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1.
Plast Reconstr Surg ; 144(4): 897-905, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31568300

RESUMEN

BACKGROUND: Health care reforms aimed at bundling payments attempt to contain costs. Uncovering variation in spending provides one strategy for decreasing expenditure. This study aims to investigate interhospital cost variation for thumb replantation. METHODS: A retrospective cross-sectional analysis of patients undergoing thumb replantation using data from the Healthcare Cost and Utilization Project National Inpatient Sample database from 2001 to 2011 was performed. Univariate and multivariable logistic regression models were used to investigate associations between patient-level and hospital-level characteristics and cost. RESULTS: A total of 778 patients were included in the study, with a mean cost for thumb replantation of $20,965. Thumb replantations performed at high-volume hospitals were significantly more expensive than those performed at low-volume hospitals (median cost, $20,395 versus $13,463; p < 0.001), with longer lengths of stay (5 days versus 4 days), despite having similar surgical complication rates (p = 0.07). Thumb replantations performed in the West were significantly more expensive than those performed in the South (median cost, $22,579 in the West versus $14,823 in the South; p < 0.001), with longer lengths of stay (5 days versus 4 days; p = 0.005) and similar surgical complications (p = 0.239). In multivariable logistic regression, hospital volume (p < 0.001), hospital region (p < 0.001), and increased length of stay (p < 0.001) were predictive of higher cost. CONCLUSIONS: High-volume hospitals and hospitals in the West are more expensive, with longer lengths of stay, despite having similar complications. Expedited discharge may be one avenue for decreasing expenditure without compromising care.

2.
Oncol Rep ; 2019 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-31545455

RESUMEN

Poly(ADP­ribose) polymerase (PARP) inhibitors have little effect on homologous recombination repair (HRR)­proficient tumor types, such as cervical cancer. In addition to catalytic activity, the PARP inhibitor, BMN673, traps PARP1 on damaged DNA and induces cytotoxic effects. The aim of the present study was to evaluate the therapeutic effect of PI3K inhibitors and BMN673 on cervical cancer cells. The Chou­Talalay method was used to assess the synergistic effect of drug combinations on cervical cancer cells. The effect of PI3K inhibitors and BMN673 on cell growth and survival were also assessed via a Cell Counting Kit­8 assay and three­dimensional sphere culture. Cell migration and invasion were assessed via Transwell migration and Matrigel invasion assays, respectively. In addition, DNA damage and HRR competency were assessed via immunofluorescent staining analysis of γH2AX and RAD51 foci, and tail moment in a comet assay. PARP1 binding in chromatin was assessed via a cellular trapping assay. Ex vivo cultured sections of patient­derived cervical tumors were subjected to drug exposure followed by histological and immunohistochemical analyses. The results revealed that the PI3K p110α inhibitor BYL719 and the PARP inhibitor BMN673 synergized to inhibit cervical cancer cell proliferation, migration and invasion in vitro and ex vivo. However, the pan­PI3K inhibitor BKM120 did not produce the aforementioned effects. Additionally, cervical cancer cells exhibiting aberrant PI3K activation were more responsive to the combined inhibition of PI3K p110α and PARP. Mechanistically, BYL719 co­operated with BMN673 to increase PARP1 trapping on chromatin, induce severe DNA damage and exert cytotoxic effects. The combined use of BMN673 and BYL719 may serve as a promising therapeutic strategy for patients with cervical cancer exhibiting aberrant PI3K activation.

3.
Hepatology ; 2019 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-31556127

RESUMEN

We read with great interest the article of Siddiqui et al.(1) in HEPATOLOGY, which demonstrated that serum concentration of small dense low-density lipoprotein cholesterol (sdLDL-C) independently predicted CVD events. Indeed, this study provide a potential useful clinical tool in stratifying patients at risk for CVD events after liver transplantation (LT). We would, however, like to raise the following concerns.

