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1.
Sports Med ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39218828

RESUMO

BACKGROUND: Different types of sedentary behavior are associated with several health outcomes, but the causality of these associations remains unclear. OBJECTIVES: To conduct a systematic review and meta-analysis of Mendelian randomization (MR) studies investigating the associations between sedentary behaviors and health outcomes. METHODS: A systematic search on PubMed, Embase, Web of Science, Scopus, and PsycINFO up to August 2023 was conducted to identify eligible MR studies. We selected studies that assessed associations of genetically determined sedentary behaviors and health outcomes. A meta-analysis was conducted to examine the causal associations when two or more MR studies were available. We graded the evidence level of each MR association based on the results of the main method and sensitivity analyses in MR studies. RESULTS: A total of 31 studies with 168 MR associations between six types of sedentary behavior and 47 health outcomes were included. Results from meta-analyses suggested a total of 47 significant causal associations between sedentary behaviors and health outcomes. Notably, more leisure TV watching is robustly correlated with increased risks of myocardial infarction, coronary artery disease, all-cause ischemic stroke, and type 2 diabetes. Conversely, robust inverse associations were observed between leisure computer use and risks of rheumatoid arthritis, Alzheimer's disease, and gastroesophageal reflux disease. CONCLUSION: These findings suggest that different types of sedentary behavior have distinct causal effects on health outcomes. Therefore, interventions should focus not only on reducing sedentary time but also on promoting healthier types of sedentary behavior. PROSPERO REGISTRATION: CRD42023453828.

3.
Food Funct ; 15(16): 8248-8257, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39076035

RESUMO

Background: Non-alcoholic fatty liver disease (NAFLD) has emerged as a leading cause of several chronic diseases, imposing a significant global economic burden. The Mediterranean diet (MD) and low-fat diet (LFD) are the two primary recommended dietary patterns that exhibit distinct positive effects on treating NAFLD. Objective: To investigate which of the two diets, MD and LFD, is more effective in the treatment of NAFLD. Methods: Randomized controlled trials (RCTs) up to April 2024 were searched for in PubMed, Web of Science, Medline, Scopus and Embase. Interventions included MD or LFD, with primary outcome measures being intrahepatic lipid, liver stiffness, triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, gamma-glutamyl transferase, and homeostasis model assessment of insulin resistance. Secondary outcomes included weight, waist circumference, and body mass index. Use of random effects meta-analysis to assess outcomes of interest. Results: meta-analysis revealed no significant differences between MD and LFD in improving liver enzymes, liver fat, and related indices in NAFLD patients. Our findings provide compelling evidence for patients and healthcare professionals, allowing patients to choose a dietary pattern that aligns with their preferences and disease conditions. In summary, both MD and LFD can equivalently ameliorate NAFLD in the short term. Conclusions: Our results show that MD and LFD have similar therapeutic effects on liver enzymes and liver fat content in patients with NAFLD in the short term. Furthermore, our meta-analysis results have also opened up a new avenue of thought as to whether similar effects are achieved by alternating MD and LFD on alternate days.


Assuntos
Dieta com Restrição de Gorduras , Dieta Mediterrânea , Fígado , Hepatopatia Gordurosa não Alcoólica , Ensaios Clínicos Controlados Aleatórios como Assunto , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Humanos , Fígado/metabolismo , Masculino , Alanina Transaminase/metabolismo , Feminino , Triglicerídeos/metabolismo , Adulto
4.
Front Public Health ; 12: 1351972, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774055

RESUMO

Twenty-four-hour movement behaviors have significant implications for physical and mental health throughout one's lifespan. Consistent with movement behaviors, several countries have formulated and published 24-h movement guidelines. This review summarized the studies related to 24-h movement guidelines among children and adolescents from six databases (MEDLINE, EMBASE, PubMed, Web of Science, CINAHL, and SPORTDiscus). In a total of 61 studies that discussed compliance with 24-h movement guidelines, the overall adherence rate was very low (7.1%), with boys exceeding girls, children surpassing adolescents, and regional differences. A total of 39 studies examined the associations between 24-h movement guidelines and health indicators. Findings indicated that meeting all three guidelines was favorably associated with adiposity, cardiometabolic health, mental and social health, physical fitness, health-related quality of life, academic achievement, cognitive development, perceived health, dietary patterns, and myopia. Future research should utilize longitudinal and experimental designs to enhance our understanding of the associations between 24-h movement guidelines and health indicators, thereby aiding the formulation and refinement of such guidelines. Systematic review registration: https://www.crd.york.ac.uk/prospero/, CRD42023481230.


