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1.
Circ J ; 85(12): 2232-2240, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33678753

RESUMO

BACKGROUND: Sirt7 is a recently identified sirtuin and has important roles in various pathological conditions, including cancer progression and metabolic disorders. It has previously been reported that Sirt7 is a key molecule in acute myocardial wound healing and pressure overload-induced cardiac hypertrophy. In this study, the role of Sirt7 in neointimal formation after vascular injury is investigated.Methods and Results:Systemic (Sirt7-/-) and smooth muscle cell-specific Sirt7-deficient mice were subjected to femoral artery wire injury. Primary vascular smooth muscle cells (VSMCs) were isolated from the aorta of wild type (WT) and Sirt7-/-mice and their capacity for cell proliferation and migration was compared. Sirt7 expression was increased in vascular tissue at the sites of injury. Sirt7-/-mice demonstrated significant reduction in neointimal formation compared to WT mice. In vitro, Sirt7 deficiency attenuated the proliferation of serum-induced VSMCs. Serum stimulation-induced upregulation of cyclins and cyclin-dependent-kinase 2 (CDK2) was significantly attenuated in VSMCs of Sirt7-/-compared with WT mice. These changes were accompanied by enhanced expression of the microRNA 290-295 cluster, the translational negative regulator of CDK2, in VSMCs of Sirt7-/-mice. It was confirmed that smooth muscle cell-specific Sirt7-deficient mice showed significant reduction in neointima compared with control mice. CONCLUSIONS: Sirt7 deficiency attenuates neointimal formation after vascular injury. Given the predominant role in vascular neointimal formation, Sirt7 is a potentially suitable target for treatment of vascular diseases.


Assuntos
Sirtuínas , Lesões do Sistema Vascular , Animais , Movimento Celular , Proliferação de Células/fisiologia , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Neointima/patologia , Sirtuínas/genética , Sirtuínas/metabolismo , Lesões do Sistema Vascular/genética
2.
Mol Cell Neurosci ; 108: 103535, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32758699

RESUMO

Epilepsy is among the most common neurological disorders, affecting approximately 50 million people worldwide. Importantly, epilepsy is genetically and etiologically heterogenous, but several epilepsy types exhibit similar clinical presentations. Epilepsy-associated genes are being identified. However, the molecular pathomechanisms remain largely unknown. Approximately one-third of epilepsy is refractory to multiple conventional anti-epileptic drugs (AEDs). Induced pluripotent stem cells (iPSCs) provide an excellent tool to study the pathomechanisms underlying epilepsy and to develop novel treatments. Indeed, disease-specific iPSCs have been established for several genetic epilepsies. In particular, the molecular mechanisms underlying certain developmental and epileptic encephalopathies, such as Dravet syndrome, have been revealed. Modeling epilepsy with iPSCs enables new drug development based on the elucidated pathomechanisms. This can also be used to evaluate conventional AEDs and drug repurposing. Furthermore, transplanting neuronal cells derived from iPSCs into the brain has great potential to treat refractory epilepsies. Recent advances in iPSC technology have enabled the generation of neuronal organoids, or "mini brains." These organoids demonstrate electrophysiological activities similar to those of the brain and have the potential for extensive epilepsy research opportunities. Thus, the application of iPSCs in epilepsy provides insight into novel treatments based on the molecular pathomechanisms of epilepsy. In this review, we comprehensively discuss the studies conducted on iPSCs established for genetic epilepsy or epilepsies without major structural dysmorphic features.


Assuntos
Anticonvulsivantes/farmacologia , Epilepsia/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Epilepsia/genética , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos
3.
Parasitology ; 147(14): 1765-1773, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32943118

RESUMO

The duognathous haemadipsid leeches of the genus Chtonobdella show a trans-oceanic distribution throughout the Indo-Pacific region. Although passive long-distance dispersal (LDD) of Chtonobdella leeches by birds has been suggested, little is known about the host-parasite relationships between avian hosts and Chtonobdella leeches. In the current study, we investigated Chtonobdella leech infestations of the eyes and other mucus membranes of migratory procellariiform seabirds, Pterodroma hypoleuca and Oceanodroma tristrami, captured at six locations in the Bonin Islands, Honshu and Okinawa Island, Japan. Analyses of the partial sequences of 18S rRNA, 28S rRNA, and mitochondrial cytochrome c oxidase subunit I (COI) and morphological examination of the specimens demonstrated that the Chtonobdella leeches belonged to Chtonobdella palmyrae, which is indigenous to Palmyra Atoll in the Northern Line Islands. A dominant COI sequence type was observed in samples from all six sites; therefore, C. palmyrae almost surely dispersed approximately 1000 km by infesting the eyes and mucus membranes of procellariiform seabirds. The host-parasite relationships between procellariiform seabirds and C. palmyrae provide explicit evidence of the LDD of duognathous haemadipsid leeches. The taxonomic status of Haemadipsa zeylanica ivosimae from the Volcano Islands is also briefly discussed.


