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1.
Psychol Res ; 85(3): 1016-1028, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32036442

RESUMEN

Recent research reveals that when faced with alternative lines of action, humans tend to choose the less cognitively demanding one, suggesting that cognitive control is intrinsically registered as costly. This idea is further supported by studies showing that the exertion of cognitive control evokes negative affective states. Despite extensive evidence for mood-induced modulations on control abilities, the impact of affective states on the avoidance of cognitive demand is still unknown. Across two well-powered experiments, we tested the hypothesis that negative affective states would increase the avoidance of cognitively demanding tasks. Contrary to our expectations, induced affective states did not modulate the avoidance of demand, despite having an effect on task performance and subjective experience. Altogether, our results indicate that there are limits to the effect of affective signals on cognitive control and that such interaction might depend on specific affective and control settings.


Asunto(s)
Reacción de Prevención/fisiología , Cognición/fisiología , Emociones/fisiología , Trastornos del Humor/fisiopatología , Análisis y Desempeño de Tareas , Adolescente , Adulto , Femenino , Humanos , Masculino , España , Adulto Joven
2.
Glob Chang Biol ; 26(7): 3880-3890, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32315464

RESUMEN

Coral reefs worldwide are threatened by thermal stress caused by climate change. Especially devastating periods of coral loss frequently occur during El Niño-Southern Oscillation (ENSO) events originating in the Eastern Tropical Pacific (ETP). El Niño-induced thermal stress is considered the primary threat to ETP coral reefs. An increase in the frequency and intensity of ENSO events predicted in the coming decades threatens a pan-tropical collapse of coral reefs. During the 1982-1983 El Niño, most reefs in the Galapagos Islands collapsed, and many more in the region were decimated by massive coral bleaching and mortality. However, after repeated thermal stress disturbances, such as those caused by the 1997-1998 El Niño, ETP corals reefs have demonstrated regional persistence and resiliency. Using a 44 year dataset (1970-2014) of live coral cover from the ETP, we assess whether ETP reefs exhibit the same decline as seen globally for other reefs. Also, we compare the ETP live coral cover rate of change with data from the maximum Degree Heating Weeks experienced by these reefs to assess the role of thermal stress on coral reef survival. We find that during the period 1970-2014, ETP coral cover exhibited temporary reductions following major ENSO events, but no overall decline. Further, we find that ETP reef recovery patterns allow coral to persist under these El Niño-stressed conditions, often recovering from these events in 10-15 years. Accumulative heat stress explains 31% of the overall annual rate of change of living coral cover in the ETP. This suggests that ETP coral reefs have adapted to thermal extremes to date, and may have the ability to adapt to near-term future climate-change thermal anomalies. These findings for ETP reef resilience may provide general insights for the future of coral reef survival and recovery elsewhere under intensifying El Niño scenarios.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Cambio Climático , Ecuador , El Niño Oscilación del Sur
3.
J Pers Assess ; 101(1): 84-95, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-28933921

RESUMEN

Although cheerfulness, seriousness, and bad mood as traits have been widely studied as the basis of sense of humor, data are scarce regarding the same dimensions as states. In this study, we adapted the state form of the State-Trait-Cheerfulness Inventory (STCI-S) into Spanish. At the same time, we empirically tested new predictions. We assessed 5 independent samples accounting for 1,029 participants (647 women) with ages ranging from 18 to 78 years. We confirmed the 3-dimensional structure as well as a strong measurement invariance between men and women. The internal consistency of the scale was satisfactory, the expected intercorrelations emerged, and the convergence between states and traits was corroborated. We also confirmed that the STCI-S's items were sensitive to affective changes in the environment. A longitudinal stability study of the state-trait dimensions using latent state-trait (LST) models revealed that all three trait measures capture mostly stable interindividual differences, with occasion-specific effects mainly in the state dimensions. Finally, we found that the STCI-S dimensions were related to state well-being. The results suggest that the STCI-S is a valid option for measuring the state basis of sense of humor in the Spanish population.


