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1.
Microb Pathog ; 188: 106549, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281605

RESUMO

The five epidermal growth factor-like domains (EGF) of Eimeria tenella microneme protein 8 (EtMIC8) (EtMIC8-EGF) plays a vital role in host cell attachment and invasion. These processes require interactions between parasite proteins and receptors on the surface of host cells. In this study, five chicken membrane proteins potentially interacting with EtMIC8-EGF were identified using the GST pull-down assay and mass spectrometry analysis, and only chicken (Gallus gallus) epithelial cell adhesion molecule (EPCAM) could bind to EtMIC8-EGF. EPCAM-specific antibody and recombinant EPCAM protein (rEPCAM) inhibited the EtMIC8-EGF binding to host cells in a concentration-dependent manner. Furthermore, the rEPCAM protein showed a binding activity to sporozoites in vitro, and a significant reduction of E. tenella invasion in DF-1 cells was further observed after pre-incubation of sporozoites with rEPCAM. The specific anti-EPCAM antibody further significantly decreased weight loss, lesion score and oocyst output during E. tenella infection, displaying partial inhibition of E. tenella infection. These results indicate that chicken EPCAM is an important EtMIC8-interacting host protein involved in E. tenella-host cell adhesion and invasion. The findings will contribute to a better understanding of the role of adhesion-associated microneme proteins in E. tenella.


Assuntos
Coccidiose , Eimeria tenella , Doenças das Aves Domésticas , Animais , Eimeria tenella/química , Eimeria tenella/metabolismo , Molécula de Adesão da Célula Epitelial/metabolismo , Galinhas , Proteínas de Protozoários , Fator de Crescimento Epidérmico/metabolismo , Proteínas Recombinantes , Esporozoítos/metabolismo , Coccidiose/veterinária , Coccidiose/parasitologia , Doenças das Aves Domésticas/parasitologia
2.
Opt Lett ; 49(11): 3279-3282, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824383

RESUMO

AlGaN-based solar-blind ultraviolet avalanche detectors have huge potentials in the fields of corona discharge monitoring, biological imaging, etc. Here, we study the impact of the heterojunction polarization-related effects on the AlGaN-based solar-blind ultraviolet avalanche detectors. Our work confirms that the polarization heterojunction is beneficial to reducing avalanche bias and lifting avalanche gain by improving the electric field in the depletion region, while the polarization-induced fixed charges will lead to a redistribution of the electrons, in turn shielding the charges and weakening the electric field enhancement effect. This shielding effect will need external bias to eliminate, and that is why the polarization heterojunction cannot work at relatively low bias but has an enhancement effect at high bias. Controlling the doping level between the hetero-interface can affect the shielding effect. An unintentionally doped polarization heterojunction can effectively reduce the shielding effect, thus reducing the avalanche bias. The conclusions also hold true for the negative polarization regime. We believe our findings can provide some useful insights for the design of the AlGaN-based solar-blind ultraviolet detectors.

3.
Opt Lett ; 49(14): 4030-4033, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008769

RESUMO

In this work, we propose a highly reflective Ni/Pt/Al p-electrode for AlGaN-based deep ultraviolet (DUV) light-emitting diodes (LEDs) with a wavelength of 276 nm. AlGaN-based DUV LEDs with traditional Al-based reflectivity electrodes suffer from device degradation and wall-plug efficiency (WPE) droop due to the Al diffusion during electrode annealing. By inserting a Pt layer between the Ni contact layer and the Al reflective layer, the contact characteristics of the p-electrode can be optimized by blocking the diffusion of the O and Al atoms, maintaining a high reflectivity of over 80% near 280 nm. Compared to the AlGaN-based DUV LEDs with Ni/Au traditional p-electrodes and Ni/Al traditional reflective p-electrodes, the WPE of the LED with a highly reflective Ni/Pt/Al p-electrode is improved by 10.3% and 30.5%, respectively. Besides, compared to the other novel reflective p-electrodes using multiple annealing or evaporation processes reported for the AlGaN-based DUV LEDs, we provide a new, to the best of our knowledge, optimization method for single evaporation and annealing p-type reflective electrodes, featured with a simpler and more convenient process flow.

