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1.
Cell Mol Neurobiol ; 43(7): 3161-3178, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37338781

RESUMO

Glaucoma is a group of diseases characterized by the degeneration of retinal ganglion cells (RGCs) and progressive, irreversible vision loss. High intraocular pressure (IOP) heightens the likelihood of glaucoma and correlates with RGC loss. While the current glaucoma therapy prioritizes lower the IOP; however, RGC, and visual loss may persist even when the IOP is well-controlled. As such, discovering and creating IOP-independent neuroprotective strategies for safeguard RGCs is crucial for glaucoma management. Investigating and clarifying the mechanism behind RGC death to counteract its effects is a promising direction for glaucoma control. Empirical studies of glaucoma reveal the role of multiple regulated cell death (RCD) pathways in RGC death. This review delineates the RCD of RGCs following IOP elevation and optic nerve damage and discusses the substantial benefits of mitigating RCD in RGCs in preserving visual function.


Assuntos
Glaucoma , Morte Celular Regulada , Animais , Células Ganglionares da Retina/metabolismo , Pressão Intraocular , Glaucoma/terapia , Glaucoma/metabolismo , Neuroproteção , Modelos Animais de Doenças
2.
Int J Biol Sci ; 19(2): 658-674, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36632450

RESUMO

The discovery of the necroptosis, a form of regulated necrosis that is mediated by receptor-interacting protein kinase 1 (RIPK1), RIPK3, and mixed-lineage kinase domain-like pseudokinase (MLKL), represents a major breakthrough that has dramatically altered the conception of necrosis - traditionally thought of as uncontrolled cell death - in various human diseases. Retinal cell death is a leading cause of blindness and has been identified in most retinal diseases, e.g., age-related macular degeneration, glaucoma, retinal detachment, retinitis pigmentosa, etc. Increasing evidence demonstrates that retinal degenerative diseases also share a common mechanism in necroptosis. Exacerbated necroptotic cell death hinders the treatment for retinal degenerative diseases. In this review, we highlight recent advances in identifying retinal necroptosis, summarize the underlying mechanisms of necroptosis in retinal degenerative diseases, and discuss potential anti-necroptosis strategies, such as selective inhibitors and chemical agents, for treating retinal degenerative diseases.


Assuntos
Necroptose , Degeneração Retiniana , Humanos , Proteínas Quinases/metabolismo , Necroptose/efeitos dos fármacos , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/patologia
3.
J Magn Reson Imaging ; 58(5): 1590-1602, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36661350

RESUMO

BACKGROUND: Dynamic contrast-enhanced (DCE) MRI and non-mono-exponential model-based diffusion-weighted imaging (NME-DWI) that does not require contrast agent can both characterize breast cancer. However, which technique is superior remains unclear. PURPOSE: To compare the performances of DCE-MRI, NME-DWI and their combination as multiparametric MRI (MP-MRI) in the prediction of breast cancer prognostic biomarkers and molecular subtypes based on radiomics. STUDY TYPE: Prospective. POPULATION: A total of 477 female patients with 483 breast cancers (5-fold cross-validation: training/validation, 80%/20%). FIELD STRENGTH/SEQUENCE: A 3.0 T/DCE-MRI (6 dynamic frames) and NME-DWI (13 b values). ASSESSMENT: After data preprocessing, high-throughput features were extracted from each tumor volume of interest, and optimal features were selected using recursive feature elimination method. To identify ER+ vs. ER-, PR+ vs. PR-, HER2+ vs. HER2-, Ki-67+ vs. Ki-67-, luminal A/B vs. nonluminal A/B, and triple negative (TN) vs. non-TN, the following models were implemented: random forest, adaptive boosting, support vector machine, linear discriminant analysis, and logistic regression. STATISTICAL TESTS: Student's t, chi-square, and Fisher's exact tests were applied on clinical characteristics to confirm whether significant differences exist between different statuses (±) of prognostic biomarkers or molecular subtypes. The model performances were compared between the DCE-MRI, NME-DWI, and MP-MRI datasets using the area under the receiver-operating characteristic curve (AUC) and the DeLong test. P < 0.05 was considered significant. RESULTS: With few exceptions, no significant differences (P = 0.062-0.984) were observed in the AUCs of models for six classification tasks between the DCE-MRI (AUC = 0.62-0.87) and NME-DWI (AUC = 0.62-0.91) datasets, while the model performances on the two imaging datasets were significantly poorer than on the MP-MRI dataset (AUC = 0.68-0.93). Additionally, the random forest and adaptive boosting models (AUC = 0.62-0.93) outperformed other three models (AUC = 0.62-0.90). DATA CONCLUSION: NME-DWI was comparable with DCE-MRI in predictive performance and could be used as an alternative technique. Besides, MP-MRI demonstrated significantly higher AUCs than either DCE-MRI or NME-DWI. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Estudos Prospectivos , Antígeno Ki-67 , Prognóstico , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
4.
Neural Regen Res ; 18(2): 357-363, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35900430

