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1.
Nanoscale Horiz ; 9(2): 278-284, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38044846

RESUMEN

High-performance semiconductor materials and devices are needed to supply the growing energy and computing demand. Organic semiconductors (OSCs) are attractive options for opto-electronic devices, due to their low cost, extensive tunability, easy fabrication, and flexibility. Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been extensively studied due to their high carrier mobility, stability and opto-electronic tunability. Although molecular charge transfer doping affords widely tunable carrier density and conductivity in s-SWCNTs (and OSCs in general), a pervasive challenge for such systems is reliable measurement of charge carrier density and mobility. In this work we demonstrate a direct quantification of charge carrier density, and by extension carrier mobility, in chemically doped s-SWCNTs by a nuclear magnetic resonance approach. The experimental results are verified by a phase-space filling doping model, and we suggest this approach should be broadly applicable for OSCs. Our results show that hole mobility in doped s-SWCNT networks increases with increasing charge carrier density, a finding that is contrary to that expected for mobility limited by ionized impurity scattering. We discuss the implications of this important finding for additional tunability and applicability of s-SWCNT and OSC devices.

2.
Cureus ; 15(7): e41696, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37575726

RESUMEN

With the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, the Centers for Disease Control and Prevention (CDC) authorized the third dose of the Pfizer-BioNTech (BNT162b2) vaccine with the rationale for prolonged elevation of anti-SARS-CoV-2 antibody titers and protection against the SARS-CoV-2 virus. To better understand how administration of the third dose of the Pfizer/BioNTech coronavirus disease 2019 (COVID-19) vaccine affects the incidence and severity of SARS-CoV-2 infections, we administered the third dose of the Pfizer-BioNTech (BNT162b2) to 189 participants. Blood samples were collected from participants during each of their scheduled visits (baseline, week two, week 12, and week 24) and tested for semi-quantitative anti-SARS-CoV-2 immunoglobulin G (IgG) titers. Our results showed that administration of the third dose of the Pfizer-BioNTech (BNT162b2) vaccine elicited elevated anti-SARS-CoV-2 IgG antibodies for the 24-week duration of the study. IgG antibody titers were greatest in week two, and progressively decreased by week 12 and week 24, with statistically significant differences between the IgG antibody titers for each collection date.

3.
ACS Nano ; 17(15): 14916-14929, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37494884

RESUMEN

Controlling the binding of functional organic molecules on quantum dot (QD) surfaces and the resulting ligand/QD interfacial structure determines the resulting organic-inorganic hybrid behavior. In this study, we vary the binding of tetracenedicarboxylate ligands bound to PbS QDs cast in thin films by performing solid-state ligand exchange of as-produced bound oleate ligands. We employ comprehensive Fourier-transform infrared (FTIR) analysis coupled with ultraviolet-visible (UV-vis) spectrophotometric measurements, transient absorption, and Density Functional Theory (DFT) simulations to study the QD/ligand surface structure and resulting optoelectronic properties. We find that there are three primary QD/diacid structures, each with a distinct binding mode dictated by the QD-ligand and ligand-ligand intermolecular and steric interactions. They can be accessed nearly independently of one another via different input ligand concentrations. Low concentrations produce mixed oleate/tetracene ligand structures where the tetracene carboxylates tilt toward QD surfaces. Intermediate concentrations produce mixed oleate/tetracene ligand structures with ligand-ligand interactions through intramolecular hydrogen bonding with the ligands perpendicular to the QD surface and weaker QD/ligand electronic interactions. High concentrations result in full ligand exchange, and the ligands tilt toward the surface while the QD film compacts. When the tetracene ligands tilt or lie flat on the QD surface, the benzene ring π-system interacts strongly with the p-orbitals at the PbS surface and produces strong QD-ligand interactions evidenced through QD/ligand state mixing, with a coupling energy of ≈700 meV.

4.
Mol Cell Proteomics ; 20: 100069, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33716169

RESUMEN

The dynamic modification of specific serine and threonine residues of intracellular proteins by O-linked N-acetyl-ß-D-glucosamine (O-GlcNAc) mitigates injury and promotes cytoprotection in a variety of stress models. The O-GlcNAc transferase (OGT) and the O-GlcNAcase are the sole enzymes that add and remove O-GlcNAc, respectively, from thousands of substrates. It remains unclear how just two enzymes can be specifically controlled to affect glycosylation of target proteins and signaling pathways both basally and in response to stress. Several lines of evidence suggest that protein interactors regulate these responses by affecting OGT and O-GlcNAcase activity, localization, and substrate specificity. To provide insight into the mechanisms by which OGT function is controlled, we have used quantitative proteomics to define OGT's basal and stress-induced interactomes. OGT and its interaction partners were immunoprecipitated from OGT WT, null, and hydrogen peroxide-treated cell lysates that had been isotopically labeled with light, medium, and heavy lysine and arginine (stable isotopic labeling of amino acids in cell culture). In total, more than 130 proteins were found to interact with OGT, many of which change their association upon hydrogen peroxide stress. These proteins include the major OGT cleavage and glycosylation substrate, host cell factor 1, which demonstrated a time-dependent dissociation after stress. To validate less well-characterized interactors, such as glyceraldehyde 3-phosphate dehydrogenase and histone deacetylase 1, we turned to parallel reaction monitoring, which recapitulated our discovery-based stable isotopic labeling of amino acids in cell culture approach. Although the majority of proteins identified are novel OGT interactors, 64% of them are previously characterized glycosylation targets that contain varied domain architecture and function. Together these data demonstrate that OGT interacts with unique and specific interactors in a stress-responsive manner.


