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1.
Front Pharmacol ; 14: 1265953, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854717

RESUMO

Anti-cancer therapy has been a significant focus of research. Developing and marketing various types and mechanisms of anti-cancer therapies benefit a variety of patients significantly. The long-term benefit to patients in evaluating the risk-benefit ratio of anti-cancer therapy has become a significant concern. This paper discusses the evaluation of long-term efficacy within the estimand framework and summarizes the various strategies for addressing potential intercurrent events. Non-proportional hazards of survival data may arise with novel anti-cancer therapies, leading to potential bias in conventional evaluation methods. This paper reviews statistical methods for addressing this issue, including novel endpoints, hypothesis testing, and efficacy estimation methods. We also discuss the influences of treatment switching. Although advanced methods have been developed to address the non-proportional hazard, they still have limitations that require continued collaborative efforts to resolve issues.

2.
Sci Total Environ ; 890: 164444, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37236482

RESUMO

The interaction of phosphate with typical soil minerals is important for understanding P cycling in natural and agricultural systems. We investigated the mechanisms of kinetics of phosphate uptake onto calcite using solid-state NMR spectroscopy. At a low phosphate concentration of 0.5 mM, the 31P single-pulse solid-state NMR peak revealed the formation of amorphous calcium phosphate (ACP) within the initial 30 min, which transformed to carbonated hydroxyapatite (CHAP) after 12 d. At a high phosphate concentration (5 mM), the results showed transformation from ACP to OCP, later to brushite, and eventually to CHAP. The formation of brushite is further supported by 31P{1H} heteronuclear correlation (HETCOR) spectra via a correlation of δP-31 = 1.7 ppm and the 1H peak at δH-1 = 6.4 ppm, which denotes the structure water of brushite. Furthermore, 13C NMR directly revealed both A-type and B-type CHAP. Generally, this work provides a detailed understanding of the aging effect on the phase transition scale of phosphate surface precipitation onto calcite in soil environments.


Assuntos
Carbonato de Cálcio , Carbonatos , Espectroscopia de Ressonância Magnética , Durapatita , Solo
3.
RSC Adv ; 12(38): 24614-24632, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36128383

RESUMO

Resistive gas sensors are considered promising candidates for gas detection, benefiting from their small size, ease of fabrication and operation convenience. The development history, performance index, device type and common host materials (metal oxide semiconductors, conductive polymers, carbon-based materials and transition metal dichalcogenides) of resistive gas sensors are firstly reviewed. This review systematically summarizes the functions, functional mechanisms, features and applications of seven kinds of guest materials (noble metals, metal heteroatoms, metal oxides, metal-organic frameworks, transition metal dichalcogenides, polymers, and multiple guest materials) used for the modification and optimization of the host materials. The introduction of guest materials enables synergistic effects and complementary advantages, introduces catalytic sites, constructs heterojunctions, promotes charge transfer, improves carrier transport, or introduces protective/sieving/enrichment layers, thereby effectively improving the sensitivity, selectivity and stability of the gas sensors. The perspectives and challenges regarding the host-guest hybrid materials-based gas sensors are also discussed.

4.
Chemosphere ; 294: 133729, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35090854

RESUMO

Fluoride pollution in groundwater is a serious problem threatening millions of people worldwide. Calcite is considered an ideal adsorbent for defluoridation owing to its widespread presence and low cost. To further enhance its performance, we synthesize a series of phosphate-modified calcites with varying phosphate concentrations. The surface modification led to the formation of a nanosized hydroxyapatite (HAP) coating on the calcite surface. With increasing concentrations of phosphate used for modification, the BET specific surface area of the adsorbents was dramatically enhanced, resulting in a great enhancement of F uptake. At low F concentrations (i.e., <1 mM), surface-modified calcite can achieve up to 25 times higher F removal efficiency than calcite. The 19F solid-state MAS NMR spectra yielded three distint peaks at δ(19F) = -86 ppm, -99 ppm, and -122 ppm, representing the formation of carbonate fluorapatite (CFA), fluorapatite (FAP), and coprecipitated F, respectively. This provides strong evidence for the contribution of newly formed HAP to F removal. In contrast, at high F concentrations (e.g., >2 mM), surface modification did not enhance F uptake by calcite. The 19F solid-state MAS NMR analysis revealed that the predominant deflurodation mechanism is the formation of CaF2 precipitates (δ(19F) = -108 ppm) for both pristine and modified calcite at high F concentrations. Under this condition, the contribution of the newly formed nanosized HAP to F uptake is insignificant. Taken together, our results demonstrated the potential of surface modification of calcite as a cost-effective technique for defluoridation for most F-rich groudwater.


