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1.
Mol Carcinog ; 63(7): 1319-1333, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38629425

RESUMEN

Breast cancer is the most frequent neoplasia in developed countries and the leading cause of death in women worldwide. Epithelial-to-mesenchymal transition (EMT) is a cellular process through which epithelial cells decrease or lose their epithelial characteristics and gain mesenchymal properties. EMT mediates tumor progression, because tumor cells acquire the capacity to execute the multiple steps of invasion and metastasis. Benzo[a]pyrene (B[a]P) is an environmental organic pollutant generated during the burning of fossil fuels, wood, and other organic materials. B[a]P exposition increases the incidence of breast cancer, and induces migration and/or invasion in MDA-MB-231 and MCF-7 breast cancer cells. However, the role of B[a]P in the induction of an EMT process and metastasis of mammary carcinoma cells has not been studied in detail. In this study, we demonstrate that B[a]P induces an EMT process in MCF10A mammary non-tumorigenic epithelial cells. In addition, B[a]P promotes the formation of larger tumors in Balb/cJ mice inoculated with 4T1 cells than in untreated mice and treated with dimethyl sulfoxide (DMSO). B[a]P also increases the number of mice with metastasis to brain and the total number of brain metastatic nodules in Balb/cJ mice inoculated with 4T1 cells compared with untreated mice and treated with DMSO. In conclusion, B[a]P induces an EMT process in MCF10A cells and the growth of mammary tumors and metastasis to brain in Balb/cJ mice inoculated with 4T1 cells.


Asunto(s)
Benzo(a)pireno , Neoplasias Encefálicas , Transición Epitelial-Mesenquimal , Ratones Endogámicos BALB C , Animales , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Benzo(a)pireno/toxicidad , Humanos , Ratones , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/inducido químicamente , Neoplasias de la Mama/patología , Neoplasias de la Mama/inducido químicamente , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos
2.
Rev Invest Clin ; 76(1): 37-44, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38442374

RESUMEN

Background: Osteoarthritis is a frequent rheumatic disease. Some single-nucleotide polymorphisms of the gene associated with fat mass and obesity are associated with increased body mass index and knee osteoarthritis. Objective: The objective of this study was to analyze the association of single nucleotide polymorphism rs1477196 of the fat mass and obesity gene with primary knee osteoarthritis. Methods: This observational and cross-sectional study included 347 Mexican participants. We performed the genotypification analysis with TaqMan® probe C_2031262_10 for rs1477196 (Thermo Fisher Scientific). Multivariate analysis included covariables such as age, type 2 diabetes, obesity, and postmenopause. Results: Type 2 diabetes, obesity, and postmenopause were associated with primary knee osteoarthritis in female participants. We did not find an association between rs1477196 and obesity. In the codominant and dominant genetic models, rs1477196 was significantly associated with primary knee osteoarthritis only in the female group, including in the model adjusted by other covariables (odds ratio = 2.517; 1.035-6.123; p = 0.042 and odds ratio = 2.387; 1.054-5.407; p = 0.037, respectively). The interaction between rs1477196 and obesity was significantly associated with primary knee osteoarthritis in female participants (p = 0.039 and p = 0.043). Conclusions: Our findings suggest that the rs1477196 variant of the fat and obesity mass gene may be associated with the risk of primary knee osteoarthritis in women.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Diabetes Mellitus Tipo 2 , Osteoartritis de la Rodilla , Femenino , Humanos , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Estudios Transversales , México , Obesidad/epidemiología , Obesidad/genética , Osteoartritis de la Rodilla/epidemiología , Osteoartritis de la Rodilla/genética , Polimorfismo de Nucleótido Simple
3.
J Membr Biol ; 256(1): 79-90, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35751654

