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1.
Artículo en Inglés | MEDLINE | ID: mdl-38775726

RESUMEN

Oral contraceptive pills are used by approximately 250 million women worldwide, however a clear understanding of the concentrations of endogenous and exogenous hormones across a 28-day oral contraceptive pill pack is not well described. In our study of 16 female participants taking various monophasic oral contraceptive pills, we found significant fluctuations in endogenous and exogenous hormone levels throughout the pill cycle, challenging the previous assumption of hormonal stability in oral contraceptive users. The results from this study have wide ranging implications for research and treatment in women's health including: considerations in research design and interpretation for studies including women taking oral contraceptives, the potential for more precise and personalized methods of dosing to reduce unwanted side effects and adverse events, and the potential treatment of a variety of disorders ranging from musculoskeletal to neurological with exogenous hormones.

2.
Am J Respir Crit Care Med ; 207(11): 1515-1524, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36780644

RESUMEN

Rationale: Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by limited treatment options and high mortality. A better understanding of the molecular drivers of IPF progression is needed. Objectives: To identify and validate molecular determinants of IPF survival. Methods: A staged genome-wide association study was performed using paired genomic and survival data. Stage I cases were drawn from centers across the United States and Europe and stage II cases from Vanderbilt University. Cox proportional hazards regression was used to identify gene variants associated with differential transplantation-free survival (TFS). Stage I variants with nominal significance (P < 5 × 10-5) were advanced for stage II testing and meta-analyzed to identify those reaching genome-wide significance (P < 5 × 10-8). Downstream analyses were performed for genes and proteins associated with variants reaching genome-wide significance. Measurements and Main Results: After quality controls, 1,481 stage I cases and 397 stage II cases were included in the analysis. After filtering, 9,075,629 variants were tested in stage I, with 158 meeting advancement criteria. Four variants associated with TFS with consistent effect direction were identified in stage II, including one in an intron of PCSK6 (proprotein convertase subtilisin/kexin type 6) reaching genome-wide significance (hazard ratio, 4.11 [95% confidence interval, 2.54-6.67]; P = 9.45 × 10-9). PCSK6 protein was highly expressed in IPF lung parenchyma. PCSK6 lung staining intensity, peripheral blood gene expression, and plasma concentration were associated with reduced TFS. Conclusions: We identified four novel variants associated with IPF survival, including one in PCSK6 that reached genome-wide significance. Downstream analyses suggested that PCSK6 protein plays a potentially important role in IPF progression.


Asunto(s)
Estudio de Asociación del Genoma Completo , Fibrosis Pulmonar Idiopática , Humanos , Pulmón , Modelos de Riesgos Proporcionales , Europa (Continente) , Serina Endopeptidasas , Proproteína Convertasas
3.
Molecules ; 28(8)2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37110832

RESUMEN

The impacts on the morphological, electrical and hardness properties of thermoplastic polyurethane (TPU) plates using multi-walled carbon nanotubes (MWCNTs) as reinforcing fillers have been investigated, using MWCNT loadings between 1 and 7 wt%. Plates of the TPU/MWCNT nanocomposites were fabricated by compression molding from extruded pellets. An X-ray diffraction analysis showed that the incorporation of MWCNTs into the TPU polymer matrix increases the ordered range of the soft and hard segments. SEM images revealed that the fabrication route used here helped to obtain TPU/MWCNT nanocomposites with a uniform dispersion of the nanotubes inside the TPU matrix and promoted the creation of a conductive network that favors the electronic conduction of the composite. The potential of the impedance spectroscopy technique has been used to determine that the TPU/MWCNT plates exhibited two conduction mechanisms, percolation and tunneling conduction of electrons, and their conductivity values increase as the MWCNT loading increases. Finally, although the fabrication route induced a hardness reduction with respect to the pure TPU, the addition of MWCNT increased the Shore A hardness behavior of the TPU plates.

