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The neuromuscular junction (NMJ) is an interface between motor neurons and skeletal muscle fibers, facilitating the transmission of signals that initiate muscle contraction. Its pivotal role lies in ensuring efficient communication between the nervous system and muscles, allowing for precise and coordinated movements essential for everyday activities and overall motor function. To provide insights into neuromuscular disease and development, understanding the physiology of NMJ is essential. We target acetylcholine receptors (AChR) by immunofluorescence assay (IFA) with α-bungarotoxin (BTX; snake venom neurotoxins binding to AChR) to visualize and quantify the NMJ. Changes in AChR distribution or structure can indicate alterations in receptor density, which may be associated with neuromuscular disorders or conditions that affect synaptic transmission. This protocol provides the methodology for isolating and longitudinally sectioning gastrocnemius muscle for AChR-targeted IFA for confocal microscopy and performing quantitative analysis of NMJs. Key features ⢠Visualizes and quantifies NMJs using α-bungarotoxin. ⢠Utilizes high-resolution confocal microscopy for detailed imaging.
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Outbreaks of short beak and dwarfism syndrome (SBDS), caused by a novel goose parvovirus (NGPV), have occurred in China since 2015. The NGPV, a single-stranded DNA virus, is thought to be vertically transmitted. However, the mechanism of NGPV immune evasion remains unclear. In this study, we investigated the impact of NGPV infection on the Cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in duck embryonic fibroblast (DEF) cells. Our findings demonstrate that NGPV infection stimulates the mRNA expression of cGAS but results in weak IFN-ß induction. NGPV impedes the expression of IFN-ß and downstream interferon-stimulated genes, thereby reducing the secretion of IFN-ß induced by interferon-stimulating DNA (ISD) and poly (I: C). RNA-seq results show that NGPV infection downregulates interferon mRNA expression while enhancing the mRNA expression of inflammatory factors. Additionally, the results of viral protein over-expression indicate that VP1 exhibits a remarkable ability to inhibit IFN-ß expression compared to other viral proteins. Results indicated that only the intact VP1 protein could inhibit the expression of IFN-ß, while the truncated proteins VP1U and VP2 do not possess such characteristics. The immunoprecipitation experiment showed that both VP1 and VP2 could interact with IRF7 protein, while VP1U does not. In summary, our findings indicate that NGPV infection impairs the host's innate immune response by potentially modulating the expression and secretion of interferons and interferon-stimulating factors via IRF7 molecules, which are regulated by the VP1 protein.
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Factor 7 Regulador del Interferón , Infecciones por Parvoviridae , Parvovirinae , Enfermedades de las Aves de Corral , Transducción de Señal , Animales , Enfermedades de las Aves de Corral/virología , Enfermedades de las Aves de Corral/inmunología , Infecciones por Parvoviridae/veterinaria , Infecciones por Parvoviridae/virología , Infecciones por Parvoviridae/inmunología , Factor 7 Regulador del Interferón/metabolismo , Factor 7 Regulador del Interferón/genética , Parvovirinae/genética , Parvovirinae/fisiología , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Patos , Gansos , Interferón Tipo I/metabolismo , Interferón Tipo I/genética , Interferón Tipo I/inmunologíaRESUMEN
Thymic egress is a crucial process for thymocyte maturation, strictly regulated by sphingosine-1-phosphate lyase (S1PL). Recently, cystathionine γ-lyase (CSE), one of the enzymes producing hydrogen sulfide (H2S), has emerged as a vital immune process regulator. However, the molecular connection between CSE, H2S and thymic egress remains largely unexplored. In this study, we investigated the regulatory function of CSE in the thymic egress of immune cells. We showed that genetic knockout of CSE or pharmacological inhibition by CSE enzyme inhibitor NSC4056 or D,L-propargylglycine (PAG) significantly enhanced the migration of mature lymphocytes and monocytes from the thymus to the peripheral blood, and this redistribution effect could be reversed by treatment with NaHS, an exogenous donor of H2S. In addition, the CSE-generated H2S significantly increased the levels of S1P in the peripheral blood, thymus and spleen of mice, suppressed the production of proinflammatory cytokines and rescued pathogen-induced sepsis in cells and in vivo. Notably, H2S or polysulfide inhibited S1PL activity in cells and an in vitro purified enzyme assay. We found that this inhibition relied on a newly identified C203XC205 redox motif adjacent to the enzyme's active site, shedding light on the biochemical mechanism of S1PL regulation. In conclusion, this study uncovers a new function and mechanism for CSE-derived H2S in thymic egress and provides a potential drug target for treating S1P-related immune diseases.
