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1.
Proc Natl Acad Sci U S A ; 121(3): e2308994121, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38190536

RESUMEN

The relationship between initial Homo sapiens dispersal from Africa to East Asia and the orbitally paced evolution of the Asian summer monsoon (ASM)-currently the largest monsoon system-remains underexplored due to lack of coordinated synthesis of both Asian paleoanthropological and paleoclimatic data. Here, we investigate orbital-scale ASM dynamics during the last 280 thousand years (kyr) and their likely influences on early H. sapiens dispersal to East Asia, through a unique integration of i) new centennial-resolution ASM records from the Chinese Loess Plateau, ii) model-based East Asian hydroclimatic reconstructions, iii) paleoanthropological data compilations, and iv) global H. sapiens habitat suitability simulations. Our combined proxy- and model-based reconstructions suggest that ASM precipitation responded to a combination of Northern Hemisphere ice volume, greenhouse gas, and regional summer insolation forcing, with cooccurring primary orbital cycles of ~100-kyr, 41-kyr, and ~20-kyr. Between ~125 and 70 kyr ago, summer monsoon rains and temperatures increased in vast areas across Asia. This episode coincides with the earliest H. sapiens fossil occurrence at multiple localities in East Asia. Following the transcontinental increase in simulated habitat suitability, we suggest that ASM strengthening together with Southeast African climate deterioration may have promoted the initial H. sapiens dispersal from their African homeland to remote East Asia during the last interglacial.


Asunto(s)
Pueblo Asiatico , Migración Humana , Tiempo (Meteorología) , Humanos , África , Asia , Asia Oriental
2.
Nano Lett ; 24(10): 3196-3203, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38437624

RESUMEN

Gelation is a promising method to assemble 3D macroscopic structures from MXene sheets for various applications. However, the fine control and scalable manufacturing of 3D MXene monoliths remains a great challenge. Herein, the controllable gelation of Ti3C2Tx MXene initiated by various ionic liquids (ILs) is first proposed, where the IL serve as linkers to bond the nanosheets together through electrostatic and hydrogen bonding interactions, forming 3D monoliths with well-adjustable structure. Furthermore, density functional theory calculations and experiments further reveal the cross-linking effect of different ILs. Typically, 3D porous structure with high specific surface area, suitable pore size, and improved electrolyte affinity is designed through the cross-linking of Ti3C2Tx with 1-vinyl-3-ethylimidazole bromide ([C2VIm]Br-Ti3C2Tx). Due to the strong coupling, the as-synthesized monolith possesses excellent rate performance and high energy density. The methodology is quite flexible, controllable, and universal that provides a new perspective for promoting innovative applications of 2D materials.

3.
J Am Chem Soc ; 146(8): 5355-5365, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38358943

RESUMEN

The twin boundary, a common lattice plane of mirror-symmetric crystals, may have high reactivity due to special atomic coordination. However, twinning platinum and iridium nanocatalysts are grand challenges due to the high stacking fault energies that are nearly 1 order of magnitude larger than those of easy-twinning gold and silver. Here, we demonstrate that Turing structuring, realized by selective etching of superthin metal film, provides 14.3 and 18.9 times increases in twin-boundary densities for platinum and iridium nanonets, comparable to the highly twinned silver nanocatalysts. The Turing configurations with abundant low-coordination atoms contribute to the formation of nanotwins and create a large active surface area. Theoretical calculations reveal that the specific atom arrangement on the twin boundary changes the electronic structure and reduces the energy barrier of water dissociation. The optimal Turing-type platinum nanonets demonstrated excellent hydrogen-evolution-reaction performance with a 25.6 mV overpotential at 10.0 mA·cm-2 and a 14.8-fold increase in mass activity. And the bifunctional Turing iridium catalysts integrated in the water electrolyzer had a mass activity 23.0 times that of commercial iridium catalysts. This work opens a new avenue for nanocrystal twinning as a facile paradigm for designing high-performance nanocatalysts.

