SciCombinator

Discover the most talked about and latest scientific content & concepts.

 

0

As the reproductive technology advanced along with the improved outcome in cancer treatment demands implementing new fertility preservation. Developing algorithms on fertility preservation requires tailoring for each society. Here authors attempts to modify the current medical literature on fertility preservation for Turkish population.

0

The climacteric syndrome related to many symptoms often causes discomfort in women. Nonpharmacological treatment is one of the treatment options for these individuals, and this syndrome can be cured with psychological treatments such as CBT. The present study aimed to compare the efficacy of various CBT methods on the improvement of climacteric symptoms.

0

Chronic liver disease is a major disorder worldwide. A better understanding of anatomy, blood flow, and pathophysiology may be a key issue for their proper management. Ultrasound (US) is a simple and non-invasive diagnostic tool in the abdominal field. Doppler mode offers real-time hemodynamic evaluation, and the contrast-enhanced US is one of the most frequently used modalities for the detailed assessment. Further development in digital technology enables threedimensional (3D) visualization of target images with high resolution. This article reviews the wide ranges of application in the abdominal US and describes the recent progress in the diagnosis of chronic liver diseases.

0

Nanopore-based resistive pulse sensing with biological nanopores has traditionally been applied to biopolymer analysis, but more recently, interest has grown in applying the technique to characterizing water-soluble metallic clusters. This paper reports on the use of alpha hemolysin (αHL) for detecting a variety of thiolate-capped gold nanoclusters. The ligands studied here are p-mercaptobenzoic acid (p-MBA), tiopronin (TP) and thiolated PEG7 (S-PEG7). Individual clusters trapped in the cis-side of an αHL pore for extended periods (>10 sec) exhibit fluctuations between numerous substates. We compare these current steps between the three different ligands and find that they scale with the mass of the corresponding ligand, which suggests that nanopore sensing could be used to characterize intraparticle surface modifications.

0

Conventional DNA quantification methods require a DNA purification step that limits their reliability in estimating the original DNA amount, especially in complex matrix. To overcome this limitation, we developed a method to calibrate the variable DNA extraction efficiencies during the purification process, allowing for the accurate quantification of DNA in complex matrix. This method is based on isotope dilution-liquid chromatography mass spectrometry using stable isotope-labeled DNA (SILD) as an internal standard. Steps include spiking prepared SILD into samples, purification, enzymatic hydrolysis, and detection of DNA monomers via mass spectrometry, where the spiked SILD is expected to behave the same as the target DNA throughout the entire procedure. We show that the mean recoveries of four different DNA purification kits were dramatically improved by using the SILD internal standard, both for E. coli and human genomic DNA. As standards for calibration, deoxyribonucleoside monophosphates and purified genomic DNA were tested, with genomic DNA from corresponding species found to calibrate the variable extraction efficiencies more effectively. With this successful calibration, our newly developed procedure enables SI-traceable quantification of total DNA in complex matrix.

0

The increasing prevalence of fentanyl and its analogues as a contaminating material in illicit drug products presents a major hazard to first responder and law enforcement communities. Electrochemical techniques have the potential to provide critical information to these personnel via rapid, facile field detection of these materials. Here we demonstrate the use of cyclic square wave voltammetry (CSWV) with screen-printed carbon electrodes (SPCE), modified with the Room Temperature Ionic Liquid (RTIL) 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide [C4C1pyrr][NTf2], towards such rapid ‘on-the-spot’ fentanyl detection. This CSWV-based disposable sensor strip system provides an information-rich electrochemical fingerprint of fentanyl, composed of an initial oxidation event at +0.556 V (vs. Ag/AgCl) and a reversible reduction and oxidation reaction at -0.235 and -0.227 V, respectively. The combined current and potential characteristics of these anodic and cathodic fentanyl peaks, generated using two CSWV cycles, thus leads to a distinct electrochemical signature. This CSWV profile facilitates rapid (one minute) identification of the target opioid at micromolar concentrations in the presence of other cutting agents commonly found in illicit drug formulations. The new protocol thus holds considerable promise for rapid decentralized fentanyl detection at the ‘point of need’.