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Aldehído-Liasas , Cistationina gamma-Liasa , Sulfuro de Hidrógeno , Ratones Endogámicos C57BL , Timo , Cistationina gamma-Liasa/metabolismo , Cistationina gamma-Liasa/antagonistas & inhibidores , Sulfuro de Hidrógeno/metabolismo , Animales , Aldehído-Liasas/metabolismo , Aldehído-Liasas/antagonistas & inhibidores , Timo/metabolismo , Timo/efectos de los fármacos , Regulación Alostérica/efectos de los fármacos , Ratones , Alquinos/farmacología , Ratones Noqueados , Glicina/análogos & derivados , Glicina/farmacología , Glicina/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Masculino , Movimiento Celular/efectos de los fármacosRESUMEN
BACKGROUND: As limited antibiotic options are available for the treatment of carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infections (BSIs), the optimal treatment duration for CRKP BSIs is unclear. Our objective was to investigate whether short courses (6-10 days) are as effective as prolonged courses (≥11 days) of active antibiotic therapy for CRKP BSIs. METHODS: A retrospective cohort study comprising adults with monomicrobial CRKP BSI receiving a short or prolonged course of in vitro active therapy at a medical center was conducted between 2010 and 2021. Comparisons of two therapeutic strategies were assessed by the logistic regression model and propensity score analysis. The primary endpoint was 30-day crude mortality. Secondary outcomes included recurrent BSIs, the emergence of multidrug-resistant organisms and candidemia during hospitalization after completing antibiotic therapy for CRKP BSIs. RESULTS: Of 263 eligible adults, 160 (60.8%) were male, and the median (interquartile range) age was 69.0 (53.0-76.0) years. Common comorbidities included diabetes (143 patients, 54.4%), malignancy (75, 28.5%), cerebrovascular accident (58, 22.1%), and hemodialysis (49, 18.6%). The 30-day mortality rate was 8.4% (22 patients). Of 84 propensity score well-balanced matched pairs, the 30-day mortality was similar in the short-course and prolonged-course group (6.0% and 7.1%, respectively; P = 1.00). However, there were less episodes candidemia in the short-course group (1.2% versus 13.1%; odds ratio, 0.08; 95% confidence interval, 0.01-0.63; P = 0.005). CONCLUSION: Short courses of active therapy for CRKP BSIs demonstrate comparable clinical outcomes to prolonged courses and are associated with a lower risk of subsequent candidemia.
