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1.
Pediatr Obes ; 13(12): 794-802, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30207079

RESUMEN

BACKGROUND: Exercise training improves cardiometabolic outcomes in 'mean terms', but little information is available in children about the impact of the frequency/week and the wide inter-individual variability to exercise training reported in adults. OBJECTIVES: We compared the effects of resistance training (RT) and high-intensity interval training (HIT), and 'high' and 'low' frequency of training/week, for their effectiveness in decreasing insulin resistance (IR) levels in schoolchildren. A second aim was to decscribe and compare the prevalence of non-responders (NRs) between the different frequencies of training protocol. METHODS: Fifty-three schoolchildren with IR were randomly assigned into four groups: RT at high frequency (three times/week), HIT at high frequency, RT at a low frequency (two times/week) and HIT at low frequency. The intervention lasted 6 weeks. Blood samples and body composition, blood pressure and performance measurements were taken before and after the intervention. RESULTS: The prevalence of NRs was similar between the RTHF and HITHF (25.0% vs. 25.0%, P > 0.05) and RTLF and HITLF groups (20.0% vs. 46.6%, P = 0.174) for decreasing homeostasis model assessment of IR. However, significant differences in the prevalence of NRs were detected between RTHF and HITHF groups in fasting glucose (FGL) (18.7% vs. 58.3%, P < 0.031). CONCLUSIONS: Both RT and HIT improves the glucose control parameters in schoolchildren over 6 weeks, but only HIT is independent of a high or low frequency of training/week. The prevalence of NRs is similar for decreasing homeostasis model assessment of IR comparing each exercise mode in high vs. low frequency/week. However, both high- and low-frequency RT and HIT results in differences in the prevalence of NRs for FGL and other cardiometabolic and performance outcomes.


Asunto(s)
Glucemia/fisiología , Terapia por Ejercicio/métodos , Ejercicio Físico/fisiología , Resistencia a la Insulina/fisiología , Adolescente , Presión Sanguínea/fisiología , Composición Corporal/fisiología , Niño , Humanos , Prevalencia
3.
Int J Biometeorol ; 62(4): 493-500, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28986694

RESUMEN

This study aimed to investigate the effect of heat stress and month of birth on growth performance, pelleted starter intake, and stress-related hormones in Holstein calves. Birth weight and growth records, representing 4735 Holstein calves from a large commercial dairy herd in northern Mexico (25° N; 22.3 °C mean annual temperature) from 2013 to 2015, were analyzed. Temperature-humidity index (THI) at calving, season of birth, and month of birth were the independent variables, whereas growth traits were the dependent variables. Increased THI at birth from < 65 to > 85 units was associated with a decrease in birth weight from 39.3 to 38.7 kg. Calves subjected to high THI (> 75 units) at calving showed lesser (P < 0.01) pre-weaning gains (405 ± 97 g/calf/day), whereas those calves born with THI < 70 units presented the highest gains (466 ± 112 g/calf/day). Birth during the fall months reduced (P < 0.01) weaning weight by about 5 kg compared with winter months. Also, the pre-weaning average daily gain for calves born in the fall was about 70 g less (P < 0.01) than calves delivered in winter months. Plasma triiodothyronine and tetraiodothyronine levels were lower (1.02 ± 0.21 and 48 ± 7.9 ng/mL, respectively; P < 0.01) in summer and highest in winter (1.64 ± 0.48 and 66 ± 11 ng/mL, respectively). Mean plasma cortisol concentration was higher in heat-stressed calves born in summer (59 ± 40 ng/mL) than calves born in winter (20 ± 28 ng/mL). Pelleted starter intake 1 week before weaning was lowest (P < 0.01) in the fall (0.82 ± 0.26 kg/calf/day; mean ± SD) and highest in spring (1.26 ± 0.43 kg/calf/day). It was concluded that in this particular environment, heat stress affects birth weight and growth rate of Holstein calves. Thus, environmental management of the newborn calf during hot spring and summer months is warranted to optimize pelleted starter intake and calf growth rates.


