Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 129
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Plant Biotechnol J ; 22(6): 1435-1452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38194521

RESUMO

Wolfberry is a plant with medicinal and food values. However, its bioactive ingredients and the corresponding genetic bases have not been determined. Here, we de novo generated a chromosome-level genome assembly for wolfberry, yielding a genome sequence of ~1.77 Gb with contig N50 of 50.55 Mb and 39 224 predicted gene models. A variation map, using 307 re-sequenced accessions, was called based on this genome assembly. Furthermore, the fruit metabolome of these accessions was profiled using 563 annotated metabolites, which separated Lycium barbarum L. and non-L. barbarum L. The flavonoids, coumarins, alkaloids and nicotinic acid contents were higher in the former than in the latter. A metabolite-based genome-wide association study mapped 156 164 significant single nucleotide polymorphisms corresponding to 340 metabolites. This included 19 219 unique lead single nucleotide polymorphisms in 1517 significant association loci, of which three metabolites, flavonoids, betaine and spermidine, were highlighted. Two candidate genes, LbUGT (evm.TU.chr07.2692) and LbCHS (evm.TU.chr07.2738), with non-synonymous mutations, were associated with the flavonoids content. LbCHS is a structural gene that interacts with a nearby MYB transcription factor (evm.TU.chr07.2726) both in L. barbarum and L. ruthenicum. Thus, these three genes might be involved in the biosynthesis/metabolism of flavonoids. LbSSADH (evm.TU.chr09.627) was identified as possibly participating in betaine biosynthesis/metabolism. Four lycibarbarspermidines (E-G and O) were identified, and only the lycibarbarspermidines O content was higher in L. barbarum varieties than in non-L. barbarum varieties. The evm.TU.chr07.2680 gene associated with lycibarbarspermidines O was annotated as an acetyl-CoA-benzylalcohol acetyltransferase, suggesting that it is a candidate gene for spermidine biosynthesis. These results provide novel insights into the specific metabolite profile of non-L. barbarum L. and the genetic bases of flavonoids, betaine and spermidine biosynthesis/metabolism.


Assuntos
Betaína , Flavonoides , Estudo de Associação Genômica Ampla , Lycium , Polimorfismo de Nucleotídeo Único , Espermidina , Flavonoides/metabolismo , Lycium/genética , Lycium/metabolismo , Espermidina/metabolismo , Betaína/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Genoma de Planta/genética , Frutas/genética , Frutas/metabolismo
2.
Gen Comp Endocrinol ; 354: 114543, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692521

RESUMO

Relaxin3 (rln3) has been associated with various emotional and cognitive processes, including stress, anxiety, learning, memory, motivational behavior, and circadian rhythm. Notably, previous report revealed that Rln3a played an indispensable role in testicular development and male fertility in Nile tilapia (Oreochromis niloticus). However, the underlying molecular mechanisms remain largely unknown. We found that Rln3a is expressed exclusively in the diencephalon* (Di*) of the brain. Deficiency of Rln3a resulted in a significant increase in serum dopamine level and an upregulation of gene expression of gnrh1 and kisspeptin2. To further elucidate the role of Rln3a in fish fertility, we collected two different regions of Di* and hypothalamus (Hyp) tissues for subsequent RNA-seq analysis of both wild-type (rln3a+/+) and rln3a-/- male tilapia. Upon the transcriptomic data, 1136 and 755 differentially expressed genes (DEGs) were identified in the Di* and Hyp tissues, respectively. In Di*, the up-regulated genes were enriched in circadian rhythm, chemical carcinogenesis, while the down-regulated genes were enriched in type II diabetes mellitus, dopaminergic synapse, and other pathways. In Hyp, the up-regulated genes were enriched in circadian rhythm, pyrimidine metabolism, while the down-regulated genes were enriched in type I diabetes mellitus, autoimmune thyroid disease, and other pathways. Subsequently, the results of both qRT-PCR and FISH assays highlighted a pronounced up-regulation of core circadian rhythm genes, cry1b and per3, whereas genes such as clocka, clockb, and arntl exhibited down-regulation. Furthermore, the genes associated with dopamine biosynthesis were significantly increased in the Hyp. In summary, the mutation of rln3a in male tilapia resulted in notable changes in circadian rhythm and disease-linked signaling pathways in the Di* and Hyp. These changes might account for the fertility defects observed in rln3a-/- male mutants in tilapia.