4.
Hum Mutat ; 43(12): 2010-2020, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36054330

RESUMEN

Most causal variants of Mendelian diseases are exonic. Whole-exome sequencing (WES) has become the diagnostic gold standard, but causative variant prioritization constitutes a bottleneck. Here we assessed an in-house sample-to-sequence pipeline and benchmarked free prioritization tools for germline causal variants from WES data. WES of 61 unselected patients with a known genetic disease cause was obtained. Variant prioritizations were performed by diverse tools and recorded to obtain a diagnostic yield when the causal variant was present in the first, fifth, and 10th top rankings. A fraction of causal variants was not captured by WES (8.2%) or did not pass the quality control criteria (13.1%). Most of the applications inspected were unavailable or had technical limitations, leaving nine tools for complete evaluation. Exomiser performed best in the top first rankings, while LIRICAL led in the top fifth rankings. Based on the more conservative top 10th rankings, Xrare had the highest diagnostic yield, followed by a three-way tie among Exomiser, LIRICAL, and PhenIX, then followed by AMELIE, TAPES, Phen-Gen,  AIVar, and VarNote-PAT. Xrare, Exomiser, LIRICAL, and PhenIX are the most efficient options for variant prioritization in real patient WES data.


Asunto(s)
Exoma , Mutación de Línea Germinal , Humanos , Secuenciación del Exoma , Exoma/genética
5.
Crit Care ; 26(1): 341, 2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36335405

RESUMEN

BACKGROUND: Sepsis is a severe systemic inflammatory response to infections that is accompanied by organ dysfunction and has a high mortality rate in adult intensive care units. Most genetic studies have identified gene variants associated with development and outcomes of sepsis focusing on biological candidates. We conducted the first genome-wide association study (GWAS) of 28-day survival in adult patients with sepsis. METHODS: This study was conducted in two stages. The first stage was performed on 687 European sepsis patients from the GEN-SEP network and 7.5 million imputed variants. Association testing was conducted with Cox regression models, adjusting by sex, age, and the main principal components of genetic variation. A second stage focusing on the prioritized genetic variants was performed on 2,063 ICU sepsis patients (1362 European Americans and 701 African-Americans) from the MESSI study. A meta-analysis of results from the two stages was conducted and significance was established at p < 5.0 × 10-8. Whole-blood transcriptomic, functional annotations, and sensitivity analyses were evaluated on the identified genes and variants. FINDINGS: We identified three independent low-frequency variants associated with reduced 28-day sepsis survival, including a missense variant in SAMD9 (hazard ratio [95% confidence interval] = 1.64 [1.37-6.78], p = 4.92 × 10-8). SAMD9 encodes a possible mediator of the inflammatory response to tissue injury. INTERPRETATION: We performed the first GWAS of 28-day sepsis survival and identified novel variants associated with reduced survival. Larger sample size studies are needed to better assess the genetic effects in sepsis survival and to validate the findings.


Asunto(s)
Estudio de Asociación del Genoma Completo , Sepsis , Adulto , Humanos , Estudio de Asociación del Genoma Completo/métodos , Población Blanca , Sepsis/genética , Negro o Afroamericano , Polimorfismo de Nucleótido Simple , Péptidos y Proteínas de Señalización Intracelular/genética
6.
J Pediatr Gastroenterol Nutr ; 74(2): 192-199, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34620762

RESUMEN

OBJECTIVES: Diagnosis of Wilson disease (WD) is difficult and, as early detection may prevent all symptoms, it is essential to know the exact prevalence to evaluate the cost-efficacy of a screening program. As the number of WD patients was high in our population, we wished to estimate prevalence by determining the carrier frequency for clinically relevant ATP7B mutations. METHODS: To estimate prevalence, screening for the most prevalent mutation was performed in 1661 individuals with ancestry in Gran Canaria, and the frequency of other mutations was estimated from patient records. Alternatively, ATP7B mutations were detected from exomes and genomes from 851 individuals with Canarian ancestry, 236 from Gran Canaria, and a public Spanish exome database. RESULTS: Estimated carrier frequencies in Gran Canaria ranged from 1 in 20 to 28, depending on the method used, resulting in prevalences of 1 case per 1547 to 3140 inhabitants. Alternatively, the estimated affected frequencies were 1 in 5985 to 7980 and 1 in 6278 to 16,510 in the archipelago or mainland Spain respectively. CONCLUSIONS: The number of carriers predicts much higher prevalences than reported, suggesting that WD is underdiagnosed; specific mutations may remain unnoticed due to low penetrance or no signs of disease at all; regional prevalence rather than national prevalence should be considered in cost-efficacy models to approach preventive screening in the asymptomatic population and genetic screening strategies will have to deal with the genetic heterogeneity of ATP7B in the general population and in patients.


