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1.
ACS Nano ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32195582

##### RESUMO

Microscale intelligent actuators capable of sensitive and accurate manipulation under external stimuli hold great promise in various fields including precision sensors and biomedical devices. Current microactuators, however, are often limited to a multiple-step fabrication process and multimaterials. Here, a pH-triggered soft microactuator (<100 µm) with simple structure, one-step fabrication process, and single material is proposed, which is composed of deformable hydrogel microstructures fabricated by an asymmetric femtosecond Bessel beam. To further explore the swelling-shrinking mechanism, the hydrogel porosity difference between expansion and contraction states is investigated. In addition, by introducing the dynamic holographic processing and splicing processing method, more complex responsive microstructures (S-shaped, C-shaped, and tortile chiral structures) are rapidly fabricated, which exhibit tremendous expected deformation characteristics. Finally, as a proof of concept, a pH-responsive microgripper is fabricated for in situ capturing polystyrene (PS) particles and neural stem cells rapidly. This flexible, designable, and one-step approach manufacturing of intelligent actuator provides a versatile platform for micro-objects manipulation and drug delivery.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32208611

##### RESUMO

Manipulating gas bubbles in aqueous ambient is of great importance for applications in water treatment, gas collection and matter transport. Here, a kind of Janus foam is designed and fabricated by one-step ultrafast laser ablation of one side of cooper film, which is treated to be superhydrophobic. The Janus foam exhibits not only the capability of unidirectional transport of underwater bubbles, but also gas collection with favorable efficiency up to ~15 mL cm-2 min-1. The underlying physical mechanism is attributed to the cooperation of the buoyancy, adhesion and wetting gradient forces imposed on the bubbles. As a paradigm, the underwater chemical reaction between unidirectional CO2 gas flow and alkaline phenolphthalein solution is demonstrated via the Janus foam. This facile and low-cost fabrication approach for Janus foam will find broad potential applications for effective bubble transport, carbon capture and controllable chemical reactions in aqueous conditions.

3.
J Med Virol ; 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32181911

##### RESUMO

4.
J Nat Prod ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32130008

##### RESUMO

Fumiquinazoline alkaloids have attracted much attention from medicinal and natural product chemists due to their interesting structures and biological potential. In this study, three new and 12 known fumiquinazoline alkaloids were isolated and characterized from the marine fungus Scedosporium apiospermum F41-1. The structures of the new compounds and their absolute configurations were determined using NMR spectroscopy, ECD, and OR calculations. The compounds were evaluated for their antidiabetic potential by determining their triglyceride-promoting activity using 3T3-L1 adipocytes. One of the new compounds, scequinadoline J (14), as well as scequinadolines D (9) and E (10), was found to promote triglyceride accumulation in 3T3-L1 cells. Scequinadoline D (9) demonstrated the most potent activity, with an EC50 value of 0.27 ± 0.03 µM. Quantitative polymerase chain reaction experiments suggested that scequinadoline D (9) acts through activation of the PPARÎ³ pathway. It stimulated the mRNA expression of PPARÎ³, AMPKα, C/EBPα, LXRα, SCD-1, and FABP4. In addition, its triglyceride-promoting efficacy could be blocked by a double dose of the PPARÎ³ antagonist GW9662. These results indicated that scequinadoline D (9) is a potent insulin sensitizer that targets adipocytes and may be useful for the treatment of type 2 diabetes mellitus after further investigation.

5.
Anal Chim Acta ; 1105: 112-119, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32138909

##### RESUMO

Perturbation of thiol homeostasis in biological fluids are thought to be associated with several diseases, and reliable analytical methods for the determination of low molecular weight (LMW) thiols in human plasma or serum are thus required. In this study, a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method is described for high throughput determination of four LMW thiols (glutathione, cysteine, homocysteine and cysteinylglycine) in human serum. It is based on the use of a bromoacetyl functionalized C60 (Br-C60) as a derivatization reagent to label thiols. The Br-C60 labeling can add an 832-Da tag to thiols, which moves thiol signals to high mass region and effectively avoids the signal interference generated by the traditional MALDI matrix below 800 Da. The labeling can be completed within 5 min under microwave-assisted condition. Thereby, the Br-C60 labeling based MALDI-TOF MS analytical method can achieve high throughput analysis of LMW thiols in serum. Good linearities of the method for the thiols in human serum were obtained in the range of 0.5-500.0 µM with correlation coefficient (R) greater than 0.9960. The limit of detection is in the range of 0.07-0.18 µM for the investigated thiols in human serum with relative standard deviations of lower than 13.5% and recoveries ranging from 81.9 to 117.1%. Using the method, four thiols in microliter serum samples of breast cancer (BC) patients were determined. The result showed that the contents of the four thiols in BC serum samples significantly changed compared to the healthy control (HC).