Assuntos
Carbonato de Cálcio , Fluoretos , Carbonato de Cálcio/química , Durapatita/química , Fluoretos/análise , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos
5.
J Biopharm Stat ; 32(5): 705-716, 2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34958630

RESUMO

The meta-analytic approach has become the gold-standard methodology for the evaluation of surrogate endpoints and several implementations are currently available in SAS and R. The methodology is based on hierarchical models that are numerically demanding and, when the amount of data is limited, maximum likelihood algorithms may not converge or may converge to an ill-conditioned maximum such as a boundary solution. This may produce misleading conclusions and have negative implications for the evaluation of new drugs. In the present work, we explore the use of two distinct functions in R (lme and lmer) and the MIXED procedure in SAS to assess the validity of putative surrogate endpoints in the meta-analytic framework, via simulations and the analysis of a real case study. We describe some problems found with the lmer function in R that led to a poorer performance as compared with the lme function and MIXED procedure.


Assuntos
Algoritmos , Modelos Estatísticos , Biomarcadores , Humanos
6.
Acta Biochim Biophys Sin (Shanghai) ; 53(2): 201-211, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33404645

RESUMO

Osteoporosis (OP), one of the most prevalent chronic progressive bone diseases, is caused by deficiency in bone formation by osteoblasts or excessive bone resorption by osteoclasts and subsequently increases the risk of bone fractures. Emerging evidence has indicated that long noncoding RNAs (lncRNAs) play key roles in many biological processes and various disorders. However, the role and mechanism of HOX antisense intergenic RNA myeloid 1 (HOTAIRM1), a myeloid-specific lncRNA, in osteoclast differentiation, osteogenic differentiation, and OP remain unclear. In this study, we found that HOTAIRM1 was upregulated during ossification of ligamentum flavum and osteogenic differentiation, while it was downregulated in osteoclast differentiation and in the bone and serum of human and mouse with OP. Further investigation revealed that silencing Hotairm1 decreased the expression of the osteogenic markers and attenuated osteogenesis. Moreover, forced Hotairm1 expression inhibited the expressions of the osteoclastogenesis markers and alleviated receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL)-induced osteoclast differentiation. Mechanically, Hotairm1 repressed the phosphorylation of p65 and inhibitor of κBα (IκBα) and attenuated RANKL-mediated enhancement of phos-p65 and IκBα, suggesting that Hotairm1 inhibits RANKL-induced osteoclastogenesis through the NF-κB pathway. In conclusion, our data identified a crucial role of HOTAIRM1 in OP, providing a proof of this molecule as a potential diagnostic marker and a possible therapeutic target against OP.


Assuntos
Diferenciação Celular , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Osteoclastos/metabolismo , Osteogênese , Transdução de Sinais , Animais , Biomarcadores/metabolismo , Humanos , Camundongos , MicroRNAs/genética , NF-kappa B/genética , Osteoporose/genética , Osteoporose/metabolismo
7.
Nan Fang Yi Ke Da Xue Xue Bao ; 41(1): 31-38, 2021 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-33509750

