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1.
Sensors (Basel) ; 23(19)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37837160

RESUMO

Characterizing motor subtypes of Parkinson's disease (PD) is an important aspect of clinical care that is useful for prognosis and medical management. Although all PD cases involve the loss of dopaminergic neurons in the brain, individual cases may present with different combinations of motor signs, which may indicate differences in underlying pathology and potential response to treatment. However, the conventional method for distinguishing PD motor subtypes involves resource-intensive physical examination by a movement disorders specialist. Moreover, the standardized rating scales for PD rely on subjective observation, which requires specialized training and unavoidable inter-rater variability. In this work, we propose a system that uses machine learning models to automatically and objectively identify some PD motor subtypes, specifically Tremor-Dominant (TD) and Postural Instability and Gait Difficulty (PIGD), from 3D kinematic data recorded during walking tasks for patients with PD (MDS-UPDRS-III Score, 34.7 ± 10.5, average disease duration 7.5 ± 4.5 years). This study demonstrates a machine learning model utilizing kinematic data that identifies PD motor subtypes with a 79.6% F1 score (N = 55 patients with parkinsonism). This significantly outperformed a comparison model using classification based on gait features (19.8% F1 score). Variants of our model trained to individual patients achieved a 95.4% F1 score. This analysis revealed that both temporal, spectral, and statistical features from lower body movements are helpful in distinguishing motor subtypes. Automatically assessing PD motor subtypes simply from walking may reduce the time and resources required from specialists, thereby improving patient care for PD treatments. Furthermore, this system can provide objective assessments to track the changes in PD motor subtypes over time to implement and modify appropriate treatment plans for individual patients as needed.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Humanos , Doença de Parkinson/patologia , Tremor/diagnóstico , Fenômenos Biomecânicos , Marcha , Encéfalo/patologia , Transtornos Neurológicos da Marcha/diagnóstico , Equilíbrio Postural/fisiologia
2.
Zhonghua Gan Zang Bing Za Zhi ; 30(9): 1012-1016, 2022 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-36299200

RESUMO

Globally, metabolic-asssociated fatty liver disease has become a significant health burden due to its complex pathogenesis, and there are no specific and effective therapeutic drugs to date. The onset and progression of metabolic-asssociated fatty liver disease is closely associated with improper dietary habits. The cornerstone to treat metabolic-asssociated fatty liver disease is weight loss through a well-balanced diet. This article summarizes and discusses the research progress at home and abroad in relationship to metabolic-asssociated fatty liver disease and dietary patterns such as the Mediterranean diet, the DASH diet, an energy-restricted balanced diet, a low fat diet, a low carbohydrate diet, a western diet, an animal food diet, a traditional diet, and others. In addition, it categorizes the effects of various dietary patterns on the prevention, treatment, or induction of several issues that need further metabolic-asssociated fatty liver disease research for subsequent reference.


Assuntos
Dieta Mediterrânea , Hepatopatia Gordurosa não Alcoólica , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Dieta com Restrição de Gorduras , Redução de Peso , Fígado
3.
Zhonghua Yi Xue Za Zhi ; 100(48): 3863-3869, 2020 Dec 29.
Artigo em Chinês | MEDLINE | ID: mdl-33371632

