Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 853
Filtrar
1.
Br J Pharmacol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39001568

RESUMO

Diabetes mellitus is a long-term metabolic condition characterized by high blood glucose levels. This disorder is closely associated with a range of complications affecting small and large blood vessels, including conditions like retinopathy, nephropathy and neuropathy, as well as ischaemic heart disease, peripheral vascular disease and cerebrovascular disease. These complications cause organ and tissue damage in an estimated 33% to 50% of individuals with diabetes. The management of these complications in patients with diabetes is confronted with significant clinical challenges. Present treatment modalities for cardiovascular complications secondary to diabetes are limited and exhibit suboptimal efficacy. Cell-based therapies has shown great promise in regenerative medicine and improving cardiovascular function in individuals with diabetic complications, attributed to their potential for multilineage differentiation and regenerative capacity. In this review, we focus on diabetic cardiovascular complications and provide a brief introduction to the application of cell-based therapies, including the use of stem cells and progenitor cells, their mechanisms of action and the prospects and challenges.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39027976

RESUMO

Quercetin is kown for its antihypertensive effects. However, its role on hypertensive renal injury has not been fully eucidated. In this study, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) staining, and Annexin V staining were used to assess the pathological changes and cells apoptosis in the renal tissues of Ang II-infused mice and Ang II- stimulated renal tubular epithelial cell line (NRK-52E). A variety of technologies, including network pharmacology, RNA-sequencing, immunohistochemistry, and Western blotting were performed to investigate its underlying mechanisms. Network pharmacology analysis identified multiple potential candidate targets (including TP53, Bcl-2 and Bax) and enriched signaling pathways (including apoptosis and p53 signaling pathway). Quercetin treatment significantly alleviated the pathological changes in renal tissues of Ang II-infused mice and reversed 464 differentially expressed transcripts (DETs), as well as enriched several signaling pathways, including those related apoptosis and p53 pathway. Furthermore, quercetin treatment significantly inhibited the cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Additionally, quercetin treatment inhibited the upregulation of p53, Bax, cleaved-caspase-9, and cleaved-caspase-3 protein expression and the downregulation of Bcl-2 protein expression in both renal tissue of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Moreover, the molecular docking results indicated a potential binding interaction between quercetin and TP53. Quercetin treatment significantly attenuated hypertensive renal injury and cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells, and by targeting p53 may be one of the potential underlying mechanisms.

3.
Diabetes Obes Metab ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020261

RESUMO

AIM: The 2019 ESC/EASD guidelines categorize cardiovascular disease risk (CVD) in patients with diabetes mellitus (DM). Assessing CVD risk is necessary to identify individuals at very high risk of CVD, enabling tailored and precise intervention for this high-risk population. This study aims to evaluate the severity of a very high risk for CVD stratification among patients with type 2 DM (T2DM) across different regions in China. METHODS: We conducted a cross-sectional screening study from 1 January 2020 to 30 December 2022. Disease duration, body mass index (BMI), targeted organ damage, such as atherosclerotic heart disease, proteinuria, impaired renal function, left ventricular hypertrophy, retinopathy and known CVD risk factors, were collected from diabetic patients by professionally trained physicians. The risk of CV in patients with DM was categorized into two groups: very high risk and others, according to the 2019 ESC/EASD guidelines. RESULTS: In total, 1 870 720 participants from 1669 hospitals in 30 provinces of China, excluding Tibet, Taiwan, Hong Kong and Macao, were enrolled from 2020 to 2022, among whom 67.50% of patients with T2DM were at very high risk for CVD. The proportions of very high-risk T2DM were higher in Northeast China (75.82%), Central China (73.65%) and Southwest China (72.66%), while the lowest prevalence of very high-risk T2DM was found in Southern China (60.15%). The multivariate binary logistic regression analyses suggested that the category of very high risk for CVD is associated with age [odds ratio (OR) = 1.04; 95% confidence interval (CI): 1.04-1.04; p < .0001], BMI (OR = 1.07; 95% CI: 1.07-1.07; p < .0001), duration of DM (OR = 1.05; 95% CI: 1.05-1.05; p < .0001), hypertension (OR = 3.75; 95% CI: 3.72-3.78; p < .0001), dyslipidaemia (OR = 5.22; 95% CI: 5.18-5.27; p < .0001) and smoking (OR = 2.92; 95% CI: 2.89-2.95; p < .0001). CONCLUSIONS: This study represented the largest observational study of CVD risk assessment in patients with T2DM in China. The CVD risk situation of patients with diabetes in China is critical, and comprehensive control and management of CVD risk factors, such as hypertension, BMI and dyslipidaemia, in patients with DM need to be strengthened in patients with T2DM in China.

