We identified wide variation in surgery for trapeziometacarpal osteoarthritis among surgeons in the United States, with 42% performing no surgery, a median rate of surgery of 1.9/year, and 2% performed more than 30 procedures annually, representing 15% of all surgical procedures for TMC arthritis.

BACKGROUND: Thyroid microcarcinoma (TMC) incidence has significantly increased in recent decades. The rates of lymph node metastasis extrathyroidal extension have been significantly different in patients with TMC ≤5 mm versus those with size >5 mm. The current analysis aimed to examine the clinicopathologic features of TMC measuring <5 mm and to compare them with those of TMC ≥5 mm.
METHODS: A total of 273 patients with TMC confirmed by histological examination from December 2020 to May 2021 were enrolled in Bach Mai Hospital, Hanoi, Vietnam. Unconditional logistic regression models were used to determine the association between clinicopathological factors and tumor size, central lymph node metastasis and extrathyroidal extension.
RESULTS: We found 212/273 patients (77.7%) were diagnosed incidentally. The majority of patients were female (87.5%) and had a mean age of 44.2 years. The mean tumor size (±standard deviation (SD)) was 5.72 ± 2.33 mm. Most of the patients were also diagnosed with papillary TMC. Multifocal and bilateral lesions accounted for 13.2% and 12.1%, respectively. The extrathyroidal invasion was observed in 14.7% (40 patients), while 24.5% (67 patients) were those with central lymph node metastases. The rate of extrathyroidal extension in patients with tumor size ≥5 mm was significantly higher than in patients with tumor size <5 mm (odds ratio (OR) = 4.98; 95% confidence interval (CI): 1.48-16.70; p = 0.004). Patients with body mass index (BMI) <23 kg/m2 were found to be protected against the odds of extrathyroidal extension (OR = 0.38, 95% CI: 0.19-0.75; p = 0.004) compared to those with BMI ≥23 kg/m2. In univariable mode, central lymph node metastasis was positively associated with the odds of the presence of extrathyroidal extension (OR = 2.70, 95% CI: 1.34-5.45; p = 0.004). In the multivariable model, central lymph node metastasis was also associated with the presence of extrathyroidal extension (OR = 2.507, 95% CI: 1.194-5.264; p = 0.017). Univariate analysis demonstrated that tumor size ≥5 mm (OR = 2.04; 95% CI: 1.01-4.17; p = 0.047) and extrathyroidal extension (OR = 2.71; 95% CI: 1.34-5.45; p = 0.004) were risk factors of central cervical lymph node metastasis. In multivariable models, the extrathyroidal extension was associated with central lymph metastasis.
CONCLUSIONS: TMC <5 mm tumor size is less likely to have aggressive characteristics, including extrathyroidal extension, than a TMC ≥5 mm. Long-term follow-up studies are thus warranted to investigate the factors in the prognosis of TMC.

In multicellular lives, the differentiation of stem cells and progenitor cells is often accompanied by a transition from glycolysis to mitochondrial oxidative phosphorylation (OXPHOS). However, the underlying mechanism of this metabolic transition remains largely unknown. In this study, we investigate the role of mechanical stress in activating OXPHOS during differentiation of the female germline cyst in Drosophila. We demonstrate that the surrounding somatic cells flatten the 16-cell differentiating cyst, resulting in an increase of the membrane tension of germ cells inside the cyst. This mechanical stress is necessary to maintain cytosolic Ca2+ concentration in germ cells through a mechanically activated channel, transmembrane channel-like. The sustained cytosolic Ca2+ triggers a CaMKI-Fray-JNK signaling relay, leading to the transcriptional activation of OXPHOS in differentiating cysts. Our findings demonstrate a molecular link between cell mechanics and mitochondrial energy metabolism, with implications for other developmentally orchestrated metabolic transitions in mammals.

OSCA/TMEM63s form mechanically activated (MA) ion channels in plants and animals, respectively. OSCAs and related TMEM16s and transmembrane channel-like (TMC) proteins form homodimers with two pores. Here, we uncover an unanticipated monomeric configuration of TMEM63 proteins. Structures of TMEM63A and TMEM63B (referred to as TMEM63s) revealed a single highly restricted pore. Functional analyses demonstrated that TMEM63s are bona fide mechanosensitive ion channels, characterized by small conductance and high thresholds. TMEM63s possess evolutionary variations in the intracellular linker IL2, which mediates dimerization in OSCAs. Replacement of OSCA1.2 IL2 with TMEM63A IL2 or mutations to key variable residues resulted in monomeric OSCA1.2 and MA currents with significantly higher thresholds. Structural analyses revealed substantial conformational differences in the mechano-sensing domain IL2 and gating helix TM6 between TMEM63s and OSCA1.2. Our studies reveal that mechanosensitivity in OSCA/TMEM63 channels is affected by oligomerization and suggest gating mechanisms that may be shared by OSCA/TMEM63, TMEM16, and TMC channels.

The spine is the most common site of bone metastases. Many cancer patients will ultimately develop spinal metastatic disease with symptomatic epidural spinal cord compression. At present, the main treatment for cervical spine tumors is surgical resection combined with postoperative radiotherapy. Implant materials for cervical spine anterior column reconstruction need to meet amounts of different properties, such as biocompatibility, bioactivity and the ability to maintain long-term mechanical strength. The selection of different materials determines the surgical efficacy and prognosis of patients to a certain extent. This article provides an overview of a variety of implant materials used for anterior column reconstruction after cervical spine tumor resection, introduces and analyzes their properties, advantages, disadvantages, derivatives, and applications in clinical practice, and looks forward to the future development of implant materials.

