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1.
Aging (Albany NY) ; 16(5): 4348-4362, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38431308

RESUMO

Diesel exhaust particles (DEPs) are major air pollutants emitted from automobile engines. Prenatal exposure to DEPs has been linked to neurodevelopmental and neurodegenerative diseases associated with aging. However, the specific mechanism by DEPs impair the hippocampal synaptic plasticity in the offspring remains unclear. Pregnant C57BL/6 mice were administered DEPs solution via the tail vein every other day for a total of 10 injections, then the male offsprings were studied to assess learning and memory by the Morris water maze. Additionally, protein expression in the hippocampus, including CPEB3, NMDAR (NR1, NR2A, NR2B), PKA, SYP, PSD95, and p-CREB was analyzed using Western blotting and immunohistochemistry. The alterations in the histomorphology of the hippocampus were observed in male offspring on postnatal day 7 following prenatal exposure to DEPs. Furthermore, 8-week-old male offspring exposed to DEPs during prenatal development exhibited impairments in the Morris water maze test, indicating deficits in learning and memory. Mechanistically, the findings from our study indicate that exposure to DEPs during pregnancy may alter the expression of CPEB3, SYP, PSD95, NMDAR (NR1, NR2A, and NR2B), PKA, and p-CREB in the hippocampus of both immature and mature male offspring. The results offer evidence for the role of the NMDAR/PKA/CREB and CPEB3 signaling pathway in mediating the learning and memory toxicity of DEPs in male offspring mice. The alterations in signaling pathways may contribute to the observed damage to synaptic structure and transmission function plasticity caused by DEPs. The findings hold potential for informing future safety assessments of DEPs.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Emissões de Veículos , Feminino , Gravidez , Humanos , Camundongos , Animais , Masculino , Emissões de Veículos/toxicidade , Aprendizagem em Labirinto , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Camundongos Endogâmicos C57BL , Receptores de N-Metil-D-Aspartato/metabolismo , Hipocampo/metabolismo , Plasticidade Neuronal , Proteínas de Ligação a RNA/metabolismo
2.
ACS Sens ; 8(10): 3973-3984, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37725347

RESUMO

Distinguishing between heavy water and regular water has been a continuing challenge since these isotopologues of water have very similar physical and chemical properties. We report the development and evaluation of a simple, inexpensive sensor capable of detecting liquid D2O and other isotopologues of liquid water through the measurement of electrical signals generated from a nanoporous alumina film. This electrical output, consisting of a sharp voltage pulse followed by a separate broad voltage pulse, is present during the application of microliter volumes of liquid. The amplitude and temporal characteristics of these pulses have been combined to enable four diagnostic parameters for sensing D2O and H218O. The sensing mechanism is based on different modification effects on the alumina surface by H2O and D2O, spatially localized variations in the surface potential of alumina induced by isotopically substituted water molecules, combined with the effect of isotopic composition on charge transfer. As a proof-of-concept demonstration, a sensing system has been developed that provides real-time detection of liquid D2O in a stand-alone system.


Assuntos
Óxido de Alumínio , Água , Água/química , Óxido de Deutério
3.
Math Biosci Eng ; 20(7): 13061-13085, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37501478

RESUMO

PURPOSE: Coronary microvascular dysfunction (CMD) is emerging as an important cause of myocardial ischemia, but there is a lack of a non-invasive method for reliable early detection of CMD. AIM: To develop an electrocardiogram (ECG)-based machine learning algorithm for CMD detection that will lay the groundwork for patient-specific non-invasive early detection of CMD. METHODS: Vectorcardiography (VCG) was calculated from each 10-second ECG of CMD patients and healthy controls. Sample entropy (SampEn), approximate entropy (ApEn), and complexity index (CI) derived from multiscale entropy were extracted from ST-T segments of each lead in ECGs and VCGs. The most effective entropy subset was determined using the sequential backward selection algorithm under the intra-patient and inter-patient schemes, separately. Then, the corresponding optimal model was selected from eight machine learning models for each entropy feature based on five-fold cross-validations. Finally, the classification performance of SampEn-based, ApEn-based, and CI-based models was comprehensively evaluated and tested on a testing dataset to investigate the best one under each scheme. RESULTS: ApEn-based SVM model was validated as the optimal one under the intra-patient scheme, with all testing evaluation metrics over 0.8. Similarly, ApEn-based SVM model was selected as the best one under the intra-patient scheme, with major evaluation metrics over 0.8. CONCLUSIONS: Entropies derived from ECGs and VCGs can effectively detect CMD under both intra-patient and inter-patient schemes. Our proposed models may provide the possibility of an ECG-based tool for non-invasive detection of CMD.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Humanos , Entropia , Eletrocardiografia/métodos , Algoritmos , Isquemia Miocárdica/diagnóstico
4.
Front Physiol ; 13: 854191, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707012