4.
Zhen Ci Yan Jiu ; 44(9): 649-52, 2019.
Artículo en Chino | MEDLINE | ID: mdl-31532133

RESUMEN

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Baihui" (GV20) and "Zusanli" (ST36) on the expression of stromal cell derived factor-1α (SDF-1α) and CD34 in ischemic cortex tissue of cerebral ische-mia /reperfusion injury (CI/RI) rats, so as to study its mechanisms underlying improving CI/RI. METHODS: Thirty male SD rats were equally and randomly divided into sham operation, model and EA groups (n=10 rats in each group). The CI/RI model was established by occlusion of the middle cerebral artery for 120 min, followed by reperfusion. EA (40 Hz, 1-2 mA) was applied to GV20 and left ST36 for 20 min, once daily for successive 14 days. The neurological deficit severity was assessed by using Longa's and colleagues' methods. The histopathological changes of the ischemic tissues were observed after H.E. staining and the expression of SDF-1α and CD34 in the ischemic cortex tissues was detected by immunohistochemistry. RESULTS: After modeling, the neurological deficit score, and the numbers of SDF-1α and CD34-positive cells in the ischemic cerebral cortex tissue were significantly increased in the model group (P<0.05). Following EA intervention, the increased neurological deficit score was reversed at the 3rd, 7th and 14th day, and the increased SDF-1α and CD34-positive cells were significantly further up-regulated in the EA group (P<0.05). H.E. staining showed tissue edema, widening of the intercellular space, cavitation-like changes, neuronal shrinkage, nuclear pyknosis with hyperchroma or even disappearance, and aggregation of inflammatory and neurogliocytes in the model group. These situations were relatively milder in the EA group. CONCLUSION: EA of GV20 and ST36 can improve neurological function of CI/RI rats, which may be associated with its effect in up-regulating the expression of SDF-1α and CD34 proteins in the ischemic cerebral cortex tissues.


Asunto(s)
Isquemia Encefálica , Electroacupuntura , Daño por Reperfusión , Animales , Quimiocina CXCL12 , Masculino , Ratas , Ratas Sprague-Dawley , Células del Estroma
5.
J Neurophysiol ; 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31533006

RESUMEN

Previously, symmetry of network models has been proposed to account for interocular grouping during binocular rivalry. Here, we construct and analyze generalized rivalry network models with different types of symmetry (based on different kinds of excitatory coupling) to derive predictions of possible perceptual states in 12 experiments with four retinal locations. Percepts in binocular rivalry involving more than three locations have not been empirically investigated due to the difficulty in reporting simultaneous percepts at multiple locations. Here, we develop a novel reporting procedure in which the stimulus disappears when the subject is cued to report the simultaneously perceived colors in all four retinal locations. This procedure ensures that simultaneous rather than sequential percepts are reported. The procedure was applied in 12 experiments with six binocular rivalry stimulus configurations, all consisting of dichoptic displays of red and green squares at four locations. We call configurations with an even (resp.~odd) number of red squares even(resp. odd) configurations. In experiments using even stimulus configurations, we found that even percepts were more frequently observed than odd percepts, whereas in experiments using odd stimulus configurations even and odd percepts were observed with equal probability. The generalized rivalry network models in which couplings depend on stimulus features and spatial configurations was in better agreement with the empirical results. We conclude that the excitatory coupling strength in the horizontal and vertical configurations are different, and the coupling strengths between the same color and between different colors are different.

6.
Adv Mater ; 31(39): e1902793, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31414526

RESUMEN

A liquid-solid contact triboelectric nanogenerator (TENG) based on poly(tetrafluoroethylene) (PTFE) film, a copper electrode, and a glass substrate for harvesting energy in oil/water multiphases is reported. There are two distinctive signals being generated, one is from the contact electrification and electrostatic induction between the liquid (water/oil) and the PTFE film (VTENG and ITENG ); and the other is from the electrostatic induction in the copper electrode by the oil/water interfacial charges (ΔVinterface and Iinterface ), which is generated only when the liquid-solid contact TENG is inserted across the oil/water interface. The two signals show interesting opposite changing trends that the VTENG and ITENG decrease while the oil/water interfacial signals of ΔVinterface and Iinterface increase after coating a layer of polydopamine on the surfaces of PTFE and glass via self-polymerization. As an application of the observed phenomena, both the values of ITENG and Iinterface have a good linear relationship versus the natural logarithm of the concentration of the dopamine. Based on this, the first self-powered dual-signal detection of dopamine using TENG is demonstrated.

