Genetics of barley tiller and leaf development

In cereals, tillering and leaf development are key factors in the concept of crop ideotype, introduced in the 1960 s to enhance crop yield, via manipulation of plant architecture. In the present review, we discuss advances in genetic analysis of barley shoot architecture,focusing on tillering, leaf size and angle. We also discuss novel phenotyping techniques, such as 2 D and 3 D imaging, that have been introduced in the era of phenomics, facilitating reliable trait measurement. We discuss the identification of genes and pathways that are involved in barley tillering and leaf development,highlighting key hormones involved in the control of plant architecture in barley and rice. Knowledge on genetic control of traits related to plant architecture provides useful resources for designing ideotypes for enhanced barley yield and performance.     

Out-of-Africa,human-mediated dispersal of the common cat flea,Ctenocephalides felis: The hitchhiker’s guide to world domination

The cat flea (Ctenocephalides felis) is the most common parasite of domestic cats and dogs worldwide. Due to the morphological ambiguity of C. felis and a lack of — particularly largescale — phylogenetic data, we do not know whether global C. felis populations are morphologically and genetically conserved, or whether human-mediated migration of domestic cats and dogs has resulted in homogenous global populations. To determine the ancestral origin of the species and to understand the level of global pervasion of the cat flea and related taxa, our study aimed to document the distribution and phylogenetic relationships of Ctenocephalides fleas found on cats and dogs worldwide. We investigated the potential drivers behind the establishment of regional cat flea populations using a global collection of fleas from cats and dogs across six continents. We morphologically and molecularly evaluated six out of the 14 known taxa comprising genus Ctenocephalides, including the four original C. felis subspecies (Ctenocephalides felis felis, Ctenocephalides felis strongylus, Ctenocephalides felis orientis and Ctenocephalides felis damarensis), the cosmopolitan species Ctenocephalides canis and the African species Ctenocephalides connatus. We confirm the ubiquity of the cat flea, representing 85% of all fleas collected (4357/5123). Using a multigene approach combining two mitochondrial (cox1 and cox2) and two nuclear (Histone H3 and EF-1α) gene markers, as well as a cox1 survey of 516 fleas across 56 countries, we demonstrate out-of-Africa origins for the genus Ctenocephalides and high levels of genetic diversity within C. felis. We define four bioclimatically limited C. felis clusters (Temperate, Tropical I, Tropical II and African) using maximum entropy modelling. This study defines the global distribution, African origin and phylogenetic relationships of global Ctenocephalides fleas, whilst resolving the taxonomy of the C. felis subspecies and related taxa. We show that humans have inadvertently precipitated the expansion of C. felis throughout the world, promoting diverse population structure and bioclimatic plasticity. By demonstrating the link between the global cat flea communities and their affinity for specific bioclimatic niches, we reveal the drivers behind the establishment and success of the cat flea as a global parasite.     

Stereotactic radiotherapy for brain oligometastases

Brain metastases, the most common metastases in adults, will develop in up to 40% of cancer patients, accounting for more than one-half of all intracranial tumors. They are most associated with breast and lung cancer, melanoma and, less frequently, colorectal and kidney carcinoma.Magnetic resonance imaging (MRI) is the gold standard for diagnosis. For the treatment plan, computed tomography (CT ) images are co-registered and fused with a gadolinium-enhanced T1-weighted MRI where tumor volume and organs at risk are contoured. Alternatively, plain and contrast-enhanced CT scans are co-registered. Single-fraction stereotactic radiotherapy (SRT ) is used to treat patients with good performance status and up to 4 lesions with a diameter of 30 mm or less that are distant from crucial brain function areas. Fractionated SRT (2–5 fractions) is used for larger lesions, in eloquent areas or in proximity to crucial or surgically inaccessible areas and to reduce treatment-related neurotoxicity. The single-fraction SRT dose, which depends on tumor diameter, impacts local control. Fractionated SRT may encompass different schedules. No randomized trial data compared the safety and efficacy of single and multiple fractions. Both single-fraction and fractionated SRT provide satisfactory local control rates, tolerance, a low risk of transient acute adverse events and of radiation necrosis the incidence of which correlated with the irradiated brain volume.     