Asunto(s)
Enfermedades de los Bovinos , Trastornos de Estrés por Calor , Alimentación Animal , Animales , Peso Corporal , Bovinos/sangre , Bovinos/crecimiento & desarrollo , Enfermedades de los Bovinos/sangre , Ingestión de Alimentos , Femenino , Trastornos de Estrés por Calor/sangre , Trastornos de Estrés por Calor/veterinaria , Humedad , Hidrocortisona/sangre , Temperatura , Destete
4.
J Econ Entomol ; 110(4): 1465-1475, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28499035

RESUMEN

This study describes four multiple nucleocapsid nucleopolyhedrovirus isolates recovered from infected larvae of beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), on crops in two different geographical regions of Mexico. Molecular and biological characterization was compared with characterized S. exigua multiple nucleopolyhedrovirus (SeMNPV) isolates from the United States (SeUS1 and SeUS2) and Spain (SeSP2). Restriction endonuclease analysis of viral DNA confirmed that all Mexican isolates were SeMNPV isolates, but molecular differences between the Mexican and the reference isolates were detected using PCR combined with restriction fragment length polymorphism (RFLP). Amplification of the variable region V01 combined with RFLP distinguished the two Mexican isolates, SeSLP6 and SeSIN6. BglII digestions showed that the majority of the isolates contained submolar bands, indicating the presence of genetic heterogeneity. Amplification of the variable regions V04 and V05 distinguished between American and the Spanish isolates. Biological characterization was performed against two laboratory colonies of S. exigua, one from Mexico, and another from Switzerland. Insects from the Mexican colony were less susceptible to infection than insects from Se-Swiss colony. In the Se-Mex colony, SeSP2 was the most pathogenic isolate followed by SeSIN6, although their virulence was similar to most of the isolates tested. In Se-Swiss colony, similar LD50 values were observed for the five isolates, although the virulence was higher for the SeSLP6 isolate, which also had the highest OB (occlusion body) yield. We conclude that the Mexican isolates SeSIN6 and SeSLP6 possess insecticidal traits of value for the development of biopesticides for the control of populations of S. exigua.


Asunto(s)
ADN Viral/genética , Nucleopoliedrovirus/fisiología , Control Biológico de Vectores , Spodoptera/virología , Animales , Larva/crecimiento & desarrollo , Larva/virología , México , Nucleopoliedrovirus/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Spodoptera/crecimiento & desarrollo
5.
Parkinsons Dis ; 2017: 9641392, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28280646

RESUMEN

Parkinson's disease (PD) is a neurodegenerative condition, which compromises the motor functions and causes the alteration of some executive brain functions. The presence of changes in cognitive symptoms in PD could be due to the procedure of deep brain stimulation (DBS). We searched in several databases for studies that compared performance in executive function tests before and after the DBS procedure in PE and then performed a meta-analysis. After the initial search, there were 15 articles that specifically evaluated the functions of verbal fluency, working memory, cognitive flexibility, abstract thinking, and inhibition. It was found that there were differences in the evaluation of the cognitive functions in terms of the protocols, which generated heterogeneity in the results of the meta-analysis. Likewise, a tendency to diminish functions like verbal fluency and inhibition was found, being this consistent with similar studies. In the other functions evaluated, no difference was found between pre- and postsurgery scores. Monitoring of this type of function is recommended after the procedure.

6.
Braz J Med Biol Res ; 49(4): e5106, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27007653

RESUMEN

After a traumatic injury to the central nervous system, the distal stumps of axons undergo Wallerian degeneration (WD), an event that comprises cytoskeleton and myelin breakdown, astrocytic gliosis, and overexpression of proteins that inhibit axonal regrowth. By contrast, injured neuronal cell bodies show features characteristic of attempts to initiate the regenerative process of elongating their axons. The main molecular event that leads to WD is an increase in the intracellular calcium concentration, which activates calpains, calcium-dependent proteases that degrade cytoskeleton proteins. The aim of our study was to investigate whether preventing axonal degeneration would impact the survival of retinal ganglion cells (RGCs) after crushing the optic nerve. We observed that male Wistar rats (weighing 200-400 g; n=18) treated with an exogenous calpain inhibitor (20 mM) administered via direct application of the inhibitor embedded within the copolymer resin Evlax immediately following optic nerve crush showed a delay in the onset of WD. This delayed onset was characterized by a decrease in the number of degenerated fibers (P<0.05) and an increase in the number of preserved fibers (P<0.05) 4 days after injury. Additionally, most preserved fibers showed a normal G-ratio. These results indicated that calpain inhibition prevented the degeneration of optic nerve fibers, rescuing axons from the process of axonal degeneration. However, analysis of retinal ganglion cell survival demonstrated no difference between the calpain inhibitor- and vehicle-treated groups, suggesting that although the calpain inhibitor prevented axonal degeneration, it had no effect on RGC survival after optic nerve damage.


