Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 318
1.
Alzheimers Res Ther ; 16(1): 103, 2024 May 10.
Article En | MEDLINE | ID: mdl-38725083

BACKGROUND: The role of α-synuclein in dementia has been recognized, yet its exact influence on cognitive decline in non-demented older adults is still not fully understood. METHODS: A total of 331 non-demented individuals were included in the study from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Participants were divided into two distinct groups based on their α-synuclein levels: one with lower levels (α-synuclein-L) and another with higher levels (α-synuclein-H). Measurements included neuropsychiatric scales, cerebrospinal fluid (CSF) biomarkers, and blood transcriptomics. The linear mixed-effects model investigated the longitudinal changes in cognition. Kaplan-Meier survival analysis and the Cox proportional hazards model were utilized to evaluate the effects of different levels of α-synuclein on dementia. Gene set enrichment analysis (GSEA) was utilized to investigate the biological pathways related to cognitive impairment. Pearson correlation, multiple linear regression models, and mediation analysis were employed to investigate the relationship between α-synuclein and neurodegenerative biomarkers, and their potential mechanisms affecting cognition. RESULTS: Higher CSF α-synuclein levels were associated with increased risk of cognitive decline and progression to dementia. Enrichment analysis highlighted the activation of tau-associated and immune response pathways in the α-synuclein-H group. Further correlation and regression analysis indicated that the CSF α-synuclein levels were positively correlated with CSF total tau (t-tau), phosphorylated tau (p-tau) 181, tumor necrosis factor receptor 1 (TNFR1) and intercellular cell adhesion molecule-1 (ICAM-1). Mediation analysis further elucidated that the detrimental effects of CSF α-synuclein on cognition were primarily mediated through CSF t-tau and p-tau. Additionally, it was observed that CSF α-synuclein influenced CSF t-tau and p-tau181 levels via inflammatory pathways involving CSF TNFR1 and ICAM-1. CONCLUSIONS: These findings elucidate a significant connection between elevated levels of CSF α-synuclein and the progression of cognitive decline, highlighting the critical roles of activated inflammatory pathways and tau pathology in this association. They underscore the importance of monitoring CSF α-synuclein levels as a promising biomarker for identifying individuals at increased risk of cognitive deterioration and developing dementia.


Biomarkers , Cognitive Dysfunction , alpha-Synuclein , tau Proteins , Humans , Female , Male , Cognitive Dysfunction/cerebrospinal fluid , alpha-Synuclein/cerebrospinal fluid , Aged , tau Proteins/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Biomarkers/blood , Aged, 80 and over , Neuropsychological Tests
2.
Article En | MEDLINE | ID: mdl-38735531

OBJECTIVES: To investigate the clinical and molecular epidemiological characteristics of blaIMP-4-carrying Klebsiella pneumoniae in a tertiary hospital in China. METHODS: 10 Carbapenem Resistant K. pneumoniae (CRKP) isolates with blaIMP-4 gene were collected. Molecular characteristics were analyzed using whole-genome sequencing. Plasmid conjugation experiment was used to analyze the conjugation of plasmids. We compared and analyzed K. pneumoniae carrying blaIMP-4 on NCBI with the strains in this study. RESULTS: All 10 CRKP isolates with blaIMP-4 were collected from 10 adult patients in the respiratory intensive care unit. These strains were only sensitive to polymyxins and tigecycline due to simultaneously carrying multiple resistance genes, such as blaOKP-A-5, fosA, oqxA and oqxB. Notably, R29 harbored two carbapenemase genes (blaNDM-1 and blaIMP-4). These strains had similar drug-resistant phenotypes and drug-resistant genes, all belonging to ST196. Additionally, the patients had spatiotemporal intersection during hospitalization, suggesting that these strains had clonal transmission, but they belonged to different clonal clusters from the blaIMP-4-positive K. pneumoniae currently published on NCBI. Among the 10 strains, blaIMP-4 was located on the IncN plasmid, and 6 strains had successfully transferred the plasmid to the recipient strain EC600 through plasmid conjugation. CONCLUSIONS: The blaIMP-4-positive ST196 CRKP had clonal distribution in the respiratory ICU, which was mediated by IncN plasmid. Consequently, there should be increased monitoring of carbapenem-resistant strains in clinical settings to prevent and control of its transmission.