Assuntos
Aves , Helmintíase Animal/parasitologia , Interações Hospedeiro-Parasita , Sanguessugas/fisiologia , Animais , Ilhas , Japão
4.
BMC Med Imaging ; 20(1): 15, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041550

RESUMO

BACKGROUND: The Logan graphical analysis (LGA) algorithm is widely used to quantify receptor density for parametric imaging in positron emission tomography (PET). Estimating receptor density, in terms of the non-displaceable binding potential (BPND), from the LGA using the ordinary least-squares (OLS) method has been found to be negatively biased owing to noise in PET data. This is because OLS does not consider errors in the X-variable (predictor variable). Existing bias reduction methods can either only reduce the bias slightly or reduce the bias accompanied by increased variation in the estimates. In this study, we addressed the bias reduction problem by applying a different regression method. METHODS: We employed least-squares cubic (LSC) linear regression, which accounts for errors in both variables as well as the correlation of these errors. Noise-free PET data were simulated, for 11C-carfentanil kinetics, with known BPND values. Statistical noise was added to these data and the BPNDs were re-estimated from the noisy data by three methods, conventional LGA, multilinear reference tissue model 2 (MRTM2), and LSC-based LGA; the results were compared. The three methods were also compared in terms of beta amyloid (A ß) quantification of 11C-Pittsburgh compound B brain PET data for two patients with Alzheimer's disease and differing A ß depositions. RESULTS: Amongst the three methods, for both synthetic and actual data, LSC was the least biased, followed by MRTM2, and then the conventional LGA, which was the most biased. Variations in the LSC estimates were smaller than those in the MRTM2 estimates. LSC also required a shorter computational time than MRTM2. CONCLUSIONS: The results suggest that LSC provides a better trade-off between the bias and variability than the other two methods. In particular, LSC performed better than MRTM2 in all aspects; bias, variability, and computational time. This makes LSC a promising method for BPND parametric imaging in PET studies.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/química , Isótopos de Carbono/farmacocinética , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Viés , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Isótopos de Carbono/química , Fentanila/análogos & derivados , Fentanila/química , Humanos , Análise dos Mínimos Quadrados , Tomografia por Emissão de Pósitrons , Razão Sinal-Ruído
5.
Skin Res Technol ; 26(6): 891-897, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32585082

RESUMO

BACKGROUND: Melanoma is a type of superficial tumor. As advanced melanoma has a poor prognosis, early detection and therapy are essential to reduce melanoma-related deaths. To that end, there is a need to develop a quantitative method for diagnosing melanoma. This paper reports the development of such a diagnostic system using hyperspectral data (HSD) and a convolutional neural network, which is a type of machine learning. MATERIALS AND METHODS: HSD were acquired using a hyperspectral imager, which is a type of spectrometer that can simultaneously capture information about wavelength and position. GoogLeNet pre-trained with Imagenet was used to model the convolutional neural network. As many CNNs (including GoogLeNet) have three input channels, the HSD (involving 84 channels) could not be input directly. For that reason, a "Mini Network" layer was added to reduce the number of channels from 84 to 3 just before the GoogLeNet input layer. In total, 619 lesions (including 278 melanoma lesions and 341 non-melanoma lesions) were used for training and evaluation of the network. RESULTS AND CONCLUSION: The system was evaluated by 5-fold cross-validation, and the results indicate sensitivity, specificity, and accuracy of 69.1%, 75.7%, and 72.7% without data augmentation, 72.3%, 81.2%, and 77.2% with data augmentation, respectively. In future work, it is intended to improve the Mini Network and to increase the number of lesions.


Assuntos
Melanoma , Redes Neurais de Computação , Humanos , Aprendizado de Máquina , Melanoma/diagnóstico por imagem , Análise Espectral
6.
Skin Res Technol ; 25(3): 318-324, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30600563

RESUMO

BACKGROUND: We tried to search appropriate wavelength to quantitatively evaluate the ability of long-lasting foundation using a hyperspectral imager (HSI) which can simultaneously measure position and wavelength information. MATERIALS AND METHODS: A good reputable long-lasting foundation was applied to the skin of 10 healthy volunteers. Their skin was measured by our newly developed HSI every 2 hours from immediately after application to 6 hours. The application state of the foundation was quantified using the standard deviation of reflectance. RESULTS: A high correlation between standard deviation and the application state of the foundation was confirmed at many wavelengths. In particular, it was suggested that by using the standard deviation of 800 nm, the application state of the foundation can be evaluated quantitatively without depending on the subject's oxygen saturation level. CONCLUSION: By quantitatively evaluating the cosmetic-applied skin by our system, further efficiency improvement of the volunteer experiment is expected.


