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1.
Gene ; 922: 148544, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38734187

RESUMO

This study introduces an efficient RPA-PfAgo detection system for the MTHFR C677T polymorphism, proposing a potential strategy to simplify the genotyping process. By optimizing recombinase polymerase amplification (RPA) with Pyrococcus furiosus Argonaute (PfAgo) nucleases, we achieved DNA amplification at a constant temperature. The assay was fine-tuned through meticulous primer and guide DNA selection, with optimal conditions established at 2.0 µL of MgAc, a reaction temperature of 42 °C, and a 10-minute reaction time for RPA. Further optimization of the PfAgo cleavage assay revealed the ideal concentrations of MnCl2, guide DNA, molecular beacon probes, the PfAgo enzyme, and the RPA product to maximize sensitivity and specificity. Clinical validation of 20 samples showed 100% concordance with Sanger sequencing, confirming the method's precision. The RPA-PfAgo system is a promising tool for on-site genotyping, with broad applications in personalized medicine and disease prevention.


Assuntos
Técnicas de Genotipagem , Metilenotetra-Hidrofolato Redutase (NADPH2) , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Técnicas de Genotipagem/métodos , Polimorfismo de Nucleotídeo Único , Pyrococcus furiosus/genética , Pyrococcus furiosus/enzimologia , Genótipo , Técnicas de Amplificação de Ácido Nucleico/métodos , Proteínas Argonautas/genética , Recombinases/metabolismo , Recombinases/genética
2.
Biol Direct ; 19(1): 29, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654312

RESUMO

BACKGROUND: Oocyte quality is critical for the mammalian reproduction due to its necessity on fertilization and early development. During aging, the declined oocytes showing with organelle dysfunction and oxidative stress lead to infertility. AMP-activated protein kinase (AMPK) is a serine/threonine protein kinase which is important for energy homeostasis for metabolism. Little is known about the potential relationship between AMPK with oocyte aging. RESULTS: In present study we reported that AMPK was related with low quality of oocytes under post ovulatory aging and the potential mechanism. We showed the altered AMPK level during aging and inhibition of AMPK activity induced mouse oocyte maturation defect. Further analysis indicated that similar with its upstream regulator PKD1, AMPK could reduce ROS level to avoid oxidative stress in oocytes, and this might be due to its regulation on mitochondria function, since loss of AMPK activity induced abnormal distribution, reduced ATP production and mtDNA copy number of mitochondria. Besides, we also found that the ER and Golgi apparatus distribution was aberrant after AMPK inhibition, and enhanced lysosome function was also observed. CONCLUSIONS: Taken together, these data indicated that AMPK is important for the organelle function to reduce oxidative stress during oocyte meiotic maturation.


Assuntos
Proteínas Quinases Ativadas por AMP , Oócitos , Estresse Oxidativo , Animais , Feminino , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Senescência Celular , Mitocôndrias/metabolismo , Oócitos/metabolismo , Organelas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38299282

RESUMO

BACKGROUND: Due to changes in lifestyle and dietary habits, the global population with obesity is increasing gradually, resulting in a significant rise in the number of individuals having obesity. Obesity is caused by an imbalance between energy intake and consumption, leading to excessive fat accumulation, which interferes with normal human metabolism. It is also associated with cardiovascular disease, metabolic syndrome, male reproductive endocrine regulation disorders, systemic and local inflammatory reactions, excessive oxidative stress, and apoptosis. All these factors can damage the internal environment for sperm generation and maturation, resulting in male sexual dysfunction, a decline in sperm quality, and lower fertility. This study analyzes the trends and priorities of the effects of obesity on male reproductive disorders from a bibliometric perspective. METHODS: This study uses the Web of Science as the statistical source, covering all time spans. Tools like Web of Science, VOSviewer, and CiteSpace are used to analyze countries, institutions, authors, journals, and keywords in the field. Total publications, total citations, and average number of citations are selected for statistics. RESULTS: The results show that the research on the impact of obesity on male reproductive function can be roughly divided into three stages: the initial stage, the slow development stage, and the rapid development stage. Our statistical scope includes 463 highly relevant articles that we have screened. We found that the journal with the most publications in this field is Andrologia, and the institution with the highest total citations is the University of Utah. The most influential countries, institutions, and authors in this field are the United States, the University of Utah, and Carrell, Douglas. Currently, research related to the impact of obesity on male reproduction focuses mainly on three aspects: biochemistry, molecular biology, and reproductive biology. The keyword explosion results indicate that sperm, obesity, and male reproduction are at the forefront and trends of future research in this field. There has been a shift from basic biochemical and molecular research to research on molecular mechanisms relying on omics technologies. However, we have observed that the number of papers published in 2022 is lower than in 2021, indicating a growth interruption during this period. Considering that this deviation may be due to the impact of the COVID-19 pandemic, it may hinder the progress of certain experiments in 2022. In recent years, China has rapidly developed research in this field. However, the average citation rate is relatively low, indicating the need for Chinese scholars to improve the quality of their articles further. Based on our research and in the context of global obesity, men are at risk of increased infertility. Addressing this issue relies on our continued research into the mechanisms of obesity-related male reproductive disorders. Over the past forty-three years, with the contributions of scientists worldwide, research in this field has flourished. CONCLUSION: The impact of obesity on male reproductive disorders has been extensively studied. Currently, research in this field primarily focuses on male sperm function, sperm quality, and the effects or mechanisms of cells on male reproduction. Future trends in this field should concentrate on the relationship between male fertility and energy metabolism, as well as the endocrine function of adipose tissue. This study comprehensively analyzes the current research status and global trends in obesity and male reproductive disorders. We also discuss the future developments in this field, making it easier for researchers to understand its developmental history, current status, and trends, providing valuable reference for effective exploration in this area.