3.
J Anim Sci ; 2024 May 07.
Article En | MEDLINE | ID: mdl-38713167

Follicular fluid meiosis-activating sterol (FF-MAS) is a small molecule compound found in follicular fluid, named for its ability to induce oocyte resumption of meiosis. Granulosa cells (GCs) within the follicle are typically located in a hypoxic environment under physiologic conditions due to limited vascular distribution. Previous research suggests that hypoxia-induced cell cycle arrest and apoptosis in GCs may be crucial triggering factors in porcine follicular atresia. However, the impact of FF-MAS on GCs within follicles has not been explored so far. In this study, we uncovered a novel role of FF-MAS in facilitating GC survival under hypoxic conditions by inhibiting STAT4 expression. We found that STAT4 expression was upregulated in porcine GCs exposed to 1% O2. Both gain and loss of function assays confirmed that STAT4 was required for cell apoptosis under hypoxia conditions, and that the GC apoptosis caused by hypoxia was markedly attenuated following FF-MAS treatment through inhibition of STAT4 expression. Correlation analysis in vivo revealed that GC apoptosis was associated with increased STAT4 expression, while the FF-MAS content in follicular fluid was negatively correlated with STAT4 mRNA levels and cell apoptosis. These findings elucidate a novel role of FF-MAS-mediated protection of GCs by inhibiting STAT4 expression under hypoxia, which might contribute to the mechanistic understanding of follicular development.

4.
Nanoscale ; 2024 Apr 17.
Article En | MEDLINE | ID: mdl-38629471

The utilization of Microelectromechanical Systems (MEMS) technology holds great significance for developing compact and high-performance humidity sensors in human healthcare, and the Internet of Things. However, several drawbacks of the current MEMS humidity sensors limit their applications, including their long response time, low sensitivity, relatively large sensing area, and incompatibility with a complementary metal-oxide-semiconductor (CMOS) process. To address these problems, a suspended aluminum scandium nitride (AlScN) Lamb wave humidity sensor utilizing a graphene oxide (GO) layer is firstly designed and fabricated. The theoretical and experimental results both show that the AlScN Lamb wave humidity sensor exhibits high sensing performance. The mass loading sensitivity of the sensor is one order higher than that of the normal surface acoustic wave (SAW) humidity sensor based on an aluminum nitride (AlN) film; thus the AlScN Lamb wave humidity sensor achieves high sensitivity (∼41.2 ppm per % RH) with only an 80 nm-thick GO film. In particular, the as-prepared suspended AlScN Lamb wave sensors are able to respond to the wide relative humidity (0-80% RH) change in 2 s, and the device size is ultra-compact (260 µm × 72 µm). Moreover, the sensor has an excellent linear response in the 0-80% RH range, great repeatability and long-term stability. Therefore, this work brings opportunities for the development of ultra-compact and high-performance humidity sensors.

5.
Chin Med J (Engl) ; 137(8): 980-989, 2024 Apr 20.
Article En | MEDLINE | ID: mdl-38445358

BACKGROUND: Somatic copy number variations (SCNVs) in the CDKN2A gene are among the most frequent events in the dysplasia-carcinoma sequence of esophageal squamous cell carcinoma. However, whether CDKN2A SCNVs are useful biomarkers for the risk stratification and management of patients with esophageal squamous cell dysplasia (ESCdys) is unknown. This study aimed to investigate the characteristics and prognostic value of CDKN2A SCNVs in patients with mild or moderate (m/M) ESCdys. METHODS: This study conducted a prospective multicenter study of 205 patients with a baseline diagnosis of m/M ESCdys in five high-risk regions of China (Ci County, Hebei Province; Yanting, Sichuan Province; Linzhou, Henan Province; Yangzhong, Jiangsu Province; and Feicheng, Shandong Province) from 2005 to 2019. Genomic DNA was extracted from paraffin biopsy samples and paired peripheral white blood cells from patients, and a quantitative polymerase chain reaction assay, P16-Light, was used to detect CDKN2A copy number. The cumulative regression and progression rates of ESCdys were evaluated using competing risk models. RESULTS: A total of 205 patients with baseline m/M ESCdys were enrolled. The proportion of ESCdys regression was significantly lower in the CDKN2A deletion cohort than in the diploid and amplification cohorts (18.8% [13/69] vs. 35.0% [28/80] vs. 51.8% [29/56], P  <0.001). In the univariable competing risk analysis, the cumulative regression rate was statistically significantly lower ( P = 0.008), while the cumulative progression rate was higher ( P = 0.017) in ESCdys patients with CDKN2A deletion than in those without CDKN2A deletion. CDKN2A deletion was also an independent predictor of prognosis in ESCdys ( P = 0.004) in the multivariable analysis. CONCLUSION: The results indicated that CDKN2A SCNVs are associated with the prognosis of ESCdys and may serve as potential biomarkers for risk stratification.


