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1.
Psychol Med ; 53(9): 4266-4274, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35534479

RESUMEN

BACKGROUND: Patients with anti-N-methyl-d-aspartate (NMDA) receptor encephalitis (ANMDARE) show a wide range of behavioral abnormalities and are often mistaken for primary psychiatric presentations. We aimed to determine the behavioral hallmarks of ANMDARE with the use of systematic neuropsychiatric and cognitive assessments. METHODS: A prospective study was conducted, with 160 patients admitted to the National Institute of Neurology and Neurosurgery of Mexico, who fulfilled criteria for possible autoimmune encephalitis and/or red flags along a time window of seven years. Cerebrospinal fluid (CSF) antibodies against the NR1 subunit of the NMDAR were processed with rat brain immunohistochemistry and cell-based assays with NMDA expressing cells. Systematic cognitive, neuropsychiatric, and functional assessments were conducted before knowing NMDAR antibodies results. A multivariate analysis was used to compare patients with and without definite ANMDARE according to antibodies in CSF. RESULTS: After obtaining the CSF antibodies results in 160 consecutive cases, 100 patients were positive and classified as having definite ANMDARE. The most frequent neuropsychiatric patterns were psychosis (81%), delirium (75%), catatonia (69%), anxiety-depression (65%), and mania (27%). Cognition was significantly impaired. A total of 34% of the patients had a predominantly neuropsychiatric presentation without seizures. After multivariate analysis, the clinical hallmarks of ANMDARE consisted of a catatonia-delirium comorbidity, tonic-clonic seizures, and orolingual dyskinesia. CONCLUSIONS: Our study supports the notion of a neurobehavioral phenotype of ANMDARE characterized by a fluctuating course with psychotic and affective symptoms, catatonic signs, and global cognitive dysfunction, often accompanied by seizures and dyskinesia. The catatonia-delirium comorbidity could be a distinctive neurobehavioral phenotype of ANMDARE.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Catatonia , Delirio , Discinesias , Humanos , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico , Encefalitis Antirreceptor N-Metil-D-Aspartato/líquido cefalorraquídeo , Catatonia/etiología , Estudios Prospectivos , N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Convulsiones/complicaciones , Delirio/complicaciones , Discinesias/complicaciones
2.
Environ Res ; 216(Pt 4): 114772, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36379235

RESUMEN

In this work nanocomposites based on alginate (Alg) and halloysite as a nanotubular clay (Hy) were developed. Characterization techniques reveal that Hy/Alg nanocomposites are cation exchangers with predominantly negative charge density and good thermal stability. The adsorption equilibrium of Cd(II) in aqueous solution onto Hy/Alg nanocomposites revealed that by increasing the mass of halloysite in the nanocomposite, the adsorption capacity diminished significantly due to the halloysite-alginate interactions. Maximum adsorption capacities of 8, 65, 88, and 132 mg/g of Cd(II) were obtained for samples Hy, Hy/Alg 50%, Hy/Alg 95%, and Alg, respectively. In addition, the adsorption equilibrium of Cd(II) on the Hy/Alg bionanocomposites was affected by the pH and temperature of the solution, demonstrating the presence of electrostatic interactions during adsorption and that this is an exothermic process. The controlling mechanism of adsorption was cation exchange influenced by electrostatic forces. The Cd(II) adsorption rate studies were interpreted by the diffusion-permeation model and reveal that the presence of Hy in the structure of the nanocomposites enhances the permeation coefficient, that is, the adsorption rate was increased. The values of the permeation coefficient varied from 1.95 × 10-7 to 8.50 × 10-7 cm2/s for Hy/Alg 50% and from 1.70 × 10-7 to 3.55 × 10-7 cm2/s for Hy/Alg 95%.