4.
Hepatology ; 77(2): 456-465, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35714036

RESUMEN

BACKGROUND AND AIMS: A better understanding of the underlying mechanism of acetaminophen (APAP)-induced liver injury (AILI) remains an important endeavor to develop therapeutic approaches. Eosinophils have been detected in liver biopsies of patients with APAP overdose. We recently demonstrated a profound protective role of eosinophils against AILI; however, the molecular mechanism had not been elucidated. APPROACH AND RESULTS: In agreement with our previous data from experiments using genetic deletion of eosinophils, we found that depletion of eosinophils in wild-type (WT) mice by an anti-IL-15 antibody resulted in exacerbated AILI. Moreover, adoptive transfer of eosinophils significantly reduced liver injury and mortality rate in WT mice. Mechanistic studies using eosinophil-specific IL-4/IL-13 knockout mice demonstrated that these cytokines, through inhibiting interferon-γ, mediated the hepatoprotective function of eosinophils. Reverse phase protein array analyses and in vitro experiments using various inhibitors demonstrated that IL-33 stimulation of eosinophils activated p38 mitogen-activated protein kinase (MAPK), and in turn, cyclooxygenases (COX), which triggered NF-κB-mediated IL-4/IL-13 production. In vivo adoptive transfer experiments showed that in contrast to naive eosinophils, those pretreated with COX inhibitors failed to attenuate AILI. CONCLUSIONS: The current study revealed that eosinophil-derived IL-4/IL-13 accounted for the hepatoprotective effect of eosinophils during AILI. The data demonstrated that the p38 MAPK/COX/NF-κB signaling cascade played a critical role in inducing IL-4/IL-13 production by eosinophils in response to IL-33.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Enfermedad Hepática Inducida por Sustancias y Drogas , Animales , Ratones , Acetaminofén/efectos adversos , Eosinófilos , Interleucina-4/metabolismo , Interleucina-4/farmacología , Interleucina-13/metabolismo , Interleucina-13/farmacología , Interleucina-33/metabolismo , Interleucina-33/farmacología , FN-kappa B/metabolismo , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/patología , Hígado/patología , Ciclooxigenasa 2 , Ratones Noqueados , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Ratones Endogámicos C57BL
5.
Eur Arch Otorhinolaryngol ; 281(7): 3707-3715, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38671169

RESUMEN

PURPOSE: To evaluate the clinical implication of magnetic resonance imaging (MRI)-derived skeletal muscle index (SMI) in locoregionally advanced nasopharyngeal carcinoma (LANPC) patients undergoing induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT) and further to develop a nomogram for predicting survival prognosis. METHODS: SMI was determined through baseline MRI at the third cervical level. The nomogram was based on a training cohort involving 409 LANPC patients. We validated the prognostic accuracy of this prognostic model in an internal validation cohort (n = 204) and an external independent cohort (n = 272). RESULTS: SMI was an independent risk factor for OS. A prognostic model comprising age, TNM stage and SMI for individual survival prediction was developed and graphically represented as a nomogram. The model showed favorable discrimination (C-index: 0.686), predictive accuracy [time dependent area under the curve (tAUC) at 5 years: 0.70], and calibration, and was further validated in the internal and external validation datasets. A risk stratification derived from the model stratified these patients into three prognostic subgroups with significantly different survival. CONCLUSIONS: Low SMI accessed by MRI was significantly associated with poor overall survival in LANPC patients undergoing IC + CCRT. Moreover, we established and validated a novel nomogram involving age, TNM stage and SMI that could provide accurate prognostic stratification among this population.


Asunto(s)
Imagen por Resonancia Magnética , Músculo Esquelético , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Estadificación de Neoplasias , Nomogramas , Humanos , Masculino , Imagen por Resonancia Magnética/métodos , Femenino , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/mortalidad , Persona de Mediana Edad , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/terapia , Adulto , Pronóstico , Músculo Esquelético/patología , Músculo Esquelético/diagnóstico por imagen , Quimioradioterapia , Anciano , Quimioterapia de Inducción , Estudios Retrospectivos , Factores de Riesgo
6.
Br J Haematol ; 202(3): 623-635, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36951360