Assuntos
Bibliometria , Infertilidade Masculina , Obesidade , Masculino , Humanos , Obesidade/epidemiologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/fisiopatologia , Reprodução/fisiologia
4.
Funct Integr Genomics ; 23(3): 264, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37541978

RESUMO

Liver cancer is a cunning malignancy with a high incidence and mortality rate among cancers worldwide. The NPC gene family members (NPCs: NPC1, NPC2, and NPC1L1) are closely linked to the development of multiple cancers, but their role in liver cancer remains unclear. As a result, we must investigate their functions in liver hepatocellular carcinoma (LIHC). NPCs were significantly differentially expressed between normal and LIHC tissues, with a high mutation frequency in LIHC. The ROC curve analysis revealed that NPC1/NPC2 had high diagnostic and prognostic values in LIHC. NPC1 expression was also found to be negatively correlated with its methylation level. The differentially expressed genes between high and low NPC1 expression groups in LIHC were mainly related to channel activity, transporter complexes, and plasma membrane adhesion molecules. Additionally, NPC1 expression was significantly associated with multiple immune cells and immunization checkpoints. It was hypothesized that a TUG1/SNHG4-miR-148a-3p-NPC1 regulatory axis is associated with hepatocarcinogenesis. Finally, the protein expression of NPC1 in LIHC tissues and paraneoplastic tissues was detected, and NPC1-knockdown HepG2 cells (NPC1KO) inhibited the proliferation, migration, and invasion. This study helped to identify new prognostic markers and potential immunotherapeutic targets for LIHC and revealed the molecular mechanisms underlying NPC1 regulation in LIHC. The NPCs play a key role in the prognosis and diagnosis of LIHC and may be an important indicator for LIHC prognosis and diagnosis; NPC1 might be a potential therapeutic target in LIHC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Prognóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Multiômica
5.
CNS Neurosci Ther ; 29(3): 917-931, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36382345

RESUMO

AIMS: Cerebrovascular impairment contributes to the pathogenesis of Alzheimer's disease (AD). However, it still lacks effective intervention in clinical practice. Here, we investigated the efficacy of electroacupuncture (EA) in cerebrovascular repair in 3xTg-AD mice and its mechanism. METHODS: 3xTg-AD mice were employed to evaluate the protective effect of EA at ST36 acupoint (EAST36). Behavioral tests were performed to assess neurological disorders. Laser speckle contrast imaging, immunostaining, and Western blot were applied to determine EAST36-boosted cerebrovascular repair. The mechanism was explored in 3xTg mice and endothelial cell cultures by melatonin signaling modulation. RESULTS: EAST36 at 20/100 Hz effectively alleviated the olfactory impairment and anxiety behavior and boosted cerebrovascular repair in AD mice. EAST36 attenuated cerebral microvascular degeneration in AD mice by modulating endothelial cell viability and injury. Consequently, the Aß deposits and neural damage in AD mice were reversed after EAST36. Mechanistically, we revealed that EAST36 restored melatonin levels in AD mice. Melatonin supplement mimicked the EAST36 effect on cerebrovascular protection in AD mice and endothelial cell cultures. Importantly, blockage of melatonin signaling by antagonist blunted EAST36-induced cerebrovascular recovery and subsequent neurological improvement. CONCLUSIONS: These findings provided strong evidence to support EAST36 as a potential nonpharmacological therapy against cerebrovascular impairment in AD. Further study is necessary to better understand how EAST36 treatment drives melatonin signaling.


