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1.
Hum Brain Mapp ; 44(10): 4165-4182, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37195040

RESUMEN

Understanding the evolutionarily conserved feature of functional laterality in the habenula has been attracting attention due to its potential role in human cognition and neuropsychiatric disorders. Deciphering the structure of the human habenula remains to be challenging, which resulted in inconsistent findings for brain disorders. Here, we present a large-scale meta-analysis of the left-right differences in the habenular volume in the human brain to provide a clearer picture of the habenular asymmetry. We searched PubMed, Web of Science, and Google Scholar for articles that reported volume data of the bilateral habenula in the human brain, and assessed the left-right differences. We also assessed the potential effects of several moderating variables including the mean age of the participants, magnetic field strengths of the scanners and different disorders by using meta-regression and subgroup analysis. In total 52 datasets (N = 1427) were identified and showed significant heterogeneity in the left-right differences and the unilateral volume per se. Moderator analyses suggested that such heterogeneity was mainly due to different MRI scanners and segmentation approaches used. While inversed asymmetry patterns were suggested in patients with depression (leftward) and schizophrenia (rightward), no significant disorder-related differences relative to healthy controls were found in either the left-right asymmetry or the unilateral volume. This study provides useful data for future studies of brain imaging and methodological developments related to precision habenula measurements, and also helps to further understand potential roles of the habenula in various disorders.


Asunto(s)
Habénula , Humanos , Habénula/diagnóstico por imagen , Cognición , Imagen por Resonancia Magnética , Lateralidad Funcional
2.
Small ; 19(45): e2304529, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37434332

RESUMEN

Stretchable wearable thermoelectric (TE) generators (WTEGs) without compromising output performance for real wearables have attracted much attention recently. Herein, a 3D thermoelectric generator with biaxial stretchability is constructed on the device level. Ultraflexible inorganic Ag/Ag2 Se strips are sewn into the soft purl-knit fabric, in which the thermoelectric legs are aligned in the direction of vertical heat flux. A stable and sufficient temperature gradient of 5.2 °C across the WTEG is therefore achieved when contacted with the wrist at a room temperature of 26.3 °C. The prepared TEG generates a high power density of 10.02 W m-2 at a vertical temperature gradient of 40 K. Meanwhile, the reliable energy harvesting promises a variation of less than 10% under the biaxial stretching up to 70% strain via leveraging the combined effects of the stretchability of knit fabric and geometry of TE strips. The knit fabric-supported TEG enables a seamless conformation to the skin as well as efficient body heat harvesting, which can provide sustainable energy to low power consumption wearable electronics.

3.
BMC Health Serv Res ; 23(1): 236, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36899370

RESUMEN

BACKGROUND: Previous studies showed that same-hospital readmission is associated with better outcomes than different-hospital readmission. However, little is known about whether readmission to the same care unit (same-care unit readmission) after infectious hospitalization performs better than readmission to a different care unit at the same hospital (different-care unit readmission). METHODS: This retrospective study screened patients rehospitalized within 30 days following admission to two acute medical wards for infectious diseases from 2013 to 2015 and included only those readmitted for unplanned medical reasons. Outcomes of interest included hospital mortality and length of stay of readmitted patients. RESULTS: Three hundred and fifteen patients were included; of those, 149(47%) and 166(53%) were classified as same-care unit and different-care unit readmissions, respectively. Same-care unit patients were more likely to be older(76 years vs. 70 years; P = 0.001), have comorbid chronic kidney disease(20% vs. 9%; P = 0.008), and have a shorter time to readmission(13 days vs. 16 days; P = 0.020) than different-care unit patients. Univariate analysis showed that same-care unit patients had a shorter length of stay than different-care unit patients(13 days vs. 18 days; P = 0.001), but had similar hospital mortality(20% vs. 24%; P = 0.385). The multivariable linear regression model indicated that same-care unit readmission was associated with a 5-day shorter hospital stay than different-care unit readmission(P = 0.002). CONCLUSION: Among patients readmitted within 30 days after hospitalization for infectious diseases, same-care unit readmission was associated with a shorter length of hospital stay than different-care unit readmission. Whenever feasible, it is encouraged to allocate a readmitted patient to the same care unit in hope of pursuing continuity and quality of care.


