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1.
Mol Cancer ; 23(1): 113, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802795

RESUMO

BACKGROUND: The role of circRNAs in hepatocellular carcinoma (HCC) progression remains unclear. CircPIAS1 (circBase ID: hsa_circ_0007088) was identified as overexpressed in HCC cases through bioinformatics analysis. This study aimed to investigate the oncogenic properties and mechanisms of circPIAS1 in HCC development. METHODS: Functional analyses were conducted to assess circPIAS1's impact on HCC cell proliferation, migration, and ferroptosis. Xenograft mouse models were employed to evaluate circPIAS1's effects on tumor growth and pulmonary metastasis in vivo. Bioinformatics analysis, RNA immunoprecipitation, and luciferase reporter assays were utilized to elucidate the molecular pathways influenced by circPIAS1. Additional techniques, including RNA pulldown, fluorescence in situ hybridization (FISH), chromatin immunoprecipitation (ChIP), qPCR, and western blotting, were used to further explore the underlying mechanisms. RESULTS: CircPIAS1 expression was elevated in HCC tissues and cells. Silencing circPIAS1 suppressed HCC cell proliferation and migration both in vitro and in vivo. Mechanically, circPIAS1 overexpression inhibited ferroptosis by competitively binding to miR-455-3p, leading to upregulation of Nuclear Protein 1 (NUPR1). Furthermore, NUPR1 promoted FTH1 transcription, enhancing iron storage in HCC cells and conferring resistance to ferroptosis. Treatment with ZZW-115, an NUPR1 inhibitor, reversed the tumor-promoting effects of circPIAS1 and sensitized HCC cells to lenvatinib. CONCLUSION: This study highlights the critical role of circPIAS1 in HCC progression through modulation of ferroptosis. Targeting the circPIAS1/miR-455-3p/NUPR1/FTH1 regulatory axis may represent a promising therapeutic strategy for HCC.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carcinoma Hepatocelular , Proliferação de Células , Ferroptose , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , MicroRNAs , Proteínas de Neoplasias , RNA Circular , Animais , Feminino , Humanos , Masculino , Camundongos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Progressão da Doença , Ferroptose/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , RNA Circular/genética , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Neurol Sci ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38965115

RESUMO

OBJECTIVE: To investigate the effect of intravenous thrombolysis (IVT) before endovascular therapy (EVT) on outcomes in acute ischemic stroke of large core. METHODS: The studies comparing functional outcomes after EVT with and without IVT were systematically searched up to October 10th, 2023. Odds ratio (OR) was pooled using random effects model. Subgroup analysis was performed stratified by study design, country or region, study date, imaging methods and time window. RESULTS: Thirteen studies were included, enrolling 1717 patients. The pooled rate of functional independence in patients receiving IVT + EVT was 26% (95% CI 20% - 33%), significantly higher than 18% (95% CI 15% - 20%) in those receiving EVT alone (OR 1.55, 95% CI 1.13-2.12, P = 0.006; I²= 23.9%). In subgroup analysis, prior IVT increased the probability of functional independence in retrospective studies (OR 1.97, 95% 1.47-2.63, P < 0.00001; I2 = 0). Non-Asian patients benefit from IVT before EVT for functional independence (OR 2.04, 95% 1.48-2.81, P < 0.0001; I2 = 0), but Asian patients did not (OR 1.45, 95% 0.90-2.35, p = 0.13; I2 = 0). The pooled rate of symptomatic intracranial hemorrhage in patients receiving IVT + EVT was 16% (95% CI 12% - 20%), inclining to be higher than 11% (95% CI 6% - 15%) in those receiving EVT alone without significant difference (OR 1.42, 0.83-2.41, P = 0.20; I²= 12%). CONCLUSIONS: IVT before EVT might increase the probability of functional independence in non-Asian patients with large ischemic core. The results provided clinicians with additional information on selecting eligible patients for EVT.

