Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Zhonghua Yi Xue Za Zhi ; 101(9): 624-629, 2021 Mar 09.
Artículo en Chino | MEDLINE | ID: mdl-33685043

RESUMEN

Objective: To investigate the diagnostic value of apparent diffusion coefficient (ADC) histogram in quantifying moderate to severe neonatal hypoxic-ischemic encephalopathy (HIE). Methods: A total of 49 children with moderate to severe HIE admitted to the Children's Hospital Affiliated to Nanjing Medical University from July 2015 to September 2018 were retrospectively analyzed. Cranial magnetic resonance imaging (MRI) data of 31 full-term neonates without neurological symptoms and signs who visited the hospital during the same period were recruited as the control group. ImgJ software was used to delineate the whole brain area at the thalamus/basal ganglia level as the area of interest, and MRIcron software was used to obtain ADC histogram parameters. The differences of ADC histogram parameters between HIE group and control group were compared. The correlation between ADC histogram parameters and neonatal neurobehavioral neurological assessment (NBNA) in HIE group was analyzed. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficiency of each parameter. Results: The mean value, minimum value, maximum value, mode-value, variance, heterogeneity and 10%-90% ADC values of HIE group were all greater than those of the control group(634±65,310±36,1 683±18,711±87,66 928±921,5 907±204,477±50,513±53,542±56,568±59,591±61,625±92,661±97,709±105,811±119),the differences were statistically significant(all P<0.05), while mode-count of HIE group was smaller than that of the control group(272±22 to 395±83), and the difference was statistically significant (t=2.996,P<0.05). All the above parameters with statistical differences were correlated with NBNA score, among which mode-count was negatively correlated with NBNA score(r=-0.369,P<0.05), and the rest were positively correlated(all P<0.05). The area under the ROC curve (AUC) of variance had the highest diagnostic efficiency (0.881), followed by 90% ADC value and ADC maximum value. Conclusion: ADC histogram is helpful for the diagnosis of HIE, objectively and quantitatively reflecting the diffusion information of brain, and assessing the severity of HIE.


Asunto(s)
Hipoxia-Isquemia Encefálica , Encéfalo/diagnóstico por imagen , Niño , Imagen de Difusión por Resonancia Magnética , Humanos , Hipoxia-Isquemia Encefálica/diagnóstico por imagen , Recién Nacido , Curva ROC , Estudios Retrospectivos
2.
Animal ; 15(2): 100144, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33573949

RESUMEN

For the spring-calving beef herds, late gestation coincides with winter and early spring, when cows are dependent on feed supplements with low quality hay, which is hard to meet their nutrient requirements. However, the effects of deficiencies of metabolizable protein intake during late gestation on offspring beef quality are unclear. Wagyu cattle have excellent marbling, and insemination with Wagyu vs Angus semen is a practical option for beef producers to improve beef quality. To test, Angus cows (621 ±â€¯73 kg) were selected and randomly separated into two groups. Each group was inseminated with either Angus or Wagyu semen. During the last 90 days of gestation, cows in each group were further separated and received either a low protein diet (85% of the NRC metabolizable protein requirement), which was a low quality hay-based diet common in northwestern region of the U.S., or an adequate protein diet (108% NRC requirement). All progeny was managed together and harvested at a final BW of 576.5 ±â€¯16.6 kg. Wagyu-sired offspring had higher marbling scores and quality grades than Angus (P < 0.01). Protein supplementation did not affect Slice Shear Force (SSF) in either breeds (P = 0.60). However, Wagyu-sired cattle had lower SSF than Angus-sired (P < 0.01). In addition, Wagyu-sired cattle had higher intramuscular fat (P < 0.05) and total collagen content (P < 0.05), but Angus-sired had greater mature collagen cross-links, as shown by higher contents of Pyridinoline (P < 0.01) and Ehrlich Chromogen (P < 0.01). Consistently, the mRNA expression of enzymes catalyzing collagen cross-linking was higher in Angus-sired offspring, including Plod 1 (P < 0.05), Plod 2 (P = 0.08), and P4Hα 2 (P < 0.01). In conclusion, Wagyu-sired cattle had greater tenderness and marbling score compared to Angus-sired, which was associated with lower collagen cross-links. Feeding mature grass hay-based diet with relatively low protein content during late gestation had no major effect on beef quality of subsequent cattle.


