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1.
Small ; : e1907341, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049440

RESUMO

Different from graphene with the highly stable sp2 -hybridized carbon atoms, which shows poor controllability for constructing strong interactions between graphene and guest metal, graphdiyne has a great potential to be engineered because its high-reactive acetylene linkages can effectively chelate metal atoms. Herein, a hydrogen-substituted graphdiyne (HsGDY) supported metal catalyst system through in situ growth of Cu3 Pd nanoalloys on HsGDY surface is developed. Benefiting from the strong metal-chelating ability of acetylenic linkages, Cu3 Pd nanoalloys are intimately anchored on HsGDY surface that accordingly creates a strong interaction. The optimal HsGDY-supported Cu3 Pd catalyst (HsGDY/Cu3 Pd-750) exhibits outstanding electrocatalytic activity for the oxygen reduction reaction (ORR) with an admirable half-wave potential (0.870 V), an impressive kinetic current density at 0.75 V (57.7 mA cm-2 ) and long-term stability, far outperforming those of the state-of-the-art Pt/C catalyst (0.859 V and 15.8 mA cm-2 ). This excellent performance is further highlighted by the Zn-air battery using HsGDY/Cu3 Pd-750 as cathode. Density function theory calculations show that such electrocatalytic performance is attributed to the strong interaction between Cu3 Pd and CC bonds of HsGDY, which causes the asymmetric electron distribution on two carbon atoms of CC bond and the strong charge transfer to weaken the shoulder-to-shoulder π conjugation, eventually facilitating the ORR process.

2.
Dalton Trans ; 49(7): 2234-2243, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32003383

RESUMO

A new oxofluoride Co15F2(TeO3)14 has been prepared by optimized hydrothermal synthesis involving a complex mineralization process. The crystal structure consists of a three-dimensional network of CoO5(O,F) octahedra, distorted CoO5 square pyramids, TeO3 trigonal pyramids and grossly distorted TeO3+3 octahedra, which are linked by sharing corners and edges. The Te(iv) lone pairs are accommodated within novel pyritohedron-shaped [(TeO3)14]28- units. This special framework provides a much larger free space that allows Te atoms to vibrate with a large amplitude, which leads to extremely low lattice thermal conductivity. Magnetic susceptibility data for Co15F2(TeO3)14 show antiferromagnetic ordering below 9.6 K with a substantial orbital component to the effective magnetic moment. An S = 3/2 honeycomb-like spin network was carefully analyzed by experimental techniques and first principles calculations.

3.
Transfusion ; 60(2): 326-333, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31912898

RESUMO

BACKGROUND: In China, there is a rising concern on the increasing trends of HIV infections in high-risk groups, who make blood donations that might potentially challenge the blood safety. Analyses on current risk factors for HIV infection among Chinese blood donors are urgently needed for developing effective strategies to defer high-risk donors and to warrant the safety of the blood supply. STUDY DESIGN AND METHODS: We recruited 313 HIV-positive and 762 HIV-negative donors from seven study sites in China and evaluated donor demographic characteristics, current medical and behavioral risk factors associated with HIV infection in a case-control survey. Univariable analyses examined the relationship between HIV infection and donor and donation characteristics, medical and behavioral risks, living conditions, and lifestyles. Multivariable logistic regression analyses evaluated the association between selected individual risks and HIV infection. Regression tree analysis was used to select covariates correlated with both HIV infection and individual risks and thus need to be controlled for in logistic regression models. RESULTS: Being a man who has sex with men was associated with the highest odds of HIV infection. Not using a condom, having sex with HIV-infected individuals, having sex partners with sexually transmitted diseases (STDs), having more than two concurrent sex partners, or having an STD were all associated with more than five times higher odds of having HIV. Having remunerated sex was associated with a 2.4 increased odds of having HIV infection. CONCLUSION: High-risk sexual behaviors were among the major risks for HIV infection among Chinese blood donors.