Cyclin-Dependent Kinase Inhibitor p16 , DNA Copy Number Variations , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , DNA Copy Number Variations/genetics , Female , Male , Middle Aged , Esophageal Neoplasms/genetics , Esophageal Neoplasms/pathology , Cyclin-Dependent Kinase Inhibitor p16/genetics , Esophageal Squamous Cell Carcinoma/genetics , Esophageal Squamous Cell Carcinoma/pathology , Prospective Studies , Prognosis , Aged , Adult
6.
J Med Chem ; 67(7): 5502-5537, 2024 Apr 11.
Article En | MEDLINE | ID: mdl-38552183

Patients with arterial embolic disease have benefited greatly from antiplatelet therapy. However, hemorrhage risk of antiplatelet agents cannot be ignored. Herein, we describe the discovery of 2,3-dihydro[1,4]dioxino[2,3-g]benzofuran compounds as novel PAR4 antagonists. Notably, the isomers 36 and 37 with the chemotype of phenoxyl methylene substituted on the 2,3-dihydro-1,4-dioxine ring exhibited potent in vitro antiplatelet activity (IC50 = 26.13 nM for 36 and 14.26 nM for 37) and significantly improved metabolic stability in human liver microsomes (T1/2 = 97.6 min for 36 and 11.1 min for BMS-986120). 36 also displayed good oral PK profiles (mice: T1/2 = 7.32 h and F = 45.11%). Both of them showed overall potent ex vivo antiplatelet activity at concentrations of 6 and 12 mg/kg, with no impact on the coagulation system and low bleeding liability. Our work will facilitate development of novel PAR4 antagonists as a safer therapeutic option for arterial embolism.


Benzofurans , Thrombosis , Humans , Mice , Animals , Receptors, Thrombin , Platelet Aggregation Inhibitors/metabolism , Hemorrhage/chemically induced , Hemorrhage/drug therapy , Hemorrhage/metabolism , Blood Coagulation , Thrombosis/drug therapy , Benzofurans/therapeutic use , Platelet Aggregation , Receptor, PAR-1/metabolism , Receptor, PAR-1/therapeutic use , Blood Platelets/metabolism
7.
Heliyon ; 10(4): e26229, 2024 Feb 29.
Article En | MEDLINE | ID: mdl-38420423

Infrared ship detection is of great significance due to its broad applicability in maritime surveillance, traffic safety and security. Multiple infrared sensors with different spectral sensitivity provide enhanced sensing capabilities, facilitating ship detection in complex environments. Nevertheless, current researches lack discussion and exploration of infrared imagers in different spectral ranges for marine objects detection. Furthermore, for unmanned marine vehicles (UMVs), e.g., unmanned surface vehicles (USVs) and unmanned ship (USs), detection and perception are usually performed in embedded devices with limited memory and computation resource, which makes traditional convolutional neural network (CNN)-based detection methods struggle to leverage their advantages. Aimed at the task of sea surface object detection on USVs, this paper provides lightweight CNNs with high inference speed that can be deployed on embedded devices. It also discusses the advantages and disadvantages of using different sensors in marine object detection, providing a reference for the perception and decision-making modules of USVs. The proposed method can detect ships in short-wave infrared (SWIR), long-wave infrared (LWIR) and fused images with high-performance and high-inference speed on an embedded device. Specifically, the backbone is built from bottleneck depth-separable convolution with residuals. Generating redundant feature maps by using cheap linear operation in neck and head networks. The learning and representation capacities of the network are promoted by introducing the channel and spatial attention, redesigning the sizes of anchor boxes. Comparative experiments are conducted on the infrared ship dataset that we have released which contains SWIR, LWIR and the fused images. The results indicate that the proposed method can achieve high accuracy but with fewer parameters, and the inference speed is nearly 60 frames per second (FPS) on an embedded device.