Asunto(s)
Dieta con Restricción de Proteínas , Carne , Animales , Bovinos , Dieta con Restricción de Proteínas/veterinaria , Suplementos Dietéticos , Femenino , Carne/análisis , Embarazo , Estaciones del Año
3.
Zhonghua Yi Xue Za Zhi ; 100(3): 178-181, 2020 Jan 21.
Artículo en Chino | MEDLINE | ID: mdl-32008282

RESUMEN

Objective: To evaluate the classification of the types of pediatric posterior fossa brain tumors based on routine MRI (T(1)WI, T(2)WI and ADC) using wavelet transformation analysis of whole tumor. Methods: MRI images of medulloblastoma (n=59), ependymoma (n=13) and pilocytic astrocytoma (n=27) confirmed by pathology before treatments in Children's Hospital of Nanjing Medical University from January 2014 to February 2019 were enrolled in this retrospective study as well as the clinical data of age, gender and symptoms. Registration was performed among the three sequences and wavelet features of ROI were acquired. Afterwards, the top ten features were ranked and trained among groups by using random forest classifier. Finally, the results were compared and analyzed according to the classification. Results: The top ten contribution three sequences and wavelet features of ROI were acquired from the ADC sequence. The random forest classifier achieved 100% accuracy on training data and was validated best accuracy (86.8%) when combined of first and third wavelet features. The sensitivity was 100%, 94.8%, 76.9%, and the specificity was 97.6%, 88.0%, 98.8% respectively. Conclusions: Features based on wavelet transformation of ADC sequence of entire tumor can provide more quantitative information, which could provide help in the differential diagnosis of pediatric posterior fossa brain tumors. The optimum combination to distinguish three pediatric posterior fossa brain tumors is sixth and twelfth wavelet features of ADC sequence.


Asunto(s)
Astrocitoma/clasificación , Neoplasias Cerebelosas/patología , Neoplasias Infratentoriales/patología , Imagen por Resonancia Magnética/métodos , Meduloblastoma/clasificación , Astrocitoma/patología , Neoplasias Encefálicas/patología , Niño , Humanos , Meduloblastoma/patología , Estudios Retrospectivos
5.
Zhonghua Yi Xue Za Zhi ; 98(39): 3162-3165, 2018 Oct 23.
Artículo en Chino | MEDLINE | ID: mdl-30392275

RESUMEN

Objective: To evaluate the value of apparent diffusion coefficient (ADC) histogram in neonatal brain alteration with congenital heart disease (CHD). Methods: MRIs of 60 neonates with CHD confirmed by echocardiography were retrospectively analyzed in Children's Hospital of Nanjing Medical University from January 2012 to December 2016.Twenty-two MRIs of neonates with mild pneumonia or scalp hematoma who were suspicious of brain disease but normal MRI findings were enrolled as normal control.MRIcron and ImgJ softwares were used to acquire ADC histogram.The correlation between the gestational age and ADC histogram values were calculated respectively.Then t-test was used to analyze the differences of the histogram values and the diagnostic efficacy of different parameters was analyzed using the receiver operating characteristic curve. Results: The ADC values were significantly correlated with the gestational age (P<0.05). The 70th-90th ADC, skewness, kurtosis and variance were statistically significant (P<0.05). The area under the curve of the 90th ADC value was the largest at 0.698. Conclusions: The ADC histogram can quantify and objectively provide more diffusion information of brain tissue. It is a rapid and feasible quantitative method to identify brain changes in neonates with CHD.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Interpretación de Imagen Asistida por Computador , Encéfalo , Niño , Cardiopatías , Humanos , Recién Nacido , Estudios Retrospectivos
6.
Animal ; : 1-7, 2018 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-29467043

