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1.
BMC Anesthesiol ; 23(1): 233, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37434138

RESUMEN

BACKGROUND: This investigation aimed to evaluate the impact of continuous pericapsular nerve group (PENG) block and continuous fascia iliac compartment block (FICB) on postoperative pain following total hip arthroplasty (THA). METHODS: This prospective, randomized, and controlled trial recruited a cohort of fifty-seven patients with unilateral femoral neck fractures from Xi'an Aerospace General Hospital in northwest China between July 2020 and November 2021. These patients were randomly assigned to two groups: the continuous PENG block group (PENG group, n = 29) and the continuous FICB group (FICB group, n = 28). Under ultrasound guidance, PENG block and FICB procedures were performed prior to spinal anesthesia, utilizing 20 ml of 0.25% ropivacaine for PENG block and 30 ml of 0.25% ropivacaine for FICB. Subsequently, a catheter was inserted. All study participants received a standardized postoperative multimodal analgesic regimen, including intravenous administration of 30 mg Ketorolac tromethamine every eight hours and patient-controlled neural analgesia (PCNA) after surgery. Numerical rating scale (NRS) scores at rest and during exercise were recorded at various time points: prior to block (T0), 30 min post-blockade (T1), and 6 h (T2), 12 h (T3), 24 h (T4), and 48 h (T5) postoperatively. Additional data collected encompassed postoperative quadriceps muscle strength, the time of initial ambulation after surgery, the number of effective PCNA activations, rescue analgesia requirements, and occurrences of adverse events (such as nausea and vomiting, hematoma, infection, catheter detachment, or displacement) within 48 h following surgery. RESULTS: In the PENG group, the resting NRS pain scores exhibited lower values at T1, T4, and T5 than those at T0. Furthermore, exercise NRS pain scores at T1-T5 were lower in the PENG group than in the FICB group. Similarly, during the same postoperative period, the PENG group demonstrated enhanced quadriceps strength on the affected side compared to the FICB group. Additionally, the PENG group displayed earlier postoperative ambulation and reduced occurrences of effective PCNA activations and rescue analgesia requirements compared to the FICB group. CONCLUSION: Continuous PENG block exhibited superior analgesic efficacy after THA compared to continuous FICB, promoting recovery of quadriceps strength on the affected side and facilitating early postoperative ambulation. TRIAL REGISTRATION: This clinical trial was registered in the China Clinical Trials Center ( http://www.chictr.org.cn ) on 20/07/2020, with the registration number ChiCTR2000034821.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Músculo Cuádriceps , Humanos , Manejo del Dolor , Artroplastia de Reemplazo de Cadera/efectos adversos , Nervio Femoral , Antígeno Nuclear de Célula en Proliferación , Estudios Prospectivos , Ropivacaína , Fascia , Analgesia Controlada por el Paciente , Dolor
2.
Sensors (Basel) ; 19(23)2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31805667

RESUMEN

Modern railway track health monitoring requires high accuracy measurements to ensure comfort and safety. Although Global Navigation Satellite System/Inertial Navigation System (GNSS/INS) integration has been extended to track geometry measurements to improve the work efficiency, it has been questioned due to its positioning accuracy at the centimeter or millimeter level. We propose the relative spatial accuracy based on the accuracy requirement of track health monitoring. A requirement assessment of the spatial relative accuracy is conducted for shortwave track irregularity measurements based on evaluation indicators and relative accuracy calculations. The threshold values of the relative spatial accuracy that satisfy the constraints of shortwave track irregularity measurements are derived. Motion-constrained GNSS/INS integration is performed to improve the navigation accuracy considering the dynamic characteristics of the track geometry measurement trolley. The results of field tests show that the mean square error and the Allan deviation of the relative position errors of motion-constrained GNSS/INS integration are smaller than 0.67 mm and 0.16 mm, respectively, which indicates that this approach meets the accuracy requirements of shortwave track irregularities, especially vertical irregularities. This work can provide support for the application of GNSS/INS systems in track irregularity measurement.


