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1.
J Youth Adolesc ; 53(6): 1428-1440, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38555341

RESUMEN

Despite extensive research on the psychological impacts of digital technology, the nuanced dynamics between adolescent loneliness and problematic smartphone use, particularly across different educational levels and genders, remain underexplored. This study aims to fill this gap by employing a Random Intercept Cross-Lagged Panel Model to dissect the bidirectional relationship between loneliness and problematic smartphone use among adolescents, with a focus on the moderating roles of educational levels and gender. Engaging 3132 students from various educational institutions in China, the research conducted a three-wave longitudinal analysis across 2022-2023. The final number of participants included 1120 adolescents (53.5% female; age in 2022: M = 14.57 years, SD = 1.57). Results reveal that loneliness significantly predicts problematic smartphone use, but not vice versa, highlighting a unidirectional influence. The study uncovers crucial differences across educational levels and gender, emphasizing the stronger effect of loneliness on problematic smartphone use among junior high students and female adolescents. These findings underscore the complexity of adolescent loneliness and its relationship with digital behavior, suggesting a need for tailored interventions considering both gender and developmental stages.


Asunto(s)
Conducta del Adolescente , Soledad , Teléfono Inteligente , Humanos , Soledad/psicología , Adolescente , Femenino , Masculino , Conducta del Adolescente/psicología , Estudios Longitudinales , China , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Trastorno de Adicción a Internet/psicología , Factores Sexuales , Escolaridad
2.
Opt Lett ; 48(3): 843-846, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723603

RESUMEN

Surface plasmon excitations in metallic hole arrays have been extensively studied in the context of light-matter interaction, since the generated Bloch surface plasmon polariton (Bloch-SPP) exhibits unique properties of nanoscale light confinement, near-field enhancements, and long-range metal surface propagation. In this work, we experimentally demonstrate a plasmonic device that exhibits highly directional emission in visible light; using Ag film with a thickness of 100 nm deposited on a subwavelength porous alumina array as a plasmonic cavity, four-level rhodamine 6G (R6G) is selected as the gain material. It is suggested that a Bloch-SPP with high diffraction orders on a Ag nanohole array can generate a strong local electric field and a high Purcell factor at a nanohole edge. Moreover, directional five-fold enhanced amplified spontaneous emission (ASE) with polarization dependence is observed under a low threshold of 199.9 W/cm2 in the visible light region, which comes from the optical feedback provided by the 2D periodic nanohole array. This work opens up a wide range of applications for real-time tunable wavelength, controlled multimode laser, fluorescence detection, etc.

3.
Fish Shellfish Immunol ; 132: 108500, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36572268

RESUMEN

Ginkgo biloba leaf extract (GBE) has been extensively used in the treatment of diseases due to its anti-inflammatory, antioxidant, and immunomodulatory effects. In aquaculture, GBE is widely used as a feed additive, which is important to enhance the immunity of aquatic animals. The current study evaluated the effects of adding GBE to the diet of Penaeus vannamei (P. vannamei) under intensive aquaculture. The GBE0 (control group), GBE1, GBE2, and GBE4 groups were fed a commercial feed supplemented with 0.0, 1.0, 2.0, and 4.0 g/kg GBE for 21 days, respectively. The results showed that dietary GBE could alleviate hepatopancreas tissue damage and improve the survival rate of shrimp, and dietary 2 g/kg GBE could significantly increase the total hemocyte count (THC), the hemocyanin content, the antioxidant gene's expression, and the activity of their encoded enzymes in P. vannamei. Furthermore, transcriptome data revealed that immunity-related genes were upregulated in the GBE2 group compared with the GBE0 group after 21 days of culture. Drug metabolism-cytochrome P450, sphingolipid metabolism, linoleic acid metabolism, glycerolipid metabolism, fat digestion and protein digestion and absorption pathways were significantly enriched, according to KEGG results. Surprisingly, all of the above KEGG-enriched pathways were significantly upregulated. These findings demonstrated that supplementing P. vannamei with 2 g/kg GBE improved its environmental adaptability by improving immunity, lipid metabolism, and detoxification. In this study, a comprehensive evaluation of the effects of dietary GBE on the intensive aquaculture of P. vannamei was conducted to provide a reference for the healthy culture of P. vannamei.


