Strigolactone analogues induce suicidal seed germination of Striga spp. in soil

Striga hermonthica and Striga asiatica are obligate root parasites that cause serious problems in the production of staple cereal crops in Africa. Because of the high levels of infestation, there is an urgent need to control these weeds. A potentially useful control option is depletion of the soil seed bank by suicidal germination, which involves germination of the seeds in the absence of host plants. Suicidal germination is often mentioned in the literature, but not considered realistic, because of the alleged untimely decomposition of the stimulants in the soil, despite the fact that some encouraging results were reported around 1980. The alleged instability has prevented active research in this direction for the past 20–25 years. Five newly designed synthetic germination stimulants were investigated as candidates for suicidal germination. An important issue is the persistence of these stimulants in soil. Packets with Striga spp. seeds were put in pots with soil and then treated with aqueous solutions of the stimulants. All five compounds induced germination under these conditions, with percentages varying between 18% and 98% depending on stimulant and species. There were no noticeable signs of decomposition of the stimulants. The best performing stimulant is derived from 1-tetralone. We conclude that synthetic strigolactones analogues have excellent prospects for use in combating parasitic weeds. Further testing will be needed to evaluate whether such prospects can be realised in the field

The anatomy and function of Cleland's ligaments

The cutaneous ligaments of the digits have been recognized by anatomists for several centuries, but the best known description is that of John Cleland. Subsequent varying descriptions of their morphology have resulted in the surgical community having an imprecise view of their structure and dynamic function. We micro-dissected 24 fresh frozen fingers to analyze the individual components of Cleland's ligamentous system. Arising from the proximal interphalangeal (PIP) joint, proximal, and sometimes middle phalanx, we found strong ligaments that ran proximally (PIP-P) and distally (PIP-D). On each side of each finger there was a PIP-P ligament present, which passed obliquely from the lateral side of the proximal and sometimes middle phalanx towards its insertion into the skin at the level of the proximal phalanx. The distal (PIP-D) ligaments were found to pass obliquely distally on the radial and ulnar aspects of the digit towards cutaneous insertions around the middle phalanx. A similar arrangement exists more distally with fibres originating from the DIP joint and middle phalanx (the DIP-P pass obliquely proximally, and the DIP-D, distally). Each individual PIP ligament consisted of three different layers originating from fibres overlying the flexor tendon sheath, periosteum or joint capsule, and extensor expansion. Ligaments arising at the DIP joint had two layers equivalent to the anterior two layers of the proximal ligaments. Cleland's ligaments act as skin anchors maintaining the skin in a fixed relationship to the underlying skeleton during motion and functional tasks. They also prevent the skin from 'bagging', protect the neurovascular bundle, and create a gliding path for the lateral slips of the extensor tendon

Relationship between bullet diameter and bullet defect diameter in human calvariums

Existing literature on the relationship between bullet diameter and bullet defect diameter in the human calvarium is summarized and discussed. The hypothesis, derived from the literature, that bullet deformation influences bullet defect diameter was studied in a small controlled experiment. The mean defect size caused by non-deforming projectiles was found to be smaller than the mean defect size caused by deforming projectiles of equal original mass and size. The p value of the difference between the two means, measured in two different ways, was found to be 0.002 for both in a Mann-Whitney U test and was significant if the confidence level is set at 5%

Quantitative live-cell imaging and computational modelling shed new light on endogenous WNT/CTNNB1 signaling dynamics

WNT/CTNNB1 signaling regulates tissue development and homeostasis in all multicellular animals, but the underlying molecular mechanism remains incompletely understood. Specifically, quantitative insight into endogenous protein behavior is missing. Here, we combine CRISPR/Cas9-mediated genome editing and quantitative live-cell microscopy to measure the dynamics, diffusion characteristics and absolute concentrations of fluorescently tagged, endogenous CTNNB1 in human cells under both physiological and oncogenic conditions. State-of-the-art imaging reveals that a substantial fraction of CTNNB1 resides in slow-diffusing cytoplasmic complexes, irrespective of the activation status of the pathway. This cytoplasmic CTNNB1 complex undergoes a major reduction in size when WNT/CTNNB1 is (hyper)activated. Based on our biophysical measurements, we build a computational model of WNT/CTNNB1 signaling. Our integrated experimental and computational approach reveals that WNT pathway activation regulates the dynamic distribution of free and complexed CTNNB1 across different subcellular compartments through three regulatory nodes: the destruction complex, nucleocytoplasmic shuttling, and nuclear retention

