levels. [ABSTRACT FROM AUTHOR]

An abstract of the article "Hypoxia/Reoxygenation Induces Neonatal Cardiomyocyte Hypertrophy: Activation of CREB Downstream of PI3K and ERK Pathway," by A. El Jamali and colleagues is presented.

The article discusses a study which demonstrated profound in vivo enrichment of genetically modified hematopoietic cells and clinical benefits as compared to a disease matched control group thereby establishing a proof-of-concept for the clinical applicability and efficacy of myeloprotective gene therapy approaches. It suggests that dCK knockdown may be a potentially promising strategy to prevent severe myelotoxicity in the context of chemotherapy with fludarabine. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) is one of the major fungal diseases in wheat throughout the world. To control FHB severity, breeding genetically resistant varieties is thought to be the most promising strategy. In wheat breeding programmes, short cultivars predominantly carrying the Norin 10 derived semi-dwarfing allele Rht-D1b ( Rht2) are preferred worldwide because of higher achievable grain yields and lower risk of lodging. This study was conducted to determine the influence of different alleles at the Rht-D1 locus on FHB reaction. Three winter wheat populations were produced by crossing rather susceptible varieties ‘Biscay’, ‘Pirat’ and ‘Rubens’ carrying mutant-type allele Rht-D1b with the more resistant varieties ‘Apache’, ‘Romanus’ and ‘History’ containing the Rht-D1a wild-type allele ( rht2). The 190, 216 and 103 progeny of the F4-derived populations were assayed for the presence of Rht-D1a or Rht-D1b, plant height, and mean FHB rating after spray inoculation at flowering time with a highly aggressive isolate of Fusarium culmorum. Comparably, high mean FHB severities ranging from 28% to 49% for all population × environment combinations were achieved, with significant genotypic variation for FHB rating and plant height within all populations. Both traits were negatively correlated with r ranging from −0.48 to −0.61 in the complete populations. However, within the subpopulations homozygous for one or other height allele these correlations decreased considerably. The Rht-D1b semi-dwarfing allele resulted in 7–18% shorter plants, depending on the population, but a considerably increased FHB reaction of 22–53%. Nevertheless, significant genotypic variance for FHB resistance remained in all tested Rht-D1b subpopulations indicating that selection for moderately FHB resistant genotypes within agronomically beneficial Rht-D1b genotypes is still feasible. [ABSTRACT FROM AUTHOR]

Bien que l'association entre le syndrome métabolique (SMet) et l'arthrose soit désormais classiquement acceptée, une meilleure compréhension des rôles respectifs et combinatoires de ses différents composants dans l'initiation et/ou la progression de l'arthrose est nécessaire pour établir de nouveaux concepts thérapeutiques. Dans ce contexte, nous avons étudié le phénotype articulaire de rats SHHF qui développent un SMet bien caractérisé. Nos travaux ont ainsi mis en évidence une arthrose sévère chez ces rats porteurs d'un SMet. Ils révèlent par ailleurs que le récepteur aux minéralocorticoïdes (RM) est un acteur essentiel dans le développement d'une arthrose métabolique puisqu'un traitement chronique par l'éplérénone, un antagoniste du RM, est capable de prévenir l'apparition des lésions articulaires dans ce modèle d'arthrose [1]. Basés sur ces résultats, nous avons cherché à établir la contribution du RM aux modifications phénotypiques des chondrocytes induites par 2 composants du SMet: la dyslipidémie et l'hyperglycémie. Des chondrocytes primaires isolés à partir de têtes fémorales de rats Wistar ou de cartilage humain obtenu après une arthroplastie totale de genou ont été stimulés par un acide gras saturé l'acide palmitique (AP, 0,1 à 0,5 mM) en présence de concentration normale (1 g/L) ou élevée (4,5 g/L) de glucose. Une stimulation à l'IL1ß a également été réalisée à titre de comparaison. La réponse chondrocytaire a été évaluée par l'étude de l'expression de marqueurs inflammatoires (COX2, mPGES, iNOS, IL1) et du remodelage de la matrice extracellulaire (TGFß, MMPs). Nos travaux montrent que l'AP induit de manière dose-dépendante l'expression de marqueurs inflammatoires et dégénératifs. La présence simultanée d'un taux élevé de glucose accroît les effets délétères de l'AP. Après avoir mis en évidence l'expression du RM dans les chondrocytes de rats, le traitement des chondrocytes avec l'éplérénone (3,10 et 30 μM) démontre les propriétés inhibitrices de cet antagoniste du RM sur l'effet inflammatoire de l'AP dès la concentration de 3 μM. Cette activité est déjà observée après seulement 6 heures de traitement et se maintient jusqu'à 24 h. Elle est cependant moins efficace pour s'opposer à l'effet pro-inflammatoire de l'IL1ß puisqu'une concentration de 30 μM est nécessaire pour réduire très transitoirement l'expression de COX-2 induite par l'IL1ß. La réponse des chondrocytes humains à l'AP et au glucose est identique à celle observée chez le rat, mais reste inchangée après un traitement à l'éplérénone. Grâce au financement par la SFR, nous avons démontré la présence du RM dans les chondrocytes de rats, suggérant ainsi un rôle local du RM dans le développement des lésions articulaires. Les effets bénéfiques de l'éplérénone sur la réponse inflammatoire et dégénérative induite par 2 composants du SMet confirment, d'une part, les données observées in vivo chez les rats porteurs d'un SMet et indiquent, d'autre part, que le RM pourrait également contribuer au développement de l'arthrose par des effets no seulement systémiques, mais également locaux. L'absence d'effet de l'éplérénone sur des chondrocytes stimulés à l'IL1ß suggère que le RM serait impliqué dans les formes d'arthrose uniquement associées au SMet. Chez l'homme, les effets de l'éplérénone ne sont pas retrouvés, indiquant qu'il existe une différence d'activité selon le phénotype des chondrocytes (sains vs arthrosiques) et/ou selon l'espèce (rat vs humain) liée ou non à une différence d'affinité de l'éplérénone pour le RM. [ABSTRACT FROM AUTHOR]