Assuntos
Doença de Alzheimer , Eletroacupuntura , Melatonina , Camundongos , Animais , Doença de Alzheimer/terapia , Doença de Alzheimer/tratamento farmacológico , Melatonina/uso terapêutico , Eletroacupuntura/métodos , Modelos Animais de Doenças , Camundongos Transgênicos
6.
Zhen Ci Yan Jiu ; 47(6): 497-503, 2022 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-35764516

RESUMO

OBJECTIVE: To investigate the protective effect of electroacupuncture (EA) at "Zusanli"(ST36)and "Weiwanxiashu"(EX-B3) on capillary function around the renal tubule and renal tubule structure in diabetic mice based on two-photon microscopy (TPM) imaging, so as to providing visualizable evidence for the regulatory effect of EA on diabetic renal vascular microcirculation. METHODS: Spontaneous type Ⅱ diabetes mellitus mice (db/db) were employed for this study. Twenty db/db mice were randomly divided into model group (n=10) and EA group (n=10), and 10 db/m mice used as the control group. EA was applied to bilateral ST36 and EX-B3 for 20 min/time, 6 times a week for 6 weeks. The body weight was recorded and the fasting blood glucose measured before and after the intervention. The urine production and water consumption of mice in each cage were recorded after EA. The renal in vivo imaging method based on TPM was established to display the morphological structure of renal tubules, and the mouse renal blood flow velocity was detected by injecting 500 kDa dextran-fluorescein into femoral vein after the intervention. RESULTS: Compared with the control group, the proportion of mice with decreased body mass in the model group was increased, accounting for 40%, while that in the control group was 0%; and fasting blood glucose, urine production and water consumption were significantly increased in the model group (P<0.001, P<0.000 1). A renal in vivo imaging method based on TPM was successfully established, which can be applied to quantitatively analyze the renal blood flow and renal tubular diameter of mice. Based on this method, the results showed that compared with the control group, the blood flow velocity of peritubular capillary in the model group was significantly decreased (P<0.000 1, P<0.001), renal tubular cells were slightly exfoliated and the diameter of renal tubular was significantly increased (P<0.000 1). Compared with the model group, EA reduced the body weight loss ratio from 40% to 0%, and significantly decreased the fasting blood glucose, urine production and water consumption (P<0.01, P<0.000 1, P<0.001), and the blood flow velocity of peritubular capillary in the EA group was significantly increased (P<0.001, P<0.05) and tubule dilatation significantly alleviated (P<0.0 1). CONCLUSION: EA at ST36 and EX-B3 can ameliorate renal vascular microcirculation disorder to relieve the renal structure damage and improve renal function in diabetes mice.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Eletroacupuntura , Animais , Glicemia , Diabetes Mellitus Experimental/diagnóstico por imagem , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/terapia , Camundongos , Microcirculação , Microscopia
7.
Theranostics ; 12(6): 2549-2559, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401818

RESUMO

Background: Imaging amyloid-beta (Aß) deposits with high fidelity in naturally aging brains is crucial for the early diagnosis of Alzheimer's disease (AD). However, this is impeded by the lack of highly sensitive probes. Methods: By conducting computational modelling to quantitatively fine-tune the twisted intramolecular charge transfer (TICT) tendency of Thioflavin T (ThT) analogues, we developed an ultrasensitive probe AH-2. AH-2 retained the binding affinity and binding mode of ThT towards Aß deposits, and exhibited ca 10-fold less background fluorescence and 5-10 folds of improved signal-to-background contrast upon binding Aß deposits. These desirable features endowed AH-2 the sensitivity to detect Aß deposition in naturally aging wild-type mice. Results: AH-2 imaging revealed that Aß puncta signals appeared near the nuclei in young mice and spread through the intracellular and extracellular compartments in older mice. Moreover, Aß deposits were observed to emerge earlier in mice cerebral cortex than in the hippocampus region. Given this desirable sensitivity and good spatiotemporal resolution, AH-2 was successfully applied in the preclinical evaluation of Aß-targeted treatment by melatonin. Conclusions: We expect that AH-2 is promising for early diagnosis of AD and will serve as a sensitive tool for studying Aß-related AD pathology.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Diagnóstico Precoce , Corantes Fluorescentes/química , Camundongos , Camundongos Transgênicos , Imagem Óptica/métodos
8.
Opt Lett ; 47(7): 1754-1757, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363727

RESUMO

We experimentally investigate image reconstruction through a scattering medium under white-light illumination. To solve the inverse problem of noninvasive scattering imaging, a modified iterative algorithm is employed with an interpretable constraint on the optical transfer function (OTF). As a result, a sparse and real object can be retrieved whether it is illuminated with a narrowband or broadband light. Compared with the well-known speckle correlation technique (SCT), the proposed method requires no restrictions on the speckle autocorrelation and shows a potential advantage in scattering imaging.

