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1.
Anal Biochem ; 690: 115512, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38527608

RESUMO

A self-signal electrochemical identification interface was prepared for the determination of circulating tumor DNA (ctDNA) in peripheral blood based on poly-xanthurenic acid (PXTA) assembled on black phosphorus nanosheets (BPNSs) acquired through simple ultrasonication method. The BPNSs with large surface area could be integrated with the xanthurenic acid (XTA) monomers by right of physisorption, and hence improved the electropolymerization efficiency and was beneficial to the enlargement of the signal response of PXTA. The assembled PXTA/BPNSs composite with attractive electrochemical activity was adopted as a platform for the recognition of DNA immobilization and hybridization. The probe ssDNA was covalently fixed onto the PXTA/BPNSs composite with plentiful carboxyl groups through the terminate free amines of DNA probes by use of the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydrosulfosuccinimide cross-linking reaction, accompanied with the decline of the self-signal response. When the hybridization between the probe ssDNA and the target DNA was accomplished, the self-signal response of the composite interface reproduced by virtue of the shaping of helix construction. The determination limit of the assembled DNA identification interface was 2.1 × 10-19 mol/L, and the complementary target DNA concentrations varied from 1.0 × 10-18 mol/L to 1.0 × 10-12 mol/L. The DNA identification platform displayed magnificent sensitivity, specificity and stability, and was efficaciously implemented to the mensuration of ctDNA derived from colorectal cancer.

2.
Angew Chem Int Ed Engl ; 62(52): e202314832, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37946607

RESUMO

The Stille cross-coupling reaction is one of the most common strategies for the construction of C-C bonds. Despite notable strides in the advancement of the Stille reaction, persistent challenges persist in hindering its greener evolution. These challenges encompass multiple facets, such as the high cost of precious metals and ligands, the demand for various additives, and the slow reaction rate. In comparison to the dominant palladium-catalysed Stille reactions, cost-effective nickel-catalysed systems lag behind, and enantioconvergent Stille reactions of racemic stannanes remain undeveloped. Herein, we present a pioneering instance of nickel-catalysed enantioconvergent Stille cross-coupling reactions of racemic stannane reagents, resulting in the formation of C-C bonds in good to high yields with excellent stereoselectivity. This strategy provides a practical, scalable, and operationally straightforward method for the synthesis of C(sp3 )-C(sp3 ), C(sp3 )-C(sp2 ), and C(sp3 )-C(sp) bonds under exceptionally mild conditions (without additives and bases, ambient temperature). The innovative use of synergistic photoredox/nickel catalysis enables a novel single-electron transmetalation process of stannane reagents, providing a new research paradigm of Stille reactions.

3.
Chem Sci ; 14(44): 12676-12683, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38020394

RESUMO

An unprecedented nickel-catalysed enantioselective hydromonofluoromethylation of 1,3-enynes is developed, allowing the diverse access to monofluoromethyl-tethered axially chiral allenes, including the challenging deuterated monofluoromethyl (CD2F)-tethered ones that are otherwise inaccessible. It represents the first asymmetric 1,4-hydrofunctionalization of 1,3-enynes using low-cost asymmetric nickel catalysis, thus opening a new avenue for the activation of 1,3-enynes in reaction development. The utility is further verified by its broad substrate scope, good functionality tolerance, mild conditions, and diversified product elaborations toward other valuable fluorinated structures. Mechanistic experiments and DFT calculations provide insights into the reaction mechanism and the origin of the enantioselectivity.

4.
Diabetes Care ; 46(5): 1014-1018, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36867433

RESUMO

OBJECTIVE: To examine whether iron intake and genetically determined iron overload interact in predisposing to the development of childhood islet autoimmunity (IA) and type 1 diabetes (T1D). RESEARCH DESIGN AND METHODS: In The Environmental Determinants of Diabetes in the Young (TEDDY) study, 7,770 genetically high-risk children were followed from birth until the development of IA and progression to T1D. Exposures included energy-adjusted iron intake in the first 3 years of life and a genetic risk score (GRS) for increased circulating iron. RESULTS: We found a U-shaped association between iron intake and risk of GAD antibody as the first autoantibody. In children with GRS ≥2 iron risk alleles, high iron intake was associated with an increased risk of IA, with insulin as first autoantibody (adjusted hazard ratio 1.71 [95% CI 1.14; 2.58]) compared with moderate iron intake. CONCLUSIONS: Iron intake may alter the risk of IA in children with high-risk HLA haplogenotypes.