Assuntos
Encéfalo , Ciclídeos , Fertilidade , Animais , Masculino , Ciclídeos/genética , Ciclídeos/metabolismo , Encéfalo/metabolismo , Fertilidade/genética , Relaxina/genética , Relaxina/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo
3.
Molecules ; 29(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675644

RESUMO

At present, the main raw material for producing graphene is graphite ore. However, researchers actively seek alternative resources due to their high cost and environmental problems. Biomass waste has attracted much attention due to its carbon-rich structure and renewability, emerging as a potential raw material for graphene production to be used in sports equipment. However, further progress is required on the quality of graphene produced from waste biomass. This paper, therefore, summarizes the properties, structures, and production processes of graphene and its derivatives, as well as the inherent advantages of biomass waste-derived graphene. Finally, this paper reviews graphene's importance and application prospects in sports since this wonder material has made sports equipment available with high-strength and lightweight quality. Moreover, its outstanding thermal and electrical conductivity is exploited to prepare wearable sensors to collect more accurate sports data, thus helping to improve athletes' training levels and competitive performance. Although the large-scale production of biomass waste-derived graphene has yet to be realized, it is expected that its application will expand to various other fields due to the associated low cost and environmental friendliness of the preparation technique.


Assuntos
Biomassa , Grafite , Equipamentos Esportivos , Humanos , Condutividade Elétrica , Grafite/química , Esportes , Equipamentos Esportivos/economia , Gerenciamento de Resíduos/economia
4.
Int Wound J ; 21(2): e14769, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38351506

RESUMO

Postoperative wound infections (PWIs) pose a significant challenge in colorectal cancer surgeries, leading to prolonged hospital stays and increased morbidity. This systematic review and meta-analysis evaluated the efficacy of the traditional Chinese medicine (TCM) combination of Jie Geng and Huang Qi in reducing PWIs following colorectal cancer surgeries. Adhering to PRISMA guidelines, we focused on seven randomized controlled trials (RCTs) involving 1256 patients, examining the incidence of PWIs within 30 days post-surgery, alongside secondary outcomes such as length of hospital stay and antibiotic use. The analysis revealed a significant reduction in PWI incidence in the TCM-treated group compared to controls, with a Risk Ratio of 0.21 (95% CI: 0.14 to 0.30, p < 0.01), a notable decrease in hospital stay (Mean Difference: 1.2 days, 95% CI: 0.15 to 1.28 days, p < 0.01) and a significant reduction in antibiotic use (Risk Ratio: 0.24, 95% CI: 0.16 to 0.36, p < 0.01). These findings suggest that Jie Geng and Huang Qi in TCM could be an effective adjunct in postoperative care for colorectal cancer surgeries, underscoring the need for further high-quality RCTs to substantiate these results and explore the underlying mechanisms.


Assuntos
Astragalus propinquus , Neoplasias Colorretais , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Chinesa , Infecção da Ferida Cirúrgica/prevenção & controle , Medicamentos de Ervas Chinesas/uso terapêutico , Antibacterianos/uso terapêutico , Neoplasias Colorretais/cirurgia
5.
Int Wound J ; 21(4): e14847, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38584331

RESUMO

Due to the high risks of postoperative complications brought on by gastric cancer, traditional Chinese medicine (TCM) as a commonly used therapy, has exerted its vital role in postoperative recovery care. In this sense, this meta-analysis was conducted to explore the related documents about TCM's impact on gastric cancer postoperative recovery. During the research, we explored a total of 1549 results from databases PubMed, China National Knowledge Infrastructure (CNKI), Embase, Cochrane Library and Web of Science (WoS). Thirty-two clinical randomized trials (RCTs) were then selected and analysed for this meta-analysis by using the software RevMan 5.4 (under PRISMA 2020 regulations), with a population of 3178 patients. Data prove that TCM therapy reduced the risks for postoperative complications exposure by an estimated average of 19% (95% CI). Among the complications, TCM therapy suppressed the risks of wound infection and incisional infections by 53% and 48% respectively. Meanwhile, the patient's wound healing duration exhibited a significant reduction compared to those without TCM treatment, with a difference at around 0.74 days (95% CI). TCM also exerted its potential to strengthen the patient's immune and health conditions, leading to a significantly promoted gastrointestinal function in the patients with a shorter duration to release first exhaustion and defecation compared to those with no TCM therapy. In addition, similar promoted phenomena also exist in those patients with TCM therapy in terms of their immunity and nutritional conditions. These facts all indicate a positive impact of TCM therapy in clinical applications.


