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BACKGROUND: Laccase (LAC) gene family plays a pivotal role in plant lignin biosynthesis and adaptation to various stresses. Limited research has been conducted on laccase genes in common beans. RESULTS: 29 LAC gene family members were identified within the common bean genome, distributed unevenly in 9 chromosomes. These members were divided into 6 distinct subclades by phylogenetic analysis. Further phylogenetic analyses and synteny analyses indicated that considerable gene duplication and loss presented throughout the evolution of the laccase gene family. Purified selection was shown to be the major evolutionary force through Ka / Ks. Transcriptional changes of PvLAC genes under low temperature and salt stress were observed, emphasizing the regulatory function of these genes in such conditions. Regulation by abscisic acid and gibberellins appears to be the case for PvLAC3, PvLAC4, PvLAC7, PvLAC13, PvLAC14, PvLAC18, PvLAC23, and PvLAC26, as indicated by hormone induction experiments. Additionally, the regulation of PvLAC3, PvLAC4, PvLAC7, and PvLAC14 in response to nicosulfuron and low-temperature stress were identified by virus-induced gene silence, which demonstrated inhibition on growth and development in common beans. CONCLUSIONS: The research provides valuable genetic resources for improving the resistance of common beans to abiotic stresses and enhance the understanding of the functional roles of the LAC gene family.
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Lacasa , Familia de Multigenes , Phaseolus , Filogenia , Estrés Fisiológico , Phaseolus/genética , Phaseolus/enzimología , Phaseolus/fisiología , Lacasa/genética , Lacasa/metabolismo , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Regulación de la Expresión Génica de las Plantas , Genes de PlantasRESUMEN
Sulfuration reactions dominate the synthesis of transition-metal dichalcogenides via chemical vapor deposition. A neglected critical issue is the evolution of crystal domain morphology and growth models caused by boundary layer development. In this study, we propose two growth models within a laminar flow field to investigate the kinetic mechanism of uniformly grown MoS2. We used supercritical fluid pre-deposition to obtain a well-distributed and low-crystallinity Mo precursor on the surface of a substrate to avoid non-stoichiometric supply in sulfuration. The development of the boundary layer was suppressed through mainstream force by adjusting the substrate slope angle. For growth within the underdeveloped laminar boundary layer, monolayer MoS2 with a size of 50 µm uniformly distributed on the full substrate with R = 85% (relative change in boundary layer thickness). Moreover, the growth constrained by surface chemical reactions tended to promote spatially uniform growth. However, within the fully developed laminar flow, the crystal domains preferentially grew vertically, which was attributed to the excessive crystal growth rate (g). Our results provide new insights into the controllable preparation of two-dimensional materials.
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The poor prognosis observed in elderly individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a serious clinical burden and the underlying mechanism is unclear, which necessities detailed investigation of disease characteristics and research for efficient countermeasures. To simulate lethal coronavirus disease 2019 (COVID-19) in senescent human patients, 80-week-old male hamsters are intranasally inoculated with different doses of SARS-CoV-2 Omicron BA.5 variant. Exposure to a low dose of the Omicron BA.5 variant results in early activation of the innate immune response, followed by rapid viral clearance and minimal lung damage. However, a high dose of BA.5 results in impaired interferon signaling, cytokine storm, uncontrolled viral replication, and severe lung injury. To decrease viral load and reverse the deterioration of COVID-19, a new bio-mimic decoy called CoVR-MV is used as a preventive or therapeutic agent. Administration of CoVR-MV as a preventive or therapeutic intervention in the early stages of infection can effectively suppress viral load, regulate the immune response, and rescue animals from death and critical illness. These findings underscore the risk associated with SARS-CoV-2 Omicron BA.5 exposure in senescent hamsters and highlight the importance of early intervention to prevent disease progression.