9.
Anal Chem ; 94(2): 1308-1317, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34962779

RESUMO

Alterations in formaldehyde (FA) homeostasis are associated with the pathology of Alzheimer's disease (AD). In vivo tracking of FA flux is important for understanding the underlying molecular mechanisms, but is challenging due to the lack of sensitive probes favoring a selective, rapid, and reversible response toward FA. In this study, we re-engineered the promiscuous and irreversible phenylhydrazines to make them selective and reversible toward FA by tuning their nucleophilicity. This effort resulted in PFM309, a selective (selectivity coefficient KFA,methylglyoxal = 0.06), rapid (t1/2 = 32 s at [FA] = 200 µM), and reversible fluorogenic probe (K = 6.24 mM-1) that tracks the FA flux in both live cells and live mice. In vivo tracking of the FA flux was realized by PFM309 imaging, which revealed the gradual accumulation of FA in the live mice brain during normal aging and its further increase in AD mice. We further identified the age-dependent loss of catabolism enzymes ALDH2 and ADH5 as the primary mechanism responsible for formaldehyde excess. Activating ALDH2 with the small molecular activator Alda1 significantly protected neurovascular cells from formaldehyde overload and consequently from impairment during AD progress both in vitro and in vivo. These findings revealed PFM309 as a robust tool to study AD pathology and highlight ALDH2 as a potential target for AD drug development.


Assuntos
Doença de Alzheimer , Envelhecimento , Aldeído-Desidrogenase Mitocondrial/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Animais , Formaldeído/metabolismo , Camundongos
10.
Opt Lett ; 46(23): 5954-5957, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34851932

RESUMO

The shape of two objects hidden behind a thin scattering medium is retrieved by the presented method. One of the two objects keeps stationary, while the other one is supposed to be gradually moving, and the Euclidean distance between them is always beyond the range of the 3D optical memory effect. We capture two speckle patterns to image the two isolated objects by using a developed speckle-differential-based strategy and the traditional speckle autocorrelation technique. The feasibility of our method is demonstrated by theoretical analysis and a set of experiments.

11.
Opt Express ; 29(24): 40091-40105, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809358

RESUMO

Non-line-of-sight (NLOS) imaging has received considerable attentions for its ability to recover occluded objects from an indirect view. Various NLOS imaging techniques have been demonstrated recently. Here, we propose a white-light NLOS imaging method that is equipped only with an ordinary camera, and not necessary to operate under active coherent illumination as in other existing NLOS systems. The central idea is to incorporate speckle correlation-based model into a deep neural network (DNN), and form a two-step DNN strategy that endeavors to learn the optimization of the scattered pattern autocorrelation and object image reconstruction, respectively. Optical experiments are carried out to demonstrate the proposed method.

12.
Opt Express ; 29(12): 18807-18816, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34154129

RESUMO

A speckle image formed by scattering lights can be decoded by recently invented techniques, owing to the optical memory effect, thereby enabling the observation of a hidden object behind a thin scattering medium. However, the range of three-dimensional OME is typically small; therefore, both the field of view and depth of field are limited. We propose a method that can significantly and simultaneously improve both values for a specific scenario, where one object moves around the other position-fixed object. The effectiveness of the proposed scheme is demonstrated through a set of experiments.

13.
Sci Rep ; 9(1): 18248, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796756

RESUMO

Vascular dementia (VaD) is a complex disorder caused by reduced blood flow in the brain. However, there is no effective pharmacological treatment option available until now. Here, we reported that low-dose levamlodipine besylate could reverse the cognitive impairment in VaD mice model of right unilateral common carotid arteries occlusion (rUCCAO). Oral administration of levamlodipine besylate (0.1 mg/kg) could reduce the latency to find the hidden platform in the MWM test as compared to the vehicle group. Furthermore, vehicle-treated mice revealed reduced phospho-CaMKII (Thr286) levels in the hippocampus, which can be partially restored by levamlodipine besylate (0.1 mg/kg and 0.5 mg/kg) treatment. No significant outcome on microglia and astrocytes were observed following levamlodipine besylate treatment. This data reveal novel findings of the therapeutic potential of low-dose levamlodipine besylate that could considerably enhance the cognitive function in VaD mice.


