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1.
Opt Lett ; 49(19): 5427-5430, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352973

RESUMO

Fast steering mirrors (FSMs) offer a potential alternative for large-range deflection of light beams. However, for a large-stroke FSM, its pointing precision is unacceptably deteriorated due to the actuator non-uniformity, mechanical axis coupling, and the coupling of line-of-sight (LOS) kinematics. This Letter proposes a comprehensive beam-pointing algorithm by decoupling the LOS kinematic model and establishing a two-dimensional correction mapping to compensate for the non-uniformity and mechanical coupling. Moreover, the incident angle is calibrated by a non-contact method to construct the LOS kinematic model accurately. The experimental results proved that the beam-pointing accuracy can achieve a sub-milliradian level within the square field of regard (FOR) of ±25° horizontally and ±14° vertically. A pointing error of 0.87 mrad can be guaranteed within the horizontal range of -30° to 36° and the vertical range of ±24°. Therefore, the proposed method can achieve high-precision beam pointing in a large FOR and contributes to the miniaturization of optical systems.

2.
Biochim Biophys Acta Mol Basis Dis ; 1870(8): 167496, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39237046

RESUMO

Liver ischemia-reperfusion (I/R) injury is a detrimental complication of organ transplantation, shock, and sepsis. However, the available drugs to mitigate I/R injury remain limited. Jujuboside A (JuA) is renowned for its antioxidant, anti-inflammatory, and anti-apoptotic properties; nevertheless, its potential in liver I/R injury remains unknown. Thus, this study aimed to explore the role and underlying mechanisms of JuA in liver I/R injury. Mouse models of I/R and AML12 cell models of hypoxia/reoxygenation (H/R) were constructed. Haematoxylin and eosin staining, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) detection, and cell viability analysis were used to assess liver injury. To evaluate oxidative stress, inflammation, apoptosis, and mitochondrial damage, immunofluorescence staining, transmission electron microscopy analysis, enzyme-linked immunosorbent assay, and flow cytometry were conducted. Moreover, molecular docking techniques and western blot were employed to identify downstream target molecules and pathways affected by JuA. The results showed that JuA pretreatment effectively attenuated liver necrosis and ALT and AST level elevations induced by I/R while enhancing AML12 cell viability following H/R. Furthermore, JuA pretreatment suppressed oxidative stress triggered by I/R and H/R, thereby inhibiting the level of pro-inflammatory factors and NLRP3 inflammasome activation. Notably, JuA pretreatment alleviated mitochondrial damage and apoptosis. Mechanistically, JuA pretreatment resulted in the activation of the AKT/NRF2/HO-1 signalling pathways, whereas MK2206, the inhibitor of AKT, partially reversed the hepatoprotective effects of JuA during liver I/R. Collectively, our findings illustrated that JuA mitigated oxidative stress, inflammation, apoptosis, and mitochondrial damage by facilitating the AKT/NRF2/HO-1 signalling pathway, thereby alleviating liver I/R injury.


Assuntos
Apoptose , Fígado , Fator 2 Relacionado a NF-E2 , Proteínas Proto-Oncogênicas c-akt , Traumatismo por Reperfusão , Transdução de Sinais , Animais , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Masculino , Fígado/patologia , Fígado/metabolismo , Fígado/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Heme Oxigenase-1/metabolismo , Linhagem Celular , Proteínas de Membrana/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo
3.
Sci Rep ; 14(1): 20304, 2024 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-39218910

RESUMO

Dysnatremia is common in donors and recipients of liver transplantation (LT). However, the influence of dysnatremia on LT prognosis remains controversial. This study aimed to investigate effects of donors' and recipients' serum sodium on LT prognosis. We retrospectively reviewed 248 recipients who underwent orthotopic LT at our center between January 2016 and December 2018. Donors and recipients perioperative and 3-year postoperative clinical data were included. Delta serum sodium was defined as the donors' serum sodium minus the paired recipients' serum sodium. Donors with serum sodium > 145 mmol/L had significantly higher preoperative blood urea nitrogen (BUN) (P < 0.01) and creatinine (Cr) (P < 0.01) than others. Preoperative total bilirubin (TBIL) (P < 0.01), direct bilirubin (DBIL) (P < 0.01), BUN (P < 0.01), Cr (P < 0.01) were significantly higher in the hyponatremia group of recipients than the other groups, but both of donors' and recipients' serum sodium had no effect on the LT prognosis. In the delta serum sodium < 0 mmol/L group, TBIL (P < 0.01) and DBIL (P < 0.01) were significantly higher in postoperative 1 week than the other groups, but delta serum sodium had no effect on the postoperative survival rates. Dysnatremia in donors and recipients of LT have no effect on postoperative survival rates, hepatic and renal function, but recipients with higher serum sodium than donors have significantly higher TBIL and DBIL at 1 week postoperatively.