RESUMO

Background: Myocardial ischemia is a common early symptom of cardiovascular disease (CVD). Reliable detection of myocardial ischemia using computer-aided analysis of electrocardiograms (ECG) provides an important reference for early diagnosis of CVD. The vectorcardiogram (VCG) could improve the performance of ECG-based myocardial ischemia detection by affording temporal-spatial characteristics related to myocardial ischemia and capturing subtle changes in ST-T segment in continuous cardiac cycles. We aim to investigate if the combination of ECG and VCG could improve the performance of machine learning algorithms in automatic myocardial ischemia detection. Methods: The ST-T segments of 20-second, 12-lead ECGs, and VCGs were extracted from 377 patients with myocardial ischemia and 52 healthy controls. Then, sample entropy (SampEn, of 12 ECG leads and of three VCG leads), spatial heterogeneity index (SHI, of VCG) and temporal heterogeneity index (THI, of VCG) are calculated. Using a grid search, four SampEn and two features are selected as input signal features for ECG-only and VCG-only models based on support vector machine (SVM), respectively. Similarly, three features (S I , THI, and SHI, where S I is the SampEn of lead I) are further selected for the ECG + VCG model. 5-fold cross validation was used to assess the performance of ECG-only, VCG-only, and ECG + VCG models. To fully evaluate the algorithmic generalization ability, the model with the best performance was selected and tested on a third independent dataset of 148 patients with myocardial ischemia and 52 healthy controls. Results: The ECG + VCG model with three features (S I ,THI, and SHI) yields better classifying results than ECG-only and VCG-only models with the average accuracy of 0.903, sensitivity of 0.903, specificity of 0.905, F1 score of 0.942, and AUC of 0.904, which shows better performance with fewer features compared with existing works. On the third independent dataset, the testing showed an AUC of 0.814. Conclusion: The SVM algorithm based on the ECG + VCG model could reliably detect myocardial ischemia, providing a potential tool to assist cardiologists in the early diagnosis of CVD in routine screening during primary care services.

5.
Artigo em Inglês | MEDLINE | ID: mdl-35670465

RESUMO

Artificial ion channels with tunable ionic transport control and intelligent iontronic functions at the nanoscale have a wide application in logic computing and biosensing. Although some artificial ion channels with smart ion transport characteristics have been developed, most of them are constructed on porous membranes with undefined channel numbers. It is still challenging to achieve multiple ion transport features in single nanochannels and to control the ion flow more accurately with excellent repeatability. In this paper, a design strategy is presented to fabricate pH-responsive ion channels with various ion transport features based on a single polydimethylsiloxane (PDMS) nanochannel. The single-ion nanochannel developed by this approach can be further integrated into electronic systems on a chip. Three types of artificial ion channels are demonstrated and investigated systematically in this work. With symmetric or asymmetric pH stimuli, these ion channels can alternatively change their working states among an opened state, a closed state, and an ionic diode state. Four different ion transport features can be realized in a triple-gated ion channel system. With these advantages of the design, it is promising to build smart nanofluidic iontronic devices with widespread applicability in energy conversions, active ion transport control, and biological analysis.