Asunto(s)
N-Acetilglucosaminiltransferasas/metabolismo , Estrés Oxidativo , Animales , Células Cultivadas , Fibroblastos/metabolismo , Ratones , N-Acetilglucosaminiltransferasas/genética , Mapas de Interacción de Proteínas , Proteómica
5.
Eur J Endocrinol ; 184(3): 373-381, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33444227

RESUMEN

OBJECTIVE: While vitamin D regulates immune cells, little is known about it in autoimmune Addison's disease (AAD). We investigated the vitamin D status in AAD patients from five European populations to assess its deficiency. In addition, we studied two case-control cohorts for vitamin D metabolism and pathway genes. DESIGN: Cross-sectional study. METHODS: A total of 1028 patients with AAD from Germany (n = 239), Italy (n = 328), Norway (n = 378), UK (n = 44) and Poland (n = 39) and 679 controls from Germany (n = 301) and Norway (n = 378) were studied for 25(OH)D3 (primary objective). Secondary objectives (1,25(OH)2D3 and pathway genes) were examined in case-controls from Germany and Norway correlating 25(OH)D3 and single nucleotide polymorphisms within genes encoding the vitamin D receptor (VDR), 1-α-hydroxylase (CYP27B1), 25-hydroxylase (CYP2R1), 24-hydroxylase (CYP24A1) and vitamin D binding protein (GC/DBP). RESULTS: Vitamin D deficiency (25(OH)D3 10-20 ng/mL) was highly prevalent in AAD patients (34-57%), 5-22% were severely deficient (<10 ng/mL), 28-38% insufficient (20-30 ng/mL) and only 7-14% sufficient (>30 ng/mL). Lower 25(OH)D3 and 1,25(OH)2D3 levels were observed both in Norwegian and German AAD (P = 0.03/0.003 and P = 1 × 10-5/< 1 × 10-7, respectively) the former was associated with CYP2R1 (rs1553006) genotype G. Whereas controls achieved sufficient median 25(OH)D3 in summers (21.4 to 21.9 ng/mL), AAD patients remained largely deficient (18.0 to 21.2 ng/mL) and synthesize less 1,25(OH)2D3. CONCLUSION: Vitamin D deficiency and insufficiency are highly prevalent in AAD patients. The vitamin D status of AAD may be influenced by genetic factors and suggests individual vitamin D requirements throughout the year.


Asunto(s)
Enfermedad de Addison/complicaciones , Calcifediol/sangre , Genotipo , Polimorfismo de Nucleótido Simple , Deficiencia de Vitamina D/complicaciones , Enfermedad de Addison/sangre , Enfermedad de Addison/genética , Adulto , Calcitriol/sangre , Estudios de Casos y Controles , Estudios de Cohortes , Estudios Transversales , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores de Calcitriol/genética , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/genética , Proteína de Unión a Vitamina D/genética , Vitamina D3 24-Hidroxilasa/genética
6.
Front Immunol ; 11: 583709, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33365026

RESUMEN

Context: Autoimmune polyglandular syndrome (APS-2: autoimmune Addison's disease or type 1 diabetes) is conferred by predisposing HLA molecules, vitamin D deficiency, and heritable susceptibility. Organ destruction is accompanied by cytokine alterations. We addressed the monocytic cytokines of two distinct APS-2 cohorts, effects of vitamin D and HLA DQ risk. Methods: APS-2 patients (n = 30) and healthy controls (n = 30) were genotyped for HLA DQA1/DQB1 and their CD14+ monocytes stimulated with IL1ß and/or 1,25(OH)2D3 for 24 h. Immune regulatory molecules (IL-6, IL-10, IL-23A, IL-15, CCL-2, PD-L1), vitamin D pathway gene transcripts (CYP24A1, CYP27B1, VDR), and CD14 were analyzed by enzyme-linked immunosorbent assay and RTqPCR. Results: Pro-inflammatory CCL-2 was higher in APS-2 patients than in controls (p = 0.001), whereas IL-6 showed a trend - (p = 0.1). In vitro treatment with 1,25(OH)2D3 reduced proinflammatory cytokines (IL-6, CCL-2, IL-23A, IL-15) whereas anti-inflammatory cytokines (IL-10 and PD-L1) rose both in APS-type 1 diabetes and APS-Addison´s disease. Patients with adrenal autoimmunity showed a stronger response to vitamin D. Expression of IL-23A and vitamin D pathway genes VDR and CYP27B1 varied by HLA genotype and was lower in healthy individuals with high-risk HLA (p = 0.0025; p = 0.04), while healthy controls with low-risk HLA showed a stronger IL-10 and CD14 expression (p = 0.01; p = 0.03). Conclusion: 1,25(OH)2D3 regulates the monocytic response in APS-2 disorders type 1 diabetes or Addison´s disease. The monocytic cytokine profile of individuals carrying HLA high-risk alleles is proinflammatory, enhances polyglandular autoimmunity and can be targeted by vitamin D.