Assuntos
Transplante de Fígado , Sódio , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Feminino , Sódio/sangue , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Adulto , Doadores de Tecidos , Hiponatremia/sangue , Nitrogênio da Ureia Sanguínea , Transplantados , Bilirrubina/sangue , Período Pré-Operatório , Idoso , Creatinina/sangue
4.
Health Qual Life Outcomes ; 22(1): 59, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075537

RESUMO

OBJECTIVE: To evaluate and compare the measurement properties and consistency between the Chinese versions of EQ-5D-3L and EQ-5D-Y-3L among Chinese adolescent populations aged 15-17 years. METHODS: Chinese adolescents aged 15-17 studying in high school were recruited through online survey. Social-demographic characteristics and self-reported EQ-5D-3L and EQ-5D-Y-3L responses were collected in the survey. The consistency of responses between the two measures was assessed using redistribution property, and the consistency of utility values was assessed by intraclass correlation coefficients (ICC). Convergent validity and known-group validity were examined using Spearman's rank correlation, F-test and effect sizes, respectively. Sensitivity was compared using relative efficiency (RE). RESULTS: 762 respondents (48.8% male; age 15-17 years;) were recruited. The EQ-5D-3L showed a more severe ceiling effect than EQ-5D-Y-3L (78.2% vs. 66.0%). Respondents reported higher proportions of having problems in four dimensions using the EQ-5D-Y-3L than using the EQ-5D-3L. The consistency of corresponding dimensions between the two measures was relatively good, while non-negligible proportions of inconsistency were observed in "pain/discomfort" (11.4%) and "anxiety/depression" (15.7%) dimensions. The ICC of the utility values between the EQ-5D-3L and EQ-5D-Y-3L was 0.852 (p < 0.001). The Spearman's rank correlation (range: 0.385-0.620) indicated an acceptable convergent validity between the correlative dimensions of the EQ-5D-3L and EQ-5D-Y-3L. The EQ-5D-Y-3L had a higher efficiency than the EQ-5D-3L at detecting differences across EQ VAS subgroups (ES = 1.793 for EQ-5D-3L, ES = 1.920 for EQ-5D-Y-3L). Mixed results were observed in sensitivity. CONCLUSIONS: Both the EQ-5D-3L and EQ-5D-Y-3L are demonstrated to be valid and generally consistent for measuring HRQoL among adolescents aged 15-17 years in China. Respondents reported higher proportions of having problems using the EQ-5D-Y-3L than using the EQ-5D-3L. More research is warranted to compare the discriminant validity and test-retest reliability between the two measures.


Assuntos
Psicometria , Qualidade de Vida , Humanos , Adolescente , Masculino , China , Feminino , Inquéritos e Questionários/normas , Reprodutibilidade dos Testes , Psicometria/normas , Nível de Saúde
5.
Ecol Evol ; 13(6): e10125, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37325723

RESUMO

The landscape pattern of the Black-necked Crane (Grus nigricollis) habitat in China changed at different spatial scales and long-term periods due to natural factors and human activities, and habitat reduction and fragmentation threatened the survival of Black-necked Cranes. The factors driving the habitat landscape pattern and individual population changes of Black-necked Cranes remain to be studied. In this paper, based on remote sensing data of land use from 1980 to 2020, the changes in landscape pattern and fragmentation of the Black-necked Crane habitat in China over 40 years were analyzed from two different spatial scales using the land cover transfer matrix and landscape index. The correlation between landscape and Black-necked Crane individual population was analyzed. The most obvious observations were as follows: (1) Although transformation between landscapes occurred to varying degrees, the area of wetlands and arable land in the breeding and the wintering areas (net) increased significantly from 1980 to 2020. (2) Habitat fragmentation existed in the breeding and the wintering area and was more obvious in the wintering area. (3) The number of individuals of Black-necked Cranes increased period by period, and habitat fragmentation did not inhibit their population growth. (4) The number of individuals of Black-necked Crane was closely related to the wetland and arable land. The increasing area of wetlands and arable and the increasing landscape shape complexity all contributed to the growth of the individual population. The results also suggested that the number of individuals of Black-necked Crane was not threatened by the expanding arable land in China, and they might benefit from arable landscapes. The conservation of Black-necked Cranes should focus on the relationship between individual Black-necked Cranes and arable landscapes, and the conservation of other waterbirds should also focus on the relationship between individual waterbirds and other landscapes.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(4): 354-359, 2022 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-35527407