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W-band (75-110 GHz) is a potential radio frequency band to provide long-distance wireless links for mobile data transmission. This paper proposes and experimentally demonstrates high-speed wireless transmission at W-band using photonics-aided method, including optical heterodyne, photonics-aided down-conversion without RF oscillator and coherent detection. A comparison between the photonics-aided method and the conventional electronic method employing solid-state electronic devices is conducted for the first time. The photonics-aided method is shown to offer advantages such as lower harmonic components, spur, reduced nonlinearity, and no local oscillator leakage, results in a 2.5 dB better performance of the photonic-aided W-band mm-wave transmitter compared to the electronic one. In the terms of receiver, the photonics-aided method can surpass the electronic method, with the help of larger electro-optical modulator bandwidth and lower drive voltage in the photonic down-conversion stage. Ultimately, using the photonics-aided method, a recorded equivalent transmission distance of 29 km@84 GHz and 45km@75.6GHz is achieved respectively for 1Gbaud QPSK signal.
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Smc5/6 is a member of the eukaryotic structural maintenance of chromosomes (SMC) family of complexes with important roles in genome maintenance and viral restriction. However, limited structural understanding of Smc5/6 hinders the elucidation of its diverse functions. Here, we report cryo-EM structures of the budding yeast Smc5/6 complex in eight-subunit, six-subunit and five-subunit states. Structural maps throughout the entire length of these complexes reveal modularity and key elements in complex assembly. We show that the non-SMC element (Nse)2 subunit supports the overall shape of the complex and uses a wedge motif to aid the stability and function of the complex. The Nse6 subunit features a flexible hook region for attachment to the Smc5 and Smc6 arm regions, contributing to the DNA repair roles of the complex. Our results also suggest a structural basis for the opposite effects of the Nse1-3-4 and Nse5-6 subcomplexes in regulating Smc5/6 ATPase activity. Collectively, our integrated structural and functional data provide a framework for understanding Smc5/6 assembly and function.
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Bacillus spp. has been considered a promising source for identifying new antimicrobial substances, including anti-viral candidates. Here, we successfully isolated a number of bacteria strains from aged dry citrus peel (Chenpi). Of note, the culture supernatant of a new isolate named Bacillus subtilis LjM2 demonstrated strong inhibition of influenza A virus (IAV) infection in multiple experimental systems in vitro and in vivo. In addition, the anti-viral effect of LjM2 was attributed to its direct lysis of viral particles. Further analysis showed that a protease which we named CPAVM1 isolated from the culture supernatant of LjM2 was the key component responsible for its anti-viral function. Importantly, the therapeutic effect of CPAVM1 was still significant when applied 12 hours after IAV infection of experimental mice. Moreover, we found that the CPAVM1 protease cleaved multiple IAV proteins via targeting basic amino acid Arg or Lys. Furthermore, this study reveals the molecular structure and catalytic mechanism of CPAVM1 protease. During catalysis, Tyr75, Tyr77, and Tyr102 are important active sites. Therefore, the present work identified a special protease CPAVM1 secreted by a new strain of Bacillus subtilis LjM2 against influenza A virus infection via direct cleavage of critical viral proteins, thus facilitates future biotechnological applications of Bacillus subtilis LjM2 and the protease CPAVM1.