RESUMO

Objective: To investigate the role and regulation mechanism of X box binding protein 1 (XBP1) for hypoxia/reoxygenation(H/R) injury in mouse renal tubular epithelial cells (TCMK-1) through thioredoxin interacting protein (TXNIP)-nucleotide-binding domain (NOD)-like receptor protein (TXNIP-NLRP3) signaling pathway. Methods: The cells were divided into 4 groups: si-NC group transfected with negative control siRNA (si-NC), si-XBP1 group transfected with siRNA targeting XBP1 (si-XBP1), si-NC+H/R group transfected with si-NC and exposed to H/R, and si-XBP1+H/R group transfected with si-XBP1 and exposed to H/R. The Annexin Ⅴ/PI double-staining method was used to detect cell apoptosis; The mitochondrial membrane potential (MMP) was determined by using JC-1 dye; The mitochondrial reactive oxygen species (mROS) was assessed by using MitoSOX™ dye. The interference efficiency of XBP1 was tested by Western blotting and quantitative real-time polymerase chain reaction. The expression levels of TXNIP, NLRP3 and IL-1ß protein were detected by Western blotting. The colocalization of mitochondria and TXNIP was detected by double-labeling immunofluorescent staining. The intergroup difference was compared by using an independent samples t-test. Results: Compared with the si-NC group, more mROS, apoptosis and lower MMP were observed in si-NC+H/R group. Compared with the si-NC+H/R group, less apoptosis (12.08±0.51 vs 19.01±1.80, P<0.05), mROS (34.63±0.64 vs 48.17±1.84, P<0.01) and higher MMP (1.03±0.11 vs 0.45±0.08, P<0.05) were observed in si-XBP1+H/R group. Down-regulation of XBP1U (protein: 1.31±0.18 vs 0.23±0.02, P<0.01; mRNA: 1.12±0.07 vs 0.38±0.01, P<0.001) and XBP1S (protein: 1.13±0.17 vs 0.28±0.07, P<0.01; mRNA: 8.39±0.63 vs 2.45±0.22, P<0.001) inhibited expression of TXNIP (0.15±0.02 vs 0.04±0.01, P<0.01), NLRP3 (1.13±0.12 vs 0.51±0.12, P<0.05) and IL-1ß (1.02±0.04 vs 0.19±0.06, P<0.001) during H/R. Meanwhile, TXNIP exhibited significantly much less colocalization with mitochondria in the si-XBP1+H/R group. Conclusion: Supression of XBP1 expression can effectively alleviate H/R-induced TCMK-1 cells injury, whose mechanism may be inhibition of TXNIP-induced NLRP3 inflammasome activation.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Proteínas de Transporte , Células Epiteliais/metabolismo , Hipóxia , Inflamassomos/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Tiorredoxinas/metabolismo , Proteína 1 de Ligação a X-Box/genética
4.
J Mech Behav Biomed Mater ; 108: 103815, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32469722

RESUMO

The implant surface and tissue experience strain when micro-motion occurs at the bone-implant interface under physiological loading. Moreover, strain is also introduced on the surface during mechanical processing of biomedical devices. Both these situations can induce phase transformation depending on the degree of stability of the microstructural constituents. In this regard, we elucidate here the interplay between mechanically-induced phase transformation (strain-induced martensite) in austenitic stainless steel on osteoblast functions. Strain-induced martensite significantly impacted cellular functions, notably, cell attachment, cell-surface interactions, proliferation, and synthesis of prominent proteins (fibronectin, actin, and vinculin). Strain-induced martensite favorably modulated cellular activity and contributed to small differences in hydrophilicity in relation to the non-strained austenitic stainless steel surface. The study provides a pathway for tuning biological functionality via microstructural control facilitated by mechanical strain.


Assuntos
Próteses e Implantes , Aço Inoxidável , Comunicação Celular
5.
J Mech Behav Biomed Mater ; 101: 103433, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539734

RESUMO

Conventional coarse-grained (CG) biomedical austenitic stainless steel with grain size in the micrometer range was subjected to a novel phase reversion concept involving severe cold deformation, followed by annealing, when the cold deformed martensite reverts to austenite with grain size in the nanometer/ultrafine (NG/UFG) regime (~200-400 nm). The mechanical behavior of CG and NG/UFG steels was studied via load-controlled and displacement-controlled experiments using a nanoindentation technique with the aim to simulate micromotion. The plastic zone associated with the indentation-induced deformed region was characterized by post-mortem electron microscopy of the deformed region to elucidate the deformation mechanism. Nanoscale twinning was the deformation mechanism in steel with grain size in the NG/UFG regime, and contributed to the ductility of high strength steel. In contrast, strain-induced martensite contributed to the ductility of low strength CG steel with micrometer grain size. Interestingly, besides the differences in the mechanical behavior, the biological functions of the two steels were remarkably different. Higher cell attachment, proliferation and higher expression level of prominent proteins, fibronection, actin and vinculin were favored by a surface with grain size in the nanometer regime and was in striking contrast with the surface with micrometer grain size. This behavior is attributed to the differences in the fraction of grain boundaries that are high energy two-dimensional defects. The study advances our understanding of the mechanical behavior of biomaterials and their cellular functions.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ligas Dentárias/química , Fenômenos Mecânicos , Nanoestruturas/química , Aço Inoxidável/química , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos
7.
Nat Commun ; 9(1): 2102, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844421

RESUMO

Dense crossbar arrays of non-volatile memory (NVM) can potentially enable massively parallel and highly energy-efficient neuromorphic computing systems. The key requirements for the NVM elements are continuous (analog-like) conductance tuning capability and switching symmetry with acceptable noise levels. However, most NVM devices show non-linear and asymmetric switching behaviors. Such non-linear behaviors render separation of signal and noise extremely difficult with conventional characterization techniques. In this study, we establish a practical methodology based on Gaussian process regression to address this issue. The methodology is agnostic to switching mechanisms and applicable to various NVM devices. We show tradeoff between switching symmetry and signal-to-noise ratio for HfO2-based resistive random access memory. Then, we characterize 1000 phase-change memory devices based on Ge2Sb2Te5 and separate total variability into device-to-device variability and inherent randomness from individual devices. These results highlight the usefulness of our methodology to realize ideal NVM devices for neuromorphic computing.

