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1.
Curr Med Imaging ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38988162

RESUMEN

OBJECTIVES: to predict liver injury in acute pancreatitis (AP) patients by establishing a radiomics model based on contrast-enhanced computed tomography (CECT). METHODS: a total of 1223 radiomic features were extracted from late arterial-phase pancreatic CECT images of 209 AP patients (146 in the training cohort and 63 in the test cohort), and the optimal radiomic features retained after dimensionality reduction by least absolute shrinkage and selection operator (LASSO) were used to construct a radiomic model through logistic regression analysis. In addition, clinical features were collected to develop a clinical model, and a joint model was established by combining the best radiomic features and clinical features to evaluate the practicality and application value of the radiomic models, clinical model and combined model. RESULTS: four potential features were selected from the pancreatic parenchyma to construct the radiomic model, and the area under the receiver operating characteristic curve (AUC) of the radiomic model was significantly greater than that of the clinical model for both the training cohort (0.993 vs. 0.653, p = 0.000) and test cohort (0.910 vs. 0.574, p = 0.000). The joint model had a greater AUC than the radiomics model for both the training cohort (0.997 vs. 0.993, p = 0.357) and test cohort (0.925 vs. 0.910, p = 0.302). CONCLUSIONS: the radiomic model based on CECT has good performance in predicting liver injury in AP patients and can guide clinical decision-making and improve the prognosis of patients with AP.

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2.
Dermatol Surg ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028841

RESUMEN

BACKGROUND: Despite numerous therapeutic modalities for vitiligo, their efficacy varies. Managing vitiligo affecting the hands poses a particularly intricate challenge, with outcomes trailing those in other anatomical regions. OBJECTIVE: Assess the determinants influencing the efficacy and safety of autocultured tissue engineering epidermal sheets transplantation in treating hand vitiligo, observed over a 6-month follow-up period. METHODS: A retrospective analysis was conducted on 33 patients who underwent treatment for hand vitiligo using autocultured tissue engineering epidermal sheets transplantation. Repigmentation extent was evaluated by 2 dermatologists. RESULTS: The cohort comprised 33 patients, including 24 males and 9 females, with an average age of 26.91 ± 9.24 years (range: 10-49 years). The mean duration of the disease was 11.61 ± 7.83 years (range: 1.5-34 years). Vitiligo lesion stability ranged from 6 months to 4 years, with an average duration of stability calculated at 1.715 ± 1 year. After 6 months, 75.8% (25/33) of patients exhibited a favorable response, with 39.4% (13/33) showing complete or near-complete repigmentation. No adverse events, such as infections or scar formation, were recorded. CONCLUSION: The authors' investigation suggests that autocultured tissue engineering epidermal sheets transplantation is a highly effective and safe therapeutic approach for hand vitiligo, offering a promising treatment avenue.

3.
Materials (Basel) ; 17(11)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38893857

RESUMEN

Robotic Friction Stir Welding (RFSW) technology integrates the advantages of friction stir welding and industrial robots, finding extensive applications and research in aerospace, shipbuilding, and new energy vehicles. However, the high-speed rotational process of friction stir welding combined with the low stiffness characteristics of serial industrial robots inevitably introduces vibrations during the welding process. This paper investigates the vibration patterns and impacts during the RFSW process and proposes an active vibration avoidance control method for variable speed welding based on constant heat input. This method utilizes a vibration feedback strategy that adjusts the spindle speed actively if the end-effector's vibration exceeds a threshold, thereby avoiding the modal frequencies of the robot at its current pose. Concurrently, it calculates and adjusts the welding speed of the robot according to the thermal equilibrium equation to maintain constant heat input. A simplified dynamic model of the RFSW robot was established, and the feasibility of this method was validated through simulation experiments. This study fills the gap in vibration analysis of RFSW and provides new insights into control strategies and process optimization for robotic friction stir welding.

