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Hepatolithiasis is a rare condition requiring multidisciplinary treatment approach. In this case report we present a case of multiple hepatolithiasis successfully treated with right hepatectomy. A 54 years-old asymptomatic female with previous history of hepaticojejunostomy for recurrent CBD stone was diagnosed with hepatolithiasis during routine follow-up. Hepatolithiasis has multifactorial causation one of which is thought to be previous biliary surgery. This case report highlights the importance of routine ultrasound imaging during follow-up of the patient with history of previous biliary surgery for early detection of hepatolithiasis thus, mitigating further complications., (© 2024 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

A myocardial infarction (MI), commonly called a heart attack, results in the death of cardiomyocytes (CMs) in the heart. Tissue engineering provides a promising strategy for the treatment of MI, but the maturation of human engineered cardiac tissue (hECT) still requires improvement. Conductive polymers and nanomaterials have been incorporated into the extracellular matrix to enhance the mechanical and electrical coupling between cardiac cells. Here we report a simple approach to incorporate gold nanorods (GNRs) into the fibrin hydrogel to form a GNR-fibrin matrix, which is used as the major component of the extracellular matrix for forming a 3D hECT construct suspended between two flexible posts. The hECTs made with GNR-fibrin hydrogel showed markers of maturation such as higher twitch force, synchronous beating activity, sarcomere maturation and alignment, t-tubule network development, and calcium handling improvement. Most importantly, the GNR-hECTs can survive over 9 months. We envision that the hECT with GNRs holds the potential to restore the functionality of the infarcted heart.

Glass nanopipettes have gained widespread use as a versatile single-entity detector in chemical and biological sensing, analysis, and imaging. Its advantages include low cost, easy accessibility, simplicity of use, and high versatility. However, conventional nanopipettes based on the volume exclusion mechanism have limitations in detecting small biomolecules due to their small volume and high mobility in aqueous solution. To overcome this challenge, we have employed a novel approach by capitalizing on the strong nanoconfinement effect of nanopipettes. This is achieved by utilizing both the hard confinement provided by the long taper nanopipette tip at the cis side and the soft confinement offered by the hydrogel at the trans side. Through this approach, we have effectively slowed down the exit motion of small molecules, allowing us to enrich and jam them at the nanopipette tip. Consequently, we have achieved high throughput detection of small biomolecules with sizes as small as 1 nm, including nucleoside triphosphates, short peptides, and small proteins with excellent signal-to-noise ratios. Furthermore, molecular complex formation through specific intermolecular interactions, such as hydrogen bonding between closely spaced nucleotides in the jam-packed nanopipette tip, has been detected based on the unique ionic current changes.

Plasmonic molecular junctions can harvest visible light and effectively catalyze chemical reactions. The strong light field concentrated in the plasmonic junction also enables the application of surface enhanced Raman spectroscopy (SERS) to probe the catalyzed chemical reactions in situ and in real time down to single-molecule resolution. The benzyl radical produced from the aromatic methyl group through the dehydrogenation reaction is an important precursor for a large variety of reactions. Here, we used time-resolved SERS to conduct a mechanistic study of the plasmon-driven dehydrogenation reaction of the aromatic methyl group under ambient conditions under the illumination of red light on the apex of a gold nanoelectrode. Transient spectral changes with intensity bursts are frequently observed. Based on density functional theory and picocavity based local electric field enhancement calculations, they result from the plasmon mediated dehydrogenation reaction of aromatic methyl groups. The dehydrogenation reaction produces a benzyl radical, which is consequently converted to a benzyl anion. The benzyl anion is stabilized through strong interactions with gold, leading to the formation of dynamic gold adatoms and picocavities. In addition to the benzyl anion, we found spectral evidence that the benzyl radical generates dimers through a self-reaction. Furthermore, we demonstrated that the dehydrogenation reaction could be facially modulated by changing the electrode potential, which is attributed to the modulated inductive effect., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