4.
Arterioscler Thromb Vasc Biol ; 43(4): 562-580, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36756879

RESUMO

BACKGROUND: Postprandial dyslipidemia is a causative risk factor for cardiovascular disease. The majority of absorbed dietary lipids are packaged into chylomicron and then delivered to circulation. Previous studies showed that Surf4 (surfeit locus protein 4) mediates very low-density lipoprotein secretion from hepatocytes. Silencing hepatic Surf4 markedly reduces the development of atherosclerosis in different mouse models of atherosclerosis without causing hepatic steatosis. However, the role of Surf4 in chylomicron secretion is unknown. METHODS: We developed inducible intestinal-specific Surf4 knockdown mice (Surf4IKO) using Vil1Cre-ERT2 and Surf4flox mice. Metabolic cages were used to monitor mouse metabolism. Enzymatic kits were employed to measure serum and tissue lipid levels. The expression of target genes was detected by qRT-PCR and Western Blot. Transmission electron microscopy and radiolabeled oleic acid were used to assess the structure of enterocytes and intestinal lipid absorption and secretion, respectively. Proteomics was performed to determine changes in protein expression in serum and jejunum. RESULTS: Surf4IKO mice, especially male Surf4IKO mice, displayed significant body weight loss, increased mortality, and reduced metabolism. Surf4IKO mice exhibited lipid accumulation in enterocytes and impaired fat absorption and secretion. Lipid droplets and small lipid vacuoles were accumulated in the cytosol and the endoplasmic reticulum lumen of the enterocytes of Surf4IKO mice, respectively. Surf4 colocalized with apoB and co-immunoprecipitated with apoB48 in differentiated Caco-2 cells. Intestinal Surf4 deficiency also significantly reduced serum triglyceride, cholesterol, and free fatty acid levels in mice. Proteomics data revealed that diverse pathways were altered in Surf4IKO mice. In addition, Surf4IKO mice had mild liver damage, decreased liver size and weight, and reduced hepatic triglyceride levels. CONCLUSIONS: Our findings demonstrate that intestinal Surf4 plays an essential role in lipid absorption and chylomicron secretion and suggest that the therapeutic use of Surf4 inhibition requires highly cell/tissue-specific targeting.


Assuntos
Aterosclerose , Mucosa Intestinal , Humanos , Masculino , Animais , Camundongos , Mucosa Intestinal/metabolismo , Células CACO-2 , Absorção Intestinal/fisiologia , Gorduras na Dieta , Quilomícrons/metabolismo , Metabolismo dos Lipídeos/genética , Triglicerídeos/metabolismo , Aterosclerose/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
5.
Parasitol Res ; 123(1): 45, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095706

RESUMO

Difficulties of in vitro culture and genetic manipulation of Eimeria tenella have hindered the screening of virulence factors in this parasite. In this study, the E. tenella rhoptry protein 30 (EtROP30) was expressed in Toxoplasma gondii (RH∆Ku80-EtROP30), and its effect on the proliferation and virulence of parasites was investigated. The results revealed that the expression of EtROP30 had no impact on the invasion and egress processes. However, the RH∆Ku80-EtROP30 strain formed larger plaques compared to the RH∆Ku80, indicating that the EtROP30 expression promotes T. gondii proliferation. Furthermore, the RH∆Ku80-EtROP30 strain exhibited greater pathogenicity, resulting in earlier mortality and shorter overall survival time compared to RH∆Ku80. These results imply that EtROP30 expression facilitates parasite intracellular proliferation and virulence in mice, suggesting that EtROP30 might be a candidate virulence factor of E. tenella.