Asunto(s)
Citocinas/inmunología , Antígenos HLA-DQ/inmunología , Monocitos/inmunología , Poliendocrinopatías Autoinmunes/inmunología , Vitamina D/inmunología , Adulto , Alelos , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Inflamación/inmunología , Masculino , Persona de Mediana Edad , Transducción de Señal/inmunología
7.
Horm Metab Res ; 52(7): 492-499, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32542627

RESUMEN

Variants of vitamin D metabolism-genes may predispose to type 2 diabetes (T2D). This study investigated the impact of these variants on disease susceptibility, Vitamin D, parathyroid hormone, C-peptide and HbA1c levels before and after cholecalciferol supplementation in patients with T2D.Twelve polymorphisms within CYP2R1, CYP27B1, DBP, VDR and CYP24A1 were genotyped in 553 T2D patients and 916 controls. In addition 65 patients receiving either cholecalciferol or placebo were analyzed during 6 months intervention and 6 months follow-up.T2D risk alleles are VDR rs7975232 "G" (pc=0.031), rs1544410 "G" (pc=0.027) and CYP2R1 rs10741657 "A" (pc=0.016). Patients with genotypes CYP27B1 rs10877012 "CC" (pc=4x10-5), DBP rs7041 "GG" (pc=0.003), rs4588 "CC" (pc = 3x10-4), CYP24A1 rs2585426 "CG" (pc=0.006) and rs2248137 "CG" (pc=0.001) showed lower 25(OH)D3 and DBP rs4588 "CC" lower 1,25(OH)2D3 levels (pc=0.005). Whereas DBP rs4588 "CC" (pc=0.009), CYP27B1 rs10877012 "AC" (pc=0.059), VDR rs7975323 "AG" (pc=0.033) and rs1544410 "GG" (pc=0.013) are associated with higher 25(OH)D3 levels at 6 months' follow-up. Significant PTH suppression was detected for CYP2R1 "AG" (pc=0.002), DBP rs4588 "CC" (pc<0.001), VDR rs110735810 "CT" (pc<0.001) and CYP24A1 rs2248137 "GG" (pc=0.021).Genetic variants of the vitamin D system predispose to type 2 diabetes and regulate - partially - vitamin D metabolism, concentrations and the vitamin D status. Vitamin D insufficiency is a T2D risk factor. The response to cholecalciferol supplementation can be measured as 25(OH)D3 increment and PTH suppression. This process is regulated by genes of the vitamin D system conferring modest T2D risk.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Deficiencia de Vitamina D/genética , Vitamina D/uso terapéutico , 25-Hidroxivitamina D3 1-alfa-Hidroxilasa/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Colestanotriol 26-Monooxigenasa/genética , Estudios de Cohortes , Familia 2 del Citocromo P450/genética , Diabetes Mellitus Tipo 2/metabolismo , Suplementos Dietéticos , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Redes y Vías Metabólicas/genética , Persona de Mediana Edad , Pruebas de Farmacogenómica , Polimorfismo de Nucleótido Simple , Datos Preliminares , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptores de Calcitriol/genética , Resultado del Tratamiento , Vitamina D/metabolismo , Deficiencia de Vitamina D/tratamiento farmacológico , Deficiencia de Vitamina D/metabolismo , Proteína de Unión a Vitamina D/genética , Vitamina D3 24-Hidroxilasa/genética
8.
J Cross Cult Gerontol ; 34(4): 439-459, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31691072

RESUMEN

BACKGROUND: The aims of this paper are to present the evolutionary development of the Community Model of Healthy Aging (CMHA) and to show the main results of the community gerontology studies framed in each of the stages of the CMHA. METHOD: The study employs a qualitative community-based participatory research approach. We also measured several biochemical parameters, social support networks, and indicators of physical and cognitive functioning. RESULTS: We identified three stages in the development of the CMHA. The first stage was informative (CMHA-I, 1994-2000) with more than 70% of the older adults participating in self-care programs for health. The second stage was formative (CMHA-F, 2001-2015) with more than 80% of older adults participating in self-care, mutual aid, and self-management programs. The third stage was emancipatory (CMHA-E, 2016-2018). In this last stage, we added resilience and generativity as basic elements to strengthen and enhance human capacities during aging, and more than 90% of older adults made optimal use of social support networks as a key strategy. CONCLUSION: Our findings suggest that the addition of resilience and generativity in the CMHA contributed to the active participation of older adults in the maintenance of functioning and the prevention and control of diseases linked to aging.