Assuntos
Diabetes Mellitus Tipo 1 , Sobrecarga de Ferro , Ilhotas Pancreáticas , Criança , Humanos , Lactente , Autoimunidade/genética , Ferro da Dieta , Ferro , Fatores de Risco , Autoanticorpos/genética , Sobrecarga de Ferro/genética , Predisposição Genética para Doença
5.
Bioelectrochemistry ; 148: 108231, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36166896

RESUMO

A self-signal electrochemical sensing platform was constructed for direct recognition of circulating tumor DNA (ctDNA) employing black phosphorous nanosheets (BPNS) assembled with flavin adenine dinucleotide (FAD) prepared by ultrasonication approach. FAD provided a highly efficient and stable dispersing medium for acquiring highly dispersed BPNS in aqueous phase. The obtained FAD/BPNS nanocomposite exhibited favorable electrochemical redox activity and was utilized as the interface for the immobilization and hybridization of DNA. The amine-terminated probe ssDNA was covalently assembled onto the FAD/BPNS nanocomposite with plentiful phosphonate groups accompanied by the decrease of the self-signal. The self-redox signal of the nanointerface regenerated after the probe hybridized with the complementary sequence as a result of DNA transformation. Electrochemical response enhanced with complementary DNA concentration from 1.0 × 10-18 to 1.0 × 10-8 mol/L with a detection limit of 2.6 × 10-19 mol/L. The DNA determination platform revealed outstanding sensitivity, specificity and stableness, and was successfully employed in the detection of ctDNA associated with colorectal cancer. The developed biosensing strategy is simple to accomplish and has the potency for the application for diverse morbific gene without sophisticated label procedure.


Assuntos
Técnicas Biossensoriais , DNA Tumoral Circulante , Organofosfonatos , Aminas , Técnicas Biossensoriais/métodos , DNA/genética , DNA Complementar , Técnicas Eletroquímicas/métodos , Flavina-Adenina Dinucleotídeo , Fósforo
6.
Laryngoscope Investig Otolaryngol ; 7(4): 970-981, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36000042

RESUMO

Objective: The CO2 laser and 532 nm potassium titanyl phosphate (KTP) laser have been applied to treat recurrent respiratory papillomatosis (RRP). This systematic review sought to compare outcome differences between these two methods. Data Sources: Embase, Web of Science, PubMed, and the Cochrane Library. Review Methods: CO2 laser and KTP laser studies were obtained by keyword searches of four authoritative medical databases. Articles were screened and retained when conforming to inclusion criteria. The primary outcome was cure rate; the secondary outcomes were recurrence, death, remission, clearance, and human papillomavirus (HPV)-detected rates, as well as laser effectiveness rates. Postoperative complications rate was the safety outcome measure. All outcomes were summarized within the CO2 and KTP groups, with results statistically compared (p < .05). Results: Overall, the cure rates were 87.25% (KTP group) and 75.98% (CO2 group; p < .05). Complication rates significantly differed between the KTP (2.32%) and CO2 (17.71%) groups (p < .0001). There was a relatively higher but not significant difference in the recurrence rates between the CO2 (18.6%) and KTP (10.87%) groups (p = .1595). The CO2 group remission rate was considerably lower (38.9%) than the KTP group (88.46%, p < .0001). HPV-detected and clearance rates were only reported for the CO2 group. The bias risks were 13.1 ± 1.45 (CO2) and 13.6 ± 1.52 (KTP) for the two groups, indicating evidence was of fair quality. Conclusion: Overall, KTP laser excision showed significantly better postoperative clinical outcomes than the CO2 laser, with a lower failure rate. Available fair-quality evidence suggests KTP laser excision might be better for treating RRP. Nevertheless, more high-quality randomized controlled studies are needed to compare these two surgical techniques, particularly in terms of reporting functional data such as vocal outcomes.

