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1.
Nutr Metab Cardiovasc Dis ; 34(9): 2021-2033, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38866619

RESUMEN

AIM: The guidelines recommend statins to prevent cardiovascular events in patients with type 2 diabetes (T2D) however, the importance of baseline LDL-Cholesterol (LDL-C) levels remains controversial. This study aimed to determine the association of statin use in T2D patients with major adverse cardiovascular events (MACE) and all-cause mortality and whether this association differs by baseline LDL-C levels. DATA SYNTHESIS: Medline, Embase, and Web of Science were systematically searched from inception until January 2022. Observational studies in patients with T2D comparing statin users vs non-users, with reports of the baseline LDL-C levels, were included. Random-effects meta-analysis and meta-regression were performed to estimate the overall effect on the risk of all-cause mortality and MACE (a composite of myocardial infarction, heart failure, stroke, and revascularization events) and the modification in the association by baseline LDL-C levels. We categorized studies according to their baseline LDL-C levels into 1) <100 mg/dl (2.59 mmol/l), 2) 100-130 mg/dl (2.59-3.37 mmol/l) and 3) >130 mg/dl (3.37 mmol/l) categories. A total of 9 cohort studies (n = 403,411 individuals) fulfilled our criteria. The follow-up duration ranged from 1.7 to 8 years. The overall combined estimate showed that statin therapy was associated with a significantly lower risk of MACE (Hazard Ratio (HR): 0.70 [95% CI 0.59 to 0.83], Absolute risk reduction percentage (ARR%): 3.19% [95%CI 0.88 to 5.50%) and all-cause mortality (HR: 0.60 [95% CI 0.46 to 0.79], ARR%: 5.23% [95% CI 2.18 to 8.28%), but varied, albeit not statistically significant, by baseline LDL-C levels. Studies with baseline LDL-C levels higher than 130 mg/dl had the greatest reduction of MACE (HR: 0.58 [95% CI 0.37 to 0.90]) and all-cause mortality risk (HR: 0.51 [95% CI [ 0.29 to 0.90]). The HRs of MACE in studies with LDL-C levels of 100-130 mg/dl and <100 mg/dl categories were respectively (0.70 [95% CI 0.59 to 0.83]) and (0.83 [95% CI [0.68 to 1.00]); and that of all-cause mortality were respectively (0.62 [95% CI 0.38 to 1.01]) and (0.67 [95% CI [0.44 to 1.02]). Statin use changes the HRs of MACE (0.99 [95%CI, 0.98 to 0.99]; P = 0.04) and all-cause mortality (0.99 [95% CI 0.98 to 1.01]; P = 0.8) per each mg/dl increase in baseline LDL-C level in meta-regression analyses. CONCLUSION: Statin therapy in patients with T2D was associated with reduced risk of MACE and all-cause mortality. Significant differences across studies with different baseline LDL-C levels were not observed.


Asunto(s)
Biomarcadores , Enfermedades Cardiovasculares , LDL-Colesterol , Diabetes Mellitus Tipo 2 , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Estudios Observacionales como Asunto , Humanos , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/mortalidad , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/complicaciones , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , LDL-Colesterol/sangre , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/epidemiología , Medición de Riesgo , Biomarcadores/sangre , Femenino , Masculino , Resultado del Tratamiento , Persona de Mediana Edad , Anciano , Dislipidemias/sangre , Dislipidemias/tratamiento farmacológico , Dislipidemias/mortalidad , Dislipidemias/diagnóstico , Factores Protectores , Factores de Tiempo
2.
Heliyon ; 9(3): e13766, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36851970