Asunto(s)
Axones/efectos de los fármacos , Glicoproteínas/farmacología , Traumatismos del Nervio Óptico/tratamiento farmacológico , Polivinilos/farmacología , Células Ganglionares de la Retina/efectos de los fármacos , Degeneración Walleriana/tratamiento farmacológico , Animales , Axones/patología , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Inmunohistoquímica , Masculino , Microscopía Electrónica de Transmisión , Compresión Nerviosa , Traumatismos del Nervio Óptico/patología , Ratas Wistar , Células Ganglionares de la Retina/patología , Factores de Tiempo , Resultado del Tratamiento , Degeneración Walleriana/patología
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;49(4): e5106, 2016. graf
Artículo en Inglés | LILACS | ID: biblio-951668

RESUMEN

After a traumatic injury to the central nervous system, the distal stumps of axons undergo Wallerian degeneration (WD), an event that comprises cytoskeleton and myelin breakdown, astrocytic gliosis, and overexpression of proteins that inhibit axonal regrowth. By contrast, injured neuronal cell bodies show features characteristic of attempts to initiate the regenerative process of elongating their axons. The main molecular event that leads to WD is an increase in the intracellular calcium concentration, which activates calpains, calcium-dependent proteases that degrade cytoskeleton proteins. The aim of our study was to investigate whether preventing axonal degeneration would impact the survival of retinal ganglion cells (RGCs) after crushing the optic nerve. We observed that male Wistar rats (weighing 200-400 g; n=18) treated with an exogenous calpain inhibitor (20 mM) administered via direct application of the inhibitor embedded within the copolymer resin Evlax immediately following optic nerve crush showed a delay in the onset of WD. This delayed onset was characterized by a decrease in the number of degenerated fibers (P<0.05) and an increase in the number of preserved fibers (P<0.05) 4 days after injury. Additionally, most preserved fibers showed a normal G-ratio. These results indicated that calpain inhibition prevented the degeneration of optic nerve fibers, rescuing axons from the process of axonal degeneration. However, analysis of retinal ganglion cell survival demonstrated no difference between the calpain inhibitor- and vehicle-treated groups, suggesting that although the calpain inhibitor prevented axonal degeneration, it had no effect on RGC survival after optic nerve damage.


Asunto(s)
Animales , Masculino , Polivinilos/farmacología , Células Ganglionares de la Retina/efectos de los fármacos , Axones/efectos de los fármacos , Degeneración Walleriana/tratamiento farmacológico , Glicoproteínas/farmacología , Traumatismos del Nervio Óptico/tratamiento farmacológico , Axones/patología , Inmunohistoquímica , Supervivencia Celular/efectos de los fármacos , Resultado del Tratamiento , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Ratas Wistar , Traumatismos del Nervio Óptico/patología , Microscopía Electrónica de Transmisión , Compresión Nerviosa
8.
J Anim Sci ; 92(11): 4823-32, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25349337

RESUMEN

Little is known about local Criollo pig genetic resources and relationships among the various populations. In this paper, genetic diversity and relationships among 17 Criollo pig populations from 11 American countries were assessed with 24 microsatellite markers. Heterozygosities, F-statistics, and genetic distances were estimated, and multivariate, genetic structure and admixture analyses were performed. The overall means for genetic variability parameters based on the 24 microsatellite markers were the following: mean number of alleles per locus of 6.25 ± 2.3; effective number of alleles per locus of 3.33 ± 1.56; allelic richness per locus of 4.61 ± 1.37; expected and observed heterozygosity of 0.62 ± 0.04 and 0.57 ± 0.02, respectively; within-population inbreeding coefficient of 0.089; and proportion of genetic variability accounted for by differences among breeds of 0.11 ± 0.01. Genetic differences were not significantly associated with the geographical location to which breeds were assigned or their country of origin. Still, the NeighborNet dendrogram depicted the clustering by geographic origin of several South American breeds (Criollo Boliviano, Criollo of northeastern Argentina wet, and Criollo of northeastern Argentina dry), but some unexpected results were also observed, such as the grouping of breeds from countries as distant as El Salvador, Mexico, Ecuador, and Cuba. The results of genetic structure and admixture analyses indicated that the most likely number of ancestral populations was 11, and most breeds clustered separately when this was the number of predefined populations, with the exception of some closely related breeds that shared the same cluster and others that were admixed. These results indicate that Criollo pigs represent important reservoirs of pig genetic diversity useful for local development as well as for the pig industry.


