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1.
Int J Behav Med ; 30(4): 486-496, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35794410

RESUMO

BACKGROUND: Socio-environmental factors may affect uptake and utility of behavioral interventions targeting weight loss and cardiometabolic health. To evaluate the relation of neighborhood walkability to physical activity (PA) and glucose control in a sample of adults with overweight/obesity participating in a weight loss study. METHODS: Secondary analysis of a 12-month behavioral weight loss intervention (2011-2015) using one-group pretest-posttest design. Neighborhood walkability was assessed via residential Walk Score (0-100) at study entry. Fasting plasma glucose (FPG) via phlebotomy and PA via waist-worn ActiGraph GT3X were assessed at baseline and end of study. Study variables included neighborhood walkability (car-dependent: Walk Score < 50 vs. walkable: Walk Score ≥ 50), prediabetes (FPG 100-125 mg/dL), and recommended PA (moderate to vigorous PA [MVPA] > 22 min/day). Generalized linear model with logit link results were reported as adjusted odds ratios (AOR) with 95% confidence intervals (CI). RESULTS: The sample (N = 114) was mostly female (88.6%), white (83.3%), college educated (73.7%), and on average 51.4 ± 1.0 years of age. At baseline, persons residing in car-dependent neighborhoods tended to have higher income than those in walkable neighborhoods. Neighborhood walkability interacted with household income at study entry to predict participants' ability to meet the MVPA goal at 12 months (AOR = 13.52, 95% CI: 1.86-119.20). Those from walkable neighborhoods had 67% lower odds of having prediabetes compared to those from car-dependent neighborhoods (AOR = 0.33, 95% CI: 0.10-0.87) at 12 months. CONCLUSION: Our findings corroborate previous research characterizing the relationship between neighborhood walkability, PA, and prediabetes status. Key drivers of this impact warrant further investigation in a study with a larger, more diverse sample.


Assuntos
Estado Pré-Diabético , Adulto , Humanos , Feminino , Masculino , Estado Pré-Diabético/terapia , Planejamento Ambiental , Exercício Físico , Caminhada , Redução de Peso , Características de Residência
2.
Ann Surg ; 275(4): 718-726, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32889873

RESUMO

OBJECTIVE: To examine associations of objectively-measured physical activity (PA) with changes in weight after roux-en-Y gastric bypass (RYGB) over 7 years. BACKGROUND: The contribution of free-living PA to surgery-induced weight loss and subsequent weight regain is not well understood. METHODS: Participants of a multi-center prospective cohort study of bariatric surgery were followed annually ≥7 years. Of 807 participants who underwent RYGB and were given an activity monitor, 649 (80%) had sufficient data for this report (78% female; median age 47 years; median body mass index 46 kg/m2). Mean daily steps, hours/day in SB and minutes/week in moderate-to-vigorous physical activity (MVPA) were determined at each assessment. Mixed models tested associations between PA measures and weight outcomes, controlling for sociodemographics, health status, and eating behaviors. RESULTS: Across follow-up, mean pre to postsurgery changes in PA were small, and mean postsurgery PA level was below PA recommendations for health (eg, 101 MVPA min/week 7 years postsurgery versus the ≥150 MVPA min/week recommendation). There was a dose-response association between more steps, less SB and more MVPA with greater weight loss. Steps and SB, but not MVPA, were also associated with weight regain. For example, participants in the highest versus lowest steps quartile lost 2.9% (95% confidence interval, 1.8-4.1) more of their presurgery weight and regained 5.4% (95% confidence interval, 2.4-8.3) less of their maximum weight lost across follow-up. CONCLUSIONS: Despite only small increases in objectively-measured PA level after RYGB, PA level was independently associated with weight outcomes of bariatric surgery throughout 7 years of follow-up. REPRINTS: Reprints will not be available from the authors.