Asunto(s)
Participación de la Comunidad , Geriatría , Envejecimiento Saludable/psicología , Relaciones Intergeneracionales/etnología , Resiliencia Psicológica , Anciano , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Autocuidado , Apoyo Social
9.
J Chem Phys ; 151(11): 114111, 2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31542005

RESUMEN

Photoelectrochemical (PEC) water splitting is one of the most important approaches being investigated for solar fuel generation. In this study, we determine the maximum thermodynamic power conversion efficiencies (PCEs) of PEC water splitting two-bandgap tandem devices that produce multiple carriers per photon absorbed via Multiple Exciton Generation (MEG) or Singlet Fission (SF) and in the presence of solar concentration. Here, we employ a detailed balance thermodynamic analysis to determine the effects of top cell thickness, solar concentration, carrier multiplication, electrode overvoltage (VO), and water absorption on PEC power conversion efficiency for water splitting cells. We have found a maximum PEC power conversion efficiency of 62.9% in cells using two ideal tandem MEG absorbers with bandgaps of 0.3 and 1.2 eV at 1000-suns solar concentration and 0 overvoltage; the maximum PCE for two tandem SF absorbers under the same conditions is nearly the same at 59% with the same values for the absorption thresholds. A very interesting and important result was that, upon thinning the top cell, the range of viable bandgaps for both the top and bottom cells is extended by as much as 0.5-1 eV while still maintaining high maximum conversion efficiency (60-63%). The effects of imposing different solar concentrations from 1X to 1000X and having different tandem configurations of SF and MEG layers were also studied.

10.
J Am Chem Soc ; 141(30): 12121-12127, 2019 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-31276394

RESUMEN

We developed a method to colloidally synthesize atomically thin metal sulfides (ATMS). Unlike conventional 2D systems such as MoS2 and graphene, none of the systems developed here are inherently layered compounds nor have known layered polymorphs in their bulk forms. The synthesis proceeds via a cation-exchange reaction starting from single- and multi-layer Ag2S and going to various metal sulfides. The synthesized ATMS retain their size and shape during the cation-exchange reaction and are either single-layer or a few-layer, depending on the starting Ag2S samples. They have lateral dimensions on the order of 5-10 nm and are colloidally stabilized by Z- and L-type ligands. Here, we demonstrate the synthesis of single-layer and a few-layer ZnS, CdS, CoS2, and PbS. We find that the optical properties of these ATMS are quite distinct from the platelet or quantum-dot versions of the same metal sulfides.

11.
ACS Nano ; 13(4): 3839-3846, 2019 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-30855942

RESUMEN

We present a combined experimental and theoretical study of ligand-ligand cooperativity during X-type carboxylate-to-carboxylate ligand exchange reactions on PbS quantum dot surfaces. We find that the ligand dipole moment (varied through changing the substituents on the benzene ring of cinnamic acid derivatives) impacts the ligand-exchange isotherms; in particular, ligands with large electron withdrawing character result in a sharper transition from an oleate-dominated ligand shell to a cinnamate-dominated ligand shell. We developed a two-dimensional lattice model to simulate the ligand-exchange isotherms that accounts for the difference in ligand binding energy as well as ligand-ligand cooperativity. Our model shows that ligands with larger ligand-ligand coupling energy exhibit sharper isotherms indicating an order-disorder phase transition. Finally, we developed an anisotropic Janus ligand shell by taking advantage of the ligand-ligand cooperative ligand exchanges. We monitored the Janus ligand shell using 19F nuclear magnetic resonance, showing that when the ligand-ligand coupling energy falls within the order region of the phase diagram, Janus ligand shells can be constructed.

12.
Chem Biodivers ; 16(4): e1800525, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30614195

RESUMEN

A natural and biocompatible extract of garlic as a support, decorated with silver nanoparticles, is a proposal to generate an effective antifungal agent against dermatophytes at low concentrations. Silver nanoparticles (AgNPs) with a diameter of 26±7 nm were synthesized and their antimycotic activity was examined against Trichophyton rubrum (T. rubrum), inhibiting 94 % of growth at a concentration of 0.08 mg ml-1 . Allium sativum (garlic) extract was also obtained (AsExt), and its MIC was 0.04 mg ml-1 . To increase the antifungal capacity of those systems, AsExt was decorated with AgNPs, obtaining AsExt-AgNPs. Using an AsExt concentration of 0.04 mg ml-1 in independent experiments with concentrations from 0.01 to 0.08 mg ml-1 of AgNPs, it was possible to inhibit T. rubrum at all AgNPs concentrations; it proves a synergistic effect between AgNPs and AsExt. Even if 1 % of the minimum inhibitory concentration of AsExt (0.0004 mg ml-1 ) is used, it was possible to inhibit T. rubrum at all concentrations of AgNPs, demonstrating the successful antimycotic activity potentiation when combining AsExt and AgNPs.