Asunto(s)
Degeneración Hepatolenticular , ATPasas Transportadoras de Cobre/genética , Degeneración Hepatolenticular/diagnóstico , Degeneración Hepatolenticular/epidemiología , Degeneración Hepatolenticular/genética , Humanos , Mutación , Sistema de Registros , España
7.
Eur J Clin Pharmacol ; 78(3): 497-504, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34791521

RESUMEN

PURPOSE: To evaluate time trends in the prevalence of antithrombotic and statin use in four European countries. METHODS: Using population-based data from the United Kingdom, Denmark, Spain and Italy between 2010 and 2018, we calculated standardized annual prevalence proportions of antithrombotics and statin use, and changes in prevalence proportions (2018 vs. 2010). RESULTS: Prevalence proportion of statins increased from 24.8% to 24.6% (UK), 21.0% to 22.3% (Region of Southern Denmark [RSD]), 12.9% to 14.3% (Udine, Italy), and 20.3% to 23.2% (Spain). Prevalence proportions of antithrombotics declined in all four countries: 18.7% to 15.9% (UK; - 2.8% points), 18.9% to 18.1% (RSD; - 0.8% points), 17.7% to 16.6% (Udine; - 1.1% points) and 15.0% to 13.6% (Spain; - 1.4% points). These declines were driven by reductions in low-dose aspirin use: 15.3% to 8.9% (UK; - 6.4% points), 16.3% to 9.5% (RSD; - 6.8% points), 13.5% to 11.6% (Udine; - 1.9% points), and 10.2% to 8.8% (Spain; - 1.4% points). In the UK, low-dose aspirin use declined from 9.1% to 4.3% (- 4.8% points) for primary CVD prevention, and from 49.6% to 36.9% (- 12.7% points) for secondary prevention. Oral anticoagulant use gradually increased but did not fully account for the decrease in low-dose aspirin use. CONCLUSIONS: Antithrombotic use in the UK, RSD, Udine and Spain declined between 2010 and 2018, driven by a reduction in use of low-dose aspirin that is not completely explained by a gradual increase in OAC use. Use of statins remained constant in the UK, and increased gradually in the RSD, Udine and Spain.


Asunto(s)
Anticoagulantes/administración & dosificación , Utilización de Medicamentos/estadística & datos numéricos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Aspirina , Enfermedades Cardiovasculares/prevención & control , Relación Dosis-Respuesta a Droga , Europa (Continente) , Humanos
8.
Phys Chem Chem Phys ; 24(7): 4204-4211, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35119441

RESUMEN

Ultraviolet radiation (UVR) from the sun is essential for the prebiotic syntheses of nucleotides, but it can also induce photolesions such as the cyclobutane pyrimidine dimers (CPDs) to RNA or DNA oligonucleotide in prebiotic Earth. 2,6-Diaminopurine (26DAP) has been proposed to repair CPDs in high yield under prebiotic conditions and be a key component in enhancing the photostability of higher-order prebiotic DNA structures. However, its electronic relaxation pathways have not been studied, which is necessary to know whether 26DAP could have survived the intense UV fluxes of the prebiotic Earth. We investigate the electronic relaxation mechanism of both 26DAP and its 2'-deoxyribonucleoside (26DAP-d) in aqueous solution using steady-state and femtosecond transient absorption measurements that are complemented with electronic-structure calculations. The results demonstrate that both purine derivatives are significantly photostable to UVR. It is shown that upon excitation at 287 nm, the lowest energy 1ππ* state is initially populated. The population then branches following two relaxation coordinates in the 1ππ* potential energy surface, which are identified as the C2- and C6-relaxation coordinates. The population following the C6-coordinate internally converts to the ground state nonradiatively through a nearly barrierless conical intersection within 0.7 ps in 26DAP or within 1.1 ps in 26DAP-d. The population that follows the C2-relaxation coordinate decays back to the ground state by a combination of nonradiative internal conversion via a conical intersection and fluorescence emission from the 1ππ* minimum in 43 ps and 1.8 ns for the N9 and N7 tautomers of 26DAP, respectively, or in 70 ps for 26DAP-d. Fluorescence quantum yields of 0.037 and 0.008 are determined for 26DAP and 26DAP-d, respectively. Collectively, it is demonstrated that most of the excited state population in 26DAP and 26DAP-d decays back to the ground state via both nonradiative and radiative relaxation pathways. This result lends support to the idea that 26DAP could have accumulated in large enough quantities during the prebiotic era to participate in the formation of prebiotic RNA or DNA oligomers and act as a key component in the protection of the prebiotic genetic alphabet.


