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1.
Angiogenesis ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739303

RESUMO

Aging is a natural process associated with chronic inflammation in the development of vascular dysfunction. We hypothesized that chemokine C-C motif ligands 4 (CCL4) might play a vital role in aging-related vascular dysfunction. Circulating CCL4 was up-regulated in elderly subjects and in aged animals. CCL4 inhibition reduced generation of reactive oxygen species (ROS), attenuated inflammation, and restored cell functions in endothelial progenitor cells from elderly subjects and in aged human aortic endothelial cells. CCL4 promoted cell aging, with impaired cell functioning, by activating ROS production and inflammation. CCL4 knockout mice and therapeutic administration of anti-CCL4 neutralizing antibodies exhibited vascular and dermal anti-aging effects, with improved wound healing, via the down-regulation of inflammatory proteins and the activation of angiogenic proteins. Altogether, our findings suggested that CCL4 may contribute to aging-related vascular dysfunction via activating oxidative stress and endothelial inflammation. CCL4 may be a potential therapeutic target for vascular protections during aging.

2.
Hum Brain Mapp ; 45(11): e26777, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39046114

RESUMO

The development and refinement of functional brain circuits crucial to human cognition is a continuous process that spans from childhood to adulthood. Research increasingly focuses on mapping these evolving configurations, with the aim to identify markers for functional impairments and atypical development. Among human cognitive systems, nonsymbolic magnitude representations serve as a foundational building block for future success in mathematical learning and achievement for individuals. Using task-based frontoparietal (FPN) and salience network (SN) features during nonsymbolic magnitude processing alongside machine learning algorithms, we developed a framework to construct brain age prediction models for participants aged 7-30. Our study revealed differential developmental profiles in the synchronization within and between FPN and SN networks. Specifically, we observed a linear increase in FPN connectivity, concomitant with a decline in SN connectivity across the age span. A nonlinear U-shaped trajectory in the connectivity between the FPN and SN was discerned, revealing reduced FPN-SN synchronization among adolescents compared to both pediatric and adult cohorts. Leveraging the Gradient Boosting machine learning algorithm and nested fivefold stratified cross-validation with independent training datasets, we demonstrated that functional connectivity measures of the FPN and SN nodes predict chronological age, with a correlation coefficient of .727 and a mean absolute error of 2.944 between actual and predicted ages. Notably, connectivity within the FPN emerged as the most contributing feature for age prediction. Critically, a more matured brain age estimate is associated with better arithmetic performance. Our findings shed light on the intricate developmental changes occurring in the neural networks supporting magnitude representations. We emphasize brain age estimation as a potent tool for understanding cognitive development and its relationship to mathematical abilities across the critical developmental period of youth. PRACTITIONER POINTS: This study investigated the prolonged changes in the brain's architecture across childhood, adolescence, and adulthood, with a focus on task-state frontoparietal and salience networks. Distinct developmental pathways were identified: frontoparietal synchronization strengthens consistently throughout development, while salience network connectivity diminishes with age. Furthermore, adolescents show a unique dip in connectivity between these networks. Leveraging advanced machine learning methods, we accurately predicted individuals' ages based on these brain circuits, with a more mature estimated brain age correlating with better math skills.


Assuntos
Lobo Frontal , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Rede Nervosa , Lobo Parietal , Humanos , Adolescente , Criança , Adulto Jovem , Masculino , Feminino , Adulto , Lobo Parietal/fisiologia , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/crescimento & desenvolvimento , Lobo Frontal/fisiologia , Lobo Frontal/crescimento & desenvolvimento , Lobo Frontal/diagnóstico por imagem , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Rede Nervosa/crescimento & desenvolvimento , Conceitos Matemáticos , Conectoma
3.
Eur J Neurosci ; 58(5): 3299-3314, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37468321