Assuntos
Cosméticos , Análise Espectral/métodos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Teste de Materiais , Pele , Análise Espectral/instrumentação , Fatores de Tempo , Adulto Jovem
7.
J Virol ; 91(11)2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28331087

RESUMO

The interplay between viral and host proteins has been well studied to elucidate virus-host interactions and their relevance to virulence. Mammalian genes encode apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3) proteins, which act as intrinsic restriction factors against lentiviruses. To overcome APOBEC3-mediated antiviral actions, lentiviruses have evolutionarily acquired an accessory protein, viral infectivity factor (Vif), and Vif degrades host APOBEC3 proteins via a ubiquitin/proteasome-dependent pathway. Although the Vif-APOBEC3 interaction and its evolutionary significance, particularly those of primate lentiviruses (including HIV) and primates (including humans), have been well investigated, those of nonprimate lentiviruses and nonprimates are poorly understood. Moreover, the factors that determine lentiviral pathogenicity remain unclear. Here, we focus on feline immunodeficiency virus (FIV), a pathogenic lentivirus in domestic cats, and the interaction between FIV Vif and feline APOBEC3 in terms of viral virulence and evolution. We reveal the significantly reduced diversity of FIV subtype B compared to that of other subtypes, which may associate with the low pathogenicity of this subtype. We also demonstrate that FIV subtype B Vif is less active with regard to feline APOBEC3 degradation. More intriguingly, we further reveal that FIV protease cleaves feline APOBEC3 in released virions. Taken together, our findings provide evidence that a lentivirus encodes two types of anti-APOBEC3 factors, Vif and viral protease.IMPORTANCE During the history of mammalian evolution, mammals coevolved with retroviruses, including lentiviruses. All pathogenic lentiviruses, excluding equine infectious anemia virus, have acquired the vif gene via evolution to combat APOBEC3 proteins, which are intrinsic restriction factors against exogenous lentiviruses. Here we demonstrate that FIV, a pathogenic lentivirus in domestic cats, antagonizes feline APOBEC3 proteins by both Vif and a viral protease. Furthermore, the Vif proteins of an FIV subtype (subtype B) have attenuated their anti-APOBEC3 activity through evolution. Our findings can be a clue to elucidate the complicated evolutionary processes by which lentiviruses adapt to mammals.


Assuntos
Desaminases APOBEC/antagonistas & inibidores , Ácido Aspártico Endopeptidases/metabolismo , Produtos do Gene vif/metabolismo , Vírus da Imunodeficiência Felina/genética , Desaminases APOBEC/metabolismo , Animais , Ácido Aspártico Endopeptidases/genética , Gatos , Evolução Molecular , Produtos do Gene vif/genética , Interações Hospedeiro-Patógeno , Vírus da Imunodeficiência Felina/metabolismo , Vírus da Imunodeficiência Felina/patogenicidade , Virulência
8.
Circ J ; 82(11): 2905-2912, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30101817

RESUMO

BACKGROUND: Resistance exercise has beneficial effects for patients with peripheral arterial diseases. The hypothesis that muscle growth promotes angiogenesis by interacting with neighboring cells in ischemic lesions was assessed. Methods and Results: Skeletal muscle-specific inducible Akt1 transgenic (Akt1-TG) mice that induce growth of functional skeletal muscles as a model of resistance training were used. Proteomics analysis identified significant upregulation of heme oxigenase-1 (HO-1) in muscle tissue in Akt1-TG mice compared with control mice. Blood flow recovery after hindlimb ischemia was significantly increased in Akt1-TG mice compared with control mice. Enhanced blood flow and capillary density in Akt1-TG mice were completely abolished by the HO-1 inhibitor, Tin-mesoporphyrin. Immunohistochemistry showed that HO-1 expression was not increased in muscle cells, but it was increased in macrophages and endothelial cells. Consistent with these findings, blood flow recovery after hindlimb ischemia was similar between control mice and skeletal muscle-specific HO-1-knockout mice. Adenoviral-mediated overexpression of Akt1 did not increase HO-1 protein expression in C2C12 myotubes; however, the conditioned medium from Akt1-overexpressing C2C12 myotubes increased HO-1 expression in endothelial cells. Cytokine array demonstrated that a panel of cytokine secretion was upregulated in Akt1-overexpressing C2C12 cells, suggesting paracrine interaction between muscle cells and endothelial cells and macrophages. CONCLUSIONS: Akt1-mediated muscle growth improves blood flow recovery after hindlimb ischemia by enhancing HO-1 expression in neighboring cells.


