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981.
Godinho R Llaneza L Blanco JC Lopes S Álvares F García EJ Palacios V Cortés Y Talegón J Ferrand N 《Molecular ecology》2011,20(24):5154-5166
Hybridization between wild species and their domestic counterparts may represent a major threat to natural populations. However, high genetic similarity between the hybridizing taxa makes the detection of hybrids a difficult task and may hinder attempts to assess the impact of hybridization in conservation biology. In this work, we used a combination of 42 autosomal microsatellites together with Y-chromosome microsatellite-defined haplotypes and mtDNA sequences to investigate the occurrence and dynamics of wolf-dog hybridization in the Iberian Peninsula. To do this, we applied a variety of Bayesian analyses and a parallel set of simulation studies to evaluate (i) the differences between Iberian wolves and dogs, (ii) the frequency and geographical distribution of hybridization and (iii) the directionality of hybridization. First, we show that Iberian wolves and dogs form two well-differentiated genetic entities, suggesting that introgressive hybridization is not a widespread phenomenon shaping both gene pools. Second, we found evidence for the existence of hybridization that is apparently restricted to more peripheral and recently expanded wolf populations. Third, we describe compelling evidence suggesting that the dynamics of hybridization in wolf populations is mediated by crosses between male dogs and female wolves. More importantly, the observation of a population showing the occurrence of a continuum of hybrid classes forming mixed packs may indicate that we have underestimated hybridization. If future studies confirm this pattern, then an intriguing avenue of research is to investigate how introgression from free-ranging domestic dogs is enabling wolf populations to adapt to the highly humanized habitats of southern Europe while still maintaining their genetic differentiation. 相似文献
982.
Reina E Puentes C Rojas J García J Ramos FA Castellanos L Aragón M Ospina LF 《Bioorganic & medicinal chemistry letters》2011,21(19):5888-5891
The screen of 10 soft coral extracts collected from the Colombian Caribbean Sea in the TPA-induced ear edema model allowed us to identify Eunicea fusca extract among others as an interesting source of active compounds. The new diterpene, fuscoside E (1), along with the known fuscoside B (2), fuscol (3), (+)-germacrene D (4) and a mixture of six sterols (5-10), were isolated from this soft coral. Their structures were elucidated by 1D and 2D NMR spectroscopy techniques. Fuscoside E (1) absolute stereochemistry was determined by chiroptical methods. Fuscoside E (1) and B (2) showed strong anti-inflammatory in the above mentioned bioassay. Additionally, fuscoside E (1) and the sterol mixture (5-10) presented antifouling activity against bacterial strains involved in surface colonization. 相似文献
983.
Rafael Y. Kuradomi Márcio A. Figueiredo Carlos F. C. Lanes Carlos E. da Rosa Daniela V. Almeida Rodrigo Maggioni Maeli D. P. Silva Luis F. Marins 《Transgenic research》2011,20(3):513-521
The aim of the present study was to analyse the morphology of white skeletal muscle in males and females from the GH-transgenic
zebrafish (Danio rerio) lineage F0104, comparing the expression of genes related to the somatotrophic axis and myogenesis. Histological analysis
demonstrated that transgenic fish presented enhanced muscle hypertrophy when compared to non-transgenic fish, with transgenic
females being more hypertrophic than transgenic males. The expression of genes related to muscle growth revealed that transgenic
hypertrophy is independent from local induction of insulin-like growth factor 1 gene (igf1). In addition, transgenic males exhibited significant induction of myogenin gene (myog) expression, indicating that myog may mediate hypertrophic growth in zebrafish males overexpressing GH. Induction of the
α-actin gene (acta1) in males, independently from transgenesis, also was observed. There were no significant differences in total protein content
from the muscle. Our results show that muscle hypertrophy is independent from muscle igf1, and is likely to be a direct effect of excess circulating GH and/or IGF1 in this transgenic zebrafish lineage. 相似文献
984.
Background
Genetic relatedness or similarity between individuals is a key concept in population, quantitative and conservation genetics. When the pedigree of a population is available and assuming a founder population from which the genealogical records start, genetic relatedness between individuals can be estimated by the coancestry coefficient. If pedigree data is lacking or incomplete, estimation of the genetic similarity between individuals relies on molecular markers, using either molecular coancestry or molecular covariance. Some relationships between genealogical and molecular coancestries and covariances have already been described in the literature.Methods
We show how the expected values of the empirical measures of similarity based on molecular marker data are functions of the genealogical coancestry. From these formulas, it is easy to derive estimators of genealogical coancestry from molecular data. We include variation of allelic frequencies in the estimators.Results
The estimators are illustrated with simulated examples and with a real dataset from dairy cattle. In general, estimators are accurate and only slightly biased. From the real data set, estimators based on covariances are more compatible with genealogical coancestries than those based on molecular coancestries. A frequently used estimator based on the average of estimated coancestries produced inflated coancestries and numerical instability. The consequences of unknown gene frequencies in the founder population are briefly discussed, along with alternatives to overcome this limitation.Conclusions
Estimators of genealogical coancestry based on molecular data are easy to derive. Estimators based on molecular covariance are more accurate than those based on identity by state. A correction considering the random distribution of allelic frequencies improves accuracy of these estimators, especially for populations with very strong drift. 相似文献985.