4.
Pediatr Pulmonol ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771197

RESUMEN

OBJECTIVE: Bronchopulmonary dysplasia (BPD) is the most common chronic morbidity in extremely preterm infants. Mesenchymal stem cells-derived exosomes (MSC-Exos) therapies have shown prospects in animal models of BPD. Our study aimed to evaluate the effect of adipose mesenchymal stem cells-derived exosomes (AMSC-Exos) on BPD and the role of the NF-κB signaling pathway in this process. METHODS: The AMSCs were extracted and AMSC-Exos were isolated by ultracentrifugation method. Newborn rats were exposed to hyperoxia (90% O2) continuously for 7 days to establish a BPD model. The rats were treated with AMSC-Exos by intratracheal administration on postnatal day 4 (P4). Pulmonary morphology, pulmonary vasculature, inflammatory factors, and NF-κB were assessed. Hyperoxia-induced primary type II alveolar epithelial cells (AECIIs) and AMSC-Exos treatment with or without a pan-NF-κB inhibitor (PDTC) were established to explore the potential mechanism. RESULTS: Hyperoxia-exposed rats showed alveolar simplification with decreased radial alveolar count and increased mean linear intercept, low CD31, and vascular endothelial growth factor expression, reduced microvessel density, increased the expression of TNF-α, IL-1ß, and IL-6 and decreased the expression of IL-10, and induced NF-κB phosphorylation. AMSC-Exos protected the neonatal lung from the hyperoxia-induced arrest of alveolar and vascular development, alleviated inflammation, and inhibited NF-κB phosphorylation. Hyperoxia decreased viability, increased apoptosis, enhanced inflammation, and induced NF-κB phosphorylation of AECIIs but improved by AMSC-Exos, PDTC, or AMSC-Exos+PDTC. The effect of AMSC-Exos+PDTC in AECIIs was the same as AMSC-Exos, but more notable than PDTC alone. CONCLUSION: AMSC-Exos attenuated the hyperoxia-induced lung injury in neonatal rats by inhibiting the NF-κB signaling pathway partly.

5.
Ren Fail ; 46(1): 2322037, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38445367

RESUMEN

BACKGROUND: Acute kidney injury (AKI) is a frequent complication of severe acute pancreatitis (SAP). Previous investigations have revealed the involvement of FTO alpha-ketoglutarate-dependent dioxygenase (FTO) and aquaporin 3 (AQP3) in AKI. Therefore, the aim of this study is to explore the association of FTO and AQP3 on proximal tubular epithelial cell damage in SAP-induced AKI. METHODS: An in-vitro AKI model was established in human proximal tubular epithelial cells (PTECs) HK-2 via tumor necrosis factor-α (TNF-α) induction (20 ng/mL), after which FTO and AQP3 expression was manipulated and quantified by quantitative real-time PCR and Western blotting. The viability and apoptosis of PTECs under various conditions, and reactive oxygen species (ROS), superoxide dismutase (SOD), and malonaldehyde (MDA) levels within these cells were measured using commercial assay kits and flow cytometry. Methylated RNA immunoprecipitation and mRNA stability assays were performed to elucidate the mechanism of FTO-mediated N6-methyladenosine (m6A) modification. Western blotting was performed to quantify ß-catenin protein levels in the PTECs. RESULTS: FTO overexpression attenuated the TNF-α-induced decrease in viability and SOD levels, elevated apoptosis, increased levels of ROS and MDA, and diminished TNF-α-induced AQP3 expression and reduced ß-catenin expression, but its silencing led to contradictory results. FTO negatively modulates AQP3 levels in RTECs in an m6A-depednent manner and compromises AQP3 stability. In addition, all FTO overexpression-induced effects in TNF-α-induced PTECs were neutralized following AQP3 upregulation. CONCLUSION: FTO alleviates TNF-α-induced damage to PTECs in vitro by targeting AQP3 in an m6A-dependent manner.


Asunto(s)
Lesión Renal Aguda , Pancreatitis , Humanos , Enfermedad Aguda , Acuaporina 3/genética , Pancreatitis/complicaciones , Especies Reactivas de Oxígeno , Factor de Necrosis Tumoral alfa , Lesión Renal Aguda/etiología , Células Epiteliales , Superóxido Dismutasa , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética
6.
Stem Cells Transl Med ; 13(5): 415-424, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38513284