RESUMO

OBJECTIVES: To study the clinical features of children with colorectal polyps and the efficacy of endoscopic treatment. METHODS: A retrospective analysis was performed on the medical data of 1 351 children with colorectal polyps who were admitted and received colonoscopy and treatment in the past 8 years, including clinical features and the pattern and outcomes of endoscopic treatment. RESULTS: Among the 1 351 children, 893 (66.10%) were boys and 981 (72.61%) had an age of 2-<7 years, and hematochezia (1 307, 96.74%) was the most common clinical manifestation. Of all the children, 89.27% (1 206/1 351) had solitary polyps, and 95.77% (1 290/1 347) had juvenile polyps. The polyps were removed by electric cauterization with hot biopsy forceps (6 cases) or high-frequency electrotomy and electrocoagulation after snare ligation (1 345 cases). A total of 1 758 polyps were resected, among which 1 593 (90.61%) were pedunculated and 1 349 (76.73%) had a diameter of <2 cm. Postoperative complications included bleeding in 51 children (3.77%), vomiting in 87 children (6.44%), abdominal pain in 14 children (1.04%), and fever in 39 children (2.89%), while no perforation was observed. The children aged <3 years had the highest incidence rates of postoperative bleeding and fever (P<0.0125), and the children with a polyp diameter of ≥2 cm had significantly higher incidence rates of postoperative bleeding, vomiting, and fever (P<0.05). CONCLUSIONS: Solitary polyps, pedunculated polyps, and juvenile polyps are common types of pediatric colorectal polyps. Electric cauterization with hot biopsy forceps or high-frequency electrotomy and electrocoagulation after snare ligation can effectively remove colorectal polyps in children, with good efficacy and few complications. Younger age and larger polyp diameter are associated with a higher risk of postoperative bleeding.


Assuntos
Pólipos do Colo , Criança , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Colonoscopia , Feminino , Humanos , Pólipos Intestinais/patologia , Pólipos Intestinais/cirurgia , Masculino , Estudos Retrospectivos , Vômito
7.
Hepatology ; 76(1): 94-111, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34735734

RESUMO

BACKGROUND AND AIMS: Hepatic ischemia-reperfusion (HIR) injury, a common clinical complication of liver transplantation and resection, affects patient prognosis. Ring finger protein 5 (RNF5) is an E3 ubiquitin ligase that plays important roles in endoplasmic reticulum stress, unfolded protein reactions, and inflammatory responses; however, its role in HIR is unclear. APPROACH AND RESULTS: RNF5 expression was significantly down-regulated during HIR in mice and hepatocytes. Subsequently, RNF5 knockdown and overexpression of cell lines were subjected to hypoxia-reoxygenation challenge. Results showed that RNF5 knockdown significantly increased hepatocyte inflammation and apoptosis, whereas RNF5 overexpression had the opposite effect. Furthermore, hepatocyte-specific RNF5 knockout and transgenic mice were established and subjected to HIR, and RNF5 deficiency markedly aggravated liver damage and cell apoptosis and activated hepatic inflammatory responses, whereas hepatic RNF5 transgenic mice had the opposite effect compared with RNF5 knockout mice. Mechanistically, RNF5 interacted with phosphoglycerate mutase family member 5 (PGAM5) and mediated the degradation of PGAM5 through K48-linked ubiquitination, thereby inhibiting the activation of apoptosis-regulating kinase 1 (ASK1) and its downstream c-Jun N-terminal kinase (JNK)/p38. This eventually suppresses the inflammatory response and cell apoptosis in HIR. CONCLUSIONS: We revealed that RNF5 protected against HIR through its interaction with PGAM5 to inhibit the activation of ASK1 and the downstream JNK/p38 signaling cascade. Our findings indicate that the RNF5-PGAM5 axis may be a promising therapeutic target for HIR.