3.
BMC Med Imaging ; 24(1): 45, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360550

RESUMO

BACKGROUND: Tumor mutational burden (TMB) is one of the most significant predictive biomarkers of immunotherapy efficacy in non-small cell lung cancer (NSCLC). Radiomics allows high-throughput extraction and analysis of advanced and quantitative medical imaging features. This study develops and validates a radiomic model for predicting TMB level and the response to immunotherapy based on CT features in NSCLC. METHOD: Pre-operative chest CT images of 127 patients with NSCLC were retrospectively studied. The 3D-Slicer software was used to outline the region of interest and extract features from the CT images. Radiomics prediction model was constructed by LASSO and multiple logistic regression in a training dataset. The model was validated by receiver operating characteristic (ROC) curves and calibration curves using external datasets. Decision curve analysis was used to assess the value of the model for clinical application. RESULTS: A total of 1037 radiomic features were extracted from the CT images of NSCLC patients from TCGA. LASSO regression selected three radiomics features (Flatness, Autocorrelation and Minimum), which were associated with TMB level in NSCLC. A TMB prediction model consisting of 3 radiomic features was constructed by multiple logistic regression. The area under the curve (AUC) value in the TCGA training dataset was 0.816 (95% CI: 0.7109-0.9203) for predicting TMB level in NSCLC. The AUC value in external validation dataset I was 0.775 (95% CI: 0.5528-0.9972) for predicting TMB level in NSCLC, and the AUC value in external validation dataset II was 0.762 (95% CI: 0.5669-0.9569) for predicting the efficacy of immunotherapy in NSCLC. CONCLUSION: The model based on CT radiomic features helps to achieve cost effective improvement in TMB classification and precise immunotherapy treatment of NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Radiômica , Tomografia Computadorizada por Raios X/métodos , Biomarcadores Tumorais , Imunoterapia
4.
Ren Fail ; 46(1): 2349114, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38770962

RESUMO

BACKGROUND: This review aims to evaluate the safety and efficacy of apixaban vs. vitamin K antagonists (VKAs) in patients on dialysis. METHODS: All types of studies published on PubMed, Embase, CENTRAL, and Web of Science up to 10 September 2023 and comparing outcomes of apixaban vs. VKA in dialysis patients were eligible. RESULTS: Two randomized controlled trials (RCTs) and six retrospective studies were included. Apixaban treatment was associated with significantly lower risk of major bleeding (RR: 0.61; 95% CI: 0.48, 0.77; I2 = 50%) and clinically relevant non-major bleeding (RR: 0.82, 95% CI: 0.68, 0.98, I2 = 9%) compared to VKA. Meta-analysis also showed that the risk of gastrointestinal bleeding (RR: 0.74, 95% CI: 0.64, 0.85, I2 = 16%) and intracranial bleeding (RR: 0.64, 95% CI: 0.49, 0.84, I2 = 0%) was significantly reduced with apixaban. Meta-analysis showed no difference in the risk of ischemic stroke (RR: 0.40, 95% CI: 0.06, 2.69, I2 = 0%), mortality (RR: 1.26, 95% CI: 0.74, 2.16, I2 = 94%) and recurrent venous thromboembolism (RR: 1.02, 95% CI: 0.87, 1.21, I2 = 0%) between the two groups. Subgroup analysis of RCTs showed no difference in bleeding outcomes. CONCLUSIONS: Low-quality evidence from a mix of RCTs and retrospective studies shows that apixaban may have better safety and equivalent efficacy as compared to VKA in dialysis patients. Apixaban treatment correlated with significantly reduced risk of major bleeding and clinically relevant nonmajor bleeding in observational studies but not in RCTs. The predominance of retrospective data warrants caution in the interpretation of results.