RESUMEN

Hereditary factor VII (FVII) deficiency is a rare recessive bleeding disorder with an estimated prevalence of 1/500 000. We had investigated 50 unrelated Chinese patients with FVII deficiency and identified, in total, 25 mutations, including 18 missense mutations and 5 splicing mutations, on the F7 gene. The nucleotide transition c.1224T>G (p.His408Gln) in exon 9 constitutes a hotspot of mutation, with 19 patients harbouring this genetic variance. Few patients were homozygous or compound heterozygous for deleterious mutations, such as non-sense mutations, large insertion or deletions, indicating that complete deficiency of FVII may not be compatible with life. The eight novel mutations identified in the study, including one small deletion (p.Glu49GlyfsTer101), three type I missense mutations, p.Cys238Phe, p.Gly420Asp, p.Ala252Val and four type II missense mutations, p.Val336Met, p.Ser342Gly, p.Gly432Ser and p.Ile213Asn, were further analysed by in vitro expression and functional studies. The laboratory phenotype and structural analysis confirmed the functional consequence of p.Ile213Asn mutation involving cleavage and activation site. The molecular dynamic simulations and binding energy calculations along with functional probing of p.Gly432Ser mutation revealed the critical role of residue Gly432 in the binding between activated factor VII (factor VIIa) and tissue factor.


Asunto(s)
Pueblos del Este de Asia , Deficiencia del Factor VII , Factor VII , Humanos , Pueblos del Este de Asia/genética , Factor VII/genética , Deficiencia del Factor VII/etnología , Deficiencia del Factor VII/genética , Factor VIIa , Genotipo , Mutación
7.
Arch Biochem Biophys ; 747: 109767, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37748625

RESUMEN

Pathological platelet activation plays a vital role in the prevalence of cardiovascular diseases. Hydroxysafflor yellow A (HSYA) has been shown to have significant anti-platelet aggregation and anti-activation effects, but its mechanism of action is unclear. Our study showed that HSYA inhibited the expression of platelet surface glycoproteins IIß/III α (GPIIß/III α) and thromboxane A2 (TXA2) during platelet activation and reduced platelet Ca2+ accumulation. HSYA significantly reduced the number of platelets and inhibited adrenaline-induced platelet hyperaggregation in rats. Transcriptomic analysis of platelets suggested that HSYA significantly suppressed SRC and MAPK3 (ERK1/2) gene expression. YEEI peptide, an SRC activator, could significantly reverse the inhibition of HSYA on the phosphorylation of SRC/PLCγ2/PKCδ/MEK/ERK1/2 pathway proteins and reverse the effect of HSYA on platelet activation-related markers GPIIß/IIIα protein, TXA2 and cAMP. The SRC genes were further predicted by transcriptome analysis of HSYA-regulated miRNAs combined with bioinformatics techniques. The results suggested that HSYA could significantly upregulate the expression level of the miR-9a-5p gene and further confirmed that miR-9a-5p had a targeted regulatory relationship with SRC by dual-luciferase activity reporter and cell transfection experiments. The inhibitory effect of HSYA on the SRC/PLCγ2/PKCδ/MEK/ERK1/2 pathway was significantly reversed after platelets were transfected with the miR-9a inhibitor, while SRC siRNA attenuated the effect of the miR-9a inhibitor. SRC siRNA was able to attenuate the effect of the miR-9a inhibitor. In conclusion, this study suggests that HSYA can inhibit the activation of the SRC/PLCγ2/PKC δ/MEK/ERK1/2 axis by upregulating platelet miR-9a-5p, thereby reducing the activation of platelets and inhibiting platelet aggregation.

8.
Langmuir ; 39(39): 13890-13896, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37733971

RESUMEN

For the first time, an ionic liquid was grafted onto Ti3C2Tx MXene interlayers (MXene-g-IL) using a radiation technique. The IL was tightly immobilized on the surface of MXene nanosheets via chemical linkage, which exhibited excellent specific capacitance (160 F g-1 at 5 mV s-1) and improved structural stability (maintaining the sheet-like structure for 180 days). The facile, efficient, and scalable synthetic strategy derived from the radiation technique can open a new avenue for covalent functionalization of MXene-based materials and promote their further application.