7.
Exp Mol Med ; 54(5): 626-638, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35562586

RESUMO

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by inappropriate hyperglycemia, which causes endothelial dysfunction and peripheral neuropathy, ultimately leading to multiple complications. One prevalent complication is diabetic erectile dysfunction (ED), which is more severe and more resistant to treatment than nondiabetic ED. The serum glycoprotein leucine-rich ɑ-2-glycoprotein 1 (LRG1) is a modulator of TGF-ß-mediated angiogenesis and has been proposed as a biomarker for a variety of diseases, including DM. Here, we found that the adhesion GPCR latrophilin-2 (LPHN2) is a TGF-ß-independent receptor of LRG1. By interacting with LPHN2, LRG1 promotes both angiogenic and neurotrophic processes in mouse tissue explants under hyperglycemic conditions. Preclinical studies in a diabetic ED mouse model showed that LRG1 administration into the penile tissue, which exhibits significantly increased LPHN2 expression, fully restores erectile function by rescuing vascular and neurological abnormalities. Further investigations revealed that PI3K, AKT, and NF-κB p65 constitute the key intracellular signaling pathway of the LRG1/LPHN2 axis, providing important mechanistic insights into LRG1-mediated angiogenesis and nerve regeneration in DM. Our findings suggest that LRG1 can be a potential new therapeutic option for treating aberrant peripheral blood vessels and neuropathy associated with diabetic complications, such as diabetic ED.


Assuntos
Diabetes Mellitus , Disfunção Erétil , Animais , Disfunção Erétil/etiologia , Glicoproteínas/metabolismo , Humanos , Masculino , Camundongos , Neovascularização Patológica , Receptores de Peptídeos , Receptores de Fatores de Crescimento Transformadores beta , Fator de Crescimento Transformador beta/metabolismo
8.
Sci Adv ; 7(43): eabh3794, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34669463

RESUMO

Cancer therapies are being considered for treating rare noncancerous diseases like pulmonary hypertension (PH), but effective computational screening is lacking. Via transcriptomic differential dependency analyses leveraging parallels between cancer and PH, we mapped a landscape of cancer drug functions dependent upon rewiring of PH gene clusters. Bromodomain and extra-terminal motif (BET) protein inhibitors were predicted to rely upon several gene clusters inclusive of galectin-8 (LGALS8). Correspondingly, LGALS8 was found to mediate the BET inhibitor­dependent control of endothelial apoptosis, an essential role for PH in vivo. Separately, a piperlongumine analog's actions were predicted to depend upon the iron-sulfur biogenesis gene ISCU. Correspondingly, the analog was found to inhibit ISCU glutathionylation, rescuing oxidative metabolism, decreasing endothelial apoptosis, and improving PH. Thus, we identified crucial drug-gene axes central to endothelial dysfunction and therapeutic priorities for PH. These results establish a wide-ranging, network dependency platform to redefine cancer drugs for use in noncancerous conditions.

9.
Circ Res ; 127(5): 677-692, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32493166

RESUMO

RATIONALE: Unproven theories abound regarding the long-range uptake and endocrine activity of extracellular blood-borne microRNAs into tissue. In pulmonary hypertension (PH), microRNA-210 (miR-210) in pulmonary endothelial cells promotes disease, but its activity as an extracellular molecule is incompletely defined. OBJECTIVE: We investigated whether chronic and endogenous endocrine delivery of extracellular miR-210 to pulmonary vascular endothelial cells promotes PH. METHODS AND RESULTS: Using miR-210 replete (wild-type [WT]) and knockout mice, we tracked blood-borne miR-210 using bone marrow transplantation and parabiosis (conjoining of circulatory systems). With bone marrow transplantation, circulating miR-210 was derived predominantly from bone marrow. Via parabiosis during chronic hypoxia to induce miR-210 production and PH, miR-210 was undetectable in knockout-knockout mice pairs. However, in plasma and lung endothelium, but not smooth muscle or adventitia, miR-210 was observed in knockout mice of WT-knockout pairs. This was accompanied by downregulation of miR-210 targets ISCU (iron-sulfur assembly proteins)1/2 and COX10 (cytochrome c oxidase assembly protein-10), indicating endothelial import of functional miR-210. Via hemodynamic and histological indices, knockout-knockout pairs were protected from PH, whereas knockout mice in WT-knockout pairs developed PH. In particular, pulmonary vascular engraftment of miR-210-positive interstitial lung macrophages was observed in knockout mice of WT-knockout pairs. To address whether engrafted miR-210-positive myeloid or lymphoid cells contribute to paracrine miR-210 delivery, we studied miR-210 knockout mice parabiosed with miR-210 WT; Cx3cr1 knockout mice (deficient in myeloid recruitment) or miR-210 WT; Rag1 knockout mice (deficient in lymphocytes). In both pairs, miR-210 knockout mice still displayed miR-210 delivery and PH, thus demonstrating a pathogenic endocrine delivery of extracellular miR-210. CONCLUSIONS: Endogenous blood-borne transport of miR-210 into pulmonary vascular endothelial cells promotes PH, offering fundamental insight into the systemic physiology of microRNA activity. These results also describe a platform for RNA-mediated crosstalk in PH, providing an impetus for developing blood-based miR-210 technologies for diagnosis and therapy in this disease.