MoS 2 nanoribbons have attracted increased interest due to their properties, which can be tailored by tuning their dimensions. Herein, the growth of MoS 2 nanoribbons and triangular crystals formed by the reaction between films of MoOx (22 nanoribbons arising from distinct contributions from the single-layer edges and multilayer core. Nanoscale imaging reveals a blue-shifted exciton emission of the monolayer edge compared to the isolated MoS 2 monolayers due to built-in local strain and disorder. We further report on an ultrasensitive photodetector made of a single MoS 2 nanoribbon with a responsivity of 8.72 × 10 2  A W -1 at 532 nm, among the highest reported up-to-date for single-nanoribbon photodetectors. These findings can inspire the design of MoS 2 semiconductors with tunable geometries for efficient optoelectronic devices., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Plasmonic metal nanostructures are essential for plasmon-mediated chemical reactions (PMCRs) and surface-enhanced Raman spectroscopy (SERS). The nanostructures are commonly made from the coinage metals gold and silver. Copper (Cu) is less used mainly due to the difficulties in fabricating stable nanostructures. However, Cu is an attractive option with its strong plasmonic properties, high catalytic activities, and relatively cheap price. Herein, we fabricated tunable, reliable, and efficient Cu nanoelectrodes (CuNEs). Using time-resolved electrochemical SERS, we have comprehensively studied the reversible chemical transformations between aromatic amine and nitro groups modified on the CuNE surface. Their PMCRs are well-controlled by changing the surface roughness, the oxidation states of Cu, and the applied electrode potential. We thus demonstrate that the Cu nanostructures enable better investigations in the interplays between PMCR, electrochemistry, and Cu catalysis., (© 2023 Wiley-VCH GmbH.)

Chemical vapor deposition (CVD) has been established as a versatile route for the large-scale synthesis of transition metal dichalcogenides, such as tungsten disulfide (WS 2 ). Yet, the precursor composition's role on the CVD process remains largely unknown and remains to be explored. Here, we employ Pulsed Laser Deposition (PLD) in a two-stage approach to tune the oxygen content in the tungsten oxide (WO 3- x ) precursors and demonstrate the presence of oxygen vacancies in the oxide films leads to a more facile conversion from WO 3- x to WS 2 . Using a joint study based on ab initio density functional theory (DFT) calculations and experimental observations, we unravel that the oxygen vacancies in WO 3- x can serve as niches through which sulfur atoms enter the lattice and facilitate an efficient conversion into WS 2 crystals. By solely modulating the precursor stoichiometry, the photoluminescence emission of WS 2 crystals can be significantly enhanced. Atomic resolution scanning transmission electron microscopy imaging (STEM) reveals that tungsten vacancies are the dominant intrinsic defects in mono- and bilayers WS 2 . Moreover, bi- and multilayer WS 2 crystals derived from oxides with a high V 0 content exhibit dominant AA'/AB or AA(A…) stacking orientations. The atomic resolution images reveal local strain buildup in bilayer WS 2 due to competing effects of complex grain boundaries. Our study provides means to tune the precursor composition to control the lateral growth of TMDs while revealing insights into the different pathways for forming grain boundaries in bilayer WS 2 .

Nepal exhibits a tuberculosis (TB) incidence rate that is comparable to neighbouring high TB incidence countries. In addition, it records >500 cases of multi-drug resistant (MDR) TB each year. The objective of this study was to perform whole-genome bioinformatic analysis on MDR-TB isolates from Nepal (n = 19) to identify the specific mutations underlying their phenotypic resistance. In addition, we examined the dominant genotype among the Nepal MDR-TB isolates, the East-Asian Beijing sub-lineage, to determine its relatedness to a panel of 1274 genomes of international strains available from public databases. These analyses provided evidence that the XDR-TB isolates in our collection were not derived from importation of primary XDR-TB to Nepal but were more likely the result of acquisition of second-line drug resistance in Nepal. Resistance to fluoroquinolones was detected among a high proportion of the Nepal isolates. This has implications for the management of TB, including appropriate antimicrobial stewardship and susceptibility testing for fluoroquinolones and other second-line TB drugs, to minimise the development of XDR-TB among Nepal TB cases., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

ReS 2 exhibits strong anisotropic optical and electrical responses originating from the asymmetric lattice. Here, we show that the anisotropy of monolayer (1L) ReS 2 in optical scattering and electrical transport can be practically erased by lattice engineering via lithium (Li) treatment. Scanning transmission electron microscopy revealed that significant strain is induced in the lattice of Li-treated 1L-ReS 2 , due to high-density electron doping and the resultant formation of continuous tiling of nanodomains with randomly rotating orientations of 60°, which produced a nearly isotropic response of polarized Raman scattering and absorption of Li-treated 1L-ReS 2 . With Li treatment, the in-plane conductance of 1L-ReS 2 increased by an order of magnitude, and its angle dependence became negligible. Our result that the asymmetric phase was converted into the isotropic phase by electron injection could significantly expand the optoelectronic applications of polymorphic two-dimensional transition metal dichalcogenides.