RESUMEN

BACKGROUND: Surgical intervention is the main therapy for refractory vitiligo. We developed a modified autologous cultured epithelial grafting (ACEG) technique for vitiligo treatment. Between January 2015 and June 2019, a total of 726 patients with vitiligo underwent ACEG in China, with patient characteristics and clinical factors being meticulously documented. Using a generalized linear mixed model, we were able to assess the association between these characteristics and the repigmentation rate. RESULTS: ACEG demonstrated a total efficacy rate of 82.81% (1754/2118) in treating 726 patients, with a higher repigmentation rate of 64.87% compared to conventional surgery at 52.69%. Notably, ACEG showed a better response in treating segmental vitiligo, lesions on lower limbs, age ≤ 18, and stable period > 3 years. A keratinocyte:melanocyte ratio below 25 was found to be advantageous too. Single-cell RNA sequencing analysis revealed an increase in melanocyte count and 2 subclusters of keratinocytes after ACEG, which remained higher in repigmented sites even after 1 year. CONCLUSIONS: ACEG is a promising therapy for refractory vitiligo. Patient age, clinical type, lesion site, and stability before surgery influence repigmentation in ACEG. The mechanism of repigmentation after ACEG treatment is likely not confined to the restoration of melanocyte populations. It may also involve an increase in the number of keratinocytes that support melanocyte function within the affected area. These keratinocytes may aid the post-transplant survival and function of melanocytes by secreting cytokines and extracellular matrix components. TRIAL REGISTRATION: registered with Chictr.org.cn (ChiCTR2100051405).


Asunto(s)
Trasplante Autólogo , Vitíligo , Humanos , Vitíligo/terapia , Masculino , Femenino , Estudios Retrospectivos , Trasplante Autólogo/métodos , Adulto , Adolescente , Adulto Joven , Persona de Mediana Edad , Melanocitos/trasplante , Niño , Queratinocitos/trasplante , Células Cultivadas , Epitelio
7.
Sensors (Basel) ; 24(3)2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38339719

RESUMEN

Robotic friction stir welding has become an important research direction in friction stir welding technology. However, the low stiffness of serial industrial robots leads to substantial, difficult-to-measure end-effector deviations under the welding forces during the friction stir welding process, impacting the welding quality. To more effectively measure the deviations in the end-effector, this study introduces a digital twin model based on the five-dimensional digital twin theory. The model obtains the current data of the robot and six-axis force sensor and calculates the real-time end deviations using the robot model. Based on this, a virtual welding model was realized by integrating the FEA model with the digital twin model using a co-simulation approach. This model achieves pre-process simulation by iteratively cycling through the simulated force from the FEA model and the end displacement from the robot model. The virtual welding model effectively predicts the welding outcomes with a mere 6.9% error in lateral deviation compared to actual welding, demonstrating its potential in optimizing welding parameters and enhancing accuracy and quality. Employing digital twin models to monitor, simulate, and optimize the welding process can reduce risks, save costs, and improve efficiency, providing new perspectives for optimizing robotic friction stir welding processes.

8.
Org Lett ; 26(9): 1920-1925, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38386918

RESUMEN

A photocatalytic three-component sulfonyl peroxidation of alkenes with N-sulfonyl ketimines and tert-butyl hydroperoxide is reported. The reaction takes place via the photoinduced EnT process, which allows the efficient synthesis of a variety of ß-peroxyl sulfones under mild reaction conditions in the absence of a transition metal catalyst. The downstream derivatizations of the peroxides were also performed. Furthermore, the utility of this protocol was manifested by the synthesis of 11ß-HSD1 inhibitor and the antiprostate cancer drug bicalutamide.