Asunto(s)
Alginatos , Nanocompuestos , Arcilla/química , Adsorción , Alginatos/química , Cadmio , Minerales , Cinética , Concentración de Iones de Hidrógeno
3.
Environ Res ; 217: 114852, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36457238

RESUMEN

Metformin consumption for diabetes treatment is increasing, leading to its presence in wastewater treatment plants where conventional methods cannot remove it. Therefore, this work aims to analyze the performance of advanced oxidation processes using sulfate radicals in the degradation of metformin from water. Experiments were performed in a photoreactor provided with a low-pressure Hg lamp, using K2S2O8 as oxidant and varying the initial metformin concentration (CA0), oxidant concentration (Cox), temperature (T), and pH in a response surface experimental design. The degradation percentages ranged from 26.1 to 87.3%, while the mineralization percentages varied between 15.1 and 64%. Analysis of variance (ANOVA) showed that the output variables were more significantly affected by CA0, Cox, and T. Besides, a reduction of CA0 and an increase of Cox up to 5000 µM maximizes the metformin degradation since the generation of radicals and their interaction with metformin molecules are favored. For the greatest degradation percentage, the first order apparent rate constant achieved was 0.084 min-1. Furthermore, while in acidic pH, temperature benefits metformin degradation, an opposite behavior is obtained in a basic medium because of recombination and inhibition reactions. Moreover, three degradation pathways were suggested based on the six products detected by HPLC-MS: N-cyanoguanidine m/z = 85; N,N-dimethylurea m/z = 89; N,N-dimethyl-cyanamide m/z = 71 N,N-dimethyl-formamide m/z = 74; glicolonitrilo m/z = 58; and guanidine m/z = 60. Finally, it was shown that in general the toxicity of the degradation byproducts was lower than the toxicity of metformin toward Chlamydomonas reinhardtii.


Asunto(s)
Metformina , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Oxidantes , Sulfatos/química , Oxidación-Reducción , Agua , Rayos Ultravioleta , Cinética
4.
Environ Res ; 231(Pt 3): 116280, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37257742

RESUMEN

This work presents a one-step synthesis methodology for preparing a hydrochar (HC) doped with TiO2 (HC-TiO2) for its application on the degradation of crystal violet (CV) using UV and visible radiation. Byrsonima crassifolia stones were used as precursors along with TiO2 particles. The HC-TiO2 sample was synthesized at 210 °C for 9 h using autogenous pressure. The photocatalyst was characterized to evaluate the TiO2 dispersion, specific surface area, graphitization degree, and band-gap value. Finally, the degradation of CV was investigated by varying the operating conditions of the system, the reuse of the catalyst, and the degradation mechanism. The physicochemical characterization of the HC-TiO2 composite showed good dispersion of TiO2 in the carbonaceous particle. The presence of TiO2 on the hydrochar surface yields a bandgap value of 1.17 eV, enhancing photocatalyst activation with visible radiation. The degradation results evidenced a synergistic effect with both types of radiation due to the hybridized π electrons in the sp2-hybridized structures in the HC surface. The degradation percentages were on average 20% higher using UV radiation than visible radiation under the following conditions: [CV] = 20 mg/L, 1 g/L of photocatalyst load, and pH = 7.0. The reusability experiments demonstrated the feasibility of reusing the HC-TiO2 material up to 5 times with a similar photodegradation percentage. Finally, the results indicated that the HC-TiO2 composite could be considered an efficient material for the photocatalytic treatment of water contaminated with CV.


Asunto(s)
Violeta de Genciana , Rayos Ultravioleta , Luz , Titanio/química , Catálisis
5.
J Dairy Sci ; 106(1): 187-201, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36357210