Assuntos
Anlodipino/administração & dosagem , Demência Vascular/tratamento farmacológico , Niacina/análogos & derivados , Nootrópicos/administração & dosagem , Anlodipino/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Vasos Sanguíneos/efeitos dos fármacos , Modelos Animais de Doenças , Camundongos , Microglia/efeitos dos fármacos , Niacina/administração & dosagem , Niacina/uso terapêutico , Nootrópicos/farmacologia
14.
Opt Express ; 27(15): 21204-21213, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510202

RESUMO

Random Phase Encoding (RPE) techniques for image encryption have drawn increasing attention during the past decades. We demonstrate in this contribution that the RPE-based optical cryptosystems are vulnerable to the chosen-plaintext attack (CPA) with deep learning strategy. A deep neural network (DNN) model is employed and trained to learn the working mechanism of optical cryptosystems, and finally obtaining a certain optimized DNN that acts as a decryption system. Numerical simulations were carried out to verify its feasibility and reliability of not only the classical Double RPE (DRPE) scheme but also the security-enhanced Tripe RPE (TRPE) scheme. The results further indicate the possibility of reconstructing images (plaintexts) outside the original data set.

15.
Opt Express ; 27(9): 13469-13478, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31052868

RESUMO

A compressive optical steganography based on single-pixel imaging (SPI) is proposed. The SPI system, which employs a digital light projector to illuminate the host image with modulated patterns, is similar to a wireless broadcast system. Therefore, it is suitable for covert communication naturally. By leveraging the compressive sensing technique and a generalized phase retrieval algorithm, the secret message is sparse-sampled and then encoded into the illumination patterns, which are projected onto the host image in an SPI architecture. The resulting reflected light signals travel in the free space as a broadcast system, and the signals would be captured by the authorized receivers and the potential eavesdroppers. By implementing an inverse Fourier transform, a stegoimage will be received, which is almost the same as the host image. However, only the authorized receivers, who possess the secret key, could extract the desired data from the stegoimage and then reconstruct the secret message by using a convex optimization algorithm. Because the secret message is sparse-sampled before embedding, the imperceptibility is well preserved while the capacity also be kept in a high level. A series of simulation and experimental results verifies the validity and feasibility of the proposed method.

16.
Sci Rep ; 9(1): 7165, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31073149

RESUMO

Large depth of field (DOF) is a longstanding goal in optical imaging field. In this paper we presented a simple but efficient method to extend the DOF of a diffraction-limited imaging system using a thin scattering diffuser. The DOF characteristic of the imaging system with random phase modulation was analyzed based on the analytical model of ambiguity function as a polar display of the optical transfer function (OTF). The results of numerical simulation showed that more high-frequency components existed in the defocused OTF curve when the exit pupil of the imaging system exhibited a random phase modulation. It proved the important role of the scattering diffuser in extending the DOF of imaging systems. For the reconstruction, a stack of point spread functions (PSFs) corresponding to different axial locations within a measurement range were superimposed to construct the stacked PSF. Then the large DOF image was recovered from a speckle pattern by deconvolution. In this proof-of-concept, we experimentally demonstrated the single-shot imaging with larger DOF using a thin glass scattering diffuser in both a single-lens imaging system and a microscopic imaging system.

17.
Appl Opt ; 58(2): 473-478, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30645330

RESUMO

Speckle correlation imaging (SCI) has been considered one of the most promising techniques for computational imaging through a scattering medium. However, the image quality is not always acceptable in conventional SCI, especially when a complex object is involved. In this work, a modified phase retrieval algorithm is introduced to significantly improve the imaging quality of SCI. In the proposed scheme, nonzero-pixel constraints, rather than the real and nonnegative constraints, are employed as the object domain constraints of the iterative algorithm in the image reconstruction process. Experimental results are presented to show the performance enhancement of this scheme, inclusive of less iterations, better image quality, and higher reliability, in comparison with the conventional SCI method.

