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1.
Horm Metab Res ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39333044

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor agonists are effective hypoglycemic agents for type 2 diabetes mellitus (T2DM). It was reported that T2DM was implicated in pancreatic ß-cell senescence. Whether loxenatide regulates cellular senescence of pancreatic ß-cells is to be investigated. Our results revealed that high glucose (HG)-induced cellular senescence and elevated expression of SASP factors inhibited cell proliferation and stimulated DNA damage, which were reversed by loxenatide treatment. In addition, HG induction resulted in promoted insulin secretion and insulin synthesis of pancreatic ß-cells and loxenatide treatment further strengthened these influences. In addition, loxenatide could inactivate the PERK/eIF2α signaling pathway via decreasing the levels of p-PERK and p-eIF2α in HG-induced pancreatic ß-cells. Furthermore, CCT020312, an activator of the PERK/eIF2α signaling pathway, abolished loxenatide-mediated inhibiting cellular senescence, elevating cell proliferation and improving DNA damage and enhancing insulin secretion of HG-induced pancreatic ß-cells. In conclusion, our results indicated that loxenatide impeded cellular senescence, promoted cell proliferation, improved DNA damage, enhanced insulin secretion and insulin synthesis of HG-induced pancreatic ß-cells through modulating the PERK/eIF2α signaling pathway.

2.
J Biochem Mol Toxicol ; 37(11): e23452, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37417536

RESUMO

Diabetes mellitus (DM), becomes a main public health issue worldwide due to the rapid increase in DM patient numbers. The dysfunction of endothelial progenitor cells (EPCs) in DM patients plays a critical role in endothelial repair and the progression of DM-related vascular complications. Loxenatide is an a glucagon-like peptide 1 receptor agonist, which is used to control glycemic in type 2 diabetes patients. However, the role of Loxenatide in EPCs remains to be investigated. EPCs were isolated, characterized, and treated with Loxenatide, high-glucose, or 3-TYP. quantitative real-time polymerase chain reaction, flow cytometry, western blot, and cell counting kit-8 assay were employed to validate the expression of gene and protein expressions and cell viability, respectively. Application of Seahorse XFp to measure oxygen consumption and mitochondrial membrane potential (MMP) were measured by Seahorse XFp and MMP assay. Loxenatide attenuated high-glucose-induced reactive oxygen species (ROS) production and mitochondrial-dependent apoptosis of EPCs in a concentration-dependent manner. The EPC mitochondrial respiration dysfunction induced by high glucose was also repressed by the loxenatide treatment. The protection effect of Loxenatide on EPCs against high-glucose was applied by activating the sirtuin 3 (SIRT3)/Foxo3 signaling pathway. We demonstrated the regulatory role of Loxenatide in mitochondrial dysfunction and apoptosis of EPCs. We elucidated that Loxenatide protects EPC from high-glucose-induced apoptosis via ROS-mediated mitochondrial pathway through the SIRT3/Foxo3 signing pathway. This may provide a new therapeutical target for the treatment of DM-related vascular complications.


Assuntos
Diabetes Mellitus Tipo 2 , Células Progenitoras Endoteliais , Sirtuína 3 , Humanos , Células Progenitoras Endoteliais/metabolismo , Sirtuína 3/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Transdução de Sinais , Apoptose , Glucose/farmacologia , Glucose/metabolismo , Mitocôndrias/metabolismo
3.
Bioorg Chem ; 138: 106663, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37329814

RESUMO

Glycogen synthase kinase 3ß (GSK-3ß) is a potential target for anti-Alzheimer's disease (AD) drug development. In this study, a series of novel thieno[3,2-c]pyrazol-3-amine derivatives was synthesized and evaluated as potential GSK-3ß inhibitors by structure-based drug design. The thieno[3,2-c]pyrazol-3-amine derivative 54 with a 4-methylpyrazole moiety which interacted with Arg141 by π-cation interaction was identified as a potent GSK-3ß inhibitor with an IC50 of 3.4 nM and an acceptable kinase selectivity profile. In the rat primary cortical neurons, compound 54 showed neuroprotective effects on Aß-induced neurotoxicity. Western blot analysis indicated that 54 inhibited GSK-3ß by up-regulating the expression of phosphorylated GSK-3ß at Ser9 and down-regulating the expression of phosphorylated GSK-3ß at Tyr216. Meanwhile, 54 decreased tau phosphorylation at Ser396 in a dose-dependent way. In astrocytes and microglia cells, 54 inhibited the expression of inducible nitric oxide synthase (iNOS), indicating that 54 showed an anti-neuroinflammatory effect. In the AlCl3-induced zebrafish AD model, 54 significantly ameliorated the AlCl3-induced dyskinesia, demonstrating its anti-AD activity in vivo.


