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1.
FASEB J ; 38(7): e23565, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38558188

RESUMO

Circadian rhythms in metabolically active tissues are crucial for maintaining physical health. Circadian disturbance (CD) can cause various health issues, such as metabolic abnormalities and immune and cognitive dysfunctions. However, studies on the role of CD in immune cell development and differentiation, as well as the rhythmic expression of the core clock genes and their altered expression under CD, remain unclear. Therefore, we exposed C57bl/6j mice to repeated reversed light-dark cycles for 90 days to research the effects of CD on bone marrow (BM) hematopoietic function. We also researched the effects of CD on endogenous circadian rhythms, temporally dependent expression in peripheral blood and myeloid leukocytes, environmental homeostasis within BM, and circadian oscillations of hematopoietic-extrinsic cues. Our results confirmed that when the light and dark cycles around mice were frequently reversed, the circadian rhythmic expression of the two main circadian rhythm markers, the hypothalamic clock gene, and serum melatonin, was disturbed, indicating that the body was in a state of endogenous CD. Furthermore, CD altered the temporally dependent expression of peripheral blood and BM leukocytes and destroyed environmental homeostasis within the BM as well as circadian oscillations of hematopoietic-extrinsic cues, which may negatively affect BM hematopoiesis in mice. Collectively, these results demonstrate that circadian rhythms are vital for maintaining health and suggest that the association between CD and hematopoietic dysfunction warrants further investigation.


Assuntos
Medula Óssea , Relógios Circadianos , Camundongos , Animais , Medula Óssea/metabolismo , Fotoperíodo , Ritmo Circadiano/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Camundongos Endogâmicos C57BL , Relógios Circadianos/genética
2.
Anal Chim Acta ; 1302: 342494, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38580414

RESUMO

BACKGROUND: Thrombin, a coagulation system protease, is a key enzyme involved in the coagulation cascade and has been developed as a marker for coagulation disorders. However, the methods developed in recent years have the disadvantages of complex operation, long reaction time, low specificity and sensitivity. Meanwhile, thrombin is at a lower level in the pre-disease period. Therefore, to accurately diagnose the disease, it is necessary to develop a fast, simple, highly sensitive and specific method using signal amplification technology. RESULTS: We designed an electrochemical biosensor based on photocatalytic atom transfer radical polymerization (photo-ATRP) signal amplification for the detection of thrombin. Sulfhydryl substrate peptides (without carboxyl groups) are self-assembled to the gold electrode surface via Au-S bond and serve as thrombin recognition probes. The substrate peptide is cleaved in the presence of thrombin to generate -COOH, which can form a carboxylate-Zr(IV)-carboxylate complex via Zr(IV) and initiator (α-bromophenylacetic acid, BPAA). Subsequently, an electrochemical biosensor was prepared by introducing polymer chains with electrochemical signaling molecules (ferrocene, Fc) onto the electrode surface by photocatalytic (perylene, Py) mediated ATRP using ferrocenylmethyl methacrylate (FMMA) as a monomer. The concentration of thrombin was evaluated by the voltammetric signal generated by square wave voltammetry (SWV), and the result showed that the biosensor was linear between 1.0 ng/mL âˆ¼ 10 fg/mL, with a lower detection limit of 4.0 fg/mL (∼0.1 fM). Moreover, it was shown to be highly selective for thrombin activity in complex serum samples and for thrombin inhibition screening. SIGNIFICANCE: The biosensor is an environmentally friendly and economically efficient strategy while maintaining the advantages of high sensitivity, anti-interference, good stability and simplicity of operation, which has great potential for application in the analysis of complex samples.