RESUMEN

Caveolae are small plasma membrane invaginations constituted for membrane proteins namely caveolins and cytosolic proteins termed cavins, which can occupy up to 50% of the surface of mammalian cells. The caveolae have been involved with a variety of cellular processes including regulation of cellular signaling. Insulin is a hormone that mediates a variety of physiological processes through activation of insulin receptor (IR), which is a tyrosine kinase receptor expressed in all mammalian tissues. Insulin induces activation of signal transducers and activators of transcription (STAT) family members including STAT5. In this study, we demonstrate, for the first time, that insulin induces phosphorylation of STAT5 at tyrosine-694 (STAT5-Tyr(P)694), STAT5 nuclear accumulation and an increase in STAT5-DNA complex formation in MCF-7 breast cancer cells. Insulin also induces nuclear accumulation of STAT5-Tyr(P)694, caveolin-1, and IR in MCF-7 cells. STAT5 nuclear accumulation and the increase of STAT5-DNA complex formation require the integrity of caveolae and microtubule network. Moreover, insulin induces an increase and nuclear accumulation of STAT5-Tyr(P)694 in MDA-MB-231 breast cancer cells. In conclusion, results demonstrate that caveolae and microtubule network play an important role in STAT5-Tyr(P)694, STAT5 nuclear accumulation and STAT5-DNA complex formation induced by insulin in breast cancer cells.


Asunto(s)
Neoplasias de la Mama , Caveolas , Animales , Humanos , Femenino , Caveolas/metabolismo , Insulina/farmacología , Insulina/metabolismo , Células MCF-7 , Factor de Transcripción STAT5/metabolismo , Neoplasias de la Mama/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Fosforilación , Tirosina/metabolismo , ADN/metabolismo , Mamíferos/metabolismo
4.
Psychol Health Med ; 28(4): 995-1003, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34579608

RESUMEN

The objective of the study is to determine the personal, behavioral and psychological variables associated with somatization and the number of diseases in each gender from a sample of Mexican general population. They answered a questionnaire of behavioral and psychological variables including somatization and the sum of 16 different diseases and any additional one, finally the body mass index (BMI) was measured. A total of 164 participants (women = 90, men = 74) were included. We observed that women had more somatization and number of diseases than men and that more variables (mainly psychological) were associated with somatization and with the number of diseases in women than in men. Among the variables most negatively correlated in women with both variables were sleep quality (r = -0.525 and r = -0.536, p < 0.001), self-acceptance (r = -0.460 and r = -0.501, p < 0.001), positive relations with others (r = -0.447 and r = -0.441 p < 0.001), environmental mastery (r = -0.414, p < 0.001, for both variables), purpose in life and optimism; while men only showed a low negative correlation between emotion regulation and the number of diseases (r = -0.289, p < 0.05). The positive associated variables in women were anxiety, negative emotions and depression; while men showed a lower correlation between these three variables only with somatization. The somatization and age were positively related to the number of diseases in both genders and the BMI was significantly associated with the number of diseases only in men. In conclusion, women had more somatization and number of diseases than men and also had more relation between psychological variables and the two dependent variables than men, which could in part explains the higher values of somatization and the number of diseases in women, considering that they usually present higher values of psychopathological variables.


Asunto(s)
Ansiedad , Depresión , Humanos , Masculino , Femenino , Ansiedad/epidemiología , Depresión/epidemiología , Depresión/psicología , Trastornos de Ansiedad , Encuestas y Cuestionarios
5.
Int J Mol Sci ; 24(19)2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37834042

RESUMEN

Multiple sclerosis (MS) is a chronic and demyelinating disease with an autoimmune origin, which leads to neurodegeneration and progressive disability. Approximately 30 to 50% of patients do not respond optimally to disease-modifying therapies (DMTs), and therapeutic response may be influenced by genetic factors such as genetic variants. Therefore, our study aimed to investigate the association of the HLA-DRB1*0403 genetic variant and therapeutic response to DMTs in MS. We included 105 patients with MS diagnosis. No evidence of disease activity based on the absence of clinical relapse, disability progression or radiological activity (NEDA-3) was used to classify the therapeutic response. Patients were classified as follows: (a) controls: patients who achieved NEDA-3; (b) cases: patients who did not achieve NEDA-3. DNA was extracted from peripheral blood leukocytes. HLA-DRB1*0403 genetic variant was analyzed by quantitative polymerase chain reaction (qPCR) using TaqMan probes. NEDA-3 was achieved in 86.7% of MS patients treated with DMTs. Genotype frequencies were GG 50.5%, GA 34.3%, and AA 15.2%. No differences were observed in the genetic variant AA between patients who achieved NEDA-3 versus patients who did not achieve NEDA-3 (48.7% vs. 43.1%, p = 0.6). We concluded that in Mexican patients with MS, HLA-DRB1*0403 was not associated with the therapeutic response to DMTs.