Thinner Regions of Intracranial Aneurysm Wall Correlate with Regions of Higher Wall Shear Stress: A 7T MRI Study

BACKGROUND AND PURPOSE: Both hemodynamics and aneurysm wall thickness are important parameters in aneurysm pathophysiology. Our aim was to develop a method for semi-quantitative wall thickness assessment on in vivo 7T MR images of intracranial aneurysms for studying the relation between apparent aneurysm wall thickness and wall shear stress. MATERIALS AND METHODS: Wall thickness was analyzed in 11 unruptured aneurysms in 9 patients who underwent 7T MR imaging with a TSE-based vessel wall sequence (0.8-mm isotropic resolution). A custom analysis program determined the in vivo aneurysm wall intensities, which were normalized to the signal of nearby brain tissue and were used as measures of apparent wall thickness. Spatial wall thickness variation was determined as the interquartile range in apparent wall thickness (the middle 50% of the apparent wall thickness range). Wall shear stress was determined by using phase-contrast MR imaging (0.5-mm isotropic resolution). We performed visual and statistical comparisons (Pearson correlation) to study the relation between wall thickness and wall shear stress. RESULTS: 3D colored apparent wall thickness maps of the aneurysms showed spatial apparent wall thickness variation, which ranged from 0.07 to 0.53, with a mean variation of 0.22 (a variation of 1.0 roughly means a wall thickness variation of 1 voxel [0.8 mm]). In all aneurysms, apparent wall thickness was inversely related to wall shear stress (mean correlation coefficient, −0.35; P < .05). CONCLUSIONS: A method was developed to measure the wall thickness semi-quantitatively, by using 7T MR imaging. An inverse correlation between wall shear stress and apparent wall thickness was determined. In future studies, this noninvasive method can be used to assess spatial wall thickness variation in relation to pathophysiologic processes such as aneurysm growth and rupture

Clinical applications of 7T MRI in the brain

AbstractThis review illustrates current applications and possible future directions of 7Tesla (7T) Magnetic Resonance Imaging (MRI) in the field of brain MRI, in clinical studies as well as clinical practice. With its higher signal-to-noise (SNR) and contrast-to-noise ratio (CNR) compared to lower field strengths, high resolution, contrast-rich images can be obtained of diverse pathologies, like multiple sclerosis (MS), brain tumours, aging-related changes and cerebrovascular diseases. In some of these diseases, additional pathophysiological information can be gained compared to lower field strengths. Because of clear depiction of small anatomical details, and higher lesion conspicuousness, earlier diagnosis and start of treatment of brain diseases may become possible. Furthermore, additional insight into the pathogenesis of brain diseases obtained with 7T MRI could be the basis for new treatment developments. However, imaging at high field comes with several limitations, like inhomogeneous transmit fields, a higher specific absorption rate (SAR) and, currently, extensive contraindications for patient scanning. Future studies will be aimed at assessing the advantages and disadvantages of 7T MRI over lower field strengths in light of clinical applications, specifically the additional diagnostic and prognostic value of 7T MRI

El Plan Estratégico y el Desarrollo Económico Local de la Ciudad de Córdoba, Argentinade

The Strategic Plan of Córdoba (PEC) is one of the few strategic urban development plans in Latin America which has actually been implemented in the majority of its components. The PEC was conceived as a collective and global project of the city as a whole without excessive protagonism or special ownership by a few. The PEC integrated a policy of public works – oriented at the “social debt” which existed in the city – with a work on urbanistic norms and directions and economic development. The PEC as a space for articulation achieved to organise a great number of representatives from civil society organisations, achieving legitimacy and representation in the work of the PEC