Assuntos
Eimeria tenella , Toxoplasma , Animais , Camundongos , Eimeria tenella/genética , Eimeria tenella/metabolismo , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Animais Geneticamente Modificados , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
6.
J Lipid Res ; 62: 100091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34118252

RESUMO

Plasma LDL is produced from catabolism of VLDL and cleared from circulation mainly via the hepatic LDL receptor (LDLR). Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes LDLR degradation, increasing plasma LDL-C levels. Circulating PCSK9 is mainly secreted by the liver, whereas VLDL is exclusively secreted by hepatocytes. However, the mechanism regulating their secretion is not completely understood. Surfeit 4 (Surf4) is a cargo receptor localized in the ER membrane. It recruits cargos into coat protein complex II vesicles to facilitate their secretion. Here, we investigated the role of Surf4 in VLDL and PCSK9 secretion. We generated Surf4 liver-specific knockout mice and found that knockout of Surf4 did not affect PCSK9 secretion, whereas it significantly reduced plasma levels of cholesterol, triglyceride, and lipid-binding protein apolipoprotein B (apoB). In cultured human hepatocytes, Surf4 coimmunoprecipitated and colocalized with apolipoprotein B100, and Surf4 silencing reduced secretion of apolipoprotein B100. Furthermore, knockdown of Surf4 in LDLR knockout (Ldlr-/-) mice significantly reduced triglyceride secretion, plasma levels of apoB and non-HDL-C, and the development of atherosclerosis. However, Surf4 liver-specific knockout mice and Surf4 knockdown in Ldlr-/- mice displayed similar levels of liver lipids and plasma alanine aminotransferase activity as control mice, indicating that inhibition of Surf4 does not cause notable liver damage. Expression of stearoyl-CoA desaturase-1 was also reduced in the liver of these mice, suggesting a reduction in de novo lipogenesis. In summary, hepatic deficiency of Surf4 reduced VLDL secretion and the development of atherosclerosis but did not cause significant hepatic lipid accumulation or liver damage.


Assuntos
Aterosclerose/metabolismo , Lipoproteínas VLDL/metabolismo , Proteínas de Membrana/metabolismo , Animais , Células Cultivadas , Proteínas de Membrana/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9/deficiência , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/deficiência , Receptores de LDL/metabolismo
7.
Dig Dis Sci ; 66(12): 4251-4262, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33528684

RESUMO

BACKGROUND: Whether 7,8-dihydroxyflavone (7,8-DHF), a tyrosine kinase receptor B (TrkB) agonist, modulates colonic smooth muscle motility and/or alleviates constipation has not yet been studied. AIMS: Here, we aimed to determine how 7,8-DHF influences carbachol (CCh)-stimulated contraction of colonic strips and the in vivo effect of 7,8-DHF on constipation. METHODS: Muscle strips were isolated from rat colons for recording contractile tension and performing western blotting. Constipation was induced in rats with loperamide. RESULTS: Although it specifically activated TrkB, 7,8-DHF applied alone neither activated PLCγ1 in the colonic strips nor induced colonic strip contraction. However, 7,8-DHF enhanced CCh-stimulated PLCγ1 activation and strip contraction. The PLCγ1 antagonist U73122 suppressed both CCh-stimulated and 7,8-DHF-enhanced/CCh-stimulated contraction. While clarifying the underlying mechanism, we revealed that 7,8-DHF augmented muscarinic M3 receptor expression in the colonic strips. The M3-selective antagonist tarafenacin specifically inhibited the 7,8-DHF-enhanced/CCh-stimulated contraction of the colonic strips. Since 7,8-DHF increased Akt phosphorylation, and LY294002 (an antagonist of PI3K upstream of Akt) dramatically inhibited both 7,8-DHF-augmented M3 expression and 7,8-DHF-enhanced/CCh-stimulated contractions, we assumed that 7,8-DHF/TrkB/Akt was associated with the modulation of M3 expression in the colonic strips. ANA-12, a specific TrkB antagonist, not only inhibited TrkB activation by 7,8-DHF but also suppressed 7,8-DHF-enhanced cholinergic contraction, 7,8-DHF/CCh-mediated activation of PLCγ1/Akt, and M3 overexpression in colonic strips. In vivo 7,8-DHF, also by promoting intestinal motility and M3 expression, significantly alleviated loperamide-induced functional constipation in rats. CONCLUSIONS: Our results suggest that 7,8-DHF regulates colonic motility possibly via a TrkB/Akt/M3 pathway and may be applicable for alleviating constipation.