Assuntos
Derivação Gástrica , Obesidade Mórbida , Índice de Massa Corporal , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Estudos Prospectivos , Aumento de Peso , Redução de Peso/fisiologia
3.
Molecules ; 27(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36234951

RESUMO

The corrosion of industrial material is a costly problem associated with global economic losses reaching trillions of US dollars in the repair of failures. Injecting corrosion inhibitors is the most practically promising method for decelerating corrosion reactions and protecting surfaces. Recent investigations have focused on surfactants as corrosion inhibitors due to their amphiphilic nature, low cost, and simple chemical preparation procedures. This study aims to investigate the performance of an environment-friendly Quaternium-22 (Q-22) surfactant which is widely used in cosmetics for C-steel corrosion inhibition in a 5 M HCl medium. Weight loss experiments were performed at different concentrations and immersion times, presenting a maximum efficiency at 2.22 mmol·L-1. The influence of Q-22 on the corrosion behavior of C-steel was elucidated using non-destructive electrochemical measurements. The overall results revealed that adding varied concentrations of Q-22 significantly decreases the corrosion rate of C-steel. The results revealed the physisorption nature of Q-22 onto the C-steel surface, with adsorption following the Freundlich isotherm (∆Hads= -16.40 kJ·mol-1). The relative inhibition performance of Q-22 was also evaluated by SEM and AFM analyses. Lastly, quantum chemical calculations based on density functional theory (DFT) demonstrated that Q-22 has promising molecular features concerning the anticorrosive mechanism.


Assuntos
Carbono , Aço , Carbono/química , Corrosão , Compostos de Amônio Quaternário , Aço/química , Tensoativos
4.
Polymers (Basel) ; 14(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35745909

RESUMO

The calcium carbonate (CaCO3) scale is one of the most common oilfield scales and oil and gas production bane. CaCO3 scale can lead to a sudden halt in production or, worst-case scenario, accidents; therefore, CaCO3 scale formation prevention is essential for the oil and gas industry. Scale inhibitors are chemicals that can mitigate this problem. We used two popular theoretical techniques in this study: Density Functional Theory (DFT) and Ab Initio Molecular Dynamics (AIMD). The objective was to investigate the inhibitory abilities of mixed oligomers, specifically acrylamide functionalized silica (AM-Silica). DFT studies indicate that Ca2+ does not bind readily to acryl acid and acrylamide; however, it has a good binding affinity with PAM and Silica functionalized PAM. The highest binding affinity occurs in the silica region and not the -CONH functional groups. AIMD calculations corroborate the DFT studies, as observed from the MD trajectory that Ca2+ binds to PAM-Silica by forming bonds with silicon; however, Ca2+ initially forms a bond with silicon in the presence of water molecules. This bonding does not last long, and it subsequently bonds with the oxygen atoms present in the water molecule. PAM-Silica is a suitable calcium scale inhibitor because of its high binding affinity with Ca2+. Theoretical studies (DFT and AIMD) have provided atomic insights on how AM-Silica could be used as an efficient scale inhibitor.

5.
Saudi J Kidney Dis Transpl ; 33(5): 617-626, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37955454

RESUMO

Lupus nephritis (LN) is a major risk factor for morbidity and mortality in systemic lupus erythematosus (SLE). Urinalysis has an invaluable role in the diagnosis of various renal and urological diseases. Examinations of the urinary sediment using phase contrast microscopy (PCM) may add more information to help earlier diagnoses of LN. This cross-sectional study aimed to assess the possible role of the components of urinary sediment examined using PCM in discriminating the proliferative classes of LN (III and IV ± V) from the non-proliferative classes (I, II, and V), and to detect the correlation between the components of urinary sediment and indices of both activity and chronicity found by the renal biopsy. The study was conducted on 40 SLE patients for whom a renal biopsy was indicated. Clinical, demographic, and laboratory data and the results of the histopathological renal biopsy were collected. The morning before the renal biopsy; urine samples were collected from every patient and examined by PCM. Receiver operating characteristic curves were used to detect the area under the curve to predict proliferative LN. The correlations of counts of leukocytes, erythrocytes, all dysmorphic erythrocytes, acanthocytes, and stomatocytes with the indices of activity and chronicity were significant (activity: P = 0.027, P = 0.015, P = 0.033, P = 0.040, and P <0.001*; chronicity: P = 0.035, P = 0.009, P = 0.027, P = 0.010, and P <0.001, respectively). For patients with SLE, urinary sediment examinations can suggest a renal biopsy for the histopathology of LN.