Asunto(s)
Enfermedades Transmisibles , Readmisión del Paciente , Humanos , Estudios Retrospectivos , Hospitalización , Tiempo de Internación , Factores de Riesgo
4.
Neuroimage ; 262: 119534, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-35931311

RESUMEN

Lateralization is a fundamental characteristic of many behaviors and the organization of the brain, and atypical lateralization has been suggested to be linked to various brain-related disorders such as autism and schizophrenia. Right-handedness is one of the most prominent markers of human behavioural lateralization, yet its neurobiological basis remains to be determined. Here, we present a large-scale analysis of handedness, as measured by self-reported direction of hand preference, and its variability related to brain structural and functional organization in the UK Biobank (N = 36,024). A multivariate machine learning approach with multi-modalities of brain imaging data was adopted, to reveal how well brain imaging features could predict individual's handedness (i.e., right-handedness vs. non-right-handedness) and further identify the top brain signatures that contributed to the prediction. Overall, the results showed a good prediction performance, with an area under the receiver operating characteristic curve (AUROC) score of up to 0.72, driven largely by resting-state functional measures. Virtual lesion analysis and large-scale decoding analysis suggested that the brain networks with the highest importance in the prediction showed functional relevance to hand movement and several higher-level cognitive functions including language, arithmetic, and social interaction. Genetic analyses of contributions of common DNA polymorphisms to the imaging-derived handedness prediction score showed a significant heritability (h2=7.55%, p <0.001) that was similar to and slightly higher than that for the behavioural measure itself (h2=6.74%, p <0.001). The genetic correlation between the two was high (rg=0.71), suggesting that the imaging-derived score could be used as a surrogate in genetic studies where the behavioural measure is not available. This large-scale study using multimodal brain imaging and multivariate machine learning has shed new light on the neural correlates of human handedness.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Lateralidad Funcional , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos
5.
Dermatol Ther ; 35(9): e15693, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35791845

RESUMEN

Multiple approaches are used to treat acne scars, but some are expensive, ineffective, and cause complications. We aimed to evaluate the efficacy and safety of ultra-pulsed CO2 fractional laser combined with 30% supramolecular salicylic acid in the treatment of acne scars in a prospective split-face control study. Twenty patients with facial symmetrical acne scars were enrolled. One side of face was randomly treated with 30% supramolecular salicylic acid, and two sides were treated with ultra-pulsed CO2 fractional laser. The Echelle d'evaluation clinique des cicatrices d'acne (ECCA) scale was used to evaluate the clinical efficacy before and 3 months after treatment, and a quartile scale was used to self-evaluate the improvement of patients. A visual analog scale was used to record pain scores after each treatment, and side effects and other adverse reactions on the face were recorded. All the patients completed treatment and follow-up. There was statistical difference in ECCA scores of bilateral facial acne scars after three treatments (p < 0.001). ECCA scores on the combined side were lower after three treatments than those on the laser side (p = 0.003). The patient satisfaction quartile scale on the combined side was higher than that on the laser side alone (p = 0.015). Ultra-pulsed CO2 fractional laser combined with 30% supramolecular salicylic acid has better efficacy in the treatment of acne scars than laser alone, and patient self-assessment of combined treatment has a greater degree of improvement in acne scars, and does not increase patient pain scores and related adverse reactions.