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Antibacterianos , Carbapenémicos , Infecciones por Klebsiella , Klebsiella pneumoniae , Puntaje de Propensión , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Klebsiella pneumoniae/efectos de los fármacos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/mortalidad , Carbapenémicos/uso terapéutico , Carbapenémicos/farmacología , Antibacterianos/uso terapéutico , Resultado del Tratamiento , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Bacteriemia/mortalidad , Candidemia/tratamiento farmacológico , Candidemia/mortalidad , Candidemia/microbiología , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Farmacorresistencia Bacteriana MúltipleRESUMEN
OBJECTIVES: To demonstrate the feasibility of better diagnosing young adults with chronic nonspecific low back pain (CNLBP) by measuring water content in paraspinal muscles using water-muscle decomposition technique in dual-energy CT (DECT) and T2-mapping in MRI. METHODS: This prospective cross-sectional study included 110 young individuals (56 with CNLBP at age of 25.7 ± 2.0 years and 54 of asymptomatic at age of 25.1 ± 1.9 years) who underwent both MRI and DECT on the spine. T2 values on T2 mapping in MRI and water density (WD) value on water(muscle) images in DECT were generated at the L1-L4 levels for erector spinae muscle and L2-L5 for multifidus muscle. Pain duration time, Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) were recorded for CNLBP patients. Difference of T2 value and WD between the two patient groups, and correlations between T2 value and WD, and T2 value and WD with clinical indicators were analyzed. RESULTS: Compared with asymptomatic participants, the mean WD of multifidus muscle at L4-L5 and mean T2 values of multifidus muscle at L5 were significantly higher in CNLBP patients (all P < 0.05). T2 values had moderate to strong positive correlations (r = 0.34-0.60, all P < 0.05) with DECT WD in CNLBP patients and healthy volunteers. There was a weak correlation between VAS and WD in L5-level multifidus muscle (r = 0.29, P < 0.05). CONCLUSIONS: The T2 values in MRI and WD in DECT are higher in multifidus muscles of lower vertebra levels for young CNLBP patients, and there exists positive correlation between WD and T2 values, providing useful information for diagnosing CNLBP.
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Dolor de la Región Lumbar , Imagen por Resonancia Magnética , Músculos Paraespinales , Tomografía Computarizada por Rayos X , Humanos , Masculino , Dolor de la Región Lumbar/diagnóstico por imagen , Femenino , Músculos Paraespinales/diagnóstico por imagen , Adulto , Imagen por Resonancia Magnética/métodos , Estudios Prospectivos , Estudios Transversales , Tomografía Computarizada por Rayos X/métodos , Adulto Joven , Agua Corporal/diagnóstico por imagen , Dolor Crónico/diagnóstico por imagen , Estudios de FactibilidadRESUMEN
The introduction of new internal fixation devices and arthroscopic techniques has led to significant changes in the surgical treatment of tibial eminence fractures (TEFs) in children. In recent years, arthroscopic surgery has arisen as the gold standard for the treatment of TEFs. This popularity of arthroscopic techniques has reduced surgical complications and improved patient prognosis. In this paper, we investigate the current situation of the use of arthroscopic fixation techniques for pediatric TEFs. We searched the PubMed database using the terms "arthroscopic treatment and tibial eminence," "arthroscopic treatment and tibial spine," "tibial eminence avulsion", "tibial spine fracture", with no limit on the year of publication. From these articles, we reviewed the use of various arthroscopic TEFs fixation techniques reported in the current literature. Overall, we found that the choice of fixation method seems to have no effect on clinical outcomes or imaging results. However, if an easy, strong fixation that is less prone to epiphyseal damage is desired, as a junior practitioner, the anchor technique should be mastered first, whereas for senior practitioners, a variety of fixation techniques for TEFs should be mastered, including anchors, sutures, and screws, so that personalized fixation can be achieved with the least amount of trauma, operative time, and complications. Higher quality studies are needed in the future to provide Useful evidence to determine the optimal fixation technique in terms of clinical outcomes, function, and complications.