8.
Genet Mol Res ; 14(4): 12377-85, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26505387

RESUMO

We determined whether salubrinal can protect cardio-myocytes from doxorubicin-induced apoptosis and explored the related mechanisms to provide experimental evidence for exploring novel drug candidates to decrease cardiac toxicity. Neonatal rat cardiomyocytes were isolated, cultured in vitro, and pretreated with salubrinal (10, 20, or 40 µM) to observe their response to doxorubicin-induced cell apoptosis. Lactate dehydrogenase assay, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling staining, and flow cytometry were used to assess the extent of cardiomyocyte apoptosis. Fluorescent probes conjugated with 2',7'-dichlorofluorescein diacetate and a chemiluminescence assay were used to detect the pro-duction of reactive oxygen species. Western blotting was employed to quantify expression levels of cleaved caspase-3, cytosolic cytochrome c, and B-cell lymphoma-extra large (Bcl-xL). The mechanisms of salubrinal-related functions were also explored. Salubrinal effectively inhibited doxorubicin-induced reactive oxygen species production and nicotinamide adenine dinucleotide phosphate oxidase activation, decreased the levels of cleaved caspase-3 and cytosol cytochrome c, and increased Bcl-xL expression, thereby protecting cardiomyocytes from doxorubicin-induced apoptosis. Furthermore, salubrinal was found to protect cardiomyocytes by decreasing the dephosphorylation of eukaryotic translation initiation factor 2α (eIF2α). Salubrinal can protect cardiomyocytes from doxorubicin-induced apoptosis through its effects on eIF2α. It possibly ameliorates cardiac toxicity and can be used in clinical practice.


Assuntos
Cinamatos/farmacologia , Doxorrubicina/farmacologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Tioureia/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Ratos , Ratos Sprague-Dawley , Tioureia/farmacologia
9.
Eur J Pain ; 19(5): 639-48, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25158907

RESUMO

BACKGROUND: Overexpression of the voltage-gated calcium channel (VGCC) alpha-2-delta1 subunit protein (Cav α2 δ1 ) has been shown to cause pain states. However, whether VGCC are involved in pain states driven by abnormal Cav α2 δ1 expression is not known. METHODS: Intrathecal injection of N-, P/Q- and L-type VGCC blockers were tested in two models: a transgenic neuronal Cav α2 δ1 overexpression (TG) model with behavioural hypersensitivity and a spinal nerve ligation (SNL) model with Cav α2 δ1 overexpression in sensory pathways and neuropathy pain states. RESULTS: The nociceptive response to mechanical stimuli was significantly attenuated in both models with ω-conotoxin GVIA (an N-type VGCC blocker) and nifedipine (an L-type VGCC blocker), in which ω-conotoxin GVIA appeared more potent than nifedipine. Treatments with ω-agatoxin IVA (P-VGCC blocker), but not ω-conotoxin MVIIC (Q-VGCC blocker) had similar potency in the TG model as the N-type VGCC blocker, while both ω-agatoxin IVA and ω-conotoxin MVIIC had minimal effects in the SNL model compared with controls. CONCLUSION: These findings suggest that, at the spinal level, N- and L-type VGCC are likely involved in behavioural hypersensitivity states driven by Cav α2 δ1 overexpression. Q-type VGCC has minimal effects in both models. The anti-nociceptive effects of P-type VGCC blocker in the Cav α2 δ1 TG mice, but minimally at the SNL model with presynaptic Cav α2 δ1 up-regulation, suggest that its potential action site(s) is at the post-synaptic and/or supraspinal level. These findings support that N-, L- and P/Q-type VGCC have differential contributions to behavioural hypersensitivity modulated by Cav α2 δ1 dysregulation at the spinal cord level.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Nociceptividade/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Canais de Cálcio/genética , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo N/efeitos dos fármacos , Vias Eferentes/metabolismo , Hiperalgesia/psicologia , Injeções Espinhais , Ligadura , Masculino , Camundongos , Neuralgia/patologia , Neuralgia/fisiopatologia , Nifedipino/farmacologia , Medição da Dor/efeitos dos fármacos , Nervos Espinhais/lesões , ômega-Conotoxina GVIA/farmacologia
10.
J Fish Biol ; 85(4): 1279-96, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25159100