Asunto(s)
Risoterapia/métodos , Personalidad , Temperamento , Adulto , Anciano , Cognición , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida/psicología , Reproducibilidad de los Resultados , Adulto Joven
4.
Psychol Res ; 78(2): 196-208, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23689476

RESUMEN

The aim of this paper was to study whether real angry faces do capture attention to the extent of overcoming the inhibition of return (IOR) effect and whether the anxiety level of participants modulates this effect by stressing biases toward threatening stimuli. With this purpose, participants categorized the emotional valence of face targets in a standard spatial cueing procedure suitable to measure IOR. In Experiment 1, participants were selected according to their high vs. low-trait anxiety, whereas in Experiment 2 participants were induced a positive vs. anxiety mood state. The typical IOR effect was observed with neutral and happy face targets, which disappeared with angry face targets. Similar results were observed for all anxiety groups and in both experiments. The results indicate that IOR is overridden when the target is a biologically relevant angry face, as highly relevant targets should suffer less from habituation to attentional capture regardless of anxiety. We suggest that these data show that attentional capture is less likely to habituate for threatening information, so that no cost is measured in detecting new threatening information appearing at recently cued locations.


Asunto(s)
Ira , Ansiedad/fisiopatología , Atención/fisiología , Expresión Facial , Habituación Psicofisiológica/fisiología , Inhibición Psicológica , Adolescente , Adulto , Señales (Psicología) , Cara , Femenino , Humanos , Masculino , Personalidad , Estimulación Luminosa , Tiempo de Reacción , Adulto Joven
5.
J Travel Med ; 31(3)2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38206875

RESUMEN

BACKGROUND: PfSPZ vaccines comprising Plasmodium falciparum (Pf) sporozoites (SPZ) have demonstrated > 90% protection against variant Pf malaria infections for at least 12 weeks; they are the only vaccines with the level of efficacy necessary to protect travellers. PfSPZ are eukaryotic cells stabilized by cryopreservation and distributed using a cryogenic (below -150 °C) cold chain. The Ebola vaccine and mRNA vaccines against SARS-CoV-2 pioneered uptake of vaccines requiring non-standard ultra-low temperature cold chains. The cryogenic cold chain using liquid nitrogen (LN2) vapour phase (LNVP) cryoshippers, is simpler, more efficient than -80, -20 or 2-8 °C cold chains, and does not use electricity. This study was conducted to evaluate implementation and integration of a cryogenically distributed vaccine at travel and military immunization clinics. METHODS: We conducted sequential 28-day studies evaluating vaccine shipping, storage, maintenance and accession at two US military and two civilian travel health/immunization clinics. In each clinic, personnel were trained in equipment use, procurement and handling of LN2, temperature monitoring and inventory record keeping by in-person or video instruction. RESULTS: Sites required 2-4 h/person for two persons to assimilate and develop the expertise to manage vaccine storage and LNVP operations. LN2 for recharging cryoshippers was delivered every 1-2 weeks. Vaccine ordering, receipt, storage and inventory control was conducted effectively. Simulated single dose vaccine cryovial retrieval and thawing were performed successfully in different travel clinic settings. Continuous temperature monitoring at each site was maintained with only one short excursion above -150 °C (-145 °C) through shipping, use and reverse logistics. Staff, during and at study conclusion, provided feedback that has been incorporated into our models for cold chain logistics. CONCLUSIONS: These studies demonstrated that the training in delivery, storage, administration and integration of PfSPZ vaccines can be successfully managed in different immunization clinic settings for travellers and military personnel.