Assuntos
Técnicas Biossensoriais , Perileno , DNA/química , Trombina , Polimerização , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Peptídeos , Limite de Detecção
3.
Biogerontology ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38109001

RESUMO

Of the factors studied in individual ageing, the accumulation of senescent cells has been considered as an essential cause of organ degeneration to eventually initiate age-related diseases. Cellular senescence is attributed to the accumulation of damage for an inducement in the activation of cell cycle inhibitory pathways, resulting the cell permanently withdraw from the cell proliferation cycle. Further, senescent cells will activate the inflammatory factor secretion pathway to promote the development of various age-related diseases. Senolytics, a small molecule compound, can delay disease development and extend mammalian lifespan. The evidence from multiple trials shows that the targeted killing of senescent cells has a significant clinical application for the treatment of age-related diseases. In addition, senolytics are also significant for the development of ageing research in solid organ transplantation, which can fully develop the potential of elderly organs and reduce the age gap between demand and supply. We conclude that the main characteristics of cellular senescence, the anti-ageing drug senolytics in the treatment of chronic diseases and organ transplantation, and the latest clinical progress of related researches in order to provide a theoretical basis for the prevention and treatment of ageing and related diseases.

4.
Brain Behav Immun ; 114: 221-239, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37648006

RESUMO

Epidemiological investigations show that noise exposure in early life is associated with health and cognitive impairment. The gut microbiome established in early life plays a crucial role in modulating developmental processes that subsequently affect brain function and behavior. Here, we examined the impact of early-life exposure to noise on cognitive function in adolescent rats by analyzing the gut microbiome and metabolome to elucidate the underlying mechanisms. Chronic noise exposure during early life led to cognitive deficits, hippocampal injury, and neuroinflammation. Early-life noise exposure showed significant difference on the composition and function of the gut microbiome throughout adolescence, subsequently causing axis-series changes in fecal short-chain fatty acid (SCFA) metabolism and serum metabolome profiles, as well as dysregulation of endothelial tight junction proteins, in both intestine and brain. We also observed sex-dependent effects of microbiota depletion on SCFA-related beneficial bacteria in adolescence. Experiments on microbiota transplantation and SCFA supplementation further confirmed the role of intestinal bacteria and related SCFAs in early-life noise-exposure-induced impairments in cognition, epithelial integrity, and neuroinflammation. Overall, these results highlight the homeostatic imbalance of microbiota-gut-brain axis as an important physiological response toward environmental noise during early life and reveals subtle differences in molecular signaling processes between male and female rats.


Assuntos
Disfunção Cognitiva , Microbioma Gastrointestinal , Masculino , Feminino , Ratos , Animais , Eixo Encéfalo-Intestino , Doenças Neuroinflamatórias , Microbioma Gastrointestinal/fisiologia , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/farmacologia , Homeostase
5.
Front Cell Infect Microbiol ; 13: 1067367, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37180445

RESUMO

Background: Environmental noise exposure is linked to neuroinflammation and imbalance of the gut microbiota. Promoting gut microbiota homeostasis may be a key factor in relieving the deleterious non-auditory effects of noise. This study aimed to investigate the effect of Lactobacillus rhamnosus GG (LGG) intervention on noise-induced cognitive deficits and systemic inflammation in rats. Methods: Learning and memory were assessed using the Morris water maze, while 16S rRNA sequencing and gas chromatography-mass spectrometry were used to analyze the gut microbiota and short-chain fatty acid (SCFA) content. Endothelial tight junction proteins and serum inflammatory mediators were assessed to explore the underlying pathological mechanisms. Results: The results indicated that Lactobacillus rhamnosus GG intervention ameliorated noise-induced memory deterioration, promoted the proliferation of beneficial bacteria, inhibited the growth of harmful bacteria, improved dysregulation of SCFA-producing bacteria, and regulated SCFA levels. Mechanistically, noise exposure led to a decrease in tight junction proteins in the gut and hippocampus and an increase in serum inflammatory mediators, which were significantly alleviated by Lactobacillus rhamnosus GG intervention. Conclusion: Taken together, Lactobacillus rhamnosus GG intervention reduced gut bacterial translocation, restored gut and blood-brain barrier functions, and improved gut bacterial balance in rats exposed to chronic noise, thereby protecting against cognitive deficits and systemic inflammation by modulating the gut-brain axis.


