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1.
Small ; 20(16): e2307792, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38037483

ABSTRACT

A high-throughput ion beam sputtering system is used to synthesize compositional gradient superlattice-like (SLL) thin film libraries of Ge-Sb-Te alloys over the entire phase diagram. The optical properties and structural evolution of the Ge-Sb-Te combinatorial SLL thin film are investigated. A systematic screening over the annealing temperature, annealing time, and modulation period has elucidated the critical factors that affect the stability of the metastable phase and optical properties. It is found that amorphous stability and optical constant are highly dependent on the modulation period and chemical composition of the thin film. This data-driven approach offers new perspectives for accelerating the development of new materials with excellent optical and amorphous stability and for exploring their mechanisms, by greatly expanding the dataset of Ge-Sb-Te alloys with SLL structures through high-throughput experiments.

2.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 02.
Article in English | MEDLINE | ID: mdl-37259376

ABSTRACT

Isoxazoles and isoxazolines are five-membered heterocyclic molecules containing nitrogen and oxygen. Isoxazole and isoxazoline are the most popular heterocyclic compounds for developing novel drug candidates. Over 80 molecules with a broad range of bioactivities, including antitumor, antibacterial, anti-inflammatory, antidiabetic, cardiovascular, and other activities, were reviewed. A review of recent studies on the use of isoxazoles and isoxazolines moiety derivative activities for natural products is presented here, focusing on the parameters that affect the bioactivity of these compounds.

3.
Europace ; 25(6)2023 06 02.
Article in English | MEDLINE | ID: mdl-37337705

ABSTRACT

AIMS: Left bundle branch pacing (LBBP) maintains left ventricular synchrony but induces right ventricular conduction delay (RVCD). Although anodal-ring capture (ARC) during bipolar LBBP improves RVCD, it is not achieved in all patients receiving LBBP. This study aimed to analyze the factors influencing ARC implementation. METHODS AND RESULTS: Patients receiving LBBP with intraoperative ARC testing were enrolled. Electrocardiographic parameters were measured, including stimulus-to-QRS duration (stim-QRSd), stimulus-to-left/right ventricular activation time (stim-LVAT/RVAT), and V6-V1 interpeak interval. The distribution of lead-tip sites was described as the corrected longitudinal and lateral distance (longit-/lat-dist). Relative angles of the LBBP lead were measured. Echocardiography in short-axis view was used to measure the intraseptal lead length. Intergroup comparisons, correlation analysis, and stepwise logistic regression were performed. In total, 105 patients were included, among which 65 (62%) patients achieved ARC at a pacing output ≤ 5.0 V/0.5 ms (average 3.1 V/0.5 ms). Anodal-ring capture further shortened the stim-QRSd by 13.1 ± 7.5 ms. Better unipolar-ring (cathodal) threshold and R-wave sensing in LBBP-ARC group indicated the critical role of ring-septum contact in ARC. Longer corrected longit-dist and shorter corrected lat-dist of lead-tip sites were positively correlated with higher success likelihood of ARC, likely due to the greater relative angle in which the lead enters the septum and consequently the longer intraseptal lead length and better ring-septum contact. CONCLUSION: This study elucidated the factors affecting the success likelihood of LBBP-ARC. These findings improve the understanding of LBBP-ARC, providing references for future research and clinical practice.


Subject(s)
Bundle of His , Pacemaker, Artificial , Humans , Cardiac Pacing, Artificial/methods , Heart Conduction System , Electrocardiography/methods
5.
Heart Rhythm ; 20(2): 217-223, 2023 02.
Article in English | MEDLINE | ID: mdl-36347456