Asunto(s)
Ginkgo biloba , Penaeidae , Animales , Ginkgo biloba/metabolismo , Antioxidantes/metabolismo , Extractos Vegetales , Dieta/veterinaria
4.
Clin Lab ; 69(5)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37145060

RESUMEN

BACKGROUND: The Notch signaling pathway regulates various cellular processes, including cell growth, inflammation response, and autophagy, thereby participating in the occurrence and development of various diseases. The present study aimed to investigate the molecular mechanism of Notch signaling in regulating alveolar type II epithelial cell viability and autophagy after Klebsiella pneumonia (KPN) infection. METHODS: KPN-infected human alveolar type II epithelial cells A549 (ACEII) were constructed. The autophagy inhibitor 3-methyladenine (3-MA) and Notch1 signaling inhibitor (DAPT) were used to pretreat A549 cells for 24 hours, 48 hours, and 72 hours before KPN infection. Real-time fluorescent quantitative PCR (qRT-PCR) and western blot assays were applied to detect the mRNA and protein expressions of LC3 and Notch1, respectively. ELISA was used to detect the levels of INF-γ, TNF-α, and IL-1ß in the cell supernatants. RESULTS: The results showed that KPN-infected A549 cells presented significantly upregulated Notch1 and autophagy-related protein LC3 levels, along with increased IL-1ß, TNF-α, INF-γ levels in a time-dependent manner. Autophagy inhibitor 3-methyladenine (3-MA) counteracted the promotive effects of LC3 and inflammatory cytokine levels in KPN-infected A549 cells; however, 3-MA did not influence Notch1 level. Notch1 inhibitor DAPT could suppress Notch1 and LC3 levels, thereby inhibiting inflammation response in KPN-treated A549 cells in a time-dependent way. CONCLUSIONS: KPN infection can activate the Notch signaling pathway and induce autophagy in type Ⅱ alveolar epithelial cells. Inhibiting the Notch signaling pathway may restrain KPN-induced A549 cell autophagy and inflammation response, shedding new insights for the treatment of pneumonia.


Asunto(s)
Células Epiteliales Alveolares , Neumonía , Humanos , Células Epiteliales Alveolares/metabolismo , Klebsiella pneumoniae , Factor de Necrosis Tumoral alfa/metabolismo , Neumonía/metabolismo , Inflamación/metabolismo , Autofagia
5.
J Shoulder Elbow Surg ; 32(11): 2400-2411, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37419440

RESUMEN

BACKGROUND: Obesity influences the outcomes of orthopedic surgeries such as total knee arthroplasty and spinal surgery. However, the effect of obesity on the outcomes of rotator cuff repair is unknown. This systematic review and meta-analysis aimed to examine the effect of obesity on rotator cuff repair outcomes. METHODS: PubMed, EMBASE, Web of Science, and Cochrane Library databases were searched to identify relevant studies published from their inception till July 2022. Two reviewers independently screened titles and abstracts using the specified criteria. Articles were included if they indicated the effect of obesity on rotator cuff repair and the related outcomes after surgery. Review Manager 5.4.1 software was used to perform statistical analysis. RESULTS: Thirteen articles involving 85,497 patients were included. Obese patients had higher retear rates than nonobese patients (odds ratio [OR] 2.58, 95% confidence interval [CI] 1.23-5.41, P = .01), lower American Shoulder and Elbow Surgeons scores (mean difference [MD]: -3.59, 95% CI: -5.45 to [-1.74]; P = .0001), higher visual analog scale for pain (mean difference: 0.73, 95% CI: 0.29-1.17; P = .001), higher reoperation rates (OR 1.31, 95% CI 1.21-1.42, P < .00001), and higher rates of complications (OR 1.57, 95% CI 1.31-1.87, P = .000). Obesity did not affect the duration of surgery (MD: 6.03, 95% CI: -7.63 to 19.69; P = .39) or external rotation of the shoulder (MD: -1.79, 95% CI: -5.30 to 1.72; P = .32). CONCLUSION: Obesity is a significant risk factor for retear and reoperation after rotator cuff repair. Furthermore, obesity increases the risk of postoperative complications and leads to lower postoperative American Shoulder and Elbow Surgeons scores and higher shoulder visual analog scale for pain.

