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1.
Nat Commun ; 15(1): 1347, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355644

RESUMO

Accurate identification and localization of multiple abnormalities are crucial steps in the interpretation of chest X-rays (CXRs); however, the lack of a large CXR dataset with bounding boxes severely constrains accurate localization research based on deep learning. We created a large CXR dataset named CXR-AL14, containing 165,988 CXRs and 253,844 bounding boxes. On the basis of this dataset, a deep-learning-based framework was developed to identify and localize 14 common abnormalities and calculate the cardiothoracic ratio (CTR) simultaneously. The mean average precision values obtained by the model for 14 abnormalities reached 0.572-0.631 with an intersection-over-union threshold of 0.5, and the intraclass correlation coefficient of the CTR algorithm exceeded 0.95 on the held-out, multicentre and prospective test datasets. This framework shows an excellent performance, good generalization ability and strong clinical applicability, which is superior to senior radiologists and suitable for routine clinical settings.


Assuntos
Anormalidades Múltiplas , Aprendizado Profundo , Humanos , Estudos Prospectivos , Raios X , Cardiomegalia/diagnóstico por imagem
2.
Chin J Integr Med ; 30(1): 52-61, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37340203

RESUMO

OBJECTIVE: To study the in vitro and in vivo antitumor effects of the polysaccharide of Alocasia cucullata (PAC) and the underlying mechanism. METHODS: B16F10 and 4T1 cells were cultured with PAC of 40 µg/mL, and PAC was withdrawn after 40 days of administration. The cell viability was detected by cell counting kit-8. The expression of Bcl-2 and Caspase-3 proteins were detected by Western blot and the expressions of ERK1/2 mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). A mouse melanoma model was established to study the effect of PAC during long-time administration. Mice were divided into 3 treatment groups: control group treated with saline water, positive control group (LNT group) treated with lentinan at 100 mg/(kg·d), and PAC group treated with PAC at 120 mg/(kg·d). The pathological changes of tumor tissues were observed by hematoxylin-eosin staining. The apoptosis of tumor tissues was detected by TUNEL staining. Bcl-2 and Caspase-3 protein expressions were detected by immunohistochemistry, and the expressions of ERK1/2, JNK1 and p38 mRNA were detected by qRT-PCR. RESULTS: In vitro, no strong inhibitory effects of PAC were found in various tumor cells after 48 or 72 h of administration. Interestingly however, after 40 days of cultivation under PAC, an inhibitory effect on B16F10 cells was found. Correspondingly, the long-time administration of PAC led to downregulation of Bcl-2 protein (P<0.05), up-regulation of Caspase-3 protein (P<0.05) and ERK1 mRNA (P<0.05) in B16F10 cells. The above results were verified by in vivo experiments. In addition, viability of B16F10 cells under long-time administration culture in vitro decreased after drug withdrawal, and similar results were also observed in 4T1 cells. CONCLUSIONS: Long-time administration of PAC can significantly inhibit viability and promote apoptosis of tumor cells, and had obvious antitumor effect in tumor-bearing mice.


Assuntos
Alocasia , Camundongos , Animais , Alocasia/metabolismo , Sistema de Sinalização das MAP Quinases , Caspase 3/metabolismo , Apoptose , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
3.
Int J Nanomedicine ; 18: 7901-7922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38148856

RESUMO

Acute liver injury (AIL), a fatal clinical disease featured with a swift deterioration of hepatocyte functions in the short term, has emerged as a serious public health issues that warrants attention. However, the effectiveness of existing small molecular antioxidants and anti-inflammatory medications in alleviating AIL remains uncertain. The unique inherent structural characteristics of liver confer it a natural propensity for nanoparticle capture, which present an opportunity to exploit in the formulation of nanoscale therapeutic agents, enabling their selective accumulation in the liver and thereby facilitating targeted therapeutic interventions. Significantly increased reactive oxygen species (ROS) accumulation and inflammation response have been evidenced to play crucial roles in occurrence and development of AIL. Nanozymes with ROS-scavenging capacities have demonstrated considerable promise in ROS elimination and inflammation regulation, thereby offering an appealing therapeutic instrument for the management of acute liver injury. In this review, the mechanisms of different type of ALI were summarized. In addition, we provide a comprehensive summary and review of the available ROS-scavenging nanozymes, including transition metal-based nanozymes, noble metal nanozymes, carbon-based nanozymes, and some other nanozymes. Furthermore, the challenges still need to be solved in the field of ROS-scavenging nanozymes for ALI alleviation are also discussed.