Assuntos
Endotélio Vascular/metabolismo , Hipertensão Pulmonar/metabolismo , Pulmão/irrigação sanguínea , MicroRNAs/metabolismo , Animais , Transplante de Medula Óssea , Receptor 1 de Quimiocina CX3C/genética , Receptor 1 de Quimiocina CX3C/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/fisiopatologia , Hipóxia/complicações , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/sangue , MicroRNAs/genética , Parabiose , Transdução de Sinais
10.
Mol Ther ; 28(1): 142-156, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31606324

RESUMO

Hypoxic microenvironments exist in developing embryonic tissues and determine stem cell fate. We previously demonstrated that hypoxic priming plays roles in lineage commitment of embryonic stem cells. In the present study, we found that hypoxia-primed embryoid bodies (Hyp-EBs) efficiently differentiate into the myogenic lineage, resulting in the induction of the myogenic marker MyoD, which was not mediated by hypoxia-inducible factor 1α (HIF1α) or HIF2α, but rather by Sp1 induction and binding to the MyoD promoter. Knockdown of Sp1 in Hyp-EBs abrogated hypoxia-induced MyoD expression and myogenic differentiation. Importantly, in the cardiotoxin-muscle injury mice model, Hyp-EB transplantation facilitated muscle regeneration in vivo, whereas transplantation of Sp1-knockdown Hyp-EBs failed to do. Moreover, we compared microRNA (miRNA) expression profiles between EBs under normoxia versus hypoxia and found that hypoxia-mediated Sp1 induction was mediated by the suppression of miRNA-92a, which directly targeted the 3' untranslated region (3' UTR) of Sp1. Further, the inhibitory effect of miRNA-92a on Sp1 in luciferase assay was abolished by a point mutation in specific sequence in the Sp1 3' UTR that is required for the binding of miRNA-92a. Collectively, these results suggest that hypoxic priming enhances EB commitment to the myogenic lineage through miR-92a/Sp1/MyoD regulatory axis, suggesting a new pathway that promotes myogenic-lineage differentiation.


Assuntos
Diferenciação Celular/genética , Hipóxia Celular/genética , Linhagem da Célula/genética , MicroRNAs/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Desenvolvimento Muscular/genética , Proteína MyoD/metabolismo , Fator de Transcrição Sp1/metabolismo , Regiões 3' não Traduzidas , Animais , Células Cultivadas , Técnicas de Silenciamento de Genes , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/genética , Transfecção
11.
Eur Heart J ; 41(2): 239-252, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31419281