Assuntos
Rim , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Biomarcadores/urina , Estudos Transversais , Rim/patologia , Lúpus Eritematoso Sistêmico/patologia , Nefrite Lúpica/patologia , Análise do Sedimento Urinário , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
6.
ACS Omega ; 6(47): 32120-32132, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34870033

RESUMO

Scale prevention is a long-term challenge. It is essential for ensuring the optimum utilization of oil and gas wells and minimizing economic losses due to disruptions in the hydrocarbon flow. Among the commonly precipitated scales is calcite, especially in oilfield production facilities. Previous studies on scale inhibitors have focused on investigating the performance of several phosphonates and carboxylates. However, the increased environmental awareness has pushed toward investigating environmental-friendly inhibitors. Research studies demonstrated the potential of using amino acids as standalone inhibitors or as inhibitor-modifying reagents. In this study, 10 amino acids for calcite inhibitors have been investigated using molecular simulations. Eco-toxicity, quantum chemical calculations, binding energy, geometrical, and charge analyses were all evaluated to gain a holistic view of the behavior and interaction of these inhibitors with the calcite {1 0 4} surface. According to the DFT simulation, alanine, aspartic acid, phenylalanine, and tyrosine amino acids have the best inhibitor features. The results revealed that the binding energies were -2.16, -1.75, -2.24, and -2.66 eV for alanine, aspartic acid, phenylalanine, and tyrosine, respectively. Therefore, this study predicted an inhibition efficiency of the order tyrosine > phenylalanine > alanine > aspartic acid. The predicted inhibition efficiency order reveals agreement with the reported experimental results. Finally, the geometrical and charge analyses illustrated that the adsorption onto calcite is physisorption in the acquired adsorption energy range.

7.
Sci Rep ; 11(1): 4796, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637829

RESUMO

Pyrite scale formation is a critical problem in the hydrocarbon production industry; it affects the flow of hydrocarbon within the reservoir and the surface facilities. Treatments with inorganic acids, such as HCl, results in generation toxic hydrogen sulfide, high corrosion rates, and low dissolving power. In this work, the dissolution of pyrite scale is enhanced by the introduction of electrical current to aid the chemical dissolution. The electrolytes used in this study are chemical formulations mainly composed of diethylenetriamine-pentaacetic acid-potassium (DTPAK5) with potassium carbonate; diethylenetriamine pentaacetic acid sodium-based (DTPANa5), and L-glutamic acid-N, N-diacetic acid (GLDA). DTPA and GLDA have shown some ability to dissolve iron sulfide without generating hydrogen sulfide. The effect of these chemical formulations, disc rotational rate and current density on the electro-assisted dissolution of pyrite are investigated using Galvanostatic experiments at room temperature. The total iron dissolved of pyrite using the electrochemical process is more than 400 times higher than the chemical dissolution using the same chelating agent-based formulation and under the same conditions. The dissolution rate increased by 12-folds with the increase of current density from 5 to 50 mA/cm2. Acid and neutral formulations had better dissolution capacities than basic ones. In addition, doubling the rotational rate did not yield a significant increase in electro-assisted pyrite scale dissolution. XPS analysis confirmed the electrochemical dissolution is mainly due to oxidation of Fe2+ on pyrite surface lattice to Fe3+. The results obtained in this study suggest that electro-assisted dissolution is a promising technique for scale removal.

8.
ACS Omega ; 6(16): 10607-10617, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-34056214

RESUMO

Sulfate-reducing bacteria (SRB), such as Desulfobacter postgatei are found in oil wells. However, they lead to the release of hydrogen sulfide. This in turn leads to the iron sulfide scale formation (pyrite). ATP sulfurylase is an enzyme present in SRB, which catalyzes the formation of adenylyl sulfate (APS) and inorganic pyrophosphatase (PPi) from ATP and sulfate. This reaction is the first among many in hydrogen sulfide production by D. postgatei . Consensus scoring using molecular docking and machine learning was used to identify three potential inhibitors of ATP sulfurylase from a database of about 40 million compounds. These selected hits ((S,E)-1-(4-methoxyphenyl)-3-(9-((m-tolylimino)methyl)-9,10-dihydroanthracen-9-yl)pyrrolidine-2,5-dione; methyl 2-[[(1S)-5-cyano-2-imino-1-(4-phenylthiazol-2-yl)-3-azaspiro[5.5]undec-4-en-4-yl]sulfanyl]acetate; and (4S)-4-(3-chloro-4-hydroxy-phenyl)-1-(6-hydroxypyridazin-3-yl)-3-methyl-4,5-dihydropyrazolo[3,4-b]pyridin-6-ol), known as A, B, and C, respectively) all had good binding affinities with ATP sulfurylase and were further analyzed for their toxicological properties. Compound A had the highest docking score. However, based on the physicochemical and toxicological properties, only compound C was predicted to be both safe and effective as a potential inhibitor of ATP sulfurylase, hence the preferred choice. The molecular interactions of compound C revealed favorable interactions with the following residues: LEU213, ASP308, ARG307, TRP347, LEU224, GLN212, MET211, and HIS309.