RESUMEN

Background: The bidirectional brain-machine interfaces algorithms are machines that decode neural response in order to control the external device and encode position of artificial limb to proper electrical stimulation, so that the interface between brain and machine closes. Most BMI researchers typically consider four basic elements: recording technology to extract brain activity, decoding algorithm to translate brain activity to the predicted movement of the external device, external device (prosthetic limb such as a robotic arm), and encoding interface to convert the motion of the external machine to set of the electrical stimulation of the brain. New method: In this paper, we develop a novel approach for bidirectional brain-machine interface (BMI). First, we propose a neural network model for sensory cortex (S1) connected to the neural network model of motor cortex (M1) considering the topographic mapping between S1 and M1. We use 4-box model in S1 and 4-box in M1 so that each box contains 500 neurons. Individual boxes include inhibitory and excitatory neurons and synapses. Next, we develop a new BMI algorithm based on neural activity. The main concept of this BMI algorithm is to close the loop between brain and mechaical external device. Results: The sensory interface as encoding algorithm convert the location of the external device (artificial limb) into the electrical stimulation which excite the S1 model. The motor interface as decoding algorithm convert neural recordings from the M1 model into a force which causes the movement of the external device. We present the simulation results for the on line BMI which means that there is a real time information exchange between 9 boxes and 4 boxes of S1-M1 network model and the external device. Also, off line information exchange between brain of five anesthetized rats and externnal device was performed. The proposed BMI algorithm has succeeded in controlling the movement of the mechanical arm towards the target area on simulation and experimental data, so that the BMI algorithm shows acceptable WTPE and the average number of iterations of the algorithm in reaching artificial limb to the target region.Comparison with existing methods and Conclusions: In order to confirm the simulation results the 9-box model of S1-M1 network was developed and the valid "spike train" algorithm, which has good results on real data, is used to compare the performance accuracy of the proposed BMI algorithm versus "spike train" algorithm on simulation and off line experimental data of anesthetized rats. Quantitative and qualitative results confirm the proper performance of the proposed algorithm compared to algorithm "spike train" on simulations and experimental data.

4.
Sci Rep ; 12(1): 19436, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36376426

RESUMEN

Artificial intelligence computing adapted from biology is a suitable platform for the development of intelligent machines by imitating the functional mechanisms of the nervous system in creating high-level activities such as learning, decision making and cognition in today's systems. Here, the concentration is on improvement the cognitive potential of artificial intelligence network with a bio-inspired structure. In this regard, four spiking pattern recognition platforms for recognizing digits and letters of EMNIST, patterns of YALE, and ORL datasets are proposed. All networks are developed based on a similar structure in the input image coding, model of neurons (pyramidal neurons and interneurons) and synapses (excitatory AMPA and inhibitory GABA currents), and learning procedure. Networks 1-4 are trained on Digits, Letters, faces of YALE and ORL, respectively, with the proposed un-supervised, spatial-temporal, and sparse spike-based learning mechanism based on the biological observation of the brain learning. When the networks have reached the highest recognition accuracy in the relevant patterns, the main goal of the article, which is to achieve high-performance pattern recognition system with higher cognitive ability, is followed. The pattern recognition network that is able to detect the combination of multiple patterns which called intertwined patterns has not been discussed yet. Therefore, by integrating four trained spiking pattern recognition platforms in one system configuration, we are able to recognize intertwined patterns. These results are presented for the first time and could be the pioneer of a new generation of pattern recognition networks with a significant ability in smart machines.


Asunto(s)
Inteligencia Artificial , Redes Neurales de la Computación , Potenciales de Acción/fisiología , Algoritmos , Reconocimiento de Normas Patrones Automatizadas/métodos
5.
Genes (Basel) ; 13(6)2022 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-35741728

RESUMEN

BACKGROUND: Prior studies have reported inconsistent results or less well-explored associations between sex hormones and non-alcoholic fatty liver disease (NAFLD). Here, we aimed to investigate the associations of NAFLD with sex steroids and sex hormone-binding globulin (SHBG) in the population-based study and conduct a comprehensive systematic review and meta-analysis of all published observational studies. METHODS: Analyses included 755 men and 1109 women with available data on sex steroids, SHBG, and ultrasound-based NAFLD from the Rotterdam Study. Multivariable regression models were used to examine the associations. Additionally, we searched five databases from inception to 1 April 2022 and performed a systematic review and meta-analysis. Random-effects (DerSimonian-Laird) method was used for meta-analysis, odds ratios (ORs) were calculated for the effect estimate, subgroup and leave-one-out sensitivity analyses were conducted, and meta-regression was performed to explore the pooled statistics with high heterogeneity. RESULTS: In the Rotterdam Study, lower levels of SHBG were associated with NAFLD in both sexes, while lower testosterone was associated with NAFLD only among women. Similarly, the meta-analysis of 16 studies indicated no sex-specific association between SHBG and NAFLD (men: OR = 0.37, 95%CI 0.21-0.53; women: OR = 0.40, 95%CI 0.21-0.60), yet there was a sex-specific association between testosterone and NAFLD (men: OR = 0.59, 95%CI 0.42-0.76; women: OR = 1.06, 95%CI 0.68-1.44). Moreover, men with NAFLD had lower estradiol levels than those without NAFLD. CONCLUSIONS: Lower SHBG levels were associated with NAFLD in both sexes, but testosterone levels were associated in a sex-specific manner. In addition, our results showed estradiol with the potential as a protective factor for NAFLD in healthy men.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Globulina de Unión a Hormona Sexual , Estradiol , Femenino , Hormonas Esteroides Gonadales , Humanos , Masculino , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Testosterona
6.
Int J Prev Med ; 13: 151, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36911005

