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1.
Phys Rev E ; 109(1-1): 014230, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38366434

RESUMEN

Recent evidence shows that heteroclinic bifurcations in magnetic islands may be caused by the amplitude variation of resonant magnetic perturbations in tokamaks. To investigate the onset of these bifurcations, we consider a large aspect ratio tokamak with an ergodic limiter composed of two pairs of rings that create external primary perturbations with two sets of wave numbers. An individual pair produces hyperbolic and elliptic periodic points, and its associated islands, that are consistent with the Poincaré-Birkhoff fixed-point theorem. However, for two pairs producing external perturbations resonant on the same rational surface, we show that different configurations of isochronous island chains may appear on phase space according to the amplitude of the electric currents in each pair of the ergodic limiter. When one of the electric currents increases, isochronous bifurcations take place and new islands are created with the same winding number as the preceding islands. We present examples of bifurcation sequences displaying (a) direct transitions from the island chain configuration generated by one of the pairs to the configuration produced by the other pair, and (b) transitions with intermediate configurations produced by the limiter pairs coupling. Furthermore, we identify shearless bifurcations inside some isochronous islands, originating nonmonotonic local winding number profiles with associated shearless invariant curves.

2.
Hand Surg Rehabil ; 40(6): 715-721, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34425267

RESUMEN

The goal of this systematic review and meta-analysis was to compare nerve conduits and nerve graft for peripheral nerve regeneration. This type of lesion frequently causes disability due to pain, paresthesia and motor deficit. On the PICO process, "P" corresponded to patients with peripheral digital nerve lesions of any age, gender or ethnicity, "I" to interventions with nerve conduits or nerve graft, "C" to the control group with no treatment, placebo or receiving other treatment, and "O" to outcome assessment of nerve regeneration. Initial search found in 3859 studies, including 2001 duplicates. The remaining 1858 studies were selected by title and/or abstract; 1798 articles were excluded, leaving 60 articles for full-text review. Thirty-nine of these 60 reports were excluded as not meeting our inclusion criteria, and 21 articles were ultimately included in the systematic review. For patients older than 40 years, there was a greater mean improvement on S2PD and M2PD tests with grafting, which seemed to be the better surgical technique, positively impacting prognosis. On the M2PD test, there was significantly greater improvement in 11-17.99 mm defects with grafting (P < 0.001); this finding should guide surgical strategy in peripheral nerve regeneration, to ensure better outcomes.


Asunto(s)
Traumatismos de los Nervios Periféricos , Humanos , Regeneración Nerviosa/fisiología , Procedimientos Neuroquirúrgicos , Traumatismos de los Nervios Periféricos/cirugía , Nervios Periféricos/trasplante , Prótesis e Implantes
3.
Eur J Neurol ; 27(4): 660-666, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31746515

RESUMEN

BACKGROUND AND PURPOSE: Genetic generalized epilepsies (GGEs) encompass a group of syndromes of mainly genetic causes, characterized by the involvement of both hemispheres. MicroRNAs (miRNAs) are small non-coding RNAs with a critical role in the regulation of neuronal biological processes through gene expression modulation. Dysregulated miRNA expression has been shown in epilepsy. Due to their stability in biological fluids like serum, miRNAs have assumed a prominent role in biomarker research. Our aim was to evaluate circulating levels of three miRNAs in GGE patients and assess their putative diagnostic value. METHODS: MiR-146a, miR-155 and miR-132 were quantified by real-time polymerase chain reaction in the serum of 79 GGE patients (47 women, 32 men, 35.1 ± 12.4 years) and 67 healthy individuals (41 women, 26 men, 42.4 ± 10.1 years). Relative expression values were calculated using the 2-ΔΔCt method. Receiver operating characteristic curve analysis was performed to assess diagnostic value. MiRNA expression was correlated with clinicopathological features. RESULTS: Serum levels of miR-146a and miR-155 were significantly upregulated in GGE patients relative to controls (3.13 and 6.05, respectively). Combined miR-146a, miR-155 and miR-132 serum levels performed well as a diagnostic biomarker, discriminating GGE patients from controls with an area under the curve of 0.85, 80% specificity and 73% sensitivity. CONCLUSIONS: Our results indicate that miR-146a, miR-155 and miR-132 may partake in GGE epileptogenesis. A panel of three circulating miRNAs with potential value as a GGE biomarker is reported for the first time. Novel biomarkers may help to identify new treatment targets and contribute to improved patients' quality of life through earlier diagnosis and a more precise prognosis.