Assuntos
Medicamentos de Ervas Chinesas , Complicações Pós-Operatórias , Neoplasias Gástricas , Humanos , China , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos , Complicações Pós-Operatórias/terapia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia
6.
Int Ophthalmol ; 44(1): 262, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38913192

RESUMO

BACKGROUND: Macular edema (ME) is a common complication following branch retinal vein occlusion (BRVO) and is also the main reason for visual impairment. This study aimed to compare the efficacy and safety of intravitreal ranibizumab (IVR) or dexamethasone implant (IDI) monotherapy, as well as the combination of IVR and IDI injections, in patients with ME secondary to branch retinal vein occlusion (BRVO). METHODS: This multicenter, prospective, and comparative study included 292 patients with unilateral ME involvement (total of 292 eyes) secondary to BRVO. The patients were randomly assigned to three groups and followed up for 12 months. Patients in group 1 (n = 96) were treated with 3-dose loading IVR injections followed by a pro re nata (PRN) regimen. Patients in group 2 (n = 98) received IVR combined with IDI injection, followed by IVR PRN regimen. Patients in group 3 (n = 98) were treated with IDI injection, followed by repeated IDI injection based on clinical necessity. Best corrected visual acuity (BCVA), central retinal thickness (CRT), complications, and frequency of injections were recorded and compared between the three groups. RESULTS: At baseline, the three groups did not differ in age, gender, duration of ME, BCVA, IOP, and CRT (P > 0.05). Mean number of total injections per eye within 12 months were 7.1 ± 2.3 (range 4-9) in group 1, 3.7 ± 1.5 (range 2-6) in group 2, and 1.8 ± 0.4 (range 1-3) in group 3. There was a statistical difference in the number of injections between group 1 and group 2 (P = 0.037). Eyes in group 3 received fewer injections than those in group 2, but the difference was not statistically significant (P = 0.052). BCVA improvement and CRT reduction were achieved in all groups and there was no significant difference between the three groups at the end of the 12th month. However, IOP elevation and cataract progression were more frequent in group 3, especially in those patients who received repeated IDI injections. CONCLUSION: Three therapeutic regimens had comparable efficacy in treating ME secondary to BRVO. Combination therapy had an advantage in maintaining good effect with fewer re-injections and complications. TRIAL REGISTRATION INFORMATION: The study complied with the principles of the Declaration of Helsinki and was approved by Xi'an Aier Ancient City Eye Hospital, Xi'an Aier Eye Hospital, and Xianyang Aier Eye Hospital ethics committees (2022SF-367).


Assuntos
Inibidores da Angiogênese , Dexametasona , Implantes de Medicamento , Quimioterapia Combinada , Glucocorticoides , Injeções Intravítreas , Edema Macular , Ranibizumab , Oclusão da Veia Retiniana , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/tratamento farmacológico , Oclusão da Veia Retiniana/diagnóstico , Ranibizumab/administração & dosagem , Masculino , Feminino , Dexametasona/administração & dosagem , Edema Macular/etiologia , Edema Macular/tratamento farmacológico , Edema Macular/diagnóstico , Estudos Prospectivos , Pessoa de Meia-Idade , Inibidores da Angiogênese/administração & dosagem , Glucocorticoides/administração & dosagem , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Idoso , Seguimentos
7.
Plant Physiol ; 189(4): 2091-2109, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35522025

