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The development of temperature-sensitive sensors upgraded by poly(N-isopropylacrylamide) (PNIPAM) represents a significant stride in enhancing performance and tailoring thermoresponsiveness. In this study, an array of temperature-responsive electrochemical sensors modified with different PNIPAM-based copolymer films were fabricated via a "coating and grafting" two-step film-forming technique on screen-printed platinum electrodes (SPPEs). Chemical composition, grafting density, equilibrium swelling, surface wettability, surface morphology, amperometric response, cyclic voltammograms, and other properties were evaluated for the modified SPPEs, successively. The modified SPPEs exhibited significant changes in their properties depending on the preparation concentrations, but all the resulting sensors showed excellent stability and repeatability. The modified sensors demonstrated favorable sensitivity to hydrogen peroxide and L-ascorbic acid. Furthermore, notable temperature-induced variations in electrical signals were observed as the electrodes were subjected to temperature fluctuations above and below the lower critical solution temperature (LCST). The ability to reversibly respond to temperature variations, coupled with the tunability of PNIPAM's thermoresponsive properties, opens up new possibilities for the design of sensors that can adapt to changing environments and optimize their performance accordingly.
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Background: The association of Remnant cholesterol (RC) with renal function and its progression in patients with Type 2 diabetes (T2DM) related chronic kidney disease (CKD) remains unclear. Methods: 8,678 patients with T2DM-related CKD were included in cross-sectional analysis, and 6,165 patients were enrolled in longitudinal analysis and followed up for a median of 36.0 months. The outcomes were renal composite endpoint event and rapid progression of renal function. Results: 24.54% developed a renal composite endpoint event, and 27.64% rapid progression of renal function. RC levels above 0.56 mmol/L independently increased the risk of both renal composite endpoint (HR, 1.17; 95% CIs, 1.03-1.33) and rapid progression of renal function (OR, 1.17; 95% CIs, 1.01- 1.37). TG levels above 1.65 mmol/L only increased the risk of renal composite endpoint (HR, 1.16; 95% CIs, 1.02 -1.32). TC levels above 5.21 mmol/L increased the risk of renal composite endpoint (HR, 1.14; 95% CIs, 1.01-1.29) only in patients with proteinuria≥0.5g/d. Conversely, HDL-C levels below 1.20 mmol/L or above 1.84 mmol/L increased the risk of rapid progression of renal function (OR, 0.88; 95% CIs, 0.70 -0.99) in patients with proteinuria<0.5g/d (all P<0.05). Conclusion: In patients with T2DM-related CKD, RC was an independent risk factor for progression of renal function, and maintaining it below 0.56 mmol/L could reduce the risk of renal function progression.
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Colesterol , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Progressão da Doença , Insuficiência Renal Crônica , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/sangue , Masculino , Feminino , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/metabolismo , Pessoa de Meia-Idade , Colesterol/sangue , Estudos Transversais , Idoso , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/fisiopatologia , Taxa de Filtração Glomerular , Estudos Longitudinais , Seguimentos , Rim/fisiopatologia , Rim/metabolismo , Fatores de RiscoRESUMO
In order to study the multi-mode damage and fracture mechanisms of thin-walled tubular parts with cross inner ribs (longitudinal and transverse inner ribs, LTIRs), the Gurson-Tvergaard-Needleman (GTN) model was modified with a newly proposed stress state function. Thus, tension damage and shear damage were unified by the new stress state function, which was asymmetric with respect to stress triaxiality. Tension damage dominated the modification, which coupled with the shear damage variable, ensured the optimal prediction of fractures of thin-walled tubular parts with LTIRs by the modified GTN model. This included fractures occurring at the non-rib zone (NRZ), the longitudinal rib (LIR) and the interface between the transverse rib (TIR) and the NRZ. Among them, the stripping of material from the outer surface of the tubular part was mainly caused by the shearing of built-up material in front of the rollers under a large wall thickness reduction (ΔT). Shear and tension deformation were the causes of fractures occurring at the NRZ, while axial tension under a large TIR interval (l) mainly resulted in fractures on LIRs. Fractures at the interface between the TIR and NRZ were due to the shearing applied by rib grooves and radial tension during the formation of ribs. This study can provide guidance for the manufacturing of high-performance aluminum alloy thin-walled tubular components with complex inner ribs.