6.
Artigo em Inglês | MEDLINE | ID: mdl-32119514

##### RESUMO

Ultra-broadband photodetection is crucial for various applications like imaging and sensing and has become a hot research topic in recent years. However, most of the reported ultra-broadband photodetectors can only cover the range from ultraviolet to infrared, which is insufficient. Herein, a photothermoelectric (PTE) detector made of NbS3 is reported. The device shows a considerable performance from ultraviolet to terahertz. For all examined wavelengths, the photoresponsivities are all larger than 1 V W-1 while the response time is less than 10 ms, much shorter than the reported ultra-broadband photodetectors made of millimetric scale graphene, ternary chalcogenide single crystal, and other materials. The extraordinary performance is fully discussed and can be attributed to the thermal localization enhanced PTE effect. Because of the short thermal decay length and low thermal loss, the heat generated by the illumination is localized in only a micrometer scale along the channel, and thus a strong PTE response is produced. In addition, the fabricated device also demonstrates robust flexibility and stability. Thanks to the quasi-one-dimensional (quasi-1D) structure, the NbS3 crystal is easy to be scaled down and thus intrinsically facilitate the integration of detectors. With these favorable merits, the quasi-1D NbS3 crystal holds a promising potential in high-performance, ultra-broadband photodetectors.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32164877

##### RESUMO

8.
Mil Med Res ; 7(1): 4, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029004

##### RESUMO

In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province; and then named "2019 novel coronavirus (2019-nCoV)" by the World Health Organization (WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world's attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development; we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control (including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.

##### Assuntos
Betacoronavirus , Infecções por Coronavirus , Infecção Hospitalar , Controle de Infecções , Programas de Rastreamento , Equipamento de Proteção Individual , Pneumonia Viral , Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , Betacoronavirus/patogenicidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Infecção Hospitalar/prevenção & controle , Diagnóstico Diferencial , Medicamentos de Ervas Chinesas , Medicina Baseada em Evidências , Hidratação , Humanos , Controle de Infecções/normas , Pulmão/diagnóstico por imagem , Epidemiologia Molecular , Cuidados de Enfermagem , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/etiologia , Pneumonia Viral/terapia , Pneumonia Viral/transmissão
9.
Opt Lett ; 45(5): 1071-1074, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32108772

##### RESUMO

In this Letter, we propose a new (to the best of our knowledge), promising concept of a hybrid femtosecond (fs) laser processing method composed of single-point scanning and holographic light modulation fabrication for manufacturing a tunable-size microtrap chip. The hybrid method not only ensures key microfluidic device precision but also greatly improves the fabrication speed. By using a new asymmetry-bracket-shaped microtrap design with a mechanical strain stretching method, real-time size-tunable trapping is obtained, and a 100% particle trapping retention is realized, ignoring the flow fluctuation. Finally, the microtrap array is successfully applied to trap single yeast cells and hold them for $\sim{10}\;{\rm h}$â¼10h without escaping.

10.
BMC Biol ; 18(1): 13, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050971

##### RESUMO

BACKGROUND: Hybridisation and introgression play key roles in the evolutionary history of animal species. They are commonly observed within several orders in wild birds. The domestic chicken Gallus gallus domesticus is the most common livestock species. More than 65 billion chickens are raised annually to produce meat and 80 million metric tons of egg for global human consumption by the commercial sector. Unravelling the origin of its genetic diversity has major application for sustainable breeding improvement programmes. RESULTS: In this study, we report genome-wide analyses for signatures of introgression between indigenous domestic village chicken and the four wild Gallus species. We first assess the genome-wide phylogeny and divergence time across the genus Gallus. Genome-wide sequence divergence analysis supports a sister relationship between the Grey junglefowl G. sonneratii and Ceylon junglefowl G. lafayettii. Both species form a clade that is sister to the Red junglefowl G. gallus, with the Green junglefowl G. varius the most ancient lineage within the genus. We reveal extensive bidirectional introgression between the Grey junglefowl and the domestic chicken and to a much lesser extent with the Ceylon junglefowl. We identify a single case of Green junglefowl introgression. These introgressed regions include genes with biological functions related to development and immune system. CONCLUSIONS: Our study shows that while the Red junglefowl is the main ancestral species, introgressive hybridisation episodes have impacted the genome and contributed to the diversity of the domestic chicken, although likely at different levels across its geographic range.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32100537