ABSTRACT

BACKGROUND: Left bundle branch pacing (LBBP) is an alternative strategy for His-bundle pacing (HBP); however, little is known about tricuspid regurgitation (TR) deterioration after LBBP implantation. OBJECTIVES: The purpose of this study was to characterize the incidence of post-LBBP TR deterioration and identify predicting factors, especially lead position parameters. METHODS: Patients who received LBBP were continuously enrolled from January 2018 to August 2020. The progression of TR and the anatomic position of LBBP were characterized by echocardiography. RESULTS: A total of 89 patients were enrolled and assigned to 2 subgroups based on the degree of TR before LBBP implantation: 58 (65.2%) with relatively normal tricuspid valve (TV) function (grade 0/1 subgroup: with none/trivial or mild TR) and 31 (34.8%) with more severe TR (grade 2/3 subgroup: with moderate or severe TR). At 19.0 ± 6.5 months of follow-up, 29 patients (32.6%) had TR deterioration, and 23 of them were in the grade 0/1 subgroup. In the grade 0/1 subgroup, patients with TR deterioration had a shorter distance between the lead-implanted site and TV (Lead-TA-dist) than those without TR (19.0 ± 7.6 vs 23.9 ± 5.4; P = .006). The receiver operating characteristic (ROC) curve (area under the curve 0.721; 95% confidence interval [CI] 0.575-0.867; P = .005) indicated the favorable efficacy of Lead-TA-dist for predicting TR deterioration after LBBP. Lead-TA-dist ≤16.1 mm was independently associated with TR deterioration after LBBP (hazard ratio 0.20; 95% CI 0.06-0.76; P = .017). CONCLUSION: TR was a common complication of LBBP implantation. In patients with none/trivial or mild TR, Lead-TA-dist ≤16.1 mm was an independent predictor of TR deterioration after LBBP implantation.


Subject(s)
Pacemaker, Artificial , Tricuspid Valve Insufficiency , Humans , Tricuspid Valve Insufficiency/diagnosis , Tricuspid Valve Insufficiency/etiology , Pacemaker, Artificial/adverse effects , Cardiac Pacing, Artificial/adverse effects , Tricuspid Valve/diagnostic imaging , Tricuspid Valve/surgery , Time Factors , Bundle of His , Treatment Outcome , Electrocardiography
6.
Front Physiol ; 13: 996640, 2022.
Article in English | MEDLINE | ID: mdl-36187788

ABSTRACT

Background: Left bundle branch pacing (LBBP) is an alternative strategy for His bundle pacing (HBP). This study aimed to analyze the long-term performance of LBBP and the potential factors affecting long-term cardiac function. Methods: Patients with LBBP were continuously enrolled from January 2018 to August 2020. Pacing parameters, electrocardiogram (ECG), and echocardiography were collected. The anatomic position of LBBP leads was described by echocardiographic and fluoroscopic parameters. Results: A total of 91 patients with a median follow-up of 18 months were enrolled. Most patients maintained stable pacing parameters during follow-up. The intra-septal position of the 3830 lead also remained stable as the distance from the lead tip to the left surface of the ventricular septum was 0.4 (0, 1.4) mm. The overall level of left ventricular ejection fraction (LVEF) slightly increased. 59 patients had improved LVEF (∆LVEF > 0), while 28 patients had unchanged or reduced LVEF (∆LVEF ≤ 0). The declines of baseline LVEF, ∆ Paced QRSd, and corrected longitudinal distance (longit-dist) of lead-implanted site correlated with LVEF improvement, and these three factors had negative linear correlations with ∆LVEF. Patients with tricuspid valve regurgitation (TVR) deterioration had longer follow-up duration (20.5 vs. 15.0 months, p = 0.01) and shorter Lead-TVA-dist (18.6 vs. 21.6 mm, p = 0.04) than those without TVR deterioration. Conclusion: Patients with LBBP generally remained stable in pacing performance, anatomic lead positions, and cardiac function in long-term follow-up. Baseline LVEF, ∆ Paced QRSd, and corrected longit-dist might be associated with potential LVEF decrease, which required further confirmation.

