Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 200
Filtrar
2.
Nat Struct Mol Biol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811792

RESUMO

Dysregulation and enhanced expression of MYC transcription factors (TFs) including MYC and MYCN contribute to the majority of human cancers. For example, MYCN is amplified up to several hundredfold in high-risk neuroblastoma. The resulting overexpression of N-myc aberrantly activates genes that are not activated at low N-myc levels and drives cell proliferation. Whether increasing N-myc levels simply mediates binding to lower-affinity binding sites in the genome or fundamentally changes the activation process remains unclear. One such activation mechanism that could become important above threshold levels of N-myc is the formation of aberrant transcriptional condensates through phase separation. Phase separation has recently been linked to transcriptional regulation, but the extent to which it contributes to gene activation remains an open question. Here we characterized the phase behavior of N-myc and showed that it can form dynamic condensates that have transcriptional hallmarks. We tested the role of phase separation in N-myc-regulated transcription by using a chemogenetic tool that allowed us to compare non-phase-separated and phase-separated conditions at equivalent N-myc levels, both of which showed a strong impact on gene expression compared to no N-myc expression. Interestingly, we discovered that only a small percentage (<3%) of N-myc-regulated genes is further modulated by phase separation but that these events include the activation of key oncogenes and the repression of tumor suppressors. Indeed, phase separation increases cell proliferation, corroborating the biological effects of the transcriptional changes. However, our results also show that >97% of N-myc-regulated genes are not affected by N-myc phase separation, demonstrating that soluble complexes of TFs with the transcriptional machinery are sufficient to activate transcription.

3.
Arch Plast Surg ; 51(1): 72-79, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38425855

RESUMO

Background Congenital muscular torticollis (CMT) is a common musculoskeletal disorder in children. Secondary scoliosis can occur in patients with CMT; however, the extent of inclination and improvement of scoliosis after surgical correction of CMT have not been adequately studied. In this study, we aimed to evaluate and measure the improvement in vertebral tilting after surgical correction according to age at the time of surgery. Methods Between June 2007 and January 2020, 831 patients with CMT underwent sternocleidomastoid release. Among them, 426 patients were enrolled, and their medical records were retrospectively reviewed. Ultimately, 210 patients available for radiological evaluation and analysis were enrolled in this study. The patients were divided into four groups according to age at the time of surgery to determine the relationship between age and changes in scoliosis. Results Our findings showed an improvement in scoliosis in all age groups after surgery. The results for follow-up after 1 year confirmed long-term improvement in vertebral tilting. The degree of improvement in scoliosis was significantly higher in the younger age group than in patients aged 18 years or older. Conclusion The effect of surgical release on scoliosis was significant in all age groups. The findings of this study suggest that CMT should be corrected before the age of 3 years to ensure an optimal surgical mitigation of scoliosis. Furthermore, in cases of neglected CMT, surgical release should be actively attempted because there is significant improvement.

4.
Nanomaterials (Basel) ; 14(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38392758

RESUMO

Lithium-sulfur batteries represent a promising class of next-generation rechargeable energy storage technologies, primarily because of their high-capacity sulfur cathode, reversible battery chemistry, low toxicity, and cost-effectiveness. However, they lack a tailored cell material and configuration for enhancing their high electrochemical utilization and stability. This study introduces a cross-disciplinary concept involving cost-efficient cement and sulfur to prepare a cement/sulfur energy storage material. Although cement has low conductivity and porosity, our findings demonstrate that its robust polysulfide adsorption capability is beneficial in the design of a cathode composite. The cathode composite attains enhanced cell fabrication parameters, featuring a high sulfur content and loading of 80 wt% and 6.4 mg cm-2, respectively. The resulting cell with the cement/sulfur cathode composite exhibits high active-material retention and utilization, resulting in a high charge storage capacity of 1189 mA∙h g-1, high rate performance across C/20 to C/3 rates, and an extended lifespan of 200 cycles. These attributes contribute to excellent cell performance values, demonstrating areal capacities ranging from 4.59 to 7.61 mA∙h cm-2, an energy density spanning 9.63 to 15.98 mW∙h cm-2, and gravimetric capacities between 573 and 951 mA∙h g-1 per electrode. Therefore, this study pioneers a new approach in lithium-sulfur battery research, opting for a nonporous material with robust polysulfide adsorption capabilities, namely cement. It effectively showcases the potential of the resulting cement/sulfur cathode composite to enhance fabrication feasibility, cell fabrication parameters, and cell performance values.

