Comparative Efficacy and Acceptability of Endoscopic Methods for Rectal Neuroendocrine Neoplasms with Low Malignant Potential: A Network Meta-analysis.

BACKGROUND/AIMS:  Although endoscopic resection is an effective treatment of rectal neuroendocrine neoplasms (R-NENs) with low malignant potential, there is no consensus on the most recommended endoscopic method. This study aimed to assess the efficacy and acceptability of different endoscopic treatments for R-NENs with low malignant potential. MATERIALS AND METHODS:  We searched databases for studies on treatments of R-NENs using endoscopic resection. These studies comprised techniques such as endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), modified endoscopic mucosal resection (EMRM), modified endoscopic submucosal dissection (ESDM), and transanal endoscopic microsurgery (TEM). The primary outcomes assessed were histological complete resection (HCR). RESULTS:  Overall, 38 retrospective studies (3040 R-NENs) were identified. Endoscopic mucosal resection with a cap (EMRC), endoscopic mucosal resection with ligation (EMRL), ESD, ESDM, and TEM demonstrated higher resectability than did EMR in achieving HCR. Endoscopic mucosal resection, EMRC, EMRL, EMRP, EMRD, and EMRU required shorter operation times than did ESD. Endoscopic mucosal resection, EMRC, ESDM, and TEM incurred lower risks than did ESD. CONCLUSION:  Regarding R-NENs <20 mm with low malignant potential, ESD could be used as the primary treatment. However, TEM may be more effective if supported by economic conditions and hospital facility. With respect to R-NENs <16 mm with low malignant potential, EMRL could be used as the primary treatment. In regard to R-NENs <10 mm with low malignant potential, EMRL, EMRC, and ESD could be used as the primary treatment. However, EMRL and EMRC might be better when operational difficulties and economic conditions were considered.

Local Application of Tanshinone IIA protects mesenchymal stem cells from apoptosis and promotes fracture healing in ovariectomized mice.

BACKGROUND: Elderly patients suffering from osteoporotic fractures are more susceptible to delayed union or nonunion, and their bodies then are in a state of low-grade chronic inflammation with decreased antioxidant capacity. Tanshinone IIA is widely used in treating cardiovascular and cerebrovascular diseases in China and has anti-inflammatory and antioxidant effects. We aimed to observe the antioxidant effects of Tanshinone IIA on mesenchymal stem cells (MSCs), which play important roles in bone repair, and the effects of local application of Tanshinone IIA using an injectable biodegradable hydrogel on osteoporotic fracture healing. METHODS: MSCs were pretreated with or without different concentrations of Tanshinone IIA followed by H2O2 treatment. Ovariectomized (OVX) C57BL/6 mice received a mid-shaft transverse osteotomy fracture on the left tibia, and Tanshinone IIA was applied to the fracture site using an injectable hydrogel. RESULTS: Tanshinone IIA pretreatment promoted the expression of nuclear factor erythroid 2-related factor 2 and antioxidant enzymes, and inhibited H2O2-induced reactive oxygen species accumulation in MSCs. Furthermore, Tanshinone IIA reversed H2O2-induced apoptosis and decrease in osteogenic differentiation in MSCs. After 4 weeks of treatment with Tanshinone IIA in OVX mice, the bone mineral density of the callus was significantly increased and the biomechanical properties of the healed tibias were improved. Cell apoptosis was decreased and Nrf2 expression was increased in the early stage of callus formation. CONCLUSIONS: Taken together, these results indicate that Tanshinone IIA can activate antioxidant enzymes to protect MSCs from H2O2-induced cell apoptosis and osteogenic differentiation inhibition. Local application of Tanshinone IIA accelerates fracture healing in ovariectomized mice.

Cryo-EM structure of human HCN3 channel and its regulation by cAMP.

