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1.
Neurochem Res ; 49(6): 1592-1602, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38305960

RESUMO

In the present study, sulfated polysaccharides were obtained by digestion of Sargassum horneri and preparation with enzyme-assisted extraction using three food-grade enzymes, and their anti- Alzheimer's activities were investigated. The results demonstrated that the crude sulfated polysaccharides extracted using AMGSP, CSP and VSP dose-dependently (25-100 µg·mL- 1) raised the spontaneous alternating manner (%) in the Y maze experiment of mice and reduced the escape latency time in Morris maze test. AMGSP, CSP and VSP also exhibited good anti-AChE and moderate anti-BuChE activities. CSP displayed the best inhibitory efficacy against AChE. with IC50 values of 9.77 µM. And, CSP also exhibited good inhibitory selectivity of AChE over BuChE. Next, CSP of the best active crude extract was separated by the preparation type high performance liquid phase to obtain the sulphated fucooligosaccharide section: SFcup (→3-α-L-fucp(2-SO3-)-1→4-α-L-fucp(2,3-SO3-)-1→section), SFcup showed a best inhibitory efficacy against AChE with IC50 values of 4.03 µM. The kinetic research showed that SFcup inhibited AChE through dual binding sites. Moreover, the molecular docking of SFcup at the AChE active site was in accordance with the acquired pharmacological results.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Inibidores da Colinesterase , Simulação de Acoplamento Molecular , Oligossacarídeos , Sargassum , Sargassum/química , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/química , Inibidores da Colinesterase/uso terapêutico , Camundongos , Acetilcolinesterase/metabolismo , Oligossacarídeos/farmacologia , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Masculino , Sulfatos/química , Sulfatos/farmacologia , Butirilcolinesterase/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Relação Dose-Resposta a Droga
2.
Mov Disord ; 38(12): 2217-2229, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37752895

RESUMO

BACKGROUND: Rare mutations in NADH:ubiquinone oxidoreductase complex assembly factor 5 (NDUFAF5) are linked to Leigh syndrome. OBJECTIVE: We aimed to describe clinical characteristics and functional findings in a patient cohort with NDUFAF5 mutations. METHODS: Patients with biallelic NDUFAF5 mutations were recruited from multi-centers in Taiwan. Clinical, laboratory, radiological, and follow-up features were recorded and mitochondrial assays were performed in patients' skin fibroblasts. RESULTS: Nine patients from seven unrelated pedigrees were enrolled, eight homozygous for c.836 T > G (p.Met279Arg) in NDUFAF5 and one compound heterozygous for p.Met279Arg. Onset age had a bimodal distribution. The early-onset group (age <3 years) presented with psychomotor delay, seizure, respiratory failure, and hyponatremia. The late-onset group (age ≥5 years) presented with normal development, but slowly progressive dystonia. Combing 25 previously described patients, the p.Met279Arg variant was exclusively identified in Chinese ancestry. Compared with other groups, patients with late-onset homozygous p.Met279Arg were older at onset (P = 0.008), had less developmental delay (P = 0.01), less hyponatremia (P = 0.01), and better prognosis with preserved ambulatory function into early adulthood (P = 0.01). Bilateral basal ganglia necrosis was a common radiological feature, but brainstem and spinal cord involvement was more common with early-onset patients (P = 0.02). A modifier gene analysis showed higher concomitant mutation burden in early-versus late-onset p.Met279Arg homozygous cases (P = 0.04), consistent with more impaired mitochondrial function in fibroblasts from an early-onset case than a late-onset patient. CONCLUSIONS: The p.Met279Arg variant is a common mutation in our population with phenotypic heterogeneity and divergent prognosis based on age at onset. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Distúrbios Distônicos , Hiponatremia , Doença de Leigh , Transtornos dos Movimentos , Pré-Escolar , Humanos , Distúrbios Distônicos/complicações , Hiponatremia/complicações , Doença de Leigh/genética , Doença de Leigh/complicações , Metiltransferases/genética , Proteínas Mitocondriais/genética , Transtornos dos Movimentos/complicações , Mutação/genética , Criança , Adulto Jovem
3.
Chem Biodivers ; 20(12): e202301271, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806964