7.
Colloids Surf B Biointerfaces ; 219: 112819, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36137333

ABSTRACT

Bone loss in inflammatory disorders such as osteomyelitis, septic arthritis, and periodontitis is caused by excessive osteoclastic activity. Meanwhile, reactive oxygen species (ROS) have been identified as contributors to osteoclast differentiation, and the application of ROS scavengers has emerged as a promising strategy to protect against bone loss. Recently, resveratrol (RSV), a polyphenolic phytoalexin, has been demonstrated to inhibit osteoclastogenesis by scavenging ROS; however, the application of RSV as an antioxidant is limited by its low water solubility, structural instability, and short elimination half-life. In this study, we developed a PEGylated cyclodextrin (CD)-based nanoplatform (PCP) for local delivery of RSV as nanomicelles (RSV-NMs). In addition, polymer functionalization with phenylboronic acid ester in RSV-NMs successfully achieved ROS-responsive release of RSV. The RSV-NMs in a well-dispersed state possessed good biocompatibility as well as improved solubility and stability compared with RSV compound. In vitro, RSV-NMs significantly inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells and suppressed F-actin (filamentous actin) ring formation. Additionally, the mRNA expressions of osteoclastic marker genes, including matrix metalloprotein-9 (MMP-9), nuclear factor of activated T cells 1 (NFATc1), TRAP, and cathepsin K, were consequently downregulated in the presence of RSV-NMs. In vivo, RSV-NMs provided protection against LPS-induced bone destruction, as evidenced by a decreased number of osteoclasts, increased bone density, and reduced area of bone resorption. Taken together, these results indicate that our ROS-responsive RSV-NMs can be employed as a potential therapeutic agent for the treatment of inflammatory osteolysis.

8.
Front Physiol ; 13: 912126, 2022.
Article in English | MEDLINE | ID: mdl-35991167

ABSTRACT

Background: Left bundle branch area pacing (LBBAP) has become a safe and effective option for heart failure (HF) patients indicated for cardiac resynchronization therapy (CRT) and/or ventricular pacing, yet the response rate was only 70%. Repolarization parameters were demonstrated to be associated with cardiac mechanics and systolic function. This study aimed to investigate the effects of LBBAP on repolarization parameters and the potential association between those parameters and echocardiographic response. Methods and results: A total of 59 HF patients undergoing successful LBBAP were consecutively included. QTc, Tpeak-Tend (TpTe), and TpTe/QTc were measured before and after the implantation. The results turned out that the dispersion of ventricular repolarization (DVR) improved after LBBAP among the total population. Although trends of repolarization parameters varied according to different QRS configurations at baseline, the post-implant parameters showed no significant difference between groups. The association between repolarization parameters and LBBAP response was then evaluated among patients with wide QRS. Multivariate analysis demonstrated that post-implant TpTe was the independent predictor of LBBAP response (p < 0.05). Receiver operating characteristic analysis indicated an area under the curve of 0.77 (95% CI, 0.60-0.93) with a cutoff value of 81.2 ms (p < 0.01). Patients with post-implant TpTe<81.2 ms had a significantly higher rate of echocardiographic response (93.3 vs. 44.4%, p < 0.01). Further subgroup analysis indicated that the predictive value of post-implant TpTe for LBBAP response was more significant in non-left bundle branch block (LBBB) patients than in LBBB patients. Conclusion: LBBAP improved DVR significantly in HF patients. Post-implant TpTe was associated with the echocardiographic response after LBBAP among patients with wide QRS, especially for non-LBBB patients.

9.
Biomater Sci ; 10(19): 5583-5595, 2022 Sep 27.
Article in English | MEDLINE | ID: mdl-35975567

ABSTRACT

Periodontitis is a prevalent chronic inflammatory disease that destroys the periodontal supporting tissues, impinges on oral health, and is correlated with an increased risk of systemic disease. Currently, the main drug treatment is antibiotic therapy; however, systemic antibiotic therapy still has various drawbacks such as bacterial resistance, low bioavailability and burst release. It is noteworthy that the local use of non-antibiotic drugs with sustained release characteristics can effectively overcome these problems. It has been documented that chlorogenic acid (CGA) has good anti-inflammatory and antioxidant properties. To achieve the sustained release of CGA, we synthesized CGA-PLGA@PVP nanomicelles by loading CGA onto poly(D,L-lactide-co-glycolide) (PLGA) and modified them with polyvinylpyrrolidone (PVP) for better dispersion. The results demonstrated that CGA-PLGA@PVP nanomicelles could prolong the release time of CGA, and could not only effectively remove reactive oxygen species (ROS) but also downregulate the overexpression of proinflammatory cytokines in lipopolysaccharide (LPS)-treated RAW264.7 cells. Moreover, CGA-PLGA@PVP nanomicelles could remain in gingival tissue for more than 24 hours after local injection, inhibit alveolar bone resorption and prevent the progression of periodontitis in a mouse model, showing good biocompatibility. Therefore, CGA-PLGA@PVP nanomicelles have great properties and are expected to be a novel therapeutic strategy for periodontitis.


