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1.
Nat Immunol ; 22(3): 358-369, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33432230

RESUMO

CD8+ T cell exhaustion dampens antitumor immunity. Although several transcription factors have been identified that regulate T cell exhaustion, the molecular mechanisms by which CD8+ T cells are triggered to enter an exhausted state remain unclear. Here, we show that interleukin-2 (IL-2) acts as an environmental cue to induce CD8+ T cell exhaustion within tumor microenvironments. We find that a continuously high level of IL-2 leads to the persistent activation of STAT5 in CD8+ T cells, which in turn induces strong expression of tryptophan hydroxylase 1, thus catalyzing the conversion to tryptophan to 5-hydroxytryptophan (5-HTP). 5-HTP subsequently activates AhR nuclear translocation, causing a coordinated upregulation of inhibitory receptors and downregulation of cytokine and effector-molecule production, thereby rendering T cells dysfunctional in the tumor microenvironment. This molecular pathway is not only present in mouse tumor models but is also observed in people with cancer, identifying IL-2 as a novel inducer of T cell exhaustion.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Interleucina-2/metabolismo , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Neoplasias/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Microambiente Tumoral , 5-Hidroxitriptofano/metabolismo , Animais , Anticorpos Neutralizantes/farmacologia , Antineoplásicos/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Interleucina-2/antagonistas & inibidores , Interleucina-2/genética , Células Jurkat , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Células MCF-7 , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células NIH 3T3 , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/patologia , Receptores de Hidrocarboneto Arílico/deficiência , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Triptofano Hidroxilase/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Biochem Genet ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609670

RESUMO

The polycystic ovary syndrome (PCOS), a common endocrine disorder, is mainly related to infertility. Moreover, it is characterized by promoted androgen, suppressed ovulation and insulin resistance. Long non-coding RNA X inactive specific transcript (lncRNA XIST), known as an oncogene or a cancer inhabited factor, is involved in several disease. However, the diagnostic mechanisms of lncRNA XIST in PCOS have not been clarified. Our study aimed to explain whether lncRNA XIST regulates KGN cells proliferation and apoptosis via microRNA (miR)-212-3p/RASA1 axis in PCOS. Levels of lncRNA XIST, miR-212-3p and RASA1 in KGN cells were detected through reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay. Fluorescence in situ Hybridization (FISH) was performed to confirm the expression of lncRNA XIST and miR-212-3p in KGN cells. StarBase and dual-luciferase reporter assay were applied for exploring the interaction between miR-212-3p and RASA1. Cell viability, apoptosis, protein expression of Bcl-2 and Bax were assessed by MTT, flow cytometry analysis, RT-qPCR and western blot, respectively. We found that lncRNA XIST was low-expressed, miR-212-3p was over-expressed, and RASA1 was dramatically down-regulated in KGN cells. LncRNA XIST negatively regulated miR-212-3p expression in KGN cells. MiR-212-3p interacted with RASA1 and negatively regulated RASA1 levels in KGN cells. Up-regulation of lncRNA XIST signally decreased cells viability, stimulated more apoptotic cells, enhanced Bax expression, and depressed Bcl-2 level in KGN cells. However, these observations were abolished after miR-212-3p mimic treatment. Furthermore, miR-212-3p inhibitor significantly inhibited cell proliferation, enhanced more apoptotic cells, increased Bax expression, and decreased Bcl-2 level in KGN cells, and these effects were eliminated by RASA1-siRNA transfection. Our observations revealed that lncRNA XIST protects against PCOS through regulating miR-212-3p/RASA1 axis, suggesting that lncRNA XIST may be a promising therapeutic target for PCOS therapy.

3.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38894440

RESUMO

Quasi-bound state in the continuum (QBIC) can effectively enhance the interaction of terahertz (THz) wave with matter due to the tunable high-Q property, which has a strong potential application in the detection of low-concentration biological samples in the THz band. In this paper, a novel THz metamaterial sensor with a double-chain-separated resonant cavity structure based on QBIC is designed and fabricated. The process of excitation of the QBIC mode is verified and the structural parameters are optimized after considering the ohmic loss by simulations. The simulated refractive index sensitivity of the sensor is up to 544 GHz/RIU, much higher than those of recently reported THz metamaterial sensors. The sensitivity of the proposed metamaterial sensor is confirmed in an experiment by detecting low-concentration lithium citrate (LC) and bovine serum albumin (BSA) solutions. The limits of detection (LoDs) are obtained to be 0.0025 mg/mL (12 µM) for LC and 0.03125 mg/mL (0.47 µM) for BSA, respectively, both of which excel over most of the reported results in previous studies. These results indicate that the proposed THz metamaterial sensor has excellent sensing performances and can well be applied to the detection of low-concentration biological samples.