6.
Opt Express ; 30(4): 6203-6215, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209561

RESUMEN

Efficient sorting multiple orbital angular momentum (OAM) spatial modes is a significant step in OAM multiplexing communications. Recently, wavefront shaping (WS) techniques have been implemented to manipulate light scattering through a diffuser. We reported a novel scheme for sorting multiplexed OAM modes faster and more accurately, using the complex amplitude WS based on a digital micromirror device (DMD) through a diffuser to shape the full field (phase and amplitude) of the OAM modes. In this study, we simulate this complex sorter for demultiplexing multiple modes and make a performance comparison with the previous sorter using the phase-only WS. Our results showed that for arbitrary two multiplexed modes, the sorter could achieve a high detection probability of more than 0.99. As the number of the multiplexed modes increases, the detection probability decreases to ∼0.82 when sorting seven modes, which contrasts the ∼0.71 of the phase-only sorters. We also experimentally verified the feasibility, that for arbitrary two modes, the sorter could reach a high detection probability of more than 0.99, and the complex sorter is capable of higher detection probability than the phase-only sorter under the same conditions. Hence, we anticipate that this sorter may potentially be demultiplexing multiple OAM spatial modes efficiently and quickly.

7.
Fish Shellfish Immunol ; 126: 187-196, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35588908

RESUMEN

MYC proto-oncogene (MYC), a first oncogenic nuclear transcription factor isolated from the human genome, belongs to the helix loop helix/leucine zipper protein family (bHLHzip). MYC plays an important part in the process of various physiological and biochemical of vertebrate, such as cell growth, proliferation, cycle, and autophagy. However, its molecular regulation mechanism and function in invertebrates are still unclear. In this study, a novel transcription factor MYC gene was screened, cloned, and characterized from Penaeus vannamei. The open reading frame of PvMYC was 1593bp, encode a polypeptide of 530 amino acids with molecular weight of 58.5 kDa, and a theoretical PI of 5.75. The results of tissue distribution showed that PvMYC was constitutively expressed in all detected tissues, and highest expression in hepatopancreas. The expression level of PvMYC up-regulated significantly and responded to low temperature stress by nuclear ectopic after low temperature stress. Overexpression of PvMYC in shrimp hemocytes negatively regulated the expression of Beclin-1 and reduced the conversion from LC3I to LC3II, yet p62 was decreased significantly. Meanwhile, RAPA eliminated the inhibition of autophagy caused by overexpression of PvMYC. ROS levels and autophagy flux showed the similar trend under low temperature stress after silencing PvMYC. The expression levels of Beclin-1, key ATG gene and LC3II increased significantly, while p62 decreased significantly under the same conditions. In addition, the Total hemocyte count (THC) decreased sharply, and accelerated the injury of hepatopancreas under low temperature stress after silencing PvMYC. Collectively, these results suggest that PvMYC has vital role in the cold adaptation mechanism of P. vannamei by negatively regulating autophagy.


Asunto(s)
Penaeidae , Animales , Autofagia/genética , Beclina-1 , Hepatopáncreas , Penaeidae/genética , Factores de Transcripción
8.
Fish Shellfish Immunol ; 122: 48-56, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35077870