RESUMO

PANoptosis is a newly identified type of regulated cell death that consists of pyroptosis, apoptosis, and necroptosis, which simultaneously occur during the pathophysiological process of infectious and inflammatory diseases. Although our previous literature mining study suggested that PANoptosis might occur in neuronal ischemia/reperfusion injury, little experimental research has been reported on the existence of PANoptosis. In this study, we used in vivo and in vitro retinal neuronal models of ischemia/reperfusion injury to investigate whether PANoptosis-like cell death (simultaneous occurrence of pyroptosis, apoptosis, and necroptosis) exists in retinal neuronal ischemia/reperfusion injury. Our results showed that ischemia/reperfusion injury induced changes in morphological features and protein levels that indicate PANoptosis-like cell death in retinal neurons both in vitro and in vivo. Ischemia/reperfusion injury also significantly upregulated caspase-1, caspase-8, and NLRP3 expression, which are important components of the PANoptosome. These results indicate the existence of PANoptosis-like cell death in ischemia/reperfusion injury of retinal neurons and provide preliminary experimental evidence for future study of this new type of regulated cell death.

5.
Neural Regen Res ; 17(8): 1761-1768, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35017436

RESUMO

Some scholars have recently developed the concept of PANoptosis in the study of infectious diseases where pyroptosis, apoptosis and necroptosis act in consort in a multimeric protein complex, PANoptosome. This allows all the components of PANoptosis to be regulated simultaneously. PANoptosis provides a new way to study the regulation of cell death, in that different types of cell death may be regulated at the same time. To test whether PANoptosis exists in diseases other than infectious diseases, we chose cerebral ischemia/reperfusion injury as the research model, collected articles researching cerebral ischemia/reperfusion from three major databases, obtained the original research data from these articles by bibliometrics, data mining and other methods, then integrated and analyzed these data. We selected papers that investigated at least two of the components of PANoptosis to check its occurrence in ischemia/reperfusion. In the cell model simulating ischemic brain injury, pyroptosis, apoptosis and necroptosis occur together and this phenomenon exists widely in different passage cell lines or primary neurons. Pyroptosis, apoptosis and necroptosis also occurred in rat and mouse models of ischemia/reperfusion injury. This confirms that PANoptosis is observed in ischemic brain injury and indicates that PANoptosis can be a target in the regulation of various central nervous system diseases.