RESUMO

OBJECTIVE: To investigate the regulatory role of long non-coding RNA Kcnq1ot1 in osteoclast differentiation, osteogenic differentiation and osteoporosis. METHODS: The expression of lnc-Kcnq1ot1, Bglap, Runx2, Alp, Bsp, Nfatc1, Mmp9, Ctsk and Oscar were detected by real-time quantitative PCR (qRT-PCR) in the femoral bones from mouse models of postmenopausal osteoporosis (ovariectomized mice, n=8), disuse osteoporosis (induced by tail suspension, n=14) and agerelated osteoporosis (18-month-old mice, n=8), and also in MC3T3-E1 cells during osteoblast differentiation and in murine bone marrow-derived macrophages (BMMs) and RAW264.7 cells during osteoclast differentiation. MC3T3-E1 cells with lncKcnq1ot1 knockdown by lentivirus infection were induced to differentiate into osteoblasts using osteogenic induction medium, and the expression of lnc-Kcnq1ot1, Alp and Bglap was detected with qRT-PCR and ALP activity was assessed with ALP staining. BMMs and RAW264.7 cells were transfected with siRNAs targeting lnc-Kcnq1ot1 and stimulated with RANKL and/or M-CSF, and the expression of lnc-Kcnq1ot1, Ctsk and Oscar was detected by qRT-PCR, and TRAP activity was assessed by TRAP staining. The subcellular localization of lnc-Kcnq1ot1 in MC3T3-E1 and RAW264.7 cells was determined using cell fractionation followed by qRT-PCR. RESULTS: The expression of lnc-Kcnq1ot1 was significantly upregulated during osteoblast differentiation but downregulated in the bone tissues of osteoporotic mice and during osteoclast differentiation (P < 0.05). Silencing lnc-Kcnq1ot1 obviously decreased the expression of Bglap and Alp (P < 0.05) and attenuated osteogenic medium-induced osteoblast differentiation. Knockdown of lnc-Kcnq1ot1 also promoted the expression of Ctsk and Oscar (P < 0.05) and aggravated RANKL-induced osteoclast differentiation. The results of cell fractionation and qRT-PCR demonstrated that lnc-Kcnq1ot1 was located mainly in the nuclei of MC3T3-E1 and RAW264.7 cells. CONCLUSIONS: Our data demonstrate that lnc-Kcnq1ot1 promotes osteogenic differentiation and alleviates osteoclast differentiation, suggesting the potential of lnc-Kcnq1ot1 as a therapeutic target against osteoporosis.


Assuntos
Osteoclastos , Osteogênese , Animais , Diferenciação Celular , Células Cultivadas , Camundongos , Osteoblastos
8.
Theranostics ; 9(12): 3622-3638, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281502

RESUMO

Long non-coding RNAs (lncRNAs) are involved in numerous biological functions and pathological processes. However, the clinical significance of lncRNAs and their functions in liver fibrosis remain largely unclear. Methods: The transcript of lncRNA SCARNA10 in serum and liver samples from patients with advanced hepatic fibrosis, liver tissues from two fibrosis mouse models, and cultured hepatic stellate cells (HSCs) was determined by real-time RT-PCR. The effects of lentivirus-mediated knockdown or over-expression of SCARNA10 in liver fibrosis were examined in vitro and in vivo. Moreover, the effects and mechanisms of down-regulation or over-expression of SCARNA10 on the expression of the genes involved in TGFß pathway were determined. Results: It was found lncRNA ENSMUST00000158992, named as Scarna10, was remarkably up-regulated in mouse fibrotic livers according to the microarray data. We observed that the transcript of SCARNA10 was increased in the serum and liver from patients with advanced hepatic fibrosis. Furthermore, we found that SCARNA10 promoted liver fibrosis both in vitro and in vivo through inducing hepatocytes (HCs) apoptosis and HSCs activation. Mechanistically, RNA immunoprecipitation (RIP) assays demonstrated that SCARNA10 physically associated with polycomb repressive complex 2 (PRC2). Additionally, our results demonstrated that SCARNA10 functioned as a novel positive regulator of TGFß signaling in hepatic fibrogenesis by inhibiting the binding of PRC2 to the promoters of the genes associated with ECM and TGFß pathway, thus promoting the transcription of these genes. Conclusions: Our study identified a crucial role of SCARNA10 in liver fibrosis, providing a proof of this molecule as a potential diagnostic marker and a possible therapeutic target against liver fibrosis.