Asunto(s)
Esclerosis Múltiple , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/genética , Cadenas HLA-DRB1/genética , Predisposición Genética a la Enfermedad , Estudios de Casos y Controles , Genotipo
6.
J Prosthet Dent ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37793952

RESUMEN

STATEMENT OF PROBLEM: Research into the coverage error (CE) of gingival systems that have been expanded by using ceramic specimens created by mixing basic colors is lacking. PURPOSE: The purpose of this in vitro study was to compare the CEs of 3 ceramic gingival color systems that have been expanded with basic-color mixtures from a sample of 360 White participants and to classify the participants according to the accuracy of the shade match achieved with each system. MATERIAL AND METHODS: L*a*b* color coordinates were recorded in 3 zones of attached gingiva for 360 White participants with healthy gingival tissue (187 men and 173 women). The CEs were calculated for 3 ceramic gingival systems that had been expanded with specimens obtained by mixing the basic colors in consecutive order, the color percentages in each mixture having been altered by 10% increments. The systems were Heraceram (Kulzer GmbH) (n=51); Vita VM9 (Vita-Zahnfabrik) (n=41); and IPS Style (Ivoclar AG) (n=41). The participants were classified into 3 groups according to how well the selected shade matched their gingival color (excellent, acceptable, or poor). The data were analyzed using a 1-way ANOVA with a randomized block design and the homogeneity of proportions test (α=.05). RESULTS: Statistically significant differences were found between the CEs of the 3 expanded gingival systems in the 3 zones where gingival color was measured (P<.001). The expanded Heraceram system had the smallest CE (ΔE00: minimum 2.66 in the middle zone and maximum 2.95 at the mucogingival line). In the 3 gingival zones, the expanded IPS Style system produced the largest percentage of participants with a poor shade match (ΔE00: minimum 71.4% at the mucogingival line and maximum 75.8% at the free gingival margin), while the expanded Heraceram system had the lowest percentage of participants with a poor shade match (ΔE00: minimum 33.3% in the middle zone and maximum 41.7% at the mucogingival line). CONCLUSIONS: The CEs calculated for the expanded Vita VM9 and IPS Style ceramic gingival color systems exceeded the clinical acceptability thresholds in the 3 zones examined. According to the ΔE00 formula, the gingival color of at least 33% of participants matched poorly with the expanded systems studied.

7.
Horm Behav ; 146: 105279, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36370679

RESUMEN

Androgen receptors (AR) are crucial in the control of male sexual behavior and sex preference. AR are particularly concentrated in areas related with the neuroendocrine control of sex preference including the medial amygdala (MeA), the ventromedial nucleus of the hypothalamus (VMH), the bed nucleus of the stria terminalis (BNST), the medial preoptic area (MPOA), the nucleus accumbens (Acb), the suprachiasmatic (SCh) and supraoptic (SO) nuclei, but also seem to be important for the control of reproductive processes in the hippocampus (CA1-CA4 and dentate gyrus, DG). In the present study we analyzed the density of AR in these brain areas of adult male rats with sexual preference (established in a three-compartment box). Same-sex preference was produced in male rats by the prenatal administration of the aromatase inhibitor, letrozole (0.56 µg/kg/ml s.c. G10-22) that usually produces 1-2 animals per litter with same sex preference, while the others retain a female sex preference. We also included a group of proestrus females that had a clear preference for a sexually active male. AR were analyzed by immunocytochemistry using PG21 as primary antibody. We also measured total plasma testosterone concentrations by radioimmunoassay. In males with same sex preference there was a specific AR overexpression in CA3 and CA4 that suggests a feminized pattern because females in proestrus trend to show a higher density of AR in these hippocampal areas. Sex differences in AR density were found in the anterior cingulate cortex (ACg) and frontoparietal cortex (FrPa). Serum levels of testosterone did not differ between groups. Data are discussed based on the role of AR in the hippocampus.