Asunto(s)
Dímeros de Pirimidina , Rayos Ultravioleta , 2-Aminopurina/análogos & derivados , Teoría Cuántica , Análisis Espectral
9.
Pharmacoepidemiol Drug Saf ; 31(11): 1182-1189, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35989512

RESUMEN

BACKGROUND: Reducing stroke occurrence requires the effective management of cardiovascular and other stroke risk factors. PURPOSE: To describe pre- and post-stroke medication use, focusing on antithrombotic therapy and mortality risk, in individuals hospitalised for ischaemic stroke (IS) in the United Kingdom. METHOD: Using primary care electronic health records from the United Kingdom, we identified patients hospitalised for IS (July 2016-September 2019) and classed them into three groups: atrial fibrillation (AF) diagnosed pre-stroke, AF diagnosed post-stroke, and non-AF stroke (no AF diagnosed pre-/post-stroke). We determined use of cardiovascular medications in the 90 days pre- and post-stroke and calculated mortality rates. RESULTS: There were 3201 hospitalised IS cases: 76.2% non-AF stroke, 15.7% AF pre-stroke, and 8.1% AF post-stroke. Oral anticoagulant (OAC) use increased between the pre- and post-stroke periods as follows: 54.3%-78.7% (AF pre-stroke group), 2.3%-84.8% (AF post-stroke group), and 3.4%-7.3% (non-AF stroke group). Corresponding increases in antiplatelet use were 30.8%-35.4% (AF pre-stroke group) 38.5%-47.5% (AF post-stroke group), and 37.5%-87.3% (non-AF stroke group). Among all IS cases, antihypertensive use increased from 66.8% pre-stroke to 78.8% post-stroke; statin use increased from 49.6%-85.2%. Mortality rates per 100 person-years (95% CI) were 17.30 (14.70-20.35) in the AF pre-stroke group and 9.65 (8.81-10.56) among all other stroke cases. CONCLUSION: Our findings identify areas for improvement in clinical practice, including optimising the level of OAC prescribing to patients with known AF, which could potentially help reduce the future burden of stroke.


Asunto(s)
Fibrilación Atrial , Isquemia Encefálica , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Administración Oral , Anticoagulantes/efectos adversos , Antihipertensivos/uso terapéutico , Fibrilación Atrial/complicaciones , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Isquemia Encefálica/complicaciones , Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/efectos adversos , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
10.
Int J Mol Sci ; 23(11)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35682862

RESUMEN

The transactive response DNA-binding protein (TARDBP/TDP-43) influences the processing of diverse transcripts, including that of histone deacetylase 6 (HDAC6). Here, we assessed TDP-43 activity in terms of regulating CD4+ T-cell permissivity to HIV-1 infection. We observed that overexpression of wt-TDP-43 increased both mRNA and protein levels of HDAC6, resulting in impaired HIV-1 infection independently of the viral envelope glycoprotein complex (Env) tropism. Consistently, using an HIV-1 Env-mediated cell-to-cell fusion model, the overexpression of TDP-43 levels negatively affected viral Env fusion capacity. Silencing of endogenous TDP-43 significantly decreased HDAC6 levels and increased the fusogenic and infection activities of the HIV-1 Env. Using pseudovirus bearing primary viral Envs from HIV-1 individuals, overexpression of wt-TDP-43 strongly reduced the infection activity of Envs from viremic non-progressors (VNP) and rapid progressors (RP) patients down to the levels of the inefficient HIV-1 Envs observed in long-term non-progressor elite controllers (LTNP-EC). On the contrary, silencing endogenous TDP-43 significantly favored the infectivity of primary Envs from VNP and RP individuals, and notably increased the infection of those from LTNP-EC. Taken together, our results indicate that TDP-43 shapes cell permissivity to HIV-1 infection, affecting viral Env fusion and infection capacities by altering the HDAC6 levels and associated tubulin-deacetylase anti-HIV-1 activity.