Zhou Q Stefano JE Harrahy J Finn P Avila L Kyazike J Wei R Van Patten SM Gotschall R Zheng X Zhu Y Edmunds T Pan CQ 《Bioconjugate chemistry》2011,22(4):741-751
Engineering proteins for selective tissue targeting can improve therapeutic efficacy and reduce undesired side effects. The relatively high dose of recombinant human acid α-glucosidase (rhGAA) required for enzyme replacement therapy of Pompe disease may be attributed to less than optimal muscle uptake via the cation-independent mannose 6-phosphate receptor (CI-MPR). To improve muscle targeting, Zhu et al. (1) conjugated periodate oxidized rhGAA with bis mannose 6-phosphate bearing synthetic glycans and achieved 5-fold greater potency in a murine Pompe efficacy model. In the current study, we systematically evaluated multiple strategies for conjugation based on a structural homology model of GAA. Glycan derivatives containing succinimide, hydrazide, and aminooxy linkers targeting free cysteine, lysines, and N-linked glycosylation sites on rhGAA were prepared and evaluated in vitro and in vivo. A novel conjugation method using enzymatic oxidation was developed to eliminate side oxidation of methionine. Conjugates derived from periodate oxidized rhGAA still displayed the greatest potency in the murine Pompe model. The efficiency of conjugation and its effect on catalytic activity were consistent with predictions based on the structural model and supported its use in guiding selection of appropriate chemistries. 相似文献
986.
Morales-Avila E Ferro-Flores G Ocampo-García BE De León-Rodríguez LM Santos-Cuevas CL García-Becerra R Medina LA Gómez-Oliván L 《Bioconjugate chemistry》2011,22(5):913-922
Integrin α(V)β(3) plays a critical role in tumor angiogenesis and metastasis. Suitably radiolabeled cyclic RGD peptides can be used for noninvasive imaging of α(V)β(3) expression. The aim of this research was to prepare a multimeric system of technetium-99m-labeled gold nanoparticles conjugated to c[RGDfK(C)] and to evaluate its biological behavior as a potential radiopharmaceutical for molecular imaging of tumor angiogenesis. Hydrazinonicotinamide-GGC (HYNIC-GGC) and c[RGDfK(C)] peptides were synthesized and conjugated to gold nanoparticles (AuNP, 20 nm) by means of spontaneous reaction of the thiol groups of cysteine. The nanoconjugate was characterized by TEM, FT-IR, UV-vis, XPS, and Raman spectroscopy. To obtain (99m)Tc-HYNIC-GGC-AuNP-c[RGDfK(C)] ((99m)Tc-AuNP-RGD), the (99m)Tc-HYNIC-GGC radiopeptide was first prepared and added to 1.5 mL of AuNP solution (1 nM) followed by c[RGDfK(C)] (10 μL, 50 μM) at 18 °C with stirring for 15 min. Radiochemical purity (RP) was determined by size-exclusion HPLC and ITLC-SG analyses. In vitro binding studies were carried out in α(V)β(3) receptor-positive C6 glioma cancer cells. Biodistribution studies were accomplished in athymic mice with C6-induced tumors with blocked and nonblocked receptors, and images were obtained using a micro-SPECT/CT. TEM and spectroscopy techniques demonstrated that AuNPs were functionalized with peptides. RP was 96 ± 2% without postlabeling purification. (99m)Tc-AuNP-RGD showed specific recognition for α(V)β(3) integrins expressed in C6 cells, and 3 h after i.p. administration in mice, the tumor uptake was 8.18 ± 0.57% ID/g. Micro-SPECT/CT images showed evident tumor uptake. (99m)Tc-AuNP-RGD demonstrates properties suitable for use as a target-specific agent for molecular imaging of tumor α(V)β(3) expression. 相似文献
987.
988.
Ana E Bergues Pupo Juan Bory Reyes Luis E Bergues Cabrales Jesús M Bergues Cabrales 《Biomedical engineering online》2011,10(1):1-14
Background
During the cardiac cycle, the heart normally produces repeatable physiological sounds. However, under pathologic conditions, such as with heart valve stenosis or a ventricular septal defect, blood flow turbulence leads to the production of additional sounds, called murmurs. Murmurs are random in nature, while the underlying heart sounds are not (being deterministic).Innovation
We show that a new analytical technique, which we call Digital Subtraction Phonocardiography (DSP), can be used to separate the random murmur component of the phonocardiogram from the underlying deterministic heart sounds.Methods
We digitally recorded the phonocardiogram from the anterior chest wall in 60 infants and adults using a high-speed USB interface and the program Gold Wave http://www.goldwave.com. The recordings included individuals with cardiac structural disease as well as recordings from normal individuals and from individuals with innocent heart murmurs. Digital Subtraction Analysis of the signal was performed using a custom computer program called Murmurgram. In essence, this program subtracts the recorded sound from two adjacent cardiac cycles to produce a difference signal, herein called a "murmurgram". Other software used included Spectrogram (Version 16), GoldWave (Version 5.55) as well as custom MATLAB code.Results
Our preliminary data is presented as a series of eight cases. These cases show how advanced signal processing techniques can be used to separate heart sounds from murmurs. Note that these results are preliminary in that normal ranges for obtained test results have not yet been established.Conclusions
Cardiac murmurs can be separated from underlying deterministic heart sounds using DSP. DSP has the potential to become a reliable and economical new diagnostic approach to screening for structural heart disease. However, DSP must be further evaluated in a large series of patients with well-characterized pathology to determine its clinical potential. 相似文献989.
Pineda C Amezcua-Guerra LM Solano C Rodriguez-Henríquez P Hernández-Díaz C Vargas A Hofmann F Gutiérrez M 《Arthritis research & therapy》2011,13(1):R4
Introduction
In this study, we aimed to investigate ultrasonographic (US) changes suggestive of gouty arthritis in the hyaline cartilage, joints and tendons from asymptomatic individuals with hyperuricemia. 相似文献990.
Cea Soriano L Rothenbacher D Choi HK García Rodríguez LA 《Arthritis research & therapy》2011,13(2):R39