Assuntos
Colo/efeitos dos fármacos , Constipação Intestinal/tratamento farmacológico , Defecação/efeitos dos fármacos , Flavonas/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Agonistas Muscarínicos/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Animais , Colo/metabolismo , Colo/fisiopatologia , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/fisiopatologia , Modelos Animais de Doenças , Técnicas In Vitro , Loperamida , Músculo Liso/metabolismo , Músculo Liso/fisiopatologia , Fosfolipase C gama/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Muscarínico M3/agonistas , Receptor Muscarínico M3/metabolismo , Receptor trkB/agonistas , Receptor trkB/metabolismo , Transdução de Sinais
8.
Eur Spine J ; 29(9): 2384-2391, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32725391

RESUMO

PURPOSE: The aim is to propose a novel spinopelvic parameter C7 sacral tilt (C7ST), of which its sum with global tilt (GT) is equal to pelvic incidence (PI), from a geometrical point of view. METHODS: A cohort of 198 patients was recruited and the whole lateral spine and pelvic radiographs were performed. The following sagittal parameters were measured: sagittal vertical axis (SVA), C7 vertical tilt (C7VT), sacral slope (SS), pelvic tilt (PT), PI, GT and C7ST. The correlations between them were analyzed using the Pearson or Spearman correlation coefficient, and simple linear regressions were simultaneously conducted. P < 0.05 was set as the level of significance. RESULTS: Geometric construction by complementary angles revealed that PI = C7ST + GT, GT = PT + C7VT, and C7ST = SS - C7VT. Both C7ST and GT were moderately correlated with PI (R = 0.52 and 0.596, respectively), strongly correlated with SS and PT, respectively (SS = 0.9 * C7ST + 1.15, R = 0.955; PT = 0.87 * GT + 3.86, R = 0.96). The correlation coefficients of the SVA and C7VT, SVA and SS - C7ST, and SVA and GT - PT were 0.935, 0.925 and 0.863, respectively. CONCLUSION: The novel proposed spinopelvic parameter C7ST has the advantages of convenient measurement, reduced error, and extrapolation of other parameters. The greatest significance of proposing C7ST is that pelvic parameters (PI, PT and SS) are converted into spinal parameters (C7ST and GT), which is very helpful for a more intuitive understanding of the progression of spinal sagittal imbalance.


Assuntos
Postura , Sacro , Estudos de Coortes , Humanos , Radiografia , Região Sacrococcígea , Sacro/diagnóstico por imagem
9.
J Cell Biochem ; 120(4): 5713-5721, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30362602

RESUMO

BACKGROUNDS AND AIMS: Increased arterial stiffness may increase cardiovascular morbidity and mortality. Angiotensin II type 1 receptor blocker losartan is potentially useful in controlling the central blood pressure and arterial stiffness in mild to moderate essential hypertension, while the effects of losartan in aged patients with essential hypertension are not entirely investigated. METHODS: The carotid-femoral arterial pulse wave velocity (PWV) was measured in aged patients with essential hypertension. RESULTS: In a cross-sectional study, PWV value was significantly higher in these old patients with essential hypertension, compared with patients without essential hypertension. Logistic regression analysis indicated that age, hypertension duration, and losartan treatment are risk factors of arterial stiffness. In a perspective study, long-term administration of losartan (50 mg/d) remarkably reduced PWV in aged patients with essential hypertension. In a longitudinal study, PWV is an independent predictor of the occurrence of acute coronary syndrome (ACS) in elderly patients with essential hypertension by using multivariate analysis. Further, the ACS occurrence was reduced by long-term administration of losartan in aged patients with essential hypertension, compared with the old hypertensive patients without taking losartan. CONCLUSION: Losartan treatment is a negative risk factor of arterial stiffness and reduces the risk of ACS in aged patients with essential hypertension.