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Endocarditis no Infecciosa , Neoplasias Endometriales , Humanos , Femenino , Neoplasias Endometriales/diagnóstico , Neoplasias Endometriales/patología , Neoplasias Endometriales/complicaciones , Endocarditis no Infecciosa/diagnóstico , Endocarditis no Infecciosa/diagnóstico por imagen , Endocarditis/diagnóstico , Endocarditis/complicaciones , Endocarditis/microbiología , Endocarditis/tratamiento farmacológico , Diagnóstico Diferencial , Persona de Mediana Edad , AncianoRESUMEN
OBJECTIVE: Currently, there is no simple and valid method to predict the length and size of the native anterior cruciate ligament (ACL) in each adult patient who will undergo ACL reconstruction. This study aimed to develop an imaging prediction method that can predict the length and size of ACL grafts using the intact posterior cruciate ligament (PCL), in order to enhance the graft preparation individualized sizing. METHODS: Three hundred and nineteen patients aged 18 years or older who underwent magnetic resonance imaging (MRI) of the knee at an orthopaedic clinic between September 9, 2021, and February 5, 2023, were included. The length, sagittal diameter, and coronal diameter of the ACL and PCL were measured in all patients, and F-test were performed to explore linear relationship between ligament measurements. RESULTS: Equations were established to predict a variable of the native ACL for the corresponding variable of the intact PCL (i.e., sagittal diameter of the ACL = 4.32 + 1.08 × sagittal diameter of the PCL, and coronal diameter of the ACL = 2.45 + 0.59 × coronal diameter of the PCL, length of the male ACL = 10.92 + 0.64 × length of the male PCL, length of the female ACL = 11.76 + 0.58 × length of the female PCL) (R2 = 0.532; R2 = 0.417; R2 = 0.488; R2 = 0.509; respectively). CONCLUSIONS: The length and size of the intact PCL in cases without PCL buckling are predictors of the length and size of the native ACL in adults, respectively. The use of this information to optimize graft diameter may lower the rates of ACL graft failure in the future.
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Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Posterior , Adulto , Humanos , Masculino , Femenino , Ligamento Cruzado Anterior , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Ligamento Cruzado Posterior/cirugía , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/patología , Imagen por Resonancia Magnética , ChinaRESUMEN
The mitochondrial quality control system is crucial in maintaining cellular homeostasis during environmental stress. Granulosa cells are the main cells secreting steroid hormones, and mitochondria are the key organelles for steroid hormone synthesis. The impact of the mitochondrial quality control system on granulosa cells' steroid hormone synthesis and survival under heat stress is still unclear. Here, we showed that acute heat stress induces mitochondrial damage and significantly increases the number of mitophagy-like vesicles in the cytoplasm of duck ovary granulosa cells at the ultra-structural level. Meanwhile, we also found heat stress significantly increased mitochondrial fission and mitophagy-related protein expression levels both in vivo and in vitro. Furthermore, by confocal fluorescence analysis, we discovered that LC3 was distributed spot-like manner near the nucleus in the heat treatment group, and the LC3 spots and lysosomes were colocalized with Mito-Tracker in the heat treatment group. We further detected the mitophagy-related protein in the cytoplasm and mitochondria, respectively. Results showed that the PINK1 protein was significantly increased both in cytoplasm and mitochondria, while the LC3-â ¡/LC3-â ratio increase only occurred in mitochondrial. In addition, the autophagy protein induced by acute heat treatment was effectively inhibited by the mitophagy inhibitor CysA. Finally, we demonstrated that the alteration of cellular mitophagy by siRNA interference with Drp1 and PINK1 inhibited the steroid synthesis of granulosa cells and increased cell apoptosis. Study provides strong evidence that the Drp1 regulated PINK1-dependent mitophagy pathway protects follicular granulosa cells from acute heat stress-induced injury.
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Patos , Mitofagia , Femenino , Animales , Patos/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/farmacología , Pollos/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Células de la Granulosa/metabolismo , Hormonas , Respuesta al Choque Térmico , Esteroides/farmacologíaRESUMEN
BACKGROUND: To determine the clinical efficacy of rotator cuff suture and arthroscopic 360° capsular release in patients with rotator cuff tendinopathy to improve the Constant-Murley and Visual Analogue Scale (VAS) scores, and shoulder flexion. METHODS: Fifty-one patients with full-thickness rotator cuff tears and limited shoulder movement who were admitted to our hospital from October 2017 to October 2020 were selected; all patients were treated with arthroscopic rotator cuff suture and 360° capsular release. The Constant-Murley score, VAS score, and shoulder flexion angle were used to evaluate shoulder joint function before and during follow-up. Rotator cuff healing was assessed by MRI with the Sugaya classification. RESULTS: After treatment, the Constant-Murley score (58.98 ± 9.84) was significantly improved compared with pre-treatment (29.33 ± 9.71), the VAS score (1.23 ± 0.87) was significantly lower than pre-treatment (7.54 ± 1.22), and the shoulder flexion angle (142.67 ± 8.59°) was significantly improved compared with pre-treatment (51.50 ± 2.10°); the difference was statistically significant (P < 0.05). CONCLUSIONS: Arthroscopic rotator cuff suture and simultaneous 360° capsular release have a significant effect on the treatment of rotator cuff tear with limited shoulder movement.