Assuntos
Células Endoteliais/enzimologia , Heme Oxigenase-1/metabolismo , Membro Posterior , Isquemia/enzimologia , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Velocidade do Fluxo Sanguíneo , Linhagem Celular , Células Endoteliais/patologia , Heme Oxigenase-1/genética , Membro Posterior/irrigação sanguínea , Membro Posterior/enzimologia , Membro Posterior/patologia , Isquemia/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/enzimologia , Músculo Esquelético/patologia , Proteínas Proto-Oncogênicas c-akt/genética
9.
Synapse ; 71(8)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28407307

RESUMO

Adenosine A1 receptors (A1 Rs) interact negatively with dopamine D1 receptors (D1 Rs) in neurons of the basal ganglia's direct pathway, while adenosine A2A receptors (A2A Rs) negatively interact with dopamine D2 receptors (D2 Rs) in indirect-pathway neurons. The aim of this study was to investigate the cerebral density of A1 Rs in Parkinson's disease (PD) in its early stages, using PET scans with the radioligand 8-dicyclopropylmethyl-1-11 C-methyl-3-propylxanthine (11 C-MPDX). We studied 10 drug-naïve patients with early PD. Each patient was also examined for dopamine transporters (DATs) and D2 Rs by PET using 11 C-2-ß-carbomethoxy-3-ß-(4-fluorophenyl)-tropane (11 C-CFT) and 11 C-raclopride (11 C-RAC), respectively. Ten elderly, healthy volunteers were recruited as controls for 11 C-MPDX PET scanning and eight elderly volunteers were recruited as controls for 11 C-CFT and 11 C-RAC PET scanning. The PET scans revealed a decrease in the uptake ratio index (URI) of 11 C-CFT and an increase in the URI of 11 C-RAC in patients. In the temporal lobe, the binding potential for 11 C-MPDX was higher in the patient group than in healthy subjects, but not in the other regions examined, including the striatum. In patients, we observed motor-symptom asymmetry and a relationship between parkinsonism and the striatal density of DATs, but not A1 R density. In the putamen of early PD, asymmetrical down-regulation of A2A Rs is likely a compensatory mechanism in response to a decrease in dopamine. However, our study suggests that A1 Rs are unaltered in the putamen of early PD.


Assuntos
Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Receptor A1 de Adenosina/metabolismo , Xantinas , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Mapeamento Encefálico , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Racloprida , Receptores de Dopamina D2/metabolismo , Tropanos
10.
Heart Vessels ; 32(6): 708-713, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27882404

RESUMO

Wild-type transthyretin amyloidosis (ATTRwt) is often overlooked in elderly patients with left ventricular hypertrophy (LVH). Impaired atrial function, in addition to ventricular diastolic dysfunction, is one of the hallmarks of cardiac amyloidosis. Here, we assessed the hypothesis that atrial function evaluated by A-velocity in pulse Doppler echocardiography is useful to differentiate ATTRwt in elderly patients with LVH. We analyzed 133 consecutive patients who underwent tissue biopsy to rule out infiltrative cardiomyopathy in our institute. We excluded patients younger than 50 years, without LVH (LV thickness was less than 12 mm), with other types of cardiac amyloidosis and patients with chronic atrial fibrillation, and analyzed remaining 51 patients (ATTRwt: 16, non-ATTRwt: 35). ATTRwt patients were significantly older and had advanced heart failure compared with non-ATTRwt group. In echocardiography, E/A, E/e', and relative wall thickness was significantly higher in ATTRwt group than non-ATTRwt group. A-velocity was significantly decreased in ATTRWT group compared with non-ATTRwt group (40.8 ± 20.8 vs. 78.7 ± 28.2 cm/s, p = 0.0001). Multivariate logistic analysis using eight forced inclusion models identified trans-mitral Doppler A-wave velocity was more significant factor of cardiac amyloidosis in ATTRwt. In receiver operating characteristic (ROC) analysis, the area under the curve (AUC) for A-wave velocity in discrimination between ATTRwt and non-ATTRwt were 0.86 (CI 0.76-0.96, p < 0.001). The cut-off value was 62.5 cm/s, and it yielded the best combination of sensitivity (69.7%) and specificity (87.5%) for prediction of amyloidosis. We concluded that reduced A-velocity predicts the presence of ATTRwt in elderly patients with LVH in sinus rhythm.


