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1.
Toxics ; 12(6)2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38922089

RESUMEN

There is evidence to support the links between lead and cadmium exposure with hypertension and also with leukocyte telomere length (LTL). The objective of this study is to investigate the role that LTL may play in the relationship between lead and cadmium exposure and hypertension. This study consisted of 3718 participants from the National Health and Nutrition Examination Survey (NHANES) 1999-2002. Logistic regression was used to analyze the relationship between blood metals with hypertension, and the mediating model was used to evaluate the mediating effect of LTL. In the fully adjusted model, both blood lead and cadmium ln-transformed concentrations were significantly positively associated with hypertension risk, as were all quartiles of blood lead. Additionally, we observed positive linear dose-response relationships with hypertension by restricted cubic spline analysis (both p overall < 0.001, p non-linear = 0.3008 for lead and p non-linear = 0.7611 for cadmium). The ln-transformed blood lead and cadmium concentrations were associated with shorter LTL. LTL was inversely related to hypertension and the OR was 0.65 (95% CI: 0.47 to 0.89). Furthermore, LTL had mediating effects on the associations of blood lead and cadmium with hypertension risk, and the mediation proportions were 2.25% and 4.20%, respectively. Our findings suggested that exposure to lead and cadmium raised the risk of hypertension, while LTL played as a mediating factor.

2.
Toxics ; 12(5)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38787093

RESUMEN

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are associated with adverse health effects. This study examined the trend of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) levels in individuals with and without pre-existing comorbidities. We analyzed the characteristics of 13,887 participants across nine U.S. NHANES cycles (1999-2000 to 2017-2018) and calculated the geometric mean (GM) of PFOA and PFOS levels, standardized by sex and age. A joinpoint regression model was used to analyze the temporal trends of serum PFOA and PFOS levels. We observed declining PFOA and PFOS serum levels among adults in NHANES from 1999-2000 to 2017-2018. Serum PFOA and PFOS concentrations were higher in men, smokers, and individuals with pre-existing CKD, hyperlipidemia, CVD, and cancer. We observed faster decline rates in PFOA levels among individuals with diabetes and CKD and faster decline rates in PFOS levels among individuals with diabetes and those without CKD. This study provided evidence of varying levels and changing trends of PFOA and PFOS between groups with and without established chronic disease, highlighting the role of environmental chemicals in the onset and development of chronic diseases.

3.
BMC Psychiatry ; 24(1): 304, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654235

RESUMEN

BACKGROUND: Previous studies have reported associations between obstructive sleep apnea (OSA) and several mental disorders. However, further research is required to determine whether these associations are causal. Therefore, we evaluated the bidirectional causality between the genetic liability for OSA and nine mental disorders by using Mendelian randomization (MR). METHOD: We performed two-sample bidirectional MR of genetic variants for OSA and nine mental disorders. Summary statistics on OSA and the nine mental disorders were extracted from the FinnGen study and the Psychiatric Genomics Consortium. The primary analytical approach for estimating causal effects was the inverse-variance weighted (IVW), with the weighted median and MR Egger as complementary methods. The MR Egger intercept test, Cochran's Q test, Rucker's Q test, and the MR pleiotropy residual sum and outlier (MR-PRESSO) test were used for sensitivity analyses. RESULT: MR analyses showed that genetic liability for major depressive disorder (MDD) was associated with an increased risk of OSA (odds ratio [OR] per unit increase in the risk of MDD, 1.29; 95% CI, 1.11-1.49; P < 0.001). In addition, genetic liability for OSA may be associated with an increased risk of attention-deficit/hyperactivity disorder (ADHD) (OR = 1.26; 95% CI, 1.02-1.56; p = 0.032). There was no evidence that OSA is associated with other mental disorders. CONCLUSION: Our study indicated that genetic liability for MDD is associated with an increased risk of OSA without a bidirectional relationship. Additionally, there was suggestive evidence that genetic liability for OSA may have a causal effect on ADHD. These findings have implications for prevention and intervention strategies targeting OSA and ADHD. Further research is needed to investigate the biological mechanisms underlying our findings and the relationship between OSA and other mental disorders.


Asunto(s)
Trastorno Depresivo Mayor , Análisis de la Aleatorización Mendeliana , Apnea Obstructiva del Sueño , Humanos , Apnea Obstructiva del Sueño/genética , Trastorno Depresivo Mayor/genética , Trastorno Depresivo Mayor/epidemiología , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastornos Mentales/genética , Trastornos Mentales/epidemiología , Predisposición Genética a la Enfermedad/genética
4.
Front Public Health ; 12: 1303515, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38362209