Asunto(s)
Antifúngicos/farmacología , Ajo/química , Nanopartículas/química , Extractos Vegetales/farmacología , Plata/farmacología , Trichophyton/efectos de los fármacos , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plata/química , Relación Estructura-Actividad
13.
J Steroid Biochem Mol Biol ; 186: 130-135, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30336275

RESUMEN

Elevated sphingosine 1-phopshate (S1P) concentration was observed in type 2 diabetes mellitus (T2D). On the other side, 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) can influence the formation of sphingosine 1-phopshate (S1P) and the expression of S1P receptors, which are known to be involved in T2D. In order to evaluate mechanisms for the antiinflammatory potential of 1,25(OH)2D3, we investigated whether 1,25(OH)2D3 alters S1P signaling and metabolism in human CD14+ monocytes. Primary monocytes isolated from healthy controls (HC) and T2D patients were treated for 24 h with 10 nM 1,25(OH)2D3 in the absence or presence of 500 IU/ml interleukin-(IL)-1ß. Thereafter, sphingosine kinase (SPHK)1, SPHK2 and S1P receptor 1-5 (S1P1-5) mRNA expression levels were measured by TaqMan™ analyses. Sphingolipid levels in cell supernatant were determined by high-performance liquid chromatography/tandem mass spectrometry (LC-MS/MS). 1,25(OH)2D3 treatment downregulated S1P1 and S1P2 mRNA expression compared to untreated monocytes of HC and T2D patients. In contrast, SPHK1, S1P3 and S1P4 mRNA expression levels were upregulated by 1,25(OH)2D3 treatment compared to the respective controls. Furthermore, reduced S1P2 and increased S1P3 and S1P4 mRNA expression levels upon treatment with 1,25(OH)2D3 occurred in the presence of IL-1ß. Additionally, S1P levels in cell supernatants were decreased in monocytes from HC and T2D patients by 1,25(OH)2D3 with or without IL-1ß costimulation. The levels of sphingosine in cell supernatants were not influenced by 1,25(OH)2D3. Overall, our results demonstrate for the first time that 1,25(OH)2D3 treatment can influence S1P receptor and SPHK expression and S1P levels in primary monocytes of both HC and subjects with T2D. These findings justify further investigations into the sphingolipid metabolism and potential benefits of vitamin D treatment in diabetes.


Asunto(s)
Calcitriol/farmacología , Diabetes Mellitus Tipo 2/metabolismo , Lisofosfolípidos/metabolismo , Monocitos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Esfingosina/análogos & derivados , Vitaminas/farmacología , Adulto , Anciano , Células Cultivadas , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Lisofosfolípidos/genética , Masculino , Persona de Mediana Edad , Monocitos/metabolismo , Receptores de Lisoesfingolípidos/genética , Receptores de Lisoesfingolípidos/metabolismo , Esfingosina/genética , Esfingosina/metabolismo
14.
J Steroid Biochem Mol Biol ; 187: 52-57, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30521849

RESUMEN

The arachidonate 5-lipoxygenase (ALOX5) pathway has been implicated in chronic inflammatory disease which may be influenced by vitamin D due to vitamin D response elements (VDRE). We investigated an ALOX5 polymorphism (rs4987105) in patients with type 2 diabetes (T2D) and the in vitro effects of calcitriol (1,25(OH)2D3) on ALOX5 metabolism in monocytes of T2D patients and healthy controls (HC). 533 T2D and 473 HC were genotyped for the rs4987105 polymorphism. In addition, the 25(OH)D3 and 1,25(OH)2D3 plasma levels were measured in both cohorts. Further C-reactive protein (CRP) was determined in T2D patients. Our results demonstrate, that genotype CC and the allele C of ALOX5 rs4987105 polymorphism were more frequent in T2D compared to HC (OR = 1.44; 95% CI: 1.12-1.84; p < 0.05). Lower levels of both vitamin D metabolites (p < 0.0001 respectively) were found in the CC genotyped T2D patients compared to CC genotyped HC. In addition, CC genotyped T2D patients had higher levels of CRP compared to CT and TT genotyped T2D patients, (p < 0.01). In order to evaluate the impact of calcitriol in primary isolated monocytes, we isolated monocytes of 20 T2D patients and 20 HC. The cells were treated with 1,25(OH)2D3 and interleukin-1beta (IL-1ß) for 24 h. The following genes were analysed for expression changes: ALOX5, leukotriene A4 hydrolase (LTA4H), leukotriene B4 receptor type 1 (LTB4R1) and CD14. Treatment with IL-1ß+1,25(OH)2D3 increased ALOX5, LTA4H and LTB4R1 and CD14 mRNA in both T2D patients and HC (p < 0.0001, respectively). In addition, IL-1ß+1,25(OH)2D3 treatment led to higher ALOX5, LTA4H and CD14 mRNA levels in T2D patients compared to HC (p < 0.001, p < 0.05, p ≤ 0.05, respectively). In conclusion, ALOX5 rs4987105 allele C confers susceptibility to T2D, lower vitamin D metabolites and higher CRP levels complement this association. Additionally, IL-1ß+1,25(OH)2D3 treatment on, ALOX5, LTA4H and CD14 mRNA indicate a diabetes specific modulation. These findings identify a novel pathway in T2D potentially amenable for individualized therapeutic targeting.