4.
Medicine (Baltimore) ; 99(4): e18721, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977862

RESUMO

To evaluate the incidence of ecchymosis combined with postinflammatory hyperpigmentation (ECPH) over the course of 10 sessions of acupuncture therapy and to examine associated factors.An observational study was conducted from March 7, 2017 through March 6, 2018. This study included a total of 167 subjects and 326 bodily locations where acupuncture needles had been inserted. A 1-page questionnaire that included 14 items was used to collect patient data. The information collected was used to determine the incidence of ECPH. Chi-square tests were used to observe the associations between ECPH and demographic characteristics, dermatologic features, acupuncture-related factors, and other associated factors. Cox proportional hazards regression models were applied to calculate hazard ratios for ECPH among subjects treated with various frequencies of acupuncture and needles that differed in diameter.Although 186 subjects were initially enrolled, the study ultimately included 167 subjects and 326 bodily locations at which acupuncture needles were inserted. Over 10 sessions of acupuncture, ECPH was observed in 117 (70.06%, 117/167) subjects and 221 (67.79%, 221/326) bodily locations. Factors found to be associated with ECPH included: frequency of acupuncture, diameter of acupuncture needle, total number of acupuncture sessions, and bodily location at which acupuncture was administered (P < .05). Among subjects who received >2 acupuncture sessions per week, a higher frequency of acupuncture was associated with increased incidence of ECPH. Thicker acupuncture needle diameter was associated with a higher incidence of ECPH.The incidence of acupuncture-associated ECPH among the subjects included in the study was high. There were significant associations between ECPH and higher frequency of acupuncture as well as thicker diameter of acupuncture needles. Additional studies are required to confirm the findings.Trial registration number: AMCTR-OOC-17000109.


Assuntos
Terapia por Acupuntura/efeitos adversos , Equimose/etiologia , Hiperpigmentação/etiologia , Terapia por Acupuntura/métodos , Terapia por Acupuntura/estatística & dados numéricos , Adulto , Idoso , Equimose/epidemiologia , Feminino , Humanos , Hiperpigmentação/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Inquéritos e Questionários
5.
World Neurosurg ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31634623

RESUMO

BACKGROUND: Due to suboptimal pain control under conventional local anesthesia, percutaneous endoscopic interlaminar discectomy is typically performed under general anesthesia. The purpose of this study was to develop a stepwise approach of local anesthesia for endoscopic interlaminar discectomy and evaluate its efficacy. METHODS: A stepwise local anesthesia was developed, which mainly includes 3 steps: conventional local anesthesia from skin to laminae, epidural injection, and nerve root block. From June 2015 to May 2017, consecutive patients who underwent endoscopic interlaminar discectomy were included. Local anesthesia or general anesthesia was used based on patients' preference. Anesthetic effectiveness was evaluated as excellent, good, or poor, and adverse events were recorded. Hospitalization expense was compared between the 2 groups. Clinical outcomes were assessed using the Visual Analog Scale and the Oswestry Disability Index. RESULTS: There were 98 patients included in the study. Among them, 48 received stepwise local anesthesia and the other 50 received general anesthesia. In the stepwise local anesthesia group, 40 (83.3%) patients rated anesthetic effectiveness as excellent, 7 (14.6%) as good, and 1 (2.1%) as poor. Nine patients had complications that may be associated with local anesthesia, including dyspnea, temporary paresis of legs, and temporary worsened dysesthesia or numbness in legs. After surgery, the patients' leg pain and Oswestry Disability Index significantly improved in both groups. On average, hospitalization expense was approximately 20% less when local anesthesia was used, as compared with using general anesthesia. CONCLUSIONS: The stepwise local anesthesia can achieve satisfactory pain control and seems to be a good choice for endoscopic interlaminar discectomy.