RESUMO

High temperature (HT) causes male sterility and decreases crop yields. Our previous works have demonstrated that sugar and auxin signaling pathways, Gossypium hirsutum Casein kinase I (GhCKI), and DNA methylation are all involved in HT-induced male sterility in cotton. However, the signaling mechanisms leading to distinct GhCKI expression patterns induced by HT between HT-tolerant and HT-sensitive cotton anthers remain largely unknown. Here, we identified a GhCKI promoter (ProGhCKI) region that functions in response to HT in anthers and found the transcription factor GhMYB4 binds to this region to act as an upstream positive regulator of GhCKI. In the tapetum of early-stage cotton anthers, upregulated expression of GhMYB4 under HT and overexpressed GhMYB4 under normal temperature both led to severe male sterility phenotypes, coupled with enhanced expression of GhCKI. We also found that GhMYB4 interacts with GhMYB66 to form a heterodimer to enhance its binding to ProGhCKI. However, GhMYB66 showed an expression pattern similar to GhMYB4 under HT but did not directly bind to ProGhCKI. Furthermore, HT reduced siRNA-mediated CHH DNA methylations in the GhMYB4 promoter, which enhanced the expression of GhMYB4 in tetrad stage anthers and promoted the formation of the GhMYB4/GhMYB66 heterodimer, which in turn elevated the transcription of GhCKI in the tapetum, leading to male sterility. Overall, we shed light on the GhMYB66-GhMYB4-GhCKI regulatory pathway in response to HT in cotton anthers.


Assuntos
Gossypium , Infertilidade Masculina , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/metabolismo , Temperatura Alta , Humanos , Masculino , Temperatura
8.
Opt Express ; 31(16): 26888-26897, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710538

RESUMO

The link alignment is a challenge in underwater wireless optical communication (UWOC). This paper proposes a UWOC system adopting a fisheye lens with a field of view (FOV) of ±90° at the receiver to alleviate alignment requirement, and a mobile scanning device (MSD) is exploited to track the variation of the imaging position generated by the fisheye lens due to different incidence angles. In a 7-m tap water channel, a transmission with a data rate of 400 Mbps and an FOV of ±90° is realized with 16-quadrature amplitude modulating-orthogonal frequency division multiplexing (16-QAM-OFDM) modulation and orthogonal matching pursuit (OMP) channel estimation algorithm.

9.
Opt Lett ; 48(11): 3023-3026, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262271

RESUMO

For underwater wireless optical communication (UWOC) systems, using an omnidirectional light source to construct a broadcast system will require considerable energy due to high geometric loss and water attenuation. In addition, high-sensitivity photon detectors usually have a limited dynamic range, therefore limiting communication distance. In this Letter, a broadcast UWOC system, based on liquid crystal variable retarders (LCVRs) and polarization beam splitters (PBSs), is proposed to allocate user power in accordance with user-specific channel conditions. By adjusting the driving alternating current (AC) voltage of LCVRs to change the input light polarization, different proportions of light can be allocated to different PBS ports before broadcasting to different users. In a dual-user transmitter for the proof-of-concept, the output power dynamic range and the additional insertion loss for the first user are 19.17 dB and 0.91 dB, respectively. For the second user, the performance degrades to 17.33 dB and 1.26 dB, respectively. The step size of power adjustment is less than 0.063 dB. To verify the effectiveness of power adjustment in UWOC systems, a 7-m/243.2-Mbps single-user UWOC system is designed with a water attenuation coefficient ranging from 0.50 dB/m to 2.35 dB/m. All bit error rates (BERs) can decrease to below the forward error correction (FEC) limit by adjusting the LCVR driving voltage. The adjustable range of communication distance could be extended from 4.2 m to 13.19 m with a channel attenuation coefficient of 1.44 dB/m. Finally, a dual-user UWOC experiment is conducted and proves that the proposed system can still work in a multi-user system. The proposed system is proven to be effective for improving the anti-jamming capability and flexibility of UWOC networks.

