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1.
Am J Primatol ; 86(3): e23501, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37170705

RESUMEN

The majority of the 11 species of owl monkeys (Aotus spp.) have declining populations or are listed as data deficient. Deforestation due to agriculture, development, or logging poses threats to owl monkeys throughout their range. In some areas, Aotus are hunted for bushmeat or trapped for the wildlife trade. In Colombia, the country with the greatest number of Aotus species, owl monkeys are also threatened by civil unrest. To help combat these challenges, nonprofit organizations and field researchers in habitat countries have successfully implemented a variety of conservation projects such as censusing and monitoring owl monkey populations, establishing protected areas, reforesting degraded areas, filing lawsuits to protect wild populations, helping law enforcement with environmental regulation, and promoting environmental education. We highlight some of the conservation successes and suggest actions people around the world can take to contribute to these important efforts.


Asunto(s)
Aotidae , Animales , Aotidae/fisiología
2.
Risk Anal ; 41(12): 2356-2391, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34056745

RESUMEN

Risk-informed asset management is key to maintaining optimal performance and efficiency of urban sewer systems. Although sewer system failures are spatiotemporal in nature, previous studies analyzed failure risk from a unidimensional aspect (either spatial or temporal), not accounting for bidimensional spatiotemporal complexities. This is owing to the insufficiency of good-quality data, which ultimately leads to under-/overestimation of failure risk. Here, we propose a generalized methodology/framework to facilitate a robust spatiotemporal analysis of urban sewer system failure risk, overcoming the intrinsic challenges of data imperfections-e.g., missing data, outliers, and imbalanced information. The framework includes a two-stage data-driven modeling technique that efficiently models the highly right-skewed sewer system failure data to predict the failure risk, leveraging a bidimensional space-time approach. We implemented our analysis for Bogotá, the capital city of Colombia. We train, test, and validate a battery of machine learning algorithms-logistic regression, decision trees, random forests, and XGBoost-and select the best model in terms of goodness-of-fit and predictive accuracy. Finally, we illustrate the applicability of the framework in planning/scheduling sewer system maintenance operations using state-of-the-art optimization techniques. Our proposed framework can help stakeholders to analyze the failure-risk models' performance under different discrimination thresholds, and provide managerial insights on the model's adequate spatial resolution and appropriateness of decentralized management for sewer system maintenance.

3.
Opt Express ; 28(5): 6609-6617, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32225905

RESUMEN

Ultra-High Concentrator Photovoltaic (UHCPV) designs with up to more than 6000× geometrical concentration and optical efficiency of 80% are demonstrated in this paper by means of ray tracing simulations. These are developed based on Cassegrain-Koehler concentrators [Opt. Lett.41(9), 1985 (2016)], with four pairs of paraboloid-hyperboloid mirrors and a central receiver composed of four Cartesian ovals of revolution. Designs at different geometrical concentrations are analyzed based on their aspect ratios (F-number). The most compact designs exhibit highest optical efficiencies. Moreover, a 3015× geometrical concentration one-cell prototype, made of aluminum and PMMA (poly(methyl methacrylate)), is fabricated and characterized indoors, achieving an effective concentration of 938 suns. This represents the CPV module with the highest geometrical concentration that has been experimentally investigated that could be found in the scientific literature.