6.
Int J Oral Sci ; 11(3): 31, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31575850

RESUMO

By removing a part of the structure, the tooth preparation provides restorative space, bonding surface, and finish line for various restorations on abutment. Preparation technique plays critical role in achieving the optimal result of tooth preparation. With successful application of microscope in endodontics for >30 years, there is a full expectation of microscopic dentistry. However, as relatively little progress has been made in the application of microscopic dentistry in prosthodontics, the following assumptions have been proposed: Is it suitable to choose the tooth preparation technique under the naked eye in the microscopic vision? Is there a more accurate preparation technology intended for the microscope? To obtain long-term stable therapeutic effects, is it much easier to achieve maximum tooth preservation and retinal protection and maintain periodontal tissue and oral function health under microscopic vision? Whether the microscopic prosthodontics is a gimmick or a breakthrough in obtaining an ideal tooth preparation should be resolved in microscopic tooth preparation. This article attempts to illustrate the concept, core elements, and indications of microscopic minimally invasive tooth preparation, physiological basis of dental pulp, periodontium and functions involved in tool preparation, position ergonomics and visual basis for dentists, comparison of tooth preparation by naked eyes and a microscope, and comparison of different designs of microscopic minimally invasive tooth preparation techniques. Furthermore, a clinical protocol for microscopic minimally invasive tooth preparation based on target restorative space guide plate has been put forward and new insights on the quantity and shape of microscopic minimally invasive tooth preparation has been provided.


Assuntos
Estética Dentária , Preparo do Dente , Consenso
7.
Dent Mater J ; 38(6): 884-891, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31611496

RESUMO

This study investigated the role played by different pH environments in the deterioration of bonds between Y-TZP and Ti-6Al-4V. One hundred and thirty-five specimens were randomly assigned to one of the following storage media at 37°C: (1) distilled water, pH 6.9, DW; (2) acidic solution, pH 1-2, CS; and (3) alkaline solution, pH 10-11, KS. Shear bond strength (SBS) tests were carried out at the 4-, 14-, and 30-day storage time intervals. The morphology characteristics and elements distribution of the fracture surfaces were analyzed. CS-30 showed the lowest mean SBS and the least amount of residual cement on the Ti-6Al-4V surface after the SBS tests. Bond strength tended to decrease with increasing storage time for the acidic group. Alkaline and neutral media showed little influence on the SBS of Y-TZP to Ti-6Al-4V in 30 days. Acidic environments should be properly avoided to obtain reliable long-term bonding strength between Ti-6Al-4V and Y-TZP.


Assuntos
Titânio , Zircônio , Concentração de Íons de Hidrogênio , Teste de Materiais , Propriedades de Superfície
8.
J Colloid Interface Sci ; 555: 714-721, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416026

RESUMO

High-efficiency separation of niacin (NIA) and nicotinamide (NIC) still faces large challenge up to date. In this work, a stable zirconium-based metal-organic framework (DUT-67) was used to adsorb and separate NIA and NIC in aqueous solutions. The adsorption capacities for NIA and NIC at the concentration ratio of 1:1 were 110.2 mg g-1 and 11.2 mg g-1, respectively. Further study indicates that low ratio of NIA/ NIC is in favor of the separation. High temperature can restrain the adsorptions of NIA and NIC but promote the separation. Besides, DUT-67 can be well regenerated via a simple method. Mechanism analysis indicates that electrostatic interaction plays a critical role in the separation of these vitamins.

9.
Med Eng Phys ; 71: 91-97, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31311692

RESUMO

Microelectrode arrays (MEAs) allow the investigation of the pharmacological and toxicological effects of chemicals on cultured neuronal networks. Understanding the functional connections between neurons and the resulting neuronal networks is important for evaluating drugs that affect synaptic transmission. Therefore, we acutely treated a mature cultured neuronal network on MEAs with accumulating amounts of glutamate and recorded their altered electrophysiology. Subsequently, a cross-covariance analysis was applied to process the spiking activity in the network and to evaluate the connections between neurons. Finally, graph theory was used to assess the functional network properties under acute glutamate treatment. Our data demonstrated that glutamate increased the similarity, connectivity weight, density, and largest-component size of the functional network. In addition, the small-world network topology was altered after glutamate treatment. Our results indicate that the graph theory can advance our understanding of the pharmacological significance of neurotransmitters on neuronal networks.