5.
Proc Natl Acad Sci U S A ; 121(7): e2310430121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315854

RESUMO

Phase separation (PS) drives the formation of biomolecular condensates that are emerging biological structures involved in diverse cellular processes. Recent studies have unveiled PS-induced formation of several transcriptional factor (TF) condensates that are transcriptionally active, but how strongly PS promotes gene activation remains unclear. Here, we show that the oncogenic TF fusion Yes-associated protein 1-Mastermind like transcriptional coactivator 2 (YAP-MAML2) undergoes PS and forms liquid-like condensates that bear the hallmarks of transcriptional activity. Furthermore, we examined the contribution of PS to YAP-MAML2-mediated gene expression by developing a chemogenetic tool that dissolves TF condensates, allowing us to compare phase-separated and non-phase-separated conditions at identical YAP-MAML2 protein levels. We found that a small fraction of YAP-MAML2-regulated genes is further affected by PS, which include the canonical YAP target genes CTGF and CYR61, and other oncogenes. On the other hand, majority of YAP-MAML2-regulated genes are not affected by PS, highlighting that transcription can be activated effectively by diffuse complexes of TFs with the transcriptional machinery. Our work opens new directions in understanding the role of PS in selective modulation of gene expression, suggesting differential roles of PS in biological processes.


Assuntos
Separação de Fases , Transcriptoma , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Oncogenes
6.
Cancer Cell ; 42(1): 1-5, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38039965

RESUMO

Recent clinical trials for H3K27-altered diffuse midline gliomas (DMGs) have shown much promise. We present a consensus roadmap and identify three major barriers: (1) refinement of experimental models to include immune and brain-specific components; (2) collaboration among researchers, clinicians, and industry to integrate patient-derived data through sharing, transparency, and regulatory considerations; and (3) streamlining clinical efforts including biopsy, CNS-drug delivery, endpoint determination, and response monitoring. We highlight the importance of comprehensive collaboration to advance the understanding, diagnostics, and therapeutics for DMGs.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Criança , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/diagnóstico , Glioma/genética , Glioma/terapia , Mutação , Encéfalo/patologia , Biópsia
7.
Mikrochim Acta ; 190(12): 489, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015281

RESUMO

Nanostructures of graphene were synthesized for electrochemical carbendazim (CBZ) fungicide detection via metal-organic chemical vapor deposition (MOCVD). The arduous process of graphene transfer is eliminated by this innovative approach to MOCVD graphene development. It also generates several defects and impurities and ultimately leads to the uniform deposition of graphene on SiO2/Si. SEM, EDX, and ICP-AES were used to assess the morphological properties and chemical composition of the materials. To obtain in-depth knowledge of the entire system, the electrochemical behavior was also investigated using voltammetric techniques and electrochemical impedance spectroscopy. The interaction of particles of copper with CBZ and the enhanced surface area of graphene, which causes a strong oxidation current, has been demonstrated to achieve the ideal CBZ sensing behavior. The electrode responded linearly at CBZ concentration levels of 1 to 50 nM, and the sensitivity of the sensing materials was estimated to be 0.0337 Ω nM-1. The statistical analysis validates the electrode's exceptional selectivity and remarkable reproducibility in determining CBZ.

