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1.
Int J Mol Sci ; 25(8)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38673848

RESUMEN

Alzheimer's disease is associated with protein aggregation, oxidative stress, and the role of acetylcholinesterase in the pathology of the disease. Previous investigations have demonstrated that geniposide and harpagoside protect the brain neurons, and cerium nanoparticles (CeO2 NPs) have potent redox and antioxidant properties. Thus, the effect of nanoparticles of Ce NPs and geniposide and harpagoside (GH/CeO2 NPs) on ameliorating AD pathogenesis was established on AlCl3-induced AD in mice and an aggregation proteins test in vitro. Findings of spectroscopy analysis have revealed that GH/CeO2 NPs are highly stable, nano-size, spherical in shape, amorphous nature, and a total encapsulation of GH in cerium. Treatments with CeO2 NPs, GH/CeO2 NPs, and donepezil used as positive control inhibit fibril formation and protein aggregation, protect structural modifications in the BSA-ribose system, have the ability to counteract Tau protein aggregation and amyloid-ß1-42 aggregation under fibrillation condition, and are able to inhibit AChE and BuChE. While the GH/CeO2 NPs, treatment in AD induced by AlCl3 inhibited amyloid-ß1-42, substantially enhanced the memory, the cognition coordination of movement in part AD pathogenesis may be alleviated through reducing amyloidogenic pathway and AChE and BuChE activities. The findings of this work provide important comprehension of the chemoprotective activities of iridoids combined with nanoparticles. This could be useful in the development of new therapeutic methods for the treatment of neurodegenerative diseases.


Asunto(s)
Acetilcolinesterasa , Enfermedad de Alzheimer , Cerio , Iridoides , Fármacos Neuroprotectores , Cerio/química , Cerio/farmacología , Iridoides/farmacología , Iridoides/química , Animales , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Acetilcolinesterasa/metabolismo , Péptidos beta-Amiloides/metabolismo , Masculino , Nanopartículas/química , Nanopartículas del Metal/química , Modelos Animales de Enfermedad
2.
Eur Child Adolesc Psychiatry ; 32(5): 881-892, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-34854985

RESUMEN

Calls for refining the understanding of depression beyond diagnostic criteria have been growing in recent years. We examined the prevalence and relevance of DSM and non-DSM depressive symptoms in two Brazilian school-based adolescent samples with two commonly used scales, the Patient Health Questionnaire (PHQ-A) and the Mood and Feelings Questionnaire (MFQ). We analyzed cross-sectional data from two similarly recruited samples of adolescents aged 14-16 years, as part of the Identifying Depression Early in Adolescence (IDEA) study in Brazil. We assessed dimensional depressive symptomatology using the PHQ-A in the first sample (n = 7720) and the MFQ in the second sample (n = 1070). We conducted network analyses to study symptom structure and centrality estimates of the two scales. Additionally, we compared centrality of items included (e.g., low mood, anhedonia) and not included in the DSM (e.g., low self-esteem, loneliness) in the MFQ. Sad mood and worthlessness items were the most central items in the network structure of the PHQ-A. In the MFQ sample, self-hatred and loneliness, two non-DSM features, were the most central items and DSM and non-DSM items in this scale formed a highly interconnected network of symptoms. Furthermore, analysis of the MFQ sample revealed DSM items not to be more frequent, severe or interconnected than non-DSM items, but rather part of a larger network of symptoms. A focus on symptoms might advance research on adolescent depression by enhancing our understanding of the disorder.


Asunto(s)
Anhedonia , Depresión , Humanos , Adolescente , Depresión/diagnóstico , Depresión/epidemiología , Estudios Transversales , Brasil/epidemiología
3.
Nonlinear Dyn ; 111(7): 6773-6789, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36465277