RESUMEN

Protocols designed for the adipogenic differentiation of human and mouse cells are commonly used for inducing the adipogenesis of bovine stromal vascular cells. However, likely due to metabolic differences between ruminant and non-ruminant animals, these methods result in only few cells undergoing complete adipogenesis with minimal lipid droplet accumulation. Here, we discuss the development of an adipogenic differentiation protocol for bovine primary cells through a three-dimensional spheroid culture. Stromal vascular cells derived from bovine intramuscular fat were isolated and stored in liquid nitrogen before culturing. Cells were cultured in hanging drops for 3 days to allow for the formation of spherical structures. The spheroids were then transferred to cell culture plates with endothelial basal medium-2 for 3 days and in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with a standard adipogenic cocktail for 3 additional days, which were then allowed to fully differentiate for 3 days in DMEM supplemented with insulin. Compared with conventional two-dimensional culture, cells in a three-dimensional spheroid culture system had higher adipogenic gene expression and consequently contained more adipocytes with larger lipid droplets. In addition, endothelial induction of spheroids prior to adipogenic differentiation is essential for efficient induction of adipogenesis of bovine stromal vascular cells, mimicking in vivo adipose development. In summary, the newly developed three-dimensional spheroid culture method is an efficient way to induce adipogenic differentiation and study adipose development of cells derived from ruminant animals, which also can be used for studying the role of angiogenesis in adipose development.

7.
Nat Commun ; 8: 14552, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28211517

RESUMEN

An energy gap can be opened in the spectrum of graphene reaching values as large as 0.2 eV in the case of bilayers. However, such gaps rarely lead to the highly insulating state expected at low temperatures. This long-standing puzzle is usually explained by charge inhomogeneity. Here we revisit the issue by investigating proximity-induced superconductivity in gapped graphene and comparing normal-state measurements in the Hall bar and Corbino geometries. We find that the supercurrent at the charge neutrality point in gapped graphene propagates along narrow channels near the edges. This observation is corroborated by using the edgeless Corbino geometry in which case resistivity at the neutrality point increases exponentially with increasing the gap, as expected for an ordinary semiconductor. In contrast, resistivity in the Hall bar geometry saturates to values of about a few resistance quanta. We attribute the metallic-like edge conductance to a nontrivial topology of gapped Dirac spectra.

8.
Phys Rev Lett ; 116(18): 186603, 2016 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-27203338

RESUMEN

We observe a series of sharp resonant features in the differential conductance of graphene-hexagonal boron nitride-graphene tunnel transistors over a wide range of bias voltages between 10 and 200 mV. We attribute them to electron tunneling assisted by the emission of phonons of well-defined energy. The bias voltages at which they occur are insensitive to the applied gate voltage and hence independent of the carrier densities in the graphene electrodes, so plasmonic effects can be ruled out. The phonon energies corresponding to the resonances are compared with the lattice dispersion curves of graphene-boron nitride heterostructures and are close to peaks in the single phonon density of states.

9.
Int J Food Microbiol ; 229: 24-32, 2016 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-27099982

RESUMEN

Non-O157 Shiga toxin producing Escherichia coli (STECs) have become a growing concern to the food industry. Grape seed extract (GSE), a byproduct of wine industry, is abundant in polyphenols that are known to be beneficial to health. The objective of this study was to evaluate the effect of GSE on the growth, quorum sensing, and virulence factors of Centers for Disease Control and Prevention (CDC) "top-six" non-O157 STECs. Minimal inhibitory concentration (MIC) of GSE was 2mg/ml against E. coli O26:H11, and 4mg/ml against the other non-O157 STECs tested. Minimal bactericidal concentration (MBC) was the same as MIC for all six non-O157 STECs tested. At 5×10(5)CFU/ml inoculation level, 4mg/ml GSE effectively inhibited the growth of all tested strains, while 0.25-2mg/ml GSE delayed bacterial growth. At a higher inoculation level (1×10(7)CFU/ml), GSE had less efficacy against the growth of the selected six non-O157 STECs. Its impact on bacterial virulence was then assessed at this inoculation level. Autoinducer-2 (AI-2) is a universal signal molecule mediating quorum sensing (QS). GSE at concentration as low as 0.5mg/ml dramatically reduced AI-2 production of all non-O157 STECs tested, with the inhibitory effect proportional to GSE levels. Consistent with diminished QS, GSE at concentration of 0.125mg/ml caused marked reduction of swimming motility of all motile non-O157 STECs tested. In agreement, GSE treatment reduced the production of flagella protein FliC and its regulator FliA in E. coli O103:H2 and E. coli O111:H2. Furthermore, 4mg/ml GSE inhibited the production of Shiga toxin, a major virulence factor, in E. coli O103:H2 and E. coli O111:H2. In summary, GSE inhibits the growth of "top-six" non-O157 STECs at the population level relevant to food contamination. At higher initial population, GSE suppresses QS with concomitant decrease in motility, flagella protein expression and Shiga toxin production. Thus, GSE has the potential to be used in food industry to control non-O157 STEC.