RESUMO

Specific growth hormone (GH)-binding protein (Ghbp) was purified from Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss plasma with immunoprecipitation and characterized in cross-linking studies using autoradiography and western blots. The size of the Ghbp was estimated to be c. 53 kDa. A radioimmunoassay was established to measure Ghbp in salmonids, using antibodies specific against the extracellular segment of the S. salar growth hormone receptor 1 (grh1; GenBank AY462105). Plasma Ghbp levels were measured in S. salar smolts in fresh water and after transfer to seawater (SW; experiments 1 and 2), and in post-smolts kept at different salinities (0, 12, 22 and 34) for 3 months (experiment 3). A transient increase in plasma Ghbp, which lasted for 1 month or less, was noted in smolts after transfer to SW. Concomitantly, plasma GH and gill Na(+) -K(+) -ATPase activity increased during smoltification (in experiment 2). No difference in plasma Ghbp was evident between post-smolts kept at different salinities, although the fish kept at salinity 34 had higher plasma GH than the group kept at salinity 22 and higher hepatic ghr1 expression than post-smolts kept at salinity 12. This suggests that plasma Ghbp regulation may respond to salinity changes in the short term. The lack of correlation between Ghbp, plasma GH and hepatic ghr1 expression in the long-term post-smolt experiment indicates that Ghbp levels may be regulated independently of other components of the endocrine GH system in salmonids.


Assuntos
Proteínas de Transporte/sangue , Salmo salar/sangue , Aclimatação/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/sangue , Brânquias/enzimologia , Dados de Sequência Molecular , Radioimunoensaio , Proteínas Recombinantes/sangue , Água do Mar , ATPase Trocadora de Sódio-Potássio/metabolismo
11.
Transplant Proc ; 45(2): 639-42, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23498803

RESUMO

UNLABELLED: The aim of this study was to explore underlying mechanisms of transplant arteriosclerosis (TA) based on intimal thickening that involve activation of vascular smooth muscle cells (VSMCs) and angiogenesis. We also examined the effects of adenovirus-mediated anti-sense extracellular signal-regulated kinase 2 (ERK2) (Adanti-ERK2) gene therapy on TA. METHODS: We employed a rat aorta transplantation model (Brown-Norway → Lewis). The animals were divided into: (1) an isograft group (n = 6), (2) an empty control group (n = 6), (3) the Ad-LacZ group (n = 6), and (4) the adanti-ERK2 group (n = 6). At 60 days after transplantation, we documented the ratio of intima/(intima + media) the isografts pathologically. Staining for α-actin and platelet-derived growth factor (PDGF)-BB was performed to analyze the migration and secretion of VSMCs. We evaluated angiogenesis and COX-2 staining. RESULT: Isografts showed normal histology; allografts from the empty control group and the Ad-LacZ group displayed typical TA lesions, while the pathology was significantly improved among the adanti-ERK2 group. The ratios of intima/(intima + media) were 7.6 ± 2.1%, 81.4% ± 6.7%, 85.9% ± 9.4%, and 15.9% ± 4.1% among the isograft group, the empty control, the Ad-LacZ, and the adanti-ERK2 groups respectively. The α-actin+ cells in the intima per field (×400) were 2.1 ± 1.1, 71.3 ± 9.2, 76.4 ± 11.3, and 34.8 ± 5.3, PDGF-BB+ cells, 0.9 ± 0.5, 28.4 ± 3.4, 29.1 ± 3.2, and 8.6 ± 1.7; COX-2+ cells in new capillaries were none, 36.3 ± 8.3, 40.9 ± 9.2, and 10.4 ± 3.9 respectively (P < .05). CONCLUSION: Intimal thickening a key feature of TA, involves activation of VSMC (proliferation, migration and secretion), and the accompanying angiogenesis. Adanti-ERK2 gene therapy modulates the mechanisms, protecting allografts against TA.