7.
J Am Chem Soc ; 141(36): 14239-14248, 2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31381306

RESUMEN

Multilevel protein structures typically involve polypeptides of sufficient lengths. Here we report the folding and assembly of seven short tetrapeptides sharing the same types of α-, ß-, and aromatic γ-amino acid residues. These are two sets of hybrid peptides, with three members in one set and four in the other, having complementary hydrogen-bonding sequences that were hypothesized to pair into linear H-bonded duplexes. However, instead of undergoing the anticipated pairing, the initially examined three oligomers, 1 and 2a or 2b, differing only in their central αß hybrid dipeptide sequence, do not associate with each other and exhibit distinctly different folding behavior. Experiments based on NMR and mass spectrometry, along with computational studies and systematic inference, reveal that oligomer 1 folds into an expanded ß-turn containing an unusual hybrid α/ß-amino acid sequence composed of glycine and ß-alanine, two α- and ß-amino acid residues that are conformationally most flexible, and peptides 2a and 2b adopt a noncanonical, extended helical conformation and dimerize into double helices undergoing rapid conformational exchange or helix inversion. The different central dipeptide sequences, αß vs ßα, result in drastically different intramolecular H-bonding patterns that are responsible for the observed folding behavior of 1 and 2. The revealed turn and double helix have few natural or synthetic counterparts, and provide novel and unique folding prototypes based on which chiral α- and ß-amino acids are incorporated. The resultant derivatives 1a, 1b, 2c, and 2d follow the same folding and assembling behavior and demonstrate the generality of this system with the formation of expanded ß-turns and double helices with enhanced folding stabilities, hampered helix inversion, as well as defined and dominant helical sense. This work has demonstrated the unique capability of synthetic foldamers in generating structures with fascinating folding and assembling behavior. The revealed systems offer ample opportunity for further structural optimization and applications.

8.
Int Immunopharmacol ; 75: 105811, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31422183

RESUMEN

BACKGROUND: Vitamin D regulates the immune system and affects the outcome of allografts. We investigated the mechanisms underlying the preventative potential of vitamin D in acute cellular rejection (ACR) and infection, and determined its effects on the induction of both T cells and complement. METHODS: A total of 141 patients who received a liver allograft at our center between 2012 and 2016 were enrolled in the study and divided into a vitamin D supplementation group (case group, n = 71) and a non-vitamin D supplementation group (control group, n = 70). Serum was collected in the hours prior to transplantation and within the first month of transplantation. We evaluated the relationship between the serum levels of 25-hydroxyvitamin D ACR, infection, T cells, complement, and graft function. Follow-up was conducted until patient death or June 30, 2018. RESULTS: Vitamin D deficiency was an important independent risk factor for ACR. The incidence of ACR, and bacterial and fungal infection was reduced in patients with vitamin D supplementation. The frequency of Treg, Tmemory, T naïve cells and CD8 + CD28+ T cells (CTL) and the level of complement component 3 were related to ACR in the first month after transplantation. This study showed increased numbers of Treg cells and Tmemory cells and decreased numbers of Naïve cells and CTL in the case group. Vitamin D status was significantly associated with mortality. CONCLUSIONS: Vitamin D supplementation is associated with a lower risk of ACR and infection, suggesting that it may promote immune tolerance towards the liver allografts.

9.
Small ; : e1902551, 2019 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-31423746

RESUMEN

Developing nonprecious electrocatalysts with superior activity and durability for electrochemical water splitting is of great interest but challenging due to the large overpotential required above the thermodynamic standard potential of water splitting (1.23 V). Here, in situ growth of Fe2+ -doped layered double (Ni, Fe) hydroxide (NiFe(II,III)-LDH) on nickel foam with well-defined hexagonal morphology and high crystallinity by a redox reaction between Fe3+ and nickel foam under hydrothermal conditions is reported. Benefiting from tuning the local atomic structure by self-doping Fe2+ , the NiFe(II,III)-LDH catalyst with higher amounts of Fe2+ exhibits high activity toward oxygen evolution reaction (OER) as well as hydrogen evolution reaction (HER) activity. Moreover, the optimized NiFe(II,III)-LDH catalyst for OER (O-NiFe(II,III)-LDH) and catalyst for HER (H-NiFe(II,III)-LDH) show overpotentials of 140 and 113 mV, respectively, at a current density of 10 mA cm-2 in 1 m KOH aqueous electrolyte. Using the catalysts for overall water splitting in two-electrode configuration, a low overpotential of just 1.54 V is required at a benchmark current density of 10 mA cm-2 . Furthermore, it is demonstrated that electrolysis of the water device can be drived by a self-powered system through integrating a triboelectric nanogenerator and battery, showing a promising way to realize self-powered electrochemical systems.