HCN channels are important for regulating heart rhythm and nerve activity and have been studied as potential drug targets for treating depression, arrhythmia, nerve pain, and epilepsy. Despite possessing unique pharmacological properties, HCN channels share common characteristics in that they are activated by hyperpolarization and modulated by cAMP and other membrane lipids. However, the mechanisms of how these ligands bind and modulate HCN channels are unclear. In this study, we solved structures of full-length human HCN3 using cryo-EM and captured two different states, including a state without any ligand bound and a state with cAMP bound. Our structures reveal the novel binding sites for cholesteryl hemisuccinate in apo state and show how cholesteryl hemisuccinate and cAMP binding cause conformational changes in different states. These findings explain how these small modulators are sensed in mammals at the molecular level. The results of our study could help to design more potent and specific compounds to influence HCN channel activity and offer new therapeutic possibilities for diseases that lack effective treatment.

An annular pulse forming line based on coaxial transmission lines.

The miniaturization, lightweight, and solidification of pulse forming lines (PFLs) are of prime significance during the evolution of pulsed power technology. In this paper, an all-solid-state annular pulse forming line (APFL) based on film-insulated coaxial transmission lines is developed to generate fast-rise time quasi-square pulses. First, a coiled coaxial transmission line (CCTL) comprised of multilayer polypropylene films with outstanding insulating properties is constructed. It can withstand direct current voltages up to 200 kV, with a cross section diameter of 7.4 mm. In addition, in order to turn the pulse transmission direction from circumferential to axial, a compact insulated terminal with a 90° bend structure is designed for CCTL. Although single terminal inductance can slow down the rising edge of the output pulse, their parallel connection in an APFL can weaken such an effect. The APFL, with a characteristic impedance of 2.95 Ω and a transmission time of 13 ns, is composed of three CCTLs with six terminals, which can run over 100 thousand times under the pulse voltage of 75 kV. Finally, 15 series APFL modules are employed to assemble a multi-stage PFL for the Tesla-type pulse generator. When charged to a voltage of 1 MV, the mixed PFL consisting of a coaxial line and the multi-stage PFL outputs quasi-square pulses with a voltage amplitude, rise time, and width of 510 kV, 4 ns, and 41.5 ns, respectively, and the fluctuation of the flat top is about 6%.

METTL14-Mediated m6a Modification of CDKN2A Promotes the Development of Retinoblastoma by Inhibiting the p53 Pathway.

The methyltransferase 14, N6-adenosine-methyltransferase subunit (METTL14) and Cyclin-dependent kinase inhibitor 2A (CDKN2A) have been identified as involved in the regulation of various cancer progression, while their mechanism and regulatory effect in retinoblastoma (RB) is still unclear. Cell colony formation, CCK-8 as well as Western blotting were used to evaluate the proliferation, apoptosis as well as p53 protein level of RB cell line. The METTL14 and CDKN2A levels were detected by qRT-PCR or Western blotting when METTL14 was up-regulated or CDKN2A was down-regulated. MeRIP and Pearson analysis were performed to confirm the regulatory relationship between METTL14 among CDKN2A. We found that the levels of CDKN2A and METTL14 were abundant in RB samples, as well as RB cells. METTL14 enhances N6-methyladenosine (m6A) modification of CDKN2A to upregulate its mRNA and protein levels. The proliferation of RB cells can be inhibited by silencing CDKN2A, which promotes apoptosis and p53 protein level. Furthermore, high-expression of METTL14 eliminated the anti-tumor effect of CDKN2A silencing in RB progression in vitro. CDKN2A is mediated by METTL14-m6A modified and restrains p53 pathway activation to accelerate the malignancy of RB. This points to the METTL14-m6A-CDKN2A-p53 pathway axis as a possible prospective target for the future RB treatment.

Mechanosensitive channels TMEM63A and TMEM63B mediate lung inflation-induced surfactant secretion.

Pulmonary surfactant is a lipoprotein complex lining the alveolar surface to decrease the surface tension and facilitate inspiration. Surfactant deficiency is often seen in premature infants and in children and adults with respiratory distress syndrome. Mechanical stretch of alveolar type 2 epithelial (AT2) cells during lung expansion is the primary physiological factor that stimulates surfactant secretion; however, it is unclear whether there is a mechanosensor dedicated to this process. Here, we show that loss of the mechanosensitive channels TMEM63A and TMEM63B (TMEM63A/B) resulted in atelectasis and respiratory failure in mice due to a deficit of surfactant secretion. TMEM63A/B were predominantly localized at the limiting membrane of the lamellar body (LB), a lysosome-related organelle that stores pulmonary surfactant and ATP in AT2 cells. Activation of TMEM63A/B channels during cell stretch facilitated the release of surfactant and ATP from LBs fused with the plasma membrane. The released ATP evoked Ca2+ signaling in AT2 cells and potentiated exocytic fusion of more LBs. Our study uncovered a vital physiological function of TMEM63 mechanosensitive channels in preparing the lungs for the first breath at birth and maintaining respiration throughout life.