Assuntos
Hepatócitos , Fígado , Humanos , Espécies Reativas de Oxigênio , Inflamação , Antioxidantes
4.
Opt Express ; 31(18): 28900-28911, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710699

RESUMO

In this paper, for the first time to the best of our knowledge, we investigate the experiment of polar coded probabilistic shaped 8-ary pulse amplitude modulation (PS-PAM8) in weak turbulence. A systematic interleaver (SIL) is proposed to improve the polar code performance for PS-PAM8, compatible with the 5 G channel coding standard. Considering the effects of turbulence and shaped constellations, the pilot with identical distributions as the transmitted data is used for dynamic channel estimation to avoid demodulation failure. Moreover, the application of hybrid equalization with nonlinear and linear equalizers effectively reduces the receiver sensitivity. In 25 GBd transmission over a 4 m free-space link, the transmission performance of polar coded PAM8 schemes with SIL is better than that of the low-density parity check code by 1.0 dB, and the power budget is further saved by 0.72∼0.83 dB after linear equalization. Meanwhile, the shaping gains of polar coded PS-PAM8 with SIL and hybrid equalization are up to 2.0 dB at 1.5 bits/channel use. In addition, different weak turbulence conditions can be generated inside a chamber, and the observed channel fading is consistent with the log-normal model. The results show that the proposed polar coded PS scheme can improve the Q-factor by 0.49∼1.74 dB in different turbulence conditions.

5.
Biomater Sci ; 11(12): 4370-4384, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37144899

RESUMO

Amino acid-based poly(ester urea urethane) (AA-PEUU) is developed from amino acid-based ester urea building blocks interconnected with urethane blocks functionalized with poly(ethylene glycol) (PEG). Each functional block consists of structural design features that could impact the properties and performances of AA-PEUU as a nanocarrier for the systemic delivery of gambogic acid (GA). The multifunctional AA-PEUU structure provides broad tunability to enable the optimization of nanocarriers. The study investigates the structure-property relationship by fine-tuning the structure of AA-PEUU, including the amino acid type, hydrocarbons, the ratio of functional building blocks, and PEGylation, to identify the nanoparticle candidate with optimized delivery performances. Compared to free GA, the optimized PEUU nanocarrier improves the intratumoral distribution of GA by more than 9-fold, which significantly enhances the bioavailability and persistence of GA after intravenous administration. In an MDA-MB-231 xenograft mouse model, GA delivered by the optimized AA-PEUU nanocarrier exhibits significant tumor inhibition, apoptosis induction, and the anti-angiogenesis effect. The study demonstrates the potency of engineering AA-PEUU nanocarriers with tailor-designed structures and versatile tunability for the systemic delivery of therapeutics in the treatment of triple negative breast tumor.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Camundongos , Animais , Aminoácidos , Uretana , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ureia , Ésteres , Nanopartículas/química
6.
J Transl Med ; 21(1): 260, 2023 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-37062842

RESUMO

BACKGROUND: More than half of the colorectal cancer (CRC) patients will develop liver metastasis that underlies the cancer mortality. In the hepatic tumor microenvironment, the interplay between CRC cells and hepatic stellate cells (HSCs), and the activation of HSCs to become carcinoma-associated fibroblasts (CAFs) will further promote the cancer development. Nevertheless, the critical signaling molecule that involved in these processes remains unknown, which hinders the development of effective therapeutic agents for the treatment of metastatic CRC (mCRC). METHODS: Conditioned medium system and co-cultured system were used to examine the interplay between CRC cells and HSCs. Luminex liquid suspension chip detection and enzyme-linked immunosorbent assay were used to screen for the mediators in the conditioned medium that facilitated the CRC-HSCs interplay and HSCs-to-CAFs differentiation. Cell and animal models were used to examine whether brevilin A inhibited CRC liver metastasis via the VEGF-IL6-STAT3 axis. RESULTS: In the CRC-HSCs interplay, CRC promoted HSCs-to-CAFs differentiation by releasing vascular endothelial growth factor (VEGF); and HSCs released interleukin 6 (IL6) that activated signal transducer and activator of transcription 3 (STAT3) in the CRC and hence increased the cancer metastatic potential. The functions of the VEGF-IL6-STAT3 axis in the HSCs-CRC interplay were further validated by VEGF recombinant protein and IL6 neutralizing antibody. More importantly, brevilin A, an active compound isolated from Centipeda minima (L.) A. Br. et Aschers, targeted the VEGF-IL6-STAT3 axis in the CRC-HSCs interplay, hence significantly inhibited colorectal liver metastasis and cancer growth both in vitro and in vivo. CONCLUSIONS: We are the first to demonstrate brevilin A possesses potent anti-mCRC effect by targeting the VEGF-IL6-STAT3 axis in the CRC-HSCs interplay. Our findings not only support the development of brevilin A as a novel therapeutic agent for mCRC treatment, but also pave the path for the development of other VEGF-IL6-STAT3 targeting therapeutic strategies.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Retais , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Interleucina-6/metabolismo , Células Estreladas do Fígado/metabolismo , Fator de Transcrição STAT3/metabolismo , Meios de Cultivo Condicionados , Neoplasias Hepáticas/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral
7.
Mediators Inflamm ; 2023: 3695469, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846195