Assuntos
Lacticaseibacillus rhamnosus , Probióticos , Ratos , Animais , Eixo Encéfalo-Intestino , RNA Ribossômico 16S , Inflamação/metabolismo , Proteínas de Junções Íntimas , Mediadores da Inflamação , Cognição , Probióticos/uso terapêutico
6.
Cells ; 11(17)2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36078149

RESUMO

Environmental noise is a common hazard in military operations. Military service members during long operations are often exposed to around-the-clock noise and suffer massive emotional and cognitive dysfunction related to an Alzheimer's disease (AD)-like neuropathology. It is essential to clarify the mechanisms underlying the effects of around-the-clock noise exposure on the central nervous system. Here, Wistar rats were continuously exposed to white noise (95 dB during the on-duty phase [8:00-16:00] and 75 dB during the off-duty phase (16:00-8:00 the next day)) for 40 days. The levels of phosphorylated tau, amyloid-ß (Aß), and neuroinflammation in the cortex and hippocampus were assessed and autophagosome (AP) aggregation was observed by transmission electron microscopy. Dyshomeostasis of autophagic flux resulting from around-the-clock noise exposure was assessed at different stages to investigate the potential pathological mechanisms. Around-the-clock noise significantly increased Aß peptide, tau phosphorylation at Ser396 and Ser404, and neuroinflammation. Moreover, the AMPK-mTOR signaling pathway was depressed in the cortex and the hippocampus of rats exposed to around-the-clock noise. Consequently, autophagosome-lysosome fusion was deterred and resulted in AP accumulation. Our results indicate that around-the-clock noise exposure has detrimental influences on autophagic flux homeostasis and may be associated with AD-like neuropathology in the cortex and the hippocampus.


Assuntos
Autofagia , Doenças do Sistema Nervoso , Ruído , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Autofagia/fisiologia , Homeostase , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/patologia , Ruído/efeitos adversos , Ratos , Ratos Wistar
7.
Front Cell Dev Biol ; 10: 994001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176279

RESUMO

Fatigue results from a series of physiological and psychological changes due to continuous energy consumption. It can affect the physiological states of operators, thereby reducing their labor capacity. Fatigue can also reduce efficiency and, in serious cases, cause severe accidents. In addition, it can trigger pathological-related changes. By establishing appropriate methods to closely monitor the fatigue status of personnel and relieve the fatigue on time, operation-related injuries can be reduced. Existing fatigue detection methods mostly include subjective methods, such as fatigue scales, or those involving the use of professional instruments, which are more demanding for operators and cannot detect fatigue levels in real time. Speech contains information that can be used as acoustic biomarkers to monitor physiological and psychological statuses. In this study, we constructed a fatigue model based on the method of sleep deprivation by collecting various physiological indexes, such as P300 and glucocorticoid level in saliva, as well as fatigue questionnaires filled by 15 participants under different fatigue procedures and graded the fatigue levels accordingly. We then extracted the speech features at different instances and constructed a model to match the speech features and the degree of fatigue using a machine learning algorithm. Thus, we established a method to rapidly judge the degree of fatigue based on speech. The accuracy of the judgment based on unitary voice could reach 94%, whereas that based on long speech could reach 81%. Our fatigue detection method based on acoustic information can easily and rapidly determine the fatigue levels of the participants. This method can operate in real time and is non-invasive and efficient. Moreover, it can be combined with the advantages of information technology and big data to expand its applicability.

8.
Small ; 18(13): e2107364, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35143716

RESUMO

It is highly desired but still remains challenging to design a primary explosive-based nanoparticle-encapsulated conductive skeleton for the development of powerful yet safe energetic films employed in miniaturized explosive systems. Herein, a proof-of-concept electrochemical preparation of metal-organic frameworks (MOFs) derived porous carbon embedding copper-based azide (Cu(N3 )2 or CuN3 , CA) nanoparticles on copper substrate is described. A Cu-based MOF, i.e., Cu-BTC is fabricated based on anodized Cu(OH)2 nanorods, as a template, to achieve CA/C film through pyrolysis and electrochemical azidation. Such a CA/C film, which is woven by numerous ultrafine nanofibers, favorably demonstrates excellent energy release (945-2090 J g-1 ), tunable electrostatic sensitivity (0.22-1.39 mJ), and considerable initiation ability. The performance is superior to most reported primary explosives, since the CA nanoparticles contribute to high brisance and the protection of the porous carbon network. Notably, the growth mechanism of the CA/C film is further disclosed by detailed experimental investigation and density functional theory (DFT) calculation. This work will offer new insight to design and develop a CA-based primary explosive film for applications in advanced explosive systems.