RESUMEN

Recently, chaotic maps have been considered to design pseudorandom number generator (PRNG). However, some chaotic maps present security disadvantages, such as low uniformity and low randomness properties. Nowadays, chaos-based PRNGs are used as the main source for the development of cryptographic algorithms. In this work, to overcome such weaknesses, a novel 2D hyperchaotic map is proposed based on discrete-time feedback by using Hénon map and Sine map. In addition, the dynamics of the hyperchaotic map are enhanced by using the remainder after division function (rem), where better random statistical properties are obtained. A comparison is made between the enhanced Hénon-Sine hyperchaotic map (EHSHM) and the Hénon-Sine hyperchaotic map through Lyapunov exponent analysis, attractor trajectory, histograms and sensitivity at initialization. Then, 8-bit pseudorandom number generator based on the proposed hyperchaotic map (PRNG-EHSHM) is designed and the initial seed of the PRNG is calculated by a secret key of 60 hexadecimal characters. It is implemented in both MATLAB and Arduino Mega microcontroller for experimental results. A complete security analysis is presented from a cryptographic point of view, such as key space, floating frequency, histograms and entropy of the information. Moreover, the randomness is verified with the tests of the National Institute of Standards and Technology (NIST 800-22). Based on the security results obtained, the proposed PRNG-EHSHM can be implemented in embedded cryptographic applications based on chaos.

4.
Entropy (Basel) ; 25(5)2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37238462

RESUMEN

In this work, the problem of master-slave outer synchronization in different inner-outer network topologies is presented. Specifically, the studied inner-outer network topologies are coupled in master-slave configuration, where some particular scenarios concerning inner-outer topologies are addressed in order to disclose a suitable coupling strength to achieve outer synchronization. The novel MACM chaotic system is used as a node in the coupled networks, which presents robustness in its bifurcation parameters. Extensive numerical simulations are presented where the stability of the inner-outer network topologies is analyzed through a master stability function approach.

5.
Sensors (Basel) ; 22(3)2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-35161955

RESUMEN

Childhood obesity causes not only medical and psychosocial problems, it also reduces the life expectancy of the adults that they will become. On a large scale, obese adults adversely affect labor markets and the gross domestic product of countries. Monitoring the growth charts of children helps to maintain their body weight within healthy parameters according to the World Health Organization. Modern technologies allow the use of telehealth to carry out weight control programs and monitoring to verify children's compliance with the daily recommendations for risk factors that can be promoters of obesity, such as insufficient physical activity and insufficient sleep hours. In this work, we propose a secure remote monitoring and supervision scheme of physical activity and sleep hours for the children based on telehealth, multi-user networks, chaotic encryption, and spread spectrum, which, to our knowledge, is the first attempt to consider this service for safe pediatric telemedicine. In experimental results, we adapted a recent encryption algorithm in the literature for the proposed monitoring scheme using the assessment of childhood obesity as an application case in a multi-user network to securely send and receive fictitious parameters on childhood obesity of five users through the Internet by using just one communication channel. The results show that all the monitored parameters can be transmitted securely, achieving high sensitivity against secret key, enough secret key space, high resistance against noise interference, and 4.99 Mb/sec in computational simulations. The proposed scheme can be used to monitor childhood obesity in secure telehealth application.


Asunto(s)
Obesidad Infantil , Telemedicina , Adulto , Algoritmos , Niño , Ejercicio Físico , Humanos , Monitoreo Fisiológico , Obesidad Infantil/prevención & control
6.
Psychol Health Med ; 27(1): 257-264, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33586546

RESUMEN

This work constitutes an exploratory study during the second and third phases of COVID-19 in Mexico, characterized by local transmission and untraceable cases, respectively, with an incidental sample of 666 participants. The 21-item Depression Anxiety Stress Scale was used to assess depression, anxiety and stress associated to COVID-19. Additionally, the Impact of the Event Scale-Revised was applied to assess the impact of the event, and the 10-item Connor-Davidson Resilience Scale was employed to assess resilience. Participants' levels of traumatic impact (21.7%), severe depression (7%), severe anxiety (9.4%) and severe stress (5.4%) were revealed to be lower than other populations. Comparison of means and effect size η2p of the data shows that women and young people (18-39 years) suffer the greatest negative effects. Individuals with higher levels of resilience experience fewer psychological consequences confirming its importance in the face of the adversities. These findings provide valuable information on the impact of COVID-19 pandemic in the Mexican population, allowing a comparative analysis at an international level which can be helpful in the development of appropriate sanitary policies.