Assuntos
Biomarcadores/análise , Células Estreladas do Fígado/química , Cirrose Hepática/fisiopatologia , Fígado/patologia , RNA Longo não Codificante/análise , RNA Longo não Codificante/metabolismo , Soro/química , Animais , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Humanos , Cirrose Hepática/patologia , Camundongos , Modelos Biológicos , RNA Longo não Codificante/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
FEBS Lett ; 592(24): 4051-4065, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30381822

RESUMO

Through their multiple targets, microRNAs (miRNAs) are involved in numerous physiological and pathological processes. In this study, miR-342-3p was found to be deregulated with ossification of ligament or osteoporosis. We demonstrate that silencing miR-342-3p impairs osteoblast activity and matrix mineralization, while over expression of miR-342-3p promotes osteoblast differentiation significantly. Moreover, miR-342-3p directly targets activating transcription factor 3 (ATF3), which inhibits transcription of pro-osteogenic differentiation-associated genes. In addition, there exists a higher frequency of methylation at the CpG island of the Enah/Vasp-Like (EVL) locus in undifferentiated pre-osteoblasts; however, demethylation of the EVL CpG island induces over expression of miR-342-3p during osteogenic differentiation. This study suggests that miR-342-3p may serves as a potential marker for diagnosis and treatment of ossification of ligament and osteoporosis.


Assuntos
Fator 3 Ativador da Transcrição/genética , Diferenciação Celular/genética , MicroRNAs/genética , Osteoblastos/metabolismo , Osteogênese/genética , Fator 3 Ativador da Transcrição/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Feminino , Perfilação da Expressão Gênica , Células HEK293 , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos C57BL , Ossificação do Ligamento Longitudinal Posterior/genética , Ossificação do Ligamento Longitudinal Posterior/metabolismo , Osteoblastos/citologia , Osteoporose/genética , Osteoporose/metabolismo
10.
Biochem Biophys Res Commun ; 506(3): 590-596, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30366669

RESUMO

Evidence indicates that diets enriched in Docosahexaenoic acid (DHA), a 22:6 n-3 polyunsaturated fatty acid, reduces the risk of prostate cancer, but the biochemical mechanisms are unclear. The Hippo pathway has been well established as a tumor suppressor pathway and is involved in many diverse biologic processes including cell growth, cell death, and organ size control in organisms. Here we showed that DHA induces cell growth inhibition and apoptosis of human androgen-independent prostate cancer cells dependent on the Hippo pathway. DHA inactivates YAP by promoting phosphorylation in androgen-independent prostate cancer cell lines, accompanied by increased YAP cytoplasm translocation. We also observed that DHA-induced YAP phosphorylation was reversed by both the LATS1 and MST1 siRNAs. Further experiments showed that the mechanism of DHA-induced YAP phosphorylation associated with FFAR1 and FFAR4. Down-regulation of FFAR1 and FFAR4 resulted in reduced YAP phosphorylation and reversed DHA-induced YAP phosphorylation. In addition, DHA-induced YAP phosphorylation was abolished by dominant negative Gαs and PKA inhibitor H-89. Overall, these findings define a mechanism by which FFAR1-and FFAR4-dependent activation of Hippo pathway mediates DHA-induced apoptosis of androgen-independent prostate cancer cells, thus providing a promising therapeutic target for prostate cancer.


Assuntos
Androgênios/farmacologia , Apoptose/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Via de Sinalização Hippo , Humanos , Masculino , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição , Proteínas de Sinalização YAP
11.
Mol Ther Nucleic Acids ; 12: 872-883, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30161026

RESUMO

Ossification of the ligamentum flavum (OLF) is a common spinal disorder that causes myelopathy and radiculopathy. Non-coding RNAs (ncRNAs) are involved in numerous pathological processes; however, very few ncRNAs have been identified to be correlated with OLF. Here we compared the expression of lncRNA, mRNA, circRNA, and microRNA in OLF tissues from OLF patients and healthy volunteers through mRNA, lncRNA, and circRNA microarrays and microRNA sequencing. A total of 2,054 mRNAs, 2,567 lncRNAs, 627 circRNAs, and 28 microRNAs (miRNAs) were altered during the process of OLF. qPCR confirmed the differential expression of selected mRNAs and ncRNAs. An lncRNA-mRNA co-expression network, miRNA-mRNA target prediction network, and competing endogenous RNA (ceRNA) network of circRNA-miRNA-mRNA were constructed based on a correlation analysis of the differentially expressed RNA transcripts. Subsequently, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses for the differentially expressed mRNAs and the predicted miRNAs target genes were performed. In addition, a deregulated miRNA-19b-3p-based miRNA-circRNA-lncRNA-mRNA network was confirmed, by gain-of-function and loss-of-function experiments, to function in the process of ossification. Taken together, this study provides a systematic perspective on the potential function of ncRNAs in the pathogenesis of OLF.