Assuntos
Técnicas Biossensoriais , Soroalbumina Bovina , Soroalbumina Bovina/química , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Limite de Detecção , Animais , Radiação Terahertz , Bovinos , Espectroscopia Terahertz/métodos , Refratometria , Compostos de Lítio/química , Ácido Cítrico/química
4.
Int Wound J ; 21(2): e14774, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361180

RESUMO

This meta-analysis aims to comprehensively assess the impact of laparoscopic radical prostatectomy (LRP) on wound infection in patients with prostate cancer (PCa). A systematic search was conducted, from database inception to November 2023, in EMBASE, Google Scholar, Cochrane Library, PubMed, Wanfang and China National Knowledge Infrastructure databases for randomized controlled trials (RCTs) comparing LRP with open radical prostatectomy (ORP) in the treatment of PCa. Two researchers independently screened the literature, extracted data and conducted quality assessments based on pre-defined inclusion and exclusion criteria. Stata 17.0 software was employed for data analysis. Overall, 15 RCTs involving 1458 PCa patients were included. The analysis revealed the incidence of wound infection (odds ratio [OR] = 0.28, 95% confidence interval [CI] = 0.16-0.51, p < 0.001) and complications (OR = 0.27, 95% CI = 0.20-0.37, p < 0.001) was significantly lower in the LRP group compared to the ORP group. This study demonstrates that LRP in PCa patients can effectively reduce the incidence of wound infections and complications, indicating significant therapeutic efficacy and justifying its broader clinical application.


Assuntos
Laparoscopia , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Infecção dos Ferimentos , Masculino , Humanos , Neoplasias da Próstata/cirurgia , Prostatectomia/efeitos adversos , Laparoscopia/efeitos adversos , Infecção dos Ferimentos/cirurgia
5.
Biochem Biophys Res Commun ; 642: 11-20, 2023 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36543019

RESUMO

Endothelial progenitor cells (EPCs) are crucial for the maintenance of vascular homeostasis. The dysfunction of EPCs contributes to the endothelial damage in hypertension. Andrographolide (AGP) is a traditional Chinese patent medicine that has been reported to have protective effects on cardiovascular system. However, the effect of AGP on the function of EPCs in hypertension remains unknown. In this study, we aimed to elucidate the effect of AGP on EPCs and the underlying mechanisms. In vivo, the blood pressure and endothelial function (indicated by endothelial dependent vasodilation) of AGP-fed angiotensin II (Ang II)-infused hypertensive mice were examined. In vitro, the function of EPCs isolated from bone marrow were evaluated by tube formation, migration, and adhesion assay. Additionally, a silent information regulator 1 (SIRT1) inhibitor/agonist and a small interfering RNA (si-RNA) targeting SIRT1 were used to determine the pathway involved. The results showed that AGP not only reduced blood pressure, improved endothelial function in hypertensive mice but also restored the dysfunction of EPCs of hypertension in vitro. Mechanistically, AGP up-regulated SIRT1 expression, decreased the Bax/Bcl-2 ratio and the expression level of Cleaved caspase-3, thus inhibiting the apoptosis of Ang II induced EPCs. However, the beneficial effects of AGP on EPCs disappeared after the inhibition or the knockdown of SIRT1. To summarize, this study demonstrates for the first time that AGP improves the dysfunction of EPCs through SIRT1-mediated anti-apoptotic effects. Our findings might provide a novel therapeutic strategy for treating vascular damage in hypertension.