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Lesiones del Manguito de los Rotadores , Articulación del Hombro , Humanos , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/cirugía , Hombro/cirugía , Liberación de la Cápsula Articular , Articulación del Hombro/cirugía , Artroscopía , Resultado del Tratamiento , Rango del Movimiento Articular , SuturasRESUMEN
BACKGROUND: With the aging population of society, the incidence rate of osteoporosis is increasing year by year. Early diagnosis of osteoporosis plays a significant role in the progress of disease prevention. As newly developed technology, computed tomography (CT) radiomics could discover radiomic features difficult to recognize visually, providing convenient, comprehensive and accurate osteoporosis diagnosis. This study aimed to develop and validate a clinical-radiomics model based on the monochromatic imaging of single source dual-energy CT for osteoporosis prediction. METHODS: One hundred sixty-four participants who underwent both single source dual-energy CT and quantitative computed tomography (QCT) lumbar-spine examination were enrolled in a study cohort including training datasets (n = 114 [30 osteoporosis and 84 non-osteoporosis]) and validation datasets (n = 50 [12 osteoporosis and 38 non-osteoporosis]). One hundred seven radiomics features were extracted from 70-keV monochromatic CT images. With QCT as the reference standard, a radiomics signature was built by using least absolute shrinkage and selection operator (LASSO) regression on the basis of reproducible features. A clinical-radiomics model was constructed by incorporating the radiomics signature and a significant clinical predictor (age) using multivariate logistic regression analysis. Model performance was assessed by its calibration, discrimination and clinical usefulness. RESULTS: The radiomics signature comprised 14 selected features and showed good calibration and discrimination in both training and validation cohorts. The clinical-radiomics model, which incorporated the radiomics signature and a significant clinical predictor (age), also showed good discrimination, with an area under the receiver operating characteristic curve (AUC) of 0.938 (95% confidence interval, 0.903-0.952) in the training cohort and an AUC of 0.988 (95% confidence interval, 0.967-0.998) in the validation cohort, and good calibration. The clinical-radiomics model stratified participants into groups with osteoporosis and non-osteoporosis with an accuracy of 94.0% in the validation cohort. Decision curve analysis (DCA) demonstrated that the radiomics signature and the clinical-radiomics model were clinically useful. CONCLUSIONS: The clinical-radiomics model incorporating the radiomics signature and a clinical parameter had a good ability to predict osteoporosis based on dual-energy CT monoenergetic imaging.