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BACKGROUND: This study aimed to investigate the expression and clinical value of microRNA miR-486-5p in diagnosing lumbar spinal stenosis (LSS) patients and predicting the clinical outcomes after minimally invasive spinal surgery (MISS) in LSS patients, and the correlation of miR-486-5p with inflammatory responses in LSS patients. METHODS: This study included 52 LSS patients, 46 patients with lumbar intervertebral disk herniation (LDH) and 42 healthy controls. Reverse transcription quantitative PCR was used to detect miR-486-5p expression. The ability of miR-486-5p to discriminate between different groups was evaluated by receiver-operating characteristic analysis. The visual analogue scale (VAS), Oswestry Disability Index (ODI) and Japanese Orthopaedic Association (JOA) scores at 6 months postoperatively were used to reflect the clinical outcomes of LSS patients. Enzyme-linked immunosorbent assay was used to measure the levels of inflammatory factor [interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α)]. The correlation of miR-486-5p with continuous variables in LSS patients was evaluated by the Pearson correlation coefficient. RESULTS: Expression of serum miR-486-5p was upregulated in LSS patients and had high diagnostic value to screen LSS patients. In addition, serum miR-486-5p could predict the 6-month clinical outcomes after MISS therapy in LSS patients. Moreover, serum miR-486-5p was found to be positively correlated with the levels of IL-1ß and TNF-α in patients with LSS. CONCLUSION: miR-486-5p, increased in LSS patients, can function as an indicator to diagnose LSS and a predictive indicator for the clinical outcomes after MISS therapy in LSS patients. In addition, miR-486-5p may regulate LSS progression by modulating inflammatory responses.
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Vértebras Lombares , MicroRNAs , Procedimentos Cirúrgicos Minimamente Invasivos , Estenose Espinal , Humanos , Estenose Espinal/cirurgia , Estenose Espinal/genética , Estenose Espinal/sangue , MicroRNAs/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Vértebras Lombares/cirurgia , Idoso , Prognóstico , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Adulto , Interleucina-1beta/sangue , Interleucina-1beta/genéticaRESUMO
Pseudouridine is the most abundant modified nucleoside found in non-coding RNA and is widely used in biological and pharmaceutical fields. However, current methods for pseudouridine production suffer from drawbacks such as complex procedures, low efficiency and high costs. This study presents a novel enzymatic cascade reaction route in Escherichia coli, enabling the whole-cell catalytic synthesis of pseudouridine from uridine. Initially, a metabolic pathway was established through plasmid-mediated overexpression of endogenous pseudouridine-5-phosphase glycosidase, ribokinase, and ribonucleoside hydrolase, resulting in the accumulation of pseudouridine. Subsequently, highly active endogenous ribonucleoside hydrolase was screened to enhance uridine hydrolysis and provide more precursors for pseudouridine synthesis. Furthermore, modifications were made to the substrates and products transport pathways to increase the pseudouridine yield while avoiding the accumulation of by-product uridine. The resulting recombinant strain Ψ-7 catalyzed the conversion of 30 g/L uridine into 27.24 g/L pseudouridine in 24 h, achieving a conversion rate of 90.8% and a production efficiency of 1.135 g/(L·h). These values represent the highest reported yield and production efficiency achieved by enzymatic catalysis methods to date.