Subject(s)
Chlorogenic Acid , Periodontitis , Animals , Anti-Bacterial Agents/pharmacology , Antioxidants , Cytokines , Delayed-Action Preparations , Lipopolysaccharides , Mice , Periodontitis/drug therapy , Polylactic Acid-Polyglycolic Acid Copolymer , Povidone , Reactive Oxygen Species
10.
Article in English | MEDLINE | ID: mdl-35549025

ABSTRACT

Synchrotron X-rays are widely used for material characterizations. However, they can also ionize atoms and molecules to damage and manipulate probed materials. We report here an X-ray-induced growth of copper hydroxide nitrate, Cu2(OH)3NO3, on copper thin films in the ambient atmosphere without solvents and thermal treatment. In situ synchrotron X-ray diffraction measurements showed that the time-dependent growth process of theCu2(OH)3NO3 is accompanied by the consumption of Cu metal and can be described by a sigmoidal model. The growth rate was reduced after the initial fast growth period. Scanning electron microscopy (SEM) images show that the isolated islands of Cu2(OH)3NO3 nanoplates formed in the beginning, which grew together with new nanoplates formed under continued X-ray irradiation. The result demonstrated that high-flux synchrotron X-rays may provide an unconventional approach to synthesizing and manipulating materials, which will inspire future investigation both experimentally and theoretically.

11.
Small ; 18(26): e2202720, 2022 07.
Article in English | MEDLINE | ID: mdl-35637629

ABSTRACT

Nitrogen (N2 ) is an essential element for life, but kinetically stable N2 in the atmosphere needs to be reduced to biologically available forms as a nutrient for organisms. Abiotic nitrogen fixation is critical to the origin of life on the early Earth, which is due to lightning or mineral-based reduction. Here, synchrotron X-ray-induced silver nitrate formation on a silver copper (AgCu) thin-film is reported. Time-resolved X-ray diffraction measurements show that under intense X-ray exposure, initially formed silver oxides (AgOx) are quickly converted to silver nitrate (AgNO3 ). Interestingly, AgNO3 is first formed in its high-temperature phase with a space group of R3cH, which gradually transforms to the room temperature phase with a space group of Pbca under continuous X-ray irradiation. The result not only provides a new clue about the abiotic nitrogen reduction prior to life but also demonstrates a novel strategy of materials synthesis using synchrotron X-rays.


Subject(s)
Nitrogen , Synchrotrons , Atmosphere , Silver Nitrate , X-Rays
13.
Clin Res Cardiol ; 111(11): 1219-1230, 2022 Nov.
Article in English | MEDLINE | ID: mdl-34761309

ABSTRACT

BACKGROUND: Left bundle branch pacing (LBBP) is a novel near-physiological pacing method that still lacks quantitative criteria to guide the selection of lead-implanted sites to enhance the success likelihood of lead deployments. This study aimed to quantitatively analyze the relationships of LBBP success likelihood to the distribution of lead-implanted sites and the lead-localization-pacing electrocardiographic (ECG) features. METHODS: All the lead-implanted sites in patients with finally successful LBBP were enrolled for analysis, including successful and failed sites. A novel coordinate system was invented to describe the sites' distribution as longitudinal distance (longit-dist) and lateral distance (lat-dist). Corrected distance parameters were generated to eliminate the cardiac dimension variations. The lead-localization-pacing ECG parameters were also collected, such as paced QRS duration (locat-QRSd), left ventricular activation time (locat-LVAT), LVAT/QRSd ratio (locat-LVAT/QRSd), and QRS directions. RESULTS: A total of 94 patients with 105 successful sites and 93 failed sites were enrolled. Longit-dist and corrected longit-dist of successful sites were significantly longer, while locat-QRSd and locat-LVAT were shorter and locat-LVAT/QRSd was lower than failed sites. There was a positive dose-response relationship between LBBP success likelihood and corrected longit-dist with a cut-off of 26.95 mm, whereas there were negative dose-response relationships of LBBP success likelihood to locat-QRSd, locat-LVAT, and locat-LVAT/QRSd with the cut-offs of 142 ms, 92 ms, and 64.7%, respectively. Downward QRS direction in II/III ECG leads was also associated with successful LBBP. CONCLUSION: Longit-dist, locat-QRSd, locat-LVAT, and locat-LVAT/QRSd were quantitative parameters to guide the selection of lead-implanted sites during LBBP implantation. Quantitative distance and electrocardiographic parameters for lead-implanted site selection to enhance the success likelihood of left bundle branch pacing. LBBP, left bundle branch pacing; Longit-dist, longitudinal distance; CL-apex-dist, distance from contraction line to apex; LBBB, left bundle branch block; IVCD, intraventricular conduction delay; Locat-QRSd, lead-localization-pacing QRS duration; Locat-LVAT, lead-localization-pacing left ventricular activation time; Locat-LVAT/QRSd, lead-localization-pacing LVAT/QRSd ratio.