Asunto(s)
COVID-19 , Resiliencia Psicológica , Adolescente , Ansiedad/epidemiología , Depresión/epidemiología , Femenino , Humanos , México/epidemiología , Pandemias , SARS-CoV-2 , Estrés Psicológico/epidemiología
7.
Molecules ; 27(17)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36080407

RESUMEN

The absence of a treatment efficient in the control of type 2 diabetes mellitus requires more functional products to assist treatment. Luteolin (LU) and diosmin (DIO) have been known as bioactive molecules with potential for the treatment of diabetes. This work aimed to establish the role that a combination of LU and DIO in selenium nanoparticles (SeNPs) played in streptozotocin (STZ)- induced diabetes mice. Green synthesis of Se NPs was performed by mixing luteolin and diosmin with the solution of Na2SeO3 under continuous stirring conditions resulting in the flavonoids conjugated with SeNPs. The existence of flavonoids on the surface of SeNPs was confirmed by UV-Vis spectra, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) images, and DLS graphs via Zetasizer. The average diameter of GA/LU/DIO-SeNPs was 47.84 nm with a PDI of -0.208, a zeta potential value of -17.6, a Se content of 21.5% with an encapsulation efficiency of flavonoids of 86.1%, and can be stabilized by gum Arabic for approximately 175 days without any aggregation and precipitation observed at this time. Furthermore, The C57BL/6 mice were treated with STZ induced-diabetes and were exposed to LU/DIO, SeNPs, and GA/LU/DIO-SeNPs for six weeks. The treatment by nanospheres (GA/LU/DIO-SeNPs) in the mice with diabetes for a period of 6 weeks restored their blood glucose, lipid profile, glycogen, glycosylated hemoglobin, and insulin levels. At the same time, there were significant changes in body weight, food intake, and water intake compared with the STZ- untreated induced diabetic mice. Moreover, the GA/LU/DIO-SeNPs showed good antioxidant activity examined by catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) in liver and kidney and can prevent the damage in the liver evaluated by aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) activities. The nanospheres exhibited a significant anti-diabetic activity with a synergistic effect between the selenium and flavonoids. This investigation provides novel SeNPs nanospheres prepared by a high-efficiency strategy for incorporating luteolin and diosmin to improve the efficiency in type 2 diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Diosmina , Nanopartículas , Selenio , Animales , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Luteolina/farmacología , Ratones , Ratones Endogámicos C57BL , Nanopartículas/química , Selenio/química , Estreptozocina
8.
Chembiochem ; 22(3): 516-522, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-32974990

RESUMEN

Indoleamine-2,3-dioxygenase 1 (IDO1) is a heme-containing enzyme that catalyzes the rate-limiting step in the kynurenine pathway of tryptophan (TRP) metabolism. As it is an inflammation-induced immunoregulatory enzyme, pharmacological inhibition of IDO1 activity is currently being pursued as a potential therapeutic tool for the treatment of cancer and other disease states. As such, a detailed understanding of the mechanism of action of IDO1 inhibitors with various mechanisms of inhibition is of great interest. Comparison of an apo-form-binding IDO1 inhibitor (GSK5628) to the heme-coordinating compound, epacadostat (Incyte), allows us to explore the details of the apo-binding inhibition of IDO1. Herein, we demonstrate that GSK5628 inhibits IDO1 by competing with heme for binding to a heme-free conformation of the enzyme (apo-IDO1), whereas epacadostat coordinates its binding with the iron atom of the IDO1 heme cofactor. Comparison of these two compounds in cellular systems reveals a long-lasting inhibitory effect of GSK5628, previously undescribed for other known IDO1 inhibitors. Detailed characterization of this apo-binding mechanism for IDO1 inhibition might help design superior inhibitors or could confer a unique competitive advantage over other IDO1 inhibitors vis-à-vis specificity and pharmacokinetic parameters.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Inhibidores Enzimáticos/química , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Conformación Molecular
9.
Eur J Clin Microbiol Infect Dis ; 39(1): 131-138, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31529305