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Escherichia coli , Pseudouridina , Pseudouridina/genética , Pseudouridina/química , Pseudouridina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Uridina/genética , Uridina/química , Uridina/metabolismo , Catálise , Hidrolases/metabolismoRESUMO
BACKGROUND: The determination of glycosylated hemoglobin (HbA1c) is crucial for diabetes diagnosis and can provide more substantial results than the simple measurement of glycemia. While there is a lack of simple methods for the determination of HbA1c using a point-of-care test (POCT) compared to glycemia measurement. In particular, high-performance liquid chromatography (HPLC) is considered the current gold standard for determining HbA1c levels. However, commercial HPLC systems usually have some sort of disadvantages such as bulky size, high-cost and need for qualified operators. Therefore, there is an urgent demand to develop a portable, and fast HbA1c detection system consuming fewer reagents. RESULTS: We present a novel microchip that integrates a micromixer, passive injector, packed column and detection cell. The integrated microchip, in which all the microstructures were formed in the CNC machining center through micro-milling, is small in size (30 mm × 70 mm × 10 mm), and can withstand 1600 psi of liquid pressure. The integrated design is beneficial to reduce the band broadening caused by dead volume. Based on the microchip, a microchip liquid chromatography (LC) system was built and applied to the analysis of HbA1c. The separation conditions of HbA1c in blood calibrator samples were optimized using the microchip LC system. Samples containing four levels of HbA1c were completely separated within 2 min in optimal gradient conditions, with an inaccuracy (<3.2 %), a coefficient of variation (c.v. < 2.1 %) and a correlation coefficient (R2 = 0.993), indicating excellent separation efficiency and reproducibility. SIGNIFICANCE: The POCT of HbA1c is critical for diabetes diagnosis. The microchip chromatography system was developed for HbA1c determination, which contains an integrated microchip and works under a gradient elution. It surpasses existing chip technology in terms of separation performance and detection speed, providing a competitive advantage for POCT of HbA1c. It is considered one important step for realizing efficient portable systems for timely and accurate diabetes diagnosis.
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Diabetes Mellitus , Humanos , Hemoglobinas Glicadas , Reprodutibilidade dos Testes , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão/métodosRESUMO
Osteoporotic vertebral compression fracture (OVCF) is a serious complication of osteoporosis, and percutaneous vertebroplasty (PVP) is a major therapeutic method for OVCF. This study aimed to evaluate the clinical efficacy and postoperative complications of robot-assisted targeted PVP for the treatment of OVCF. The data from 202 OVCF patients were analyzed in this study, including 72 cases received traditional PVP (PVP group), 68 cases received robot-assisted PVP (R-PVP group), and 62 cases underwent robot-assisted PVP combined with targeted plugging (R-PVP + TP group). The fluoroscopic exposure conditions, operative duration, lengths of stay, postoperative bone cement leakage, refracture, Visual Analog Scale (VAS) score, and Oswestry Disability Index (ODI) score were obtained and compared between the three groups. The Kaplan-Meier method and logistic regression model were adopted to screen the risk factors related with postoperative refracture. R-PVP and R-PVP + TP group had significantly reduced fluoroscopic frequency and radiation dose, and reduced cement leakage compared with PVP group. R-PVP + TP not only showed more obvious advantages in these aspects, but also had a lower probability of postoperative refracture. In addition, BMD, fracture vertebral distribution, cement leakage, and surgery methods were independent related with refracture. All the results demonstrated robot assistance could improve the application of PVP in the treatment of OVCF, and robot-assisted PVP combined with targeted plugging showed significantly reduced fluoroscopic exposure, bone cement leakage, and rate of postoperative refracture. BMD, fracture vertebral distribution, cement leakage, and operation methods were identified as four risk factors for the onset of refracture after PVP.
