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1.
Graefes Arch Clin Exp Ophthalmol ; 258(7): 1543-1547, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32279089

RESUMO

PURPOSE: To observe the efficacy of modified Snyder-Thompson posterior scleral reinforcement with round scleral patches in Chinese children with high myopia. METHODS: This retrospective study included 46 Chinese children with high myopia (72 eyes) who underwent modified Snyder-Thompson posterior scleral reinforcement (PSR) with round scleral patches and 43 Chinese children with high myopia (67 eyes) who wore only spectacles as a control group. Both groups attended a follow-up at 3 years. Axial length (AL), spherical equivalent (SE), best-corrected visual acuity (BCVA), and full ocular assessment results were evaluated at the initial and final visits. Complications were recorded. RESULTS: AL had increased by 0.29 ± 0.33 mm in the PSR group and 0.82 ± 0.33 mm in the control group (P < 0.0001) at the final follow-up. The change in the SE was 0.31 ± 0.81 D in the PSR group and 2.25 ± 1.02 D in the control group (P < 0.0001). A decrease of 0.02 ± 0.11 LogMAR was found in the control group, and a change of 0.22 ± 0.35 LogMAR was found in the PSR group. No serious complications due to PSR surgery occurred. CONCLUSIONS: Modified Snyder-Thompson PSR surgery with round scleral patches can effectively limit the progression of axial elongation in Chinese children with high myopia. The operation is safe, causes little damage, and can be customized.


Assuntos
Miopia Degenerativa/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Refração Ocular/fisiologia , Esclera/cirurgia , Acuidade Visual , Adolescente , Comprimento Axial do Olho , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Miopia Degenerativa/diagnóstico , Miopia Degenerativa/fisiopatologia , Estudos Retrospectivos , Esclera/diagnóstico por imagem , Microscopia com Lâmpada de Fenda , Fatores de Tempo , Resultado do Tratamento
2.
Sensors (Basel) ; 20(19)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987789

RESUMO

We analyzed the distribution of chlorophyll-a (Chla) in the Bohai Sea area based on data from the geosynchronous orbit optical satellite Gaofen-4 (GF-4), which was launched in 2015, carrying a panchromatic multispectral sensor (PMS). This is the first time the geosynchronous orbit optical satellite GF-4 remote-sensing data has been used in China to detect the Chla change details in the Bohai Sea. A new GF-4 retrieved model was established based on the relationship between in situ Chla value and the reflectance combination of 2 and 4 bands, with the R2 of 0.9685 and the total average relative error of 37.42%. Twenty PMS images obtained from 2017 to 2019 were applied to analyze Chla in Bohai sea. The results show that: (1) the new built Chla inversion model PMS-1 for the GF-4 PMS sensor can extract Chla distribution details in the Bohai Sea well. The high Chla content in the Bohai Sea is mainly located in coastal areas, such as the top of Laizhou Bay, Bohai Bay and Liaodong Bay, with the value being around 13 µg/L. The concentration of Chla in the Bohai Strait and northern Yellow Sea is relatively low with the value being around 5 µg/L. (2). Taking full advantage of the continuous observation of geostationary orbit satellite, GF-4 with a high-resolution sensor PMS of 50 m can effectively detect short-term change (changes within 10 min) in Chla concentration. The changes mainly appear at the southwest and northeast costal area as well as in the center of Bohai Sea with the change value of around 3 µg/L. (3) The change of Chla concentration in the Bohai sea is related to the environmental factors such as seawater temperature, salinity, illumination and nutrient salts, as well as the dynamic factors such as wind, flow field and tidal current.


Assuntos
Monitoramento Ambiental , Água do Mar , China , Clorofila , Clorofila A , Tecnologia de Sensoriamento Remoto
4.
Am J Hum Genet ; 90(1): 40-8, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22226084

RESUMO

Ocular coloboma is a developmental defect of the eye and is due to abnormal or incomplete closure of the optic fissure. This disorder displays genetic and clinical heterogeneity. Using a positional cloning approach, we identified a mutation in the ATP-binding cassette (ABC) transporter ABCB6 in a Chinese family affected by autosomal-dominant coloboma. The Leu811Val mutation was identified in seven affected members of the family and was absent in six unaffected members from three generations. A LOD score of 3.2 at θ = 0 was calculated for the mutation identified in this family. Sequence analysis was performed on the ABCB6 exons from 116 sporadic cases of microphthalmia with coloboma (MAC), isolated coloboma, and aniridia, and an additional mutation (A57T) was identified in three patients with MAC. These two mutations were not present in the ethnically matched control populations. Immunostaining of transiently transfected, Myc-tagged ABCB6 in retinal pigment epithelial (RPE) cells showed that it localized to the endoplasmic reticulum and Golgi apparatus of RPE cells. RT-PCR of ABCB6 mRNA in human cell lines and tissue indicated that ABCB6 is expressed in the retinae and RPE cells. Using zebrafish, we show that abcb6 is expressed in the eye and CNS. Morpholino knockdown of abcb6 in zebrafish produces a phenotype characteristic of coloboma and replicates the clinical phenotype observed in our index cases. The knockdown phenotype can be corrected with coinjection of the wild-type, but not mutant, ABCB6 mRNA, suggesting that the phenotypes observed in zebrafish are due to insufficient abcb6 function. Our results demonstrate that ABCB6 mutations cause ocular coloboma.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Coloboma/genética , Mutação , Transportadores de Cassetes de Ligação de ATP/biossíntese , Animais , Povo Asiático/genética , Sequência de Bases , Linhagem Celular , Sistema Nervoso Central/metabolismo , Éxons , Anormalidades do Olho/genética , Feminino , Humanos , Escore Lod , Masculino , Microftalmia/genética , Pessoa de Meia-Idade , Dados de Sequência Molecular , Morfolinos/administração & dosagem , Epitélio Pigmentado da Retina , Transfecção , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
5.
Strabismus ; 32(1): 23-29, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38509018

RESUMO

PURPOSE: This study is to describe the special clinical and genotypic features of a Chinese family with variant types of Duane retraction syndrome and to present our experience on managing these cases. METHODS: Four individuals from one family were reviewed by ophthalmologic examinations, in which two affected and two unaffected individuals were revealed. MRI scans were performed on the two patients. Relevant gene mutations were screened by the next-generation sequencing technology and confirmed by Sanger sequencing technology. RESULTS: The six-year-old proband presented with special clinical features of severe horizontal gaze dysfunction, exotropia and mild scoliosis. His mother showed significantly limited binocular abductions, with retraction of eyeballs in adduction. From MRI scans, abducens nerves were not observed in both patients and the oculomotor nerve was slightly thin in the proband. The proband and his mother shared the same CHN1 gene mutation site (c. 62A>G; p.Y21C). Strabismus surgery was performed on the proband to correct the primary gaze exotropia.(NM_001822: exon3 or NM_001025201: exon4: c. 62A>G; p.Y21C). CONCLUSIONS: A novel CHN1 gene mutation was revealed from a Chinese family with Duane retraction syndrome. Remarkably, the proband and his mother presented different clinical features of ocular motility disorder. Strabismus correction surgery and amblyopia training helped to improve the appearance and visual function of the proband.


Assuntos
Síndrome da Retração Ocular , Mutação , Linhagem , Adulto , Criança , Feminino , Humanos , Masculino , Povo Asiático/genética , Quimerina 1/genética , China , Análise Mutacional de DNA , Síndrome da Retração Ocular/genética , Síndrome da Retração Ocular/fisiopatologia , População do Leste Asiático , Exotropia/genética , Exotropia/fisiopatologia , Imageamento por Ressonância Magnética
6.
Front Pharmacol ; 15: 1286546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389927

RESUMO

Objective: Our preliminary research indicates that acacetin modulates the nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain containing 3 (NLRP3) inflammasome, providing protection against Alzheimer's Disease (AD) and cerebral ischemic reperfusion injury. The mechanisms of acacetin to inhibit the activation of the NLRP3 inflammasome remain fully elucidated. This study aims to investigate the effects and potential mechanisms of acacetin on various agonists induced NLRP3 inflammasome activation. Methods: A model for the NLRP3 inflammasome activation was established in mouse bone marrow-derived macrophages (BMDMs) using Monosodium Urate (MSU), Nigericin, Adenosine Triphosphate (ATP), and Pam3CSK4, separately. Western blot analysis (WB) was employed to detect Pro-caspase-1, Pro-Interleukin-1ß (Pro-IL-1ß) in cell lysates, and caspase-1, IL-1ß in supernatants. Enzyme-Linked Immunosorbent Assay (ELISA) was used to measured the release of IL-1ß, IL-18, and Tumor Necrosis Factor-alpha (TNF-α) in cell supernatants to assess the impact of acacetin on NLRP3 inflammasome activation. The lactate dehydrogenase (LDH) release was also assessed. The Nuclear Factor Kappa B (NF-κB) and Mitogen-Activated Protein Kinase (MAPK) signaling pathways related proteins were evaluated by WB, and NF-κB nuclear translocation was observed via laser scanning confocal microscopy (LSCM). Disuccinimidyl Suberate (DSS) cross-linking was employed to detect oligomerization of Apoptosis-associated Speck-like protein containing a Caspase Recruitment Domain (ASC), and LSCM was also used to observe Reactive Oxygen Species (ROS) production. Inductively Coupled Plasma (ICP) and N-(6-methoxyquinolyl) acetoethyl ester (MQAE) assays were utilized to determined the effects of acacetin on the efflux of potassium (K+) and chloride (Cl-) ions. Results: Acacetin inhibited NLRP3 inflammasome activation induced by various agonists, reducing the release of TNF-α, IL-1ß, IL-18, and LDH. It suppressed the expression of Lipopolysaccharides (LPS)-activated Phosphorylated ERK (p-ERK), p-JNK, and p-p38, inhibited NF-κB p65 phosphorylation and nuclear translocation. Acacetin also reduced ROS production and inhibited ASC aggregation, thus suppressing NLRP3 inflammasome activation. Notably, acacetin did not affect K+ and Cl-ions efflux during the activation process. Conclusion: Acacetin shows inhibitory effects on both the priming and assembly processes of the NLRP3 inflammasome, positioning it as a promising new candidate for the treatment of NLRP3 inflammasome-related diseases.

7.
J Inflamm Res ; 17: 3641-3652, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855167

RESUMO

Background: Acacetin is a natural flavonoid known for its anti-tumor, antioxidant, and anti-inflammatory properties. Our previous studies have shown its protective effects against cerebral ischemia-reperfusion injury (IRI), but the underlying molecular mechanisms remain unclear. Purpose: The study delves into acacetin's mechanism in mitigating cerebral IRI, with a focus on transcriptomic insights. Methods: We established the oxygen-glucose deprivation/re-oxygenation (OGD/R) model in BV2 microglia, treating them with 10µM acacetin. Then we assessed cell proliferation using CCK-8 and measured Lactate Dehydrogenase (LDH) release. High-throughput RNA sequencing (RNA-seq) underpinned the analysis of differentially expressed genes (DEGs) and long non-coding RNAs (lncRNAs), functional enrichment, and alternative splicing events (ASEs), validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Results: OGD/R injury significantly impaired cell proliferation and increased LDH release, effects mitigated by acacetin. RNA-seq identified 2148 upregulated and 2135 downregulated DEGs post-OGD/R. In contrast, the acacetin-treated group showed 248 upregulated and 240 downregulated DEGs compared to the OGD/R group. All DEGs were enriched in both Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Overlapping analysis indicated that acacetin treatment reversed the expression of 203 genes affected by OGD/R, including inflammation-related genes such as Isg15, Fcgr1, Il1b, and Parp12. Moreover, the oxidative stress-related gene, Mt2, was downregulated post-OGD/R but upregulated following acacetin treatment. We further found that OGD/R and acacetin treatment could modulate gene splicing events, impacting cell apoptosis or inflammatory responses, such as the A3SS splicing event in the Trim47 gene. RNA-seq also highlighted differential expression of numerous lncRNAs, particularly the upregulation of lncRNA Rmrp and Terc post-OGD/R and their subsequent downregulation post-acacetin treatment. These lncRNAs might regulate cell proliferation through mediating target gene expressions. RT-qPCR validation confirmed these findings. Conclusion: Significant upregulation of genes and ASEs linked to oxidative stress and inflammatory response is observed in cerebral IRI. Acacetin intervention reverses these effects, highlighting its mechanism in alleviating the injury by modulating gene expression and splicing events.

8.
J Am Chem Soc ; 135(12): 4799-804, 2013 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-23495667

RESUMO

Current therapy of malignant glioma in clinic is unsatisfactory with poor patient compliance due to low therapeutic efficiency and strong systemic side effects. Herein, we combined chemo-photothermal targeted therapy of glioma within one novel multifunctional drug delivery system. A targeting peptide (IP)-modified mesoporous silica-coated graphene nanosheet (GSPI) was successfully synthesized and characterized, and first introduced to the drug delivery field. A doxorubicin (DOX)-loaded GSPI-based system (GSPID) showed heat-stimulative, pH-responsive, and sustained release properties. Cytotoxicity experiments demonstrated that combined therapy mediated the highest rate of death of glioma cells compared to that of single chemotherapy or photothermal therapy. Furthermore, the IP modification could significantly enhance the accumulation of GSPID within glioma cells. These findings provided an excellent drug delivery system for combined therapy of glioma due to the advanced chemo-photothermal synergistic targeted therapy and good drug release properties of GSPID, which could effectively avoid frequent and invasive dosing and improve patient compliance.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Glioma/tratamento farmacológico , Grafite/química , Dióxido de Silício/química , Antibióticos Antineoplásicos/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Doxorrubicina/farmacologia , Glioma/patologia , Glioma/terapia , Humanos , Hipertermia Induzida , Nanoestruturas/química , Processos Fotoquímicos , Fotoquimioterapia , Prótons , Temperatura
9.
Risk Manag Healthc Policy ; 16: 1531-1544, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602364

RESUMO

Purpose: In this study, the aim was to investigate the prevalence and risk factors of hyperuricemia (HUA) in the urban health checkup population in Urumqi, Xinjiang, and thus provide clues for the prevention of HUA. Methods: People who attended medical examinations from May 2021 to June 2022 at a hospital in Urumqi, Xinjiang, were selected for evaluation based on their general information, physical examination results, and laboratory test results. The chi-square test was used to determine whether there was a difference in the prevalence of HUA among participants with different characteristics. Using logistic regression analyses, risk factors for HUA were identified. Results: There were 8722 participants diagnosed with HUA, with an overall prevalence of 26.96%. The prevalence in men was 37.72%, significantly higher than in women (13.29%). Participants were characterized by a multiethnic composition, with Han (28.61%), Hui (27.88%) and Manchu (38.46%) being the three ethnicities with the highest prevalence. According to logistic regression analyses, HUA was associated with age, ethnicity, residence, marital status, body mass index (BMI), diastolic blood pressure (DBP), fasting blood glucose (FPG), triglyceride glucose (TyG) index, abdominal obesity, and dyslipidemia differently in males and females. Conclusion: The prevalence of HUA was high in the urban health checkup population in Urumqi, Xinjiang, particularly among men and youth. The early intervention for HUA should be enhanced to reduce the risk of cardiovascular disease and other related conditions.

10.
Mol Vis ; 18: 81-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22262941

RESUMO

PURPOSE: Screening of mutations in the fibrillin-1 (FBN1) gene in a Chinese family with autosomal dominant Marfan syndrome (MFS). METHODS: It has been reported that FBN1 mutations account for approximately 90% of Autosomal Dominant MFS. FBN1 mutations were analyzed in a Chinese family of 36 members including 13 MFS patients. The genomic DNAs from blood leukocytes of the patients and their relatives were isolated and the entire coding region of FBN1 was amplified by PCR. The sequence of FBN1 was dertermined with an ABI 3100 Genetic Analyzer. RESULTS: A previously unreported the missense mutation G214S (caused by a 640 A→G heterozygous change) in FBN1 was identified in the Chinese family. The mutation was associated with the disease phenotype in patients, but not detected in their relatives or in the 100 normal controls. CONCLUSIONS: This is the first report of molecular characterization of FBN1 in the MFS family of Chinese origin. Our results expand the spectrum of FBN1 mutations causing MFS and further confirm the role of FBN1 in the pathogenesis of MFS. Direct sequencing of the mutation in FBN1 may be used for diagnosis of MFS.


Assuntos
Povo Asiático , Síndrome de Marfan/genética , Proteínas dos Microfilamentos/genética , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Fibrilina-1 , Fibrilinas , Genes Dominantes , Genótipo , Heterozigoto , Humanos , Masculino , Síndrome de Marfan/metabolismo , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Fases de Leitura Aberta , Linhagem , Fenótipo
11.
Artigo em Zh | MEDLINE | ID: mdl-22311481

RESUMO

OBJECTIVE: To investigate potential mutation of PHOX2A (or ARIX) gene in a Chinese family affected with congenital fibrosis of extraocular muscles tyep 2 (CFEOM2). METHODS: Genomic DNA was obtained from affected and unaffected members of the family. With an ABI PRSIM Linkage Mapping Set-MD10 kit, selected markers flanking the PHOX2A locus were used for linkage analysis. Exons of PHOX2 gene were amplified and sequenced. A total of 100 normal subjects were recruited as controls. RESULTS: Genetic linkage was found at 11q13 between D11S4151 and D11S1320 and the PHOX2A gene. DNA sequencing has identified a heterozygous mutation in the exon 2 of the gene (227T to G, N76K). The same mutation was not found in the unaffected and 100 normal controls. CONCLUSION: A mutation of the PHOX2A gene 227T to G is responsible for the onset of congenital fibrosis of extraocular muscles type 2 in this Chinese family.


Assuntos
Fibrose/genética , Proteínas de Homeodomínio/genética , Mutação , Transtornos da Motilidade Ocular/genética , Músculos Oculomotores/anormalidades , Sequência de Bases , Estudos de Casos e Controles , China , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Linhagem
12.
J Int Bus Stud ; : 1-35, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36597430

RESUMO

Although cross-border acquisitions (CBAs) are prevalent, many such acquisitions fail to complete. This challenge is even more profound for emerging market MNEs (EMNEs). Drawing upon the vicarious learning theory, we argue that EMNEs can learn from inbound foreign acquirers through the latter's demonstration, professional services firms, and employees. This learning mechanism enables EMNEs to better deal with the complexity and uncertainty in various stages of acquiring foreign firms, thus increasing the completion rate of their outbound CBAs. We also suggest that the effectiveness of vicarious learning is further enhanced by the relatedness between inbound and outbound CBAs. Our analysis of 3599 outbound CBAs from 27 emerging economies during 2000-2018 shows that prior inbound CBAs completed in an emerging economy have a positive effect on the completion likelihood of outbound CBAs conducted by EMNEs from this economy. This positive effect becomes even stronger when the percentage of (1) inbound CBAs served by the EMNE's financial advisors, (2) inbound foreign acquirers that are in the same industry as the EMNE, and (3) inbound foreign acquirers that are from the same country as a focal outbound CBA's target country, is larger. These findings offer new insights into the inbound-outbound acquisition links and the internationalization process of EMNEs. Supplementary Information: The online version contains supplementary material available at 10.1057/s41267-022-00583-x.


Bien que les acquisitions transfrontalières (Cross-Border Acquisitions ­ CBAs) soient répandues, nombre d'entre elles ne sont pas menées à bien. Ce défi est encore plus grand pour les multinationales des marchés émergents (Emerging Market MNEs ­ EMNEs). Nous appuyant sur la théorie de l'apprentissage vicariant, nous argumentons que les EMNEs peuvent apprendre des acquéreurs étrangers entrants par le biais des démonstrations de ces derniers, des entreprises de services professionnels et des employés. Ce mécanisme d'apprentissage permet aux EMNEs de mieux gérer la complexité et l'incertitude des différentes étapes de l'acquisition d'entreprises étrangères, augmentant ainsi le taux d'achèvement de leurs CBAs sortantes. Nous suggérons également que l'efficacité de l'apprentissage vicariant est renforcée par la relation entre les CBAs entrantes et sortantes. Notre analyse de 3599 CBAs sortantes de 27 économies émergentes entre 2000 et 2018 montre que les CBAs entrantes antérieures réalisées dans une économie émergente ont un impact positif sur la probabilité d'achèvement des CBAs sortantes réalisées par les EMNEs de cette économie. Cet impact positif devient encore plus fort lorsque le pourcentage (1) de CBAs entrantes servies par les conseillers financiers de l'EMNE, (2) d'acquéreurs étrangers entrants appartenant au même secteur d'activité que l'EMNE, et (3) d'acquéreurs étrangers entrants provenant du même pays que le pays cible d'une CBA sortante focale, est plus élevé. Ces résultats apportent de nouveaux renseignements sur les liens entre les acquisitions entrantes et sortantes, ainsi que sur le processus d'internationalisation des EMNEs.


Aunque las adquisiciones transfronterizas (CBAs por sus iniciales en inglés) son frecuentes, muchas de ellas no consiguen completarse. Este reto es aún más profundo para las empresas multinacionales de mercados emergentes (EMNE por sus iniciales en inglés). Basándonos en la teoría del aprendizaje vicario, argumentamos que las empresas multinacionales de mercados emergentes pueden aprender de los adquirentes extranjeros entrantes a través de la demostración de estos últimos, de las empresas de servicios profesionales y de los empleados. Este mecanismo de aprendizaje permite a las empresas multinacionales de mercados emergentes afrontar mejor la complejidad y la incertidumbre en varias etapas de la adquisición de empresas extranjeras, aumentando así la tasa de finalización de sus adquisiciones transfronterizas salientes. También sugerimos que la eficacia del aprendizaje vicario se ve reforzada por la relación entre las adquisiciones transfronterizas entrantes y salientes. Nuestro análisis de 3.599 adquisiciones transfronterizas salientes de 27 economías emergentes durante 2000­2018 muestra que las adquisiciones transfronterizas entrantes anteriores completados en una economía emergente tienen un efecto positivo en la probabilidad de finalización de las adquisiciones transfronterizas salientes realizados por las empresas multinacionales de mercados emergentes de esta economía. Este efecto positivo se hace aún más fuerte cuando el porcentaje de (1) las adquisiciones transfronterizas entrantes atendidos por los asesores financieros de la empresa multinacional de mercados emergentes, (2) adquirentes extranjeros entrantes que están en la misma industria que la empresa multinacional de mercados emergentes, y (3) adquirentes extranjeros entrantes que son del mismo país que el país objetivo de una adquisición transfronteriza saliente focal, es mayor. Estos resultados ofrecen nuevas perspectivas sobre los vínculos de adquisición entrante-saliente y el proceso de internacionalización de las empresas multinacionales de mercados emergentes.


Embora as aquisições transfronteiriças (CBAs) sejam predominantes, muitas dessas aquisições não têm sucesso na sua conclusão. Esse desafio é ainda mais profundo para MNEs de mercados emergentes (EMNEs). Com base na teoria da aprendizagem vicária, argumentamos que EMNEs podem aprender com compradores estrangeiros entrantes por meio de sua demonstração, empresas de serviços profissionais e funcionários. Esse mecanismo de aprendizagem permite que EMNEs lidem melhor com a complexidade e a incerteza em vários estágios de aquisição de empresas estrangeiras, dessa forma aumentando a taxa de conclusão de suas CBAs. Também sugerimos que a eficácia da aprendizagem vicária é ainda mais reforçada pela relação entre CBAs de entrada e saída. Nossa análise de 3.599 CBAs de saída de 27 economias emergentes durante 2000­2018 mostra que CBAs de entrada anteriores concluídas em uma economia emergente têm um efeito positivo na probabilidade de conclusão de CBAs de saída conduzidas por EMNEs dessa economia. Este efeito positivo torna-se ainda mais pronunciado quando é maior o percentual de (1) CBAs de entrada atendidos por consultores financeiros da EMNE, (2) adquirentes estrangeiros de entrada que são da mesma indústria que a EMNE e (3) adquirentes estrangeiros de entrada que são do mesmo país do destino de uma CBA de saída. Essas descobertas oferecem novos insights sobre as conexões de aquisição de entrada e saída e o processo de internacionalização de EMNEs.

13.
Transl Neurosci ; 13(1): 390-397, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36382256

RESUMO

Background: Acacetin (5,7-dihydroxy-4'-methoxyflavone), one of the main extractions from Saussurea involucrata, has anti-inflammatory effects. Our previous study found that acacetin inhibited the Nod-like receptor pyrin domain containing 3 (NLRP3) signaling pathway after cerebral ischemia-reperfusion injury. NLRP3 inflammasome plays a role in Alzheimer's disease (AD) process. However, few studies have examined the effects of acacetin in AD. Methods: We randomly divided APP swe/PS1dE9 double transgenic mice into acacetin group (intraperitoneal injection of 25 mg/kg acacetin) and AD model group (intraperitoneal injection of same volume of saline). C57BL/6 mice were selected as control group (same treatment with AD model group). After treating for 30 days, a Morris water maze test was conducted to evaluate spatial learning and memory of the mice. Senile plaque (SP) formation was evaluated by immunohistochemistry. NLRP3 inflammasome-related inflammatory factors and amyloid-ß-42 were detected by Western blot or enzyme-linked immunosorbent assay. Results: Acacetin improved spatial learning and memory of AD mice and reduced APP/ß expression, thereby decreasing SP formation in the brain. Acacetin also reduced the expression of NLRP3, cysteinyl aspartate-specific proteinase 1 (caspase-1), and interleukin-1ß (IL-1ß) and the release of inflammatory factors, tumor necrosis factor-α (TNF-α) and IL-1ß. Conclusions: Acacetin improved the learning and memory abilities of AD mice and exerted a protective effect on AD by inhibiting the NLRP3 signaling pathway and reducing SP formation.

14.
Mol Vis ; 17: 2765-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22065930

RESUMO

PURPOSE: To screen mutations in the FERM domain-containing 7 (FRMD7) gene in a Chinese family with X-linked idiopathic congenital nystagmus (ICN). METHODS: It has been reported that FRMD7 mutations account for approximately 47% of X-linked nystagmus in Chinese patients. We collected 5 ml of blood samples from members of a family with X-linked ICN and 100 normal controls. Mutations in FRMD7 were determined by sequencing PCR products. RESULTS: We identified a previously unreported 4 bp deletion in FRMD7 (c.1486-1489 del TTTT) in a Chinese family. The mutation co-segregated with the disease phenotype in patients and female carriers, while it was not detected in other relatives or in the 100 normal controls. CONCLUSIONS: Our results expand the spectrum of FRMD7 mutations causing ICN, and further confirm the role of FRMD7 in the pathogenesis of ICN. Direct sequencing of FRMD7 could be used as a diagnostic testing of idiopathic congenital nystagmus.


