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1.
J Am Chem Soc ; 146(12): 7998-8004, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38507795

RESUMO

A high-surface-area p-type porous Si photocathode containing a covalently immobilized molecular Re catalyst is highly selective for the photoelectrochemical conversion of CO2 to CO. It gives Faradaic efficiencies of up to 90% for CO at potentials of -1.7 V (versus ferrocenium/ferrocene) under 1 sun illumination in an acetonitrile solution containing phenol. The photovoltage is approximately 300 mV based on comparisons with similar n-type porous Si cathodes in the dark. Using an estimate of the equilibrium potential for CO2 reduction to CO under optimized reaction conditions, photoelectrolysis was performed at a small overpotential, and the onset of electrocatalysis in cyclic voltammograms occurred at a modest underpotential. The porous Si photoelectrode is more stable and selective for CO production than the photoelectrode generated by attaching the same Re catalyst to a planar Si wafer. Further, facile characterization of the porous Si-based photoelectrodes using transmission mode FTIR spectroscopy leads to highly reproducible catalytic performance.

2.
J Am Chem Soc ; 145(28): 15507-15527, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37392467

RESUMO

We combine experimental and computational investigations to compare and understand catalytic arene alkenylation using the Pd(II) and Rh(I) precursors Pd(OAc)2 and [(η2-C2H4)2Rh(µ-OAc)]2 with arene, olefin, and Cu(II) carboxylate at elevated temperatures (>120 °C). Under specific conditions, previous computational and experimental efforts have identified heterotrimetallic cyclic PdCu2(η2-C2H4)3(µ-OPiv)6 and [(η2-C2H4)2Rh(µ-OPiv)2]2(µ-Cu) (OPiv = pivalate) species as likely active catalysts for these processes. Further studies of catalyst speciation suggest a complicated equilibrium between Cu(II)-containing complexes containing one Rh or Pd atom with complexes containing two Rh or Pd atoms. At 120 °C, Rh catalysis produces styrene >20-fold more rapidly than Pd. Also, at 120 °C, Rh is ∼98% selective for styrene formation, while Pd is ∼82% selective. Our studies indicate that Pd catalysis has a higher predilection toward olefin functionalization to form undesired vinyl ester, while Rh catalysis is more selective for arene/olefin coupling. However, at elevated temperatures, Pd converts vinyl ester and arene to vinyl arene, which is proposed to occur through low-valent Pd(0) clusters that are formed in situ. Regardless of arene functionality, the regioselectivity for alkenylation of mono-substituted arenes with the Rh catalyst gives an approximate 2:1 meta/para ratio with minimal ortho C-H activation. In contrast, Pd selectivity is significantly influenced by arene electronics, with electron-rich arenes giving an approximate 1:2:2 ortho/meta/para ratio, while the electron-deficient (α,α,α)-trifluorotoluene gives a 3:1 meta/para ratio with minimal ortho functionalization. Kinetic intermolecular arene ethenylation competition experiments find that Rh reacts most rapidly with benzene, and the rate of mono-substituted arene alkenylation does not correlate with arene electronics. In contrast, with Pd catalysis, electron-rich arenes react more rapidly than benzene, while electron-deficient arenes react less rapidly than benzene. These experimental findings, in combination with computational results, are consistent with the arene C-H activation step for Pd catalysis involving significant η1-arenium character due to Pd-mediated electrophilic aromatic substitution character. In contrast, the mechanism for Rh catalysis is not sensitive to arene-substituent electronics, which we propose indicates less electrophilic aromatic substitution character for the Rh-mediated arene C-H activation.

3.
Am J Gastroenterol ; 118(9): 1698-1700, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37159249

RESUMO

INTRODUCTION: Recent reports suggest severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections may increase the risk of celiac disease autoimmunity. This study aims to evaluate potential associations between coronavirus disease 2019 infection and tissue transglutaminase autoantibodies (TGA) immunoglobulin A. METHODS: From 2020 to 2021, cross-sectional screening for SARS-CoV-2 antibodies and TGA was offered to 4,717 children in Colorado through the Autoimmunity Screening for Kids study. Multivariable logistic regression assessed association between previous SARS-CoV-2 infection and TGA positivity. RESULTS: Previous SARS-CoV-2 infection was not associated with TGA positivity (odds ratio 1.02, 95% confidence interval 0.63-1.59; P = 0.95). DISCUSSION: In this large-scale analysis, previous SARS-CoV-2 infection was not associated with celiac disease autoimmunity in Colorado children.