RESUMO

According to the fusion technique create effective multi-target-directed ligands, in this study, we designed and synthesized a series of benzo[d]thiazol-2-yl)-3-(pyrrolidin-1-yl) or 3-(morph- olino-1-yl)propanamide derivatives, and evaluated their inhibitory potency against MAOs, AChE, BuChE by in vitro enzyme effect assays. Based on activity results, we found that derivatives N-(5-methylbenzo[d]thiazol-2-yl)-3-(pyrrolidin-1-yl)propanamide (2 c) and N-(6-bromobenzo[d]thiazol-2-yl)-3-(pyrrolidin-1-yl)propanamide (2 h) showed good inhibitory potency against BuChE with IC50 values of 15.12 µM and 12.33 µM, respectively. Besides, 2 c and 2 h also exhibited selective MAO-B inhibitory effects with inhibition rates of 60.10 % and 66.30 % at 100 µM, respectively. In contrast, all designed derivatives were poor active against AChE and MAO-A at a concentration of 100 µM. The toxicity analysis in vitro by MTT and AO/EB fluorescence staining confirmed that 2 c and 2 h were nontoxic up to 100 µM. Molecular modeling studies showed that 2 c and 2 h could bind to the active site of BuChE. This research paves the way for further study aimed at designing MAO-B and BuChE inhibitors for the treatment of neurodegenerative disorders.


Assuntos
Doença de Alzheimer , Butirilcolinesterase , Humanos , Butirilcolinesterase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/química , Monoaminoxidase , Benzotiazóis/farmacologia , Morfolinas , Relação Estrutura-Atividade , Estrutura Molecular , Simulação de Acoplamento Molecular
4.
J Biomed Sci ; 29(1): 40, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705979

RESUMO

BACKGROUND: Tight junctions (TJ) are multi-protein complexes that hold epithelial cells together and form structural and functional barriers for maintaining proper biological activities. Dual specificity phosphatase 3 (DUSP3), a suppressor of multiple protein tyrosine (Tyr) kinases, is decreased in lung cancer tissues. Here we demonstrated the role of DUSP3 in regulation of epithelial TJ. METHODS: Barrier functions of TJ were examined in wild-type or DUSP3-deficient lung epithelial cells. Animal and clinical data were analyzed for the association between DUSP3 deficiency and lung cancer progression. Proximity ligation assay, immunoblotting, and phosphatase assay were performed to study the effect of DUSP3 on the TJ protein occludin (OCLN). Mutations of Tyr residues on OCLN showed the role of Tyr phosphorylation in regulating OCLN. RESULTS: Compared to those of the DUSP3-expressing cells, we found the expression and distribution of ZO-1, a TJ-anchoring molecule, were abnormal in DUSP3-deficient cells. OCLN had an increased phosphorylation level in DUSP3-deficient cells. We identified that OCLN is a direct substrate of DUSP3. DUSP3 regulated OCLN ubiquitination and degradation through decreasing OCLN tyrosine phosphorylation directly or through suppressing focal adhesion kinase, the OCLN kinase. CONCLUSION: Our study revealed that DUSP3 is an important TJ regulatory protein and its decrease may be involved in progression of epithelial cancers.


Assuntos
Neoplasias Pulmonares , Junções Íntimas , Animais , Fosfatase 3 de Especificidade Dupla/genética , Fosfatase 3 de Especificidade Dupla/metabolismo , Neoplasias Pulmonares/metabolismo , Ocludina/genética , Ocludina/metabolismo , Ocludina/farmacologia , Fosforilação , Junções Íntimas/genética , Tirosina/metabolismo , Tirosina/farmacologia , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
5.
Acta Pharmacol Sin ; 43(12): 3096-3111, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36229602

RESUMO

Natural products (NPs) and their structural analogs represent a major source of novel drug development for disease prevention and treatment. The development of new drugs from NPs includes two crucial aspects. One is the discovery of NPs from medicinal plants/microorganisms, and the other is the evaluation of the NPs in vivo at various physiological and pathological states. The heterogeneous spatial distribution of NPs in medicinal plants/microorganisms or in vivo can provide valuable information for drug development. However, few molecular imaging technologies can detect thousands of compounds simultaneously on a label-free basis. Over the last two decades, mass spectrometry imaging (MSI) methods have progressively improved and diversified, thereby allowing for the development of various applications of NPs in plants/microorganisms and in vivo NP research. Because MSI allows for the spatial mapping of the production and distribution of numerous molecules in situ without labeling, it provides a visualization tool for NP research. Therefore, we have focused this mini-review on summarizing the applications of MSI technology in discovering NPs from medicinal plants and evaluating NPs in preclinical studies from the perspective of new drug research and development (R&D). Additionally, we briefly reviewed the factors that should be carefully considered to obtain the desired MSI results. Finally, the future development of MSI in new drug R&D is proposed.