12.
Cancer Med ; 7(4): 1043-1055, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29533000

RESUMO

In the Asia-Pacific region, treatment options are limited for patients with relapsed/refractory chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Rituximab is widely used in this setting when purine analog-based therapies are not appropriate. We evaluated the efficacy and safety of ibrutinib compared with rituximab in a randomized, open-label phase 3 study in predominantly Asian patients with relapsed/refractory CLL/SLL. Patients (N = 160) were randomly assigned 2:1 to receive 420 mg ibrutinib (n = 106) until disease progression (PD) or unacceptable toxicity or up to six cycles of rituximab (n = 54). The primary endpoint was investigator-assessed progression-free survival (PFS); key secondary endpoints were overall response rate (ORR), overall survival (OS), and safety. Rituximab-treated patients could crossover to receive ibrutinib after confirmed PD. At data cutoff, median treatment duration was 16.4 months for ibrutinib and 4.6 months for rituximab. Ibrutinib significantly improved PFS (hazard ratio [HR] = 0.180, 95% confidence interval [CI]: 0.105-0.308). ORR was significantly higher (P < 0.0001) with ibrutinib (53.8%) than with rituximab (7.4%). At a median follow-up of 17.8 months, ibrutinib improved OS compared with rituximab (HR = 0.446; 95% CI: 0.221-0.900; P = 0.0206). Overall incidence of adverse events (AEs) was similar between treatments and was not exposure-adjusted. With ibrutinib, most common AEs were diarrhea and platelet count decreased; with rituximab, most common AEs were neutrophil count decreased and platelet count decreased. Grade ≥3 AEs were reported in 82.7% of ibrutinib-treated patients and 59.6% of rituximab-treated patients. Ibrutinib improved PFS, ORR, and OS compared with rituximab and displayed a manageable safety profile in Asian patients with relapsed/refractory CLL/SLL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Adenina/análogos & derivados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Piperidinas , Modelos de Riscos Proporcionais , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem , Recidiva , Retratamento , Rituximab/administração & dosagem , Resultado do Tratamento
13.
Biochim Biophys Acta Mol Basis Dis ; 1863(9): 2398-2407, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28502705

RESUMO

Accumulation of amyloid ß protein (Aß)-containing neuritic plaques in the brain is a neuropathological feature of Alzheimer's disease (AD). The ß-site APP-cleaving enzyme 1 (BACE1) is essential for Aß generation and dysregulation of BACE1 expression may lead to AD pathogenesis. Bcl-2-associated athanogen 1M (BAG-1M), initially identified as an anti-apoptotic protein, has also been found to be highly expressed in the same neurons that contain intracellular amyloid in the hippocampus of AD patient. In this report, we found that over-expression of BAG-1M enhances BACE1-mediated cleavage of amyloid precursor protein (APP) and Aß production by up-regulating BACE1 gene transcription. The regulation of BACE1 transcription by BAG-1M was dependent on NF-κB, as BAG-1M complexes NF-κB at the promoter of BACE1 gene and co-activates NF-κB-facilitated BACE1 transcription. Moreover, expression of BAG-1M by lentiviral vector in the hippocampus of AD transgenic model mice promotes Aß generation and formation of neuritic plaque, and subsequently accelerates memory deficits of the mice. These results provide evidence for an emerging role of BAG-1M in the regulation of BACE1 expression and AD pathogenesis and that targeting the BAG-1M-NF-κB complex may provide a mechanism for inhibiting Aß production and plaque formation.