Assuntos
Células Progenitoras Endoteliais , Hipertensão , Camundongos , Animais , Células Progenitoras Endoteliais/metabolismo , Angiotensina II/farmacologia , Sirtuína 1/metabolismo , Células Cultivadas , Hipertensão/metabolismo
6.
Biochem Biophys Res Commun ; 671: 205-214, 2023 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-37302296

RESUMO

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) provide added vascular protection beyond glucose lowering to patients with type 2 diabetes mellitus (T2DM). Endothelial progenitor cells (EPCs) are an important endogenous repair mechanism for diabetic vascular complications. Yet, whether SGLT2i protect vessels in diabetic patients by improving the function of EPCs remains to be elucidated. Here we enrolled Sixty-three T2DM patients and 60 healthy participants and 15 of T2DM group took dapagliflozin for 3 months. Retinal capillary density (RCD) was examined before and after meditation. Moreover, vasculogenic capacity of EPCs cocultured with or without dapagliflozin in vitro and in vivo (hind limb ischemia model) were assessed. Mechanically, genes related to inflammation/oxidative stress, and the AMPK signaling of EPCs were determined. Our results found T2DM demonstrated a declined RCD and a decreased number of circulating EPCs compared with healthy controls. Compared with the EPCs from healthy individuals, vasculogenic capacity of T2DM EPCs was significantly impaired, which could be restored by dapagliflozin meditation or dapagliflozin coculture. Increased expression of inflammation correlative genes and decreased anti-oxidative stress related genes expression were found in EPCs form T2DM, which were accompanied with reduced phosphorylation level of AMPK. Dapagliflozin treatment activated AMPK signaling, decreased the level of inflammation and oxidative stress, and rescued vasculogenic capacity of EPCs from T2DM. Furthermore, AMPK inhibitor pretreatment diminished the enhancement vasculogenic capacity of diabetic EPCs from dapagliflozin treatment. This study demonstrates for the first time that dapagliflozin restores vasculogenic capacity of EPCs via activating AMPK-mediated inhibition of inflammation and oxidative stress in T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Células Progenitoras Endoteliais , Humanos , Células Progenitoras Endoteliais/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Estresse Oxidativo , Glucose/metabolismo
7.
J Hum Genet ; 68(9): 625-634, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37161033

RESUMO

Chromosomal rearrangements mostly result from non-allelic homologous recombination mediated by low-copy repeats (LCRs) or segmental duplications (SDs). Recent studies on recombinant chromosome 18 (rec (18)) have focused on diagnoses and clinical phenotypes. We diagnosed two cases of prenatal rec (18) and identified precise breakpoint intervals using karyotype and chromosomal microarray analyses. We analyzed the distribution characteristics of breakpoint repetitive elements to infer rearrangement mechanisms and reviewed relevant literature to identify genetic trends. Among the 12 families with 25 pregnancies analyzed, 68% rec (18), 24% spontaneous abortions, and 8% normal births were reported. In the 17 rec (18) cases, 65% presented maternal origin and 35% were paternal. Short-arm breakpoints at p11.31 were reported in 10 cases, whereas the long-arm breakpoints were located at q21.3 (6 cases) and q12 (4 cases). Breakpoints of pericentric inversions on chromosome 18 are concentrated in p11.31, q21.3, and q12 regions. Rearrangements at 18p11.31 are non-recurrent events. ALUs, LINE1s, and MIRs were enriched at the breakpoint regions (1.85 to 3.42-fold enrichment over the entire chromosome 18), while SDs and LCRs were absent. ALU subfamilies had sequence identities of 85.94% and 83.01% between two pair breakpoints. Small repetitive elements may mediate recombination-coupled DNA repair processes, facilitating rearrangements on chromosome 18. Maternal inversion carriers are more prone to abnormal recombination in prenatal families with rec (18). Recombinant chromosomes may present preferential segregation during gamete formation.


Assuntos
Cromossomos Humanos Par 18 , Rearranjo Gênico , Humanos , Gravidez , Feminino , Cariotipagem , Inversão Cromossômica/genética
8.
Opt Lett ; 48(14): 3681-3684, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37450724

RESUMO

Cophasing is crucial for segmented or sparse aperture telescopes to achieve high resolution. In this Letter, we propose a novel, to the best of our knowledge, model-based piston correction method that can remove large-scale piston errors within a few iterations using extended objects. The relation between the piston error and a metric function is derived theoretically under broadband illumination. The metric function is based on the image's power spectral density at the spatial frequency where the sidelobe peak of the modulation transfer function (MTF) appears. The piston error is iteratively estimated and corrected by introducing positive and negative piston biases. The dynamic range of piston correction can be as large as the coherence length of light. The correction accuracy in experiments is affected by the image noises and the accuracy of the introduced piston biases.