10.
Zhongguo Zhong Yao Za Zhi ; 44(12): 2566-2571, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359725

RESUMO

This study was to investigate the mechanism of safflower yellow injection for regulating inflammatory response against myocardial ischemia-reperfusion injury( MIRI) in rats. Male Wistar rats were randomly divided into sham operation group,model group,Hebeishuang group,safflower yellow injection high,medium and low dose groups. MIRI model was established by ligating left anterior descending coronary artery. Myocardial histopathological changes were observed by HE staining; myocardial infarct size was detected by TTC staining; content and changes of tumor necrosis factor-α( TNF-α) and interleukin-6( IL-6),serum creatine kinase( CK),aspartate aminotransferase( AST),and lactate dehydrogenase( LDH) were detected by biochemical method or enzyme-linked immunosorbent assay( ELISA). Western blot assay was used to detect the protein expression of Toll-like receptor 4( TLR4) and nuclear factor-κB( NF-κB p65) in myocardial tissues. The results showed that as compared with the sham operation group,the myocardial arrangement of the model group was disordered,with severe edemain the interstitial,significantly increased area of myocardial infarction,increased activities of AST,CK and LDH in serum,and significantly increased contents of TNF-α and IL-6; the expression levels of TLR4 and NF-κB( p65) protein in myocardial tissues were also increased. As compared with the model group,the myocardial tissues were arranged neatlyin the Hebeishuang group and safflower yellow injection high,medium and low dose groups; the edema was significantly reduced; the myocardial infarct size was significantly reduced; the serum AST,CK,LDH activity and TNF-α,IL-6 levels were significantly decreased,and the expression levels of TLR4 and NF-κB( p65) protein in myocardial tissues were decreased. As compared with the Hebeishuang group,the myocardial infarct size was larger in the safflower yellow injection high,medium and low dose groups; the activities of AST,CK and LDH in serum and the contents of TNF-α and IL-6 in serum were higher,but there was no statistically significant difference in the expression levels of TLR4 and NF-κB( p65) protein in tissues. It is suggested that safflower yellow injection has a significant anti-MIRI effect,and its mechanism may be related to the regulation of TLR-NF-κB pathway to inhibit inflammatory response.


Assuntos
Anti-Inflamatórios/farmacologia , Chalcona/análogos & derivados , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Aspartato Aminotransferases/sangue , Chalcona/farmacologia , Creatina Quinase/sangue , Interleucina-6/metabolismo , L-Lactato Desidrogenase/sangue , Masculino , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
11.
ACS Nano ; 13(6): 7270-7280, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31184851

RESUMO

Aqueous zinc-ion batteries (ZIBs) possess energy storages advantages, including low cost, high safety, and durable lifetimes. Materials are worth exploring to achieve high-performance batteries. Although Bi2S3 is predicted to be highly capable for energy storage, it has never been used in aqueous ZIBs due to the structure degradation. Herein, we apply Bi2S3 in aqueous ZIBs and develop an ionic liquid enhanced poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) coating to perfectly stabilize the Bi2S3 electrode, which plays three roles of providing high conductivity, inhibiting grain pulverization and sulfur dissolution, and acting as an artificial solid electrolyte interphase. The synergistic merits of the desirable capacity of Bi2S3 and a versatile polymer provide a capacity of 275 mAh g-1 and excellent cycling stability up to 5300 cycles with 95.3% retention. A reversible conversion mechanism into hexagonal ZnS is revealed by investigation of a variety of spectra. The prepared quasi-solid battery based on a high concentration salt electrolyte/polyacrylamide hydrogel exhibits a high energy density (315 Wh kg-1) and long-term cyclability over 5300 cycles. For demonstration, a single battery can power a digital hygrometer thermometer for more than 14 h 48 min. This work highlights a ground-breaking demonstration of incorporating structural integrity with stable interfacial chemistry.

12.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(3): 229-235, 2019 Jun 01.
Artigo em Chinês | MEDLINE | ID: mdl-31218853

RESUMO

Tooth preparation is the primary and core operation technique for dental esthetic restoration treatment, due to its effect of providing restoration space, bonding interfaces and marginal lines for dental rehabilitation after tooth tissue reduction. The concept of microscopic minimal invasive dentistry put forward the issue of conducting high-quality tooth preparation, conserve tooth-structure, protect vital pulp and periodontal tissue simultaneously. This study reviewed the concepts, physiology background, design and minimal invasive microscopic tooth preparation, and in the meantime, individualized strategies and the two core elements of tooth preparation (quantity and shape) are listed.