Asunto(s)
Infecciones por VIH , VIH-1 , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , VIH-1/fisiología , Histona Desacetilasa 6/genética , Humanos , Linfocitos T/metabolismo
11.
Molecules ; 27(4)2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35208973

RESUMEN

Cyanuric acid is a triazine derivative that has been identified from reactions performed under prebiotic conditions and has been proposed as a prospective precursor of ancestral RNA. For cyanuric acid to have played a key role during the prebiotic era, it would have needed to survive the harsh electromagnetic radiation conditions reaching the Earth's surface during prebiotic times (≥200 nm). Therefore, the photostability of cyanuric acid would have been crucial for its accumulation during the prebiotic era. To evaluate the putative photostability of cyanuric acid in water, in this contribution, we employed density functional theory (DFT) and its time-dependent variant (TD-DFT) including implicit and explicit solvent effects. The calculations predict that cyanuric acid has an absorption maximum at ca. 160 nm (7.73 eV), with the lowest-energy absorption band extending to ca. 200 nm in an aqueous solution and exhibiting negligible absorption at longer wavelengths. Excitation of cyanuric acid at 160 nm or longer wavelengths leads to the population of S5,6 singlet states, which have ππ* character and large oscillator strengths (0.8). The population reaching the S5,6 states is expected to internally convert to the S1,2 states in an ultrafast time scale. The S1,2 states, which have nπ* character, are predicted to access a conical intersection with the ground state in a nearly barrierless fashion (ca. ≤ 0.13 eV), thus efficiently returning the population to the ground state. Furthermore, based on calculated spin-orbit coupling elements of ca. 6 to 8 cm-1, the calculations predict that intersystem crossing to the triplet manifold should play a minor role in the electronic relaxation of cyanuric acid. We have also calculated the vertical ionization energy of cyanuric acid at 8.2 eV, which predicts that direct one-photon ionization of cyanuric acid should occur at ca. 150 nm. Collectively, the quantum-chemical calculations predict that cyanuric acid would have been highly photostable under the solar radiation conditions reaching the Earth's surface during the prebiotic era in an aqueous solution. Of relevance to the chemical origin of life and RNA-first theories, these observations lend support to the idea that cyanuric acid could have accumulated in large quantities during the prebiotic era and thus strengthens its candidature as a relevant prebiotic nucleobase.


Asunto(s)
Modelos Químicos , Procesos Fotoquímicos , Triazinas/química , Estabilidad de Medicamentos
12.
J Am Chem Soc ; 143(7): 2676-2681, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33587618

RESUMEN

Heavy-atom-free photosensitizers (HAF-PSs) based on thionation of carbonyl groups of readily accessible organic compounds are rapidly emerging as a versatile class of molecules. However, their photochemical properties and electronic relaxation mechanisms are currently unknown. Investigating the excited-state dynamics is essential to understand their benefits and limitations and to develop photosensitizers with improved photochemical properties. Herein, the photochemical and electronic-structure properties of two of the most promising HAF-PSs developed to date are revealed. It is shown that excitation of thio-4-(dimethylamino)naphthalamide and thionated Nile Red with near-infrared radiation leads to the efficient population of the triplet manifold through multiple relaxation pathways in hundreds of femtoseconds. The strong singlet-triplet couplings in this family of photosensitizers should enable a broad range of applications, including in photodynamic therapy, photocatalysis, photovoltaics, organic LEDs, and photon up-conversion.


Asunto(s)
Rayos Infrarrojos , Fármacos Fotosensibilizantes/química , Oxígeno Singlete/metabolismo , Humanos , Neoplasias/tratamiento farmacológico , Oxazinas/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Teoría Cuántica , Oxígeno Singlete/química , Compuestos de Sulfhidrilo/química
13.
J Gen Intern Med ; 36(9): 2648-2655, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33501527

RESUMEN

BACKGROUND: Many adults have risk factors for non-alcoholic fatty liver disease (NAFLD). Screening all adults with risk factors for NAFLD using imaging is not feasible. OBJECTIVE: To develop a practical scoring tool for predicting NAFLD using participant demographics, medical history, anthropometrics, and lab values. DESIGN: Cross-sectional. PARTICIPANTS: Data came from 6194 white, African American, Hispanic, and Chinese American participants from the Multi-Ethnic Study of Atherosclerosis cohort, ages 45-85 years. MAIN MEASURES: NAFLD was identified by liver computed tomography (≤ 40 Hounsfield units indicating > 30% hepatic steatosis) and data on 14 predictors was assessed for predicting NAFLD. Random forest variable importance was used to identify the minimum subset of variables required to achieve the highest predictive power. This subset was used to derive (n = 4132) and validate (n = 2063) a logistic regression-based score (NAFLD-MESA Index). A second NAFLD-Clinical Index excluding laboratory predictors was also developed. KEY RESULTS: NAFLD prevalence was 6.2%. The model included eight predictors: age, sex, race/ethnicity, type 2 diabetes, smoking history, body mass index, gamma-glutamyltransferase (GGT), and triglycerides (TG). The NAFLD-Clinical Index model excluded GGT and TG. In the NAFLD-MESA model, the derivation set achieved an AUCNAFLD-MESA = 0.83 (95% CI, 0.81 to 0.86), and the validation set an AUCNAFLD-MESA = 0.80 (0.77 to 0.84). The NAFLD-Clinical Index model was AUCClinical = 0.78 [0.75 to 0.81] in the derivation set and AUCClinical = 0.76 [0.72 to 0.80] in the validation set (pBonferroni-adjusted < 0.01). CONCLUSIONS: The two models are simple but highly predictive tools that can aid clinicians to identify individuals at high NAFLD risk who could benefit from imaging.