Assuntos
Produtos Biológicos , Espectrometria de Massas/métodos , Plantas , Pesquisa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
6.
J Cell Sci ; 132(17)2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31391241

RESUMO

Internalization of macromolecules and membrane into cells through endocytosis is critical for cellular growth, signaling and plasma membrane (PM) tension homeostasis. Although endocytosis is responsive to both biochemical and physical stimuli, how physical cues modulate endocytic pathways is less understood. Contrary to the accumulating discoveries on the effects of increased PM tension on endocytosis, less is known about how a decrease of PM tension impacts on membrane trafficking. Here, we reveal that an acute decrease of PM tension results in phosphatidic acid (PA) production, F-actin and phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2]-enriched dorsal membrane ruffling and subsequent macropinocytosis in myoblasts. The PA production induced by decreased PM tension depends on phospholipase D2 (PLD2) activation via PLD2 nanodomain disintegration. Furthermore, the 'decreased PM tension-PLD2-macropinocytosis' pathway is prominent in myotubes, reflecting a potential mechanism of PM tension homeostasis upon intensive muscle stretching and relaxation. Together, we identify a new mechanotransduction pathway that converts an acute decrease in PM tension into PA production and then initiates macropinocytosis via actin and PI(4,5)P2-mediated processes.


Assuntos
Fosfolipase D/metabolismo , Pinocitose/fisiologia , Actinas/metabolismo , Animais , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Ativação Enzimática , Fenômenos Mecânicos , Mecanotransdução Celular , Microdomínios da Membrana/enzimologia , Microdomínios da Membrana/metabolismo , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Pressão Osmótica
7.
PLoS Genet ; 12(9): e1006262, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27588417

RESUMO

To maintain a particular cell fate, a unique set of genes should be expressed while another set is repressed. One way to repress gene expression is through Polycomb group (PcG) proteins that compact chromatin into a silent configuration. In addition to cell fate maintenance, PcG proteins also maintain normal cell physiology, for example cell cycle. In the absence of PcG, ectopic activation of the PcG-repressed genes leads to developmental defects and malignant tumors. Little is known about the molecular nature of ectopic gene expression; especially what differentiates expression of a given gene in the orthotopic tissue (orthotopic expression) and the ectopic expression of the same gene due to PcG mutations. Here we present that ectopic gene expression in PcG mutant cells specifically requires dBRWD3, a negative regulator of HIRA/Yemanuclein (YEM)-mediated histone variant H3.3 deposition. dBRWD3 mutations suppress both the ectopic gene expression and aberrant tissue overgrowth in PcG mutants through a YEM-dependent mechanism. Our findings identified dBRWD3 as a critical regulator that is uniquely required for ectopic gene expression and aberrant tissue overgrowth caused by PcG mutations.


Assuntos
Ciclo Celular/genética , Diferenciação Celular/genética , Proteínas de Drosophila/genética , Proteínas do Grupo Polycomb/genética , Fatores de Transcrição/genética , Animais , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Cromatina/genética , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/biossíntese , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Olho/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Chaperonas de Histonas/biossíntese , Chaperonas de Histonas/genética , Histonas/genética , Discos Imaginais/crescimento & desenvolvimento , Discos Imaginais/metabolismo , Mutação , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Proteínas do Grupo Polycomb/biossíntese , Fatores de Transcrição/biossíntese
8.
Hum Mol Genet ; 24(19): 5542-54, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26199319

RESUMO

Skeletal muscle requires adequate membrane trafficking and remodeling to maintain its normal structure and functions. Consequently, many human myopathies are caused by mutations in membrane trafficking machinery. The large GTPase dynamin-2 (Dyn2) is best known for catalyzing membrane fission during clathrin-mediated endocytosis (CME), which is critical for cell signaling and survival. Despite its ubiquitous expression, mutations of Dyn2 are associated with two tissue-specific congenital disorders: centronuclear myopathy (CNM) and Charcot-Marie-Tooth (CMT) neuropathy. Several disease models for CNM-Dyn2 have been established to study its pathogenic mechanism; yet the cellular and biochemical effects of these mutations are still not fully understood. Here we comprehensively compared the biochemical activities of disease-associated Dyn2 mutations and found that CNM-Dyn2 mutants are hypermorphic with enhanced membrane fission activity, whereas CMT-Dyn2 is hypomorphic. More importantly, we found that the expression of CNM-Dyn2 mutants does not impair CME in myoblast, but leads to T-tubule fragmentation in both C2C12-derived myotubes and Drosophila body wall muscle. Our results demonstrate that CNM-Dyn2 mutants are gain-of-function mutations, and their primary effect in muscle is T-tubule disorganization, which explains the susceptibility of muscle to Dyn2 hyperactivity.