Asunto(s)
Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Extracto de Semillas de Uva/farmacología , Percepción de Quorum/efectos de los fármacos , Escherichia coli Shiga-Toxigénica/efectos de los fármacos , Factores de Virulencia/genética , Antibacterianos/farmacología , Toxina Shiga/genética , Escherichia coli Shiga-Toxigénica/crecimiento & desarrollo
10.
Nat Commun ; 7: 10800, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26960435

RESUMEN

Microelectromechanical systems, which can be moved or rotated with nanometre precision, already find applications in such fields as radio-frequency electronics, micro-attenuators, sensors and many others. Especially interesting are those which allow fine control over the motion on the atomic scale because of self-alignment mechanisms and forces acting on the atomic level. Such machines can produce well-controlled movements as a reaction to small changes of the external parameters. Here we demonstrate that, for the system of graphene on hexagonal boron nitride, the interplay between the van der Waals and elastic energies results in graphene mechanically self-rotating towards the hexagonal boron nitride crystallographic directions. Such rotation is macroscopic (for graphene flakes of tens of micrometres the tangential movement can be on hundreds of nanometres) and can be used for reproducible manufacturing of aligned van der Waals heterostructures.


Asunto(s)
Compuestos de Boro/química , Grafito/química , Nanoestructuras/química , Cristalización , Elasticidad , Microscopía de Fuerza Atómica , Nanoestructuras/ultraestructura , Rotación , Termodinámica
11.
Animal ; 10(1): 75-81, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26350682

RESUMEN

The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first diverge into either myogenic or non-myogenic lineages; non-myogenic mesenchymal progenitors then develop into the stromal-vascular fraction of skeletal muscle wherein adipocytes, fibroblasts and derived mesenchymal progenitors reside. Because non-myogenic mesenchymal progenitors mainly undergo adipogenic or fibrogenic differentiation during muscle development, strengthening progenitor proliferation enhances the potential for both intramuscular adipogenesis and fibrogenesis, leading to the elevation of both marbling and connective tissue content in the resulting meat product. Furthermore, given the bipotent developmental potential of progenitor cells, enhancing their conversion to adipogenesis reduces fibrogenesis, which likely results in the overall improvement of marbling (more intramuscular adipocytes) and tenderness (less connective tissue) of meat. Fibrogenesis is mainly regulated by the transforming growth factor (TGF) ß signaling pathway and its regulatory cascade. In addition, extracellular matrix, a part of the intramuscular connective tissue, provides a niche environment for regulating myogenic differentiation of satellite cells and muscle growth. Despite rapid progress, many questions remain in the role of extracellular matrix on muscle development, and factors determining the early differentiation of myogenic, adipogenic and fibrogenic cells, which warrant further studies.


Asunto(s)
Tejido Conectivo/fisiología , Carne/normas , Células Madre Mesenquimatosas/metabolismo , Desarrollo de Músculos , Adipocitos/citología , Adipogénesis/fisiología , Animales , Diferenciación Celular , Tejido Conectivo/crecimiento & desarrollo , Femenino , Músculo Esquelético/crecimiento & desarrollo , Embarazo
12.
J Anim Sci ; 94(12): 5028-5041, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28046140