0

Porous materials, including metal-organic frameworks (MOFs), are known to undergo structural changes when subjected to applied hydrostatic pressures that are both fundamentally interesting and practically relevant. With the rich structural diversity of MOFs, the development of design rules to better understand and enhance the mechanical stability of MOFs is of paramount importance. In this work, the compressibilities of seven MOFs belonging to two topological families (representing the most comprehensive study of this type to date) were evaluated using in situ synchrotron X-ray powder diffraction of samples within a diamond anvil cell. Judicious selection of these materials, representing widely-studied classes of MOFs, provides broadly applicable insight into the rigidity and compression of hybrid materials. Analysis of these data reveals that the bulk modulus depends on several structural parameters (e.g. void fraction and linker length). Furthermore, we find that lattice distortions play a major role in the compression of MOFs. This study is an important step toward developing a predictive model of the structural variables that dictate the compressibility of porous materials.

0

Current understanding of the health risks and adverse effects upon exposure to fine particles is premised on the direct association of particles with target organs, particularly the lung; however, fine-particle exposure has also been found to have detrimental effects on sealed cavities distant to the portal-of-entry, such as joints. Moreover, the fundamental toxicological issues have been ascribed to the direct toxic mechanisms, in particular, oxidative stress and pro-inflammatory responses, without exploring the indirect mechanisms, such as compensated, adaptive, and secondary effects. In this review, we recapitulate the current findings regarding the detrimental effects of fine-particle exposure on joints, the surrounding cells and microenvironment, as well as their deteriorating impact on the progression of arthritis. We also elaborate the likely molecular mechanisms underlying the particle-induced detrimental influence on joints, not limited to direct toxicity, but also considering the other indirect mechanisms. Due to the similarities between fine air particles and engineered nanomaterials, we compare the toxicities of engineered nanomaterials to those of fine air particles. Arthritis and joint injuries are prevalent, particularly in the elderly population. Considering the severity of global exposure to fine particles and limited studies assessing the detrimental effects of fine-particle exposure on joints and arthritis, this review aims to appeal to a broad interest and to promote more research efforts in this field.

0

The first two cage based crystalline covalent organic frameworks, cage-COF-1 and cage-COF-2, were constructed from a prism-like three-aldehyde-containing molecular cage. The cage contains two horizontal phloroglucinol and three vertical triazine moieties forming three identical V-shaped cavities. By reacting with p-phenylenediamine and 4,4'-biphenyldiamine, the two cage-COFs were formed with a hexagonal skeleton and possess a unique structure. Due to the pillared cage nodes, the linkers are hanging with their π-surfaces but not C-H sites exposed to the pore, and enjoy certain rotational dynamics as suggested by 13C CP/MAS NMR. The anti-direction of the diimine linkages leads to rippled layers which pack in unique ABC mode through alternate stacking of the cage twosided faces in both AB and AC layers. Such packing forms trigonal channels along c axis which are interconnected in ab plane due to the large open space created across the hanging linkers, resembling the porous characteristics of 3D COFs. The cage-COFs have a permanent porosity and can adsorb CO2 facilitated by the intrinsic cage cavities that serve as prime adsorption sites. The unprecedented cage-COFs not only merge the borderline of 2D and 3D COFs, but also bridge porous organic cages to extended crystalline organic frameworks.

0

The analysis of lipid droplets (LDs) by mass spectrometry (MS) at the single LD level is still an analytical challenge. In this work, we developed a novel technique termed in-tip solvent microextraction mass spectrometry for the separation and profiling of phosphatidylcholines and triglycerides within a single LD. This method has been successfully used to analyze LDs in mammalian cells and to compare the profiles of triglycerides and phosphatidylcholines in LDs induced at different condi-tions. Our method has the potential to be applied to such fields as fundamental lipid biology, to further our understanding on the mechanisms of lipid production, lipid packaging, and their pathophysiological roles.