Assuntos
Doença de Charcot-Marie-Tooth/patologia , Proteínas de Drosophila/genética , Drosophila/metabolismo , Dinamina II/genética , Mutação , Miopatias Congênitas Estruturais/patologia , Animais , Linhagem Celular , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/metabolismo , Clatrina/metabolismo , Drosophila/genética , Proteínas de Drosophila/metabolismo , Dinamina II/metabolismo , Endocitose , Humanos , Camundongos , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/metabolismo
9.
Proc Natl Acad Sci U S A ; 111(46): 16568-73, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25359212

RESUMO

Neurons remodel their connectivity in response to various insults, including microtubule disruption. How neurons sense microtubule disassembly and mount remodeling responses by altering genetic programs in the soma are not well defined. Here we show that in response to microtubule disassembly, the Caenorhabditis elegans PLM neuron remodels by retracting its synaptic branch and overextending the primary neurite. This remodeling required RHGF-1, a PDZ-Rho guanine nucleotide exchange factor (PDZ-RhoGEF) that was associated with and inhibited by microtubules. Independent of the myosin light chain activation, RHGF-1 acted through Rho-dependent kinase LET-502/ROCK and activated a conserved, retrograde DLK-1 MAPK (DLK-1/dual leucine zipper kinase) pathway, which triggered synaptic branch retraction and overgrowth of the PLM neurite in a dose-dependent manner. Our data represent a neuronal remodeling paradigm during development that reshapes the neural circuit by the coordinated removal of the dysfunctional synaptic branch compartment and compensatory extension of the primary neurite.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/fisiologia , Fatores de Troca do Nucleotídeo Guanina/fisiologia , MAP Quinase Quinase Quinases/fisiologia , Mecanorreceptores/fisiologia , Microtúbulos/metabolismo , Regeneração Nervosa/fisiologia , Neurônios/fisiologia , Animais , Axônios/ultraestrutura , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Forma Celular , Colchicina/farmacologia , Ativação Enzimática , Genes Reporter , Larva , Sistema de Sinalização das MAP Quinases/fisiologia , Mecanorreceptores/ultraestrutura , Microtúbulos/efeitos dos fármacos , Microtúbulos/ultraestrutura , Mutação , Neuritos/metabolismo , Neuritos/ultraestrutura , Neurônios/ultraestrutura , Paclitaxel/farmacologia , Interferência de RNA , Proteínas Recombinantes de Fusão/metabolismo , Tato/fisiologia , Tubulina (Proteína)/deficiência , Tubulina (Proteína)/genética , Tubulina (Proteína)/fisiologia , Moduladores de Tubulina/farmacologia , Quinases Associadas a rho/fisiologia
10.
J Cell Sci ; 127(Pt 12): 2615-20, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24706946

RESUMO

Small GTPase ADP-ribosylation factors (ARFs) are key regulators of membrane trafficking and their activities are determined by guanine-nucleotide-binding status. In Saccharomyces cerevisiae, Arl1p, an ARF-like protein, is responsible for multiple trafficking pathways at the Golgi. The GTP-hydrolysis activity of Arl1p is stimulated by its GTPase-activating protein Gcs1p, and binding with its effector Imh1p protects Arl1p from premature inactivation. However, the mechanism involved in the timing of Arl1p inactivation is unclear. Here, we demonstrate that another Arl1p effector, the lipid flippase Drs2p, is required for Gcs1p-stimulated inactivation of Arl1p. Drs2p is known to be activated by Arl1p and is involved in vesicle formation through its ability to create membrane asymmetry. We found that the flippase activity of Drs2p is required for proper membrane targeting of Gcs1p in vivo. Through modification of the membrane environment, Drs2p promotes the affinity of Gcs1p for the Golgi, where it binds to active Arl1p. Together, Imh1p and Drs2p modulate the activity of Gcs1p by timing its interaction with Arl1p, hence providing feedback regulation of Arl1p activity.