4.
Horm Behav ; 90: 56-63, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28232065

RESUMEN

In biparental mammals, the factors facilitating the onset of male parental behavior are not well understood. While hormonal changes in fathers may play a role, prior experience with pups has also been implicated. We evaluated effects of prior exposure to pups on paternal responsiveness in the biparental California mouse (Peromyscus californicus). We analyzed behavioral, neural, and corticosterone responses to pups in adult virgin males that were interacting with a pup for the first time, adult virgin males that had been exposed to pups 3 times for 20min each in the previous week, and new fathers. Control groups of virgins were similarly tested with a novel object (marble). Previous exposure to pups decreased virgins' latency to approach pups and initiate paternal care, and increased time spent in paternal care. Responses to pups did not differ between virgins with repeated exposure to pups and new fathers. In contrast, repeated exposure to a marble had no effects. Neither basal corticosterone levels nor corticosterone levels following acute pup or marble exposure differed among groups. Finally, Fos expression in the medial preoptic area, ventral and dorsal bed nucleus of the stria terminalis was higher following exposure to a pup than to a marble. Fos expression was not, however, affected by previous exposure to these stimuli. These results suggest that previous experience with pups can facilitate the onset of parental behavior in male California mice, similar to findings in female rodents, and that this effect is not associated with a general reduction in neophobia.


Asunto(s)
Sensibilización del Sistema Nervioso Central/fisiología , Corticosterona/metabolismo , Padre/psicología , Comportamiento de Nidificación/fisiología , Conducta Paterna/fisiología , Peromyscus , Corteza Suprarrenal/metabolismo , Animales , Animales Recién Nacidos , Conducta Animal/fisiología , Femenino , Masculino , Peromyscus/metabolismo , Peromyscus/fisiología , Peromyscus/psicología , Área Preóptica/fisiología , Conducta Social
5.
J Immunol ; 194(7): 3327-39, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25725101

RESUMEN

Studies on the heterogeneity and plasticity of macrophage populations led to the identification of two major polarization states: classically activated macrophages or M1, induced by IFN-γ plus LPS, and alternatively activated macrophages, induced by IL-4. We studied the expression of multiple phospholipase A2 enzymes in human macrophages and the effect that polarization of the cells has on their levels. At least 11 phospholipase A2 genes were found at significant levels in human macrophages, as detected by quantitative PCR. None of these exhibited marked changes after treating the cells with IFN-γ plus LPS. However, macrophage treatment with IL-4 led to strong upregulation of the secreted group V phospholipase A2 (sPLA2-V), both at the mRNA and protein levels. In parallel with increasing sPLA2-V expression levels, IL-4-treated macrophages exhibited increased phagocytosis of yeast-derived zymosan and bacteria, and we show that both events are causally related, because cells deficient in sPLA2-V exhibited decreased phagocytosis, and cells overexpressing the enzyme manifested higher rates of phagocytosis. Mass spectrometry analyses of lipid changes in the IL-4-treated macrophages suggest that ethanolamine lysophospholipid (LPE) is an sPLA2-V-derived product that may be involved in regulating phagocytosis. Cellular levels of LPE are selectively maintained by sPLA2-V. By supplementing sPLA2-V-deficient cells with LPE, phagocytosis of zymosan or bacteria was fully restored in IL-4-treated cells. Collectively, our results show that sPLA2-V is required for efficient phagocytosis by IL-4-treated human macrophages and provide evidence that sPLA2-V-derived LPE is involved in the process.


Asunto(s)
Fosfolipasas A2 Grupo V/genética , Interleucina-4/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Fagocitosis/genética , Fagocitosis/inmunología , Fosfatidiletanolaminas/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Fosfolipasas A2 Grupo V/deficiencia , Fosfolipasas A2 Grupo V/metabolismo , Voluntarios Sanos , Humanos , Hidrólisis , Interleucina-4/farmacología , Isoenzimas , Metabolismo de los Lípidos , Macrófagos/efectos de los fármacos , Masculino , Fagocitosis/efectos de los fármacos , Fosfatidiletanolaminas/farmacología
6.
J Oral Pathol Med ; 46(7): 549-557, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27759906