RESUMEN

This is a comprehensive review based on the published papers in the field of COVID-19 vaccines and vaccination. Many efforts have been made to develop vaccines to combat this pandemic. Since December 2020, more than 200 vaccines have been tested in various research stages and in clinical trials on humans, of which eight vaccines reached phase four clinical trials in humans and approved by FDA and EUA. After the Pfizer-BioNTech vaccine that had the highest efficacy (95%), the efficacy of the other vaccines are as follows: Moderna 94.5%, Sputnik V 91%, Novavax 89.7%, Sinopharm 79.3%, Oxford/AstraZenaca 70.4%, Johnson and Johnson 66.9%, and Sinovac 50.7%. At present, protein-based vaccines, with 35% of all available COVID-19 vaccines, are the most common technique in the vaccine production, and then there are vaccines of non-replicating viral vector (13.3%), mRNA1 (12.1%), DNA (10.2%), replicating viral vector (9.8%), and inactivated vaccines (8.2%). The most frequently recognized adverse effects within 7 days of each vaccine dose involved fever, fatigue, headache, chill, and myalgia. The mRNA-based vaccines were associated with a higher occurrence of local side effects (78.3 vs. 70.4%; Sig. = 0.064), whereas the viral vector-based vaccine was associated with a higher prevalence of systemic side effects (87.2 vs. 61%; Sig. < 0.001). Based on the evidence and articles in the field of vaccination, AstraZeneca-Oxford and Sinopharm vaccines reported the highest and lowest side effects, respectively. Because of being emerging, pathogenicity, and high infectivity of COVID-19, vaccination against the disease to prevent its incident rate and decrease the prevalence rate is recommended immediately. Being informed of various aspects of the existing vaccines such as efficacy, effectiveness, safety, etc.can accelerate to make effective and useful choices and consequently have a vaccinated community against the epidemic.

7.
J Clin Transl Res ; 7(1): 49-60, 2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-34104808

RESUMEN

BACKGROUND: Multiple sclerosis (MS), as the most common neurologic disorder of the central nervous system, with growing incidence and prevalence worldwide and in the Middle East. This article aimed to find out the potential relationship between MS and air pollution in Iran. METHODS: By assessing the published articles on MS and air pollution in Iran, the situation of MS as well as air/soil pollution in Iran was clarified. Then, studies on air pollution and its potential effect on Iranian MS patients were checked until 2020. RESULTS: The MS prevalence is distributed across Iran Provinces with highest rates in Isfahan, located in the center of Iran. The higher rates of MS in Isfahan and Tehran (the Metropolitan) might be due to industrial pollution of these cities, but this hypothesis is not true for non-industrial provinces. Based on the published atlas of MS in Iran, it seems that there is a high-risk "belt" from northwest to southeast. CONCLUSION: There are many risk factors of MS in Iran including age, gender, Vitamin D deficiency, smoking, and air pollution. The potential main risk factor of MS might be air pollution considering Isfahan and Tehran provinces. However, Chahar Mahal and Bakhtiary Province, with non-industrial nature, has the second highest MS rates which does not follow this hypothesis. RELEVANCE FOR PATIENTS: By finding the air pollution as the main potential risk factor of MS in big provinces including Isfahan and Tehran, its effect of this factor can also be considered during diagnosis and treatment.