Assuntos
Exercício Físico , Humanos , Adolescente , Criança , Pré-Escolar , Feminino , Masculino , Qualidade de Vida
5.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38675462

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is usually associated with obesity. However, it is crucial to recognize that NAFLD can also occur in lean individuals, which is frequently overlooked. Without an approved pharmacological therapy for lean NAFLD, we aimed to investigate whether the Ganjianglingzhu (GJLZ) decoction, a representative traditional Chinese medicine (TCM), protects against lean NAFLD and explore the potential mechanism underlying these protective effects. The mouse model of lean NAFLD was established with a methionine-choline-deficient (MCD) diet in male C57BL/6 mice to be compared with the control group fed the methionine-choline-sufficient (MCS) diet. After four weeks, physiological saline, a low dose of GJLZ decoction (GL), or a high dose of GJLZ decoction (GH) was administered daily by gavage to the MCD group; the MCS group was given physiological saline by gavage. Untargeted metabolomics techniques were used to explore further the potential mechanism of the effects of GJLZ on lean NAFLD. Different doses of GJLZ decoction were able to ameliorate steatosis, inflammation, fibrosis, and oxidative stress in the liver; GL performed a better effect on lean NAFLD. In addition, 78 candidate differential metabolites were screened and identified. Combined with metabolite pathway enrichment analysis, GL was capable of regulating the glucose and lipid metabolite pathway in lean NAFLD and regulating the glycerophospholipid metabolism by altering the levels of sn-3-O-(geranylgeranyl)glycerol 1-phosphate and lysoPC(P-18:0/0:0). GJLZ may protect against the development of lean NAFLD by regulating glucose and lipid metabolism, inhibiting the levels of sn-3-O-(geranylgeranyl)glycerol 1-phosphate and lysoPC(P-18:0/0:0) in glycerophospholipid metabolism.

6.
Front Cardiovasc Med ; 10: 1156123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37408651

RESUMO

Pre-obesity, as a significant risk factor for the progression of metabolic syndrome (MS), has become a prevalent public health threat globally. In this three-year longitudinal study of pre-obese women at baseline, the goal was to clarify the female-specific bidirectional relationship between the risk of MS and blood alanine aminotransferase. In this manuscript, the MS score was determined using the following equation: MS score = 2*waist/height + fasting glucose/5.6 + TG/1.7 + SBP/130-HDL/1.02 for men and 1.28 for women, which is highly related to the risk of MS. With 2,338 participants, a hierarchical nonlinear model with random effects was utilized to analyze the temporal trends of serum characteristics from 2017 to 2019. A bivariate cross-lagged panel model (CLPM) was employed to estimate the structural relations of frequently measured variables at three different time points to determine the directionality of the relationship between the risk of MS and serum characteristics. MassARRAY Analyzer 4 platforms were used to evaluate and genotype candidate SNPs. In this study, the MS score only rose with age in females; it was positively correlated with serum alanine aminotransferase (ALT) in females; the CLPM revealed that the MS score in 2017 predicted ALT in 2018 (ß = 0.066, p < 0.001); and ALT in 2018 predicted an MS score in 2019 (ß = 0.037, p < 0.050); both relationships were seen in females. Additionally, the MS score in elderly females with NAFLD was related to the rs295 in the lipoprotein lipase (LPL) gene (p = 0.042). Our work showed that there may be female-specific causal correlations between elevated ALT and risk of MS and that the polymorphism rs295 in LPL may serve as a marker for the prognosis of MS. The genetic roles of rs295 in the LPL gene in the onset of MS and the development of ALT in the elderly Chinese Han population are thus provided by this, offering one potential mechanism.

7.
Angew Chem Int Ed Engl ; 54(19): 5583-7, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25784624

RESUMO

The tape-like chain {[(tptz)Mn(II) (H2 O)Mn(III) (CN)6 ]2 Mn(II) (H2 O)2 }n ⋅4n MeOH⋅2n H2 O based on the anisotropic building block hexacyanomanganate(III) exhibits long-range magnetic ordering below 5.1 K as well as single-chain magnetic behavior at lower temperatures with an effective energy barrier of 40.5(7) K.

8.
Angew Chem Int Ed Engl ; 53(43): 11567-70, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25213266

RESUMO

The self-assembly of organic TCNQF˙⁻ radicals (2-fluoro-7,7,8,8-tetracyano-p-quinodimethane) and the anisotropic [Tb(valpn)Cu](3+) dinuclear cations produced a single-chain magnet (SCM) involving stacking interactions of TCNQF˙⁻ radicals (H2valpn is the Schiff base from the condensation of o-vanillin with 1,3-diaminopropane). Static and dynamic magnetic characterizations reveal that the effective energy barrier for the reversal of the magnetization in this hetero-tri-spin SCM is significantly larger than the barrier of the isolated single-molecule magnet based on the {TbCu} dinuclear core.