Assuntos
Síndrome Coronariana Aguda/prevenção & controle , Anti-Hipertensivos/uso terapêutico , Hipertensão Essencial/complicações , Losartan/uso terapêutico , Análise de Onda de Pulso/métodos , Rigidez Vascular/efeitos dos fármacos , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/etiologia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico
10.
J Appl Toxicol ; 38(3): 408-417, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29134676

RESUMO

Plague has led to millions of deaths in history and outbreaks continue to the present day. The efficacy limitations and safety concerns of the existing killed whole cell and live-attenuated vaccines call for the development of new vaccines. In this study, we evaluated the immunogenicity and safety of a novel subunit plague vaccine, comprising native F1 antigen and recombinant V antigen. The cynomolgus macaques in low- and high-dose vaccine groups were vaccinated at weeks 0, 2, 4 and 6, at dose levels of 15 µg F1 + 15 µg rV and 30 µg F1 + 30 µg rV respectively. Specific antibodies and interferon-γ and interleukin-2 expression in lymphocytes were measured. For safety, except for the general toxicity and local irritation, we made a systematic immunotoxicity study on the vaccine including immunostimulation, autoimmunity and anaphylactic reaction. The vaccine induced high levels of serum anti-F1 and anti-rV antibodies, and caused small increases of interferon-γ and interleukin-2 in monkeys. The vaccination led to a reversible increase in the number of peripheral blood eosinophils, the increases in serum IgE level in a few animals and histopathological change of granulomas at injection sites. The vaccine had no impact on general conditions, most clinical pathology parameters, percentages of T-cell subsets, organ weights and gross pathology of treated monkeys and had passable local tolerance. The F1 + rV subunit plague vaccine can induce very strong humoral immunity and low level of cellular immunity in cynomolgus macaques and has a good safety profile.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Imunidade Humoral/efeitos dos fármacos , Imunogenicidade da Vacina , Vacina contra a Peste/imunologia , Proteínas Citotóxicas Formadoras de Poros/imunologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/administração & dosagem , Antígenos de Bactérias/toxicidade , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/toxicidade , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Feminino , Granuloma/induzido quimicamente , Granuloma/imunologia , Granuloma/patologia , Imunidade Celular/efeitos dos fármacos , Imunoglobulina E/sangue , Reação no Local da Injeção/imunologia , Reação no Local da Injeção/patologia , Injeções Intramusculares , Interferon gama/sangue , Interleucina-2/sangue , Macaca fascicularis , Masculino , Vacina contra a Peste/administração & dosagem , Vacina contra a Peste/toxicidade , Proteínas Citotóxicas Formadoras de Poros/administração & dosagem , Proteínas Citotóxicas Formadoras de Poros/toxicidade , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/imunologia
11.
Biochem Biophys Res Commun ; 487(4): 834-839, 2017 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-28455229

RESUMO

Thoracic ossification of the ligamentum flavum (TOLF) is a unique disease with ectopic ossification, and is a major cause of thoracic spinal stenosis and myelopathy. However, the underlying etiology remains largely unknown. In this study, the ligamentum flavum was systematically analyzed in TOLF patients by using comprehensive iTRAQ labeled quantitative proteomics. Among 1285 detected proteins, there were 282 proteins identified to be differentially expressed. The Gene Ontology (GO) analysis regarding functional annotation of proteins consists of the following three aspects: the biological process, the molecular function, and the cellular components. The function clustering analysis revealed that ten of the above proteins are related to inflammation, such as tumor necrosis factor (TNF). This finding was subsequently validated by ELISA, which indicated that serum TNF-α of TOLF patients was significantly higher compared with the control group. To address the effect of TNF-α on ossification-related gene expression, we purified and cultured primary cells from thoracic ligamentum flavum of patients with TOLF. TNF-α was then used to stimulate cells. RNA was isolated and analyzed by RT-PCR. Our results showed that TNF-α was able to induce the expressions of osteoblast-specific transcription factor Osterix (Osx) in ligamentum flavum cells, suggesting that it can promote osteoblast differentiation. In addition, as the Osx downstream osteoblast genes OCN and ALP were also activated by TNF-α. This is the first proteomic study to identify inflammation factors such as TNF-α involved in ossified ligamentum flavum in TOLF, which may contribute to a better understanding of the cause of TOLF.