RESUMEN

BACKGROUND: Periodontal disease is chronic inflammatory process that affects the attachment structures of the teeth and constitutes a significant cause of tooth loss in adults. Although different bacteria play an important role in the triggering of this condition, the progression and severity of the disease are strongly affected by the host immune response, which is under the control of different immune regulatory mechanisms, including T regulatory (Treg) cells. The aim of this study was to assess the frequency and function of CD69+ Treg lymphocytes in patients with chronic periodontal disease. METHODS: Peripheral blood samples (n = 33) and gingival tissue (n = 9) were obtained from patients with chronic periodontal disease. Blood samples from 25 healthy individuals were also studied. Levels of CD69+ Treg lymphocytes in peripheral blood and gingival tissue were determined by six-color multiparametric flow cytometry, immunofluorescence, and immunohistochemistry. The immune regulatory function of CD69+ Treg cells was tested by an in vitro assay of inhibition of lymphocyte activation. RESULTS: Percentages of CD69+ Treg cells were significantly higher in the peripheral blood from patients with active periodontal disease compared to healthy controls, and these percentages inversely correlated with the periodontal attachment loss. Increased numbers of these Treg cells were detected in the gingival tissue from active PD patients compared to their peripheral blood. However, the suppressive function of CD69+ Treg cells was significantly diminished in patients with periodontal disease compared to healthy controls. CONCLUSIONS: Our data suggest that CD69+ Treg cells seem to be another important piece in the complex immunopathogenesis of periodontal disease.


Asunto(s)
Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/inmunología , Lectinas Tipo C/inmunología , Enfermedades Periodontales/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Encía/inmunología , Humanos , Activación de Linfocitos , Masculino , Persona de Mediana Edad
7.
Opt Lett ; 41(9): 1985-8, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27128055

RESUMEN

Ultra-high concentrator photovoltaics (UHCPV), with concentrations higher than 1000 suns, have been pointed out by different authors as having great potential for being a cost-effective PV technology. This Letter presents a UHCPV Cassegrain-based optical design in which the sunrays are concentrated and sent from four different and independent paraboloid-hyperboloid pairs optical units onto a single central receiver. The optical design proposed has the main advantage of the achievement of ultra-high concentration ratios using relative small mirrors with similar performance values of efficiency, acceptance angle, and irradiance uniformity to other designs.

8.
Biochim Biophys Acta ; 1841(12): 1661-71, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25450448

RESUMEN

The classical regard of lipid droplets as mere static energy-storage organelles has evolved dramatically. Nowadays these organelles are known to participate in key processes of cell homeostasis, and their abnormal regulation is linked to several disorders including metabolic diseases (diabetes, obesity, atherosclerosis or hepatic steatosis), inflammatory responses in leukocytes, cancer development and neurodegenerative diseases. Hence, the importance of unraveling the cell mechanisms controlling lipid droplet biosynthesis, homeostasis and degradation seems evident Phospholipase A2s, a family of enzymes whose common feature is to hydrolyze the fatty acid present at the sn-2 position of phospholipids, play pivotal roles in cell signaling and inflammation. These enzymes have recently emerged as key regulators of lipid droplet homeostasis, regulating their formation at different levels. This review summarizes recent results on the roles that various phospholipase A2 forms play in the regulation of lipid droplet biogenesis under different conditions. These roles expand the already wide range of functions that these enzymes play in cell physiology and pathophysiology.


Asunto(s)
Gotas Lipídicas/metabolismo , Fosfolipasas A2/metabolismo , Animales , Calcio/metabolismo , Humanos , Modelos Biológicos
9.
J Zool (1987) ; 296(1): 23-29, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-26005292

RESUMEN

Studies of biparental mammals demonstrate that males may undergo systematic changes in body mass as a consequence of changes in reproductive status; however, these studies typically have not teased apart effects of specific social and reproductive factors, such as cohabitation with a female per se, cohabitation with a breeding female specifically, and engagement in paternal care. We aimed to determine whether California mouse (Peromyscus californicus) fathers undergo systematic changes in body mass and if so, which specific social/reproductive factor(s) might contribute to these changes. We compared mean weekly body masses over a 5-week period in 1) males housed with another male vs. males housed with a non-reproductive (tubally ligated) female; 2) males housed with a tubally ligated female vs. males housed with a female that was undergoing her first pregnancy; and 3) experienced fathers housed with vs. without pups during their mate's subsequent pregnancy. Body mass did not differ between males housed with another male and those housed with a non-reproductive female; however, males housed with a non-reproductive female were significantly heavier than those housed with a primiparous female. Among experienced fathers, those housed with pups from their previous litter underwent significant increases in body mass across their mates' pregnancy, whereas fathers housed without pups did not. These results suggest that male body mass is reduced by cohabitation with a breeding (pregnant) female, but not by cohabitation with a non-reproductive female, and that increases in body mass across the mate's pregnancy are associated with concurrent care of offspring rather than cohabitation with a pregnant female. Additional work is needed to determine the mechanisms and functional significance, if any, of these changes in male body mass with reproductive condition.