8.
Eur J Clin Invest ; 51(5): e13479, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33350463

RESUMEN

BACKGROUND: Fatty liver disease (FLD), primarily nonalcoholic fatty liver disease (NAFLD), is the most common liver disorder that affects a quarter of the global population. NAFLD is a spectrum of disease ranging from simple steatosis to nonalcoholic steatohepatitis, which is associated with increased risk of developing liver cancer. Given that the pathogenic mechanisms of fatty liver remain largely elusive, it is important to further investigate potential underlying mechanisms including epigenetic modifications. Here, we performed a systematic review of human epigenetic studies on FLD presence. METHODS: Five bibliographic databases were screened until 28 August 2020. We included cross-sectional, case-control and cohort studies in humans that examined the association of epigenetic modifications including global, candidate or epigenome-wide methylation of DNA, noncoding RNAs and histone modifications with FLD. RESULTS: In total 36 articles, based on 33 unique studies, consisting of 12 112 participants met the inclusion criteria. Among these, two recent epigenome-wide association studies conducted among large population-based cohorts have reported the association between cg06690548 (SLC7A11) and FLD. Moreover, several studies have demonstrated the association between microRNAs (miRNAs) and FLD, in which miR-122, miR-34a and miR-192 were recognized as the most relevant miRNAs as biomarkers for FLD. We did not find any studies examining histone modifications in relation to FLD. CONCLUSIONS: Cumulative evidence suggests a link between epigenetic mechanisms, specifically DNA methylation and miRNAs, and FLD. Further efforts should investigate the molecular pathways by which these epigenetic markers may regulate FLD and also the potential role of histone modifications in FLD.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Código de Histonas , Enfermedad del Hígado Graso no Alcohólico/genética , ARN no Traducido , Epigenómica , Hígado Graso/genética , Humanos , MicroARNs
9.
Autism Res ; 13(9): 1582-1600, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32830427

RESUMEN

A combination of genetic and environmental factors contributes to the origins of autism spectrum disorder (ASD). While a number of studies have described specific environmental factors associating with emerging ASD, studies that compare and contrast multiple environmental factors in the same study are lacking. Thus, the goal of this study was to perform a prospective, data-driven environmental-wide association study of pre- and perinatal factors associated with the later development of autistic symptoms in childhood. The participants included 3891 6-year-old children from a birth cohort with pre- and perinatal data. Autistic symptoms were measured using the Social Responsiveness Scale in all children. Prior to any analyses, the sample was randomly split into a discovery set (2920) and a test set (921). Multiple linear regression analyses were performed for each of 920 variables, correcting for six of the most common covariates in epidemiological studies. We found 111 different pre- and perinatal factors associated with autistic traits during childhood. In secondary analyses where we controlled for parental psychopathology, 23 variables in the domains of family and interpersonal relationships were associated with the development of autistic symptoms during childhood. In conclusion, a data-driven approach was used to identify a number of pre- and perinatal risk factors associating with higher childhood autistic symptoms. These factors include measures of parental psychopathology and family and interpersonal relationships. These measures could potentially be used for the early identification of those at increased risk to develop ASD. LAY SUMMARY: A combination of genetic and environmental factors contributes to the development of autism spectrum disorder (ASD). Each environmental factor may affect the risk of ASD. In a study on 6-year-old children, a number of pre- and perinatal risk factors were identified that are associated with autistic symptoms in childhood. These factors include measures of parental psychopathology and family and interpersonal relationships. These variables could potentially serve as markers to identify those at increased risk to develop ASD or autistic symptoms. Autism Res 2020, 13: 1582-1600. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.


Asunto(s)
Trastorno del Espectro Autista/epidemiología , Trastorno del Espectro Autista/etiología , Ambiente , Trastorno Autístico/epidemiología , Trastorno Autístico/etiología , Niño , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo
10.
Oncol Rev ; 14(1): 463, 2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32477469

RESUMEN

Palliative care (PC) is one of the necessary cares given throughout a patient's experience with cancer. The aim of this study was to identify the perceived factors to providing PC for patients with cancer. Our study was a systematic review of qualitative literature. To this end, electronic databases, including CINAHL, PubMed, PsycINFO, Ovid, and Web of Science as well as Persian databases were searched and qualitative studies on the role of PC in patients with cancer published between Jan 2008 and Dec 2017 were selected. Generally, 12 studies were reviewed. A thematic synthesis approach was used to analyze the data. Exploring the selected articles, the findings on the perceived factors to providing PC for patients with cancer were categorized into three themes, including organizational factors, ethical factors, and psychological factors. This qualitative systematic review expands our knowledge about factors influencing the provision of PC for patients with cancer. It is necessary for health system managers and caregivers to pay attention to all aforesaid factors in order to improve PC for cancer patients.