RESUMEN

TBC domain family 7 (TBC1D7) is one of the subunits of tuberous sclerosis complex (TSC) and an important regulator of autophagosome biogenesis. However, the function of TBC1D7 is not fully understood in crustaceans. In the present study, TBC1D7 was identified from Penaeus vannamei. The complete coding sequence of PvTBC1D7 was of 960 bp encoding a predicted polypeptide of 319 amino acids with one conserved TBC domain, which shared high similarity with TBC1D7 of that other species. The mRNA of PvTBC1D7 was highly expressed in hemocyte and hepatopancreas, and the PvTBC1D7 protein was localized specifically in the cytoplasm of hemocyte of shrimp. Besides, PvTBC1D7 was co-localized with PvTSC1 in the cytoplasm of shrimp, indicating that there might existed a binding relationship between PvTBC1D7 and PvTSC1. During the ammonia nitrogen stress, the mRNA transcripts of PvTBC1D7 were significantly upregulated in hemocyte, hepatopancreas, and gill. Functionally, overexpression of PvTBC1D7 in vitro restored the inhibition to autophagy caused by chloroquine (CLQ) and increased the autophagy level, while the silencing of PvTBC1D7 could inhibit the autophagy. More importantly, after interfering with PvTBC1D7, the autophagy level decreased significantly both in hepatopancreas and hemocyte of P. vannamei, the mRNA expression of PvmTOR was increased remarkably with the significantly decrease of autophagy-related genes (PvATG12 and PvATG14). And the reduction of PvTBC1D7 remarkably exacerbated the damage of hepatopancreas, increased the accumulation of ROS, and reduced the survival proportion of shrimp under ammonia nitrogen stress. Altogether, these results indicated that PvTBC1D7 might positively regulate the autophagy by stabilizing the negative regulation of mTOR by TSC complex, reduce the oxidative stress damage and improve shrimp ammonia nitrogen tolerance.


Asunto(s)
Penaeidae , Amoníaco/farmacología , Animales , Autofagia , Nitrógeno , Estrés Fisiológico , Regulación hacia Arriba
9.
Fish Shellfish Immunol ; 123: 238-247, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35278640

RESUMEN

Vibrio alginolyticus is a devastating bacterial pathogen of Pacific white shrimp (Litopenaeus vannamei), which often causes acute hepatopancreatic necrosis syndrome (AHPNS) and early mortality syndrome (EMS). Elucidation of molecular mechanisms of L. vannamei in responding to infection is essential for controlling the epidemic. In the present study, transcriptomic profiles of L. vannamei hepatopancreas were explored by injecting with PBS or V. alginolyticus. Hepatopancreas morphology of L. vannamei was also assessed. The result reveals that compared with the hepatopancreas of PBS group, the storage cells (R-cell), secretory cells (B-cell) and star-shaped polygonal structures of the lumen were disappeared and necrotic after challenged by V. alginolyticus at 24 h. Transcriptome data showed that a total of 314 differential expression genes were induced by V. alginolyticus, with 133 and 181 genes up- and down-regulated, respectively. These genes were mainly associated with lysosome pathway, glycerophospholipid metabolism, drug metabolism-other enzymes, cysteine and methionine metabolism, aminoacyl-tRNA biosynthesis and PPAR signal pathway. Among these pathways, the lysosome pathway, glycerophospholipid metabolism and PPAR signal pathway were both related with lipid metabolism. Therefore, we detected the lipid accumulation in hepatopancreas by Oil Red O staining, TG and CHOL detection and the relative mRNA expression of several lipid metabolism related genes in the hepatopancreas of shrimp after challenge to V. alginolyticus. The present data reveals that lipids from the L. vannamei are nutrient sources for the V. alginolyticus and define the fate of the infection by modulating lipid homeostasis. These findings may have important implication for understanding the L. vannamei and V. alginolyticus interactions, and provide a substantial dataset for further research and may deliver the basis for preventing the bacterial diseases.


Asunto(s)
Hepatopáncreas , Penaeidae , Animales , Perfilación de la Expresión Génica , Glicerofosfolípidos/metabolismo , Hepatopáncreas/metabolismo , Inmunidad Innata/genética , Lípidos , Penaeidae/microbiología , Receptores Activados del Proliferador del Peroxisoma/genética , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Vibrio alginolyticus/genética
10.
Cell Mol Biol Lett ; 27(1): 87, 2022 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-36209075