6.
Molecules ; 28(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36615244

RESUMO

Cell death is a fundamental pathophysiological process in human disease. The discovery of necroptosis, a form of regulated necrosis that is induced by the activation of death receptors and formation of necrosome, represents a major breakthrough in the field of cell death in the past decade. Z-DNA-binding protein (ZBP1) is an interferon (IFN)-inducing protein, initially reported as a double-stranded DNA (dsDNA) sensor, which induces an innate inflammatory response. Recently, ZBP1 was identified as an important sensor of necroptosis during virus infection. It connects viral nucleic acid and receptor-interacting protein kinase 3 (RIPK3) via two domains and induces the formation of a necrosome. Recent studies have also reported that ZBP1 induces necroptosis in non-viral infections and mediates necrotic signal transduction by a unique mechanism. This review highlights the discovery of ZBP1 and its novel findings in necroptosis and provides an insight into its critical role in the crosstalk between different types of cell death, which may represent a new therapeutic option.


Assuntos
Necroptose , Necrose , Humanos , Necrose/tratamento farmacológico , Necrose/metabolismo , Viroses/metabolismo
7.
Drug Des Devel Ther ; 15: 4275-4287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34703209

RESUMO

INTRODUCTION: Thyroid cancer is a familiar kind of cancer. Natural products are promising therapeutic approaches in treating thyroid cancer. Triptolide is a diterpenoid epoxide extracted from Tripterygium wilfordii. The mechanism of triptolide in the treatment of thyroid cancer has not been investigated clearly. METHODS: We evaluated triptolide targets and thyroid cancer targets with related databases. The protein-protein interaction (PPI) networks of the triptolide targets and thyroid cancer targets were constructed with Cytoscape software. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of the core PPI network were obtained. Molecular docking analysis was used to evaluated the binding of triptolide with core targets. Furthermore, apoptosis assays, real-time polymerase chain reaction (RT-PCR) and Western blotting were used to evaluate the anticancer functions of triptolide. RESULTS: Triptolide had 34 targets, and thyroid cancer had 210 targets. The core PPI network of merged PPI networks had 164 nodes and 4513 edges. GO and KEGG enrichment analyses showed that triptolide were related to the cell cycle, apoptosis, and inflammatory signaling pathways. Molecular docking analysis showed that triptolide directly reacted with four core targets: cyclin-dependent kinase inhibitor 1A (CDKN1A), c-JUN, RELA, and tumor protein p53 (TP53). CB-Dock analysis indicated that triptolide could stably bind to core targets. Triptolide inhibited the growth but induced apoptosis of thyroid cancer cells. Triptolide increased the mRNA expression of CDKN1A and TP53 but reduced the mRNA expression of c-JUN and RELA, as shown by RT-PCR. Triptolide increased the protein levels of CDKN1A and phospho-p53 but reduced those of phospho-c-JUN and phospho-NF-κB p65, as shown by Western blotting. DISCUSSION: We considered that triptolide could treat thyroid cancer by inhibiting cell proliferation, inducing apoptosis and inhibiting inflammatory pathways such as the NF-κB and MAPK signaling pathways. CDKN1A, c-JUN, RELA, and TP53 were involved in the antithyroid cancer mechanism of triptolide.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Apoptose/efeitos dos fármacos , Diterpenos/farmacologia , Fenantrenos/farmacologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Linhagem Celular Tumoral , Compostos de Epóxi/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , Mapas de Interação de Proteínas , Neoplasias da Glândula Tireoide/patologia
8.
Front Cell Dev Biol ; 9: 809656, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34977045

RESUMO

Stem cell therapies have shown promising therapeutic effects in restoring damaged tissue and promoting functional repair in a wide range of human diseases. Generations of insulin-producing cells and pancreatic progenitors from stem cells are potential therapeutic methods for treating diabetes and diabetes-related diseases. However, accumulated evidence has demonstrated that multiple types of programmed cell death (PCD) existed in stem cells post-transplantation and compromise their therapeutic efficiency, including apoptosis, autophagy, necroptosis, pyroptosis, and ferroptosis. Understanding the molecular mechanisms in PCD during stem cell transplantation and targeting cell death signaling pathways are vital to successful stem cell therapies. In this review, we highlight the research advances in PCD mechanisms that guide the development of multiple strategies to prevent the loss of stem cells and discuss promising implications for improving stem cell therapy in diabetes and diabetes-related diseases.