Asunto(s)
Acné Vulgar , Láseres de Gas , Acné Vulgar/complicaciones , Dióxido de Carbono , Cicatriz/diagnóstico , Cicatriz/etiología , Cicatriz/terapia , Humanos , Láseres de Gas/efectos adversos , Dolor/etiología , Estudios Prospectivos , Ácido Salicílico/efectos adversos , Resultado del Tratamiento
7.
Clin Infect Dis ; 73(11): e3949-e3955, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-33165503

RESUMEN

BACKGROUND: We evaluated an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine for immunogenicity and safety in adults aged 18-59 years. METHODS: In this randomized, double-blinded, controlled trial, healthy adults received a medium dose (MD) or a high dose (HD) of the vaccine at an interval of either 14 days or 28 days. Neutralizing antibody (NAb) and anti-S and anti-N antibodies were detected at different times, and adverse reactions were monitored for 28 days after full immunization. RESULTS: A total of 742 adults were enrolled in the immunogenicity and safety analysis. Among subjects in the 0, 14 procedure, the seroconversion rates of NAb in MD and HD groups were 89% and 96% with geometric mean titers (GMTs) of 23 and 30, respectively, at day 14 and 92% and 96% with GMTs of 19 and 21, respectively, at day 28 after immunization. Anti-S antibodies had GMTs of 1883 and 2370 in the MD group and 2295 and 2432 in the HD group. Anti-N antibodies had GMTs of 387 and 434 in the MD group and 342 and 380 in the HD group. Among subjects in the 0, 28 procedure, seroconversion rates for NAb at both doses were both 95% with GMTs of 19 at day 28 after immunization. Anti-S antibodies had GMTs of 937 and 929 for the MD and HD groups, and anti-N antibodies had GMTs of 570 and 494 for the MD and HD groups, respectively. No serious adverse events were observed during the study period. CONCLUSIONS: Adults vaccinated with inactivated SARS-CoV-2 vaccine had NAb as well as anti-S/N antibody and had a low rate of adverse reactions. CLINICAL TRIALS REGISTRATION: NCT04412538.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , Método Doble Ciego , Humanos , Inmunogenicidad Vacunal
8.
J Surg Res ; 267: 25-36, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34126390

RESUMEN

BACKGROUND: This study aimed to determine the disease characteristics and prognosis of patients with primary mediastinal nonseminomas (PMNS) in a Surveillance, Epidemiology, and End Results (SEER) analysis. MATERIALS AND METHODS: Demographic, treatment, and survival outcome data of cases with PMNS from 1975 to 2016 were retrieved. Cases with unknown variables mentioned in the analysis were excluded. Relative statistical methods were applied to analyze clinical characteristics and prognosis. RESULTS: A total of 587 PMNS patients met the selection criteria, 526 of whom were men. The mean age of patients was 28 (1-85) y. A total of 511 PMNS patients had validated subtypes, including 172 mixed germ cell tumors, 117 yolk sac tumors, 111 malignant teratomas, 70 choriocarcinomas, and 41 embryonal carcinomas. Patients with yolk sac tumors had the highest 3-y cancer-specific survival (CSS) rate (66.9%), while those with choriocarcinoma and embryonal carcinoma showed the worst prognosis. Surgery + chemotherapy (46.2%) was the most common and effective treatment for each subtype of PMNS. Multivariate Cox proportional hazards analysis identified embryonal carcinoma, malignant teratoma, choriocarcinoma, tumor size >15 cm, nodal metastasis, and distant stage as risk factors. In contrast, surgery-based care and younger age were protective factors. Propensity score matching analysis revealed significant improvement in the 5-y CSS rate from 35.8% to 60.3% with surgery (P < 0.001). However, radiotherapy (P = 0.436) and chemotherapy (P = 0.978) showed no survival benefits. CONCLUSIONS: 10 percent of the PMNS patients were female. Choriocarcinomas and embryonal carcinomas had the worst prognosis. Surgery was demonstrated to be the only way to prolong survival time. Chemotherapy and radiotherapy had minimal effects on prognosis.