Assuntos
Inibidores do Fator Xa , Pirazóis , Piridonas , Diálise Renal , Vitamina K , Humanos , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Hemorragia/induzido quimicamente , Pirazóis/efeitos adversos , Pirazóis/uso terapêutico , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitamina K/antagonistas & inibidores
5.
Lab Invest ; 103(7): 100130, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36925047

RESUMO

Collectin subfamily member 10 (COLEC10), a C-type lectin mainly expressed in the liver, is involved in the development of hepatocellular carcinoma (HCC). However, its underlying molecular mechanism in HCC progression remains unknown. In this study, reduced COLEC10 expression in tumor tissues was validated using various HCC cohorts and was associated with poor patient prognosis. COLEC10 overexpression attenuated HCC cell growth and migration abilities in vitro and in vivo. We identified that COLEC10 was a novel interactor of 78-kDa glucose-regulated protein (GRP78), a master modulator of the unfolded protein response in the endoplasmic reticulum (ER). COLEC10 overexpression potentiated ER stress in HCC cells, as demonstrated by elevated expression levels of phosphorylated protein kinase RNA-like ER kinase, phosphorylated inositol-requiring protein 1α, activating transcription factor 4, DNA damage-inducible transcript 3, and X-box-binding protein 1s. The ER in COLEC10-overexpressing cells also showed a dilated and fragmented pattern. Mechanistically, COLEC10 overexpression increases GRP78 occupancy through direct binding by the C-terminal carbohydrate recognition domain in the ER, which released and activated the ER stress transducers protein kinase RNA-like ER kinase and phosphorylated inositol-requiring protein 1α, triggering the unfolded protein response activity. COLEC10-overexpressing HCC cells generated a relatively high reactive oxygen species level and switched to apoptotic cell death under sorafenib-treated conditions. Our study provides the first novel view that COLEC10 inhibits HCC progression by regulating GRP78-mediated ER stress signaling and may serve as a promising therapeutic and prognostic biomarker.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Chaperona BiP do Retículo Endoplasmático , Neoplasias Hepáticas/metabolismo , Estresse do Retículo Endoplasmático , Apoptose , RNA , Proteínas Quinases , Colectinas
6.
Nat Prod Rep ; 40(9): 1498-1520, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37581222

RESUMO

Time span of literature covered: up to mid-2023Iterative type I polyketide synthases (iPKSs) are outstanding natural chemists: megaenzymes that repeatedly utilize their catalytic domains to synthesize complex natural products with diverse bioactivities. Perhaps the most fascinating but least understood question about type I iPKSs is how they perform the iterative yet programmed reactions in which the usage of domain combinations varies during the synthetic cycle. The programmed patterns are fulfilled by multiple factors, and strongly influence the complexity of the resulting natural products. This article reviews selected reports on the structural enzymology of iPKSs, focusing on the individual domain structures followed by highlighting the representative programming activities that each domain may contribute.


Assuntos
Produtos Biológicos , Policetídeo Sintases , Policetídeo Sintases/metabolismo , Domínio Catalítico , Catálise , Produtos Biológicos/química
7.
Chemistry ; 29(16): e202203656, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36445818

RESUMO

Herein, we report the design and scalable synthesis of three new Co(III) complexes, which have an unusual hydrocarbon η1 -alkyl-η3 -allyl-η5 -cyclopentadienyl ligation structure, from the reactions of readily available cobalt(II) compound CoCl2 (PPh3 )2 and biomass material ß-pinene via C-C bond activation. These Co(III) complexes are air-stable, fairly volatile, and thermally stable, so they are excellent candidates as the metal precursors for the vapor deposition of cobalt-containing thin films. As a demonstration, we show that the Co(III) complex of [(3'-5'-η,1-σ)-methylene(2,2,4-trimethyl-4-cyclohexene-1,3-diyl)](η5 -methylcyclopentadienyl)Co (i. e. (seco-pinene)(MeCp)Co) is well suited for the atomic layer deposition (ALD) of Co3 O4 and CoS2 thin films, and the deposited Co3 O4 and CoS2 films are able to conformally cover trench structures with a fairly high aspect ratio of 10 : 1.