9.
Anesth Analg ; 136(1): 60-69, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36301724

RESUMEN

BACKGROUND: The effect of anesthesia regimens on postoperative delirium after on-pump cardiac valve surgery is yet undetermined. This study aimed to evaluate the effect of volatile anesthesia compared with propofol-based total intravenous anesthesia (TIVA) on the occurrence of delirium after on-pump cardiac valve surgery. METHODS: This randomized clinical trial was conducted at a university academic hospital in China, from February 2019 to January 2021. Patients scheduled for on-pump cardiac valve surgery or combined valve with coronary artery bypass grafting (CABG) surgeries were randomly assigned to receive anesthesia maintenance with either a volatile anesthetic (sevoflurane or desflurane) or propofol-based TIVA. The primary outcome was the incidence of delirium during the first 7 days after surgery, assessed using the confusion assessment method for the intensive care unit (ICU). The secondary outcomes included duration of delirium, subtypes of delirium, 30-day mortality, pain score, major morbidity (including cerebral infarction, respiratory failure, and pneumonia), duration of mechanical ventilation, and lengths of ICU and hospital stay. The statistical analysis of the primary outcome variable was by Pearson's χ 2 test. RESULTS: Among the 684 patients analyzed (mean age, 53.8 years; 381 [55.7%] women), 676 were assessed for the primary outcome. Postoperative delirium occurred in 63 of 337 (18.7%) patients receiving volatile anesthesia versus 76 of 339 (22.4%) patients receiving propofol-based TIVA (relative risk, 0.80; 95% confidence interval [CI], 0.55-1.16; P = .231). There were no significant differences between the groups in any of the secondary outcomes. CONCLUSIONS: Among patients undergoing on-pump cardiac valve surgery, anesthesia maintenance with a volatile agent did not result in significantly fewer occurrences of postoperative delirium than propofol-based TIVA.


Asunto(s)
Anestésicos por Inhalación , Procedimientos Quirúrgicos Cardíacos , Delirio del Despertar , Propofol , Humanos , Adulto , Femenino , Persona de Mediana Edad , Masculino , Propofol/efectos adversos , Delirio del Despertar/etiología , Anestesia Intravenosa/efectos adversos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Válvulas Cardíacas , Anestésicos Intravenosos/efectos adversos
10.
Scand J Immunol ; 95(1): e13115, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34758123

RESUMEN

Wiskott-Aldrich syndrome (WAS) also called the eczema-thrombocytopenia-immunodeficiency syndrome is a primary immunodeficiency disease with X-linked recessive inheritance caused by mutations in the WAS protein (WASp) gene and characterized by thrombocytopenia with reduced platelet volume, eczema, immunodeficiency, and increased risk of malignant tumours. The mutations will lead to separate WAS severity which can be typical severe 'classical' WAS or less severe 'non-classical' WAS. This article will review and analyse clinical and immune characteristics of five unrelated Chinese families harbouring classical and non-classical WAS. The expression of WASp was detected in the peripheral blood monocytes (PBMC) by flow cytometry, and five mutations were found by WAS gene sequencing, one of which had not been reported in the literature, namely frameshift mutation c.1240_1247delCCACTCCC (p. P414Sfs*41).


Asunto(s)
Leucocitos Mononucleares/metabolismo , Mutación/genética , Proteína del Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/inmunología , China , Análisis Mutacional de ADN , Eccema , Familia , Femenino , Humanos , Lactante , Leucocitos Mononucleares/inmunología , Masculino , Volúmen Plaquetario Medio , Trombocitopenia , Síndrome de Wiskott-Aldrich/genética
11.
Opt Lett ; 47(2): 365-368, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35030607

RESUMEN

We demonstrated a beam conformal projection system for coherent combining of large-scale lasers over 2.1 km in turbulence 20 m above the ground, using the basic modules of a 19-element fiber phased array combined with coarse pointing by a gimbal mount. After coarse pointing and aberration corrections, the metrics (reflected light) of the combined beams from a basic module were best increased by 13.4 times, suggesting that our system promises the great effect of coherent combining under long-distance turbulence. Moreover, we tentatively realized coherent combining of two basic modules (38 lasers), which is the largest number of elements in a fiber laser coherent beam combination outdoors, to the best of our knowledge, with the metrics of combined beams increased by about 29 times.