Asunto(s)
Araquidonato 5-Lipooxigenasa/genética , Calcitriol/uso terapéutico , Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleótido Simple , Vitaminas/uso terapéutico , Proteína C-Reactiva/análisis , Células Cultivadas , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Interleucina-1beta/uso terapéutico , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Vitamina D/sangre
15.
J Clin Endocrinol Metab ; 104(6): 1907-1916, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30590628

RESUMEN

CONTEXT: Autoimmune endocrinopathies result from environmental triggers on the genetic background of risk alleles, especially HLA-DR and HLA-DQ with alanine (Ala) in HLA-DQB1 position 57 (Ala57), whereas amino acid Asp57 is protective. OBJECTIVES: Differentiate the effects of HLA-DQB1 amino acid variants at position 57 in adult patients with isolated endocrinopathies and autoimmune polyglandular syndrome type 2 (APS-2) compared with healthy controls in relation to gender. SETTING: University Hospital Frankfurt, Frankfurt, Germany. PARTICIPANTS: Two hundred seventy-eight patients with APS-2 and 1373 patients with isolated endocrinopathies: [type 1 diabetes (T1D), n = 867], Addison disease (AD, n = 185), autoimmune thyroiditis (AIT, n = 321) and 526 healthy controls. RESULTS: Homozygous HLA-DQB1 Ala57 was more frequent in polyglandular T1D/AIT (OR 11.7, Pc = 3 × 10-7) and AD/AIT (OR 4.0, Pc = 3 × 10-7), as well as in isolated T1D (OR 9.7, Pc = 3 × 10-7) and AD (OR 3.1, Pc = 3 × 10-7). Heterozygous HLA-DQB1 57 Ala/non-Ala was increased in women with isolated AD and polyglandular AD/AIT (both OR 1.7, Pc= 0.02) whereas the same amino acid variant was overrepresented in men with T1D compared with women (OR 1.6, Pc = 0.004). The amino acid Ala57 was more frequent (OR 2.0, Pc = 0.02) and the amino acid Asp57 was much more rare (OR 0.4, Pc = 0.007) in the APS-2 cohort T1D/AIT than in AD/AIT. CONCLUSION: HLA-DQB1 confers strong susceptibility by Ala57 homozygosity and protection by non-Ala57, both in adult isolated and polyglandular diseases. Frequencies of HLA-DQB1 amino acids differentiate between APS-2 T1D/AIT and AD/AIT. HLA-DQB1 Ala57 heterozygous women are at increased risk for AD or AIT, whereas men were found to have an increased susceptibility for T1D.


Asunto(s)
Enfermedad de Addison/genética , Diabetes Mellitus Tipo 1/genética , Cadenas beta de HLA-DQ/genética , Poliendocrinopatías Autoinmunes/genética , Tiroiditis Autoinmune/genética , Adulto , Alanina/genética , Sustitución de Aminoácidos , Asparagina/genética , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Voluntarios Sanos , Heterocigoto , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
16.
Artículo en Inglés | MEDLINE | ID: mdl-30271381