Asunto(s)
Sistemas de Información Geográfica , Humanos , Movimiento (Física) , Ondas de Radio , Comunicaciones por Satélite
3.
Sensors (Basel) ; 19(16)2019 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-31405160

RESUMEN

Global Navigation Satellite System pseudorange biases are of great importance for precise positioning, timing and ionospheric modeling. The existence of BeiDou Navigation Satellite System (BDS) receiver-related pseudorange biases will lead to the loss of precision in the BDS satellite clock, differential code bias estimation, and other precise applications, especially when inhomogeneous receivers are used. In order to improve the performance of BDS precise applications, two ionosphere-free and geometry-free combinations and ionosphere-free pseudorange residuals are proposed to calibrate the raw receiver-related pseudorange biases of BDS on each frequency. Then, the BDS triple-frequency receiver-related pseudorange biases of seven different manufacturers and twelve receiver models are calibrated. Finally, the effects of receiver-related pseudorange bias are analyzed by BDS single-frequency single point positioning (SPP), single- and dual-frequency precise point positioning (PPP), wide-lane uncalibrated phase delay (UPD) estimation, and ambiguity resolution, respectively. The results show that the BDS SPP performance can be significantly improved by correcting the receiver-related pseudorange biases and the accuracy improvement is about 20% on average. Moreover, the accuracy of single- and dual-frequency PPP is improved mainly due to a faster convergence when the receiver-related pseudorange biases are corrected. On the other hand, the consistency of wide-lane UPD among different stations is improved significantly and the standard deviation of wide-lane UPD residuals is decreased from 0.195 to 0.061 cycles. The average success rate of wide-lane ambiguity resolution is improved about 42.10%.

4.
Sensors (Basel) ; 18(12)2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30513593

RESUMEN

The BeiDou system satellites may be unhealthy due to many reasons, affecting system performance in different ways. Therefore, it is important to analyze the causes and characteristics of the satellites' unhealthy states. In this study, these states are classified into five types based on the broadcast ephemeris. Three criteria are presented, based on which a general classification method is proposed. Data from July 2017 to June 2018 are analyzed to validate the method, from which we know that the average unhealthy duration due to satellite maneuvers is much longer than the duration of unhealthy states related to satellite orbit or clock anomalies, and the other unhealthy states may be caused by inbound or outbound satellites. Statistics show that most of the time, the number of unhealthy satellites is no more than two and the average positioning accuracy in the service area will decrease by no more than 0.75 and 1.2 meters when one or two BDS satellites are unhealthy, respectively.

5.
J Acoust Soc Am ; 140(5): 3643, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27908058

RESUMEN

The parametric array loudspeaker (PAL) is an application of the parametric acoustic array in air, which can be applied to transmit a narrow audio beam from an ultrasonic emitter. However, nonlinear distortion is very perceptible in the audio beam. Modulation methods to reduce the nonlinear distortion are available for on-axis far-field applications. For other applications, preprocessing techniques are wanting. In order to develop a preprocessing technique with general applicability to a wide range of operating conditions, the Volterra filter is investigated as a nonlinear model of the PAL in this paper. Limitations of the standard audio-to-audio Volterra filter are elaborated. An improved ultrasound-to-ultrasound Volterra filter is proposed and empirically demonstrated to be a more generic Volterra model of the PAL.

6.
J Acoust Soc Am ; 137(2): 777-84, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25698012

RESUMEN

This paper describes a method to compute the far-field directivity of a parametric loudspeaker array (PLA), whereby the steerable parametric loudspeaker can be implemented when phased array techniques are applied. The convolution of the product directivity and the Westervelt's directivity is suggested, substituting for the past practice of using the product directivity only. Computed directivity of a PLA using the proposed convolution model achieves significant improvement in agreement to measured directivity at a negligible computational cost.


Asunto(s)
Acústica/instrumentación , Amplificadores Electrónicos , Simulación por Computador , Modelos Teóricos , Sonido , Transductores de Presión , Diseño de Equipo , Movimiento (Física) , Presión , Factores de Tiempo
7.
Sensors (Basel) ; 15(10): 25399-415, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26437415