RESUMEN

The periparturient period is a metabolically demanding time for dairy animals because of increased nutrient requirements for milk yield. The objective of this study was to investigate the effect of feeding Saccharomyces cerevisiae boulardii (CNCM I-1079), a commercial active dry yeast (ADY), in dairy cows on productive and metabolic measures during the periparturient period. Primiparous (n = 33) and multiparous (n = 35) cows were fed a close-up total mixed ration (TMR) before calving and a lactation TMR postpartum. Three weeks before expected calving time, animals were blocked by parity and body weight and then randomly assigned to either control group (control; n = 34) or treatment (ADY; n = 34). All animals were housed in a tie-stall barn with individual feed bunks; the ADY animals received supplementary Saccharomyces cerevisiae boulardii (CNCM I-1079), top dressed daily at a predicted dosage of 1.0 × 1010 cfu (12.5 g) per head. Blood samples were collected weekly along with milk yield and milk composition data; feed intake data were collected daily. Serum samples were analyzed for glucose, nonesterified fatty acid, ß-hydroxybutyrate, haptoglobin (Hp), and the cytokines tumor necrosis factor-α, IL-6, and IL-18. Colostrum samples collected within the first 6 to 10 h were analyzed for somatic cell score and IgG, IgA, and IgM concentrations. Data were analyzed using PROC GLIMMIX in SAS with time as a repeated measure; model included time, parity, treatment, and their interactions. The ADY groups had greater milk yield (39.0 ± 2.4 vs. 36.7 ± 2.3 kg/d) and tended to produce more energy-corrected milk with better feed efficiency. There was no difference in plasma glucose, serum nonesterified fatty acid, serum ß-hydroxybutyrate, Hp, IL-6, or IL-18 due to ADY treatment. The tumor necrosis factor-α increased in ADY-supplemented animals (1.17 ± 0.69 vs. 4.96 ± 7.7 ng/mL), though week, parity, and their interactions had no effect. Serum amyloid A tended to increase in ADY-supplemented animals when compared to control animals and was additionally affected by week and parity; there were no significant interactions. No difference in colostrum IgG, IgA, and IgM was observed between treatments. Supplementing transition cow TMR with ADY (CNCM I-1079) improved milk production and tended to improve efficiency in early lactation; markers of inflammation were also influenced by ADY treatment, though the immunological effect was inconsistent.


Asunto(s)
Saccharomyces boulardii , Saccharomyces cerevisiae , Embarazo , Femenino , Bovinos , Animales , Saccharomyces cerevisiae/metabolismo , Interleucina-18/metabolismo , Ácido 3-Hidroxibutírico , Factor de Necrosis Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Dieta/veterinaria , Metabolismo Energético , Lactancia , Leche/metabolismo , Ingestión de Alimentos , Periodo Posparto/metabolismo , Ácidos Grasos no Esterificados , Inmunoglobulina A/metabolismo , Inmunoglobulina G/metabolismo , Inmunoglobulina M , Alimentación Animal/análisis
6.
J Environ Manage ; 336: 117664, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36921470

RESUMEN

The increase in energy and fertilizer consumption makes it necessary to develop sustainable alternatives for agriculture. Anaerobic digestion and digestates appeared to be suitable options. However, untreated digestates still have high water content and can increase greenhouse gas emissions during storage and land application. In this study, manure-derived digestate and solid fraction of digestate after separation were treated with a novel solar drying technology to reduce their water content, combined with acidification to reduce the gaseous emissions. The acidified digestate and acidified solid fraction of digestate recovered more nitrogen and ammonia nitrogen than their respective non-acidified products (1.5-1.3 times for TN; 14 times for TAN). Ammonia and methane emissions were reduced up to 94% and 72% respectively, compared to the non-acidified ones, while N2O increased more than 3 times. Dried digestate and dried acidified digestate can be labeled as NPK organic fertilizer regarding the European regulation, and the dried solid fraction and the improved dried acidified solid fraction can be labeled as N or P organic fertilizer. Moreover, plant tests showed that N concentrations in fresh lettuce leaves were within the EU limit with all products in all the cases. However, zinc concentration appeared to be a limitation in some of the products as their concentration exceeded the European legal limits.


Asunto(s)
Amoníaco , Estiércol , Fertilizantes , Agricultura , Nitrógeno/análisis , Concentración de Iones de Hidrógeno , Agua , Anaerobiosis
7.
Mol Phylogenet Evol ; 173: 107515, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35577293

RESUMEN

Rapid speciation is an important aspect of adaptive radiations, but can obfuscate phylogenetic relationships among taxa. For recent radiations, there are challenges to reconstructing the relationships among the species due to often shorter branch lengths. Resolution of these relationships is further confounded when studies only use a few genetic markers. Double digest restriction-site associated DNA sequencing (ddRADseq) is a method of next generation sequencing that identifies many single nucleotide polymorphisms (SNPs) throughout the genome. This increases statistical power to resolve close phylogenetic relationships like those found within an adaptive radiation. We used this approach to understand the evolutionary history of the rockfishes of the genus Sebastes, which experienced an adaptive radiation between 3 and 5 mya. Here, we reconstructed the phylogenetic relationships among six species of rockfish within the subgenus Sebastosomus using over 11,600 SNPs. This reconstruction includes the two recently diverged species, Sebastes mystinus and S. diaconus, that were first described genetically in 2008 using mtDNA control region sequence data and six microsatellite loci. We confirmed the relationship of these cryptic species as sister-taxa and found evidence that S. melanops and S. flavidus were also sister-taxa. The latter contradicts prior studies but is supported by our reconstruction using nuclear DNA and measures of genetic differentiation tests and a discriminant analysis of principal components. The relationships between the species of Sebastosomus are further supported by morphological, biological, and ecological justifications.