Screening and evaluation of skin potential probiotic from high-altitude Tibetans to repair ultraviolet radiation damage.

Human skin microbes play critical roles in skin health and diseases. Microbes colonizing on the skin of Tibetans living in the high-altitude area for generations may have a stronger ability to resist the harsh environment, such as high ultraviolet radiation (UV). Isolation of a potential probiotic from Tibetans skin is beneficial for resistance of skin disease for humans in the world. In this study, the signature microbiota for Tibetan skin were characterized compared to low-altitude humans. Next, using culture-omics, 118 species were isolated. The culturability of high-altitude of Tibetan skin microbiome reached approximate 66.8%. Next, we found that one strain, Pantoea eucrina, had the greatest ability to repair UV damage to the skin as the lowest pathological score was observed in this group. Interestingly, another animal trial found this bacterium resisted UV rather than its metabolites. Using whole genome sequencing, this strain P. eucrina KBFS172 was confirmed, and its functions were annotated. It might involve in the metabolic pathway of carotenoid biosynthesis with anti-oxidative stress properties, which plays critical roles in UV-damage repair. In conclusion, we characterized the signature microbes of skin in high-altitude Tibetans, isolated a skin bacterium of Pantoea eucrina KBFS172 which could repair UV damage via involving the metabolic pathway of carotenoid biosynthesis. Our results provide a new potential skin probiotic for skin disease prevention or sunburn.

Efficacy of neoadjuvant therapy for lung squamous cell carcinoma and lung adenocarcinoma: A retrospective comparative study.

Preoperative neoadjuvant therapy is widely used in cancer treatment; however, its efficacy in different subtypes of non-small cell lung cancer (NSCLC) is unknown. The present study compared the clinical efficacy of preoperative neoadjuvant therapy for two major NSCLC subtypes. Patients with NSCLC who underwent preoperative neoadjuvant therapy between January 2016 and August 2022 were reviewed. Patients were stratified according to histology and treatment strategy. Retrospective analysis was performed by comparing the basic clinical characteristics of the patients, clinicopathological characteristics of the tumors, imaging data and pathological responses to treatment. A total of 36 cases of lung squamous cell carcinoma (LUSC) and 31 cases of lung adenocarcinoma (LUAD) were included. After neoadjuvant chemotherapy combined with immunotherapy, the pathological response rates were higher for patients with LUSC than LUAD, but there was no statistically significant difference between the two subgroups (P=0.06). However, the pathological complete response rates after neoadjuvant chemotherapy combined with immunotherapy were significantly higher for LUSC than those after chemotherapy alone (P=0.01). These preliminary findings suggested that preoperative chemotherapy combined with immunotherapy could improve the pathological response of patients, particularly in those with LUSC. The present study provided new insights into the treatment of NSCLC.

Role of glycosphingolipid biosynthesis coregulators in malignant progression of thymoma.

As the most common malignancy from mediastinum, the metabolic reprogramming of thymoma is important in its development. Nevertheless, the connection between the metabolic map and thymoma development is yet to be discovered. Thymoma was categorized into three subcategories by unsupervised clustering of molecular markers for metabolic pathway presentation in the TCGA dataset. Different genes and functions enriched were demonstrated through the utilization of metabolic Gene Ontology (GO) analysis. To identify the main contributors in the development of thymic malignancy, we utilized Gene Set Enrichment Analysis (GSEA), Gene Set Variation Analysis (GSVA), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The prognosis of thymoma was evaluated by screening the essential pathways and genes using GSVA scores and machine learning classifiers. Furthermore, we integrated the transcriptomics findings with spectrum metabolomics investigation, detected through LC-MS/MS, in order to establish the essential controller network of metabolic reprogramming during thymoma progression. The thymoma prognosis is related to glycosphingolipid biosynthesis-lacto and neolacto series pathway, of what high B3GNT5 indicate poor survival. The investigation revealed that glycosphingolipid charts have a significant impact on metabolic dysfunction and could potentially serve as crucial targets in the clinical advancement of metabolic therapy.