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with invasive and metastatic characteristics and poor prognosis. Intracellular protein homeostasis is associated with invasion and metastasis of pancreatic cancer, but the specific molecular mechanism remains unclear. Our previous studies have revealed that DNAJB11, a key protein in protein homeostasis, is secreted by exosomes in the supernatant of dissociated pancreatic cancer cells with high metastasis. The results from transcriptome sequencing and co-immunoprecipitation (Co-IP)-based liquid chromatography with tandem mass spectrometry (LC-MS/MS) showed that depletion of DNAJB11 levels could increase HSPA5 expression and induce endoplasmic reticulum stress through the PRKR-like endoplasmic reticulum kinase signaling pathway in pancreatic cancer cells. Furthermore, exosomal DNAJB11 promoted cell development of PC cells in vitro and in vivo. In addition, exosomal DNAJB11 could regulate the expression of EGFR and activate the downstream MAPK signaling pathway. Clinical blood samples were collected to evaluate the potential of exosome DNAJB11 as a diagnostic biomarker and therapeutic target for the treatment of pancreatic cancer. This study could provide a new theoretical basis and potential molecular targets for the treatment of pancreatic cancer.


Asunto(s)
Neoplasias Pancreáticas , Espectrometría de Masas en Tándem , Animales , Biomarcadores , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Cromatografía Liquida , Receptores ErbB/genética , Receptores ErbB/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP40/metabolismo , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Desnudos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas
11.
Bioorg Chem ; 115: 105212, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34333423

RESUMEN

Eighteen derivatives of pentacyclic triterpene carboxylic acids (Maslinic acid, Corosolic acid and Asiatic acid) have been prepared by coupling the piperazine complex of l-amino acids at the C-28 site of the parent compounds. The α-glucosidase inhibitory activities of the pristine derivatives were evaluated in vitro. The results indicated that the inhibitory activity of some compounds (15e IC50 = 591 µM, 16e IC50 = 423 µM) was closed to that of the reference acarbose (IC50 = 347 µM) in ethanol-water system. In addition, compound 16e (IC50 = 380 µM) showed superior inhibitory activity than acarbose (IC50 = 493 µM) in the measurement system with DMSO as solvent. The comparison of two different solvent systems showed that the derivatives had better α-glucosidase inhibitory activity in the DMSO system than that of in ethanol-water system. Regrettably, all of the as-synthesized derivatives exhibited inferior α-glucosidase inhibitory activities than those of the parent compounds in both test solvent systems. Furthermore, the result of enzyme kinetics demonstrated that the inhibition mechanism of compound 16e was noncompetitive inhibition with the inhibition constant Ki = 552 µM.


Asunto(s)
Aminoácidos/farmacología , Ácidos Carboxílicos/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Triterpenos Pentacíclicos/farmacología , Piperazina/farmacología , alfa-Glucosidasas/metabolismo , Aminoácidos/química , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/química , Relación Dosis-Respuesta a Droga , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Estructura Molecular , Triterpenos Pentacíclicos/síntesis química , Triterpenos Pentacíclicos/química , Piperazina/química , Relación Estructura-Actividad
12.
Ecotoxicol Environ Saf ; 225: 112774, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34536791

RESUMEN

MicroRNAs (miRNAs) are critical post-transcriptional regulators, which play a crucial role in resistance to adverse environmental stress by regulating autophagy. However, the mechanism of miRNA involved in the autophagy regulation of shrimp under ammonia nitrogen stress is still limited. In the present study, ammonia nitrogen could induce hepatopancreas injury and oxidative stress of P. vannamei, and significantly increase the content of ROS in hemocytes by flow cytometry. Simultaneously, it is accompanied by autophagy occurred in the hemocytes and hepatopancreas. Furthermore, the qRT-PCR analysis revealed that the expression of pva-miR-252 in P. vannamei decreased significantly after ammonia nitrogen stress, and pva-miR-252 negatively regulated PvPI3K by binding to 3'UTR of PvPI3K by double-luciferase assay. Pva-miR-252 overexpression could significantly increase the level of autophagy, and restore the autophagy inhibition caused by Chloroquine in vitro , whereas silencing of pva-miR-252 resulted in the opposite effect. More importantly, overexpression of pva-miR-252 could enhance the activity of antioxidant enzymes and reduced the production of ROS of shrimp under ammonia nitrogen stress. In conclusion, pva-miR-252 could positively regulate autophagy through PvPI3K and improve the antioxidant enzyme activity of P. vannamei under ammonia nitrogen stress, and our study provides a novel theoretical molecular mechanism for further understanding the shrimp cope with a high ammonia nitrogen environment.