6.
Nanoscale Horiz ; 7(3): 299-310, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35064257

RESUMO

The memristor is a promising candidate to implement high-density memory and neuromorphic computing. Based on the characteristic retention time, memristors are classified into volatile and non-volatile types. However, a single memristor generally provides a specific function based on electronic performances, which poses roadblocks for further developing novel circuits. Versatile memristors exhibiting both volatile and non-volatile properties can provide multiple functions covering non-volatile memory and neuromorphic computing. In this work, a versatile memristor with volatile/non-volatile bifunctional properties was developed. Non-volatile functionality with a storage window of 4.0 × 105 was obtained. Meanwhile, the device can provide threshold volatile functionalities with a storage window of 7.0 × 104 and a rectification ratio of 4.0 × 104. The leaky integrate-and-fire (LIF) neuron model and artificial synapse based on the device have been studied. Such a versatile memristor enables non-volatile memory, selectors, artificial neurons, and artificial synapses, which will provide advantages regarding circuit simplification, fabrication processes, and manufacturing costs.


Assuntos
Redes Neurais de Computação , Sinapses , Custos e Análise de Custo , Eletrônica , Neurônios/fisiologia
7.
Pharmacol Res ; 171: 105767, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34273490

RESUMO

Recent studies show that the nutraceutical supplement dihydromyricetin (DHM) can alleviate IBD in murine models by downregulating the inflammatory pathways. However, the molecular mechanistic link between the therapeutic efficiency of DHM, gut microbiota, and the metabolism of microbial BAs remains elusive. In this study, we explored the improvement of DHM on the dysregulated gut microbiota of mice with dextran sulfate sodium (DSS)-induced colitis. We found that DHM could markedly improve colitis symptoms, gut barrier disruption, and colonic inflammation in DSS-treated mice. In addition, bacterial 16S rDNA sequencing assay demonstrated that DHM could alleviate gut dysbiosis in mice with colitis. Furthermore, antibiotic-mediated depletion of the gut microflora and fecal microbiome transplantation (FMT) demonstrated that the therapeutic efficiency of DHM was closely associated with gut microbiota. BA-targeted metabolomics analysis revealed that DHM restored the metabolism of microbial BAs in the gastrointestinal tract during the development of colitis. DHM significantly enriched the proportion of the beneficial Lactobacillus and Akkermansia genera, which were correlated with increased gastrointestinal levels of unconjugated BAs involving chenodeoxycholic acid and lithocholic acid, enabling the BAs to activate specific receptors, such as FXR and TGR5, and maintaining intestinal integrity. Taken together, DHM could alleviate DSS-induced colitis in mice by restoring the dysregulated gut microbiota and BA metabolism, leading to improvements in intestinal barrier function and colonic inflammation. Increased microbiota-BAs-FXR/TGR5 signaling may be the potential targets of DHM in colitis. Therefore, our findings provide novel insights into the development of novel DHM-derived drugs for the management of IBD.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/terapia , Disbiose/terapia , Flavonóis/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Bactérias/genética , Bactérias/metabolismo , Ácidos e Sais Biliares/metabolismo , Células CACO-2 , Colite/induzido quimicamente , Colite/imunologia , Colite/microbiologia , Colo/imunologia , Colo/patologia , Sulfato de Dextrana , Disbiose/induzido quimicamente , Disbiose/imunologia , Disbiose/microbiologia , Transplante de Microbiota Fecal , Fezes/microbiologia , Flavonóis/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Interleucina-1beta/imunologia , Masculino , Camundongos Endogâmicos C57BL , Receptores Citoplasmáticos e Nucleares/imunologia , Receptores Acoplados a Proteínas G/imunologia , Fator de Necrose Tumoral alfa/imunologia
8.
ACS Appl Mater Interfaces ; 13(29): 34266-34273, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34255972