9.
Huan Jing Ke Xue ; 41(3): 1099-1106, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608610

RESUMO

This study identified the generation and emission nodes of volatile organic compounds (VOCs) in the metal packaging industry, analyzed the VOCs concentration and species from different production processes, and accounted for secondary pollution through the maximum incremental reactivity method and modified fractional aerosol coefficient method. The results indicated that the main VOCs species were benzenes, alcohols, ketones, and esters, and the benzenes and alcohols contributed more in different types of processes and emission nodes, whereas the ketones and esters contributed less. The maximum concentration was 269.08mg·m-3 (n-butanol). Strong correlation was found between the concentrations of the production line and their corresponding exhaust, but the VOC species were not totally identical. Furthermore, the potential formations of ozone and secondary organic aerosols were (3.09±0.94) g·g-1 and (2.58±1.99) g·g-1, respectively, expressed by O3/VOCs and SOA/VOCs, and the benzenes and internal coating drying being the major precursors and emission node.

11.
Nat Commun ; 11(1): 2453, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415180

RESUMO

Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.

12.
Mol Nutr Food Res ; 60(10): 2161-2175, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27296520

RESUMO

SCOPE: The accumulation of misfolded α-synuclein in dopaminergic neurons is the leading cause of Parkinson's disease (PD). Resveratrol (RV), a polyphenolic compound derived from grapes and red wine, exerts a wide range of beneficial effects via activation of sirtuin 1 (SIRT1) and induction of vitagenes. Here, we assessed the role of RV in a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) induced mouse model of PD and explored its potential mechanisms. METHODS AND RESULTS: RV and EX527, a specific inhibitor of SIRT1, were administered before and after MPTP treatment. RV protected against MPTP-induced loss of dopaminergic neurons, and decreases in tyrosine hydroxylase and dopamine levels, as well as behavioral impairments. Meanwhile, RV administration activated SIRT1. Microtubule-associated protein 1 light chain 3 (LC3) was then deacetylated and redistributed from the nucleus to the cytoplasm, which provoked the autophagic degradation of α-synuclein in dopaminergic neurons. Furthermore, EX527 antagonized the neuroprotective effects of RV by reducing LC3 deacetylation and subsequent autophagic degradation of α-synuclein. CONCLUSION: We showed that RV ameliorated both motor deficits and pathological changes in MPTP-treated mice via activation of SIRT1 and subsequent LC3 deacetylation-mediated autophagic degradation of α-synuclein. Our observations suggest that RV may be a potential prophylactic and/or therapeutic agent for PD.


Assuntos
Autofagia/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Sirtuína 1/metabolismo , Estilbenos/farmacologia , alfa-Sinucleína/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Acetilação/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/tratamento farmacológico , Doença de Parkinson Secundária/metabolismo , Resveratrol
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1245-8, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30052356

RESUMO

It's one of the main goals in universe exploration to find unknown and special celestial bodies. The spectra outlier data is analyzed based on the traditional classification approaches, which is a general method of special celestial body exploration. But it's depressed that many traditional classification approaches are insensitive to the outlier data, which even influence the classification efficiencies, therefore, these methods can't accomplish the task of special celestial body exploration. In view of this, Fuzzy Large Margin and Minimum Ball Classification Model (FLM-MBC) is proposed in this paper. In FLM-MBC, part of general data and outlier data are trained to construct the minimum ball model and the fuzzy technique is introduced to reduce the noise influence to classification. Comparative experiments with C-SVM, KNN, and SVDD on the SDSS spectral datasets verify the effectiveness of the proposed FLM-MBC.