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Nomogramas , Tomografía Computarizada por Rayos X , Humanos , Anciano , Tomografía Computarizada por Rayos X/métodos , Envejecimiento , Curva ROC , Estudios RetrospectivosRESUMEN
Background: There were limited studies that directly compare the outcomes of various mind-body exercise (MBE) therapies on chronic non-specific low back pain (CNLBP). Objectives: To compare the efficacy of the four most popular MBE modes [Pilates, Yoga, Tai Chi (TC), and Qigong] in clinically CNLBP patients, we conducted a systematic review and network meta-analysis (NMA). Methods: We searched databases for eligible randomized controlled trials (RCTs) (from origin to July 2022). RCTs were eligible if they included adults with CNLBP, and implemented one or more MBE intervention arms using Pilates, yoga, TC, and qigong. In addition, pain intensity and physical function were evaluated using validated questionnaires. Results: NMA was carried out on 36 eligible RCTs involving 3,050 participants. The effect of exercise therapy on pain was in the following rankings: Pilates [Surface under cumulative ranking (SUCRA) = 86.6%], TC (SUCRA = 77.2%), yoga (SUCRA = 67.6%), and qigong (SUCRA = 64.6%). The effect of exercise therapy on function: Pilates (SUCRA = 98.4%), qigong (SUCRA = 61.6%,), TC (SUCRA = 59.5%) and yoga (SUCRA = 59.0%). Conclusion: Our NMA shows that Pilates might be the best MBE therapy for CNLBP in pain intensity and physical function. TC is second only to Pilates in improving pain in patients with CNLBP and has the value of promotion. In the future, we need more high-quality, long-term follow-up RCTs to confirm our findings. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=306905, identifier: CRD42022306905.
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Data mining is an analytical method for revealing the implicit internal relations among the data elements, and is also widely used in the field of acupuncture and moxibustion of traditional Chinese medicine. However, there exist some significant deficits in the rationality of design and implementation, preciseness, repeatability, comprehensiveness, objectivity and depth of insights in some current acupuncture data mining researches. In the present paper, we summarized the literature on acupuncture data mining published in the past five years, and analyzed their common shortcomings in the design, implementation and reporting process, including too broad research scope, fuzzy and limited descriptions about the inclusion criteria, not definite retrieval scope and strategy, rarely seen original researches about the assessment of the report quality, lack of detailed descriptions about the literature screening and data processing procedure, incomplete narration about the research outcomes and their clinical significance, and lack of comprehensiveness and subjectiveness and available coping strategies in the discussion of the research papers, etc., in order to promote the improvement of literature methodology and quality of acupuncture data mining research, and then improve the reliability and clinical reference value of such research results.
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Terapia por Acupuntura , Moxibustión , Reproducibilidad de los Resultados , Minería de Datos , Medicina Tradicional ChinaRESUMEN
Background: Chronic pain is often accompanied by emotional dysfunction. Transcranial direct current stimulation (tDCS) has been used for reducing pain, depressive and anxiety symptoms in chronic pain patients, but its therapeutic effect remains unknown. Objectives: To ascertain the treatment effect of tDCS on pain, depression, and anxiety symptoms of patients suffering from chronic pain, and potential factors that modulate the effectiveness of tDCS. Methods: Literature search was performed on PubMed, Embase, Web of Science, and Cochrane Library from inception to July 2022. Randomized controlled trials that reported the effects of tDCS on pain and depression and anxiety symptoms in patients with chronic pain were included. Results: Twenty-two studies were included in this review. Overall pooled results indicated that the use of tDCS can effectively alleviate short-term pain intensity [standard mean difference (SMD): -0.43, 95% confidence interval (CI): -0.75 to -0.12, P = 0.007] and depressive symptoms (SMD: -0.31, 95% CI, -0.47 to -0.14, P < 0.001), middle-term depressive symptoms (SMD: -0.35, 95% CI: -0.58 to -0.11, P = 0.004), long-term depressive symptoms (ES: -0.38, 95% CI: -0.64 to -0.13, P = 0.003) and anxiety symptoms (SMD: -0.26, 95% CI: -0.51 to -0.02, P = 0.03) compared with the control group. Conclusion: tDCS may be an effective short-term treatment for the improvement of pain intensity and concomitant depression and anxiety symptoms in chronic pain patients. Stimulation site, stimulation frequency, and type of chronic pain were significant influence factors for the therapeutic effect of tDCS. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=297693, identifier: CRD42022297693.