RESUMEN

To identify the prevalence of C. albicans in primary endodontic infections of type two diabetes mellitus (T2DM) patients and compare their clinical and radiographical characteristics with a non-diabetic control group, establishing the possible relationship between primary endodontic infection, T2DM, and C. albicans, since diabetes mellitus (DM), influences the development, course, and response to the treatment of apical periodontitis, but the presence of Candida albicans (C. albicans) has not been considered before. A total of 120 patients were selected and divided into two groups: 60 T2DM diagnosed patients and 60 non-diabetic controls. A clinical examination and radiographic analysis were performed to establish a periapical index score (PAI). Root canal samples were taken. Deoxyribonucleic acid (DNA) was extracted, and specific primers were used to identify C. albicans by polymerase chain reaction (PCR). A twofold increase in the prevalence of C. albicans in T2DM patients was observed in contrast to control patients (p = 0.0251). Sixty-five percent of T2DM patients with positive C. albicans scored a ≥ 3 PAI, while only 27% of the patients without C. albicans had a ≥ 3 PAI score (p = 0.0065). Long-term DM patients presented C. albicans more frequently (p < 0.0001). In this study, long-term T2DM patients carried C. albicans in their root canals more frequently when having a primary endodontic infection. Furthermore, this C. albicans presence seems to be related to a higher frequency of apical periodontitis.


Asunto(s)
Candidiasis/epidemiología , Complicaciones de la Diabetes/microbiología , Periodontitis Periapical/microbiología , Pulpitis/microbiología , Adulto , Anciano , Candida albicans/aislamiento & purificación , Estudios Transversales , Cavidad Pulpar/microbiología , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Periodontitis Periapical/epidemiología , Prevalencia , Estudios Prospectivos , Pulpitis/epidemiología , Adulto Joven
10.
J Asian Nat Prod Res ; 22(7): 603-617, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31322002

RESUMEN

This present study was to evaluate the protein tyrosine phosphatase 1B (PTP1B) inhibitory activity of nine diterpenes isolated from seeds of Phalaris canariensis, as well as their effect on streptozotocin-nicotinamide-induced type 2 diabetic mice. Their structures were established by spectroscopic analyses. Diterpenes, 1, 4, and 2 exhibited the strongest inhibitory activity on PTP1B with IC50 values of 6.9, 7.3, and 6.5 µM, respectively, The administration of 1-9 showed significant effect on hyperglycemia, among them 1, 4, and 2 reduced fasting glucose levels (55.65%, 54.27%, and 51.22%, respectively). Results revealed that diterpenes performed potential antidiabetic activity via inhibition of PTP1B.[Formula: see text].


Asunto(s)
Diabetes Mellitus Experimental , Diterpenos , Phalaris , Animales , Hipoglucemiantes , Ratones , Estructura Molecular , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Semillas , Estreptozocina
11.
Psychol Health Med ; 25(7): 879-886, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31661972

RESUMEN

OBJECTIVE: To measure personal, medical and psychological positive and negative variables and to determine their relation with somatization in a sample of health sciences students. Subjects and methods: A total of 594 (34.43%) of the 1725 health science students of a public university answered an online survey with personal and medical information as well as the following psychological variables: phsychological well-being, five facets mindfulness questionnaire (FFMQ), life satisfaction, depression, and academic stress. Additionally, the presence of 11 somatic symptoms and 11 diseases during the last year was measured. Results: Most students were women (74.06%) who were 19.96 ± 4.28 years old. The global frequency of somatization in the previous year was 66.59%, and the presence of any measured disease 14.75%. With the multivariate analysis, self-acceptance was the most related variable (negatively) with somatization, followed by the sum of diseases, female gender, academic stress, smoking, and depression, in a model with an R-value of 0.634, self-acceptance was also the most related variable (negatively) with depression, being this last the most related variable with academic stress. Conclusions: After analyzing all variables considered in this study, self-acceptance was the most related variable with somatization and depression; this highlights the importance of strengthening the acceptance of the self in the student population in order to prevent these conditions and their consequences.


Asunto(s)
Depresión/psicología , Atención Plena , Autoimagen , Trastornos Somatomorfos/psicología , Estrés Psicológico/psicología , Estudiantes del Área de la Salud/psicología , Adolescente , Adulto , Femenino , Humanos , Masculino , Universidades , Adulto Joven
12.
BMC Cancer ; 19(1): 708, 2019 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-31319816