An effective and reversible tuning of the intensity of surface-enhanced Raman scattering (SERS) of nonelectroactive molecules at nonresonance conditions by electrochemical means has been developed on plasmonic molecular nanojunctions formed between Au@Ag core-shell nanoparticles (NPs) and a gold nanoelectrode (AuNE) modified with a self-assembled monolayer. The Au@Ag nanoparticle on nanoelectrode (NPoNE) structures are formed in situ by the electrochemical deposition of Ag on AuNPs adsorbed on the AuNE and can be monitored by both the electrochemical current and SERS signals. Instead of introducing molecular changes by the applied electrode potential, the highly effective SERS intensity tuning was achieved by the chemical composition transformation of the ultrathin Ag shell from metallic Ag to insulating AgCl. The electrode potential-induced electromagnetic enhancement (EME) tuning in the Au@Ag NPoNE structure has been confirmed by finite-difference time-domain simulations. Moreover, the specific Raman band associated with Ag-molecule interaction can also be tuned by the electrode potential. Therefore, we demonstrated that the electrode potential could effectively and reversibly modulate both EME and chemical enhancement in Au@Ag NPoNE structures.

This project was aimed to formulate and characterize mucoadhesive buccal tablets of aceclofenac, utilizing different proportions of three polymers carbopol 934, hydroxypropyl methylcellulose, and sodium carboxymethylcellulose. Twelve batches of buccoadhesive aceclofenac were prepared by the direct compression method. The compressed tablets were then evaluated for physicochemical parameters such as hardness, thickness, weight variation, drug content, friability, swelling index, surface pH, and ex vivo mucoadhesion. In vitro dissolution test was conducted for 12 h according to Indian Pharmacopeia 2018, using the rotating paddle method in phosphate buffer of pH 7.4. Physiochemical parameters like weight variation (231.25-268.75 mg), hardness (8.32-11.56 kg), friability (0.04-0.2%), diameter (9.00 mm), thickness (3.8-4.05 mm), and drug content ((97.67-102.25%) were within the acceptable limit as per Indian Pharmacopeia 2018. The swelling index was reported to be in the range of 112.93-450.19%, at 8 h. The surface pHs of all the batches were in between 6.72 to 6.96. The mucoadhesive strengths (40.5-50 g) varied with the change in polymer concentrations especially of carbopol 934. The dissolution profile of all the batches varied greatly, with a maximum release of 109.41% (in batch 12 at 6 h) to a minimum release of 44.82% (in batch 3 at 12 h). Among them, only batch 1 ensured sustained and effective drug release (88.34% at 12 h) with appropriate swelling index (112.93%) and mucoadhesive strength (40 g). Fourier Transform Infrared Spectroscopy analysis showed no evidence of drug excipients interaction. Hence, the results concluded that buccal mucoadhesive aceclofenac tablets can be formulated. Furthermore, the property of the tablet not only depends on the concentration but also the behavior of the polymers used., Competing Interests: The authors declare no conflict of interest., (© 2021 The Authors. Published by Elsevier Ltd.)

Magneto-electric nanoparticles (MENPs), composed of a piezoelectric shell and a ferromagnetic core, exhibited enhanced cell uptake and controlled drug release due to the enhanced localized electric field (surface charge/potential) and the generation of acoustics, respectively, upon applying alternating current (AC) magnetic (B)-field stimulation. This research, for the first time, implements an electrochemical single-entity approach to probe AC B-field induced strain mediated surface potential enhancement on MENP surface. The surface potential changes at the single-NP level can be probed by the open circuit potential changes of the floating carbon nanoelectrode (CNE) during the MENP-CNE collision events. The results confirmed that the AC B-field (60 Oe) stimulation caused localized surface potential enhancement of MENP. This observation is associated with the presence of a piezoelectric shell, whereas magnetic nanoparticles were found unaffected under identical stimulation.