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Antivirales , Bacillus subtilis , Infecciones por Orthomyxoviridae , Animales , Ratones , Antivirales/farmacología , Infecciones por Orthomyxoviridae/virología , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza A/enzimología , Péptido Hidrolasas/metabolismo , Perros , Ratones Endogámicos BALB C , Humanos , Proteínas Virales/metabolismo , Proteínas Virales/genética , Células de Riñón Canino Madin Darby , Femenino , Proteínas Bacterianas/metabolismoRESUMEN
Objective: Gastric cancer (GC) is the world's third-leading cause of cancer-related mortality; the prognosis for GC patients remains poor in terms of a lack of reliable biomarkers for early diagnosis and immune therapy response prediction. Here, we aim to discover the connection between chemokine ligand 14 (CCL14) expression in the gastric tumor microenvironment (TME) and its clinical significance and investigate its correlation with immune cell infiltration. Methods: We assessed CCL14 mRNA expression and its interrelation with tumor-infiltrating immune cells (TILs) using bioinformatics analysis in gastric cancer. CCL14 protein expression, TILs, and immune checkpoints were detected by multiple immunohistochemistry analyses in gastric cancer tissue microarrays. Then, we conducted statistics analysis to determine the association between CCL14-related patient survival and immune cell infiltration (p < 0.05). Results: We found that the CCL14 protein was separately expressed in the carcinoma cells and TILs in stomach cancer tissues. The CCL14 protein was related to tumor differentiation and tumor depth and positively correlated with the presentation of LAG3 and PD-L1 in gastric cancer cells. In addition, the CCL14 protein in the TILs of gastric cancer tissues was related to Lauren's type cells, T cells (CD4+ and CD8+), and CD68+ macrophages in the TME. Kaplan-Meier survival and multivariate analyses showed that the CCL14 expression in gastric cancer cells was an independent prognostic factor. Conclusion: Our study illustrated that CCL14 is a poor prognosis biomarker in gastric cancer, which may be associated with the potential for immunotherapy.
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Arbuscular mycorrhizal (AM) fungi can enhance the uptake of soil nutrients and water by citrus, promoting its growth. However, the specific mechanisms underlying the action of AM fungi in promoting the growth of citrus were not fully elucidated. This study aimed to explore the role of AM fungi Funneliformis mosseae in the regulatory mechanisms of P. trifoliata growth. Pot experiments combined with non-targeted metabolomics methods were used to observe the growth process and changes in metabolic products of P. trifoliata under the conditions of F. mosseae inoculation. The results showed that F. mosseae could form an excellent symbiotic relationship with P. trifoliata, thereby enhancing the utilization of soil nutrients and significantly promoting its growth. Compared with the control, the plant height, stem diameter, number of leaves, and aboveground and underground dry weight in the F. mosseae inoculation significantly increased by 2.57, 1.29, 1.57, 4.25, and 2.78 times, respectively. Moreover, the root system results confirmed that F. mosseae could substantially promote the growth of P. trifoliata. Meanwhile, the metabolomics data indicated that 361 differential metabolites and 56 metabolic pathways were identified in the roots of P. trifoliata and were inoculated with F. mosseae. This study revealed that the inoculated F. mosseae could participate in ABC transporters by upregulating their participation, glycerophospholipid metabolism, aminoacyl tRNA biosynthesis, tryptophan metabolism and metabolites from five metabolic pathways of benzoxazinoid biosynthesis [mainly enriched in lipid (39.50%) and amino acid-related metabolic pathways] to promote the growth of P. trifoliata.
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Selective separation of ethylene and ethane (C2H4/C2H6) is a formidable challenge due to their close molecular size and boiling point. Compared to industry-used cryogenic distillation, adsorption separation would offer a more energy-efficient solution when an efficient adsorbent is available. Herein, a class of C2H4/C2H6 separation adsorbents, doped carbon molecular sieves (d-CMSs) is reported which are prepared from the polymerization and subsequent carbonization of resorcinol, m-phenylenediamine, and formaldehyde in ethanol solution. The study demonstrated that the polymer precursor themselves can be a versatile platform for modifying the pore structure and surface functional groups of their derived d-CMSs. The high proportion of pores centered at 3.5 Å in d-CMSs contributes significantly to achieving a superior kinetic selectivity of 205 for C2H4/C2H6 separation. The generated pyrrolic-N and pyridinic-N functional sites in d-CMSs contribute to a remarkable elevation of Henry selectivity to 135 due to the enhancement of the surface polarity in d-CMSs. By balancing the synergistic effects of kinetics and thermodynamics, d-CMSs achieve efficient separation of C2H4/C2H6. Polymer-grade C2H4 of 99.71% purity can be achieved with 75% recovery using the devised d-CMSs as reflected in a two-bed vacuum swing adsorption simulation.