Asunto(s)
Aterosclerosis , Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Adulto , Anciano , Anciano de 80 o más Años , Asiático , Estudios Transversales , Humanos , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/epidemiología
14.
Phys Chem Chem Phys ; 23(44): 25048-25055, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34730146

RESUMEN

Site-selected sulfur-substituted nucleobases are a class of all organic, heavy-atom-free photosensitizers for photodynamic therapy applications that exhibit excellent photophysical properties such as strong absorption in the ultraviolet-A region of the electromagnetic spectrum, near-unity triplet yields, and a high yield of singlet oxygen generation. Recent investigations on doubly thionated nucleobases, 2,4-dithiothymine, 2,4-dithiouracil, and 2,6-dithiopurine, demonstrated that these set of dithionated nucleobases outperform the photodynamic efficacy exhibit by 4-thiothymidine-the most widely studied singly substituted thiobase to date. Out of the three dithionated nucleobases, 2,6-dithiopurine was shown to be the most effective, exhibiting inhibition of cell proliferation of up to 63% when combined with a low UVA dose of 5 J cm-2. In this study, we elucidated the electronic relaxation pathways leading to the population of the reactive triplet state of 2,6-dithiopurine. 2,6-Dithiopurine populates the triplet manifold in less than 150 fs, reaching the nπ* triplet state minimum within a lifetime of 280 ± 50 fs. Subsequently, the population in the nπ* triplet state minimum internally converts to the long-lived ππ* triplet state within a lifetime of 3 ± 1 ps. The relatively slow internal conversion lifetime is associated with major conformational relaxation in going from the nπ* to ππ* triplet state minimum. A unity triplet yield of 1.0 ± 0.1 is measured.


Asunto(s)
Antineoplásicos/farmacología , Fármacos Fotosensibilizantes/farmacología , Purinas/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Fotoquimioterapia , Fármacos Fotosensibilizantes/química , Purinas/química , Neoplasias Cutáneas/patología , Factores de Tiempo , Rayos Ultravioleta
15.
Pharmacoepidemiol Drug Saf ; 30(2): 229-236, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33009708

RESUMEN

PURPOSE: To describe the effect that validation of venous thromboembolism (VTE) coded entries in the health improvement network (THIN) has on incidence rates of VTE among a cohort of rivaroxaban/warfarin users. METHODS: Among 36 701 individuals with a first prescription for rivaroxaban/warfarin between 2012 and 2015, we performed a two-step VTE case identification process followed by a two-step case validation process involving manual review of patient records. A valid case required a coded entry for VTE at some point after their first rivaroxaban/warfarin prescription with evidence of referral/hospitalization either as a coded entry or entered as free text. Positive predictive values (PPVs) with 95% confidence intervals (CIs) were calculated using validated cases as the gold standard. Incidence rates were calculated per 1000 person-years with 95% CIs. RESULTS: We identified 2166 patients with a coded entry of VTE after their initial rivaroxaban/warfarin prescription; incidence rate of 45.31 per 1000 person-years (95% CI: 43.49-47.22). After manual review of patient records including the free text, there were 712 incident VTE cases; incidence rate of 14.90 per 1000 person-years (95% CI: 13.85-16.02). The PPV for coded entries of VTE alone was 32.9%, and the PPV for coded entries of VTE with a coded entry of referral/hospitalization was 39.8%; this increased to 69.6% after manual review of coded clinical entries in patient records. CONCLUSIONS: Among rivaroxaban/warfarin users in THIN, valid VTE case identification requires manual review of patient records including the free text to prevent outcome misclassification and substantial overestimation of VTE incidence rates.