Assuntos
Ligamento Amarelo/metabolismo , Ossificação Heterotópica/metabolismo , Proteômica , Fator de Necrose Tumoral alfa/metabolismo , Humanos , Ligamento Amarelo/efeitos dos fármacos , Ligamento Amarelo/patologia , Ossificação Heterotópica/genética , Ossificação Heterotópica/patologia , Fator de Transcrição Sp7 , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/farmacologia
12.
J Mol Cell Cardiol ; 82: 22-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25739000

RESUMO

Calcium-activated chloride channels (CaCCs) have been implicated in hypertension; however, the mechanism underlying their involvement is unknown. The aim of this study was to determine whether the CaCC ANO1 is involved in the pathogenesis of spontaneous hypertension. Arterial ANO1 expression and the effects on blood pressure (BP) of inhibiting ANO1 with an ANO1 inhibitor, T16(Ainh)-A01, and in vivo RNAi, were examined in spontaneously hypertensive rats (SHRs). Knockdown of ANO1 by siRNA prevented hypertensive development, and attenuation of ANO1 channel activity reduced BP in SHRs. Angiotensin II upregulated ANO1 expression in primary cultures of vascular smooth muscle cells (VSMCs). The protein level and activity of cellular ANO1 positively correlated with VSMC proliferation. Our data indicate an important role of increased ANO1 expression and activity in inducing hypertension in SHRs. It may mediate angiotensin II-dependent vascular remodeling. Our results increase the mechanistic understanding of hypertension and suggest ANO1 as a possible therapeutic target for hypertension.


Assuntos
Canais de Cloreto/genética , Expressão Gênica , Ratos Endogâmicos SHR/genética , Angiotensina II/farmacologia , Animais , Anoctamina-1 , Artérias/efeitos dos fármacos , Artérias/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Proliferação de Células , Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/metabolismo , Modelos Animais de Doenças , Acoplamento Excitação-Contração/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glicosilação , Masculino , Modelos Biológicos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Ratos , Ratos Endogâmicos SHR/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
J Org Chem ; 80(5): 2724-32, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25642974

RESUMO

Surface-modified titanium dioxides by highly dispersed NiO particles have an extended absorption in the visible light region and a reduced hole-electron pair recombination than unmodified TiO2. They have now been successfully applied as highly active heterogeneous photocatalysts in the visible light mediated direct cyclization of tertiary anilines with maleimides to give tetrahydroquinoline products in moderate to high yields at ambient temperature. In contrast with unmodified titanium dioxide catalysts that are conventionally used in a stoichiometric amount in combination with UVA light, only a catalytic amount (1 mol %) of the surface-modified TiO2 catalyst is needed along with visible light to efficiently catalyze the reaction. Compared with transition-metal complexes such as Ru(bpy)3Cl2 or Ir(ppy)2(dtbbpy)PF6, advantages of these surface-modified titanium dioxides as photocatalyst include high catalytic activity, low cost, ease of recovering, and being able to be used for at least nine times without significant decay of catalytic activity.


Assuntos
Compostos de Anilina/síntese química , Maleimidas/síntese química , Níquel/química , Titânio/química , Compostos de Anilina/química , Catálise , Ciclização , Luz , Maleimidas/química , Fotoquímica
14.
J Sep Sci ; 38(2): 332-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25385150

RESUMO

In this study, diamino moiety functionalized silica nanoparticles with the size of 118 ± 12 nm were successfully synthesized and directly introduced into a chiral capillary electrophoresis system to improve the enantioseparation of 9-fluorenyl methoxycarbonyl derivatized amino acids using norvancomycin as chiral selector. Under acidic background electrolyte conditions, functional silica nanoparticles can be readily adsorbed onto the inner surface of bare silica capillary column through electrostatic interaction to form a dynamic coating, resulting in a reversed anodic electro-osmotic flow (i.e. from cathode to anode). As expected, chiral amino acid derivatives (usually negatively charged) can be rapidly separated under co-electro-osmotic flow conditions in the current separation system. Furthermore, the column performance and detection sensitivity for the enantioseparation were also obviously improved because the adsorption of chiral selector of norvancomycin to the capillary wall was greatly suppressed. Some important factors influencing the separation, such as the coating thickness, background electrolyte concentration, functional silica nanoparticles concentration, and the organic modifier were also investigated and the optimized separation conditions were obtained.