Assuntos
Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/biossíntese , Precursor de Proteína beta-Amiloide/biossíntese , Ácido Aspártico Endopeptidases/biossíntese , Proteínas de Ligação a DNA/metabolismo , Transtornos da Memória/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/genética , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Humanos , Transtornos da Memória/genética , Transtornos da Memória/patologia , Camundongos , Camundongos Transgênicos , Fatores de Transcrição/genética
14.
FEBS J ; 284(7): 1096-1109, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28296235

RESUMO

The aberrant accumulation of ß-amyloid peptide (Aß) in the brain is a key feature of Alzheimer's disease (AD), and enhanced cleavage of ß-amyloid precursor protein (APP) by ß-site APP-cleaving enzyme 1 (BACE1) has a major causative role in AD. Despite their prominence in AD pathogenesis, the regulation of BACE1 and APP is incompletely understood. In this study, we report that the circular RNA circular RNA sponge for miR-7 (ciRS-7) has an important role in regulating BACE1 and APP protein levels. Previous studies have shown that ciRS-7, which is highly expressed in the human brain, is down-regulated in the brain of people with AD but the relevance of this finding was not clear. We have found that ciRS-7 is not involved in the regulation of APP and BACE1 gene expression, but instead reduces the protein levels of APP and BACE1 by promoting their degradation via the proteasome and lysosome. Consequently, overexpression of ciRS-7 reduces the generation of Aß, indicating a potential neuroprotective role of ciRS-7. Our data also suggest that ciRS-7 modulates APP and BACE1 levels in a nuclear factor-κB (NF-κB)-dependent manner: ciRS-7 expression inhibits translation of NF-κB and induces its cytoplasmic localization, thus derepressing expression of UCHL1, which promotes APP and BACE1 degradation. Additionally, we demonstrated that APP reduces the level of ciRS-7, revealing a mutual regulation of ciRS-7 and APP. Taken together, our data provide a molecular mechanism implicating reduced ciRS-7 expression in AD, suggesting that ciRS-7 may represent a useful target in the development of therapeutic strategies for AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Neurônios/metabolismo , RNA/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Precursor de Proteína beta-Amiloide/genética , Ácido Aspártico Endopeptidases/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Genes Reporter , Células HEK293 , Humanos , Luciferases/genética , Luciferases/metabolismo , Lisossomos/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , NF-kappa B/genética , Neurônios/citologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Biossíntese de Proteínas , Proteólise , RNA/genética , RNA Circular , Transdução de Sinais , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
15.
J Ophthalmol ; 2015: 737198, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26697212

RESUMO

Purpose. To evaluate the effectiveness and safety of three biodegradable terpolymers prepared from L-lactide, trimethylene carbonate, and glycolide (PTLGA) as an aid for trabeculectomy compared with the Ologen (OLO). Methods. Trabeculectomy was carried out on rabbits with implantation made from OLO or three PTLGA terpolymers. Intraocular pressure (IOP) was recorded 1, 2, 3, and 6 months postoperatively and bleb evaluations were performed using ultrasound biomicroscopy (UBM) 3 months after surgery, optical coherence tomography (OCT) every month, and transmission electron microscopy (TEM) six months after surgery followed by histological examination 1, 2, 3, and 6 months postoperatively. Result. IOP was significantly reduced in all groups after surgery. There were no significant differences in the IOL between groups at any time after implantation. There was no significant difference between the groups examined by OCT, UBM, and TEM. Exposure of the implant was observed in one eye from the OLO group and one eye in the P1. Subconjunctiva hyperblastosis was observed in one eye from group P3 and two eyes from the OLO group. Conclusions. Subconjunctival implantation of filtering devices made from PTLGA may present a safe and effective additional surgical tool for the treatment of filtering surgery. Fewer complications were observed in the group with P2 implants compared to other groups.