Subject(s)
Bundle of His , Cardiac Pacing, Artificial , Humans , Cardiac Pacing, Artificial/methods , Bundle-Branch Block/diagnosis , Bundle-Branch Block/therapy , Electrocardiography/methods , Heart Conduction System
14.
Heart Rhythm ; 18(6): 946-953, 2021 06.
Article in English | MEDLINE | ID: mdl-33781981

ABSTRACT

BACKGROUND: Left bundle branch pacing (LBBP) is an emerging physiological pacing modality. However, little is known about pacing at different locations on the left bundle branch (LBB). OBJECTIVE: The purpose of this study was to explore pacing and physiological characteristics associated with different LBBP locations. METHODS: The study included 68 consecutive patients with normal unpaced QRS duration and successful LBBP implantation. Patients were divided into 3 groups according to the paced QRS complex as left bundle branch trunk pacing (LBTP), left posterior fascicular pacing (LPFP), or left anterior fascicular pacing (LAFP). Electrocardiographic (ECG) characteristics, pacing parameters, and fluoroscopic localization were collected and analyzed. RESULTS: There were 17 (25.0%), 35 (51.5%), and 16 (23.5%) patients in the LBTP, LPFP, and LAFP groups, respectively. All subgroups had relatively narrow paced QRS complex (128.6 ± 9.1 ms vs 133.7 ± 11.2 ms vs 134.8 ± 9.6 ms; P = .170), fast left ventricular activation (70.4 ± 9.0 ms vs 70.6 ± 10.2 ms vs 71.0 ± 9.0 ms; P = .986), as well as low and stable pacing thresholds. Delayed right ventricular activation and interventricular dyssynchrony were similar between groups. Fluoroscopic imaging indicated that the lead tip was located most commonly in the basal-middle region of the septum (67.7%), and this was independent of paced QRS morphology group (88.2% vs 57.1% vs 68.8%; P = .106). CONCLUSION: Pacing at different sites of the LBB resulted in similar intraventricular and interventricular electrical synchrony in patients with an intact conduction system. Fluoroscopic imaging alone could not predict specific LBBP paced ECG morphology.


Subject(s)
Bundle of His/anatomy & histology , Bundle-Branch Block/diagnosis , Cardiac Pacing, Artificial/methods , Electrocardiography/methods , Fluoroscopy/methods , Heart Rate/physiology , Bundle of His/physiology , Bundle-Branch Block/physiopathology , Bundle-Branch Block/therapy , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Time Factors
15.
Behav Neurol ; 2020: 2097059, 2020.
Article in English | MEDLINE | ID: mdl-32509037