RESUMO

AIMS: Proprotein convertase subtilisin/kexin type-9 (PCSK9), a molecular determinant of low-density lipoprotein (LDL) receptor (LDLR) fate, has emerged as a promising therapeutic target for atherosclerotic cardiovascular diseases. However, the precise mechanism by which PCSK9 regulates the internalization and lysosomal degradation of LDLR is unknown. Recently, we identified adenylyl cyclase-associated protein 1 (CAP1) as a receptor for human resistin whose globular C-terminus is structurally similar to the C-terminal cysteine-rich domain (CRD) of PCSK9. Herein, we investigated the role of CAP1 in PCSK9-mediated lysosomal degradation of LDLR and plasma LDL cholesterol (LDL-C) levels. METHODS AND RESULTS: The direct binding between PCSK9 and CAP1 was confirmed by immunoprecipitation assay, far-western blot, biomolecular fluorescence complementation, and surface plasmon resonance assay. Fine mapping revealed that the CRD of PCSK9 binds with the Src homology 3 binding domain (SH3BD) of CAP1. Two loss-of-function polymorphisms found in human PCSK9 (S668R and G670E in CRD) were attributed to a defective interaction with CAP1. siRNA against CAP1 reduced the PCSK9-mediated degradation of LDLR in vitro. We generated CAP1 knock-out mice and found that the viable heterozygous CAP1 knock-out mice had higher protein levels of LDLR and lower LDL-C levels in the liver and plasma, respectively, than the control mice. Mechanistic analysis revealed that PCSK9-induced endocytosis and lysosomal degradation of LDLR were mediated by caveolin but not by clathrin, and they were dependent on binding between CAP1 and caveolin-1. CONCLUSION: We identified CAP1 as a new binding partner of PCSK9 and a key mediator of caveolae-dependent endocytosis and lysosomal degradation of LDLR.


Assuntos
Aterosclerose/genética , Proteínas de Transporte/genética , LDL-Colesterol/sangue , Mutação , Pró-Proteína Convertase 9/genética , Receptores de LDL/sangue , Animais , Aterosclerose/metabolismo , Proteínas de Transporte/metabolismo , DNA/genética , Análise Mutacional de DNA , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Knockout , Pró-Proteína Convertase 9/metabolismo
12.
JAMA ; 322(6): 514-523, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408136

RESUMO

Importance: High gluten intake during childhood may confer risk of celiac disease. Objectives: To investigate if the amount of gluten intake is associated with celiac disease autoimmunity and celiac disease in genetically at-risk children. Design, Setting, and Participants: The participants in The Environmental Determinants of Diabetes in the Young (TEDDY), a prospective observational birth cohort study designed to identify environmental triggers of type 1 diabetes and celiac disease, were followed up at 6 clinical centers in Finland, Germany, Sweden, and the United States. Between 2004 and 2010, 8676 newborns carrying HLA antigen genotypes associated with type 1 diabetes and celiac disease were enrolled. Screening for celiac disease with tissue transglutaminase autoantibodies was performed annually in 6757 children from the age of 2 years. Data on gluten intake were available in 6605 children (98%) by September 30, 2017. Exposures: Gluten intake was estimated from 3-day food records collected at ages 6, 9, and 12 months and biannually thereafter until the age of 5 years. Main Outcomes and Measures: The primary outcome was celiac disease autoimmunity, defined as positive tissue transglutaminase autoantibodies found in 2 consecutive serum samples. The secondary outcome was celiac disease confirmed by intestinal biopsy or persistently high tissue transglutaminase autoantibody levels. Results: Of the 6605 children (49% females; median follow-up: 9.0 years [interquartile range, 8.0-10.0 years]), 1216 (18%) developed celiac disease autoimmunity and 447 (7%) developed celiac disease. The incidence for both outcomes peaked at the age of 2 to 3 years. Daily gluten intake was associated with higher risk of celiac disease autoimmunity for every 1-g/d increase in gluten consumption (hazard ratio [HR], 1.30 [95% CI, 1.22-1.38]; absolute risk by the age of 3 years if the reference amount of gluten was consumed, 28.1%; absolute risk if gluten intake was 1-g/d higher than the reference amount, 34.2%; absolute risk difference, 6.1% [95% CI, 4.5%-7.7%]). Daily gluten intake was associated with higher risk of celiac disease for every 1-g/d increase in gluten consumption (HR, 1.50 [95% CI, 1.35-1.66]; absolute risk by age of 3 years if the reference amount of gluten was consumed, 20.7%; absolute risk if gluten intake was 1-g/d higher than the reference amount, 27.9%; absolute risk difference, 7.2% [95% CI, 6.1%-8.3%]). Conclusions and Relevance: Higher gluten intake during the first 5 years of life was associated with increased risk of celiac disease autoimmunity and celiac disease among genetically predisposed children.