RESUMEN

It has been shown that hematological traits can act as important indicators of immune function in both humans and livestock. T lymphocytes are key components of the adaptive immune system, playing a critical role in immune response. To identify genomic regions affecting hematological traits and T lymphocyte subpopulations, we performed both a SNP-based genomewide association study (GWAS) and a haplotype analysis for 20 hematological traits and 8 T cell subpopulations at 3 different time points (d 20, 33, and 35) in a Duroc × Erhualian F intercross population. Bonferroni correction was used to calculate the threshold -values for suggestive and 5% genomewide significance levels. In total, for SNP-based GWAS, we detected 96 significant SNP, including 15 genomewide-significant SNP, associated with 23 hematological traits and 234 significant SNP, including 27 genomewide-significant SNP, associated with 8 T cell subpopulations. Meanwhile, we identified 563 significant SNP, including 7 genomewide-significant SNP, associated with 5 hematological traits and 2,407 significant SNP, including 1,261 genomewide-significant SNP, associated with 8 T cell subpopulations by haplotype analysis. Among the significant regions detected, we propose both the () gene and the () gene on SSC3 as plausible candidate genes associated with CD/CD T lymphocytes at d 20. The findings provide insights into the basis of molecular mechanisms that are involved with immune response in the domestic pig and would aid further identification of causative mutations.


Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Porcinos/genética , Animales , Femenino , Estudio de Asociación del Genoma Completo , Genómica , Haplotipos/genética , Hematología , Subgrupos Linfocitarios , Masculino , Fenotipo , Sitios de Carácter Cuantitativo/genética , Sus scrofa/genética , Porcinos/fisiología
13.
J Anim Sci ; 93(3): 1015-24, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26020879

RESUMEN

Japanese Wagyu cattle are well known for their extremely high marbling and lower subcutaneous adipose tissue compared with Angus cattle. However, mechanisms for differences in adipose deposition are unknown. The objective of this paper was to evaluate breed differences in the structure of subcutaneous adipose tissue, adipogenesis, and mitogenesis of stromal vascular (SV) cells between Wagyu and Angus cattle. Subcutaneous biopsy samples were obtained from 5 Wagyu (BW = 302 ± 9 kg) and 5 Angus (BW = 398 ± 12 kg) heifers at 12 mo of age, and samples were divided into 3 pieces for histological examination, biochemical analysis, and harvest of SV cells. Adipogenesis of SV cells was assessed by the expression of adipogenic markers and Oil Red-O staining, while mitogenesis was evaluated by an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium dromide) test, phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (PKB; AKT). Based on histological analysis, Wagyu had larger adipocytes compared with Angus. At the tissue level, protein expression of peroxisome proliferator-activated receptor γ (PPARG) in Wagyu was much lower compared with that of Angus. Similarly, a lower mRNA expression of PPARG was found in Wagyu SV cells. No significant difference was observed for the zinc finger protein 423 (ZNF423) expression between Wagyu and Angus. As assessed by Oil Red-O staining, Wagyu SV cells possessed a notable trend of lower adipogenic capability. Interestingly, higher mitogenic ability was discovered in Wagyu SV cells, which was associated with an elevated phosphorylation of ERK1/2. There was no difference in AKT phosphorylation of SV cells between Wagyu and Angus. Moreover, exogenous fibroblast growth factor 2 (FGF2) enhanced mitogenesis and ERK1/2 phosphorylation of SV cells to a greater degree in Angus compared with that in Wagyu. Expression of transforming growth factor ß 3 (TGFB3) and bone morphogenetic protein 2 (BMP2) in Wagyu SV cells was lower than that of Angus, providing potential clues for breed differences on proliferation of SV cells in these two cattle breeds. The results of this study suggest that subcutaneous adipose-derived SV cells of Wagyu possess a lower trend of adipogenesis but higher mitogenesis compared with those of Angus.