Assuntos
ATPases Transportadoras de Cálcio/fisiologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/enzimologia , Proteínas de Transporte Vesicular/metabolismo , Membrana Celular , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática , Retroalimentação Fisiológica , Proteínas Ativadoras de GTPase/metabolismo , Guanosina Trifosfato , Hidrólise , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico
11.
Proc Natl Acad Sci U S A ; 110(8): E668-77, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23345439

RESUMO

ADP ribosylation factors (Arfs) are the central regulators of vesicle trafficking from the Golgi complex. Activated Arfs facilitate vesicle formation through stimulating coat assembly, activating lipid-modifying enzymes and recruiting tethers and other effectors. Lipid translocases (flippases) have been implicated in vesicle formation through the generation of membrane curvature. Although there is no evidence that Arfs directly regulate flippase activity, an Arf-guanine-nucleotide-exchange factor (GEF) Gea2p has been shown to bind to and stimulate the activity of the flippase Drs2p. Here, we provide evidence for the interaction and activation of Drs2p by Arf-like protein Arl1p in yeast. We observed that Arl1p, Drs2p and Gea2p form a complex through direct interaction with each other, and each interaction is necessary for the stability of the complex and is indispensable for flippase activity. Furthermore, we show that this Arl1p-Drs2p-Gea2p complex is specifically required for recruiting golgin Imh1p to the Golgi. Our results demonstrate that activated Arl1p can promote the spatial modulation of membrane organization at the trans-Golgi network through interacting with the effectors Gea2p and Drs2p.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas de Membrana/fisiologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Rede trans-Golgi/metabolismo , Fatores de Ribosilação do ADP/fisiologia , Membrana Celular/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Fosfatidilserinas/metabolismo , Transporte Proteico , Saccharomyces cerevisiae/metabolismo , Técnicas do Sistema de Duplo-Híbrido
12.
Biomed Environ Sci ; 29(7): 534-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27554125

RESUMO

Dyslipidemia is a risk factor for cardiovascular diseases (CVDs) in patients with diabetes, and non-high-density lipoprotein cholesterol (non-HDL-C) is a better predictor of CVDs than low-density lipoprotein cholesterol (LDL-C) in patients with diabetes. Therefore, we aimed to investigate the distribution of non-HDL-C and the prevalence of high non-HDL-C level in Chinese patients with diabetes mellitus and identify the associated risk factors. Non-HDL-C concentration positively correlated with total cholesterol, triglycerides, and LDL-C concentrations. Although both non-HDL-C and LDL-C concentration both related positively with TC concentration, the magnitude of correlation was relatively higher for non-HDL-C. The prevalence of high non-HDL-C (⋝4.14 mmol/L) was higher in two age groups (55-64 years: 46.7%; 65-79 years: 47.3%) than other age groups (18-24 years: 4.2%; 25-34 years: 43.6%; 35-44 years: 38.1%; 45-54 years: 41.0%). It was also higher among overweight (45.1%), generally obese (50.9%), or abdominally obese (47.3%) subjects, compared with normal weight subjects (34.5%). The risk of high non-HDL-C increased with advancing age. Both general obesity [odds ratio (OR)=1.488, 95% confidence interval (CI): 1.003-2.209] and abdominal obesity (OR=1.561, 95% CI: 1.101-2.214) were significantly associated with high non-HDL-C levels.


Assuntos
Diabetes Mellitus/epidemiologia , Diabetes Mellitus/etiologia , Hipercolesterolemia/epidemiologia , Adolescente , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
13.
Cell Physiol Biochem ; 36(4): 1382-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26159618

RESUMO

BACKGROUND/AIMS: FOXQ1 overexpression has been reported to enhance tumor growth and invasion. However, the biological function of FOXQ1 and the mechanism underlying its upregulation in gastric cancer (GC) remain unknown. METHODS: QPCR was used to detect the expression of miR-1271 and FOXQ1 in specimens from GC patients. FOXQ1-siRNA, and miR- 1271 mimics and inhibitor were transfected into human MGC-803 and SGC-7901 cells. The transwell assay was used to examine the cell invasive ability. The regulation mechanism was confirmed by luciferase reporter assay. Markers of epithelial-mesenchymal transition (EMT) were detected by western blot analysis. RESULTS: MiR-1271 was downregulated in both GC tissues and GC cell lines. The expression of miR-1271 was inversely correlated with tumor size (P = 0.017), tumor stage (P = 0.035), lymph node metastasis (P = 0.018), and TNM stage (P = 0.025). Ectopic expression of miR-1271 dramatically suppressed GC cell proliferation, invasion, and EMT. Furthermore, FOXQ1 was identified as a direct target of miR-1271. Knockdown of FOXQ1 inhibited GC cell malignant behavior, whereas FOXQ1 overexpression partially restored the suppression effects of miR-1271. Additionally, miR-1271 expression was negatively correlated with FOXQ1 in GC tissues. CONCLUSIONS: MiR-1271 inhibits cell proliferation, invasion, and EMT in GC by directly suppressing FOXQ1 expression.