RESUMO

Asthma is a common respiratory disease characterized by chronic airway inflammation. Dexmedetomidine (DEX), a highly selective α2 adrenergic receptor agonist, has been shown to participate in regulating inflammatory states and thus exert organ protective actions. However, the potential of DEX in asthma is still unknown. This study is aimed at investigating the role of DEX in a mouse model of house dust mite- (HDM-) induced asthma and exploring its underlying mechanism. Here, we found that DEX treatment significantly ameliorated airway hyperresponsiveness, airway inflammation, and airway remodeling in the asthmatic mice, which were similar to the efficacy of the reference anti-inflammatory drug dexamethasone. In addition, DEX reversed the increased expression of toll-like receptor 4 (TLR4) and its downstream signaling adaptor molecule nuclear factor-κB (NF-κB) in the lung tissue of asthmatic mice. Furthermore, these protective effects of DEX were abolished by yohimbine, an α2 adrenergic receptor antagonist. These results indicate that DEX is capable of ameliorating airway inflammation and remodeling in asthmatic mice, and this protective effect is associated with the inhibition of the TLR4/NF-κB signaling pathway.


Assuntos
Asma , Dexmedetomidina , Ratos , Camundongos , Animais , NF-kappa B/metabolismo , Dexmedetomidina/uso terapêutico , Dexmedetomidina/farmacologia , Receptor 4 Toll-Like/metabolismo , Remodelação das Vias Aéreas , Modelos Animais de Doenças , Ratos Sprague-Dawley , Transdução de Sinais , Asma/tratamento farmacológico , Inflamação/tratamento farmacológico
8.
Mol Med Rep ; 27(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36321783

RESUMO

Allergic asthma is a chronic inflammatory disease in which oxidative stress serves a pivotal role. In clinical practice, dexmedetomidine (DEX), an α­2­adrenergic receptor agonist, is used as a sedative. DEX exhibits antioxidative and organ­protective properties. In a murine model of asthma, DEX has a therapeutic effect via the toll like receptor 4/NF­ÐºB signaling pathway; however, whether DEX can exert an antioxidative effect on asthma has yet to be elucidated. In the present study, a T helper (Th)2­dominant murine asthma model was established. DEX treatment significantly reduced eosinophilic airway inflammation, mucus overproduction and airway hyperresponsiveness, as well as the concentrations of Th2 cytokines. The lung tissues of mice with asthma were characterized by redox imbalance (increased oxidative stress and impaired antioxidant capacity). DEX treatment alleviated this imbalance by decreasing the levels of malondialdehyde and reactive oxygen species, and increasing the levels of glutathione. Furthermore, the nuclear factor erythroid 2­related factor 2 (Nrf2) signaling pathway was inhibited in the lung tissues of asthmatic mice; these effects were noted in its downstream genes, heme oxygenase 1 and glutathione peroxidase 4. In mice with asthma, DEX treatment induced the expression of these antioxidant genes and the activation of Nrf2, whereas ML385 (an inhibitor of Nrf2) partially abrogated the antioxidative and therapeutic effects of DEX. To the best of our knowledge, the present study is the first to demonstrate the protective effect of DEX on Th2­dominant asthma through the activation of the Nrf2 signaling pathway. The results suggested that the antioxidative properties of DEX could be beneficial in clinical application of DEX for the relief of asthmatic symptoms.