Assuntos
COVID-19 , Doença Celíaca , Humanos , Criança , Adolescente , Autoimunidade , Doença Celíaca/diagnóstico , SARS-CoV-2 , Estudos Transversais , Transglutaminases , Autoanticorpos
4.
Inorg Chem ; 62(5): 2359-2375, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36693077

RESUMO

Eleven 2,2'-bipyridine (bpy) ligands functionalized with attachment groups for covalent immobilization on silicon surfaces were prepared. Five of the ligands feature silatrane functional groups for attachment to metal oxide coatings on the silicon surfaces, while six contain either alkene or alkyne functional groups for attachment to hydrogen-terminated silicon surfaces. The bpy ligands were coordinated to Re(CO)5Cl to form complexes of the type Re(bpy)(CO)3Cl, which are related to known catalysts for CO2 reduction. Six of the new complexes were characterized using X-ray crystallography. As proof of principle, four molecular Re complexes were immobilized on either a thin layer of TiO2 on silicon or hydrogen-terminated silicon. The surface-immobilized complexes were characterized using X-ray photoelectron spectroscopy, IR spectroscopy, and cyclic voltammetry (CV) in the dark and for one representative example in the light. The CO stretching frequencies of the attached complexes were similar to those of the pure molecular complexes, but the CVs were less analogous. For two of the complexes, comparison of the electrocatalytic CO2 reduction performance showed lower CO Faradaic efficiencies for the immobilized complexes than the same complex in solution under similar conditions. In particular, a complex containing a silatrane linked to bpy with an amide linker showed poor catalytic performance and control experiments suggest that amide linkers in conjugation with a redox-active ligand are not stable under highly reducing conditions and alkyl linkers are more stable. A conclusion of this work is that understanding the behavior of molecular Re catalysts attached to semiconducting silicon is more complicated than related complexes, which have previously been immobilized on metallic electrodes.

5.
Inorg Chem ; 61(2): 759-766, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-34962799

RESUMO

Photodriven oxidations of alkanes in trifluoroacetic acid using commercial and synthesized Fe(III) sources as catalyst precursors and dioxygen (O2) as the terminal oxidant are reported. The reactions produce alkyl esters and occur at ambient temperature in the presence of air, and catalytic turnover is observed for the oxidation of methane in a pure O2 atmosphere. Under optimized conditions, approximately 17% conversion of methane to methyl trifluoroacetate at more than 50% selectivity is observed. It is demonstrated that methyl trifluoroacetate is stable under catalytic conditions, and thus overoxidized products are not formed through secondary oxidation of methyl trifluoroacetate.