Asunto(s)
Adipogénesis/fisiología , Cruzamiento , Bovinos/genética , Mitosis/fisiología , Células del Estroma/citología , Grasa Subcutánea/irrigación sanguínea , Adipocitos/citología , Adipocitos/metabolismo , Animales , Biopsia , Proliferación Celular/fisiología , Células Cultivadas , Femenino , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , PPAR gamma/metabolismo , Células del Estroma/metabolismo , Grasa Subcutánea/metabolismo , Grasa Subcutánea/patología , Factor de Crecimiento Transformador beta3/metabolismo
14.
J Appl Microbiol ; 118(6): 1333-44, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25801786

RESUMEN

AIMS: Currently, there is no direct method for detecting Clostridium thermocellum in the insoluble medium. In this study, a quantitative real-time PCR assay was developed for the direct growth detection of C. thermocellum at the single-cell level in lignocellulosic biomasses. METHODS AND RESULTS: The assay targeted the cipA gene and was able to distinguish C. thermocellum from other species with good reproducibility which quantitative detection limit was 10 cell equivalents (CE) per reaction. OD600-based counting and qPCR quantification of C. thermocellum cultured in soluble medium were compared and an excellent consistency was revealed, indicating the appropriateness of the developed qPCR method. Analysis based on yellow affinity substrate and fermentation products may incorrectly estimate its population. CONCLUSIONS: The developed assay can serve as a specific, sensitive and reproducible method for the detection of C. thermocellum in lignocellulosic biomass at the single-cell level. SIGNIFICANCE AND IMPACT OF THE STUDY: With the ability to rapidly detect C. thermocellum, this method will contribute substantially to the understanding of the lignocellulosic biomass degradation mechanism. Moreover, it can also be applied to detect C. thermocellum growth in certain co-culture system for the understanding of the metabolic interactions.


Asunto(s)
Clostridium thermocellum/crecimiento & desarrollo , Lignina/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Proteínas Bacterianas/genética , Biomasa , Clostridium thermocellum/genética , Clostridium thermocellum/metabolismo , Fermentación , Datos de Secuencia Molecular , Reproducibilidad de los Resultados
15.
Nat Nanotechnol ; 9(10): 808-13, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25194946

RESUMEN

Recent developments in the technology of van der Waals heterostructures made from two-dimensional atomic crystals have already led to the observation of new physical phenomena, such as the metal-insulator transition and Coulomb drag, and to the realization of functional devices, such as tunnel diodes, tunnel transistors and photovoltaic sensors. An unprecedented degree of control of the electronic properties is available not only by means of the selection of materials in the stack, but also through the additional fine-tuning achievable by adjusting the built-in strain and relative orientation of the component layers. Here we demonstrate how careful alignment of the crystallographic orientation of two graphene electrodes separated by a layer of hexagonal boron nitride in a transistor device can achieve resonant tunnelling with conservation of electron energy, momentum and, potentially, chirality. We show how the resonance peak and negative differential conductance in the device characteristics induce a tunable radiofrequency oscillatory current that has potential for future high-frequency technology.

16.
J Anim Sci ; 92(5): 1840-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24243902

RESUMEN

Obesity in pregnant women is a growing public health concern that negatively affects fetal development and has long-term impacts on offspring health. The placenta plays an essential role in nutrient transport to the fetus and supports fetal growth and development. Maternal obesity (MO) induces an exacerbated proinflammatory milieu in the placenta providing an inflammatory environment for fetuses. The gut is one of the largest immune organs and mainly develops during the fetal stage. Maternal obesity and the corresponding inflammatory uteroplacental environment affect gut development, incurring inflammatory responses in the fetal intestine that further prime or program the offspring gut to enhance inflammation and impair intestinal barrier integrity. This review summarizes the impact of MO on inflammatory responses in placenta and fetal intestine and the long-term effects on offspring intestinal health. Because "leaky gut" is one of the main etiological factors for a number of common diseases, including inflammatory bowel diseases, type I diabetes, and related autoimmune diseases, the adverse effect of MO on the overall health of progeny is further discussed.