Assuntos
Neuropatias Amiloides Familiares/complicações , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Neuropatias Amiloides Familiares/diagnóstico por imagem , Neuropatias Amiloides Familiares/patologia , Ecocardiografia Doppler , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etiologia , Japão/epidemiologia , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Onda de Pulso , Curva ROC , Estudos Retrospectivos
11.
Circulation ; 132(12): 1081-93, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26202810

RESUMO

BACKGROUND: Sirt7, 1 of the 7 members of the mammalian sirtuin family, promotes oncogenic transformation. Tumor growth and metastasis require fibrotic and angiogenic responses. Here, we investigated the role of Sirt7 in cardiovascular tissue repair process. METHODS AND RESULTS: In wild-type mice, Sirt7 expression increased in response to acute cardiovascular injury, including myocardial infarction and hind-limb ischemia, particularly at the active wound healing site. Compared with wild-type mice, homozygous Sirt7-deficient (Sirt7(-/-)) mice showed susceptibility to cardiac rupture after myocardial infarction, delayed blood flow recovery after hind-limb ischemia, and impaired wound healing after skin injury. Histological analysis showed reduced fibrosis, fibroblast differentiation, and inflammatory cell infiltration in the border zone of infarction in Sirt7(-/-) mice. In vitro, Sirt7(-/-) mouse-derived or Sirt7 siRNA-treated cardiac fibroblasts showed reduced transforming growth factor-ß signal activation and low expression levels of fibrosis-related genes compared with wild-type mice-derived or control siRNA-treated cells. These changes were accompanied by reduction in transforming growth factor receptor I protein. Loss of Sirt7 activated autophagy in cardiac fibroblasts. Transforming growth factor-ß receptor I downregulation induced by loss of Sirt7 was blocked by autophagy inhibitor, and interaction of Sirt7 with protein interacting with protein kinase-Cα was involved in this process. CONCLUSION: Sirt7 maintains transforming growth factor receptor I by modulating autophagy and is involved in the tissue repair process.


Assuntos
Fibroblastos/efeitos dos fármacos , Coração/fisiologia , Neovascularização Fisiológica/fisiologia , Regeneração/fisiologia , Transdução de Sinais/fisiologia , Sirtuínas/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Animais , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças , Fibroblastos/patologia , Membro Posterior/irrigação sanguínea , Técnicas In Vitro , Isquemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/fisiopatologia , RNA Interferente Pequeno/farmacologia , Sirtuínas/deficiência , Sirtuínas/genética , Cicatrização/fisiologia
12.
PLoS Pathog ; 10(10): e1004453, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25330146

RESUMO

Several APOBEC3 proteins, particularly APOBEC3D, APOBEC3F, and APOBEC3G, induce G-to-A hypermutations in HIV-1 genome, and abrogate viral replication in experimental systems, but their relative contributions to controlling viral replication and viral genetic variation in vivo have not been elucidated. On the other hand, an HIV-1-encoded protein, Vif, can degrade these APOBEC3 proteins via a ubiquitin/proteasome pathway. Although APOBEC3 proteins have been widely considered as potent restriction factors against HIV-1, it remains unclear which endogenous APOBEC3 protein(s) affect HIV-1 propagation in vivo. Here we use a humanized mouse model and HIV-1 with mutations in Vif motifs that are responsible for specific APOBEC3 interactions, DRMR/AAAA (4A) or YRHHY/AAAAA (5A), and demonstrate that endogenous APOBEC3D/F and APOBEC3G exert strong anti-HIV-1 activity in vivo. We also show that the growth kinetics of 4A HIV-1 negatively correlated with the expression level of APOBEC3F. Moreover, single genome sequencing analyses of viral RNA in plasma of infected mice reveal that 4A HIV-1 is specifically and significantly diversified. Furthermore, a mutated virus that is capable of using both CCR5 and CXCR4 as entry coreceptor is specifically detected in 4A HIV-1-infected mice. Taken together, our results demonstrate that APOBEC3D/F and APOBEC3G fundamentally work as restriction factors against HIV-1 in vivo, but at the same time, that APOBEC3D and APOBEC3F are capable of promoting viral diversification and evolution in vivo.