6.
Diabetologia ; 64(9): 2052-2060, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34272582

RESUMO

AIMS/HYPOTHESIS: It is important to differentiate the two major phenotypes of adult-onset diabetes, autoimmune type 1 diabetes and non-autoimmune type 2 diabetes, especially as type 1 diabetes presents in adulthood. Serum GAD65 autoantibodies (GADA) are the most sensitive biomarker for adult-onset autoimmune type 1 diabetes, but the clinical value of GADA by current standard radiobinding assays (RBA) remains questionable. The present study focused on the clinical utility of GADA differentiated by a new electrochemiluminescence (ECL) assay in patients with adult-onset diabetes. METHODS: Two cohorts were analysed including 771 diabetic participants, 30-70 years old, from the Action LADA study (n = 6156), and 2063 diabetic participants, 20-45 years old, from the Diabetes in Young Adults (DiYA) study. Clinical characteristics of participants, including requirement of early insulin treatment, BMI and development of multiple islet autoantibodies, were analysed according to the status of RBA-GADA and ECL-GADA, respectively, and compared between these two assays. RESULTS: GADA was the most prevalent and predominant autoantibody, >90% in both cohorts. GADA positivity by either RBA or ECL assay significantly discriminated clinical type 1 from type 2 diabetes. However, in both cohorts, participants with ECL-GADA positivity were more likely to require early insulin treatment, have multiple islet autoantibodies, and be less overweight (for all p < 0.0001). However, clinical phenotype, age at diagnosis and BMI independently improved positive predictive value (PPV) for the requirement of insulin treatment, even augmenting ECL-GADA. Participants with GADA detectable by RBA, but not confirmed by ECL, had a phenotype more similar to type 2 diabetes. These RBA-GADA positive individuals had lower affinity GADA compared with participants in which GADA was confirmed by ECL assay. CONCLUSIONS/INTERPRETATION: Detection of GADA by ECL assay, given technical advantages over RBA-GADA, identified adult-onset diabetes patients at higher risk of requiring early insulin treatment, as did clinical phenotype, together allowing for more accurate clinical diagnosis and management.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Adulto , Autoanticorpos , Diabetes Mellitus Tipo 2/diagnóstico , Glutamato Descarboxilase , Humanos , Fenótipo
7.
J Autoimmun ; 122: 102677, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34130115

RESUMO

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by autoimmune destruction of insulin-producing ß-cells in pancreatic islets. Seroconversions to islet autoantibodies (IAbs) precede the disease onset by many years, but the role of humoral autoimmunity in the disease initiation and progression are unclear. In the present study, we identified a new IAb directed to the extracellular epitopes of ZnT8 (ZnT8ec) in newly diagnosed patients with T1D, and demonstrated immunofluorescence staining of the surface of human ß-cells by autoantibodies to ZnT8ec (ZnT8ecA). With the assay specificity set on 99th percentile of 336 healthy controls, the ZnT8ecA positivity rate was 23.6% (74/313) in patients with T1D. Moreover, 30 children in a longitudinal follow up of clinical T1D development were selected for sequential expression of four major IAbs (IAA, GADA, IA-2A and ZnT8icA). Among them, 10 children were ZnT8ecA positive. Remarkably, ZnT8ecA was the earliest IAb to appear in all 10 children. The identification of ZnT8ec as a cell surface target of humoral autoimmunity in the earliest phase of IAb responses opens a new avenue of investigation into the role of IAbs in the development of ß-cell autoimmunity.


Assuntos
Autoanticorpos/sangue , Autoantígenos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Transportador 8 de Zinco/imunologia , Adolescente , Adulto , Idoso , Autoanticorpos/imunologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Epitopos de Linfócito B/imunologia , Feminino , Seguimentos , Humanos , Lactente , Ilhotas Pancreáticas/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Soroconversão , Adulto Jovem
8.
Mol Pharm ; 18(11): 4067-4078, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34672633

RESUMO

Delivery of functional proteins into cells may help us understand how specific protein influences cell behavior as well as treat diseases caused by protein deficiency or loss-of-function mutations. However, protein cannot enter cells by diffusion. In this work, a novel cell biology tool for delivering recombinant proteins into mammalian cells was developed. We hijacked the intracellular transport routes used by the cholera toxin and took advantage of recent development on split intein that is compatible with denatured conditions and shows an exceptional splicing activity to deliver a protein of interest into mammalian cells. Here, we used green fluorescent protein and apoptin as proofs-of-concept. The results demonstrate that the cholera toxin B subunit alone could deliver other recombinant proteins into cells through either covalent conjugation or noncovalent interaction. Our method offers more than 10-fold better delivery efficiency than the tat cell-penetrating peptide and is selective for ganglioside-rich cells. This study adds a useful tool to the receptor-mediated intracellular targeting toolkit and opens possibility for the selective delivery of therapeutic proteins into ganglioside-rich cells.