RESUMEN

Background: Protective effects of vitamin D have been reported in autoimmune and malignant thyroid diseases, though little is known about the underlying mechanism. Sirtuin 1 histon deacethylase (SIRT1) links the vitamin D pathway with regulation of transcription factor FOXO3a, a key player in cell cycle regulation and apoptosis. Aim of the present study was to investigate common single nucleotide polymorphisms (SNP's) in FOXO3a gene in respect to thyroid diseases, as well as to evaluate the hypothesis of Sirtuin1-FOXO3a interaction being a mediator of anti-proliferative vitamin D effects. Methods: The SNP's FOXO3a rs4946936/rs4945816/rs9400239 were genotyped in 257 patients with differentiated thyroid carcinoma (DTC), 139 patients with Hashimoto thyroiditis (HT) and 463 healthy controls (HC). Moreover, T-helper cells of HC and papillary thyroid cancer cell line BCPAP were incubated with 1,25(OH)2D3 and/or SIRT1 inhibitor Ex-527 in order to elucidate SIRT1- dependent vitamin D effects on cell proliferation and FOXO3a gene expression in vitro. Results: Patients with DTC tended to carry more often allele C in FOXO3a rs4946936 in comparison to HC (pcorrected = pc = 0.08). FOXO3a rs9400239T and rs4945816C was more frequent in HT in comparison to HC (pc = 0.02 and pc = 0.01, respectively). In both DTC and HT, we could not find a correlation of FOXO3a SNP's with vitamin D status. However, on in vitro level, 1,25(OH)2D3 showed an anti-proliferative effect in both T-helper cells and BCPAP, that was blocked by SIRT1 inhibition (T-helper cells: p = 0.0059, BCPAP: p = 0.04) and accompanied by elevated FOXO3a gene expression in T-helper cells (p = 0.05). Conclusions: FOXO3a rs9400239T and rs4945816C may constitute risk factors for HT, independent of the vitamin D status.This indicates the implication of FOXO3a in pathogenesis of autoimmune thyroid diseases. The dependency of anti-proliferative vitamin D effects on SIRT1 activity further suggests a key role of vitamin D-SIRT1-FOXO3a axis for protective vitamin D effects.

17.
Rev Med Inst Mex Seguro Soc ; 56(Suppl 1): S110-S119, 2018.
Artículo en Español | MEDLINE | ID: mdl-29638288

RESUMEN

The Research Unit in Gerontology at the Facultad de Estudios Superiores (FES) Zaragoza, from the Universidad Nacional Autónoma de México (UNAM), has developed a comprehensive model aimed at the promotion of healthy aging within the context of community development. The model is centered on the implementation of intensive educational programs addressed towards groups of older persons in what is known as "Gerontological Nuclei". Although it is true that there are satisfactory results, one limitation of the model is the difficulty of its implementation without supervision and university support. For this reason, two components have been included: resilience and generativity, which together could positively impact the model by strengthening contextual and personal components that are linked to healthy behavior. The approach of generativity and resilience are basic elements for the strengthening of human capacities during aging, since they can favor the autonomy, independence and decision-making capacity of people in the personal and community spheres. The article presents a model of healthy aging with possibilities of application at community level.


La Unidad de Investigación en Gerontología de la Facultad de Estudios Superiores (FES) Zaragoza, de la Universidad Nacional Autónoma de México (UNAM), ha desarrollado un modelo integral dirigido a la promoción del envejecimiento saludable en el contexto del desarrollo comunitario. El modelo se centra en la implementación de programas educativos intensivos que están dirigidos a grupos de personas mayores, en lo que se conoce como "núcleos gerontológicos". Si bien es cierto que existen resultados satisfactorios, una limitante del modelo es la dificultad para su implementación sin la supervisión y el apoyo universitario. Por tal motivo, se han incluido dos componentes: la resiliencia y la generatividad, los cuales en conjunto podrían impactar positivamente al modelo al fortalecer componentes contextuales y personales que se encuentran vinculados a un comportamiento saludable. El enfoque de la generatividad y la resiliencia constituyen elementos básicos para el fortalecimiento de las capacidades humanas durante el envejecimiento, ya que pueden favorecer la autonomía, la independencia y la capacidad de toma de decisiones de las personas en los ámbitos personal y comunitario. El artículo presenta un modelo de envejecimiento saludable con posibilidades de aplicación a nivel comunitario.


Asunto(s)
Participación de la Comunidad , Promoción de la Salud/métodos , Envejecimiento Saludable/psicología , Resiliencia Psicológica , Planificación Social , Anciano , Anciano de 80 o más Años , Envejecimiento Saludable/fisiología , Humanos , México
18.
Nutrition ; 49: 66-73, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29522979

RESUMEN

OBJECTIVES: On the basis of the immunomodulatory actions of vitamin D (VD), we investigated the effects of high-dose VD therapy over a 3 mo period on the immune response in patients with Addison's disease (AD). METHODS: This randomized, controlled, crossover trial included 13 patients with AD who received either cholecalciferol (4000 IU/d) for 3 mo followed by 3 mo placebo oil or the sequential alternative placebo followed by verum. Glucocorticoid replacement doses remained stable. The primary outcome measures were changes in 25-hydroxyvitamin D3 (25(OH)D3) levels and immune cells including T helper cells (Th; CD3+CD4+), late-activated Th cells (CD3+CD4+HLA-DR+), regulatory T cells (CD3+CD4+CD25brightCD127dim/neg), cytotoxic T cells (Tc; CD3+CD8+), late-activated Tc cells (CD3+CD8+HLA-DR+), and monocytes. The explorative analysis included the correlation of changes with VD-related gene polymorphisms and 21-hydroxylase antibody titers. RESULTS: Ten of 13 patients (77%) were VD deficient. Median 25(OH)D3 concentrations increased significantly to 41.5 ng/ml (median changes: 19.95 ng/ml; P = 0.0005) after 3 mo of cholecalciferol treatment. Within the T-cells, only the late-activated Th (median changes: 1.6%; P = 0.02) and late-activated Tc cells (median changes: 4.05%; P = 0.03) decreased, whereas monocytes (median changes: 1.05%; P = 0.008) increased after VD therapy. T-cell changes were associated with two polymorphisms (CYP27B1-rs108770012 and VDR-rs10735810), but no changes in the 21-hydroxylase antibody titers were observed. CONCLUSIONS: Three months of treatment with cholecalciferol achieved sufficient 25(OH)D3 levels and can regulate late-activated T-cells and monocytes in patients with AD. Explorative analysis revealed potential genetic contributions. This pilot trial provides novel insights about immunomodulation in AD.