Assuntos
Citidina Desaminase/metabolismo , Citosina Desaminase/metabolismo , HIV-1 , Mutação/genética , RNA Viral/genética , Animais , Evolução Biológica , Mapeamento Cromossômico , Modelos Animais de Doenças , Variação Genética/genética , Humanos , Camundongos , Receptores CXCR4/genética , Replicação Viral/fisiologia
13.
Heart Vessels ; 31(1): 52-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25150586

RESUMO

Thrombospondin-2 (TSP-2) is highly expressed in hypertensive heart. Interstitial fibrosis is frequently observed in hypertensive heart, and it is a characteristic feature of heart failure with preserved ejection fraction (HFpEF). We tested here the hypothesis that high TSP-2 serum levels reflect disease severity and can predict poor prognosis of patients with HFpEF. Serum TSP-2 levels were measured by ELISA in 150 patients with HFpEF. HFpEF was defined as left ventricular ejection fraction ≥ 50%, B-type natriuretic peptide (BNP) ≥ 100 pg/ml or E/e' ≥ 15. The endpoints were mortality rate, HF-related hospitalization, stroke and non-fatal myocardial infarction. The median serum TSP-2 level was 19.2 (14.4-26.0) ng/ml. Serum TSP-2 levels were associated with the New York Heart Association (NYHA) functional class. Circulating levels of BNP and high-sensitivity troponin T were positively correlated with serum TSP-2 levels. Kaplan-Meier survival curve showed high risk of adverse cardiovascular events in the high TSP-2 group (>median value), and that the combination of high TSP-2 and high BNP (≥ 100 pg/ml) was associated with the worst event-free survival rate. Multivariate Cox proportional hazard analysis identified TSP-2 as independent predictor of risk of death and cardiovascular events. Circulating TSP-2 correlates with disease severity in patients with HFpEF. TSP-2 is a potentially useful predictor of future adverse cardiovascular events in patients with HFpEF.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Peptídeo Natriurético Encefálico/sangue , Volume Sistólico , Trombospondinas/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Intervalo Livre de Doença , Feminino , Humanos , Japão , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Função Ventricular Esquerda
14.
Heart Vessels ; 31(4): 563-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25712607

RESUMO

Fragmented QRS complex (fQRS) on 12-lead ECG is associated with myocardial fibrosis and ischemic scar. Interstitial fibrosis is one of the histological characteristics of left ventricular diastolic dysfunction (LVDD). However, the clinical importance of fQRS in patients with LVDD remains unclear. Here, we assessed the hypothesis that the presence of fQRS is associated with disease severity in patients with LVDD, and could be used as an additional parameter to differentiate patients with heart failure with preserved ejection fraction (HFpEF) from LVDD. We analyzed 12-lead ECG of 239 patients with LVDD. The patients were divided into two groups according to the presence or absence of fQRS; 88 patients had fQRS (fQRS group) and 151 patients did not have fQRS (non-fQRS group). The percentage of patients with heart failure in the fQRS group was significantly higher than that in the non-fQRS group. The levels of B-type natriuretic peptide (BNP) and high-sensitive troponin T were significantly higher in the fQRS group than those in the non-fQRS group. In univariate logistic regression analysis, fQRS was associated with the presence of heart failure in patients with LVDD. Multivariate logistic regression analysis identified fQRS and BNP as independent indicators for HFpEF. In conclusion, the presence of fQRS on the ECG could be used as an additional tool to differentiate HFpEF from LVDD.


Assuntos
Eletrocardiografia , Ventrículos do Coração/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico , Função Ventricular Esquerda/fisiologia , Idoso , Diagnóstico Diferencial , Diástole , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Disfunção Ventricular Esquerda/fisiopatologia
15.
J Virol ; 88(10): 5881-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24623435

RESUMO

APOBEC3F and APOBEC3G cytidine deaminases potently inhibit human immunodeficiency virus type 1 (HIV-1) replication by enzymatically inserting G-to-A mutations in viral DNA and/or impairing viral reverse transcription independently of their deaminase activity. Through experimental and mathematical investigation, here we quantitatively demonstrate that 99.3% of the antiviral effect of APOBEC3G is dependent on its deaminase activity, whereas 30.2% of the antiviral effect of APOBEC3F is attributed to deaminase-independent ability. This is the first report quantitatively elucidating how APOBEC3F and APOBEC3G differ in their anti-HIV-1 modes.


Assuntos
Citidina Desaminase/metabolismo , Citosina Desaminase/metabolismo , HIV-1/imunologia , HIV-1/fisiologia , Interações Hospedeiro-Patógeno , Replicação Viral , Desaminase APOBEC-3G , Linhagem Celular , Humanos , Modelos Teóricos
16.
J Am Soc Nephrol ; 25(12): 2800-11, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25012168