Assuntos
Doença de Alzheimer , Proteínas tau , Ratos , Animais , Proteínas tau/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Peixe-Zebra/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Fosforilação
4.
Hepatobiliary Pancreat Dis Int ; 22(3): 263-269, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36435702

RESUMO

BACKGROUND: The effective treatment for hepatocellular carcinoma (HCC) depends on early diagnosis. Previously, the abnormal expression of Wnt3a as the key signaling molecule in the Wnt/ß-catenin pathway was found in HCC cells and could be released into the circulation. In this study, we used rat model of hepatocarcinogenesis to dynamically investigate the alteration of oncogenic Wnt3a and to explore its early monitor value for HCC. METHODS: Sprague-Dawley rats (SD) were fed with diet 2-fluorenylacetamide (2-FAA, 0.05%) for inducing hepatocarcinogenesis, and grouped based on liver morphological alteration by Hematoxylin & Eosin (H&E) staining; rats fed with normal chow were used as normal control (NC). Total RNA and protein were purified from rat livers. Differently expressed genes (DEGs) or Wnt3a mRNA, cellular distribution, and Wnt3a protein levels were analyzed by whole genome microarray with signal logarithm ratio (SLR log2cy5/cy3), immunohistochemistry, and enzyme-linked immunosorbent assay, respectively. RESULTS: Models of rat hepatocarcinogenesis were successfully established based on liver histopathological H&E staining. Rats were divided into the cell degeneration (rDeg), precancerosis (rPre-C) and HCC (rHCC) groups. Total numbers of the up- and down-regulated DEGs with SLR ≥ 8 were 55 and 48 in the rDeg group, 268 and 57 in the rPre-C group, and 312 and 201 in the rHCC group, respectively. Significantly altered genes were involved in cell proliferation, signal transduction, tumor metastasis, and apoptosis. Compared with the NC group, Wnt3a mRNA was increased by 4.6 folds (P < 0.001) in the rDeg group, 7.4 folds (P < 0.001) in the rPre-C group, and 10.4 folds (P < 0.001) in the rHCC group; the positive rates of liver Wnt3a were 66.7% (P = 0.001) in the rDeg group, 100% (P < 0.001) in the rPre-C group, and 100% (P < 0.001) in the rHCC group, respectively. Also, there were significant differences of liver Wnt3a (P < 0.001) or serum Wnt3a (P < 0.001) among different groups. CONCLUSIONS: Overexpression of Wnt3a was associated with rat hepatocarcinogenesis and it should be expected to be a promising monitoring biomarker for HCC occurrence at early stage.


Assuntos
Carcinogênese , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteína Wnt3A , Animais , Ratos , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Ratos Sprague-Dawley , RNA Mensageiro/metabolismo , Via de Sinalização Wnt , Proteína Wnt3A/análise
5.
Hum Brain Mapp ; 43(18): 5579-5592, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-35912517

RESUMO

Image-guided repetitive transcranial magnetic stimulation (rTMS) has shown clinical effectiveness in senior adults with co-occurring depression and cognitive impairment, yet the imaging markers for predicting the treatment response are less investigated. In this clinical trial, we examined the efficacy and sustainability of 10 Hz rTMS for the treatment of depression and cognitive impairment in major neurocognitive disorder (NCD) patients and tested the predictive values of imaging-informed radiomic features in response to rTMS treatment. Fifty-five major NCD patients with depression were randomly assigned to receive a 3-week rTMS treatment of either active 10 Hz rTMS (n = 27) or sham rTMS (n = 28). Left dorsolateral prefrontal cortex (DLPFC) was the predefined treatment target. Based on individual structural magnetic resonance imaging scans, surface-based analysis was conducted to quantitatively measure the baseline radiomic features of left DLPFC. Severity of depression, global cognition and the serum brain-derived neurotrophic factor (BDNF) level were evaluated at baseline, 3-, 6- and 12-week follow-ups. Logistic regression analysis revealed that advanced age, higher baseline cognition and randomized group were associated with the remission of depression. Increased cortical thickness and gyrification in left DLPFC were the significant predictors of clinical remission and cognitive enhancement. A 3-week course of 10 Hz rTMS is an effective adjuvant treatment for rapid ameliorating depressive symptoms and enhancing cognitive function. Pre-treatment radiomic features of the stimulation target can predict the response to rTMS treatment in major NCD. Cortical thickness and folding of treatment target may serve as imaging markers to detect the responders. ChiCTR-IOR-16008191, registered on March 30, 2016.