##### RESUMO

Shape memory polymer (SMP) surfaces with tunable wettability have attracted extensive attention due to their widespread applications. However, there have been rare reports on in situ tuning wettability with SMP materials. In this paper, we reported a kind of distinct superhydrophobic SMP microconed surface on the silver nanowire (AgNW) film to achieve in situ reversible transition between pinned and roll-down states. The mechanism is taking advantage of the in situ heating functionality of the silver nanowire film by voltage, which provides the transition energy for SMP to achieve the fixation and recovery of temporary shape. It is noteworthy that the reversible transition could be repeated many times (>100 cycles), and we quantitatively investigate the shape memory ability of microcones with varied height and space under different applied voltages. These results show that the tilted microcones could recover its original upright state under a small voltage (4-11 V) in a short time, and the shortest recovery time is about 0.5 min under an applied voltage of â¼10 V. Finally, we utilize SMP microcone arrays with tunable wettability to realize lossless droplet transportation, and the tilted microconed surface also achieves liquid unidirectional transport due to its anisotropic water adhesion force. The robust microconed SMP surface with reversible morphology transitions will have far-ranging applications including droplet manipulation, reprogrammable fog harvesting, and so on.

12.
J Viral Hepat ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32048386

##### RESUMO

Not all treatment-naïve patients receiving entecavir (ETV) or tenofovir disoproxil fumarate (TDF) therapy can achieve complete virological response, and many factors may be related with the outcome of partial virological response. This study aimed to determine whether the manner of drug administration affects the antiviral efficacy of ETV/TDF monotherapy. All eligible patients were divided into complete or partial response cohorts based on their virological response following 24-week therapy. Factors related with partial response were evaluated. Patients with partial response were further grouped depending on whether they later adjusted the manner of drug administration, and the antiviral efficacy was compared between the two groups during prolonged treatment. A total of 518 patients were enrolled. Suboptimal drug administration (OR 77.511, P = .000), positive-HBeAg (OR 3.191, P = .000) and ETV treatment (OR 2.537, P = .001) were identified as independent risk factors for partial response. Among patients with partial response, 213 were in the adjusted group and 76 were in the unadjusted group. The percentages of patients with undetectable serum HBV DNA (78.9% vs 31.6%, P < .001) and with normal alanine aminotransferase (ALT) (88.7% vs 68.4%, P < .001) were both higher in the adjusted group than that in unadjusted group following a further 6-month therapy. In conclusion, the manner of drug administration is an important factor influencing the efficacy of ETV/TDF therapy, and optimal drug administration manner can help to increase antiviral efficacy and rescue patients with partial response.

13.
Genome Biol ; 21(1): 46, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093779

##### RESUMO

Following publication of the original paper [1], the authors reported an error in the affiliation of Xin-Tian Hu, who is also affiliated with "Kunming Primate Research Center, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China".

14.
Dalton Trans ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32067026

##### RESUMO

A family of new dinuclear lanthanide complexes as the simplest entities showing intramolecular magnetic interactions, [Ln2(dbm)2(L)2(CH3OH)2] (Ln = Tb (1), Dy (2), Ho (3), Er (4), Yb (5), Lu (6)), [Ln2(acac)2(L)2(EtOH)2] (Ln = Dy (7), Er (8)), [Dy2(TTA)2(L)2(CH3OH)2]·2CH2Cl2 (9) and [Dy2(tfa)2(L)2(CH3OH)2] (10) (H2L = N'-(2-hydroxy-5-methylphenyl)-pyrazine-2-carbohydrazide, Hdbm = 1,3-diphenyl-1,3-propanedione, Hacac = acetylacetone, HTTA = 2-thenoyltrifluoroacetone, Htfa = trifluoroacetylacetone), were constructed successfully by the reaction of a Schiff base ligand H2L and four different ß-diketonate salts. As for complexes 4, 5 and 8, all exhibit the characteristic emission peaks of the corresponding Er3+, Yb3+ and Er3+ ions, respectively. Meanwhile, the excitation wavelength (510 nm) of 5 is located in the visible region, confirming its significant potential application value. Magnetic studies indicate that complexes 9 and 10 exhibit characteristic slow relaxation of magnetization with the energy barriers (Ueff) of 102 K for 9 and 140 K for 10 under a zero dc field. Under the optimized dc fields, slow magnetic relaxations are present in 2 and 7, and the Ueff values of 9 and 10 have been improved. This proves that the ß-diketonate co-ligands deserve an important role in regulating Dy-SMMs influenced by the diverse perturbations of the axial crystal field originating from minor changes in the coordination environment.