Asunto(s)
Cruzamiento/métodos , Repeticiones de Microsatélite/genética , Porcinos/genética , Alelos , Américas , Animales , Variación Genética/genética , Heterocigoto
9.
Genet Mol Res ; 12(2): 1119-31, 2013 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-23661437

RESUMEN

The Uruguayan Creole cattle population (N = 600) is located in a native habitat in south-east Uruguay. We analyzed its genetic diversity and compared it to other populations of American Creole cattle. A random sample of 64 animals was genotyped for a set of 17 microsatellite loci, and the D-loop hyper-variable region of mtDNA was sequenced for 28 calves of the same generation. We identified an average of 5.59 alleles per locus, with expected heterozygosities between 0.466 and 0.850 and an expected mean heterozygosity of 0.664. The polymorphic information content ranged from 0.360 to 0.820, and the global FIS index was 0.037. The D-loop analysis revealed three haplotypes (UY1, UY2 and UY3), belonging to the European matriline group, with a haplotype diversity of 0.532. The history of the population, changes in the effective population size, bottlenecks, and genetic drift are possible causes of the genetic variability patterns that we detected.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Repeticiones de Microsatélite/genética , Alelos , Animales , Cruzamiento , Bovinos , Evolución Molecular , Frecuencia de los Genes , Genética de Población , Haplotipos , Filogenia
10.
Neuroscience ; 230: 184-97, 2013 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-23103791

RESUMEN

Peripheral-nerve injuries are a common clinical problem and often result in long-term functional deficits. Reconstruction of peripheral-nerve defects is currently undertaken with nerve autografts. However, there is a limited availability of nerves that can be sacrificed and the functional recovery is never 100% satisfactory. We have previously shown that gene therapy with vascular endothelial growth factor (VEGF) significantly improved nerve regeneration, neuronal survival, and muscle activity. Our hypothesis is that granulocyte colony-stimulating factor (G-CSF) synergizes with VEGF to improve the functional outcome after sciatic nerve transection. The left sciatic nerves and the adjacent muscle groups of adult mice were exposed, and 50 or 100 µg (in 50 µl PBS) of VEGF and/or G-CSF genes was injected locally, just below the sciatic nerve, and transferred by electroporation. The sciatic nerves were transected and placed in an empty polycaprolactone (PCL) nerve guide, leaving a 3-mm gap to challenge nerve regeneration. After 6 weeks, the mice were perfused and the sciatic nerve, the dorsal root ganglion (DRG), the spinal cord and the gastrocnemius muscle were processed for light and transmission electron microscopy. Treated animals showed significant improvement in functional and histological analyses compared with the control group. However, the best results were obtained with the G-CSF+VEGF-treated animals: quantitative analysis of regenerated nerves showed a significant increase in the number of myelinated fibers and blood vessels, and the number of neurons in the DRG and motoneurons in the spinal cord was significantly higher. Motor function also showed that functional recovery occurred earlier in animals receiving G-CSF+VEGF-treatment. The gastrocnemius muscle showed an increase in weight and in the levels of creatine phosphokinase, suggesting an improvement of reinnervation and muscle activity. These results suggest that these two factors acted synergistically and optimized the nerve repair potential, improving regeneration after a transection lesion.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Regeneración Nerviosa/fisiología , Recuperación de la Función/fisiología , Neuropatía Ciática/terapia , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Análisis de Varianza , Animales , Creatina Quinasa/metabolismo , Modelos Animales de Enfermedad , Femenino , Ganglios Espinales/metabolismo , Ganglios Espinales/patología , Ganglios Espinales/ultraestructura , Factor Estimulante de Colonias de Granulocitos/genética , Humanos , Locomoción/genética , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Músculo Esquelético/ultraestructura , Regeneración Nerviosa/genética , Recuperación de la Función/genética , Neuropatía Ciática/patología , Médula Espinal/patología , Médula Espinal/ultraestructura , Trasplante , Factor A de Crecimiento Endotelial Vascular/genética
11.
Neurol Res ; 34(10): 937-43, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23146297