9.
Brain Behav ; 14(2): e3431, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38361315

RESUMEN

BACKGROUND: Intravenous thrombolysis (IVT), which is safe and effective, is the first-line therapy for acute ischemic stroke (AIS). However, its benefit for AIS patients with pre-stroke disability (PSD) is controversial. OBJECTIVE: We determined the association of PSD with the safety and efficacy of IVT among patients with AIS. METHODS: We searched PubMed, Embase, and the Cochrane Library from inception to May 23, 2022. The articles focusing on outcomes of AIS patients with PSD receiving IVT were retrieved. We used the random-effects model to pool outcomes including mortality, 24 h NIHSS improvement, symptomatic intracerebral hemorrhage (sICH), favorable functional outcome (FFO), the favorable outcome, and mortality prevalence. RESULTS: Ten studies (including 245,773 participants) that reported the outcomes of AIS patients with PSD undergoing IVT were included. In unadjusted analyses, PSD was associated with mortality (10 studies; odds ratio [OR] 1.739, 95% confidence interval [CI], 1.336-2.407), FFO (7 studies; OR 1.057, 95% CI, 1.015-1.100), 24 h NIHSS improvement (5 studies; OR .840, 95% CI, .819-.917, p = .000), and sICH (9 studies; OR .773, 95% CI, .481-1.243). In adjusted analyses, PSD was associated with mortality (seven studies; ORadj 1.789, 95% CI, 1.413-2.264), FFO (five studies; ORadj 1.087, 95% CI, 1.002-1.179), 24 h NIHSS improvement (five studies; ORadj .837, 95% CI, .799-.876), and sICH (five studies; ORadj .857, 95% CI, .725-1.012). The prevalence of FFO and mortality in patients with pre-stroke modified Rankin Scale scores of 2-5 were 49% (0.42-0.56) and 37% (0.21-0.53), respectively. CONCLUSIONS: Patients with PSD undergoing IVT had a higher mortality rate than those without PSD. Meanwhile, PSD was associated with FFO, and there was no significant difference in sICH and 24 h NIHSS improvement. High-quality data are needed to clarify the benefits of administering IVT in these patients.


Asunto(s)
Administración Intravenosa , Fibrinolíticos , Accidente Cerebrovascular Isquémico , Terapia Trombolítica , Humanos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/mortalidad , Terapia Trombolítica/métodos , Fibrinolíticos/administración & dosificación
10.
Int J Biol Macromol ; 262(Pt 1): 130257, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38423904

RESUMEN

The genus Schisandra, a member of the Magnoliaceae family, is a well-known tonic traditional Chinese medicine with a long history of traditional medicinal and functional food used in China. Polysaccharides are one of its main active constituents, which have a wide range of bioactivities, such as anti-inflammatory, anti-tumor, neuroprotection, anti-diabetes, hepatoprotection, immunomodulation, and anti-fatigue. In this paper, we review the extraction, isolation, purification, structural characterization, bioactivities, as well as structure-activity relationship of polysaccharides from the genus Schisandra. In conclusion, we hope that this review could provide reference for the subsequent research on structural, bioactivities, development and application of the genus Schisandra polysaccharides.


Asunto(s)
Ciclooctanos , Lignanos , Compuestos Policíclicos , Schisandra , Schisandra/química , Polisacáridos/química , Extractos Vegetales/química , Antioxidantes
11.
Commun Biol ; 7(1): 79, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200141

RESUMEN

Autologous cultured epithelium grafting (ACEG) presents a promising treatment for refractory vitiligo, yet concerns regarding infections and immunological reactions hinder its surgical use due to serum and feeder dependencies. Addressing this, we culture autologous epithelium under serum- and feeder-free (SFF) conditions, comparing its safety and efficacy with serum- and feeder-dependent (SFD) conditions in stable vitiligo patients, and we discover no significant differences in repigmentation between the SFF and SFD grafts. Single-cell RNA transcriptomics on SFF- and SFD-cultured epithelium alongside healthy skin reveal increased populations of LAMB3+ basal keratinocytes and ZNF90+ fibroblasts in the SFF sheets. Functional analyses showcase active cellular metabolism in LAMB3+ basal keratinocytes, vital in extracellular matrix homeostasis, while ZNF90+ fibroblasts demonstrate increased differentiation, essential in collagen formation for cell adhesion. Importantly, these cell populations in SFF sheets exhibit enhanced interactions with melanocytes compared to SFD sheets. Further, knockdown experiments of LAMB3 in keratinocytes and ZNF90 in fibroblasts lead to a downregulation in melanocyte ligand-receptor-related genes. Overall, SFF sheets demonstrate comparable efficacy to SFD sheets, offering superior safety. LAMB3+ basal keratinocytes and ZNF90+ fibroblasts act as potential drivers behind repigmentation in ACEG under SFF conditions. This study provides translational insights into ACEG repigmentation and potential therapeutic targets for vitiligo.