14.
Lancet Diabetes Endocrinol ; 3(4): 263-74, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25660574

RESUMO

BACKGROUND: Results of several studies have shown a possible beneficial effect of renin-angiotensin system (RAS) inhibitors on diabetic retinopathy, but the findings were contradictory. We did a systematic review and meta-analysis to assess the effect of RAS inhibitors on diabetic retinopathy. METHODS: We identified relevant publications in PubMed, Embase, Cochrane Library Central Register of Controlled Trials, and abstracts from main annual meetings. Only randomised controlled trials comparing angiotensin-converting enzyme (ACE) inhibitor or angiotensin-receptor blocker (ARB) monotherapy with other antihypertensive drugs or placebo in type 1 or type 2 diabetes were eligible for inclusion in the analysis. The primary outcomes were progression and regression of diabetic retinopathy in all patients and several subgroups. Risk ratios (RRs) with corresponding 95% CIs were pooled. We also did a network meta-analysis to assess the effect of different antihypertensive drugs on diabetic retinopathy by ranking order. This study is registered with the International Prospective Register of Systematic Reviews (PROSPERO), number CRD42013004548. FINDINGS: 21 randomised clinical trials with 13,823 participants were included in the meta-analysis. RAS inhibitors were associated with reduced risk of progression (absolute risk difference -3%, 95% CI -5 to -1; pooled RR 0.87, 95% CI 0.80-0.95; p=0.002) and increased possibility of regression of diabetic retinopathy (8%, 1-16; RR 1.39, 95% CI 1.19-1.61; p=0.00002). In normotensive patients, RAS inhibitors decreased risk of diabetic retinopathy progression (0.81, 0.69-0.94; p=0.007) and increased possibility of regression (1.43, 1.14-1.79; p=0.002). In hypertensive patients, RAS inhibitors were not associated with difference in risk of progression of diabetic retinopathy (0.93, 0.79-1.10; p=0.42) or possibility of diabetic retinopathy regression (2.21, 0.92-5.31; p=0.08). ACE inhibitors were associated with reduced risk of diabetic retinopathy progression (0.84, 0.75-0.94; p=0.002) and higher possibility of disease regression (1.50, 1.20-1.86; p=0.0003). ARBs were associated with a higher possibility of diabetic retinopathy regression (1.32, 1.07-1.61; p=0.008), but had no effect on disease progression (0.92, 0.80-1.06; p=0.25). Network meta-analysis showed the association of antihypertensive drugs with risk of diabetic retinopathy progression was lowest for ACE inhibitors, followed by ARBs, ß blockers, calcium channel blockers, and placebo in rank order. The association of antihypertensive drugs with possibility of diabetic retinopathy regression was highest for ACE inhibitors, followed by ARBs, placebo, and calcium channel blockers in rank order. INTERPRETATION: In patients with diabetes, RAS inhibitors reduce the risk of diabetic retinopathy, and increase the possibility of diabetic retinopathy regression. ACE inhibitors might be better than ARBs for treating diabetic retinopathy, and might exert the most beneficial effect on diabetic retinopathy of all widely used antihypertensive drug classes.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Antagonistas Adrenérgicos beta/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/etiologia , Progressão da Doença , Humanos , Sistema Renina-Angiotensina , Resultado do Tratamento
15.
PLoS One ; 9(5): e95485, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24830459