Assuntos
Toxina da Cólera/química , Portadores de Fármacos/química , Proteínas Recombinantes de Fusão/administração & dosagem , Peptídeos Penetradores de Células/química , Proteínas de Fluorescência Verde/administração & dosagem , Proteínas de Fluorescência Verde/química , Células HEK293 , Humanos , Microscopia Intravital , Estudo de Prova de Conceito , Proteínas Recombinantes de Fusão/química
9.
J Am Chem Soc ; 142(23): 10534-10543, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32453558

RESUMO

Arene alkenylation is commonly achieved by late transition metal-mediated C(sp2)-C(sp2) cross-coupling, but this strategy typically requires prefunctionalized substrates (e.g., with halides or pseudohalides) and/or the presence of a directing group on the arene. Transition metal-mediated arene C-H activation and alkenylation offers an alternative method to functionalize arene substrates. Herein, we report a rhodium-catalyzed oxidative arene alkenylation from arenes and styrenes to prepare stilbene and stilbene derivatives. The reaction is successful with several functional groups on both the arene and the olefin including fluoride, chloride, trifluoromethyl, ester, nitro, acetate, cyanide, and ether groups. Reactions of monosubstituted arenes are selective for alkenylation at the meta and para positions, generally with approximately 2:1 selectivity, respectively. Resveratrol and (E)-1,2,3-trimethoxy-5-(4-methoxystyryl)benzene (DMU-212) are synthesized by this single-step approach in high yield. Comparison with palladium catalysis showed that rhodium catalysis is more selective for meta-functionalization for monosubstituted arenes and that the Rh catalysis has better tolerance of halogen groups.

10.
Br J Nutr ; 121(9): 1039-1048, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30739611

RESUMO

Low urinary iodine concentration (UIC) is associated with dyslipidaemia in adults but is not well characterised in adolescents. Because dyslipidaemia is a cardiovascular risk factor, identifying such an association in adolescents would allow for the prescription of appropriate measures to maintain cardiovascular health. The present study addresses this question using data in the 2001-2012 National Health and Nutrition Examination Survey for 1692 adolescents aged 12-19 years. Primary outcomes were UIC, cardiometabolic risk factors and dyslipidaemia. Data for subjects categorised by low and normal UIC and by sex were analysed by univariate and multivariate logistic regression. Treating UIC as the independent variable, physical activity level, apoB and lipid profiles differed significantly between subjects with low and normal UIC. Subjects with low UIC had a significantly greater risk of elevated total cholesterol (TC) (95 % CI 1·37, 2·81), elevated non-HDL (95 % CI 1·33, 2·76) and elevated LDL (95 % CI 1·83, 4·19) compared with those with normal UIC. Treating UIC as a dependent variable, the risk of low UIC was significantly greater in those with higher apoB (95 % CI 1·52, 19·08), elevated TC (≥4·4mmol/l) (95 % CI 1·37, 2·81) and elevated non-HDL (≥3·11mmol/l) (95 % CI 1·33, 2·76) than in those with normal UIC. These results show that male and female adolescents with low UIC tend to be at greater risk of dyslipidaemia and abnormal cardiometabolic biomarkers, though the specific abnormal parameters differed between sexes. These results may help to identify youth who would benefit from interventions to improve their cardiometabolic risk.


Assuntos
Doenças Cardiovasculares/etiologia , Dislipidemias/etiologia , Iodo/urina , Lipídeos/sangue , Adolescente , Biomarcadores/análise , Criança , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Inquéritos Nutricionais , Estado Nutricional , Fatores de Risco , Adulto Jovem
11.
JAMA ; 328(12): 1252-1255, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35930271

RESUMO

This study screens more than 50 000 youths in diverse populations of Colorado and Bavaria to assess whether previous SARS-CoV-2 infection was associated with autoimmunity, which predicts future type 1 diabetes.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Adolescente , Doenças Assintomáticas/epidemiologia , Autoimunidade , COVID-19/epidemiologia , Criança , Colorado/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/imunologia , Alemanha/epidemiologia , Humanos , SARS-CoV-2
12.
J Endocr Soc ; 8(1): bvad160, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38169963

RESUMO

As screening studies and preventive interventions for type 1 diabetes (T1D) advance rapidly, the utility of islet autoantibodies (IAbs) in T1D prediction comes with challenges for early and accurate disease progression prediction. Refining features of IAbs can provide more accurate risk assessment. The advances in islet autoantibodies assay techniques help to screen out islet autoantibodies with high efficiency and high disease specificity. Exploring new islet autoantibodies to neoepitopes/neoantigens remains a hot research field for improving prediction and disease pathogenesis. We will review the recent research progresses of islet autoantibodies to better understand the utility of islet autoantibodies in prediction of T1D.