Assuntos
Aminoácidos/isolamento & purificação , Eletroforese Capilar/métodos , Nanopartículas/química , Dióxido de Silício/química , Adsorção , Aminoácidos/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Estereoisomerismo
15.
J Nanosci Nanotechnol ; 15(1): 138-43, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328318

RESUMO

Biosafety assessment of nanoparticles has been of great interest in the development of nanoscience and nanotechnology. Here, the water-soluble hyperbranched polyester nanoparticles with carboxylic acid functional group (HBPE-CA NPs) are synthesized and characterized. They have amphiphilic structure that include hydrophobic hyperbranched polyester (HBPE) core and hydrophilic carboxylated terminal groups. Biosafety assessment tests of the HBPE-CA NPs include coagulation times, hemolysis, complement activation, platelet activation and cytotoxicity (MTT) are performed. The results show that the HBPE-CA NPs exhibit good hemocompatibility that strongly depend on the amphiphilic structure. Moreover, the results also indicate the non-cytotoxicity of the HBPE-CA NPs. So the HBPE-CA NPs provide a promising platform of blood circulation system for illness therapy with the help of the drug-loaded capacity of-HBPE.


Assuntos
Materiais Biocompatíveis/química , Ácidos Carboxílicos/química , Nanopartículas/química , Ativação Plaquetária/efeitos dos fármacos , Poliésteres/química , Animais , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Hemólise/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Coelhos
16.
J Org Chem ; 79(16): 7572-82, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25057755

RESUMO

A new photoinduced three-component reaction between a cyanoarene, an alkene and an N-protected pyrrole has been developed. This reaction extended the scope of the photo-NOCAS reaction by introducing pyrrole as a neutral carbon-centered nucleophile. The cyanoarenes used include tetracyanobenzene (TCB), 2,3,5,6-tetrafluoro-1,4-dicyanobenzene (TFDCB) and 1,4-dicyanobenzene (DCB). N-Methyl, N-phenyl and N-Boc pyrroles are suitable nucleophiles in the reaction. Taking advantage of the strong electron acceptor ability of the singlet excited TCB, a wide range of alkenes, including the highly electron deficient 4-fluoro-, 4-chloro-, 2,3,4,5,6-pentafluorostyrenes and N-methylmaleimide take part in this reaction, leading to the simultaneous 1,2-diarylation of the alkene and the regioselective 2-alkylation of the pyrrole ring via sequential formation of two new C-C bonds between the three reactants.

17.
Z Naturforsch C J Biosci ; 69(7-8): 283-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25265848

RESUMO

A series of annulated 7-membered oxazepine and 8-membered oxazocine derivatives were synthesized by photoreaction of phthalimide derivatives and an alkene. The antimicrobial activities of the synthesized compounds were evaluated, and compounds 18 and 20 exhibited best antibacterial activity against Gram-positive bacteria. The relationships between structure (especially steric structure) and antimicrobial activities are discussed.


Assuntos
Oxazepinas/síntese química , Oxazepinas/farmacologia , Oxazocinas/síntese química , Oxazocinas/farmacologia , Antibacterianos/síntese química , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Modelos Moleculares , Relação Estrutura-Atividade , Difração de Raios X
18.
Mod Rheumatol ; 24(5): 709-14, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24251996