RESUMEN

In order to track the carrier phases of Global Navigation Satellite Systems (GNSS) signals in signal degraded environments, a dual antenna joint carrier tracking loop is proposed and evaluated. This proposed tracking loop processes inputs from two antennas, namely the master antenna and the slave antenna. The master antenna captures signals in open-sky environments, while the slave antenna capture signals in degraded environments. In this architecture, a Phase Lock Loop (PLL) is adopted as a master loop to track the carrier phase of the open-sky signals. The Doppler frequency estimated by this master loop is utilized to assist weak carrier tracking in the slave loop. As both antennas experience similar signal dynamics due to satellite motion and clock frequency variations, a much narrower loop bandwidth and possibly a longer coherent integration can be adopted to track the weak signals in slave channels, by utilizing the Doppler aid from master channels. PLL tracking performance is affected by the satellite/user dynamics, clock instability, and thermal noise. In this paper, their impacts on the proposed phase tracking loop are analyzed and verified by both simulation and field data. Theoretical analysis and experimental results show that the proposed loop structure can track degraded signals (i.e., 18 dB-Hz) with a very narrow loop bandwidth (i.e., 0.5 Hz) and a TCXO clock.

8.
Sensors (Basel) ; 15(12): 30104-14, 2015 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-26633414

RESUMEN

In order to improve the precision of GLONASS orbits, this paper presents a method to connect the data segments of a single station-satellite pair to increase the observation continuity and, consequently, the strength of the precise orbit determination (POD) solution. In this method, for each GLONASS station-satellite pair, the wide-lane ambiguities derived from the Melbourne-Wübbena combination are statistically tested and corrected for phase integer offsets and then the same is carried out for the narrow-lane ambiguities calculated from the POD solution. An experimental validation was carried out using one-month GNSS data of a global network with 175 IGS stations. The result shows that, on average, 27.1% of the GLONASS station-satellite pairs with multiple data segments could be connected to a single long observation arc and, thus, only one ambiguity parameter was estimated. Using the connected data, the GLONASS orbit overlapping RMS at the day boundaries could be reduced by 19.2% in ideal cases with an averaged reduction of about 6.3%.

9.
Sensors (Basel) ; 15(1): 733-59, 2015 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-25569751

RESUMEN

A GNSS/INS deeply-coupled system can improve the satellite signals tracking performance by INS aiding tracking loops under dynamics. However, there was no literature available on the complete modeling of the INS branch in the INS-aided tracking loop, which caused the lack of a theoretical tool to guide the selections of inertial sensors, parameter optimization and quantitative analysis of INS-aided PLLs. This paper makes an effort on the INS branch in modeling and parameter optimization of phase-locked loops (PLLs) based on the scalar-based GNSS/INS deeply-coupled system. It establishes the transfer function between all known error sources and the PLL tracking error, which can be used to quantitatively evaluate the candidate inertial measurement unit (IMU) affecting the carrier phase tracking error. Based on that, a steady-state error model is proposed to design INS-aided PLLs and to analyze their tracking performance. Based on the modeling and error analysis, an integrated deeply-coupled hardware prototype is developed, with the optimization of the aiding information. Finally, the performance of the INS-aided PLLs designed based on the proposed steady-state error model is evaluated through the simulation and road tests of the hardware prototype.

10.
Sensors (Basel) ; 15(7): 16710-28, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-26184206

RESUMEN

A new scan that matches an aided Inertial Navigation System (INS) with a low-cost LiDAR is proposed as an alternative to GNSS-based navigation systems in GNSS-degraded or -denied environments such as indoor areas, dense forests, or urban canyons. In these areas, INS-based Dead Reckoning (DR) and Simultaneous Localization and Mapping (SLAM) technologies are normally used to estimate positions as separate tools. However, there are critical implementation problems with each standalone system. The drift errors of velocity, position, and heading angles in an INS will accumulate over time, and on-line calibration is a must for sustaining positioning accuracy. SLAM performance is poor in featureless environments where the matching errors can significantly increase. Each standalone positioning method cannot offer a sustainable navigation solution with acceptable accuracy. This paper integrates two complementary technologies-INS and LiDAR SLAM-into one navigation frame with a loosely coupled Extended Kalman Filter (EKF) to use the advantages and overcome the drawbacks of each system to establish a stable long-term navigation process. Static and dynamic field tests were carried out with a self-developed Unmanned Ground Vehicle (UGV) platform-NAVIS. The results prove that the proposed approach can provide positioning accuracy at the centimetre level for long-term operations, even in a featureless indoor environment.