Assuntos
Adenoviridae/genética , Aorta Abdominal/transplante , Arteriosclerose/prevenção & controle , DNA Antissenso/metabolismo , Terapia Genética/métodos , Vetores Genéticos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/transplante , Neovascularização Patológica , Transdução Genética , Animais , Aorta Abdominal/enzimologia , Aorta Abdominal/patologia , Arteriosclerose/enzimologia , Arteriosclerose/genética , Arteriosclerose/patologia , Becaplermina , Movimento Celular , Proliferação de Células , Ciclo-Oxigenase 2/metabolismo , DNA Antissenso/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/patologia , Miócitos de Músculo Liso/transplante , Neointima , Proteínas Proto-Oncogênicas c-sis/metabolismo , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew
12.
Transplant Proc ; 45(2): 677-83, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23267786

RESUMO

BACKGROUND: Infection with some types of parasites can significantly prolong allograft survival in mice. It is unknown whether the soluble tachyzoite antigen (STAg) from Toxoplasma gondii has the same effect and by what mechanism it acts. METHODS: A mouse model of cardiac and skin allograft transplantation was established between BALB/c (H-2(d)) and C57BL/6(H-2(b)) mice. T gondii STAg was prepared, and 5 µg was administered subcutaneously to recipient mice 4 days before transplantation. The graft status was checked daily, and histologic and immunohistochemical assays were used to evaluate rejection. The serum cytokine levels from the recipient mice were analyzed by Luminex. RESULT: The administration of 5 µg STAg 4 days before transplantation significantly prolonged the survival time of the heart and skin allografts to 85.17 ± 14.06 and 24.17 ± 2.32 days, respectively. Immunohistochemical staining showed that the CD4(+) and CD8(+) T lymphocytes were markedly reduced in the allografts at day 7 posttransplantation. Notably, interleukin (IL)-12, IL-2, and IL-17 levels were significantly reduced in the serum of mice treated with STAg compared with untreated mice 7 days after transplantation. In contrast, the levels of the antiinflammatory cytokine IL-10 were elevated. CONCLUSION: A single administration of STAg before transplantation can significantly prolong the allograft survival time, which is accompanied by impaired lymphocyte infiltration and a reduced Th1 response.


Assuntos
Antígenos de Protozoários/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Transplante de Coração/imunologia , Transplante de Pele/imunologia , Toxoplasma/imunologia , Animais , Antígenos de Protozoários/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Transplante de Coração/efeitos adversos , Imuno-Histoquímica , Injeções Subcutâneas , Interleucinas/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Transplante de Pele/efeitos adversos , Fatores de Tempo
13.
Oral Dis ; 19(6): 611-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23231387

RESUMO

BACKGROUND: MicroRNAs play important roles in carcinogenesis. A preliminary screening study suggested that down-regulation of miR-370 occurs in oral squamous cell carcinoma (OSCC) tissue. Insulin receptor substratre-1 (IRS-1) is the substrate of insulin-like growth factor receptor (IGFR), which modulates AKT/mTOR activation in malignancies. The relationship between miR-370 and IRS-1, and their functional roles in OSCC pathogenesis are unclear. MATERIALS AND METHODS: Primary OSCC specimens were examined for miR-370 expression. Exogenous expression of miR-370 was established using both stable subclones and transient expression, and these were used to gain insights into miR-370's functions in OSCC cells. Knockdown of miR-370 and IRS-1 was also carried out in OSCC cells using a small interference oligonucleotide approach. RESULTS: Squamous cell carcinoma tissues with perineural invasion had lowered miR-370 expression compared with contrasting OSCC. OSCC cells also exhibited lower miR-370 expression than normal oral keratinocytes, and this can be reversed by treatment with 5-aza-2'-deoxycytidine. Exogenous miR-370 expression decreases the migration and anchorage-independent growth of OSCC cells, which implies a suppressor role for miR-370. The enhancement of anchorage-independent growth of OSCC cells through miR-370 inhibiting can be reduced by knockdown of IRS-1 expression. CONCLUSION: This study concludes that miR-370 is able to target IRS-1 for oral tumorigenesis.


Assuntos
Carcinoma de Células Escamosas/patologia , Proteínas Substratos do Receptor de Insulina/fisiologia , MicroRNAs/fisiologia , Neoplasias Bucais/patologia , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Carcinogênese/patologia , Adesão Celular/genética , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular/genética , Células Cultivadas , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Queratinócitos/efeitos dos fármacos , Queratinócitos/patologia , MicroRNAs/análise , MicroRNAs/genética , Invasividade Neoplásica , Estadiamento de Neoplasias , Proteína Oncogênica v-akt/fisiologia , RNA Interferente Pequeno/genética , Serina-Treonina Quinases TOR/fisiologia
14.
Oncogene ; 31(2): 226-37, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21666718