Assuntos
Disfunção Cognitiva , Transtorno Depressivo Maior , Adulto , Humanos , Estimulação Magnética Transcraniana/métodos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/terapia , Córtex Pré-Frontal/fisiologia , Resultado do Tratamento
6.
J Enzyme Inhib Med Chem ; 37(1): 1724-1736, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35698879

RESUMO

Glycogen synthase kinase 3ß (GSK-3ß) catalyses the hyperphosphorylation of tau protein in the Alzheimer's disease (AD) pathology. A series of novel thieno[3,2-c]pyrazol-3-amine derivatives were designed and synthesised and evaluated as potential GSK-3ß inhibitors by structure-guided drug rational design approach. The thieno[3,2-c]pyrazol-3-amine derivative 16b was identified as a potent GSK-3ß inhibitor with an IC50 of 3.1 nM in vitro and showed accepted kinase selectivity. In cell levels, 16b showed no toxicity on the viability of SH-SY5Y cells at the concentration up to 50 µM and targeted GSK-3ß with the increased phosphorylated GSK-3ß at Ser9. Western blot analysis indicated that 16b decreased the phosphorylated tau at Ser396 in a dose-dependent way. Moreover, 16b effectively increased expressions of ß-catenin as well as the GAP43, N-myc, and MAP-2, and promoted the differentiated neuronal neurite outgrowth. Therefore, the thieno[3,2-c]pyrazol-3-amine derivative 16b could serve as a promising GSK-3ß inhibitor for the treatment of AD.


Assuntos
Doença de Alzheimer , Aminas , Glicogênio Sintase Quinase 3 beta , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Aminas/síntese química , Aminas/farmacologia , Inibidores Enzimáticos/farmacologia , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Humanos , Fosforilação , Proteínas tau/metabolismo
7.
Mol Cancer ; 19(1): 53, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164750

RESUMO

BACKGROUND: The epigenetic regulation of immune response has been demonstrated in recent studies. Nonetheless, potential roles of RNA N6-methyladenosine (m6A) modification in tumor microenvironment (TME) cell infiltration remain unknown. METHODS: We comprehensively evaluated the m6A modification patterns of 1938 gastric cancer samples based on 21 m6A regulators, and systematically correlated these modification patterns with TME cell-infiltrating characteristics. The m6Ascore was constructed to quantify m6A modification patterns of individual tumors using principal component analysis algorithms. RESULTS: Three distinct m6A modification patterns were determined. The TME cell-infiltrating characteristics under these three patterns were highly consistent with the three immune phenotypes of tumors including immune-excluded, immune-inflamed and immune-desert phenotypes. We demonstrated the evaluation of m6A modification patterns within individual tumors could predict stages of tumor inflammation, subtypes, TME stromal activity, genetic variation, and patient prognosis. Low m6Ascore, characterized by increased mutation burden and activation of immunity, indicated an inflamed TME phenotype, with 69.4% 5-year survival. Activation of stroma and lack of effective immune infiltration were observed in the high m6Ascore subtype, indicating a non-inflamed and immune-exclusion TME phenotype, with poorer survival. Low m6Ascore was also linked to increased neoantigen load and enhanced response to anti-PD-1/L1 immunotherapy. Two immunotherapy cohorts confirmed patients with lower m6Ascore demonstrated significant therapeutic advantages and clinical benefits. CONCLUSIONS: This work revealed the m6A modification played a nonnegligible role in formation of TME diversity and complexity. Evaluating the m6A modification pattern of individual tumor will contribute to enhancing our cognition of TME infiltration characterization and guiding more effective immunotherapy strategies.