11.
Sensors (Basel) ; 14(1): 1249-66, 2014 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-24434880

RESUMEN

Modern observation technology has verified that measurement errors can be proportional to the true values of measurements such as GPS, VLBI baselines and LiDAR. Observational models of this type are called multiplicative error models. This paper is to extend the work of Xu and Shimada published in 2000 on multiplicative error models to analytical error analysis of quantities of practical interest and estimates of the variance of unit weight. We analytically derive the variance-covariance matrices of the three least squares (LS) adjustments, the adjusted measurements and the corrections of measurements in multiplicative error models. For quality evaluation, we construct five estimators for the variance of unit weight in association of the three LS adjustment methods. Although LiDAR measurements are contaminated with multiplicative random errors, LiDAR-based digital elevation models (DEM) have been constructed as if they were of additive random errors. We will simulate a model landslide, which is assumed to be surveyed with LiDAR, and investigate the effect of LiDAR-type multiplicative error measurements on DEM construction and its effect on the estimate of landslide mass volume from the constructed DEM.

12.
Chem Commun (Camb) ; 60(78): 10902-10905, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39254044

RESUMEN

Two-dimensional Cs2Pb(SCN)2I2 perovskite has an ultra-small interlayer spacing, inducing a series of interesting semiconductor properties, such as efficient interlayer carrier transport as well as lower exciton binding energy compared to perovskites with long alkylammonium cations. The prepared Cs2Pb(SCN)2I2 photodetector achieves a high on/off ratio of 2.1 × 104 with a specific detectivity of 6.2 × 1011 jones to 450 nm visible light, and a high sensitivity of 2747 µC Gyair-1 cm-2 to X-rays.

13.
Nat Commun ; 15(1): 1766, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409083

RESUMEN

The proper axial length of the eye is crucial for achieving emmetropia. In this study, we present a wireless battery-free eye modulation patch designed to correct high myopia and prevent relapse. The patch consists of piezoelectric transducers, an electrochemical micro-actuator, a drug microneedle array, µ-LEDs, a flexible circuit, and biocompatible encapsulation. The system can be wirelessly powered and controlled using external ultrasound. The electrochemical micro-actuator plays a key role in precisely shortening the axial length by driving the posterior sclera inward. This ensures accurate scene imaging on the retina for myopia eye. The drug microneedle array delivers riboflavin to the posterior sclera, and µ-LEDs' blue light induces collagen cross-linking, reinforcing sclera strength. In vivo experiments demonstrate that the patch successfully reduces the rabbit eye's axial length by ~1217 µm and increases sclera strength by 387%. The system operates effectively within the body without the need for batteries. Here, we show that the patch offers a promising avenue for clinically treating high myopia.


Asunto(s)
Miopía , Animales , Conejos , Reactivos de Enlaces Cruzados/farmacología , Modelos Animales de Enfermedad , Miopía/terapia , Esclerótica , Riboflavina
14.
Int J Biol Macromol ; 269(Pt 1): 132015, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38697432

RESUMEN

This study aimed to compare the effects of pectin and hydrolyzed pectin coating as pre-frying treatments on acrylamide content and quality characteristics of fried potato chips. The hydrolyzed pectin with molecular weight (Mw) of 8.81 ± 0.49 kDa was obtained through partial degradation of pectin (Mw: 747.57 ± 6.73 kDa) using pectinase. Results showed that both pectin and hydrolyzed pectin coating significantly inhibited acrylamide formation and inhibition rates exceeded 90 %. Hydrolyzed pectin had stronger inhibitory activity against acrylamide formation than pectin, especially when the concentration of hydrolyzed pectin was >2 %, its inhibitory rate exceeded 95 %. Compared to pectin coating, hydrolyzed pectin coating endow fried potato chips with smaller browning, higher crispness, less moisture but higher oil content. Overall, hydrolyzed pectin had better application prospects than pectin in inhibiting acrylamide formation of fried potato chips.