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Fraturas por Compressão , Cifoplastia , Fraturas por Osteoporose , Procedimentos Cirúrgicos Robóticos , Robótica , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Fraturas por Compressão/cirurgia , Fraturas por Compressão/complicações , Fraturas por Compressão/tratamento farmacológico , Cimentos Ósseos/uso terapêutico , Vertebroplastia/efeitos adversos , Vertebroplastia/métodos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Fraturas da Coluna Vertebral/tratamento farmacológico , Cifoplastia/efeitos adversos , Cifoplastia/métodos , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Fraturas por Osteoporose/cirurgia , Fraturas por Osteoporose/complicações , Fraturas por Osteoporose/tratamento farmacológico , Resultado do Tratamento , Fatores de RiscoRESUMO
Objective: The prognostic utility of inflammatory markers in survival has been suggested in patients with cancer; however, evidence on their prognostic value in severely ill patients is very limited. We aimed to explore the prognostic value of cholinesterase (ChE), C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT) in predicting mortality in patients from the intensive care unit (ICU). Methods: Serum levels of ChE, CRP, IL-6 and PCT were measured in ICU patients from December 13th, 2019 to June 28th, 2022. We assessed the predictive power of ChE, CRP, IL-6, and PCT using the receiver operating characteristic (ROC) curves. Furthermore, we evaluated their diagnostic accuracy by comparing the areas under the ROC curve (AUCs) along with their corresponding 95% confidence intervals (CIs). The cut-off values were determined to dichotomise these biomarkers, which were then included in multivariable logistic regression models to examine their relationship with ICU mortality. Results: Among 253 ICU patients included in the study, 66 (26%) died during the ICU stay. The AUCs to predict ICU mortality were 0.643 (95% CI, 0.566-0.719), 0.648 (95% CI, 0.633-0.735), 0.643 (95% CI, 0.563-0.723) and 0.735 (95% CI, 0.664-0.807) for ChE, CRP, IL-6 and PCT, respectively. After adjusting for age, sex and disease severity, lower ChE level (<3.668 × 103 U L-1) and higher levels of CRP (>10.546 mg dL-1), IL-6 (>986.245 pg mL-1) and PCT (>0.505 µg L-1) were associated with higher mortality risk, with odd ratios of 2.70 (95% CI, 1.32-5.54), 4.99 (95% CI, 2.41-10.38), 3.24 (95% CI, 1.54-6.78) and 3.67 (95% CI, 1.45-9.95), respectively. Conclusion: ChE, CRP, IL-6 and PCT were independent ICU mortality risk factors in severely ill patients. Elevated PCT levels exhibited better predictive value than the other three biomarkers that were evaluated.
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The cardioprotective effects of sodium-glucose cotransporter type 2 (SGLT2) inhibitors have been demonstrated in many studies. However, their benefits for end-stage kidney disease patients, particularly those on peritoneal dialysis, remain unclear. SGLT2 inhibition has shown peritoneal protective effects in some studies, but the mechanisms are still unknown. Herein, we investigated the peritoneal protective mechanisms of Canagliflozin in vitro by simulating hypoxia with CoCl2 in human peritoneal mesothelial cells (HPMCs) and rats by intraperitoneal injection of 4.25% peritoneal dialysate simulating chronic high glucose exposure. CoCl2 hypoxic intervention significantly increased HIF-1α abundance in HPMCs, activated TGF-ß/p-Smad3 signaling, and promoted the production of fibrotic proteins (Fibronectin, COL1A2, and α-SMA). Meanwhile, Canagliflozin significantly improved the hypoxia of HPMCs, decreased HIF-1α abundance, inhibited TGF-ß/p-Smad3 signaling, and decreased the expression of fibrotic proteins. Five-week intraperitoneal injection of 4.25% peritoneal dialysate remarkably increased peritoneal HIF-1α/TGF-ß/p-Smad3 signaling and promoted peritoneal fibrosis and peritoneal thickening. At the same time, Canagliflozin significantly inhibited the HIF-1α/TGF-ß/p-Smad3 signaling, prevented peritoneal fibrosis and peritoneal thickening, and improved peritoneal transportation and ultrafiltration. High glucose peritoneal dialysate increased the expression of peritoneal GLUT1, GLUT3 and SGLT2, all of which were inhibited by Canagliflozin. In conclusion, we showed that Canagliflozin could improve peritoneal fibrosis and function by ameliorating peritoneal hypoxia and inhibiting the HIF-1α/TGF-ß/p-Smad3 signaling pathway, providing theoretical support for the clinical use of SGLT2 inhibitors in patients on peritoneal dialysis.