Asunto(s)
Receptores Androgénicos , Núcleos Septales , Animales , Femenino , Masculino , Ratas , Receptores Androgénicos/metabolismo , Núcleos Septales/metabolismo , Encéfalo/metabolismo , Testosterona , Conducta Sexual
8.
Nutr Neurosci ; 25(3): 519-529, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32420816

RESUMEN

INTRODUCTION: Parkinson's disease (PD) is a chronic neurological disorder whose pathogenesis involves the loss of dopaminergic neurons and dopamine terminals, formation of Lewy bodies, and microgliosis. Its treatment includes dopamine-based drugs with limited results and adverse effects. Additionally, some neuroleptic drugs used for mental disorders produce side effects referred to as parkinsonism. Dietary interventions with ω-3 polyunsaturated fatty acids (ω-3 PUFA) have attracted attention since they play a key role in most of the processes associated with PD etiology. OBJECTIVE: The purpose of our work was to investigate the effects of an ω-3 PUFA rich algal oil on locomotive alterations induced by haloperidol and D2 receptor protein and gene expression in Wistar rats. METHODOLOGY: Pre- and co-supplementation of algal oil (300 mg of ω-3 FA/kg/day for six weeks) and haloperidol (1.5 mg/kg/day for two weeks) were evaluated. RESULTS: Haloperidol provoked locomotive alterations in the Open Field Test and a 43% diminution in D2 receptor in brain membranes; in pre-supplemented rats a 93% increase in D2 receptor protein expression and a partial maintenance of locomotory performance were observed, while in co-supplemented rats D2 receptor protein expression was maintained as in control rats, although locomotive behavior was found diminished as in haloperidol rats. CONCLUSIONS: These results confirm the beneficial effects of ω-3 PUFA over locomotory alterations and as neuroprotective and neurorestorative compounds and demonstrates a stimulatory action on D2 receptor presence, as a mechanism by which these fatty acids participate in brain health.


Asunto(s)
Ácidos Grasos Omega-3 , Trastornos Parkinsonianos , Animales , Dopamina/metabolismo , Ácidos Grasos Omega-3/farmacología , Haloperidol , Humanos , Ratas , Ratas Wistar
9.
Curr Microbiol ; 79(3): 72, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35067729

RESUMEN

The role played by Blastocystis in humans has been a subject of discussion due to its intestinal effects and modifications in the intestinal microbiota. We aimed to analyze the relationship between Blastocystis subtypes ST1-4 and 7, the Firmicutes to Bacteroidetes ratio (F/B ratio) of fecal microbiota, and chronic stress in university students. This study had a cross-sectional design with a sample of 202 students. We analyzed fecal and hair samples, and stress inventories were applied to the students. The results showed a frequency of Blastocystis-colonized students of 52.97%. Regarding fecal microbiota, a median RAU of 0.801 for Firmicutes and 0.82 of Bacteroidetes were obtained, with an F/B ratio of 0.83. A low F/B ratio (66.04%) was more frequent in Blastocystis-colonized students, whereas a high F/B ratio (68.09%) (p = < 0.0001) was found in the Blastocystis-non-colonized. Only Blastocystis ST3 did not significantly correlate with a low F/B ratio (p = 0.290). The ST4 was associated with lower values of cortisol (p = 0.030), psychological stress (p = 0.040), and lower frequency of constipation (p = 0.010). Only two students with the ST1 had abdominal pain (p = 0.007). Our results suggest that colonization by Blastocystis subtypes can modify the intestinal microbiota due to a decreased ratio between the two most representative phyla (F/B). Also, the results of this study show that ST4 colonization is related to a lower level of chronic stress.


Asunto(s)
Infecciones por Blastocystis , Blastocystis , Bacteroidetes , Infecciones por Blastocystis/epidemiología , Estudios Transversales , Heces , Firmicutes , Humanos , Estudiantes , Universidades
10.
BMC Microbiol ; 21(1): 339, 2021 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-34895145