9.
Dalton Trans ; 43(18): 6802-10, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24647575

RESUMO

Treatment of [Mn(dpop)(H2O)2]Cl2 (dpop = 2,13-dimethyl-3,6,9,12,18-pentaazabicyclo-[12.3.1]octadeca-1(18),2,12,14,16-pentaene) with K4[Mo(CN)7]·2H2O under varied synthetic conditions afforded four different compounds: {[Mn(dpop)]4[(dpop)Mn(H2O)]2[Mo(III)(CN)7]3·27H2O}n (1), {[(dpop)Mn(H2O)][Mo(III)(CN)7][Mn(dpop)]3[Mo(IV)(CN)8]·29H2O}n (2), {[(dpop)Mn(H2O)]2[Mo(IV)(CN)8]2[Mn(dpop)]4[Mo(III)(CN)7]·12H2O}n (3), and [(dpop)Mn(H2O)]2[Mo(IV)(CN)8]·9H2O (4). Compound 1 contains only [Mo(III)(CN)7](4-) anions and exhibits a corrugated two-dimensional layered architecture. The structure of 2 with a 1 : 1 ratio of Mo(III) : Mo(IV) is best described as a ladder-like chain composed of [Mo(III)(CN)7](4-)-based pentanuclear [Mo(III)Mn(II)4] fragments which are further linked by in situ produced [Mo(IV)(CN)8](4-) anions. In the case of 3, [Mn8Mo8] rings containing bent [Mo(III)Mn(II)2] fragments are extended into a two-dimensional layer with the ratio of [Mo(CN)7](4-) : [Mo(CN)8](4-) being 1 : 2. Compound 4 exhibits a bent trinuclear structure in which two CN(-) groups of [Mo(CN)8](4-) function as µ2-bridges to [Mn(dpop)(H2O)](2+) fragments. Magnetic studies suggest significant antiferromagnetic coupling interactions occur between Mo(III) and Mn(II) ions while, not surprisingly, interactions between the Mn(ii) ions through diamagnetic [Mo(IV)(CN)8](4-) anions are negligible. Compound 1 exhibits ferrimagnetic ordering below 3.0 K whereas 2 shows the signature of single molecule magnet behavior with slow relaxation of the magnetization and an effective energy barrier (U(eff)) of 8.1 K.

10.
Chem Commun (Camb) ; 50(12): 1429-31, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24346307

RESUMO

The 3-D coordination polymer with the basic formula Cd2(TCNQ)3.5(H2O)2 is the first instance of the coexistence of the bridging modes µ2, µ3 and µ4 for TCNQ in one network. Single crystal measurements revealed the compound to be a good semiconductor with a room temperature conductivity of 5.8 × 10(-3) S cm(-1).

11.
Dalton Trans ; 42(41): 14685-8, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24026666

RESUMO

The mononuclear ferric compound Fe(H-5-Cl-thsa-Me)(5-Cl-thsa-Me)·H2O () was synthesized and characterized using powder/single-crystal X-ray diffraction, Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic susceptibility measurements. This photo-responsive compound shows reversible, two-step spin-crossover behaviour. Moreover, dielectric anomalies were observed during the spin transitions, demonstrating the multifunctional properties of compound .

12.
Dalton Trans ; 42(41): 14693-701, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23943045

RESUMO

A series of isostructural octanuclear lanthanide complexes of general formula [Ln8(sao)4(µ3-OH)4(NO3)12(DMF)12] (Ln = Nd (), Sm (), Eu (), Gd (), Tb (), Dy (), Ho (), Er (); DMF = dimethylformamide) have been prepared via reactions of salicylaldoxime (saoH2), tetramethylammonium hydroxide (Me4NOH) with the appropriate lanthanide nitrate salt (Ln(NO3)3·6H2O). The metallic skeletons of the complexes describe [Ln4] tetrahedra encapsulated inside a [Ln4] square with the inner core stabilised through µ3-OH(-) ions and the periphery by µ4-sao(2-) ligands. The magnetic properties of compounds were investigated by dc and ac magnetometry. Temperature dependent ac magnetic susceptibility data reveal that the dysprosium analogue () displays an out-of-phase signal in the absence of an applied magnetic field indicative of slow relaxation of the magnetization typical of a Single-Molecule Magnet (SMM). Micro-SQUID measurements reveal temperature and sweep rate dependent hysteresis below 1.0 K.