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Deformation instability is a macroscopic and microscopic phenomenon of non-uniformity and unstable deformation of materials under stress loading conditions, and it is affected by the intrinsic characteristics of materials, the structural geometry of materials, stress state and environmental conditions. Whether deformation instability is positive and constructive or negative and destructive, it objectively affects daily life at all times and the deformation instability based on metal-bearing analysis in engineering design has always been the focus of attention. Currently, the literature on deformation instability in review papers mainly focuses on the theoretical analysis of deformation instability (instability criteria). However, there are a limited number of papers that comprehensively classify and review the subject from the perspectives of material characteristic response, geometric structure response, analysis method and engineering application. Therefore, this paper aims to provide a comprehensive review of the existing literature on metal deformation instability, covering its fundamental principles, analytical methods, and engineering practices. The phenomenon and definition of deformation instability, the principle and viewpoint of deformation instability, the theoretical analysis, experimental research and simulation calculation of deformation instability, and the engineering application and prospect of deformation instability are described. This will provide a reference for metal bearing analysis and deformation instability design according to material deformation instability, structural deformation instability and localization conditions of deformation instability, etc. From the perspective of practical engineering applications, regarding the key problems in researching deformation instability, using reverse thinking to deduce and analyze the characteristics of deformation instability is the main trend of future research.
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The positive and negative effects of the participation of digital platform companies in governance are a major issue of the times. Starting from the three subfields of internal governance, external governance, and co-governance, we construct an analytical framework for digital platform governance to understand the four-sided relationship among digital platform companies, the state, the market, and society. From the perspective of enterprise autonomy, we should view the effectiveness of platform company participation in social governance dialectically. The key of promoting good platform governance is to improve the external structural pressure from the state, promote the reform of the endogenous governance of enterprises, and build a sustainable architecture for co-governance. The mission of sociologists includes not only explanation but also intervention.
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Introduction: To retrospectively investigate the clinical characteristics and risk factors of cardiac surgery associated-acute kidney injury (CS-AKI) progressed to chronic kidney disease (CKD) in adults and to evaluate the performance of clinical risk factor model for predicting CS-AKI to CKD. Methods: In this retrospective, observational cohort study, we included patients who were hospitalized for CS-AKI without a prior CKD [estimated glomerular filtration rate (eGFR) < 60â ml · min-1·1.73â m-2] at Central China Fuwai Hospital from January 2018 to December 2020. Survived patients were followed up for 90 days, the endpoint was CS-AKI to CKD, and then divided them into two groups (with or without CS-AKI to CKD). The baseline data including demographics, comorbidities, renal function, and other laboratory parameters were compared between two groups. The logistic regression model was used to analyze the risk factors for CS-AKI to CKD. Finally, receiver operator characteristic (ROC) curve was drawn to evaluate the performance of the clinical risk factor model for predicting CS-AKI to CKD. Results: We included 564 patients with CS-AKI (414 males, 150 females; age: 57.55 ± 11.86 years); 108 (19.1%) patients progressed to new-onset CKD 90 days after CS-AKI. Patients with CS-AKI to CKD had a higher proportion of females, hypertension, diabetes, congestive heart failure, coronary heart disease, low baseline eGFR and hemoglobin level, higher serum creatinine level at discharge (P < 0.05) than those without CS-AKI to CKD. Multivariate logistic regression analysis revealed that female sex(OR = 3.478, 95% CI: 1.844-6.559, P = 0.000), hypertension (OR = 1.835, 95% CI: 1.046-3.220, P = 0.034), coronary heart disease (OR = 1.779, 95% CI: 1.015-3.118, P = 0.044), congestive heart failure (OR = 1.908, 95% CI: 1.124-3.239, P = 0.017), preoperative low baseline eGFR (OR = 0.956, 95% CI: 0.938-0.975, P = 0.000), and higher serum creatinine level at discharge (OR = 1.109, 95% CI: 1.014-1.024, P = 0.000) were independent risk factors for CS-AKI to CKD. The clinical risk prediction model including female sex, hypertension, coronary heart disease, congestive heart failure, preoperative low baseline eGFR, and higher serum creatinine level at discharge produced a moderate performance for predicting CS-AKI to CKD (area under ROC curve = 0.859, 95% CI: 0.823-0.896). Conclusion: Patients with CS-AKI are at high risk for new-onset CKD. Female sex, comorbidities, and eGFR can help identify patients with a high risk for CS-AKI to CKD.