16.
Mol Vis ; 14: 2067-75, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19023448

RESUMO

PURPOSE: Usher syndrome type II (USH2) is the most common form of Usher syndrome, an autosomal recessive disorder characterized by moderate to severe hearing loss, postpuberal onset of retinitis pigmentosa (RP), and normal vestibular function. Mutations in the USH2A gene have been shown to be responsible for most cases of USH2. To further elucidate the role of USH2A in USH2, mutation screening was undertaken in three Chinese families with USH2. METHODS: Three unrelated Chinese families, consisting of six patients and 10 unaffected relatives, were examined clinically, and 100 normal Chinese individuals served as controls. Genomic DNA was extracted from the venous blood of all participants. The coding region (exons 2-72), including the intron-exon boundary of USH2A, was amplified by polymerase chain reaction (PCR). The PCR products amplified from the three probands were analyzed using direct sequencing to screen sequence variants. Whenever substitutions were identified in a patient, restriction fragment length polymorphism analysis, or single strand conformation polymorphism analysis was performed on all available family members and the control group. RESULTS: Fundus examination revealed typical fundus features of RP, including narrowing of the vessels, bone-speckle pigmentation, and waxy optic discs. The ERG wave amplitudes of three probands were undetectable. Audiometric tests indicated moderate to severe sensorineural hearing impairment. Vestibular function was normal. Five novel mutations (one small insertion, one small deletion, one nonsense, one missense, and one splice site) were detected in three families after sequence analysis of USH2A. Of the five mutations, four were located in exons 22-72, specific to the long isoform of USH2A. CONCLUSIONS: The mutations found in our study broaden the spectrum of USH2A mutations. Our results further indicate that the long isoform of USH2A may harbor even more mutations of the USH2A gene.


Assuntos
Povo Asiático/genética , Proteínas da Matriz Extracelular/genética , Mutação/genética , Síndromes de Usher/genética , Adolescente , Sequência de Aminoácidos , Sequência de Bases , Criança , China , Análise Mutacional de DNA , Proteínas da Matriz Extracelular/química , Família , Feminino , Fundo de Olho , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Polimorfismo de Fragmento de Restrição , Polimorfismo Conformacional de Fita Simples , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Alinhamento de Sequência
17.
Retina ; 28(3): 504-10, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18327146

RESUMO

PURPOSE: To evaluate the toxic effects of two triamcinolone acetonide (TA) vehicles on rabbit retina at different volumes. METHODS: Vehicle A and B were prepared from two TA injections by centrifugation. Thirty-six New Zealand white rabbits were intravitreally injected with vehicle A, B, or balanced saline solution at 0.1 mL or 0.2 mL respectively. The eyes were examined by indirect ophthalmoscope, light microscope, and transmission electron microscope up to week 8 postinjection. RESULTS: Eyes with vehicle A appeared normal under the ophthalmoscope, but showed disorganization in retinal inner nuclear layer and photoreceptor layer in pathologic analyses. Eyes with vehicle B displayed more significant retinal changes including retinal hemorrhage, vascular narrowing, myelinated fiber edema, retinal necrosis and atrophy, and photoreceptor apoptosis. There was an increase in degree of the above damages as the volume of either vehicle increased. CONCLUSION: Both vehicle A and B caused volume-related toxicity in rabbit retina. The intensity of the toxic effects of different vehicles may differ. Reducing or decanting the vehicles should be considered before intravitreal use of TA injections.


Assuntos
Veículos Farmacêuticos/toxicidade , Retina/efeitos dos fármacos , Doenças Retinianas/induzido quimicamente , Triancinolona Acetonida/química , Acetatos/toxicidade , Animais , Álcool Benzílico/toxicidade , Carboximetilcelulose Sódica/toxicidade , Combinação de Medicamentos , Injeções , Minerais/toxicidade , Polissorbatos/toxicidade , Coelhos , Retina/ultraestrutura , Doenças Retinianas/diagnóstico , Cloreto de Sódio/toxicidade , Corpo Vítreo
18.
Zhonghua Yan Ke Za Zhi ; 42(6): 492-5, 2006 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-16857126

RESUMO

OBJECTIVE: To investigate the clinical features of central retinal vein occlusion (CRVO) complicating exudative retinal detachment (ERD). METHODS: General health, vision, intraocular pressure, appearance of the fundus and fundus fluorescein angiography (FFA) and the results of ultrasound examination in cases with CRVO complicating ERD were analyzed. RESULTS: Eight patients were male and 7 patients were female. Age of those patients ranged from 18 to 42 years, averaged 25 years. Five cases combined with neovascular glaucoma. Initial vision ranged from 0.05 to light perception. There were notably edema and hemorrhage in the macular region. Extensive exudative appeared at the edge of edema and detachment region. The extent of retinal detachment was 2/12 - 5/12 quadrant at sitting position. No collateral vessels were found on the optic disk. FFA showed extensive blockage by the hemorrhages or capillary nonperfusion. CONCLUSIONS: ERD is a rare and severe complication of CRVO, which usually develops in young patients and combines with neovascular glaucoma. The appearance in fundus and FFA shows a characteristic features.