13.
Dev Cell ; 58(5): 398-415.e7, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36868233

RESUMO

The cell cycle is key to life. After decades of research, it is unclear whether any parts of this process have yet to be identified. Fam72a is a poorly characterized gene and is evolutionarily conserved across multicellular organisms. Here, we have found that Fam72a is a cell-cycle-regulated gene that is transcriptionally and post-transcriptionally regulated by FoxM1 and APC/C, respectively. Functionally, Fam72a directly binds to tubulin and both the Aα and B56 subunits of PP2A-B56 to modulate tubulin and Mcl1 phosphorylation, which in turn affects the progression of the cell cycle and signaling of apoptosis. Moreover, Fam72a is involved in early responses to chemotherapy, and it efficiently antagonizes various anticancer compounds such as CDK and Bcl2 inhibitors. Thus, Fam72a switches the tumor-suppressive PP2A to be oncogenic by reprogramming its substrates. These findings identify a regulatory axis of PP2A and a protein member in the cell cycle and tumorigenesis regulatory network in human cells.


Assuntos
Proteína Fosfatase 2 , Tubulina (Proteína) , Humanos , Apoptose/genética , Proliferação de Células/genética , Fosforilação , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Tubulina (Proteína)/metabolismo
14.
Front Endocrinol (Lausanne) ; 14: 1110845, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909344

RESUMO

Objective: Intermittently scanned continuous glucose monitoring (isCGM) is used for unblinded or blinded monitoring of interstitial glucose. We aimed to compare the efficacy of blinded and unblinded isCGM with the FreeStyle Libre system for glycemic control in adults with type 1 diabetes (T1D). Research design and methods: This randomized clinical trial conducted between October 2018 and September 2019 across four endocrinology practices in China included 273 adults aged ≥18 years with T1D, who were randomly divided in a 2:1 ratio into the unblinded (n = 199) or blinded isCGM group (n = 78). In the blinded group, the clinician used FreeStyle Libre Pro system for monitoring, but self-monitoring was also performed by the patients. Results: Two hundred sixteen (78%) participants completed the study (152 [75%] in the unblinded and 64 [82%] in the blinded group). At 12 weeks, a significant increase in TIR (3.9-10.0 mmol/L) was only observed in the unblinded group, along with a significant decrease in hyperglycemia (>13.9 mmol/L), hypoglycemia (<3.0 mmol/L), glycemic variability. Further, the mean HbA1c reduction from baseline to 12 weeks was 0.5% in the unblinded isCGM group and 0.4% in the blinded isCGM group respectively (P < 0.001), but the significance did not remain after adjustment for between-group differences. Finally, 99.5% of the blinded isCGM values and 93.8% the of unblinded isCGM values were obtained at the final visit. Conclusions: The unblinded isCGM system was associated with benefits for glucose management, but nearly 100% of the attempted profiles were obtained successfully with the blinded isCGM system. Thus, combining real-time and retrospective data with isCGM might be the most impactful way to utilize flash glycemic monitoring devices.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Adulto , Adolescente , Glicemia , Automonitorização da Glicemia , Estudos Retrospectivos , Controle Glicêmico
15.
Diabetes Technol Ther ; 25(7): 492-496, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36989496