9.
Front Pharmacol ; 12: 731483, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002691

RESUMO

Huntington's disease (HD) is an autosomal dominant inherited neurodegenerative disease characterized by progressive motor, psychiatric, and cognitive abnormalities. The antidiabetic drug liraglutide possesses a neuroprotective potential against several neurodegenerative disorders; however, its role in Huntington's disease (HD) and the possible mechanisms/trajectories remain elusive, which is the aim of this work. Liraglutide (200 µg/kg, s.c) was administered to rats intoxicated with 3-nitropropionic acid (3-NP) for 4 weeks post HD model induction. Liraglutide abated the 3-NP-induced neurobehavioral deficits (open field and elevated plus maze tests) and histopathological changes. Liraglutide downregulated the striatal mRNA expression of HSP 27, PBR, and GFAP, while it upregulated that of DARPP32. On the molecular level, liraglutide enhanced striatal miR-130a gene expression and TrKB protein expression and its ligand BDNF, while it reduced the striatal protein content and mRNA expression of the death receptors sortilin and p75NTR, respectively. It enhanced the neuroprotective molecules cAMP, p-PI3K, p-Akt, and p-CREB, besides modulating the p-GSK-3ß/p-ß-catenin axis. Liraglutide enhanced the antioxidant transcription factor Nrf2, abrogated TBARS, upregulated both Bcl2 and Bcl-XL, and downregulated Bax along with decreasing caspase-3 activity. Therefore, liraglutide exerts a neurotherapeutic effect on 3-NP-treated rats that is, besides the upturn of behavioral and structural findings, it at least partially, increased miR-130a and modulated PI3K/Akt/CREB/BDNF/TrKB, sortilin, and p75NTR, and Akt/GSK-3ß/p-ß-catenin trajectories besides its capacity to decrease apoptosis and oxidative stress, as well as its neurotrophic activity.

10.
J Taibah Univ Med Sci ; 16(4): 482-490, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34408604

RESUMO

OBJECTIVES: This study investigates the link between low socioeconomic status (SES) and advanced thyroid cancer at the time of detection. It also assesses the socioeconomic variables that may potentially affect the stage of thyroid cancer at presentation. METHODS: This retrospective cohort study was conducted on patients with thyroid cancer between January 2016 and April 2020. The data were collected using the patients' medical records from the hospital information system (BESTcare) and through interview-based surveys. To assess the factors predicting the stage of advanced thyroid cancer, socioeconomic status (SES) predictors like area of residency, educational level, income, and marital status were collected. RESULTS: A total of 220 patients with thyroid cancer were included in this study. Male patients (p = 0.025), older than 55 years (p < 0.001), living in rural areas (p = 0.002), with low educational level (p = 0.021) were found to be significantly associated with advanced-stage thyroid cancer at presentation. Multivariate analysis showed that gender (men) and age (above 55 years) were significant predictors of advanced stage thyroid cancer. However, no association between income and the stage of thyroid cancer has been found in this study. CONCLUSION: This study has shown that even in a country like KSA with a strong government-funded healthcare system, health disparity among people battling thyroid cancer exists. Our study has found that SES factors have a significant impact on the stage of thyroid cancer at the time of presentation, whereas the economic status of the patients had no impact on the stage of thyroid cancer. Furthermore, patients in lower SES groups were diagnosed with more advanced stages at presentation.