Assuntos
Autoanticorpos/sangue , Doença Celíaca/etiologia , Proteínas Alimentares/efeitos adversos , Predisposição Genética para Doença , Glutens/efeitos adversos , Transglutaminases/imunologia , Autoimunidade , Doença Celíaca/epidemiologia , Doença Celíaca/genética , Doença Celíaca/imunologia , Pré-Escolar , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/genética , Registros de Dieta , Feminino , Glutens/administração & dosagem , Humanos , Incidência , Lactente , Masculino , Estudos Prospectivos , Risco
13.
J Am Chem Soc ; 141(17): 6843-6847, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30995028

RESUMO

Converting elemental white phosphorus directly into organophosphorus or polyphosphorus is meaningful, challenging and attractive. The ate-complexes of aluminacyclopentadienes 1a,b react with P4 to afford selectively the cyclotetraphosphanes 2a,b featuring four newly formed P-C bonds and a planar square cyclo-P4 ring. Density functional theory calculations show that the conversion of tetrahedral P4 to planar cyclo-P4 moiety undergoes through an unexpected 1,1- P-insertion/Diels-Alder reaction/isomerization cascade process. The reaction of 2a with iodomethane or p-benzoquinone afforded the P-methylation product 3 and the metal-free cyclotetraphosphane 4, respectively. Interestingly, reduction of 4 generated the phospholyl anions 5 and 6 while treatment of 4 with iodomethane afforded the phospholyl cation 7.

14.
RSC Adv ; 9(17): 9613-9619, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35520724

RESUMO

In this work, a novel self-signal DNA electrochemical biosensor was constructed based on tungsten disulfide (WS2) nanosheets combined with poly(indole-6-carboxylic acid) (PIn6COOH) as the sensing interface. The WS2 nanosheets were synthesized via a simple solvent exfoliation method from bulk WS2, and then PIn6COOH was electropolymerized on the WS2 nanosheet-modified carbon paste electrode to obtain a unique nanocomposite. The electropolymerization efficiency was remarkably improved, ascribed to the physical adsorption between WS2 nanosheets and aromatic In6COOH monomers, resulting in an increase of the electrochemical response of PIn6COOH. Owing to the presence of π-π interactions between the conjugated PIn6COOH/WS2 nanocomposite and DNA bases, the probe ssDNA was noncovalently assembled on the nanocomposite substrate. After the hybridization of the probe ssDNA with the target DNA, the formation of the double-helix structure induced the resulting dsDNA to be released from the surface of the conjugated nanocomposite, accompanied with the self-signal regeneration of the nanocomposite ("signal-on"). The constructed PIn6COOH/WS2 nanocomposite was not only employed as an interface for DNA immobilization but also reflected the signal transduction stemming from DNA immobilization and hybridization without any external indicators or complex labeling processes. A detection limit of 2.3 × 10-18 mol L-1 has been estimated and a dynamic range of 1.0 × 10-17 mol L-1 to 1.0 × 10-11 mol L-1 has been shown for the detection of a PIK3CA gene related to lung cancer. Selectivity of the biosensor has been researched in the presence of noncomplementary and base mismatched DNA sequences.

15.
Biosens Bioelectron ; 105: 116-120, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29367008

RESUMO

A high-performance sensing platform based on poly-xanthurenic acid (PXA) film functionalized MoS2 nanosheets was developed for electrochemical detection of circulating tumor DNA in peripheral blood. The MoS2 nanosheets were obtained using a simple ultrasonic method from bulk MoS2. The physical adsorption between MoS2 and aromatic XA monomers effectively improved the electropolymerization efficiency, accompanied with an increased electrochemical response of PXA. The obtained PXA/MoS2 nanocomposite not only served as a substrate for DNA immobilization but also reflected the electrochemical transduction originating from DNA immobilization and hybridization without any complex labelling processes or outer indicators. The immobilization of the probe ssDNA was achieved via noncovalent assembly due to the π-π interaction between PXA and DNA bases. After the hybridization of the probe ssDNA with the target DNA, the formation of helix structure induced the resulted dsDNA to be released from the surface of the PXA/MoS2 nanocomposite. The detection limit of this constructed DNA biosensor was calculated in the linear target DNA concentrations range from 1.0 × 10-16 mol/L to 1.0 × 10-10 mol/L and it was found to be 1.8 × 10-17 mol/L.