4.
J Agric Food Chem ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39021158

RESUMO

This study investigates how extracellular polymeric substances (EPS) synthesized by dark septate endophytic (DSE) improve alfalfa's drought resistance. Drought stress was simulated in hydroponic culture, and roots were treated with different EPS concentrations to determine their effects on drought tolerance and applicable concentrations. Hydroponic solutions with 0.25 and 0.50% EPS concentrations alleviated leaf wilting and increased total plant fresh weight by 35.8 and 57.7%, respectively. SEM shows that EPS attached to the roots and may have served to protect the root system. EPS treatment significantly depressed the MDA contents of the roots, stems, and leaves. Roots responded to drought stress by increasing soluble sugar contents and antioxidant enzyme activities, while mitigating stem and leaf stress by synthesizing lipid compounds, amino acids, and organic acid metabolites. Five metabolites in the stem have been reported to be associated with plant stress tolerance and growth, namely 3-O-methyl 5-O-(2-methyl propyl) (4S)-2,6-dimethyl-4-(2-nitrophenyl)-3,4-dihydropyridine-3,5-dicarboxylate, malic acid, PA (20:1(11Z)/15:0), N-methyl-4,6,7-trihydroxy-1,2,3,4-tetrahydroisoquinoline, and 2-(S-glutathionyl) acetyl glutathione. In summary, EPS treatment induced oxidative stress and altered plant metabolism, and this in turn increased plant antioxidant capacity. The results provide a theoretical basis for the application of EPS in commercial products that increase plant resistance and ecological restoration.

5.
Adv Sci (Weinh) ; : e2308890, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004913

RESUMO

Interferons (IFNs) activate JAK-STAT pathways to induce downstream effector genes for host defense against invaded pathogens and tumors. Here both type I (ß) and II (γ) IFNs are shown that can activate the transcription factor IRF3 in parallel with STAT1. IRF3-deficiency impairs transcription of a subset of downstream effector genes induced by IFN-ß and IFN-γ. Mechanistically, IFN-induced activation of IRF3 is dependent on the cGAS-STING-TBK1 axis. Both IFN-ß and IFN-γ cause mitochondrial DNA release into the cytosol. In addition, IFNs induce JAK1-mediated tyrosine phosphorylation of cGAS at Y214/Y215, which is essential for its DNA binding activity and signaling. Furthermore, deficiency of cGAS, STING, or IRF3 impairs IFN-ß- or IFN-γ-mediated antiviral and antitumor activities. The findings reveal a novel IRF3 activation pathway parallel with the canonical STAT1/2 activation pathways triggered by IFNs and provide an explanation for the pleiotropic roles of the cGAS-STING-IRF3 axis in host defense.

7.
ACS Nano ; 18(25): 16274-16284, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38867607

RESUMO

Integration of atomically thin nonlinear optical (NLO) devices demands an out-of-plane (OP) emission dipole of second harmonic generation (SHG) to enhance the spontaneous emission for nanophotonics. However, the research on van der Waals (vdWs) materials with an OP emission dipole of SHG is still in its infancy. Here, by coupling back focal plane (BFP) imaging with numerical simulations and density functional theory (DFT) calculations, we demonstrate that vdWs Janus Nb3SeI7, ranging from bulk to the monolayer limit, exhibits a dominant OP emission dipole of SHG owing to the breaking of the OP symmetry. Explicitly, even-layered Nb3SeI7 with C6v symmetry is predicted to exhibit a pure OP emission dipole attributed to the only second-order susceptibility coefficient χzxx. Meanwhile, although odd-layered Nb3SeI7 with C3v symmetry has both OP and IP dipole components (χzxx and χyyy), the value of χzxx is 1 order of magnitude greater than that of χyyy, leading to an approximate OP emission dipole of SHG. Moreover, the crystal symmetry and OP emission dipole can be preserved under hydrostatic pressure, accompanied by the enhanced χzxx and the resulting 3-fold increase in SHG intensity. The reported stable OP dipole in 2D vdWs Nb3SeI7 can facilitate the rapid development of chip-integrated NLO devices.