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Oxygen-enriched combustion (OEC) technology in SI engines can greatly improve the degree of constant volume combustion, increase the torque output, and reduce HC and CO emissions but lead to a sharp increase in NO x emissions. Simultaneously, the high temperature from OEC would lead to high nucleation particle emissions. Under the OEC mode, except the oxygen content, spark timing and engine load are important influencing factors on emissions. Exhaust gas recirculation (EGR) technology has been proven to reduce NO x emissions effectively. This research investigates the effects of EGR on combustion and emission performance under an oxygen-enriched ratio (OER) of 25% with five EGR ratios (0-20%) for the initial throttle opening of 14% (at an EGR ratio of 0%) with an engine speed of 1500 rpm. The study shows that when the OER is 25%, the output torque increases with the increase of the EGR ratio. At the proper spark timing, the EGR ratio over 15% can obtain lower NO x emissions and particle emissions than the baseline (OER of 21%). Although HC emissions increase with the EGR ratio, they are still lower than the baseline. Overall, the OER of 25% coupled with the EGR ratios of 15-20% is the predominant combustion mode to improve power and emission performance in SI engines.
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OBJECTIVE: Diffusion tensor imaging research on the anterior cruciate ligament (ACL) is limited, and no study has revealed the ACL fibrous microstructure by 7.0-Tesla magnetic resonance imaging. Therefore, we used magnetic resonance imaging to assess the ACL. METHODS: Eight porcine ACLs were investigated by diffusion tensor imaging. Imaging was performed with a 7.0-Tesla scanner using a diffusion-weighted two-dimensional spin-echo echo-planar imaging pulse sequence optimised for muscle. The diffusion tensor eigenparameters, fractional anisotropy (FA), and apparent diffusion coefficient (ADC) were used for bones and muscles. Three-dimensional projection maps of the principal eigenvectors were plotted to visualise the microstructure. RESULTS: The mean FA and ADC for the ACL were 0.27 ± 0.079 and 0.0012 ± 0.0005, respectively. There were no significant differences between the values in the proximal and distal portions . However, the ADC was smaller in the centre than on the sides (0.0015 ± 0.0007), and the mean FA was larger in the centre than on the sides (0.42 ± 0.23). The ACL fibres were parallel on the proximal and distal sides but interweaved in the centre. CONCLUSIONS: These findings may be beneficial for artificial ligaments.
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Ligamento Cruzado Anterior , Imagen de Difusión Tensora , Porcinos , Animales , Ligamento Cruzado Anterior/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Anisotropía , Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia MagnéticaRESUMEN
Purpose: To investigate the relationship between paraspinal muscles fat content and lumbar bone mineral density (BMD). Methods: A total of 119 participants were enrolled in our study (60 males, age: 50.88 ± 17.79 years, BMI: 22.80 ± 3.80 kg·m-2; 59 females, age: 49.41 ± 17.69 years, BMI: 22.22 ± 3.12 kg·m-2). Fat content of paraspinal muscles (erector spinae (ES), multifidus (MS), and psoas (PS)) were measured at (ES L1/2-L4/5; MS L2/3-L5/S1; PS L2/3-L5/S1) levels using dual-energy computed tomography (DECT). Quantitative computed tomography (QCT) was used to assess BMD of L1 and L2. Linear regression analysis was used to assess the relationship between BMD of the lumbar spine and paraspinal muscles fat content with age, sex, and BMI. The variance inflation factor (VIF) was used to detect the degree of multicollinearity among the variables. P < .05 was considered to indicate a statistically significant difference. Results: The paraspinal muscles fat content had a fairly significant inverse association with lumbar BMD after controlling for age, sex, and BMI (adjusted R 2 = 0.584-0.630, all P < .05). Conclusion: Paraspinal muscles fat content was negatively associated with BMD.Paraspinal muscles fatty infiltration may be considered as a potential marker to identify BMD loss.
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We report a C-N cross-coupling reaction of weakly nucleophilic N-arylsulfonamides and aryl bromides to access N,N-diarylsulfonamides using Ni(cod)(DQ) as a catalyst without additional ligands. The process is compatible with electron-deficient and electron-rich aryl and heteroaryl bromides (34 examples, 21-98%) and can be applied to the derivatization of an N-arylsulfonamide pharmaceutical compound.
