32 results on '"Villalobos MJ"'
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2. Repellent Effects of Coconut Fatty Acid Methyl Esters and Their Blends with Bioactive Volatiles on Winged Myzus persicae (Sulzer) Aphids (Hemiptera: Aphididae).
- Author
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Martín F, Guirao P, and Pascual-Villalobos MJ
- Abstract
Myzus persicae (Sulzer) (Hemiptera: Aphididae) is one of the most important aphid crop pests, due to its direct damage and its ability to transmit viral diseases in crops. The objective is to test whether spraying nanoemulsions of botanical products repels winged individuals of M. persicae in a bioassay in culture chambers. The bioactive volatiles were applied on pepper plants at a dose of 0.2% alone or at 0.1% of each component in blends. A treated plant and a control plant were placed at each side of an entomological cage inside a growth chamber. The winged individuals were released between the plants, in a black-painted Petri dish suspended by wires in the upper half of the cage. The most repellent products were farnesol (repellency index, RI = 40.24%), (E) -anethole (RI = 30.85%) and coconut fatty acid methyl ester (coconut FAME) (RI = 28.93%), alone or in the following blends: farnesol + (E) -anethole + distilled lemon oil (RI = 36.55%) or (E) -anethole + distilled lemon oil + coconut FAME (RI = 30.63%). The observed effect of coconut FAME on aphids is the first report of this product having a repellent effect on a crop pest. Repellent substances for viral disease vectors should be further investigated to develop new strategies for plant protection.
- Published
- 2024
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3. Compatibility of Chrysoperla carnea (Neuroptera: Chrysopidae) with nanoformulations of natural active substances.
- Author
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Dáder B, Magaña AJ, Pascual-Villalobos MJ, Moreno A, Fereres A, and Viñuela E
- Abstract
Nanoformulations of essential oils (EOs) improve stability of the active ingredient, and thereby its biological activity and persistence. Because compatibility of EOs with natural enemies is not explored sufficiently, we evaluated the impact of nanoformulations of EOs (aniseed, lemon) or pure products (farnesol) on different activities of the generalist predator Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). In dual choice bioassay, chrysopid larvae were significantly attracted to aniseed-treated pepper disks and deterred by farnesol. Larval activities (resting, walking, and preying) on treated leaves infested with Myzus persicae (Sulzer) (Hemiptera: Aphididae) were compared. There were no differences among nanoemulsions, nor aphid consumption varied. We studied the toxicity of nanoformulations to larvae and evaluated their development after contact with treated leaf disks, ingestion of treated artificial diet, and both routes of exposure (application of biopesticides on aphid-infested plants). This is the first evidence of the compatibility of EO nanoformulations with C. carnea by single route of exposure. Whether any effect appeared, it was sublethal. Compounds significantly reduced aphid consumption after 6 h on double route exposure, but this negative short-term effect disappeared as time progressed. Our results showed the optimal biopesticide to apply depends on which biological feature of the natural enemy we targeted. The key element to introduce these nanoemulsions is to match their persistence period on the crop with the release of the appropriate biological stage of C. carnea. This reinforces the fact that the main activities of C. carnea can be substantially maintained in joint application with nanoemulsions of EOs., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
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- 2024
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4. The administration of Cerebrolysin elicits neuroprotective and neurorepair effects in an animal model of type 1 diabetes mellitus.
- Author
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Espinoza I, Cabrera F, Morales-Medina JC, Gómez-Villalobos MJ, and Flores G
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- Animals, Male, Streptozocin pharmacology, Disease Models, Animal, Rats, Wistar, Rats, Pyramidal Cells drug effects, Pyramidal Cells pathology, Prefrontal Cortex drug effects, Hippocampus drug effects, Dendritic Spines drug effects, Neuronal Plasticity drug effects, Neurons drug effects, Neuroprotective Agents pharmacology, Neuroprotective Agents administration & dosage, Diabetes Mellitus, Type 1 drug therapy, Amino Acids pharmacology, Amino Acids administration & dosage, Diabetes Mellitus, Experimental drug therapy
- Abstract
Diabetes mellitus (DM) is a metabolic disorder impacting cerebral function. The administration of Streptozotocin (STZ) is a well-known animal model of insulinopenic type 1 DM in rats. STZ-induced DM results in a myriad of alteration in the periphery and central nervous system (CNS). Cerebrolysin (CBL) is a neuropeptide preparation that promotes synaptic and neuronal plasticity in various animal models. In all cases, CBL was administered when the model was established. This research aims to investigate the neuroprotective and neurorepair effect of CBL on the cytoarchitecture of neurons and spine density in pyramidal neurons of the prefrontal (PFC) and the CA1 region of the dorsal hippocampus, as well as spheroidal neurons of the dentate gyrus (DG), in STZ-induced DM. In the first experimental condition, STZ and CBL are administered at the same time to evaluate the potential preventive effect of CBL. In the second experimental condition, CBL was administered two months after establishing the DM model to measure the potential neurorepair effect of CBL. STZ-induced hyperglycemia remained unaltered by the administration of CBL in both experimental conditions. In the first experimental condition, CBL treatment preserved the neuronal morphology in PFC layer 3, PFC layer 5 and the DG of the hippocampus, while also maintaining spine density in the PFC-3, DG and CA1 hippocampus. Furthermore, CBL induced neurorepair in neurons within the PFC-3, PFC-5 and CA1 regions of the hippocampus, along with an increase in spine density in the PFC-3, DG and CA1 hippocampus. These findings suggest that CBL´s effects on neuroplasticity could be observed before or after the damage was evident., Competing Interests: Declaration of Competing Interest The authors have no known conflicts of interest in regard to the materials discussed in this manuscript., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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5. Differential Effects of Neonatal Ventral Hippocampus Lesion on Behavior and Corticolimbic Plasticity in Wistar-Kyoto and Spontaneously Hypertensive Rats.
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Tendilla-Beltrán H, Garcés-Ramírez L, Martínez-Vásquez E, Nakakawa A, Gómez-Villalobos MJ, and Flores G
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- Animals, Rats, Male, Rats, Inbred SHR, Rats, Sprague-Dawley, Rats, Inbred WKY, Animals, Newborn, Prefrontal Cortex, Risperidone, Disease Models, Animal, Hippocampus, Antipsychotic Agents pharmacology
- Abstract
Dysfunction of the corticolimbic system, particularly at the dendritic spine level, is a recognized core mechanism in neurodevelopmental disorders such as schizophrenia. Neonatal ventral hippocampus lesion (NVHL) in Sprague-Dawley rats induces both a schizophrenia-related behavioral phenotype and dendritic spine pathology (reduced total number and mature spines) in corticolimbic areas, which is mitigated by antipsychotics. However, there is limited information on the impact of rat strain on NVHL outcomes and antipsychotic effects. We compared the behavioral performance in the open field, novel object recognition (NORT), and social interaction tests, as well as structural neuroplasticity with the Golgi-Cox stain in Wistar-Kyoto (WKY) and spontaneously hypertensive (SH) male rats with and without NVHL. Additionally, we explored the effect of the atypical antipsychotic risperidone (RISP). WKY rats with NVHL displayed motor hyperactivity without impairments in memory and social behavior, accompanied by dendritic spine pathology in the neurons of the prefrontal cortex (PFC) layer 3 and basolateral amygdala. RISP treatment reduced motor activity and had subtle and selective effects on the neuroplasticity alterations. In SH rats, NVHL increased the time spent in the border area during the open field test, impaired the short-term performance in NORT, and reduced social interaction time, deficits that were corrected after RISP administration. The NVHL caused dendritic spine pathology in the PFC layers 3 and 5 of SH rats, which RISP treatment ameliorated. Our results support the utility of the NVHL model for exploring neuroplasticity mechanisms in schizophrenia and understanding pharmacotherapy., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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6. Neonatal olfactory bulbectomy induces anxiety-related behavior and modifies dopaminergic receptor expression in post-pubertal rats.