Asunto(s)
Neoplasias de Células Germinales y Embrionarias , Neoplasias Testiculares , Neoplasias Uterinas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Embrionario , Niño , Preescolar , Coriocarcinoma/epidemiología , Tumor del Seno Endodérmico , Femenino , Humanos , Lactante , Masculino , Neoplasias del Mediastino , Persona de Mediana Edad , Neoplasias de Células Germinales y Embrionarias/epidemiología , Embarazo , Pronóstico , Programa de VERF , Teratoma , Estados Unidos , Neoplasias Uterinas/epidemiología , Adulto Joven
9.
Nature ; 527(7579): 539-543, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26524521

RESUMEN

Many peroxy-containing secondary metabolites have been isolated and shown to provide beneficial effects to human health. Yet, the mechanisms of most endoperoxide biosyntheses are not well understood. Although endoperoxides have been suggested as key reaction intermediates in several cases, the only well-characterized endoperoxide biosynthetic enzyme is prostaglandin H synthase, a haem-containing enzyme. Fumitremorgin B endoperoxidase (FtmOx1) from Aspergillus fumigatus is the first reported α-ketoglutarate-dependent mononuclear non-haem iron enzyme that can catalyse an endoperoxide formation reaction. To elucidate the mechanistic details for this unique chemical transformation, we report the X-ray crystal structures of FtmOx1 and the binary complexes it forms with either the co-substrate (α-ketoglutarate) or the substrate (fumitremorgin B). Uniquely, after α-ketoglutarate has bound to the mononuclear iron centre in a bidentate fashion, the remaining open site for oxygen binding and activation is shielded from the substrate or the solvent by a tyrosine residue (Y224). Upon replacing Y224 with alanine or phenylalanine, the FtmOx1 catalysis diverts from endoperoxide formation to the more commonly observed hydroxylation. Subsequent characterizations by a combination of stopped-flow optical absorption spectroscopy and freeze-quench electron paramagnetic resonance spectroscopy support the presence of transient radical species in FtmOx1 catalysis. Our results help to unravel the novel mechanism for this endoperoxide formation reaction.


Asunto(s)
Aspergillus fumigatus/enzimología , Biocatálisis , Ácidos Cetoglutáricos/metabolismo , Endoperóxidos de Prostaglandina/biosíntesis , Sitios de Unión , Cristalografía por Rayos X , Espectroscopía de Resonancia por Spin del Electrón , Hemo , Hidroxilación , Indoles/metabolismo , Hierro/metabolismo , Oxígeno/metabolismo , Tirosina/metabolismo
10.
Neuroimage ; 215: 116782, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32276054

RESUMEN

Recent evidence shows that hippocampal theta oscillations, usually linked to memory and navigation, are also observed during online language processing, suggesting a shared neurophysiological mechanism between language and memory. However, it remains to be established what specific roles hippocampal theta oscillations may play in language, and whether and how theta mediates the communication between the hippocampus and the perisylvian cortical areas, generally thought to support language processing. With whole-head magnetoencephalographic (MEG) recordings, the present study investigated these questions with two experiments. Using a violation paradigm, extensively used for studying neural underpinnings of different aspects of linguistic processing, we found increased theta power (4-8 â€‹Hz) in the hippocampal formation, when participants read a semantically incorrect vs. correct sentence ending. Such a pattern of results was replicated using different sentence stimuli in another cohort of participants. Importantly, no significant hippocampal theta power increase was found when participants read a semantically correct but syntactically incorrect sentence ending vs. a correct sentence ending. These findings may suggest that hippocampal theta oscillations are specifically linked to lexical-semantic related processing, and not general information processing in sentence reading. Furthermore, we found significantly transient theta phase coupling between the hippocampus and the left superior temporal gyrus, a hub area of the cortical network for language comprehension. This transient theta phase coupling may provide an important channel that links the memory and language systems for the generation of sentence meaning. Overall, these findings help specify the role of hippocampal theta in language, and provide a novel neurophysiological mechanism at the network level that may support the interface between memory and language.