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Triglyceride-glucose (TyG) index has been proposed to be a simple, economical, and reliable marker of insulin resistance. We aimed to investigate whether TyG is an independent predictor of hyperuricemia in diabetic kidney disease (DKD) populations by conducting a cross-sectional and longitudinal study. A total of 6,471 patients were enrolled in cross-sectional analysis, and 3,634 patients without hyperuricemia at the baseline were included in longitudinal analysis and were followed up for a median of 23.0 months. Hyperuricemia was categorized as a serum uric acid level ≥ 420 umol/L (7 mg/dL). In this study, 19.58% of participants had hyperuricemia. In the cross-sectional analysis, multivariate logistics regression analysis showed that the ORs (95% CI) for hyperuricemia in the second, third, and fourth TyG quartiles were 1.40 (95% CI 0.73-2.65), 1.69 (95% CI 0.90-3.18), and 4.53 (95% CI 2.39-8.57), respectively, compared with the first quartile. Longitudinally, the Kaplan-Meier survival analysis showed that higher TyG levels predicted higher incidence of hyperuricemia. Multivariate Cox regression model revealed that the hazard ratios for hyperuricemia in the upper quartiles of the TyG index were 1.69 (95% CI 0.97-2.93), 2.23 (95% CI 1.33-3.75), and 2.50 (95% CI 1.46-4.27), respectively, compared with the first quartile. Moreover, the subgroup analyses revealed that the relationship between TyG levels and hyperuricemia was robust in DKD patients. Our findings indicate a significant independent correlation between the TyG index and the risk of hyperuricemia in DKD patients.
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Diabetes Mellitus , Nefropatias Diabéticas , Hiperuricemia , Humanos , Triglicerídeos , Glucose , Hiperuricemia/complicações , Nefropatias Diabéticas/etiologia , Glicemia/análise , Estudos Transversais , Estudos Longitudinais , Ácido Úrico , Fatores de RiscoRESUMO
BACKGROUND: 5-hydroxytryptophan (5-HTP), the direct biosynthetic precursor of the neurotransmitter 5-hydroxytryptamine, has been shown to have unique efficacy in the treatment of a variety of disorders, including depression, insomnia, and chronic headaches, and is one of the most commercially valuable amino acid derivatives. However, microbial fermentation for 5-HTP production continues to face many challenges, including low titer/yield and the presence of the intermediate L-tryptophan (L-Trp), owing to the complexity and low activity of heterologous expression in prokaryotes. Therefore, there is a need to construct an efficient microbial cell factory for 5-HTP production. RESULTS: We describe the systematic modular engineering of wild-type Escherichia coli for the efficient fermentation of 5-HTP from glucose. First, a xylose-induced T7 RNA polymerase-PT7 promoter system was constructed to ensure the efficient expression of each key heterologous pathway in E. coli. Next, a new tryptophan hydroxylase mutant was used to construct an efficient tryptophan hydroxylation module, and the cofactor tetrahydrobiopterin synthesis and regeneration pathway was expressed in combination. The L-Trp synthesis module was constructed by modifying the key metabolic nodes of tryptophan biosynthesis, and the heterologous synthesis of 5-HTP was achieved. Finally, the NAD(P)H regeneration module was constructed by the moderate expression of the heterologous GDHesi pathway, which successfully reduced the surplus of the intermediate L-Trp. The final engineered strain HTP11 was able to produce 8.58 g/L 5-HTP in a 5-L bioreactor with a yield of 0.095 g/g glucose and a maximum real-time productivity of 0.48 g/L/h, the highest values reported by microbial fermentation. CONCLUSION: In this study, we demonstrate the successful design of a cell factory for high-level 5-HTP production, combined with simple processes that have potential for use in industrial applications in the future. Thus, this study provides a reference for the production of high-value amino acid derivatives using a systematic modular engineering strategy and a basis for an efficient engineered strain development of 5-HTP high-value derivatives.
