Multiangle static and dynamic light scattering in the intermediate scattering angle range

We describe a light scattering apparatus based on a novel optical scheme covering the scattering angle range 0.5\dg \le \theta \le 25\dg, an intermediate regime at the frontier between wide angle and small angle setups that is difficult to access by existing instruments. Our apparatus uses standard, readily available optomechanical components. Thanks to the use of a charge-coupled device detector, both static and dynamic light scattering can be performed simultaneously at several scattering angles. We demonstrate the capabilities of our apparatus by measuring the scattering profile of a variety of samples and the Brownian dynamics of a dilute colloidal suspension

Granular cell tumor of the toe: a case report

Granular cell tumor is a rare tumor of unknown etiology that more commonly affects the oral cavity but can also occur at other sites. The majorities of granular cell tumors are benign and present as a singular dermal nodule. We discuss a case of granular cell tumor of the fourth toe in a 54-year-old patient that was treated with conservative surgery, instead of amputation, and reconstruction with a dermal regeneration template

An overview of coumarin as a versatile and readily accessible scaffold with broad-ranging biological activities

Privileged structures have been widely used as an effective template for the research and discovery of high value chemicals. Coumarin is a simple scaffold widespread in Nature and it can be found in a considerable number of plants as well as in some fungi and bacteria. In the last years, these natural compounds have been gaining an increasing attention from the scientific community for their wide range of biological activities, mainly due to their ability to interact with diverse enzymes and receptors in living organisms. In addition, coumarin nucleus has proved to be easily synthetized and decorated, giving the possibility of designing new coumarin-based compounds and investigating their potential in the treatment of various diseases. The versatility of coumarin scaffold finds applications not only in medicinal chemistry but also in the agrochemical field as well as in the cosmetic and fragrances industry. This review is intended to be a critical overview on coumarins, comprehensive of natural sources, metabolites, biological evaluations and synthetic approaches

Rationalizing the Lacking of Inversion Symmetry in a Noncentrosymmetric Polar Racemate : an Experimental and Theoretical Study

The total charge density of PYRAC, a polar (Pca21) organic racemate with Z\u2032 = 2, was derived from high-resolution single-crystal X-ray diffraction data at T = 100(2) K and periodic DFT calculations. The PYRAC asymmetric unit consists of a hydrogen-bonded pair of conformationally different enantiomers, A and Bi, where the subscript \u201ci\u201d indicates a reversed absolute configuration. The lattice stability was compared with that of centrosymmetric possibly competing structures, with the aim of understanding why a noncentrosymmetric lattice framework is obtained from a racemic mixture. The likelihood of specific intermolecular recognition processes among different conformers of PYRAC in the very first stages of nucleation was investigated by DFT simulations in vacuo. Two competing, equivalent interconversion pseudorotatory paths between the most stable A and the least stable B conformers were found. It results that molecules spend most of their time ( 4853%) in the A conformation, whereas the B one is far less populated ( 487%). Therefore, centrosymmetric AAi adducts are formed very frequently in the reaction liquor, whereas the BBi ones are rare. Nevertheless, AAi pairs produce crystal forms with cohesive energies and densities significantly less favorable than those estimated for the noncentrosymmetric heterochiral ABi ones. Therefore, preference for Z\u2032 = 2 in conjunction with noncentrosymmetric point and space groups results from the thermodynamic control of the crystallization process. The capability of forming extended hydrogen bond chains throughout the lattice appears to be a prerequisite to bind together the fundamental ABi repeating units

Folates in Trypanosoma brucei: achievements and opportunities

Trypanosoma brucei is the agent of human African trypanosomiasis (HAT), a neglected disease that threatens the lives of 65 million people in sub-Saharan Africa every year. Unfortunately, available therapies are unsatisfactory, due primarily to safety issues and development of drug resistance. Over the last decades significant effort has been made in the discovery of new potential anti-HAT agents, with help from the World Health Organization (WHO) and private\u2013public partnerships such as the Drugs for Neglected Diseases Initiative (DNDi). Whereas antifolates have been a valuable source of drugs against bacterial infections and malaria, compounds effective against T. brucei have not yet been identified. Considering the relatively simple folate metabolic pathway in T. brucei, along with results obtained in this research field so far, we believe that further investigations might lead to effective chemotherapeutic agents. Herein we present a selection of the more promising results obtained so far in this field, underlining the opportunities that could lead to successful therapeutic approaches in the future

Chronic exertional compartment syndrome of the forearm: a systematic review

The aim of this systematic review is to understand which surgical procedure provides better results in terms of pain relief and function in the treatment of chronic exertional compartment syndrome (CECS) of the forearm. We searched Medline (PubMed), Web of Science, Embase and Scopus databases on 8 July 2020. Twelve studies were included in this review. We assessed the quality of the studies using the Coleman Methodological Score. Data on demographic features, operative readings, diagnostic methods, follow-up periods, type and rates of complications, survivorship of the procedure, return to sport activity, and outcome measures were recorded. In conclusion, compared to the other techniques, endoscopic fasciotomy delivers similar success rates and lower incidence of complications

Sweet-and-salty biocatalysis : fructooligosaccharides production using Cladosporium cladosporioides in seawater

Production of fructooligosaccharides (FOS) from sucrose was obtained using a bioprocess entirely performed in seawater. The halophilic fungus Cladosporium cladosporioides MUT 5506 was grown in a seawater-based medium and mycelium displayed an optimal activity in seawater at 50\u201360 \ub0C, being stable up to 60 \ub0C. Under optimized conditions in seawater (50 \ub0C, sucrose 600 g/L, lyophilized mycelium 40 g/L), C. cladosporioides gave a maximum FOS yield of 344 g/L after 72 h with a preponderance of 1F-FOS derivatives (1-kestose 184 g/L, 1-nystose 98 g/L and 1-fructofuranosylnystose 22 g/L), and the noteworthy presence of the non-conventional disaccharide blastose (30 g/L after 144 h). Lyophilized mycelium exhibited good stability in seawater (76% of the initial activity was retained after 15 cycles of reutilization). This proof-of-concept application reports for the first time the production of FOS in a non-conventional medium such as seawater

Compact, multi-exposure speckle contrast optical spectroscopy (SCOS) device for measuring deep tissue blood flow

Speckle contrast optical spectroscopy (SCOS) measures absolute blood flow in deep tissue, by taking advantage of multi-distance (previously reported in the literature) or multiexposure (reported here) approach. This method promises to use inexpensive detectors to obtain good signal-to-noise ratio, but it has not yet been implemented in a suitable manner for a mass production. Here we present a new, compact, low power consumption, 32 by 2 single photon avalanche diode (SPAD) array that has no readout noise, low dead time and has high sensitivity in low light conditions, such as in vivo measurements. To demonstrate the capability to measure blood flow in deep tissue, healthy volunteers were measured, showing no significant differences from the diffuse correlation spectroscopy. In the future, this array can be miniaturized to a low-cost, robust, battery operated wireless device paving the way for measuring blood flow in a wide-range of applications from sport injury recovery and training to, on-field concussion detection to wearables