Asunto(s)
ADN Mitocondrial , Perciformes , Animales , ADN Mitocondrial/genética , Repeticiones de Microsatélite , Perciformes/genética , Filogenia , Análisis de Secuencia de ADN
8.
Med Vet Entomol ; 35(3): 302-314, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33249628

RESUMEN

Despite the medical importance of sandflies as vectors (Diptera: Phlebotominae) of Leishmania spp., immature stages of phlebotomine sandflies have never been found in the wild in Mexico. In the present investigation, we sought to identify specific microhabitats associated with the presence of sandfly immature stages. Field work was conducted in 11 localities of the Yucatan Peninsula and we collected soil samples from each site during two periods (November 2007 to April 2008, November 2008). Soil samples were transported to our base camp and were processed using the Berlese's funnels. We processed a total 242 soil samples with an average weight of 362 ± (SD) 317 gr. From these samples, we were able to recover 51 phlebotomine larvae in five different microhabitats and largest number was obtained from mammal burrows (88%) and from tree-buttresses of Brosimium alicastrum (Berg) (6%). We identified larval microhabitat for Brumptomyia hamata (Fairchild & Hertig) and those specimens provided the material to describe for the first time the fourth instar larva. We also include information of a larval microhabitat of Lutzomyia cruciata (Coquillett). In addition, we recorded a total of 4872 arthropods from 15 taxa in all those soil samples in which sandfly larvae were found, being Collembola (76%) and Acari (10%) the most abundant.


Asunto(s)
Phlebotomus , Psychodidae , Animales , Insectos Vectores , Larva , México
9.
Med Vet Entomol ; 34(4): 440-451, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32697402

RESUMEN

The Phyllosoma complex is a Triatominae (Hemiptera: Reduviidae) group of medical importance involved in Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) transmission. Most of the members of this group are endemic and sympatric species with distribution in Mexico and the southern U.S.A. We employed MaxEnt to construct ecological niche models of nine species of Triatominae to test three hypothesis: (a) whether species with a broad climatic niche breadth occupy a broader geographical range than species with a narrow climatic breadth, (b) whether species with broad distribution present high degree of climatic fragmentation/isolation, which was tested through landscape metrics; and (c) whether the species share the same climatic niche space (niche conservatism) considered through an equivalence test implemented in ENMtools. Overall, our results suggest that the geographical distribution of this complex is influenced mainly by temperature seasonality where all suitable areas are places of current and potential transmission of T. cruzi. Niche breadth in the Phyllosoma complex is associated with the geographical distribution range, and the geographical range affects the climatic connectivity. We found no strong evidence of niche climatic divergence in members of this complex. We discuss the epidemiological implications of these results.


Asunto(s)
Enfermedad de Chagas/transmisión , Clima , Triatominae , Animales , Ecosistema , Geografía , Insectos Vectores/parasitología , México/epidemiología , Modelos Biológicos , Estaciones del Año , Temperatura , Triatominae/parasitología , Trypanosoma cruzi
10.
Public Health Nutr ; 23(S1): s21-s28, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32157979

RESUMEN

OBJECTIVE: To estimate the prevalence of malnutrition (undernutrition and excess BMI) among children under the age of 5 years and women of reproductive age in Bolivia considering three socioeconomic indicators: wealth, education and ethnicity. DESIGN: We used the 2008 nationally representative Bolivian Demographic and Health Survey (DHS). Malnutrition's prevalence was estimated by wealth, ethnicity and educational level. Wealth index was measured based on the DHS methodology and nutritional status by using WHO standards and indicators. Education level (EL) was categorized by years of formal education. SETTING: Bolivia. PARTICIPANTS: In total, 5·903 children <5 years, 3·345 adolescent women (15-19 years) and 12·297 women (20-49 years) with available information on anthropometric measurements·. RESULTS: A disproportionate prevalence of malnutrition was observed among different wealth groups: lower wealth tertiles show the higher prevalence of stunting (>30 %) and anaemia (>40 %) in all ages· The prevalence of overweight and obesity tends to rise with age from childhood (10·02-11·60) to adolescence (27·9-31·03), reaching highest levels in women of reproductive age (56·02-57·76). According to wealth tertiles, higher prevalence of overweight and obesity was found in children of high tertile (12·23), adolescent women of low (32·56) and adult women of medium tertile (63·08). CONCLUSIONS: The present study shows that currently Bolivia is in a transitional stage, faces not only the problem of undernutrition but also those of overnutrition, showing strong inequalities according to socioeconomic and education status. This study calls for state-specific policies keeping in view of the nature of inequality in malnutrition in the country and its differential characteristics across wealth status.


Asunto(s)
Escolaridad , Etnicidad/estadística & datos numéricos , Desnutrición/epidemiología , Factores Socioeconómicos , Adolescente , Adulto , Anemia/epidemiología , Índice de Masa Corporal , Bolivia/epidemiología , Preescolar , Factores Económicos , Femenino , Trastornos del Crecimiento/epidemiología , Encuestas Epidemiológicas , Humanos , Masculino , Desnutrición/etnología , Persona de Mediana Edad , Estado Nutricional , Obesidad/epidemiología , Sobrepeso/epidemiología , Prevalencia , Clase Social , Adulto Joven
11.
Herz ; 45(6): 586-593, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30276479

RESUMEN

BACKGROUND: The aim of our study was to assess the outcomes of surgical treatment for severe tricuspid regurgitation according to whether cardiac surgery had been performed before the tricuspid valve intervention. METHODS: Between 1996 and 2013, 201 consecutive patients with severe tricuspid regurgitation underwent tricuspid surgery at our center. Patients were classified according to whether or not they had undergone previous cardiac surgery, which 33% of the sample had. Perioperative as well as long-term morbidity and mortality were analyzed. RESULTS: Mean patient age was 62.3 years. 32.8% underwent suture annuloplasty, 41.3% underwent ring annuloplasty, 15.4% received a bioprosthesis, and 10.4% received a mechanical prosthesis. There were no significant differences in perioperative mortality between the group that had not undergone previous cardiac surgery and the group that had (12.7% vs. 17.9%, respectively; p = 0.32). The long-term mortality rate (median follow-up time: 53 months) was 43.3%. Long-term survival curves showed no significant differences between the two groups (p = 0.884), and previous cardiac surgery was not a predictive factor for long-term mortality (hazard ratio = 1.211; p = 0.521). CONCLUSION: In a series of patients who underwent tricuspid valve surgery, no significant differences were observed in perioperative mortality or in long-term survival according to whether or not subjects had undergone previous cardiac surgery.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Anuloplastia de la Válvula Cardíaca , Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Tricúspide , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Válvula Tricúspide/diagnóstico por imagen , Válvula Tricúspide/cirugía , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/cirugía
12.
Public Health ; 172: 52-60, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31202092

RESUMEN

OBJECTIVE: In Ecuador, the reported maternal death rate was 45.71 per 100,000 live births in 2013. This may be partly due to a lack of maternal knowledge of obstetric warning signs during pregnancy, delivery and the post-partum period. This study sought to evaluate awareness of obstetric warning signs among pregnant women in relation to individual demographic and area-level socio-economic indicators. STUDY DESIGN: We conducted a cross-sectional analysis of data collected by Ecuador's Ministry of Health at the conclusion of a national maternal health campaign (2014-2015). A nationally representative sample of 3435 pregnant women from the nine administrative zones completed surveys regarding basic demographics and their awareness of obstetric warning signs. METHODS: We defined eight obstetrical warning signs according to the literature and Ecuadorian practice that could occur during pregnancy, delivery and the post-partum period (severe headache, strong abdominal ache, bleeding or presence of malodorous secretion, rupture of the amniotic sac, high fever, abnormal presentation of the baby, decrease in baby's movements and delayed labour). A woman was considered 'aware' if she recognised at least four of the eight warning signs and stated she would seek immediate healthcare at their presentation. For each administrative zone, four socio-economic indicators (poverty, illiteracy, unemployment and subemployment) were obtained from the National Institute of Statistics and Census. Correlates of awareness of the obstetric warning signs were evaluated using hierarchical logistic models clustered by the administrative zone. RESULTS: Nationally, 86.9% of women were 'aware' of obstetric warning signs. After adjustment for age, socio-economic indicators and clustering, indigenous participants were 59% less likely to be aware of obstetric warning signs than mestizos (odds ratio [OR] = 0.41, 95% confidence interval [CI] = 0.28-0.59). For every 1% increase in area poverty, participants had a 5% decreased likelihood of being aware of obstetric warning signs (OR = 0.95, 95% CI = 0.93-0.96), adjusting for age, ethnicity and other socio-economic indicators. The most effective source of campaign information about obstetric warning signs was personal communication with a healthcare professional, as opposed to mass media advertisements (OR = 1.90, 95% CI = 1.34-2.71). CONCLUSIONS: A majority of Ecuadorian pregnant and post-partum women are aware of obstetric warning signs. Indigenous ethnicity and area-level poverty are associated with a lack of awareness. Personal communication with a healthcare professional was the most effective source of information. These findings have implications for improvement of maternal awareness of warning signs.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Complicaciones del Trabajo de Parto/psicología , Adulto , Estudios Transversales , Ecuador/epidemiología , Femenino , Conocimientos, Actitudes y Práctica en Salud/etnología , Humanos , Mortalidad Materna , Grupos de Población/psicología , Grupos de Población/estadística & datos numéricos , Áreas de Pobreza , Embarazo , Encuestas y Cuestionarios , Adulto Joven
14.
Phys Chem Chem Phys ; 20(9): 6198-6210, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-29431772

RESUMEN

Cyclopropyl cyanide and other simple nitriles detected in Titan's atmosphere could be precursors leading to the formation of organic macromolecules in the atmosphere of Saturn's largest satellite. Proposing a thermodynamically possible mechanism that explains their formation and supports experimental results represents a difficult challenge. Experiments done in the Atomic and Molecular Physics Laboratory at the University of Trento (AMPL) have studied the ion-molecule reaction between cyclopropyl cyanide and its protonated form, with reaction products being characterized by mass spectrometry. In addition to the expected ion-molecule adduct stabilized by non-covalent long-range interactions, in this work we prove that another distinct species having the same mass to charge ratio (m/z) of 135 is also produced. Moreover, from a previous study of the neutral cyclopropyl cyanide potential energy surface (PES) which shows a partial biradical character it has been possible to characterize the formation through the bimolecular reaction of a new covalent cyclic organic molecule. Calculations have been carried out at the ab initio Møller-Plesset (MP2) level of theory, ensuring the connectivity of the stationary points by using the intrinsic reaction coordinate (IRC) procedure. In order to characterize the reaction transition state, multireference calculations were done using a complete active space involving six electrons and six molecular orbitals [CAS (6 e-, 6 m.o.)]. This study opens the possibility of exploring the formation of new organic molecules by gaseous phase ion-molecule interaction schemes, with such molecules having relevance in interstellar space and in astrobiology (and may be involved in prebiotic molecular evolution).

15.
Med Vet Entomol ; 32(4): 443-450, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29969158

RESUMEN

The Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae), is a highly invasive species and a vector of several viruses of serious concern to public health. Investigating the habitat selection of this species at small to medium scales is essential to the planning of effective prevention and control campaigns. The present group considered detailed data for this species' presence/absence collected at 228 sites on Mallorca Island (Spain) in autumn 2015, 3 years after the first detection of the species on the island. Site occupancy models accounting for false negative detections and imperfect monitoring were used to evaluate the relationships between mosquito presence and habitat variables. In the study area, mosquito presence was negatively associated with altitude, probably as a result of greater human presence at low altitudes near the coast. Moreover, the presence of Ae. albopictus was positively associated with swimming pools as a result of associated gardens, plants and sources of fresh water. These two variables were combined to predict the presence of the species across the entire island.


Asunto(s)
Aedes/fisiología , Actividades Humanas , Animales , Ecosistema , Islas del Mediterráneo , Modelos Biológicos , Probabilidad , España , Viaje , Agua
16.
Ecology ; 98(8): 2170-2179, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28547863

RESUMEN

The number of nesting leatherback turtles (Dermochelys coriacea) in the eastern Pacific Ocean has declined dramatically since the late 1980s. This decline has been attributed to egg poaching and interactions with fisheries. However, it is not clear how much of the decline should also be ascribed to variability in the physical characteristics of the ocean. We used data on individually marked turtles that nest at Playa Grande, Costa Rica, to address whether climatic variability affects survival and inter-breeding interval. Because some turtles might nest undetected, we used capture-recapture models to model survival probability accounting for a detection failure. In addition, as the probability of reproduction is constrained by past nesting events, we formulated a new parameterization to estimate inter-breeding intervals and contrast hypotheses on the role of climatic covariates on reproductive frequency. Average annual survival for the period 1993-2011 was low (0.78) and varied over time ranging from 0.49 to 0.99 with a negative temporal trend mainly due to the high mortality values registered after 2004. Survival probability was not associated with the Multivariate ENSO Index of the South Pacific Ocean (MEI) but this index explained 24% of the temporal variability in the reproductive frequency. The probability of a turtle to permanently leave after the first encounter was 26%. This high proportion of transients might be associated with a high mortality cost of the first reproduction or with a long-distance nesting dispersal after the first nesting season. Although current data do not allow separating these two hypotheses, low encounter rate at other locations and high investment in reproduction, supports the first hypothesis. The low and variable annual survival probability has largely contributed to the decline of this leatherback population. The lack of correlation between survival probability and the most important climatic driver of oceanic processes in the Pacific discards a climate-related decline and point to anthropogenic sources of mortality as the main causes responsible for the observed population decline.


Asunto(s)
Monitoreo del Ambiente , Tortugas/fisiología , Animales , Costa Rica , Explotaciones Pesqueras , Comportamiento de Nidificación , Océanos y Mares , Océano Pacífico
17.
Phys Chem Chem Phys ; 19(2): 1181-1189, 2017 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-27942644

RESUMEN

A comprehensive study of the self-assembly in water of a lipopeptide consisting of a sequence of l-proline, l-arginine and l-tryptophan with a hydrocarbon chain has been performed. Fluorescence assays were used to determine the critical aggregation concentration. In situ small-angle X-ray scattering (SAXS) and molecular dynamics simulations showed the presence of spherical micelles with diameters around 6 nm. In agreement with these results, cryo-TEM images showed globular aggregates with diameters ranging from ≈4 nm up to ≈9 nm. Furthermore, the lipopeptide catalytic activity has been tested for the direct aldol reaction between cyclohexanone and p-nitrobenzaldehyde, and we have observed that the self-association of the organocatalyst played a critical role in the enhanced activity. Water affects the selectivity, and poor results are obtained under neat reaction conditions. The location of the catalytic groups at the lipopetide/water solvent interface also endowed unusual selectivity in the catalyzed aldol reactions. Under optimized reaction conditions, high yields (up to >99%), good enantioselectivity (ee up to 85%) and high diastereoselectivity (ds up to 92 : 8) were obtained.


Asunto(s)
Lipopéptidos/química , Micelas , Aldehídos/química , Arginina/química , Benzaldehídos/química , Catálisis , Microscopía por Crioelectrón , Ciclohexanonas/química , Lipopéptidos/síntesis química , Lipopéptidos/ultraestructura , Simulación de Dinámica Molecular , Prolina/química , Dispersión del Ángulo Pequeño , Triptófano/química , Agua/química , Difracción de Rayos X
18.
J Chem Phys ; 146(13): 134301, 2017 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-28390361

RESUMEN

Gas phase reactive collisions between lithium ions and i-C3H7X (X = Br, OH) molecules have been studied under single collision conditions in the center of mass (CM) 0.01-10.00 eV energy range using a radiofrequency-guided ion beam apparatus. Mass spectrometry analysis of the products did show the presence of [C3H6-Li]+, [HX-Li]+, C3H7+, and C2H3+ as well as of the [Li-i-C3H7Br]+ adduct while [Li-i-C3H7OH]+ was hardly detected. For all these reactive processes, the corresponding cross sections have been measured in absolute units as a function of the CM collision energy. Quantum chemistry ab initio calculations done at the second order Möller Plesset level have provided relevant information on the topology of the potential energy surfaces (PESs) where a reaction takes place allowing the characterization of the stationary points on the respective PESs along their reaction pathways. The connectivity of the different stationary points localized on the PESs was ensured by using the intrinsic reaction coordinate (IRC) method, confirming the adiabatic character of the reactions. The main topology features of the reactive PESs, in the absence of dynamical calculations, were used to interpret at the qualitative level the behavior of the experimental excitations functions, evidencing the role played by the potential energy barriers on the experimental dynamics of the reactions. Reaction rate constants at 303.2 K for different reactions have been calculated from measured excitation functions.

19.
Med Vet Entomol ; 31(1): 63-71, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27753118

RESUMEN

Little is known about how the virulence of a human pathogen varies in the environment it shares with its vector. This study focused on whether the virulence of Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae), the causal agent of Chagas' disease, is related to altitude. Accordingly, Triatoma dimidiata (Hemiptera: Reduviidae) specimens were collected at three different altitudes (300, 700 and 1400 m a.s.l.) in Chiapas, Mexico. The parasite was then isolated to infect uninfected T. dimidiata from the same altitudes, as well as female CD-1 mice. The response variables were phenoloxidase (PO) activity, a key insect immune response, parasitaemia in mice, and amastigote numbers in the heart, oesophagus, gastrocnemius and brain of the rodents. The highest levels of PO activity, parasitaemia and amastigotes were found for Tryp. cruzi isolates sourced from 700 m a.s.l., particularly in the mouse brain. A polymerase chain reaction-based analysis indicated that all Tryp. cruzi isolates belonged to a Tryp. cruzi I lineage. Thus, Tryp. cruzi from 700 m a.s.l. may be more dangerous than sources at other altitudes. At this altitude, T. dimidiata is more common, apparently because the conditions are more beneficial to its development. Control strategies should focus activity at altitudes around 700 m a.s.l., at least in relation to the region of the present study sites.


Asunto(s)
Altitud , Inmunidad Innata , Triatoma/inmunología , Triatoma/parasitología , Trypanosoma cruzi/parasitología , Animales , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/parasitología , Femenino , Insectos Vectores/inmunología , Insectos Vectores/parasitología , México , Ratones , Trypanosoma cruzi/patogenicidad , Trypanosoma cruzi/fisiología , Virulencia
20.
Drug Dev Res ; 78(2): 105-115, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28345130

RESUMEN

Preclinical Research The aim of this study was to determine the antiallodynic effect of acute administration of the ß-lactam antimicrobials, ceftriaxone (CFX) and clavulanic acid (CLAV), for the control of established pain on a model of neuropathic pain (NP). We also investigated the involvement of dopaminergic and opioidergic pathways as well as alterations in serum concentrations of TNF-α in the antiallodynic actions of these drugs. CFX, CLAV, or gabapentin (GAP), a reference drug, were administered i.p. twelve days after constriction of the sciatic nerve in rats. Mechanic and cold allodynia were evaluated for 3 h and alterations in serum concentration of TNF-α determined. Both CFX and CLAV had antiallodynic effects in response to mechanical and cold stimulation, similar to GAP. The antiallodynic effects of CFX and CLAV were blocked by haloperidol (HAL), a D2 receptor antagonist, and by naloxone (NLX), an opioid receptor antagonist. Additionally, serum TNF-α levels were attenuated following CFX and CLAV administration. These results suggest that acute administration of CFX and CLAV may represent a promising approach for treating the acute allodynia of NP, and that the mechanisms involved in these effects involve activation of dopaminergic and opioidergic pathways as well as modulation of TNF-α production. Drug Dev Res 78 : 105-115, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Ceftriaxona/administración & dosificación , Ácido Clavulánico/administración & dosificación , Hiperalgesia/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/sangre , Animales , Ceftriaxona/farmacología , Ácido Clavulánico/farmacología , Frío , Antagonistas de Dopamina/administración & dosificación , Regulación de la Expresión Génica/efectos de los fármacos , Haloperidol/administración & dosificación , Hiperalgesia/sangre , Hiperalgesia/etiología , Inyecciones Intraperitoneales , Masculino , Naloxona/administración & dosificación , Antagonistas de Narcóticos/administración & dosificación , Ratas , Tacto
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