Assuntos
Técnicas Biossensoriais/métodos , DNA Tumoral Circulante/sangue , Dissulfetos/química , Ácidos Nucleicos Imobilizados/química , Molibdênio/química , Nanoestruturas/química , Xanturenatos/química , Técnicas Eletroquímicas/métodos , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico
16.
RSC Adv ; 8(69): 39703-39709, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-35558023

RESUMO

Tungsten disulfide (WS2) nanosheets supported poly(xanthurenic acid) (PXa) was used as the signal transduction interface for electrochemical genosensing. The WS2 nanosheets were obtained from bulk WS2 using a simple ultrasonic method. Due to the unique physical adsorption of Xa monomers to WS2, the electropolymerization efficiency was greatly improved, accompanied with an increased electrochemical response of PXa. The obtained PXa/WS2 nanocomposite not only served as a substrate for DNA immobilization but also reflected the electrochemical transduction originating from DNA immobilization and hybridization without any other indicators or complicated labelling steps. Owing to the presence of abundant carboxyl groups, the probe ssDNA was covalently attached on the carboxyl-terminated PXa/WS2 nanocomposite through the free amines of DNA sequences based on the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydrosulfosuccinimide crosslinking reaction. The covalently immobilized probe ssDNA could selectively hybridize with its target DNA to form dsDNA on the surface of the PXa/WS2 nanocomposite. This developed biosensor achieved a satisfactory detection limit down to 1.6 × 10-16 mol L-1 and a dynamic range of 1.0 × 10-15 to 1.0 × 10-11 mol L-1 for detection of circulating tumor DNA related to gastric carcinoma. Selectivity of the biosensor has been investigated in presence of non-complementary, one-mismatched and two-mismatched DNA sequences.

17.
Br J Nutr ; 117(3): 466-472, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28249640

RESUMO

Perinatal exposure to nutrients and dietary components may affect the risk for coeliac disease (CD). We investigated the association between maternal use of vitamin D, n-3 fatty acids (FA) and Fe supplements during pregnancy and risk for CD autoimmunity (CDA) and CD in the offspring. Children at increased genetic risk were prospectively followed from birth in The Environmental Determinants of Diabetes in the Young (TEDDY) study. CDA was defined as having persistently positive tissue transglutaminase autoantibodies (tTGA). Diagnosis of CD was either biopsy-confirmed or considered likely if having persistently elevated levels of tTGA>100 AU. Of 6627 enrolled children, 1136 developed CDA at a median 3·1 years of age (range 0·9-10) and 409 developed CD at a median 3·9 years of age (range 1·2-11). Use of supplements containing vitamin D, n-3 FA and Fe was recalled by 66, 17 and 94 % of mothers, respectively, at 3-4 months postpartum. The mean cumulative intake over the entire pregnancy was 2014 µg vitamin D (sd 2045 µg), 111 g n-3 FA (sd 303 g) and 8806 mg Fe (sd 7017 mg). After adjusting for country, child's human leucocyte antigen genotype, sex, family history of CD, any breast-feeding duration and household crowding, Cox's proportional hazard ratios did not suggest a statistically significant association between the intake of vitamin D, n-3 FA or Fe, and risk for CDA or CD. Dietary supplementation during pregnancy may help boost nutrient intake, but it is not likely to modify the risk for the disease in the offspring.


Assuntos
Doença Celíaca , Suplementos Nutricionais , Ácidos Graxos Ômega-3/farmacologia , Ferro/farmacologia , Micronutrientes/farmacologia , Fenômenos Fisiológicos da Nutrição Pré-Natal , Vitamina D/farmacologia , Autoimunidade , Doença Celíaca/etiologia , Criança , Suplementos Nutricionais/efeitos adversos , Feminino , Humanos , Masculino , Gravidez , Modelos de Riscos Proporcionais
18.
Org Biomol Chem ; 14(24): 5516-9, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-26805776

RESUMO

An iron-catalyzed arylation of α-aryl-α-diazoesters with electron-rich benzene rings was developed, which provides an efficient method for the preparation of 1,1-diarylacetates with high yields and excellent chemo- and regio-selectivities.