10.
Dev Psychobiol ; 56(4): 812-20, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24114333

RESUMEN

Parturient females ingest placenta in most mammalian species, whereas fathers may do so in species in which both parents provide care for their offspring. To determine if the propensity to eat placenta varies with reproductive status in the biparental California mouse, we presented placenta to virgin (housed with a same-sex pairmate), expectant (pregnant with their first litter), and multiparous adult males and females. Liver was presented identically, 3-7 days later, as a control. Multiparous females were more likely to eat placenta than expectant and virgin females (p-values <0.016), whereas both multiparous and expectant males had higher incidences of placentophagia than virgins (p-values <0.016). Liver consumption did not differ among groups within either sex. These results suggest that propensity to eat placenta increases with maternal/birthing experience in females, and with paternal experience and/or cohabitation with a pregnant female in males.


Asunto(s)
Conducta Animal/fisiología , Conducta Alimentaria/fisiología , Peromyscus/fisiología , Placenta , Reproducción/fisiología , Animales , Femenino , Masculino , Conducta Paterna/fisiología , Embarazo
11.
Medicina (B Aires) ; 84(2): 206-220, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38683505

RESUMEN

INTRODUCTION: Chia and flax seeds are rich in alphalinolenic acid (ALA), which is bioconverted into the active derivatives eicosapentaenoic (EPA) and docosahexaenoic (DHA) having multiple beneficial effects. However, there is limited knowledge about the antiinflammatory effects of chia and flax integral flours diets rich in ALA. OBJECTIVE: The study aimed to evaluate the antiinflammatory effect of dietary supplementation with integral chia and flax flours in a murine model of LPSinduced systemic inflammation. METHODS: Balb/c mice were distributed into three groups: diet A (control), diet B (supplemented with integral chia flour), and diet C (supplemented with integral flax flour). Nutritional, hematological, and biochemical determinations were performed. ALA, EPA, and DHA were assessed by GC-MS in the liver, brain, cardiac and skeletal muscles. NF-kB immunoassays were performed in kidney, liver, and peritoneal macrophages, respectively. The phagocytic capacity was determined in peritoneal macrophages and the expression of the pro- and anti-inflammatory cytokines was assessed by RT-qPCR in the kidney, liver, and spleen. RESULTS: Diets B and C exhibited optimal nutritional adequacy and caused increased levels of ALA, EPA, and DHA in critical tissues compared to the control. The phagocytic capacity of murine peritoneal macrophages (p< 0.01) and IL-10 transcription increased, whereas the expression of NF-κB, IL-1Β, IL-6, and TNF-α decreased in animals fed both experimental diets. CONCLUSIONS: This work contributes to the current knowledge of the anti-inflammatory effects of chia and flax integral flours rich in ALA and reinforces the health advantages of their consumption.