Asunto(s)
Inflamación/etiología , Intestinos/patología , Obesidad/complicaciones , Enfermedades Placentarias/etiología , Complicaciones del Embarazo/metabolismo , Congresos como Asunto , Femenino , Humanos , Inflamación/metabolismo , Inflamación/patología , Obesidad/metabolismo , Enfermedades Placentarias/metabolismo , Embarazo
17.
J Anim Sci ; 91(3): 1419-27, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23100595

RESUMEN

Beef cattle are raised for their lean tissue, and excessive fat accumulation accounts for large amounts of waste. On the other hand, intramuscular fat or marbling is essential for the palatability of beef. In addition, tender beef is demanded by consumers, and connective tissue contributes to the background toughness of beef. Recent studies show that myocytes, adipocytes, and fibroblasts are all derived from a common pool of progenitor cells during embryonic development. It appears that during early embryogenesis, multipotent mesenchymal stem cells first diverge into either myogenic or adipogenic-fibrogenic lineages; myogenic progenitor cells further develop into muscle fibers and satellite cells whereas adipogenic-fibrogenic lineage cells develop into the stromal-vascular fraction of skeletal muscle where reside adipocytes, fibroblasts, and resident fibro-adipogenic progenitor cells (the counterpart of satellite cells). Strengthening myogenesis (i.e., formation of muscle cells) enhances lean growth, promoting intramuscular adipogenesis (i.e., formation of fat cells) increases marbling, and reducing intramuscular fibrogenesis (i.e., formation of fibroblasts and synthesis of connective tissue) improves overall tenderness of beef. Because the abundance of progenitor cells declines as animals age, it is more effective to manipulate progenitor cell differentiation at an early developmental stage. Nutritional, environmental, and genetic factors shape progenitor cell differentiation; however, up to now, our knowledge regarding mechanisms governing progenitor cell differentiation remains rudimentary. In summary, altering mesenchymal progenitor cell differentiation through nutritional management of cows, or fetal programming, is a promising method to improve cattle performance and carcass value.


Asunto(s)
Crianza de Animales Domésticos/métodos , Bovinos/fisiología , Diferenciación Celular , Células Madre Mesenquimatosas/fisiología , Tejido Adiposo/citología , Tejido Adiposo/crecimiento & desarrollo , Animales , Bovinos/crecimiento & desarrollo , Tejido Conectivo/crecimiento & desarrollo , Células del Tejido Conectivo/citología , Femenino , Desarrollo Fetal , Células Madre Mesenquimatosas/citología , Músculo Esquelético/citología , Músculo Esquelético/crecimiento & desarrollo
18.
Int J Obes (Lond) ; 37(4): 568-75, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22614057

RESUMEN

BACKGROUND: Obesity in women of childbearing age is increasing at an alarming rate. Growing evidence shows that maternal obesity induces detrimental effects on offspring health, including pre-disposition to obesity. We have shown that maternal obesity increases fetal intramuscular adipogenesis at mid-gestation. However, the mechanisms are poorly understood. MicroRNAs (miRNAs) regulate mRNA stability. We hypothesized that maternal obesity alters fetal muscle miRNA expression, thereby influencing intramuscular adipogenesis. METHODS: Non-pregnant ewes received a control diet (Con, fed 100% of National Research Council (NRC) recommendations, n=6) or obesogenic diet (OB; 150% NRC recommendations, n=6) from 60 days before to 75 days after conception when the fetal longissimus dorsi (LD) muscle was sampled and miRNA expression analyzed by miRNA microarray. One of miRNAs with differential expression between Con and OB fetal muscle, let-7g, was further tested for its role in adipogenesis and cell proliferation in C3H10T1/2 cells. RESULTS: A total of 155 miRNAs were found with a signal above 500, among which, three miRNAs, hsa-miR-381, hsa-let-7g and bta-miR-376d, were differentially expressed between Con and OB fetuses, and confirmed by quantitative real-time PCR (QRT-PCR) analyses. Reduced expression of miRNA let-7g, an abundantly expressed miRNA, in OB fetal muscle was correlated with higher expression of its target genes. Overexpression of let-7g in C3H10T1/2 cells reduced their proliferation rate. Expression of adipogenic markers decreased in cells overexpressing let-7g, and the formation of adipocytes was also reduced. Overexpression of let-7g decreased expression of inflammatory cytokines. CONCLUSION: Fetal muscle miRNA expression was altered due to maternal obesity, and let-7g downregulation may enhance intramuscular adipogenesis during fetal muscle development in the setting of maternal obesity.