RESUMO

Numerous empirical studies have reported that males and females perform equally well in mathematical achievement. However, still to date, very limited is understood about the brain response profiles that are particularly characteristic of males and females when solving mathematical problems. The present study aimed to tackle this issue by manipulating arithmetic problem size to investigate functional significance using functional magnetic resonance imaging (fMRI) in young adults. Participants were instructed to complete two runs of simple calculation tasks with either large or small problem sizes. Behavioural results suggested that the performance did not differ between females and males. Neuroimaging data revealed that sex/gender-related patterns of problem size effect were found in the brain regions that are conventionally associated with arithmetic, including the left middle frontal gyrus (MFG), left intraparietal sulcus (IPS) and insula. Specifically, females demonstrated substantial brain responses of problem size effect in these regions, whereas males showed marginal effects. Moreover, the machine learning method implemented over the brain signal levels within these regions demonstrated that sex/gender is discriminable. These results showed sex/gender effects in the activating patterns varying as a function of the distinct math problem size, even in a simple calculation task. Accordingly, our findings suggested that females and males use two complementary brain resources to achieve equally successful performance levels and highlight the pivotal role of neuroimaging facilities in uncovering neural mechanisms that may not be behaviourally salient.


Assuntos
Mapeamento Encefálico , Resolução de Problemas , Masculino , Adulto Jovem , Humanos , Feminino , Resolução de Problemas/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Lobo Parietal/fisiologia , Imageamento por Ressonância Magnética/métodos
4.
Cardiovasc Diabetol ; 22(1): 172, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420254

RESUMO

BACKGROUND: Higher chemokine C-X-C motif ligand 5 (CXCL5) level was observed in type 2 diabetes mellitus (DM) patients; however, its role in diabetic vasculopathy was not clarified. This study aimed to explore the impacts and mechanistic insights of CXCL5 in neovasculogenesis and wound healing in DM. METHODS: Endothelial progenitor cells (EPCs) and human aortic endothelial cells (HAECs) were used in vitro. Streptozotocin-induced diabetic mice and Leprdb/JNarl mice were used as type 1 and type 2 DM models. Moreover, CXCL5 knockout mice were used to generate diabetic mice. Hindlimb ischemia surgery, aortic ring assays, matrigel plug assay, and wound healing assay were conducted. RESULTS: CXCL5 concentrations were increased in plasma and EPCs culture medium from type 2 DM patients. CXCL5 neutralizing antibody upregulated vascular endothelial growth factor (VEGF)/stromal cell-derived factor-1 (SDF-1) and promoted cell function in EPCs from type 2 DM patients and high glucose-treated EPCs from non-DM subjects as well as HAECs. CXCL5 directly up-regulated interleukin (IL)-1ß/IL-6/tumor necrosis factor-α and down-regulated VEGF/SDF-1 via ERK/p65 activation through chemokine C-X-C motif receptor 2 (CXCR2). CXCL5 neutralizing antibody recovered the blood flow after hindlimb ischemia, increased circulating EPC number, and enhanced VEGF and SDF-1 expression in ischemic muscle. CXCL5 suppression promoted neovascularization and wound healing in different diabetic animal models. The above observation could also be seen in streptozotocin-induced CXCL5 knockout diabetic mice. CONCLUSIONS: CXCL5 suppression could improve neovascularization and wound healing through CXCR2 in DM. CXCL5 may be regarded as a potential therapeutic target for vascular complications of DM.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Células Progenitoras Endoteliais , Humanos , Camundongos , Animais , Diabetes Mellitus Tipo 2/metabolismo , Fator A de Crescimento do Endotélio Vascular , Diabetes Mellitus Experimental/metabolismo , Estreptozocina/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Células Progenitoras Endoteliais/metabolismo , Quimiocina CXCL12/metabolismo , Camundongos Knockout , Cicatrização , Isquemia , Neovascularização Fisiológica/fisiologia , Quimiocina CXCL5/genética , Quimiocina CXCL5/metabolismo
5.
Cardiovasc Diabetol ; 21(1): 185, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109744