To Be or Not to Be an Ion Channel: Cryo-EM Structures Have a Say.

Ion channels are the second largest class of drug targets after G protein-coupled receptors. In addition to well-recognized ones like voltage-gated Na/K/Ca channels in the heart and neurons, novel ion channels are continuously discovered in both excitable and non-excitable cells and demonstrated to play important roles in many physiological processes and diseases such as developmental disorders, neurodegenerative diseases, and cancer. However, in the field of ion channel discovery, there are an unignorable number of published studies that are unsolid and misleading. Despite being the gold standard of a functional assay for ion channels, electrophysiological recordings are often accompanied by electrical noise, leak conductance, and background currents of the membrane system. These unwanted signals, if not treated properly, lead to the mischaracterization of proteins with seemingly unusual ion-conducting properties. In the recent ten years, the technical revolution of cryo-electron microscopy (cryo-EM) has greatly advanced our understanding of the structures and gating mechanisms of various ion channels and also raised concerns about the pore-forming ability of some previously identified channel proteins. In this review, we summarize cryo-EM findings on ion channels with molecular identities recognized or disputed in recent ten years and discuss current knowledge of proposed channel proteins awaiting cryo-EM analyses. We also present a classification of ion channels according to their architectures and evolutionary relationships and discuss the possibility and strategy of identifying more ion channels by analyzing structures of transmembrane proteins of unknown function. We propose that cross-validation by electrophysiological and structural analyses should be essentially required for determining molecular identities of novel ion channels.

Nanoarchitecture-based photothermal ablation of cancer: A systematic review.

Photothermal therapy (PTT) is an emerging non-invasive method used in cancer treatment. In PTT, near-infrared laser light is absorbed by a chromophore and converted into heat within the tumor tissue. PTT for cancer usually combines a variety of interactive plasmonic nanomaterials with laser irradiation. PTT enjoys PT agents with high conversion efficiency to convert light into heat to destroy malignant tissue. In this review, published studies concerned with the use of nanoparticles (NPs) in PTT were collected by a systematic and comprehensive search of PubMed, Cochrane, Embase, and Scopus databases. Gold, silver and iron NPs were the most frequent choice in PTT. The use of surface modified NPs allowed selective delivery and led to a precise controlled increase in the local temperature. The presence of NPs during PTT can increase the reactive generation of oxygen species, damage the DNA and mitochondria, leading to cancer cell death mainly via apoptosis. Many studies recently used core-shell metal NPs, and the effects of the polymer coating or ligands targeted to specific cellular receptors in order to increase PTT efficiency were often reported. The effective parameters (NP type, size, concentration, coated polymers or attached ligands, exposure conditions, cell line or type, and cell death mechanisms) were investigated individually. With the advances in chemical synthesis technology, NPs with different shapes, sizes, and coatings can be prepared with desirable properties, to achieve multimodal cancer treatment with precision and specificity.

Ca2+ Influx through TRPC Channels Is Regulated by Homocysteine-Copper Complexes.

An elevated level of circulating homocysteine (Hcy) has been regarded as an independent risk factor for cardiovascular disease; however, the clinical benefit of Hcy lowering-therapy is not satisfying. To explore potential unrevealed mechanisms, we investigated the roles of Ca2+ influx through TRPC channels and regulation by Hcy-copper complexes. Using primary cultured human aortic endothelial cells and HEK-293 T-REx cells with inducible TRPC gene expression, we found that Hcy increased the Ca2+ influx in vascular endothelial cells through the activation of TRPC4 and TRPC5. The activity of TRPC4 and TRPC5 was regulated by extracellular divalent copper (Cu2+) and Hcy. Hcy prevented channel activation by divalent copper, but monovalent copper (Cu+) had no effect on the TRPC channels. The glutamic acids (E542/E543) and the cysteine residue (C554) in the extracellular pore region of the TRPC4 channel mediated the effect of Hcy-copper complexes. The interaction of Hcy-copper significantly regulated endothelial proliferation, migration, and angiogenesis. Our results suggest that Hcy-copper complexes function as a new pair of endogenous regulators for TRPC channel activity. This finding gives a new understanding of the pathogenesis of hyperhomocysteinemia and may explain the unsatisfying clinical outcome of Hcy-lowering therapy and the potential benefit of copper-chelating therapy.