RESUMEN

Background: Economic data on congenital heart disease are scarce in economically underdeveloped areas of China. Therefore, this study aimed to shed light on the level and changing trend of congenital heart disease inpatients' economic burden in underdeveloped areas. Method: This study used a multi-stage stratified cluster sampling method to select 11,055 inpatients with congenital heart disease from 197 medical and health institutions in Gansu Province. Their medical records and expenses were obtained from the Hospital Information System. Univariate analysis was conducted using the rank sum test and Spearman rank correlation. Quantile regression and random forest were used to analyze the influencing factors. Results: From 2015 to 2020, the average length of stay for congenital heart disease patients in Gansu Province was 10.09 days, with an average inpatient cost of USD 3,274.57. During this period, the average inpatient costs per time increased from USD 3,214.85 to USD 3,403.41, while the average daily inpatient costs increased from USD 330.05 to USD 376.56. The average out-of-pocket costs per time decreased from USD 2,305.96 to USD 754.77. The main factors that affected the inpatient costs included length of stay, cardiac procedure, proportion of medications, age, and hospital level. Conclusion: Congenital heart disease causes a significant economic burden on both families and society. Therefore, to further reduce the patient's financial burden, the length of stay should be reasonably reduced, and the rational distribution of medical resources should be continuously promoted to ensure equitable access to healthcare services.


Asunto(s)
Cardiopatías Congénitas , Hospitalización , Humanos , Pacientes Internos , Gastos en Salud , China/epidemiología , Cardiopatías Congénitas/epidemiología
5.
Org Biomol Chem ; 15(15): 3324-3336, 2017 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-28362016

RESUMEN

Several diketopiperazines have been shown to promote carbon-carbon coupling between benzene and aryl halides in the presence of potassium tert-butoxide and without the assistance of a transition metal catalyst. The structure of the diketopiperazine has an influence on its reductive potential and can help to promote the coupling of the more challenging aryl bromides with benzene.

6.
Molecules ; 20(2): 1755-74, 2015 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-25621421

RESUMEN

The coupling of haloarenes to styrenes and 1,1-diarylethenes has been achieved with potassium tert-butoxide in the presence of N,N'-dialkyldiketopiperazines. In contrast to previously reported reactions where phenanthroline has been used to mediate the reactions, the use of diketopiperazines can lead to either 1,1,2-triarylethenes or 1,1,2-triarylethanes, depending on the conditions used.


Asunto(s)
Compuestos de Bencidrilo/química , Dicetopiperazinas/química , Yodobencenos/química , Estilbenos/síntesis química , Estirenos/química , Butanoles/química , Catálisis , Concentración de Iones de Hidrógeno , Oxidación-Reducción
7.
J Am Chem Soc ; 136(51): 17818-26, 2014 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-25474411

RESUMEN

Coupling of haloarenes to arenes has been facilitated by a diverse range of organic additives in the presence of KO(t)Bu or NaO(t)Bu since the first report in 2008. Very recently, we showed that the reactivity of some of these additives (e.g., compounds 6 and 7) could be explained by the formation of organic electron donors in situ, but the role of other additives was not addressed. The simplest of these, alcohols, including 1,2-diols, 1,2-diamines, and amino acids are the most intriguing, and we now report experiments that support their roles as precursors of organic electron donors, underlining the importance of this mode of initiation in these coupling reactions.


Asunto(s)
Alcoholes/química , Aminoácidos/química , Diaminas/química , Halogenación , Hidrocarburos Aromáticos/química , Glicoles/química
8.
Beilstein J Org Chem ; 8: 994-1002, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23019427

RESUMEN

Neutral organic electron donors, featuring pyridinylidene-imidazolylidene, pyridinylidene-benzimidazolylidene and imidazolylidene-benzimidazolylidene linkages are reported. The pyridinylidene-benzimidazolylidene and imidazolylidene-benzimidazolylidene hybrid systems were designed to be the first super electron donors to convert iodoarenes to aryl radicals at room temperature, and indeed both show evidence for significant aryl radical formation at room temperature. The stronger pyridinylidene-imidazolylidene donor converts iodoarenes to aryl anions efficiently under appropriate conditions (3 equiv of donor). The presence of excess sodium hydride base has a very important and selective effect on some of these electron-transfer reactions, and a rationale for this is proposed.

9.
Chimia (Aarau) ; 66(6): 418-24, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22871286

RESUMEN

In the past decade, a host of exceptionally strong organic electron donors has been designed and prepared; their redox potentials are more negative than any previous neutral organic donors and extend beyond E(1/2) = -1 V vs. the saturated calomel electrode (SCE). Their ability to reduce a wide range of organic functional groups has been demonstrated and this article provides an overview of the main advances in the area and the guiding principles for the design of these reagents.


Asunto(s)
Electrones , Compuestos Orgánicos/química , Compuestos Orgánicos/síntesis química , Electrodos , Estructura Molecular , Oxidación-Reducción
11.
Org Biomol Chem ; 10(30): 5807-10, 2012 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-22395414

RESUMEN

The bis-pyridinylidene 13 converts aliphatic and aryl triflate esters to the corresponding alcohols and phenols respectively, using DMF as solvent, generally in excellent yields. While the deprotection of aryl triflates has been seen with other reagents and by more than one mechanism, the deprotection of alkyl triflates is a new reaction. Studies with (18)O labelled DMF indicate that the C-O bond stays intact and hence it is the S-O bond that cleaves, underlining that the cleavage results from the extraordinary electron donor capability of 13. Trifluoromethanesulfonamides are converted to the parent amines in like manner, representing the first cleavage of such substrates by a ground-state organic reducing reagent.