Chitosan is used in several fields such as medicine, environment and advanced functional materials. The N-alkylation of chitosan into N,N,N-trimethylchitosan (TMC) allows to improve some properties. The current quantification methods of the degree of quaternization (DQ) like titration and 1H NMR spectroscopy require the solubilization of TMC. In this study, a solid-state 13C NMR quantification method was developed for insoluble TMCs. For this purpose, four TMC derivatives acting as reference were synthesized and their degrees of quaternization, N,N-dimethylation (DD) and acetylation (DA) were determined in solution by 1H NMR. CP-MAS 13C NMR spectra of those derivatives were deconvolved with Lorentz functions. Several ratios of the 13C NMR peak areas were correlated with the degrees of substitution obtained in 1H NMR. The best quantification method of DQ involved the correlation of the carbon signal of methyl groups. The method was also applied for the determination of the DD and DA of TMCs.

The structural integrity of a dentin matrix that has been demineralized by the clinical use of etchants or calcium-depleting endodontic irrigants, such as endodontic ethylenediaminetetraacetic acid (EDTA), is often deteriorated due to the collagenolytic activities of reactivated endogenous enzymes as well as the infiltration of extrinsic bacteria. Therefore, the biomodification of dentin collagen with improved stability and antibacterial activity holds great promise in conservative dentistry. The purpose of this study was to evaluate the effects of the combined application of trimethylated chitosan (TMC) and 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride (EDC) on the biostability and antibacterial activity of the demineralized dentin collagen matrix. The morphological changes in the collagen matrix were observed by scanning electron microscopy (SEM), the amount of TMC adsorbed on the collagen surface was detected by X-ray photoelectron spectroscopy, and the elastic modulus was measured by a three-point bending device. Dry weight loss and amino acid release were detected to evaluate its anti-collagenase degradation performance. The antibacterial performance was detected by confocal microscopy. The TMC-treated group had less collagen space and a more compact collagen arrangement, while the untreated group had a looser collagen arrangement. The combined application of TMC and EDC can increase the elastic modulus, reduce the loss of elastic modulus, and result in good antibacterial performance. The current study proved that a dentin collagen matrix biomodified by TMC and EDC showed improved biodegradation resistance and antibacterial activities.

The ability of living organisms to detect mechanical force originates from mechanotransduction ion channels, which convert membrane tension into electrical or chemical signals that are transmitted to the brain. A variety of studies on touch and sound perception in both vertebrates and invertebrates have broadened our understanding of mechanotransduction and identified promising candidates for mechanotransduction ion channels. Here, we discussed the physiological properties of mechanotransduction ion channels in hearing and touch, the identification of their molecular entities, and recent structural studies providing insights to their gating mechanisms in force sensing. We present an updated review of the evidence supporting several candidates, including NOMPC, Brv1, and TMC channels, as mechanotransduction ion channels and highlight their qualifications satisfying the specific criteria proposed for a mechanotransducer.

Unlike olfaction, taste, touch, vision, and proprioception, which are widespread across animal phyla, hearing is found only in vertebrates and some arthropods. The vast majority of invertebrate species are thus considered insensitive to sound. Here, we challenge this conventional view by showing that the earless nematode C. elegans senses airborne sound at frequencies reaching the kHz range. Sound vibrates C. elegans skin, which acts as a pressure-to-displacement transducer similar to vertebrate eardrum, activates sound-sensitive FLP/PVD neurons attached to the skin, and evokes phonotaxis behavior. We identified two nAChRs that transduce sound signals independently of ACh, revealing an unexpected function of nAChRs in mechanosensation. Thus, the ability to sense airborne sound is not restricted to vertebrates and arthropods as previously thought, and might have evolved multiple times independently in the animal kingdom, suggesting convergent evolution. Our studies also demonstrate that animals without ears may not be presumed to be sound insensitive.

Transition metal dichalcogenides (TMDs), transition metal carbides (TMCs), and transition metal oxides (TMOs) have been widely investigated for electrocatalytic applications owing to their abundant active sites, high stability, good conductivity, and various other fascinating properties. Therefore, the synthesis of composites of TMDs, TMCs, and TMOs is a new avenue for the preparation of efficient electrocatalysts. Herein, we propose a novel low-cost and facile method to prepare TMD-TMC-TMO nano-hollow spheres (WS2-WC-WO3 NH) as an efficient catalyst for the hydrogen evolution reaction (HER). The crystallinity, morphology, chemical bonding, and composition of the composite material were comprehensively investigated using X-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy. The results confirmed the successful synthesis of the WS2-WC-WO3 NH spheres. Interestingly, the presence of nitrogen significantly enhanced the electrical conductivity of the hybrid material, facilitating electron transfer during the catalytic process. As a result, the WS2-WC-WO3 NH hybrid exhibited better HER performance than the pure WS2 nanoflowers, which can be attributed to the synergistic effect of the W-S, W-C, and W-O bonding in the composite. Remarkably, the Tafel slope of the WS2-WC-WO3 NH spheres was 59 mV dec-1, which is significantly lower than that of the pure WS2 NFs (82 mV dec-1). The results also confirmed the unprecedented stability and superior electrocatalytic performance of the WS2-WC-WO3 NH spheres toward the HER, which opens new avenues for the preparation of low-cost and highly effective materials for energy conversion and storage applications.