Asunto(s)
Vacunas contra el Virus del Ébola , Fiebre Hemorrágica Ebola , Malaria Falciparum , Medicina Militar , Humanos , Refrigeración , Vacunas contra la COVID-19 , Malaria Falciparum/prevención & control , Plasmodium falciparum
6.
IJID Reg ; 10: 44-51, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38149263

RESUMEN

Objectives: To identify the SARS-CoV-2 variants Delta and Omicron during the fourth wave of the COVID-19 pandemic in Mexico using samples taken from 19 locations in 18 out of the 32 states. Methods: The genetic material concentration was done with PEG/NaCl precipitation, SARS-CoV-2 presence was confirmed by reverse transcriptase-quantitative polymerase chain reaction assay, the variant detection was carried out using a commercial mutation detection panel kit, and variant/mutation confirmation was done by amplicon sequencing of receptor-binding domain target region. The study used 41 samples. Results: The Delta variant was confirmed in two samples during August 2021 (Querétaro and CDMX) and in three samples during November 2021 (Aguascalientes, Ciudad Juárez campuses, and Nuevo Leon). In December 2021, another sample with the Delta variant was confirmed in Nuevo Leon. Between January to March 2022 only the presence of Omicron was confirmed, (variant BA.1). Additionally, in this period six samples were identified with the status "Variant Not Determined". Conclusion: To our knowledge, this study is one of the first to identify Omicron and Delta variants with polymerase chain reaction in Mexico and Latin America and its distribution across the country with 56% Mexican states making it a viable alternative for variant detection without conducting a large quantity of sequencing of clinical tests.

7.
Environ Int ; 184: 108462, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38335627

RESUMEN

While Alzheimer's disease (AD) diagnosis, management, and care have become priorities for healthcare providers and researcher's worldwide due to rapid population aging, epidemiologic surveillance efforts are currently limited by costly, invasive diagnostic procedures, particularly in low to middle income countries (LMIC). In recent years, wastewater-based epidemiology (WBE) has emerged as a promising tool for public health assessment through detection and quantification of specific biomarkers in wastewater, but applications for non-infectious diseases such as AD remain limited. This early review seeks to summarize AD-related biomarkers and urine and other peripheral biofluids and discuss their potential integration to WBE platforms to guide the first prospective efforts in the field. Promising results have been reported in clinical settings, indicating the potential of amyloid ß, tau, neural thread protein, long non-coding RNAs, oxidative stress markers and other dysregulated metabolites for AD diagnosis, but questions regarding their concentration and stability in wastewater and the correlation between clinical levels and sewage circulation must be addressed in future studies before comprehensive WBE systems can be developed.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/epidemiología , Péptidos beta-Amiloides , Monitoreo Epidemiológico Basado en Aguas Residuales , Aguas Residuales , Estudios Prospectivos , Biomarcadores
8.
Biosensors (Basel) ; 13(10)2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37887115

RESUMEN

Food and waterborne illnesses are still a major concern in health and food safety areas. Every year, almost 0.42 million and 2.2 million deaths related to food and waterborne illness are reported worldwide, respectively. In foodborne pathogens, bacteria such as Salmonella, Shiga-toxin producer Escherichia coli, Campylobacter, and Listeria monocytogenes are considered to be high-concern pathogens. High-concern waterborne pathogens are Vibrio cholerae, leptospirosis, Schistosoma mansoni, and Schistosima japonicum, among others. Despite the major efforts of food and water quality control to monitor the presence of these pathogens of concern in these kinds of sources, foodborne and waterborne illness occurrence is still high globally. For these reasons, the development of novel and faster pathogen-detection methods applicable to real-time surveillance strategies are required. Methods based on biosensor devices have emerged as novel tools for faster detection of food and water pathogens, in contrast to traditional methods that are usually time-consuming and are unsuitable for large-scale monitoring. Biosensor devices can be summarized as devices that use biochemical reactions with a biorecognition section (isolated enzymes, antibodies, tissues, genetic materials, or aptamers) to detect pathogens. In most cases, biosensors are based on the correlation of electrical, thermal, or optical signals in the presence of pathogen biomarkers. The application of nano and molecular technologies allows the identification of pathogens in a faster and high-sensibility manner, at extremely low-pathogen concentrations. In fact, the integration of gold, silver, iron, and magnetic nanoparticles (NP) in biosensors has demonstrated an improvement in their detection functionality. The present review summarizes the principal application of nanomaterials and biosensor-based devices for the detection of pathogens in food and water samples. Additionally, it highlights the improvement of biosensor devices through nanomaterials. Nanomaterials offer unique advantages for pathogen detection. The nanoscale and high specific surface area allows for more effective interaction with pathogenic agents, enhancing the sensitivity and selectivity of the biosensors. Finally, biosensors' capability to functionalize with specific molecules such as antibodies or nucleic acids facilitates the specific detection of the target pathogens.