RESUMEN

BACKGROUND: Mexico City has one of the highest incidences and mortality rates of acute lymphoblastic leukemia (ALL) in the world and a high frequency of early relapses (17%) and early mortality (15%). Otherwise, childhood overweight and obesity are reaching epidemic proportions. They have been associated with poor outcomes in children with ALL. The aim of present study was to identify if overweight and obesity are predictors of early mortality and relapse in Mexican children with ALL. METHODS: A multicenter cohort study was conducted. ALL children younger than 15 years old were included and followed-up during the first 24 months after diagnosis. Overweight and obesity were classified according World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) criteria. Early mortality and early relapses were the main outcomes. RESULTS: A total of 1070 children were analyzed. Overweight/obesity at diagnosis were predictors of early mortality (WHO: HR = 1.4, 95%CI:1.0-2.0; CDC: HR = 1.6, 95%CI:1.1-2.3). However, no associations between overweight (WHO: HR = 1.5, 95%CI:0.9-2.5; CDC: HR = 1.0; 95% CI:0.6-1.6) and obesity (WHO: HR = 1.5, 95%CI:0.7-3.2; CDC: HR = 1.4; 95%CI:0.9-2.3) with early relapse were observed. CONCLUSIONS: Overweight and obese patients embody a subgroup with high risk of dying during leukemia treatment.


Asunto(s)
Obesidad Infantil/epidemiología , Obesidad Infantil/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Adolescente , Índice de Masa Corporal , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Masculino , México/epidemiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Pronóstico , Recurrencia
13.
Int J Mol Sci ; 20(10)2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-31096545

RESUMEN

Acute lymphoblastic leukemia is the most common type of childhood cancer worldwide. Mexico City has one of the highest incidences and mortality rates of this cancer. It has previously been recognized that chromosomal translocations are important in cancer etiology. Specific fusion genes have been considered as important treatment targets in childhood acute lymphoblastic leukemia (ALL). The present research aimed at the identification and characterization of novel fusion genes with potential clinical implications in Mexican children with acute lymphoblastic leukemia. The RNA-sequencing approach was used. Four fusion genes not previously reported were identified: CREBBP-SRGAP2B, DNAH14-IKZF1, ETV6-SNUPN, ETV6-NUFIP1. Although a fusion gene is not sufficient to cause leukemia, it could be involved in the pathogenesis of the disease. Notably, these new translocations were found in genes encoding for hematopoietic transcription factors which are known to play an important role in leukemogenesis and disease prognosis such as IKZF1, CREBBP, and ETV6. In addition, they may have an impact on the prognosis of Mexican pediatric patients with ALL, with the potential to be included in the current risk stratification schemes or used as therapeutic targets.


Asunto(s)
Proteínas de Fusión Oncogénica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocación Genética/genética , Adolescente , Adulto , Proteína de Unión a CREB/genética , Niño , Preescolar , Dineínas/genética , Femenino , Proteínas Activadoras de GTPasa/genética , Regulación Neoplásica de la Expresión Génica , Reordenamiento Génico , Humanos , Factor de Transcripción Ikaros/genética , Lactante , Masculino , México , Proteínas Nucleares/genética , Pronóstico , Proteínas Proto-Oncogénicas c-ets/genética , Proteínas de Unión a Caperuzas de ARN/genética , Proteínas de Unión al ARN/genética , Receptores Citoplasmáticos y Nucleares/genética , Proteínas Represoras/genética , Adulto Joven , Proteína ETS de Variante de Translocación 6
14.
Molecules ; 24(7)2019 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-30925713

RESUMEN

Previous studies have shown that accumulation of advanced glycation end products (AGEs) can be the cause of diabetic nephropathy (DN) in diabetic patients. Dihydrochalcone 3'-O-ß-d-glucopyranosyl α,4,2',4',6'-pentahydroxy⁻dihydrochalcone (1) is a powerful antiglycation compound previously isolated from Eysenhardtia polystachya. The aim was to investigate whether (1) was able to protect against diabetic nephropathy in streptozotocin (STZ)-induced diabetic mice, which displayed renal dysfunction markers such as body weight, creatinine, uric acid, serum urea, total urinary protein, and urea nitrogen in the blood (BUN). In addition, pathological changes were evaluated including glycated hemoglobin (HbA1c), advanced glycation end products (AGEs) in the kidney, as well as in circulation level and pro-inflammatory markers ICAM-1 levels in diabetic mice. After 5 weeks, these elevated markers of dihydrochalcone treatment (25, 50 and 100 mg/kg) were significantly (p < 0.05) attenuated. In addition, they ameliorate the indices of renal inflammation as indicated by ICAM-1 markers. The kidney and circulatory AGEs levels in diabetic mice were significantly (p < 0.05) attenuated by (1) treatment. Histological analysis of kidney tissues showed an important recovery in its structure compared with the diabetic group. It was found that the compound (1) attenuated the renal damage in diabetic mice by inhibiting AGEs formation.