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5-Hidroxitriptofano , Engenharia Metabólica , 5-Hidroxitriptofano/genética , 5-Hidroxitriptofano/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Glucose/metabolismo , NAD/metabolismo , Neurotransmissores/metabolismo , Serotonina/metabolismo , Triptofano/metabolismo , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo , Xilose/metabolismoRESUMO
Drag reduction is a key problem in marine vehicles and fluid transportation industries. Reducing drag strategies and mechanisms need to be further investigated. To explore a bionic approach for reducing flow resistance, experimental and numerical simulation research was conducted to study the drag reduction characteristics of the Paramisgurnus dabryanus surface microstructure. In this study, the large-area flexible surface of the bionic loach scale was prepared by the template method of one-step demoulding. The water tunnel experiment results show that compared with the smooth surface, the drag reduction rate of the bionic surface ranges from 9.42% to 17.25%. And the numerical simulation results indicate that the pressure gradient and low-speed vortex effect created by the bionic loach scales can effectively reduce the friction drag. The results of experimental data and numerical simulation both prove that the bionic scales of Paramisgurnus dabryanus can achieve the underwater drag reduction function. This research provides a reference for drag reduction in marine industries and fluid delivery applications.
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The treatment of diabetes lies in developing novel functional carriers, which are expected to have the unique capability of monitoring blood glucose levels continuously and dispensing insulin correctly and timely. Hence, this study is proposing to create a smart self-regulated insulin delivery system according to changes in glucose concentration. Temperature and glucose dual responsive copolymer microcapsules bearing N-isopropylacrylamide and 3-acrylamidophenylboronic acid as main components were developed by bottom-spray coating technology and template method. The insulinoma ß-TC6 cells were trapped in the copolymer microcapsules by use of temperature sensitivity, and then growth, proliferation, and glucose-responsive insulin secretion of microencapsulated cells were successively monitored. The copolymer microcapsules showed favorable structural stability and good biocompatibility against ß-TC6 cells. Compared with free cells, the biomicrocapsules presented a more effective and safer glucose-dependent insulin release behavior. The bioactivity of secreted and released insulin did not differ between free and encapsulated ß-TC6 cells. The results demonstrated that the copolymer microcapsules had a positive effect on real-time sensing of glucose and precise controlled release of insulin. The intelligent drug delivery system is supposed to mimic insulin secretion in a physiological manner, and further provide new perspectives and technical support for the development of artificial pancreas.