RESUMO

We report the development of low-cost triboelectric nanogenerators (TENGs) based on polypropylene (PP) fabrics formulated via an inexpensive melt-blowing process with an output voltage as high as 50 V. By disinfection methods such as exposure to steam, ethanol, and dry heat at 75 °C, the commercial medical masks and N95 filtering facepiece respirators (FFRs) can be reused to fabricate PP fiber based TENGs, which provide a novel regime for energy-harvesting devices based on reusable materials. As a power source, the output of one TENG can drive 15 serially connected light-emitting diodes (LEDs) or a commercial electric calculator. PP fabric TENGs can also work as self-powered sensors for the high-sensitivity detection of mechanical impact. We provide examples where the TENG is used to detect biomechanical motion such as that associated with the extension of an elbow, the touch of a finger, the impact of footsteps, and the bending of a knee without an external power supply. Most importantly, these PP fabrics for TENGs can be obtained from decontaminated medical masks that are generated as tremendous wastes every day, which provide a great potential as sustainable energy. These properties suggest that PP fabric based TENGs are promising for harvesting energy from biological systems and that they may facilitate the large-scale production of a new range of inexpensive self-powered multifunctional wearable sensors for applications in healthcare, security, and information networks.

9.
ACS Appl Mater Interfaces ; 13(23): 27169-27178, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34081434

RESUMO

Harvesting energy from ambient moisture and natural water sources is currently of great interest due to the need for standalone self-powered nano/micro-systems. In this work, we report on the development of a cost-effective nanogenerator based on a carbon paper-Al2O3 nanoparticle layer-carbon paper (CAC) sandwich structure, where the 3D Al2O3 layer is deposited via vacuum filtration. This type of device can produce an open-circuit voltage (UOC) of up to 4 V and a short-circuit current (ISC) of ∼18 µA with only an 8 µL water droplet applied. To our knowledge, this is the highest voltage yet reported from a single moisture/water-induced electricity nanogenerator using solid oxides and carbon-based materials. A remarkable output power of 14.8 µW can be reached with an optimized resistive load. An LED with a working voltage of 3-3.2 V can operate for a short time with the power from a single CAC device exposed to one 8 µL water droplet. Furthermore, a CAC generator adsorbing as little as 2 µL water droplets every 3 min can also give a UOC of 3.63 V. We show that CAC devices provide a robust electrical output over more than 200 wet-dry cycles without any deterioration in performance. These units demonstrate much promise as cost-effective electricity generators for harvesting energy from natural sources like rainwater, tap water, snow runoff, and dew. The response time of CAC devices can be as fast as 10-100 ms, making them ideal for applications as self-powered water detectors. The generation of power in this device arises from the streaming current. To assist in the optimization of these devices, we have analyzed how their response is related to such factors as layer thickness, time interval between application of water droplets, and the volume of each water droplet.

10.
Front Physiol ; 12: 660232, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868027

RESUMO

In recent years, coronary heart disease (CHD) has become one of the main diseases that endanger human health, with a high mortality and disability rate. Myocardial ischemia (MI) is the main symptom in the development of CHD. Continuous and severe myocardial ischemia will lead to myocardial infarction. The clinical manifestations of MI are mainly the changes of ST-T segment of ECG, that is, ST segment and T wave. Nearly one third of patients with CHD, however, has no obvious ECG changes. In this paper, a new method for detecting MI based on the T-wave area curve (TWAC) was proposed. Through observation and analysis of clinical data, it was found that there exist significant correlation between the morphology of TWAC and MI. The TWAC morphology of normal subject is smooth and gentle, while the TWAC morphology of patients with coronary stenosis is mostly jagged, and the curve becomes more severe with more severe stenosis. The preliminary test results show that the sensitivity, specificity, and accuracy of the proposed method for detecting MI are 84.3, 83.6, and 84%, respectively. This study shows that the TWAC based approach may be an effective method for detecting MI, especially for the CHD patients with no obvious ECG changes.