Assuntos
Adenosina/análogos & derivados , Linfócitos T CD8-Positivos/imunologia , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/imunologia , Microambiente Tumoral/imunologia , Adenosina/química , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Humanos , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Células Tumorais Cultivadas
8.
Bioorg Chem ; 103: 104109, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32768741

RESUMO

Histone deacetylases (HDACs) have been indicated important roles in neurodegenerative disorders including Alzheimer's disease (AD). Herein, a series of novel compounds that contain a memantine moiety were designed to target HDACs and N-methyl-d-aspartate receptor (NMDAR) which are related to the treatment of AD. Biological characterization established that compound 9d exhibited a balanced inhibitory activity on NMDAR and HDACs. This compound is relatively selective to HDAC6 with IC50 of 0.18 µM and also maintains comparable activity on NMDAR (Ki = 0.59 µM) as memantine. Functionally, treatment with 9d increased the level of AcTubulin in MV4-11 cells and rescued PC-12 cells from H2O2-induced cytotoxicity with EC50 of 0.94 µM. Studies in mice also demonstrated that compound 9d efficiently penetrates the blood brain barrier to reach the brain tissue. Collectively, the results strongly encourage further development of 9d as a potential therapeutic agent for AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Desenho de Fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Fármacos Neuroprotetores/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Doença de Alzheimer/metabolismo , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/farmacologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Células PC12 , Ratos , Receptores de N-Metil-D-Aspartato/metabolismo , Relação Estrutura-Atividade
9.
J Musculoskelet Neuronal Interact ; 20(1): 136-141, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32131378

RESUMO

OBJECTIVES: This study aims to investigate the changes in bone morphogenetic protein-2 (BMP-2) expression and mechanical properties in the healing process of rats with osteoporotic hindlimb fracture. METHODS: 120 rat models of osteoporotic hindlimb fracture were established and randomly divided into experimental group and control group. Quantitative real-time polymerase chain reaction (PCR) used to detect the BMP-2 expression in the rat's callus tissue on the fractured side. The mechanical properties of rat's hindlimb skeleton were examined using a universal material mechanics testing machine. RESULTS: The BMP-2 expression in the experimental group was higher than that in the control group (p<0.05). The linear correlation analysis showed that the BMP-2 was positively correlated with healing time (r=0.87, p<0.05). The mechanical properties were markedly improved at T2, T3 and T4, which peaked at T4 (p<0.05). However, the mechanical properties in the rats in the experimental group were notably superior to those in the control group at T2, T3, and T4 (p<0.05). CONCLUSIONS: The treatment with strontium ranelate can effectively improve the BMP-2 and bone mechanical properties of the rats with osteoporotic hindlimb fracture in the healing stage and accelerate the healing progress, which could be proved to be an efficacious means in treating osteoporotic fracture.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Proteína Morfogenética Óssea 2/biossíntese , Membro Posterior/metabolismo , Fraturas por Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/metabolismo , Tiofenos/uso terapêutico , Animais , Conservadores da Densidade Óssea/farmacologia , Proteína Morfogenética Óssea 2/genética , Feminino , Consolidação da Fratura/efeitos dos fármacos , Consolidação da Fratura/fisiologia , Expressão Gênica , Membro Posterior/efeitos dos fármacos , Membro Posterior/lesões , Ratos , Ratos Sprague-Dawley , Tiofenos/farmacologia , Resultado do Tratamento
10.
Acta Neurochir Suppl ; 127: 145-148, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407075

RESUMO

Delayed cerebral infarction (DCI) is related to unfavorable outcome after aneurysmal subarachnoid hemorrhage (SAH). There lacks a clear understanding how the DCI load affects cognitive function after SAH. We conducted a literature review on the clinical classification systems on brain hemorrhages and cerebral infarction and devised a Delayed Cerebral Infarction Load Scoring System (DCI Score). DCI Score significantly correlated with Symbol Digit Modalities Test (-0.334, p = 0.032), Color Trail Test (-0.310, p = 0.032), Hong Kong List Learning Test (-0.318, p = 0.036), Verbal Digit Span Forward (-0.382, p = 0.017), and Visual Digit Span Backward (-0.425, p = 0.012). In conclusion, higher DCI load impacted significantly on memory and executive function. DCI Score is a useful system for clinical quantification of DCI load and clinical research.