8.
Sensors (Basel) ; 24(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38894078

RESUMO

The paper presents a wide-bandwidth, low-polarization semiconductor optical amplifier (SOA) based on strained quantum wells. By enhancing the material gain of quantum wells for TM modes, we have extended the gain bandwidth of the SOA while reducing its polarization sensitivity. Through a combination of tilted waveguide design and cavity surface optical thin film design, we have effectively reduced the cavity surface reflectance of the SOA, thus decreasing device transmission losses and noise figure. At a wavelength of 1550 nm and a drive current of 1.4 A, the output power can reach 188 mW, with a small signal gain of 36.4 dB and a 3 dB gain bandwidth of 128 nm. The linewidth broadening is only 1.032 times. The polarization-dependent gain of the SOA is below 1.4 dB, and the noise figure is below 5.5 dB. The device employs only I-line lithography technology, offering simple fabrication processes and low costs yet delivering outstanding and stable performance. The designed SOA achieves wide gain bandwidth, high gain, low polarization sensitivity, low linewidth broadening, and low noise, promising significant applications in the wide-bandwidth optical communication field across the S + C + L bands.

9.
Tree Physiol ; 44(7)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38832722

RESUMO

Sabina chinensis is a typically heteromorphic leaf evergreen tree worldwide with both ornamental and ecological value. However, the shaping mechanism of heteromorphic leaves of S. chinensis and its adaptability to environment are important factors determining its morphology. The morphological change of S. chinensis under different habitats (tree around) and treatments (light, pruning and nutrients) was investigated. Our findings suggested that the prickle leaves proportion was associated with low light intensity and soil nutrient scarcity. Stems and leaves are pruned together to form clusters of large prickle leaves, while only pruning leaves often form alternately growing small prickle leaves and scale leaves, and the length of the prickle leaves is between 0.5 cm and 1 cm. The gene expression of prickle leaves is higher than that of scale leaves under adverse environmental conditions, and the gene expression correlations between small prickle leaf and scale leaf were the highest. Homologous and heterologous mutants of gene structure in prickle leaves were larger than those in scale leaves. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway showed that phenylpropanone and flavonoid biosynthesis were common enrichment pathways, and that the enrichment genes were mainly related to metabolism, genetic information processing and organismal systems. Therefore, we concluded that the occurrence of the heteromorphic leaf phenomenon was related to the changes in photosynthesis, mechanical damage and nutrient supplementation. The organic matter in the S. chinensis prickle leaves was reduced under environmental stresses, and it will be allocated to the expression of prickle leaf or protective cuticles formation.


Assuntos
Folhas de Planta , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Morfogênese , Adaptação Fisiológica , Ecossistema , Árvores/crescimento & desenvolvimento , Árvores/fisiologia , Regulação da Expressão Gênica de Plantas
10.
J Cancer Res Clin Oncol ; 150(6): 317, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914670