18.
Antioxid Redox Signal ; 27(16): 1297-1316, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28292196

RESUMO

AIMS: Dysfunction of neurovascular pericytes underlies breakdown of the blood-brain barrier, but the molecular mechanisms are largely unknown. In this study, we evaluated the role of the transient receptor potential melastatin-related 2 (TRPM2) channel and autophagy during brain pericyte injury both in vitro and in vivo. RESULTS: A rapid induction in autophagy in human brain vascular pericytes, in the zinc oxide nanoparticles (ZnO-NP)-induced cell stress model, was paralleled with an increase in the expression of the TRPM2-S truncated isoform, which was abolished by treatment with a nitric oxide synthase inhibitor and a peroxynitrite scavenger. Furthermore, Y1485 in the C-terminus of the TRPM2 protein was identified as the tyrosine nitration substrate by mass spectrometry. Overexpression of the Y1485S TRPM2 mutant reduced LC3-II accumulation and pericyte injury induced by ZnO-NP. Consistently, LC3-II accumulation was reduced and pericytes were better preserved in intact brain microvessels of the TRPM2 knockout mice after ZnO-NP-induced vascular injury. Innovation and Conclusions: Our present study has revealed a novel mechanism of autophagy disturbance secondary to nitrosative stress-induced tyrosine nitration of TRPM2 during pericyte injury. Antioxid. Redox Signal. 27, 1297-1316.


Assuntos
Lesões Encefálicas/metabolismo , Estresse Nitrosativo , Canais de Cátion TRPM/química , Canais de Cátion TRPM/metabolismo , Tirosina/química , Óxido de Zinco/efeitos adversos , Animais , Autofagia , Barreira Hematoencefálica , Lesões Encefálicas/genética , Células Cultivadas , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Humanos , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Nanopartículas/química , Pericitos , Canais de Cátion TRPM/genética
19.
Sci Rep ; 7: 41789, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28139729

RESUMO

Security analysis is important and necessary for a new cryptosystem. In this paper, we evaluate the security risk of the optical cryptosystem with spatially incoherent illumination from the view of imaging through scattering medium and then demonstrate that it is vulnerable to ciphertext-only attack. The proposed ciphertext-only attack method relies on the optical memory effect for speckle correlations, which reveals a fact that the ciphertext's autocorrelation is essentially identical to the plaintext's own autocorrelation. Furthermore, by employing of an improved dynamic hybrid input-output phase-retrieval algorithm, we show that a plaintext image can be directly reconstructed from the autocorrelation of its corresponding ciphertext without any prior knowledge about the plaintext or the phase keys. Meanwhile, the theory analysis and experiment results will also be provided to verify the validity and feasibility of our proposed ciphertext-only attack method. To the best of our knowledge, this is the first time to report optical cryptanalysis from the point of view of imaging through scattering medium and we believe this contribution will open up an avenue to deepen the investigation of optical cryptosystems.

20.
ACS Appl Mater Interfaces ; 8(51): 35045-35058, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27750011

RESUMO

Clinical treatment for vascular dementia still remains a challenge mainly due to the blood-brain barrier (BBB). Here, a micelle based on polysialic acid (PSA), which is a hydrophilic and endogenous carbohydrate polymer, was designed to deliver calmodulin antagonist for therapy of vascular dementia. PSA was first chemically conjugated with octadecylamine (ODA), and the obtained PSA-ODA copolymer could self-assemble into micelle in aqueous solution with a 120.0 µg/mL critical micelle concentration. The calmodulin antagonist loaded PSA-ODA micelle, featuring sustained drug release behavior over a period of 72 h with a 3.6% (w/w) drug content and a 107.0 ± 4.0 nm size was then fabricated. The PSA-ODA micelle could cross the BBB mainly via active endocytosis by brain endothelial cells followed by transcytosis. In a water maze test for spatial learning, calmodulin antagonist loaded PSA-ODA micelle significantly reduced the escape latencies of right unilateral common carotid arteries occlusion (rUCCAO) mice with dosage significantly reduced versus free drug. The decrease of hippocampal phospho-CaMKII (Thr286/287) and phospho-synapsin I (Ser603) was partially restored in rUCCAO mice following calmodulin antagonist loaded PSA-ODA micelle treatment. Consistent with the restored CaMKII phosphorylation, the elevation of BrdU/NeuN double-positive cells in the same context was also observed. Overall, the PSA-ODA micelle developed from the endogenous material might promote the development of therapeutic approaches for improving the efficacy of brain-targeted drug delivery and have great potential for vascular dementia treatment.


Assuntos
Ácidos Siálicos/química , Animais , Calmodulina , Demência Vascular , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Camundongos , Micelas , Polímeros
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