RESUMO

Muscle wasting is frequently observed in patients with kidney disease, and low muscle strength is associated with poor outcomes in these patients. However, little is known about the effects of skeletal muscle growth per se on kidney diseases. In this study, we utilized a skeletal muscle-specific, inducible Akt1 transgenic (Akt1 TG) mouse model that promotes the growth of functional skeletal muscle independent of exercise to investigate the effects of muscle growth on kidney diseases. Seven days after Akt1 activation in skeletal muscle, renal injury was induced by unilateral ureteral obstruction (UUO) in Akt1 TG and wild-type (WT) control mice. The expression of atrogin-1, an atrophy-inducing gene in skeletal muscle, was upregulated 7 days after UUO in WT mice but not in Akt1 TG mice. UUO-induced renal interstitial fibrosis, tubular injury, apoptosis, and increased expression of inflammatory, fibrosis-related, and adhesion molecule genes were significantly diminished in Akt1 TG mice compared with WT mice. An increase in the activating phosphorylation of eNOS in the kidney accompanied the attenuation of renal damage by myogenic Akt1 activation. Treatment with the NOS inhibitor L-NAME abolished the protective effect of skeletal muscle Akt activation on obstructive kidney disease. In conclusion, Akt1-mediated muscle growth reduces renal damage in a model of obstructive kidney disease. This improvement appears to be mediated by an increase in eNOS signaling in the kidney. Our data support the concept that loss of muscle mass during kidney disease can contribute to renal failure, and maintaining muscle mass may improve clinical outcome.


Assuntos
Músculo Esquelético/metabolismo , Atrofia Muscular/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Insuficiência Renal/fisiopatologia , Adiponectina/sangue , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Fibrose/patologia , Glicólise , Inflamação , Rim/metabolismo , Rim/patologia , Camundongos , Camundongos Transgênicos , Proteínas Musculares/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/patologia , Músculos/patologia , Miofibroblastos/citologia , NG-Nitroarginina Metil Éster/química , Óxido Nítrico Sintase/antagonistas & inibidores , Condicionamento Físico Animal , Proteínas Ligases SKP Culina F-Box/metabolismo
17.
Circ J ; 78(4): 903-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24500070

RESUMO

BACKGROUND: Thrombospondin-2 (TSP-2) is a matricellular protein found in human serum. Deletion of TSP-2 causes age-dependent dilated cardiomyopathy. We hypothesized that TSP-2 is a useful biomarker in patients with heart failure with reduced ejection fraction (HFrEF). METHODS AND RESULTS: Serum TSP-2 was measured in 101 patients with HFrEF, and mortality and cardiovascular events were followed. Serum TSP-2 in the HFrEF group was significantly higher than in the non-HF group (n=17). Mean NYHA functional class was significantly higher in the high TSP-2 group (>median) than the low TSP-2 group (2.26 vs. 1.76, P=0.004). Circulating TSP-2 level was significantly associated with that of B-type natriuretic peptide (BNP; r=0.40, P<0.0001) on multivariate linear regression analysis. On Kaplan-Meier curve analysis the high TSP-2 group had a lower event-free rate than the low TSP-2 group (log-rank test, P=0.03). Multivariate Cox hazard analysis identified hemoglobin (hazard ratio [HR], 0.66; 95% confidence interval [CI]: 0.53-0.82, P<0.0001), and TSP-2 (ln[TSP-2]; HR, 3.34; 95% CI: 1.03-10.85, P=0.045) as independent predictors of adverse outcome. The area under the curve for 1-year events increased when TSP-2 was added to Framingham risk score (FRS; alone, 0.60) or BNP (alone, 0.69; FRS+TSP-2, 0.75; BNP+TSP-2, 0.76). CONCLUSIONS: TSP-2 is a potentially useful biomarker for assessment of disease severity and prognosis in HFrEF.


Assuntos
Insuficiência Cardíaca , Índice de Gravidade de Doença , Volume Sistólico , Trombospondinas/sangue , Idoso , Biomarcadores/sangue , Intervalo Livre de Doença , Seguimentos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Valor Preditivo dos Testes , Taxa de Sobrevida
18.
Eukaryot Cell ; 12(6): 864-74, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23563484

RESUMO

The Saccharomyces cerevisiae Pbp1 [poly(A)-binding protein (Pab1)-binding protein] is believed to be involved in RNA metabolism and regulation of translation, since Pbp1 regulates a length of poly(A) tail and is involved in stress granule (SG) formation. However, a physiological function of Pbp1 remains unclear, since the pbp1Δ mutation has no obvious effect on cell growth. In this study, we showed that PBP1 genetically interacts with CCR4 and KHD1, which encode a cytoplasmic deadenylase and an RNA-binding protein, respectively. Ccr4 and Khd1 modulate a signal from Rho1 in the cell wall integrity pathway by regulating the expression of RhoGEF and RhoGAP, and the double deletion of CCR4 and KHD1 confers a severe growth defect displaying cell lysis. We found that the pbp1Δ mutation suppressed the growth defect caused by the ccr4Δ khd1Δ mutation. The pbp1Δ mutation also suppressed the growth defect caused by double deletion of POP2, encoding another cytoplasmic deadenylase, and KHD1. Deletion of the gene encoding previously known Pbp1-interacting factor Lsm12, Pbp4, or Mkt1 did not suppress the growth defect of the ccr4Δ khd1Δ mutant, suggesting that Pbp1 acts independently of these factors in this process. We then screened novel Pbp1-interacting factors and found that Pbp1 interacts with ribosomal proteins Rpl12a and Rpl12b. Similarly to the pbp1Δ mutation, the rpl12aΔ and rpl12bΔ mutations also suppressed the growth defect caused by the ccr4Δ khd1Δ mutation. Our results suggest that Pbp1 is involved in the Ccr4- and Khd1-mediated regulation of cell growth through the association with Rpl12a and Rpl12b.