RESUMO

Chemokines are key components in the pathology of chronic diseases. Chemokine CC motif ligand 7 (CCL7) is believed to be associated with cardiovascular disease, diabetes mellitus, and kidney disease. CCL7 may play a role in inflammatory events by attracting macrophages and monocytes to further amplify inflammatory processes and contribute to disease progression. However, CCL7-specific pathological signaling pathways need to be further confirmed in these chronic diseases. Given the multiple redundancy system among chemokines and their receptors, further experimental and clinical studies are needed to clarify whether direct CCL7 inhibition mechanisms could be a promising therapeutic approach to attenuating the development of cardiovascular disease, diabetes mellitus, and kidney disease.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Nefropatias , Quimiocina CCL7/metabolismo , Quimiocinas/metabolismo , Humanos , Ligantes
6.
Ecotoxicol Environ Saf ; 244: 114062, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36108433

RESUMO

Bioenzymatic degradation of aflatoxin B1 (AFB1) is a safe, efficient and environmentally friendly detoxification technology. In this work, AFB1 was successfully degraded by recombinant laccase (fmb-rL103) in the absence of a mediator. The laccase gene was cloned from Bacillus vallismortis fmb-103, and was expressed in heterologous host Escherichia coli after codon optimization. The extracellular production of fmb-rL103 could be induced by adding methanol (6 %, v/v), and the maximum yield was 1545.6 U/L. In the 10 L bioreactor, the extracellular yield increased to 50,950.6 U/L after 20 h of induction, accounting for three quarters of the total yield. The mechanism of methanol-induced extracellular secretion was further studied by measuring acetate content, lac103 gene expression and cell membrane permeability. Furthermore, we explored the biochemical properties of fmb-rL103 and its degradation conditions on AFB1. The degradation efficiency increased constantly with increase in incubation pH and temperature, and exceeded 60 % at pH 7.0 and 37 °C. This work provides new insight into developing the large-scale production of laccase and its application to degrade AFB1.


Assuntos
Aflatoxina B1 , Lacase , Aflatoxina B1/química , Escherichia coli/genética , Escherichia coli/metabolismo , Lacase/metabolismo , Metanol/metabolismo , Temperatura
7.
Opt Express ; 29(7): 10285-10306, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33820168

RESUMO

This paper presents a passive autofocus algorithm applicable to interferometric microscopes. The proposed algorithm uses the number of slope variations in an image mask to locate the focal plane (based on focus-inflection points) and identify the two neighboring planes at which fringes respectively appear and disappear. In experiments involving a Mirau objective lens, the proposed algorithm matched the autofocusing performance of conventional algorithms, and significantly outperformed detection schemes based on zero-order interference fringe in dealing with all kinds of surface blemish, regardless of severity. In experiments, the proposed algorithm also proved highly effective in cases without fringes.

8.
Pharmacol Res ; 151: 104509, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678640

RESUMO

Oxidative stress is related to the progression of renal diseases and modulation of oxidative stress can lead to a reduction in vascular events in patients with chronic renal insufficiency (CRI). Indoxyl sulfate (IS) and xanthine oxidase (XO) are related to impaired neovasculogenesis in CRI. Hydralazine is suggested for blood pressure control in CRI. This study aimed to investigate whether hydralazine could improve ischemia-induced neovasculogenesis in CRI animals by reducing reactive oxygen species (ROS) levels. Mice underwent subtotal nephrectomy or sham surgery. Nitrendipine, probenecid, and allopurinol were used to reduce blood pressure, uric acid (UA), and XO activity levels, respectively, for comparison. Blood pressure, XO activity and UA levels that were increased after subtotal nephrectomy were reduced by hydralazine treatment. Allopurinol decreased blood XO activity and UA levels. Only hydralazine and allopurinol increased the number of circulating endothelial progenitor cells (EPCs) and improved neovasculogenesis in CRI mice. IS activated XO mRNA and ROS and inhibited the functions of EPCs and endothelial cells, which could be reversed by hydralazine. However, no additional beneficial effects were observed when XO was inhibited with both hydralazine and siRNA. In conclusion, hydralazine, as a potential XO inhibitor, not only reduced blood pressure and UA levels but also increased the number of circulating EPCs and improved neovasculogenesis in CRI animals. Hydralazine directly inhibited IS-induced ROS and XO activation in EPCs and endothelial cells, and restored their functions in vitro. Future studies should evaluate whether hydralazine could provide additional vascular protection in patients with CRI.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Hidralazina/uso terapêutico , Isquemia/complicações , Neovascularização Fisiológica/efeitos dos fármacos , Insuficiência Renal Crônica/complicações , Xantina Oxidase/antagonistas & inibidores , Alopurinol/uso terapêutico , Animais , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Células Cultivadas , Humanos , Isquemia/tratamento farmacológico , Isquemia/fisiopatologia , Masculino , Camundongos , Espécies Reativas de Oxigênio/análise , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/fisiopatologia
9.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365893