Assuntos
Asma , Dexmedetomidina , Animais , Camundongos , Antioxidantes/farmacologia , Asma/metabolismo , Dexmedetomidina/farmacologia , Inflamação/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais
9.
Opt Express ; 30(24): 43691-43705, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523062

RESUMO

The modeling and prediction of the ultrafast nonlinear dynamics in the optical fiber are essential for the studies of laser design, experimental optimization, and other fundamental applications. The traditional propagation modeling method based on the nonlinear Schrödinger equation (NLSE) has long been regarded as extremely time-consuming, especially for designing and optimizing experiments. The recurrent neural network (RNN) has been implemented as an accurate intensity prediction tool with reduced complexity and good generalization capability. However, the complexity of long grid input points and the flexibility of neural network structure should be further optimized for broader applications. Here, we propose a convolutional feature separation modeling method to predict full-field ultrafast nonlinear dynamics with low complexity and strong generalization ability with high accuracy, where the linear effects are firstly modeled by NLSE-derived methods, then a convolutional deep learning method is implemented for nonlinearity modeling. With this method, the temporal relevance of nonlinear effects is substantially shortened, and the parameters and scale of neural networks can be greatly reduced. The running time achieves a 94% reduction versus NLSE and an 87% reduction versus RNN without accuracy deterioration. In addition, the input pulse conditions, including grid point numbers, durations, peak powers, and propagation distance, can be generalized accurately during the predicting process. The results represent a remarkable improvement in ultrafast nonlinear dynamics prediction and this work also provides novel perspectives of the feature separation modeling method for quickly and flexibly studying the nonlinear characteristics in other fields.

10.
Opt Express ; 30(17): 30980-30990, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242191

RESUMO

In this paper, the probabilistically shaped polar-coded multiple-input multiple-output free-space optical (MIMO-FSO) communication system with or without spatially correlated (SC) fading is investigated to improve transmission performance. The designed shaping-polar encoder can flexibly generate three typical shapes of distribution via shaping bits and be decoded in the conventional method. The achievable information rate (AIR) of MIMO-FSO systems with or without SC fading is evaluated to determine the number of shaping bits for the shaping-polar encoder. The non-pairwise distributions are demonstrated to be more suitable for turbulence channels than other distributions. The results show that the AIR of the shaped 4 × 4 systems even exceeds that of the uniform 4 × 5 systems in the low signal-to-noise ratio regions over strong turbulence channels. In terms of bit error rate performance, more than 15 dB shaping gains can be achieved by the shaped 4 × 4 systems compared to the uniform single-input single-output polar-coded systems. In addition, the shaped 4 × 4 systems outperform the uniform ones ranging from 1 dB to 1.9 dB over different atmospheric turbulence channels with or without SC fading, comparable to the uniform MIMO systems with one more physical receiver.

11.
Phytomedicine ; 103: 154199, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35679793

RESUMO

BACKGROUND: Liver fibrosis can be easily developed into irreversible liver cirrhosis or even liver cancer. Lysosomal acid lipase (LAL), encoded by the lipase A (Lipa) gene, is a critical enzyme involved in liver fibrosis development. Morroniside, an iridoid glycoside isolated from Cornus officinalis Sieb. et Zucc., exerts hepatic protective effects. However, the mechanism of action underling the anti-liver fibrosis effects of morroniside have not been fully elucidated. PURPOSE: To explore whether Lipa served as a biomarker for liver fibrosis and investigate the anti-liver fibrosis effects of morroniside and the underlying action mechanism in liver fibrosis cell models. METHODS: LAL expression was examined in the liver tissues of CCl4 and high-fat diet (HFD)-induced liver fibrosis animal models. α-smooth muscle actin (α-SMA) level, collagen and GATA family expressions were analyzed by Real-time PCR and Western blot. Putative transcription factor binding sites in the DNA sequences of Lipa was identified by PROMO-ALGGEN v8.3 online software and ENCODE ChIP-Seq Significance Tool. MD simulation was performed to explore the protein-ligand interaction. RESULTS: We found that the expression of hepatic LAL is lower in the liver fibrosis animal models than the control models. The reduced LAL expression is associated with HSCs activation, suggesting LAL is novel liver fibrosis biomarker. More importantly, our data showed that morroniside exerts anti-liver fibrosis effects in vitro. Mechanistic studies reveal that it binds to the hydrophobic sites of GATA3 and also reduces GATA3 expression, which increases LAL expression. CONCLUSIONS: This study, for the first time, suggests LAL is a novel biomarker for liver fibrosis. Besides, morroniside exerts its anti-liver fibrosis effects by targeting GATA3 and LAL and hence inhibits HSC activation. These findings provide strong scientific evidence to support the development of morroniside as novel alternative or complementary therapeutics for liver injury prevention and treatment.