RESUMO

BACKGROUND: Previous studies suggested that diabetes mellitus was associated with cancer risk and prognosis, but studies investigating the relationship between diabetes mellitus and survival in patients with hepatocellular carcinoma (HCC) reported inconsistent findings. To derive a more precise estimate of the prognostic role of diabetes mellitus in HCC, we systematically reviewed published studies and carried out a meta-analysis. METHODS: Eligible articles were identified in electronic databases from their inception through September 16, 2013. To evaluate the correlation between diabetes mellitus and prognosis in HCC, the pooled hazard ratios (HR) and their 95% confidence intervals (95% CI) for poorer overall and disease-free survivals were calculated by standard meta-analysis techniques with fixed-effects or random-effects models. RESULTS: 21 studies with a total of 9,767 HCC patients stratifying overall survival and/or disease-free survival in HCC patients by diabetes mellitus status were eligible for meta-analysis. 20 studies with a total of 9,727 HCC cases investigated the overall survival, and 10 studies with a total of 2,412 HCC patients investigated the disease-free survival. The pooled HRs for overall survival and disease-free survival were 1.46 (95% CI, 1.29 to 1.66; P<0.001) and 1.57 (95% CI, 1.21 to 2.05; P = 0.001), respectively. The adjusted HRs for overall survival and disease-free survival were 1.55 (95% CI, 1.27 to 1.91; P<0.001) and 2.15 (95% CI, 1.75 to 2.63; P<0.001), respectively. In addition, for patients receiving hepatic resection, diabetes mellitus was associated with both poorer overall survival and poorer disease-free survival, and for patients receiving non-surgical treatment or patients receiving radiofrequency ablation, diabetes mellitus was associated with poorer overall survival. There was no evidence for publication bias. CONCLUSION: Diabetes mellitus is independently associated with both poorer overall survival and poorer disease-free survival in HCC patients.


Assuntos
Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/mortalidade , Complicações do Diabetes/diagnóstico , Diabetes Mellitus/diagnóstico , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/mortalidade , Complicações do Diabetes/mortalidade , Diabetes Mellitus/mortalidade , Intervalo Livre de Doença , Humanos , Fígado/patologia , Prognóstico , Fatores de Risco , Resultado do Tratamento
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(1): 263-6, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24783573

RESUMO

Although Support Vector Machine (SVM) is widely used in astronomy, it only takes the margin between classes into consideration while neglects the data distribution in each class, which seriously limits the classification efficiency. In view of this, a novel automatic classification method of star spectra data based on manifold-based discriminant analysis (MDA) and SVM is proposed in this paper. Two important concepts in MDA, manifold-based within-class scatter (MWCS) and manifold-based between-class scatter (MBCS), are introduced in the proposed method, the separating hyperplane found by which ensures MWCS is minimized and MBCS is maximized. Based on the above analysis, the corresponding optimal problem can be established, and then MDA transforms the original optimization problem to the QP dual form and we can obtain the support vectors and decision function. The classes of test samples are decided by the decision function. The advantage of the proposed method is that it not only focuses on the information between classes and distribution characteristics, but also preserves the manifold structure of each class. Experiments on SDSS star spectra datasets verify the effectiveness of the proposed method.

17.
Int J Ophthalmol ; 7(1): 71-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24634867

RESUMO

AIM: To develop an image-based objective method to precisely evaluate regional ocular bulbar injection. METHODS: Six healthy adult volunteers were photographed in four orientations (superior, inferior, nasal and temporal sides) with and without stimulating eye drops. Six line segments (covering 30°) were drawn 4mm away from the limbus on each image using ImageJ software. The graph peaks, which were derived from the areas under the line segments and corresponded to the cross-sectional grey-level of the vessels, were analyzed to obtain peak area, peak height/width (PH/PW), and peak numbers. Different-sized areas were selected to calculate the pixels based on the edge-detection algorithm. Also, conjunctival and superficial scleral vessels were analyzed separately. RESULTS: This method had a smaller coefficient of variation, especially for PH/PW, in all four orientations. Hyperaemia parameters changed the least after challenging in the superior region. Moreover, 95% of the PH/PW ratios were greater than 0.87 in conjunctival vessels and less than 1.00 in superficial scleral vessels. PH/PW significantly increased in conjunctival vessels and changed less in superficial scleral vessels. CONCLUSION: A new method of objectively assessing bulbar injection based on ocular surface images was developed. This method can be used to quantify ocular regional injection and to distinguish the superficial scleral and conjunctival vessels.