ABSTRACT

PRRT2 mutations are the major causative agent of paroxysmal kinesigenic dyskinesia with infantile convulsion (PKD/IC). The study is aimed at screening PRRT2 gene mutations in patients who suffered from PKD/IC in Chinese population. Thirteen Chinese patients with PKD/IC were screened randomly for coding exons of the PRRT2 gene mutation along with 50 ethnically coordinated control people. Nine (2 unaffected) and 4 of the patients showed familial PKD/IC and apparently sporadic cases, respectively. We identified 5 different PRRT2 mutations in 10 individuals, including 8 familial and 2 apparently sporadic cases. However, no mutations were found in the 50 ethnically matched controls. Unknown (novel) NM_145239.2:c.686G>A and previously reported NM_145239.2:c.743G>C variants were identified in two familial and sporadic patients. All affected members of family A showed mutation NM_145239.2:c.650_670delinsCAATGGTGCCACCACTGGGTTA. The previously identified NM_145239.2:c.412 C>G and NM_145239.2:c.709G>A variants are seen in two individuals assessed in family B. Other than the previously identified variants, some of the patients with PRRT2-PKD/IC showed a new PRRT2 substitution variant. Thus, the spectrum of PRRT2 variants is expanded. The possible role and probability of PRRT2 variants involved in PKD/IC are highlighted.


Subject(s)
Chorea , Dystonia , Epilepsy, Benign Neonatal , Membrane Proteins , Nerve Tissue Proteins , China , Dystonia/genetics , Female , Humans , Male , Membrane Proteins/genetics , Nerve Tissue Proteins/genetics , Seizures
16.
Adv Sci (Weinh) ; 6(16): 1900190, 2019 Aug 21.
Article in English | MEDLINE | ID: mdl-31453057

ABSTRACT

The interfacial decomposition products forming the so-called solid-electrolyte interphase (SEI) significantly determine the destiny of a Li-ion battery. Ultimate knowledge of its detailed behavior and better control are required for higher rates, longer life-time, and increased safety. Employing an electrochemical surface force apparatus, it is possible to control the growth and to investigate the mechanical properties of an SEI in a lithium-ion battery environment. This new approach is here introduced on a gold model system and reveals a compressible film at all stages of SEI growth. The demonstrated methodology provides a unique tool for analyzing electrochemical battery interfaces, in particular in view of alternative electrolyte formulations and artificial interfaces.

17.
Epilepsy Res ; 156: 106183, 2019 10.
Article in English | MEDLINE | ID: mdl-31404716

ABSTRACT

To investigate the neuroprotective effect of ferulic acid (FA) in a pentylenetetrazol (PTZ)-induced seizures model in rat, the motor response, spatial learning ability and memory capability of the rats were assessed. Both the antioxidation and anti-apoptosis pathways were also investigated. In this study, male Wistar rats were randomly divided into 3 groups (n = 12 in each group). For 28 days, the rats were administered saline alone (i.p. normal saline, NS group), PTZ (40 mg/kg, i.p., PTZ group) once daily to induce seizures, or FA (i.p. 60 mg/kg) 20 min before being given PTZ (40 mg/kg, i.p., FA + PTZ group) to assess the neuroprotective effect of FA. The motor response of the rats was analysed with the Racine scale. The spatial learning and memory capacity of the rats were assessed by the Morris water maze test. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured, and both in situ staining with the DNA-binding bisbenzimide Hoechst 33258 and TUNEL assays were used to assess apoptosis. Western blotting was used to further analyse the expression of Apaf-1, caspase-9, caspase-3, Bcl-2, Bid, Bax, cleaved caspase-3 and cytochrome c. The results showed that compared to the those of the PTZ group, FA pre-treatment significantly (p < 0.01) reduced the Racine scores starting at day 4, prolonged the latency of the onset of seizure at day 28, reduced the escape latency period starting at day 2, increased the frequency of crossing the platform location, increased the SOD activity, reduced the MDA content and apoptosis percentage, and upregulated the Bcl-2 levels whilst downregulating the Bax, cytochrome c, Apaf-1, caspase-9, caspase-3, cleaved caspase-3 and Bid expression levels. This study demonstrated that pre-treatment with FA exerts strong neuroprotective effects by reducing the motor response and by improving spatial learning ability and memory capacity. The neuroprotective effect may be a result of a reduction in neuron cell death that occurs via the antioxidative and anti-apoptotic pathways.