Introducción: Las semillas de chía y lino son ricas en ácido alfa-linolénico (ALA), sus derivados activos eicosapentaenoico (EPA) y docosahexaenoico (DHA) ejercen probados efectos beneficiosos. Existe un conocimiento limitado sobre los efectos protectores de ambas semillas bajo la forma de harinas integrales, siendo de particular interés el efecto antiinflamatorio. OBJETIVO: El objetivo de este trabajo fue evaluar el efecto antiinflamatorio de la suplementación dietaria con harinas integrales de semillas de chía y lino en un modelo murino de inflamación sistémica inducido por LPS. Métodos: Ratones de la cepa Balb/c fueron distribuidos en tres grupos: dieta A (control), dieta B (suplementada con harina integral de chía) y dieta C (suplementada con harina integral de lino). Se efecturaron determinaciones nutricionales, hematológicas y bioquímicas. El contenido de ALA, EPA y DHA en hígado, cerebro, corazón y músculo esquelético se determinó por cromatografía GC-MS. Se realizó la inmunodetección de NF-kB en macrófagos peritoneales, riñón e hígado. Se determinó la capacidad fagocítica de macrófagos peritoneales y se evaluó la expresión de citoquinas pro y antiinflamatorias por RT-qPCR en riñón, hígado y bazo. RESULTADOS: Las dietas B y C mostraron una adecuación nutricional óptima y generaron niveles elevados de ALA, EPA y DHA en tejidos críticos. La capacidad fagocítica de los macrófagos peritoneales (p< 0.01) y la transcripción de IL-10 aumentó, mientras que la expresión de NF-κB, IL-1Β, IL-6 y TNF-α disminuyó en animales de los grupos B y C. CONCLUSIONES: Este trabajo contribuye al conocimiento actual de los efectos antiinflamatorios de ambas harinas integrales y refuerza los beneficios de su consumo.


Asunto(s)
Suplementos Dietéticos , Lino , Inflamación , Ratones Endogámicos BALB C , Animales , Inflamación/dietoterapia , Ratones , Harina/análisis , Citocinas/análisis , Modelos Animales de Enfermedad , Masculino
12.
Physiol Rep ; 11(9): e15679, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37144554

RESUMEN

Limited research exists examining how resistance training to failure affects applied outcomes and single motor unit characteristics in previously trained individuals. Herein, resistance-trained adults (24 ± 3 years old, self-reported resistance training experience was 6 ± 4 years, 11 men and 8 women) were randomly assigned to either a low-repetitions-in-reserve (RIR; i.e., training near failure, n = 10) or high-RIR (i.e., not training near failure, n = 9) group. All participants implemented progressive overload during 5 weeks where low-RIR performed squat, bench press, and deadlift twice weekly and were instructed to end each training set with 0-1 RIR. high-RIR performed identical training except for being instructed to maintain 4-6 RIR after each set. During week 6, participants performed a reduced volume-load. The following were assessed prior to and following the intervention: (i) vastus lateralis (VL) muscle cross-sectional area (mCSA) at multiple sites; (ii) squat, bench press, and deadlift one-repetition maximums (1RMs); and (iii) maximal isometric knee extensor torque and VL motor unit firing rates during an 80% maximal voluntary contraction. Although RIR was lower in the low- versus high-RIR group during the intervention (p < 0.001), total training volume did not significantly differ between groups (p = 0.222). There were main effects of time for squat, bench press, and deadlift 1RMs (all p-values < 0.05), but no significant condition × time interactions existed for these or proximal/middle/distal VL mCSA data. There were significant interactions for the slope and y-intercept of the motor unit mean firing rate versus recruitment threshold relationship. Post hoc analyses indicated low-RIR group slope values decreased and y-intercept values increased after training suggesting low-RIR training increased lower-threshold motor unit firing rates. This study provides insight into how resistance training in proximity to failure affects strength, hypertrophy, and single motor unit characteristics, and may inform those who aim to program for resistance-trained individuals.