RESUMEN

BACKGROUND: Blastocystis is a typical anaerobic colon protist in humans with controversial pathogenicity and has relation with alterations in the intestinal microbiota composition (dysbiosis), whose eventual indicator is the Firmicutes/Bacteroidetes ratio (F/B ratio); this indicator is also linked to complications such as diabetes, obesity, or inflammatory bowel disease. The present study investigated the prevalence of Blastocystis and its association with Firmicutes/Bacteroidetes ratio in healthy and metabolic diseased subjects. METHODS: Fecal and blood samples were collected consecutively from 200 healthy subjects and 84 subjects with metabolic disease; Blastocystis and its most frequent subtypes were identified by end-point PCR and the two most representative phyla of the intestinal microbiota Firmicutes and Bacteroidetes by real-time PCR. RESULTS: The prevalence of Blastocystis in healthy subjects was 47.0, and 65.48% in subjects with metabolic disease; the most prevalent subtype in the total population was ST3 (28.38%), followed by ST1 (14.86%), ST4, ST5, and ST7 (each one of them with 14.19% respectively), and finally ST2 (8.78%). The low F/B ratio was associated with the prevalence of Blastocystis in the two cohorts FACSA (OR = 3.78 p < 0.05) and UNEME (OR = 4.29 p < 0.05). Regarding the subtype level, an association between the FACSA cohort ST1 and ST7 with low Firmicutes/Bacteroidetes ratio was found (OR = 3.99 and 5.44 p < 0.05, respectively). CONCLUSIONS: The evident predatory role of Blastocystis over Firmicutes phylum was observed in both cohorts since the abundance of bacterial group's Bacteroidetes increases in the groups colonized by this eukaryote and, therefore, may have a beneficial effect.


Asunto(s)
Bacteroidetes/aislamiento & purificación , Blastocystis/aislamiento & purificación , Firmicutes/aislamiento & purificación , Enfermedades Metabólicas/microbiología , Enfermedades Metabólicas/parasitología , Blastocystis/clasificación , Blastocystis/genética , Estudios de Cohortes , Heces/microbiología , Heces/parasitología , Femenino , Microbioma Gastrointestinal , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Adulto Joven
11.
Prostaglandins Other Lipid Mediat ; 153: 106519, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33238201

RESUMEN

Extracellular vesicles (EVs) are vesicles secreted by normal and malignant cells that are implicated in tumor progression. Linoleic acid (LA) is an essential polyunsaturated fatty acid that induces migration, invasion and an increase in phospholipase D activity in breast cancer cells. In this study, we determined whether stimulation of MDA-MB-231 breast cancer cells with LA induces the secretion of EVs, which can mediate cell processes related with angiogenesis in human umbilical vein endothelial cells (HUVECs). Our findings demonstrate that treatment of MDA-MB-231 cells with 90 µM LA for 48 h induce an increase in the number of EVs released. Moreover, EVs from MDA-MB-231 stimulated with 90 µM LA induce FAK and Src activation and migration via FAK and Src activity, whereas the secretion of these EVs is through FFAR1 and FFAR4 activation in HUVECs. The EVs from MDA-MB-231 cells treated with LA also increase proliferation, invasion, MMP-9 secretion, an increase of MMP-2 secretion and formation of new tubules in HUVECs. In summary, we demonstrate, for the first time, that treatment with LA induces the release of EVs from MDA-MB-231 cells that induce cellular processes involved with angiogenesis in HUVECs.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana , Neoplasias de la Mama , Humanos , Ácido Linoleico , Metaloproteinasa 2 de la Matriz
12.
Compr Rev Food Sci Food Saf ; 19(6): 3323-3342, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33337060

RESUMEN

Peru has a commodities-based economy where agriculture plays an essential role in the nation's development. Among agricultural products, fruits and vegetables are foundational to Peruvian culture and a healthy and nutritious diet. Produce is also the primary income source for thousands of small-scale farmers and producers throughout the country. Peru has significant potential to export agricultural and value-added products. Nevertheless, the Peruvian food chain has weak food safety and quality standards, limiting access to international markets. The inherent lack of food safety surveillance and management systems negatively affects public health. In the past decade, fresh and raw produce has been associated with several foodborne outbreaks worldwide, resulting in significant health and economic losses. This alarming situation for public health officials and regulators has called for the strengthening of produce safety standards and food safety risk management for safer food and to reduce the incidence of foodborne illnesses. This review summarizes the current status of produce safety in Peru and explores opportunities (e.g., policy, university capacity development) toward a safer food system.