Assuntos
Descolamento Retiniano/diagnóstico , Oclusão da Veia Retiniana/diagnóstico , Adolescente , Adulto , Feminino , Angiofluoresceinografia , Fundo de Olho , Glaucoma Neovascular/diagnóstico , Glaucoma Neovascular/etiologia , Humanos , Pressão Intraocular , Masculino , Descolamento Retiniano/etiologia , Oclusão da Veia Retiniana/complicações , Estudos Retrospectivos , Acuidade Visual
19.
Mol Vis ; 11: 738-43, 2005 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-16179904

RESUMO

PURPOSE: Bietti crystalline corneoretinal dystrophy (BCD) is an autosomal recessive disorder of retinal degeneration characterized by small glittering crystals in the corneal limbus, posterior pole of the eye, and circulating lymphocytes. Recently mutations in a new gene CYP4V2, encoding a protein belonging to a novel member of the cytochrome P450 family, have been identified as the cause of BCD. To further characterize the role of CYP4V2 in BCD, mutation screening has been undertaken in a cohort of affected patients with BCD from China. METHODS: Eight unrelated families, including 14 patients and 18 unaffected relatives, and 10 sporadic patients were examined clinically. Fifty normal Chinese individuals served as control subjects. Genomic DNA was extracted from venous blood of all participants. The coding region (including the intron-exon boundary) of CYP4V2 was amplified by polymerase chain reaction (PCR). The PCR products were analyzed using direct sequencing and single strand conformation polymorphism (SSCP). RESULTS: Fundus examination revealed clinical features of BCD with many small, yellowish-sparkling crystals at the posterior pole of the fundus. Sequencing of CYP4V2 identified nine (5 missense, 1 nonsense, 2 deletion, and 1 point A-->G transversion in the splice acceptor site) mutations in 8 families and 9 independent patients. Five of these mutations are novel. CONCLUSIONS: Our finding expands the spectrum of CYP4V2 mutations causing BCD, and further confirms the role of CYP4V2 in the pathogenesis of BCD.


Assuntos
Distrofias Hereditárias da Córnea/genética , Sistema Enzimático do Citocromo P-450/genética , Mutação , Degeneração Retiniana/genética , Família 4 do Citocromo P450 , Análise Mutacional de DNA , Feminino , Genes Recessivos , Humanos , Masculino , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA
20.
Zhonghua Yan Ke Za Zhi ; 41(7): 606-9, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16080894

RESUMO

OBJECTIVE: To evaluate the efficiency and safety of intravitreal injection of triamcinolone acetonide for treatment of retinal detachment with choroidal detachment. METHODS: 13 the patients (13 eyes) of retinal detachment with choroidal detachment were chosen and triamcinolone acetonide 0.1 ml (4 mg) were administrated via intravitreal injection through pars plana. The therapeutic effects on uveitis and choroidal detachment was analyzed. The retinal reattachment surgery was performed five to ten days after the injection. RESULTS: all 13 patients receiving triamcinolone acetonide demonstrated alleviated uveitis to some degree. The rate of retinal holes detection increased from 2/13 pre-injection to 7/13 post-operation. Choroidal detachment disappeared in most of cases within 10 days triamcinolone acetonide injection. Five eyes underwent scleral buckling, 6 eyes underwent with vitrectomy, and 2 patients abandoned surgery. The average follow up after surgery was 4 and half months. All eyes received with triamcinolone acetonide injection and surgery had retinal reattached successfully and no side effects were detected. CONCLUSIONS: Intravitreal injection of triamcinolone acetonide was an effective and safe method to treat choroidal detachment and alleviate uveitis. The injection simplified surgery procedure and improve the success rate of retinal detachment.


Assuntos
Doenças da Coroide/tratamento farmacológico , Descolamento Retiniano/tratamento farmacológico , Triancinolona Acetonida/uso terapêutico , Corpo Vítreo/efeitos dos fármacos , Adulto , Idoso , Doenças da Coroide/cirurgia , Terapia Combinada , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Descolamento Retiniano/cirurgia , Resultado do Tratamento , Triancinolona Acetonida/administração & dosagem
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