9.
Exp Cell Res ; 418(1): 113244, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35697078

RESUMO

PLIN2 has been found to be dysregulated in several human malignancies, which influences cancer progression. However, the roles of PLIN2 in regulating hepatocellular carcinoma (HCC) progression are still unclear. Here, we revealed that PLIN2 was frequently upregulated in HCC cells and tissues, and increased PLIN2 expression was associated with poor prognosis outcomes in HCC. In HCC cells, overexpressing PLIN2 promoted cell proliferation, PLIN2-deficiency inhibited cell vitality. Mechanistically, silencing of PLIN2 expression downregulated hypoxia inducible factor 1-α (HIF1α) expression and this downregulation in turn inhibited the targeting genes of HIF1α. Furthermore, we found that PLIN2 stabilized and retarded the degradation of the HIF1α through autophagy-lysosomal pathway by inhibiting AMPK/ULK1. Collectively, we clarified the carcinogenic role of PLIN2 in HCC and suggested a prognostic biomarker for diagnosis and clinical therapy in the future.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Autofagia/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/patologia , Perilipina-2/metabolismo
10.
Nano Lett ; 22(10): 3983-3992, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35548949

RESUMO

Lysosome-targeting self-assembling prodrugs had emerged as an attractive approach to overcome the acquisition of resistance to chemotherapeutics by inhibiting lysosomal sequestration. Taking advantage of lysosomal acidification induced intracellular hydrolytic condensation, we developed a lysosomal-targeting self-condensation prodrug-nanoplatform (LTSPN) system for overcoming lysosome-mediated drug resistance. Briefly, the designed hydroxycamptothecine (HCPT)-silane conjugates self-assembled into silane-based nanoparticles, which were taken up into lysosomes by tumor cells. Subsequently, the integrity of the lysosomal membrane was destructed because of the acid-triggered release of alcohol, wherein the nanoparticles self-condensed into silicon particles outside the lysosome through intracellular hydrolytic condensation. Significantly, the LTSPN system reduced the half-maximal inhibitory concentration (IC50) of HCPT by approximately 4 times. Furthermore, the LTSPN system realized improved control of large established tumors and reduced regrowth of residual tumors in several drug-resistant tumor models. Our findings suggested that target destructing the integrity of the lysosomal membrane may improve the therapeutic effects of chemotherapeutics, providing a potent treatment strategy for malignancies.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Linhagem Celular Tumoral , Resistência a Medicamentos , Humanos , Lisossomos/patologia , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Silanos/farmacologia , Silanos/uso terapêutico
11.
Appl Energy ; 334: 120676, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36714219

RESUMO

During the SARS-CoV-2 (COVID-19) pandemic, governments around the world have formulated policies requiring ventilation systems to operate at a higher outdoor fresh air flow rate for a sufficient time, which has led to a sharp increase in building energy consumption. Therefore, it is necessary to identify an energy-efficient ventilation strategy to reduce the risk of infection. In this study, we developed an occupant-number-based model predictive control (OBMPC) algorithm for building ventilation systems. First, we collected the occupancy and Heating, ventilation, and air conditioning system (HVAC) data from March to July 2021. Then, four different models (Auto regression moving average-based multilayer perceptron (ARMA_MLP), Recurrent neural networks (RNN), Long short-term memory networks (LSTM), and Nonhomogeneous Markov with change points detection (NH_Markov)) were used to predict the number of room occupants from 15 min to 24 h ahead with an interval output. We found that each model could predict the number of occupants with 85 % accuracy using a one-person offset. The accuracy of 15 min of the ahead prediction could reach 95 % with a one-person offset, but none of them could track abrupt changes. The occupancy prediction results were used to calculate the ventilation demand using the Wells-Riley equation, and the upper bound can maintain an infection risk lower than 2 % for 93 % of the day. This OBMPC model could reduce the coil load by 52.44 % and shift the peak load by 3 h up to 5 kW compared with 24 × 7 h full outdoor air (OA) system when people wear masks in the space. The occupancy prediction uncertainty could cause a 9 % to 26 % difference in demand ventilation, a 0.3 °C to 2.4 °C difference in zone temperature, a 28.5 % to 44.5 % difference in outdoor airflow rate, and a 10.7 % to 28.2 % difference in coil load.

