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1.
Environ Res ; 239(Pt 1): 117281, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37827370

RESUMEN

Lanthanides are indispensable constituents of modern technologies and are often challenging to acquire from natural resources. The demand for REEs is so high that there is a clear need to develop efficient and eco-friendly recycling methods. In the present study, freeze-dried biomass of the polyextremophile Galdieria sulphuraria was employed to recover REEs from spent fluorescent lamps (FL) luminophores by pretreating the freeze-dried biomass with an acid solution to favour ion exchange and enhance the binding sites on the cell surface available for the metal ions. Lanthanides were extracted from the luminophores using sulfuric acid solutions according to standardised procedures, and the effect of biosorbent dosage (0.5-5 mg/ml) and biosorption time (5-60 min) were evaluated. The content of individual REEs in the luminophores and the resulting algal biomass were determined using inductively coupled plasma mass spectrometry (ICP-MS). The most abundant REE in the luminophores was yttrium (287.42 mg/g dm, 91.60% of all REEs), followed by europium (20.98 mg/g, 6.69%); cerium, gadolinium, terbium and lanthanum was in trace. The best biosorption performances were achieved after 5 min and at the lowest biosorbent dosage (0.5 mg/mL). The highest total metal amount corresponded to 41.61 mg/g dried mass, and yttrium was the most adsorbed metal (34.59 mg/g dm, 82.88%), followed by cerium (4.01 mg/g); all other metals were less than 2 mg/g. The rapidity of the biosorption process and the low biosorbent dosage required confirmed this microalga as a promising material for creating an eco-sustainable protocol for recycling REEs.


Asunto(s)
Cerio , Metales de Tierras Raras , Rhodophyta , Metales de Tierras Raras/análisis , Itrio , Metales/metabolismo , Rhodophyta/metabolismo
2.
Chemosphere ; 317: 137818, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36640971

RESUMEN

The recovering of trivalent Lanthanides from aqueous solutions, by biosorption process onto Galdieria sulphuraria lifeless cells, was investigated. Potentiometry, UV-Vis, FTIR-ATR spectroscopy and SEM-EDS analysis were used. All the experiments were performed at 25 °C, in 0.5 M NaCl. Ln3+ biosorption is greater in the 5-6 pH range with values ranging from 80 µmol/g to 130 µmol/g (dry weight). The adsorbed Ln3+ ions can be recovered at higher acidity (pH<1) and the biosorbent can be reused. Specific molecular interactions between Ln3+ ions and the functional groups on G. sulphuraria surface were highlighted. Particularly, proteins are involved if Ln3+=Pr3+, Sm3+, Eu3+, Tb3+, Dy3+, Tm3+, while Ce3+, Ho3+, Er3+ form bonds with carbohydrates. Finally, both proteins and carbohydrates are involved if Gd3+ and Yb3+. A Surface Complexation approach, with a good graphical fitting to potentiometric experimental collected data, was used to describe the biosorption mechanism. This study could be of great applicative utility for removing of trivalent actinides, from waste aqueous solutions, by biosorption. As well known the lanthanides were used as model to simulate the chemical behaviour of actinides in the same oxidation state.


Asunto(s)
Elementos de Series Actinoides , Elementos de la Serie de los Lantanoides , Rhodophyta , Elementos de la Serie de los Lantanoides/química , Iones
3.
Atlanta; Current Developments in Nutrition; 20220200. 10 p. Tab. (PCI-271).
No convencional en Inglés | REPincaP, LIGCSA | ID: biblio-1397396

RESUMEN

Practice-based experiences documenting development and implementation of nutrition and health surveillance systems are needed. To describe processes, methods, and lessons learned from developing and implementing a population-based household nutrition and health surveillance system in Guatemala. The phases and methods for the design and implementation of the surveillance system are described. Efforts to institutionalize the system in government institutions are described, and illustrative examples describing different data uses, and lessons learned are provided. After initial assessments of data needs and consultations with officials in government institutions and partners in the country, a population-based nutrition surveillance system prototype with complex sampling was designed and tested in 5 Guatemalan Highland departments in 2011. After dissemination of the prototype, government and partners expanded the content, and multitopic nutrition and health surveillance cycles were collected in 2013, 2015, 2016, 2017/18, and 2018/19 providing nationally representative data for households, women of reproductive age (15­49 y), and children aged 0­59 mo. For each cycle, data were to be collected from 100 clusters, 30 households in each, and 1 woman and 1 child per household. Content covered ∼25 health and nutrition topics, including coverage of all large-scale nutrition-specific Interventions; the micronutrient content of fortifiable sugar, salt, and bread samples; anthropometry; and biomarkers to assess annually, or at least once, ∼25 indicators of micronutrient status and chronic disease. Data were collected by 3­5 highly trained field teams. The design was flexible and revised each cycle allowing potential changes to questionnaires, population groups, biomarkers, survey design, or other changes. Data were used to change national guidelines for vitamin A and B-12 interventions, among others, and evaluate interventions. Barriers included frequent changes of high-level government officials and heavy dependence on US funding. This system provides high-quality data, fills critical data gaps, and can serve as a useful model for others.