Asunto(s)
MicroARN Circulante/sangre , Epilepsia Generalizada/diagnóstico , Adulto , Biomarcadores/sangre , Epilepsia Generalizada/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Calidad de Vida , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Adulto Joven
4.
Rev. chil. nutr ; 46(2): 154-159, abr. 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1003688

RESUMEN

ABSTRACT The aim of this work was to process jabuticaba skin aqueous extract, varying the crushing and sieving time and to develop ice cream with different concentrations of jabuticaba skin extract, evaluate its physicochemical, microbiological and bioactive composition. Different extractive processes of jabuticaba skin were tested. Extract A was crushed for 25 seconds and sieved, extract B was crushed for 25 seconds without sieving, extract C was crushed for 45 seconds and sieved and extract D was crushed during 45 seconds not sifted. From the extract that presented the highest indices of bioactive compounds, formulations of ice cream with concentrations of 5, 10 and 15% were elaborated. Extract B showed the highest content of phenolic compounds (201.81 mg gallic acid. 100 g-1 skins), anthocyanins (60.32 mg cyanidin-3 glycoside.100 g-1 peels) and significant antioxidant activity (5047.72 g skins. g-1 DPPH) and was chosen to be added in the ice cream. The evaluated ice creams met the microbiological standards established by the Brazilian legislation. The use of progressive concentrations of jabuticaba skin extract in the elaboration of ice cream increased the rates of phenolic compounds and antioxidant capacity. The values found were significant and generated an alternative use for jabuticaba skin, which is normally discarded.


RESUMEN El objetivo de este trabajo fue elaborar extractos acuosos de piel de jabuticaba, variando el tiempo de trituración y cribado. Además de desarrollar helados con diferentes concentraciones de extracto de piel de jabuticaba, evaluando su composición físico-química, microbiológica y de compuestos bioactivos. Se analizaron diferentes procesos de elaboración de extractos de cáscara de jabuticaba, siendo denominados extracto A - triturado durante 25 segundos y tamizado, extracto B - triturado durante 25 segundos no tamizado, extracto C - triturado durante 45 segundos y tamizado y extracto D - triturado durante 45 segundos sin cribado. A partir del extracto que presentó los índices más elevados de compuestos bioactivos, se elaboraron formulaciones de helado con concentraciones de 5, 10 y 15%. El extracto B fue el que presentó mayor contenido de compuestos fenólicos (201,81 mg ácido gálico. 100 g-1 piel), antocianinas (60,32 mg cyanidina-3 glycosideo.100 g-1 piels) y significativa actividad antioxidante (5047,72 g piels. g-1DPPH) siendo el elegido para ser añadido en el helado. Los helados evaluados se encuentran dentro de los patrones microbiológicos estabelecidos por la legislación brasileña. La utilización de concentraciones progresivas de extracto de piel de jabuticaba en la elaboración de helado incrementó los índices de compuestos fenólicos y de capacidad antioxidante. Los valores encontrados son significativos y genera una alternativa en el aprovechamiento de la piel de jabuticaba, normalmente descartada.


Asunto(s)
Extractos Vegetales , Helados Comestibles , Compuestos Fenólicos , Ingredientes Alimentarios , Antioxidantes
5.
Plant Biol (Stuttg) ; 21(1): 122-132, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30195257

RESUMEN

Hybridization is a widespread phenomenon present in numerous lineages across the tree of life. Its evolutionary consequences range from effects on the origin and maintenance, to the loss of biodiversity. We studied genetic diversity and intra- and interspecific gene flow between two sympatric populations of closely-related species, Pitcairnia flammea and P. corcovadensis (Bromeliaceae), which are adapted to naturally fragmented Neotropical inselbergs, based on nuclear and plastidial DNA. Our main results indicate a strong reproductive isolation barrier, although low levels of interspecific gene flow were observed in both sympatric populations. The low rates of intraspecific gene flow observed for both P. corcovadensis and P. flammea populations corroborate the increasing body of evidence that inselberg bromeliad species are maintained as discrete evolutionary units despite the presence of low genetic connectivity. Nuclear patterns of genetic diversity and gene flow revealed that hybridization and introgression might not cause species extinction via genetic assimilation of the rare P. corcovadensis. In the face of reduced intraspecific gene exchange, hybridization and introgression may be important aspects of the Pitcairnia diversification process, with a positive evolutionary impact at the bromeliad community level, and thus contribute to increasing and maintaining genetic diversity in local isolated inselberg populations.