Asunto(s)
Chalconas/uso terapéutico , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/tratamiento farmacológico , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/tratamiento farmacológico , Fabaceae/química , Productos Finales de Glicación Avanzada/sangre , Corteza de la Planta/química , Animales , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Chalconas/síntesis química , Chalconas/química , Chalconas/farmacología , Creatinina/sangre , Nefropatías Diabéticas/patología , Ingestión de Líquidos , Conducta Alimentaria , Glucosa/metabolismo , Hemoglobina Glucada/metabolismo , Mediadores de Inflamación/metabolismo , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Ratones Endogámicos C57BL , Niacinamida , Tamaño de los Órganos/efectos de los fármacos , Ratas , Estreptozocina , Urea/sangre , Ácido Úrico/sangre , Orina
15.
Entropy (Basel) ; 21(8)2019 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-33267528

RESUMEN

Currently, chaos-based cryptosystems are being proposed in the literature to provide confidentiality for digital images, since the diffusion effect in the Advance Encryption Standard (AES) algorithm is weak. Security is the most important challenge to assess in cryptosystems according to the National Institute of Standard and Technology (NIST), then cost and performance, and finally algorithm and implementation. Recent chaos-based image encryption algorithms present basic security analysis, which could make them insecure for some applications. In this paper, we suggest an integral analysis framework related to comprehensive security analysis, cost and performance, and the algorithm and implementation for chaos-based image cryptosystems. The proposed guideline based on 20 analysis points can assist new cryptographic designers to present an integral analysis of new algorithms. Future comparisons of new schemes can be more consistent in terms of security and efficiency. In addition, we present aspects regarding digital chaos implementation, chaos validation, and key definition to improve the security of the overall cryptosystem. The suggested guideline does not guarantee security, and it does not intend to limit the liberty to implement new analysis. However, it provides for the first time in the literature a solid basis about integral analysis for chaos-based image cryptosystems as an effective approach to improve security.

16.
Medicina (Kaunas) ; 55(10)2019 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-31547185

RESUMEN

Background and Objectives: The knowledge that the cholinergic neurons from pedunculopontine nucleus (PPN) are vulnerable to the degeneration in early stages of the Parkinson disease progression has opened new perspectives to the development of experimental model focused in pontine lesions that could increase the risk of nigral degeneration. In this context it is known that PPN lesioned rats exhibit early changes in the gene expression of proteins responsible for dopaminergic homeostasis. At the same time, it is known that nicotinic cholinergic receptors (nAChRs) mediate the excitatory influence of pontine-nigral projection. However, the effect of PPN injury on the expression of transcription factors that modulate dopaminergic neurotransmission in the adult brain as well as the α7 nAChRs gene expression has not been studied. The main objective of the present work was the study of the effects of the unilateral neurotoxic lesion of PPN in nuclear receptor-related factor 1 (Nurr1), paired-like homeodomain transcription factor 3 (Pitx3), and α7 nAChRs mRNA expression in nigral tissue. Materials and Methods: The molecular biology studies were performed by means of RT-PCR. The following experimental groups were organized: Non-treated rats, N-methyl-D-aspartate (NMDA)-lesioned rats, and Sham operated rats. Experimental subjects were sacrificed 24 h, 48 h and seven days after PPN lesion. Results: Nurr1 mRNA expression, showed a significant increase both 24 h (p < 0.001) and 48 h (p < 0.01) after PPN injury. Pitx3 mRNA expression evidenced a significant increase 24 h (p < 0.001) followed by a significant decrease 48 h and seven days after PPN lesion (p < 0.01). Finally, the α7 nAChRs nigral mRNA expression remained significantly diminished 24 h, 48 h (p < 0.001), and 7 days (p < 0.01) after PPN neurotoxic injury. Conclusion: Taking together these modifications could represent early warning signals and could be the preamble to nigral neurodegeneration events.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Proteínas de Homeodominio/metabolismo , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Enfermedad de Parkinson/metabolismo , Núcleo Tegmental Pedunculopontino/metabolismo , ARN Mensajero/metabolismo , Sustancia Negra/metabolismo , Factores de Transcripción/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Animales , Modelos Animales de Enfermedad , Proteínas de Homeodominio/genética , Masculino , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Enfermedad de Parkinson/patología , Núcleo Tegmental Pedunculopontino/patología , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/genética , Receptor Nicotínico de Acetilcolina alfa 7/genética
17.
J Nat Prod ; 80(7): 1955-1963, 2017 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-28704049