9.
Prep Biochem Biotechnol ; 52(9): 1035-1043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35015605

RESUMO

Enzyme immobilization provides ideal operating conditions for enzymes stabilization and sustainable recycling. In this work, as a kind of clay material, montmorillonite (MTL) was chosen for immobilizing the ß-glucosidase extracted from Agrocybe aegirit. The immobilized ß-glucosidase via partly cross-linking enzyme aggregates (pCLEAs) formed by self-catalysis provided biocatalysts with satisfactory thermal and pH stability. Compared to the glutaraldehyde cross-linked, the immobilized ß-glucosidase (ß-G-pCLEAs@MTL) exhibited significantly higher immobilization efficiency (IE) and immobilization yield (IY), which were 80.6% and 76.9%, respectively. The ß-G-pCLEAs@MTL also showed better stability and preferable reusability. And the activity of the ß-G-pCLEAs@MTL remained 85.0% after 5 cycles and 74.7% after 10 cycles. Therefore, the method based on the pre- crosslinking to form pCLEAs and after-immobilization can effectively improve IY and IE. In addition, MTL seems to be a good alternative carrier to immobilize other enzymes for industrial application.


Assuntos
Bentonita , Enzimas Imobilizadas , Argila , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Glutaral , Concentração de Íons de Hidrogênio , Temperatura , beta-Glucosidase/metabolismo
10.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(5): 491-496, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37088758

RESUMO

OBJECTIVE: To investigate the effects of glutamate aspartate transporter (GLAST)deletion on the normal auditory function of mice. METHODS: We hybridized GLAST+/- mice with C57BL/6J background and identified the genotypes of their offspring by agarose gel electrophoresis. 9-10-week-old mice were selected to detect the expression of GLAST protein in the cochlea by immunofluorescence staining and to verify the knockout results(n=3). The changes in weight from 7 days to 30 days after birth and the 30-day body length of male and female mice were compared(n=8). The auditory brainstem response(ABR) was used to detect the auditory threshold and the amplitude of wave I in 9-10-week-old male and female mice(n=5). RESULTS: Male GLAST-/- mice had shown significantly lower weight and body length compared to male GLAST+/+ and GLAST+/- mice(P<0.01), and male GLAST-/- mice showed significant differences compared to GLAST+/+ from P7 to P30 statistical time. Male GLAST-/- mice exhibited a significant reduction in weight after P15 compared to male GLAST+/- mice. In contrast, no significant differences in weight and body length were observed in female GLAST-/- mice compared with female GLAST+/+ and GLAST+/- mice. There was no difference in the hearing threshold detected by ABR between the three genotypes in both male and female mice, but the amplitude of wave I in GLAST-/- mice was significantly lower than that in male GLAST+/+ mice(P<0.01). In contrast, the amplitude of wave I in females was reduced throughout the stimulus intensity but was most significant only at high-intensity stimulation (e.g.80 dB, 90 dB) (P<0.05). CONCLUSION: GLAST knockout affects the normal growth and development of male mice, and decreases the amplitude of wave I, but do not change the threshold, suggesting that GLAST knockout may lead to synaptic pathological changes, and there are gender differences in this effect.


Assuntos
Transportador 1 de Aminoácido Excitatório , Audição , Animais , Feminino , Masculino , Camundongos , Sistema X-AG de Transporte de Aminoácidos/genética , Sistema X-AG de Transporte de Aminoácidos/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Transportador 1 de Aminoácido Excitatório/genética , Audição/genética , Audição/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo
11.
Front Cell Dev Biol ; 9: 720902, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422838

RESUMO

High-intensity noise can cause permanent hearing loss; however, short-duration medium-intensity noise only induces a temporary threshold shift (TTS) and damages synapses formed by inner hair cells (IHCs) and spiral ganglion nerves. Synaptopathy is generally thought to be caused by glutamate excitotoxicity. In this study, we investigated the expression levels of vesicle transporter protein 3 (Vglut3), responsible for the release of glutamate; glutamate/aspartate transporter protein (GLAST), responsible for the uptake of glutamate; and Na+/K+-ATPase α1 coupled with GLAST, in the process of synaptopathy in the cochlea. The results of the auditory brainstem response (ABR) and CtBP2 immunofluorescence revealed that synaptopathy was induced on day 30 after 100 dB SPL noise exposure in C57BL/6J mice. We found that GLAST and Na+/K+-ATPase α1 were co-localized in the cochlea, mainly in the stria vascularis, spiral ligament, and spiral ganglion cells. Furthermore, Vglut3, GLAST, and Na+/K+-ATPase α1 expression were disrupted after noise exposure. These results indicate that disruption of glutamate release and uptake-related protein expression may exacerbate the occurrence of synaptopathy.