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Exercise training effectively relieves anxiety disorders via modulating specific brain networks. The role of post-translational modification of proteins in this process, however, has been underappreciated. Here we performed a mouse study in which chronic restraint stress-induced anxiety-like behaviors can be attenuated by 14-day persistent treadmill exercise, in association with dramatic changes of protein phosphorylation patterns in the medial prefrontal cortex (mPFC). In particular, exercise was proposed to modulate the phosphorylation of Nogo-A protein, which drives the ras homolog family member A (RhoA)/ Rho-associated coiled-coil-containing protein kinases 1(ROCK1) signaling cascade. Further mechanistic studies found that liver-derived kynurenic acid (KYNA) can affect the kynurenine metabolism within the mPFC, to modulate this RhoA/ROCK1 pathway for conferring stress resilience. In sum, we proposed that circulating KYNA might mediate stress-induced anxiety-like behaviors via protein phosphorylation modification within the mPFC, and these findings shed more insights for the liver-brain communications in responding to both stress and physical exercise.
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Antitumor therapies based on adoptively transferred T cells or oncolytic viruses have made significant progress in recent years, but the limited efficiency of their infiltration into solid tumors makes it difficult to achieve desired antitumor effects when used alone. In this study, an oncolytic virus (rVSV-LCMVG) that is not prone to induce virus-neutralizing antibodies was designed and combined with adoptively transferred T cells. By transforming the immunosuppressive tumor microenvironment into an immunosensitive one, in B16 tumor-bearing mice, combination therapy showed superior antitumor effects than monotherapy. This occurred whether the OV was administered intratumorally or intravenously. Combination therapy significantly increased cytokine and chemokine levels within tumors and recruited CD8+ T cells to the TME to trigger antitumor immune responses. Pretreatment with adoptively transferred T cells and subsequent oncolytic virotherapy sensitizes refractory tumors by boosting T-cell recruitment, down-regulating the expression of PD-1, and restoring effector T-cell function. To offer a combination therapy with greater translational value, mRNA vaccines were introduced to induce tumor-specific T cells instead of adoptively transferred T cells. The combination of OVs and mRNA vaccine also displays a significant reduction in tumor burden and prolonged survival. This study proposed a rational combination therapy of OVs with adoptive T-cell transfer or mRNA vaccines encoding tumor-associated antigens, in terms of synergistic efficacy and mechanism.
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Viroterapia Oncolítica , Virus Oncolíticos , Animales , Ratones , Virus Oncolíticos/genética , Virus Oncolíticos/inmunología , Viroterapia Oncolítica/métodos , Terapia Combinada , Vacunas de ARNm/inmunología , Melanoma Experimental/terapia , Melanoma Experimental/inmunología , Microambiente Tumoral/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T/inmunología , Humanos , Línea Celular Tumoral , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/genética , Vacunas contra el Cáncer/administración & dosificaciónRESUMEN