11.
Adv Mater ; 33(16): e2008395, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33734513

RESUMO

The intermolecular H-bonding density heavily influences the gelation and rheological behavior of hydrogen-bonded supramolecular polymer hydrogels, thus offering a delicate pathway to tailor their physicochemical properties for meeting a specific biomedical application. Herein, one methylene spacer between two amides in the side chain of N-acryloyl glycinamide (NAGA) is introduced to generate a variant monomer, N-acryloyl alaninamide (NAAA). Polymerization of NAAA in aqueous solution affords an unprecedented ultrasoft and highly swollen supramolecular polymer hydrogel due to weakened H-bonds caused by an extra methylene spacer, which is verified by variable-temperature Fourier transform infrared (FTIR) spectroscopy and simulation calculation. Intriguingly, poly(N-acryloyl alaninamide) (PNAAA) hydrogel can be tuned to form a transient network with a self-fused and excellent antifouling capability that results from the weakened dual amide H-bonding interactions and enhanced water-amide H-bonding interactions. This self-fused PNAAA hydrogel can completely inhibit postoperative abdominal adhesion and recurrent adhesion after adhesiolysis in vivo. This transient hydrogel network allows for its disintegration and excretion from the body. The molecular mechanism studies reveal the signal pathway of PNAAA hydrogel in inhibiting inflammatory response and regulating fibrinolytic system balance. This self-fused, antifouling ultrasoft supramolecular hydrogel is promising as a barrier biomaterial for completely preventing postoperative tissue adhesion.


Assuntos
Materiais Biocompatíveis , Hidrogéis , Aderências Teciduais , Ligação de Hidrogênio , Polimerização , Reologia , Temperatura , Água/química
12.
Biomater Sci ; 8(6): 1702-1710, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-31994544

RESUMO

Traditional hydrogel dressings are limited in practical applications due to the complexity of the preparation and low biocompatibility. So, there is an urgent need to design wound dressing with simple preparation method, higher biocompatibility, and superior therapeutic effect. Additionally, using a polysaccharide/protein mixture system is an attractive method to prepare the gel. In this study, a simple mixture of hyaluronic acid/lysozyme (HL) was used to obtain the HL coacervate gel. HL coacervate has suitable viscoelasticity and excellent adhesion on the skin tissue. We demonstrated its highly efficient self-healing property to overcome fracture or deformation. HL coacervate showed a significant effect on promoting wound healing in a full-thickness skin defect model. Compared to the commercial 3M dressing, it has faster epithelial tissue regeneration and stronger collagen deposition. In addition, cytotoxicity and organ toxicity tests indicated its high safety. In summary, HL coacervate has broad clinical application prospects as a wound dressing material.


Assuntos
Ácido Hialurônico/farmacologia , Muramidase/farmacologia , Pele/lesões , Cicatrização/efeitos dos fármacos , Adesividade , Animais , Curativos Hidrocoloides , Ácido Hialurônico/química , Camundongos , Modelos Biológicos , Muramidase/química , Pele/efeitos dos fármacos , Suínos
13.
Comput Math Methods Med ; 2019: 8237071, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827590

RESUMO

Impaired sarcoplasmic reticulum (SR) calcium transport ATPase (SERCA) gives rise to Ca2+ alternans and changes of the Ca2+release amount. These changes in Ca2+ release amount can reveal the mechanism underlying how the interaction between Ca2+ release and Ca2+ uptake induces Ca2+ alternans. This study of alternans by calculating the values of Ca2+ release properties with impaired SERCA has not been explored before. Here, we induced Ca2+ alternans by using an impaired SERCA pump under ischemic conditions. The results showed that the recruitment and refractoriness of the Ca2+ release increased as Ca2+ alternans occurred. This indicates triggering Ca waves. As the propagation of Ca waves is linked to the occurrence of Ca2+ alternans, the "threshold" for Ca waves reflects the key factor in Ca2+ alternans development, and it is still controversial nowadays. We proposed the ratio between the diastolic network SR (NSR) Ca content (Cansr) and the cytoplasmic Ca content (Ca i ) (Cansr/Ca i ) as the "threshold" of Ca waves and Ca2+ alternans. Diastolic Cansr, Ca i , and their ratio were recorded at the onset of Ca2+ alternans. Compared with certain Cansr and Ca i , the "threshold" of the ratio can better explain the comprehensive effects of the Ca2+ release and the Ca2+ uptake on Ca2+ alternans onset. In addition, these ratios are related with the function of SERCA pumps, which vary with different ischemic conditions. Thus, values of these ratios could be used to differentiate Ca2+ alternans from different ischemic cases. This agrees with some experimental results. Therefore, the certain value of diastolic Cansr/Ca i can be the better "threshold" for Ca waves and Ca2+ alternans.