RESUMO

Kidney function decline is one of the complications of diabetes mellitus and may be indicated as diabetic nephropathy (DN). DN is a chronic inflammatory disease featuring proteinuria and a decreasing glomerular filtration rate. Despite several therapeutic options being currently available, DN is still the major cause of end-stage renal disease. Accordingly, widespread innovation is needed to improve outcomes in patients with DN. Chemokines and their receptors are critically involved in the inflammatory progression in the development of DN. Although recent studies have shown multiple pathways related to the chemokine system, the specific and direct effects of chemokines and their receptors remain unclear. In this review, we provide an overview of the potential role and mechanism of chemokine systems in DN proposed in recent years. Chemokine system-related mechanisms may provide potential therapeutic targets in DN.


Assuntos
Quimiocinas/metabolismo , Diabetes Mellitus/metabolismo , Nefropatias Diabéticas/imunologia , Nefropatias Diabéticas/metabolismo , Receptores de Quimiocinas/metabolismo , Animais , Diabetes Mellitus/imunologia , Humanos , Inflamação/imunologia , Inflamação/metabolismo
10.
Int J Mol Sci ; 21(23)2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33287461

RESUMO

Background-Elevated circulating fatty-acid-binding protein 4 (FABP4) levels may be linked with cardiovascular events. This study aimed to investigate the mechanistic role of FABP4 in atherosclerosis. Methods-We recruited 22 patients with angiographically proven coronary artery disease (CAD) and 40 control subjects. Mononuclear cells (MNCs) and human coronary endothelial cells (HCAECs) were used for in vitro study. Results-Patients with CAD were predominantly male with an enhanced prevalence of hypertension, diabetes, and smoking history. FABP4 concentrations were up-regulated in culture supernatants of MNCs from CAD patients, which were positively correlated with the patients' age, waist-hip ratio, body mass index, serum creatinine, type 2 diabetes, and the presence of hypertension. The adhesiveness of HCAECs to monocytic cells can be activated by FABP4, which was reversed by an FABP4 antibody. FABP4 blockade attenuated the oxidized low-density lipoprotein (oxLDL)-induced expression of ICAM-1, VCAM-1, and P-selectin. FABP4 impaired the tube formation and migration via the ERK/JNK/STAT-1 signaling pathway. FABP4 suppressed phosphorylation of eNOS and expression of SDF-1 protein, both of which can be reversed by treatment with VEGF. Blockade of FABP4 also improved the oxLDL-impaired cell function. Conclusion-We discovered a novel pathogenic role of FABP4 in MNC activation and endothelial dysfunction in atherosclerosis. FABP4 may be a therapeutic target for modulating atherosclerosis.