Functional Interrogation of Ca2+ Signals in Human Cancer Cells In Vitro and Ex Vivo by Fluorescent Microscopy and Molecular Tools.

Genetically encoded calcium indicators (GECIs) and high-resolution confocal microscopy enable dynamic visualization of calcium signals in cells and tissues. Two-dimensional and 3D biocompatible materials mimic the mechanical microenvironments of tumor and healthy tissues in a programmable manner. Cancer xenograft models and ex vivo functional imaging of tumor slices reveal physiologically relevant functions of calcium dynamics in tumors at different progression stages. Integration of these powerful techniques allows us to quantify, diagnose, model, and understand cancer pathobiology. Here, we describe detailed materials and methods used to establish this integrated interrogation platform, from generating transduced cancer cell lines that stably express CaViar (GCaMP5G + QuasAr2) to in vitro and ex vivo calcium imaging of the cells in 2D/3D hydrogels and tumor tissues. These tools open the possibility for detailed explorations of mechano-electro-chemical network dynamics in living systems.

A novel self-purified auxiliary protein enhances the lichenase activity towards lichenan for biomass degradation.

Due to the complex composition of lichenan, lichenase alone cannot always hydrolyze it efficiently. Carbohydrate-binding modules (CBMs) and lytic polysaccharide monooxygenases (LPMOs) have been confirmed to increase the hydrolysis efficiency of lichenases. However, their practical application was hampered by the complex and costly preparation procedure, as well as the poor stability of LPMOs. Herein, we discovered a novel and stable auxiliary protein named SCE to boost the hydrolysis efficiency. SCE was composed of SpyCatcher (SC) and elastin-like polypeptides (ELPs) and could be easily and cheaply prepared. Under the optimal conditions, the boosting degree for SCE/lichenase was 1.45, and the reducing sugar yield improved by nearly 45%. The results of high-performance liquid chromatography (HPLC) indicated that SCE had no influence on the hydrolysis pattern of lichenase. Through the experimental verification and bioinformatics analysis, we proposed the role of SCE in promoting the interaction between the lichenase and substrates. These findings endow SC with a novel function in binding to insoluble lichenan, paving the way for biomass degradation and biorefinery. KEY POINTS: • A novel self-purification auxiliary protein that could boost the hydrolysis efficiency of lichenase has been identified. • The protein is highly produced, simple to prepare, well stable, and does not require any external electron donor. • The novel function of SpyCatcher in binding to insoluble lichenan was first demonstrated.

Programmable and printable formaldehyde dehydrogenase as an excellent catalyst for biodegradation of formaldehyde.

As an environmental pollutant, formaldehyde can cause serious harm to the human body. Among many degradation methods, formaldehyde dehydrogenase from Pseudomonas putida (PFDH) exhibits broad potential because of its strong catalytic specificity and high degradation efficiency. However, the real application of PFDH in industry is limited by its instability and difficulties in recycling. In this work, the suitable printing conditions for immobilizing PFDH by three-dimensional (3D) printing technology were studied: the concentration of sodium alginate (SA) was 1.635 wt%, the concentration of CaCl2 was 7.4 wt%, the crosslinking time with CaCl2 was 8 min, and the temperature of the reaction was 31.5°C. 3D-printed PFDH/calcium alginate (CA) microspheres have 210% relative enzyme activity after seven repeated uses. Dried PFDH/CA particles were characterized by scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), EDS elemental mapping, and thermogravimetric analysis (TGA) which proved that the enzyme was immobilized by the material. In addition, the recycling ability of 3D printing to immobilize different objects was explored and different shapes were designed by computer-aided design (CAD). In conclusion, 3D printing technology was applied to immobilize PFDH in this work, which provides a new idea to biodegrade formaldehyde in a green way.