Asunto(s)
Acrilamida , Pectinas , Solanum tuberosum , Solanum tuberosum/química , Pectinas/química , Acrilamida/química , Hidrólisis , Culinaria , Peso Molecular
15.
Sci Rep ; 13(1): 18057, 2023 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872211

RESUMEN

Uterine corpus endometrial carcinoma (UCEC) is infiltrated by immune cells, which are involved in the growth and proliferation of malignant tumors and resistance to immunotherapy. This study suggested that RNA modification regulators played an important role in the development and prognosis of UCEC. Many studies confirmed that RNA modification played an essential role in tumor immune regulation, and abnormal RNA modification contributed to tumorigenesis and cancer progression. Based on the RNA modification regulatory factors, the UCEC samples from TCGA (The Cancer Genome Atlas) were classified into two clusters, namely Cluster A and Cluster B, using unsupervised consensus clustering. We obtained DEG (differentially expressed genes) between the two clusters, and constructed a risk model of RNA modification-related genes using DEGs. Cluster A had lower RNA modification regulatory factors, richer immune cell infiltration, and better prognosis. The differentially expressed genes between the two clusters were obtained, and these genes were used for modeling. This model divided patients with UCEC into two groups. The low-risk group had better immune infiltration, and the ROC (receiver operating characteristic) curve showed that this model had good predictive efficacy. The low-risk group had a better response to immunotherapy by immune checkpoint prediction. We obtained the key gene L-dopa decarboxylase (DDC) through the intersection of LASSO model genes and GEO dataset GSE17025. We evaluated the potential biological functions of DDC. The differences in the expression of DDC were verified by immunohistochemistry. We evaluated the relationship between DDC and immune cell infiltration and verified this difference using immunofluorescence. Cluster A with low expression of RNA modification regulators has better prognosis and richer immune cell infiltration, therefore, we believed that RNA modification regulators in UCEC were closely related to the tumor microenvironment. Also, the risk score could well predict the prognosis of patients and guide immunotherapy, which might benefit patients with UCEC.


Asunto(s)
Carcinoma Endometrioide , Neoplasias Endometriales , Humanos , Femenino , Microambiente Tumoral/genética , Neoplasias Endometriales/genética , Pronóstico , ARN , Descarboxilasas de Aminoácido-L-Aromático
16.
Food Chem Toxicol ; 181: 114103, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37852353

RESUMEN

There are several technical challenges and public issues concerning genome editing applications before they become viable in commercial aquaculture. Recently, we developed a novel strategy to generate all-female (AF) common carp, which exhibited a growth advantage over the control carp, using genetic editing through single gene-targeting manipulation. Here, we found that the body weight of the AF common carp was higher by 22.58% than that of the control common carp. Because the genotype of the AF common carp was cyp17a1+/-;XX, the contents of sex steroids were normally synthesized, as they were comparable to that of the control female carp. To evaluate the food safety of the AF carp, Wistar rats were fed a diet containing control female carp (control, C) or all-female (AF) carp at an incorporation rate of 5, 10 and 20% (w/w) for 90 days. Compared with those fed control carp, the rats fed AF common carp exhibited no significant difference in body weight, food intake, feed conversion ratio, hematology, serum biochemistry, urine test, relative organ weight, gross necropsy, and histopathological examination. This is the first food safety assessment of the farmed fish strain cultured using CRISPR/Cas9, which will further advance the fishery development of genome-edited animals.


Asunto(s)
Carpas , Edición Génica , Femenino , Animales , Ratas , Ratas Wistar , Genotipo , Peso Corporal , Alimentación Animal/análisis , Dieta
17.
J Acoust Soc Am ; 131(3): 1938-45, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22423691

RESUMEN

In a recent work, the beamsteering characteristics of parametric loudspeakers were validated in an experiment. It was shown that based on the product directivity model, the locations and amplitudes of the mainlobe and grating lobes could be predicted within acceptable errors. However, the measured amplitudes of sidelobes have not been able to match the theoretical results accurately. In this paper, the original theories behind the product directivity model are revisited, and three modified product directivity models are proposed: (i) the advanced product directivity model, (ii) the exponential product directivity model, and (iii) the combined product directivity model. The proposed product directivity models take the radii of equivalent Gaussian sources into account and obtain better predictions of sidelobes for the difference frequency waves. From the comparison between measurement results and numerical solutions, all the proposed models outperform the original product directivity model in terms of selected sidelobe predictions by about 10 dB.