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease of unknown aetiology. Diagnosis is made through physical examination, electrophysiological findings, and by excluding other conditions. There is not a single biomarker that concludes the diagnosis. The aim of this study was to investigate differentially expressed proteins in cerebrospinal fluid (CSF) of ALS patients compared to control subjects, with the purpose to identify a panel of possible biomarkers for the disease. The differentially expressed spots/proteins were submitted to two-dimensional (2D) electrophoresis and recognized with matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry. Parkin-like and many iron and zinc binding were some of the proteins found in ALS CSF. Parkin is a ligase involved in ubiquitin-proteasome pathway and mutations in the parkin gene are the most common cause of recessive familial Parkinson's disease. Iron and zinc are involved with many important metabolic processes and are related to neurodegenerative disease. Common features of ALS comprise failure of the ubiquitin-proteasome system and increased levels of metal ions in the brain. Therefore, the identification of these proteins can be a significant step in ALS research. These and other identified proteins are discussed in this study.


Asunto(s)
Esclerosis Amiotrófica Lateral/líquido cefalorraquídeo , Esclerosis Amiotrófica Lateral/genética , Proteómica/métodos , Adulto , Anciano , Esclerosis Amiotrófica Lateral/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteómica/tendencias , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/tendencias
12.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(6): 488-496, June 2012. ilus
Artículo en Inglés | LILACS | ID: lil-622781

RESUMEN

We studied the effect of pulsed ultrasound therapy (UST) and antibothropic polyvalent antivenom (PAV) on the regeneration of mouse extensor digitorum longus muscle following damage by Bothrops jararacussu venom. Animals (Swiss male and female mice weighing 25.0 ± 5.0 g; 5 animals per group) received a perimuscular injection of venom (1 mg/kg) and treatment with UST was started 1 h later (1 min/day, 3 MHz, 0.3 W/cm², pulsed mode). Three and 28 days after injection, muscles were dissected and processed for light microscopy. The venom caused complete degeneration of muscle fibers. UST alone and combined with PAV (1.0 mL/kg) partially protected these fibers, whereas muscles receiving no treatment showed disorganized fascicules and fibers with reduced diameter. Treatment with UST and PAV decreased the effects of the venom on creatine kinase content and motor activity (approximately 75 and 48%, respectively). Sonication of the venom solution immediately before application decreased the in vivo and ex vivo myotoxic activities (approximately 60 and 50%, respectively). The present data show that UST counteracts some effects of B. jararacussu venom, causing structural and functional improvement of the regenerated muscle after venom injury.


Asunto(s)
Animales , Femenino , Masculino , Ratones , Antivenenos/farmacología , Bothrops , Venenos de Crotálidos/envenenamiento , Músculo Esquelético/efectos de los fármacos , Mordeduras de Serpientes/terapia , Terapia por Ultrasonido/métodos , Creatina Quinasa/metabolismo , Venenos de Crotálidos/administración & dosificación , Edema/inducido químicamente , Factores Inmunológicos/inmunología , Actividad Motora/efectos de los fármacos , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Necrosis , Prueba de Desempeño de Rotación con Aceleración Constante , Regeneración/efectos de los fármacos , Mordeduras de Serpientes/complicaciones
13.
Braz J Med Biol Res ; 45(6): 488-96, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22415117

RESUMEN

We studied the effect of pulsed ultrasound therapy (UST) and antibothropic polyvalent antivenom (PAV) on the regeneration of mouse extensor digitorum longus muscle following damage by Bothrops jararacussu venom. Animals (Swiss male and female mice weighing 25.0 ± 5.0 g; 5 animals per group) received a perimuscular injection of venom (1 mg/kg) and treatment with UST was started 1 h later (1 min/day, 3 MHz, 0.3 W/cm(2), pulsed mode). Three and 28 days after injection, muscles were dissected and processed for light microscopy. The venom caused complete degeneration of muscle fibers. UST alone and combined with PAV (1.0 mL/kg) partially protected these fibers, whereas muscles receiving no treatment showed disorganized fascicules and fibers with reduced diameter. Treatment with UST and PAV decreased the effects of the venom on creatine kinase content and motor activity (approximately 75 and 48%, respectively). Sonication of the venom solution immediately before application decreased the in vivo and ex vivo myotoxic activities (approximately 60 and 50%, respectively). The present data show that UST counteracts some effects of B. jararacussu venom, causing structural and functional improvement of the regenerated muscle after venom injury.