10.
J Cogn Neurosci ; : 1-21, 2019 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-31397614

RESUMEN

Response inhibition is a widely studied aspect of cognitive control that is particularly interesting because of its applications to clinical populations. Although individual differences are integral to cognitive control, so too is our ability to aggregate information across a group of individuals, so that we can powerfully generalize and characterize the group's behavior. Hence, an examination of response inhibition would ideally involve an accurate estimation of both group- and individual-level effects. Hierarchical Bayesian analyses account for individual differences by simultaneously estimating group and individual factors and compensate for sparse data by pooling information across participants. Hierarchical Bayesian models are thus an ideal tool for studying response inhibition, especially when analyzing neural data. We construct hierarchical Bayesian models of the fMRI neural time series, constructing hierarchies across conditions, participants, and ROIs. Here, we demonstrate the advantages of our models over a conventional generalized linear model in accurately separating signal and noise. We then apply our model to go/no-go and stop signal data from 11 participants. We find strong evidence for individual differences in neural responses to going, not going, and stopping and in functional connectivity across the two tasks and demonstrate how hierarchical Bayesian models can effectively compensate for these individual differences while providing group-level summarizations. Finally, we validated the reliability of our findings using a larger go/no-go data set consisting of 179 participants. In conclusion, hierarchical Bayesian models not only account for individual differences but allow us to further understand cognition.

11.
Chem Rev ; 119(15): 9303-9359, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31364835

RESUMEN

With the fast development of nanoscience and nanotechnology in the last 30 years, semiconductor nanowires have been widely investigated in the areas of both electronics and optoelectronics. Among them, representatives of third generation semiconductors, such as ZnO and GaN, have relatively large spontaneous polarization along their longitudinal direction of the nanowires due to the asymmetric structure in their c-axis direction. Two-way or multiway couplings of piezoelectric, photoexcitation, and semiconductor properties have generated new research areas, such as piezotronics and piezo-phototronics. In this review, an in-depth discussion of the mechanisms and applications of nanowire-based piezotronics and piezo-phototronics is presented. Research on piezotronics and piezo-phototronics has drawn much attention since the effective manipulation of carrier transport, photoelectric properties, etc. through the application of simple mechanical stimuli and, conversely, since the design of new strain sensors based on the strain-induced change in semiconductor properties.

12.
ACS Appl Mater Interfaces ; 11(37): 34251-34257, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31448893

RESUMEN

Wearable electronics containing different functional sensors with abilities to meet people's daily needs are highly desirable. Here, a stretchable triboelectric nanogenerator (TENG) for wearable electronics is demonstrated. By stacking two layers of silicone rubbers embedded with silver nanowires (AgNWs) and a Ni foam as electrodes, respectively, the fabricated TENG can serve as a new type of sensor that is wearable, stretchable, skin-friendly, noninvasive, and durable. It can convert mechanical deformation into electric signals. Deformation like stretching and extruding of the TENG results in interlayer rubbing because of inhomogeneous strain, producing triboelectric charges that can induce voltage signals in the electrodes in response to the deformation. On the basis of the principle, a joint sensor based on the TENG is demonstrated, which can generate different output voltages according to the bending degrees of the joint. Furthermore, a three-dimensional sensor integrating three TENGs is fabricated to depict the deformations of different muscle areas. The output voltages of the three TENGs can be simultaneously monitored to reflect the deformation degrees of different muscle areas.

13.
Adv Mater ; : e1902549, 2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-31348590

RESUMEN

Integration of advanced nanogenerator technology with conventional textile processes fosters the emergence of textile-based nanogenerators (NGs), which will inevitably promote the rapid development and widespread applications of next-generation wearable electronics and multifaceted artificial intelligence systems. NGs endow smart textiles with mechanical energy harvesting and multifunctional self-powered sensing capabilities, while textiles provide a versatile flexible design carrier and extensive wearable application platform for their development. However, due to the lack of an effective interactive platform and communication channel between researchers specializing in NGs and those good at textiles, it is rather difficult to achieve fiber/fabric-based NGs with both excellent electrical output properties and outstanding textile-related performances. To this end, a critical review is presented on the current state of the arts of wearable fiber/fabric-based piezoelectric nanogenerators and triboelectric nanogenerators with respect to basic classifications, material selections, fabrication techniques, structural designs, and working principles, as well as potential applications. Furthermore, the potential difficulties and tough challenges that can impede their large-scale commercial applications are summarized and discussed. It is hoped that this review will not only deepen the ties between smart textiles and wearable NGs, but also push forward further research and applications of future wearable fiber/fabric-based NGs.