Assuntos
Aterosclerose/etiologia , Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Idoso , Aterosclerose/patologia , Antígenos CD18/metabolismo , Adesão Celular , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Suscetibilidade a Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Cadeias alfa de Integrinas/metabolismo , Lipoproteínas LDL/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais
11.
Int J Mol Sci ; 21(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911750

RESUMO

Atherosclerosis is an arterial inflammatory disease. The circulating level of the C-C chemokine ligand (CCL4) is increased in atherosclerotic patients. This study aimed to investigate whether CCL4 inhibition could retard the progression of atherosclerosis. In ApoE knockout mice, CCL4 antibody treatment reduced circulating interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α levels and improved lipid profiles accompanied with upregulation of the liver X receptor. CCL4 inhibition reduced the atheroma areas and modified the progression of atheroma plaques, which consisted of a thicker fibrous cap with a reduced macrophage content and lower matrix metalloproteinase-2 and -9 expressions, suggesting the stabilization of atheroma plaques. Human coronary endothelial cells (HCAECs) and macrophages were stimulated with TNF-α or oxidized LDL (ox-LDL). The induced expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) were attenuated by the CCL4 antibody or CCL4 si-RNA. CCL4 inhibition reduced the adhesiveness of HCAECs, which is an early sign of atherogenesis. CCL4 blockade reduced the activity of metalloproteinase-2 and -9 and the production of TNF-α and IL-6 in stimulated macrophages. The effects of CCL4 inhibition on down-regulating adhesion and inflammation proteins were obtained through the nuclear factor kappa B (NFκB) signaling pathway. The direct inhibition of CCL4 stabilized atheroma and reduced endothelial and macrophage activation. CCL4 may be a novel therapeutic target for modulating atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Quimiocina CCL4/antagonistas & inibidores , Adesividade , Animais , Aterosclerose/fisiopatologia , Adesão Celular/fisiologia , Quimiocina CCL4/metabolismo , Células Endoteliais/metabolismo , Humanos , Inflamação/patologia , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , Ligantes , Lipoproteínas LDL/metabolismo , Receptores X do Fígado/metabolismo , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , NF-kappa B/metabolismo , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
12.
Angiogenesis ; 22(1): 53-65, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29987448

RESUMO

Systemic inflammation might contribute to the impairment of neovasculogenesis and endothelial progenitor cell (EPC) function in clinical diabetes mellitus (DM). Macrophage inflammatory protein-1ß (MIP-1ß) is an inflammatory chemokine that may be up-regulated in clinical DM. Its role in diabetic vasculopathy was not clarified. This study aimed to investigate the role of MIP-1ß in human EPCs and in neovasculogenesis in different diabetic animal models with hindlimb ischemia. EPCs chamber assay and in vitro tube formation assay were used to estimate the degree of EPC migration and tube formation abilities. Leprdb/JNarl mice, C57BL/6 mice fed a high-fat diet, and streptozotocin-induced diabetic mice were used as different diabetic animal models. Laser Doppler imaging and flow cytometry were used to evaluate the degree of neovasculogenesis and the circulating levels of EPCs, respectively. MIP-1ß impaired human EPC function for angiogenesis in vitro. Plasma MIP-1ß levels were up-regulated in type 2 DM patients. MIP-1ß inhibition enhanced the function and the C-X-C chemokine receptor type 4 expression of EPCs from type 2 diabetic patients, and improved EPC homing for ischemia-induced neovasculogenesis in different types of diabetic animals. MIP-1ß directly impaired human EPC function. Inhibition of MIP-1ß improved in vitro EPC function, and enhanced in vivo EPC homing and ischemia-induced neovasculogenesis, suggesting the critical role of MIP-1ß for vasculopathy in the presence of DM.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Quimiocina CCL4/metabolismo , Diabetes Mellitus Experimental/metabolismo , Células Progenitoras Endoteliais/metabolismo , Isquemia/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Quimiocina CCL4/genética , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Células Progenitoras Endoteliais/patologia , Humanos , Isquemia/patologia , Masculino , Camundongos , Camundongos Transgênicos , Neovascularização Patológica/patologia
13.
Hum Brain Mapp ; 40(6): 1927-1941, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30565340