Assuntos
Transição Epitelial-Mesenquimal , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Invasividade Neoplásica/genética , Neoplasias Gástricas/genética , Estômago/patologia , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Neoplasias Gástricas/patologia
14.
Sensors (Basel) ; 15(9): 21377-93, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26343673

RESUMO

The main approach for a Wi-Fi indoor positioning system is based on the received signal strength (RSS) measurements, and the fingerprinting method is utilized to determine the user position by matching the RSS values with the pre-surveyed RSS database. To build a RSS fingerprint database is essential for an RSS based indoor positioning system, and building such a RSS fingerprint database requires lots of time and effort. As the range of the indoor environment becomes larger, labor is increased. To provide better indoor positioning services and to reduce the labor required for the establishment of the positioning system at the same time, an indoor positioning system with an appropriate spatial interpolation method is needed. In addition, the advantage of the RSS approach is that the signal strength decays as the transmission distance increases, and this signal propagation characteristic is applied to an interpolated database with the Kriging algorithm in this paper. Using the distribution of reference points (RPs) at measured points, the signal propagation model of the Wi-Fi access point (AP) in the building can be built and expressed as a function. The function, as the spatial structure of the environment, can create the RSS database quickly in different indoor environments. Thus, in this paper, a Wi-Fi indoor positioning system based on the Kriging fingerprinting method is developed. As shown in the experiment results, with a 72.2% probability, the error of the extended RSS database with Kriging is less than 3 dBm compared to the surveyed RSS database. Importantly, the positioning error of the developed Wi-Fi indoor positioning system with Kriging is reduced by 17.9% in average than that without Kriging.

15.
J Cell Sci ; 125(Pt 19): 4586-96, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22767516

RESUMO

Golgins play diverse roles in regulating the structure and function of the Golgi. The yeast golgin Imh1p is targeted to the trans-Golgi network (TGN) through interaction of its GRIP domain with GTP-bound Arl1p. Recycling of Arl1p and Imh1p to the cytosol requires the hydrolysis of GTP bound to Arl1p; however, the point at which GTP hydrolysis occurs remains unknown. Here, we report that self-interaction of Imh1p plays a role in modulating spatial inactivation of Arl1p. Deletion of IMH1 in yeast decreases the amount of the GTP-bound Arl1p and results in less Arl1p residing on the TGN. Biochemically, purified Imh1p competes with Gcs1p, an Arl1p GTPase-activating protein (GAP), for binding to Arl1p, thus interfering with the GAP activity of Gcs1p toward Arl1p. Furthermore, we demonstrate that the self-interaction of Imh1p attenuates the Gcs1p-dependent GTP hydrolysis of Arl1p. Thus, we propose that the golgin Imh1p serves as a feedback regulator to modulate the GTP hydrolysis of Arl1p.


Assuntos
Ligação Competitiva , Proteínas de Ligação a DNA/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Complexo de Golgi/enzimologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Proteínas de Transporte Vesicular/metabolismo , Ativação Enzimática , Deleção de Genes , Técnicas de Inativação de Genes , Guanosina Trifosfato/metabolismo , Hidrólise , Modelos Biológicos , Proteínas Monoméricas de Ligação ao GTP/química , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Ligação Proteica , Multimerização Proteica , Estabilidade Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Relação Estrutura-Atividade , Proteínas de Transporte Vesicular/química , Rede trans-Golgi/metabolismo
16.
BMC Infect Dis ; 14: 301, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24894341