Asunto(s)
MicroARNs , Penaeidae , Amoníaco/toxicidad , Animales , Autofagia , MicroARNs/genética , Nitrógeno , Estrés Oxidativo , Penaeidae/genética
13.
Bioorg Chem ; 97: 103694, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32120080

RESUMEN

Combining two bioactive moieties by covalent bond into a novel single hybrid biological entity in view of the principle of active splicing, twenty-two C28-modified derivatives of pentacyclic dihydroxytriterpene carboxylic acids with saturated nitrogen heterocycle segments (i.e. 1-deoxynojirimycin or piperazines) have been synthesized. The inhibitory activities of all final target compounds on α-glucosidase were evaluated in vitro. The results of α-glucosidase inhibition assay indicate that some derivatives (e.g. 4b: IC50 = 1468.4 µM; 12b: IC50 = 499.6 µM 12c: IC50 = 768.5 µM, 13c: IC50 = 819.2 µM) show superior inhibitory activity in α-glucosidase than that of the precursor maslinic acid (IC50 = 2540.6 µM) or corosolic acid (IC50 = 1363.7 µM), in which compound 12b (IC50 = 499.6 µM) possesses stronger inhibitory activity than that of acarbose (IC50 = 606 µM). In addition, the result of enzyme kinetics study reveals that the inhibitory mechanism of the compound 12b is non-competitive inhibition and the inhibition constant Ki is 570 µM. The binding interaction between compounds with α-glucosidase are predicted by molecular docking simulation.


Asunto(s)
Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Triterpenos/química , Triterpenos/farmacología , Técnicas de Química Sintética , Inhibidores de Glicósido Hidrolasas/síntesis química , Humanos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Saccharomyces cerevisiae/enzimología , Triterpenos/síntesis química , alfa-Glucosidasas/metabolismo
14.
Bioorg Chem ; 86: 277-287, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30735848

RESUMEN

Twenty maslinic acid and corosolic acid derivatives were obtained by coupling with l-amino acids at C-28 position. The α-glucosidase inhibitory activities of the present compounds were evaluated in vitro. Results reveal that some of the derivatives exhibit a better α-glucosidase inhibitory activity than that of acarbose in the test conditions of ethanol-water solution and DMSO. It is worth noting that maslinic acid and corosolic acid derivatives coupled aspartic acid (9f: IC50 = 382 µm and 10f: IC50 = 364 µm, respectively) have the best water solubility and thus presented higher inhibitory activity than that of acarbose (IC50 = 484 µm). Unfortunately, all of the derivatives possess lower inhibitory properties of α-glucosidase than those of the parent compounds in the measurement system of DMSO solution, even if the derivatives exhibit better water solubility than that of the parent compounds.


Asunto(s)
Aminoácidos/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Triterpenos/farmacología , alfa-Glucosidasas/metabolismo , Aminoácidos/química , Relación Dosis-Respuesta a Droga , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Conformación Molecular , Solubilidad , Relación Estructura-Actividad , Triterpenos/síntesis química , Triterpenos/química , Agua/química
15.
Appl Opt ; 58(22): 6085-6090, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31503929

RESUMEN

Recently, orbital angular momentum (OAM) beams have been applied in underwater optical communication (UWOC) to build a high-capacity communication link. However, a wave-front-sensitive OAM beam suffers significant distortion due to oceanic turbulence (OT), resulting in considerable intermodal crosstalk that degrades the UWOC performance. Herein, we propose and demonstrate an adaptive optics (AO)-based correction approach with a phase retrieval algorithm (PRA) to compensate for the distorted OAM beams induced by OT. In a simulation, an OT model with the random phase screen method is utilized. Two PRAs, the Gerchberg-Saxton algorithm (GSA) and the hybrid input-output algorithm (HIOA), are utilized to reconstruct the distorted phase-front of the OAM beam. The simulation results illustrate that the PRA-based AO approach can effectively compensate for the distorted OAM beam and improve the bit error rate performance in an oceanic channel. Additionally, the compensation performance of HIOA-based AO is superior to that of GSA-based AO in terms of convergence performance. This work verifies the feasibility and validity of a PRA-based AO approach in underwater turbulence optical communication and provides new insights into the OAM underwater communication system.