10.
BMC Cancer ; 23(1): 905, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752476

RESUMO

OBJECTIVE: We aimed to evaluate the clinical efficacy and prognostic significance of intensity-modulated radiotherapy (IMRT)-based salvage concurrent chemoradiotherapy (CCRT) for patients with locoregional recurrence cervical cancer after radical hysterectomy and evaluated two salvage radiotherapy modes-regional RT (involved-field RT combined with regional lymph nodes) and local RT (involved-field RT). METHODS: Patients were enrolled retrospectively from January 2011 to January 2022 in three medical centers. Clinical outcomes were analyzed using the Kaplan-Meier method and a Cox proportional hazards model. Propensity score (PS) matching analysis was used to compare the two RT groups. RESULTS: There were 72 patients underwent IMRT-based salvage CCRT. The 5-year overall survival and progression-free survival rates were 65.9% and 57.6%, respectively. Univariate analysis showed that patients with stump recurrence, a lower systemic inflammation response index (SIRI), only one metastatic lesion, and received regional RT had better prognosis than their counterparts. In multivariate analysis, recurrence site was the independent prognostic factor of OS, and SIRI was that of PFS. After PS matching, there were 15 patients each in the regional RT group and local RT group. The 5-year OS rate of regional RT group was better than that of local RT group (90.9 vs. 42.4, p = 0.021). However, there was no significant difference between them in terms of PFS rate (47.1 vs. 38.1, p = 0.195). CONCLUSION: Locoregional recurrent cervical cancer treated with IMRT-based salvage therapy has a good prognosis. Recurrence site and SIRI were independent prognostic factors. Regional RT may be a better option for patients with locoregional recurrent.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero , Feminino , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Estadiamento de Neoplasias , Recidiva Local de Neoplasia/patologia , Quimiorradioterapia , Histerectomia
11.
Cell Mol Biol (Noisy-le-grand) ; 69(4): 147-151, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37329533

RESUMO

This study aimed to investigate the relationship between MMP-2, TIMP-1, ß2-MG, hs-CRP and the progression of type 2 diabetic retinopathy (T2DM). For this purpose, 68 patients with T2DM retinopathy treated in our hospital were selected as the retinopathy group (REG), and 68 T2DM patients without retinopathy were selected as the control group (CDG). The serum levels of MMP-2, TIMP-1, ß2-MG and hs-CRP were compared between the two groups. According to the international clinical classification of T2DM non-retinopathy (NDR), the patients were divided into non-proliferative T2DM retinopathy group (NPDR) (n=28) and proliferative T2DM retinopathy group (PDR) (n=40). The levels of MMP-2, TIMP-1, ß2-MG and hs-CRP in patients with different conditions were compared. In addition, the Spearman method was used to analyze the correlation between the levels of MMP-2, TIMP-1, ß2-MG, hs-CRP and glucose and lipid metabolism and the course of disease in patients with T2DM retinopathy (DR). Logistic multiple regression was used to analyze the risk factors of DR. Results showed that the levels of serum MMP-2, ß2-MG and hs-CRP in PDR groups were raised than those in NPDR and NDR, while the serum TIMP-1 level was reduced. The levels of MMP-2, ß2-MG and hs-CRP were positively correlated with the levels of HbA1c, TG and the course of disease in DR patients, while the levels of TIMP-1 in DR patients were negatively correlated with the levels of HbA1c, TG and the course of disease. The results of multivariate Logistic regression model showed that MMP-2, ß2-MG and hs-CRP were independent risk factors for DR, and TIMP-1 was the protective factor for DR. In conclusion, the changes of peripheral blood MMP-2, TIMP-1, hs-CRP and ß2-MG levels are closely related to the progression of T2DM retinopathy.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicações , Proteína C-Reativa/metabolismo , Hemoglobinas Glicadas , Inibidor Tecidual de Metaloproteinase-1 , Metaloproteinase 2 da Matriz
12.
Sensors (Basel) ; 23(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36904780

RESUMO

Online hashing is a valid storage and online retrieval scheme, which is meeting the rapid increase in data in the optical-sensor network and the real-time processing needs of users in the era of big data. Existing online-hashing algorithms rely on data tags excessively to construct the hash function, and ignore the mining of the structural features of the data itself, resulting in a serious loss of the image-streaming features and the reduction in retrieval accuracy. In this paper, an online hashing model that fuses global and local dual semantics is proposed. First, to preserve the local features of the streaming data, an anchor hash model, which is based on the idea of manifold learning, is constructed. Second, a global similarity matrix, which is used to constrain hash codes is built by the balanced similarity between the newly arrived data and previous data, which makes hash codes retain global data features as much as possible. Then, under a unified framework, an online hash model that integrates global and local dual semantics is learned, and an effective discrete binary-optimization solution is proposed. A large number of experiments on three datasets, including CIFAR10, MNIST and Places205, show that our proposed algorithm improves the efficiency of image retrieval effectively, compared with several existing advanced online-hashing algorithms.