12.
J Occup Health ; 63(1): e12235, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34089209

RESUMO

OBJECTIVE: To evaluate the immunotoxicity and effects of noise and/or low-concentration carbon monoxide (CO) exposure on immune organs and immune functions in rats. METHODS: Male Wistar rats exposed to 98 dB(A) white noise and/or 100 ppm CO 4 h/d for 30 d were used to determine the pathological changes in the thymus and spleen, and variations in leukocyte counts, inflammatory factors, and immunoglobulin (Ig) concentrations. RESULTS: The boundaries of the cortex and medulla of the thymus were unclear following noise and combined exposure. The pathological changes in spleen after CO and combined exposure included blurred boundaries of red-pulp and white-pulp, disappearance of normal splenic nodules and neutrophil infiltration. After exposure to noise and in combination, leukocyte and lymphocyte counts decreased significantly. After exposure to low-concentration CO and in combination, serum IgM and IgG levels decreased significantly, but the levels of tumor necrosis factor-α and interferon-γ levels increased significantly. Eosinophils and IgA levels decreased significantly following exposure to noise and/or low concentration of CO, while the level of interleukin-1 increased significantly. Monocytes increased significantly only under noise or CO exposure, but not under combined exposure. CONCLUSIONS: Noise and/or low-concentration CO exposure may suppress innate and adaptive immune functions and induce inflammatory responses. Noise exposure mainly affected the innate immune function of rats, whereas low-concentration CO exposure mainly affected adaptive immune functions. Combined exposure presented higher immunotoxicity than noise or CO alone, suggesting that exposure to noise and low-concentration CO in the living and working environments can affect the immune system.


Assuntos
Monóxido de Carbono/toxicidade , Exposição Ambiental/efeitos adversos , Imunidade , Imunotoxinas/toxicidade , Ruído/efeitos adversos , Imunidade Adaptativa , Animais , Imunidade Inata , Imunoglobulinas/sangue , Mediadores da Inflamação/sangue , Contagem de Leucócitos , Masculino , Ratos , Ratos Wistar , Baço/patologia , Timo/patologia
13.
Curr Alzheimer Res ; 18(1): 14-24, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33761858

RESUMO

BACKGROUND: Environmental risk factors, including environmental noise stress, and genetic factors, have been associated with the occurrence and development of Alzheimer's disease (AD). However, the exact role and mechanism of AD-like pathology induced by environment-gene interactions between environmental noise and APP/PS1 gene remain elusive. METHODS: Herein, we investigated the impact of chronic noise exposure on AD-like neuropathology in APP/PS1 transgenic mice. The Morris water maze (MWM) task was conducted to evaluate AD-like changes. The hippocampal phosphorylated Tau, amyloid-ß (Aß), and neuroinflammation were assessed. We also assessed changes in positive feedback loop signaling of the voltage-dependent anion channel 1 (VDAC1) to explore the potential underlying mechanism linking AD-like neuropathology to noise-APP/PS1 interactions. RESULTS: Long-term noise exposure significantly increased the escape latency and the number of platform crossings in the MWM task. The Aß overproduction was induced in the hippocampus of APP/PS1 mice, along with the increase of Tau phosphorylation at Ser396 and Thr231 and the increase of the microglia and astrocytes markers expression. Moreover, the VDAC1-AKT (protein kinase B)-GSK3ß (glycogen synthase kinase 3 beta)-VDAC1 signaling pathway was abnormally activated in the hippocampus of APP/PS1 mice after noise exposure. CONCLUSION: Chronic noise exposure and APP/PS1 overexpression may synergistically exacerbate cognitive impairment and neuropathological changes that occur in AD. This interaction may be mediated by the positive feedback loop of the VDAC1-AKT-GSK3ß-VDAC1 signaling pathway.