8.
Cancer Discov ; 13(11): 2370-2393, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37584601

RESUMO

Patients with H3K27M-mutant diffuse midline glioma (DMG) have no proven effective therapies. ONC201 has recently demonstrated efficacy in these patients, but the mechanism behind this finding remains unknown. We assessed clinical outcomes, tumor sequencing, and tissue/cerebrospinal fluid (CSF) correlate samples from patients treated in two completed multisite clinical studies. Patients treated with ONC201 following initial radiation but prior to recurrence demonstrated a median overall survival of 21.7 months, whereas those treated after recurrence had a median overall survival of 9.3 months. Radiographic response was associated with increased expression of key tricarboxylic acid cycle-related genes in baseline tumor sequencing. ONC201 treatment increased 2-hydroxyglutarate levels in cultured H3K27M-DMG cells and patient CSF samples. This corresponded with increases in repressive H3K27me3 in vitro and in human tumors accompanied by epigenetic downregulation of cell cycle regulation and neuroglial differentiation genes. Overall, ONC201 demonstrates efficacy in H3K27M-DMG by disrupting integrated metabolic and epigenetic pathways and reversing pathognomonic H3K27me3 reduction. SIGNIFICANCE: The clinical, radiographic, and molecular analyses included in this study demonstrate the efficacy of ONC201 in H3K27M-mutant DMG and support ONC201 as the first monotherapy to improve outcomes in H3K27M-mutant DMG beyond radiation. Mechanistically, ONC201 disrupts integrated metabolic and epigenetic pathways and reverses pathognomonic H3K27me3 reduction. This article is featured in Selected Articles from This Issue, p. 2293.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Glioma/genética , Glioma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Histonas/genética , Resultado do Tratamento , Epigênese Genética , Mutação
9.
Anesth Pain Med (Seoul) ; 18(3): 252-259, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468208

RESUMO

BACKGROUND: Remimazolam is a novel benzodiazepine with fast onset and short half-life. We compared the effects of remimazolam and propofol on recovery profiles for general anesthesia in patients undergoing laparoscopic cholecystectomy. METHODS: We randomly assigned 108 patients to either a remimazolam (n=54) or propofol (n=54) group. Remimazolam and propofol were used for induction and maintanance of anesthesia. Following anesthesia, we recorded the time until an Aldrete score of 9 was achieved as the primary surrogate marker of complete recovery. The time to reach a Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score of 2 and the time from the end of anesthesia to eye opening time, recovery time of orientation, time to spontaneous breathing, extubation time, and the time required for analgesics were measured. Heart rate, blood pressure, and bispectral index were assessed before, during, and after pneumoperitoneum. RESULTS: We included 101 patients in the analysis. In the remimazolam group, it took longer to reach an Aldrete score of 9 after the drug infusion ended (P = 0.031). There was no difference in the time to reach MOAA/S 2 between the two groups. The time to eye opening, recovery time of orientation, and time required for analgesics were longer and heart rate was higher in the remimazolam group. Neither blood pressure, nor extubation time differed between groups. CONCLUSIONS: Remimazolam and propofol provided safe induction and maintenance of anesthesia in patients undergoing laparoscopic cholecystectomy. The recovery time from anesthesia was longer than that with propofol. Fewer hemodynamic changes were observed with remimazolam, but further studies are needed.

10.
Medicina (Kaunas) ; 59(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37512009

RESUMO

Background and Objectives: Postoperative nausea and vomiting (PONV) is a common adverse effect of general anesthesia, especially in middle ear surgery. Remimazolam is a newer benzodiazepine recently approved for use in general anesthesia. This study aimed to compare the incidence rate of PONV after tympanoplasty with mastoidectomy between using remimazolam and sevoflurane. Materials and Methods: This study included 80 patients undergoing elective tympanoplasty with mastoidectomy. The patients were randomly assigned to either the remimazolam or sevoflurane group. The primary outcome was the incidence rate of PONV 12 h after surgery. The secondary outcomes were the incidence rate of PONV 12-24 and 24-48 h after surgery, severity of PONV, incidence rate of vomiting, administration of rescue antiemetics, hemodynamic stability, and recovery profiles. Results: The incidence rate of PONV 0-12 h after tympanoplasty with mastoidectomy was significantly lower in the remimazolam group compared with that in the sevoflurane group (28.9 vs. 57.9%; p = 0.011). However, the incidence rate of delayed PONV did not differ between the two groups. PONV severity in the early periods after the surgery was significantly lower in the remimazolam group than in the sevoflurane group. The incidence rate of adverse hemodynamic events was lower in the remimazolam group than in the sevoflurane group, but there was no difference in the overall trends of hemodynamic data between the two groups. There was no difference in recovery profiles between the two groups. Conclusions: Remimazolam can significantly reduce the incidence rate of early PONV after tympanoplasty with mastoidectomy under general anesthesia.