12.
BMC Microbiol ; 22(1): 186, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906551

RESUMO

BACKGROUND: Cellulolytic microorganisms are considered a key player in the degradation of feed fiber. These microorganisms can be isolated from various resources, such as animal gut, plant surfaces, soil and oceans. A new strain of Bacillus amyloliquefaciens, TL106, was isolated from faeces of a healthy Tibetan pigs. This strain can produce cellulase and shows strong antimicrobial activity in mice. Thus, in this study, to better understand the strain of B. amyloliquefaciens TL106 on degradation of cellulose, the genome of the strain TL106 was completely sequenced and analyzed. In addition, we also explored the cellulose degradation ability of strain TL106 in vitro. RESULTS: TL106 was completely sequenced with the third generation high-throughput DNA sequencing. In vitro analysis with enzymatic hydrolysis identified the activity of cellulose degradation. TL106 consisted of one circular chromosome with 3,980,960 bp and one plasmid with 16,916 bp, the genome total length was 3.99 Mb and total of 4,130 genes were predicted. Several genes of cellulases and hemicellulase were blasted in Genbank, including ß-glucosidase, endoglucanase, ß-glucanase and xylanase genes. Additionally, the activities of amylase (20.25 U/mL), cellulase (20.86 U/mL), xylanase (39.71 U/mL) and ß-glucanase (36.13 U/mL) in the fermentation supernatant of strain TL106 were higher. In the study of degradation characteristics, we found that strain TL106 had a better degradation effect on crude fiber, neutral detergent fiber, acid detergent fiber, starch, arabinoxylan and ß-glucan of wheat and highland barley . CONCLUSIONS: The genome of B. amyloliquefaciens TL106 contained several genes of cellulases and hemicellulases, can produce carbohydrate-active enzymes, amylase, cellulase, xylanase and ß-glucanase. The supernatant of fermented had activities of strain TL106. It could degrade the fiber fraction and non-starch polysaccharides (arabinoxylans and ß-glucan) of wheat and highland barley. The present study demonstrated that the degradation activity of TL106 to crude fiber which can potentially be applied as a feed additive to potentiate the digestion of plant feed by monogastric animals.


Assuntos
Bacillus amyloliquefaciens , Celulase , Hordeum , beta-Glucanas , Amilases , Animais , Bacillus amyloliquefaciens/genética , Bacillus amyloliquefaciens/metabolismo , Celulase/genética , Celulase/metabolismo , Celulose/metabolismo , Detergentes , Fibras na Dieta , Camundongos , Suínos , Tibet , Triticum , Sequenciamento Completo do Genoma , beta-Glucosidase/genética
13.
Opt Express ; 30(6): 9088-9102, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299345

RESUMO

The correction of wavefront sensorless adaptive optics (WFSless AO) can be significantly accelerated by using a holographic modal wavefront sensor (HMWFS). The HMWFS is realized by a computer-generated hologram (CGH) into which all aberration modes to be detected are encoded and only a single-shot image is required for simultaneous measurement of multiple modes. The conventional HMWFS suffers from a quite limited dynamic range and severe inter-modal crosstalk which deteriorates the sensing accuracy. We proposed a novel HMWFS with a large dynamic range and no crosstalk and validated its performance by simulation and experiment. In the improved HMWFS scheme, the aberration is represented by Lukosz modes whose gradients are orthogonal and the modal coefficients can be estimated independently. Instead of using a binary CGH in conventional HMWFS, a kinoform CGH with high diffraction efficiency is adopted in the improved HMWFS. The kinoform CGH is produced by a phase-only liquid-crystal spatial light modulator (LCSLM) which also serves as a wavefront corrector in our WFSless AO system.

14.
Opt Express ; 30(6): 9562-9577, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299381

RESUMO

The deformable mirror (DM) in conventional model-based wavefront sensorless adaptive optics (WFSless AO) must be calibrated in advance by an additional WFS in order to precisely generate predetermined bias modes with known amplitudes. Although the WFS is unnecessary during correction, it will increase system complexity and may be unavailable in real applications. In this paper, the model-based WFSless AO algorithms, either for point-like or extended objects, are generalized to a unified form and the calibration problem comes down to the measurement of a Gram matrix. We proposed a novel self-calibration procedure to obtain the Gram matrix without using a WFS. The calibrated Gram matrix can be used directly for simultaneous correction if using the influence functions of DM as the bias modes, requiring N+1 images to correct N modes. Alternatively, orthogonal or gradient-orthogonal mirror modes obtained from the eigenvectors of the Gram matrix can be used as the modal basis to implement independent sequential correction that requires 2N images to correct N modes. Simulations and experiments have been done to verify the feasibility of proposed self-calibration and correction methods for both point-like and extended objects in a WFSless AO system.