14.
J Neuroinflammation ; 18(1): 9, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407614

RESUMO

BACKGROUND: Both genetic factors and environmental hazards, including environmental noise stress, have been associated with gut microbiome that exacerbates Alzheimer's disease (AD) pathology. However, the role and mechanism of environmental risk factors in early-onset AD (EOAD) pathogenesis remain unclear. METHODS: The molecular pathways underlying EOAD pathophysiology following environmental noise exposure were evaluated using C57BL/6 wild-type (WT) and APP/PS1 Tg mouse models. The composition differences in intestinal microbiota were analyzed by 16S rRNA sequencing and Tax4Fun to predict the metagenome content from sequencing results. An assessment of the flora dysbiosis-triggered dyshomeostasis of oxi-inflamm-barrier and the effects of the CNS end of the gut-brain axis was conducted to explore the underlying pathological mechanisms. RESULTS: Both WT and APP/PS1 mice showed a statistically significant relationship between environmental noise and the taxonomic composition of the corresponding gut microbiome. Bacterial-encoded functional categories in noise-exposed WT and APP/PS1 mice included phospholipid and galactose metabolism, oxidative stress, and cell senescence. These alterations corresponded with imbalanced intestinal oxidation and anti-oxidation systems and low-grade systemic inflammation following noise exposure. Mechanistically, axis-series experiments demonstrated that following noise exposure, intestinal and hippocampal tight junction protein levels reduced, whereas serum levels of inflammatory mediator were elevated. Regarding APP/PS1 overexpression, noise-induced abnormalities in the gut-brain axis may contribute to aggravation of neuropathology in the presymptomatic stage of EOAD mice model. CONCLUSION: Our results demonstrate that noise exposure has deleterious effects on the homeostasis of oxi-inflamm-barrier in the microbiome-gut-brain axis. Therefore, at least in a genetic context, chronic noise may aggravate the progression of EOAD.


Assuntos
Doença de Alzheimer/metabolismo , Exposição Ambiental/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Homeostase/fisiologia , Mediadores da Inflamação/metabolismo , Ruído/efeitos adversos , Estimulação Acústica/efeitos adversos , Doença de Alzheimer/etiologia , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
15.
Anal Chem ; 92(22): 15137-15144, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33119272

RESUMO

Pluripotency of a DNA tetrahedron (DNATT) has made the iconic framework a compelling keystone in biosensors and biodevices. Herein, distinct from the well-tapped applications in substrate fabrication, we focus on exploring their tracing and signaling potentials. A homologous family of four isostructural DNATT, i.e., DNATTα/ß/γ/δ, was engineered to form a sensor circuitry, in which a target-specific monolayer of thiolated DNATTγ pinned down the analyte jointly with the reciprocal DNATTδ into a sandwich complex; the latter further rallied an in situ interdigital relay of biotinylated DNATTα/ß into a microsized hyperlink dubbed polyDNATT. Its scale and growth factors were illuminated rudimentarily in transmission electron microscopy and confocal laser scanning microscopy. Using a nonsmall-cell lung cancer-related microRNA (hsa-miR-193a-3p) as the subject, a compound DNA-backboned construct was synthesized, fusing all building blocks together. Its superb tacticity and stereochemical conformality avail the templating of a horseradish peroxidase train, which boosted the paralleled catalytic surge of proton donors, resulting in an attomolar detection limit and a broad calibration range of more than seven orders of magnitude. Such oligomerization bested the conventional hybridization chain reaction laddering at both biomechanical stability and stoichiometric congruency. More significantly, it demonstrates the flexibility of DNA architectures and their multitasking ability in biosensing.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , MicroRNAs/análise , Linhagem Celular Tumoral , Eletroquímica , Humanos , Limite de Detecção , MicroRNAs/química , Nanoestruturas/química , Hibridização de Ácido Nucleico
16.
Anal Chem ; 92(20): 14076-14084, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32938180