Assuntos
Infarto Cerebral , Hemorragia Subaracnóidea , Infarto Cerebral/diagnóstico , Hong Kong , Humanos , Testes Neuropsicológicos , Hemorragia Subaracnóidea/diagnóstico
11.
Neuroimage ; 199: 87-92, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31129301

RESUMO

Long-term married couples have been reported to share personality and behavioural similarities, but whether long-term marriage would shape the brain is hitherto unknown. In this study, 35 pairs of long-term married couples, who have married and living together at least 30 years, were recruited, and resting state functional magnetic resonance imaging was used to examine the neural correlates of long-term marriage between couples. Seven intrinsic connectivity networks were extracted using spatially constrained group independent component analysis, and the spatial similarity of each network as well as functional connectome similarity between couples were investigated respectively. The significant spatial similarities in the salience and frontoparietal networks as well as marginally significant connectome similarity were observed in long-term married couples. In addition, the marital duration showed a significantly positive correlation with the spatial similarity in the frontoparietal network and connectome similarity. The results provide objective evidence that long-term marriage would shape brain network organization, and the combination of initial personality traits and long-term common experience of the couples may be potential factors that account for similar brain network organizations between couples.


Assuntos
Córtex Cerebral/fisiologia , Conectoma , Rede Nervosa/fisiologia , Cônjuges , Idoso , Idoso de 80 Anos ou mais , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Casamento , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Fatores de Tempo
12.
Hum Brain Mapp ; 40(1): 340-351, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30240493

RESUMO

Age-related changes in functional brain network have been well documented. However, recent studies have suggested the nonstationary properties of the functional connectivity of the brain, and little is known about the changes of functional connectivity dynamics during aging. In this study, a two-step singular value decomposition was introduced to capture the dynamic patterns of the time-varying functional connectivity in different frequency intervals, and the whole-brain and regional brain diversity were quantified by using Shannon entropy. The relationships between age and functional connectivity dynamics were investigated in a relatively large sample cohort of cognitively healthy elderly (N = 188, ages 65-80). The results showed an age-related decreased diversity in the whole brain as well as in the right inferior frontal gyrus, right amygdala, right hippocampus, left parahippocampal, and left inferior parietal gyrus in the frequency interval of 0.06-0.12 Hz. In addition, the whole-brain diversity during resting state could also reflect the general mental flexibility. This study provided the first evidence of frequency-specific age effects on the functional connectivity dynamics in cognitively healthy elderly, and may shed new light on the dynamic functional connectivity analysis of aging and neurodegenerative diseases.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Conectoma/métodos , Rede Nervosa/fisiologia , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem
13.
Biochem Biophys Res Commun ; 516(3): 976-982, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31277940

RESUMO

Actin is a highly abundant cytoskeletal protein that is essential for all eukaryotic cells and participates in many structural and functional roles. It has long been noted that estrogen affects cellular morphology. However, recent studies observed that both estrogen and tamoxifen induce a remarkable cytoskeletal remodeling independent of ER. In addition to ER, G protein-coupled estrogen receptor 1 (GPER, also known as GPR30) also binds to estrogen with high affinity and mediates intracellular estrogenic signaling. Here, we show that activation of GPER by its specific agonist G-1 induces re-organization of F-actin cytoskeleton. We further demonstrate that GPER acts through PLCß-PKC and Rho/ROCK-LIMK-Cofilin pathway, which are upstream regulators of F-actin cytoskeleton assembly, thereby enhancing TAZ nuclear localization and activation. Furthermore, we find that LIMK1/2 is critical for GPER activation-induced breast cancer cell migration. Together, our results suggest that GPER mediates G-1-induced cytoskeleton assembly and GPER promotes breast cancer cell migration via PLCß-PKC and Rho/ROCK-LIMK-Cofilin pathway.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/genética , Regulação Neoplásica da Expressão Gênica , Quinases Lim/genética , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/genética , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/ultraestrutura , Fatores de Despolimerização de Actina/genética , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ciclopentanos/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos , Quinases Lim/antagonistas & inibidores , Quinases Lim/metabolismo , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Fosfolipase C beta/genética , Fosfolipase C beta/metabolismo , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Quinolinas/farmacologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Transativadores/genética , Transativadores/metabolismo , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
14.
Alzheimer Dis Assoc Disord ; 32(4): 309-313, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30024411