RESUMO

BACKGROUND: Since the end of the 1990s, the incidence of hemorrhagic fever with renal syndrome (HFRS) has been increasing dramatically in Changchun, northeastern China. However, it is unknown which, and how, underlying risk factors have been involved in the reemergence of the disease. METHODS: Data on HFRS cases at the county scale were collected from 1998 to 2012. Data on livestock husbandry including the numbers of large animals (cattle, horses, donkeys and mules), sheep, and deer, and on climatic and land cover variables were also collected. Epidemiological features, including the spatial, temporal and human patterns of disease were characterized. The potential factors related to spatial heterogeneity and temporal trends were analyzed using standard and time-series Poisson regression analysis, respectively. RESULTS: Annual incidence varied among the 10 counties. Shuangyang County in southeastern Changchun had the highest number of cases (1,525 cases; 35.9% of all cases), but its population only accounted for 5.6% of the total population. Based on seasonal pattern in HFRS incidence, two epidemic phases were identified. One was a single epidemic peak at the end of each year from 1988 to 1997 and the other consisted of dual epidemic peaks at both the end and the beginning of each year from 1998 to the end of the study period. HFRS incidence was higher in males compared to females, and most of the HFRS cases occurred in peasant populations. The results of the Poisson regression analysis indicated that the spatial distribution and the increasing incidence of HFRS were significantly associated with livestock husbandry and climate factors, particularly with deer cultivation. CONCLUSIONS: Our results indicate that the re-emergence of HFRS in Changchun has been accompanied by changing seasonal patterns over the past 25 years. Integrated measures focusing on areas related to local livestock husbandry could be helpful for the prevention and control of HFRS.


Assuntos
Criação de Animais Domésticos , Febre Hemorrágica com Síndrome Renal/epidemiologia , Animais , Bovinos , China/epidemiologia , Clima , Febre Hemorrágica com Síndrome Renal/etiologia , Cavalos , Humanos , Incidência , Gado , Análise de Regressão , Fatores de Risco , Ovinos
17.
Bioessays ; 34(8): 643-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22592980

RESUMO

Whereas clathrin-mediated endocytosis (CME) exists in all eukaryotic cells, we first detect classical dynamin in Ichthyosporid, a single-cell, metazoan precursor. Based on a key functional residue in its pleckstrin homology domain, we speculate that the evolution of metazoan dynamin coincided with the specialized need for regulated CME during neurotransmission.


Assuntos
Clatrina/química , Dinaminas/química , Endocitose , Evolução Molecular , Sequência de Aminoácidos , Animais , Proteínas Sanguíneas/química , Dinaminas/classificação , Humanos , Dados de Sequência Molecular , Neurônios/química , Especificidade de Órgãos , Fosfoproteínas/química , Filogenia , Isoformas de Proteínas/química , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos
18.
Lipids Health Dis ; 13: 122, 2014 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-25086650

RESUMO

BACKGROUND: In China, even though the prevalence of dyslipidemia among adults increased yearly and dyslipidemia being an important risk factor for cardiovascular diseases among the Chinese population, however, the awareness, treatment and control of dyslipidemia are at low levels, and only limited studies on the influence factors associated with the awareness, treatment and control dyslipidemia in China have been carried out. METHODS: The analysis was based on a representative sample of 7138 adult subjects aged 18~79 years recruited from a cross-sectional study of chronic disease and risk factors among adults in the Jilin province in 2012. Chi-square test was used to compare the rates of dyslipidemia awareness, treatment and control between different characteristics of participants. Multiple logistic regression analyses were performed separately for each group to explore the associations between participants' characteristics and dyslipidemia awareness, treatment and control. RESULTS: Among participants with dyslipidemia, 11.6% were aware of the diagnosis, 8.4% were receiving treatment, and 34.8% had dyslipidemia controlled. Increase in age and BMI ≥ 24 kg/m2 were by far the strongest risk factors associated with better awareness and treatment of dyslipidemia. Retirees were more likely to be aware of their dyslipidemia condition (OR=1.255; 95% CI: 1.046, 1.506) and to be receiving treatment (OR=1.367; 95% CI: 1.114, 1.676) than manual workers. A family history of dyslipidemia increased the likelihood of awareness (OR=3.620; 95% CI: 2.816, 4.653) and treatment (OR=3.298; 95% CI: 2.488, 4.371) of dyslipidemia. Alcohol drinking and physical activity were associated with a lower level of awareness and treatment.Cigarette smokers (OR=0.501; 95% CI: 0.349, 0.719) and those with BMI ≥ 24 kg/m2 (OR=0.480; 95% CI: 0.326, 0.706) who received treatment were also associated with poor dyslipidemia control. CONCLUSION: Our study highlights low levels of awareness, poor treatment and control of dyslipidemia among adults aged 18~79 in the Jilin province. Promotion of healthy lifestyles and establishment of a comprehensive strategy of screening, treatment and control of dyslipidemia is needed to reduce or prevent the risk of cardiovascular disease in the Jilin province.