Background: Acoustic Voice Quality Index (AVQI) has been reported to be a sensitive tool for discriminating between the normal and dysphonic voices, however, there is a dearth of research focused on investigating the diagnostic accuracy of AVQI in discriminating across the perceptual categories of dysphonia severity ie, slight, moderate, and severe. Hence, the present study is a preliminary attempt to document the AVQI across the degrees of dysphonia severity and to verify whether the AVQI can discriminate across these degrees of perceptual dysphonia severity., Method: A total of 71 dysphonic samples extracted from the clinical database of the institute and 19 prospectively recorded normophonic samples consisting of sustained vowel /a/ and a sentence from a standardized Kannada passage served as input data. These 90 samples were categorized into four categories based on the overall grade of perceptual dysphonia (G) as normal, slight, moderate, or severe by three experienced speech language pathologists in a randomized and double-blinded manner, which served as the ground truth. The AVQI was calculated from the samples using Praat version 6.0.40 and the AVQI script version 2.03., Results: The Spearman's correlation test revealed a positive correlation between the G and the AVQI (r = 0.67; P < 0.001). The Receiver Operating Characteristics analysis revealed that the AVQI could accurately discriminate across the perceptual subcategories of dysphonia., Conclusions: The results of the present study revealed that AVQI is a robust multiparametric measure which can accurately discriminate across the subcategories of the perceptual dysphonia severity with reasonable precision. Further, the AVQI is also shown to be promising in evaluating the signals with higher levels of aperiodicity such as severe hoarse voice quality., (Copyright © 2019. Published by Elsevier Inc.)

Among the layered two dimensional semiconductors, molybdenum disulfide (MoS2) is considered to be an excellent candidate for applications in optoelectronics and integrated circuits due to its layer-dependent tunable bandgap in the visible region, high ON/OFF current ratio in field-effect transistors (FET) and strong light-matter interaction properties. In this study, using multi-terminal measurements, we report high broadband photocurrent response (R) and external quantum efficiency (EQE) of few-atomic layered MoS2 phototransistors fabricated on a SiO2 dielectric substrate and encapsulated with a thin transparent polymer film of Cytop. The photocurrent response was measured using a white light source as well as a monochromatic light of wavelength λ = 400 nm-900 nm. We measured responsivity using a 2-terminal configuration as high as R = 1 × 103 A W-1 under white light illumination with an optical power Popt = 0.02 nW. The R value increased to 3.5 × 103 A W-1 when measured using a 4-terminal configuration. Using monochromatic light on the same device, the measured values of R were 103 and 6 × 103 A W-1 under illumination of λ = 400 nm when measured using 2- and 4-terminal methods, respectively. The highest EQE values obtained using λ = 400 nm were 105% and 106% measured using 2- and 4-terminal configurations, respectively. The wavelength dependent responsivity decreased from 400 nm to the near-IR region at 900 nm. The observed photoresponse, photocurrent-dark current ratio (PDCR), detectivity as a function of applied gate voltage, optical power, contact resistances and wavelength were measured and are discussed in detail. The observed responsivity is also thoroughly studied as a function of contact resistance of the device.

The essential oils (EOs) of three Caprifoliaceae species, the Eurasiatic Valeriana officinalis (Vo), the Himalayan Valeriana jatamansi (Vj) and Nardostachys jatamansi (Nj), are traditionally used to treat neurological disorders. Roots/rhizomes micromorphology, DNA barcoding and EOs phytochemical characterization were carried out, while biological effects on the nervous system were assessed by acetylcholinesterase (AChE) inhibitory activity and microelectrode arrays (MEA). Nj showed the highest inhibitory activity on AChE (IC 50 67.15 μg/mL) followed by Vo (IC 50 127.30 μg/mL) and Vj (IC 50 246.84 μg/mL). MEA analyses on rat cortical neurons, carried out by recording mean firing rate (MFR) and mean bursting rate (MBR), revealed stronger inhibition by Nj (IC 50 18.8 and 11.1 μg/mL) and Vo (16.5 and 22.5 μg/mL), compared with Vj (68.5 and 89.3 μg/mL). These results could be related to different EO compositions, since sesquiterpenes and monoterpenes significantly contribute to the observed effects, but the presence of oxygenated compounds such as aldehydes and ketones is a discriminating factor in determining the order of potency. Our multidisciplinary approach represents an important tool to avoid the adulteration of herbal drugs and permits the evaluation of the effectiveness of EOs that could be used for a wide range of therapeutic applications.