12.
J Am Chem Soc ; 132(44): 15462-4, 2010 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-20961105

RESUMEN

The first crown-tetracarbene complex of Ni(II) has been prepared, and its crystal structure determined. The complex can be reduced by Na/Hg, with an uptake of two electrons. The reduced complex reductively cleaves arenesulfonamides, including those derived from secondary aliphatic amines, and effects Birch reduction of anthracenes as well as reductive cleavage of stilbene oxides. Computational studies show that the orbital that receives electrons upon reduction of the complex 2 is predominantly based on the crown carbene ligand and also that the HOMO of the parent complex 2 is based on the ligand.

13.
J Am Chem Soc ; 131(49): 17980-5, 2009 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-19916499

RESUMEN

2-Dimethylalkylammonium pyridinium and 2-dimethylalkylammonium pyrimidinium ditriflate salts are very powerful methylating agents toward phosphorus (triphenylphosphine) and nitrogen (triethylamine) nucleophiles. In competition experiments with triethylamine as nucleophile, these N-methyl disalts are more reactive methylating agents than dimethyl sulfate. Reaction of the pyridinium dications with water as an oxygen nucleophile leads to attack at the 2-position of the heteroaromatic ring and displacement of an ammonium group; 2-hydroxypyridinium compounds are formed in the first instance, which are easily converted to 2-pyridones. Extending the scope of the reactions, a tricationic 2,6-bis(dimethylalkylammonium)pyridinium salt has also been prepared and characterized and its reactivity as a methylating agent assessed in comparison with that of the dications.


Asunto(s)
Amidinas/química , Cationes/química , Electroquímica , Estructura Molecular
14.
J Org Chem ; 74(22): 8713-8, 2009 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-19845372

RESUMEN

Neutral organic electron-donor 7, formally a pyridinylidene carbene dimer, effects reductive cleavage of C-O sigma-bonds in acyloin derivatives Ar(CO)CRR'OX (X = OAc, OPiv, OBz, OMs) and this represents the first cleavage of C-O sigma-bonds by a neutral organic electron-donor. The methodology is applicable to a large array of substrates and the reduced counterparts were isolated in good to excellent yields. For certain substrates, donor 7 behaves as a base, effecting condensation reactions with some acetate ester derivatives of acyloins, leading to butenolides. The variation in reactivity among the different substrates was rationalized.

15.
J Am Chem Soc ; 131(18): 6475-9, 2009 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-19415936

RESUMEN

Reaction of imidazolylidene-derived enetetramine 2 with aliphatic iodides and bromides (and with aryl iodides bearing alkene-containing side-chains in the ortho-position) leads to formation of aliphatic aldehydes through an unprecedented extrusion of a one-carbon unit from the enetetramine. An intermediate 2-alkylimidazoline 24 is proposed, where the alkyl group derives from the substrate; this imidazoline undergoes further reaction in situ to afford the observed aldehydes on acidic workup. Modified substrates were designed and prepared to probe the chemistry of the alkylimidazoline adducts and provided extensive information on the chemistry of the adducts.

16.
Org Lett ; 10(6): 1227-30, 2008 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-18288858

RESUMEN

Deprotonation of bispyridinium salt 7b affords bispyridinylidene 10, a very powerful neutral organic two-electron donor [E1/2 (DMF)=-1.13 V vs Ag/AgCl/KCl (sat)], presumably via the pyridinylidene 8. Donor 10 reduces aryl iodides and bromides to aryl anions in excellent yield and also reductively cleaves selected phenylalkylsulfones very efficiently.


Asunto(s)
Compuestos de Piridinio/química , Electroquímica , Electrones , Espectroscopía de Resonancia Magnética
20.
Bioorg Med Chem Lett ; 17(9): 2649-55, 2007 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17317171

RESUMEN

Chronic low-dose treatment of rats with the psychomimetic drug, phencyclidine, induces regionally specific metabolic and neurochemical changes in the CNS that mirror those observed in the brains of schizophrenic patients. Recent evidence suggests that drugs targeting serotoninergic and muscarinic receptors, and in particular 5-HT(7) antagonists and M(4) agonists, exert beneficial effects in this model of schizophrenia. Compounds that display this combined pattern of activity we refer to as serominic compounds. Based upon leads from natural product screening, we have designed and synthesised such serominic compounds, which are principally arylamidine derivatives of tetrahydroisoquinolines, and shown that they have the required serominic profile in ligand binding assays and show potential antipsychotic activity in functional assays.


Asunto(s)
Antipsicóticos/síntesis química , Antipsicóticos/farmacología , Química Farmacéutica/métodos , Agonistas Muscarínicos/síntesis química , Agonistas Muscarínicos/farmacología , Receptor Muscarínico M4/química , Esquizofrenia/tratamiento farmacológico , Anfetamina/farmacología , Animales , Antipsicóticos/química , Atropina/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Cinética , Conformación Molecular , Agonistas Muscarínicos/química , Ratas
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