Assuntos
Células Estreladas do Fígado , Esterol Esterase , Animais , Biomarcadores/metabolismo , Glicosídeos , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Esterol Esterase/metabolismo
12.
Biomed Pharmacother ; 150: 112935, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35447543

RESUMO

BACKGROUND: Morphine dependence, a devastating neuropsychiatric condition, may be closely associated with gut microbiota dysbiosis. Ginsenoside Rg1 (Rg1), an active ingredient extracted from the roots of Panax ginseng C.A. Meyer, has potential health-promoting effects on the nervous system. However, its role in substance use disorders remains unclear. Here, we explored the potential modulatory roles of Rg1 in protection against morphine dependence. METHODS: Conditioned place preference (CPP) was used for establishing a murine model of morphine dependence. 16S rRNA gene sequencing and metabolomics were performed for microbial and metabolite analysis. Molecular analysis was tested for evaluating the host serum and brain responses. RESULTS: Rg1 prevented morphine-induced CPP in mice. The 16S rRNA gene-based microbiota analysis demonstrated that Rg1 ameliorated morphine-induced gut microbiota dysbiosis, specifically for Bacteroidetes. Moreover, Rg1 also inhibited gut microbiota-derived tryptophan metabolism and reduced the serotonin, 5-hydroxytryptamine receptor 1B (5-HTR1B), and 5-hydroxytryptamine receptor 2 A (5-HTR2A) levels. However, the Rg1-induced amelioration of CPP was not observed in mice when their gut microbiome was depleted by non-absorbable antibiotics. Subsequently, gavage with Bacteroides vulgatus increased the abundance of Bacteroidetes. B. vulgatus supplementation synergistically enhanced Rg1-alleviated morphine-induced CPP in mice with microbiome knockdown. Co-treatment with B. vulgatus and Rg1 produced suppressive effects against morphine dependency by inhibiting tryptophan metabolism and reducing the serotonin and 5-HTR1B/5-HTR2A levels. CONCLUSIONS: The gut microbiota-tryptophan metabolism-serotonin plays an important role in gut-brain signaling in morphine disorders, which may represent a novel approach for drug dependence treatment via manipulation of the gut microbial composition and tryptophan metabolite.


Assuntos
Microbioma Gastrointestinal , Dependência de Morfina , Animais , Disbiose , Ginsenosídeos , Camundongos , Morfina/farmacologia , Dependência de Morfina/tratamento farmacológico , RNA Ribossômico 16S/genética , Serotonina/farmacologia , Triptofano/metabolismo , Triptofano/farmacologia
13.
Nat Commun ; 13(1): 1388, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296670

RESUMO

Photonic generation of Terahertz (THz) carriers displays high potential for THz communications with a large tunable range and high modulation bandwidth. While many photonics-based THz generations have recently been demonstrated with discrete bulky components, their practical applications are significantly hindered by the large footprint and high energy consumption. Herein, we present an injection-locked heterodyne source based on generic foundry-fabricated photonic integrated circuits (PIC) attached to a uni-traveling carrier photodiode generating high-purity THz carriers. The generated THz carrier is tunable within the range of 0-1.4 THz, determined by the wavelength spacing between the two monolithically integrated distributed feedback (DFB) lasers. This scheme generates and transmits a 131 Gbits-1 net rate signal over a 10.7-m distance with -24 dBm emitted power at 0.4 THz. This monolithic dual-DFB PIC-based THz generation approach is a significant step towards fully integrated, cost-effective, and energy-efficient THz transmitters.