RESUMO

INTRODUCTION: CD24 is a highly glycosylated glycosylphosphatidylinositol anchored membrane protein that plays an important role in tumor progression. The aim of this study was to investigate the effect of abnormal expression of CD24 on the proliferation, migration and invasion of breast cancer (BC) cells, and the molecular mechanism of regulating CD24 expression in breast cancer. METHODOLOGY: The bioinformatics method was used to predict the expression level of CD24 in BC and its relationship with the occurrence and development of BC. IHC, RT-qPCR and WB were used to detect the expression of CD24 in BC tissues and cells. The proliferation of CD24 was evaluated by CCK-8 and colony formation assay, and the migration and invasion of CD24 were evaluated by wound healing and transwell. In addition, the effect of CD24 on the malignancy of BC in vivo was further evaluated by subcutaneous tumorigenesis assay. Molecular mechanisms were measured by luciferase reporter assays, biotin-labeled miRNA pull-down assay, RIP, and western blotting. RESULTS: The results show that CD24 is highly expressed in breast cancer tissues and cell lines, and knockdown of CD24 in vivo and in vitro can inhibit the proliferation, migration and invasion of BC cells. Mechanistically, the transcription factor ZNF460 promotes its expression by binding to the CD24 promoter, and the expression of ZNF460 is regulated by miR-125a-5p, which inhibits its expression by targeting the 3'UTR of ZNF460. In addition, LINC00525 acts as a ceRNA sponge to adsorb miR-125a-5p and regulate its expression. CONCLUSIONS: Overexpression of CD24 is involved in the development and poor prognosis of BC, which can be used as a potential target for the treatment of BC and provide a theoretical basis for the treatment of BC.


Assuntos
Neoplasias da Mama , Antígeno CD24 , Proliferação de Células , Progressão da Doença , MicroRNAs , RNA Longo não Codificante , Humanos , Antígeno CD24/genética , Antígeno CD24/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , MicroRNAs/genética , Animais , Camundongos , RNA Longo não Codificante/genética , Camundongos Nus , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Movimento Celular/genética , Camundongos Endogâmicos BALB C , Prognóstico
11.
Transl Oncol ; 46: 102000, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38852278

RESUMO

Gastric cancer (GC) has become the first malignant tumor with highest incidence rate and mortality of cancer in China, finding therapeutic targets for gastric cancer is of great significant for improving the survival rate of patients with GC. Recently, many of studies have shown that LncRNAs is involved in multiple biological progresses in the development of GC. This study, we screened for abnormally high expression of LncSHANK3 in GC through the TCGA database, and found that LncSHANK3 sponge adsorbs miR-4530, further competing with MNX1 and binding to miR-4530. We demonstrated the interaction between LncSHANK3 and miR-4530 through luciferase reporting analysis, with miR-4530 negatively regulating MNX1.Through CCK8, colony formation, transwell, and wound healing assays, it was found that LncSHANK3 affects the occurrence of GC through cell proliferation, migration and invasion. In conclusion, LncSHANK3/miR-4530/MNX1 axis is a potential mechanism for the treatment of GC.

12.
Fish Shellfish Immunol ; 152: 109726, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944254

RESUMO

The immune system of bony fish closely resembles that of mammals, comprising both specific (adaptive) and non-specific (innate) components. Notably, the mucosa-associated lymphoid tissue (MALT) serves as the first line of defense within the non-specific immune system, playing a critical role in protecting these aquatic organisms against invading pathogens. MALT encompasses a network of immune cells strategically distributed throughout the gills and intestines, forming an integral part of the mucosal barrier that interfaces directly with the surrounding aquatic environment. Spring Viremia of Carp Virus(SVCV), a highly pathogenic agent causing substantial harm to common carp populations, has been designated as a Class 2 animal disease by the Ministry of Agriculture and Rural Affairs of China. Utilizing a comprehensive array of research techniques, including Hematoxylin and Eosin (HE)、Alcian Blue Periodic Acid-Schiff (AB-PAS)、transcriptome analysis for global gene expression profiling and Reverse Transcription-Polymerase Chain Reaction (RT-qPCR), this study uncovered several key findings: SVCV is capable of compromising the mucosal architecture in the gill and intestinal tissues of carp, and stimulate the proliferation of mucous cells both in gill and intestinal tissues. Critically, the study revealed that SVCV's invasion elicits a robust response from the carp's mucosal immune system, demonstrating the organism's capacity to resist SVCV invasion despite the challenges posed by the pathogen.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38862430