RESUMO

Over the past years, several evidences have supported an important role of specific micronutrients, including vitamin A, vitamin D and vitamin E in immune dysfunction, vascular involvement and fibrotic changes involved in systemic sclerosis (SSc) development. In PubMed, eight clinical trials about the therapy of micronutrients on SSc patients were searched out using medical subject headings terms (SSc: "scleroderma, localized", "scleroderma, systemic", "scleroderma, diffuse" and "scleroderma, limited"; vitamins "vitamin A", "thiamin", "riboflavin", "niacin", "pantothenic acid", "vitamin B 6", "biotin", "folic acid", "vitamin B 12", "inositol", "choline", "ascorbic acid", "vitamin D", "vitamin E", "tocopherols", "vitamin K" and "vitamin P"; and minerals: "calcium", "magnesium", "potassium", "sodium", "phosphorus", "sulfur", "chlorine", "iron", "copper", "iodine", "zinc", "selenium", "manganese", "molybdenum", "cobalt", "chromium", "tin", "vanadium", "silicon", "nickel" and "fluorine"). This brief review will summarize current understanding on that for the further prospect of future studies. Though the clinical trials for the treatment of SSc with micronutrients are still in their infancy, more researches are needed to substantiate the current results and accelerate the knowledge in this field.


Assuntos
Micronutrientes/uso terapêutico , Escleroderma Sistêmico/tratamento farmacológico , Humanos , Resultado do Tratamento
19.
Wei Sheng Wu Xue Bao ; 54(11): 1362-8, 2014 Nov 04.
Artigo em Chinês | MEDLINE | ID: mdl-25752143

RESUMO

OBJECTIVE: To investigate the polymorphism of clustered regularly interspaced short palindromic repeats (CRISPR) in Bacillu santhracis and the application to molecular typing based on the polymorphism of CRISPR in B. anthracis. METHODS: We downloaded the whole genome sequence of 6 B. anthracis strains and extracted the CRISPR sites. We designed the primers of CRISPR sites and amplified the CRISPR fragments in 193 B. anthracis strains by PCR and sequenced these fragments. In order to reveal the polymorphism of CRISPR in B. anthracis, wealigned all the extracted sequences and sequenced results by local blasting. At the same time, we also analyzed the CRISPR sites in B. cereus and B. thuringiensis. RESULTS: We did not find any polymorphism of CRISPR in B. anthracis. CONCLUSION: The molecular typing approach based on CRISPR polymorphism is not suitable for B. anthracis, but it is possible for us to distinguish B. anthracis from B. cereus and B. thuringiensis.


Assuntos
Bacillus anthracis/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Bacillus anthracis/classificação , Sequência de Bases , Genoma Bacteriano , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético
20.
J Affect Disord ; 347: 327-334, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-37992777

RESUMO

BACKGROUND: Depressed mood affects a significant number of patients with cancer, and can impair their quality of life and interfere with successful treatment. Our study aims to create a predictive model for identifying high-risk groups of depressed mood in cancer patients, offering a theoretical support for preventing depressed mood in these individuals. METHODS: The China Health and Retirement Longitudinal Study (CHARLS) provided the data for this research, which used CES-D as a tool to identify individuals with depressed mood. Influencing factors of depressed mood in cancer patients was analyzed using a binary logistic regression model. Using the Harvard Cancer Index, we classified the high-risk patients for depressed mood. RESULTS: In present study, 52.96 % of cancer patients met criteria for depressed mood based on the CES-D. Significant correlations were found between depressed mood and factors such as gender, self-rated health, sleep duration, exercise, satisfaction with family, residence, education, life satisfaction, and medical insurance. Utilizing the Harvard Cancer Index, we classified patients into five risk levels for depressed mood, revealing a significant variation in the number of depressive patients across these levels (x2=99.82, P < 0.05). Notably, the incidence of depressed mood increased with the risk level among cancer patients (x2=103.40, P < 0.05). LIMITATIONS: Lack of data on tumor typing and subgroups makes it unlikely to explore the specifics of depressed mood in patients with various types of cancer. CONCLUSION: The determinants of depressed mood in cancer patients are multi-dimensional. The Harvard Cancer Index may be helpful in identifying high-risk populations.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Estudos Longitudinais , Fatores de Risco , Escolaridade , Neoplasias/epidemiologia , Depressão/epidemiologia
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