Asunto(s)
Vigilancia Sanitaria , Antropometría , Micronutrientes , Grupos de Población , Sistema de Vigilancia Sanitaria
4.
Mult Scler Relat Disord ; 27: 344-349, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30472414

RESUMEN

BACKGROUNG: Multiple sclerosis (MS) results in a broad range of symptoms, including motor, visual, cognitive, and neuropsychiatric deficits. Some studies, considering affective facial expressions to study emotion processing, demonstrated emotion recognition difficulties in MS patients. OBJECTIVE: We investigated the impact of MS on the emotional-behaviour rating and neurophysiological response (Event Related Potentials-ERP) through a battery of affective visual stimuli selected from the International Affective Picture System (IAPS). METHODS: Twenty patients with diagnosis of Relapsing Remitting MS (RRMS) and 20 Healthy Controls (HC) matched by age, gender and education were enrolled. Each of them, after a neuropsychological assessment, were asked to evaluate arousal and valence of affective visual stimuli. RESULTS: Our results showed higher P300 amplitudes in RRMS patients than HC group for pleasant and unpleasant images. Moreover, RRMS patients showed lower Reaction Time (RT) respect HC in valence rating. No other effect did emerge between groups. CONCLUSION: Our study shows early compensatory cerebral mechanisms in RRMS patients throughout emotional information processing, particularly for unpleasant and pleasant stimuli. We hypothesize that this compensatory cerebral mechanism reduces the behavioural dissimilarity between patients and HC.


Asunto(s)
Afecto , Corteza Cerebral/fisiopatología , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Esclerosis Múltiple Recurrente-Remitente/psicología , Adulto , Electroencefalografía , Potenciales Relacionados con Evento P300 , Potenciales Evocados Visuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estimulación Luminosa , Tiempo de Reacción , Percepción Visual/fisiología
5.
Behav Neurol ; 2017: 7404289, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28912625

RESUMEN

Cognitive dysfunction affects 40-65% of multiple sclerosis (MS) patients and can occur in the early stages of the disease. This study aimed to explore cognitive functions by means of the Italian version of the minimal assessment of cognitive function in MS (MACFIMS) in relapsing-remitting MS (RRMS) patients with very mild clinical disability to identify the primarily involved cognitive functions. Ninety-two consecutive RRMS patients with Expanded Disability Status Scale (EDSS) scores ≤ 2.5 and forty-two healthy controls (HC) were investigated. Our results show that 51.1% of MS patients have cognitive dysfunction compared to HC. An impairment of verbal and visual memory, working memory, and executive functions was found in the RRMS group. After subgrouping RRMS by EDSS, group 1 (EDSS ≤ 1.5) showed involvement of verbal memory and executive functions; moreover, group 2 (2 ≤ EDSS ≤ 2.5) patients were also impaired in information processing speed and visual memory. Our results show that utilizing a comprehensive neuropsychological assessment, approximately half of MS patients with very mild physical disability exhibit cognitive impairment with a primary involvement of prefrontal cognitive functions. Detecting impairment of executive functions at an early clinical stage of disease could be useful to promptly enroll MS patients in targeted rehabilitation.


Asunto(s)
Cognición/fisiología , Disfunción Cognitiva/complicaciones , Función Ejecutiva/fisiología , Memoria a Corto Plazo/fisiología , Esclerosis Múltiple Recurrente-Remitente/complicaciones , Adulto , Disfunción Cognitiva/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Esclerosis Múltiple Recurrente-Remitente/psicología , Pruebas Neuropsicológicas , Índice de Severidad de la Enfermedad
6.
Mol Ecol ; 26(16): 4116-4130, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28437594

RESUMEN

Knowledge on the structure and distribution of genetic diversity is a key aspect to plan and execute an efficient conservation and utilization of the genetic resources of any crop as well as for determining historical demographic inferences. In this work, a large data set of 1,765 accessions of cherimoya (Annona cherimola Mill, Annonaceae), an underutilized fruit tree crop native to the Neotropics and used as a food source by pre-Columbian cultures, was collected from six different countries across the American continent and amplified with nine highly informative microsatellite markers. The structure analyses, fine representation of the genetic diversity and an ABC approach suggest a Mesoamerican origin of the crop, contrary to previous reports, with clear implications for the dispersion of plant germplasm between Central and South America in pre-Columbian times. These results together with the potential distribution of the species in a climatic change context using two different climate models provide new insights for the history and conservation of extant genetic resources of cherimoya that can be applied to other currently underutilized woody perennial crops.