Asunto(s)
Bromeliaceae/genética , Hibridación Genética , Aislamiento Reproductivo , Brasil , ADN de Cloroplastos/genética , Flujo Génico , Variación Genética , Geografía , Haplotipos/genética , Especificidad de la Especie
6.
J Insect Sci ; 18(3)2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29901739

RESUMEN

Within the cattle fever tick quarantine zone along the Rio Grande, a steady displacement of native vegetation by Arundo donax L. has been occurring for over a century. Arundo rapidly grows to a height of 3-6 m creating a dense wall of vegetation impeding surveillance and interception of stray cattle breaching the cattle fever tick quarantine from Mexico. Additionally, arundo monocultures may decrease the number and diversity of predatory beetles feeding on cattle fever ticks. To compare predatory beetle abundance and diversity within and between arundo and native vegetation, beetles were trapped at 10 locations twice a month for 16 mo (=38,400 trap nights) in the cattle fever tick quarantine zone along the Mexico-American border between Brownsville and Del Rio, TX. In total, 766 beetles were trapped, which included 34 genera and 43 species. Native vegetation provided more beetles, greater species richness, and increased biological diversity. Thus, greater beetle diversity was found in the more complex native vegetation compared with arundo stands. However, because predatory beetle sample numbers were modest, it is unlikely these mostly polyphagous, opportunistic arthropod predators would apply much pressure on tick populations, leading us to conclude that beetle predation would have little effect on tick populations in native vegetation or within stands of arundo.


Asunto(s)
Biodiversidad , Escarabajos , Especies Introducidas , Poaceae , Animales , Texas
7.
Parasitology ; 145(7): 927-938, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29144218

RESUMEN

Salivary molecules, as glycine-rich proteins (GRPs), are essential to tick attachment and feeding on the host and are suggested to be involved in the host's immune system evasion, therefore representing natural candidates in the search for protective vaccine antigens. This work shows the molecular characterization of a GRP from Rhipicephalus microplus (RmGRP). The cDNA and putative amino acid sequences were analysed, as well as the transcription level in tick tissues/developmental stages, showing the highest levels of gene expression in 1-day-old larvae and salivary glands of fully engorged females. RmGRP gene silencing resulted in a lower hatching rate of larvae from treated females. In addition, recombinant RmGRP (rRmGRP) was recognized by sera from naturally and experimentally infested bovines, displaying considerable differences among the individuals tested. rRmGRP was recognized by anti-saliva and anti-salivary glands sera, while anti-rRmGRP serum recognized RmGRP in saliva and salivary glands, indicating its secretion into the host. The data collected indicate that RmGRP may present roles other than in the tick-host relationship, especially in embryo development. In addition, the high expression in adult females, antigenicity and presence of shared characteristics with other tick protective GRPs turns RmGRP a potential candidate to compose an anti-tick vaccine cocktail.


Asunto(s)
Proteínas de Artrópodos/química , Glicina/química , Interacciones Huésped-Parásitos , Rhipicephalus/genética , Proteínas y Péptidos Salivales/química , Animales , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Bovinos/parasitología , ADN Complementario , Femenino , Perfilación de la Expresión Génica , Larva/genética , Estructura Secundaria de Proteína , Interferencia de ARN , Proteínas y Péptidos Salivales/genética , Proteínas y Péptidos Salivales/inmunología , Infestaciones por Garrapatas/inmunología
8.
Clin Exp Immunol ; 189(3): 318-330, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28542701

RESUMEN

Forkhead box P3 (FoxP3)+ regulatory T cells (Tregs ) are functionally deficient in systemic lupus erythematosus (SLE), characterized by reduced surface CD25 [the interleukin (IL)-2 receptor alpha chain]. Low-dose IL-2 therapy is a promising current approach to correct this defect. To elucidate the origins of the SLE Treg phenotype, we studied its role through developmentally defined regulatory T cell (Treg ) subsets in 45 SLE patients, 103 SLE-unaffected first-degree relatives and 61 unrelated healthy control subjects, and genetic association with the CD25-encoding IL2RA locus. We identified two separate, uncorrelated effects contributing to Treg CD25. (1) SLE patients and unaffected relatives remarkably shared CD25 reduction versus controls, particularly in the developmentally earliest CD4+ FoxP3+ CD45RO- CD31+ recent thymic emigrant Tregs . This first component effect influenced the proportions of circulating CD4+ FoxP3high CD45RO+ activated Tregs . (2) In contrast, patients and unaffected relatives differed sharply in their activated Treg CD25 state: while relatives as control subjects up-regulated CD25 strongly in these cells during differentiation from naive Tregs , SLE patients specifically failed to do so. This CD25 up-regulation depended upon IL2RA genetic variation and was related functionally to the proliferation of activated Tregs , but not to their circulating numbers. Both effects were found related to T cell IL-2 production. Our results point to (1) a heritable, intrathymic mechanism responsible for reduced CD25 on early Tregs and decreased activation capacity in an extended risk population, which can be compensated by (2) functionally independent CD25 up-regulation upon peripheral Treg activation that is selectively deficient in patients. We expect that Treg -directed therapies can be monitored more effectively when taking this distinction into account.