RESUMO

Mathematical word problems are ubiquitous and standard for teaching and evaluating generalization of mathematical knowledge for real-world contexts. It is therefore concerning that the neural mechanisms of word problem solving are not well understood, as these insights represent strong potential for improving education and remediating deficits in this domain. Here, we investigate neural response to word problems via functional magnetic resonance imaging (fMRI). Healthy adults performed sentence judgment tasks on word problems that either contained one-step mathematical operations, or nonarithmetic judgments on parallel narratives without any numerical information. Behavioral results suggested that the composite efficiency measurement of combining accuracy and RT did not differ between the two problem types. Arithmetic sentence judgments elicited greater activation in the fronto-insular-parietal network including intraparietal sulcus (IPS), dorsolateral prefrontal cortex (PFC), and anterior insula (AI) than narrative sentence judgment. Narrative sentence judgments, conversely, resulted in greater activation predominantly in the left ventral PFC, angular gyrus and perisylvian cortex compared with reading arithmetic sentences. Moreover, task-dependent functional connectivity analyses showed the AI circuits were more strongly coupled with IPS during arithmetic sentence judgments than nonarithmetic sentences. Finally, activations in the IPS during arithmetic were highly correlated with out-of-scanner performance on a distinct set of problems with the same characteristics. These results show arithmetic word problem performance differences may rely more heavily on fronto-insular-parietal circuits for mathematical model building than narrative text comprehension of similar difficulty. More broadly, our study suggests that quantitative measurements of brain mechanisms can provide pivotal role for uncovering crucial arithmetic skills.


Assuntos
Córtex Cerebral/fisiologia , Matemática , Rede Nervosa/fisiologia , Resolução de Problemas/fisiologia , Adulto , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Individualidade , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Tempo de Reação/fisiologia , Adulto Jovem
14.
Neuroimage ; 167: 162-177, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29162521

RESUMO

The neural substrates of children's reading and arithmetic skills have long been of great interest to cognitive neuroscientists. However, most previous studies have focused on the contrast between these skills as specific domains. Here, we investigate the potentially shared processes across these domains by focusing on how the neural circuits associated with cognitive control influence reading and arithmetic proficiency in 8-to-10-year-old children. Using a task-free resting state approach, we correlated the intrinsic functional connectivity of the right anterior insula (rAI) network with performance on assessments of Chinese character recognition, reading comprehension, subtraction, and multiplication performance. A common rAI network strengthened for reading and arithmetic skill, including the right middle temporal gyrus (MTG) and superior temporal gyrus (STG) in the lateral temporal cortex, as well as the inferior frontal gyrus (IFG). In addition, performance measures evidenced rAI network specializations. Single character recognition was uniquely associated with connectivity to the right superior parietal lobule (SPL). Reading comprehension only, rather than character recognition, was associated with connectivity to the right IFG, MTG and angular gyrus (AG). Furthermore, subtraction was associated with connectivity to premotor cortex whereas multiplication was associated with the supramarginal gyrus. Only reading comprehension and multiplication were associated with hyper connectivity within local rAI network. These results indicate that during a critical period for children's acquisition of reading and arithmetic, these skills are supported by both intra-network synchronization and inter-network connectivity of rAI circuits. Domain-general intrinsic insular connectivity at rest contained also, functional components that segregated into different sets of skill-related networks. The embedded components of cognitive control may be essential to understanding the interplay of multiple functional circuits necessary to more fully characterize cognitive skill acquisition.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Desenvolvimento Infantil/fisiologia , Compreensão/fisiologia , Função Executiva/fisiologia , Conceitos Matemáticos , Rede Nervosa/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Leitura , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
16.
Neuroimage ; 126: 184-95, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26655682