Assuntos
Proteínas de Transporte/genética , Regulação Fúngica da Expressão Gênica , Ribonucleases/genética , Ribonucleoproteínas/genética , Proteínas Ribossômicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Proteínas de Transporte/metabolismo , Escherichia coli/genética , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Ribonucleases/deficiência , Ribonucleoproteínas/deficiência , Proteínas Ribossômicas/deficiência , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais
19.
Electromagn Biol Med ; 33(4): 327-34, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24131393

RESUMO

Plants growing in natural environments are exposed to radiofrequency electromagnetic radiation (EMR) emitted by various communication network base stations. The environmental concentration of this radiation is increasing rapidly with the congested deployment of base stations. Although numerous scientific studies have been conducted to investigate the effects of EMR on the physiology of humans and animals, there have been few attempts to investigate the effects of EMR on plants. In this study, we attempted to evaluate the effects of EMR on photosynthesis by investigating the chlorophyll fluorescence (ChF) parameters of duckweed fronds. During the experiment, the fronds were tested with 2, 2.5, 3.5, 5.5 and 8 GHz EMR frequencies, which are not widely studied even though there is a potentially large concentration of these frequencies in the environment. The duckweed fronds were exposed to EMR for 30 min, 1 h and 24 h durations with electric field strength of 45-50 V/m for each frequency. The results indicated that exposure to EMR causes a change in the non-photochemical quenching of the duckweeds. The changes varied with the frequency of the EMR and were time-varying within a particular frequency. The temperature remained unchanged in the duckweed fronds upon exposure to EMR, which confirms that the effect is non-thermal.


Assuntos
Araceae/metabolismo , Araceae/efeitos da radiação , Clorofila/química , Ondas de Rádio/efeitos adversos , Clorofila/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Espectrometria de Fluorescência , Fatores de Tempo , Tecnologia sem Fio
20.
J Neuroeng Rehabil ; 10: 118, 2013 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-24370075

RESUMO

BACKGROUND: Root mean square (RMS) of trunk acceleration is seen frequently in gait analysis research. However, many studies have reported that the RMS value was related to walking speed. Therefore, the relationship between the RMS value and walking speed should be considered when the RMS value is used to assess gait abnormality. We hypothesized that the RMS values in three sensing axes exhibit common proportions for healthy people if they walk at their own preferred speed and that the RMS proportions in abnormal gait deviate from the common proportions. In this study, we proposed the RMS ratio (RMSR) as a gait abnormality measure and verified its ability to discriminate abnormal gait. METHODS: Forty-seven healthy male subjects (24-49 years) were recruited to examine the relationship between walking speed and the RMSR. To verify its ability to discriminate abnormal gait, twenty age-matched male hemiplegic patients (30-48 years) participated as typical subjects with gait abnormality. A tri-axial accelerometer was attached to their lower back, and they walked along a corridor at their own preferred speed. We defined the RMSR as the ratio between RMS in each direction and the RMS vector magnitude. RESULTS: In the healthy subjects, the RMS in all directions related to preferred walking speed. In contrast, RMSR in the mediolateral (ML) direction did not correlate with preferred walking speed (rs = -0.10, p = 0.54) and represented the similar value among the healthy subjects. Moreover, the RMSR in the ML direction for the hemiplegic patients was significantly higher than that for the healthy subjects (p < 0.01). CONCLUSIONS: These results suggest that the RMSR in the ML direction exhibits a common value when healthy subjects walk at their own preferred speed, even if their preferred walking speed were different. For subjects with gait abnormality, the RMSR in the ML direction deviates from the common value of healthy subjects. The RMSR in the ML direction may potentially be a quantitative measure of gait abnormality.


Assuntos
Transtornos Neurológicos da Marcha/diagnóstico , Marcha/fisiologia , Modelos Estatísticos , Aceleração , Adulto , Fenômenos Biomecânicos , Humanos , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural , Tronco , Caminhada , Adulto Jovem
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