Asunto(s)
Rivaroxabán , Tromboembolia Venosa , Anticoagulantes/efectos adversos , Inhibidores del Factor Xa/efectos adversos , Humanos , Rivaroxabán/efectos adversos , Tromboembolia Venosa/inducido químicamente , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiología , Warfarina/efectos adversos
16.
Sensors (Basel) ; 21(16)2021 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-34450959

RESUMEN

One of the biggest challenges associated with vibration energy harvesters is their limited bandwidth, which reduces their effectiveness when utilized for Internet of Things applications. This paper presents a novel method of increasing the bandwidth of a cantilever beam by using an embedded transverse out-of-plane movable mass, which continuously changes the resonant frequency due to mass change and non-linear dynamic impact forces. The concept was investigated through experimentation of a movable mass, in the form of a solid sphere, that was embedded within a stationary proof mass with hollow cylindrical chambers. As the cantilever oscillated, it caused the movable mass to move out-of-plane, thus effectively altering the overall effective mass of the system during operation. This concept combined high bandwidth non-linear dynamics from the movable mass with the high power linear dynamics from the stationary proof mass. This paper experimentally investigated the frequency and power effects of acceleration, the amount of movable mass, the density of the mass, and the size of the movable mass. The results demonstrated that the bandwidth can be significantly increased from 1.5 Hz to >40 Hz with a transverse movable mass, while maintaining high power output. Dense movable masses are better for high acceleration, low frequency applications, whereas lower density masses are better for low acceleration applications.

17.
Int J Cancer ; 147(9): 2394-2404, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32329063

RESUMEN

There is increasing interest regarding potential protective effects of low-dose aspirin against various gastrointestinal cancers. We aimed to quantify the association between use of low-dose aspirin and risk of gastric/oesophageal cancer using a population-based primary care database in the UK. Between January 2005 and December 2015, we identified a cohort of 223 640 new users of low-dose aspirin (75-300 mg/day) and a matched cohort of nonusers at the start of follow-up from The Health Improvement Network. Cohorts were followed to identify incident cases of gastric/oesophageal cancer. Nested case-control analyses were conducted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for current vs nonuse of low-dose aspirin using logistic regression. Current use was defined as when low-dose aspirin lasted 0 to 90 days before the index date (event date for cases, random date for controls) and previous duration was ≥1 year. We identified 727 incident cases of gastric cancer and 1394 incident cases of oesophageal cancer. ORs (95% CIs) were 0.46 (0.38-0.57) for gastric cancer and 0.59 (0.51-0.69) for oesophageal cancer. The effect remained consistent with no clear change seen between previous duration of low-dose aspirin use of 1-3, 3-5 or >5 years. The reduced risks was seen with 75 mg/day, and effects were consistent in lag-time analyses. In conclusion, our results indicate that use of low-dose aspirin is associated with a 54% reduced risk of gastric cancer and a 41% reduced risk of oesophageal cancer as supported by mechanistic data.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Aspirina/administración & dosificación , Neoplasias Esofágicas/epidemiología , Atención Primaria de Salud/estadística & datos numéricos , Neoplasias Gástricas/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Bases de Datos Factuales/estadística & datos numéricos , Relación Dosis-Respuesta a Droga , Neoplasias Esofágicas/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Neoplasias Gástricas/prevención & control , Reino Unido/epidemiología
18.
Cancer Causes Control ; 31(5): 517-524, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32146553

RESUMEN

PURPOSE: We investigated whether the relationship between diabetes and all-cause and CVD-related mortality differed between women with and without breast cancer among a cohort drawn from the same source population. METHODS: We interviewed 1,363 women newly diagnosed with breast cancer in 1996-1997, and 1,358 age-matched women without breast cancer, to assess history of physician-diagnosed diabetes. All-cause (n = 631) and CVD-specific mortality (n = 234) was determined by the National Death Index through 2009. We estimated multivariable-adjusted hazard ratios (HRs) for the rates of all-cause and CVD-specific mortality and, to account for competing causes of death, and subdistribution HRs (sHRs) for risk of CVD-related death. RESULTS: Among women with and without breast cancer, respectively, diabetes was associated with: all-cause mortality [HR (95% CI) 1.52 (1.13, 2.05) and 2.17 (1.46, 3.22)]; CVD-specific deaths [1.74 (1.06, 2.84) and 2.06 (1.11, 3.84)]; and risk of CVD-related death [sHR 1.36 (0.81, 2.27) and 1.79 (0.94, 3.40)]. Differences in effect estimates between women with and without breast cancer did not reach statistical significance (p-interaction > 0.10). CONCLUSION: We found that the positive association between a history of physician-diagnosed diabetes and risk of all-cause and CVD-related mortality is of similar magnitude among a population-based cohort of women with or without breast cancer.