Asunto(s)
Microbiología de Alimentos , Inocuidad de los Alimentos/métodos , Agricultura/métodos , Contaminación de Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Humanos , Perú , Salud Pública/legislación & jurisprudencia , Salud Pública/normas
13.
Horm Behav ; 109: 56-63, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30769015

RESUMEN

Repeated testing for masculine sexual behavior influences female sex preference in males. Males perinatally treated with aromatase inhibitors show male preference, but also copulate with the receptive female. Such copulation modifies sex preference most likely because of its rewarding properties. In this study, we intended to equal the incentive value of both stimuli -in the sex preference test- by using receptive females with vaginal occlusion. Vehicle and letrozole-treated (0.56 µg/kg, gestation days 10-21) males were repeatedly tested for sex preference at 40, 55, 70, 85 and 100 days of age. These ages were selected because males of 40 days are unable to copulate, while by 100 days of age almost all males show the complete repertoire of masculine sexual behavior. At 40 days of age, males of all groups fail to show sex preference and none of them was able to copulate. In controls of 100 days of age all males showed female-sex preference and all intromitted the female. A large proportion (44%) of vehicle-treated males that could not copulate the female showed male preference. Twenty to 30% of the prenatally letrozole treated males also had same-sex preference even if they could copulate; and most of them (67%) had a male preference when copulation was precluded. These data support the idea that copulation is crucial for developing a female preference in control animals. The results suggest that brain changes produced by estrogens along early development and stimuli coming from the partner are essential for shaping sex preference.


Asunto(s)
Conducta de Elección/efectos de los fármacos , Letrozol/farmacología , Conducta Sexual Animal/efectos de los fármacos , Parejas Sexuales , Animales , Inhibidores de la Aromatasa/farmacología , Copulación/efectos de los fármacos , Copulación/fisiología , Femenino , Masculino , Motivación/efectos de los fármacos , Motivación/fisiología , Embarazo , Ratas , Ratas Wistar , Factores Sexuales , Parejas Sexuales/psicología
14.
Sensors (Basel) ; 19(20)2019 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-31652607

RESUMEN

Exploration of unknown environments is a fundamental problem in autonomous robotics that deals with the complexity of autonomously traversing an unknown area while acquiring the most important information of the environment. In this work, a mobile robot exploration algorithm for indoor environments is proposed. It combines frontier-based concepts with behavior-based strategies in order to build a topological representation of the environment. Frontier-based approaches assume that, to gain the most information of an environment, the robot has to move to the regions on the boundary between open space and unexplored space. The novelty of this work is in the semantic frontier classification and frontier selection according to a cost-utility function. In addition, a probabilistic loop closure algorithm is proposed to solve cyclic situations. The system outputs a topological map of the free areas of the environment for further navigation. Finally, simulated and real-world experiments have been carried out, their results and the comparison to other state-of-the-art algorithms show the feasibility of the exploration algorithm proposed and the improvement that it offers with regards to execution time and travelled distance.

15.
J Fish Biol ; 93(2): 370-381, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30069905

RESUMEN

The anchoveta (Engraulis ringens) plays a key role in the ecology of the Humboldt Current System and is of major economic importance; however, many aspects of its early life history are still poorly understood. In this study, an analysis of daily age and length patterns was carried out using the sagittal otoliths from wild larvae (0-0.2 cm standard length, LS ), pre-recruits (3-6 cm total length, LT ), recruits (7-12 cm LT ) and young adults (12-15 cm LT ). Additionally, variability in growth and age at recruitment (AR ) were evaluated for recruits caught in northern Chile in 1973, 1982, 2009, 2010, 2012, 2013, 2014 and 2015. The age-length relationship showed four allometric patterns that were well described by Laird-Gompertz models. The absolute growth rates at the inflexion point (GAR ) were 0.56, 0.75, 1.22 and 1.16 mm d-1 for larvae, pre-recruits, recruits and young adults, respectively. At the interannual scale, GAR values were always >1 mm d-1 (mean ± S.D. 1.37 ± 0.21 mm d-1 ; range 1.12-1.64 mm d-1 ), irrespective of the season of hatching (i.e. winter v. spring); additionally, in most cases, GAR values were reached before the second month of life (mean ± S.D. 50.47 ± 9.73 days) at c. 4 cm LT (mean ± S.D. 4.22 ± 0.29 cm). Mean AR was < 150 days (112 ± 29 days; range 75-149 days); in contrast, estimates of AR were higher and growth rates were lower in 1973, 1983 and 2000. These results demonstrate very fast growth and early AR of anchoveta in northern Chile, suggesting most fish are removed by the fisheries at very early ages. An evaluation of the implications of these results on stock assessment and management of this species is highly recommended.