18.
Materials (Basel) ; 15(1)2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35009451

RESUMEN

Composite thin-walled booms can easily be folded and self-deployed by releasing stored strain energy. Thus, such booms can be used to deploy antennas, solar sails, and optical telescopes. In the present work, a new four-cell lenticular honeycomb deployable (FLHD) boom is proposed, and the relevant parameters are optimized. Coiling dynamics analysis of the FLHD boom under a pure bending load is performed using nonlinear explicit dynamics analysis, and the coiling simulation is divided into three consecutive steps, namely, the flattening step, the holding step, and the hub coiling step. An optimal design method for the coiling of the FLHD boom is developed based on a back propagation neural network (BPNN). A full factorial design of the experimental method is applied to create 36 sample points, and surrogate models of the coiling peak moment (Mpeak) and maximum principal stress (Smax) are established using the BPNN. Fatigue cracks caused by stress concentration are avoided by setting Smax to a specific constraint and the wrapping Mpeak and mass of the FLHD boom as objectives. Non-dominated sorting genetic algorithm-II is used for optimization via ISIGHT software.

19.
Front Endocrinol (Lausanne) ; 13: 923475, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35937837

RESUMEN

Human-directed domestication of terrestrial animals traditionally requires thousands of years for breeding. The most prominent behavioral features of domesticated animals include reduced aggression and enhanced tameness relative to their wild forebears, and such behaviors improve the social tolerance of domestic animals toward both humans and crowds of their own species. These behavioral responses are primarily mediated by the hypothalamic-pituitary-adrenal (inter-renal in fish) (HPA/I) endocrine axis, which is involved in the rapid conversion of neuronal-derived perceptual information into hormonal signals. Over recent decades, growing evidence implicating the attenuation of the HPA/I axis during the domestication of animals have been identified through comprehensive genomic analyses of the paleogenomic datasets of wild progenitors and their domestic congeners. Compared with that of terrestrial animals, domestication of most farmed fish species remains at early stages. The present review focuses on the application of HPI signaling attenuation to accelerate the domestication and genetic breeding of farmed fish. We anticipate that deeper understanding of HPI signaling and its implementation in the domestication of farmed fish will benefit genetic breeding to meet the global demands of the aquaculture industry.


Asunto(s)
Domesticación , Sistema Hipófiso-Suprarrenal , Animales , Genómica , Humanos , Sistema Hipotálamo-Hipofisario , Hipotálamo
20.
Front Endocrinol (Lausanne) ; 13: 879962, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35966057

RESUMEN

Insulin-like growth factor 1 (IGF1) is an essential effector of the growth hormone (GH)/IGF1 axis for somatic growth regulation in mammals. However, its functions have not been thoroughly investigated in zebrafish in vivo. In this study, the igf1-deficient zebrafish model was developed using the CRISPR/Cas9 technique. In this study all the results were performed on both male and female animals. The growth of both male and female igf1-deficient zebrafish were reduced. The igf1 deficiency leads to significant complementary up-regulation of transcriptional expression levels of insulin, igf2 and igf3. This suggested that igf2 and igf3 may act with redundant functions. While the upregulation of gh1 expression can only be detected in igf1-deficient females. At the same time, significant growth retardation, fatty liver, reduced activated levels of ribosomal S6 (S6) are seen only in igf1-deficient males. On the other hand, significant hyperglycemia, elevated transcriptional expression levels of phosphenolpyruvate carboxykinase (pepck) and levels of phosphorylated extracellular signal-regulated kinase (ERK1/2), with additional reduced hepatic lactate/pyruvate (L/P) ratios can only observed in igf1-deficient females. Impaired glucose uptake has been recorded in the primary cultured hepatocytes from igf1-deficient females, but not males. Intriguingly, exposure to 17beta-estroadiol (E2) can partially ameliorated the defects of fatty liver and activation of AKT/mTOR signaling in igf1-deficient males. Our studies demonstrate the significant functions of IGF1 on somatic regulation in zebrafish, with asymmetric gender-related consequences. Our data thus suggest that the zebrafish IGF1 is preferentially required for the activation of AKT/mTOR signaling in male zebrafish, but glucose uptake in females.


Asunto(s)
Hígado Graso , Factor I del Crecimiento Similar a la Insulina , Animales , Hígado Graso/metabolismo , Femenino , Glucosa , Trastornos del Crecimiento , Pérdida Auditiva Sensorineural , Factor I del Crecimiento Similar a la Insulina/deficiencia , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Mamíferos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/genética , Pez Cebra/genética
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