Assuntos
Porcelana Dentária , Estética Dentária , Preparo do Dente , Restauração Dentária Permanente
13.
Mol Med Rep ; 20(1): 103-110, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31115567

RESUMO

Hepatitis B virus (HBV) vaccination is regarded as the most economical and effective method for the prevention and control of HBV infection, a major global health problem. Previous studies have suggested that there may be sex­specific differences regarding the immune response to the HBV vaccine in humans; however, the mechanisms associated with these sex­specific differences are yet to be elucidated. In the present study, sex­based immunological differences in mice following HBV vaccination were investigated to determine the mechanisms underlying sexual dimorphism, with the aim of identifying potential targets for clinical intervention. Balb/c mice (n=6) were vaccinated intramuscularly on 3 different days (days 0, 14 and 28) with the HBV vaccine. Sera were analyzed via ELISA for the presence of HBV surface antigen (HBsAg)­specific immunoglobulin G (IgG), and of different IgG subtypes, 3 weeks following the third injection. Enzyme­linked immunosorbent spot assays were conducted to determine interleukin­4/interferon­Î³ secretion. Immunological memory stimulated by the vaccine was detected via flow cytometry analysis and ELISA 1 week following the booster immunization. The seroconversion of the treated female group was higher compared with the male group at one week following the second vaccination. Female mice exhibited significantly increased HBsAg antibody titers compared with males at 1­5 weeks following the third vaccination. Sera obtained from vaccinated female mice exhibited markedly increased titers of IgG1 and IgG2b compared with those from male mice. Furthermore, female mice exhibited elevated cytotoxic T lymphocyte responses and immune memory. Collectively, the results of the present study indicated that sex­based immunological differences affected the dynamics and characteristics of the immune response in mice immunized with the HBV vaccine.


Assuntos
Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/imunologia , Hepatite B/imunologia , Imunidade Celular/genética , Animais , Feminino , Hepatite B/sangue , Hepatite B/prevenção & controle , Hepatite B/virologia , Vacinas contra Hepatite B/farmacologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Humanos , Imunidade Celular/imunologia , Imunização Secundária , Imunoglobulina G/imunologia , Camundongos , Células Th1/imunologia , Vacinação
14.
Opt Express ; 27(6): 8808-8818, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31052693

RESUMO

We demonstrate a practical method that is used to generate on-demand first- and higher-order cylindrical vector beams, in the 1550 nm band, directly from an all polarization maintaining mode-locked Er-fiber laser. On demand typical 1st order CVBs, including the radially and azimuthally polarized beams, can be easily achieved by properly adjusting the angle of a half-wave plate with respect to the fast axis of the vortex wave plate. The spatial beam mode can be flexibly switched with no disturbance on the time domain mode-locking output. The laser outputs the desired vector beams at 1571 nm with a spectral bandwidth at full-width at half-maximum of 32 nm. The mode-locked laser pulses have a repetition rate of 74.9 MHz. Moreover, the proposed method can be easily extended to create higher-order CVBs. Our research provides a convenient way to generate ultrafast pulses in highly flexible-controlled structured modes, which is essential for optical fabrication and light trapping applications.

15.
Neurosci Bull ; 35(5): 826-840, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31062334

RESUMO

Motor timing is an important part of sensorimotor control. Previous studies have shown that beta oscillations embody the process of temporal perception in explicit timing tasks. In contrast, studies focusing on beta oscillations in implicit timing tasks are lacking. In this study, we set up an implicit motor timing task and found a modulation pattern of beta oscillations with temporal perception during movement preparation. We trained two macaques in a repetitive visually-guided reach-to-grasp task with different holding intervals. Spikes and local field potentials were recorded from microelectrode arrays in the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. We analyzed the association between beta oscillations and temporal interval in fixed-duration experiments (500 ms as the Short Group and 1500 ms as the Long Group) and random-duration experiments (500 ms to 1500 ms). The results showed that the peak beta frequencies in both experiments ranged from 15 Hz to 25 Hz. The beta power was higher during the hold period than the movement (reach and grasp) period. Further, in the fixed-duration experiments, the mean power as well as the maximum rate of change of beta power in the first 300 ms were higher in the Short Group than in the Long Group when aligned with the Center Hit event. In contrast, in the random-duration experiments, the corresponding values showed no statistical differences among groups. The peak latency of beta power was shorter in the Short Group than in the Long Group in the fixed-duration experiments, while no consistent modulation pattern was found in the random-duration experiments. These results indicate that beta oscillations can modulate with temporal interval in their power mode. The synchronization period of beta power could reflect the cognitive set maintaining working memory of the temporal structure and attention.