RESUMO

MicroRNAs (miRNAs) are endogenous non-coding RNAs that are known to be involved in the pathogenesis of tumors. Gastric carcinoma (GC) is a common malignancy worldwide. The aim of this study was the identification of the expression signature and functional roles of aberrant miRNAs in GC. Initial screening established a profile of aberrantly expressed miRNAs in tumors. miR-370 was confirmed to be overexpressed in GC tissues. Higher expression of miR-370 in GC tissues was associated with more advanced nodal metastasis and a higher clinical stage compared with controls. In addition, significantly higher level of miR-370 was noted in the plasma of GC patients compared with controls. Patients having more invasive or advanced tumors also exhibited a higher plasma level of miR-370. In vitro assays indicated that exogenous miR-370 expression enhanced the oncogenic potential of GC cells. The AGS-GFPM2 cells with exogenous miR-370 expression also exhibited enhanced abdominal metastatic dissemination in nude mice. Reporter assays confirmed that miR-370 targeted predicted sites in 3'UTR of transforming growth factor-ß receptor II (TGFß-RII) gene. The exogenous miR-370 expression decreased TGFß-RII expression and the phosphorylation of Smad3 elicited by TGFß1. The TGFß1-mediated repression in cell migration was reverted by exogenous miR-370 expression. A reverse correlation between miR-370 and TGFß-RII expression was noted in GC tissues. This study concludes that miR-370 is a miRNA that is associated with GC progression by downregulating TGFß-RII. The miRNA expression profile described in this study should contribute to future studies on the role of miRNAs in GC.


Assuntos
MicroRNAs/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Neoplasias Gástricas/genética , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Receptor do Fator de Crescimento Transformador beta Tipo II , Neoplasias Gástricas/patologia
15.
Neuroscience ; 154(2): 461-72, 2008 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-18456416

RESUMO

Acid-sensing ion channels (ASICs), which are widely distributed in the mammalian brain, the spinal cord and the peripheral sensory organs, are ligand-gated cation channels activated by extracellular protons. Abundant experimental evidence shows that ASICs play important roles in physiological/pathological conditions, such as sensory transduction, learning/memory, retinal function, seizure and ischemia. In the auditory system, however, there are only a few studies available describing ASICs in hair cells, the spiral ganglion and the vestibular ganglion. In particular, functional ASICs have not been assessed in the central auditory region, although there is evidence to show their transcription in the inferior colliculus (IC). In the present study, we characterized ASIC-like currents in cultured IC neurons of rats with whole-cell patch-clamp techniques. A rapidly decaying inward current was induced by exogenous application of acidic solution in cultured IC neurons with a response threshold around pH 6.9 and a half activation pH value at 5.92. The current was sensitive to amiloride half-maximal inhibition concentration (IC50)=20.4+/-0.4 microM), an ASIC blocker, and its reversal potential was close to the theoretical Na+ equilibrium potential, indicating that the recorded current was mediated by ASICs. Further experiments revealed the presence of homomeric ASIC1a channels in IC neurons: (1) the ASIC-like current was partially carried by Ca2+ as demonstrated with an ion-substitution protocol and Ca2+ imaging; (2) the current was inhibited by the tarantula venom Psalmotoxin (PcTX1), a specific blocker for homomeric ASIC1a channels; (3) the current could be inhibited by extracellular Ca2+ (IC50=2.31 mM) and Pb2+ (10 microM), confirming the presence of ASIC1a subunit. The presence of functional ASIC2a containing channels was revealed by the Zn2+ (300 microM)-induced enhancement of ASIC-like currents and the absence of functional ASIC3 channels was indicated by the insensitivity of ASIC-like currents to salicylate (1 mM), an ASIC3 subunit blocker. Finally, we show that activation of ASICs by a pH drop could induce membrane depolarization and evoke neuronal firing in IC neurons. Our study clearly demonstrates that functional homomeric ASIC1a channels and ASIC2a-containing channels, but not ASIC3 channels, are present in the IC. We suggest that ASICs should be taken into consideration for their possible functional roles in information processing and pathological processes in the central auditory system.