11.
Talanta ; 210: 120641, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31987217

RESUMEN

The early diagnosis of cancer increases the chance of its treatment. In this study, an enzyme-free sandwich type of immunosensors is presented for prostate specific antigen (PSA), as prostate cancer biomarker. In this regard, the quantum dots (QDs) and magnetic metal-organic frameworks (MOFs) were used for labeling the secondary anybody and modifying the electrode surface, respectively. Herein, a bare glassy carbon electrodes is modified with iron magnetic nanoparticles with a core shell MOFs (magnetic framework Fe3O4@ TMU-10) and the primary antibodies (Ab1) are immobilized on the modified electrode. Moreover, the second antibody is successfully conjugated to a nickel-cadmium quantum dots as an electroactive non-enzymatic probe. The prepared immunosensor shows a linear range between 1 pg mL-1- 100 ng mL-1 and the detection limit of 0.45 pg mL-1 with acceptable selectivity, reproducibility and stability. The proposed sensor is also applied for determination of PSA in human serum samples and the results is confirmed by a reference method, which indicates its ability for clinical monitoring of the tumor marker.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Inmunoensayo , Estructuras Metalorgánicas/química , Antígeno Prostático Específico/análisis , Anticuerpos/química , Técnicas Biosensibles/instrumentación , Carbono/química , Técnicas Electroquímicas/instrumentación , Electrodos , Vidrio/química , Humanos , Inmunoensayo/instrumentación , Fenómenos Magnéticos , Tamaño de la Partícula , Puntos Cuánticos/química , Propiedades de Superficie
12.
IEEE Trans Neural Netw Learn Syst ; 31(2): 464-474, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-30990195

RESUMEN

We trained two spiking neural networks (SNNs), the cortical spiking network (CSN) and the cortical neuron-astrocyte network (CNAN), using a spike-based unsupervised method, on the MNIST and alpha-digit data sets and achieve an accuracy of 96.1% and 77.35%, respectively. We then connected CNAN to CSN by preserving maximum synchronization between them thanks to the concept of prolate spheroidal wave functions (PSWF). As a result, CSN receives additional information from CNAN without retraining. The important outcome is that CSN reaches 70.57% correct classification rate on capital letters without being trained on them. The overall contribution of transfer is 87.47%. We observed that for CSN the classifying neurons that relate to digits 0-9 of the alpha-digit data set are completely supported by the ones that relate to digits 0-9 of the MNIST data set. This means that CSN recognizes the similarity between the digits of the MNIST and alpha-digit data sets and classifies each digit of both data sets in the same class.


Asunto(s)
Astrocitos/fisiología , Corteza Cerebral/fisiología , Redes Neurales de la Computación , Neuronas/fisiología , Reconocimiento de Normas Patrones Automatizadas , Potenciales de Acción , Algoritmos , Ritmo alfa , Simulación por Computador , Sincronización de Fase en Electroencefalografía , Humanos , Aprendizaje Automático
13.
Chem Sci ; 10(35): 8135-8142, 2019 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-31857880

RESUMEN

Lignin depolymerization could provide an attractive renewable aromatic feedstock for the chemical industry. Past studies have suggested that lignin structural features such as ether content are correlated to lignin's upgradeability. An obstacle to the development of a conclusive causal relationship between lignin structure and upgradeability has been the difficulty to quantitatively measure lignin structural features. Here, we demonstrated that a modified HSQC-NMR method known as HSQC0 can accurately quantify lignin functionalities in extracted lignin using several synthetic polymer models. We then prepared a range of isolated lignin samples with a wide range of ether contents (6-46%). By using a simple ether cleavage model, we were able to predict final depolymerization yields very accurately (<4% error), conclusively demonstrating the direct causal relationship between ether content and lignin activity. The accuracy of this model suggests that, unlike in native lignin, ether linkages no longer appear to be randomly distributed in isolated lignin.

14.
Nat Protoc ; 14(3): 921-954, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30778206

RESUMEN

Lignin is one of the most promising sources of renewable aromatic hydrocarbons. Current methods for its extraction from lignocellulosic biomass-which include the kraft, sulfite, and organosolv processes-result in the rapid formation of carbon-carbon bonds, leading to a condensed lignin that cannot be effectively depolymerized into its constituent monomers. Treatment of lignocellulosic biomass with aldehydes during lignin extraction generates an aldehyde-stabilized lignin that is uncondensed and can be converted into its monomers at near-theoretical yields. Here, we outline an efficient, reproducible, and scalable process for extracting and purifying this aldehyde-stabilized lignin as a solid, which can easily be re-dissolved in an organic solvent. Upon exposure to hydrogenolysis conditions, this material provides near-theoretical yields of aromatic monomers (~40-50% of the Klason lignin for a typical hardwood). Cellulose and hemicellulose are also efficiently fractionated. This protocol requires 6-7 h for the extraction of the stabilized lignin and a basic proficiency in synthetic chemistry.