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Bromuros , Paladio , Benzoquinonas , Catálisis , Ligandos , Preparaciones FarmacéuticasRESUMEN
Wheat powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is one of the most serious wheat diseases in the world. Biological control is considered an environmentally safe approach to control plant diseases. Here, to develop effective biocontrol agents for controlling wheat powdery mildew, antagonistic strain XZ16-1 was isolated and identified as Bacillus subtilis based on the morphological, biochemical, and physiological characteristics and 16S rDNA sequence. The culture filtrate of B. subtilis XZ16-1 and its extracts had a significant inhibitory effect on the spore germination of Bgt. Moreover, the therapeutic and prevention efficacy of the 100% culture filtrate on wheat powdery mildew reached 81.18 and 83.72%, respectively, which was better than that of chemical fungicide triadimefon. Further antimicrobial mechanism analysis showed that the XZ16-1 culture filtrate could inhibit the development of powdery mildew spores by disrupting the cell membrane integrity, causing reductions in the mitochondrial membrane potential, and inducing the accumulation of reactive oxygen species in the spores. Biochemical detection indicated that XZ16-1 could solubilize phosphate, fix nitrogen, and produce hydrolases, lipopeptides, siderophores, and indole-3-acetic acid. Defense-related enzymes activated in wheat seedlings treated with the culture filtrate indicated that disease resistance was induced in wheat to resist pathogens. Furthermore, a 106 CFU/ml suspension of XZ16-1 increased the height, root length, fresh weight, and dry weight of wheat seedlings by 77.13, 63.46, 76.73, and 19.16%, respectively, and showed good growth-promotion properties. This study investigates the antagonistic activity and reveals the action mechanism of XZ16-1, which can provide an effective microbial agent for controlling wheat powdery mildew.
Asunto(s)
Ascomicetos , Bacillus subtilis , Triticum/genética , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/genética , Ascomicetos/fisiología , Erysiphe , Resistencia a la Enfermedad/genéticaRESUMEN
Background: Aging is a significant risk factor in chronic pain development with extensive disability and greater health care costs. Mind-body exercise (MBE) has been scientifically proven to affect the pain intensity and physical health. Objectives: To assess the effects of MBE modes (Tai Chi, yoga, and qigong) for treating chronic pain among middle-aged and old people, compared with nonactive and active treatment, as well as function, quality of life, and adverse events. Methods: We searched PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang Database, and Chinese Scientific Journals Full-Text Database (VIP) till March 2022. No restrictions were chartered within the year and language of publication. We included randomized controlled trials of MBE treatment in middle-aged and elderly people with chronic pain. The overall certainty of evidence was evaluated by using the GRADE approach. Results: A total of 17 studies (n = 1,332) were included in this review. There was low-certainty evidence indicating that MBE had a moderate effect on reducing pain compared with the nonactive and active control group (standard mean difference (SMD): -0.64, 95% confidence interval (CI): -0.86 to -0.42, P < 0.001). Very-low-certainty evidence showed that the pooled SMD for the functional improvement was -0.75 (95% CI: -1.13 to -0.37, P < 0.001). Low-certainty evidence presented that no influence was observed in physical component summary (SMD: 0.23, 95% CI: -0.16 to 0.62, P = 0.24) and mental component summary (SMD: -0.01, 95% CI -0.39 to 0.36, P = 0.95). Conclusion: Our results indicated that MBE was an effective treatment for reducing symptoms of middle-aged and elderly people with chronic pain compared with nonactive and active control groups. TC and qigong had obvious benefits for knee osteoarthritis in self-reported function, but the efficacy of chronic low back pain was uncertain. No significant benefit of MBE on quality of life in older adults with chronic pain was found. More high-quality RCTs should be conducted to explore the efficacy and mechanism of MBE on chronic pain in middle-aged and elderly people from various dimensions, such as affective and cognitive dimensions. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=316591, identifier CRD42022316591.