RESUMO

Tandem duplication (TD) is a major type of structural variations (SVs) that plays an important role in novel gene formation and human diseases. However, TDs are often missed or incorrectly classified as insertions by most modern SV detection methods due to the lack of specialized operation on TD-related mutational signals. Herein, we developed a TD detection module for the Pindel tool, referred to as Pindel-TD, based on a TD-specific pattern growth approach. Pindel-TD is capable of detecting TDs with a wide size range at single nucleotide resolution. Using simulated and real read data from HG002, we demonstrated that Pindel-TD outperforms other leading methods in terms of precision, recall, F1-score, and robustness. Furthermore, by applying Pindel-TD to data generated from the K562 cancer cell line, we identified a TD located at the seventh exon of SAGE1, providing an explanation for its high expression. Pindel-TD is available for non-commercial use at https://github.com/xjtu-omics/pindel.


Assuntos
Software , Humanos , Células K562 , Duplicação Gênica , Sequências de Repetição em Tandem/genética , Algoritmos
14.
Lancet Reg Health West Pac ; 47: 101100, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38881803

RESUMO

Background: Long-term exposure to PM2.5 is known to increase the risks for diabetes and obesity, but its effects on their coexistence, termed diabesity, remain uncertain. This study aimed to investigate the associations of long-term exposure to PM2.5 and its chemical constituents with the risks for diabesity, diabetes, and obesity. Methods: This cross-sectional study used the baseline data of a multi-center cohort, consisting of three provincially representative cohorts comprising a total of 134,403 participants from the eastern (Fujian Province), central (Hubei Province), and western (Yunnan Province) regions of China. Obesity and diabetes, and diabesity were identified by a body mass index (BMI) ≥28 kg/m2 and fasting plasma glucose (FPG) ≥126 mg/dL. The average concentrations of PM2.5 and five chemical constituents (NO3 -, SO4 2-, NH4 +, organic matter, and black carbon) over participants' residence during the past three years were estimated using machine learning models. Logistic regression models with double robust estimators, Bayesian kernel machine regression, and weighted quantile sum regression were employed to estimate independent and joint effects of PM2.5 chemical constituents on the risks for diabesity, diabetes, and obesity, as well as the differences from the effects on obesity. Stratified analyses were performed to examine effect modification of sociodemographic and lifestyle factors. Findings: There were 129,244 participants with a mean age of 54.1 ± 13.8 years included in the study. Each interquartile range increase in PM2.5 concentration (8.53 µg/m3) was associated with an increased risk for diabesity (OR = 1.23 [1.17, 1.30]), diabetes only (OR = 1.16 [1.13, 1.19]), and obesity only (OR = 1.03 [1.00, 1.05]). Long-term exposure to each PM2.5 chemical constituent was associated with an increased risk for diabesity, where organic matter exposure, with maximum weight (48%), was associated with a higher risk for diabesity (OR = 1.21 [1.16, 1.27]). Among those with obesity, black carbon contributed most (68%) to the joint effect of PM2.5 chemical constituents on diabesity (OR = 1.16 [1.11, 1.22]). Physical activity reduced adverse effects of PM2.5 on diabesity. Also, additive rather than multiplicative effects of obesity on the PM2.5-diabetes association were observed. Interpretation: Long-term exposure to PM2.5 and its chemical constituents was associated with an increased risk for diabesity, stronger than associations for diabetes and obesity alone. The main constituents associated with diabesity and obesity were black carbon and organic matter. Funding: National Natural Science Foundation of China (42271433, 723B2017), National Key R&D Program of China (2023YFC3604702), Fundamental Research Funds for the Central Universities (2042023kfyq04, 2042024kf1024), the Science and Technology Major Project of Tibetan Autonomous Region of China (XZ202201ZD0001G), Science and technology project of Tibet Autonomous Region(XZ202303ZY0007G), Key R&D Project of Sichuan Province (2023YFS0251), Renmin Hospital of Wuhan University (JCRCYG-2022-003), Jiangxi Provincial 03 Special Foundation and 5G Program (20224ABC03A05), Wuhan University Specific Fund for Major School-level Internationalization Initiatives (WHU-GJZDZX-PT07).