Asunto(s)
Annona/genética , Conservación de los Recursos Naturales , Variación Genética , Genética de Población , América Central , Evolución Molecular , Frutas , Repeticiones de Microsatélite , América del Sur , Árboles
7.
New Microbes New Infect ; 11: 45-6, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27257492

RESUMEN

Paenibacillus spp. are bacteria present in the environment but are rarely isolated in humans. Here we report the first case of bone infection caused by Paenibacillus turicensis and a second case of human infection caused by this bacterium.

8.
J Appl Microbiol ; 117(4): 1168-80, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25066530

RESUMEN

AIMS: To investigate low molecular weight compounds produced in vitro by Lysobacter capsici AZ78 and their toxic activity against sporangia of plant pathogenic oomycetes. METHODS AND RESULTS: Assays carried out in vitro showed that L. capsici AZ78 drastically inhibits the growth of plant pathogenic oomycetes. Accordingly, the preventive application of culture filtrates of L. capsici AZ78 on grapevine and tomato plants reduced the infections, respectively, caused by Plasmopara (Pl.) viticola and Phytophthora infestans. The subsequent chemical analysis of the culture filtrates of L. capsici AZ78 by spectroscopic (essentially 1D and 2D (1)H NMR and (13)C NMR and ESI MS spectra) and optical methods led to the identification of the 2,5-diketopiperazine cyclo(L-Pro-L-Tyr) that inhibited the development of P. infestans sporangia in vitro and on tomato leaves. Furthermore, a genomic region with high sequence identity with genes coding for a hybrid polyketide synthase and nonribosomal peptide synthetase was detected in L. capsici AZ78. CONCLUSIONS: Lysobacter capsici AZ78 produces cyclo(L-Pro-L-Tyr) in vitro that was effective in killing the sporangia of P. infestans and Pl. viticola in vitro. Moreover, this low molecular weight compound prevents the occurrence of late blight lesions when applied on tomato leaves. SIGNIFICANCE AND IMPACT OF THE STUDY: The application of L. capsici AZ78 cells or its own culture filtrates effectively controls both P. infestans and Pl. viticola. Cyclo(L-Pro-L-Tyr) produced by L. capsici AZ78 is toxic against sporangia of both these oomycetes. These data enforce the potential in the use of Lysobacter members for the control of plant pathogenic oomycetes and provide the basis for the development of new low-impact fungicides based on cyclo(L-Pro-L-Tyr).


Asunto(s)
Fungicidas Industriales/farmacología , Lysobacter/química , Oomicetos/efectos de los fármacos , Phytophthora infestans/efectos de los fármacos , Enfermedades de las Plantas , Solanum lycopersicum , Lysobacter/genética , Lysobacter/metabolismo , Oomicetos/crecimiento & desarrollo , Péptidos Cíclicos/metabolismo , Piperazinas/metabolismo , Sintasas Poliquetidas/metabolismo , Esporangios/efectos de los fármacos
9.
Acta odontol. venez ; 52(3)2014. ilus, tab, graf
Artículo en Español | LILACS | ID: lil-778009

RESUMEN

Se evaluó la eficacia del hueso liofilizado humano (Matriz Ósea UNC en Polvo) injertado en cavidades alveolares post-extracción, recubierto por una lámina ósea cortical (Matriz Ósea UNC en membrana), en el tratamiento de preservación del perfil volumétrico del reborde alveolar.La metodología de trabajo se fundamentó en: 1) El estudio de una casuística de 27 casos clínicos en pacientes de ambos sexos que poseían elementos dentarios unirradiculares con indicación de extracción. Se injertó en las cavidades óseas resultantes hueso liofilizado, contenido in situ mediante una lámina ósea cortical parcialmente desmineralizada. Los pacientes fueron evaluados clínica y radiográficamente, mediante modelos de estudio, Rx convencional y radiovisiografía que permitieron mensurar las modificaciones producidas por resorción durante un año. Se realizaron controles pre y post-operatorios, a los 7, 15, 30, 60, 90, 120, 180 y 360 días. A los modelos de yeso preliminares y a los obtenidos a los 120 y 360 días se les efectuaron cortes transversales en las zonas de estudio y se los escaneó. Las imágenes obtenidas se procesaron mediante un analizador de imágenes (Image Pro-Plus). Los datos se analizaron estadísticamente con software específico (SPSS). El estudio demostró que las mayores modificaciones dimensionales del reborde se observaron sobre el área superficial del alvéolo y en los primeros 4 meses post-extracción. La lámina cortical presentó características físicas, estructurales y biológicas que le permitieron actuar como barrera física oclusiva, minimizando los fenómenos de inhibición celular heterotípica y favoreciendo los procesos osteogénicos por el mecanismo de osteopromoción...