BACKGROUND: The Oka varicella vaccine strain remains neurovirulent and can establish lifelong latent infection, raising safety concerns about vaccine-related herpes zoster. In this study, we aimed to evaluate the immunogenicity and safety of a skin-attenuated and neuro-attenuated varicella vaccine candidate (v7D vaccine). METHODS: We did this randomised, double-blind, controlled, phase 2a clinical trial in Jiangsu, China. Healthy children aged 3-12 years with no history of varicella infection or vaccination were enrolled and randomly assigned (1:1:1:1) to receive a single subcutaneous injection of the v7D vaccine at 3·3 log10 plaque forming units (PFU; low-dose v7D group), 3·9 log10 PFU (medium-dose v7D group), and 4·2 log10 PFU (high-dose v7D group), or the positive control varicella vaccine (vOka vaccine group). All the participants, laboratory personnel, and investigators other than the vaccine preparation and management staff were masked to the vaccine allocation. The primary outcome was assessment of the geometric mean titres (GMTs) and seroconversion rates of anti-varicella zoster virus immunoglobulin G (IgG) induced by different dose groups of v7D vaccine at 0, 42, 60, and 90 days after vaccination in the per-protocol set for humoral immune response analysis. Safety was a secondary outcome, focusing on adverse events within 42 days post-vaccination, and serious adverse events within 6 months after vaccination. This study was registered on Chinese Clinical Trial Registry, ChiCTR2000034434. FINDINGS: On Aug 18-21, 2020, 842 eligible volunteers were enrolled and randomly assigned treatment. After three participants withdrew, 839 received a low dose (n=211), middle dose (n=210), or high dose (n=210) of v7D vaccine, or the vOka vaccine (n=208). In the per-protocol set for humoral immune response analysis, the anti-varicella zoster virus IgG antibody response was highest at day 90. At day 90, the seroconversion rates of the low-dose, medium-dose, and high-dose groups of v7D vaccine and the positive control vOka vaccine group were 100·0% (95% CI 95·8-100·0; 87 of 87 participants), 98·9% (93·8-100·0; 87 of 88 participants), 97·8% (92·4-99·7; 91 of 93 participants), and 96·4% (89·8-99·2; 80 of 83 participants), respectively; the GMTs corresponded to values of 30·8 (95% CI 26·2-36·0), 31·3 (26·7-36·6), 28·2 (23·9-33·2), and 38·5 (31·7-46·7). The v7D vaccine, at low dose and medium dose, elicited a humoral immune response similar to that of the vOka vaccine. However, the high-dose v7D vaccine induced a marginally lower GMT compared with the vOka vaccine at day 90 (p=0·027). In the per-protocol set, the three dose groups of the v7D vaccine induced a similar humoral immune response at each timepoint, with no statistically significant differences. The incidence of adverse reactions in the low-dose, medium-dose, and high-dose groups of v7D vaccine was significantly lower than that in the vOka vaccine group (17% [35 of 211 participants], 20% [41 of 210 participants], and 13% [27 of 210 participants] vs 24% [50 of 208 participants], respectively; p=0·025), especially local adverse reactions (10% [22 of 211 participants], 14% [30 of 210 participants] and 9% [18 of 210 participants] vs 18% [38 of 208 participants], respectively; p=0·016). None of the serious adverse events were vaccine related. INTERPRETATION: The three dose groups of the candidate v7D vaccine exhibit similar humoral immunogenicity to the vOka vaccine and are well tolerated. These findings encourage further investigations on two-dose vaccination schedules, efficacy, and the potential safety benefit of v7D vaccine in the future. FUNDING: The National Natural Science Foundation of China, CAMS Innovation Fund for Medical Sciences, the Fundamental Research Funds for the Central Universities, and Beijing Wantai. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.