Asunto(s)
Adipogénesis/genética , Desarrollo Fetal/genética , MicroARNs/metabolismo , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Animales , Dieta , Regulación hacia Abajo , Femenino , Regulación del Desarrollo de la Expresión Génica , Fenómenos Fisiologicos Nutricionales Maternos , Músculo Esquelético/embriología , Obesidad/genética , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa , Oveja Doméstica
19.
Phys Rev Lett ; 110(23): 230501, 2013 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-25167475

RESUMEN

Solving linear systems of equations is ubiquitous in all areas of science and engineering. With rapidly growing data sets, such a task can be intractable for classical computers, as the best known classical algorithms require a time proportional to the number of variables N. A recently proposed quantum algorithm shows that quantum computers could solve linear systems in a time scale of order log(N), giving an exponential speedup over classical computers. Here we realize the simplest instance of this algorithm, solving 2×2 linear equations for various input vectors on a quantum computer. We use four quantum bits and four controlled logic gates to implement every subroutine required, demonstrating the working principle of this algorithm.

20.
J Anim Sci ; 90(7): 2201-10, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22266999

RESUMEN

Maternal nutrient restriction leads to alteration in fetal adipose tissue, and offspring from obese mothers have an increased risk of developing obesity. We hypothesized that maternal obesity increases fetal adipogenesis. Multiparous ewes (Columbia/Rambouillet cross 3 to 5 yr of age) carrying twins were assigned to a diet of 100% (Control; CON; n = 4) or 150% (Obese; OB, n = 7) of NRC maintenance requirements from 60 d before conception until necropsy on d 135 of gestation. Maternal and fetal plasma were collected and stored at -80°C for glucose and hormone analyses. Fetal measurements were made at necropsy, and perirenal, pericardial, and subcutaneous adipose tissues were collected from 7 male twin fetuses per group and snap frozen at -80°C. Protein and mRNA expression of fatty acid translocase [cluster of differentiation (CD) 36], fatty acid transport proteins (FATP) 1 and 4, insulin-sensitive glucose transporter (GLUT-4), fatty acid synthase (FASN), and acetyl-coA carboxylase (ACC) was evaluated. Fetal weight was similar, but fetal carcass weight (FCW) was reduced (P < 0.05) in OB versus CON fetuses. Pericardial and perirenal adipose tissue weights were increased (P < 0.05) as a percentage of FCW in OB versus CON fetuses, as was subcutaneous fat thickness (P < 0.001). Average adipocyte diameter was greater (P < 0.01) in the perirenal fat and the pericardial fat (P = 0.06) in OB fetuses compared with CON fetuses. Maternal plasma showed no difference (P > 0.05) in glucose or other hormones, fetal plasma glucose was similar (P = 0.42), and cortisol, IGF-1, and thyroxine were reduced (P ≤ 0.05) in OB fetuses compared with CON fetuses. Protein and mRNA expression of CD 36, FATP 1 and 4, and GLUT-4 were increased (P ≤ 0.05) in all fetal adipose depots in OB versus CON fetuses. The mRNA expression of FASN and ACC was increased (P < 0.05) in OB vs. CON fetuses in all 3 fetal adipose tissue depots. Fatty acid concentrations were increased (P = 0.01) in the perirenal depot of OB versus CON fetuses, and specific fatty acid concentrations were altered (P < 0.05) in subcutaneous and pericardial adipose tissue because of maternal obesity. In conclusion, maternal obesity was associated with increased fetal adiposity, increased fatty acid and glucose transporters, and increased expression of enzymes mediating fatty acid biosynthesis in adipose depots. These alterations, if maintained into the postnatal period, could predispose the offspring to later obesity and metabolic disease.


Asunto(s)
Tejido Adiposo/metabolismo , Proteínas de Transporte de Ácidos Grasos/metabolismo , Feto/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Obesidad/metabolismo , Enfermedades de las Ovejas/metabolismo , Tejido Adiposo/química , Alcaloides , Alimentación Animal , Animales , Dieta , Proteínas de Transporte de Ácidos Grasos/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Femenino , Desarrollo Fetal , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Masculino , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa , Ovinos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...