12.
J Cardiothorac Vasc Anesth ; 36(10): 3758-3765, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35863984

RESUMEN

OBJECTIVES: The purpose of this study was to evaluate the effect of volatile anesthesia and propofol-based total intravenous anesthesia (TIVA) on postoperative pulmonary complications (PPCs) among patients undergoing cardiac surgery. DESIGN: Parallel-group, randomized controlled trial. SETTING: Single-center tertiary care hospital. PARTICIPANTS: Five hundred twenty-four patients undergoing cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: The patients were assigned randomly (1:1) to receive anesthesia maintenance with a volatile anesthetic (sevoflurane or desflurane) or propofol-based TIVA. MEASUREMENTS AND MAIN RESULTS: The primary outcome was a composite of postoperative pulmonary complications within the first 7 postoperative days. The PPCs occurred in 118 of 262 patients (45.0%) in the volatile anesthesia group compared with 105 of 262 patients (40.1%) in the propofol-based intravenous anesthesia group (relative risk: 1.17 [95% CI 0.96-1.42], p = 0.123). There were no significant differences in the severity of PPCs within 7 days postoperatively, the occurrence and severity grade of PPCs within 30 days, the incidence of hypoxia, and 30-day mortality. CONCLUSIONS: In adult patients undergoing cardiac surgery with cardiopulmonary bypass, general anesthesia with a volatile anesthetic compared with propofol-based TIVA had not reduced pulmonary complications within the first 7 days after surgery.


Asunto(s)
Anestésicos por Inhalación , Procedimientos Quirúrgicos Cardíacos , Propofol , Adulto , Anestesia General , Anestesia Intravenosa/efectos adversos , Anestésicos por Inhalación/efectos adversos , Anestésicos Intravenosos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Propofol/efectos adversos
13.
Zhongguo Zhong Yao Za Zhi ; 47(7): 1881-1887, 2022 Apr.
Artículo en Zh | MEDLINE | ID: mdl-35534258

RESUMEN

This study employed Box-Behnken design combined with flux attenuation to explore the nanofiltration conditions for separation of alcohol precipitation liquid during the preparation of Reduning Injection and discussed the applicability of nanofiltration in the separation of the liquid with high-concentration ethanol. The effects of nanofiltration molecular weight cut-off(MWCO) and pH on the rejection of chlorogenic acid, 3,5-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid were consistent with the principles of pore size sieving and charge effect, respectively. The rejection of the three phenolic acids was reduced by concentration polarization effect caused by trans-membrane pressure(TMP). The swelling of membrane surface decreased the pore size and membrane flux for effective separation. Chlorogenic acid and 4,5-dicaffeoylquinic acid were more sensitive to pH and ethanol concentration than 3,5-dicaffeoylquinic acid. A certain correlation existed between the compound structure and the separation factors of nanofiltration, and the separation rules were associated with the comprehensive effect of charge effect, pore size sieving, concentration polarization, steric hindrance and so on.


Asunto(s)
Ácido Clorogénico , Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/química , Etanol , Inyecciones
14.
Opt Express ; 29(1): 359-367, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33362121

RESUMEN

Conventional beam scanning systems employing a microlens array (MLA) suffer from the problem that only discrete diffraction angles can be addressed because of the periodic structure of the MLA. In this paper, an adaptive fiber-optics collimator (AFOC) that continuously adjusts the position of light source (optic fiber output) is used in front of the periodic structure as a moving linear phase shifter to overcome this discrete scanning angle problem. By introducing the AFOC into the beam scanning system employing MLA, a beam scanning system with continuous scanning capability and high resolution is fulfilled. Theoretical simulations and experimental results both demonstrate the continuous high-resolution scanning capacity of the beam scanning system employing both MLA and AFOC. The proposed beam scanning system is expected to find wide applications in space optical communication, optical interconnection, power projection, and coherent beam combining.