Asunto(s)
Hipocampo/fisiología , Lenguaje , Memoria/fisiología , Ritmo Teta , Adolescente , Adulto , Mapeo Encefálico , Femenino , Humanos , Magnetoencefalografía , Masculino , Lectura , Semántica , Adulto Joven
11.
Yi Chuan ; 41(8): 761-772, 2019 Aug 20.
Artículo en Zh | MEDLINE | ID: mdl-31447427

RESUMEN

Genetic resources are important national strategic resources. Their preservation, protection and rational utilization form a solid foundation to guarantee national security and to build national competitiveness for the future. Due to a relatively late starting point, China is actively catching up with global peers in storing genetic samples and data. In view of this, in 2011 China approved a plan to build its first nation-level comprehensive gene bank, the China National GeneBank (CNGB), and entrusted BGI-Research to implement its construction and operation. It is China's first gene bank for "reading, writing and storing" bioresources. In this paper, we summarize the development of influential platforms at home and abroad, and focus on CNGB's position, mission, and its structure of "Three Banks and Two Platforms". CNGB launched its official operation in September 2016 and aims to develop a world-class, non-profit and strategic platform that supports science and technology development. It has built capacities to store tens of millions of traceable samples and to analyze handreds of thousanda of WGS each year. It has also set up China's first Pb-level digitalization platform and a high-efficient synthesis platform with a production rate of ten million bases per year. Based on such capacities, CNGB has established its open sharing mechanism for biological samples and data, provided public platform services for life science research, and achieved initial results in supporting innovation and development of the bio-industry.


Asunto(s)
Bases de Datos Genéticas , Investigación , China , Difusión de la Información
12.
Neuroimage ; 178: 92-103, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29772381

RESUMEN

In rodents, hippocampal cell assemblies formed during learning of a navigation task are observed to re-emerge during resting (offline) periods, accompanied by high-frequency oscillations (HFOs). This phenomenon is believed to reflect mechanisms for strengthening newly-formed memory traces. Using magnetoencephalography recordings and a beamforming source location algorithm (synthetic aperture magnetometry), we investigated high-gamma (80-140 Hz) oscillations in the hippocampal region in 18 human participants during inter-trial rest periods in a virtual navigation task. We found right hippocampal gamma oscillations mirrored the pattern of theta power in the same region during navigation, varying as a function of environmental novelty. Gamma power during inter-trial rest periods was positively correlated with theta power during navigation in the first task set when the environment was new and predicted greater performance improvement in the subsequent task set two where the environment became familiar. These findings provide evidence for human hippocampal reactivation accompanied by high-gamma activities immediately after learning and establish a link between hippocampal high-gamma activities and subsequent memory performance.


Asunto(s)
Ritmo Gamma/fisiología , Hipocampo/fisiología , Magnetoencefalografía/métodos , Aprendizaje por Laberinto/fisiología , Consolidación de la Memoria/fisiología , Giro Parahipocampal/fisiología , Navegación Espacial/fisiología , Adolescente , Adulto , Humanos , Masculino , Descanso , Ritmo Teta , Realidad Virtual , Adulto Joven
13.
Anal Chem ; 90(6): 3793-3801, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29443510

RESUMEN

Detailed glycan structural characterization is frequently achieved by collisionally activated dissociation (CAD) based sequential tandem mass spectrometry (MS n) analysis of permethylated glycans. However, it is challenging to implement MS n ( n > 2) during online glycan separation, and this has limited its application to analysis of complex glycan mixtures from biological samples. Further, permethylation can reduce liquid chromatographic (LC) resolution of isomeric glycans. Here, we studied the electronic excitation dissociation (EED) fragmentation behavior of native glycans with a reducing-end fixed charge tag and identified key spectral features that are useful for topology and linkage determination. We also developed a de novo glycan sequencing software that showed remarkable accuracy in glycan topology elucidation based on the EED spectra of fixed charge-derivatized glycans. The ability to obtain glycan structural details at the MS2 level, without permethylation, via a combination of fixed charge derivatization, EED, and de novo spectral interpretation, makes the present approach a promising tool for comprehensive and rapid characterization of glycan mixtures.