Asunto(s)
Peces/crecimiento & desarrollo , Animales , Biometría , Chile , Explotaciones Pesqueras , Peces/anatomía & histología , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Membrana Otolítica/anatomía & histología , Estaciones del Año
16.
Molecules ; 23(8)2018 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-30060472

RESUMEN

Pine sawdust and wheat straw are abundant lignocellulosic wastes that have been recently converted into bioethanol under a biochemical platform scheme whose main waste is lignin. Lignin can be transformed into a wide variety of high added-value products, including its functionalization as a catalyst. A key step in the synthesis of a lignin-based catalyst is the sulfonation reaction, whose operating conditions, namely, H2SO4 to lignin ratio (mL/g), temperature and time, have been arbitrarily chosen. In this contribution, an optimization methodology (i.e., Box-Behnken) is applied in order to found the operating conditions during the sulfonation reaction that maximizes the total acid sites density of lignin-based catalysts from pine sawdust and wheat straw. The optimization results show that the time in sulfonation reactions can be significantly reduced, compared to those previously reported, without affecting the performance of both catalysts in esterification reactions. These results could be further considered for energy and costs reduction purposes during the conceptual design engineering of the sulfonation reaction.


Asunto(s)
Lignina/química , Pinus/química , Ácidos Sulfúricos/química , Triticum/química , Catálisis , Polvo/análisis , Temperatura , Tiempo
17.
BMC Cardiovasc Disord ; 17(1): 100, 2017 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-28410571

RESUMEN

BACKGROUND: The inflammatory process in aortic valvular stenosis persists after surgery to replace the valve in almost half of the patients. No association has been found to its persistence. The main objective of this study was to evaluate the inflammatory response in patients with aortic stenosis through the determination of several biomarkers in plasma measured before and after the valvular replacement and to seek an association with the type of prosthesis used. METHODS: This is an observational study with a follow up of 6 months in subjects with severe aortic stenosis. Seric concentrations of TNFa, IL-1, IL-6 and ICAM and echocardiographic variables were quantified previous to the surgery and a week and 6 months after it. A group of control subjects paired by age and gender was included. RESULTS: Seventy-nine subjects were studied of which 57% were male; the average age was of 59 (± 11.4) years. Previous to surgery, the concentration of cytokines was higher in patients than in control subjects. A biological prosthesis was implanted in 48 patients and a mechanical prosthesis in 31. Both, types of prosthesis have components made of titanium. The echocardiograms 1 week and 6 months after the surgery showed a decrease in the mean aortic gradient and an increase in the valvular area (p = 0.001). Half of the patients still showed high proinflammatory cytokine levels. There were no differences according to the type of prosthesis implanted after adjustments for demographic variables, comorbidities and echocardiographic data. CONCLUSIONS: The inflammatory response caused by both types of valvular prothesis at 6 months after implantation were similar. Both types of prosthesis are recommended, they had similarities in hemodynamic profiles registered with Doppler echocardiography. Age of the patient or the suitability use of anticoagulants determines the type of prosthesis to be used.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Biomarcadores/sangre , Bioprótesis , Prótesis Valvulares Cardíacas , Inflamación/sangre , Estenosis de la Válvula Aórtica/sangre , Ecocardiografía Doppler , Femenino , Estudios de Seguimiento , Humanos , Inflamación/etiología , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Periodo Preoperatorio , Estudios Prospectivos , Diseño de Prótesis , Factores de Tiempo
18.
J Heart Valve Dis ; 26(3): 334-343, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-29092120