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InsulinaRESUMO
OBJECTIVE: To explore the effects of hypoxic preconditioning neural stem cell (P-NSC) transplantation on rats with spinal cord injury (SCI). METHODS: After identification, the NSCs were treated with hypoxic preconditioning. The NSCs migration was detected by Transwell method. RT-qPCR was used to detect the mRNA levels of HIF-1α, CXCR4 in NSC. The secretion of representative neurotrophic factors (VEGF, HGF, and BDNF) was checked by Western blot. Forty-six SCI rats were randomly divided into three experimental groups: SCI group (PBS injection, n = 10); N-NSC group (NSC atmospheric normoxic pretreatment injection, n = 18); and P-NSC group (NSC 's hypoxic preconditioning injection, n = 18). The sham operation group was also included (rats underwent laminectomy but not SCI, n = 10). The recovery of hindlimb motor function was evaluated by BBB score. The level of spinal cord inflammation (IL-1ß, TNF-α, and IL-6) was determined by ELISA. Western blot was used to detect the content of TMIGD1 and TMIGD3 in spinal cord. RESULTS: Compared with the N-NSC group, the number of NSC-passing membranes in the P-NSC group increased with the increase of the culture time (p < 0.05). Compared with N-NSC, P-NSC had higher levels of VEGF, HGF, and BDNF after 1 week of culture (p < 0.05). The BBB score of the P-NSC group was significantly higher than that of the N-NSC group at 7 and 28 days (p < 0.05). Compared with the SCI group, the levels of TNF-α, IL-1ß, and IL-6 were significantly reduced after NSC treatment, and the P-NSC group was lower than the N-NSC group (p < 0.05). Compared with the SCI group, the levels of TMIGD1 and TMIGD3 increased. Compared with the N-NSC group, and the levels of TMIGD1 and TMIGD3 increased in the P-NSC group (p < 0.05). CONCLUSION: P-NSC administration could improve SCI injury, and the levels of TMIGD1 and TMIGD3.
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Membrana Celular/metabolismo , Movimento Celular/efeitos dos fármacos , Domínios de Imunoglobulina , Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/cirurgia , Transplante de Células-Tronco/métodos , Animais , Hipóxia , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Using the unique Survey of Foreigner Residents in China from 2018 to 2019, this study examines the assimilation of international migrants in China by considering how migrants' intention to assimilate and perceptions of local control affect their behavior, which in turn affects their assimilation outcomes. The main behavior upon which we focus on is the formation of a host social network. Regression analyses and formal mediation analyses are performed to explore how intention and perceived control serve as motivators or barriers that facilitate or restrict international migrants' acculturation and structural assimilation via host social network formation or other behaviors. Our results show that migrants' intention to assimilate has significant effects on their acculturation and structural assimilation outcomes via the establishment of a host social network and via other behaviors. As a result, it has a strong total impact on migrants' assimilation outcomes, as tested with a formal Sobel test. Migrants' perceptions of local control, in contrast, have negative direct effects on both acculturation and structural assimilation, but no significant indirect effects are identified, which suggests that perceived local control may not affect migrants' formation of a host social network but may influence other behaviors. From the Sobel test, we find no evidence of total effects from the perceptions of local control. Supplementary Information: The online version contains supplementary material available at 10.1007/s12134-021-00925-y.
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Glioblastoma is the most common primary intracranial malignant tumor in adults and has high morbidity and high mortality. TMEM158 has been reported to promote the progression of solid tumors. However, its potential role in glioma is still unclear. Here, we found that TMEM158 expression in human glioma cells in the tumor core was significantly higher than that in noncancerous cells at the tumor edge using bioinformatics analysis. Cancer cells in patients with primary GBMs harbored significantly higher expression of TMEM158 than those in patients with WHO grade II or III gliomas. Interestingly, regardless of tumor grading, human glioma samples that were IDH1-wild-type (IDH1-WT) exhibited higher expression of TMEM158 than those with IDH1-mutant (IDH1-Mut). We also illustrated that TMEM158 mRNA expression was correlated with poor overall survival in glioma patients. Furthermore, we demonstrated that silencing TMEM158 inhibited the proliferation of glioma cells and that TMEM158 overexpression promoted the migration and invasion of glioma cells by stimulating the EMT process. We found that the underlying mechanism involves STAT3 activation mediating TMEM158-driven glioma progression. In vivo results further confirmed the inhibitory effect of the TMEM158 downregulation on glioma growth. Collectively, these findings further our understanding of the oncogenic function of TMEM158 in gliomas, which represents a potential therapeutic target, especially for GBMs.