15.
Dig Dis Sci ; 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32076933

##### RESUMO

BACKGROUND: Acute pancreatitis (AP) has a wide spectrum of severity and can be associated with considerable morbidity and mortality. Whether gut microbiota dysbiosis is associated with AP severity remains obscure. AIMS: We aim to investigate the differences in the alterations of gut microbiota in different grades of AP severity. METHODS: We collected clinical information and rectal swab samples from 80 individuals. The gut microbiota was tested by 16S rRNA gene sequencing, gut microbiota species composition analysis, difference analysis, random forest model prediction analysis, and gut microbiota species correlation network analysis. RESULTS: There was a different microbiota profile in different severity grades. Bacteroides, Escherichis-Shigella, and Enterococcus were dominant species in mild, moderately severe, and severe AP, respectively. Finegoldia was the most significantly increased and Blautia the most decreased species in mild AP. Anaerococcus was the most significantly increased and Eubacterium hallii the most decreased species in moderately severe AP. Enterococcus was the most significantly increased and Eubacterium hallii the most decreased species in severe AP. Finegoldia, Eubacterium_hallii, and Lachnospiraceae were potential diagnostic biomarkers for mild AP and Eubacterium_hallii and Anaerococcus for moderately severe AP. There was a positive interaction between Firmicutes and Bacteroidetes in mild AP. CONCLUSIONS: The disturbed gut microbiota is different among grades of AP, suggesting their potential role in the progression of disease severity. There was a different microbiota profile in different severity grades. Bacteroides, Escherichis-Shigella, and Enterococcus were dominant gut microbiota species in MAP, MSAP, and SAP, respectively. Finegoldia was the most significantly increased and Blautia the most decreased gut microbiota species in MAP. Anaerococcus was the most significantly increased and Eubacterium hallii the most decreased species in MSAP. Enterococcus was the most significantly increased and Eubacterium hallii the most decreased species in SAP. Finegoldia, Eubacterium_hallii, and Lachnospiraceae were potential diagnostic biomarkers for MAP and Eubacterium_hallii and Anaerococcus for MSAP. There was a positive interaction between Firmicutes and Bacteroidetes in MAP.

16.
Mol Biol Evol ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32077944

##### RESUMO

The transition of terrestrial snakes to marine life approximately 10 million years ago (Ma) is ideal for exploring adaptive evolution. Sea snakes possess phenotype specializations including laterally compressed bodies, paddle-shaped tails, valvular nostrils, cutaneous respiration, elongated lungs and salt glands yet knowledge on the genetic underpinnings of the transition remain limited. Herein, we report the first genome of Shaw's sea snake (Hydrophis curtus) and use it to investigate sea snake secondary marine adaptation. A hybrid assembly strategy obtains a high quality genome. Gene family analyses date a pulsed coding-gene expansion to about 20 Ma, and these genes associate strongly with adaptations to marine environments. Analyses of selection pressure and convergent evolution discover the rapid evolution of protein-coding genes, and some convergent features. Additionally, 108 conserved non-coding elements appear to have evolved quickly, and these may underpin the phenotypic changes. Transposon elements may contribute to adaptive specializations by inserting into genomic regions around functionally related coding genes. The integration of genomic and transcriptomic analyses indicates independent origins and different components in sea snake and terrestrial snake venom; the venom gland of the sea snake harbours the highest PLA2 (17.23%) expression in selected elapids and these genes may organize tandemly in the genome. These analyses provide insights into the genetic mechanisms that underlay the secondary adaptation to marine and venom production of this sea snake.