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Flores G, Gómez-Villalobos MJ, Iannitti T, and Morales-Medina JC
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- Rats, Animals, Smell, Receptors, Dopamine metabolism, Nucleus Accumbens, Anxiety, Receptors, Dopamine D1 metabolism, Dopamine metabolism, Anti-Anxiety Agents pharmacology
- Abstract
Olfaction is a complex physiological process producing effects in the central nervous system (CNS) and implicated in emotional processes. Indeed, the olfactory bulbs (OB) send projections to various CNS regions including the nucleus accumbens (NAcc) and caudate-putamen (CPu). Both the NAcc and CPu receive important dopaminergic input. Emerging evidence suggests that dopamine (DA) is related to anxiety-related behaviors. Therefore, we aimed to investigate the consequences of neonatal olfactory bulbectomy (nOBX) to anxiety-related behavior as assayed in the elevated plus maze (EPM) as well as the expression of dopaminergic receptors (D1-like, D2-like, and D3) in the NAcc and CPu at pre- and post-pubertal ages in the rat. The results show that nOBX increased the number of entries in the open arm of the EPM post-pubertally, suggesting an anxiolytic-related effect. nOBX increased the D2-like binding in the NAcc shell and D3 binding in the NAcc core pre-pubertally. At post-pubertal ages, the D3 binding was reduced at the olfactory tubercle and islands of Calleja in nOBX rats. Alterations in the DA receptor expression may be one mechanism responsible for the observed behavioral modifications in nOBX rats., (© 2023 Wiley Periodicals LLC.)
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- 2023
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7. Aphicidal activity of farnesol against the green peach aphid - Myzus persicae.
- Author
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Cantó-Tejero M, Guirao P, and Pascual-Villalobos MJ
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- Animals, Crops, Agricultural, Farnesol pharmacology, Pest Control, Biological, Aphids, Insecticides pharmacology, Oils, Volatile pharmacology, Pyrethrins pharmacology
- Abstract
Background: Myzus persicae (Hemiptera: Aphididae) is considered one of most important agricultural pests in the world. It is one of the main pests in protected pepper crops under glasshouse conditions in Southeastern Spain, but its control is limited as a consequence of the few available authorized insecticides and their incompatibility with the natural enemies. Some essential oils and pure compounds such as anise (Pimpinella anisum) or farnesol are repellent and/or toxic to aphids. Their use as a botanical insecticides can be an alternative for aphid control in pepper., Results: The effect of farnesol was evaluated against M. persicae in a new bioassay developed to test the contact effect (aqueous formulation of the products) on aphids in laboratory conditions. Aniseed essential oil, geraniol and (Z)-jasmone at 0.6% causes an aphid mortality of >50%; and farnesol was the most effective (93.67% mortality). Farnesol nanoemulsions between 0.2% and 0.6% were formulated with an IKA-Labor Pilot dispersing machine (7940 rpm for 10 min) using Tween 80 as a surfactant. These formulations were tested on field experiments (glasshouse conditions) on pepper crops for 2 years. Foliar applications of farnesol at a concentration of 0.4% in field conditions causes a high reduction in aphid populations, with efficacies of ≈70-80% with respect to the control, similar to or even higher than the efficacy of the reference pyrethrin insecticide., Conclusion: Farnesol showed a great aphicidal effect against M. persicae. The use of this molecule in integrated pest management programs combined with natural enemies is a good option for future control of M. persicae. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)
- Published
- 2022
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8. Resentment - cultural and individual complex.
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Villalobos MJ
- Subjects
- Child, Female, Humans, Emotions
- Abstract
Resentment is a complex that results from the inability to react to an injustice. The feeling of failure turns into resentment, which incubates until it reaches hatred, indignation and revenge. The unknown parts of the personality, our intolerant side, are relegated to the Shadow. We make a great image of ourselves. It is the Ego Complex. The resentful person feels mistreated by society. He or she has experienced exclusion and physical and mental abuse. When we are resentful, we bring in the god Hephaestus, excluded by both parents. The archetype is manifested by revenge. This complex is characterized by a tetralogy: Ego Complex, Intolerance, Sectarianism, Emotions of revenge and envy., (© 2022 The Society of Analytical Psychology.)
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- 2022
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9. Losartan enhances cognitive and structural neuroplasticity impairments in spontaneously hypertensive rats.
- Author
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Coatl-Cuaya H, Tendilla-Beltrán H, de Jesús-Vásquez LM, Garcés-Ramírez L, Gómez-Villalobos MJ, and Flores G
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- Animals, Blood Pressure, Cognition, Rats, Rats, Inbred SHR, Rats, Inbred WKY, Losartan pharmacology, Neuronal Plasticity
- Abstract
Hypertension is a risk factor for vascular dementia, which is the second most prevalent type of dementia, just behind Alzheimer's disease. This highlights the brain vulnerability due to hypertension, which may increase with aging. Thus, studying how hypertension affects neural cells and behavior, as well as the effects of antihypertensives on these alterations, it's important to understand the hypertension consequences in the brain. The spontaneously hypertensive rat (SHR) has been useful for the study of hypertension alterations in diverse organs, including the brain. Thus, we studied the losartan effects on cognitive and structural neuroplasticity impairments in SHR of 10 months of age. In the first instance, we evaluated the losartan effects on exploratory behavior and novel object recognition test (NORT) in the SHR. Then, we assessed the density and morphology of dendritic spines of pyramidal neurons from the prefrontal cortex (PFC) layers 3 and 5, and CA1 of the dorsal Hp (dHp). Our results indicate that in SHR, losartan treatment (2 months, 15 mg/Kg/day) reduces high blood pressure to age-matched vehicle-treated Wistar-Kyoto (WKY) rat levels. Moreover, losartan improved long-term memory in SHR compared with age-matched vehicle-treated WKY rats, without affecting the locomotor and anxiety behaviors. The behavioral improvement of the SHR can be associated with the increase in the number of dendritic spines and the mushroom spine population in the PFC and the dHp. In conclusion, losartan enhances cognitive impairments by controlling the high blood pressure and improving neuroplasticity in animals with chronic hypertension., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2022
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10. Cerebrolysin ameliorates prefrontal cortex and hippocampus neural atrophy of spontaneous hypertensive rats with hyperglycemia.