RESUMO

Being announced as one of the "2019 Top Ten Emerging Technologies in Chemistry" by IUPAC, the directed evolution of artificial metalloenzymes has led to a broad scope of abiotic processes. Here, inspired by those key proteins in bioluminescence, a rudimentary expression of bio-electrochemiluminescent (ECL) macromolecules was achieved via the complexation of zinc proto-porphyrin IX (ZnPPIX) within apo-hemoglobin (apo-Hb). A high-yield monochromic irradiation at 644 nm could be provoked potentiostatically from the reconstituted holo-HbZnPPIX in solutions. Its secondary structure integrity was elucidated by UV and circular dichroism spectrometry, while voltammetry-hyphenated surface plasmon resonance authenticated its ligation conservativeness in electrical fields. Further conjugation with streptavidin rendered a homogeneous Janus fusion of both receptor and reporter domains, enabling a new abiological catalyst-linked ECL bioassay. On the other hand, singular ZnPPIX inside each tetrameric subunit of Hb accomplished an overall signal amplification without the bother of luminogenic heterojunctions. This pH-tolerant and non-photobleaching optics was essentialized to be the unique configuration interaction between Zn and O2, by which the direct electrochemistry of proteins catalyzed the transient progression of O2 → O2·- → O2* + hυ selectively. Such principle was implemented as a signal-on strategy for the determination of a characteristic cancer biomarker, the vascular endothelial growth factor, resulting in competent performance at a low detection limit of 0.6 pg·mL-1 and a wide calibration range along with good stability and reliability in real practices. This simple mutation repurposed the O2-transport Hb in the erythrocytes of almost all vertebrates into a cluster of oxidoreductases with intrinsic ECL activity, which would enrich the chromophore library. More importantly, its genetically engineered variants may come in handy in biomedical diagnosis and visual electrophysiology.


Assuntos
Hemoglobinas/química , Metaloporfirinas/química , Fator A de Crescimento do Endotélio Vascular/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletroquímica , Humanos , Concentração de Íons de Hidrogênio , Imunoensaio , Limite de Detecção , Medições Luminescentes , Oxigênio/química , Fotodegradação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estreptavidina/química , Ressonância de Plasmônio de Superfície
17.
BMC Genomics ; 21(1): 473, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650715

RESUMO

BACKGROUND: Previous studies found that cell-free DNA (cfDNA) generated from tumors was shorter than that from healthy cells, and selecting short cfDNA could enrich for tumor cfDNA and improve its usage in early cancer diagnosis and treatment monitoring; however, the underlying mechanism of shortened tumor cfDNA was still unknown, which potentially limits its further clinical application. RESULTS: Using targeted sequencing of cfDNA in a large cohort of solid tumor patient, sequencing reads harboring tumor-specific somatic mutations were isolated to examine the exact size distribution of tumor cfDNA. For the majority of studied cases, 166 bp remained as the peak size of tumor cfDNA, with tumor cfDNA showing an increased proportion of short fragments (100-150 bp). Less than 1% of cfDNA samples were found to be peaked at 134/144 bp and independent of tumor cfDNA purity. Using whole-genome sequencing of cfDNA, we discovered a positive correlation between cfDNA shortening and the magnitude of chromatin inaccessibility, as measured by transcription, DNase I hypersensitivity, and histone modifications. Tumor cfDNA shortening occurred simultaneously at both 5' and 3' ends of the DNA wrapped around nucleosomes. CONCLUSIONS: Tumor cfDNA shortening exhibited two distinctive modes. Tumor cfDNA purity and chromatin inaccessibility were contributing factors but insufficient to trigger a global transition from 166 bp dominant to 134/144 bp dominant phenotype.


Assuntos
Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Fragmentação do DNA , Neoplasias/diagnóstico , Montagem e Desmontagem da Cromatina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias/genética , Nucleossomos/química , Nucleossomos/genética , Sequenciamento Completo do Genoma
18.
Micromachines (Basel) ; 11(5)2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32443658