Assuntos
Náusea e Vômito Pós-Operatórios , Timpanoplastia , Humanos , Náusea e Vômito Pós-Operatórios/epidemiologia , Sevoflurano/efeitos adversos , Incidência , Timpanoplastia/efeitos adversos , Mastoidectomia , Benzodiazepinas , Método Duplo-Cego
11.
Materials (Basel) ; 16(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37445017

RESUMO

An ammonia sensor based on a delay-line surface acoustic wave (SAW) device is developed in this study by coating the delay line area of the device with a nano-structured molybdenum disulfide (MoS2) sensitive material. A SAW device of 122 MHz was designed and fabricated with a pair of interdigital transducers (IDTs) defined on a 128° y-cut LiNbO3 substrate using photolithography technologies, and the aluminum IDT electrodes were deposited by a DC magnetron sputtering system. By adjusting the pH values of precursor solutions, molybdenum disulfide (MoS2) nanospheres were prepared with various structures using a hydrothermal method. Finally, an NH3 gas sensor with high sensitivity of 4878 Hz/ppm, operating at room temperature, was successfully obtained. The excellent sensitivity performance may be due to the efficient adsorption of NH3 gas molecules on the surfaces of the nanoflower-like MoS2, which has a larger specific surface area and provides more active sites, and results in a larger change in the resonant frequency of the device due to the mass loading effect.

12.
ACS Cent Sci ; 9(7): 1466-1479, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37521779

RESUMO

Biomolecular condensate is an emerging structural entity that regulates various cellular processes. Recent studies have discovered the phase-separation (PS) capability of several transcription factors (TFs) including YAP/TAZ upon biological stimuli, which provide new mechanisms of gene regulation. However, it remains mostly unanswered as to whether PS from a diffuse state to a phase-separated state promotes gene transcription. To address this question, we have designed a chemogenetic tool, dubbed SPARK-ON, which manipulates the PS of YAP and TAZ without a biological stimulus, forming condensates that are transcriptionally active, containing the DNA-binding partner TEAD, genomic DNA, transcriptional machinery, and nascent RNA. Most importantly, PS of TAZ increases the transcription of its target genes. Therefore, our data indicate that PS promotes gene transcription of TAZ. SPARK-ON is advantageous to current mutagenesis-based approaches that are often problematic when mutagenesis affects the transcriptional activity of a TF. Furthermore, protein abundance levels also affect gene transcription, but PS depends on protein abundance because PS occurs only when the protein level is above a saturation concentration. SPARK-ON decouples PS from protein abundance levels without introducing mutations and thus will find important applications in understanding the biological roles of PS for many TFs and other biomolecular condensates.