Asunto(s)
Vitíligo , Humanos , Vitíligo/terapia , Epitelio , Queratinocitos , Piel , Fibroblastos
12.
Clin Neurol Neurosurg ; 236: 108096, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38181677

RESUMEN

PURPOSE: We acknowledge that between endovascular treatment (EVT) has emerged as a promising therapeutic approach, with some evidence of benefits observed in clinical trials. However, there remains a significant gap in the evidence regarding the real-world application and effectiveness of EVT.The objective of this study was to comprehensively evaluate the safety and efficacy differences between EVT and standard medical treatment (SMT) in patients with basilar artery occlusion(BAO). METHODS: Real-world studies (RWSs) on patients with BAO who underwent EVT and SMT were identified through searches in EMBASE, PubMed, and Cochrane Library databases. The efficacy outcomes included good clinical outcomes [defined as modified Rankin Scale (mRS) scores of 0-3 at 90 days], excellence clinical outcomes (defined as mRS scores of 0-2 at 90 days), 90-day mortality rate, and reperfusion status. The safety outcome was symptomatic intracranial hemorrhage (sICH). Subgroup analysis was conducted based on study type (prospective and retrospective studies). The relationship between EVT and SMT with the prognosis of BAO patients was expressed using odds ratios (OR) with a 95% confidence interval (95% CI). RESULTS: The seven studies involved a total of 2885 patients. After conducting sensitivity analysis and excluding articles with high heterogeneity, EVT demonstrated a significant association with good clinical outcomes at 90 days (OR=4.01, 95% CI: 2.60-6.19) and excellence clinical outcomes at 90 days (OR=5.70, 95% CI: 3.18-10.22) compared to SMT. Additionally, EVT showed a lower correlation with 90-day mortality rate compared to the SMT group (OR=0.35, 95% CI: 0.25-0.47). Subgroup analysis based on study type revealed that EVT had higher rates of successful reperfusion (retrospective study group: OR=7.97, 95% CI: 4.83-13.15; prospective study group: OR=51.57, 95% CI: 29.76-89.38) than the SMT group in both subgroups. The presence of sICH was not statistically significant in the retrospective study group (OR=1.20, 95% CI: 0.58-2.48) and showed high heterogeneity. However, in the prospective study group, EVT exhibited a higher risk of bleeding compared to SMT (OR=11.42, 95% CI: 2.65-49.20). CONCLUSIONS: In summary, our real-world study aligns with the conclusions of recently published randomized controlled trials research. When comparing EVT and SMT in the treatment of BAO, EVT shows a higher correlation with favorable clinical outcomes, higher rates of successful reperfusion, and lower mortality rates. However, it does come with an increased risk of sICH.


Asunto(s)
Arteriopatías Oclusivas , Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/terapia , Estudios Retrospectivos , Estudios Prospectivos , Arteria Basilar , Resultado del Tratamiento , Arteriopatías Oclusivas/complicaciones , Hemorragias Intracraneales/etiología , Procedimientos Endovasculares/efectos adversos , Trombectomía/efectos adversos
13.
Mol Neurobiol ; 61(4): 2033-2048, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37843800

RESUMEN

Surfeit locus protein 4 (SURF4) functions as a cargo receptor that is capable of transporting newly formed proteins from the lumen of the endoplasmic reticulum into vesicles and Golgi bodies. However, the role of SURF4 in the central nervous system remains unclear. The aim of this study is to investigate the role of SURF4 and its underlying mechanisms in cerebral ischemia/reperfusion (I/R) injury in rats, and whether it can be used effectively for novel therapeutic intervention. We also examined whether transcranial direct-current stimulation (tDCS) can exert a neuroprotective effect via SURF4-dependent signalling. Following cerebral I/R injury in rats, a significant increase was observed in the expression of SURF4. In both I/R injury and oxygen-glucose deprivation (OGD) insult, suppressing the expression of SURF4 demonstrated a neuroprotective effect, while overexpression of SURF4 resulted in increased neuronal death. We further showed that the levels of nerve growth factor precursor (proNGF), p75 neurotrophin receptor (p75NTR), sortilin, and PTEN were increased following cerebral I/R injury, and that SURF4 acted through the PTEN/proNGF signal pathway to regulate neuronal viability. We demonstrated that tDCS treatment reduced SURF4 expression and decreased the infarct volume after cerebral I/R injury. Together, this study indicates that SURF4 plays a critical role in ischemic neuronal injury and may serve as a molecular target for the development of therapeutic strategies in acute ischemic stroke.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Fármacos Neuroprotectores , Daño por Reperfusión , Estimulación Transcraneal de Corriente Directa , Ratas , Animales , Fármacos Neuroprotectores/farmacología , Oxígeno/metabolismo , Daño por Reperfusión/metabolismo , Isquemia Encefálica/metabolismo , Apoptosis , Infarto de la Arteria Cerebral Media/metabolismo
14.
Brain Res ; 1825: 148724, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38110073