Evaluating the risk of colorectal metachronous adenoma (MA), which is a precancerous lesion, is necessary for metachronous colorectal cancer (CRC) precaution among CRC patients who had underwent surgical removal of their primary tumor. Here, discovery cohort ( n = 41) and validation cohort ( n = 45) of CRC patients were prospectively enrolled in this study. Mucosal and fecal samples were used for gut microbiota analysis by sequencing the 16S rRNA genes. Significant reduction of microbial diversity was noted in MA ( P < 0.001). A signature defined by decreased abundance of eight genera and increased abundance of two genera strongly correlated with MA. The microbiota-based random forest (RF) model, established utilizing Escherichia-Shigella , Acinetobacter together with BMI in combination, achieved AUC values of 0.885 and 0.832 for MA, predicting in discovery and validation cohort, respectively. The RF model was performed as well for fecal and tumor adjacent mucosal samples with an AUC of 0.835 and 0.889, respectively. Gut microbiota profile of MA still existed in post-operative cohort patients, but the RF model could not be performed well on this cohort, with an AUC of 0.61. Finally, we introduced a risk score based on Escherichia-Shigella , Acinetobacter and BMI, and synchronous-adenoma achieved AUC values of 0.94 and 0.835 in discovery and validation cohort, respectively. This study presented a comprehensive landscape of gut microbiota in MA, demonstrated that the gut microbiota-based models and scoring system achieved good ability to predict the risk for developing MA after surgical resection. Our study suggests that gut microbiota is a potential predictive biomarker for MA., (Copyright © 2020 Liu, Geng, Liu, Jin, Yan, Zhao, Wang, Guo, Ghimire and Wei.)

This paper reports molecular diffusion behavior in two bolaamphiphile-based organic nanotubes having inner carboxyl groups with different inner dimeters (10 and 20 nm) and wall structures, COOH-ONT 10nm and COOH-ONT 20nm , using imaging fluorescence correlation spectroscopy (imaging FCS). The results were compared to those previously obtained in a similar nanotube with inner amine groups (NH 2 -ONT 10nm ). COOH-ONT 10nm , as with NH 2 -ONT 10nm , were formed from a rolled bolaamphiphile layer incorporating triglycine moieties, whereas COOH-ONT 20nm consisted of four stacks of triglycine-free bolaamphiphile layers. Imaging FCS measurements were carried out for anionic sulforhodamine B (SRB), zwitterionic/cationic rhodamine B (RB), and cationic rhodamine-123 (R123) diffusing within ONTs (1-9 μm long) at different pH (3.4-8.4) and ionic strengths (1.6-500 mM). Diffusion coefficients ( D ) of these dyes in the ONTs were very small (0.01-0.1 μm 2 /s), reflecting the significant contributions of molecule-nanotube interactions to diffusion. The D of SRB was larger at higher pH and ionic strength, indicating the essential role of electrostatic repulsion that was enhanced by the deprotonation of the inner carboxyl groups. Importantly, the D of SRB was virtually independent of nanotube inner diameter and wall structure, indicating the diffusion of the hydrophilic molecule was controlled by short time scale adsorption/desorption processes onto the inner surface. In contrast, pH effects on D were less clear for relatively hydrophobic R123 and RB, suggesting the significant contributions of non-Coulombic interactions. Interestingly, the diffusion of these molecules in COOH-ONT 20nm was slower than in COOH-ONT 10nm . Slower diffusion in COOH-ONT 20nm was attributable to relatively efficient partitioning of the hydrophobic dyes into the bolaamphiphile layers, which was reduced in COOH-ONT 10nm due to the stabilization of its layer by polyglycine-II-type hydrogen bonding networks. These results show that, by tuning the bolaamphiphile structures and their intermolecular interactions, unique environments can be created within the nanospaces for enhanced molecular separations and reactions.