RESUMO

Objective: To assess whether the immunogenicity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines or breakthrough infection rates differ between patients with type 1 diabetes (T1D) and control subjects. Research Design and Methods: A prospective 12-month follow-up of 27 adults with T1D and 89 control subjects who received at least two doses of either the mRNA-1273 or BNT162b2 vaccine. Primary outcomes: total antibodies against the receptor-binding domain and neutralizing antibodies. A multivariate repeated measures model evaluated potential determinants of antibody response. Results: Neither antibody levels nor breakthrough infection rates after vaccination differed in T1D and non-T1D groups. Older age predicted lower antibody levels, whereas SARS-CoV-2 infection or booster vaccine resulted in higher antibody levels in both groups. mRNA-1273 was associated with higher antibody levels than BNT162b2 until 6 months after the first dose. Conclusions: Persons with and without T1D have similar humoral antibody responses to SARS-CoV-2 mRNA vaccines during 12-months of follow-up.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Adulto , Humanos , Vacinas contra COVID-19 , Vacina BNT162 , Vacina de mRNA-1273 contra 2019-nCoV , SARS-CoV-2 , Estudos Prospectivos , COVID-19/prevenção & controle , Infecções Irruptivas , Vacinas de mRNA
16.
IEEE Trans Biomed Eng ; 70(4): 1231-1241, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36215340

RESUMO

OBJECTIVE: Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique used to generate conduction currents in the head and disrupt brain functions. To rapidly evaluate the tDCS-induced current density in near real-time, this paper proposes a deep learning-based emulator, named DeeptDCS. METHODS: The emulator leverages Attention U-net taking the volume conductor models (VCMs) of head tissues as inputs and outputting the three-dimensional current density distribution across the entire head. The electrode configurations are also incorporated into VCMs without increasing the number of input channels; this enables the straightforward incorporation of the non-parametric features of electrodes (e.g., thickness, shape, size, and position) in the training and testing of the proposed emulator. RESULTS: Attention U-net outperforms standard U-net and its other three variants (Residual U-net, Attention Residual U-net, and Multi-scale Residual U-net) in terms of accuracy. The generalization ability of DeeptDCS to non-trained electrode configurations can be greatly enhanced through fine-tuning the model. The computational time required by one emulation via DeeptDCS is a fraction of a second. CONCLUSION: DeeptDCS is at least two orders of magnitudes faster than a physics-based open-source simulator, while providing satisfactorily accurate results. SIGNIFICANCE: The high computational efficiency permits the use of DeeptDCS in applications requiring its repetitive execution, such as uncertainty quantification and optimization studies of tDCS.


Assuntos
Aprendizado Profundo , Estimulação Transcraniana por Corrente Contínua , Estimulação Transcraniana por Corrente Contínua/métodos , Encéfalo/fisiologia , Cabeça , Eletrodos
17.
J Prim Care Community Health ; 14: 21501319231189147, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37501515

RESUMO

There are few estimates of the seroprevalence of SARS-CoV-2 antibodies among children in the United States. We measured vaccine and infection induced seroprevalence among nearly 5000 healthy 1 to 17-year-old children in Colorado from 2020 to 2021. By December 2021, 89% of older children, ages 12 to 18, had antibodies detected. The increase was largely driven from vaccination rather than infection.


Assuntos
COVID-19 , SARS-CoV-2 , Criança , Humanos , Adolescente , Lactente , Pré-Escolar , Colorado/epidemiologia , Prevalência , Estudos Soroepidemiológicos , COVID-19/epidemiologia , Anticorpos Antivirais
18.
Front Clin Diabetes Healthc ; 3: 1034698, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36992730

RESUMO

While worldwide prevention efforts for type 1 diabetes (T1D) are underway to abrogate or slow progression to diabetes, mass screening of islet autoantibodies (IAbs) in the general population is urgently needed. IAbs, the most reliable biomarkers, play an essential role in prediction and clinical diagnosis of T1D. Through laboratory proficiency programs and harmonization efforts, a radio-binding assay (RBA) has been well established as the current 'gold' standard assay for all four IAbs. However, in view of the need for large-scale screening in the non-diabetic population, RBA consistently faces two fundamental challenges, cost-efficiency and disease specificity. While all four IAbs are important for disease prediction, the RBA platform, with a separate IAb test format is laborious, inefficient and expensive. Furthermore, the majority of IAb positivity in screening, especially from individuals with single IAb were found to be low risk with low affinity. It is well documented from multiple clinical studies that IAbs with low affinity are low risk with less or no disease relevance. At present, two non-radioactive multiplex assays, a 3-assay ELISA combining three IAbs and a multiplex ECL assay combining all four IAbs, have been successfully used as the primary methods for general population screenings in Germany and the US, respectively. Recently, the TrialNet Pathway to Prevention study has been organizing an IAb workshop which aims to analyze the 5-year T1D predictive values of IAbs. A T1D-specific assay with high efficiency, low cost and requiring low volume of sample will definitely be necessary to benefit general population screening.