Assuntos
Colículos Inferiores/fisiologia , Canais Iônicos/fisiologia , Neurônios/fisiologia , Ácidos/metabolismo , Amilorida/farmacologia , Animais , Animais Recém-Nascidos , Cálcio/metabolismo , Células Cultivadas , Diuréticos/farmacologia , Eletrofisiologia , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/fisiologia , Concentração de Íons de Hidrogênio , Colículos Inferiores/citologia , Colículos Inferiores/efeitos dos fármacos , Canais Iônicos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Peptídeos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Salicilatos/farmacologia , Sódio/metabolismo , Sódio/fisiologia , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/efeitos dos fármacos , Canais de Sódio/fisiologia , Venenos de Aranha/farmacologia
16.
Gene Ther ; 14(6): 484-90, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17093506

RESUMO

In this study, we explored the immunomodulatory effects of viral interleukin (IL) IL-10 after ex vivo and in vivo gene transfer in experimental corneal transplantation. Wistar-Furth rats were used as donors and major histocompatibility complex class I/II-disparate Lewis rats served as recipients. For ex vivo gene therapy donor corneas were either transfected with liposome/vIL-10 plasmid DNA mixtures or transduced with a vIL-10 expressing adenovirus vector (AdvIL-10). For in vivo studies, recipients were treated with AdvIL-10 intraperitoneally 1 day before transplantation. Graft survival was analysed using the Kaplan-Meier survival method. To monitor the efficacy of the therapy messenger RNA (mRNA) cytokine expression profiles in grafts and draining lymph nodes were analysed by quantitative real-time reverse transcription-polymerase chain reaction. Moreover, anti-adenovirus immunity was also investigated. Neither ex vivo liposome-mediated vIL-10 gene transfer nor ex vivo AdvIL-10 gene transfer led to prolonged corneal allograft survival. In contrast, corneal allograft survival was significantly prolonged in animals receiving systemic AdvIL-10 gene transfer. Moreover, only systemic vIL-10 gene therapy modulated the cytokine mRNA expression profile in draining lymph nodes. Interestingly, systemic AdvIL-10 gene transfer could not inhibit the generation of anti-adenovirus antibodies. Our data indicate systemic expression of the vIL-10 gene is required to modulate the cytokine expression profile in the draining lymph nodes, which might be a pre-requisite for the success of cytokine gene therapy.


Assuntos
Córnea/imunologia , Transplante de Córnea/métodos , Terapia Genética/métodos , Facilitação Imunológica de Enxerto , Interleucina-10/genética , Adenoviridae/genética , Animais , Anticorpos Antivirais/sangue , Feminino , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Sobrevivência de Enxerto , Injeções , Interleucina-10/imunologia , Lipossomos , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnicas de Cultura de Tecidos , Transdução Genética/métodos , Transfecção/métodos , Transplante Homólogo
17.
Transplant Proc ; 38(10): 3228-30, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175230

RESUMO

BACKGROUND: The aim of this study was to investigate the effects of adenovirus-mediated antisense ERK2 (Adanti-ERK2) gene therapy on chronic allograft nephropathy. METHODS: We employed a rat kidney transplantation mode (F344-->Lewis) and studied four groups: (1) controls (n = 6); (2) vector controls (n = 6); (3) an Adanti-ERK2 group (n = 10); and (4) an isograft group (n = 4). The animals were monitored for proteinuria, graft histology, infiltrating cells, and immune-related gene (interleukin-2 [IL-2] and intracellular adhesion molecule-1 [ICAM-1]) expression for 20 weeks after transplantation. RESULTS: The control group had increasing proteinuria during the 20-week follow-up. All rats showed advanced chronic renal failure associated with strong immune cell infiltration and immune gene expression. Chronic graft injury was accelerated in the vector-control group, but no significant difference was observed compared with the control group. In contrast, the Adanti-ERK2 group showed less inflammation and improved graft histology/function compared with controls. Moreover, ERK2 protein expression in the Adanti-ERK2 group was lower than in the control group (P < .05) and vector-control group (P < .05). Furthermore, serial estimates of genes (IL-2, ICAM-1) related to chronic rejection showed significant downregulation in the Adanti-ERK2 group (P < .01). CONCLUSIONS: Adenovirus-mediated antisense ERK2 gene therapy attenuated chronic allograft nephropathy. The protective effects of antisense ERK2 gene therapy may have derived from a blocked ERK signal transduction pathway, which reduced ERK expression as well as those of immune-related genes.