- Author
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Aguilar-Hernández L, Gómez-Villalobos MJ, and Flores G
- Subjects
- Amino Acids therapeutic use, Animals, Dendrites drug effects, Dendrites pathology, Hippocampus pathology, Hyperglycemia complications, Hypertension complications, Neuroprotective Agents therapeutic use, Prefrontal Cortex pathology, Rats, Rats, Inbred SHR, Amino Acids pharmacology, Hippocampus drug effects, Hyperglycemia drug therapy, Hypertension drug therapy, Neuroprotective Agents pharmacology, Prefrontal Cortex drug effects
- Abstract
Hyperglycemia of diabetes mellitus causes damage at the vascular level, which at the renal level represents diabetic nephropathy. In this pathology, there is arterial hypertension. In addition, several reports suggest that hyperglycemia and arterial hypertension affect interneuronal communication at the level of dendritic morphology. We studied these changes in an animal model with streptozotocin-induced diabetes mellitus in the spontaneous hypertensive (SH) rat. Recent reports from our laboratory have demonstrated that cerebrolysin (CBL), a preparation of neuropeptides with protective and repairing properties, reduces dendritic deterioration in both pathologies, in separate studies. In the present study, we evaluated the effect of CBL using the animal model with hyperglycemia and arterial hypertension and assessed the dendritic morphology using a Golgi-Cox staining procedure. Our results suggest that CBL ameliorated the reduction in the number of dendritic spines in the PFC and hippocampus caused by hyperglycemia in the SH rat. In addition, CBL also increased distal dendritic length in the PFC and hippocampus in hyperglycemic SH rats. Consequently, the CBL could be a therapeutic tool used to reduce the damage at the level of dendritic communication present in both pathologies., (© 2020 Wiley Periodicals, Inc.)
- Published
- 2020
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11. Protein-conformational diseases in childhood: Naturally-occurring hIAPP amyloid-oligomers and early β-cell damage in obesity and diabetes.
- Author
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Altamirano-Bustamante NF, Garrido-Magaña E, Morán E, Calderón A, Pasten-Hidalgo K, Castillo-Rodríguez RA, Rojas G, Lara-Martínez R, Leyva-García E, Larralde-Laborde M, Domíguez G, Murata C, Margarita-Vazquez Y, Payro R, Barbosa M, Valderrama A, Montesinos H, Domínguez-Camacho A, García-Olmos VH, Ferrer R, Medina-Bravo PG, Santoscoy F, Revilla-Monsalve C, Jiménez-García LF, Morán J, Villalobos-Alva J, Villalobos MJ, Calzada-León R, Altamirano P, and Altamirano-Bustamante MM
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- Adolescent, Animals, Cell Line, Cell Survival, Cells, Cultured, Child, Child, Preschool, Cross-Sectional Studies, Diabetes Mellitus, Type 1 blood, Diabetes Mellitus, Type 2 blood, Diabetes Mellitus, Type 2 complications, Humans, Islet Amyloid Polypeptide blood, Islet Amyloid Polypeptide toxicity, Islet Amyloid Polypeptide ultrastructure, Microscopy, Electron, Transmission, Neurons drug effects, Obesity blood, Obesity complications, Pilot Projects, Primary Cell Culture, Protein Multimerization, Rats, Toxicity Tests, Acute, Diabetes Mellitus, Type 1 pathology, Diabetes Mellitus, Type 2 pathology, Insulin-Secreting Cells pathology, Islet Amyloid Polypeptide metabolism, Obesity pathology, Protein Structure, Quaternary
- Abstract
Background and Aims: This is the first time that obesity and diabetes mellitus (DM) as protein conformational diseases (PCD) are reported in children and they are typically diagnosed too late, when β-cell damage is evident. Here we wanted to investigate the level of naturally-ocurring or real (not synthetic) oligomeric aggregates of the human islet amyloid polypeptide (hIAPP) that we called RIAO in sera of pediatric patients with obesity and diabetes. We aimed to reduce the gap between basic biomedical research, clinical practice-health decision making and to explore whether RIAO work as a potential biomarker of early β-cell damage., Materials and Methods: We performed a multicentric collaborative, cross-sectional, analytical, ambispective and blinded study; the RIAO from pretreated samples (PTS) of sera of 146 pediatric patients with obesity or DM and 16 healthy children, were isolated, measured by sound indirect ELISA with novel anti-hIAPP cytotoxic oligomers polyclonal antibody (MEX1). We carried out morphological and functional studied and cluster-clinical data driven analysis., Results: We demonstrated by western blot, Transmission Electron Microscopy and cell viability experiments that RIAO circulate in the blood and can be measured by ELISA; are elevated in serum of childhood obesity and diabetes; are neurotoxics and works as biomarkers of early β-cell failure. We explored the range of evidence-based medicine clusters that included the RIAO level, which allowed us to classify and stratify the obesity patients with high cardiometabolic risk., Conclusions: RIAO level increases as the number of complications rises; RIAOs > 3.35 μg/ml is a predictor of changes in the current indicators of β-cell damage. We proposed a novel physio-pathological pathway and shows that PCD affect not only elderly patients but also children. Here we reduced the gap between basic biomedical research, clinical practice and health decision making., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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12. Fumigant Toxicity in Myzus persicae Sulzer (Hemiptera: Aphididae): Controlled Release of ( E)- anethole from Microspheres.
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Pascual-Villalobos MJ, Cantó-Tejero M, Guirao P, and López MD
- Abstract
( E) -anethole is a phenylpropanoid that is the main compound found in the essential oils (EOs) of anise and fennel seeds, and either fumigant or direct contact activity of this compound has been demonstrated against aphids and stored product pests. In this work, solid microspheres were prepared by three methods-oil emulsion entrapment, spray-drying, and complexed with β-cyclodextrin. Fumigation activity of each microsphere preparation was tested against the green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), on pepper leaves. The best insecticidal activity was with ( E) -anethole encapsulated in oil emulsion beads and introduced to aphids as a vapour over 24 h, with an LC
50 of 0.415 μL/L compared to 0.336 μL/L of vapors from free ( E) -anethole. Scanning electron microscopy of the beads revealed a compact surface with low porosity that produced a controlled release of the bioactive for more than 21 d, whilst most of the volatile was evaporated within two days if applied unformulated. Spray drying gave spherical particles with the greatest encapsulated yield (73%) of 6.15 g of ( E) -anethole incorporated per 100 g of powder. Further work will be done on improving the formulation methods and testing the solid microspheres in all aphid stages scaling up the experimental assay. It is foreseen that nanotechnology will play a role in future developments of low risk plant protection products., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.- Published
- 2020
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13. A novel Golgi-Cox staining method for detecting and characterizing roles of the hepatic stellate cells in liver injury.