Human efficacy lyophilized bone (UNC Bone Matrix Powder) grafted post-extraction alveolar sacs, covered by a cortical bone plate (UNC Bone Matrix membrane), in the treatment volume preservation ridge profile was evaluated. The working methodology was based on: 1) The study of a case series of 27 clinical cases in patients of both sexes who had single-rooted tooth elements indicating extraction. It was grafted bone cavities in the resulting lyophilized bone content in situ by a partially demineralized cortical bone plate. Patients were evaluated clinically and radiographically, using study models, and conventional Rx radiovisiography that allowed mensurar resorption induced changes for a year. Pre and post-operative controls at 7, 15, 30, 60, 90, 120, 180 and 360 days were performed. A preliminary plaster models and those obtained at 120 and 360 days transects were conducted in the study areas and were scanned. The images obtained were processed by an image analyzer (Image Pro-Plus). The data were statistically analyzed with software (SPSS) .The study showed that older flange dimensional changes were observed on the surface area of the alveoli and in the first 4 months post-extraction. The cortical sheet submitted physical, structural, and biological characteristics that allowed him to act as occlusive physical barrier, minimizing heterotypic cellular inhibition phenomena and processes favoring osteogenic mechanism osteopromoción...


Asunto(s)
Humanos , Masculino , Aloinjertos , Alveolo Dental/anatomía & histología , Alveolo Dental/lesiones , Extracción Dental/métodos , Liofilización/métodos , Regeneración Ósea , Procedimientos Quirúrgicos Orales , Cirugía Bucal
10.
Anal Bioanal Chem ; 405(19): 6365-71, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23722889

RESUMEN

We report the development of an indirect ELISA procedure for specific identification of chicken-egg yolk and animal glues in painting micro-samples. The results presented integrate previously published work on ELISA recognition of bovine ß-casein and chicken ovalbumin in painting materials. The integrated final ELISA procedure-optimised for protein extraction, immuno-reagent concentrations, blocking solution, incubation time, and temperature-enables multiplex identification, in single samples, of proteinaceous materials, i.e. chicken-egg yolk and albumen, animal glues, and bovine milk and/or casein, mainly used by painters in the past. The procedure has been systematically tested on laboratory models of mural and easel paintings, both naturally and artificially aged, to assess possible inhibitory effects on the immuno-reaction caused by inorganic painting materials (pigments and substrates) and by protein degradation resulting from aging processes. Real samples from case studies, which had previously been investigated and characterised by spectroscopy and chromatography, were successfully studied by use of the developed ELISA procedure. The commercial availability of all the immuno-reagents used, the affordable analytical equipment, and the specificity, sensitivity, and rapidity of ELISA make this method very attractive to diagnostic laboratories in the field of cultural heritage science. Possible further developments to the analytical potential of this technique include improvement of antibody performance and inclusion of other classes of bio-molecules as analytical targets.


Asunto(s)
Adhesivos/análisis , Colorantes/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Pintura/análisis , Animales , Caseínas/análisis , Bovinos , Pollos , Yema de Huevo/química , Ovalbúmina/análisis , Pinturas
11.
Cell Death Dis ; 4: e664, 2013 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-23764845

RESUMEN

The anti-tumoral effects of cannabinoids have been described in different tumor systems, including pancreatic adenocarcinoma, but their mechanism of action remains unclear. We used cannabinoids specific for the CB1 (ACPA) and CB2 (GW) receptors and metabolomic analyses to unravel the potential pathways mediating cannabinoid-dependent inhibition of pancreatic cancer cell growth. Panc1 cells treated with cannabinoids show elevated AMPK activation induced by a ROS-dependent increase of AMP/ATP ratio. ROS promote nuclear translocation of GAPDH, which is further amplified by AMPK, thereby attenuating glycolysis. Furthermore, ROS determine the accumulation of NADH, suggestive of a blockage in the respiratory chain, which in turn inhibits the Krebs cycle. Concomitantly, inhibition of Akt/c-Myc pathway leads to decreased activity of both the pyruvate kinase isoform M2 (PKM2), further downregulating glycolysis, and glutamine uptake. Altogether, these alterations of pancreatic cancer cell metabolism mediated by cannabinoids result in a strong induction of autophagy and in the inhibition of cell growth.


Asunto(s)
Adenilato Quinasa/metabolismo , Antineoplásicos/farmacología , Ácidos Araquidónicos/farmacología , Autofagia , Cannabinoides/farmacología , Indoles/farmacología , Morfolinas/farmacología , Acetilcisteína/farmacología , Adenocarcinoma , Adenosina Monofosfato/metabolismo , Adenosina Trifosfato/metabolismo , Línea Celular Tumoral , Núcleo Celular/enzimología , Ciclo del Ácido Cítrico/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Metabolismo Energético , Activación Enzimática , Glutamina/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/metabolismo , Glucólisis/efectos de los fármacos , Humanos , Neoplasias Pancreáticas , Especies Reactivas de Oxígeno/metabolismo , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB2/agonistas
12.
Cell Death Dis ; 2: e152, 2011 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21525939

RESUMEN

Gemcitabine (GEM, 2',2'-difluorodeoxycytidine) is currently used in advanced pancreatic adenocarcinoma, with a response rate of < 20%. The purpose of our work was to improve GEM activity by addition of cannabinoids. Here, we show that GEM induces both cannabinoid receptor-1 (CB1) and cannabinoid receptor-2 (CB2) receptors by an NF-κB-dependent mechanism and that its association with cannabinoids synergistically inhibits pancreatic adenocarcinoma cell growth and increases reactive oxygen species (ROS) induced by single treatments. The antiproliferative synergism is prevented by the radical scavenger N-acetyl-L-cysteine and by the specific NF-κB inhibitor BAY 11-7085, demonstrating that the induction of ROS by GEM/cannabinoids and of NF-κB by GEM is required for this effect. In addition, we report that neither apoptotic nor cytostatic mechanisms are responsible for the synergistic cell growth inhibition, which is strictly associated with the enhancement of endoplasmic reticulum stress and autophagic cell death. Noteworthy, the antiproliferative synergism is stronger in GEM-resistant pancreatic cancer cell lines compared with GEM-sensitive pancreatic cancer cell lines. The combined treatment strongly inhibits growth of human pancreatic tumor cells xenografted in nude mice without apparent toxic effects. These findings support a key role of the ROS-dependent activation of an autophagic program in the synergistic growth inhibition induced by GEM/cannabinoid combination in human pancreatic cancer cells.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Autofagia/efectos de los fármacos , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/metabolismo , Animales , Cannabinoides/administración & dosificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Sinergismo Farmacológico , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/patología , Femenino , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Pancreáticas/tratamiento farmacológico , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/genética , Receptor Cannabinoide CB2/metabolismo , Estrés Fisiológico , Transcripción Genética/efectos de los fármacos , Trasplante Heterólogo , Gemcitabina
13.
Anal Bioanal Chem ; 399(9): 3011-23, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21170522

RESUMEN

Enzyme-linked immunosorbent assay (ELISA) analysis of proteins offers a particularly promising approach for investigations in cultural heritage on account of its appreciated properties of being highly specific, sensitive, relatively fast, and cost-affordable with respect to other conventional techniques. In spite of that, it has never been fully exploited for routine analyses of painting materials in consideration of several analytical issues that inhibited its diffusion in conservation science: limited sample dimensions, decrease of binder solubility and reduced availability of antibody bonding sites occurring with protein degradation. In this study, an ELISA analytical protocol suited for the identification of aged denatured proteins in ancient painting micro-samples has been developed. We focused on the detection of bovine ß-casein and chicken ovalbumin as markers of bovine milk (or casein) and chicken albumen, respectively. A systematic experimentation of the ELISA protocol has been carried out on mock-ups of mural and easel painting prepared with 13 different pigments to assess limits and strengths of the method when applied for the identification of proteins in presence of a predominant inorganic matrix. The analytical procedure has been optimized with respect to protein extraction, antibodies' concentrations, incubation time and temperature; it allows the detection of the investigated proteins with sensitivity down to nanograms. The optimized protocol was then tested on artificially aged painting models. Analytical results were very encouraging and demonstrated that ELISA allows for protein analysis also in degraded painting samples. To address the feasibility of the developed ELISA methodology, we positively investigated real painting samples and results have been cross-validated by gas chromatography-mass spectrometry.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática/métodos , Pintura/análisis , Pinturas , Proteínas/análisis , Animales , Caseínas/análisis , Bovinos , Pollos , Clara de Huevo/análisis
15.
Arch Virol ; 155(6): 857-69, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20376682

RESUMEN

Tomatoes in Guatemala have been affected by a new disease, locally known as "mancha de chocolate" (chocolate spot). The disease is characterized by distinct necrotic spots on leaves, stems and petioles that eventually expand and cause a dieback of apical tissues. Samples from symptomatic plants tested negative for infection by tomato spotted wilt virus, tobacco streak virus, tobacco etch virus and other known tomato-infecting viruses. A virus-like agent was sap-transmitted from diseased tissue to Nicotiana benthamiana and, when graft-transmitted to tomato, this agent induced chocolate spot symptoms. This virus-like agent also was sap-transmitted to Datura stramonium and Nicotiana glutinosa, but not to a range of non-solanaceous indicator plants. Icosahedral virions approximately 28-30 nm in diameter were purified from symptomatic N. benthamiana plants. When rub-inoculated onto leaves of N. benthamiana plants, these virions induced symptoms indistinguishable from those in N. benthamiana plants infected with the sap-transmissible virus associated with chocolate spot disease. Tomatoes inoculated with sap or grafted with shoots from N. benthamiana plants infected with purified virions developed typical chocolate spot symptoms, consistent with this virus being the causal agent of the disease. Analysis of nucleic acids associated with purified virions of the chocolate-spot-associated virus, revealed a genome composed of two single-stranded RNAs of approximately 7.5 and approximately 5.1 kb. Sequence analysis of these RNAs revealed a genome organization similar to recently described torradoviruses, a new group of picorna-like viruses causing necrosis-associated diseases of tomatoes in Europe [tomato torrado virus (ToTV)] and Mexico [tomato apex necrosis virus (ToANV) and tomato marchitez virus (ToMarV)]. Thus, the approximately 7.5 kb and approximately 5.1 kb RNAs of the chocolate-spot-associated virus corresponded to the torradovirus RNA1 and RNA2, respectively; however, sequence comparisons revealed 64-83% identities with RNA1 and RNA2 sequences of ToTV, ToANV and ToMarV. Together, these results indicate that the chocolate-spot-associated virus is a member of a distinct torradovirus species and, thus, another member of the recently established genus Torradovirus in the family Secoviridae. The name tomato chocolate spot virus is proposed.


Asunto(s)
Picornaviridae/clasificación , Picornaviridae/patogenicidad , Enfermedades de las Plantas/virología , Solanum lycopersicum/virología , Guatemala , Microscopía Electrónica , Datos de Secuencia Molecular , Picornaviridae/genética , Picornaviridae/aislamiento & purificación , Hojas de la Planta/virología , Análisis de Secuencia de ADN , Especificidad de la Especie , Nicotiana/virología , Virión/clasificación , Virión/genética , Virión/aislamiento & purificación , Virión/patogenicidad
16.
Plant Physiol ; 152(3): 1514-28, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20089767

RESUMEN

Mitochondria play an essential role in nitric oxide (NO) signal transduction in plants. Using the biotin-switch method in conjunction with nano-liquid chromatography and mass spectrometry, we identified 11 candidate proteins that were S-nitrosylated and/or glutathionylated in mitochondria of Arabidopsis (Arabidopsis thaliana) leaves. These included glycine decarboxylase complex (GDC), a key enzyme of the photorespiratory C(2) cycle in C3 plants. GDC activity was inhibited by S-nitrosoglutathione due to S-nitrosylation/S-glutathionylation of several cysteine residues. Gas-exchange measurements demonstrated that the bacterial elicitor harpin, a strong inducer of reactive oxygen species and NO, inhibits GDC activity. Furthermore, an inhibitor of GDC, aminoacetonitrile, was able to mimic mitochondrial depolarization, hydrogen peroxide production, and cell death in response to stress or harpin treatment of cultured Arabidopsis cells. These findings indicate that the mitochondrial photorespiratory system is involved in the regulation of NO signal transduction in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Glicina-Deshidrogenasa (Descarboxilante)/metabolismo , Mitocondrias/metabolismo , Transducción de Señal , Proteínas de Arabidopsis/aislamiento & purificación , Proteínas de la Membrana Bacteriana Externa/metabolismo , Potencial de la Membrana Mitocondrial , Proteínas Mitocondriales/aislamiento & purificación , Proteínas Mitocondriales/metabolismo , Óxido Nítrico/metabolismo , Proteómica , Especies Reactivas de Oxígeno/metabolismo , S-Nitrosoglutatión/farmacología , Espectrometría de Masas en Tándem
17.
Plant Dis ; 94(4): 482, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30754504

RESUMEN

In Guatemala and other Central American countries, whitefly-transmitted geminiviruses (begomoviruses) cause economically important diseases of tomato (Solanum lycopersicum) and pepper (Capsicum annuum). Disease symptoms include stunted and distorted growth and leaf curling, crumpling, light green to yellow mosaic, purpling, and vein swelling. In Guatemala, at least eight bipartite begomovirus species infect tomato or peppers (1), but their role and relative importance is unclear. As part of an Integrated Pest Management strategy to manage these diseases, surveys for begomovirus symptoms in pepper and tomato have been conducted in the Salama Valley, Sanarate, and other locations since 2003, and begomoviruses were identified by squash blot hybridization, PCR and DNA sequencing. Beginning in 2006, a new type of symptom, stunted upright growth and upcurled leaves with yellowing of the margins and interveinal areas, was observed in tomato and tomatillo plants in the Salama Valley and Sanarate. These symptoms were similar to those induced by the exotic monopartite begomovirus Tomato yellow leaf curl virus (TYLCV). Evidence that TYLCV caused these symptoms came from positive results in high stringency squash blot hybridization tests with a TYLCV probe, and amplification of the expected size of ~0.3- and 2.8-kb fragments in PCR tests with TYLCV capsid protein (CP) gene and full-length component primer pairs, respectively (3). Sequence analyses of PCR-amplified CP fragments and portions of full-length fragments revealed 97 to 99% identity with isolates of TYLCV-Israel (TYLCV-IL). The complete nucleotide sequence of an isolate from the Salama Valley (GenBank Accession No. GU355941) was >99% identical to those of TYLCV-IL isolates from the Dominican Republic, Florida, and Cuba and ~97% identical to those of isolates from Mexico and California. Thus, this TYLCV-IL isolate (TYLCV-IL[GT:06]) was probably introduced from the Caribbean Region. To further characterize begomoviruses in the Salama Valley, leaf samples were collected from 44 and 118 tomato plants showing symptoms of begomovirus infection in March 2006 and 2007, respectively, and from 106 symptomatic pepper plants in March 2007. Begomovirus infection was confirmed in 42 of 44 and 93 of 118 of the tomato samples and 100 of 106 of the pepper samples based on PCR amplification of the expected size of ~0.6- and 1.1-kb DNA fragments with the begomovirus degenerate primers pairs AV494/AC1048 and PAL1v1978/PAR1c496, respectively (2,4). Sequence analyses of cloned PCR-amplified fragments revealed that 3 of the 44 and 16 of the 118 tomato samples collected in 2006 and 2007, respectively, and 9 of the 106 pepper samples were infected with TYLCV based on >97% identity with TYLCV-IL. In all samples, TYLCV was present in mixed infections with other begomoviruses. The introduction of TYLCV adds to the already high level of genetic complexity of bipartite begomovirus infection of tomatoes and peppers in Guatemala and will undoubtedly complicate disease management efforts. References: (1) M. K. Nakhla et al. Acta Hortic. 695:277, 2005. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993. (3) R. Salati et al. Phytopathology 92:487, 2002. (4) S. D. Wyatt and J. Brown. Phytopathology 86:1288, 1996.

18.
Appl Radiat Isot ; 67(10): 1769-74, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19525118

RESUMEN

In recent years, specially designed patches containing beta emitters have been developed for contact brachytherapy of skin lesions. The aim of the present work was to evaluate the biological effects of the (32)P-patch on the skin of Sencar mice as a result of a brachytherapy treatment. For this purpose, a (32)P-patch was prepared with Chromic (32)P-phosphate and silicone and the classical model of two-stage skin carcinogenesis was reproduced in Sencar mice. Animals were divided in six groups. Four groups received the contact brachytherapy treatments using a scheme of a single session of 40 and 60Gy (SD40 and SD60) and a scheme of two sessions of 40 and 60Gy each (FD40 and FD60). The other two groups were used as controls of the single (CSD) and the fractionated (CFD) treatments. Radiation doses were estimated with equations derived from the MIRD DOSE scheme, and biologically effective doses (BED) were calculated according to equations derived from the linear-quadratic model. The endpoint to evaluate the treatments effects was tumor size after a follow-up period of 44 days. Finally, animals were sacrificed in order to get samples of all tumors for histological analysis and PCNA staining. Erythema, dermatitis and skin ulceration developed in almost all treated animals, but they gradually healed with regeneration of tissue during the follow-up period. Radiation effects on the skin of SD40, SD60, FD40 and FD60 showed a significant reduction of the tumor size with regard to controls, independently of the scheme and the radiation dose considered. PCNA staining scores of control groups were higher than for treated groups, independently of the scheme and the radiation dose considered. This radioactive (32)P-silicone-patch which is easy to prepare and use in the treatment of skin diseases, seems promising as a radioactive device for clinical use.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Fósforo/uso terapéutico , Neoplasias Cutáneas/radioterapia , Piel/efectos de la radiación , Administración Cutánea , Animales , Femenino , Ratones , Ratones Endogámicos SENCAR , Antígeno Nuclear de Célula en Proliferación/metabolismo , Dosificación Radioterapéutica , Neoplasias Cutáneas/metabolismo
19.
Eur J Neurol ; 16(11): 1185-90, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19538216

RESUMEN

BACKGROUND AND PURPOSE: It has been proposed that white matter alterations might play a role in autistic disorders; however, published data are mainly limited to high-functioning autism. The goal of this study was to apply diffusion tensor imaging (DTI) and fiber tractography (FT) to study white matter in low-functioning autism and the relationship between white matter and cognitive impairment. METHODS: Ten low-functioning males with autism (mean age: 19.7 +/- 2.83 years) and 10 age-matched healthy males (mean age: 19.9 +/- 2.64 years) underwent DTI-MRI scanning. fractional anisotropy (FA) maps were analyzed with whole brain voxel-wise and tract-of-interest statistics. Using FT algorithms, white matter tracts connecting the orbitofrontal cortex (OFC) with other brain regions were identified and compared between the two groups. FA mean values of the autistic group were correlated with intelligence quotient (IQ) scores. RESULTS: Low-functioning autistic subjects showed a reduced tract volume and lower mean FA values in the left OFC network compared with controls. In the autistic group, lower FA values were associated with lower IQ scores. CONCLUSIONS: We showed evidence of OFC white matter network abnormalities in low-functioning autistic individuals. Our results point to a relationship between the severity of the intellectual impairment and the extent of white matter alterations.


Asunto(s)
Trastorno Autístico/patología , Encéfalo/patología , Discapacidad Intelectual/patología , Fibras Nerviosas Mielínicas/patología , Adolescente , Adulto , Algoritmos , Anisotropía , Mapeo Encefálico , Imagen de Difusión Tensora , Humanos , Procesamiento de Imagen Asistido por Computador , Pruebas de Inteligencia , Masculino , Vías Nerviosas/patología , Pruebas Neuropsicológicas , Estadísticas no Paramétricas
20.
Public Health Nutr ; 12(6): 842-8, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18775084

RESUMEN

OBJECTIVE: To study prospectively the association of coffee intake with incident diabetes in the Puerto Rico Heart Health Program cohort, comprising 9824 middle-aged men (aged 35-79 years). METHODS: Of 9824 men, 3869 did not provide a fasting blood sample at baseline, 1095 had prevalent diabetes and 131 were not given fasting glucose tests at any subsequent study visit. Thus, the present analysis includes 4685 participants. Diabetes was ascertained at baseline and at two study visits between 1968 and 1975 using fasting glucose tests and self-reports of physician-diagnosed diabetes or use of insulin or hypoglycaemic medication. Logistic regression analysis was used to assess the association of coffee intake with risk of incident diabetes while adjusting for covariates (age, BMI, physical activity, smoking, education, alcohol intake, family history of diabetes, intakes of milk and sugar). RESULTS: Five hundred and nineteen participants met the criteria for incident diabetes. Compared with those reporting intake of 1-2 servings of coffee/d, coffee abstainers were at reduced risk (OR = 0.64; 95 % CI 0.43, 0.94). Among coffee drinkers, there was a significant trend of decreasing risk by intake (P = 0.02); intake of >/=4 servings/d was associated with an odds ratio of 0.75 (95 % CI 0.58, 0.97). CONCLUSIONS: Study findings support a protective effect of coffee intake on diabetes risk, while also suggesting that abstainers may be at reduced risk.


Asunto(s)
Café , Diabetes Mellitus Tipo 2/epidemiología , Medición de Riesgo , Adulto , Anciano , Glucemia/análisis , Índice de Masa Corporal , Estudios de Cohortes , Diabetes Mellitus Tipo 2/prevención & control , Ingestión de Líquidos , Prueba de Tolerancia a la Glucosa , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Prospectivos , Puerto Rico/epidemiología
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