Assuntos
Proteínas de Membrana , Fosfoproteínas Fosfatases , Traumatismo por Reperfusão , Ubiquitina-Proteína Ligases , Animais , Apoptose , Humanos , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Fosfoproteínas Fosfatases/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
8.
ISA Trans ; 125: 22-30, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34167818

RESUMO

The adaptive learning and control are proposed for the full-state(FS) constrained NWMR system with external destabilization. First, the constrained state is reformulated as the unconstrained state. Then, approximating the unknown dynamics in the closed-loop (CL) system is conducted via radial basis function (RBF) NN. Also, a sliding term is designed to deal with the external destabilization and the neural network training error. The derived adaptive neural controller can realize the asymptotic stability of a robot system without violating FS constraints. Moreover, the neural weights are converged so that the unknown dynamics are expressed by the constant weights in the CL system. It is also applicable to other similar control tasks. Lastly, the proposed algorithm is simulated and validated.


Assuntos
Dinâmica não Linear , Robótica , Algoritmos , Simulação por Computador , Redes Neurais de Computação
9.
Eur J Pediatr ; 178(1): 7-16, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30446816

RESUMO

Therapy-related side effects and severe antimicrobial resistance still remain an obstacle to Helicobacter pylori eradication. This meta-analysis aimed to investigate the efficacy of Lactobacillus-supplemented triple therapy on H. pylori eradication rates and therapy-related side effects in children. Five studies involving 484 pediatric patients were included in our analysis. The pooled relative risk (RR) for eradication rates in the Lactobacillus group versus the control group was 1.19 [95% confidence interval (CI) 1.07-1.33]. In subgroup analyses based on dose and duration of Lactobacillus supplementation, the pooled RRs for eradication rates were 1.36 (95% CI 1.15-1.60) in the high-dose group, 1.08 (95% CI 0.86-1.35) in the low-dose group, 1.24 (95% CI 1.06-1.46) in the long-term group, and 1.17 (95% CI 0.96-1.44) in the short-term group. With respect to side effects, Lactobacillus supplementation significantly reduced the incidence of diarrhea (RR = 0.30, 95% CI 0.10-0.85).Conclusions: Lactobacillus, as an adjunct to triple therapy, can increase H. pylori eradication rates as well as reduce the incidence of therapy-related diarrhea in children. And a higher dose and a longer duration of supplementation may conduce to the positive impact of Lactobacillus on H. pylori eradication. What is Known: • Probiotics-supplemented triple therapy may be beneficial in improving H. pylori eradication rates and reducing therapy-related side effects in children. However, not all probiotics are beneficial to H. pylori eradication and the pooled outcomes based on different probiotics may be erroneously extrapolated to other ineffective strains. What is New: • Lactobacillus, as an adjunct to triple therapy, can increase H. pylori eradication rates as well as reduce the incidence of therapy-related diarrhea in children.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Lactobacillus , Probióticos/uso terapêutico , Adolescente , Antibacterianos/efeitos adversos , Criança , Pré-Escolar , Suplementos Nutricionais , Quimioterapia Combinada , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
10.
Food Chem ; 108(2): 542-50, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26059132

RESUMO

Microwave heating can be regarded as a possible way to produce a considerable amount of acrylamide. The present study investigated the formation of acrylamide in asparagine-glucose, asparagine-fructose and asparagine-sucrose microwave heating systems by the response surface methodology (RSM) and the orthogonal array methodology (OAM). The acrylamide content was rapidly quantified by a validated ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. Results of RSM study indicated that in the asparagine-glucose system, the acrylamide content increased in the combined condition of high temperature accompanying with short heating time (>190°C, <20min) or low temperature accompanying with long heating time (<180°C, >30min). In the asparagine-fructose system, the similar conclusion was made in the combined condition of high temperature accompanying with short heating time (>175°C, <20min) or low temperature accompanying with long heating time (<170°C, >25min). In the asparagine-sucrose system, the amount of acrylamide enhanced with the increase of both heating temperature and heating time. The fitted mathematic models were successfully applied to the quantification of acrylamide formation when the heating temperature and heating time fell into the ranges of 120-240°C and 5-35min simultaneously. OAM study showed that acrylamide is readily formed via heating binary precursors 5min at 180°C in the asparagine-glucose and asparagine-fructose systems. However, acrylamide is readily generated when the binary precursors are heated 15min at 180°C in the asparagine-sucrose system.

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