13.
Brain Tumor Res Treat ; 11(2): 86-93, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37151150

RESUMO

Diffuse midline glioma (DMG), hitherto known as diffuse intrinsic pontine glioma (DIPG), is a rare and aggressive form of brain cancer that primarily affects children. Although the exact cause of DMG/DIPG is not known, a large proportion of DMG/DIPG tumors harbor mutations in the gene encoding the histone H3 protein, specifically the H3K27M mutation. This mutation decreases the level of H3K27me3, a histone modification that plays a vital role in regulating gene expression through epigenetic regulation. The mutation also alters the function of polycomb repressive complex 2 (PRC2), thereby preventing the repression of genes associated with cancer development. The decrease in H3K27me3 caused by the histone H3 mutation is accompanied by an increase in the level of H3K27ac, a post-translational modification related to active transcription. Dysregulation of histone modification markedly affects gene expression, contributing to cancer development and progression by promoting uncontrolled cell proliferation, tumor growth, and metabolism. DMG/DIPG alters the metabolism of methionine and the tricarboxylic acid cycle, as well as glucose and glutamine uptake. The role of epigenetic and metabolic changes in the development of DMG/DIPG has been studied extensively, and understanding these changes is critical to developing therapies targeting these pathways. Studies are currently underway to identify new therapeutic targets for DMG/DIPG, which may lead to the development of effective treatments for this devastating disease.

14.
Proc Natl Acad Sci U S A ; 120(18): e2221175120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094128

RESUMO

Diffuse midline gliomas (DMGs) including diffuse intrinsic pontine gliomas (DIPGs) bearing lysine-to-methionine mutations in histone H3 at lysine 27 (H3K27M) are lethal childhood brain cancers. These tumors harbor a global reduction in the transcriptional repressive mark H3K27me3 accompanied by an increase in the transcriptional activation mark H3K27ac. We postulated that H3K27M mutations, in addition to altering H3K27 modifications, reprogram the master chromatin remodeling switch/sucrose nonfermentable (SWI/SNF) complex. The SWI/SNF complex can exist in two main forms termed BAF and PBAF that play central roles in neurodevelopment and cancer. Moreover, BAF antagonizes PRC2, the main enzyme catalyzing H3K27me3. We demonstrate that H3K27M gliomas show increased protein levels of the SWI/SNF complex ATPase subunits SMARCA4 and SMARCA2, and the PBAF component PBRM1. Additionally, knockdown of mutant H3K27M lowered SMARCA4 protein levels. The proteolysis targeting chimera (PROTAC) AU-15330 that simultaneously targets SMARCA4, SMARCA2, and PBRM1 for degradation exhibits cytotoxicity in H3.3K27M but not H3 wild-type cells. AU-15330 lowered chromatin accessibility measured by ATAC-Seq at nonpromoter regions and reduced global H3K27ac levels. Integrated analysis of gene expression, proteomics, and chromatin accessibility in AU-15330-treated cells demonstrated reduction in the levels of FOXO1, a key member of the forkhead family of transcription factors. Moreover, genetic or pharmacologic targeting of FOXO1 resulted in cell death in H3K27M cells. Overall, our results suggest that H3K27M up-regulates SMARCA4 levels and combined targeting of SWI/SNF ATPases in H3.3K27M can serve as a potent therapeutic strategy for these deadly childhood brain tumors.


Assuntos
Neoplasias Encefálicas , Glioma Pontino Intrínseco Difuso , Glioma , Humanos , Criança , Histonas/genética , Adenosina Trifosfatases/metabolismo , Lisina/genética , Cromatina , Glioma/genética , Neoplasias Encefálicas/genética , Mutação , DNA Helicases/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo
15.
Sci Adv ; 9(9): eade3760, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36857446

RESUMO

The kinase ataxia telangiectasia mutated (ATM) plays a key role in the DNA damage response (DDR). It is thus essential to visualize spatiotemporal dynamics of ATM activity during DDR. Here, we designed a robust ATM activity reporter based on phosphorylation-inducible green fluorescent protein phase separation, dubbed ATM-SPARK (separation of phases-based activity reporter of kinase). Upon ATM activation, it undergoes phase separation via multivalent interactions, forming intensely bright droplets. The reporter visualizes spatiotemporal dynamics of endogenous ATM activity in living cells, and its signal is proportional to the amount of DNA damage. ATM-SPARK also enables high-throughput screening of biological and small-molecule regulators. We identified the protein phosphatase 4 that blocks ATM activity. We also identified BGT226 as a potent ATM inhibitor with a median inhibitory concentration of ~3.8 nanomolars. Furthermore, BGT226 sensitizes cancer cells to the radiomimetic drug neocarzinostatin, suggesting that BGT226 might be combined with radiotherapeutic treatment. ATM-SPARK achieves large dynamic range, bright fluorescence, and simple signal pattern.