RESUMO

In this study, CoFe2O4 is selected for the first time to synthesize CoFe2O4/Al nanothermite films via an integration of nano-Al with CoFe2O4 nanowires (NWs), which can be prepared through a facile hydrothermal-annealing route. The resulting nanothermite film demonstrates a homogeneous structure and an intense contact between the Al and CoFe2O4 NWs at the nanoscale. In addition, both thermal analysis and laser ignition test reveal the superb energetic performances of the prepared CoFe2O4/Al NWs nanothermite film. Within different thicknesses of nano-Al for the CoFe2O4/Al NWs nanothermite films investigated here, the maximum heat output has reached as great as 2100 J·g-1 at the optimal thickness of 400 nm for deposited Al. Moreover, the fabrication strategy for CoFe2O4/Al NWs is also easy and suitable for diverse thermite systems based upon other composite metal oxides, such as MnCo2O4 and NiCo2O4. Importantly, this method has the featured advantages of simple operation and compatibility with microsystems, both of which may further facilitate potential applications for functional energetic chips.

19.
Biosens Bioelectron ; 150: 111963, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929091

RESUMO

In this work, pyrrolidyl C60 derivative was recruited as an unadulterated and congruent nano-hub to converge three zinc porphyrins on its monopole. Such peculiar assembly was convinced via micro-imaging and spectrophotometry. Making the best of fullerenyl proficiency in catalytic singlet O2 generation and excited-state preservation, a multiplied electrochemiluminescence (ECL) emission bursted out from the porphyrin trinity in a synergistic manner. Without any prebio-conjugation, this orderly ECL-active individual turned to anchor in the toroid of a peripherally modified gamma-cyclodextrin in a good shape match. From the facile direct mounting of the latter derives a universal bio-probing technique based upon such host-guest inclusion. Its binding pattern and the concomitant effects on interfacial properties were revealed by systematic process characterizations. Taking advantages of this uniform ensemble in both size and stoichiometry, an in situ terminal labelling strategy during the recognition-induced allosteric event came into being, which managed a neat signal enhancement for the detection of model miRNA marker. Even in real samples, the developed sensing approach could achieve high precision, comparable sensitivity and satisfactory selectivity. The adaptation of macrocyclic chemistry for refined biotransducers and efficient ECL amplifiers would offer a generic and potent alternative to the analyte-specified ECL indicator-receptor build in bioassays.


Assuntos
Técnicas Biossensoriais/métodos , Fulerenos/química , Metaloporfirinas/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Humanos , Medições Luminescentes/métodos , MicroRNAs/sangue , Modelos Moleculares , gama-Ciclodextrinas/química
20.
Environ Health Prev Med ; 25(1): 3, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31918655

RESUMO

BACKGROUND: Chronic noise exposure is one environmental hazard that is associated with genetic susceptibility factors that increase Alzheimer's disease (AD) pathogenesis. However, the comprehensive understanding of the link between chronic noise stress and AD is limited. Herein, we investigated the effects of chronic noise exposure on AD-like changes in senescence-accelerated mouse prone 8 (SAMP8). METHODS: A total of 30 male SAMP8 mice were randomly divided into the noise-exposed group, the control group, and aging group (positive controls), and mice in the exposure group were exposed to 98 dB SPL white noise for 30 consecutive days. Transcriptome analysis and AD-like neuropathology of hippocampus were examined by RNA sequencing and immunoblotting. Enzyme-linked immunosorbent assay and real-time PCR were used to further determine the differential gene expression and explore the underlying mechanisms of chronic noise exposure in relation to AD at the genome level. RESULTS: Chronic noise exposure led to amyloid beta accumulation and increased the hyperphosphorylation of tau at the Ser202 and Ser404 sites in young SAMP8 mice; similar observations were noted in aging SAMP8 mice. We identified 21 protein-coding transcripts that were differentially expressed: 6 were downregulated and 15 were upregulated after chronic noise exposure; 8 genes were related to AD. qPCR results indicated that the expression of Arc, Egr1, Egr2, Fos, Nauk1, and Per2 were significantly high in the noise exposure group. These outcomes mirrored the results of the RNA sequencing data. CONCLUSIONS: These findings further revealed that chronic noise exposure exacerbated aging-like impairment in the hippocampus of the SAMP8 mice and that the protein-coding transcripts discovered in the study may be key candidate regulators involved in environment-gene interactions.


Assuntos
Doença de Alzheimer/patologia , Hipocampo/metabolismo , Ruído/efeitos adversos , Transcriptoma , Doença de Alzheimer/metabolismo , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Masculino , Ratos
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