RESUMO

Human cognitive problem solving skills undergo complex experience-dependent changes from childhood to adulthood, yet most neurodevelopmental research has focused on linear changes with age. Here we challenge this limited view, and investigate spatially heterogeneous and nonlinear neurodevelopmental profiles between childhood, adolescence, and young adulthood, focusing on three cytoarchitectonically distinct posterior parietal cortex (PPC) regions implicated in numerical problem solving: intraparietal sulcus (IPS), angular gyrus (AG), and supramarginal gyrus (SMG). Adolescents demonstrated better behavioral performance relative to children, but their performance was equivalent to that of adults. However, all three groups differed significantly in their profile of activation and connectivity across the PPC subdivisions. Activation in bilateral ventral IPS subdivision IPS-hIP1, along with adjoining anterior AG subdivision, AG-PGa, and the posterior SMG subdivision, SMG-PFm, increased linearly with age, whereas the posterior AG subdivision, AG-PGp, was equally deactivated in all three groups. In contrast, the left anterior SMG subdivision, SMG-PF, showed an inverted U-shaped profile across age groups such that adolescents exhibited greater activation than both children and young adults. Critically, greater SMG-PF activation was correlated with task performance only in adolescents. Furthermore, adolescents showed greater task-related functional connectivity of the SMG-PF with ventro-temporal, anterior temporal and prefrontal cortices, relative to both children and adults. These results suggest that nonlinear up-regulation of SMG-PF and its interconnected functional circuits facilitate adult-level performance in adolescents. Our study provides novel insights into heterogeneous age-related maturation of the PPC underlying cognitive skill acquisition, and further demonstrates how anatomically precise analysis of both linear and nonlinear neurofunctional changes with age is necessary for more fully characterizing cognitive development.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Desenvolvimento Infantil/fisiologia , Conectoma/métodos , Lobo Parietal/crescimento & desenvolvimento , Lobo Parietal/fisiologia , Resolução de Problemas/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
17.
Cardiovasc Diabetol ; 15(1): 117, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27553774

RESUMO

Chemokines are critical components in pathology. The roles of chemokine CC motif ligand 4 (CCL4) and its receptor are associated with diabetes mellitus (DM) and atherosclerosis cardiovascular diseases. However, due to the complexity of these diseases, the specific effects of CCL4 remain unclear, although recent reports have suggested that multiple pathways are related to CCL4. In this review, we provide an overview of the role and potential mechanisms of CCL4 and one of its major receptors, fifth CC chemokine receptor (CCR5), in DM and cardiovascular diseases. CCL4-related mechanisms, including CCL4 and CCR5, might provide potential therapeutic targets in DM and/or atherosclerosis cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/metabolismo , Quimiocina CCL4/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Transdução de Sinais , Animais , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/imunologia , Quimiocina CCL4/imunologia , Complicações do Diabetes/imunologia , Complicações do Diabetes/metabolismo , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/imunologia , Humanos , Hipoglicemiantes/uso terapêutico , Ligantes , Receptores CCR5/imunologia , Receptores CCR5/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Eur J Clin Invest ; 46(6): 544-54, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27062013

RESUMO

BACKGROUND: Endothelial progenitor cell (EPC) functions are impaired in the presence of diabetes mellitus. Aliskiren is a direct renin inhibitor, which is expected to modify proangiogenic cells. This study aimed to investigate whether and how aliskiren could improve the function of EPCs from patients with type II diabetes (T2DM). MATERIALS AND METHODS: Endothelial progenitor cells fibronectin adhesion assay, chamber assay and in vitro tube formation assay were used to estimate the degree of EPC adhesion, migration and tube formation abilities. EPC protein and mRNA expressions were evaluated by Western blot and quantitative RT-PCR, respectively. EPC vascular endothelial growth factor (VEGF) and (pro)renin receptor ((P)RR) expression was knocked down by VEGF and (P)RR siRNA. RESULTS: Aliskiren (0·1 or 10 µM) dose-dependently improved functions and increased both VEGF and stromal cell-derived factor-1α (SDF-1α) expression of EPCs from patients with T2DM or EPCs from healthy volunteers and treated with high glucose. Transfection with VEGF siRNA significantly reduced the aliskiren-induced SDF-1α expression. Furthermore, (P)RR siRNA transfection impaired the aliskiren-induced VEGF and SDF-1 expression. CONCLUSIONS: The results show that aliskiren improved EPC function from patients with T2DM in a dose-dependent manner probably via the (P)RR and VEGF/SDF-1α-related mechanisms.