RESUMEN

Phosphoglycerate kinase 1 (PGK1) is extensively located in the cytosol and mitochondria. The role of PGK1 in ischemic neuronal injury remains elusive. In the in vitro model of oxygen-glucose deprivation/reoxygenation (OGD/R), we showed that PGK1 expression was increased in cortical neurons. Knockdown of PGK1 led to a reduction of OGD/R-induced neuronal death. The expression of cytosolic PGK1 was reduced, but the levels of mitochondrial PGK1 were increased in OGD/R-insulted neurons. Inhibiting the activity of mitochondrial PGK1 alleviated the neuronal injury after OGD/R insult. We further showed that the protein levels of TBC domain family member 15 (TBC1D15) were decreased in OGD/R-insulted neurons. Knockdown of TBC1D15 led to increased levels of mitochondrial PGK1 after OGD/R insult in cortical neurons. Moreover, increased reactive oxygen species (ROS) resulted in a reduction of TBC1D15 in OGD/R-insulted neurons. These results suggest that the upregulation of mitochondrial PGK1 by ROS-TBC1D15 signaling pathway promotes neuronal death after OGD/R injury. Mitochondrial PGK1 may act as a regulator of neuronal survival and interventions in the PGK1-dependent pathway may be a potential therapeutic strategy.


Asunto(s)
Oxígeno , Daño por Reperfusión , Humanos , Oxígeno/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Regulación hacia Arriba , Glucosa/metabolismo , Mitocondrias/metabolismo , Apoptosis , Daño por Reperfusión/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , Fosfoglicerato Quinasa/metabolismo
16.
Materials (Basel) ; 16(19)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37834597

RESUMEN

This article comprehensively explores the cross-scale effects of gravity on macroscopic flow formation and weld bead formation in variable polarity plasma arc welding. Gravity-induced changes in welding direction were achieved through welding at different spatial positions. The properties of the weld bead were investigated at various spatial locations. Additionally, an elemental tracing technique was employed to study the internal flow behavior of molten metal. In the flat welding position, there is an observable trend of increasing grain size in the welded bead, accompanied by a significant expansion of the coarse grain zone. Consequently, the properties of the weld bead in the flat position are inferior to those achieved in the vertical welding position. This phenomenon can be attributed to the accumulation of molten metal at the exit side of the keyhole, resulting in temperature accumulation. Research indicates that the internal flow within the weld pool plays a critical role in causing this phenomenon. The study's findings reveal the presence of two distinct vortex flow patterns within the weld pool: one aligned with the welding direction and the other directed towards the interior of the weld pool. Particularly noteworthy is the substantial expansion of the flow channel area in the flat welding position, which significantly amplifies the impact of internal flow. This enhanced flow intensity inevitably leads to the increased buildup of molten metal at the keyhole exit side. These studies lay the groundwork for achieving high-quality and controllable spatial-position welding.

17.
J Org Chem ; 88(17): 12630-12640, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37579302

RESUMEN

We report a new method for the synthesis of trifluoromethylated and sulfonylated oxazolines by electrochemical radical cascade cyclizations of N-allylamides with sodium trifluoromethanesulfinate or sulfonylhydrazines. This protocol provides a green and useful strategy to synthesize trifluoromethylated and sulfonylated oxazolines with a broad substrate scope under ambient conditions.