19.
JAMA Pediatr ; 170(1): 20-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26552054

RESUMO

IMPORTANCE: Probiotics have been hypothesized to affect immunologic responses to environmental exposures by supporting healthy gut microbiota and could therefore theoretically be used to prevent the development of type 1 diabetes mellitus (T1DM)-associated islet autoimmunity. OBJECTIVE: To examine the association between supplemental probiotic use during the first year of life and islet autoimmunity among children at increased genetic risk of T1DM. DESIGN, SETTING, AND PARTICIPANTS: In this ongoing prospective cohort study that started September 1, 2004, children from 6 clinical centers, 3 in the United States (Colorado, Georgia/Florida, and Washington) and 3 in Europe (Finland, Germany, and Sweden), were followed up for T1DM-related autoantibodies. Blood samples were collected every 3 months between 3 and 48 months of age and every 6 months thereafter to determine persistent islet autoimmunity. Details of infant feeding, including probiotic supplementation and infant formula use, were monitored from birth using questionnaires and diaries. We applied time-to-event analysis to study the association between probiotic use and islet autoimmunity, stratifying by country and adjusting for family history of type 1 diabetes, HLA-DR-DQ genotypes, sex, birth order, mode of delivery, exclusive breastfeeding, birth year, child's antibiotic use, and diarrheal history, as well as maternal age, probiotic use, and smoking. Altogether 8676 infants with an eligible genotype were enrolled in the follow-up study before the age of 4 months. The final sample consisted of 7473 children with the age range of 4 to 10 years (as of October 31, 2014). EXPOSURES: Early intake of probiotics. MAIN OUTCOMES AND MEASURES: Islet autoimmunity revealed by specific islet autoantibodies. RESULTS: Early probiotic supplementation (at the age of 0-27 days) was associated with a decreased risk of islet autoimmunity when compared with probiotic supplementation after 27 days or no probiotic supplementation (hazard ratio [HR], 0.66; 95% CI, 0.46-0.94). The association was accounted for by children with the DR3/4 genotype (HR, 0.40; 95% CI, 0.21-0.74) and was absent among other genotypes (HR, 0.97; 95% CI, 0.62-1.54). CONCLUSIONS AND RELEVANCE: Early probiotic supplementation may reduce the risk of islet autoimmunity in children at the highest genetic risk of T1DM. The result needs to be confirmed in further studies before any recommendation of probiotics use is made.


Assuntos
Autoanticorpos/análise , Autoimunidade , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Ilhotas Pancreáticas/imunologia , Probióticos/administração & dosagem , Criança , Pré-Escolar , Suplementos Nutricionais , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Antígenos HLA/genética , Humanos , Lactente , Recém-Nascido , Masculino , Risco
20.
Public Health Nutr ; 19(5): 804-13, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26088478

RESUMO

OBJECTIVE: Non-compliance with food record submission can induce bias in nutritional epidemiological analysis and make it difficult to draw inference from study findings. We examined the impact of demographic, lifestyle and psychosocial factors on such non-compliance during the first 3 years of participation in a multidisciplinary prospective paediatric study. DESIGN: The Environmental Determinants of Diabetes in the Young (TEDDY) study collects a 3 d food record quarterly during the first year of life and semi-annually thereafter. High compliance with food record completion was defined as the participating families submitting one or more days of food record at every scheduled clinic visit. SETTING: Three centres in the USA (Colorado, Georgia/Florida and Washington) and three in Europe (Finland, Germany and Sweden). SUBJECTS: Families who finished the first 3 years of TEDDY participation (n 8096). RESULTS: High compliance was associated with having a single child, older maternal age, higher maternal education and father responding to study questionnaires. Families showing poor compliance were more likely to be living far from the study centres, from ethnic minority groups, living in a crowded household and not attending clinic visits regularly. Postpartum depression, maternal smoking behaviour and mother working outside the home were also independently associated with poor compliance. CONCLUSIONS: These findings identified specific groups for targeted strategies to encourage completion of food records, thereby reducing potential bias in multidisciplinary collaborative research.


Assuntos
Viés , Registros de Dieta , Cooperação do Paciente , Adolescente , Criança , Pré-Escolar , Colorado , Características da Família , Feminino , Finlândia , Florida , Georgia , Alemanha , Humanos , Lactente , Estilo de Vida , Masculino , Avaliação Nutricional , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Suécia , Washington
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