Asunto(s)
Entrenamiento de Fuerza , Masculino , Humanos , Adulto , Femenino , Adulto Joven , Músculo Cuádriceps/fisiología , Adaptación Fisiológica , Aclimatación , Hipertrofia , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología
13.
Acta Odontol Latinoam ; 25(1): 27-32, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22928378

RESUMEN

Interaction of oral streptococci biofilm is the main etiological factor for dental caries. The aim of the study was to compare oral streptococci (OS) distribution in the biofilm of primary dentition from caries-free and caries-affected preschool Mexican children. This cross-sectional study involved 40 caries-free and 40 caries-affected children with primary dentition. Each child was examined using the dmfs index, DNA was extracted from saliva and presence of OS was determined by PCR. Data obtained showed no statistical difference regarding age and gender (P > 0.05). Streptococcus mutans (Smut), Streptococcus sobrinus (Ssob) and their combination showed significant statistical differences between groups (P < 0.05). Smut, Streptococcus sanguinis and Streptococcus gordonii had an inverse relation with dmfs index and Ssob had a direct relation similar to combined with Smut. Smut-Ssob combined with other OS showed statistical differences (P < 0.05). In free-caries group Streptococcus gordonii was more frequently identified than Smut. The ratio Smut/Streptococcus sanguinis could represent a high risk of dental caries development; this ratio was higher in the caries-affected (1.18) than in the caries-free group (0.32). In conclusion, OS play an important role in dental caries predisposition and severity, not only the presence of Smut and Srob, but also the complexity and distribution of OS in the biofilm.


Asunto(s)
Biopelículas , Caries Dental/microbiología , Boca/microbiología , Streptococcus/fisiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , México , Estudios Prospectivos , Diente Primario
14.
Heliyon ; 8(12): e12005, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36478806

RESUMEN

The purpose of this article consists of analyzing publications discussing the use of agent-based artificial intelligence models in sustainable agriculture research. The analysis involved bibliometric indicators and the Rstudio software with Bibliometrix library. The methodology is descriptive with a quantitative approach. Scientific databases SCOPUS and Web of Science were consulted and the PRISMA methodology was used during the selection process. This led to finding 86 publications that met the inclusion criteria. Amongst the results, United States was listed as the country with the highest production of scientific material, although France had a higher impact. Additionally, the bibliographical resources that help promote scientific development are open source. It was concluded that the agent-based model has been adopted to simulate different scenarios, which help decision-makers to formulate public policies in favor of sustainable agriculture. This optimizes the use of natural resources and reduces negative consequences for the environment, while also delivering value for the stakeholders of the agricultural system.

15.
Polymers (Basel) ; 14(17)2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36080707

RESUMEN

The purpose of this research is to produce and characterize bacterial cellulose (BC) films coated with chitosan (BC-CH). BC films were produced in a fermentation medium based on Camellia sinensis tea and dextrose (12 days at 25 °C) and subsequently treated with coating-forming solutions (CFSs) based on chitosan (BC-CH 0.5%, BC-CH 1.0%, and BC-CH 1.5%). As a result, the FTIR spectra of BC and BC-CH 1.5% showed the main characteristic bands of cellulose and chitosan. In the physicochemical characterization of the films, it was found that the incorporation of the chitosan coatings did not affect the thickness; however, it decreased the luminosity (L*) and increased redness (a*), yellowness (b*), and opacity (75.24%). Additionally, the light absorption properties in the UV-Vis range were improved. Furthermore, the application of the CFSs increased: the solubility (64.91%), the antimicrobial activity against S. aureus (6.55 mm) and E. coli (8.25 mm), as well as the antioxidant activity (57.71% and 24.57% free radical scavenging activity), and the content of total phenols (2.45 mg GAE/g). Finally, our results suggest that the BC-CH films developed in the present study show a potential application as active packaging material for food.

16.
Acta Trop ; 224: 106119, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34481791

RESUMEN

In South America there are three snake genera with predominantly neurotoxic venoms: Crotalus, Micrurus and Hydrophis, which include nine species/subspecies, 97 species and a single marine species, respectively. Although accidents with neurotoxic venoms are less frequent than those with anticoagulant, cytotoxic or necrotic venoms (e.g. from Bothrops), they are of major public health importance. Venoms from genus Crotalus have been extensively studied, while data on the venoms from the other two genera are very limited, especially for Hydrophis. The venoms of North and South American Crotalus species show biochemical and physiopathological differences. The former species cause bothrops-like envenomation symptoms, while the latter mainly have neurotoxic and myotoxic effects, leading to respiratory paralysis and, occasionally, renal failure by myoglobinuria and death, often with no local lesions. Micrurus and Hydrophis also cause neurotoxic envenomations. Many studies have isolated, identified and characterized new enzymes and toxins, thus expanding the knowledge of snake venom composition. The present review summarizes the currently available information on neurotoxic venoms from South American snakes, with a focus on protein composition and toxicological properties. It also includes some comments concerning potential medical applications of elapid and crotalic toxins.