15.
Natl Sci Rev ; 11(7): nwae177, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38883289

RESUMO

Covalent-organic frameworks (COFs) with photoinduced donor-acceptor (D-A) radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining [6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine (PTZ) show superior photocatalytic production rates of hydrogen peroxide (H2O2). Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2O2 synthesis rate of 3324 µmol g-1 h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2O2 production. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.

16.
Am J Transl Res ; 16(5): 1740-1748, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883341

RESUMO

OBJECTIVE: To identify factors influencing recurrence after percutaneous transhepatic choledochoscopic lithotripsy (PTCSL) and to develop a predictive model. METHODS: We retrospectively analyzed clinical data from 354 patients with intrahepatic and extrahepatic bile duct stones treated with PTCSL at Qinzhou First People's Hospital between February 2018 and January 2020. Patients were followed for three years and categorized into non-recurrence and recurrence groups based on postoperative outcome. Univariate analysis identified possible predictors of stone recurrence. Data were split using the gradient boosting machine (GBM) algorithm, assigning 70% as the training set and 30% as the test set. The predictive performance of the GBM model was assessed using the receiver operating characteristic (ROC) curve and calibration curve, and compared with a logistic regression model. RESULTS: Six factors were identified as significant predictors of recurrence: age, diabetes, total bilirubin, biliary stricture, number of stones, and stone diameter. The GBM model, developed based on these factors, showed high predictive accuracy. The area under the ROC curve (AUC) was 0.763 (95% CI: 0.695-0.830) for the training set and 0.709 (95% CI: 0.596-0.822) for the test set. Optimal cutoff values were 0.286 and 0.264, with sensitivities of 62.30% and 66.70%, and specificities of 77.20% and 68.50%, respectively. Calibration curves indicated good agreement between predicted probabilities and observed recurrence rates in both sets. DeLong's test revealed no significant differences between the GBM and logistic regression models in predictive performance (training set: D = 0.003, P = 0.997 > 0.05; test set: D = 0.075, P = 0.940 > 0.05). CONCLUSION: Biliary stricture, stone diameter, diabetes, stone number, age, and total bilirubin significantly influence stone recurrence after PTCSL. The GBM model, based on these factors, demonstrates robust accuracy and discrimination. Both GBM and logistic regression models effectively predicted stone recurrence post-PTCSL.

17.
Nanomaterials (Basel) ; 14(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38869594

RESUMO

Polarization-insensitive semiconductor optical amplifiers (SOAs) in all-optical networks can improve the signal-light quality and transmission rate. Herein, to reduce the gain sensitivity to polarization, a multi-quantum-well SOA in the 1550 nm band is designed, simulated, and developed. The active region mainly comprises the quaternary compound InGaAlAs, as differences in the potential barriers and wells of the components cause lattice mismatch. Consequently, a strained quantum well is generated, providing the SOA with gain insensitivity to the polarization state of light. In simulations, the SOA with ridge widths of 4 µm, 5 µm, and 6 µm is investigated. A 3 dB gain bandwidth of >140 nm is achieved with a 4 µm ridge width, whereas a 6 µm ridge width provides more output power and gain. The saturated output power is 150 mW (21.76 dB gain) at an input power of 0 dBm but increases to 233 mW (13.67 dB gain) at an input power of 10 dBm. The polarization sensitivity is <3 dBm at -20 dBm. This design, which achieves low polarization sensitivity, a wide gain bandwidth, and high gain, will be applicable in a wide range of fields following further optimization.