15.
J Cardiothorac Vasc Anesth ; 35(8): 2438-2446, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33183935

RESUMEN

OBJECTIVES: Sternal incisions can generate persistent and intense post-sternotomy pain. Propofol has been shown to improve postoperative analgesia, but the preventive effect on persistent pain after cardiac surgery is unknown. The hypothesis of the present study was that intraoperative propofol-based anesthesia compared with volatile anesthesia could reduce the risk of chronic pain after cardiac surgery. DESIGN: A single-center, two-arm, patient-and-evaluator-blinded, randomized controlled trial. SETTING: A single major urban teaching and university hospital. PATIENTS: Five-hundred adult patients undergoing cardiac surgery via sternotomy randomly were assigned. With six withdrawals from the study and five from surgery, 244 in the total intravenous anesthesia group and 245 in the volatile group were included in the modified intention-to-treat analysis. INTERVENTIONS: Patients randomly were assigned to receive either propofol-based total intravenous anesthesia or volatile anesthesia during surgery. MEASUREMENTS AND MAIN RESULTS: The primary outcomes were the incidence of pain at three, six, and 12 months after surgery defined as pain score >0 on the numeric rating scale. The secondary outcomes included acute pain, opioid use during the first 72 hours after surgery, and quality of life. The use of propofol did not significantly affect chronic pain at three months (55.4% v 52.9%, difference 2.5%, 95% confidence interval [CI] -6.6 to 11.6; p = 0.656), six months (35.5% v 37.5%, difference -2.0%, 95% CI -10.9 to 6.9; p = 0.657), or 12 months (18.2% v 20.7%, difference -2.5%, 95% CI -9.8 to 4.8; p = 0.495) compared with volatile anesthetics. Furthermore, there were no differences in acute pain score; morphine-equivalent consumption during the first 72 hours; and quality of life at three, six, and 12 months after surgery. CONCLUSIONS: Intraoperative administration of propofol did not reduce persistent pain after cardiac surgery compared with volatile anesthetics.


Asunto(s)
Dolor Agudo , Anestésicos por Inhalación , Procedimientos Quirúrgicos Cardíacos , Propofol , Adulto , Anestésicos por Inhalación/efectos adversos , Anestésicos Intravenosos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Humanos , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Calidad de Vida
16.
Sensors (Basel) ; 22(1)2021 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-35009670

RESUMEN

We propose an imaging method based on optical fiber bundle combined with micro-scanning technique for improving image quality without complex image reconstruction algorithms. In the proposed method, a piezoelectric-ceramic-chip is used as the micro-displacement driver of the optical fiber bundle, which has the advantages of small volume, fast response speed and high precision. The corresponding displacement of the optical fiber bundle can be generated by precise voltage controlling. An optical fiber bundle with core/cladding diameter 4/80 µm and hexagonal arrangement is used to scan the 1951 USAF target. The scanning step is 1 µm, which is equivalent to the diffraction limit resolution of the optical system. The corresponding information is recorded at high speed through photo-detectors and a high-resolution image is obtained by image stitching processing. The minimum distinguishable stripe width of the proposed imaging technique with piezoelectric-ceramic-chip driven micro-scanning is approximately 2.1 µm, which is 1 time higher than that of direct imaging with a CCD camera whose pixel size is close to the fiber core size. The experimental results indicate that the optical fiber bundle combined with piezoelectric-ceramic-chip driven micro-scanning is a high-speed and high-precision technique for high-resolution imaging.

17.
Hemoglobin ; 45(5): 318-321, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35514176

RESUMEN

ß-Thalassemia (ß-thal), one of the most common form of single-gene inheritable blood diseases in the world, is highly prevalent in southern China, especially in the Guangxi Zhuang Autonomous Region. To update the ß-thal mutation spectrum in this region, we performed hematological and genetic analyses on 888 ß-thal major (ß-TM), ß-thal intermedia (ß-TI) and ß-thal carrier patients, aged 0-15 years old, from different parts of Guangxi Province. We identified 55 genotypes and 18 ß-thal mutations. The codons 41/42 (-TTCT) (HBB: c.126_129delCTTT) (43.97%), codon 17 (A>T) (HBB: c.52A>T) (25.43%), -28(A>G) (HBB: c.-78A>G) (8.18%), IVS-II-654 (C>T) (HBB: c.316-197C>T) (7.85%) and codon 26 (G>A) (HBB: c.79G>A) (5.02%) were the five most common, accounting for more than 90.0%. The results of our study are providing an up-to-date ß-thal mutation spectrum in the 0-15-year-old pediatric population, which will help genetic counseling and prevention of ß-TM in mainland China's most endemic region, Guangxi Zhuang Autonomous Region.