11.
ACS Omega ; 5(46): 29963-29970, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33251432

RESUMO

Scale mineral deposition is a critical problem that hinders the daily production of oil and gas fields. Chemical removal of these scales, based on the scale type, is common. In this paper, borax and diethylene tremaine penta acetic (DTPA) acid-based formulations are used for the removal of sulfides, carbonates, and sulfate scales. In particular, the dissolution rates of sulfide (pyrite, pyrrhotite, and galena), sulfate (celestite and barite), and carbonate (calcite) scales were investigated in a rotating disc apparatus at typical well conditions. Scanning electron microscopy-energy-dispersive X-ray and X-ray diffraction analyses were performed for characterizing scale composition and type. The effect of temperature, scale type, and formulation on the dissolution rate is studied. Even though borax formulation has been developed for the sulfide scale removal, it showed a high dissolution rate for the carbonate scale (7.23 × 10-7 mol·L-1·s-1·cm-2). For the sulfide scale, the highest dissolution in borax formulation was obtained with galena (lead sulfide, PbS), followed by pyrrhotite, and the lowest dissolution was reported for pyrite (1.55 × 10-8 mol·L-1·s-1·cm-2). Borax formulation was found to be inefficient in the removal of sulfate scales with a dissolution rate lower than carbonate and sulfide scales by 3 and 2 orders of magnitude, respectively. Similarly, DTPA-based formulation has yielded the highest dissolution for the carbonate scale (7.98 × 10-6 mol·L-1·s-1·cm-2). However, for sulfate, DTPA-based formulation showed better performance than borax. The increase in temperature leads to an increase in the dissolution rate for almost all types of scales; however, DTPA-based formulation showed improved performance with temperature. Both formulations are efficient in removing sulfate- and sulfide-rich scales. The experimental results of DTPA have been validated by density functional theory calculations of binding energies between DTPA and metal ions present in the mixed scale.

12.
ACS Omega ; 5(24): 14308-14315, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32596568

RESUMO

In the oil and gas industry, pyrite forms one of the most hardened scales in reservoirs, which hinders the flow of fluids. Consequently, this leads to blockage of the downhole tubular, formation damage, and complete shutdown of production and operational processes. Herein, a new green formulation based on borax (K2B4O7) is proposed for pyrite scale removal. The temperature effect, disk rotational speed, and borax concentration have been investigated using a rotating disk apparatus. Also, XPS and SEM-EDX analyses were conducted on the pyrite disk surface before and after the treatment with the green formulation. The new formulation showed the potential ability to dissolve pyrite without generating the toxic hydrogen sulfide (H2S). The dissolution rate of the scale in the new formulation is increased by 16% compared to that in a previous green formulation composed of 20 wt %DTPA+9 wt % K2CO3. Molecular modeling technique using DFT was used to study the solvation energies of Fe2+ and Fe3+. The latter had a higher solvation energy than the former, which confirmed that upon using the borax-based formulation to oxidize Fe2+ to Fe3+. It will aid the dissolution of pyrite scales. The new formulation achieved a corrosion rate that is 25 times lower than that of 15 wt % HCl, which is commercially used in treating scales. Finally, the proposed new formulation does not require the use of corrosion inhibitors; hence, it is expected to result in a more economical scale treatment method.

13.
Ind Eng Chem Res ; 57(31): 10095-10104, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30270976

RESUMO

A common problem that faces the oil and gas industry is the formation of iron sulfide scale in various stages of production. Recently an effective chemical formulation was proposed to remove all types of iron sulfide scales (including pyrite), consisting of a chelating agent diethylenetriaminepentaacetic acid (DTPA) at high pH using potassium carbonate (K2CO3). The aim of this molecular modeling study is to develop insight into the thermodynamics and kinetics of the chemical reactions during scale removal. A cluster approach was chosen to mimic the overall system. Standard density functional theory (B3LYP/6-31G*) was used for all calculations. Low spin K4Fe(II)4(S2H)12 and K3Fe(II)(S2H)5 clusters were derived from the crystal structure of pyrite and used as mimics for surface scale FeS2. In addition, K5DTPA was used as a starting material too. High spin K3Fe(II)DTPA, and K2S2 were considered as products. A series of K m Fe(II)(S2H) n complexes (m = n-2, n = 5-0) with various carboxylate and glycinate ligands was used to establish the most plausible reaction pathway. Some ligand exchange reactions were investigated on even simpler Fe(II) complexes in various spin states. It was found that the dissolution of iron sulfide scale with DTPA under basic conditions is thermodynamically favored and not limited by ligand exchange kinetics as the activation barriers for these reactions are very low. Singlet-quintet spin crossover and aqueous solvation of the products almost equally contribute to the overall reaction energy. Furthermore, seven-coordination to Fe(II) was observed in both high spin K3Fe(II)DTPA and K2Fe(II)(EDTA)(H2O) albeit in a slightly different manner.

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