Asunto(s)
Aldehídos/química , Biomasa , Lignina/metabolismo , Fraccionamiento Químico , Hidrógeno , Lignina/química , Madera/química
15.
Int J Cardiol Heart Vasc ; 21: 74-77, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30364662

RESUMEN

AIMS: Atherosclerosis and ischemic heart disease are more common in diabetic patients. Atherosclerosis process can disturb the normal functioning of the vascular endothelium and increase vessel wall thickness. The aim of this study was the comparison of Carotid intima-media thickness (CIMT) with Exercise tolerance test as an alternative way to evaluate cardiac ischemia in diabetic patients. METHODS: In a cross-sectional study, 30 diabetic patients with positive exercise test and 30 diabetic patients with negative exercise test were enrolled. CIMT of the carotid artery in both groups of patients was measured. RESULT: CIMT in the patients with positive and negative exercise test were 1.04 ±â€¯0.21 mm and 0.61 ±â€¯0.11 mm, respectively (P < 0.001). CIMT in positive exercise test group was positively associated with age and negatively associated with gender, FBS, HDL and LDL cholesterol and in negative exercise group was negatively associated with gender, age, FBS, HDL and LDL cholesterol. CONCLUSION: Considering observed significant positive association between CIMT with result of exercise tolerance test (ETT) in type 2 diabetic patients, it may possible to use CIMT as an inexpensive and non-invasive method for evaluation of ischemic heart disease in diabetic patients.

16.
Nat Chem ; 10(12): 1222-1228, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30224685

RESUMEN

Polysaccharide depolymerization is an essential step for valorizing lignocellulosic biomass. In inexpensive systems such as pure water or dilute acid mixtures, carbohydrate monomer degradation rates exceed hemicellulose-and especially cellulose-depolymerization rates at most easily accessible temperatures, limiting sugar yields. Here, we use a reversible stabilization of xylose and glucose by acetal formation with formaldehyde to alter this kinetic paradigm, preventing sugar dehydration to furans and their subsequent degradation. During a harsh organosolv pretreatment in the presence of formaldehyde, over 90% of xylan in beech wood was recovered as diformylxylose (compared to 16% xylose recovery without formaldehyde). The subsequent depolymerization of cellulose led to carbohydrate yields over 70% and a final concentration of ~5 wt%, whereas the same conditions without formaldehyde gave a yield of 28%. This stabilization strategy pushes back the longstanding kinetic limits of polysaccharide depolymerization and enables the recovery of biomass-derived carbohydrates in high yields and concentrations.


Asunto(s)
Carbohidratos/química , Polimerizacion , Polisacáridos/química , Cinética , Estructura Molecular , Polisacáridos/síntesis química
17.
Maturitas ; 115: 74-83, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30049351

RESUMEN

Phytoestrogen-based medications are commonly used by menopausal women, and especially by obese postmenopausal women, to relieve menopausal symptoms. Substitution of animal with soy protein is often used in weight loss regimens, yet the effect of phytoestrogens, the main constituent of soy foods, on body composition is not completely understood. We conducted a systematic review and meta-analysis to investigate the associations between phytoestrogen supplementation and body weight and the main parameters of body composition in postmenopausal women. A literature search was done using 5 electronic databases from inception to April 2018. Randomized controlled trials (RCTs) with postmenopausal women comparing phytoestrogen supplementation followed by usual diet and placebo were included in the present meta-analysis. From 5932 references, we identified 23 RCTs that met our inclusion criteria, with a total of 1880 postmenopausal women. No association was observed between phytoestrogen supplementation and body weight, body mass index, waist and hip circumference, total fat mass or percentage of body fat. However, the use of phytoestrogens supplementation was associated with a slight decrease in waist-hip ratio; the pooled mean difference was -0.01 cm (95%CI: -0.01 to -0.006). In subgroup analysis, we found a modest decrease in body weight with phytoestrogens supplementation compared with placebo in healthy postmenopausal women [pooled mean difference of changes -0.28 kg (95%CI: -0.52 to -0.04)] and in RCTs with a median number of participants of 66 or less [pooled mean difference of changes -0.49 kg (95%CI: -0.87 to -0.11)]. In contrast, phytoestrogen supplementation was associated with increased body weight in postmenopausal women with preexisting metabolic disorders (prediabetes, type 2 diabetes, prehypertension and hyperlipidemia) [pooled mean difference of changes: 0.78 kg (95%CI: 0.53-1.03)]. In addition, there were some indications that some types of phytoestrogens, such as daidzein, but not soy products or isoflavone mix, could lead to modest adverse changes in body composition in menopausal women. Therefore, future studies should investigate the potential adverse effects of phytoestrogen supplementation on body composition among postmenopausal women.