Asunto(s)
Bothrops , Crotalus , Animales , Elapidae , Venenos de Serpiente/toxicidad , América del Sur
17.
Cells ; 10(2)2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669841

RESUMEN

Macrophages are professional antigen presenting cells with intense phagocytic activity, strategically distributed in tissues and cavities. These cells are capable of responding to a wide variety of innate inflammatory stimuli, many of which are signaled by lipid mediators. The distribution of arachidonic acid (AA) among glycerophospholipids and its subsequent release and conversion into eicosanoids in response to inflammatory stimuli such as zymosan, constitutes one of the most studied models. In this work, we used liquid and/or gas chromatography coupled to mass spectrometry to study the changes in the levels of membrane glycerophospholipids of mouse peritoneal macrophages and the implication of group IVA cytosolic phospholipase A2 (cPLA2α) in the process. In the experimental model used, we observed that the acute response of macrophages to zymosan stimulation involves solely the cyclooxygenase-1 (COX-1), which mediates the rapid synthesis of prostaglandins E2 and I2. Using pharmacological inhibition and antisense inhibition approaches, we established that cPLA2α is the enzyme responsible for AA mobilization. Zymosan stimulation strongly induced the hydrolysis of AA-containing choline glycerophospholipids (PC) and a unique phosphatidylinositol (PI) species, while the ethanolamine-containing glycerophospholipids remained constant or slightly increased. Double-labeling experiments with 3H- and 14C-labeled arachidonate unambiguously demonstrated that PC is the major, if not the exclusive source, of AA for prostaglandin E2 production, while both PC and PI appeared to contribute to prostaglandin I2 synthesis. Importantly, in this work we also show that the COX-1-derived prostaglandins produced during the early steps of macrophage activation restrict tumor necrosis factor-α production. Collectively, these findings suggest new approaches and targets to the selective inhibition of lipid mediator production in response to fungal infection.


Asunto(s)
Colina/metabolismo , Cromatografía Liquida/métodos , Ciclooxigenasa 1/metabolismo , Expresión Génica/genética , Glicerofosfolípidos/metabolismo , Espectrometría de Masas/métodos , Prostaglandinas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Modelos Animales de Enfermedad , Humanos , Macrófagos/metabolismo , Ratones
18.
J Cell Biochem ; 111(1): 130-7, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20506157

RESUMEN

The receptor activator of nuclear factor-kappaB ligand (RANKL) and interleukin-1beta are osteoclast activating factors which are abnormally expressed in bone marrow stromal cells and plasma cells of multiple myeloma patients. In this work we analyzed RANKL expression in human bone marrow mesenchymal stromal cells and the effect of the bisphosphonate ibandronate on RANKL expression after IL-1beta activation of ERK pathway. Mesenchymal stromal cells were obtained from bone marrow iliac aspirates from multiple myeloma patients at stages II/III and non-osteoporotics control donors; these cells were maintained under long-term culture conditions. Cells were cultured in the presence or the absence of 5 ng/ml IL-1beta and/or 5 microM ibandronate, during selected periods. mRNA for RANKL and protein levels were assayed by RT-PCR and Western blot, respectively. Human bone marrow stromal cell line HS-5 was used for assessing IL 1beta- and ibandronate-ERK phosphorylation responses. Multiple myeloma mesenchymal stromal cells differentiate from control cells by increased basal RANKL expression. IL-1beta up regulated RANKL expression showed dependent on activated MEK/ERK pathway. Finally, the bisphosphonate ibandronate, that hindered activation of the MEK/ERK pathway significantly inhibited both basal and IL-1beta dependent RANKL expression by cells. Results indicate that RANKL expression involves the MEK/ERK pathway in multiple myeloma mesenchymal stromal cells, and that early obstruction of this path, such as that achieved with ibandronate, significantly deters RANKL protein expression.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Difosfonatos/farmacología , Mieloma Múltiple/metabolismo , Ligando RANK/metabolismo , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Anciano , Conservadores de la Densidad Ósea/farmacología , Células de la Médula Ósea/citología , Células Cultivadas , Inhibidores Enzimáticos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Ácido Ibandrónico , Interleucina-1beta/metabolismo , Masculino , Persona de Mediana Edad , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Ligando RANK/genética , Transducción de Señal/fisiología , Células del Estroma/citología
19.
Microsc Microanal ; 16(5): 531-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20813079

RESUMEN

The aim was to characterize the external structure, roughness, and absolute depth profile (ADP) of fluorotic enamel compared with healthy enamel. Eighty extracted human molars were classified into four groups [TFI: 0, control (C); 1-3, mild (MI); 4-5, moderate (MO); 6-9, severe fluorosis (S)] according to the Thylstrup-Fejerskov Index (TFI). All samples were analyzed by atomic force microscopy.The mean values of enamel surface roughness (ESR) in nm were: Group C, 92.6; Group MI, 188.8; Group MO, 246.9; and Group S, 532.2. The mean values of absolute depth profile in nm were: C, 1,065.7; MI, 2,360.7; MO, 2,536.7; and S, 6,146.2. The differences between mean ESR and mean ADP among groups were statistically significant (p < 0.05). This structural study confirms at the nanometer level that there is a positive association between fluorosis severity, ESR, and ADP, and there is an association with the clinical findings of fluorosis measured by TFI as well.


Asunto(s)
Esmalte Dental/ultraestructura , Diente Molar/ultraestructura , Humanos , Microscopía de Fuerza Atómica/métodos , Propiedades de Superficie
20.
Acta Odontol Latinoam ; 23(3): 204-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21638960

RESUMEN

The aim of this study was to examine the association between overweight-obesity and periodontal disease in subjects who attended the clinic of Periodontics, Faculty of Dentistry, San Luis de Potosi, México. This was cross-sectional study involving 88 subjects--60 without overweight-obesity and 28 with overweight-obesity. The following clinical parameters were evaluated: dental bacterial plaque, index of calculus, gingivitis, probing depth and periodontal disease index (PDI). When comparing the group of subjects with overweight-obesity to the control, there were statistically significant differences in the variables calculus (p = 0.0015), gingivitis (p = 0.0050) and periodontal disease (p = 0.0154). Regarding the logistic regression analysis, the dependent variable was subjects with and without overweight-obesity and the independent variables were sex, age and periodontal disease. We found statistically significant differences (p = 0.0162) with OR = 3.16 in periodontal disease. Periodontal disease showed statistically significant differences in the group of subjects with overweight-obesity. The oral health of subjects with overweight-obesity should be supervised and checked in order to prevent oral alterations.


Asunto(s)
Obesidad/complicaciones , Sobrepeso/complicaciones , Enfermedades Periodontales/complicaciones , Adolescente , Adulto , Factores de Edad , Anciano , Índice de Masa Corporal , Peso Corporal , Niño , Estudios Transversales , Cálculos Dentales/complicaciones , Placa Dental/complicaciones , Índice de Placa Dental , Complicaciones de la Diabetes , Femenino , Gingivitis/complicaciones , Humanos , Hipertensión/complicaciones , Masculino , México , Persona de Mediana Edad , Índice Periodontal , Bolsa Periodontal/complicaciones , Factores Sexuales , Circunferencia de la Cintura , Adulto Joven
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