Asunto(s)
Neoplasias de la Mama/epidemiología , Enfermedades Cardiovasculares/epidemiología , Diabetes Mellitus/epidemiología , Adulto , Anciano , Neoplasias de la Mama/mortalidad , Enfermedades Cardiovasculares/mortalidad , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Modelos de Riesgos Proporcionales
19.
J Nutr ; 150(6): 1509-1515, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32133497

RESUMEN

BACKGROUND: Diet quality is an important risk factor for type 2 diabetes (T2D) and cardiovascular disease (CVD). Little is known about the diet quality of South Asians in the United States, a group with higher rates of T2D and CVD compared with other racial/ethnic groups. OBJECTIVE: This study determined whether diet quality differs between South Asian adults in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study and whites, Chinese Americans, African Americans, and Hispanics in the Multi-Ethnic Study of Atherosclerosis (MESA). METHODS: Cross-sectional data from 3926 participants free of CVD from MESA visit 5 (2010-2011) and 889 South Asian participants from MASALA visit 1 (2010-2013) were pooled. Diet quality was assessed using the Alternative Healthy Eating Index (AHEI-2010) derived using FFQs. Multivariable linear regression models adjusted for age, sex, and total energy intake were used to compare mean differences in diet quality between the racial/ethnic groups. RESULTS: MESA participants were, on average, 14 y older than MASALA participants. The adjusted mean (95% CI) scores for the AHEI-2010 were 70.2 (69.5, 70.9) among South Asians, 66.2 (66.3, 68.2) among Chinese Americans, 61.1 (60.7, 61.6) among whites, 59.0 (58.4, 59.7) among Hispanics, and 57.5 (56.9, 58.1) among African Americans. The mean AHEI scores among South Asians were 3.1 (1.8, 4.3), 9.2 (8.3, 10.1), 11.2 (10.2, 12.3), and 12.8 (11.8, 13.7) points higher compared with Chinese Americans, whites, Hispanics, and African Americans, respectively. CONCLUSIONS: South Asian adults in the United States have a higher diet quality compared with other racial/ethnic groups. This paradoxical finding is not consistent with the observed higher rates of T2D and CVD compared with other groups. This is further evidence of the importance of studying the South Asian population to better understand the causes of chronic disease not explained by diet quality.


Asunto(s)
Aterosclerosis/etnología , Dieta , Anciano , Asia/etnología , Estudios Transversales , Registros de Dieta , Emigración e Inmigración , Etnicidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos
20.
Bioorg Med Chem ; 28(20): 115700, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33069076

RESUMEN

The aggregation of ß-amyloid peptides is associated to neurodegeneration in Alzheimer's disease (AD) patients. Consequently, the inhibition of both oligomerization and fibrillation of ß-amyloid peptides is considered a plausible therapeutic approach for AD. Herein, the synthesis of new naphthalene derivatives and their evaluation as anti-ß-amyloidogenic agents are presented. Molecular dynamic simulations predicted the formation of thermodynamically stable complexes between the compounds, the Aß1-42 peptide and fibrils. In human microglia cells, these compounds inhibited the aggregation of Aß1-42 peptide. The lead compound 8 showed a high affinity to amyloid plaques in mice brain ex vivo assays and an adequate log Poct/PBS value. Compound 8 also improved the cognitive function and decreased hippocampal ß-amyloid burden in the brain of 3xTg-AD female mice. Altogether, our results suggest that 8 could be a novel therapeutic agent for AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Naftalenos/farmacología , Fármacos Neuroprotectores/farmacología , Fragmentos de Péptidos/antagonistas & inhibidores , Agregado de Proteínas/efectos de los fármacos , Agregación Patológica de Proteínas/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Relación Dosis-Respuesta a Droga , Ratones , Ratones Endogámicos C57BL , Simulación de Dinámica Molecular , Estructura Molecular , Naftalenos/síntesis química , Naftalenos/química , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Fragmentos de Péptidos/metabolismo , Agregación Patológica de Proteínas/metabolismo , Relación Estructura-Actividad , Termodinámica
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