16.
Opt Express ; 26(21): 27849-27864, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-30469843

RESUMEN

In this paper, a novel turbo-coded 16-ary orbital angular momentum - shift keying-free space optical (OAM-SK-FSO) communication system combining a convolutional neural network (CNN) based adaptive demodulator under strong atmospheric turbulence is proposed for the first time. The feasibility of the scheme is verified by transmitting a 256-grayscale two-dimensional digital image. The bit error ratio (BER) performance of the system is investigated and the effect of different factors such as turbulence strength, propagation distance, code rate, length of random interleaver and length of bit interleaver is also taken into account. An advanced encoder/decoder structure and mapping scheme are applied to diminish the influence of CNN misclassification and reduce the BER effectively. With the optimal encoder/decoder structure and CNN model settings, the BER varies from 0 to 4.89×10-4 when the propagation distance increases from 200m to 1000m for a given turbulence strength Cn2 equals 5×10-14m-2/3. For a determined propagation distance equals 400m, the BER ranges from 0 to 4.01×10-4 when Cn2increases from 1×10-15m-2/3 to 4×10-13m-2/3. Our numerical simulations demonstrate that the proposed system can provide better BER performance under strong atmospheric turbulence and conditions when the classification ability of CNN is limited.

17.
J Sep Sci ; 41(16): 3232-3240, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30009500

RESUMEN

In this work, high-performance liquid chromatography with diode array detection was applied for the simultaneous determination of andrographolide and dehydroandrographolide in Andrographis paniculata and its preparations. As a result of the incomplete baseline separation caused by complex backgrounds, the classical univariate calibration method failed to determine accurate contents of the analytes. On this occasion, chemometric second-order calibration based on the well-known alternating trilinear decomposition algorithm was then explored to serve as a post-experimental remedial tool to solve this problem. By using the intelligent "mathematical separation" of alternating trilinear decomposition, the peak areas of the analytes do not need to be directly measured and the predictive results become accurate. The contents of andrographolide and dehydroandrographolide were determined to be (7.95 ± 0.15) and (1.85 ± 0.02) µg/mL for Andrographis paniculata, (1.34 ± 0.01) and (5.53 ± 0.04) µg/mL for its preparations, which was in agreement with those obtained by a reference liquid chromatography with mass spectrometry method. This study showed the superiority of second-order calibration method over classical univariate calibration method for simultaneous determination of multi-analytes in complex samples. It also proved that second-order calibration may be a good choice for remedying incomplete baseline separation problem, with the accompanied reduction of experimental burden and toxic organic solvents as well as analysis time and cost.


Asunto(s)
Andrographis/química , Diterpenos/análisis , Calibración , Cromatografía Líquida de Alta Presión , Conformación Molecular
18.
Appl Opt ; 57(26): 7644-7650, 2018 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-30461834

RESUMEN

Atmospheric turbulence is a major challenge for practical orbital angular momentum (OAM)-based free-space optical (FSO) communication systems that causes intermodal crosstalk and degrades the performance of the system. Herein, we propose a hybrid input-output algorithm (HIOA)-based adaptive optics (AO) system to compensate for distorted OAM beams. The principle and parameters of the HIOA-based AO system in an OAM-based FSO system are analyzed, and the performance is discussed. The simulation results indicate that the HIOA-based AO system can effectively correct distorted OAM beams and that the HIOA improves the compensation performance and convergence speed compared to the traditional Gerchberg-Saxton algorithm. Moreover, we analyze the compensation performance based on different probe beams. Using an OAM beam with state l=1 as a probe beam can yield better correction effects than a Gaussian beam. This work verifies the feasibility of using an HIOA for adaptive turbulence compensation and provides new insights into OAM communication systems.