13.
Chemistry ; 19(10): 3348-57, 2013 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-23345199

RESUMO

Reactions of the main-group cation Tl(I) with anions of 2,5-derivatives of TCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane) have led to the isolation of a family of unprecedented semiconducting main-group-metal-organic frameworks, namely, [Tl(TCNQX(2))], (X = H, Cl, Br, I). A comparison of single-crystal and powder X-ray diffraction data revealed the existence of a third polymorph of the previously reported material Tl(TCNQ)] and two distinct polymorphs of [Tl(TCNQCl(2))], whereas only one phase was identified for [Tl(TCNQBr(2))] and [Tl(TCNQI(2))]. These new results are described in the context of the structures of other known binary metal-TCNQ frameworks that display a variety of coordination environments for the central cation, namely, four-, six-, and eight-coordinate, and different arrangements of the adjacent TCNQ radicals-parallel versus perpendicular-in the stacked columns. The halogen substituents affect the structures and the properties of these compounds, owing to both steric and electronic effects as evidenced by the semiconducting properties of crystals of [Tl(TCNQCl(2))] phase I, [Tl(TCNQBr(2))], and [Tl(TCNQI(2))], which correlate well with the distances of adjacent TCNQ radicals in the columns. 1D infinite Hückel model simulations of the band structures of [Tl(TCNQCl(2))] phase I, [Tl(TCNQBr(2))], and [Tl(TCNQI(2))] were conducted with and without consideration of the Tl(I) cations, the results of which indicate that the charge mobility does not strictly occur in one dimension. The modulations of the band structures with various assumptions of the energy difference (Δ) between the Tl(I) 6s orbital and the TCNQ LUMO orbital were calculated and are discussed in light of the observed properties.

14.
Dalton Trans ; 42(1): 54-7, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23124493

RESUMO

The π-π stacking interactions between tptz units from adjacent Sm(tptz)(HCOO)(3) coordination nanotubes leads to additional 1D channels (tptz = 2,4,6-tris(2-pyridyl)-s-triazine). The present compound is a rare case of a tubular porous material with both hydrophobic and hydrophilic channels. Permanent porosity was confirmed by N(2) adsorption isotherms.

18.
Dalton Trans ; 39(18): 4341-52, 2010 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-20422092

RESUMO

Reactions between trivalent rare earth ions (M(III) = La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er and Yb) and the radical anion of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (TCNQF(4)) produce a family of mononuclear complexes {M[(TCNQF(4))](2)[H(2)O](x)}.(TCNQF(4))(3H(2)O), x = 6, 7. The cationic complex {M(III)([TCNQF(4)](-) )(2)[H(2)O](x)}(+) cocrystallizes with one [TCNQF(4)](-) radical anion and three water molecules. One of the coordinated [TCNQF(4)](-) radicals is involved in pi-pi stacking interactions with the uncoordinated [TCNQF(4)](-) radicals which leads to the antiferromagnetic coupling for these ((TCNQF(4))(2))(2-)pi-dimers. The second coordinated [TCNQF(4)](-) remains as a radical ligand and is not involved in pi-pi interactions. Magnetic studies indicate that the Sm compound magnetically orders at 4.4 K and that a fraction of the Gd and Dy samples undergo magnetic ordering at 3.7 K and 4.3 K respectively due to partial dehydration (loss of interstitial water molecules). Diamagnetic metal ions were used to generate magnetically dilute Gd, and Dy compounds that do not exhibit any signs of magnetic ordering.

20.
Chemistry ; 15(42): 11390-400, 2009 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-19760709

RESUMO

A series of isostructural compounds with formula [M(TCNQF(4))(2)(H(2)O)(6)]TCNQF(4)3 H(2)O (M=Tb (1), Y (2), Y:Tb (74:26) (3), and Y:Tb (97:3) (4); TCNQF(4)= tetrafluorotetracyanoquinodimethane) were prepared and their magnetic properties investigated. Compounds 1, 3, and 4 show the beginning of a frequency-dependent out-of-phase ac signal, and decreasing intensity of the signal with decreased concentration of Tb(III) ions in the diluted samples is observed. No out-of-phase signal was observed for 2, an indication that the behavior of 1, 3, and 4 is indicative of slow paramagnetic relaxation of Tb(III) ions in the samples. A more detailed micro-SQUID study at low temperature revealed an interplay between single-molecule magnetic (SMM) behavior and a phonon bottleneck (PB) effect, and that these properties depend on the concentration of diamagnetic yttrium ions. A combination of SMM and PB phenomena was found for 1, whereby the PB effect increases with increasing dilution until eventually a pure PB effect is observed for 2. The PB behavior is interpreted as being due to the presence of a "sea of organic S=1/2 radicals" from the TCNQF(4) radicals in these compounds. The present data underscore the fact that the presence of an out-of-phase ac signal may not, in fact, be caused by SMM behavior, particularly when magnetic metal ions are combined with organic radical ligands such as those found in the organocyanide family.

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