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Anticuerpos Antivirales , Vacuna contra la Varicela , Varicela , Vacunas Atenuadas , Humanos , Vacuna contra la Varicela/inmunología , Vacuna contra la Varicela/administración & dosificación , Vacuna contra la Varicela/efectos adversos , Método Doble Ciego , Vacunas Atenuadas/inmunología , Vacunas Atenuadas/administración & dosificación , Vacunas Atenuadas/efectos adversos , Masculino , Femenino , Preescolar , Niño , Anticuerpos Antivirales/sangre , Varicela/prevención & control , Varicela/inmunología , China , Herpesvirus Humano 3/inmunología , Inmunogenicidad Vacunal , Vacunación/métodosRESUMEN
Two-dimensional (2D) alloys hold great promise to serve as important components of 2D transistors, since their properties allow continuous regulation by varying their compositions. However, previous studies are mainly limited to the metallic/semiconducting ones as contact/channel materials, but very few are related to the insulating dielectrics. Here, we use a facile one-step chemical vapor deposition (CVD) method to synthesize ultrathin Bi2SixGe1-xO5 dielectric alloys, whose composition is tunable over the full range of x just by changing the relative ratios of the GeO2/SiO2 precursors. Moreover, their dielectric properties are highly composition-tunable, showing a record-high dielectric constant of >40 among CVD-grown 2D insulators. The vertically grown nature of Bi2GeO5 and Bi2SixGe1-xO5 enables polymer-free transfer and subsequent clean van der Waals integration as the high-κ encapsulation layer to enhance the mobility of 2D semiconductors. Besides, the MoS2 transistors using Bi2SixGe1-xO5 alloy as gate dielectrics exhibit a large Ion/Ioff (>108), ideal subthreshold swing of â¼61 mV/decade, and a small gate hysteresis (â¼5 mV). Our work not only gives very few examples on controlled CVD growth of insulating dielectric alloys but also expands the family of 2D single-crystalline high-κ dielectrics.
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Rhinoviruses (RVs) are major causes of the common cold and are related to severe respiratory tract diseases, leading to a considerable economic burden and impacts on public health. Available and stable viral resources of rhinoviruses for laboratory use are important for promoting studies on rhinoviruses and further vaccine or therapeutic drug development. Reverse genetic technology can be useful to produce rhinoviruses and will help to promote studies on their pathogenesis and virulence. In this study, rhinovirus A89, an RV-A species that has been found to be highly involved in hospitalization triggered by RV infections, was selected to construct an infectious clone based on its sequence as a representative. The viral mRNA produced by a T7 RNA transcript system was transfected into H1-HeLa cells, and the rescued RV-A89 viruses were harvested and confirmed by sequencing. The rescued RV-A89 induced a similar cytopathic effect (CPE) and shared almost identical growth kinetics curves with parental RV-A89. Moreover, 9A7, a prescreened monoclonal antibody against the parental RV-A89, had a good and specific reaction with the rescued RV-A89, and further characterization showed almost the same morphology and protein composition of both viruses; thus, recombinant RV-A89 with similar biological characterization and virulence to the parental virus was obtained. In summary, the infectious clone of RV-A89 was successfully established, and the development of reverse genetic technology for rhinovirus will provide a framework for further studies on rhinoviruses.
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Circular RNAs (circRNAs) represent a novel class of non-coding RNAs that play significant roles in tumorigenesis and tumor progression. High-throughput sequencing of gastric cancer (GC) tissues has identified circRNA BIRC6 (circBIRC6) as a potential circRNA derived from the BIRC6 gene, exhibiting significant upregulation in GC tissues. The expression of circBIRC6 is notably elevated in GC patients. Functionally, it acts as a molecular sponge for miR-488, consequently upregulating GRIN2D expression and promoting GC proliferation, migration, and invasion. Moreover, overexpression of circBIRC6 leads to increased GRIN2D expression, which in turn enhances caveolin-1 (CAV1) expression, resulting in autophagy deficiency due to miR-488 sequestration. This cascade of events significantly influences tumorigenesis in vivo. Our findings collectively illustrate that the CircBIRC6-miR-488-GRIN2D axis fosters CAV1 expression in GC cells, thereby reducing autophagy levels. Both circBIRC6 and GRIN2D emerge as potential targets for treatment and independent prognostic factors for GC patients.