RESUMEN

2,4-Diacetylphloroglucinol (DAPG) (1) is a phenolic polyketide produced by some plant-associated Pseudomonas species, with many biological activities and ecological functions. Here, we aimed at reconstructing the natural history of DAPG using phylogenomics focused at its biosynthetic gene cluster or phl genes. In addition to around 1500 publically available genomes, we obtained and analyzed the sequences of nine novel Pseudomonas endophytes isolated from the antidiabetic medicinal plant Piper auritum. We found that 29 organisms belonging to six Pseudomonas species contain the phl genes at different frequencies depending on the species. The evolution of the phl genes was then reconstructed, leading to at least two clades postulated to correlate with the known chemical diversity surrounding DAPG biosynthesis. Moreover, two of the newly obtained Pseudomonas endophytes with high antiglycation activity were shown to exert their inhibitory activity against the formation of advanced glycation end-products via DAPG and related congeners. Its isomer, 5-hydroxyferulic acid (2), detected during bioactivity-guided fractionation, together with other DAPG congeners, were found to enhance the detected inhibitory activity. This report provides evidence of a link between the evolution and chemical diversity of DAPG and congeners.


Asunto(s)
Endófitos/química , Floroglucinol/análogos & derivados , Piper/microbiología , Plantas Medicinales/microbiología , Policétidos/aislamiento & purificación , Policétidos/farmacología , Pseudomonas/química , Ácidos Cumáricos/química , Ácidos Cumáricos/aislamiento & purificación , México , Estructura Molecular , Familia de Multigenes , Floroglucinol/química , Floroglucinol/aislamiento & purificación , Floroglucinol/farmacología , Piper/genética , Componentes Aéreos de las Plantas/química , Plantas Medicinales/genética , Policétidos/química , Estereoisomerismo
18.
Altern Ther Health Med ; 22(1): 8-14, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26773316

RESUMEN

CONTEXT: Obesity and its associated diseases are an increasing problem around the world. One hyperglycemic remedy is reduction of glucose absorption performed by suppressing digestion of carbohydrates and lipids through the use of inhibitors. Phalaris canariensis (P canariensis) is a species belonging to the Graminaceae family and is used in traditional medicine in Mexico for treatment of diabetes and obesity. OBJECTIVE: The aim of the study was to evaluate the effects of different extracts of the seeds of P canariensis on enzymes metabolizing fat and carbohydrates, obtained using 3 solvents. DESIGN: The seeds of P canariensis were extracted using hexane (ALH), chloroform (ALC), and methanol (ALM) and were investigated for their antiobesity potential. SETTING: This research was conducted in the Laboratory of Research of Natural Products in the School of Chemical Engineering at the National Polytechnic Institute and in the Research Laboratory of Enzymology in the National School of Biological Sciences. OUTCOME MEASURES: Different concentrations of the extracts were used to study the inhibition of enzymatic activity by porcine pancreatic α-amylase, with carbose as a positive control. The inhibitory activity of α-glucosidase was determined using the standard method with bovine serum albumin (BSA). Pancreatic lipase (PL) activity was measured by absorbance at 412 nm, and the data obtained were compared with orlistat. The PL activity was assessed using a second method measuring the rate of release of oleic acid from triolein. Lipoprotein lipase (LPL) activity was measured by released (3H)-oleic acid. Lipolytic activity in cultured, mouse, 3T3-Ll adipocytes was used as a measure of hormone-sensitive lipase activity. The inhibitory activity of rat intestinal sucrase was determined by measuring the glucose released. A Caco-2 cell assay determined the content of free glucose. RESULTS: The ALH extract of P canariensis showed potent inhibitory activity with IC50 values of 2.13 and 1.25 mg/mL as compared with α-amylase and α-glucosidase, respectively, and produced inhibition in rat intestinal sucrose. Further, the ALM extract showed significantly inhibitory effects against PL, LPL, and lipolysis of 3T3-LI adipocytes. CONCLUSIONS: The results provide evidence for the effects of the seeds of P canariensis for a retarded absorption of carbohydrates and lipids through the inhibition of enzymes that are related to obesity and diabetes mellitus type 2.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Obesidad/enzimología , Phalaris/química , Extractos Vegetales/farmacología , Semillas/química , Células 3T3 , Animales , Células CACO-2 , Inhibidores Enzimáticos/química , Humanos , Lipasa/efectos de los fármacos , Masculino , Ratones , Extractos Vegetales/química , Ratas , Solventes , Porcinos
19.
Gac Med Mex ; 152(Suppl 2): 66-77, 2016 Oct.
Artículo en Español | MEDLINE | ID: mdl-27792718