Asunto(s)
Talasemia beta , Adolescente , Niño , Preescolar , China/epidemiología , Codón , Frecuencia de los Genes , Genotipo , Humanos , Lactante , Recién Nacido , Mutación , Globinas beta/genética , Talasemia beta/epidemiología , Talasemia beta/genética
18.
Opt Lett ; 45(7): 1906-1909, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32236029

RESUMEN

In this Letter, we propose and demonstrate efficient adaptive optics correction of a distributed 19-element fiber laser array for both receiving and transmission for the first time, to our best knowledge. Active beam coupling from space into polarization-maintaining fibers and all-fiber active cophasing beam combining with multiple-level fiber couplers are performed. Phase distortions distributed throughout the optical path from the simulated target to the receiving port are eliminated, and nearly ideal coherent combining is achieved in the far-field. Comprehensive reception efficiency is raised up to 52 times with the whole equivalent aperture of 152 mm and the far-field power-in-the-bucket metric up to 8.27 times. The optimal array element parameters for a given whole array aperture and turbulence intensity are analyzed.

19.
Pharmacol Res ; 159: 105031, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32562816

RESUMEN

Thrombosis initiated by abnormal platelet aggregation is a pivotal pathological event that precedes most cases of cardiovascular diseases (CVD). Recently, growing evidence indicates that platelet could be a potential target for CVD prevention. However, as the conventional antithrombotic management strategy, applications of current antiplatelet agents are somewhat limited by their various side effects, such as bleeding risk and drug resistance. Hence, efforts have been made to search for agents as complementary therapies. Ginsenoside, the principal active component extracted from Panax ginseng, has gained much attention for its regulations on multiple crucial events of platelet aggregation. From structural characteristics to clinical applications, this review anatomized the intrinsic structure-function relationship of antiplatelet potency of ginsenosides, and the involved signal pathways were specifically summarized. Additionally, the emphasis was placed on clinical studies that investigate the antithrombotic efficacy of ginsenosides in the treatment of CVD. Further, a broad overview of approaches for improving the bioavailability of ginsenosides was concluded. Limitations and prospects of current studies were also discussed. This study may provide some new insights into the systematic understanding of ginsenosides in CVD treatment and lay a foundation for future research.


Asunto(s)
Plaquetas/efectos de los fármacos , Fármacos Cardiovasculares/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Ginsenósidos/uso terapéutico , Músculo Liso Vascular/efectos de los fármacos , Neointima , Inhibidores de Agregación Plaquetaria/uso terapéutico , Agregación Plaquetaria/efectos de los fármacos , Remodelación Vascular/efectos de los fármacos , Animales , Disponibilidad Biológica , Plaquetas/metabolismo , Fármacos Cardiovasculares/efectos adversos , Fármacos Cardiovasculares/farmacocinética , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/patología , Ginsenósidos/efectos adversos , Ginsenósidos/farmacocinética , Humanos , Estructura Molecular , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/farmacocinética , Transducción de Señal , Relación Estructura-Actividad
20.
Appl Opt ; 59(34): 10754-10760, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33361895

RESUMEN

The technology of a microlens array scanner (MLAS) has the potential to realize large-angle beam scanning with a large beam size. Two sets of microlens arrays (MLAs) were used as phase-controlling emitters in MLAS. A mathematical model of the MLAS with Kepler structure was established in the desired direction and leakage direction. It was verified that the maximum relative displacement of MLAS was half of the MLA sub-aperture. Two sets of F/5 continuous surface MLAs were used as emitters in the experiment. One-dimensional discrete-addressing scanning process with ∼10∘ field of view is demonstrated, and it is in good agreement with the theory.

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