Subject(s)
Antioxidants/pharmacology , Convulsants/pharmacology , Neurons/drug effects , Pentylenetetrazole/pharmacology , Seizures/drug therapy , Animals , Apoptosis/drug effects , Coumaric Acids , Malondialdehyde/metabolism , Malondialdehyde/pharmacology , Memory/drug effects , Neurons/pathology , Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Rats, Wistar , Seizures/chemically induced , Seizures/metabolism
18.
Front Microbiol ; 9: 2069, 2018.
Article in English | MEDLINE | ID: mdl-30233542

ABSTRACT

Both high- and low-pathogenic H7N9 influenza A virus (IAV) infections have been found in human and poultry in China, and most human cases are related to contact with infected poultry. It is necessary to develop a rapid and simple method to detect H7N9 IAV in poultry. In this study, 13 monoclonal antibodies (McAbs) against the H7N9 IAV hemagglutinin were developed, and three critical amino acid epitopes (198, 227, 235) were identified based on the reactivity of these variant and wild-type strains with the McAbs. We developed an immunochromatographic assay for H7N9 AIVs using two McAbs recognizing the epitope position 227 and 235. The assay had good specificity, stability, and sensitivity, with a detection limit of swab and tissue samples of 2.5 log10EID50/0.1 mL, which is suitable for the analysis of clinical samples. This assay provides an effective method for the rapid detection of H7N9 AIVs in poultry.

19.
Chemphyschem ; 18(21): 3056-3065, 2017 Nov 03.
Article in English | MEDLINE | ID: mdl-28872763

ABSTRACT

The molecular structure at charged solid/liquid interfaces is vital for many chemical or electrochemical processes, such as adhesion, catalysis, or the stability of colloidal dispersions. How cations influence structural hydration forces and interactions across negatively charged surfaces has been studied in great detail. However, how anions influence structural hydration forces on positively charged surfaces is much less understood. Herein we report force versus distance profiles on freshly cleaved mica using atomic force microscopy with silicon tips. We characterize steric anion hydration forces for a set of common anions (Cl- , ClO4- , NO3- , SO42- and PO43- ) in pure acids at pH ≈1, where protons are the co-ions. Solutions containing anions with low hydration energies exhibit repulsive structural hydration forces, indicating significant ion and/or water structuring within the first 1-2 nm on a positively charged surface. We attribute this to specific adsorption effects within the Stern layer. In contrast, ions with high hydration energies show exponentially repulsive hydration forces, indicating a lower degree of structuring within the Stern layer. The presented data demonstrates that anion hydration forces in the inner double layer are comparable to cation hydration forces, and that they qualitatively correlate with hydration free energies. This work contributes to understanding interaction processes in which positive charge is screened by anions within an electrolyte.

20.
Inorg Chem ; 56(17): 10204-10214, 2017 Sep 05.
Article in English | MEDLINE | ID: mdl-28805370

ABSTRACT

An m-phthalic diamide-linked bisporphyrin with a benzylamide substituent has been designed and synthesized. It has two types of carbonyl groups. In the solution of this zinc bisporphyrinate, these carbonyl groups are involved in the formation of two different Zn-O coordination interactions: one is formed between neighboring zinc bisporphyrinates; another is formed within zinc bisporphyrinate. The chirality sensing abilities of this zinc porphyrinate to a number of chiral monoamines have been examined. When zinc bisporphyrinate was mixed with a series of chiral monoamines, the signs of the circular dichroism spectra for the chiral monoamines of the same handedness with an aryl group as the substituent are just opposite to those with an alkyl group as the substituent. NMR studies reveal that stepwise coordinations lead to 1:1 and 1:2 host-guest complexes. The structure of the 1:1 host-guest complex was confirmed by crystallography, it is the first time that a 1:1 host-guest complex formed between zinc bisporphyrinate and a chiral monoamine has been crystallographically characterized. The structure reveals that there is an intramolecular hydrogen bond between the amide oxygen and the coordinated NH2. We further investigated the chirality transfer mechanism by density functional theory calculations. Our studies suggest that the interactions between the linker and guests in this bisporphyrin system are crucial in the chirality transfer process, and the nature of the bulkiest substituent of chiral monoamines makes a difference. For R-type guests, with an alkyl group, the steric repulsion makes the conformer A more energetically favorable, which leads to the anticlockwise twist and negative Cotton effect. However, with an aryl group, the π-π interaction makes the conformer B more energetically favorable, which leads to the clockwise twist and positive Cotton effect.

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