RESUMEN

INTRODUCTION: Acute myeloid leukemias represent the second most common childhood leukemia subtype. In Mexico, there are few studies on descriptive epidemiology for this disease. AIMS: To report acute myeloid leukemia incidence for children less than 15 years of age in the Metropolitan Area of the Valley of Mexico for a period of five years (2010-2014) and to analyze whether there are differences in the incidence of acute myeloid leukemia by regions. MATERIAL AND METHODS: A descriptive study was conducted in nine public hospitals in Mexico City. The crude annual average incidence rate and adjusted average annual incidence rate were calculated. RESULTS: A total of 190 patients with diagnosis of de novo acute myeloid leukemia were analyzed. Male sex (57.2%) and acute myeloid leukemia-M3 subtype (25.3%) were more frequent. The adjusted average annual incidence rates for Mexico City and for the Metropolitan Area of the Valley of Mexico were 8.18 and 7.74 per million children under 15 years old, respectively. CONCLUSIONS: It seems that childhood acute myeloid leukemia incidence is increasing in Mexico City, which makes the identification of associated risk factors imperative.


Asunto(s)
Leucemia Mieloide Aguda/epidemiología , Adolescente , Niño , Ciudades/epidemiología , Humanos , Incidencia , Lactante , Leucemia Mieloide Aguda/etiología , Masculino , México/epidemiología , Factores de Riesgo , Distribución por Sexo
20.
Pharm Biol ; 52(11): 1435-44, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25026338

RESUMEN

CONTEXT: Both oxidation and hyperglycemia cause increased glycation and the formation of advanced glycation end-products (AGEs) which underlie the complications of diabetes. OBJECTIVE: The goal of this article is to determine the effect of the chloroform extract from leaves of Azadirachta indica A. Juss; (Meliaceae) (AI) on the formation of glycated protein. MATERIALS AND METHODS: Chloroform extract was subjected to in vitro bioassays to evaluate advanced glycation end-products formation. Bovine serum albumin (BSA)-glucose, BSA-methylglyoxal, Amadori-rich protein, glycated hemoglobin, oxidation, and glycation of LDL were determined. Doses of AI of 200 mg/kg/d by oral gavage were administered once daily for 30 d, at streptozotocin-induced diabetic rats. After this period, renal damage (TBARS), glucose, methylglyoxal, glycolaldehyde, and tail tendon collagen were investigated. RESULTS AND DISCUSSION: AI exhibits protective action in BSA against glycation formation, GHb, protein levels, and LDL against glycation and oxidation. The renal glucose level decreases a 3.9 mg/g wet tissue. TBA-reactive substance showed a significant decrease to 1.82 mmol/mg protein. In addition, AI showed inhibitory activity against AGEs formation, methylglyoxal, and glycolaldehyde levels in kidney. Treatment with AI in rat tail tendon produced a reduction in cross-linking of collagen proteins. The antiglycation activities of A. indica were attributed in part to their antioxidant activity. AI alleviated oxidative stress under diabetic conditions through the inhibition of lipid peroxidation prevents the onset renal damage. CONCLUSION: We found that A. indica is an inhibitor AGE formation, and oxidative stress with a renoprotective effect, which are considered to play important roles in diabetic kidney disease.


Asunto(s)
Azadirachta , Diabetes Mellitus Experimental/tratamiento farmacológico , Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Animales , Bovinos , Diabetes Mellitus Experimental/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Masculino , Hojas de la Planta , Ratas , Ratas Wistar , Estreptozocina , Resultado del Tratamiento
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