18.
Acta Pharmacol Sin ; 44(12): 2445-2454, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37580492

RESUMEN

Acute pancreatitis (AP) is an inflammatory disease of the exocrine pancreas. Disruptions in organelle homeostasis, including macroautophagy/autophagy dysfunction and endoplasmic reticulum (ER) stress, have been implicated in human and rodent pancreatitis. Syntaxin 17 (STX17) belongs to the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) subfamily. The Qa-SNARE STX17 is an autophagosomal SNARE protein that interacts with SNAP29 (Qbc-SNARE) and the lysosomal SNARE VAMP8 (R-SNARE) to drive autophagosome-lysosome fusion. In this study, we investigated the role of STX17 in the pathogenesis of AP in male mice or rats induced by repeated intraperitoneal injections of cerulein. We showed that cerulein hyperstimulation induced AP in mouse and rat models, which was characterized by increased serum amylase and lipase activities, pancreatic edema, necrotic cell death and the infiltration of inflammatory cells, as well as markedly decreased pancreatic STX17 expression. A similar reduction in STX17 levels was observed in primary and AR42J pancreatic acinar cells treated with CCK (100 nM) in vitro. By analyzing autophagic flux, we found that the decrease in STX17 blocked autophagosome-lysosome fusion and autophagic degradation, as well as the activation of ER stress. Pancreas-specific STX17 knockdown using adenovirus-shSTX17 further exacerbated pancreatic edema, inflammatory cell infiltration and necrotic cell death after cerulein injection. These data demonstrate a critical role of STX17 in maintaining pancreatic homeostasis and provide new evidence that autophagy serves as a protective mechanism against AP.


Asunto(s)
Ceruletida , Pancreatitis , Masculino , Ratones , Animales , Ratas , Humanos , Enfermedad Aguda , Ceruletida/toxicidad , Modelos Animales de Enfermedad , Pancreatitis/inducido químicamente , Autofagia/fisiología , Proteínas SNARE/metabolismo , Edema
19.
Molecules ; 28(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37513490

RESUMEN

This research presents a novel, eco-friendly, vortex-assisted liquid-liquid microextraction (VALLME) approach, integrating hydrophobic deep eutectic solvents (DESs) with HPLC for the identification and quantification of nine specific flavonoids in Shanxi aged vinegar (SAV). The parameters of DES-VALLME, including the ratio of trioctylmethylammonium chloride to 1,4-butanediol (1:6), DES volume (150 µL), vortex duration (5 min), the concentration of NaCl (0.40 g), and centrifugation time (10 min), were optimized to achieve the maximum extraction efficiency of target substances. Under these optimal conditions, quantitative analyses performed via HPLC demonstrated a broad linear range of 0.20-50.00 µg/mL and correlation coefficients (r2) greater than 0.9944 for all nine calibration curves. The limits of detection (LOD) and limits of quantitation (LOQ) were 0.09-0.18 µg/mL and 0.30-0.60 µg/mL, respectively, ensuring high sensitivity. The relative standard deviations for intra-day and inter-day variability were within the acceptable range, 2.34-3.77% and 3.04-4.96%, respectively, demonstrating the method's reliability. The recovery rates ranged from 85.97% to 108.11%, underscoring the method's precision. This technique exhibited a significant enrichment effect (enrichment factor: 43 to 296) on SAV flavonoids. Notably, the eco-friendliness of this procedure was evaluated using the Analytical Eco-Scale, Green Analytical Procedure Index, and Analytical Greenness Metric. The results suggested that this technique is a viable green alternative to traditional flavonoid determination methods in SAV. In summary, this novel method provides a theoretical basis for assessing flavonoid content in SAV samples and tracing SAV products. This contribution has significant implications for enhancing analytical techniques in food chemistry and environmental science and the sustainable development of the food industry.


Asunto(s)
Ácido Acético , Microextracción en Fase Líquida , Solventes/química , Disolventes Eutécticos Profundos , Microextracción en Fase Líquida/métodos , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Límite de Detección , Ambiente
20.
Materials (Basel) ; 16(12)2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37374676

RESUMEN

High-speed GMAW tends to be accompanied by periodic humping defects, thereby reducing the weld bead quality. A new method was proposed to actively control the weld pool flow for eliminating humping defects. A high-melting point solid pin was designed and inserted into the weld pool to stir the liquid metal during the welding process. The characteristics of the backward molten metal flow were extracted and compared by a high-speed camera. Combined with particle tracing technology, the momentum of the backward metal flow was calculated and analyzed, and the mechanism of hump suppression in high speed GMAW was further revealed. The stirring pin interacted with the liquid molten pool, resulting in a vortex zone behind the stirring pin, which significantly reduced the momentum of the backward molten metal flow, and thus it inhibited the formation of humping beads.

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