14.
J Vis ; 19(7): 14, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31323664

RESUMEN

The staircase method has been widely used in measuring perceptual learning. Recently, Zhao, Lesmes, and Lu (2017, 2019) developed the quick Change Detection (qCD) method and applied it to measure the trial-by-trial time course of dark adaptation. In the current study, we conducted two simulations to evaluate the performance of the 3-down/1-up staircase and qCD methods in measuring perceptual learning in a two-alternative forced-choice task. In Study 1, three observers with different time constants (40, 80, and 160 trials) of an exponential learning curve were simulated. Each simulated observer completed staircases with six step sizes (1%, 5%, 10%, 20%, 30%, and 60%) and a qCD procedure, each starting at five levels (+50%, +25%, 0, -25%, and -50% different from the true threshold in the first trial). We found the following results: Staircases with 1% and 5% step sizes failed to generate more than five reversals half of the time; and the bias and standard deviations of thresholds estimated from the post hoc segment-by-segment qCD analysis were much smaller than those from the staircase method with the other four step sizes. In Study 2, we simulated thresholds in the transfer phases with the same time constants and 50% transfer for each observer in Study 1. We found that the estimated transfer indexes from qCD showed smaller biases and standard deviations than those from the staircase method. In addition, rescoring the simulated data from the staircase method using the Bayesian estimation component of the qCD method resulted in much-improved estimates. We conclude that the qCD method characterizes the time course of perceptual learning and transfer more accurately, precisely, and efficiently than the staircase method, even with the optimal 10% step size.

15.
J Exp Psychol Gen ; 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31259601

RESUMEN

The ability to expand and contract one's mental horizons allows people to regulate toward ends that are both distant and near. One challenge that people face when regulating toward distant relative to near ends is the lack of information about detailed specifics. In response, construal level theory (CLT) proposes that people engage in high-level construal-a representational process that highlights the essential properties of events that are invariant across potential instantiations. To tailor responses to more immediate events, however, CLT proposes that people engage in low-level construal-a representational process that highlights idiosyncratic specifics that distinguish events from one another. The present article uses network neuroscience to investigate the neurocognitive mechanisms for these representational processes. While undergoing fMRI, participants were instructed to think about the distant versus near future, and completed tasks that directly manipulated high-level versus low-level construal. Thinking about the distant future and engaging in high-level construal both promoted integration across the network (indexed by global efficiency). Thinking about the near future and engaging in low-level construal promoted segregation within the network (indexed by clustering coefficient). These are the first findings to document how the brain reconfigures to support the expansion versus contraction of one's mental horizons, and provides new insight into the neural mechanisms that help people regulate toward distant versus near ends. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

16.
Nat Prod Res ; : 1-6, 2019 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-31303068

RESUMEN

This study seeks to discover flavonoids from a traditional Chinese herb, Artemisia rupestris L., with synergistic antibacterial effects against multidrug-resistant Staphylococcus aureus. Five flavonoids, artemetin (1), chrysosplenetin (2), pachypodol (3), penduletin (4) and chrysoeriol (5) were obtained by various column chromatographic methods. Their chemical structures were determined on the basis of comprehensive spectroscopic analysis and comparison with literature data. Three of the compounds (2, 4 and 5) exhibited synergistic activity when combined with norfloxacin against SA1199B, an effluxing fluoroquinolone-resistant strain. The fractional inhibitory concentration indices (FICIs) of 2, 4 and 5 in combination with norfloxacin were 0.375, 0.079 and 0.266 respectively, suggesting synergy. Compound 5 also showed synergistic effects against EMRSA-15 and EMRSA-16 when combined with ciprofloxacin and oxacillin exhibiting FICIs of 0.024 and 0.375 respectively. Real time ethidium bromide (EtBr) efflux assay, qRT-PCR and molecular docking were employed to explore the mechanisms of the synergistic effects.

17.
Eur J Med Chem ; 179: 723-735, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31284082

RESUMEN

The biological resistance of methicillin-resistant staphylococcus aureus (MRSA) has pushed synthetic antibiotics to the forefront. To combat the resistance of MRSA, our new effort directed towards the development of novel structural candidates of enone-bridged indole nitroimidazole scaffolds, and wished to shed some light on the combination of some single pharmacophore with different biological activities. Bioassay revealed that the active compound 4b gave a satisfactory inhibition on MRSA (MIC = 1 µg/mL) and could effectively prevent the development of bacterial resistance. Mechanism exploration indicated that molecule 4b could not only intercalate into MRSA deoxyribonucleic acid (DNA), but also permeate MRSA membrane and bind with penicillin-binding protein 2a (PBP2a), then decreased the expression of three relevant genes in MRSA. Furthermore, it was able to be stored and carried by human serum albumin (HSA), and the participation of metal ions in 4b-HSA system was helpful to improve the supramolecular transport behavior. Hybrid 4b also exhibited low cytotoxicity towards normal lung epithelial cell line BEAS-2B.