Assuntos
Ataxia Telangiectasia , Humanos , Proteínas de Fluorescência Verde , Dano ao DNA , Ensaios de Triagem em Larga Escala , Fosforilação , Proteínas Mutadas de Ataxia Telangiectasia
16.
Nat Microbiol ; 8(1): 121-134, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36604514

RESUMO

The coronavirus SARS-CoV-2 causes the severe disease COVID-19. SARS-CoV-2 infection is initiated by interaction of the viral spike protein and host receptor angiotensin-converting enzyme 2 (ACE2). We report an improved bright and reversible fluorogenic reporter, named SURF (split UnaG-based reversible and fluorogenic protein-protein interaction reporter), that we apply to monitor real-time interactions between spike and ACE2 in living cells. SURF has a large dynamic range with a dark-to-bright fluorescence signal that requires no exogenous cofactors. Utilizing this reporter, we carried out a high-throughput screening of small-molecule libraries. We identified three natural compounds that block replication of SARS-CoV-2 in both Vero cells and human primary nasal and bronchial epithelial cells. Cell biological and biochemical experiments validated all three compounds and showed that they block the early stages of viral infection. Two of the inhibitors, bruceine A and gamabufotalin, were also found to block replication of the Delta and Omicron variants of SARS-CoV-2. Both bruceine A and gamabufotalin exhibited potent antiviral activity in K18-hACE2 and wild-type C57BL6/J mice, as evidenced by reduced viral titres in the lung and brain, and protection from alveolar and peribronchial inflammation in the lung, thereby limiting disease progression. We propose that our fluorescent assay can be applied to identify antiviral compounds with potential as therapeutic treatment for COVID-19 and other respiratory diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Chlorocebus aethiops , Camundongos , Humanos , Animais , SARS-CoV-2/metabolismo , Células Vero , Enzima de Conversão de Angiotensina 2 , Peptidil Dipeptidase A/metabolismo , Antivirais/farmacologia
17.
Phys Chem Chem Phys ; 25(5): 4236-4242, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661277

RESUMO

Perovskite oxides are promising low-cost and stable alternative electrocatalysts for the oxygen reduction reaction (ORR), relative to the precious metal-based electrocatalysts. Despite the experimental research on substituting various transition metals into the B-site of perovskite catalysts to improve the ORR performance, the detailed ORR mechanism due to the substitution process is rarely studied. In this paper, the ORR activity of La0.5Sr0.5CoxFe1-xO3 perovskites (x = 0, 0.25, 0.5, 0.75, and 1) is studied by density functional theory (DFT). The ORR mechanism in alkaline solution is theoretically examined as a function of the Co/Fe composition at different potentials. The substitution of Co for Fe at the B-site of the perovskites dramatically changes the theoretical overpotential and enhances the activity. The HOO* formation is the potential-determining step for all the Co/Fe compositions. In comparison with the other compositions, the Co0.5/Fe0.5 composition exhibits the lowest overpotential and bonding with the reaction intermediates moderately. Furthermore, the oxygen binding energy is correlated with the bulk oxygen p-band center relative to the Fermi level. Among all the Co/Fe compositions, the Co0.5/Fe0.5 composition shows neither too low nor too high oxygen p-band center value. These results provide deep insights into the ORR mechanism on B-site substituted perovskites and guidelines for the design of cost-effective and Pt-free electrocatalysts for oxygen reduction.