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Gómez Villalobos MJ, Vidrio S, Giles López R, Flores Gómez G, and Chagoya de Sánchez V
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The aim of this study was to investigate the utility of the Golgi-Cox method to characterize the distribution and morphological changes of the hepatic stellate cells (HSCs) in CCl
4 liver damaged rats. Six-week-old male Wistar rats were injected with CCl4 for ten weeks. The livers were processed with the Golgi-Cox method, reticuline, and Massońs Trichrome stains, and analyzed under light microscopy. Histological evaluation of livers was made through the METAVIR score. In normal livers, the HSCs show stellate form with abundant thin cytoplasmic processes, distributed into hepatic lobule, mainly in zone 1. In addition, an intricate and broad network of fibers with radial distribution from the central vein to the periphery of the hepatic lobule was observed. In CCl4 damaged livers, with METAVIR score I and II, HSCs showed a moderate increase in the soma size, in the cytoplasmic processes and in density, distributed in zone 2 and 3; changes associated with a decrease in network fibers. In livers with METAVIR score III and IV, the morphology changes of the HSCs consisted of a significant increase in the soma size, cut and fraying appearance of the emerging cytoplasmic processes, and a decrease in HSCs density, distributed mainly in zone 3, with a significant depletion of network fibers. Results show that Golgi-Cox stain is able to impregnate the HSCs and could be an additional tool to study the morphological changes of the HSCs in the different experimental pathological conditions of the liver., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2017
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14. Burnout prevalence and correlates amongst Colombian dental students: the STRESSCODE study.
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Mafla AC, Villa-Torres L, Polychronopoulou A, Polanco H, Moreno-Juvinao V, Parra-Galvis D, Durán C, Villalobos MJ, and Divaris K
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- Adolescent, Adult, Colombia epidemiology, Educational Measurement, Female, Humans, Male, Odds Ratio, Prevalence, Risk Factors, Socioeconomic Factors, Stress, Psychological, Surveys and Questionnaires, Workload, Young Adult, Burnout, Professional epidemiology, Burnout, Professional psychology, Education, Dental, Students, Dental psychology
- Abstract
Introduction: Accumulating evidence amongst dental students indicates an alarming prevalence of stress, which can precipitate the development of burnout--a state of mental or physical exhaustion and disengagement. Understanding individual and educational correlates of burnout is necessary for its prevention. The aims of this study were to determine the prevalence of burnout amongst a large sample of Colombian dental undergraduates and investigate its psychosocial and educational correlates., Materials and Methods: Survey data collected from 5647 students participating in the Stress in Colombian Dental Education study were used for this analysis. Burnout was measured using the Maslach Burnout Inventory-Student Survey (MBI-SS). Covariates included participants' socio-demographic characteristics and perceived stress, as well as educational environment factors. Descriptive, bivariate and multivariate methods based on multilevel mixed-effects logistic regression modelling were used for data analysis., Results: Seven per cent of the students surveyed met the criteria for burnout. The prevalence of burnout was higher amongst upper classes, older and married students, those who reported not having passed all required courses and not having dentistry as their first career choice, as well as students in public institutions and those with large class sizes. Moreover, students' perceived stress in the domains of workload and self-efficacy was significantly and positively associated with burnout., Conclusions: Both personal and educational environment characteristics were found to be associated with burnout. Irrespective of these factors, students' perceived stress with regard to workload and self-efficacy was a strong influence on burnout and its alleviation may be a promising avenue to prevent psychological morbidity., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2015
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15. Encapsulated Essential Oils as an Alternative to Insecticides in Funnel Traps.
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Pascual-Villalobos MJ, López MD, Castañé C, Soler A, and Riudavets J
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- Animals, Insect Control methods, Insecticides, Moths, Oils, Volatile
- Abstract
Pheromone-lured funnel traps are widely used for pest monitoring and mass trapping in agricultural fields and stores. DDVP vapona (dichlorvos), the insecticide of choice as a killing agent inside traps, has been banned, and research on new products is being pursued. Essential oils (EO) could be an alternative if properly formulated. To test their potential, beads of encapsulated coriander and basil EO were tested in funnel traps in stores of almonds and pet foods during 2 mo. The number of adult moth (Plodia interpunctella (Hübner) and Ephestia kuehniella Zeller) dead captures was similar with either coriander or basil EO beads and with vapona tablets while there were more insects alive in the control. These preliminary results indicate a good potential for the development of such natural products as an alternative to synthetic insecticides to include them inside funnel traps., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2015
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16. Acetylcholinesterase activity of electric eel is increased or decreased by selected monoterpenoids and phenylpropanoids in a concentration-dependent manner.
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López MD, Campoy FJ, Pascual-Villalobos MJ, Muñoz-Delgado E, and Vidal CJ
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- Animals, Anisoles chemistry, Cholinesterase Inhibitors chemistry, Humans, Kinetics, Monoterpenes chemistry, Oils, Volatile chemistry, Oils, Volatile pharmacology, Acetylcholinesterase metabolism, Anisoles pharmacology, Cholinesterase Inhibitors pharmacology, Electrophorus metabolism, Enzyme Activation drug effects, Fish Proteins metabolism, Monoterpenes pharmacology
- Abstract
The profitable insecticidal action of monoterpenoids prompted us to test their efficiency against stored-grain beetle species, via inhibition of acetylcholinesterase (AChE). For this, we first studied the ability of the monoterpenoids geraniol, linalool, camphor, fenchone, carvone and γ-terpinene, besides the phenylpropanoids trans-anethole and estragole to inhibit Electrophorus AChE. The results indicated that while AChE activity increased (15-35%) with 40 μM geraniol, camphor, γ-terpinene and linalool, the activity decreased (60-40%) with 5mM carvone, γ-terpinene, and fenchone. The Km for AChE was 0.52 ± 0.02 mM in control assays, which fell to 0.28 ± 0.01 mM or 0.32 ± 0.01 mM in assays with 20 μM linalool or γ-terpinene added. In the millimolar range, the terpenoids behaved as weak inhibitors. Unexpectedly, AChE inhibition by camphor, carvone, γ-terpinene, and fenchone gave Hill numbers ranging 2.04-1.57, supporting the idea that AChE was able to lodge more than one monoterpenoid molecule. The plots of 1/v vs. 1/S at varying monoterpenoid provided straight lines, fenchone and γ-terpinene acting as competitive inhibitors and carvone and camphor as non-competitive inhibitors. Moreover, the secondary plots of the slope KM(app)/Vmax(app) vs. [I] and of 1/Vmax(app) vs. [I] gave parabolic curves, which lent support to the proposed capacity of AChE to bind more than one monoterpenoid molecule. The fitting of the curves to a second-order polynomial equation allowed us to calculate the inhibition constants for the interaction of AChE with fenchone, γ-terpinene, carvone and camphor. The previously unnoticed increase in AChE activity with monoterpenoids should be considered as a reminder when advising the use of essential oils of plants or their constituents as anti-AChE agents to attenuate pathological signs of Alzheimer's disease., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2015
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17. Comparative mortality of diapausing and nondiapausing larvae of Plodia interpunctella (Lepidoptera: Pyralidae) exposed to monoterpenoids and low pressure.
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Mbata GN, Pascual-Villalobos MJ, and Payton ME
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- Air Pressure, Animals, Larva drug effects, Larva growth & development, Larva physiology, Moths growth & development, Moths physiology, Temperature, Time Factors, Insect Control methods, Monoterpenes pharmacology, Moths drug effects
- Abstract
Monoterpenoids and low pressure have each been demonstrated to cause mortality of stored-product insect pests. The current report investigated the prospects of integrating the two methods in the management of diapausing and nondiapausing larvae of Plodia interpunctella (Hübner). In a separate experiment, the larvae were exposed to 35.5 mmHg in Erlenmeyer flasks at 19 and 28 degrees C for times ranging from 30 min to 96 h. Another set of experiments was conducted to investigate the toxicity of exposing P. interpunctella larvae to monoterpenoids including E-anethole, estragole, S-carvone, linalool, L-fenchone, geraniol, gamma-terpinene, and DL-camphor alone or in combination with low pressure (50 mmHg). Lethal times (LT) determined by subjecting time-mortality data to probit analyses were shortened to half when both diapausing and nondiapausing larvae were exposed to low pressure at 28 degrees C compared with 19 degrees C. Exposure of diapausing larvae to a monoterpenoid alone, with the exception of DL-camphor and estragole, at a concentration of 66.7 microl/1L of volume required > 30 h to generate 99% mortality at 19.0 +/- 0.8 degrees C. However, the LT99 values for diapausing and nondiapausing larvae exposed to combinations of DL-camphor or estragole and low pressure were considerably shortened. Combinations involving the rest of the monoterpenoids investigated and low pressure did not generate LT99 that were shorter than those of the control, which was low pressure only. These results suggest that integrating low pressure with DL-camphor or estragole could be a new method for the control of diapausing larvae of P. interpunctella at cooler temperatures.
- Published
- 2012
- Full Text
- View/download PDF
18. Development of formulations to improve the controlled-release of linalool to be applied as an insecticide.
- Author
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Lopez MD, Maudhuit A, Pascual-Villalobos MJ, and Poncelet D
- Subjects
- Acyclic Monoterpenes, Capsules chemistry, Chemistry, Pharmaceutical, Drug Stability, Emulsions chemistry, Kinetics, Delayed-Action Preparations chemistry, Drug Compounding methods, Insecticides chemistry, Monoterpenes chemistry
- Abstract
In recent studies, insecticide activity of a monoterpene, linalool, has been demonstrated, finding, however, limitations in application because of its rapid volatilization. Potential effectiveness of microcapsules and effects of various types of matrices on its stability as controlled-release systems for the slow volatilization of linalool to be applied as insecticide were evaluated. To study controlled-release, linalool was entrapped into microcapsules, inclusion complexes, and beads, obtained by different methods, inverse gelation (IG1, IG2, IG3, IG4, and IG5), oil-emulsion-entrapment (OEE), interfacial coacervation (INCO), and chemical precipitation (Cyc5 and Cyc10). The encapsulation yield turned out to be different for each formulation, reaching the maximum retention for IG1 and OEE. In controlled-release, OEE followed by INCO presented a long time necessary for releasing as a result of the presence of glycerol or chitosan. These results pointed out remarkable differences in the release behavior of linalool depending on matrix composition and the method of encapsulation.
- Published
- 2012
- Full Text
- View/download PDF
19. Type 1 diabetes-induced hyper-responsiveness to 5-hydroxytryptamine in rat pulmonary arteries via oxidative stress and induction of cyclooxygenase-2.
- Author
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Lopez-Lopez JG, Moral-Sanz J, Frazziano G, Gomez-Villalobos MJ, Moreno L, Menendez C, Flores-Hernandez J, Lorente JA, Cogolludo A, and Perez-Vizcaino F
- Subjects
- Animals, Bone Morphogenetic Protein Receptors, Type II metabolism, Diabetes Mellitus, Type 1 enzymology, Endothelium, Vascular drug effects, Enzyme Induction drug effects, Enzyme Induction physiology, Male, Oxidative Stress drug effects, Pulmonary Artery drug effects, Rats, Rats, Sprague-Dawley, Serotonin pharmacology, Vasoconstriction drug effects, Vasoconstriction physiology, Cyclooxygenase 2 biosynthesis, Diabetes Mellitus, Type 1 metabolism, Endothelium, Vascular metabolism, Oxidative Stress physiology, Pulmonary Artery metabolism, Serotonin metabolism
- Abstract
Recent epidemiological data suggest that diabetes is a risk factor for pulmonary arterial hypertension. The aim of the present study was to analyze the link between type 1 diabetes and pulmonary arterial dysfunction in rats. Male Sprague-Dawley rats were randomly divided into a control group (saline) and a diabetic group (70 mg/kg streptozotocin). After 6 weeks, diabetic animals showed a down-regulation of the lung bone morphogenetic protein receptor type 2, up-regulation of 5-hydroxytryptamine (5-HT) 2A receptors and cyclooxygenase-2 (COX-2) proteins as measured by Western blot analysis, and increased contractile responses to 5-HT in isolated intrapulmonary arteries. The hyper-responsiveness to 5-HT was endothelium-independent and unaffected by inhibition of nitric-oxide synthase but prevented by indomethacin, the selective COX-2 inhibitor N-[2-(cyclohexyloxyl)-4-nitrophenyl]-methane sulfonamide (NS-398), superoxide dismutase, and the NADPH oxidase inhibitor apocynin or chronic treatment with insulin. However, diabetic rats at 6 weeks did not develop elevated right ventricular pressure or pulmonary artery muscularization, whereas a longer exposure (4 months) to diabetes induced a modest, but significant, increase in right ventricular systolic pressure. In conclusion, type 1 diabetes mellitus in rats induces a number of changes in lung protein expression and pulmonary vascular reactivity characteristic of clinical and experimental pulmonary arterial hypertension but insufficient to elevate pulmonary pressure. Our results further strengthen the link between diabetes and pulmonary arterial hypertension.
- Published
- 2011
- Full Text
- View/download PDF
20. The utility of the Golgi-Cox method in the morphological characterization of the autonomic innervation in the rat heart.
- Author
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Gómez-Villalobos MJ, Gordillo AC, López JR, and Flores G
- Subjects
- Animals, Heart anatomy & histology, Male, Photomicrography, Rats, Rats, Wistar, Autonomic Pathways anatomy & histology, Heart innervation, Neurons cytology, Staining and Labeling methods
- Abstract
The autonomic innervation in the heart is predominantly by postganglionic, parasympathetic, and sympathetic neurons, which are organized in a plexus of ganglions into the heart. The knowledge of the density, distribution, location, morphology, and intrinsic connection of this system that constitute the heart autonomic innervation is limited and controversial. Methods that provide clear information in this field are desirable. A widely used method to study the morphology of the nerve cells in the central nervous system (CNS) is used in this study to characterize the autonomic innervation in rat hearts. The method consisted of impregnation of the fresh whole heart of 12 adult male Wistar rats with the Golgi-Cox stain for 30 days, after which they were incubated in 30% sucrose solution for 2-3 days and then were sectioned (200 microm) with a vibratome. The tissues were mounted on gelatin-covered slides and analyzed by using the Sholl method under light microscopy adapted to a camera lucida. The results clearly show a distribution of the ganglion plexuses in the epicardium, myocardium, and endocardium, joined by an extensive network of nerve fibers in the four cardiac chambers. We also identified and characterized the morphology of an isolated cardiac nerve cell. As results similar to that in the CNS, the Golgi-Cox method is a simple, efficient, and an accessible tool to study the autonomic innervation in the rat heart and provides a good resolution of the morphology of the plexuses of the ganglions and nerve fibers.
- Published
- 2009
- Full Text
- View/download PDF
21. Diabetes induces pulmonary artery endothelial dysfunction by NADPH oxidase induction.
- Author
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Lopez-Lopez JG, Moral-Sanz J, Frazziano G, Gomez-Villalobos MJ, Flores-Hernandez J, Monjaraz E, Cogolludo A, and Perez-Vizcaino F
- Subjects
- Acetylcholine pharmacology, Animals, Diabetes Mellitus pathology, Endothelium drug effects, Endothelium pathology, Enzyme Induction drug effects, In Vitro Techniques, Male, NG-Nitroarginine Methyl Ester pharmacology, Nitric Oxide metabolism, Pulmonary Artery drug effects, Pulmonary Artery pathology, Rats, Rats, Sprague-Dawley, Superoxides metabolism, Vasodilation drug effects, Diabetes Mellitus enzymology, Diabetes Mellitus physiopathology, Endothelium enzymology, Endothelium physiopathology, NADPH Oxidases biosynthesis, Pulmonary Artery enzymology, Pulmonary Artery physiopathology
- Abstract
Recent data suggest that diabetes is a risk factor for pulmonary hypertension. The aim of the present study was to analyze whether diabetes induces endothelial dysfunction in pulmonary arteries and the mechanisms involved. Male Sprague-Dawley rats were randomly divided into a control (saline) and a diabetic group (70 mg/kg(-1) streptozotocin). After 6 wk, intrapulmonary arteries were mounted for isometric tension recording, and endothelial function was tested by the relaxant response to acetylcholine. Protein expression and localization were measured by Western blot and immunohistochemistry and superoxide production by dihydroethidium staining. Pulmonary arteries from diabetic rats showed impaired relaxant response to acetylcholine and reduced vasoconstrictor response to the nitric oxide (NO) synthase inhibitor L-NAME, whereas the response to nitroprusside and the expression of endothelial NO synthase remained unchanged. Endothelial dysfunction was reversed by addition of superoxide dismutase or the NADPH oxidase inhibitor apocynin. An increase in superoxide production and increased expression of the NADPH oxidase regulatory subunit p47(phox) were also found in pulmonary arteries from diabetic rats. In conclusion, the pulmonary circulation is a target for diabetes-induced endothelial dysfunction via enhanced NADPH oxidase-derived superoxide production.
- Published
- 2008
- Full Text
- View/download PDF
22. Detection of DNA double-strand breaks and chromosome translocations using ligation-mediated PCR and inverse PCR.
- Author
-
Villalobos MJ, Betti CJ, and Vaughan AT
- Subjects
- Cells, Cultured, DNA drug effects, DNA radiation effects, DNA Damage, DNA Primers chemistry, Humans, Chromosome Breakage, DNA analysis, DNA Repair, Polymerase Chain Reaction methods, Translocation, Genetic
- Abstract
Current techniques for examining the global creation and repair of DNA double-strand breaks are restricted in their sensitivity, and such techniques mask any site-dependent variations in breakage and repair rate or fidelity. We present here a system for analyzing the fate of documented DNA breaks, using the MLL gene as an example, through application of ligation-mediated PCR. Here, a simple asymmetric double-stranded DNA adapter molecule is ligated to experimentally induced DNA breaks and subjected to seminested PCR using adapter and gene-specific primers. The rate of appearance and loss of specific PCR products allows detection of both the break and its repair. Using the additional technique of inverse PCR, the presence of misrepaired products (translocations) can be detected at the same site, providing information on the fidelity of the ligation reaction in intact cells. Such techniques may be adapted for the analysis of DNA breaks introduced into any identifiable genomic location.
- Published
- 2006
- Full Text
- View/download PDF
23. Cleavage of the MLL gene by activators of apoptosis is independent of topoisomerase II activity.
- Author
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Betti CJ, Villalobos MJ, Jiang Q, Cline E, Diaz MO, Loredo G, and Vaughan AT
- Subjects
- Amino Acid Motifs, Binding Sites, Cell Line, Tumor, Histone-Lysine N-Methyltransferase, Humans, Nuclear Matrix-Associated Proteins, Oncogene Proteins, Fusion genetics, Proto-Oncogene Proteins c-bcr genetics, Transfection, Apoptosis, DNA Topoisomerases, Type II metabolism, Gene Rearrangement, Myeloid-Lymphoid Leukemia Protein genetics, Sequence Deletion
- Abstract
Exposure to topoisomerase II inhibitors is linked to the generation of leukemia involving translocations of the MLL gene, normally restricted to an 8.3 kbp tract, the breakpoint cluster region (BCR). Using an in vitro assay, apoptotic activators, including radiation and anti-CD95 antibody, trigger site-specific cleavage adjacent to exon 12 within the MLL BCR and promote translocation of the MLL gene in cells that can survive. To explore the mechanism of cleavage and rearrangement in more detail, the entire MLL BCR was placed into the pREP4 episomal vector and transfected into human lymphoblastoid TK6 cells. Episomes containing either the MLL BCR, or deletion constructs of 367 bp or larger, were cleaved at the same position as genomic MLL after exposure to apoptotic stimuli. Further analysis of sequence motifs surrounding the cleaved region of MLL showed the presence of both a predicted nuclear matrix attachment sequence and a potential strong binding site for topoisomerase II, flanking the site of cleavage. Inactivation of topoisomerase II by the catalytic inhibitor merbarone did not inhibit MLL cleavage, suggesting that the initial cleavage step for MLL rearrangement is not mediated by topoisomerase II.
- Published
- 2005
- Full Text
- View/download PDF
24. Surviving apoptosis: a possible mechanism of benzene-induced leukemia.
- Author
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Vaughan AT, Betti CJ, Villalobos MJ, Premkumar K, Cline E, Jiang Q, and Diaz MO
- Subjects
- Animals, DNA Damage, DNA-Binding Proteins genetics, Histone-Lysine N-Methyltransferase, Humans, Models, Biological, Myeloid-Lymphoid Leukemia Protein, Proto-Oncogenes genetics, Transcription Factors genetics, Apoptosis, Benzene toxicity, DNA-Binding Proteins metabolism, Leukemia chemically induced, Transcription Factors metabolism
- Abstract
The pathological consequences resulting from deregulation of the apoptotic program include cancer (too little apoptosis) or diseases of cell deprivation, such as Alzheimer's (too much apoptosis). We have identified an additional pathology whereby cells reaching the earliest stage of chromatin cleavage have the potential to suppress apoptotic execution and survive. One specific cleavage event associated with this process is restricted to a location within the mixed lineage leukemia (MLL) gene at 11q23. The site of cleavage is consistent with the location where large, approximately 50 kbp loops of supercoiled DNA are attached to the nuclear matrix. Cells modified by this process generate MLL translocations, as shown by inverse PCR, that survive for days to weeks but which have no known relationship with clinical disease. Using a specific approach, cells stimulated by anti-CD95 antibody, a potent stimulator of the apoptotic program, facilitated creation of the MLL-AF9 fusion gene. Further, this rearrangement, which is commonly observed in patients with AML linked to exposure to cytotoxic agents, was efficiently transcribed in cells that were able to undergo cell division. These data are discussed in the context of benzene and benzene metabolite toxicity that impacts the process of apoptosis and is known to lead to leukemic disease.
- Published
- 2005
- Full Text
- View/download PDF
25. Detection of DNA double-strand breaks and chromosome translocations using ligation-mediated PCR and inverse PCR.
- Author
-
Villalobos MJ, Betti CJ, and Vaughan AT
- Subjects
- Animals, DNA analysis, DNA genetics, DNA-Binding Proteins genetics, Histone-Lysine N-Methyltransferase, Humans, Myeloid-Lymphoid Leukemia Protein, Proto-Oncogenes genetics, Transcription Factors genetics, Chromosome Breakage genetics, DNA Damage, Polymerase Chain Reaction methods, Translocation, Genetic genetics
- Abstract
Current techniques for examining the global creation and repair of DNA double-strand breaks are restricted in their sensitivity, and such techniques mask any site-dependent variations in breakage and repair rate or fidelity. We present here a system for analyzing the fate of documented DNA breaks, using the MLL gene as an example, through application of ligation-mediated PCR. Here, a simple asymmetric double-stranded DNA adapter molecule is ligated to experimentally induced DNA breaks and subjected to seminested PCR using adapter and gene-specific primers. The rate of appearance and loss of specific PCR products allows detection of both the break and its repair. Using the additional technique of inverse PCR, the presence of misrepaired products (translocations) can be detected at the same site, providing information on the fidelity of the ligation reaction in intact cells. Such techniques may be adapted for the analysis of DNA breaks introduced into any identifiable genomic location.
- Published
- 2005
- Full Text
- View/download PDF
26. Apoptotic stimuli initiate MLL-AF9 translocations that are transcribed in cells capable of division.
- Author
-
Betti CJ, Villalobos MJ, Diaz MO, and Vaughan AT
- Subjects
- Cell Division genetics, Cell Line, Chromosome Breakage, DNA-Binding Proteins biosynthesis, Histone-Lysine N-Methyltransferase, Humans, Introns, Lymphocytes cytology, Lymphocytes metabolism, Lymphocytes physiology, Myeloid-Lymphoid Leukemia Protein, Nuclear Proteins biosynthesis, Oncogene Proteins, Fusion biosynthesis, Oncogene Proteins, Fusion genetics, Polymerase Chain Reaction methods, Signal Transduction physiology, Transcription, Genetic, fas Receptor physiology, Apoptosis genetics, DNA-Binding Proteins genetics, Nuclear Proteins genetics, Proto-Oncogenes, Transcription Factors, Translocation, Genetic
- Abstract
Activation of apoptosis introduces a site-specific break within intron 11 of the MLL gene. Using the CD95 apoptotic signaling pathway in human lymphoblastoid cells, the 5' fragment of MLL undergoes translocation to intron 4 of AF9 and the proleukemogenic MLL-AF9 fusion gene created is transcribed. Both the breaks in MLL and transcription of the MLL-AF9 fusion gene are suppressed in the presence of the broad spectrum caspase inhibitor, zVAD.fmk. Duplicate cells containing sequence identical MLL-AF9 fusion junctions were identified within a cell population that had recovered from apoptosis. This indicated that cells harboring a translocation initiated by apoptotic cleavage had divided. These data are consistent with a novel pathogenic role for the apoptotic program where translocations with leukemogenic potential are created within cells that have the capacity to divide.
- Published
- 2003
27. A new 24-nor-oleanane triterpenoid from Salvia carduacea.
- Author
-
Ballesta-Acosta MC, Pascual-Villalobos MJ, and Rodríguez B
- Subjects
- Molecular Structure, Spectrum Analysis, Triterpenes chemistry, Salvia chemistry, Triterpenes isolation & purification
- Abstract
A new triterpenoid (1) has been isolated from the acetone extract of the leaves of Salvia carduacea, together with other compounds described previously. The structure of 1 [2alpha,3alpha-dihydroxy-24-nor-4(23),12-oleanadien-28-oic acid] was elucidated by spectroscopic methods, particularly by extensive 1D and 2D NMR studies.
- Published
- 2002
- Full Text
- View/download PDF
28. Surviving apoptosis.
- Author
-
Vaughan AT, Betti CJ, and Villalobos MJ
- Subjects
- Animals, Caspase 3, Caspases metabolism, DNA Damage, Enzyme Activation, Humans, Models, Biological, Protein Transport, Apoptosis
- Abstract
The concept that cells subjected to chromatin cleavage during apoptosis are destined to die is being challenged. The execution phase of apoptosis is characterized by the activation of effector caspases, such as caspase-3, that cleave key regulatory or structural proteins and in particular activate apoptotic nucleases such as the caspase activated deoxyribonuclease (CAD). It is apparent that caspases of this type may become active both through non-apoptotic processing and potentially within cells that exhibit apoptotic morphology but are subsequently able to survive. In such systems caspase suppressor molecules, the inhibitors of apoptotic proteins or IAP's, may rescue cells from apoptotic nuclease(s) attack initiated by transient caspase activation. The MLL gene is involved in leukemogenic translocations in ALL and AML and is a target of nuclease cleavage during apoptosis. Translocations initiated at the site of apoptotic nuclease attack within MLL have been identified and may offer a model, with clinical relevance, for DNA damage mediated by the apoptosis system in cells destined to survive. The specificity of apoptotic cleavage combined with the potential for recovery from the execution phase of apoptosis suggests a novel and pathogenic role for apoptosis in creating translocations with leukemogenic potential.
- Published
- 2002
- Full Text
- View/download PDF
29. Apoptotic triggers initiate translocations within the MLL gene involving the nonhomologous end joining repair system.
- Author
-
Betti CJ, Villalobos MJ, Diaz MO, and Vaughan AT
- Subjects
- DNA genetics, DNA metabolism, DNA radiation effects, DNA Damage, DNA-Activated Protein Kinase, Histone-Lysine N-Methyltransferase, Humans, Lymphocytes cytology, Lymphocytes diagnostic imaging, Lymphocytes physiology, Myeloid-Lymphoid Leukemia Protein, Nuclear Proteins, Oncogene Proteins genetics, Protein Serine-Threonine Kinases antagonists & inhibitors, Protein Serine-Threonine Kinases metabolism, Proto-Oncogene Proteins c-bcr, Radiography, Translocation, Genetic, Apoptosis physiology, DNA Repair physiology, DNA-Binding Proteins genetics, Protein-Tyrosine Kinases, Proto-Oncogene Proteins, Proto-Oncogenes, Transcription Factors
- Abstract
Translocations involving the MLL gene at 11q23 are a frequent finding in therapy-related leukemia and are concentrated within a short, 8.3-kb tract of DNA, the breakpoint cluster region. In addition, a specific site adjacent to exon 12 within this region of MLL is cleaved in cells undergoing apoptosis. We show here, using human TK6 lymphoblastoid cells, that irradiation and the apoptotic trigger anti-CD95 antibody are each able to initiate translocations at the MLL exon 12 cleavage site. The translocation junctions produced contain regions of microhomology consistent with operation of the nonhomologous end joining (NHEJ) repair process. Participation of the NHEJ process is supported by the identification of the NHEJ component DNA-PKcs at the site of apoptotic cleavage. Suppression of DNA-PKcs function by the phosphatidylinositol 3-kinase inhibitor wortmannin compromises DNA end joining, increases site-specific cleavage within MLL, and eliminates MLL-restricted translocations. We propose that activation of apoptotic effector nucleases alone is sufficient to generate proleukemogenic translocations and raises the possibility that some of these may persist in cells that evade apoptotic execution and survive.
- Published
- 2001
30. Antifungal activity of the essential oil of flowerheads of garland chrysanthemum (Chrysanthemum coronarium) against agricultural pathogens.
- Author
-
Alvarez-Castellanos PP, Bishop CD, and Pascual-Villalobos MJ
- Subjects
- Microbial Sensitivity Tests, Antifungal Agents pharmacology, Asteraceae chemistry, Crops, Agricultural microbiology, Fungi drug effects, Oils, Volatile pharmacology
- Abstract
The antifungal activity of Chrysamthemum coronarium was evaluated against 12 agricultural pathogens. Flowerhead oil was active both in contact and headspace in vitro assays producing hyphal growth inhibition, although there was less activity on faster growing fungi. The main compounds identified in the oil were camphor (29.2%), alpha-pinene (14.8%), beta-pinene (9.5%) and lyratyl acetate (9.8%). The blue color of the oil was due to the presence of chamazulene (0.5%).
- Published
- 2001
- Full Text
- View/download PDF
31. [Effect of acute myocardial ischemia on pulmonary venous flow pattern. Experimental study with transesophageal echocardiography].
- Author
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Gómez-Villalobos MJ, Hernández-Herrera C, Espinola-Zavaleta N, Jiménez Sivira R, Romero-Cárdenas A, Rylaarsdam M, and Vargas-Barrón J
- Subjects
- Acute Disease, Animals, Dogs, Female, Male, Echocardiography, Transesophageal, Myocardial Ischemia physiopathology, Pulmonary Circulation physiology, Pulmonary Veins diagnostic imaging
- Abstract
Pulmonary venous flow (PVF) has been analyzed by Doppler echocardiography in various cardiopathies, but up to now no studies of its behavior in acute myocardial ischemia have been reported. The purpose of this study is to describe the changes observed in the normal pattern of PVF with myocardial ischemia in an experimental model. Thoracotomy and pericardiectomy with exposure of the heart were performed on 19 mongrel dogs, weighing between 18 and 25 kg anesthetized with intravenous sodium pentobarbital. Pulmonary venous and mitral flows were analyzed by transesophageal echocardiography with pulsed Doppler and simultaneous recording of intracavitary pressures in left atrium (LA) and left ventricle (LV) before and after 30 minutes of partial occlusion of the middle portion of the anterior descending coronary artery distal to the first diagonal branch. The variables examined included maximal velocities and time-velocity integrals of antegrade systolic(s) and diastolic (D) PVF, mitral rapid filling flow (E) and left ventricular isovolumic relaxation time (LVIRT). The pressures directly measured were mean left atrial pressure (MLAP), systolic and diastolic pressures of the LV. Results included a decrease in peak velocities and time-velocity integrals of PVF (S and D) with myocardial ischemia, S velocity from 70.1 +/- 14.8 to 49.5 +/- 13.8 cm/sec (p < 0.001) and D from 41.4 +/- 16.5 to 29.5 +/- 11.4 cm/sec (p = 0.001), with an increase in LVIRT from 65.8 +/- 8.6 to 76.0 +/- 12.6 msec (p < 0.006) and elevation of the mean pressure of the LA from 4.3 +/- 1.0 to 6.4 +/- 1.5 mmHg (p < 0.001). This findings suggest that acute myocardial ischemia alters the normal pattern of PVF, producing a significant decrease in peak velocities and time-velocity integrals of antegrade systolic and diastolic flows as well as an increase in LVIRT and MLAP, which taken together may reflect altered diastolic function of the LV.
- Published
- 1995
32. [Changes in the vasoconstrictor action of noradrenaline and in its receptor-binding kinetics induced by sex hormones].
- Author
-
Ceballos GM, Gómez Villalobos MJ, Recamier LM, Trujillo J, Yañez R, and Pastelín G
- Subjects
- Animals, Carotid Arteries drug effects, Carotid Arteries metabolism, Dogs, Dose-Response Relationship, Drug, Drug Interactions, In Vitro Techniques, Male, Norepinephrine pharmacokinetics, Receptors, Adrenergic metabolism, Vasoconstriction drug effects, Vasoconstrictor Agents pharmacokinetics, Estradiol pharmacology, Norepinephrine pharmacology, Receptors, Adrenergic drug effects, Testosterone pharmacology, Vasoconstrictor Agents pharmacology
- Abstract
The role of testosterone/17 B estradiol ratios (T/E), on the vasoconstrictor effect of norepinephrine (NE), were studied in strips of carotid arteries from dogs. T/E of 0.1 (T = 1 nM/E = 10 nM) shifted the concentration/effect (C-E) curve of NE to the right. T/E of 10 (T = 10 nM/E = 1 nM) deviated it to the left. T (1 nM and 10 nM) shifted the C-E curve of NE to the right; E = 1 nM did not modify it; E = 10 nM, shifted it to the left. In microsomal fraction of carotid arteries, adrenergic receptors were characterized with 3H-NE binding, and the role of T/E ratios also studied. Under the influence of T/E ratio of 10, the agonist affinity (Ka), was increased from 100 nM-1 to 128 nM-1, the receptors density (Bmax), increased from 78.3 nM to 148 nM. E (1 nM) reduced Ka to 88 nM-1, T did not change any of these parameters. In conclusion, T/E ratios of 10, as in male, may enhance the vasoconstrictor activity of NE, increasing Ka and Bmax of adrenergic receptors.
- Published
- 1991
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