Forecasting China's natural gas external dependence under the "Dual Carbon" goals by a new grey model.

As a low-carbon and cost-effective clean energy source, natural gas plays an important role in achieving China's "Dual Carbon" target. In this article, a new three-parameter discrete grey prediction model is used to simulate and forecast the production and consumption of natural gas in China from the perspective of background value optimization. Then the minimum mean absolute percentage error as the objective function from the perspective of fractional order cumulative generation in the real number field. Last, a fractional order in the real number field three parameter discrete grey prediction model TDGM(1,1,z,r(R)) is constructed under the condition of optimal background value. Then we use the model to simulate and predict China's Natural Gas External Dependence (NGED) under the "Dual Carbon" target. The results show that the performance of the new model is better than that of the traditional model GM(1,1) and DGM(1,1), thus proving the practicability and effectiveness of the new model. Put forward relevant policy suggestions according to the prediction results of China's NGED, and provide decision-making reference for the Chinese government to achieve the "Dual Carbon" goals.

Revealing the role of tunable amino acid residues in elastin-like polypeptides (ELPs)-mediated biomimetic silicification.

Elastin-like polypeptides (ELPs) are attractive materials for the green preparation of silica nanoparticles via biomimetic silicification. However, the critical factors affecting the ELP-mediated silicification remain unclear. Herein, the role of tunable amino acid residues of ELPs in silicification was studied using three ELPs (ELPs[V9F-40], ELPs[KV8F-40], and ELPs[K5V4F-40]) and their fusion proteins (ELPs[V9F-40]-SpyCatcher, ELPs[KV8F-40]-SpyCatcher, and ELPs[K5V4F-40]-SpyCatcher) with different contents of lysine residues. Bioinformatics methods were employed for the first time to reveal the key physicochemical parameters correlated with silicification. The specific activity of ELPs was increased with the promotion of lysine content with a high correlation coefficient (R = 0.899). Furthermore, exogenous acidic protein SpyCatcher would hinder the interactions between the silica precursors and ELPs, leading to the significantly decrease in specific activity. The isoelectric point (pI) of ELPs presented the highest correlation to silicification with a coefficient of 0.963. The charges of the ELPs [K5V4F-40] at different pH were calculated based on the sequence or structure. Interestingly, the excellent correlation between charges based on structure and specific activity was obtained. Collectively, the novel methods developed here may pave a new way for rational design of ELPs or other peptides for efficient and green preparation of silica nanomaterials for biomedicine, biocatalysis, and biosensor.

Reply to: 'comments on 'effects of refractive accommodation on subfoveal choroidal thickness in silicone oil-filled eyes".

In this article, we answered the questions in Lei Gao et al.'s comments on the "effects of refractive accommodation on subfoveal choroidal thickness in silicone oil-filled eyes" one by one.

Human cancer cells generate spontaneous calcium transients and intercellular waves that modulate tumor growth.

Electrically excitable cells such as neurons transmit long-distance calcium or electrical signals to regulate their physiological functions. While the molecular underpinnings and down-stream effects of these intercellular communications in excitable cells have been well appreciated, little is known about whether and how non-excitable cancer cells spontaneously initiate and transmit long-distance intercellular signals. Here we report that non-excitable human colon and prostate cancer cells spontaneously initiate and spread intercellular calcium waves, in vitro and ex vivo. Xenograft model studies suggest that these calcium signals promote the growth rate of tumors in mice. Pharmacological studies elucidated that the inositol-trisphosphate-receptor (IP3R)-regulated calcium release from endoplasmic reticulum (ER), which is activated by the Gq-PLC-IP3R pathway, is a major cause for the initiation of spontaneous calcium transients. Further, the spatial-temporal characteristics of calcium dynamics can be tuned by the culture substrates of different mechanical stiffnesses. Our results provide evidence that calcium dynamics enables long-distance functional communication in non-excitable cancer cells and offer the potential to modulate calcium signaling for new cancer therapies.