RESUMO

OBJECTIVE: This study aimed to test the hypothesis that the statistical Chinese brain template would be more effective to detect gray matter (GM) changes in patients with Alzheimer disease (AD) in Chinese populations. MATERIALS AND METHODS: In total, 50 patients with AD and 50 sex-matched and age-matched healthy controls were included in this study. Chinese2020, a typical statistical Chinese brain template, and MNI152, a typical Caucasian template were used for spatial normalization respectively. The GM volume alterations in patients with AD were examined by using voxel-based morphometry with education level and total intracranial volume as nuisance variables. The GM proportions of the identified brain areas with group difference were compared. RESULTS: By using Chinese2020 and MNI152, significant GM atrophies in patients with AD were commonly detected in the bilateral medial temporal lobe, lateral temporal lobe, inferior/medial frontal cortex, as well as left thalamus. However, higher GM percentages of detected regions were acquired when Chinese2020 was used rather than MNI152. Furthermore, stronger statistical powers in the detected clusters were observed using Chinese2020 than MNI152. In addition, the laterality index analysis showed the bilateral atrophies with no hemispheric laterality in the para/hippocampus when using population-specific brain atlas (ie, Chinese2020). CONCLUSIONS: These findings indicated that applying the population-specific brain atlas to neuroimaging studies may achieve higher accuracy in activation detection. This may have implications to the imaging study of neurodegenerative diseases.


Assuntos
Atrofia/patologia , Substância Cinzenta/patologia , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Idoso , Povo Asiático , China , Feminino , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Lobo Temporal/patologia
15.
J Stroke Cerebrovasc Dis ; 27(1): 44-52, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29107636

RESUMO

BACKGROUND: Computational fluid dynamics (CFD) allows noninvasive fractional flow (FF) computation in intracranial arterial stenosis. Removal of small artery branches is necessary in CFD simulation. The consequent effects on FF value needs to be judged. METHODS: An idealized vascular model was built with 70% focal luminal stenosis. A branch with one third or one half of the radius of the parent vessel was added at a distance of 5, 10, 15 and 20 mm to the lesion. With pressure and flow rate applied as inlet and outlet boundary conditions, CFD simulations were performed. Flow distribution at bifurcations followed Murray's law. By including or removing side branches, five patient-specific intracranial artery models were simulated. Transient simulation was performed on a patient-specific model, with a larger branch for validation. Branching effect was considered trivial if the FF difference between paired models (branches included or removed) was within 5%. RESULTS: Compared with the control model without a branch, in all idealized models the relative differences of FF was within 2%. In five pairs of cerebral arteries (branches included/removed), FFs were 0.876 and 0.877, 0.853 and 0.858, 0.874 and 0.869, 0.865 and 0.858, 0.952 and 0.948. The relative difference in each pair was less than 1%. In transient model, the relative difference of FF was 3.5%. CONCLUSION: The impact of removing side branches with radius less than 50% of the parent vessel on FF measurement accuracy is negligible in static CFD simulations, and minor in transient CFD simulation.


Assuntos
Artérias Cerebrais/fisiopatologia , Circulação Cerebrovascular , Doenças Arteriais Intracranianas/fisiopatologia , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Velocidade do Fluxo Sanguíneo , Angiografia Cerebral/métodos , Artérias Cerebrais/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Constrição Patológica , Humanos , Hidrodinâmica , Doenças Arteriais Intracranianas/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador , Fluxo Sanguíneo Regional
16.
Neuroimage ; 163: 368-378, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28712990

RESUMO

To study white matter changes in schizotypal personality disorder (SPD), we developed a new statistical analysis method based on supervoxels for diffusion tensor imaging. Twenty patients with SPD and eighteen healthy controls were recruited from a pool of 3000 first-year university undergraduates, and underwent MRI using a 3T scanner. Diffusion tensors were first normalized into ICBM-152 space followed by a supervoxel segmentation based on graph clustering to segment white matter tensors into diffusion homogeneous supervoxels. Fractional anisotropy (FA) values in supervoxels were compared between SPD and healthy controls using permutation test. Suprathreshold cluster size test was used to correct multiple comparison. At last, fibers with significant differences were extracted from supervoxel clusters with significance level P < 0.05. Results showed that FA values in genu of corpus callosum were significantly reduced (P = 0.012) in patients with SPD (FA = 0.565) compared with healthy controls (FA = 0.593). In summary, this study proposed a novel supervoxel segmentation method for diffusion tensor imaging using graph-based clustering, and extended permutation test and suprathreshold cluster size test to supervoxels for detection of white matter changes.