19.
J Clin Endocrinol Metab ; 107(7): 1825-1832, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35460250

RESUMO

CONTEXT: Islet autoantibodies (IAbs) are currently the most reliable indicators of islet autoimmunity. However, IAbs do not fully meet the need for the prediction and intervention of type 1 diabetes (T1D). Serological proteins should be great sources for biomarkers. OBJECTIVE: This work aimed to identify new proteomic biomarkers with the technology of an expression-based genome-wide association study (eGWAS) in children newly diagnosed with T1D. METHODS: In an attempt to identify additional biomarkers, we performed an eGWAS using microarray data from 169 arrays of the pancreatic islets of T1D rodents (78 T1D cases and 91 controls). We ranked all 16 099 protein-coding genes by the likelihood of differential expression in the pancreatic islets. Our top 20 secreted proteins were screened in 170 children including 100 newly diagnosed T1D, and 50 type 2 diabetes (T2D) and 20 age-matched healthy children. With 6 proteins showing significance, we further conducted a validation study using the second independent set of 400 samples from children including 200 newly diagnosed with T1D, 100 T2D, and 100 age-matched controls. RESULTS: We identified 2 serum proteins that were significantly changed in T1D vs both control and T2D, and 5 serum proteins were significantly changed both in T1D and T2D vs control. Serum osteopontin (OPN) levels were uniquely higher in T1D (T1D vs controls, P = 1.29E-13 ~ 9.38E-7, T1D vs T2D, P = 2.65E-8 ~ 1.58E-7) with no difference between T2D and healthy control individuals. Serum interleukin 1 receptor antagonist (IL-1RA) levels were lower in T1D compared both with T2D (P = 3.36E-9~0.0236) and healthy participants (P = 1.09E-79 ~ 2.00E-12). CONCLUSION: Our results suggest that OPN and IL1-RA could be candidates for useful biomarkers for T1D in children.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Proteína Antagonista do Receptor de Interleucina 1/genética , Autoanticorpos , Biomarcadores , Criança , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Estudo de Associação Genômica Ampla , Humanos , Osteopontina/genética , Proteômica
20.
J Vis Exp ; (185)2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35876559

RESUMO

An ongoing clinical trial, Autoimmunity Screening for Kids (ASK), is the first screening study in the general population for type 1 diabetes (T1D) and celiac disease in the United States. With the coronavirus disease 2019 (COVID-19) pandemic, the epidemiology of COVID-19 in the general population and knowledge about the association between COVID-19 infection and T1D development are urgently needed. The currently standard screening method of the radio-binding assay (RBA) has met two great challenges: low efficiency with a single assay format and low disease specificity with a large proportion of low-affinity antibodies generated in screening. With the platform of the multiplex electrochemiluminescence (ECL) assay we established previously, a novel 6-Plex ECL assay was developed that combines, in a single well, all four islet autoantibodies (IAbs) to insulin, glutamic acid decarboxylase (GAD65), insulinoma antigen 2 (IA-2), and Zinc transporter 8 (ZnT8) for T1D, transglutaminase autoantibodies (TGA) for celiac disease, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain (RBD) antibodies for COVID-19. The assay was validated in blind using 880 samples from the ASK study, including 325 positive samples and 555 all antibody-negative samples, and compared with the standard RBAs and a single ECL assay. With the advantages of high efficiency, low cost, and low serum volume, this assay has been accepted as the primary screening tool for the ASK study.


Assuntos
COVID-19 , Doença Celíaca , Diabetes Mellitus Tipo 1 , Autoanticorpos , COVID-19/diagnóstico , Doença Celíaca/diagnóstico , Doença Celíaca/epidemiologia , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/epidemiologia , Glutamato Descarboxilase , Humanos , SARS-CoV-2 , Sensibilidade e Especificidade
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