Asunto(s)
Antivenenos/farmacología , Bothrops , Venenos de Crotálidos/envenenamiento , Músculo Esquelético/efectos de los fármacos , Mordeduras de Serpientes/terapia , Terapia por Ultrasonido/métodos , Animales , Creatina Quinasa/metabolismo , Venenos de Crotálidos/administración & dosificación , Edema/inducido químicamente , Femenino , Factores Inmunológicos/inmunología , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Necrosis , Regeneración/efectos de los fármacos , Prueba de Desempeño de Rotación con Aceleración Constante , Mordeduras de Serpientes/complicaciones
14.
Neotrop Entomol ; 40(1): 129-37, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21437495

RESUMEN

The lethal and sublethal effects of the ecdysone agonist methoxyfenozide on the fall armyworm, Spodoptera frugiperda (J. E. Smith), were investigated by feeding a methoxyfenozide-treated diet to fifth instars until pupation in doses corresponding to the LC10 and LC25 for the compound. Larval mortality reached 8% and 26% in the low and high concentration groups, respectively, on the seventh day of the experiment. A progressive larval mortality of 12% for the LC10 and 60% for the LC25 was observed before pupation. Treated larvae exhibited lower pupal weights, higher pupal mortality, presence of deformed pupae, and more deformed adults than untreated larvae. The incorporation of methoxyfenozide into the diet had a significant effect on the timing of larval development. The development period for males and females was about seven days longer than the controls for both concentrations tested. In contrast, the compound affected neither pupae nor adult longevity. Finally, S. frugiperda adults that resulted from fifth instars treated with methoxyfenozide were not affected in their mean cumulative number of eggs laid per female (fecundity), nor percentages of eggs hatched (fertility), or the sex ratio. Our results suggest that the combination of lethal and sublethal effects of methoxyfenozide may have important implications for the population dynamics of the fall armyworm.


Asunto(s)
Hidrazinas/farmacología , Hormonas Juveniles/farmacología , Spodoptera/efectos de los fármacos , Spodoptera/fisiología , Animales , Femenino , Fertilidad/efectos de los fármacos , Hidrazinas/toxicidad , Hormonas Juveniles/toxicidad , Larva/efectos de los fármacos , Masculino , Control de Plagas , Spodoptera/crecimiento & desarrollo
15.
Mol Cell Endocrinol ; 337(1-2): 71-9, 2011 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-21315800

RESUMEN

The higher prevalence of thyroid disease in women suggests that estrogen (E2) might be involved in the pathophysiology of thyroid dysfunction. To approach the question of the effect of stromal cells in the modulation of thyroid epithelial cells activity, we established and characterized a homogeneous stromal cell population (TS7 cells) of rat thyroid gland. These fibroblastic cells synthesize the cytoskeleton proteins α-smooth muscle actin and vimentin, produce basement membrane components and express the cytokine transforming growth factor beta 1 (TGF-ß1). Here, we hypothesized that the effects of E2 on follicular thyroid cells are mediated by TGF-ß1 synthesis and secretion by stromal cells (paracrine action). Thus we investigated the effect of E2 on TGF-ß1 synthesis and its signaling pathway in TS7 cells. In addition, we analyzed the role of TGF-ß1 signaling pathway as mediator of TS7-PC CL3 thyroid epithelial cells interactions. We report that TS7 stromal cells expressed α and ß estrogen receptors (ERα and ERß). Further, both isoforms of TGF-ß1 receptors, TGFRI and TGFRII, were also identified in TS7 cells, suggesting that these cells might be a target for this cytokine in vitro. Treatment of TS7 cells with E2 induced both synthesis and secretion of TGF-ß1. This event was followed by phosphorylation of the transcription factor Smad2, a hallmark of TGF-ß1 pathway activation. Co-culture of PC CL3 cells onto TS7 cells monolayers yielded round aggregates of PC CL3 cells surrounded by TS7 cells. TS7 cells induced a decrease in iodide uptake by PC CL3 cells, probably by a mechanism involving TGF-ß1. Moreover, E2 affected synthesis and organization of the extracellular matrix (ECM) components, tenascin C and chondroitin sulfate, in these co-culture cells. Our results point to the TGF-ß1/Smad-2 signaling pathway as a putative target of estrogen actions on thyroid stromal cells and contribute to understanding the interplay between stromal and follicular cells in thyroid physiology.