8.
Curr Osteoporos Rep ; 21(2): 241-252, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36881265

RESUMO

PURPOSE OF REVIEW: The purpose of this review is to summarize the different roles of the transcription factor SP7 in regulating bone formation and remodeling, discuss current studies in investigating the causal relationship between SP7 mutations and human skeletal disease, and highlight potential therapeutic treatments that targeting SP7 and the gene networks that it controls. RECENT FINDINGS: Cell-type and stage-specific functions of SP7 have been identified during bone formation and remodeling. Normal bone development regulated by SP7 is strongly associated with human bone health. Dysfunction of SP7 results in common or rare skeletal diseases, including osteoporosis and osteogenesis imperfecta with different inheritance patterns. SP7-associated signaling pathways, SP7-dependent target genes, and epigenetic regulations of SP7 serve as new therapeutic targets in the treatment of skeletal disorders. This review addresses the importance of SP7-regulated bone development in studying bone health and skeletal disease. Recent advances in whole genome and exome sequencing, GWAS, multi-omics, and CRISPR-mediated activation and inhibition have provided the approaches to investigate the gene-regulatory networks controlled by SP7 in bone and the therapeutic targets to treat skeletal disease.


Assuntos
Osteogênese Imperfeita , Osteogênese , Humanos , Osteogênese/genética , Osteogênese Imperfeita/genética , Osso e Ossos , Mutação , Transdução de Sinais/genética , Fator de Transcrição Sp7/genética
9.
Neurol Sci ; 44(12): 4193-4203, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37500992

RESUMO

BACKGROUND: Diabetes mellitus is a known risk factor for Parkinson's disease (PD), but does this risk vary with antidiabetic medications is still unclear. This meta-analysis aims to compile evidence from the literature to assess the risk of idiopathic PD with various oral antidiabetic medications. METHODS: Databases PubMed, CENTRAL, Scopus, Web of Science, and Embase were searched till 5th April 2023. Adjusted outcomes were pooled to generate a hazard ratio (HR) on the risk of PD with different antidiabetic medications. RESULTS: Fifteen studies with 2,910,405 diabetic patients were eligible. Pooled analysis failed to show any significant difference in the risk of PD among users of metformin (HR: 1.05 95% CI: 0.91, 1.22 I2 = 81%), glitazones (HR: 0.84 95% CI: 0.68, 1.05 I2 = 91%), glucagon-like peptide-1 agonists (HR: 0.63 95% CI: 0.26, 1.55 I2 = 33%), and sulfonylureas (HR: 1.13 95% CI: 0.96, 1.32 I2 = 76%). However, a meta-analysis of four studies showed that dipeptidyl peptidase-4 inhibitor use was associated with reduced risk of PD in diabetics (HR: 0.69 95% CI: 0.56, 0.86 I2 = 46%). Insufficient data was available on sodium-glucose cotransporter-2 inhibitors, α-glucosidase inhibitors, and glinides. CONCLUSIONS: Limited retrospective evidence indicates that DPP4i may reduce the risk of idiopathic PD in diabetics. Metformin, sulfonylureas, glucagon-like peptide-1 agonists, and glitazones were not associated with any change in the risk of PD. Further studies taking into confounding factors and using a common comparator group are needed to strengthen present evidence.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Doença de Parkinson , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Peptídeo 1 Semelhante ao Glucagon , Hipoglicemiantes/efeitos adversos , Metformina/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/epidemiologia , Doença de Parkinson/complicações , Estudos Retrospectivos , Compostos de Sulfonilureia/efeitos adversos , Tiazolidinedionas/efeitos adversos
10.
Appl Opt ; 62(3): 683-687, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36821272

RESUMO

We demonstrated the optical frequency transfer over a 96 km urban business network in Shanghai. The key factors affecting the optical frequency transmission system, such as fiber link quality, feedback compensation strength, and out-of-loop fiber temperature variation, are studied for the urban fiber link characteristics. The effective suppression technique of complex urban fiber link noise with different feedback compensation parameters is studied. With active phase noise suppression, the optical frequency stability can reach 1.9×10-16 at 1 s and 2.2×10-18 at 10,000 s over a 96 km urban fiber link. This work potentially plays an important role in optical clock frequency comparison, and it makes a good foundation for future research on long-distance optical frequency transfer over an urban business network.