Asunto(s)
Enfermedad de Addison/tratamiento farmacológico , Colecalciferol/administración & dosificación , Deficiencia de Vitamina D/tratamiento farmacológico , Vitaminas/administración & dosificación , Enfermedad de Addison/sangre , Enfermedad de Addison/complicaciones , Adulto , Calcifediol/sangre , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Proyectos Piloto , Linfocitos T Reguladores/efectos de los fármacos , Resultado del Tratamiento , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/etiología
19.
Int J Mol Sci ; 18(7)2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28714882

RESUMEN

Sphingolipids are characterized by a broad range of bioactive properties. Particularly, the development of insulin resistance, a major pathophysiological hallmark of Type 2 Diabetes mellitus (T2D), has been linked to ceramide signaling. Since vitamin D supplementation may slow down T2D progression by improving glucose concentrations and insulin sensitivity, we investigated whether vitamin D supplementation impacts on plasma sphingolipid levels in T2D patients. Thus, plasma samples of 59 patients with non-insulin-requiring T2D from a placebo-controlled, randomized, and double-blind study were retrospectively analyzed. Once per week, patients received either 20 drops of Vigantol oil, corresponding to a daily dose of 1904 IU/d vitamin D (verum: n = 31), or a placebo oil consisting of medium chain triglycerides (placebo: n = 28). Blood samples were taken from all of the participants at three different time points: 1) at the beginning of the study (baseline), 2) after 6 months supplementation, and 3) after an additional 6 months of follow-up. Plasma sphingolipids were measured by high-performance liquid chromatography tandem mass spectrometry. At baseline and 6 months follow-up, no significant differences in plasma sphingolipid species were detected between the placebo and verum groups. After 6 months, vitamin D supplementation significantly enhanced plasma C18dihydroceramide (dhCer; N-stearoyl-sphinganine (d18:0/18:0)) and C18ceramide (Cer; N-stearoyl-sphingosine (d18:1/18:0)) levels were observed in the verum group compared to the placebo group. This was accompanied by significantly higher 25-hydroxyvitamin D3 (25(OH)D3) blood levels in patients receiving vitamin D compared to the placebo group. Taken together, vitamin D supplementation induced changes of the C18 chain-length-specific dhCer and Cer plasma levels in patients with T2D. The regulation of sphingolipid signaling by vitamin D may thus unravel a novel mechanism by which vitamin D can influence glucose utilization and insulin action. Whether this acts favorably or unfavorably for the progression of T2D needs to be clarified.


Asunto(s)
Ceramidas/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Suplementos Dietéticos , Vitamina D/uso terapéutico , Femenino , Humanos , Lisofosfolípidos/sangre , Masculino , Persona de Mediana Edad , Esfingosina/análogos & derivados , Esfingosina/sangre
20.
Genes (Basel) ; 8(4)2017 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-28425954

RESUMEN

The etiology and pathophysiology of type 1 diabetes remain largely elusive with no established concepts for a causal therapy. Efforts to clarify genetic susceptibility and screening for environmental factors have identified the vitamin D system as a contributory pathway that is potentially correctable. This review aims at compiling all genetic studies addressing the vitamin D system in type 1 diabetes. Herein, association studies with case control cohorts are presented as well as family investigations with transmission tests, meta-analyses and intervention trials. Additionally, rare examples of inborn errors of vitamin D metabolism manifesting with type 1 diabetes and their immune status are discussed. We find a majority of association studies confirming a predisposing role for vitamin D receptor (VDR) polymorphisms and those of the vitamin D metabolism, particularly the CYP27B1 gene encoding the main enzyme for vitamin D activation. Associations, however, are tenuous in relation to the ethnic background of the studied populations. Intervention trials identify the specific requirements of adequate vitamin D doses to achieve vitamin D sufficiency. Preliminary evidence suggests that doses may need to be individualized in order to achieve target effects due to pharmacogenomic variation.

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