16.
Biomed Res Int ; 2019: 7630601, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139651

RESUMO

Synechococcus elongatus PCC 7942 (S. elongatus PCC 7942) is a model cyanobacteria species for circadian clock mechanism studies. It has also been widely used as a bioreactor to produce biofuels and other metabolic products. Quantitative real-time PCR (qPCR) technology is the most commonly used method for studying the expression of specific genes, in which the relative expression level of target genes is calibrated by stably expressed internal reference genes. In this work, we examined the expression of nine candidate reference genes in time-course samples of S. elongatus PCC 7942 under no treatment (control), NaCl-stress conditions, H2O2-stress conditions, and high light-stress conditions. Based on the qPCR amplification parameters, the stability ranking of these candidate reference genes was established by three statistical software programs, geNorm, NormFinder, and BestKeeper. Considering all the stress conditions or high light stress alone, the results showed that the combination of prs and secA was the best choice for the double reference gene calibration method by qPCR. The combination of secA and ppc, rimM and rnpA, rnpA, and ilvD was most stable under no treatment, NaCl-stress conditions, and H2O2-stress conditions, respectively. rimM was stable under only special conditions and should be carefully chosen. 16S and rnpB were not suitable as internal reference genes for S. elongatus PCC 7942 qPCR experiments under all experimental conditions. To validate the above results, a cyanobacterial core clock gene, kaiC, was used to evaluate the actual performance of the optimized reference genes by qPCR, as well as the worst reference genes under different stress conditions. The results indicated that the best reference gene yielded more accurate calibration results for qPCR experiments carried out in S. elongatus PCC 7942 time-course samples.


Assuntos
Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Estresse Fisiológico/genética , Synechococcus/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Padrões de Referência , Reprodutibilidade dos Testes , Software
17.
Polymers (Basel) ; 11(4)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30960606

RESUMO

In this paper, bovine serum albumin (BSA)-imprinted calcium alginate (CaAlg) hydrogel membrane was prepared using BSA as a template, sodium alginate (NaAlg) as a functional monomer, and CaCl2 as a cross-linker. The thickness of the CaAlg membrane was controlled by a glass rod enlaced with brass wires (the diameter was 0.1, 0.2, 0.3, 0.4, and 0.5 mm). The swelling properties of the CaAlg membranes prepared with different contents of NaAlg were researched. Circular dichroism indicated that the conformation of BSA did not change during the preparing and eluting process. The thinner the CaAlg hydrogel membrane was, the larger the adsorption capacity and the higher the imprinting efficiency of the CaAlg. The maximum adsorption capacity of molecularly imprinted polymer (MIP) and non-imprinted CaAlg hydrogel membrane (NIP) was 38.6 mg·g-1 and 9.2 mg·g-1, respectively, with an imprinting efficiency of 4.2. The MIP was loaded on the electrode to monitor the selective adsorption of BSA by voltammetry curve.