Assuntos
Algoritmos , Imagem de Tensor de Difusão/métodos , Interpretação de Imagem Assistida por Computador/métodos , Transtorno da Personalidade Esquizotípica/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino
17.
Radiology ; 285(3): 876-884, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28825891

RESUMO

Purpose To investigate the fat-water content of Achilles tendon xanthomas at baseline and after treatment and to compare this assessment with that of ultrasonography (US) and other magnetic resonance (MR) imaging-based parameters. Materials and Methods Forty-eight Achilles tendons with clinically apparent xanthomas in 24 patients with familial hypercholesterolemia (FH) (six men, 18 women; mean age ± standard deviation, 58 years ± 9) were compared with 20 Achilles tendons in 10 control subjects without FH (two men, eight women; mean age, 62 years ± 7). US imaging measurements (thickness, width, cross-sectional area, echogenicity) and 3.0-T MR imaging measurements (thickness, width, cross-sectional area, volume, and fat-water separation) of the Achilles tendons were obtained at baseline and in patients with FH at 3 and 6 months after treatment with probucol, a cholesterol-lowering agent. Nonparametric tests compared baseline data, whereas repeated-measures analyses assessed treatment change. Results At baseline, all US and MR imaging-based parameters were higher in xanthoma tendons compared with those in control tendons (all P < .05). The mean relative water content per unit volume was 71% higher (42.0% ± 6.7) in xanthoma tendons than in control tendons (24.5% 6 5.8; P < .001). After 6 months of cholesterol-lowering treatment, only MR imaging measurements of tendon volume (P = .007), relative fat (P = .041), and relative water content (P < .001) showed significant changes. As relative tendon fat content decreased with treatment, relative water content increased. Conclusion Most of the enlargement of Achilles tendon xanthomas is due to an increase in water content rather than fat. For depicting treatment change, relative tendon water content was the most sensitive parameter, followed by tendon volume and relative tendon fat content. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Tecido Adiposo/diagnóstico por imagem , Água Corporal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Xantomatose/diagnóstico por imagem , Xantomatose/tratamento farmacológico , Tendão do Calcâneo/efeitos dos fármacos , Tendão do Calcâneo/patologia , Tecido Adiposo/patologia , Idoso , Anticolesterolemiantes/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Probucol/uso terapêutico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Técnica de Subtração , Resultado do Tratamento , Xantomatose/patologia
18.
Exp Eye Res ; 160: 21-30, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28434813

RESUMO

Teleost fish continues to grow their eyes throughout life with the body size. In Astatotilapia burtoni, the fish retina increases by adding new retinal cells at the ciliary marginal zone (CMZ) and in the outer nuclear layer (ONL). Cell proliferation at both sites exhibits a daily rhythm in number of dividing cells. To understand how this diurnal rhythm of new cell production is controlled in retinal progenitor cells, we studied the transcription pattern of clock genes in retina, including clock1a, clock1b, bmal1a (brain and muscle ARNT-Like), and per1b (period1b). We found that these genes have a strong diurnal rhythmic transcription during light-dark cycles but not in constant darkness. An oscillation in pcna transcription was also observed during light-dark cycles, but again not in constant darkness. Our results also indicate an association between Clock proteins and the upstream region of pcna (proliferating cellular nuclear antigen) gene. A luciferase reporter assay conducted in an inducible clock knockdown cell line further demonstrated that the mutation on predicted E-Boxes in pcna promoter region significantly attenuated the transcriptional activation induced by Clock protein. These results suggested that the diurnal rhythmic expression of clock genes in A. burtoni retina could be light dependent and might contribute to the daily regulation of the proliferation of the retina progenitors through key components of cell cycle machinery, for instance, pcna.