13.
Sensors (Basel) ; 23(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36991657

RESUMO

Non-Orthogonal Multiple Access (NOMA) has become a promising evolution with the emergence of fifth-generation (5G) and Beyond-5G (B5G) rollouts. The potentials of NOMA are to increase the number of users, the system's capacity, massive connectivity, and enhance the spectrum and energy efficiency in future communication scenarios. However, the practical deployment of NOMA is hindered by the inflexibility caused by the offline design paradigm and non-unified signal processing approaches of different NOMA schemes. The recent innovations and breakthroughs in deep learning (DL) methods have paved the way to adequately address these challenges. The DL-based NOMA can break these fundamental limits of conventional NOMA in several aspects, including throughput, bit-error-rate (BER), low latency, task scheduling, resource allocation, user pairing and other better performance characteristics. This article aims to provide firsthand knowledge of the prominence of NOMA and DL and surveys several DL-enabled NOMA systems. This study emphasizes Successive Interference Cancellation (SIC), Channel State Information (CSI), impulse noise (IN), channel estimation, power allocation, resource allocation, user fairness and transceiver design, and a few other parameters as key performance indicators of NOMA systems. In addition, we outline the integration of DL-based NOMA with several emerging technologies such as intelligent reflecting surfaces (IRS), mobile edge computing (MEC), simultaneous wireless and information power transfer (SWIPT), Orthogonal Frequency Division Multiplexing (OFDM), and multiple-input and multiple-output (MIMO). This study also highlights diverse, significant technical hindrances in DL-based NOMA systems. Finally, we identify some future research directions to shed light on paramount developments needed in existing systems as a probable to invigorate further contributions for DL-based NOMA system.

14.
Sensors (Basel) ; 23(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36991671

RESUMO

The enhanced proliferation of connected entities needs a deployment of innovative technologies for the next generation wireless networks. One of the critical concerns, however, is the spectrum scarcity, due to the unprecedented broadcast penetration rate nowadays. Based on this, visible light communication (VLC) has recently emerged as a viable solution to secure high-speed communications. VLC, a high data rate communication technology, has proven its stature as a promising complementary to its radio frequency (RF) counterpart. VLC is a cost-effective, energy-efficient, and secure technology that exploits the current infrastructure, specifically within indoor and underwater environments. Yet, despite their appealing capabilities, VLC systems face several limitations which constraint their potentials such as LED's limited bandwidth, dimming, flickering, line-of-sight (LOS) requirement, impact of harsh weather conditions, noise, interference, shadowing, transceiver alignment, signal decoding complexity, and mobility issue. Consequently, non-orthogonal multiple access (NOMA) has been considered an effective technique to circumvent these shortcomings. The NOMA scheme has emerged as a revolutionary paradigm to address the shortcomings of VLC systems. The potentials of NOMA are to increase the number of users, system's capacity, massive connectivity, and enhance the spectrum and energy efficiency in future communication scenarios. Motivated by this, the presented study offers an overview of NOMA-based VLC systems. This article provides a broad scope of existing research activities of NOMA-based VLC systems. This article aims to provide firsthand knowledge of the prominence of NOMA and VLC and surveys several NOMA-enabled VLC systems. We briefly highlight the potential and capabilities of NOMA-based VLC systems. In addition, we outline the integration of such systems with several emerging technologies such as intelligent reflecting surfaces (IRS), orthogonal frequency division multiplexing (OFDM), multiple-input and multiple-output (MIMO) and unmanned aerial vehicles (UAVs). Furthermore, we focus on NOMA-based hybrid RF/VLC networks and discuss the role of machine learning (ML) tools and physical layer security (PLS) in this domain. In addition, this study also highlights diverse and significant technical hindrances prevailing in NOMA-based VLC systems. We highlight future research directions, along with provided insights that are envisioned to be helpful towards the effective practical deployment of such systems. In a nutshell, this review highlights the existing and ongoing research activities for NOMA-based VLC systems, which will provide sufficient guidelines for research communities working in this domain and it will pave the way for successful deployment of these systems.