17.
Opt Lett ; 45(4): 897-900, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058499

##### RESUMO

In this Letter, we demonstrate a laser fabrication strategy that uses the long focal depth femtosecond axilens laser beam to manufacture the high-aspect-ratio (HAR) micropillars and atomic force microscopy (AFM) probes by one-step exposure. The long depth of focus is generated by modulating laser beam focused at different positions. By adjusting the exposure height, the morphology of HAR micropillars can be tuned flexibly, and the micropillar with an ultra-high aspect ratio (diameter of 1.5 µm, height of 102 µm, ${\rm AR}={70}$AR=70) can be fabricated within 10 ms which is a great challenge for other processing methods to obtain such a HAR microstructure in such a short time. In addition, the HAR micropillar is fabricated onto a cantilever to form the AFM probe. The homemade probe shows fine imaging quality. This method greatly improves the processing efficiency while ensuring the fabrication resolution which provides a powerful method for processing HAR microstructures.

18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(2): 145-150, 2020 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-32030942

##### RESUMO

Objective: To summarize the clinical application and research progress in unicompartmental knee arthroplasty (UKA). Methods: The literature related to UKA in recent years was reviewed and the emerging indications, implant options, comparisons between other surgical techniques, and recent advances were summarized. Results: Clinical studies show that UKA has many advantages, such as less trauma, faster recovery, and fewer postoperative complications. At present, the operative indication has been expanded. The body mass index more than 25 kg/m 2, less than 60 years old, patellofemoral arthritis, and anterior cruciate ligament dysfunction are no longer considered as contraindications. The prosthesis type in UKA should be selected according to the patient's condition. In recent years, the robot-assisted UKA can effectively improve the effectiveness, improve patient satisfaction, and reduce postoperative complications. Conclusion: With the development of surgical techniques, designs of prosthesis, and the robotic technology, UKA would be further applicated. As more long-term data on UKA become available, it will further guide clinicians in counseling patients on whether UKA should be performed.

##### Assuntos
Artroplastia do Joelho , Prótese do Joelho , Humanos , Articulação do Joelho , Pessoa de Meia-Idade , Osteoartrite do Joelho , Satisfação do Paciente , Complicações Pós-Operatórias , Resultado do Tratamento
19.
Med Sci Monit ; 26: e919530, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31901930

##### RESUMO

BACKGROUND The aim of this study was to investigate the clinical significance of NLRP3 and HMGB1 in patients with active ulcerative colitis. MATERIAL AND METHODS This was a prospective observational study which included a total of 62 cases with active ulcerative colitis during January 2017 to December 2018. The patients were divided into a mild/moderate group or a severe group according to Sutherland Disease Activity Index (DAI) score. Clinical activity index and endoscopic index were used to determine the severity of UC. Serum levels of NLRP3, HMGB1, endothelin-1, IL-1ß, and TNF-alpha were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS Sutherland DAI score, clinical activity index, and endoscopic index were all significantly higher in severe patients than in the mild/moderate group. NLRP3, HMGB1, endothelin-1, IL-1ß, and TNF-alpha were significantly higher in severe UC patients. NLRP3 level was positively correlated with HMGB1, ET-1, IL-1ß, and TNF-alpha levels. Both NLRP3 and HMGB1 were positively correlated with Sutherland DAI score, clinical activity index, and endoscopic index. CONCLUSIONS Both serum NLRP3 and HMGB1 were elevated in UC patients, and the serum levels of NLRP3 were positively correlated with serum levels of HMGB1, ET-1, IL-1ß, and TNF-alpha, as well as severity of UC patients.

20.
Sci Rep ; 10(1): 826, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31964915

##### RESUMO

MDS development is a dynamic process during which the accumulation of somatic mutations leads to specific malignant evolution. To elucidate the differential roles of gene mutations in typical MDS, we used targeted sequencing to investigate clonal patterns from 563 patients and focused on cases (199/563 cases) with initial mutations (ASXL1, DNMT3A and TET2) at MDS diagnosis. The consistency of frequency and distribution in patients with or without aberrant chromosomes suggested early events of these initial mutations. Some additional driver mutations (SF3B1, U2AF1 or RUNX1) played roles to keep the basic disease features, or give rise to different phenotypes (BCOR, EZH2 or TP53) in individual patients. Notably, analysis in paired samples before and after MDS progression showed that the mutations identified as last events (involving active signaling, myeloid transcription or tumor suppressor) seemed necessary for MDS development to be AML. Last mutations can exist at MDS diagnosis, or emerge at AML transformation, and involve a small group of genes. Single-allele CEBPA mutations and diverse TP53 mutations were checked as the most common last event mutations. Considering the necessity of last event mutations and limited gene involvement in AML transformations, it is possible to validate a small group of last events involved mutations to develop some new strategies to block MDS progression.