Asunto(s)
Estradiol/metabolismo , Transducción de Señal , Células del Estroma/metabolismo , Glándula Tiroides/citología , Factor de Crecimiento Transformador beta1/genética , Animales , Forma de la Célula , Supervivencia Celular , Células Cultivadas , Técnicas de Cocultivo , Proteínas del Citoesqueleto/metabolismo , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Matriz Extracelular/metabolismo , Femenino , Ratas , Ratas Wistar , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Proteínas Smad/metabolismo , Glándula Tiroides/metabolismo , Transcripción Genética , Factor de Crecimiento Transformador beta1/metabolismo
16.
Neuropathol Appl Neurobiol ; 37(6): 600-12, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21208251

RESUMEN

AIMS: Recent studies have emphasized the beneficial effects of the vascular endothelial growth factor (VEGF) on neurone survival and Schwann cell proliferation. VEGF is a potent angiogenic factor, and angiogenesis has long been recognized as an important and necessary step during tissue repair. Here, we investigated the effects of VEGF on sciatic nerve regeneration. METHODS: Using light and electron microscopy, we evaluated sciatic nerve regeneration after transection and VEGF gene therapy. We examined the survival of the neurones in the dorsal root ganglia and in lumbar 4 segment of spinal cord. We also evaluated the functional recovery using the sciatic functional index and gastrocnemius muscle weight. In addition, we evaluated the VEGF expression by immunohistochemistry. RESULTS: Fluorescein isothiocyanate-dextran (FITC-dextran) fluorescence of nerves and muscles revealed intense staining in the VEGF-treated group. Quantitative analysis showed that the numbers of myelinated fibres and blood vessels were significantly higher in VEGF-treated animals. VEGF also increased the survival of neurone cell bodies in dorsal root ganglia and in spinal cord. The sciatic functional index and gastrocnemius muscle weight reached significantly higher values in VEGF-treated animals. CONCLUSION: We demonstrate a positive relationship between increased vascularization and enhanced nerve regeneration, indicating that VEGF administration can support and enhance the growth of regenerating nerve fibres, probably through a combination of angiogenic, neurotrophic and neuroprotective effects.


Asunto(s)
Terapia Genética/métodos , Regeneración Nerviosa/fisiología , Traumatismos de los Nervios Periféricos/terapia , Recuperación de la Función/fisiología , Nervio Ciático/fisiología , Factor A de Crecimiento Endotelial Vascular/genética , Animales , Femenino , Ratones , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Traumatismos de los Nervios Periféricos/fisiopatología
17.
Zoo Biol ; 30(4): 399-411, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20853411

RESUMEN

The African antelope Addax nasomaculatus is a rare mammal at high risk of extinction, with no more than 300 individuals in the wild and 1,700 captive animals distributed in zoos around the world. In this work, we combine genetic data and genealogical information to assess the structure and genetic diversity of a captive population located at Parque Lecocq Zoo (N=27), originated from only two founders. We amplified 39 microsatellites previously described in other Artiodactyls but new to this species. Seventeen markers were polymorphic, with 2-4 alleles per locus (mean=2.71). Mean expected heterozygosity (He) per locus was between 0.050 (marker ETH3) and 0.650 (marker D5S2), with a global He of 0.43. The mean inbreeding coefficient of the population computed from pedigree records of all registered individuals (N=53) was 0.222. The mean coancestry of the population was 0.298 and F(IS) index was -0.108. These results reflect the importance of an adequate breeding management on a severely bottlenecked captive population, which would benefit by the incorporation of unrelated individuals. Thanks to the successful amplification of a large number of microsatellites commonly used in domestic bovids, this study will provide useful information for the management of this population and serve as future reference for similar studies in other captive populations of this species.


Asunto(s)
Animales de Zoológico , Antílopes/genética , Crianza de Animales Domésticos , Animales , Conservación de los Recursos Naturales , Femenino , Variación Genética , Masculino , Repeticiones de Microsatélite , Linaje , Uruguay
18.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);62(5): 1191-1198, out. 2010. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-570479

RESUMEN

The population structure of the Murciano-Granadina breed was determined using 25 microsatellites from 266 goats of seven populations. The results of the genetic differentiation analysis showed that it is possible to differentiate the Murciana and Granadina populations even though a low F ST value (0.0432) had been obtained. Individuals could be assigned to their populations with a success rate of more than 80 percent. Bayesian-based clustering analysis of allele frequencies and multivariate analysis revealed that Murciana and Granadina populations were grouped in different clusters since K=3. The results demonstrate that Murciana and Granadina are still two different genetic groups included into Murciano-Granadina denomination. There is the opportunity to the genetically manage these populations, under a single herd-book but adding the necessary modifications to respect the conservation of the genetic diversity based on the use of multibreed models of genetic evaluation.


Determinou-se a estrutura da raça Murciano-Granadina, usando-se 25 microssatélites e 266 animais de sete populações. Os resultados da diferenciação genética mostram que é possível diferenciar populações de Murciana e Granadina, apesar dos baixos valores de F ST obtidos - 0.0432. Os indivíduos foram designados às suas populações com taxa de sucesso superior a 80 por cento. A análise bayesiana de agrupamento das frequências alélicas e a análise multivariada revelaram que as populações Murciana e Granadina foram agrupadas em diferentes clusters, uma vez que o melhor K obtido foi três. Os resultados demonstraram que Murciana e Granadina ainda são dois grupos genéticos distintos incluídos na denominação Murciano-Granadina. É possível manejar geneticamente essas populações dentro de um único livro de registro, porém adotando-se as modificações necessárias em relação à conservação e à diversidade genética, com base no uso de modelos de avaliação multirracial.


Asunto(s)
Animales , Cabras/genética , Variación Genética , Repeticiones de Microsatélite
19.
Arq. bras. med. vet. zootec ; 62(5): 1191-1198, Oct. 2010. ilus, graf, tab
Artículo en Inglés | VETINDEX | ID: vti-6008

RESUMEN

The population structure of the Murciano-Granadina breed was determined using 25 microsatellites from 266 goats of seven populations. The results of the genetic differentiation analysis showed that it is possible to differentiate the Murciana and Granadina populations even though a low F ST value (0.0432) had been obtained. Individuals could be assigned to their populations with a success rate of more than 80 percent. Bayesian-based clustering analysis of allele frequencies and multivariate analysis revealed that Murciana and Granadina populations were grouped in different clusters since K=3. The results demonstrate that Murciana and Granadina are still two different genetic groups included into Murciano-Granadina denomination. There is the opportunity to the genetically manage these populations, under a single herd-book but adding the necessary modifications to respect the conservation of the genetic diversity based on the use of multibreed models of genetic evaluation.(AU)


Determinou-se a estrutura da raça Murciano-Granadina, usando-se 25 microssatélites e 266 animais de sete populações. Os resultados da diferenciação genética mostram que é possível diferenciar populações de Murciana e Granadina, apesar dos baixos valores de F ST obtidos - 0.0432. Os indivíduos foram designados às suas populações com taxa de sucesso superior a 80 por cento. A análise bayesiana de agrupamento das frequências alélicas e a análise multivariada revelaram que as populações Murciana e Granadina foram agrupadas em diferentes clusters, uma vez que o melhor K obtido foi três. Os resultados demonstraram que Murciana e Granadina ainda são dois grupos genéticos distintos incluídos na denominação Murciano-Granadina. É possível manejar geneticamente essas populações dentro de um único livro de registro, porém adotando-se as modificações necessárias em relação à conservação e à diversidade genética, com base no uso de modelos de avaliação multirracial.(AU)


Asunto(s)
Animales , Cabras/genética , Variación Genética , Repeticiones de Microsatélite
20.
Int J STD AIDS ; 21(7): 466-71, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20852195

RESUMEN

We estimated the prevalence of hepatitis C (HCV) infection and associated risk factors in 750 individuals attending the Voluntary Counseling and Testing Center of Rio Grande (VCT/RG), in Southern Brazil, and identified viral genotypes. Demographic data and risk factors for HCV transmission were also collected and analysed. Anti-HCV antibody-positive individuals were tested for HCV-RNA and genotyped by sequencing the 5' untranslated region of the viral genome. Prevalence estimates of anti-HCV and HCV-RNA were 6% and 5.5%, respectively. We identified genotypes 1 (67%), 2 (2%) and 3 (31%); the latter was more prevalent than in other regions of Brazil. Anti-HCV prevalence in VCT/RG users was similar to previous reports. Age, previous blood transfusion, sexual orientation and injecting drug use were independent predictors of HCV infection. The presence of multiple risk factors was also associated with a higher risk for HCV infection. HCV genotype was not associated with any variable analysed in this study.


Asunto(s)
Hepacivirus/aislamiento & purificación , Hepatitis C/epidemiología , Regiones no Traducidas 5' , Adulto , Brasil/epidemiología , Femenino , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepacivirus/inmunología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Prevalencia , ARN Viral/genética , Factores de Riesgo
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