15.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36772786

RESUMO

To meet the transmission requirements of different users in a multiple-beam access system for underwater optical communication (UWOC), this paper proposes a novel multiple-beam space division multiple access (MB-SDMA) system by utilizing a directional radiation communication beam of the hemispherical LED arrays. The system's access users in the different beams are divided into two categories: the users with a single beam and the users with multiple beams. We also propose a power allocation algorithm that guarantees the quality of service (QoS) for single beam and multiple beam access, especially the QoS for edge users, and fairness for all users. An optimization model of power distribution under the constraints of specific light-emitting diode (LED) emission power is established for two scenarios, which ensure the user QoS for edge users and the max-min fairness for fair users. Using the Karush-Kuhn-Tucker (KKT) condition and the bisection method, we obtain the optimal power allocation expression for the two types of users in the optimization model. Through simulation, we verify that the proposed user classification and power allocation method can ensure the fairness of fair users on the premise of ensuring the QoS of edge users. At the same time, we know that the number of users will affect the improvement of the minimum rate, and the throughput of the non-orthogonal multiple access (NOMA) system is greatly improved compared with the traditional orthogonal multiple access (OMA) systems.

16.
J Environ Manage ; 348: 119375, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37883834

RESUMO

Grasslands provide multiple ecosystem services (ESs) including provisioning, regulating, supporting, and cultural services that are largely affected by livestock grazing. Linking plant functional traits (PFTs) to ecosystem processes and functions has attracted extensive ecological research to explore the responses and inter-relations of ecosystem services to environmental and management changes. However, little information is available on the links between PFTs and ESs in most ecosystems. We conducted a grazing experiment to investigate the response of PFTs at different levels, including in plant organs (leaves and stems), individual plants, and the overall community in a typical steppe region of Inner Mongolia. Additionally, we examined the effect of animal grazing at four intensities (nil, light, moderate, and heavy) and explored the dynamic interconnections between PFTs and ecosystem services in grasslands. Our analysis revealed that the highest total ecosystem service and provisioning service were achieved under light- and moderate-grazing treatments, respectively. Heavy grazing also increased provisioning service but with a large decline in regulating and total ecosystem services. These changes in ESs were closely associated with grazing-induced variations in PFTs. Compared to no grazing, light grazing increased plant size-related functional traits, such as height, leaf length, leaf area, stem length, and the ratio of stem length to diameter. In contrast, heavy grazing decreased these PFTs. Provisioning and regulating services were determined by plant above-ground community function and structural properties, while supporting service was jointly affected by the below-ground community and soil properties. Our results indicate that light grazing should be recommended for the best total ESs, although moderate grazing may lead to high short-term economic benefits. Moreover, PFTs are powerful indicators for provisioning and regulating services. These findings provide a valuable reference for developing effective management practices to achieve targeted ESs using PFTs as indicators.


Assuntos
Ecossistema , Pradaria , Animais , Plantas , China , Herbivoria , Solo/química
17.
Plant Biotechnol J ; 20(6): 1054-1068, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35114063

RESUMO

The pollen wall exine provides a protective layer for the male gametophyte and is largely composed of sporopollenin, which comprises fatty acid derivatives and phenolics. However, the biochemical nature of the external exine is poorly understood. Here, we show that the male sterile line 1355A of cotton mutated in NO SPINE POLLEN (GhNSP) leads to defective exine formation. The GhNSP locus was identified through map-based cloning and confirmed by genetic analysis (co-segregation test and allele prediction using the CRISPR/Cas9 system). In situ hybridization showed that GhNSP is highly expressed in tapetum. GhNSP encodes a polygalacturonase protein homologous to AtQRT3, which suggests a function for polygalacturonase in pollen exine formation. These results indicate that GhNSP is functionally different from AtQRT3, the latter has the function of microspore separation. Biochemical analysis showed that the percentage of de-esterified pectin was significantly increased in the 1355A anthers at developmental stage 8. Furthermore, immunofluorescence studies using antibodies to the de-esterified and esterified homogalacturonan (JIM5 and JIM7) showed that the Ghnsp mutant exhibits abundant of de-esterified homogalacturonan in the tapetum and exine, coupled with defective exine formation. The characterization of GhNSP provides new understanding of the role of polygalacturonase and de-esterified homogalacturonan in pollen exine formation.