15.
Opt Lett ; 47(24): 6401-6404, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36538448

RESUMO

On-orbit cophasing is essential for high-resolution imaging of space telescopes with a segmented primary mirror. A model-based fine phasing method for a segmented mirror is proposed and demonstrated in this Letter. The tip-tilt error is related to the second moment of spot intensity, and the piston error is related to the Strehl ratio. Chebyshev segmented piston-tip-tilt (CSPTT) modes are used to express cophasing errors to suppress the effect of imaging noises. The CSPTT modal coefficients are estimated by the "2N + 1" algorithm that introduces bidirectional biases for each mode's estimation. The proposed method is proved robust to image noises and figure errors.

16.
Anim Cogn ; 25(5): 1345-1355, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35397722

RESUMO

Conspecific aggressiveness often increases after social isolation for species that are not entirely solitary, and this increased aggression could also be reversed after resocialization. However, literature on this aggression plasticity refers to either permanently social or low-level subsocial species in invertebrates. Examinations of conspecific aggressiveness reversibility in high-level subsocial invertebrates, in which offspring cohabitate with parents for a certain period of time after sexual maturation, would enhance the understanding of the role of conspecific-aggression plasticity in social evolution. Here, using the lactating spider Toxeus magnus, which exhibits extremely high-level subsociality, we assessed three questions. (1) Is its conspecific aggression affected by social living and/or kinship? The results indicated that conspecific aggression increased after social isolation, while kinship did not affect aggressiveness. (2) Could the social-isolation-induced higher aggression be reversed after resocialization? The results showed that the increased aggression of the spiders could be reversed 3 days after resocialization. (3) What is the proximate mechanism that caused the aggression reversibility by resocialization? A simulated resocialization experiment in which single spider was provided with mirrors demonstrated that the visual cues of conspecifics alone could reverse the aggression after 6 days. These results indicate that the high-level subsocial invertebrate showed aggressiveness reversibility without chemical cues. This is more similar to permanently social species rather than to low-level subsocial species, and visual cues could be vital to induce aggression change. These results suggest that conspecific-aggression reversibility might play a key role in social evolution and may functionally enhance species' adaptiveness under variable conditions.


Assuntos
Aranhas , Feminino , Animais , Aranhas/fisiologia , Comportamento Social , Comportamento Animal/fisiologia , Lactação , Agressão/fisiologia , Isolamento Social
17.
Skin Pharmacol Physiol ; 35(3): 137-147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34883492

RESUMO

INTRODUCTION: Although it has been reported that the antidiabetic drug metformin has multiple extra-hypoglycemic activities, such as anti-oxidation, antiaging, and even antitumor, topical metformin also can induce hair regeneration, but the precise mechanism involved in that process is still unclear. OBJECTIVES: The aim of this study was to assess the effect of metformin on hair growth in a mouse hair-follicle reconstitution model generated by in vitro self-assembled three-dimensional aggregates of epidermal and dermal cells (DCs) (3D aggregates). METHODS: Epidermal cells and DCs were isolated and cultured from the mouse skin of 50 C57BL/6 mouse pups (1-day-old). For tracing the distribution of DCs during the self-assembly process of 3D aggregates, the DCs were labeled with Vybrant Dil Cell-Labeling Solution and mixed with epidermal cells at a 1:1 ratio. Formed 3D aggregates were treated with 10 mM metformin and then were grafted into recipient BALB/c nude mice. The biomarkers (hepatocyte growth factor [HGF], prominin-1 [CD133], alkaline phosphatase [ALP], ß-catenin, and SRY-box transcription factor 2 [SOX2]) associated with the hair-inductive activity of DCs were detected in the grafted skin tissues and in cultured 3D aggregates treated with metformin using immunofluorescent staining, quantitative real-time RT-PCR (qRT-PCR), and Western blotting. Furthermore, the expression levels of CD133 were also examined in DCs with different passage numbers using qRT-PCR and Western blotting. RESULTS: Metformin directly stimulates the activity of ALP of cultured 3D aggregates, upregulates both the protein and mRNA expression levels of molecular markers (HGF, CD133, ALP, ß-catenin, and SOX2), and improves the survival rate of reconstituted hair follicles. Moreover, we also found that metformin increases the expression of CD133 in DCs thus maintaining their trichogenic capacity that would normally be lost by serial subculture. CONCLUSIONS: These results suggest that metformin can promote hair follicle regeneration in vitro through upregulation of the hair-inductive capability of DCs, warranting further evaluation in the clinical treatment of male or female pattern hair loss.