14.
Adv Mater ; 34(19): e2109004, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35276751

RESUMO

Imaging-guided real-time monitoring of the treatment process of inflammatory diseases is important for the timely adjustment of treatment planning to lower unnecessary side effects and improve treatment outcomes. However, it is difficult to reflect the dynamic changes of inflammation in vivo with enough tissue penetration depth. Here a novel nanotheranostic agent (denominated TMSN@PM) with platelet membrane (PM)-coated, tempol-grafted, manganese-doped, mesoporous silica nanoparticles is developed. The PM endows the TMSN@PM with the ability to target inflammation sites, which are verified by fluorescence imaging with Cyanine5 carboxylic acid (Cy5)-labeled TMSN@PM. Under the inflammatory environment (mild acidity and excess reactive oxygen species (ROS)), TMSN@PM can scavenge the excess ROS, thereby alleviating inflammation, degrade, and release manganese ions for enhanced magnetic resonance imaging (MRI). The relaxation changes (ΔR1 ) are almost linearly correlated with the concentration of H2 O2 , which can reflect the degree of inflammation. This method offers a non-invasive imaging-based strategy for early prediction of the therapeutic outcomes in inflammatory therapy, which may contribute to precision medicine in terms of prognostic stratification and therapeutic planning in future.


Assuntos
Manganês , Nanopartículas , Linhagem Celular Tumoral , Humanos , Inflamação/diagnóstico por imagem , Imageamento por Ressonância Magnética , Nanopartículas/uso terapêutico , Espécies Reativas de Oxigênio
15.
Mol Med Rep ; 25(3)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35014685

RESUMO

Dexmedetomidine (DEX) suppresses inflammatory responses and protects against organ injury. The aim of the present study was to investigate the effect of DEX on airway hyperresponsiveness (AHR) and allergic airway inflammation, as well as its underlying mechanism of action in a murine model of ovalbumin (OVA)­induced asthma. A total of 30 female BALB/c mice were divided into 6 groups (n=5 mice/group): Control, OVA, OVA + DEX (20, 30 or 50 µg/kg) and OVA + TAK­242 [a toll­like receptor 4 (TLR4) inhibitor]. The mice were intraperitoneally injected with 20, 30 or 50 µg/kg DEX 1 h before OVA challenge. AHR to inhaled methacholine (Mch) was measured, and the mice were sacrificed 24 h after the last challenge. AHR following Mch inhalation was measured using the FlexiVent apparatus. Hematoxylin and eosin, periodic acid­Schiff and Wright­Giemsa staining was performed to evaluate inflammatory cell infiltration in the lung tissue. The levels of IL­4, IL­5 and IL­13 in the bronchoalveolar lavage fluid were analyzed using ELISA, and their mRNA expression levels in the lung tissue were examined using reverse transcription­quantitative PCR. The protein expression of TLR4, NF­κB and phosphorylated (p)NF­κB in the lung tissue was also detected using immunohistochemistry. In the murine OVA­induced asthma model, DEX decreased AHR following Mch inhalation and reduced the infiltration of inflammatory cells. IL­4, IL­5 and IL­13 levels in the bronchoalveolar lavage fluid were significantly lower following DEX treatment. Furthermore, DEX treatment inhibited the expression of TLR4, NF­κB and p­NF­κB in the lung tissue and exhibited a similar effect to TAK­242 treatment. In conclusion, DEX may attenuate AHR and allergic airway inflammation by inhibiting the TLR4/NF­κB pathway. These results suggested that DEX may represent a potential anti­inflammatory agent for the treatment and management of patients with asthma.


Assuntos
Asma/metabolismo , Dexmedetomidina/farmacologia , NF-kappa B/metabolismo , Hipersensibilidade Respiratória/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Anti-Inflamatórios , Asma/tratamento farmacológico , Asma/etiologia , Asma/patologia , Biomarcadores , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Dexmedetomidina/uso terapêutico , Modelos Animais de Doenças , Suscetibilidade a Doenças , Feminino , Imuno-Histoquímica , Camundongos , Muco/metabolismo , Hipersensibilidade Respiratória/tratamento farmacológico , Hipersensibilidade Respiratória/etiologia , Hipersensibilidade Respiratória/patologia
16.
Eur J Nucl Med Mol Imaging ; 49(7): 2310-2322, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35044495