18.
Front Endocrinol (Lausanne) ; 15: 1397402, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38872962

RESUMO

Graphene-based warm uterus acupoint paste (GWUAP) is an emerging non-drug alternative therapy for the treatment of primary dysmenorrhea (PD), but the underlying mechanism is still unclear. SD female rats were randomly divided into control group, model group and treatment group to explore the mechanism of GWUAP in the treatment of PD. Combined with 16S rDNA and fecal metabolomics, the diversity of microbiota and metabolites in each group was comprehensively evaluated. In this study, GWUAP reduced the torsion score of PD model rats, improved the pathological morphology of uterine tissue, reduced the pathological damage score of uterine tissue, and reversed the expression levels of inflammatory factors, pain factors and sex hormones. The 16 S rDNA sequencing of fecal samples showed that the abundance of Lactobacillus in the intestinal flora of the model group decreased and the abundance of Romboutsia increased, while the abundance of Lactobacillus in the intestinal flora of the treatment group increased and the abundance of Romboutsia decreased, which improved the imbalance of flora diversity in PD rats. In addition, 32 metabolites related to therapeutic effects were identified by metabolomics of fecal samples. Moreover, there is a close correlation between fecal microbiota and metabolites. Therefore, the mechanism of GWUAP in the treatment of PD remains to be further studied.


Assuntos
Pontos de Acupuntura , Dismenorreia , Metabolômica , Ratos Sprague-Dawley , Animais , Feminino , Dismenorreia/terapia , Dismenorreia/tratamento farmacológico , Ratos , Microbioma Gastrointestinal/efeitos dos fármacos , RNA Ribossômico 16S/genética , Fezes/microbiologia , DNA Ribossômico/genética
19.
ACS Nano ; 18(26): 17053-17064, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38870206

RESUMO

Second harmonic generation (SHG) in van der Waals (vdW) materials has garnered significant attention due to its potential for integrated nonlinear optical and optoelectronic applications. Stacking faults in vdW materials are a typical kind of planar defect that introduces a degree of freedom to modulate the crystal symmetry and resultant SHG response. However, the physical origin and tunability of stacking-fault-governed SHG in vdW materials remain unclear. Here, taking the intrinsically centrosymmetric vdW RhI3 as an example, we theoretically reveal the origin of stacking-fault-governed SHG response, where the SHG response comes from the energetically favorable AC̅ stacking fault of which the electrical transitions along the high-symmetry paths Γ-M and Γ-K in the Brillion zone play the dominant role at 810 nm. Such a stacking-fault-governed SHG response is further confirmed via structural characterizations and SHG measurements. Furthermore, by applying hydrostatic pressure on RhI3, the correlation between structural evolution and SHG response is revealed with SHG enhancement up to 6.9 times, where the decreased electronic transition energies and higher momentum matrix elements due to the stronger interlayer interactions upon compression magnify the SHG susceptibility. This study develops a promising foundation for nonlinear nano-optics applications through the strategic design of stacking faults.

20.
Plant Physiol Biochem ; 212: 108707, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763002

RESUMO

Apple (Malus domestica Borkh.) is a widely cultivated fruit crop worldwide but often suffers from abiotic stresses such as salt and cold. Gibberellic acid (GA) plays a pivotal in controlling plant development, environmental adaptability, and secondary metabolism. The GA2-oxidase (GA2ox) is responsible for the deactivation of bioactive GA. In this study, seventeen GA2-oxidase genes were identified in the apple genome, and these members could be clustered into four clades based on phylogenetic relationships and conserved domain structures. MdGA2ox7 exhibited robust expression across various tissues, responded to cold and salt treatments, and was triggered in apple fruit peels via light-induced anthocyanin accumulation. Subcellular localization prediction and experiments confirmed that MdGA2ox7 was located in the cytoplasm. Overexpression of MdGA2ox7 in Arabidopsis caused a lower level of active GA and led to GA-deficient phenotypes, such as dwarfism and delayed flowering. MdGA2ox7 alleviated cold and salt stress damage in both Arabidopsis and apple in concert with melatonin (MT). Additionally, MdGA2ox7 enhanced anthocyanin biosynthesis in apple calli and activated genes involved in anthocyanin synthesis. These findings provide new insights into the functions of apple GA2ox in regulating development, stress tolerance, and secondary metabolism.


Assuntos
Antocianinas , Regulação da Expressão Gênica de Plantas , Malus , Proteínas de Plantas , Malus/genética , Malus/metabolismo , Antocianinas/metabolismo , Antocianinas/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Fisiológico , Arabidopsis/genética , Arabidopsis/metabolismo , Giberelinas/metabolismo , Filogenia , Plantas Geneticamente Modificadas , Melatonina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...