11.
Am J Transplant ; 22(9): 2246-2253, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35373451

RESUMO

Thrombospondin-1 (TSP-1) is a key mediator of renal ischemia-reperfusion injury (IRI), a major cause of kidney dysfunction under various disease conditions and a risk factor of renal allograft rejection. In this study, we developed a nanotechnology-based therapy targeting TSP-1 to prevent renal IRI. A biocompatible nanoparticle (NP) capable of specific binding to TSP-1 was prepared by conjugating NPs with TSP-1-binding (LSKL) peptides. LSKL/NPs not only effectively adsorbed recombinant TSP-1 proteins in vitro, but also efficiently neutralized TSP-1 in mice undergoing renal IRI. IRI-induced elevation of TSP-1 in the kidney was significantly inhibited by post-IR treatment with LSKL/NPs, but not free LSKL or NPs. Furthermore, TSP-1 proteins adsorbed on LSKL/NPs were functionally inactive and unable to induce apoptosis in renal tubular epithelial cells. Importantly, LSKL/NPs induced strong protection against renal IRI, as shown by markedly diminished serum creatinine levels and improved histological lesions of the kidney. Thus, LSKL/NPs provide a useful means of depleting and inactivating TSP-1 and a potential therapy for renal IRI.


Assuntos
Transplante de Rim , Nanopartículas , Traumatismo por Reperfusão , Animais , Apoptose , Rim/patologia , Transplante de Rim/efeitos adversos , Camundongos , Camundongos Endogâmicos C57BL , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Trombospondina 1/antagonistas & inibidores , Trombospondina 1/metabolismo , Trombospondina 1/farmacologia
12.
Opt Express ; 30(25): 45980-45987, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522990

RESUMO

We propose a novel scheme that uses only a single passive phase compensation device to achieve stable optical and radio frequency joint transfer. The phase noises of optical and radio frequency can be simultaneously compensated by passively embedding their phase information on the two optical carrier sidebands generated by an electro-optical modulator without using the phase discrimination and active servo controller. As a result, this scheme has many advantages, such as high spectral purity, short settling time and infinite compensation accuracy. We experimentally demonstrate the joint transfer of optical and 1 GHz RF over 120 km fiber spools. The optical frequency stability achieves 6.9 × 10-17 at 1 s and 7.03 × 10-19 at 10000 s, while the 1 GHz RF is 6.47 × 10-13 at 1 s and 3.96 × 10-16 at 10000 s.

13.
Curr Osteoporos Rep ; 20(6): 493-504, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36087214

RESUMO

PURPOSE OF REVIEW: The purpose of this review is to discuss the molecular mechanisms involved in osteocyte dendrite formation, summarize the similarities between osteocytic and neuronal projections, and highlight the importance of osteocyte dendrite maintenance in human skeletal disease. RECENT FINDINGS: It is suggested that there is a causal relationship between the loss of osteocyte dendrites and the increased osteocyte apoptosis during conditions including aging, microdamage, and skeletal disease. A few mechanisms are proposed to control dendrite formation and outgrowth, such as via the regulation of actin polymerization dynamics. This review addresses the impact of osteocyte dendrites in bone health and disease. Recent advances in multi-omics, in vivo and in vitro models, and microscopy-based imaging have provided novel approaches to reveal the underlying mechanisms that regulate dendrite development. Future therapeutic approaches are needed to target the process of osteocyte dendrite formation.


Assuntos
Osso e Ossos , Osteócitos , Humanos , Osteócitos/metabolismo , Envelhecimento , Dendritos/fisiologia
14.
Zhonghua Nan Ke Xue ; 28(7): 603-607, 2022 Jul.
Artigo em Zh | MEDLINE | ID: mdl-37556217