18.
Tumour Biol ; 35(3): 2009-15, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24277376

RESUMO

Polymorphisms in X-ray cross-complementing group 3 (XRCC3) are proposed to be associated with cancer susceptibility, but previous studies on the associations between XRCC3 polymorphisms and thyroid cancer are controversial. We performed a systemic review and meta-analysis to investigate the associations of XRCC3 polymorphisms with thyroid cancer risk. We used odds ratio (OR) with 95 % confidence interval (95%CI) to assess the associations. For XRCC3 C241T polymorphism, meta-analysis of total eligible studies showed that there was no association between XRCC3 C241T polymorphism and thyroid cancer risk, but subgroup analysis in Caucasians showed that there was a significant association between XRCC3 C241T polymorphism and thyroid cancer risk (T versus C: OR = 1.30, 95%CI 1.05-1.62, P = 0.01; TT versus CC: OR = 1.74, 95%CI 1.13-2.70, P = 0.01; TT versus CC/CT: OR = 1.74, 95%CI 1.16-2.60, P = 0.007). For XRCC3 A17893G polymorphism, meta-analysis of total eligible studies showed that there was an obvious association between XRCC3 A17893G polymorphism and thyroid cancer risk (GG versus AA/AG: OR = 0.57, 95%CI 0.35-0.93, P = 0.02), but subgroup analysis by ethnicity only identify the significant association in Asians. In summary, the meta-analysis suggests that there are significant associations of XRCC3 polymorphisms with thyroid cancer risk. Besides, more studies with large sample sizes are needed to further assess the associations above.


Assuntos
Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Glândula Tireoide/genética , Povo Asiático/genética , Estudos de Casos e Controles , Genótipo , Humanos , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de Risco , População Branca/genética
19.
Tumour Biol ; 35(3): 2723-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24375191

RESUMO

TP53 Arg72Pro polymorphism has been proposed to have some effects on host's susceptibility to cancer. Several studies were published to assess the association between TP53 Arg72Pro polymorphism and thyroid carcinoma, but they reported controversial results. We performed a systemic review and meta-analysis to assess the association between TP53 Arg72Pro polymorphism and thyroid carcinoma. Odds ratio (OR) with 95% confidence interval (95% CI) was used to assess the association. Fourteen individual studies with 3,483 subjects were finally included into the meta-analysis. Overall, there was an obvious association between TP53 Arg72Pro polymorphism and thyroid carcinoma under the recessive model (ProPro vs. ArgArg/ArgPro, OR = 2.02, 95% CI 1.13 to 3.62, P = 0.02). Subgroup analysis by race showed that TP53 Arg72Pro polymorphism was associated with thyroid carcinoma in Caucasians (ProPro vs. ArgArg/ArgPro, OR = 2.31, 95% CI 1.08 to 4.93, P = 0.03). Subgroup analysis by histological type showed that TP53 Arg72Pro polymorphism was not associated with a risk of different types of thyroid carcinoma. In summary, the meta-analysis suggests that TP53 Arg72Pro polymorphism is associated with thyroid carcinoma risk in Caucasians. Besides, more studies with large sample size are needed to further assess the associations above.


Assuntos
Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Glândula Tireoide/genética , Proteína Supressora de Tumor p53/genética , Estudos de Casos e Controles , Humanos , Razão de Chances , População Branca/genética
20.
Artigo em Chinês | MEDLINE | ID: mdl-23072148

RESUMO

A SYBR green real-time fluorescent quantitative PCR assay was developed for detection of Moniezia expansa mRNA with its beta-tubulin as an internal control. The results showed a good linear relationship (>0.99) between the Ct value and the concentration of positive plasmid for each gene from scolex and various proglottids. Real-time PCR showed that the expression abundance of translation elongation factor and primase was different. In conclusion, the transcription level of translation elongation factor and primase was high in both scolex and immature segment, suggesting that they may play a role in the development of scolex and immature segment.


Assuntos
Cestoides/genética , DNA Primase/genética , Fatores de Alongamento de Peptídeos/genética , Animais , RNA Mensageiro/genética
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