Assuntos
Amidas/farmacologia , Anti-Hipertensivos/farmacologia , Diabetes Mellitus Tipo 2 , Células Progenitoras Endoteliais/efeitos dos fármacos , Fumaratos/farmacologia , RNA Mensageiro/efeitos dos fármacos , Western Blotting , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL12/efeitos dos fármacos , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Células Progenitoras Endoteliais/metabolismo , Humanos , Hidralazina/farmacologia , Imidazóis/farmacologia , Técnicas In Vitro , Óxido Nítrico Sintase Tipo III/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tetrazóis/farmacologia , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
NMR Biomed ; 28(6): 642-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25880892

RESUMO

The forward volumetric transfer constant (K(trans)), a physiological parameter extracted from dynamic contrast-enhanced (DCE) MRI, is weighted by vessel permeability and tissue blood flow. The permeability × surface area product per unit mass of tissue (PS) in brain tumors was estimated in this study by combining the blood flow obtained through pseudo-continuous arterial spin labeling (PCASL) and K(trans) obtained through DCE MRI. An analytical analysis and a numerical simulation were conducted to understand how errors in the flow and K(trans) estimates would propagate to the resulting PS. Fourteen pediatric patients with brain tumors were scanned on a clinical 3-T MRI scanner. PCASL perfusion imaging was performed using a three-dimensional (3D) fast-spin-echo readout module to determine blood flow. DCE imaging was performed using a 3D spoiled gradient-echo sequence, and the K(trans) map was obtained with the extended Tofts model. The numerical analysis demonstrated that the uncertainty of PS was predominantly dependent on that of K(trans) and was relatively insensitive to the flow. The average PS values of the whole tumors ranged from 0.006 to 0.217 min(-1), with a mean of 0.050 min(-1) among the patients. The mean K(trans) value was 18% lower than the PS value, with a maximum discrepancy of 25%. When the parametric maps were compared on a voxel-by-voxel basis, the discrepancies between PS and K(trans) appeared to be heterogeneous within the tumors. The PS values could be more than two-fold higher than the K(trans) values for voxels with high K(trans) levels. This study proposes a method that is easy to implement in clinical practice and has the potential to improve the quantification of the microvascular properties of brain tumors.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Permeabilidade Capilar , Artérias Cerebrais/fisiopatologia , Circulação Cerebrovascular , Gadolínio DTPA/farmacocinética , Angiografia por Ressonância Magnética/métodos , Adolescente , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Determinação do Volume Sanguíneo , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Artérias Cerebrais/patologia , Criança , Pré-Escolar , Meios de Contraste/farmacocinética , Estudos de Viabilidade , Feminino , Humanos , Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Marcadores de Spin
20.
Psychogeriatrics ; 15(2): 109-115, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25521171

RESUMO

OBJECTIVE: Metabolic syndrome and depression are both thought to be associated with cognitive impairment in the elderly. Metabolic syndrome is also correlated with depression. We examined their possible pathways in a population-based sample. METHODS: We recruited 300 older community participants from Southern Taiwan. Demographics, medical history, severity of depressive symptoms, cognitive function, apolipoprotein genotyping, and lipid profile were collected. The presence of metabolic syndrome was confirmed with the Third Report of the National Cholesterol Education Program's Adult Treatment Panel. Possible relationships between metabolic syndrome, depressive symptoms, and cognitive dysfunction were explored using logistic regression and structured equation modelling. RESULTS: When gender, age, education, marital status, and apolipoprotein genotype were adjusted for logistic regression, metabolic syndrome and depressive symptoms were independent and significant predictors of cognitive dysfunction for community-dwelling elderly. In structural equation modelling, metabolic syndrome and depressive symptoms were correlated to each other, and both contributed to the presence of cognitive dysfunction. CONCLUSIONS: Depressive symptoms and metabolic syndrome are independently associated with cognitive impairment among community-dwelling elderly.

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