RESUMO

OBJECTIVE: To investigate the correlation of the anterior lobe thickness of the prostate (ALTP) with bladder outlet obstruction (BOO), and evaluate the effect of ALTP on the clinical progression of BPH. METHODS: This retrospective study included 159 cases of BPH. We obtained the clinical indicators of the patients, including ALTP, prostate volume (PV), postvoid residual urine (PVR), maximum urinary flow rate (Qmax), BOO index (BOOI) and IPSS, and analyzed the correlations of ALTP with IPSS, PV, Qmax, age, PVR and BOOI. Using the ROC curve and cut-off point of ALTP, we compared the clinical indicators between the small and large ALTP groups, and analyzed the correlation between ALTP and the clinical progression of BPH. RESULTS: IPSS was not significantly correlated with ALTP (P > 0.05), nor was ALTP with PV and Qmax (P > 0.05). The area under the ROC curve was 0.742 (95% CI: 0.656-0.828) and the cut-off point of ALTP was 0.65 cm. Statistically significant differences were observed in PV, Qmax, IPSS and the rate of surgery between the small ALTP (<0.65 cm) and large ALTP (≥0.65 cm) groups (P < 0.05). CONCLUSION: ALTP is not proportional to PV or to IPSS. ALTP ≥ 0.65 cm increases the incidence of BOO, and may be a risk factor for the clinical progression of BPH.


Assuntos
Hiperplasia Prostática , Obstrução do Colo da Bexiga Urinária , Retenção Urinária , Masculino , Humanos , Hiperplasia Prostática/complicações , Próstata , Estudos Retrospectivos , Obstrução do Colo da Bexiga Urinária/etiologia , Progressão da Doença
15.
Opt Express ; 29(8): 11693-11701, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984945

RESUMO

We demonstrate a new optical pulse amplitude modulation (PAM) scheme where joint ultrastable time-frequency and gigabit ethernet data transfer with the same laser wavelength is realized. Time transmission is compatible with the White Rabbit (WR) based on gigabit ethernet networks, and frequency transmission is achieved by using 100MHz radio frequency (RF) modulation and the round-trip compensation methods. The laser is on-off keying (OOK) modulated by the WR signal, the RF and WR signal are modulated by optical PAM in a Mach-Zehnder interferometer modulator (MZM), and the local and remote site are connected by 96km urban fiber in Shanghai. The experimental results demonstrate that the frequency instabilities are 5.7E-14/1 s and 5.9E-17/104s, and the time interval transfer of 1 pulse per second (PPS) signal with less than 300fs stability after 104 s are obtained. This novel scheme can transmit frequency signals at hydrogen-maser-level stability in the gigabit ethernet network.

16.
Opt Express ; 29(9): 14041-14057, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33985130

RESUMO

Fiber-optic time and frequency synchronization technology demonstrates ultra-high synchronization performance and has been gradually applied in various fields. Based on frequency synchronization, this study addressed the problems of period ambiguity and initial phase uncertainty of the phase signal to realize the coherent transmission of the phase. An absolute phase marking technology was developed based on high-speed digital logic with zero-crossing detection and an optimized control strategy. It can realize picosecond-level absolute phase marking and provide a picosecond-level ultra-low peak-to-peak jitter pulse marking signal to eliminate phase period ambiguity and determine initial phase and transmission delay. Thus, by combining the high-precision phase measurement capability of the synchronized frequency signal and long-distance ambiguity elimination capability of the pulse-per-second signal, a high-precision remote coherent phase transmission over an optical fiber is realized. After frequency synchronization, the peak-to-peak jitter between the local and remote phase-marking signals can be only 3.3 ps within 10,000 s measurement time. The uncertainty of the coherent phase transmission is 2.577 ps. This technology can significantly improve the phase coherence of fiber-optic time and frequency transmission and provide a new approach to achieve peak-to-peak picosecond-level reference phase marking and high-precision fiber-optic remote coherent phase transmission. This demonstrates broad application prospects in coherence fields such as radar networking.