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MicroARNs , Neoplasias Gástricas , Humanos , Autofagia , Caveolina 1/genética , Caveolina 1/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Transformación Celular Neoplásica , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , MicroARNs/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Neoplasias Gástricas/patologíaRESUMEN
Background/purpose: Optimal sedation management for pediatric dental treatment demands special focus as it's tubeless and shares a same oral space. The study was to evaluate dexmedetomidine compared to midazolam for intranasal premedication in pediatric dental treatment under intravenous deep sedation. Materials and methods: A hundred children aged 3-7 years scheduled for elective dental treatment under intravenous deep sedation anesthesia were enrolled, of whom 50 children (Group D) were intranasally premedicated with 2.0 µg/kg dexmedetomidine and the remaining 50 children (Group M) received traditional 0.2 mg/kg midazolam. Acceptance rate of venipuncture was regarded as the primary endpoint. Results: The acceptance rate of venipuncture in Group D and Group M were 76% versus 52%, respectively (P = 0.021). More children in Group M complained about bitter/sour taste than Group D (62% vs. 8%, P < 0.001). Intraoperatively, children in Group M were found to have more choking cough than Group D (30% vs. 9%, P = 0.003), and patients in Group M required more suction (18 [36%] in Group M vs. 4 [8%] in Group D, P = 0.001). There were no significant differences between the groups in the incidences of temporal hypoxemia (SpO2 ≤ 90%), however, two children in Group M experienced hypoxemia over 10 s. Conclusion: Compared to the 0.2 mg/kg midazolam, children premedicated with 2.0 µg/kg intranasal dexmedetomidine showed superior venipuncture acceptance, had less intraoperative choking cough and required fewer suction. It seems to be a good alternative to midazolam as premedication for deep sedation in pediatric dental treatment.
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Uremic toxins play a crucial role in the development of low bone turnover disease in chronic kidney disease (CKD) through the induction of oxidative stress. This oxidative stress disrupts the delicate balance between bone formation and resorption, resulting in a decline in both bone quantity and quality. Reactive oxygen species (ROS) activate nuclear factor kappa-B and mitogen-activated protein kinase signaling pathways, promoting osteoclastogenesis. Conversely, ROS hinder osteoblast differentiation by facilitating the binding of Forkhead box O proteins (FoxOs) to ß-catenin, triggering apoptosis through FoxOs-activating kinase phosphorylation. This results in increased osteoblastic receptor activator of nuclear factor kappa-B ligand (RANKL) expression and decreased nuclear factor erythroid 2-related factor 2 levels, compromising antioxidant defenses against oxidative damage. As CKD progresses, the accumulation of protein-bound uremic toxins such as indoxyl sulfate (IS) and p-cresyl sulfate (PCS) intensifies oxidative stress, primarily affecting osteoblasts. IS and PCS directly inhibit osteoblast viability, induce apoptosis, decrease alkaline phosphatase activity, and impair collagen 1 and osteonectin, impeding bone formation. They also reduce cyclic adenosine 3',5'-monophosphate (cAMP) production and lower parathyroid hormone (PTH) receptor expression in osteoblasts, resulting in PTH hyporesponsiveness. In summary, excessive production of ROS by uremic toxins not only reduces the number and function of osteoblasts but also induces PTH hyporesponsiveness, contributing to the initiation and progression of low bone turnover disease in CKD.
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Cells sense physical forces and convert them into electrical or chemical signals, a process known as mechanotransduction. Whereas extensive studies focus on mechanotransduction at the plasma membrane, little is known about whether and how intracellular organelles sense mechanical force and the physiological functions of organellar mechanosensing. Here we identify the Drosophila TMEM63 (DmTMEM63) ion channel as an intrinsic mechanosensor of the lysosome, a major degradative organelle. Endogenous DmTMEM63 proteins localize to lysosomes, mediate lysosomal mechanosensitivity and modulate lysosomal morphology and function. Tmem63 mutant flies exhibit impaired lysosomal degradation, synaptic loss, progressive motor deficits and early death, with some of these mutant phenotypes recapitulating symptoms of TMEM63-associated human diseases. Importantly, mouse TMEM63A mediates lysosomal mechanosensitivity in Neuro-2a cells, indicative of functional conservation in mammals. Our findings reveal DmTMEM63 channel function in lysosomes and its physiological roles in vivo and provide a molecular basis to explore the mechanosensitive process in subcellular organelles.