RESUMO

PURPOSE: To specifically diagnose malignant tumors in DWI using the human telomerase reverse transcriptase (hTERT) promoter-driven AQP1 expression. METHODS: The human telomerase reverse transcriptase (hTERT) promoter-driven AQP1 gene overexpression lentivirus system (hTERT-AQP1) and cytomegalovirus (CMV) promoter-driven AQP1 gene overexpression lentivirus system (CMV-AQP1) were prepared, and transduced into telomerase-positive and -negative cells. The AQP1 expression and DWI signal intensity (SI) change in transduced cells were analyzed. Balb/C nude mice subcutaneous xenograft models derived from lentivirus-transduced telomerase-positive and -negative cells were used to evaluate AQP1 expression and DWI SI change in vivo. We further established another group of subcutaneous xenograft model using pristine telomerase-positive and -negative cells, followed by injecting the lentiviral vectors intratumorally or intravenously, to determine the malignant tumor-targeted imaging of hTERT-AQP1. RESULTS: The hTERT-AQP1 and CMV-AQP1 were successfully prepared. After transduction, hTERT-AQP1 could induce the specific overexpression of AQP1 in telomerase-positive cells. Compared with untransduced cells, all CMV-AQP1-pretransduced cells and hTERT-AQP1-pretransduced telomerase-positive cells showed decreased SI and increased apparent diffusion coefficient (ADC) in DWI, while hTERT-AQP1-pretransduced telomerase-negative cells showed no obvious SI and ADC change. Correspondingly, hTERT-AQP1-transduced telomerase-positive tumors and CMV-AQP1-transduced telomerase-positive and -negative tumors showed decreased DWI SI and increased ADC, while hTERT-AQP1-transduced telomerase-negative tumor had no SI and ADC changes. After intratumoral or intravenous injection, CMV-AQP1 could upregulate AQP1 expression and induce DWI SI and ADC alteration in both telomerase-positive and -negative tumors, while hTERT-AQP1 worked in telomerase-positive tumors specifically. CONCLUSION: Cancers can be specifically visualized based on the DWI signal alteration which triggered by hTERT-AQP1 lentivirus system that combined AQP1 gene and hTERT promoter.


Assuntos
Infecções por Citomegalovirus , Neoplasias , Telomerase , Animais , Aquaporina 1/genética , Aquaporina 1/metabolismo , Linhagem Celular Tumoral , Infecções por Citomegalovirus/genética , Humanos , Camundongos , Camundongos Nus , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Regiões Promotoras Genéticas , Telomerase/genética , Telomerase/metabolismo
17.
Drug Des Devel Ther ; 16: 4411-4428, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36597444

RESUMO

Purpose: The use of ketamine, an anesthetic, as a treatment for asthma has been investigated in numerous studies. However, how ketamine affects asthma is unclear. The present study examined the effects of ketamine on a murine model of mixed-granulocytic asthma, and the role of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Methods: The murine model of mixed-granulocytic asthma was established using ovalbumin (OVA) for sensitization and the combination of OVA and lipopolysaccharides (LPS) for challenge. The main characteristics of asthma, oxidative stress biomarkers, and the expression of the Nrf2 pathway were examined. ML385 was administered to verify the role of the Nrf2 pathway. Results: Mice in the OVA +LPS group developed asthmatic characteristics, including airway hyperresponsiveness, mixed-granulocytic airway inflammation, mucus overproduction, as well as increased levels of oxidative stress and impaired apoptosis of inflammatory cells. Among the three concentrations, ketamine at 75mg/kg effectively attenuated these asthmatic symptoms, activated the Nrf2 pathway, decreased oxidative stress, and induced apoptosis of eosinophils and neutrophils in bronchoalveolar lavage fluid (BALF) with a reducing level of myeloid cell leukemia 1(Mcl-1). ML385 (an Nrf2 inhibitor) eliminated the protective effects of ketamine on the mixed-granulocytic asthma model. Conclusion: The study concluded that ketamine reduced oxidative stress and attenuated asthmatic symptoms (neutrophilic airway inflammation) by activating the Nrf2-Keap1 pathway, with 75 mg/kg ketamine showing the best results. Ketamine administration also increased neutrophil and eosinophil apoptosis in BALF, which may contribute to the resolution of inflammation. The use of ketamine as a treatment for asthma may therefore be beneficial.


Assuntos
Asma , Ketamina , Animais , Camundongos , Ketamina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Lipopolissacarídeos/farmacologia , Modelos Animais de Doenças , Asma/tratamento farmacológico , Asma/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Líquido da Lavagem Broncoalveolar , Ovalbumina , Camundongos Endogâmicos BALB C , Pulmão
18.
Artigo em Inglês | MEDLINE | ID: mdl-34484386