Assuntos
Adenoviridae/genética , Terapia Genética , Transplante de Rim/imunologia , Proteína Quinase 6 Ativada por Mitógeno/genética , Proteína Quinase 6 Ativada por Mitógeno/uso terapêutico , Transplante Homólogo/patologia , Animais , Sobrevivência de Enxerto/fisiologia , Transplante de Rim/patologia , Plasmídeos , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew
18.
Transplant Proc ; 38(10): 3304-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17175255

RESUMO

UNLABELLED: Chronic rejection is a major cause of transplant loss that is effected by the extracellular signal-regulated kinases (ERK) pathway. This study investigated the effects of antisense ERK1/2 oligodeoxynucleotide(ODN) gene therapy on chronic rejection. METHODS: Lewis (RT1(1)) rats served as recipients of Brown-Norway (BN, RT1n) grafts. The BN rat abdominal aortas were harvested and orthotopically grafted into Lewis rats. The recipients were divided into three groups: (1) control group (n = 9), (2) random ODN transfer group (n = 10), and (3) antisense ODN transfer group (n = 10). At day 60 after transplantation, the recipients were sacrificed; the grafted aortas were evaluated histologically and immunohistochemically. ERK1/2 protein expression in the grafts was determined using Western Blot assays. Serum levels of slCAM-1 were detected by ELISA. RESULTS: In the control group and random ODN transfer group, we observed a remarkable degree of intimal hyperplasia and inflammatory cell infiltration, including macrophages and T cells. Compared with the control group, antisense ERK1/2 ODN gene therapy resulted in a significant reduction in neointimal proliferation (P < .01), inhibition of ERK1/2 protein expression (P < .01), decreased graft infiltration with CD4+ T lymphocytes (P < .01), CD8+ T lymphocytes(P < .05), and ED-1 macrophages (P < .01) with decreased serum levels of sICAM-1 (P < .05). We obtained a negative correlation between ERK1/2 expression and immune cell infiltration or ICAM-1 level. CONCLUSIONS: Antisense ERK1/2 gene therapy can attenuate graft arteriosclerosis so as to protect aortic allografts. The protection seemed to correlate with inhibition of inflammatory infiltration, implying that the ERK1/2 signal transduction pathway plays an important role in the process of chronic vascular rejection.


Assuntos
Aorta Abdominal/transplante , Terapia Genética/métodos , Oligodesoxirribonucleotídeos Antissenso/uso terapêutico , Animais , Sequência de Bases , Primers do DNA , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Iniciação Traducional da Cadeia Peptídica , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Transplante Homólogo
19.
Neuroscience ; 141(1): 133-41, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-16675141

RESUMO

Neural inhibition in the brain is mainly mediated by ionotropic GABA type A receptors. Apart from the GABA type A receptors, both K(+)-Cl(-) cotransporter isoform 2 and the GABA-synthesizing enzyme, glutamic acid decarboxylase, are essential determinants for GABA type A receptor-mediated inhibition. By using immunofluorescent staining, we observed that K(+)-Cl(-) cotransporter isoform 2, GABA type A receptor beta2/3 subunits and a presynaptically localized glutamic acid decarboxylase isoform, glutamic acid decarboxylase 65, were all absent in adult Sprague-Dawley rat medial habenular nucleus, while immunopositive staining for glutamic acid decarboxylase 67, GABA and GABA type B receptor type 2 subunit were present in the medial habenular nucleus. Consistent with the lack of GABA type A signaling as detected by immunohistochemistry, GABA (100 muM) evoked no measurable currents in the medial habenular nucleus but induced bicuculline-sensitive currents in the lateral habenular nucleus and in the CA1 area of hippocampus. We also failed to record miniature inhibitory postsynaptic currents in medial habenular nucleus neurons. These results support the idea that GABAergic transmission in medial habenular nucleus is probably not mediated by any of the most common GABA type A receptor subtypes. Our data suggest that GABA type B receptor-mediated inhibition may play a role in balancing neuronal excitation in this special region. Further exploration for factors determining medial habenular nucleus neural inhibition will lead to a more complete understanding of control of synaptic balance in the CNS.


Assuntos
Habenula/citologia , Neurônios/fisiologia , Receptores de GABA-A/fisiologia , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Baclofeno/farmacologia , Bicuculina/farmacologia , Colina O-Acetiltransferase/metabolismo , Interações Medicamentosas , Antagonistas de Aminoácidos Excitatórios/farmacologia , Agonistas GABAérgicos/farmacologia , Antagonistas GABAérgicos/farmacologia , Glutamato Descarboxilase/metabolismo , Glicinérgicos/farmacologia , Imuno-Histoquímica/métodos , Técnicas In Vitro , Isoenzimas/metabolismo , Masculino , Inibição Neural/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Estricnina/farmacologia , Simportadores/metabolismo , Ácido gama-Aminobutírico/farmacologia , Cotransportadores de K e Cl-
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