8.
bioRxiv ; 2024 Feb 05.
Article En | MEDLINE | ID: mdl-38370711

Stem cell therapy holds significant potential for many inflammatory diseases and regenerative medicine applications. However, delivery of therapeutic cells to specific disease sites after systemic administration without indiscriminate trafficking to other non-target tissues is a major limitation of current cell therapies. Here, we describe a novel nanocarrier-directed targeted cell delivery system that enables cell surface coating with dendrimer nanocarriers containing adhesion moieties to serve as a global positioning system "GPS" to guide circulating cells to targeted lesions and mediate the anchoring of cells at the inflammation site. By exploiting cell surface ligands/receptors selectively and/or molecular moieties that are highly expressed on activated endothelium in pathologic disease states, nanocarrier-coated cells containing the counterpart binding receptors/ligands can be enabled to specifically traffic to and dock at vasculature within target lesions. We demonstrate the efficacy of the I-domain fragment of LFA-1 ( id LFA-1) complexed to modified nanocarriers to facilitate homing of mesenchymal stem cells (MSCs) to inflamed luminal endothelial cells on which ICAM-1 is highly expressed in a murine model of aortic atherosclerosis. Our method can overcome challenges imposed by the high velocity and dynamic circulatory flow of the aorta to successfully deliver MSCs to atherosclerotic regions and allow for docking of the potentially therapeutic and immunomodulating cells. This targeted cell-delivery platform can be tailored for selective systemic delivery of various types of therapeutic cells to different disease areas.

9.
Int J Mol Sci ; 25(4)2024 Feb 11.
Article En | MEDLINE | ID: mdl-38396848

Fibroblasts are stromal cells ubiquitously distributed in the body of nearly every organ tissue. These cells were previously considered to be "passive cells", solely responsible for ensuring the turnover of the extracellular matrix (ECM). However, their versatility, including their ability to switch phenotypes in response to tissue injury and dynamic activity in the maintenance of tissue specific homeostasis and integrity have been recently revealed by the innovation of technological tools such as genetically modified mouse models and single cell analysis. These highly plastic and heterogeneous cells equipped with multifaceted functions including the regulation of angiogenesis, inflammation as well as their innate stemness characteristics, play a central role in the delicately regulated process of wound healing. Fibroblast dysregulation underlies many chronic conditions, including cardiovascular diseases, cancer, inflammatory diseases, and diabetes mellitus (DM), which represent the current major causes of morbidity and mortality worldwide. Diabetic foot ulcer (DFU), one of the most severe complications of DM affects 40 to 60 million people. Chronic non-healing DFU wounds expose patients to substantial sequelae including infections, gangrene, amputation, and death. A complete understanding of the pathophysiology of DFU and targeting pathways involved in the dysregulation of fibroblasts are required for the development of innovative new therapeutic treatments, critically needed for these patients.


Diabetes Mellitus , Diabetic Foot , Animals , Mice , Humans , Diabetic Foot/therapy , Fibroblasts/metabolism , Extracellular Matrix/metabolism , Chronic Disease , Disease Progression , Diabetes Mellitus/metabolism
10.
Opt Lett ; 49(4): 891-894, 2024 Feb 15.
Article En | MEDLINE | ID: mdl-38359209

A high-power all-fiber radially polarized laser system is demonstrated, in which an integrated nanograting mode convertor (S-wave plate) is used for the generation of radially polarized beam. Experimentally, a 1-W radially polarized beam was used as the seed laser, whose mode purity and mode extinction ratio (MER) were 96.5% and 98.3%, respectively. A single-stage few-mode fiber amplifier was employed to boost the 1-W seed laser to an average power of 113.2 W, when the pump power was 160 W. The corresponding slope efficiency and beam quality factor (M2) were approximately 72% and 2.3%, respectively. Moreover, the mode purity and MER of the amplified radially polarized laser were measured to be 95.7% and 97%, respectively. To the best of our knowledge, this is the highest output power from an all-fiber radially polarized laser system without obvious degradations of the mode purity and MER.

11.
Ann Clin Microbiol Antimicrob ; 23(1): 13, 2024 Feb 12.
Article En | MEDLINE | ID: mdl-38347529

BACKGROUND: Recently, extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) isolates have been increasingly detected and posed great challenges to clinical anti-infection treatments. However, little is known about extensively resistant hypervirulent P. aeruginosa (XDR-hvPA). In this study, we investigate its epidemiological characteristics and provide important basis for preventing its dissemination. METHODS: Clinical XDR-PA isolates were collected from January 2018 to January 2023 and identified using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry; antibiotic susceptibility testing was performed by broth microdilution method, and minimum inhibitory concentrations (MICs) were evaluated. Virulence was evaluated using the Galleria mellonella infection model; molecular characteristics, including resistance genes, virulence genes, and homology, were determined using whole-genome sequencing. RESULTS: A total of 77 XDR-PA strains were collected; 47/77 strains were XDR-hvPA. Patients aged > 60 years showed a significantly higher detection rate of XDR-hvPA than of XDR-non-hvPA. Among the 47 XDR-hvPA strains, 24 strains carried a carbapenemase gene, including blaGES-1 (10/47), blaVIM-2 (6/47), blaGES-14 (4/47), blaIMP-45 (2/47), blaKPC-2 (1/47), and blaNDM-14 (1/47). ExoU, exoT, exoY, and exoS, important virulence factors of PA, were found in 31/47, 47/47, 46/47, and 29/47 strains, respectively. Notably, two XDR-hvPA simultaneously co-carried exoU and exoS. Six serotypes (O1, O4-O7, and O11) were detected; O11 (19/47), O7 (13/47), and O4 (9/47) were the most prevalent. In 2018-2020, O4 and O7 were the most prevalent serotypes; 2021 onward, O11 (16/26) was the most prevalent serotype. Fourteen types of ST were detected, mainly ST235 (14/47), ST1158 (13/47), and ST1800 (7/47). Five global epidemic ST235 XDR-hvPA carried blaGES and showed the MIC value of ceftazidime/avibactam reached the susceptibility breakpoint (8/4 mg/L). CONCLUSIONS: The clinical detection rate of XDR-hvPA is unexpectedly high, particularly in patients aged > 60 years, who are seemingly more susceptible to contracting this infection. Clonal transmission of XDR-hvPA carrying blaGES, which belongs to the global epidemic ST235, was noted. Therefore, the monitoring of XDR-hvPA should be strengthened, particularly for elderly hospitalized patients, to prevent its spread.


Anti-Bacterial Agents , Pseudomonas Infections , Aged , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Pseudomonas aeruginosa/genetics , Pseudomonas Infections/epidemiology , Pseudomonas Infections/drug therapy , Bacterial Proteins/genetics , beta-Lactamases/genetics , Serogroup , China/epidemiology , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial/genetics
12.
Microb Cell Fact ; 23(1): 55, 2024 Feb 17.
Article En | MEDLINE | ID: mdl-38368340

BACKGROUND: Pichia pastoris is a widely utilized host for heterologous protein expression and biotransformation. Despite the numerous strategies developed to optimize the chassis host GS115, the potential impact of changes in cell wall polysaccharides on the fitness and performance of P. pastoris remains largely unexplored. This study aims to investigate how alterations in cell wall polysaccharides affect the fitness and function of P. pastoris, contributing to a better understanding of its overall capabilities. RESULTS: Two novel mutants of GS115 chassis, H001 and H002, were established by inactivating the PAS_chr1-3_0225 and PAS_chr1-3_0661 genes involved in ß-glucan biosynthesis. In comparison to GS115, both modified hosts exhibited a looser cell surface and larger cell size, accompanied by faster growth rates and higher carbon-to-biomass conversion ratios. When utilizing glucose, glycerol, and methanol as exclusive carbon sources, the carbon-to-biomass conversion rates of H001 surpassed GS115 by 10.00%, 9.23%, and 33.33%, respectively. Similarly, H002 exhibited even higher increases of 32.50%, 12.31%, and 53.33% in carbon-to-biomass conversion compared to GS115 under the same carbon sources. Both chassis displayed elevated expression levels of green fluorescent protein (GFP) and human epidermal growth factor (hegf). Compared to GS115/pGAPZ A-gfp, H002/pGAPZ A-gfp showed a 57.64% higher GFP expression, while H002/pPICZα A-hegf produced 66.76% more hegf. Additionally, both mutant hosts exhibited enhanced biosynthesis efficiencies of S-adenosyl-L-methionine and ergothioneine. H001/pGAPZ A-sam2 synthesized 21.28% more SAM at 1.14 g/L compared to GS115/pGAPZ A-sam2, and H001/pGAPZ A-egt1E obtained 45.41% more ERG at 75.85 mg/L. The improved performance of H001 and H002 was likely attributed to increased supplies of NADPH and ATP. Specifically, H001 and H002 exhibited 5.00-fold and 1.55-fold higher ATP levels under glycerol, and 6.64- and 1.47-times higher ATP levels under methanol, respectively, compared to GS115. Comparative lipidomic analysis also indicated that the mutations generated richer unsaturated lipids on cell wall, leading to resilience to oxidative damage. CONCLUSIONS: Two novel P. pastoris chassis hosts with impaired ß-1,3-D-glucan biosynthesis were developed, showcasing enhanced performances in terms of growth rate, protein expression, and catalytic capabilities. These hosts exhibit the potential to serve as attractive alternatives to P. pastoris GS115 for various bioproduction applications.


Methanol , Pichia , Saccharomycetales , Humans , Pichia/metabolism , Methanol/metabolism , Glycerol/metabolism , Adenosine Triphosphate/metabolism , Carbon/metabolism , Cell Wall/metabolism , Polysaccharides/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism
13.
Aquat Toxicol ; 267: 106830, 2024 Feb.
Article En | MEDLINE | ID: mdl-38198987

Environmental pollution is considered to lead to Ulva sp. green tides. Nevertheless, nutrients with high concentrations inhibit algae which may be damaged by antibiotics, such as OTC (oxytetracycline). Thus, Ulva sp. algae might pay a physiological cost under nutrient-OTC combined pressures. If this hypothesis is confirmed, Ulva sp. algae cannot easily form green tides, or green tides are difficult to maintain. To test this hypothesis, an uniform design experiment during which OTC, ammonia (NH4-N) and phosphate (PO4-P) were factors was set to simulate nutrient-OTC combined pressures, and Ulva lactuca was exposed to the pressures for 96 h. The TN (total nitrogen, CTN) or TP (total phosphorus, CTP) content in U. lactuca increased with increasing nutrient concentrations, as CTN = 21.206±1.000+ 1.227±0.418NH4-N × PO4-P (R2 = 0.282, p < 0.05) and CTP = 1.886±0.266+ 0.877±0.126PO4-P (R2 = 0.689, p < 0.05), respectively. The increase in dry weight of U. lactuca (Wdry) had a relationship with combined pressures, Wdry = 0.011±0.029 - 0.036±0.014PO4-P (R2 = 0.243, p < 0.05), i.e., the algal growth was inhibited by increasing PO4-P concentration. The SOD (Superoxide dismutase) activity (ASOD) was stimulated by OTC, as ASOD = 127.868±8.741+9.587±4.179 OTC (R2 = 0.193, p < 0.05). The contents of Chl a and b (Ca and Cb) were negatively affected by OTC or PO4-P with high concentration, as Ca = 0.566±0.042 - 0.024±0.022 OTC × PO4-P (R2 = 0.179, p < 0.05) and Cb = 0.512±0.043-0.044±0.020PO4-P (R2 = 0.180, p < 0.05). Thus, too high concentrations of PO4-P or OTC may hinder the formation and maintenance of Ulva sp. green tides.


Edible Seaweeds , Oxytetracycline , Ulva , Water Pollutants, Chemical , Water Pollutants, Chemical/toxicity , Nutrients , Superoxide Dismutase
14.
J Cell Physiol ; 239(2): e31162, 2024 Feb.
Article En | MEDLINE | ID: mdl-37994152

The developmental fate of ovarian follicles is primarily determined by the survival status (proliferation or apoptosis) of granulosa cells (GCs). Owing to the avascular environment within follicles, GCs are believed to live in a hypoxic niche. Follicle-stimulating hormone (FSH) has been reported to improve GCs survival by governing hypoxia-inducible factor-1α (HIF-1α)-dependent hypoxia response, but the underlying mechanisms remain poorly understood. Growth arrest-specific gene 6 (GAS6) is a secreted ligand of tyrosine kinase receptors, and has been documented to facilitate tumor growth. Here, we showed that the level of GAS6 was markedly increased in mouse ovarian GCs after the injection of FSH. Specifically, FSH-induced GAS6 expression was accompanied by HIF-1α accumulation under conditions of hypoxia both in vivo and in vitro, whereas inhibition of HIF-1α with small interfering RNAs/antagonist repressed both expression and secretion of GAS6. As such, Luciferase reporter assay and chromatin immunoprecipitation assay showed that HIF-1α directly bound to a hypoxia response element site within the Gas6 promoter and contributed to the regulation of GAS6 expression in response to FSH. Notably, blockage of GAS6 and/or its receptor Axl abrogated the pro-survival effects of FSH under hypoxia. Moreover, phosphorylation of Axl by GAS6 is required for FSH-mediated Akt activation and the resultant pro-survival phenotypes. Finally, the in vitro findings were verified in vivo, which showed that FSH-induced proliferative and antiapoptotic effects in ovarian GCs were diminished after blocking GAS6/Axl using HIF-1α antagonist. These findings highlight a novel function of FSH in preserving GCs viability against hypoxic stress by activating the HIF-1a-GAS6-Axl-Akt pathway.


Proto-Oncogene Proteins c-akt , Signal Transduction , Animals , Female , Mice , Follicle Stimulating Hormone/pharmacology , Granulosa Cells/metabolism , Hypoxia/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Mice, Inbred ICR
15.
FASEB J ; 38(1): e23332, 2024 01.
Article En | MEDLINE | ID: mdl-38095232

Severe hypoxia induced by vascular compromise (ovarian torsion, surgery), obliteration of vessels (aging, chemotherapy, particularly platinum drugs) can cause massive follicle atresia. On the other hand, hypoxia increases the occurrence of DNA double-strand breaks (DSBs) and triggers cellular damage repair mechanisms; however, if the damage is not promptly repaired, it can also induce the apoptosis program. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone that plays essential roles in stimulating mammalian follicular development. Here, we report a novel role for IGF-I in protecting hypoxic GCs from apoptosis by promoting DNA repair through the homologous recombination (HR) process. Indeed, the hypoxic environment within follicles significantly inhibited the efficiency of HR-directed DNA repair. The presence of IGF-I-induced HR pathway to alleviate hypoxia-induced DNA damage and apoptosis primarily through upregulating the expression of the RAD51 recombinase. Importantly, we identified a new transcriptional regulator of RAD51, namely E2F8, which mediates the protective effects of IGF-I on hypoxic GCs by facilitating the transcriptional activation of RAD51. Furthermore, we demonstrated that the PI3K/AKT pathway is crucial for IGF-I-induced E2F8 expression, resulting in increased RAD51 expression and enhanced HR activity, which mitigates hypoxia-induced DNA damage and thereby protects against GCs apoptosis. Together, these findings define a novel mechanism of IGF-I-mediated GCs protection by activating the HR repair through the PI3K/AKT/E2F8/RAD51 pathway under hypoxia.


Proto-Oncogene Proteins c-akt , Recombinational DNA Repair , Female , Animals , Swine , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Insulin-Like Growth Factor I/genetics , DNA Repair , Homologous Recombination , Rad51 Recombinase/genetics , Hypoxia , Granulosa Cells/metabolism , Apoptosis , Mammals/metabolism
16.
Physiol Plant ; 175(6): e14088, 2023.
Article En | MEDLINE | ID: mdl-38148205

Oilseed rape and other crops of Brassica napus have a high demand for boron (B). Boron deficiencies result in the inhibition of root growth, and eventually premature flower abortion. Understanding the genetic mechanisms underlying flower abortion in B-limiting conditions could provide the basis to enhance B-efficiency and prevent B-deficiency-related yield losses. In this study, we assessed transcriptomic responses to B-deficiency in diverse inflorescence tissues at multiple time points of soil-grown plants that were phenotypically unaffected by B-deficiency until early flowering. Whilst transcript levels of known B transporters were higher in B-deficient samples, these remained remarkably stable as the duration of B-deficiency increased. Meanwhile, GO-term enrichment analysis indicated a growing response resembling that of a pathogen or pest attack, escalating to a huge transcriptome response in shoot heads at mid-flowering. Grouping differentially expressed genes within this tissue into MapMan functional bins indicated enrichment of genes related to wounding, jasmonic acid and WRKY transcription factors. Individual candidate genes for controlling the "flowering-without-seed-setting" phenotype from within MapMan biotic stress bins include those of the metacaspase family, which have been implicated in orchestrating programmed cell death. Overall temporal expression patterns observed here imply a dynamic response to B-deficiency, first increasing expression of B transporters before recruiting various biotic stress-related pathways to coordinate targeted cell death, likely in response to as yet unidentified B-deficiency induced damage-associated molecular patterns (DAMPs). This response indicates new pathways to target and dissect to control B-deficiency-induced flower abortion and to develop more B-efficient crops.


Brassica napus , Transcriptome , Transcriptome/genetics , Inflorescence/genetics , Inflorescence/metabolism , Brassica napus/genetics , Brassica napus/metabolism , Boron/metabolism , Gene Expression Profiling , Membrane Transport Proteins/metabolism
17.
Opt Express ; 31(22): 36754-36769, 2023 Oct 23.
Article En | MEDLINE | ID: mdl-38017819

This paper proposes a high-precision phase retrieval method based on deep learning to extract the Zernike coefficients from a single-frame interferogram with an irregular-shaped aperture. Once the Zernike coefficients are obtained, the phase distribution can be retrieved directly using the Zernike polynomials. For many apertures, the root mean square (RMS) of the residual wavefront between the true and estimated wavefronts reached the order of 10-3 λ. Simulations were conducted under different noise conditions, indicating that the proposed method has high measurement accuracy and robustness. Experiments demonstrated that the accuracy achieved by this method was comparable to that of commercial phase-shifting interferometers. We believe that this method is useful for measuring optical surfaces with irregular apertures.

18.
Opt Express ; 31(22): 37241-37249, 2023 Oct 23.
Article En | MEDLINE | ID: mdl-38017857

Based on non-collinear phase-matching (PM), a new method for widely tunable wavelength was proposed and demonstrated in a four-mirror ring cavity of non-critical phase-matching (NCPM) KTiOAsO4 (KTA) optical parametric oscillator (OPO). Wavelength tuning range of 141 nm from 1535.56 nm to 1676.73 nm was achieved by moving one mirror of ring cavity back and forth. The tuning theory and tuning method of non-collinear PM were analyzed in detail. The output energy and pulse width of signal were measured and compared in collinear and non-collinear PM condition. This method is also applicable to OPOs of other nonlinear crystals based on four-mirror ring cavity.

19.
J Agric Food Chem ; 71(49): 19705-19716, 2023 Dec 13.
Article En | MEDLINE | ID: mdl-38029323

Our previous study with artificial intelligence (AI)-assisted screening found that diosmin, a natural flavonoid extracted from citrus, may affect myoblast proliferation and differentiation. At present, few studies have been conducted regarding the biological function of diosmin in muscle cells. Here, using molecular biological techniques, we found that diosmin elevated the proliferation ability of C2C12 myoblasts via activating the Akt/FOXO1 pathway to promote FOXO1 nuclear export, thus repressing p27 protein expression, increasing CDK2, CDK4, and cyclin D1 and cyclin E1 protein expression and accelerating cell cycle transformation, which contributed to myogenesis. Moreover, diosmin suppressed differentiation of C2C12 myoblasts by delaying the terminal exit of the cell cycle in early differentiated myoblasts and inhibiting autophagic flux in mature myotubes. Furthermore, diosmin promoted myogenesis by activating the Akt/FOXO1 pathway to facilitate myoblast proliferation, which had a positive biological effect on the repair of muscle injury. This study revealed the effect and mechanism of diosmin on skeletal muscle cells and simultaneously provided a new candidate drug for the treatment of myopathy.


Diosmin , Proto-Oncogene Proteins c-akt , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Diosmin/metabolism , Diosmin/pharmacology , Artificial Intelligence , Cell Proliferation , Myoblasts , Cell Differentiation , Muscle Development
20.
Cancer Epidemiol ; 87: 102489, 2023 12.
Article En | MEDLINE | ID: mdl-37979223

INTRODUCTION: Despite advances in oncologic care, racial and socio-economic outcome disparities persist in non-ocular melanoma patients. However, the unmet need is understanding the population at risk for late tumor stage at diagnosis. We sought to analyze the groups with an increased risk of unfavorable tumor stage at diagnosis. METHODS: Patients with non-ocular melanoma were reviewed using the 2000-2019 SEER Research Data (SEER*Stat) and grouped into early tumor stage at diagnosis (stage I-IIC) and late (stage III-IVC). Multivariable logistic and Cox regression examined the association of demographic, socioeconomic, and clinical factors with late-stage diagnosis and overall survival, respectively. Kaplan-Meier estimates were calculated with racial and county-level household income stratification to evaluate overall survival differences. RESULTS: Of 147,606 patients diagnosed with non-ocular melanoma, 38,695 cases were identified based on inclusion and exclusion criteria and separated into those with early-stage diagnosis (median 63 years) and those with late-stage (median 62 years). Male gender, Black race, Asian or Pacific Islander race, and Hispanic ethnicity were significantly associated with late-stage tumor diagnosis (p < 0.001). Receipt of surgery and a median county-level household income >$75,000 were protective for late-stage tumor diagnosis (p < 0.001). Additionally, male gender, Black, Asian or Pacific Islander, American Indian/Alaskan Native races, metastasis, and late-stage diagnosis were associated with factors significantly associated with decreased overall survival (p-value <0.001). Receipt of surgery and a median household income of $50,000-$74,999 and >$75,000 were factors associated with increased overall survival (p < 0.001). The median overall survival was 89 months, but Black patients (58 months) and <$50,000 income households (75 months) had significantly worse survival (p < 0.001). CONCLUSIONS: Hispanic ethnicity, Black and Asian or Pacific Islander race, and low-income households were associated with late-stage non-ocular melanoma at diagnosis. Black, Asian or Pacific Islander and American Indian/Alaskan Native races and lower-income households were associated with worse overall survival. Identifying addressable causal factors that link this at-risk population to poor cancer prognosis is warranted.


Ethnic and Racial Minorities , Health Status Disparities , Melanoma , Humans , Male , Asian , Ethnicity , Hispanic or Latino , Melanoma/diagnosis , Melanoma/epidemiology , Melanoma/ethnology , Black or African American , Pacific Island People , American Indian or Alaska Native , Middle Aged , Income
...