17.
Microvasc Res ; 133: 104076, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956647

RESUMO

The adverse environment in early life can modulate adult phenotype, including blood pressure. Our previous study shows, in a rat streptozotocin (STZ)-induced maternal diabetes model, fetal exposure to maternal diabetes is characterized by established hypertension in the offspring. However, the exact mechanisms are not known. Our present study found, as compared with male control mother offspring (CMO), male diabetic mother offspring (DMO) had higher blood pressure with arterial dysfunction, i.e., decreased acetylcholine (Ach)-induced vasodilation. But there is no difference in blood pressure between female CMO and DMO. The decreased Ach-induced vasodilation was related to decreased nitric oxide (NO) production in the endothelium, not NO sensitivity in vascular smooth muscle because sodium nitroprusside (SNP)-mediated vasodilation was preserved; there was decreased NO production and lower eNOS phosphorylation in male DMO. The reactive oxygen species (ROS) level was increased in male DMO than CMO; normalized ROS levels with tempol increased NO production, normalized Ach-mediated vasodilation, and lowered blood pressure in male DMO rats. It indicates that diabetic programming hypertension is related to arterial dysfunction; normalizing ROS might be a potential strategy for the prevention of hypertension in the offspring.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Gestacional , Endotélio Vascular/fisiopatologia , Hipertensão/etiologia , Artéria Mesentérica Superior/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Fatores Etários , Animais , Pressão Arterial , Glicemia/metabolismo , GMP Cíclico/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Gestacional/sangue , Diabetes Gestacional/fisiopatologia , Endotélio Vascular/metabolismo , Feminino , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Artéria Mesentérica Superior/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo , Gravidez , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fatores Sexuais , Vasodilatação
18.
Pak J Pharm Sci ; 34(1): 65-67, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34248004

RESUMO

This study was designed to scrutinize the clinical effectiveness of intrathecal injection of medicine along with constant lumbar cistern drainage on intracranial infection subsequent to intracranial tumor operation. Sixty two patients with intracranial infection after intracranial tumor surgery were selected as the objects of study divided into combined treatment group (n=31) and the control group (n=31) according to the time of admission. Patients in the combined treatment group were treated with intrathecal injection of medicine combined with group's continuous lumbar cistern drainage while patients in the control group were just treated with intravenous antibiotic therapy followed by comparison in the clinical efficacy, infection control, the level of inflammatory factor like crp, IL-4 and incidence of complication in the two groups were compared respectively. The total effectiveness rate was 96.77% in the combined treatment group and 80.65% in the control group indicating statistical significant difference (p<0.05). The average time of infection control in the combined treatment group and the control group was 9.05±2.08 and 17.07±3.34 days respectively. After treatment, the restoration effect of serum crp and IL-4 in the combined treatment group was better (p<0.05). The complication incidence of patients in the combined treatment group was 3.23% while it was 16.13% in the control group. Therefore, the difference between the two groups was statistically significant (p<0.05).This advanced combination therapy proved to be effective as the total clinical efficacy was relatively high. Moreover, the combination therapy also shortened the time of infection control with lesser complication rate and reduce inflammatory factor.


Assuntos
Antibacterianos/administração & dosagem , Neoplasias Encefálicas/cirurgia , Drenagem/métodos , Injeções Espinhais/métodos , Vértebras Lombares , Infecção da Ferida Cirúrgica/terapia , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/diagnóstico , Resultado do Tratamento
19.
Gastroenterology ; 156(3): 662-675.e7, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30342037