Assuntos
Regulação da Expressão Gênica de Plantas , Poligalacturonase , Fertilidade , Pectinas/metabolismo , Pólen/genética , Pólen/metabolismo , Poligalacturonase/genética , Poligalacturonase/metabolismo
18.
Neurochem Res ; 47(12): 3854-3862, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36331666

RESUMO

Eucalyptol (1.8-cineole), an active component in traditional Chinese medicine Artemisia argyi for moxibustion. Previous studies have shown that eucalyptol has anti-tumor effects on leukemia and colon cancer. Nonetheless, the effect and mechanism of eucalyptol on neuroblastoma remains unclear. In the present study, we intended to reveal the effect and mechanism of eucalyptol treatment on the neuroblastoma cell line SH-SY5Y through transcriptome analysis. In the group treated with eucalyptol, 566 brain genes were up-regulated, while 757 genes were down-regulated. GO function analysis showed that positive regulation of cell cycle was down-regulated in biological processes. Meanwhile, cancer-related pathways were identified in KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis, including pathways in cancer, PI3K-Akt signaling pathway, cAMP signaling pathway, TGF-beta signaling pathway, Hippo signaling pathway, p53 signaling pathway, and additional pathways. Furthermore, we found a key gene, such as MYC, by constructing a network of cancer related pathways with differentially expressed genes and transcription factor analysis. In conclusion, our research indicates that MYC might play a central role in the anit-tumor mechanisms of eucalyptol.


Assuntos
Neuroblastoma , Humanos , Neuroblastoma/tratamento farmacológico , Eucaliptol/farmacologia , Fosfatidilinositol 3-Quinases , Perfilação da Expressão Gênica , Linhagem Celular , Transcriptoma
19.
Wound Repair Regen ; 30(1): 34-44, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34826355

RESUMO

Wound healing may be disrupted by lipopolysaccharide (LPS)-induced mitochondrial dysfunction, inflammation, and excessive oxidative stress, which can lead to undesirable consequences. The haematopoietic cell-specific protein 1-associated protein X-1 (HAX-1) is a mitochondrial matrix protein that regulates mitochondrial function. This study aimed to comprehensively identify the role of HAX-1 in the inhibition of LPS-induced mitochondrial dysfunction and apoptosis in human dermal fibroblasts (HDFs). HAX-1 expression was assessed in the HDF-a cell line using real-time polymerase chain reaction, western blotting, and immunohistochemical staining. The viability, migration, and apoptosis of HDF-a cells were evaluated using the water-soluble tetrazolium-1 assay, transwell assay, and flow cytometry analysis, respectively. Mitochondrial function was evaluated based on reactive oxygen species (ROS) generation and mitochondrial membrane potential (ΔΨm). Our results demonstrated that LPS stimulation markedly repressed HAX-1 expression in HDFs and silencing of HAX-1 led to mitochondrial ROS accumulation, ΔΨm disruption, and abnormal mitochondrial morphology. Accordingly, overexpression of HAX-1 or administration of metformin enhanced mitochondrial fusion and normalized mitochondrial dynamics, thereby reversing LPS-induced mitochondrial dysfunction, fibroblast apoptosis, and viability and migration inhibition in HDF-a cells. These data support a mechanism wherein HAX-1 plays a crucial role in LPS-induced fibroblast apoptosis in a mitochondria-dependent manner.


Assuntos
Lipopolissacarídeos , Cicatrização , Apoptose , Fibroblastos , Humanos , Lipopolissacarídeos/farmacologia , Espécies Reativas de Oxigênio
20.
Bioorg Med Chem Lett ; 73: 128884, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35835377

RESUMO

11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) has been identified as the primary enzyme responsible for the activation of hepatic cortisone to cortisol in specific peripheral tissues, resulting in the concomitant antagonism of insulin action within these tissues. Dysregulation of 11ß-HSD1, particularly in adipose tissues, has been associated with a variety of ailments including metabolic syndrome and type 2 diabetes mellitus. Therefore, inhibition of 11ß-HSD1 with a small nonsteroidal molecule is therapeutically desirable. Implementation of a scaffold-hopping approach revealed a 3-point pharmacophore for 11ß-HSD1 that was utilized to design a 2-spiroproline derivative as a steroid mimetic scaffold. Reiterative optimization provided valuable insight into the bioactive conformation of our novel scaffold and led to the discovery of several leads, such as compounds 39 and 51. Importantly, deleterious hERG inhibition and pregnane X receptor induction were mitigated by the introduction of a 4-hydroxyl group to the proline ring system.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome Metabólica , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Hidrocortisona/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA