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1.
J Biol Chem ; 294(50): 19279-19291, 2019 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-31676688

RESUMEN

The D2 dopamine receptor and the serotonin 5-hydroxytryptamine 2A receptor (5-HT2A) are closely-related G-protein-coupled receptors (GPCRs) from the class A bioamine subfamily. Despite structural similarity, they respond to distinct ligands through distinct downstream pathways, whose dysregulation is linked to depression, bipolar disorder, addiction, and psychosis. They are important drug targets, and it is important to understand how their bias toward G-protein versus ß-arrestin signaling pathways is regulated. Previously, evolution-based computational approaches, difference Evolutionary Trace and Evolutionary Trace-Mutual information (ET-Mip), revealed residues and residue pairs that, when switched in the D2 receptor to the corresponding residues from 5-HT2A, altered ligand potency and G-protein activation efficiency. We have tested these residue swaps for their ability to trigger recruitment of ß-arrestin2 in response to dopamine or serotonin. The results reveal that the selected residues modulate agonist potency, maximal efficacy, and constitutive activity of ß-arrestin2 recruitment. Whereas dopamine potency for most variants was similar to that for WT and lower than for G-protein activation, potency in ß-arrestin2 recruitment for N124H3.42 was more than 5-fold higher. T205M5.54 displayed high constitutive activity, enhanced dopamine potency, and enhanced efficacy in ß-arrestin2 recruitment relative to WT, and L379F6.41 was virtually inactive. These striking differences from WT activity were largely reversed by a compensating mutation (T205M5.54/L379F6.41) at residues previously identified by ET-Mip as functionally coupled. The observation that the signs and relative magnitudes of the effects of mutations in several cases are at odds with their effects on G-protein activation suggests that they also modulate signaling bias.


Asunto(s)
Receptores de Dopamina D2/genética , Transducción de Señal/genética , Células Cultivadas , Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/metabolismo , Serotonina/farmacología , Transducción de Señal/efectos de los fármacos
2.
Environ Microbiol ; 21(5): 1718-1739, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30839140

RESUMEN

Sinorhizobium fredii HH103 RifR , a broad-host-range rhizobial strain, forms ineffective nodules with Lotus japonicus but induces nitrogen-fixing nodules in Lotus burttii roots that are infected by intercellular entry. Here we show that HH103 RifR nolR or nodD2 mutants gain the ability to induce infection thread formation and to form nitrogen-fixing nodules in L. japonicus Gifu. Microscopy studies showed that the mode of infection of L. burttii roots by the nodD2 and nolR mutants switched from intercellular entry to infection threads (ITs). In the presence of the isoflavone genistein, both mutants overproduced Nod-factors. Transcriptomic analyses showed that, in the presence of Lotus japonicus Gifu root exudates, genes related to Nod factors production were overexpressed in both mutants in comparison to HH103 RifR . Complementation of the nodD2 and nolR mutants provoked a decrease in Nod-factor production, the incapacity to form nitrogen-fixing nodules with L. japonicus Gifu and restored the intercellular way of infection in L. burttii. Thus, the capacity of S. fredii HH103 RifR nodD2 and nolR mutants to infect L. burttii and L. japonicus Gifu by ITs and fix nitrogen L. japonicus Gifu might be correlated with Nod-factor overproduction, although other bacterial symbiotic signals could also be involved.


Asunto(s)
Lotus/microbiología , Enfermedades de las Plantas/microbiología , Sinorhizobium fredii/fisiología , Especificidad del Huésped , Mutación , Raíces de Plantas/microbiología , Sinorhizobium fredii/genética , Sinorhizobium fredii/aislamiento & purificación
3.
Hisp J Behav Sci ; 34(4): 525-538, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25104874

RESUMEN

In this study, we investigate individual-level language shift in a population of Mexican origin Latinos/as aged 65 and up. By using data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly, we investigate their English language use as the dependent variable in a hierarchical linear model. The microlevel independent continuous variable is their level of contact with "Anglos"; the macrolevel continuous independent variable is the percentage of Mexicans in tract of residence. After accounting for their generational status, other microlevel social and health covariates, and tract-level attributes, we found a direct relationship between contact with Anglos and a "shift" toward more English language use, where as co-ethnic concentration increases, the influence of contact with Anglos decreases. We frame this article with a discussion on language shifting, and explain how co-ethnic concentration may provide the resources for engaging in a language resistance.

4.
Trends Endocrinol Metab ; 32(6): 403-414, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33838976

RESUMEN

Epidermal growth factor receptor (EGFR) signaling has a central role in the regenerative response of the liver upon injury and is involved in cellular transformation linked to chronic damage. Hepatic EGFR expression, trafficking, and signaling are regulated by growth hormone (GH). Chronically elevated GH levels are associated with liver cancer development and progression in mice. Studies in different in vivo experimental models indicate that EGF and GH mutually crossregulate in a complex manner. Several factors, such as the extent of exposure to supraphysiological GH levels and the pattern of GH administration, are important variables to be considered in exploring the interplay between the two hormones in connection with the progression of hepatic tumors.


Asunto(s)
Factor de Crecimiento Epidérmico , Receptores ErbB , Hormona del Crecimiento , Hígado , Animales , Factor de Crecimiento Epidérmico/fisiología , Receptores ErbB/fisiología , Ratones
5.
Sci Adv ; 7(13)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33771867

RESUMEN

Running waters contribute substantially to global carbon fluxes through decomposition of terrestrial plant litter by aquatic microorganisms and detritivores. Diversity of this litter may influence instream decomposition globally in ways that are not yet understood. We investigated latitudinal differences in decomposition of litter mixtures of low and high functional diversity in 40 streams on 6 continents and spanning 113° of latitude. Despite important variability in our dataset, we found latitudinal differences in the effect of litter functional diversity on decomposition, which we explained as evolutionary adaptations of litter-consuming detritivores to resource availability. Specifically, a balanced diet effect appears to operate at lower latitudes versus a resource concentration effect at higher latitudes. The latitudinal pattern indicates that loss of plant functional diversity will have different consequences on carbon fluxes across the globe, with greater repercussions likely at low latitudes.

6.
Nat Commun ; 12(1): 3700, 2021 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-34140471

RESUMEN

The relationship between detritivore diversity and decomposition can provide information on how biogeochemical cycles are affected by ongoing rates of extinction, but such evidence has come mostly from local studies and microcosm experiments. We conducted a globally distributed experiment (38 streams across 23 countries in 6 continents) using standardised methods to test the hypothesis that detritivore diversity enhances litter decomposition in streams, to establish the role of other characteristics of detritivore assemblages (abundance, biomass and body size), and to determine how patterns vary across realms, biomes and climates. We observed a positive relationship between diversity and decomposition, strongest in tropical areas, and a key role of abundance and biomass at higher latitudes. Our results suggest that litter decomposition might be altered by detritivore extinctions, particularly in tropical areas, where detritivore diversity is already relatively low and some environmental stressors particularly prevalent.


Asunto(s)
Biota , Ecosistema , Ríos , Animales , Biodiversidad , Biomasa , Tamaño Corporal , Chironomidae/fisiología , Clima , Ephemeroptera/fisiología , Insectos/fisiología , Hojas de la Planta/química , Bosque Lluvioso , Ríos/química , Ríos/microbiología , Ríos/parasitología , Ríos/virología , Clima Tropical , Tundra
7.
BMC Res Notes ; 12(1): 119, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30832720

RESUMEN

OBJECTIVE: This exploratory study assessed the safety of the combination of sulfamethoxazole, trimethoprim and guaifenesin (STG) in adult and pediatric patients with acute bronchitis according to local labelling in Peru. RESULTS: We enrolled 51 pediatric and 52 adult participants diagnosed with acute bronchitis and indication of STG. The mean ages were 7.6 years (SD ± 3.2 years) and 42.8 years (SD ± 16.1) and the proportion of female patients were 51% and 65%, respectively. The duration of treatment in pediatric patients was < 5 days in 2% of patients, 5 days in 13.7%, 6-7 days, in 82.4% and > 7 days in 2% while in adults patients it was < 5 days in 17%, 5 days in 69.2%; 6-7 days in 28.8% of patients. Adverse events (AEs) were registered in 9.6% and 19.2% of pediatric and adult patients, respectively. These AEs had definite relation of causality with the study drugs in 2 adults (20% of AEs) and possible causality with the study drugs in 4 pediatric (80% of AEs) and 2 adult cases (20% of AEs). Our results provide valuable data to develop trials of pharmacovigilance where different statistical parameters should be considered to calculate an adequate sample size in studies evaluating STG in pediatric or adult patients. Trial registration NCT02879981 and NCT02902640.


Asunto(s)
Antiinfecciosos/efectos adversos , Bronquitis/tratamiento farmacológico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Expectorantes/efectos adversos , Guaifenesina/efectos adversos , Sulfametoxazol/efectos adversos , Trimetoprim/efectos adversos , Enfermedad Aguda , Adulto , Niño , Preescolar , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Perú , Proyectos Piloto , Resultado del Tratamiento
8.
Mol Clin Oncol ; 6(4): 503-509, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28413656

RESUMEN

Breast cancer (BC) is a heterogeneous disease composed of four main subtypes with distinct clinical and epidemiological features. Although several reports have described the distribution of BC subtypes in Latin America, the majority of them have not included the cellular marker, Ki-67, in the immunohistochemical (IHC) panel. The aim of the present study was to describe the distribution of BC subtypes in a cohort of Latin American women using an IHC panel with Ki-67. A prospective cohort of 580 patients in three centers of Peru (the Hospital Nacional Edgardo Rebagliatti Martins, the Hospital Nacional Guillermo Almenara Irigoyen, the Hospital Nacional Alberto Sabogal, Lima) and one in Uruguay (Instituto Nacional del Cáncer, Montevideo) were evaluated. BC phenotypes were classified according to an IHC panel: Estrogen receptor (ER), progesterone receptor (PgR), HER2 and Ki-67. Silver in situ hybridization was used when the HER2 status, as determined by IHC, was equivocal. The associations between the BC phenotypes and their clinicopathological features were evaluated. ER was positive in 65% of the cases (n=377), and PgR in 50% (n=203). In total, 79.1% (n=459) were HER2-negative, 19.8% (n=115) were HER2-positive and 1% (n=6) had an equivocal status. With respect to Ki-67, 44.7% of the patients exhibited staining in >14% of the tumor cells (n=259). The distribution of subtypes was as follows: Luminal A, 31.9% (n=183); luminal B, 35% (n=201); HER2, 12.1% (n=70); and triple-negative, 20.9% (n=120). When Ki-67 was not included in the panel, the frequency of luminal A was 41.1% and luminal B, 25.8% (9.2% of the cases were misclassified). Ki-67 was most highly expressed in triple-negative and HER2 tumors. Inclusion of Ki-67 in the IHC panel to assign subtypes revealed a higher frequency of luminal B tumors than was reported previously for Latin American women with BC, whereas the distribution of triple-negative and HER2 tumors were similar to that previously reported. In conclusion, these results demonstrated that excluding Ki-67 from the panel of IHC markers may lead to an underestimation of the rates of luminal B tumors.

9.
J Mol Endocrinol ; 54(2): 171-84, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25691498

RESUMEN

GH/STAT5 signaling is desensitized in the liver in adult transgenic mice overexpressing GH; however, these animals present greater body size. To assess whether the STAT5 pathway is active during the growth period in the liver in these animals, and how signaling modulators participate in this process, growing transgenic mice and normal siblings were evaluated. STAT5 does not respond to an acute GH-stimulus, but displays higher basal phosphorylation in the livers of growing GH-overexpressing mice. GH receptor and the positive modulators glucocorticoid receptor and HNF1 display greater abundance in transgenic animals, supporting the activity of STAT5. The negative modulators cytokine-induced suppressor and PTP1B are increased in GH-overexpressing mice. The suppressors SOCS2 and SOCS3 exhibit higher mRNA levels in transgenic mice but lower protein content, indicating that they are being actively degraded. Therefore, STAT5 signaling is increased in the liver in GH-transgenic mice during the growth period, with a balance between positive and negative effectors resulting in accelerated but controlled growth.


Asunto(s)
Hormona del Crecimiento/metabolismo , Hígado/crecimiento & desarrollo , Hígado/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal , Animales , Regulación del Desarrollo de la Expresión Génica , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Fosforilación , Receptores de Somatotropina/genética , Receptores de Somatotropina/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteínas Supresoras de la Señalización de Citocinas/metabolismo
10.
J Endocrinol ; 221(2): 309-23, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24623798

RESUMEN

Current GH administration protocols imply frequent s.c. injections, resulting in suboptimal compliance. Therefore, there is interest in developing delivery systems for sustained release of the hormone. However, GH has different actions depending on its continuous or pulsatile plasma concentration pattern. GH levels and circulating concentration patterns could be involved in the regulation of epidermal growth factor receptor (EGFR) expression in liver. Aberrant expression of this receptor and/or its hyperactivation has been associated with the pathogenesis of different types of carcinoma. Considering that one of the adverse effects associated with GH overexpression and chronic use of GH is the increased incidence of malignancies, the aim of this study was to analyze the effects of GH plasma concentration patterns on EGFR expression and signaling in livers of mice. For this purpose, GH was administered by s.c. daily injections to produce an intermittent plasma pattern or by osmotic pumps to provoke a continuously elevated GH concentration. Intermittent injections of GH induced upregulation of liver EGFR content, augmented the response to EGF, and the induction of proteins involved in promotion of cell proliferation in female mice. In contrast, continuous GH delivery in male mice was associated with diminished EGFR in liver and decreased EGF-induced signaling and expression of early genes. The results indicate that sustained delivery systems that allow continuous GH plasma patterns would be beneficial in terms of treatment safety with regard to the actions of GH on EGFR signaling and its promitogenic activity.


Asunto(s)
Factor de Crecimiento Epidérmico/metabolismo , Hormona del Crecimiento/administración & dosificación , Animales , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Esquema de Medicación , Receptores ErbB/genética , Receptores ErbB/metabolismo , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Hormona del Crecimiento/sangre , Bombas de Infusión , Inyecciones , Masculino , Ratones , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
12.
Rev. Inst. Nac. Hig ; 49(2): 16-23, 2018. tab, graf
Artículo en Español | LILACS, LIVECS | ID: biblio-1096285

RESUMEN

El toxoide tetánico es una neurotoxina modificada que induce la formación de una antitoxina protectora contra la enfermedad denominada tétanos. Este antígeno es obtenido a partir de procesos fermentativos con la bacteria anaerobia Clostridium tetani y es utilizado para la formulación de vacunas simples y combinadas inactivadas. Con el propósito de atender a las recomendaciones y regulaciones de la Organización Mundial de la Salud (OMS), el objetivo de este trabajo fue diseñar un Programa de Análisis de Peligros y Puntos Críticos de Control (HACCP) en la producción del antígeno Toxoide Tetánico, desde la recepción de la cepa certificada en el área de producción hasta el almacenamiento del toxoide tetánico purificado. Para ello, inicialmente se evaluó el cumplimiento de los prerequisitos (BPM, POES, BPL). Posteriormente, se procedió al diseño del plan HACCP mediante la ejecución de las 5 tareas preliminares y la aplicación de los 7 principios, conforme a la metodología descrita por la OMS. A partir del análisis de peligros en todas las etapas del proceso de producción del toxoide tetánico se identificaron 3 puntos críticos de control: detoxificación, filtración estéril final y almacenamiento de toxoide tetánico purificado. Se establecieron los límites críticos, los procedimientos de vigilancia, las acciones correctivas, los procedimientos de verificación y de documentación. La propuesta tiene como fin garantizar la calidad e inocuidad del producto elaborado, la protección del personal involucrado en el proceso y del medio ambiente con miras a la obtención de la certificación como laboratorio productor de vacunas


Tetanus toxoid is a modified neurotoxin that induces the formation of protective antitoxin of the disease called tetanus. This antigen is obtained from fermentation processes with anaerobic bacteria Clostridium tetani and it is used to formulate simple and combined inactivated vaccines. In order to meet the recommendations and regulations of World Health Organization (WHO), the aim of this work was to design a Program of Hazard Analysis and Critical Control Points (HACCP) in the production of antigen Tetanus Toxoid, starting from the receipt of the certified strain in the production area through the storage of purified tetanus toxoid. For this, initially fulfilling the prerequisites (GMP, SSOP and GLP) was evaluated. Subsequently, we proceeded to design HACCP plan by running 5 preliminary tasks and application of the 7 principles, according to the methodology described by WHO. From the hazard analysis at all stages of the production process of tetanus toxoid three critical control points were identified: detoxification, final sterile filtration and storage of purified tetanus toxoid. Critical limits, monitoring procedures, corrective actions, verification and documentation procedures were established. The proposal aims to assure the quality and safety of the final product, the protection of personnel involved in the process and the environment, with a view to obtaining certification as a vaccine production laboratory


Asunto(s)
Humanos , Masculino , Femenino , Tétanos , Antitoxinas , Toxoide Tetánico , Vacunas , Análisis de Peligros y Puntos de Control Críticos/métodos , Antígenos , Salud Pública , Neurotoxinas
13.
Cell Cycle ; 12(7): 1042-57, 2013 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-23428905

RESUMEN

Growth hormone (GH) overexpression throughout life in transgenic mice is associated with the development of liver tumors at old ages. The preneoplastic pathology observed in the liver of young adult GH-overexpressing mice is similar to that present in humans at high risk of hepatic cancer. To elucidate the molecular pathogenesis underlying the pro-oncogenic liver pathology induced by prolonged exposure to elevated GH levels, the activation and expression of several components of signal transduction pathways that have been implicated in hepatocellular carcinogenesis were evaluated in the liver of young adult GH-transgenic mice. In addition, males and females were analyzed in parallel in order to evaluate sexual dimorphism. Transgenic mice from both sexes exhibited hepatocyte hypertrophy with enlarged nuclear size and exacerbated hepatocellular proliferation, which were higher in males. Dysregulation of several oncogenic pathways was observed in the liver of GH-overexpressing transgenic mice. Many signaling mediators and effectors were upregulated in transgenic mice compared with normal controls, including Akt2, NFκB, GSK3ß, ß-catenin, cyclin D1, cyclin E, c-myc, c-jun and c-fos. The molecular alterations described did not exhibit sexual dimorphism in transgenic mice except for higher gene expression and nuclear localization of cyclin D1 in males. We conclude that prolonged exposure to GH induces in the liver alterations in signaling pathways involved in cell growth, proliferation and survival that resemble those found in many human tumors.


Asunto(s)
Hormona del Crecimiento/metabolismo , Hígado/patología , Animales , Núcleo Celular/metabolismo , Transformación Celular Neoplásica , Ciclina D1/metabolismo , Femenino , Expresión Génica , Hormona del Crecimiento/genética , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Tamaño de los Órganos , Fosforilación , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factores de Transcripción STAT/genética , Factores de Transcripción STAT/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Activación Transcripcional
15.
Arch Microbiol ; 189(4): 345-56, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18030448

RESUMEN

Main nodulation signal molecules in the peanut-bradyrhizobia interaction were examined. Flavonoids exuded by Arachis hypogaea L. cultivar Tegua were genistein, daidzein and chrysin, the latest being released in lower quantities. Thin layer chromatography analysis from genistein-induced bacterial cultures of three peanut bradyrhizobia resulted in an identical Nod factor pattern, suggesting low variability in genes involved in the synthesis of these molecules. Structural study of Nod factor by mass spectrometry and NMR analysis revealed that it shares a variety of substituents with the broad-host-range Rhizobium sp. NGR234 and Bradyrhizobium spp. Nodulation assays in legumes nodulated by these rhizobia demonstrated differences between them and the three peanut bradyrhizobia. The three isolates were classified as Bradyrhizobium sp. Their fixation gene nifD and the common nodulation genes nodD and nodA were also analyzed.


Asunto(s)
Arachis/química , Arachis/microbiología , Bradyrhizobium/química , Microbiología del Suelo , Simbiosis , Arachis/fisiología , Bradyrhizobium/clasificación , Bradyrhizobium/genética , Bradyrhizobium/fisiología , ADN Bacteriano/genética , ADN Ribosómico/genética , Flavonoides/química , Flavonoides/metabolismo , Lipopolisacáridos/química , Lipopolisacáridos/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Nódulos de las Raíces de las Plantas/química , Nódulos de las Raíces de las Plantas/metabolismo , Nódulos de las Raíces de las Plantas/microbiología , Análisis de Secuencia de ADN , Especificidad de la Especie
16.
J Acoust Soc Am ; 118(2): 605-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16158615

RESUMEN

A correcting formula for the estimation of harmonics-to-noise ratios (HNR) based on ensemble-averaging techniques is derived. The original method yields a biased approximation which is more accurate as the number of averaged pulses (N) increases. However, the method treats gradual waveform changes incorrectly as noise, which is worsened for large values of N. The obtained formula allows the use of as few averaged pulses as desired, while allowing the complete removal of the bias from the estimate of HNR.


Asunto(s)
Cómputos Matemáticos , Acústica del Lenguaje , Voz , Algoritmos , Humanos
17.
Biomacromolecules ; 6(3): 1448-56, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15877364

RESUMEN

We have determined the structure of a capsular polysaccharide from Sinorhizobium fredii HWG35. This polysaccharide was isolated following the standard protocols applied for lipopolysaccharide isolation. On the basis of monosaccharide analysis, methylation analysis, mass spectrometric analysis, one-dimensional (1)H and (13)C NMR, and two-dimensional NMR experiments, the structure was shown to consist of a polymer having the following disaccharide repeating unit: -->6)-2,4-di-O-methyl-alpha-d-Galp-(1-->4)-beta-d-GlcpA-(1-->. Strain HWG35 produces a capsular polysaccharide that does not show the structural motif (sugar-Kdx) observed in those S. fredii strains that, while effective with Asiatic soybean cultivars, are unable to form nitrogen-fixing nodules with American soybean cultivars. Instead, the structure of the capsular polysaccharide of S. fredii HWG35 is in line with those produced by strains HH303 (rhamnose and galacturonic acid) and B33 (4-O-methylglucose-3-O-methylglucuronic acid), two S. fredii strains that form nitrogen-fixing nodules with both groups of soybean cultivars. Hence, in these three strains that effectively nodulate American soybean cultivars, the repeating unit of the capsular polysaccharide is composed of two hexoses, one neutral (methylgalactose, rhamnose, or methylglucose) and the other acidic (glucuronic, galacturonic, or methylglucuronic acid).


Asunto(s)
Polisacáridos Bacterianos/análisis , Polisacáridos Bacterianos/química , Sinorhizobium fredii/aislamiento & purificación , Conformación de Carbohidratos
18.
Mamm Genome ; 14(3): 157-67, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12647238

RESUMEN

Mocha (mh), a mouse model for Hermansky-Pudlak syndrome (HPS), is characterized by platelet storage pool deficiency, pigment dilution, and deafness as well as neurological abnormalities. The trans-Golgi/endosome adaptor-related complex AP-3 is missing in mh mice owing to a deletion in the gene encoding the delta subunit. Mice mutant for a second allele, mh(2J), are as hyperactive as mh, and display both spike wave absence and generalized tonic clonic seizures, but have less coat color dilution, no hearing loss, and no hypersynchronized EEG. Here we show that the mh(2J) mutation is due to an IAP element insertion in the Ap3d gene leading to a C-terminally truncated protein. Despite correct assembly of the AP-3 complex and localization to the trans-Golgi network and endosomes, AP-3 function in neurons remains impaired. While mh mice show a severe reduction of vesicular zinc (TIMM staining) owing to mislocalization and degradation of the Zinc transporter ZnT-3, the TIMM and ZnT-3 staining patterns in mh(2J) varies, with normal expression in hippocampal mossy fibers, but abnormal patterns in neocortex. These results indicate that the N-terminal portion of the delta subunit is sufficient for AP-3 complex assembly and subcellular localization to the TGN/endosomes, while subsequent function is regulated in part by cell-specific interactions with the C-terminal portion.


Asunto(s)
Elementos Transponibles de ADN , Genes de Partícula A Intracisternal , Síndrome de Hermanski-Pudlak/genética , Animales , Modelos Animales de Enfermedad , Ratones , Fenotipo , Análisis de Secuencia de ADN
19.
Rev. cuba. salud pública ; 29(3)jul.-sept. 2003. tab
Artículo en Español | LILACS | ID: lil-401136

RESUMEN

Con el objetivo de conocer el estado nutricional de las vitaminas B1 y B2 en ancianos no institucionalizados se estudiaron 50 individuos mayores de 60 años de 2 áreas de salud del municipio Centro Habana. Los niveles de las vitaminas B1 y B2 fueron determinados mediante las técnicas de estimulación de las enzimas eritrocitarias transcetolasa y glutatión reductasa, se midieron el peso corporal y las distancias hombro-codo y rodilla-talón para evaluar el índice de masa corporal (IMC). La ingestión dietética de estas vitaminas se estimó por una encuesta cuantitativa por registro de alimentos de 3 días en una submuestra de 21 ancianos. Se indagó sobre hábitos tóxicos y uso de suplementos vitamínicos. Se encontró que el 65 y el 64(por ciento) de los ancianos tenían niveles deficientes y subóptimos de vitaminas B1 y B2 respectivamente. Aproximadamente el 40(por ciento) de los ancianos no cumplían el 50(por ciento) de las recomendaciones diéteticas diarias para ambas vitaminas. No se hallaron diferencias significativas de los niveles de las vitaminas entre sexos. Alrededor del 60(por ciento) tenía un adecuado IMC. El IMC fue significativamente mayor en las mujeres, los mayores de 80 años tenían un IMC significativamente menor. No se encontró asociación entre el IMC y los niveles subóptimos de las vitaminas. Los niveles de vitaminas no variaron según el hábito de fumar y el consumo de bebidas alcohólicas. Sólo el 36(por ciento) de los ancianos consumía vitaminas como suplemento dietético; había mayor proporción de individuos deficientes de ambas vitaminas en el grupo no consumidor. Estos resultados demuestran la necesidad de mejorar el estado nutricional de estas vitaminas en este grupo de población


Asunto(s)
Humanos , Masculino , Femenino , Anciano , Composición Corporal , Cuba , Indicadores de Salud , Estado Nutricional , Deficiencia de Riboflavina , Deficiencia de Tiamina
20.
Rev. cuba. estomatol ; 35(3): 124-126, sep.-dic. 1998.
Artículo en Español | LILACS | ID: lil-628309

RESUMEN

Se reporta un inusual caso de granulomatosis de células de Langerhans localizado en maxilares en un paciente de 30 meses de edad, quien presentaba además de las lesiones líticas óseas, lesiones de aspecto tumoral en encía palatina y lingual de ambas arcadas dentarias. El examen óseo no arrojaba compromiso de otros huesos. El diagnóstico histológico fue corroborado por el Centro Nacional de Referencia en Anatomía Patológica.


A unusual case of Langerhans´ cells is reported, located in maxillae of a 30 months old patients, who, apart from bone lithic injuries, showed injuries of tumoral type in lingual and palatine gingiva of both dental archs. According to bone examination, there weren´t involvement of other bones. Histologic diagnosis was corroborated by National Reference Center in Pathologic Anatomy.

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