RESUMO

BACKGROUND & AIMS: Activation of KRAS signaling and overexpression of the aurora kinase A (AURKA) are often detected in luminal gastrointestinal cancers. We investigated regulation of ribosomal protein S6 kinase B1 (RPS6KB1) by AURKA and the effects of alisertib, an AURKA inhibitor, in mice xenograft tumors grown from human gastrointestinal cancer cells with mutant, activated forms of KRAS. METHODS: We tested the effects of alisertib or AURKA overexpression or knockdown in 10 upper gastrointestinal or colon cancer cell lines with KRAS mutations or amplifications using the CellTiter-Glo luminescence and clonogenic cell survival assays. We used the proximity ligation in situ assay to evaluate protein co-localization and immunoprecipitation to study protein interactions. Nude mice with xenograft tumors grown from HCT116, SNU-601, SW480, or SNU-1 cells were given oral alisertib (40 mg/kg, 5 times/wk) for 4 weeks. Tumor samples were collected and analyzed by immunoblots and immunohistochemistry. Tissue microarrays from 151 paraffin-embedded human colon tumors, with adjacent normal and adenoma tissues, were analyzed by immunohistochemistry for levels of AURKA. RESULTS: Alisertib reduced proliferation and survival of the cell lines tested. AURKA knockdown or inhibition with alisertib reduced levels of phosphorylated RPS6KB1 (at T389) and increased levels of proteins that induce apoptosis, including BIM, cleaved PARP, and cleaved caspase 3. AURKA co-localized and interacted with RPS6KB1, mediating RPS6KB1 phosphorylation at T389. We detected AURKA-dependent phosphorylation of RPS6KB1 in cell lines with mutations in KRAS but not in cells with wild-type KRAS. Administration of alisertib to mice with xenograft tumors significantly reduced tumor volumes (P < .001). Alisertib reduced phosphorylation of RPS6KB1 and Ki-67 and increased levels of cleaved caspase 3 in tumor tissues. In analyses of tissue microarrays, we found significant overexpression of AURKA in gastrointestinal tumor tissues compared with non-tumor tissues (P = .0003). CONCLUSION: In studies of gastrointestinal cancer cell lines with activated KRAS, we found AURKA to phosphorylate RPS6KB1, promoting cell proliferation and survival and growth of xenograft tumors in mice. Agents that inhibit AURKA might slow the growth of gastrointestinal tumors with activation of KRAS.


Assuntos
Aurora Quinase A/antagonistas & inibidores , Azepinas/farmacologia , Neoplasias Gastrointestinais/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Pirimidinas/farmacologia , Animais , Aurora Quinase A/genética , Aurora Quinase A/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Terapia de Alvo Molecular , Inibidores de Proteínas Quinases/farmacologia , Distribuição Aleatória , Sensibilidade e Especificidade , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
20.
BMC Microbiol ; 20(1): 15, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31948391

RESUMO

BACKGROUND: Understanding the patterns of species richness across elevational gradients is a key concept for contemporary research in ecology and evolution, and critical to understanding large-scale trends in biodiversity, global change and conservation. However, patterns of elevational species richness between taxonomic groups, regions and latitudes are inconsistent, so that various, sometimes conflicting hypotheses exist. Several scholars have pointed out that research on elevational distribution patterns is often biased by the sampling design employed. To test this hypothesis, we analyzed species richness of Nematode-Trapping Fungi (NTF) across an elevation gradient at two mountainous sites in western Yunnan Province, P.R. China. We tested for potential differences in the results when using different sampling designs. RESULTS: A total of 3 genera, 17 species, 222 strains of NTF were isolated and identified from Gaoligongshan and Cangshan. Species accumulation curves for both sites and sampling modes had acceptable leveling, demonstrating sufficient sampling effort. At Gaoligongshan, the elevation distribution patterns of NTF were different under two sampling patterns. When reducing the analyzed altitude range in Gaoligongshan, the elevation distribution pattern of the NTF changed. A similar elevation distribution pattern was observed in Cangshan when testing the same altitude range. In general, when treating the same dataset using different sampling designs, the resulting distribution patterns of species richness and occurrence frequencies were clearly different. Moreover, after removal of the samples located within lower-altitude zones affected by anthropogenic interferences, the distribution pattern of NTF in the two sites tended to become uniform. CONCLUSION: The sampling design, and in particular the elevation interval between plots, has a significant effect on the assessment of species distribution in mountainous regions. Other factors such as human activities and the multi-dimensionality of biodiversity also contribute to result biases. It is recommended that sampling design is given careful consideration in future studies on the elevational gradients of species richness, using stratified approaches according to the most relevant factors.


Assuntos
Fungos/classificação , Nematoides/microbiologia , Altitude , Animais , Biodiversidade , China , Demografia , Fungos/isolamento & purificação , Atividades Humanas , Humanos , Especificidade da Espécie
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