Asunto(s)
Técnicas Biosensibles , Listeria monocytogenes , Nanoestructuras , Microbiología de Alimentos , Técnicas Biosensibles/métodos , Listeria monocytogenes/genética , Escherichia coli
9.
Viruses ; 15(9)2023 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-37766347

RESUMEN

Although wastewater-based surveillance (WBS) is an efficient community-wide surveillance tool, its implementation for pathogen surveillance remains limited by ineffective sample treatment procedures, as the complex composition of wastewater often interferes with biomarker recovery. Moreover, current sampling protocols based on grab samples are susceptible to fluctuant biomarker concentrations and may increase operative costs, often rendering such systems inaccessible to communities in low-to-middle-income countries (LMICs). As a response, passive samplers have emerged as a way to make wastewater sampling more efficient and obtain more reliable, consistent data. Therefore, this study aims to review recent developments in passive sampling technologies to provide researchers with the tools to develop novel passive sampling strategies. Although promising advances in the development of nanostructured passive samplers have been reported, optimization remains a significant area of opportunity for researchers in the area, as methods for flexible, robust adsorption and recovery of viral genetic materials would greatly improve the efficacy of WBS systems while making them more accessible for communities worldwide.


Asunto(s)
Monitoreo Epidemiológico Basado en Aguas Residuales , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Tecnología
10.
Rev Biol Trop ; 60(3): 995-1014, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23025075

RESUMEN

Little evidence exists on the dependence between the presence and abundance of juvenile hermatypic corals and the conditions of their habitats, despite that juveniles contribute with the understanding of the community structure and its reproductive success. To assess this, the abundance of nine species of juvenile corals was correlated with eight macro-habitat (location of the reef on shelf, depth) and micro-habitat (type and inclination of the substrate, exposure to light, texture and amount of sediment accumulated on bottom, potential growth area for juveniles) conditions. Sampling was conducted in four insular coral reefs in the Colombian Caribbean: two oceanic and two continental reefs (influenced by large rivers), covering a total of 600m2 and the distribution of corals on a vertical gradient. Contingency tables and coefficients (magnitude) and multiple correspondence analyses were used to evaluate the dependency ratios for each species. The results showed that Agaricia tenuifolia displayed the most robust pattern of dependence (two high and two moderate), significant for juveniles present at a high frequency in continental reefs, devoid of potential area for juvenile growth (surrounded by macroalgae), and covering horizontal substrates exposed to light. The juveniles were associated with a habitat of moderate to high bottom accumulation of extremely fine sediment. Porites astreoides presented four moderate dependencies; ocean reefs between 2-16m depths, a high frequency of juveniles on horizontal substrates, exposed to light, non-sedimented and occupied by competitors. Siderastrea siderea displayed three moderate dependences for juveniles in cryptic zones, inclined substrate and devoid of competitors. A. lamarcki, Leptoseris cucullata and A. agaricites presented two moderate dependences; these species share high abundance of juveniles in habitats with no sediment, exposed to light and occupied by competitors (except A. agaricites). The P. porites, Favia fragum and Montastraea cavernosa species had a moderate dependence with high incidence of juveniles in ocean reefs and microhabitats exposed to light. For the nine species, results indicate that the presence (colonization), abundance and survival of juveniles, depend on certain species-specific particularities of the habitat. However, the juveniles show high tolerance and plasticity to a range of habitat variables, given their independence and low dependence observed in over 50% of the variables assessed.


Asunto(s)
Antozoos/clasificación , Arrecifes de Coral , Fenómenos Ecológicos y Ambientales , Animales , Región del Caribe , Colombia , Densidad de Población
11.
PLoS One ; 17(4): e0245109, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35385470

RESUMEN

The formulation of effective control strategies for any pest species generally involves the study of habitat use and preference and niche width in anthropogenically transformed natural landscapes. We evaluated whether the use, habitat preference, and niche range of the Amblyomma mixtum tick changed between stages, habitats, and seasonality (dry-wet seasons 2019) on a farm in Yopal (Casanare, Colombia). The presence and relative abundance of free-living larvae, nymphs, and adults was quantified in four different habitats according to the type of vegetation cover (Riparian Forest, Cocoa Crop, King Grass Crop, and Star Grass Paddock). Habitat availability was estimated, environmental variables were analyzed, and various indices of habitat use and preference, and niche width were calculated. A. mixtum's habitat use and preference, and niche width changed between stages, habitat types, and time of the year. The total abundance of A. mixtum was an order of magnitude greater in the dry season than the wet season. In the dry season, all stages used all habitats, while A. mixtum adults used all the habitats in both seasons. In the dry season, nymphs and larvae preferred three out of the four habitats, while adults preferred the King Grass Crop. In the wet season, nymphs and larvae preferred two habitats, whereas the adults preferred the King Grass Crop. The value of the niche width index was high for larvae, nymphs, and adults in the dry season, while it was high only for adults in the wet season. Thus, A. mixtum's vast environmental tolerance and niche breadth allows the species to use and colonize changing habitats (unstable or temporary) with fluctuating environmental conditions (e.g., King Grass Crop), potentially keeping a stable population over time and making it an extremely resistant species. However, the wet flooding season in Yopal may exceed A. mixtum's stages' tolerances.


Asunto(s)
Amblyomma , Ecosistema , Animales , Colombia , Estaciones del Año
12.
BMC Psychol ; 9(1): 127, 2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34452647

RESUMEN

BACKGROUND: Populations exposed to Armed Conflict Experiences (ACE) show different levels of impact in their mental health (i.e. clinical and positive components); however, there is limited evidence related to mental health of general population (civilians not classified as victims) exposed to ACE. Government guided mental health assessments exclude this population. The use of a newly validated Extreme Experiences Scale (EX2) seems appropriate to classify victims, ex-combatants, and civilians for their mental health assessment. METHODS: Here, we propose a novel approach to identify relationships between individuals classified with different levels of ACE exposure-independent of their legal role in the armed conflict, and mental health outcomes. According to the cut-off points derived from the scores of EX2, we classified the sample in low and high exposure to ACE. RESULTS: The high-level ACE group (scores > 2.5) included 119 subjects, and the low-level ACE was constituted by 66 subjects. Our results evidence that people with high exposure to ACE experiment higher odds to present anxiety disorders, risk of suicide, or post-traumatic stress disorder, as well as increased cognitive empathy (i.e., fantasy dimension). CONCLUSION: These findings allowed us to identify the influence of ACE on mental health outcomes beyond the conventional frame (victim or ex-combatant), and to discuss effective interventions and implementation of mental health strategies in these communities. We expect to help the health system to focus on key vulnerable subjects by including civilians not recognized as victims, which are neglected from most of the public health screening, assessment, and interventions.


Asunto(s)
Trastornos por Estrés Postraumático , Trastornos de Ansiedad , Conflictos Armados , Humanos , Salud Mental , Evaluación de Resultado en la Atención de Salud , Trastornos por Estrés Postraumático/epidemiología
13.
Folia Microbiol (Praha) ; 66(5): 843-853, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34170482

RESUMEN

Clostridium perfringens forms biofilms and spores that are a source of food contamination. In this study, the antibacterial activities of Lactobacillus plantarum culture supernatants (LP-S), LP-S fractions, and the plant-derived compound epigallocatechin gallate (EG) were evaluated. Specifically, their effects on the viability and biofilm-forming ability of C. perfringens were assessed. Moreover, the expression of quorum sensing-regulated genes associated with the pathogenesis of this microorganism and that of genes involved in biofilm formation was also investigated. The results showed that both EG and the LP-S exerted bactericidal activity against all C. perfringens strains tested. The minimal bactericidal concentration (MBC) of EG was 75 µg/mL for all strains but ranged from 61 to 121 µg of total protein per mL for LP-S. EG exerted only minor effects on biofilm formation, whereas LP-S, particularly its 10 and 30 K fractions, significantly reduced the biofilm-forming ability of all the strains. The antibiofilm activity of LP-S was lost following preincubation with proteases, suggesting that it was mediated by a proteinaceous molecule. The treatment of C. perfringens with either EG or LP-S did not change the transcript levels of two CpAL (C. perfringens quorum-sensing Agr-like system)-related genes, agrB and agrD, which are known to be involved in the regulation of biofilms, suggesting that LP-S exerted its biofilm inhibitory activity downstream of CpAL signaling. In summary, we demonstrated the bactericidal activity of EG and LP-S against C. perfringens and antibiofilm activity of LP-S at a subinhibitory dose. Our results suggested that these compounds can be further explored for food safety applications to control agents such as C. perfringens.


Asunto(s)
Catequina/análogos & derivados , Clostridium perfringens , Medios de Cultivo Condicionados , Lactobacillus plantarum , Biopelículas , Catequina/farmacología , Clostridium perfringens/efectos de los fármacos , Clostridium perfringens/genética , Medios de Cultivo Condicionados/farmacología , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Lactobacillus plantarum/metabolismo
14.
Psychol Sci ; 21(2): 298-304, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20424060

RESUMEN

Anxiety modulates the functioning of attention. Although the existence of this relationship is clear, its nature is still poorly defined. Added are the facts that different types of anxiety--state or trait--may influence attention differently and that attention is not a unitary system. We studied the influence of such types of anxiety by means of a task that, using emotionally neutral information, assesses the efficiency of three attentional networks: orienting, alerting, and executive control. Results showed a double dissociation. Trait anxiety was related to deficiencies in the executive control network, but state anxiety was associated with an overfunctioning of the alerting and orienting networks.


Asunto(s)
Ansiedad/psicología , Atención , Carácter , Orientación , Reconocimiento Visual de Modelos , Tiempo de Reacción , Adolescente , Adulto , Afecto , Nivel de Alerta , Función Ejecutiva , Femenino , Humanos , Masculino , Inventario de Personalidad , Adulto Joven
15.
Brain Cogn ; 73(3): 222-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20566235

RESUMEN

Temporal preparation and impulsivity involve overlapping neural structures (prefrontal cortex) and cognitive functions (response inhibition and time perception), however, their interrelations had not been investigated. We studied such interrelations by comparing the performance of groups with low vs. high non-clinical trait impulsivity during a temporal preparation go no-go task. This task measured, in less than 10 min, how response inhibition was influenced both by temporal orienting of attention (guided by predictive temporal cues) and by sequential effects (produced by repetition/alternation of the duration of preparatory intervals in consecutive trials). The results showed that sequential effects produced dissociable patterns of temporal preparation as a function of impulsivity. Sequential effects facilitated both response speed (reaction times - RTs - to the go condition) and response inhibition (false alarms to the no-go condition) selectively in the low impulsivity group. In the high impulsivity group, in contrast, sequential effects only improved RTs but not response inhibition. We concluded that both excitatory and inhibitory processing may be enhanced concurrently by sequential effects, which enables the temporal preparation of fast and controlled responses. Impulsivity could hence be related to less efficient temporal preparation of that inhibitory processing.


Asunto(s)
Atención/fisiología , Discriminación en Psicología/fisiología , Conducta Impulsiva , Inhibición Psicológica , Tiempo de Reacción/fisiología , Percepción del Tiempo/fisiología , Adulto , Análisis de Varianza , Femenino , Humanos , Masculino , Orientación/fisiología , Valores de Referencia , Disposición en Psicología , Detección de Señal Psicológica/fisiología , Adulto Joven
16.
PLoS One ; 15(10): e0240545, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33057351

RESUMEN

The bacterial strain, EMM-1, was isolated from the rhizosphere of red maize ("Rojo Criollo") and identified as Pseudomonas protegens EMM-1 based on phylogenetic analysis of 16S rDNA, rpoB, rpoD, and gyrB gene sequences. We uncovered genes involved in the production of antimicrobial compounds like 2,4-diacetylphloroglucinol (2,4-DAPG), pyoluteorin, and lectin-like bacteriocins. These antimicrobial compounds are also produced by other fluorescent pseudomonads alike P. protegens. Double-layer agar assay showed that P. protegens EMM-1 inhibited the growth of several multidrug-resistant (MDR) bacteria, especially clinical isolates of the genera Klebsiella and ß-hemolytic Streptococcus. This strain also displayed inhibitory effects against diverse fungi, such as Aspergillus, Botrytis, and Fusarium. Besides, a crude extract of inhibitory substances secreted into agar was obtained after the cold-leaching process, and physicochemical characterization was performed. The partially purified inhibitory substances produced by P. protegens EMM-1 inhibited the growth of Streptococcus sp. and Microbacterium sp., but no inhibitory effect was noted for other bacterial or fungal strains. The molecular weight determined after ultrafiltration was between 3 and 10 kDa. The inhibitory activity was thermally stable up to 60°C (but completely lost at 100°C), and the inhibitory activity remained active in a wide pH range (from 3 to 9). After treatment with a protease from Bacillus licheniformis, the inhibitory activity was decreased by 90%, suggesting the presence of proteic natural compounds. All these findings suggested that P. protegens EMM-1 is a potential source of antimicrobials to be used against pathogens for humans and plants.


Asunto(s)
Antiinfecciosos/toxicidad , Bacteriocinas/toxicidad , Pseudomonas/metabolismo , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/metabolismo , Antiinfecciosos/uso terapéutico , Antibiosis , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Bacteriocinas/aislamiento & purificación , Bacteriocinas/metabolismo , Bacteriocinas/uso terapéutico , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Micosis/tratamiento farmacológico , Micosis/microbiología , Enfermedades de las Plantas/prevención & control , Rizosfera , Zea mays/microbiología
17.
Rev Biol Trop ; 57(4): 939-54, 2009 Dec.
Artículo en Español | MEDLINE | ID: mdl-20073326

RESUMEN

Currently, Montastraea annularis populations are suffering from high partial mortality rates; yet few studies have determined type, frequency and intensity of natural lesions in situ. During a year we followed natural lesions that appeared on healthy ramets of a population on a degraded reef within a Marine Protected Area in Colombia, to infer the effect on population size structure. From September 2003 to September 2004, 94% of the ramets presented lesions caused by bleaching, predation; or algae, sponge and borrower interactions. Predation caused 47% of the lesions and algae 36%; most lesions (85%) were small (<5cm2), although some were bigger than 60cm2 (0.3%). Lesion recovery was high (83%), but 11.2% did not recover or grow. On 2.5% algae invasion was seen. Bleaching lesions affected more ramet area (>60% of its live tissue) and were evident from September to November, yet total recovery was found in three months. In contrast, lesions by algae (36%), showed less recovery (6.7%), and a tendency to grow in time. In general, percentage of affected tissue area of a ramet in any month was lower than 10%. Nevertheless from May to September, the area affected was larger (10-50%) due to an increase in frequency and abundance of predation, bleaching and algal damage, and a decrease in recovery. At the end of the year, lesions that did not recover caused partial mortality in 25% of the ramets. Ramets with lesions shrunk throughout the year and by the end of year, 21% passed to a smaller class size.


Asunto(s)
Antozoos/fisiología , Regeneración/fisiología , Animales , Colombia , Estaciones del Año
18.
Anim Reprod Sci ; 210: 106197, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31635782

RESUMEN

Cryopreservation in liquid nitrogen (LN2) allows for semen to be stored for long periods of time while there is sustaining of sperm viability. In this study, there was assessment of effects induced by different storage temperatures on cryopreserved dog spermatozoa. After cryopreservation at -196 °C, sperm samples were transferred to storage conditions of -80, 21 or -8 °C. Sperm motility, morphology, viability, acrosome integrity, mitochondrial membrane potential and DNA fragmentation were determined in samples stored at -196 °C (evaluation time =0 h), and then after 12 h and 1, 4, 7 and 15 d of storage at 80, -21 and -8 °C. In samples stored at -80 °C, sperm morphology, viability, acrosome integrity, mitochondrial membrane potential and DNA fragmentation did not differ at successive evaluation times. Progressive motility was less (P < 0.05) after 12 h and total motility after 4 d of storage at -80 ºC as compared with that of the 0 h sample. With storage at the other temperatures (-21 and -8 ºC), there was a reduction of mean values for sperm total and progressive motility, viability and mitochondrial membrane potential after 12 h of storage at these temperatures. Results, therefore, indicate the use of ultra-freezers at -80 ºC to store frozen dog semen allows for maintenance of sperm characteristics for at least 15 d but motility is sustained for only 1 d. Neither of the -21 or -8 ºC storage temperatures were effective for storing of frozen dog sperm and retaining viability.


Asunto(s)
Criopreservación/veterinaria , Perros/fisiología , Congelación , Espermatozoides/fisiología , Animales , Supervivencia Celular , Cromatina , Masculino , Potencial de la Membrana Mitocondrial , Nitrógeno , Motilidad Espermática
19.
Ginecol Obstet Mex ; 76(5): 261-6, 2008 May.
Artículo en Español | MEDLINE | ID: mdl-18798430

RESUMEN

BACKGROUND: In Mexico there isn't accurate epidemiologic information of osteoporosis prevalence, however it is estimated that 24.5 million people are at risk or suffer it yet. OBJECTIVE: To show prevalence of osteoporosis in open population of several areas of Mexico City. PATIENTS AND METHOD: Retrospective, transversal and open study at an osseous densitometric data base information from 5,924 patients. RESULTS: Densitometry evidence that 17.9% suffer osteoporosis (79.8 female and 20.1% male), 34.5% osteopeny (76.1 female and 23.8 female), and 47.4% had normal bones (75.8% female and 24.1% female). CONCLUSIONS: Since osseous mineral density changes exponentially increases with age, osteopenic and osteoporosis index is very high after 40 years old; due to that there must be considered preventative programs for young groups, and to practice densitometries to 30 year old men and women.


Asunto(s)
Osteoporosis/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Población Urbana
20.
Sci Rep ; 8(1): 9354, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29921956

RESUMEN

Long-distance dispersal is believed to strongly influence coral reef population dynamics across the Tropical Pacific. However, the spatial scale and strength at which populations are potentially connected by dispersal remains uncertain. To determine the patterns in connectivity between the Eastern (ETP) and Central Tropical Pacific (CTP) ecoregions, we used a biophysical model incorporating ocean currents and larval biology to quantify the seascape-wide dispersal potential among all population. We quantified the likelihood and determined the oceanographic conditions that enable the dispersal of coral larvae across the Eastern Pacific Barrier (EP-Barrier) and identified the main connectivity pathways and their conservation value for dominant reef-building corals. Overall, we found that coral assemblages within the CTP and ETP are weakly connected through dispersal. Although the EP-Barrier isolates the ETP from the CTP ecoregion, we found evidence that the EP-Barrier may be breached, in both directions, by rare dispersal events. These rare events could explain the evolutionary genetic similarity among populations of pocilloporids in the ecoregions. Moreover, the ETP may function as a stronger source rather than a destination, providing potential recruits to CTP populations. We also show evidence for a connectivity loop in the ETP, which may positively influence long-term population persistence in the region. Coral conservation and management communities should consider eight-key stepping stone ecoregions when developing strategies to preserve the long-distance connectivity potential across the ETP and CTP.


Asunto(s)
Antozoos/crecimiento & desarrollo , Animales , Arrecifes de Coral , Flujo Génico/fisiología , Genética de Población , Geografía , Oceanografía , Dinámica Poblacional
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