18.
J Clin Med ; 13(1)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38202129

RESUMO

Lumbar plexus blocks (LPBs) are routinely employed for analgesia in hip fracture surgery; however, a novel regional technique, the pericapsular nerve group (PENG) block, potentially offers comparable pain reduction while preserving motor function. Patients aged 45-90 years who underwent hip fracture surgery were allocated to receive either a PENG block or an LPB for analgesia. The primary outcome was the incidence of quadriceps motor block (defined as the paresis or paralysis of the knee extension) at 12 h postoperatively. The secondary outcomes included the performance time, the time to first analgesic requirement, postoperative intravenous (IV) fentanyl consumption, the ability to undergo physiotherapy at 24 and 48 h, complications, sensory and motor block assessments, postoperative numeric rating scale (NRS) pain scores, and patient outcome questionnaires. There was a significantly lower incidence of quadriceps motor block at 6 h (26.7% vs. 80.0%; p < 0.001) and at 12 h (20.0% vs. 56.7%; p = 0.010). The PENG block provided better preservation of the sensory block as well as better performance time (p < 0.001) and time to first analgesia requirement (p = 0.034), whereas the LPB resulted in lower postoperative IV fentanyl consumption at 24 h (p = 0.013). The PENG block demonstrated superiority over the LPB in preserving quadriceps strength and patient satisfaction without any substantial complications, despite higher opioid consumption within the first 24 h post-surgery.

19.
Polymers (Basel) ; 14(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36559758

RESUMO

Insulated gate bipolar transistor (IGBT) is an important power device for the conversion, control, and transmission of semiconductor power, and is used in various industrial fields. The IGBT module currently uses silicone gel as an insulating layer. Since higher power density and more severe temperature applications have become the trend according to the development of electronic device industry, insulating materials with improved heat resistance and insulation performances should be developed. In this study, we intended to synthesize a new insulating material with enhanced thermal stability and reduced thermal conductivity. Poly(imide-siloxane) (PIS) was prepared and crosslinked through a hydrosilylation reaction to obtain a semi-solid Crosslinked PIS. Thermal decomposition temperature, thermal conductivity, optical transparency, dielectric constant, and rheological property of the Crosslinked PIS were investigated and compared to those of a commercial silicone gel. The Crosslinked PIS showed high thermal stability and low thermal conductivity, along with other desirable properties, and so could be useful as an IGBT-insulating material.

20.
Pain Res Manag ; 2022: 6022380, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569462

RESUMO

The pericapsular nerve group (PENG) block targets the nerves innervating the anterior hip surface; however, few studies on this technique are currently available. We investigated the effects of the PENG block on postoperative opioid consumption after a hip surgery. This was a randomized, double-blind, placebo-controlled study conducted at a single institution. Fifty patients undergoing hip surgery were randomly allocated, 25 in each group, to receive a PENG block either using 25 mL of 0.5% ropivacaine (PENG group) or 25 mL of saline (control group). The primary outcome was the total opioid consumption 24 h postoperatively. The secondary outcomes were postoperative pain scores, time to first opioid demand, sensory block efficiency, quadriceps muscle strength, complications, and patient satisfaction. Compared with those in the control group, patients in the PENG group had a significantly lower total opioid consumption 24 h postoperatively (440.72 ± 242.20 µg vs. 611.07 ± 313.89 µg, P = 0.037) and significantly lower pain scores at 30 min postblock and 6 postoperatively (P < 0.001 and P < 0.001, respectively). The time to first opioid demand was significantly shorter in the control group than in the PENG group (P < 0.001). Sensory block effectiveness was better in the PENG group 30 min postblock and 6 and 12 h postoperatively than in the control group. Patient satisfaction was also better in the PENG group than in the control group. There were no differences in the other outcomes. The PENG block reduced the total opioid consumption in the first 24 h after hip surgery with no significant effects on quadriceps muscle strength and complication rate. This study was registered at the Korea Clinical Research Information Service (cris.nih.go.kr; Reg. No. KCT0006348) on July 16, 2021.


Assuntos
Analgésicos Opioides , Bloqueio Nervoso , Humanos , Analgésicos Opioides/uso terapêutico , Nervo Femoral , Bloqueio Nervoso/métodos , Ropivacaina , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Método Duplo-Cego
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA