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1.
Biochem Biophys Res Commun ; 690: 149257, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38016245

RESUMO

BACKGROUND: Noise is an important environmental stressor in the industrialized world and has received increasing attention in recent years. Although epidemiological research has extensively demonstrated the relationship between noise and cognitive impairment, the specific molecular mechanisms and targets remain to be fully explored and understood. METHODS: To address this issue, 5-month-old C57BL/6 mice were divided into two groups, with one group exposed to white noise at 98 dB. The effects of noise on cognition in mice were investigated through molecular biology and behavioral experiments. Subsequently, transcriptomic sequencing of the hippocampus in both groups of mice was performed and enrichment analysis of differentially expressed genes (DEGs) was conducted using KEGG and GO databases. Furthermore, LASSO analysis was used to further narrow down the relevant DEGs, followed by enrichment analysis of these genes using KEGG and GO databases. The DEGs were further validated by rt-qPCR. RESULTS: Following noise exposure, the hippocampus levels of inflammation-related factors increased, the phosphorylation of Tau protein increased, the postsynaptic density protein decreased, the number of Nissl bodies decreased, and cell shrinkage in the hippocampus increased. Moreover, the behavioral experiments manifest characteristics indicative of a decline in cognitive.A total of 472 DEGs were identified through transcriptomic analysis, and seven relevant genes were screened by the LASSO algorithm, which were further validated by PCR to confirm their consistency with the omics results. CONCLUSION: In conclusion, noise exposure affects cognitive function in mice through multiple pathways, and the omics results provide new evidence for the cognitive impairment induced by noise exposure.


Assuntos
Disfunção Cognitiva , Perfilação da Expressão Gênica , Camundongos , Animais , Camundongos Endogâmicos C57BL , Hipocampo/metabolismo , Cognição
2.
Funct Integr Genomics ; 23(2): 170, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37209314

RESUMO

As a toxic heavy metal, cadmium (Cd) is one of the principal pollutants influencing rice productivity and food security. Despite several studies, the underlying mechanism of Cd response in plants remains largely unclear. Dehydrins are part of the late embryogenesis abundant (LEA) family which protect plants against abiotic stresses. In this study, a Cd-responsive LEA gene, OsDHN2, was functionally characterized. The chromosome localization results indicated that OsDHN2 was located on chromosome 2 of rice. Meanwhile, cis-acting elements, such as MBS (MYB binding site involved in drought-inducibility), ARE (anaerobic induction), and ABRE (abscisic acid), were present in the OsDHN2 promoter region. Expression pattern analysis also showed that OsDHN2 expression was induced in both roots and shoots under Cd stress. Overexpression of OsDHN2 improved Cd tolerance and reduced Cd concentration in yeast. Moreover, increased expression levels of SOD1, CTA1, GSH1, or CTT1 were found in transgenic yeast under Cd stress, suggesting the increased antioxidant enzymatic activities. These results suggested that OsDHN2 is a Cd-responsive gene that has the potential to improve resistance to Cd in rice.


Assuntos
Cádmio , Oryza , Cádmio/toxicidade , Cádmio/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Oryza/genética , Oryza/metabolismo , Biologia Computacional , Regulação da Expressão Gênica de Plantas
3.
Biochem Biophys Res Commun ; 681: 283-290, 2023 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-37801777

RESUMO

In recent years, it has become an acknowledged fact that noise exposure can lead to cognitive impairments, and researchers have shown increasing interest in this area. However, the detrimental impact of noise exposure on Alzheimer's disease (AD) animal models might be considerably greater than on ordinary model mice, yet the mechanisms by which noise exposure affects the hippocampus in these models have been scarcely investigated. This study we used 4D Label-free proteomics to identify distinctive differentially expressed proteins in the hippocampus of AD model mice following noise exposure. Among these proteins, the presence of Cathepsin S(CTSS) cannot be disregarded. Utilizing experimental techniques such as Western blot, immunofluorescence, and rt-qPCR, we confirmed the expression of CTSS in the hippocampus of APP/PS1 mice after noise exposure. Additionally, we examined downstream molecules including P53,BCL-2, BAX, and CASPASE3 using KEGG pathway analysis. The results indicated an elevation in CTSS expression, a reduction in the anti-apoptotic gene BCL-2, and an increase in the expression of BAX and cleaved CASPASE3. Based on these findings, we hypothesize that noise exposure potentially heightens apoptosis within the hippocampus through upregulating CTSS expression, subsequently posing a threat to AD model animals.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Regulação para Cima , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Hipocampo/metabolismo , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Camundongos Transgênicos , Modelos Animais de Doenças , Precursor de Proteína beta-Amiloide/metabolismo
4.
Biochem Biophys Res Commun ; 687: 149172, 2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-37931421

RESUMO

OBJECTIVE: The study aimed to observe the effects of noise exposure on the pericytes of the cochlear stria vascularis (SV) in mice and to investigate its molecular mechanism. METHOD: Male C57BL/6J mice aged 6-8 weeks were used as the subjects. Auditory Brainstem Response (ABR) was used to assess hearing loss. Hematoxylin and Eosin (HE) staining was conducted to observe morphological alterations in the SV. Immunofluorescence combined with transmission electron microscopy (TEM) was used to scrutinize changes in pericytes following acoustic injury. Western blotting (WB) was used to assess the expression variations of the migration-related protein Osteopontin (OPN). Evans Blue assay was performed to evaluate the permeability of the blood labyrinth barrier (BLB). 4-Hydroxynonenal (4-HNE) staining, in conjunction with measurements of Superoxide Dismutase (SOD), Malondialdehyde (MDA), and Catalase (CAT) content, was used to ascertain whether oxidative stress injury occurred in the SV. WB, combined with immunofluorescence, was used to examine alterations in the expression of proliferator-activated receptor-gamma coactivator 1α (PGC-1α) in the SV and pericytes. RESULTS: Noise exposure resulted in permanent hearing loss in C57BL/6J mice, accompanied by SV swelling, migration of pericytes from their vascular attachments, BLB leakage, elevated oxidative stress levels in the SV, and reduced expression of PGC-1α on both the SV and migrating pericytes. CONCLUSION: Noise exposure may potentially increase oxidative stress levels in the SV, downregulate the expression levels of PGC-1α, promote pericytes migration, and subsequently lead to an elevation in BLB permeability.


Assuntos
Surdez , Orelha Interna , Perda Auditiva Provocada por Ruído , Animais , Humanos , Masculino , Camundongos , Cóclea/metabolismo , Surdez/metabolismo , Orelha Interna/metabolismo , Perda Auditiva Provocada por Ruído/metabolismo , Camundongos Endogâmicos C57BL , Pericitos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo
5.
J Comput Sci Technol ; 37(6): 1444-1463, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36594007

RESUMO

Friend recommendation plays a key role in promoting user experience in online social networks (OSNs). However, existing studies usually neglect users' fine-grained interest as well as the evolving feature of interest, which may cause unsuitable recommendation. In particular, some OSNs, such as the online learning community, even have little work on friend recommendation. To this end, we strive to improve friend recommendation with fine-grained evolving interest in this paper. We take the online learning community as an application scenario, which is a special type of OSNs for people to learn courses online. Learning partners can help improve learners' learning effect and improve the attractiveness of platforms. We propose a learning partner recommendation framework based on the evolution of fine-grained learning interest (LPRF-E for short). We extract a sequence of learning interest tags that changes over time. Then, we explore the time feature to predict evolving learning interest. Next, we recommend learning partners by fine-grained interest similarity. We also refine the learning partner recommendation framework with users' social influence (denoted as LPRF-F for differentiation). Extensive experiments on two real datasets crawled from Chinese University MOOC and Douban Book validate that the proposed LPRF-E and LPRF-F models achieve a high accuracy (i.e., approximate 50% improvements on the precision and the recall) and can recommend learning partners with high quality (e.g., more experienced and helpful). Supplementary Information: The online version contains supplementary material available at 10.1007/s11390-021-2124-z.

6.
Molecules ; 25(2)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963527

RESUMO

Aromatic heterocycles are ubiquitous building blocks in bioactive natural products, pharmaceutical and agrochemical industries. Accordingly, the carborane-fused heterocycles would be potential candidates in drug discovery, nanomaterials, metallacarboranes, as well as photoluminescent materials. In recent years, the transition metal catalyzed B-H activation has been proved to be an effective protocol for selective functionalization of B-H bond of o-carboranes, which has been further extended for the synthesis of polyhedral borane cluster-fused heterocycles via cascade B-H functionalization/annulation process. This article summarizes the recent progress in construction of polyhedral borane cluster-fused heterocycles via B-H activation.


Assuntos
Boranos/química , Compostos Heterocíclicos/síntese química , Elementos de Transição/química , Catálise , Compostos Heterocíclicos/química , Hidrogênio/química , Estrutura Molecular
7.
Appl Environ Microbiol ; 85(24)2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31604771

RESUMO

Many Gram-negative bacteria employ N-acylhomoserine lactones (AHLs) as quorum-sensing (QS) signal molecules to regulate virulence expression in a density-dependent manner. Quorum quenching (QQ) via enzymatic inactivation of AHLs is a promising strategy to reduce bacterial infections and drug resistance. Herein, a thermostable AHL lactonase (AidB), which could degrade different AHLs, with or without a substitution of carbonyl or hydroxyl at the C-3 position, was identified from the soil bacterium Bosea sp. strain F3-2. Ultrahigh-performance liquid chromatography analysis demonstrated that AidB is an AHL lactonase that hydrolyzes the ester bond of the homoserine lactone (HSL) ring. AidB was thermostable in the range 30 to 80°C and showed maximum activity after preincubation at 60°C for 30 min. The optimum temperature of AidB was 60°C, and the enzyme could be stably stored in double-distilled water (ddH2O) at 4°C or room temperature. AidB homologs were found only in Rhizobiales and Rhodospirillales of the Alphaproteobacteria AidB from Agrobacterium tumefaciens and AidB from Rhizobium multihospitium (with amino acid identities of 50.6% and 52.8% to AidB, respectively) also showed thermostable AHL degradation activity. When introduced into bacteria, plasmid-expressed AidB attenuated pyocyanin production by Pseudomonas aeruginosa PAO1 and the pathogenicity of Pectobacterium carotovorum subsp. carotovorum Z3-3, suggesting that AidB is a potential therapeutic agent by degrading AHLs.IMPORTANCE A quorum-sensing system using AHLs as the signal in many bacterial pathogens is a critical virulence regulator and an attractive target for anti-infective drugs. In this work, we identified a novel AHL lactonase, AidB, from a soil bacterial strain, Bosea sp. F3-2. The expression of aidB reduced the production of AHL signals and QS-dependent virulence factors in Pseudomonas aeruginosa and Pectobacterium carotovorum The homologs of AidB with AHL-degrading activities were found only in several genera belonging to the Alphaproteobacteria Remarkably, AidB is a thermostable enzyme that retained its catalytic activity after treatment at 80°C for 30 min and exhibits reliable storage stability at both 4°C and room temperature. These properties might make it more suitable for practical application.


Assuntos
Bradyrhizobiaceae/enzimologia , Bradyrhizobiaceae/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , 4-Butirolactona/análogos & derivados , Acil-Butirolactonas/metabolismo , Agrobacterium tumefaciens/metabolismo , Sequência de Aminoácidos , Bactérias/metabolismo , Proteínas de Bactérias , Bradyrhizobiaceae/genética , Estabilidade Enzimática , Pectobacterium carotovorum/metabolismo , Pseudomonas aeruginosa/metabolismo , Piocianina/metabolismo , Percepção de Quorum , Virulência , Fatores de Virulência/metabolismo , Sequenciamento Completo do Genoma
8.
Ophthalmic Physiol Opt ; 39(6): 451-458, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31696541

RESUMO

PURPOSE: To determine the differences in mean ocular dimensions between urban and rural children and identify possible influencing factors. METHODS: This work uses previously published data from the Shandong Children Eye Study, which was based on a random cluster sampling applied to a cross-sectional school-based study design in the rural Guanxian County and Weihai city. All children underwent auto-refractometry and biometry under cycloplegia. RESULTS: The study included 3290 children (aged 9.35 ± 2.93 years), consisting of 888 pairs of boys and 757 pairs of girls matched by sex, age and refractive error (each pair matching one child from urban cohort with one from the rural cohort). Overall urban children were significantly taller and heavier than rural children (t-test; p < 0.001), which was confirmed for all age groups for weight. Urban ocular axial lengths were significantly longer by 0.23 mm compared to the rural population (t-test; p < 0.001), mostly in younger children and boys. Meanwhile, corneal curvatures were flatter in the urban cohort by 0.08 mm (p < 0.001). This association of axial length with urban vs rural region was reduced in magnitude by 69.7% after accounting for height. CONCLUSIONS: For the same, matched refractive error, children from urban regions had significantly longer eyes and flatter corneal curvature than rural children. Since corneal curvature is defined during the first 2 years of life, early environmental factors may be the source of these differences in ocular dimensions.


Assuntos
Biometria/métodos , Córnea/fisiopatologia , Refração Ocular/fisiologia , Erros de Refração/diagnóstico , População Rural , População Urbana , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Córnea/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Erros de Refração/epidemiologia , Erros de Refração/fisiopatologia
9.
Yi Chuan ; 41(10): 919-927, 2019 Oct 20.
Artigo em Zh | MEDLINE | ID: mdl-31624054

RESUMO

Fibrillin-2 (FBN2) is an important component of microfibers which are involved in the formation of elastic fibers in connective tissue throughout the human body. Hereditary connective tissue diseases may result from genetic mutations of FBN2 causing heterogeneity of fibrin. Genetic mutations of FBN2 are associated with a variety of hereditary connective tissue diseases including Congenital Contractural Arachnodactyl (CCA), Macular Degeneration (MD), and myopathy. Studies have shown that the FBN2 gene is recognized as the only pathogenic gene related to CCA and that CCA patients have different clinical presentations depending on the identified genetic mutations at different FBN2 sites. In this review, we summarize the roles of FBN2, its mutations and impact on the physiological and pathological processes of many hereditary connective tissue diseases. We include brief descriptions of clinical manifestations of these diseases providing a basis for further exploration of the specific molecular mechanism of FBN2 gene mutation pathogenesis which provides a theoretical basis for the therapy and medications for refractory diseases caused by FBN2 gene mutation.


Assuntos
Doenças do Tecido Conjuntivo/genética , Fibrilina-2/genética , Humanos , Mutação
10.
Biol Pharm Bull ; 41(9): 1430-1439, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29984733

RESUMO

Tribulus terrestris L. (Zygophyllaceae) (TT) is usually used as a cardiotonic, diuretic, and aphrodisiac, as well as for herbal post-stroke rehabilitation in traditional Chinese medicine. However, little is known about the renoprotective effects of TT on obesity-related glomerulopathy (ORG). In this study, 340 monomeric compounds were identified from TT extracts obtained with ethyl acetate combined with 50% methanol. In vitro, IC50 of TT was 912.01 mg/L, and the appropriate concentration of TT against oxidized-low density lipoprotein (ox-LDL) induced human renal glomerular endothelial cells (HRGECs) was 4 mg/L. TT significantly increased the viability (63.2%) and migration (2.33-fold increase) of HRGECs. ORG model rats were induced by a chronic high-fat diet (45%) for 20 weeks and were then treated with TT extract (2.8 g/kg/d) for 8 weeks. Subsequently, the kidneys were removed and their differentially expressed protein profile was identified using two-dimensional electrophoresis coupled with matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF)-TOF MS. Molecular categorization and functional analysis of bioinformatic annotation suggested that excessive energy metabolism, decreased response to stress and low immunity were the potential etiologies of ORG. After TT administration for 8 weeks, body weight, blood pressure, serum cystatin C and cholesterol were decreased. Additionally, TT significantly enhanced the resistance of rats to ORG, decreased energy consumption and the hemorrhagic tendency, and improved the response to acute phase reactants and immunity. In conclusion, TT may play a protective role against ORG in rats.


Assuntos
Glomerulonefrite Membranosa/tratamento farmacológico , Rim/efeitos dos fármacos , Obesidade/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Proteômica/métodos , Tribulus , Animais , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Frutas , Glomerulonefrite Membranosa/metabolismo , Humanos , Rim/metabolismo , Rim/patologia , Masculino , Obesidade/metabolismo , Obesidade/patologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Resultado do Tratamento
11.
Med Sci Monit ; 24: 9504-9508, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30596382

RESUMO

BACKGROUND The aim of this study was to detect the expression of fork-head box D3 (FOXD3) and investigate its diagnostic value in patients with non-small cell lung cancer (NSCLC). MATERIAL AND METHODS The relative expression of FOXD3 at mRNA and protein levels was determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting analysis, respectively. Chi-square test was used to explore the relevance of FOXD3 expression with clinical features of NSCLC patients. A receiver operating characteristic (ROC) curve was built to estimate the diagnostic value of FOXD3 in distinguishing NSCLC patients from healthy controls. RESULTS Serum FOXD3 expression was weakly expressed in NSCLC patients compared to the controls at mRNA and protein levels (P<0.001) and low FOXD3 expression was positively correlated with TNM stage, lymph node metastasis, and differentiation. The ROC curve indicated that FOXD3 acts as a diagnostic bio-marker for NSCLC patients, with an AUC of 0.826 corresponding to a sensitivity of 77.1% and a specificity of 74.6%, and an optimal cutoff point of 2.38. CONCLUSIONS Decreased expression of serum FOXD3 was observed in NSCLC patients, and it was found to be a potential molecular marker for the diagnosis of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Fatores de Transcrição Forkhead/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Adulto , Idoso , Área Sob a Curva , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/patologia , Fatores de Transcrição Forkhead/sangue , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , Curva ROC
12.
Bioorg Med Chem ; 25(16): 4277-4284, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28662961

RESUMO

To explore the structure-activity relationships of flavanonols on the inhibition of nitric oxide (NO) production in RAW 264.7 cells, we have prepared a series of synthetic flavanonols. In our previous study, the 2',3'-dihydroxyphenyl substructure was found to be the most potent B ring substructure among the flavanonols having 3,5,7-trihydroxychroman-4-one as the A/C ring. In this study, we examined the effect of diverse substitutions on the A ring of the 2-(2,3-dihydroxyphenyl)-3-hydroxychroman-4-one scaffold, i.e., by fixing the B ring to the 2',3'-dihydroxyphenyl substructure. Eighteen stereoisomers and 4 racemic mixtures were prepared, and their inhibitory potency on NO production in RAW 264.7 cells was tested. We observed higher inhibitory activity in the (2R,3R) stereoisomers than in the (2S,3S) stereoisomers. The presence of a hydroxy or a methoxy group at the 7-postiion enhanced the inhibitory potency, and the additional substitutions at the 6- or 8-position in the A ring increased potency and stereospecificity. A representative compound, (2R,3R)-2',3',7,8-tetrahydroxyflavanonol 5e, had an IC50 value of 17µM, whereas its (2S,3S) stereoisomer did not inhibit NO production at all at a concentration of 100µM. In this study, it was necessary to determine the absolute configuration of the stereoisomers of the synthesized flavanonols that carry methoxy substitutions in the A ring. The procedure to determine their absolute configuration by the CD excitation chirality method is also discussed.


Assuntos
Flavanonas/farmacologia , Macrófagos/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Flavanonas/síntese química , Flavanonas/química , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Células RAW 264.7 , Estereoisomerismo , Relação Estrutura-Atividade
13.
Bioorg Med Chem ; 25(2): 779-788, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27955927

RESUMO

We isolated flavonoids from herbal specimens from the Tibetan region (Sophora yunnanensis and Rhodiola sacra) that suppress nitric oxide (NO) production in macrophages stimulated by lipopolysaccharide and interferon-γ. The isolated flavonoids carry symmetric substitutions in the B ring (R3'=R5'). We analyzed the quantitative structure-activity relationship of the inhibitory activity by comparative molecular field analysis (CoMFA) using this series of flavonoids. Use of flavonoids with symmetrical substitutions in the B ring made it simpler to align molecules because it was not necessary to consider a huge number of combinations due to the B-ring conformation. The CoMFA model, whose cross-validated q2 value was 0.705, suggested the existence of a hydroxy group at the 5-position, the choice of the A/C-ring scaffold (chromane or chromene) and electrostatic field around the B ring are important for NO inhibitory activity. Flavonoids synthesized based on the CoMFA model exhibited significant inhibitory potential against NO production, validating the predictive capability of the CoMFA model.


Assuntos
Produtos Biológicos/farmacologia , Flavonoides/farmacologia , Óxido Nítrico/antagonistas & inibidores , Animais , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Relação Dose-Resposta a Droga , Flavonoides/química , Flavonoides/isolamento & purificação , Camundongos , Modelos Moleculares , Estrutura Molecular , Óxido Nítrico/biossíntese , Células RAW 264.7 , Rhodiola/química , Sophora/química , Relação Estrutura-Atividade
14.
Retina ; 37(8): 1428-1440, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28085774

RESUMO

BACKGROUND: The process of emmetropization is the adjustment of the length of the optical axis to the given optical properties of the cornea and lens after the end of the second year of life. Since its underlying mechanisms have not been fully explored yet, we reviewed findings available in the literature to discuss its potential etiology and the mechanism of myopization as an overshooting of emmetropization. METHODS: Literature review. RESULTS: The process of emmetropization occurs by axial elongation. Up to the end of the second year of life, the eye grows spherically by active increase in scleral volume. Axial elongation in the process of emmetropization is associated with thinning of the retina and reduced density of retinal pigment epithelium cells (RPE) in the retro-equatorial region, and with thinning more of the choroid than of the sclera, starting at the equator and being most marked at the posterior pole. In contrast, retinal thickness and RPE density in the macular region and thickness of Bruch's membrane (BM) in any region are independent of axial length. CONCLUSIONS: It led to the hypothesis that axial elongation occurs by production of BM in the retro-equatorial region leading to a decreased RPE density and retinal thinning in that region and a more tube-like than spherical enlargement of the globe, without compromise in the density of the macular RPE cells and in macular retinal thickness. The increased disc-fovea distance in axially myopic eyes is caused by the development and enlargement of parapapillary, BM free, gamma zone while the length of macular BM, and indirectly macular RPE cell density and macular retinal thickness, remain constant. The target tissue for medical modification of emmetropization/myopization may be the RPE, producing and elongating BM in the retro-equatorial region.


Assuntos
Comprimento Axial do Olho/patologia , Lâmina Basilar da Corioide/patologia , Miopia/patologia , Esclera/patologia , Progressão da Doença , Humanos , Macula Lutea/patologia
15.
Clin Exp Ophthalmol ; 45(2): 112-119, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27527118

RESUMO

BACKGROUND: To assess the corneal diameter and its associations in children. DESIGN: Cross-sectional school-based study. PARTICIPANTS: Six thousand twenty-six children aged 4-18 years were included in the Shandong Children Eye Study. METHODS: Horizontal corneal diameter was measured by laser interferometry-based ocular biometry. MAIN OUTCOME MEASURES: Horizontal corneal diameter. RESULTS: Corneal diameter measurements were available for 5970 (99.1%) children. In multivariate analysis, larger horizontal corneal diameter (mean: 12.02 ± 0.38 mm; range: 10.1-15.0 mm) was associated with longer corneal curvature radius longer axial length, male gender, younger maternal age, rural region of habitation and lower intraocular pressure measurements. Higher prevalence of abnormally large corneas (macrocorneas; horizontal diameter ≥ 12.76 mm; mean value +2 × standard deviations; mean: 2.6%; 95% CI: 2.2, 3.0) was associated with longer corneal curvature radius, longer axial length, younger maternal age and male gender. Higher prevalence of abnormally small corneas (horizontal diameter ≤ 11.24mm; mean value -2 × standard deviations; mean: 2.4%; 95% CI: 2.0, 2.8) was correlated with shorter corneal curvature radius, shorter axial length and urban region of habitation. Neither abnormally large nor small corneas were correlated with time spent indoors/outdoors. CONCLUSIONS: In 4 to 18-year-old children, larger corneal diameter was associated most strongly with flatter corneal curvature, followed by longer axial length and male gender. Corneal diameter was independent of age beyond an age of 4 years. Abnormally large and abnormally small corneas may be defined as being ≥12.76 and ≤11.24 mm in diameter, respectively. Corneal diameter was not correlated with time spent indoors/outdoors.


Assuntos
Comprimento Axial do Olho , Córnea/anatomia & histologia , Miopia/epidemiologia , Refração Ocular/fisiologia , População Rural , População Urbana , Adolescente , Biometria , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Interferometria , Pressão Intraocular , Masculino , Prevalência , Instituições Acadêmicas
16.
Tumour Biol ; 37(6): 8375-82, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26733164

RESUMO

ATP-binding cassette E1 (ABCE1) is a member of the ATP-binding cassette transporters and regulates a broad range of biological functions including viral infection, cell proliferation, and anti-apoptosis. We have previously shown that ABCE1 is a prognostic indicator for lung cancer, although the underlying mechanisms remain unclear. To investigate whether the ABCE1 gene contributes to the malignancy of lung tumors, we introduced ABCE1 into LTEP-a-2 lung adenocarcinoma cells. Ectopic ABCE1 expression promoted clonogenicity and anchorage-independent growth of LTEP-a-2 cells, while in a mouse xenograft tumor model, it had an augmentative effect on tumor growth and metastasis and reduced the expression of the tumor-suppressor gene growth arrest and DNA damage-inducible 45α (GADD45α). Moreover, apoptosis was not significantly influenced by ABCE1 in vitro. In summary, we have provided evidence that ABCE1 plays an essential role in the progression and metastasis of lung cancers and may represent a valuable therapeutic target for the management of lung tumor.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Animais , Apoptose/genética , Western Blotting , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/fisiologia , Xenoenxertos , Humanos , Gelo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Metástase Neoplásica/genética , Proteínas Nucleares/genética , Reação em Cadeia da Polimerase em Tempo Real
17.
Bioorg Med Chem ; 23(21): 6922-9, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26481151

RESUMO

To explore the structure-activity relationships on the inhibitory activity of flavanonols against nitric oxide (NO) production in inflammatory cells, we synthesized 19 flavanonols which shared a common 3,5,7-trihydroxychroman scaffold. A range of substitutions was included in the B ring in order to investigate the structure-activity relationship. We also succeeded in isolating stereoisomers from 16 of the flavanonols using chiral column chromatography. The inhibitory effects of these compounds on NO production were examined in RAW 264.7 cells (a murine macrophage-like cell line), which were activated by lipopolysaccharide (LPS). We only observed inhibitory activity against NO production in (2R,3R) stereoisomers, while the inhibitory activities of (2S,3S) stereoisomers were significantly weaker. We also evaluated the free radical scavenging potential of the flavanonols using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Each stereoisomer indicated the equivalent DPPH scavenging potential as expected. The radical scavenging activity was not correlated with the inhibitory activity against NO. The inhibition of NO production by flavanonols is stereospecific and cannot simply be explained by their radical scavenging activity. We propose the possible existence of a 'target' molecule for flavanonols which is involved in the production and/or regulation of NO in RAW 264.7 cells.


Assuntos
Cromanos/química , Sequestradores de Radicais Livres/química , Óxido Nítrico/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromanos/síntese química , Cromanos/farmacologia , Sequestradores de Radicais Livres/síntese química , Sequestradores de Radicais Livres/farmacologia , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
18.
ChemistryOpen ; 13(7): e202300286, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38200654

RESUMO

In recent years, with the global warming getting worse and increasing demand for energy, countries around the world are trying to develop new energy storage technologies to solve this problem. Currently, potassium-ion batteries (PIBs) have attracted tremendous attention from researchers as low-cost and high-performance energy storage devices. However, due to the huge ionic radius of K+, PIBs face significant volume expansion during cycling, which can easily lead to the collapse of electrode structures. In addition, the poor diffusion kinetics of K+ seriously affect the electrochemical performance of the battery. Carbon nanofibers (CNFs)-based materials (including CNFs, metal/CNFs composites, chalcogenide/CNFs composites, and other CNFs-based materials) are widely used as PIBs electrode anode materials due to their three-dimensional conductive network, heteroatom doping and excellent mechanical properties. This review discusses in detail the research progress of CNFs-based materials in PIBs, including material preparation, structural design, and performance optimization. On this basis, this article explores the key issues faced by CNFs-based materials and future development directions, and proposes improvement suggestions for providing new ideas for the development of CNFs-based materials.

19.
Photochem Photobiol ; 100(2): 380-392, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38041414

RESUMO

We have employed the highly accurate multistate complete active space second-order perturbation theory (MS-CASPT2) method to investigate the photoinduced excited state relaxation properties of one unnatural base, namely Z. Upon excitation to the S2 state of Z, the internal conversion to the S1 state would be dominant. From the S1 state, two intersystem crossing paths leading to the T2 and T1 states and one internal conversion path to the S0 state are possible. However, considering the large barrier to access the S1 /S0 conical intersection and the strong spin-orbit coupling between S1 and T2 states (>40 cm-1 ), the intersystem crossing to the triplet manifolds is predicted to be more preferred. Arriving at the T2 state, the internal conversion to the T1 state and the intersystem crossing back to the S1 state are both possible considering the S1 /T2 /T1 three-state intersection near the T2 minimum. Upon arrival at the T1 state, the deactivation to S0 can be efficient after overcoming a small barrier to access T1 /S0 crossing point, where the spin-orbit coupling (SOC) is as large as 39.7 cm-1 . Our present work not only provides in-depth insights into the photoinduced process of unnatural base Z, but can also help the future design of novel unnatural bases with better photostability.

20.
World J Gastrointest Oncol ; 16(1): 182-196, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38292848

RESUMO

BACKGROUND: Colorectal cancer (CRC) plays a significant role in morbidity, mortality, and economic cost in the Belt and Road Initiative ("B and R") countries. In addition, these countries have a substantial consumption of processed meat. However, the burden and trend of CRC in relation to the consumption of a diet high in processed meat (DHPM-CRC) in these "B and R" countries remain unknown. AIM: To analyze the burden and trend of DHPM-CRC in the "B and R" countries from 1990 to 2019. METHODS: We used the 2019 Global Burden of Disease Study to collate information regarding the burden of DHPM-CRC. Numbers and age-standardized rates (ASRs) of deaths along with the disability-adjusted life years (DALYs) were determined among the "B and R" countries in 1990 and 2019. Using joinpoint regression analysis, the average annual percent change (AAPC) was used to analyze the temporal trends of age-standardized DALYs rate (ASDALR) from 1990 to 2019 and in the final decade (2010-2019). RESULTS: We found geographical differences in the burden of DHPM-CRC among "B and R" countries, with the three highest-ranking countries being the Russian Federation, China, and Ukraine in 1990, and China, the Russian Federation, and Poland in 2019. The burden of DHPM-CRC generally increased in most member countries from 1990 to 2019 (all P < 0.05). The absolute number of deaths and DALYs in DHPM-CRC were 3151.15 [95% uncertainty interval (UI) 665.74-5696.64] and 83249.31 (95%UI 15628.64-151956.31) in China in 2019. However, the number of deaths (2627.57-2528.51) and DALYs (65867.39-55378.65) for DHPM-CRC in the Russian Federation has declined. The fastest increase in ASDALR for DHPM-CRC was observed in Vietnam, Southeast Asia, with an AAPC value of 3.90% [95% confidence interval (CI): 3.63%-4.16%], whereas the fastest decline was observed in Kyrgyzstan, Central Asia, with an AAPC value of -2.05% (95% CI: -2.37% to -1.73%). A substantial upward trend in ASR of mortality, years lived with disability, years of life lost, and DALYs from DHPM-CRC changes in 1990-2019 and the final decade (2010-2019) for most Maritime Silk Route members in East Asia, South Asia, Southeast Asia, North Africa, and the Middle East, as well as Central Europe, while those of the most Land Silk Route members in Central Asia and Eastern Europe have decreased markedly (all P < 0.05). The ASDALR for DHPM-CRC increased more in males than in females (all P < 0.05). For those aged 50-74 years, the ASDALR for DHPM-CRC in 40 members exhibited an increasing trend, except for 20 members, including 7 members in Central Asia, Maldives, and 12 high or high-middle social development index (SDI) members in other regions (all P < 0.05). CONCLUSION: The burden of DHPM-CRC varies substantially across "B and R" countries and threatens public health. Relevant evidence-based policies and interventions tailored to the different trends of countries in SDIs or Silk Routes should be adopted to reduce the future burden of CRC in "B and R" countries via extensive collaboration.

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