Assuntos
Metformina , beta Catenina , Animais , Células Cultivadas , Feminino , Cabelo , Folículo Piloso , Masculino , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , beta Catenina/genética
18.
Molecules ; 27(13)2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35807286

RESUMO

As a typical dibenzylisoquinoline alkaloid, tetrandrine (TET) is clinically used for the treatment of silicosis, inflammatory pulmonary, and cardiovascular diseases in China. Recent investigations have demonstrated the outstanding anticancer activity of this structure, but its poor aqueous solubility severely restricts its further development. Herein, a series of its 14-N-amino acid-substituted derivatives with improved anticancer effects and aqueous solubility were designed and synthesized. Among them, compound 16 displayed the best antiproliferative activity against human colorectal cancer (HCT-15) cells, with an IC50 value of 0.57 µM. Compared with TET, 16 was markedly improved in terms of aqueous solubility (by 5-fold). Compound 16 significantly suppressed the colony formation, migration, and invasion of HCT-15 cells in a concentration-dependent manner, with it being more potent in this respect than TET. Additionally, compound 16 markedly impaired the morphology and motility of HCT-15 cells and induced the death of colorectal cancer cells in double-staining and flow cytometry assays. Western blot results revealed that 16 could induce the autophagy of HCT-15 cells by significantly decreasing the content of p62/SQSTM1 and enhancing the Beclin-1 level and the ratio of LC3-II to LC3-I. Further study showed that 16 effectively inhibited the proliferation, migration, and tube formation of umbilical vein endothelial cells, manifesting in a potent anti-angiogenesis effect. Overall, these results revealed the potential of 16 as a promising candidate for further preclinical studies.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Aminoácidos/farmacologia , Antineoplásicos/química , Apoptose , Benzilisoquinolinas , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Células Endoteliais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
19.
Angew Chem Int Ed Engl ; 61(18): e202116893, 2022 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-35181975

RESUMO

Intravesical administration of first-line drugs has shown failure in the treatment of bladder cancer owing to the poor tumor retention time of chemotherapeutics. Herein, we report an intracellular hydrolytic condensation (IHC) system to construct long-term retentive nano-drug depots in situ, wherein sustained drug release results in highly efficient suppression of bladder cancer. Briefly, the designed doxorubicin (Dox)-silane conjugates self-assemble into silane-based prodrug nanoparticles, which condense into silicon particle-based nano-drug depots inside tumor cells. Significantly, we demonstrate that the IHC system possesses highly potent antitumor efficacy, which leads to the regression and eradication of large established tumors and simultaneously extends the overall survival of air pouch bladder cancer mice compared with that of mice treated with Dox. The concept of intracellular hydrolytic condensation can be extended via conjugating other chemotherapeutic drugs, which may facilitate rational design of novel nanomedicines for augmentation of chemotherapy.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias da Bexiga Urinária , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Masculino , Camundongos , Nanopartículas/uso terapêutico , Silanos , Neoplasias da Bexiga Urinária/tratamento farmacológico
20.
Int J Cancer ; 148(11): 2640-2651, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33180334

RESUMO

Liquid biopsy is a revolutionary strategy in cancer diagnosis and prognosis prediction, which is used to analyze cancer cells or cancer-derived products through biofluids such as blood, urine and so on. Exosomes play a crucial role in mediating cell communication. A growing number of studies have reported that exosomes are involved in tumorigenesis, tumor growth, metastasis and drug resistance by delivering cargos including nucleic acids and protein. Thus, exosomes, as a new type of liquid biopsy, have the potential to be diagnostic or prognostic biomarkers. Herein, we elaborate on the current methods and introduce novel techniques for exosome isolation and characterization. Moreover, we elucidate the advantages of exosomes compared to other biological components in liquid biopsy and summarize the different exosomal biomarkers in cancer diagnosis and prognosis prediction.


Assuntos
Exossomos/genética , Exossomos/metabolismo , Neoplasias/diagnóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Detecção Precoce de Câncer , Humanos , Biópsia Líquida , Neoplasias/genética , Neoplasias/metabolismo , Prognóstico
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