Asunto(s)
Familia , Subunidad alfa del Receptor de Interleucina-2/genética , Lupus Eritematoso Sistémico/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Femenino , Citometría de Flujo , Humanos , Interleucina-2/biosíntesis , Interleucina-2/inmunología , Subunidad alfa del Receptor de Interleucina-2/inmunología , Antígenos Comunes de Leucocito/genética , Antígenos Comunes de Leucocito/inmunología , Antígenos Comunes de Leucocito/metabolismo , Lupus Eritematoso Sistémico/fisiopatología , Activación de Linfocitos/inmunología , Masculino , Persona de Mediana Edad , Fenotipo , Linfocitos T Reguladores/clasificación , Regulación hacia Arriba , Adulto Joven
9.
Hum Exp Toxicol ; 36(1): 33-41, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26944940

RESUMEN

Pentavalent antimonial (Sb5+) drugs such as meglumine antimoniate (MA) are the mainstay treatment of leishmaniases in developing countries. The effects of these compounds on drug-metabolizing enzymes have not been characterized and their potential pharmacokinetic interactions with other drugs are therefore unknown. The present study investigated whether treatment with MA (300 mg Sb5+/kg body weight/day, subcutaneously) for 24 days affected the activities of cytochrome P450 (CYP)1A (ethoxyresorufin- O-deethylase), CYP2A5 (coumarin 7-hydroxylase), CYP2E1 ( p-nitrophenol-hydroxylase), CYP2B9/10 (benzyloxy-resorufin- O-debenzylase), or CYP3A11 (erythromycin- N-demethylase) in the livers of Swiss Webster (SW) and DBA-2 male and female mice. The results showed that CYP2A5-, CYP2E1-, and CYP3A11-catalyzed reactions were unaffected by MA treatment. A decrease in CYP2B9/10 activity was noted in DBA-2 females (but not males) and was not observed in SW males or females. However, repeated MA administration reduced mouse liver CYP1A activity. CYP1A2 messenger RNA (mRNA) levels were not affected by MA and in vitro exposure of mouse liver microsomes to Sb3+ and Sb5+ did not reduce CYP1A activity. These findings suggested that in vivo treatment with Sb5+ drugs depressed CYP1A activity, without downregulating CYP1A2 mRNA expression. Since in vitro treatment of liver microsomes failed to inhibit CYP1A activity, this effect may require intact cells.

10.
Lupus ; 24(8): 846-53, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25661837

RESUMEN

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown origin, in which both genetic and environmental factors are involved. One such environmental factor is vitamin D, a vital hormone that plays a specific function in the immune system homeostasis, acting through a nuclear receptor (VDR) expressed in all immune cells. Several polymorphisms of the gene that encodes this receptor have been described. Though inconsistently, these polymorphisms have been associated with clinical manifestations and SLE development.The aim of this study was to determine the possible association between VDR gene polymorphisms (BsmI, ApaI, TaqI e FokI) and SLE susceptibility and severity, in a cohort of lupus patients from the north of Portugal.A total of 170 patients (F = 155, M = 15; age = 45 ± 13.4 years) with SLE (diagnosed according the American College of Rheumatology criteria) with at least five years of disease evolution and followed in the Autoimmune Disease Clinical Immunology Unit of Centro Hospitalar do Porto were studied. Patients and 192 ethnicity-matched controls were genotyped for BsmI (rs1544410), ApaI (rs7975232), TaqI (rs731236) and FokI (rs2228570) polymorphisms by TaqMan allelic discrimination assay. Disease severity was assessed by SLICC damage score, number of affected organs, number of severe flares and pharmacological history.SLE patients with the CT genotype of FokI polymorphism have a higher SLICC value (p = 0.031). The same result was observed for the group of patients with the TT genotype of TaqI polymorphism (p = 0.046). No differences were observed in VDR genotype between patients and controls. Also, we observed that the other clinical features analysed were not influenced by VDR polymorphisms.Our study confirms a possible role of VDR gene polymorphisms in SLE. A positive association was found between VDR polymorphisms and SLE severity (chronic damage). The presence of CT genotype of FokI and TT genotype of TaqI seems to confer a worse prognosis and may constitute a risk factor for higher long-term cumulative damage in SLE patients.


Asunto(s)
Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/genética , Receptores de Calcitriol/clasificación , Receptores de Calcitriol/genética , Adulto , Alelos , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Portugal , Factores de Riesgo , Deficiencia de Vitamina D/etiología
11.
Int J Immunogenet ; 41(3): 236-41, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24164722

RESUMEN

Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease with strong genetic and environmental components. Previous studies have shown increased levels of several chemokines in active SLE. C-C chemokine receptor type 5 (CCR5) is involved in the recruitment of inflammatory cells into tissues, and mechanisms modulating CCR5 expression and function may interfere in SLE development, influencing the clinical course of the disease. The aim of this study was to evaluate the possible association between the CCR5∆32 base-pair deletion polymorphism and SLE disease in a group of Portuguese patients. A total of 219 patients with SLE and 205 healthy individuals were studied. The frequency of CCR5/∆32 heterozygotes was lower in patients with SLE than in controls (8% vs. 15% OR = 0.5162; P = 0.0319), suggesting a protective association between CCR5∆32 allele and SLE. These results highlight the protective role of Th1 cells that express CCR5 in SLE pathogenesis.


Asunto(s)
Secuencia de Bases , Lupus Eritematoso Sistémico/genética , Receptores CCR5/genética , Eliminación de Secuencia , Células TH1/metabolismo , Adulto , Alelos , Estudios de Casos y Controles , Femenino , Expresión Génica , Frecuencia de los Genes , Heterocigoto , Humanos , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/patología , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Portugal , Índice de Severidad de la Enfermedad , Células TH1/inmunología , Células TH1/patología
12.
Med. cután. ibero-lat.-am ; 41(3): 111-117, mayo-jun. 2013. ilus
Artículo en Español | IBECS | ID: ibc-117823

RESUMEN

Todos los organismos se componen principalmente de agua. La mayoría de las membranas biológicas exhiben una elevada permeabilidad al agua, hecho que les permite a los compartimientos intra y extracelular mantener la isotonicidad necesaria para la homeostasis intracelular, aunque los mecanismos responsables de ello han sido tema de controversia. El agua puede atravesar la membrana por difusión simple o a través de poros acuosos. Si bien durante mucho tiempo se había asumido que el transporte de agua ocurría exclusivamente mediante el primer mecanismo, en la década de los 60 surgieron trabajos de investigadores pioneros en el tema que culminaron con el descubrimiento de los canales o poros de agua llamados Acuaporinas por parte del biólogo Peter Agre. Las acuaporinas son una familia de proteínas homólogas transportadoras de agua expresadas en células epiteliales, endoteliales y otras células de mamíferos, las cuales han permitido comprender mejor los mecanismos utilizados por la célula para el control de los flujos de agua a través de la membrana y por ende, la regulación de su osmolaridad interna. destaca por su potencial utilidad en el tratamiento de condiciones dermatológicas, pues, además del agua, conduce otras moléculas orgánicas pequeñas como la glicerina o la urea, además de poder ser estimulada en forma selectiva. El presente trabajo pretendió resumir al conocimiento que se tiene en la actualidad en torno a las Aquaporinas, con particular énfasis en , así como establecer sus posibilidades futuras en Dermatología


Every living organism is mainly composed of water. Most biological membranes exhibit an increased permeability to water, which allows intra- and extra-cellular compartments to maintain the isotonicity required for intracellular homeostasis, although underlying mechanisms for this are still subject ofdebate. Water can cross the membranes through simple diffusion or by aqueous pores. While water transport was assumed to occur exclusively by thefirst mechanism, pioneer studies conducted through the sixties revealed otherwise, ultimately leading to the discovery by biologist Peter Agre of waterchannels or pores called Aquaporins. Aquaporins are a family of water-transporter homologous proteins expressed by epithelial, endothelial and othertypes of cells in mammals, which allowed a better understanding of the mechanisms used by the cell to control the flow of water through the membrane,and therefore, the regulation of its inner osmolarity. Aquaporin-3 (AQP3) is particularly important for its potential role in the treatment of skin conditions,since it may transport small organic molecules other than water, like glycerin or urea and may be stimulated selectively. This paper was intended to sum-marize the current knowledge on Aquaporins, with a particular emphasis on AQP3, and to delineate its possible future roles in Dermatology


Asunto(s)
Humanos , Acuaporina 3/uso terapéutico , Fluidoterapia/métodos , Equilibrio Hidroelectrolítico/fisiología , Enfermedades de la Piel , Permeabilidad , Acuaporinas/fisiología
13.
Radiat Prot Dosimetry ; 145(2-3): 320-4, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21467584

RESUMEN

In Mexico City there are more than 22 millions of inhabitants (10 in the metropolitan area and 12 in the suburban zone) exposed to drinking water. The local epidemiological authorities recognised that exposure to radon contaminated drinking water is a potential health hazard, as has been considered worldwide. The United States Environmental Protection Agency has proposed a limit of 11.1 Bq l(-1) for the radon level in drinking water. In Mexico a maximum contamination level of radon in drinking water has not yet even considered. In this work, a (222)Rn study of drinking water in Mexico City has revealed a range of concentrations from background level to 3.8 Bq l(-1). (222)Rn was calculated using a portable degassing system (AquaKIT) associated with an AlphaGUARD measuring system. Samples from 70 wells of the water system of the south of the Valley Basin of Mexico City and from houses of some other political administrative divisions of Mexico City were taken.


Asunto(s)
Monitoreo de Radiación , Radón/análisis , Contaminantes Radiactivos del Agua/análisis , Humanos , México , Abastecimiento de Agua
14.
Arq. bras. med. vet. zootec ; 63(2): 273-278, abr. 2011. ilus, tab
Artículo en Portugués | LILACS | ID: lil-591115

RESUMEN

Foram utilizados 12 pares de úmeros obtidos de bezerros machos da raça Holandesa, com idades entre 15 e 30 dias. Os úmeros esquerdos foram mantidos íntegros, e os direitos foram fraturados de forma oblíqua em sua diáfise, na transição entre os terços médio e proximal. A redução da fratura foi feita pela aplicação intramedular de haste de polipropileno, bloqueada por dois parafusos corticais de aço inoxidável, dispostos transversalmente em cada fragmento ósseo. Seis pares de ossos foram submetidos ao teste de compressão, e seis ao teste de flexão, utilizando-se uma máquina universal de ensaios. Nos testes de compressão, as cargas médias de ruptura foram 738,3N e 473,3N, e nos testes de flexão 322,4N e 117,9N, para os ossos íntegros e fraturados, respectivamente. Comparando-se o grupo de ossos fraturados com o grupo de ossos íntegros, verificou-se que o sistema proposto foi capaz de resistir a 66,4 por cento das cargas médias quando submetido à compressão, e a 36,6 por cento quando submetido à flexão. Úmeros fraturados e tratados com haste intramedular de polipropileno apresentaram resistência limitada se comparados aos ossos íntegros.


A total of 12 pairs of humeri from male calves 15 to 30 days old were used. The left humeri remained unchanged and the right ones were fractured in the diaphysis between proximal and middle thirds. The fracture was fixed with a polypropylene intramedullary nail interlocked with two steel bone screws crossed along each segment. Six pairs of bones were subjected to a compression test and the others to a flexural test using a universal testing machine. In the compression tests, the mean rupture loads were 738,3N and 473,3N, and in the flexural tests they were 322,4N and 117,9N for the intact and fractured bones respectively. Fractured bones fixed with the proposed model were able to resist 66.4 percent of the load during compression and 36.6 percent during bending when in comparison to intact bones. Fractured humeri treated with polypropylene intramedullary nail showed limited resistance compared to intact ones.


Asunto(s)
Bovinos , Fenómenos Biomecánicos/métodos , Bovinos/lesiones , Fijación Interna de Fracturas , Fracturas Óseas/veterinaria , Ortopedia/tendencias , Polipropilenos
15.
Arq. bras. med. vet. zootec ; 63(1): 6-11, Feb. 2011. ilus, tab
Artículo en Portugués | LILACS | ID: lil-582317

RESUMEN

Avaliou-se a ocorrência da doença infundibular (DI) e a associação entre sobremordida (SM) e ganchos dentários rostral e caudal da maxila e mandíbula. Utilizaram-se 88 equinos - 52 machos e 36 fêmeas -, entre três e 27 anos. Para os exames odontológicos, os animais foram contidos em brete e sedados com xilazina 10 por cento a 0,5mg/kg IV e utilizaram-se abridor de boca, fotóforo elétrico e sonda odontológica de aço inox. Agruparam-se os equinos por idade. O grupo 1 foi formado por animais até nove anos; o G2 de 10 a 14 e G3 de 15 a 27 anos. Foi diagnosticada DI em (37,5 por cento) animais, nos dentes molares e pré-molares. A incidência maior de DI foi nos dentes 109 (11,4 por cento) e 209 (12,5 por cento). Houve correlação positiva entre a idade e o número de dentes acometidos (r=0,26; P<0,02). A maior ocorrência de DI no grupo mais acometido (G3) foi nos dentes 108 e 208. Verificaram-se 66 por cento de SM e 65 por cento de ganchos. Observou-se correlação entre SM e presença total de ganchos (r=0,26, P=0,016), entre SM e ganchos rostrais maxilares e mandibulares (r=0,25,P=0,016) e ganchos rostrais maxilares(r=0,24, P=0,02). Animais com ganchos pré-molares maxilares tiveram 2,8 vezes mais chance de apresentarem SM (IC 95 por cento = 1,1 a 7,1).


The occurrence of infundibular disease (ID) and the association between over-bite (OB) and rostral and caudal hooks on teeth of the maxilla and jaw were evaluated in 88 horses - 52 males and 36 females - aging from between 3 and 27 years old. The horses were restrained in stocks, sedated with xylazine and examined using a mouth-speculum and a stainless steel pick. The data were recorded on individual charts. The animals were grouped by age: group 1: 3 to 9, group 2: 10 to 14, and group 3: 15 to 27 years old. ID was identified on the premolar and molar teeth in 37.5 percent of horses. There was a positive correlation between age and number of affected teeth (r=0.26, P<0.02). The most affected teeth were the 109 (11.4 percent) and 209 (12.5 percent). The highest occurrence of ID in the most affected group (G3) was on the 108 and 208 teeth. There were 66 percent of OB and 65 percent of hooks. There was a correlation between OB and the presence of total (r=0.26, P=0.016), maxillary and mandibular (r=0.25, P=0.016), and maxillary rostral hooks (r=0.24, P=0.02). Only the association between OB and maxillary rostral hooks was significant. Animals with maxillary pre-molars hooks were 2.8 times predisposed to have OB (CI 95 percent=1.1 to 7.1).


Asunto(s)
Animales , Caballos/clasificación , Odontología/veterinaria , Diente Premolar , Diente Molar/anatomía & histología
16.
Salud ment ; 33(6): 489-497, nov.-dic. 2010. tab
Artículo en Español | LILACS-Express | LILACS | ID: lil-632808

RESUMEN

Introduction Tobacco consumption is a serious public health problem and the principal cause of death worldwide. It is linked to chronic obstructive pulmonary disease (COPD), coronary disease, and various cancers such as lung cancer, which is the most frequent, and cancer of the larynx and other organs. Smoking affects the quality of life of millions of people. Those who live with smokers also become involuntary or passive smokers. It is important to determine the factors that influence initiation and continuation of smoking and the reasons that facilitate or favor smoking cessation. The dependence of cigarette smoking acts as a modulator of the relationship that smokers have with their social environment and on the expression of their feelings. We considered important to study the assertiveness of smokers, which is considered to be the social skill that individuals have to express what they think, feel and opine about respecting their rights and the rights of others as a factor that may influence smoking cessation or continuation of smoking. Objective We undertook this study to determine the levels of assertiveness and the sociodemographic profile of a population of 130 patients who were smokers and who came to the <

Introducción El tabaquismo es un problema de salud pública, es la principal causa de muerte evitable en el mundo, se vincula a padecimientos -como enfermedad pulmonar obstructiva crónica (EPOC), enfermedad coronaria y diversos cánceres, como el de pulmón, que es el más frecuente, y el de laringe- y afecta la calidad de vida de miles de seres. Los que conviven con el fumador se convierten en <

17.
Br J Cancer ; 101(8): 1329-37, 2009 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-19826426

RESUMEN

BACKGROUND: Elderly individuals react less efficiently to vaccines than do adults, mainly because of T-cell unresponsiveness. In this study, we analysed whether tumour-associated antigen (TAA)-specific CD8 T-cell responses could be induced by vaccination in old mice with metastatic breast cancer. METHODS: The effect of pcDNA-3.1- and Listeria-based vaccines, expressing TAA Mage-b, on Mage-b-specific immune responses was tested in spleens and draining lymph nodes (LNs) of mild (4TO7cg) and aggressive (4T1) syngeneic metastatic mouse breast tumour models at young (3 months) and old (20 months) age. RESULTS: Interferon gamma and interleukin-2 levels increased significantly in draining LNs and spleens of Mage-b-vaccinated mice compared with those in control groups at young but not old age in both mouse tumour models. A significant increase was observed in the number of IFNgamma-producing Mage-b-specific CD8 T cells after Mage-b vaccination in the 4T1 model at young but not old age. This correlated with a reduced protective effect of Mage-b vaccination against metastatic breast cancer at old compared with young age. CONCLUSIONS: The absence of CD8 T-cell responses after Mage-b vaccination and the accompanying reduced protection against metastatic breast cancer in old compared with young mice point towards the need for tailoring cancer vaccination to older age.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/inmunología , Neoplasias Mamarias Animales/terapia , Proteínas de Neoplasias/inmunología , Vacunación , Vacunas de ADN/inmunología , Factores de Edad , Animales , Femenino , Neoplasias Mamarias Animales/inmunología , Neoplasias Mamarias Animales/patología , Ratones , Ratones Endogámicos BALB C , Proteínas de Neoplasias/genética
18.
Rev. colomb. ciencias quim. farm ; 37(2): 133-149, dic. 2008.
Artículo en Español | LILACS | ID: lil-557440

RESUMEN

La presente investigación, de interés en salud pública en el área de Odontología, evaluó la acción de tres desinfectantes (glutaraldehído, hipoclorito de sodio y cloruro de benzalconio) frente a superficies susceptibles con mayor contaminación bacteriana en unidades dentales de uso continuo, comparando la población bacteriana antes y después de la desinfección. Se seleccionaron tres superficies (jeringa triple, testera de la silla, escupidera) por medio de cuestionarios al personal de las clínicas odontológicas de la Universidad Antonio Nariño - Sede Sur. Los microorganismos encontrados fueron similares para todas las unidades dentales, con prevalencia de Gram negativos no fermentadores en mayor proporción, seguido de fermentadores, Gram positivos y esporulados. Se logró la mayor eliminación de microorganismos por el protocolo de desinfección con glutaraldehído al 2%, seguido de hipoclorito de sodio al 0,5% y cloruro de benzalconio al 1%.


The present research evaluated the action of three disinfectants (glutaraldehyde, sodium hypochlorite and benzalconic chloride) in front of susceptible surfaces with more bacterial contamination in dental units of continuous use, comparing the bacterial population before and after the disinfection, of interest in health publishes in the area of Dentistry. Three surfaces were selected (it squirts triple, front of the seat, spittoon) by means of questionnaires to the personnel of the clinical dentistry of the University Antonio Nariño South Headquarters. The microorganisms found were similar for all dental units, with prevalence of Gram negative not fermentadors in greater proportion, followed by fermentadors, Gram positive and sporulade. There was the largest removal of microorganisms by the protocol of disinfection with glutaraldehyde to 2%, followed by sodium hipochloride to 0.5% and benzalconic chloride to 1%.


Asunto(s)
Antiinfecciosos , Bacterias , Contaminación de Equipos , Equipo Dental/microbiología , Medicina Oral
19.
Arq. bras. med. vet. zootec ; 59(3): 641-646, jun. 2007. ilus
Artículo en Portugués | LILACS | ID: lil-461140

RESUMEN

Em uma égua, submetida à laparotomia para correção de vólvulo do cólon maior, realizou-se enterectomia próximo ao ligamento cecocólico seguida de enteroanastomose término-terminal. Nas primeiras 24 horas do período pós-operatório, houve piora dos sinais clínicos, com ocorrência de dor, refluxo enterogástrico e agravamento do quadro de endotoxemia. Frente ao prognóstico desfavorável, optou-se pela eutanásia. Durante a necropsia, não foram constatadas falhas na enteroanastomose ou sinais de peritonite séptica. Observou-se encarceramento de uma alça de jejuno, que se apresentava justaposta à extremidade livre da prega cecocólica e comprimida entre o corpo do ceco e o cólon ventral direito remanescente, caracterizando obstrução do tipo estrangulada. Esse achado foi compatível com o agravamento do quadro clínico observado no pós-operatório. Essa ocorrência sugere a necessidade de uma adaptação na técnica de ressecção do cólon maior, de forma a reduzir o espaço cecocólico e evitar um possível encarceramento de alças de intestino delgado.


A mare subjected to laparotomy to treat a large colon volvulus had the large colon transected close to the cecocolic ligament followed by anastomosis using end-to-end technique. Despite intensive care, worsening of the clinical signs occurred during the first 24 hours after surgery including pain, enterogastric reflux and grievance of the endotoxemia symptoms. Euthanasia was performed. During necropsy, no signs of failure of the anastomosis and peritonitis were found but a strangulated segment of jejunum was observed adjacent to the cecocolic fold and compressed by the body of the cecum and the reminiscent rigth ventral colon. This finding was associated with the worsening of the clinical signs during the post-operative period. This report indicates that an adaptation in the large colon resection technique reducing the cecocolic space may be beneficial in avoiding such complication.


Asunto(s)
Animales , Complicaciones Posoperatorias/veterinaria , Caballos , Laparotomía/métodos , Vólvulo Intestinal/cirugía , Vólvulo Intestinal/veterinaria , Colon Ascendente/cirugía , Yeyuno/lesiones
20.
Eye (Lond) ; 21(1): 16-22, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16311523

RESUMEN

AIMS: To compare retinal nerve fibre layer (RNFL) measurements were carried out with two different versions of an optical coherence tomography device in patients with band atrophy (BA) of the optic nerve and in normal controls. METHODS: The RNFL of 36 eyes (18 with BA and 18 normals) was measured using an earlier version of an optical coherence tomography device (OCT-1). The measurements were repeated using a later version of the same equipment (OCT-3), and the two sets of measurements were compared. RESULTS: Using OCT-1, the peripapillary RNFL thickness (mean+/-SD, in microm) in eyes with BA measured 80.42+/-6.94, 99.81+/-14.00, 61.69+/-13.02, 101.70+/-12.54, and 57.36+/-16.52 corresponding to the total RNFL average, superior, temporal, inferior, and nasal quadrants, respectively. Using OCT-3, the corresponding measurements were 63.11+/-6.76, 81.22+/-13.34, 39.50+/-8.27, 86.72+/-15.16, and 45.05+/-8.03. Each of these measurements was significantly smaller with OCT-3 than with OCT-1. In normal eyes, RNFL average and temporal quadrant OCT-3 values were significantly smaller than OCT-1 values, but there was no significant difference in measurements from the superior, inferior, and nasal quadrant. CONCLUSIONS: RNFL measurements were smaller with OCT-3 than with OCT-1 for almost all parameters in eyes with BA and in the global average and temporal quadrant measurements in normal eyes. Investigators should be aware of this fact when comparing old RNFL measurement with values obtained with later versions of the equipment.


Asunto(s)
Fibras Nerviosas/patología , Atrofia Óptica/patología , Retina/patología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica/instrumentación , Tomografía de Coherencia Óptica/métodos
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