Asunto(s)
Oligosacáridos/análisis , Polisacáridos/química , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Electrones , Isomerismo , Análisis de Secuencia/métodos , Programas Informáticos
14.
Appl Opt ; 57(27): 8034-8043, 2018 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-30462075

RESUMEN

We present an optimization design for a stereo-photographic system where achromatic double-prism arrays are used in front of the camera lens to reduce chromatic aberration and distortion. Due to the optical properties of the prism, the image formed by a single-prism array exhibits large chromatic aberration and distortion. The chromatic aberration and distortion for both single-prism array and double-prism array stereo-photographic systems were analyzed by the CODE V software. The double-prism arrays have larger distortion, but the chromatic aberration is small. The distortion arising from the double-prism arrays can be compensated by the camera lens design. The design results show that the maximum spot size is reduced from 17.7 µm to 8.8 µm after optimization. The proposed stereo-photographic system has high-quality stereo images.

15.
Hum Brain Mapp ; 38(3): 1347-1361, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27813230

RESUMEN

Low frequency theta band oscillations (4-8 Hz) are thought to provide a timing mechanism for hippocampal place cell firing and to mediate the formation of spatial memory. In rodents, hippocampal theta has been shown to play an important role in encoding a new environment during spatial navigation, but a similar functional role of hippocampal theta in humans has not been firmly established. To investigate this question, we recorded healthy participants' brain responses with a 160-channel whole-head MEG system as they performed two training sets of a virtual Morris water maze task. Environment layouts (except for platform locations) of the two sets were kept constant to measure theta activity during spatial learning in new and familiar environments. In line with previous findings, left hippocampal/parahippocampal theta showed more activation navigating to a hidden platform relative to random swimming. Consistent with our hypothesis, right hippocampal/parahippocampal theta was stronger during the first training set compared to the second one. Notably, theta in this region during the first training set correlated with spatial navigation performance across individuals in both training sets. These results strongly argue for the functional importance of right hippocampal theta in initial encoding of configural properties of an environment during spatial navigation. Our findings provide important evidence that right hippocampal/parahippocampal theta activity is associated with environmental encoding in the human brain. Hum Brain Mapp 38:1347-1361, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Ambiente , Lateralidad Funcional/fisiología , Hipocampo/fisiología , Giro Parahipocampal/fisiología , Navegación Espacial/fisiología , Ritmo Teta/fisiología , Adolescente , Adulto , Análisis de Varianza , Mapeo Encefálico , Electroencefalografía , Femenino , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Aprendizaje por Laberinto/fisiología , Factores de Tiempo , Interfaz Usuario-Computador , Adulto Joven
16.
Appl Opt ; 56(3): 446-456, 2017 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-28157896

RESUMEN

A zoom lens design for a 10.2-megapixel digital single-lens reflex (SLR) camera with an advanced photo system type-C (APS-C) CCD image sensor is presented. The proposed zoom lens design consists of four groups of 3× zoom lenses with a focal length range of 17-51 mm. In the optimization process, 107 kinds of Schott glass combined with 26 kinds of plastic materials, as listed in Code V, are used. The best combination of glass and plastic materials is found based on the nd-Vd diagram. The modulation transfer function (MTF) was greater than 0.509 at 42 lp/mm, the lateral chromatic aberration was less than 5 µm, the optical distortion was less than 1.97%, and the relative illumination was greater than 80.05%. We also performed the tolerance analysis with the 2σ (97.7%) position selected and given tolerance tables and results for three zooming positions, which made the design more practical for manufacturing.