RESUMO

Methamphetamine (Meth) is a highly addictive substance and the largest drug threat across the globe. There is evidence to indicate that Meth use has serious damage on central nervous system (CNS) and heart in several animal and human studies. However, the connection in the process of Meth addiction between these two systems has not been determined. Emerging data suggest that extracellular vesicles (EVs) carrying behavior-altering microRNA (miRNAs) play a crucial role in cell communication between CNS and peripheral system. Rhynchophylline (Rhy), an antiaddictive alkaloid, was used to protect the brain and heart from Meth-induced damage, which has caught our attention. Here, we used Meth-dependent conditioned place preference (CPP) animal model and cell model to verify the protective effect of Rhy-treated EVs. Further, small RNA sequencing analysis, qPCR, dual-luciferase reporter assay, and transfection test were used to identify the key EVs-encapsulated miRNAs, isolated from cultured H9c2 cells with different treatments, involved in the therapeutic effect and the underlying mechanisms of Rhy. The results demonstrate that Rhy-treated EVs exert protective effects against Meth dependence through the pathway of miR-183-5p-neuregulin-1 (NRG1). Our collective findings provide novel insights into the roles of EVs miRNAs in Meth addiction and support their potential application in the development of novel therapeutic approaches.

19.
Int J Nanomedicine ; 16: 6383-6394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34556986

RESUMO

BACKGROUND: Satisfactory prognosis of breast cancer (BC) is limited by difficulty in early diagnosis and insufficient treatment. The combination of molecular imaging and photothermal therapy (PTT) may provide a solution. METHODS: Fe3O4-Aushell nanoparticles (NPs) were prepared by thermal decomposition, seeded growth and galvanic replacement and were comprehensively characterized. After conjugated to PEG, NPs were used as MRI and PTT agents in vitro and in vivo. RESULTS: Fe3O4-Aushell NPs which had uniform Janus-like morphology were successfully synthesized. The Fe3O4 had a size of 18 ± 2.2 nm, and the Aushell had an outer diameter of 25 ± 3.3 nm and an inner diameter of 20 ± 2.9 nm. The NPs showed superparamagnetism, a saturation magnetization of 36 emu/g, and an optical absorption plateau from 700 to 808 nm. The Fe3O4-Aushell NPs were determined to possess good biocompatibility. After PEG coating, the zeta potential of NPs was changed from -23.75 ± 1.37 mV to -13.93 ± 0.55 mV, and the FTIR showed the characteristic C-O stretching vibration at 1113 cm-1. The NPs' MR imaging implied that the T2 can be shortened by Fe3O4-Aushell NPs in a concentration-dependent manner, and the Fe3O4-Aushell NPs coated with PEG at the molar ratio of 160 (PEG: NPs) showed the highest transverse relaxivity (r 2) of 216 mM-1s-1. After irradiation at 0.65 W/cm2 for 5 min, all cells incubated with the Fe3O4-Aushell-PEG160 NPs (Fe: 30 ppm, Au: 70 ppm) died. After administrated intratumorally, Fe3O4-Aushell-PEG160 notably decreased the signal intensity of tumor in T2WI images. Under the same irradiation, the temperature of tumors injected with Fe3O4-Aushell-PEG160 quickly rose to 54.6°C, and the tumors shrank rapidly and were ablated in 6 days. CONCLUSION: Fe3O4-Aushell-PEG NPs show good r 2 and PTT performance and are promising synergistic theranostic agents of MRI and PTT for BC.


Assuntos
Neoplasias da Mama , Nanoestruturas , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Feminino , Humanos , Imageamento por Ressonância Magnética , Terapia Fototérmica , Medicina de Precisão , Nanomedicina Teranóstica
20.
Front Chem ; 9: 675491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996769

RESUMO

Owing to the localized surface plasmon resonance (LSPR), dynamic manipulation of optical properties through the structure evolution of plasmonic nanoparticles has been intensively studied for practical applications. This paper describes a novel method for direct reversible self-assembly and dis-assembly of Au nanoparticles (AuNPs) in water driven by pH stimuli. Using 3-aminopropyltriethoxysilane (APTES) as the capping ligand and pH-responsive agent, the APTES hydrolyzes rapidly in response to acid and then condenses into silicon. On the contrary, the condensed silicon can be broken down into silicate by base, which subsequently deprotonates the APTES on AuNPs. By controlling condensation and decomposition of APTES, the plasmonic coupling among adjacent AuNPs could be reversible tuned to display the plasmonic color switching. This study provides a facile and distinctive strategy to regulate the reversible self-assembly of AuNPs, and it also offers a new avenue for other plasmonic nanoparticles to adjust plasmonic properties via reversible self-assembly.

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