18.
J Neural Eng ; 16(3): 036011, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30822756

RESUMO

OBJECTIVE: For intracortical neurophysiological studies, spike sorting is an important procedure to isolate single units for analyzing specific functions. However, whether spike sorting is necessary or not for neural decoding applications is controversial. Several studies showed that using threshold crossings (TC) instead of spike sorting could also achieve a similar satisfactory performance. However, such studies were limited in similar behavioral tasks, and the neural signal source mainly focused on the motor-related cortical regions. It is not certain if this conclusion is applicable to other situations. Therefore, we compared the performance of TC and spike sorting in neural decoding with more comprehensive paradigms and parameters. APPROACH: Two rhesus macaques implanted with Utah or floating microelectrode arrays (FMAs) in motor or sensory-related cortical regions were trained to perform a motor or a sensory task. Data from each monkey were preprocessed with three different schemes: TC, automatic sorting (AS), and manual sorting (MS). A support vector machine was used as the decoder, and the decoding accuracy was used for evaluating the performance of three preprocessing methods. Different neural signal sources, different decoders, and related parameters and decoding stability were further tested to systematically compare three preprocessing methods. MAIN RESULTS: TC could achieve a similar (-4.5 RMS threshold) or better (-3.0 RMS threshold) decoding performance compared to the other two sorting methods in the motor or sensory tasks even if the neural signal sources or decoder-related parameters were changed. Moreover, TC was much more stable in neural decoding across sessions and robust to changes of threshold. SIGNIFICANCE: Our results indicated that spike-firing patterns could be stably extracted through TC from multiple cortices in both motor and sensory neural decoding applications. Considering the stability of TC, it might be more suitable for neural decoding compared to sorting methods.

19.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(2): 114-119, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30782271

RESUMO

OBJECTIVE: To investigate the risk factors for brain injury in preterm infants by a multicenter epidemiological investigation of brain injury in hospitalized preterm infants in Anhui, China. METHODS: Preterm infants who were hospitalized in the department of neonatology in 9 hospitals of Anhui Neonatal Collaboration Network between January 2016 and January 2017 were enrolled as subjects. The data of maternal pregnancy and clinical data of preterm infants were collected, and the logistic regression model was used to analyze the risk factors for brain injury in preterm infants. RESULTS: A total of 3 378 preterm infants were enrolled. Of the 3 378 preterm infants, 798 (23.56%) had periventricular-intraventricular hemorrhage (PVH-IVH), and 88 (2.60%) had periventricular leukomalacia (PVL). Intrauterine distress, anemia, hypoglycemia and necrotizing enterocolitis (NEC) were risk factors for PVH-IVH (OR=1.310, 1.591, 1.835, and 3.310 respectively; P<0.05), while a higher gestational age was a protective factor against PVH-IVH (OR=0.671, P<0.05). PVH-IVH, NEC and mechanical ventilation were risk factors for PVL (OR=4.017, 3.018, and 2.166 respectively; P<0.05), and female sex and use of pulmonary surfactant were protective factors against PVL (OR=0.514 and 0.418 respectively; P<0.05). CONCLUSIONS: Asphyxia/anoxia, infection/inflammation, mechanical ventilation, anemia and hypoglycemia may increase the risk of brain injury in preterm infants.


Assuntos
Lesões Encefálicas , Hemorragia Cerebral , China , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Leucomalácia Periventricular
20.
J Biomed Mater Res A ; 107(6): 1132-1142, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30597721

RESUMO

Compositions of resin composite exhibit cytotoxicity, especially Triethylene-glycol-dimethacrylate (TEGDMA), yet the underlying mechanisms and its relationship with filler content are poorly understood. Here, specimens of five composites (VITA LC, VITA ZETA, Z350, Filtek P60, and AP-X), containing different filler size and weight, were immersed into culture medium for 72 h. After TEGDMA quantification, the resin composite eluates were used to incubate HGFs. Cellular viability was evaluated. Total reactive oxygen species (ROS) and mitochondrial ROS were detected to assess oxidative stress. Adenosine triphosphate and cytochrome c oxidase (CcO) activity, mitochondrial membrane potential and morphology, mitochondrial biogenesis regulators were analyzed to evaluate mitochondrial functions. Results showed that TEGDMA release negatively correlated to filler size and weight of tested composites. Although cell viability reduction was not significant, total and mitochondrial ROS production showed a positive relationship with the amount of TEGDMA in composite eluates. Furthermore, the expression of mitochondrial biogenesis markers and mitochondrial fusion protein, were markedly elevated in TEGDMA rich eluates, especially in VITA-LC group, shown as elongated mitochondrial morphology and aberrant mitochondrial functions. Overall, TEGDMA could elute easier from those resin composites with less filler content and cause oxidative stress in HGFs via mitochondria dysregulation. These data can be instructive to optimize the synthesis of resin composites from the perspective of biocompatibility. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1132-1142, 2019.

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