17.
Anal Chem ; 88(7): 3440-3, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-26959868

RESUMEN

One of the major challenges in structural characterization of oligosaccharides is the presence of many structural isomers in most naturally occurring glycan mixtures. Although ion mobility spectrometry (IMS) has shown great promise in glycan isomer separation, conventional IMS separation occurs on the millisecond time scale, largely restricting its implementation to fast time-of-flight (TOF) analyzers which often lack the capability to perform electron activated dissociation (ExD) tandem MS analysis and the resolving power needed to resolve isobaric fragments. The recent development of trapped ion mobility spectrometry (TIMS) provides a promising new tool that offers high mobility resolution and compatibility with high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometers when operated under the selected accumulation-TIMS (SA-TIMS) mode. Here, we present our initial results on the application of SA-TIMS-ExD-FTICR MS to the separation and identification of glycan linkage isomers.


Asunto(s)
Polisacáridos/análisis , Polisacáridos/química , Análisis de Fourier , Isomerismo , Espectrometría de Masas , Polisacáridos/aislamiento & purificación
18.
J Neurooncol ; 122(1): 43-51, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25527046

RESUMEN

Chemokines are a superfamily of small heparin-binding cytokines that induce leukocytes to migrate to sites of inflammation or injury through interacting with specific transmembrane G protein-coupled receptors. Currently, attention is focused on chemokine/chemokine receptor pairs and their ability to promote tumor cell migration and angiogenesis. The chemokine receptor CXCR3 is involved in tumor metastasis and is used as a prognostic biomarker. However, its relationship with the clinicopathological features of primary glioblastoma multiforme (pGBM) and its potential prognostic value have yet to be investigated. Here, we report that high CXCR3 expression conferred poor survival in pGBM patients. Further analysis showed that CXCR3 served as an independent prognostic biomarker for pGBM patients. In addition, functional assays indicated that CXCR3 induced glioma cell invasion. Therefore, this evidence indicates CXCR3 is an independent prognostic factor for pGBM patients and promotes an invasive phenotype, which suggests a new potential biotarget for glioblastoma multiforme therapy.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Glioblastoma/metabolismo , Glioblastoma/patología , Receptores CXCR3/metabolismo , Biomarcadores de Tumor/genética , Western Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidad , Técnica del Anticuerpo Fluorescente , Glioblastoma/genética , Glioblastoma/mortalidad , Humanos , Técnicas para Inmunoenzimas , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores CXCR3/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Células Tumorales Cultivadas
19.
Appl Opt ; 54(28): E102-8, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26479638

RESUMEN

An optical design for a new white LED motorcycle headlamp is presented. The motorcycle headlamp designed in this study comprises a white LED module, an elliptical reflector, a parabolic reflector, and a toric lens. The light emitted from the white LED module is located at the first focal point of the elliptical reflector and focuses on the second focal point. The second focal point of the elliptical reflector and the focal point of the parabolic reflector are confocal. We use nonsequential rays to improve the optical efficiency of the compound reflectors. The toric spherical lens allows the device to meet the Economic Commission of Europe, regulation no. 113 (ECE R113). Furthermore, good uniformity is obtained by using aspherical surface optimization of the same toric lens. The reflectivity of the reflector is 95%, and the transmittance of each lens surface is 98%. The average deviation of the high beam is 14.17%, and the optical efficiency is 66.45%.

20.
Appl Opt ; 54(28): E203-9, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26479654

RESUMEN

This paper presents the simulation of an autofocus lens design with large depth of field for a cell phone camera. The object distance of the lens is from infinity to 9.754 mm. When the object distance is from infinity to 550 mm, the value of the modulation transfer function (MTF) is greater than 0.6 for the spatial frequency of 114 lp/mm, the optical distortion is less than 1.5%, and the relative illumination is greater than 67%. When the object distance is from 325 to 9.754 mm, the MTF values is greater than 0.4 for close-up shooting. The optical distortion is less than 1.454%, and the relative illumination is greater than 68.8%.

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