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141.
142.
BACKGROUND: To determine if the fetus was affected by maternal antibodies to BMP‐2, the antibody response and developmental effects in fetuses from does immunized against recombinant human BMP‐2 were evaluated. METHODS: Female New Zealand White rabbits received four intramuscular injections (on premating days 1, 8, 22, and 43 [3 days before mating]) of saline and adjuvant (TiterMax® Gold [control]) or recombinant human BMP‐2 (2 mg/dose) and adjuvant (treated). On GD 29, fetuses were examined, and maternal and fetal anti‐BMP‐2 titer levels and neutralizing activity were assessed. RESULTS: Anti‐BMP‐2 antibodies were detected in 17 of 18 treated does (127 of 151 fetuses), and low levels were detected in 2 of 16 control does (no fetal exposure observed). In general, levels of fetal anti‐BMP‐2 antibodies were similar to those in the does, and pregnancy did not boost the immune response to BMP‐2. There were no effects of immunization or anti‐BMP‐2 antibody titer levels on embryo–fetal viability, fetal weight, or fetal external, visceral, or skeletal development. Only a small number of fetuses (n = 4) displayed detectable neutralizing anti‐BMP‐2 antibodies, but there were no treatment‐related effects in those fetuses. CONCLUSIONS: The lack of embryo–fetal effects may be due to dosage effects of neutralizing anti‐BMP‐2 antibodies, timing of exposure (stage and duration) to neutralizing anti‐BMP‐2 antibodies, and/or redundancy of effects of the various BMPs. Birth Defects Res (Part B) 92:543–552, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
143.
The small annual grass Brachypodium distachyon (Brachypodium) is rapidly emerging as a powerful model system to study questions unique to the grasses. Many Brachypodium resources have been developed including a whole genome sequence, highly efficient transformation and a large germplasm collection. We developed a genetic linkage map of Brachypodium using single nucleotide polymorphism (SNP) markers and an F2 mapping population of 476 individuals. SNPs were identified by targeted resequencing of single copy genomic sequences. Using the Illumina GoldenGate Genotyping platform we placed 558 markers into five linkage groups corresponding to the five chromosomes of Brachypodium. The unusually long total genetic map length, 1,598 centiMorgans (cM), indicates that the Brachypodium mapping population has a high recombination rate. By comparing the genetic map to genome features we found that the recombination rate was positively correlated with gene density and negatively correlated with repetitive regions and sites of ancestral chromosome fusions that retained centromeric repeat sequences. A comparison of adjacent genome regions with high versus low recombination rates revealed a positive correlation between interspecific synteny and recombination rate.  相似文献   
144.
The purpose of this study was to assess the inflammatory nature of obesity and its effect on blood and bone marrow endothelial cell populations. Obese patients (BMI ≥30) had significantly higher concentrations of the inflammatory marker C-reactive protein (CRP) (P = 0.03) and lower concentrations of the anti-inflammatory cytokine interleukin-10 (IL-10) (P = 0.05). This cytokine profile is consistent with obesity being an inflammatory condition and is further supported by the significant correlation between total white blood cell count and BMI (r = 0.15; P = 0.035). High BMI was associated with significantly lower numbers of early endothelial cells (CD45(-)/CD34(+)) in the bone marrow (r = -0.20; P = 0.0068). There was also a significant inverse correlation between BMI and a more mature endothelial cell phenotype (CD45(-)/31(+)) in the blood (r = -0.17; P = 0.02). In addition, there was a significant correlation between BMI- and endothelial-related cells of hematopoietic origin (CD133(+)/VEGFR-2(+)) in the bone marrow (r = -0.26; P = 0.0007). Patients with higher plasma IL-10 and insulin-like growth factor (IGF) concentrations had higher numbers of endothelial phenotypes in the bone marrow suggesting a protective effect of these anti-inflammatory cytokines. In conclusion, this work confirms the inflammatory nature of obesity and is the first to report that obesity is associated with reduced endothelial cell numbers in the bone marrow of humans. These effects of obesity may be a potential mechanism for impaired tissue repair in obese patients.  相似文献   
145.