RESUMEN

BACKGROUND AND AIM OF THE STUDY: The aim of this retrospective study was to evaluate the inflammatory response in patients with aortic and/or mitral prostheses, and to correlate the level of inflammatory markers with prosthesis functionality. METHODS: A total of 48 patients with biological or mechanical prostheses was included in the study, in which levels of tumor necrosis factor-alpha (TNFα), interleukin (IL)-1, -4, and -6, interferon-gamma (IFNγ), osteopontin (OPN), intercellular adhesion molecule (ICAM), vascular cell adhesion molecule (VCAM), endothelin-1 and C-reactive protein were analyzed. Functionality of the prosthesis was evaluated using transthoracic echocardiography at three years after surgery. RESULTS: The mean period from the date of surgery was seven years. High levels of IL-1 were found in patients with mechanical prostheses compared to those with bioprostheses (p = 0.04). Patients with aortic bioprostheses and stenosis had higher levels of OPN and endothelin-1, those with aortic mechanical prostheses with stenosis had increased levels of matrix metalloproteinase (MMP)-9, OPN and ICAM, and those with aortic mechanical leakage had increased levels of MMP-1 and endothelin-1. In mitral bioprostheses with leakage of endothelin-1, ICAM and MMP-9 levels were increased, while in mechanical prostheses with leakage there were increases of ICAM and endothelin-1. Tricuspid bioprostheses with double lesions had increased levels of OPN and endothelin-1. CONCLUSIONS: Valvular dysfunction was similar across the types of prosthesis material. IL-1 was increased in subjects with mechanical prostheses independently of dysfunction, while in biological prostheses there were increases in OPN and endothelin-1, and these were related to valvular dysfunction. Given that in the analysis of durability and functionality there were no significant differences between biological and mechanical prostheses, biological prostheses may represent the first treatment option in patients with low economic resources, the elderly, and even young patients.


Asunto(s)
Válvula Aórtica/cirugía , Bioprótesis , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Prótesis Valvulares Cardíacas , Mediadores de Inflamación/inmunología , Inflamación/inmunología , Válvula Mitral/cirugía , Pericardio/trasplante , Anciano , Anciano de 80 o más Años , Animales , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/inmunología , Válvula Aórtica/fisiopatología , Bovinos , Ecocardiografía Transesofágica , Femenino , Xenoinjertos , Humanos , Inflamación/sangre , Inflamación/diagnóstico , Mediadores de Inflamación/sangre , Masculino , Persona de Mediana Edad , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/inmunología , Válvula Mitral/fisiopatología , Pericardio/diagnóstico por imagen , Pericardio/inmunología , Diseño de Prótesis , Falla de Prótesis , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
19.
Nanomedicine ; 13(8): 2587-2596, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28756091

RESUMEN

Silver nanoparticles (AgNPs) are promising antibacterial nanomaterials for diagnostic and treatment of diabetes. However, toxicity and adverse cardiac responses induced by AgNPs related to nitric oxide (NO) and oxidative stress (OS) are described. Moreover, little is known about the diabetes influence upon AgNPs-toxicity. The aim of this work was to evaluate cardiovascular function in response to AgNPs through measuring perfusion pressure (PP) and left ventricle pressure (LVP), using perfused hearts from streptozotocin (STZ)-induced diabetic rats and identify the role of NO and OS. High concentrations but not the lower concentrations of AgNPs, promotes increases in PP and LVP, as well as increased OS. Additionally, diabetes alters the classic effects of phenylephrine (Phe) and acetylcholine (ACh). These data suggest that diabetes may intensify AgNPs-cardiotoxicity. Nevertheless, the precise mechanism of action is still under elucidation.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Corazón/efectos de los fármacos , Corazón/fisiopatología , Nanopartículas del Metal/toxicidad , Estrés Oxidativo/efectos de los fármacos , Plata/toxicidad , Acetilcolina/metabolismo , Animales , Diabetes Mellitus Experimental/metabolismo , Masculino , Miocardio/metabolismo , Óxido Nítrico/metabolismo , Ratas Wistar
20.
Sensors (Basel) ; 17(2)2017 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-28146049

RESUMEN

In this work, a system is developed for semantic labeling of locations based on what people do. This system is useful for semantic navigation of mobile robots. The system differentiates environments according to what people do in them. Background sound, number of people in a room and amount of movement of those people are items to be considered when trying to tell if people are doing different actions. These data are sampled, and it is assumed that people behave differently and perform different actions. A support vector machine is trained with the obtained samples, and therefore, it allows one to identify the room. Finally, the results are discussed and support the hypothesis that the proposed system can help to semantically label a room.

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