Assuntos
Povo Asiático/genética , Proteínas do Citoesqueleto/genética , Mutação da Fase de Leitura , Genes Ligados ao Cromossomo X , Doenças Genéticas Ligadas ao Cromossomo X/genética , Proteínas de Membrana/genética , Nistagmo Congênito/genética , Idoso , Sequência de Bases , Estudos de Casos e Controles , Pré-Escolar , Análise Mutacional de DNA , Feminino , Testes Genéticos , Heterozigoto , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Fenótipo , Deleção de Sequência , Fatores Sexuais
15.
Nanoscale ; 12(8): 5075-5083, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32068223

RESUMO

Fabricating lanthanide doped up-conversion luminescence based nanocomposites has drawn increasing attention in nanoscience and nanotechnology. Although challenging in precise synthesis, structure manipulation and interfacial engineering, fabricating dendritic mesoporous silica coated up-conversion nanoparticles (UCNP@dMSNs) with a tunable pore size is of great importance for the functionalization and application of UCNPs. Herein, we report a strategy to prepare uniform monodisperse UCNP@dMSNs with a core-shell structure. The silica shell has tunable center-radial and dendritic mesoporous channels. The synthesis was carried out in the heterogeneous oil-water microemulsion phase of the Winsor III system reaction system, which allows silica to be deposited directly on hydrophobic UCNPs through the self-anchoring of micelle complexes on the oleic acid ligand. The average pore size of UCNP@dMSNs could be tailored from ∼10 to ∼35 nm according to the varied amounts of co-solvent in the mixture. The microemulsion approach could also be used to prepare hierarchical UCNP@dMSNs with a multi-generational mesostructure. The resultant UCNP@dMSNs exhibit the unique advantage of loading "guest" nanoparticles in a self-absorption manner. We proved that Cu1.8S NPs (∼10 nm), Au NPs (∼10 nm) and Fe3O4 NPs (∼25 nm) could be incorporated in UCNP@dMSNs, which in turn validates the high adsorption capacity of UCNP@dMSNs.

16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 26(3): 263-6, 2009 Jun.
Artigo em Zh | MEDLINE | ID: mdl-19504436

RESUMO

OBJECTIVE: To map the candidate gene by linkage analysis in a Chinese family with autosomal dominant congenital retinaochoroidal coloboma. METHODS: A detailed clinical examination was performed for all patients in the family. The genomic DNA of all family members was extracted from peripheral blood leukocytes. Linkage analysis and genome-wide linkage screening was conducted using fluorescent detection of 398 microsatellite markers representing all autosomes at an average resolution of approximately 10 cM. Polymerase chain reaction was carried out to amplify all 398 microsatellite markers. The allele sizes were determined on ABI 3130-Avant genetic analyzer according to an internal size standard, and the results were analyzed using Genescan 3.1 and Genotyper 2.0 software. RESULTS: Linkage analysis showed the markers D2S2382-D2S301-D2S2244-D2S163 co-segregated with the disease locus in all affected members. The maximum Lod score was 3.01(D2S2382). CONCLUSION: The candidate region of the disease gene in the family was located in 2q34-2q35.


Assuntos
Coloboma/genética , Escore Lod , Repetições de Microssatélites/genética , Miopia/genética , Povo Asiático , Mapeamento Cromossômico , Análise Mutacional de DNA , Família , Feminino , Ligação Genética , Genótipo , Humanos , Perda de Heterozigosidade , Masculino , Linhagem , Reação em Cadeia da Polimerase
17.
Neural Regen Res ; 14(4): 605-612, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30632500

RESUMO

Acacetin (5,7-dihydroxy-4'-methoxyflavone), a potential neuroprotective agent, has an inhibitory effect on lipopolysaccharide-induced neuroinflammatory reactions. However, whether acacetin has an effect on inflammatory corpuscle 3 (NLRP3) after cerebral ischemia-reperfusion injury has not been fully determined. This study used an improved suture method to establish a cerebral ischemia-reperfusion injury model in C57BL/6 mice. After ischemia with middle cerebral artery occlusion for 1 hour, reperfusion with intraperitoneal injection of 25 mg/kg of acacetin (acacetin group) or an equal volume of saline (0.1 mL/10 g, middle cerebral artery occlusion group) was used to investigate the effect of acacetin on cerebral ischemia-reperfusion injury. Infarct volume and neurological function scores were determined by 2,3,5-triphenyltetrazolium chloride staining and the Zea-Longa scoring method. Compared with the middle cerebral artery occlusion group, neurological function scores and cerebral infarction volumes were significantly reduced in the acacetin group. To understand the effect of acacetin on microglia-mediated inflammatory response after cerebral ischemia-reperfusion injury, immunohistochemistry for the microglia marker calcium adapter protein ionized calcium-binding adaptor molecule 1 (Iba1) was examined in the hippocampus of ischemic brain tissue. In addition, tumor necrosis factor-α, interleukin-1ß, and interleukin-6 expression in ischemic brain tissue of mice was quantified by enzyme-linked immunosorbent assay. Expression of Iba1, tumor necrosis factor-α, interleukin-1ß and interleukin-6 was significantly lower in the acacetin group compared with the middle cerebral artery occlusion group. Western blot assay results showed that expression of Toll-like receptor 4, nuclear factor kappa B, NLRP3, procaspase-1, caspase-1, pro-interleukin-1ß, and interleukin-1ß were significantly lower in the acacetin group compared with the middle cerebral artery occlusion group. Our findings indicate that acacetin has a protective effect on cerebral ischemia-reperfusion injury, and its mechanism of action is associated with inhibition of microglia-mediated inflammation and the NLRP3 signaling pathway.