Assuntos
Dislipidemias/epidemiologia , Adolescente , Adulto , Idoso , China/epidemiologia , Estudos Transversais , Dislipidemias/etiologia , Dislipidemias/terapia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/complicações , Sobrepeso/epidemiologia , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Adulto Jovem
19.
Proc Natl Acad Sci U S A ; 108(26): E234-42, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21670293

RESUMO

Dynamin 1 (Dyn1) and Dyn2 are neuronal and ubiquitously expressed isoforms, respectively, of the multidomain GTPase required for clathrin-mediated endocytosis (CME). Although they are 79% identical, Dyn1 and Dyn2 are not fully functionally redundant. Through direct measurements of basal and assembly-stimulated GTPase activities, membrane binding, self-assembly, and membrane fission on planar and curved templates, we have shown that Dyn1 is an efficient curvature generator, whereas Dyn2 is primarily a curvature sensor. Using Dyn1/Dyn2 chimeras, we identified the lipid-binding pleckstrin homology domain as being responsible for the differential in vitro properties of these two isoforms. Remarkably, their in vitro activities were reversed by a single amino acid change in the membrane-binding variable loop 3. Reconstitution of KO mouse embryo fibroblasts showed that both the pleckstrin homology and the Pro/Arg-rich domains determine the differential abilities of these two isoforms to support CME. These domains are specific to classical dynamins and are involved in regulating their activity. Our findings reveal opportunities for fundamental differences in the regulation of Dyn1, which mediates rapid endocytosis at the synapse, vs. Dyn2, which regulates early and late events in CME in nonneuronal cells.


Assuntos
Dinaminas/fisiologia , Isoformas de Proteínas/fisiologia , Animais , Membrana Celular , Dinaminas/química , Endocitose , Camundongos , Camundongos Knockout , Isoformas de Proteínas/química
20.
Sci Rep ; 14(1): 12799, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834662

RESUMO

Lymphocyte subsets are the most intuitive expression of the body's immune ability, and the lymphocyte-to-monocyte ratio (LMR) also clearly reflect the degree of chronic inflammation activity. The purpose of this study is to investigate their predictive value of lymphocyte subsets and LMR to neoadjuvant therapy (NAT) efficacy in breast cancer patients. In this study, lymphocyte subsets and LMR were compared between breast cancer patients (n = 70) and benign breast tumor female populations (n = 48). Breast cancer patients were treated with NAT, and the chemotherapy response of the breast was evaluated using established criteria. The differences in lymphocyte subsets and LMR were also compared between pathological complete response (pCR) and non-pCR patients before and after NAT. Finally, data were analyzed using SPSS. The analytical results demonstrated that breast cancer patients showed significantly lower levels of CD3 + T cells, CD4 + T cells, CD4 + /CD8 + ratio, NK cells, and LMR compared to benign breast tumor women (P < 0.05). Among breast cancer patients, those who achieved pCR had higher levels of CD4 + T cells, NK cells, and LMR before NAT (P < 0.05). NAT increased CD4 + /CD8 + ratio and decreased CD8 + T cells in pCR patients (P < 0.05). Additionally, both pCR and non-pCR patients exhibited an increase in CD3 + T cells and CD4 + T cells after treatment, but the increase was significantly higher in pCR patients (P < 0.05). Conversely, both pCR and non-pCR patients experienced a decrease in LMR after treatment. However, this decrease was significantly lower in pCR patients (P < 0.05). These indicators demonstrated their predictive value for therapeutic efficacy. In conclusion, breast cancer patients experience tumor-related immunosuppression and high chronic inflammation response. But this phenomenon can be reversed to varying degrees by NAT. It has been found that lymphocyte subsets and LMR have good predictive value for pCR. Therefore, these markers can be utilized to identify individuals who are insensitive to NAT early on, enabling the adjustment of treatment plans and achieving precise breast cancer treatment.


Assuntos
Neoplasias da Mama , Subpopulações de Linfócitos , Monócitos , Terapia Neoadjuvante , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/terapia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Neoplasias da Mama/sangue , Feminino , Terapia Neoadjuvante/métodos , Pessoa de Meia-Idade , Subpopulações de Linfócitos/imunologia , Adulto , Resultado do Tratamento , Idoso , Contagem de Linfócitos
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