Assuntos
Proteínas CLOCK/genética , Regulação da Expressão Gênica , Antígeno Nuclear de Célula em Proliferação/genética , RNA/genética , Retina/metabolismo , Animais , Western Blotting , Proteínas CLOCK/biossíntese , Divisão Celular , Linhagem Celular , Proliferação de Células , Ciclídeos , Ritmo Circadiano/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Luz , Camundongos , Modelos Animais , Fotoperíodo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Retina/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Transcrição Gênica
19.
J Magn Reson Imaging ; 46(3): 758-768, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28092409

RESUMO

PURPOSE: To develop a technique for the separation and quantification of brown adipose tissue (BAT) and white adipose tissue (WAT) using fat fraction and T2* intensity based on the Gaussian mixture model (GMM). MATERIALS AND METHODS: Chemical-shift water-fat and T2* images were acquired at the neck, supraclavicular, interscapular, and paravertebral regions in 24 volunteers (Obese: n = 12, female/male = 6/6, body mass index [BMI] = 31.3 ± 2.3 kg/m2 , age = 16.1 ± 0.6; Normal weight: n = 12, female/male = 6/6, BMI = 21.2 ± 2.4 kg/m2 , age = 12.9 ± 2.4) using a 3T scanner with the chemical-shift water-fat mDixon sequence. BAT and WAT were clustered based on the Gaussian mixture model using the expectation-maximization algorithm. Results and reproducibility were compared and assessed using independent t-tests and intraclass correlation coefficient. RESULTS: BAT in obese participants was predominately found at the supraclavicular region and in normal-weight participants it was more scattered and distributed in interscapular-supraclavicular, axillary, and spine regions. Absolute volume of BAT was higher in the obese group (Obese: 315.2 mL [±89.1], Normal weight: 248.5 mL [±86.4]), but BAT/WAT ratios were significantly higher (P = 0.029) in the normal group. T2* of BAT (P = 0.04) and volume of WAT (P < 0.001) were significantly lower in the normals. Within-group comparison between male and female indicated no significant differences were found in volume (P = 0.776 (normal), 0.501 [obese]), T2* (P = 0.908 [normal], 0.249 [obese]) and fat-fraction of BAT (P = 0.985 [normal], 0.108 [obese]). The intraclass correlation coefficient showed a good reproducibility in volume (BAT: 0.997, WAT: 0.948), T2* (BAT: 0.969, WAT: 0.983), and fat-fraction (BAT: 0.952, WAT: 0.517). CONCLUSION: BAT identified by this method was in agreement with other studies in terms of location, fat-fraction value, and T2* intensity. The proposed GMM-based segmentation could be a useful nonradiation imaging method for assessment of adipose tissue, in particular for serial follow-up of volume changes after drug or lifestyle interventions for obesity. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:758-768.


Assuntos
Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Branco/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Obesidade/diagnóstico por imagem , Adolescente , Criança , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
20.
J Vasc Interv Radiol ; 28(8): 1167-1176, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28506701

RESUMO

PURPOSE: It is hypothesized that intra-arterial administration of verapamil is a safe and effective way to reverse the flow in intraprostatic anastomoses to extraprostatic arteries without compromising treatment outcomes in prostatic artery embolization (PAE) for benign prostatic hypertrophy (BPH). MATERIALS AND METHODS: A prospective study of 62 prostate sides in 31 consecutive patients (median age, 66 y; range, 60-71 y) with symptomatic BPH was undertaken. Median prostate volume was 72.4 mL (range, 48.8-85.8 mL), median International Prostate Symptom Score was 21 (range, 15-23), and median urine peak flow rate was 4 mL/s (range, 2-6 mL/s). The arterial anastomoses were classified as types I-III according to vascular morphology. Treatment safety was assessed in terms of adverse events and complications, and treatment effectiveness was assessed in terms of success rate of angiographic flow reversal. RESULTS: The PAE procedure was successfully completed in all 31 patients (100%). Adverse events in both groups were transient and mild and did not necessitate prolonged hospitalization. There was no clinical evidence of any significant nontarget ischemic complication in either group. Intraprostatic anastomosis was diagnosed in 19 of 31 patients (61.3%) and 22 of 62 prostate sides (35.5%). Success rates of verapamil treatment were 88.9% overall (20 of 22) and 100% (19 of 19) in type II and III anastomoses. There was no difference between the treatment group and the control group in clinical, urologic, and imaging outcomes of PAE. CONCLUSIONS: Intra-arterial verapamil treatment was probably safe and effective in causing flow reversal in type II and III intraprostatic anastomoses and in preventing ischemic complications in PAE for BPH without compromising PAE outcomes.


Assuntos
Embolização Terapêutica/métodos , Próstata/irrigação sanguínea , Hiperplasia Prostática/terapia , Vasodilatadores/uso terapêutico , Verapamil/uso terapêutico , Idoso , Angiografia , Estudos de Casos e Controles , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Verapamil/administração & dosagem
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