18.
Mol Vis ; 14: 1893-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18958302

RESUMO

PURPOSE: To map a gene responsible for infantile cataract in a large four-generation, non-consanguineous Chinese family. METHODS: Twenty-two family members including 17 cataract patients in the Chinese family were analyzed clinically. All family members were genotyped with 382 microsatellite markers that provide genome-wide coverage every 10 cM. Linkage analysis was performed to identify the chromosomal location of the infantile cataract gene in the family. Candidate genes were studied by direct DNA sequence analysis. RESULTS: Genome-wide linkage analysis provided evidence for a genetic locus for infantile cataract on chromosome 20p12.2-20p11.23. The maximum LOD score was 5.15 for marker D20S471 at a recombination fraction of 0. Fine mapping defined the cataract gene within a 7.4 Mb interval between markers D20S915 and D20S912. No mutation was detected in potential candidate genes, BFSP1 and CHMP4B. CONCLUSIONS: Our results suggest that there is a new gene for infantile cataract on chromosome 20p12.2-p11.23. Our results suggest that new genes for infantile cataract could be found through further study of candidate genes at the 20q locus, which may provide insights into the pathogenic mechanisms of cataracts.


Assuntos
Povo Asiático/genética , Catarata/congênito , Catarata/genética , Cromossomos Humanos Par 20/genética , Genes Dominantes/genética , Adolescente , Adulto , Criança , China , Opacidade da Córnea , Família , Feminino , Humanos , Escore Lod , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo
19.
Zhonghua Yan Ke Za Zhi ; 44(6): 529-33, 2008 Jun.
Artigo em Zh | MEDLINE | ID: mdl-19035245

RESUMO

OBJECTIVE: Mapping the mutation gene for a Chinese family with autosomal dominant cataract. METHODS: It was a retrospective study. Thirty-two individuals in this family, including fifteen patients, eight normal siblings and nine spouses, were investigated and 8 ml blood was collected from each member under informed consent. Genomic DNA of all 29 members was isolated by standard protocol. A genome wide scan was performed after PCR amplification for microsatellite makers on autosomal chromosomes. LOD score was calculated by Linkage 5. 1 and GeneHunter software. RESULTS: Positive Lod score were obtained in 10 microsatellite makers (D20S186, D20S163, D20S915, D20S152, D20S98, D20S904, D20S875, D20S112, D20S1140, D20S432) on chromosome 20q, and the maximum LOD score with D20S904 was 6.02. CONCLUSIONS: Haplotype construction and multipoint analysis mapped the mutation gene in this inherited cataract family to the chromosome 20p12. 1-20p11.23 region between D20S186 and D20S912, which is an approximately 5.47 centimorgan length. This is the second congenital cataract locus linked to chromosome 20q.


Assuntos
Catarata/genética , Cromossomos Humanos Par 20 , Mutação , Povo Asiático/genética , Catarata/congênito , Catarata/patologia , Mapeamento Cromossômico , Feminino , Haplótipos , Humanos , Repetições de Microssatélites , Linhagem , Estudos Retrospectivos
20.
Artigo em Inglês | MEDLINE | ID: mdl-29406027

RESUMO

A number of poisoning and suicide cases involving formamidine pesticides have been reported, thus developing a rapid and low cost determination method is crucial. In this work, a rapid, sensitive and low-cost method for the simultaneous determination of formamidine pesticides (amitraz, chlordimeform, formetanate) and their main metabolites, N-(2,4-dimethylphenyl)-N-methyl-formamidine, 2,4-dimethylformamidine, 2,4-dimethylaniline, 4-chloro-2-methylaniline and 3-hydroxyacetanilide in human blood by high-performance liquid chromatography with tandem mass spectrometry is developed. The application of columns with core-shell particles significantly reduced the analysis time. Very low LODs (0.01-0.04 µg L-1) were obtained for formamidine pesticides and their metabolites. The method was successfully applied to the analysis of human blood samples from a real forensic case. The significantly reduced analysis time, high sensitivity and low cost are the primary advantages of the developed method. This methodology provides important value for sensitive and rapid determination of residue pesticides and metabolites, study of residue pesticides behavior in human body, as well as application in real forensic cases.


Assuntos
Amidinas/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Adulto , Amidinas/intoxicação , Criança , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Resíduos de Praguicidas/sangue , Reprodutibilidade dos Testes , Cloreto de Sódio
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