18.
Neuron ; 103(5): 909-921.e6, 2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31296412

RESUMEN

The ability to group physical stimuli into behaviorally relevant categories is fundamental to perception and cognition. Despite a large body of work on stimulus categorization at the behavioral and cognitive levels, little is known about the underlying mechanisms at the neuronal level. Here, combining mouse auditory psychophysical behavior and in vivo two-photon imaging from the auditory cortex, we investigate how sensory-to-category transformation is implemented by cortical neurons during a stimulus categorization task. Distinct from responses during passive listening, many neurons exhibited emergent selectivity to stimuli near the category boundary during task performance, reshaping local tuning maps; other neurons became more selective to category membership of stimuli. At the population level, local cortical ensembles robustly encode category information and predict trial-by-trial decisions during task performance. Our data uncover a task-dependent dynamic reorganization of cortical response patterns serving as a neural mechanism for sensory-to-category transformation during perceptual decision-making.

19.
Zhongguo Zhong Yao Za Zhi ; 44(12): 2486-2492, 2019 Jun.
Artículo en Chino | MEDLINE | ID: mdl-31359715

RESUMEN

To establish a determination method for the contents of ammonium glycyrrhetate,nardosinone,and curcumin in transdermal receptor liquid of Baimai Ointment,and investigate the percutaneous permeability of Baimai Ointment and the effects of two kinds of penetration enhancers on percutaneous absorption of three components. The contents of ammonium glycyrrhetate,nardosinone,and curcumin in transdermal receptor liquid were determined by high pressure liquid chromatography( HPLC). The vertical modified Franz diffusion cell was used to perform a transdermal experiment in vitro with the abdominal skin of mice( treated and untreated). The transdermal receptor liquid was preferably used to investigate the transdermal absorption rule of the Baimai Ointment and the effect of the penetration enhancer. The results showed that the comprehensive solubility of PEG-ET-NS( 3 ∶3 ∶4) was best among three types of receptor liquid PG-ET-NS( 3 ∶3 ∶4),PEG-ET-NS( 3 ∶3 ∶4),ET-NS( 3 ∶7). PEG-ET-NS was used as the receptor liquid for in vitro transdermal experiments. The cumulative permeation area of ammonium glycyrrhetate,nardosinone and curcumin within 24 h was 5. 73,18. 99,0. 38 µg·cm~(-2)respectively. Taking QEFand ER as comprehensive evaluation indicators of permeation performance,the comprehensive penetration-promoting performance of ammonium glycyrrhizinate: 3% PEG 400-ethanol-normal saline ≈ 1. 19 times( 3%azone) = 1. 94 times( blank); comprehensive penetration-promoting performance of nardosinone: 3% PEG 400-ethanol-normal saline≈1. 28 times( 3% azone) = 1. 37 times( blank); the comprehensive penetration performance of curcumin: 3% PEG 400-ethanol-normal saline≈1. 77 times( 3% azone) ≈3. 42 times( blank). The comprehensive penetration enhancement properties of the two penetration enhancers were as follows: 3% PEG 400-ethanol-normal saline>3%azone>blank. The transdermal absorption curve of ammonium glycyrrhetate,nardosinone and curcumin in Baimai Ointment were consistent with the zero-order equation,indicating that the transdermal absorption process was irrelevant to the concentration of three components,and its was a diffusion process. This experiment provides reference for the study of ointment transdermal preparations.


Asunto(s)
Administración Cutánea , Pomadas/farmacocinética , Absorción Cutánea , Piel , Animales , Ratones , Permeabilidad
20.
Adv Mater ; 31(36): e1902831, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31276258

RESUMEN

Ferroelectric materials use both the pyroelectric effect and piezoelectric effect for energy conversion. A ferroelectric BaTiO3 -based pyro-piezoelectric sensor system is demonstrated to detect temperature and pressure simultaneously. The voltage signal of the device is found to enhance with increasing temperature difference with a sensitivity of about 0.048 V °C-1 and with applied pressure with a sensitivity of about 0.044 V kPa-1 . Moreover, no interference appears in the output voltage signals when piezoelectricity and pyroelectricity are conjuncted in the device. A novel 4 × 4 array sensor system is developed to sense real-time temperature and pressure variations induced by a finger. This system has potential applications in machine intelligence and man-machine interaction.

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