19.
J Sep Sci ; 38(16): 2781-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26017356

RESUMEN

A simple method has been developed by combining high-performance liquid chromatography with diode array detection with the alternating trilinear decomposition method for simultaneous determination of four tyrosine kinase inhibitors in different human plasma samples. Chromatographic separation of the analytes was performed on a reversed-phase column with methanol (65%, v/v, A) and 0.1% aqueous solution of formic acid (35%, v/v, B). Analysis time was 5.0 min per run and analytes could be completely eluted within 2.8--3.8 min. The calibration concentration ranges of vandetanib, pazopanib, afatinib and dasatinib were designed as 0.50-6.10, 0.50-6.10, 0.70-7.00 and 0.70-7.00 µg·mL(-1), respectively. The intra- and inter-day RSDs ranged between 0.1 and 8.9%. Quantitative information could be extracted from the unsegregated interferences of different human plasma samples with the aid of the "second-order advantage" of three-way (second-order) calibration methods. All results demonstrated that the proposed method for direct quantitative analysis of four tyrosine kinase inhibitors in different complex systems possessed good characteristics of rapidity, sensitivity and efficiency, and it is expected to be an attractive choice in the fast analysis of clinical samples.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Proteínas Tirosina Quinasas/sangre , Calibración , Cromatografía Líquida de Alta Presión/instrumentación , Humanos , Proteínas Tirosina Quinasas/química
20.
Fish Shellfish Immunol ; 40(1): 190-6, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25010674

RESUMEN

Guava (Psidium guajava L.) leaf extracts have antiviral and antibacterial activity against shrimp pathogens such as yellow-head virus (YHV), white spot syndrome virus (WSSV), and Vibrio harveyi, which make it a potential water disinfectant for use in shrimp culture. In this study, the safety of guava leaf supplementation in shrimp was evaluated by studying its influence on growth and the non-specific immune response of Penaeus monodon. Six diets containing different levels of guava leaves (0% [basal diet], 0.025% [G1], 0.05% [G2], 0.1% [G3], 0.2% [G4], and 0.4% [G5]) were fed to groups of shrimp (1.576 ± 0.011 g body weight) in triplicate for 56 days. Growth performance (final body weight, WG, PWG, SGR) of shrimp fed guava leaf diets was significantly higher (P < 0.05) than that of shrimp fed on the basal diet. The G1 diet resulted in the highest body weight gain (308.44%), followed by the G2 (295.45%), G3 (283.05%), G5 (281.29%), G4 (276.11%), and finally the basal diet (214.58%). Survival of shrimp in the G1 diet group was higher than that of shrimp in the control and the other experimental groups; however, no statistical differences (P > 0.05) were found. Dietary supplementation with guava leaf improved the activities of prophenoloxidase (PO) and nitric oxide synthase (NOS) in serum, and of superoxide dismutase (SOD), acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LSZ) both in serum and hepatopancreas of shrimp. In the experimental groups, the activities of these enzymes followed a similar pattern of change; they increased initially at low levels of dietary supplementation and then decreased with increasing concentrations of dietary guava leaf. Serum PO and SOD activities in shrimp fed the G1 diet reached 7.50 U ml(-1) and 178.33 U ml(-1), respectively, with PO activity being significantly higher than in controls. In shrimp fed the G1 diet, SOD, ACP, and AKP activities in hepatopancreas were significantly higher than in the controls, reaching 57.32 U g(-1), 23.28 U g(-1), and 19.35 U g(-1) protein, respectively. The highest activities of serum ACP, AKP, LSZ, and of hepatopancreas LSZ, were observed in the G3 diet group. Total nitric oxide synthase (TNOS) activity was highest (64.80 U ml(-1)) in the G4 diet group, which was significantly higher than that observed in the control group. These results suggest that dietary guava leaf supplementation could enhance the growth performance and non-specific immune response of P. monodon. Therefore, guava leaf is considered safe for use as a water disinfectant in shrimp culture.


Asunto(s)
Inmunidad Innata/efectos de los fármacos , Penaeidae/efectos de los fármacos , Extractos Vegetales/efectos adversos , Psidium/efectos adversos , Alimentación Animal/efectos adversos , Alimentación Animal/análisis , Animales , Acuicultura , Dieta/efectos adversos , Suplementos Dietéticos/efectos adversos , Suplementos Dietéticos/análisis , Penaeidae/enzimología , Penaeidae/crecimiento & desarrollo , Penaeidae/inmunología , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Hojas de la Planta/efectos adversos , Hojas de la Planta/química , Psidium/química
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