Biomimetic soluble collagen purified from bones

Type I collagen has been extensively exploited as a biomaterial for biomedical applications and drug delivery; however, small molecular alterations occurring during the isolation procedure and its interaction with residual bone extracellular matrix molecules or proteins might affect the overall material biocompatibility and performance. The aim of the current work is to study the potential alterations in collagen properties and organization associated with the absence of proteoglycans, which mimic pathological conditions associated with age‐related diseases. A new approach for evaluating the effect of proteoglycans on the properties of isolated type I collagen from the bone matrix is described. Additional treatment with guanidine hydrochloride was introduced to remove residual proteoglycans from the collagen matrix. The properties of the isolated collagen with/without guanidine hydrochloride treatment were investigated and compared with a commercial rabbit collagen as control. We demonstrate that the absence of proteoglycans in the isolated type I collagen affects its thermal properties, the extraction into its native structure, and its ability to hydrate and self‐assemble into fibers. The fine control and tuning of all these features, linked to the absence of non‐collagenous proteins as proteoglycans, offer the possibility of designing new strategies and biomaterials with advanced biomimetic properties aimed at regenerating bone tissue in the case of fragility and/or defects.     

Diterpenoid resin acids of Daemonorops draco

Chromatography of a cyclohexane extract of commercial “dragon's blood” resin yielded a fraction containing pimaric, isopimaric, dehydroabietic and abietic acids. A fifth component of the mixture was tentatively identified as sandaracopimaric acid.     

Chemical Composition,Enantiomeric Analysis,AEDA Sensorial Evaluation and Antifungal Activity of the Essential Oil from the Ecuadorian Plant Lepechinia mutica Benth (Lamiaceae)

This study describes the GC‐FID, GC/MS, GC‐O, and enantioselective GC analysis of the essential oil hydrodistilled from leaves of Lepechinica mutica (Lamiaceae), collected in Ecuador. GC‐FID and GC/MS analyses allowed the characterization and quantification of 79 components, representing 97.3% of the total sample. Sesquiterpene hydrocarbons (38.50%) and monoterpene hydrocarbons (30.59%) were found to be the most abundant volatiles, while oxygenated sesquiterpenes (16.20%) and oxygenated monoterpenes (2.10%) were the minor components. In order to better characterize the oil aroma, the most important odorants, from the sensorial point of view, were identified by Aroma Extract Dilution Analysis (AEDA) GC‐O. They were α‐Pinene, β‐Phellandrene, and Dauca‐5,8‐diene, exhibiting the characteristic woody, herbaceus, and earthy odors, respectively. Enantioselective GC analysis of L. mutica essential oil revealed the presence of twelve couples and two enantiomerically pure chiral monoterpenoids. Their enantiomeric excesses were from a few percent units to 100%. Moreover, the essential oil exhibited moderate in vitro activity against five fungal strains, being especially effective against M. canis, which is a severe zoophilic dermatophyte causal agent of pet and human infections.     

Conceptual design and implantation of an external fixator with improved mobility for knee rehabilitation

A hinged external fixator is used to allow early knee rehabilitation in case of injury or trauma, as an alternative approach to immobilization. It is mainly adopted for the treatment of dislocations, which involve tearing of the ligaments, and it basically consists of two links connected to each other by a revolute joint. Each link is fixed to the femur and tibia via pin fixation, and the revolute joint is approximately aligned to the knee flexion-extension (FE) axis. The advantage in its implantation is to protect ligament reconstruction, while allowing for an aggressive rehabilitation. Traditional fixators only accommodate the functional flexion movement in a limited range, i.e. where the anatomical movement is closer to a planar circular trajectory. This paper presents the conceptual design and implantation procedure of a double-axis fixator, which accommodates both FE and longitudinal internal-external rotation. The procedure is based on accurate knee kinematics measurements and on computer-aided multibody simulations to assist clinicians in the implantation. An experimental test is presented using an artificial knee, and guidelines are given for in vitro studies. The proposed technique may allow for a better understanding of knee kinematics and have the potential advantage to increase the range of motion in postoperative rehabilitation.