Increasing Na delivery to the connecting tubule (CNT) causes afferent arteriole (Af-Art) dilation, a process we call CNT glomerular feedback (CTGF). Angiotensin II (ANG II) in the CNT lumen enhances CTGF via PKC. We hypothesized that luminal ANG II stimulates CTGF via activation of protein kinase C (PKC), NADPH oxidase 2 (NOX2), and enhanced production of superoxide (O(2)(-)). Rabbit Af-Arts and adherent CNTs were microdissected and microperfused in vitro. Dilation of the Af-Art was induced by increasing luminal CNT NaCl from 0 to 5, 10, 30, 45, and 80 mM, and the concentration of NaCl that elicited a half-maximal response (EC(50)) was calculated. Compared with vehicle, adding ANG II (10(-9) M) to the CNT lumen reduced EC(50) from 37 ± 3 to 14 ± 1 mM (P < 0.001), indicating ANG II potentiates CTGF. In the presence of ANG II, the O(2)(-) scavenger tempol (10(-4) M) increased EC(50) from 20 ± 4 to 41 ± 3 mM (P < 0.01), the NOX inhibitor apocynin (10(-5) M) increased EC(50) from 17 ± 2 to 39 ± 4 mM (P < 0.01), and the specific NOX2 inhibitor gp91ds-tat (10(-5) M) increased EC(50) from 19 ± 2 to 34 ± 2 mM (P < 0.01). However, tempol, apocynin, and gp91ds-tat had no effect on CTGF in the absence of ANG II. Compared with vehicle, the PKC activator PMA (2 × 10(-7) M) decreased EC(50) from 35 ± 2 to 14 ± 1 (P < 0.001). In the presence of PMA, tempol increased EC(50) from 14 ± 2 to 35 ± 2 mM (P < 0.01). We conclude the PKC/NOX2/O(2)(-) pathway mediates the enhancement of CTGF by luminal ANG II but it does not participate in CTGF in the absence of ANG II.  相似文献   
146.
147.
Oribatid mites are diverse and abundant terrestrial soil arthropods that are involved in decomposition of organic matter and nutrient cycling. As indicated by fossils starting from the Devonian, they evolved varied mechanisms and structures for defense from predators. We investigated four of these defensive structures (ptychoid body, hologastry, mineralization and opisthonotal glands) and used ancestral character state reconstruction to determine whether they evolved convergently and how many times this may have happened. Phylogenetic trees based on 18S rDNA were constructed for 42 oribatid mite species and two outgroup taxa using likelihood and Bayesian algorithms. The results suggest that at least three of the four defensive structures evolved convergently several times; for opisthonotal glands convergent evolution remains equivocal. This high level of convergence indicates that predation has been an important factor throughout the evolution of oribatid mites, contributing to morphological diversity and potentially also to species richness, as there are indications that some taxa radiated after the evolution of defense structures. Despite the ancientness of oribatid mites, defense structures seems to have been rarely lost, suggesting that they still are functional and necessary to reduce predation, rather than being 'ghosts of predation past'.  相似文献   
148.
Techniques that are currently available for estimating stature and body mass from European skeletal remains are all subject to various limitations. Here, we develop new prediction equations based on large skeletal samples representing much of the continent and temporal periods ranging from the Mesolithic to the 20th century. Anatomical reconstruction of stature is carried out for 501 individuals, and body mass is calculated from estimated stature and biiliac breadth in 1,145 individuals. These data are used to derive stature estimation formulae based on long bone lengths and body mass estimation formulae based on femoral head breadth. Prediction accuracy is superior to that of previously available methods. No systematic geographic or temporal variation in prediction errors is apparent, except in tibial estimation of stature, where northern and southern European formulae are necessary because of the presence of relatively longer tibiae in southern samples. Thus, these equations should bebroadly applicable to European Holocene skeletal samples.  相似文献   
149.
Our understanding of the human and biophysical dimensions of tropical dry forest change and its cumulative effects is still in the early stages of academic discovery. The papers in this special section on Neotropical dry forests cover a wide range of sites and problems ranging from the use of multispectral and hyperspectral remote sensing platforms to the impact of hurricanes on tropical dry forest regeneration. Here, we present to the scientific community the results of a workshop on which research priorities for tropical dry forests were discussed. This discussion focuses on the need to develop linkages between remote sensing, ecological, and social science research. The incorporation of social sciences into ecological research could contribute dramatically to our understandings of tropical dry forests by providing important contextual information to ecologists, and by helping to develop an important science–policy–public nexus on which environmental management can succeed.  相似文献   
150.
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