Assuntos
Sinalização do Cálcio , Isquemia Miocárdica/fisiopatologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Retículo Sarcoplasmático/enzimologia , Potenciais de Ação , Animais , Arritmias Cardíacas/fisiopatologia , Cálcio/metabolismo , Citoplasma/metabolismo , Diástole , Humanos , Concentração de Íons de Hidrogênio , Modelos Cardiovasculares , Isquemia Miocárdica/enzimologia , Pericárdio/metabolismo , Fosforilação , Coelhos , Termodinâmica
14.
Clin Lab ; 65(11)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31710435

RESUMO

BACKGROUND: Complex chromosome rearrangement (CCR) often results in patients with mental retardation, stunted growth, and multiple abnormalities. CCR carriers are at high risk of adverse pregnancy, and prenatal diagnosis should be made even in normal pregnancy. The incidence of spermatogenesis disorder is high in male CCR carriers, and the chromosome involved with CCR has an impact on the fertility of male carriers. METHODS: We report a case of complex chromosome translocation: 46, XY, t(4; 10; 13) (q31; q23; q12). The lymphocytes in peripheral blood were cultured to examine the patient's karyotype. RESULTS: The patient's karyotype was detected and identified as 46, XY, t(4;10;13) (4pter→4q31::13q12→13qter; 10pter→10q23::4q31→4qter; 13pter→13q12::10q23→10qter). Complex chromosome translocations occurred on chromosomes 4, 10, and 13. When combined with normal gamete, one or two derived chromosomes may be obtained in the offspring, resulting in the increase or decrease of the translocation segments of a chromosome (part of trisomy or part of monomers), thus resulting in fetal abortion, stillbirth or deformed children, etc. Conclusions: Fertility and pregnancy outcome cannot be completely determined according to the complexity of karyotype. For patients with such chromosomal abnormalities, prenatal diagnosis should be strictly carried out to prevent the birth of children with chromosomal diseases if they want to have healthy children.


Assuntos
Aborto Espontâneo/genética , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 4 , Transtorno 46,XY do Desenvolvimento Sexual/genética , Fertilidade/genética , Infertilidade Masculina/genética , Translocação Genética , Aborto Espontâneo/fisiopatologia , Adulto , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Transtorno 46,XY do Desenvolvimento Sexual/fisiopatologia , Feminino , Predisposição Genética para Doença , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/fisiopatologia , Cariótipo , Masculino , Fenótipo , Gravidez
15.
J Biomed Nanotechnol ; 15(3): 417-430, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31165689

RESUMO

In this study, a cell-penetrating peptide named Acylated Steric acid-9 poly-arginine (r9-SA) was sucessfully synthesized. High performance liquid chromatography (HPLC) and mass spectrometry (MS) were used to characterize the structural formula of r9-SA. Diclofenac sodium was chosen as a model drug, and the transdermal permeation-enhancing effect of r9-SA was estimated in vitro. Skin irritation experiment and histopathological observation of tissue sections with HE and Masson staining were performed to analyze the security of r9-SA. The possible penetration-enhancing mechanism of r9-SA was characterized with laser scanning confocal microscopy (LSCM), differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and laser Raman spectroscopy, respectively. The in vitro penetration study showed that r9-SA has a promoting effect for enhancing the transdermal penetration of diclofenac sodium. Skin irritation experiment and histopathological observation results showed that r9-SA has good biocompatibility with skin. The experiments were carried on to characterize the penetration mechanism of r9 -SA. It was found that r9-SA may react with the keratin in the stratum corneum (SC), changing its secondary structure and so that drugs can penetrate through SC. In conclusion, all data showed that the r9-SA could be a safe and effective penetration enhancer for topical delivery of drug.


Assuntos
Peptídeos Penetradores de Células/administração & dosagem , Administração Cutânea , Arginina , Pele , Absorção Cutânea , Espectroscopia de Infravermelho com Transformada de Fourier
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