Asunto(s)
Composición Corporal/efectos de los fármacos , Suplementos Dietéticos , Fitoestrógenos/uso terapéutico , Posmenopausia , Femenino , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
18.
Eur Neurol ; 79(1-2): 82-85, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29275418

RESUMEN

BACKGROUND: The effect of opium addiction (OA) on cerebrovascular disease is controversial. The aim of this study was to clarify this relationship in Iranian patients with ischemic stroke. METHODS: In a case-control study, 672 patients with ischemic stroke and 293 controls without a previous history of cerebrovascular or cardiovascular diseases were compared. OA as well as other risk factors such as diabetes mellitus (DM), hypertension (HTN), hyperlipidemia, tobacco smoking (TS) were compared between the 2 groups. RESULTS: OA percentage, TS, TS amount (pack/year), HTN and DM history were significantly higher in the case group compared to controls (p < 0.05). After regression analysis between risk factors, a significant difference remained between 2 groups with regards to HTN (OR 4.21, 95% CI 3.05-5.81, p < 0.001), TS (OR 2.33, 95% CI 1.51-3.59, p < 0.001), and OA (OR 2.36, 95% CI 1.16-4.85, p = 0.018). CONCLUSION: Our study showed OA is a risk factor for stroke. However, a follow-up study with a larger cohort is required to confirm the results.


Asunto(s)
Adicción al Opio/complicaciones , Accidente Cerebrovascular/etiología , Adulto , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Irán , Masculino , Persona de Mediana Edad , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
19.
Angew Chem Int Ed Engl ; 57(5): 1356-1360, 2018 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-29210487

RESUMEN

Protection groups were introduced during biomass pretreatment to stabilize lignin's α,γ-diol group during its extraction and prevent its condensation. Acetaldehyde and propionaldehyde stabilized the α,γ-diol without any aromatic ring alkylation, which significantly increased final product selectivity. The subsequent hydrogenolysis catalyzed by Pd/C generated lignin monomers at near-theoretical yields based on Klason lignin (48 % from birch, 20 % from spruce, 70 % from high-syringyl transgenic poplar), and with high selectivity to a single 4-n-propanolsyringol product (80 %) in the case of the poplar. Unlike direct hydrogenation of native wood, hydrogenolysis of protected lignin with Ni/C also led to high selectivity to this single product (78 %), paving the way to high-selectivity lignin upgrading with base metal catalysts. The use of extracted lignin facilitated valorization of polysaccharides, leading to high yields of all three major biomass polymers to a single major product.

20.
J Clin Diagn Res ; 11(7): SC01-SC04, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28892989

RESUMEN

INTRODUCTION: Lead is one of the toxic metals that can cause several complications in children. AIM: This study was conducted to determine Blood Lead Levels (BLLs) in healthy children and its association with individual and environmental factors. MATERIALS AND METHODS: This descriptive-analytical study was conducted on 262 healthy children aged 2-6 years in Shahrekord, Southwest Iran in 2013. After taking serum samples from the children, the checklists of effective environmental factors on lead toxicity were completed after interviewing the parents. BLLs were determined by ICP-MS. Data were analysed by descriptive and analytical statistics (chi-square and ANOVA) in SPSS 16. RESULTS: BLLs ranged 0.4-52.8 (mean: 6.9±7.9) ng/ml. BLL was significantly associated with father's education level, house colour damage, canned food use and soil eating (p<0.05), but not with age, gender, economic status, proximity to factory and kohl use (p>0.05). CONCLUSION: BLL can cause serious health risks for children in Shahrekord and is associated with certain risk factors. It is necessary to screen for these risk factors.

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