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101.
AINTEGUMENTA (ANT) promotes initiation and growth of ovule integuments which cell fate is specified by ovule identity factors, such as SEEDSTICK (STK), SHATTERPROOF1 (SHP1) and SHATTERPROOF2 (SHP2). To study the genetic interaction between ANT and the ovule identity genes, we have obtained a stk shp1 shp2 ant quadruple mutant. The molecular and morphological characterization of the quadruple mutant and its comparison with the stk shp1 shp2 triple mutant, the shp1 shp2 ant triple mutant and the stk ant double mutant are here presented.  相似文献   
102.

Background

To assess the reliability of fetal heart volume measurement by three-dimensional sonography (3DUS) using the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) method.

Methods

This reliability study enrolled 30 pregnant women with singleton healthy pregnancies between 19 and 34 weeks of gestation. All volume acquirements were performed with a convex volumetric transducer (C3-7ED) coupled to an Accuvix XQ sonography device (Medison, Korea). The XI VOCAL 10 planes was the method of choice for volumetric measurement. 3D datasets were analyzed by two observers (EQSB and HJFM); fetal heart volume was measured twice by the first and once by the second observer to calculate intra and interobserver reproducibility. Statistical analysis used pareated Student's t test (p) and calculated Intraclass correlation coefficients (ICC). Bland-Altman plots were also constructed.

Results

We observed an excellent intra- and interobserver reliability for fetal cardiac volume assessed by XI VOCAL. For the intraobserver the ICC was 0.998 (95% CI: 0.997; 0.999), with mean of differences of 0.12 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.130). For interobserver the ICC was 0.899 (95%CI: 0.996; 0.998), mean of differences 0.05 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.175).

Conclusion

Fetal cardiac volume assessed by 3DUS using XI VOCAL method is highly reproducible between 19 to 34 gestational weeks.  相似文献   
103.

Introduction

The purpose of this study was to evaluate the effects of L-4F, an apolipoprotein A-1 mimetic peptide, alone or with pravastatin, in apoE-/-Fas-/-C57BL/6 mice that spontaneously develop immunoglobulin G (IgG) autoantibodies, glomerulonephritis, osteopenia, and atherosclerotic lesions on a normal chow diet.

Methods

Female mice, starting at eight to nine weeks of age, were treated for 27 weeks with 1) pravastatin, 2) L-4F, 3) L-4F plus pravastatin, or 4) vehicle control, followed by disease phenotype assessment.

Results

In preliminary studies, dysfunctional, proinflammatory high-density lipoproteins (piHDL) were decreased six hours after a single L-4F, but not scrambled L-4F, injection in eight- to nine-week old mice. After 35 weeks, L-4F-treated mice, in the absence/presence of pravastatin, had significantly smaller lymph nodes and glomerular tufts (PL, LP < 0.05), lower serum levels of IgG antibodies to double stranded DNA (dsDNA) (PL < 0.05) and oxidized phospholipids (oxPLs) (PL, LP < 0.005), and elevated total and vertebral bone mineral density (PL, LP < 0.01) compared to vehicle controls. Although all treatment groups presented larger aortic root lesions compared to vehicle controls, enlarged atheromas in combination treatment mice had significantly less infiltrated CD68+ macrophages (PLP < 0.01), significantly increased mean α-actin stained area (PLP < 0.05), and significantly lower levels of circulating markers for atherosclerosis progression, CCL19 (PL, LP < 0.0005) and VCAM-1 (PL < 0.0002).

Conclusions

L-4F treatment, alone or with pravastatin, significantly reduced IgG anti-dsDNA and IgG anti-oxPLs, proteinuria, glomerulonephritis, and osteopenia in a murine lupus model of accelerated atherosclerosis. Despite enlarged aortic lesions, increased smooth muscle content, decreased macrophage infiltration, and decreased pro-atherogenic chemokines in L-4F plus pravastatin treated mice suggest protective mechanisms not only on lupus-like disease, but also on potential plaque remodeling in a murine model of systemic lupus erythematosus (SLE) and accelerated atherosclerosis.  相似文献   
104.
We report 24 records of giant armadillo roadkill on Brazilian highways in the Cerrado, Pantanal and Amazon biomes illustrating that highways are a threat to this species. However, we also documented the species using underpasses, demonstrating that these structures could help to reduce the risk of roadkill for giant armadillos.  相似文献   
105.
106.
The role of NKT cells on antitumor activity of CpG oligodeoxynucleotides (ODNs) was evaluated by peritumoral injections of CpG-ODNs in s.c. melanoma-bearing mice of strains differing in the number of NKT cells (athymic nude mice, recombination-activating gene(-/-)/transgenic V(alpha)14/Vbeta8.2 mice that generate NKT cells; J(alpha)281(-/-) mice and CD1(-/-) mice, which both have a strongly reduced number of NKT cells; and C57BL/6 wild-type mice). Tumor growth was significantly inhibited in strains enriched or depleted of NKT cells. The two murine strains having a reduced number of NKT cells differed significantly in the CpG-dependent tumor growth inhibition: in J(alpha)281(-/-) mice this inhibition was superimposable to that observed in C57BL/6 mice, while in CD1(-/-) mice the inhibition was dramatic. The increased tumor inhibition in CD1(-/-) correlated with a significantly higher ratio of IFN-gamma-IL-4 production in response to CpG as compared with C57BL/6 and J(alpha)281(-/-) mice. Experiments in which preparations of APCs and lymphocytes of the three strains were mixed showed that in the presence of APCs not expressing CD1, the production of CpG-ODN-induced type 1 cytokines was higher. Phenotype analysis of IFN-gamma- and IL-4-producing cells revealed that the differences between CD1(-/-) and C57BL/6 in the production of these two cytokines were mainly due to CD3(+) T lymphocytes. These data point to a regulatory role for the CD1 molecule in antitumor activity induced by danger signals, independently of V(alpha)14 NKT cells. The identification of a CD1-dependent suppressive subpopulation(s) might have important implications for the study of tolerance in the context of cancer, autoimmunity, and transplantation.  相似文献   
107.

Background  

More optimistic perceptions of cardiovascular disease risk are associated with substantively lower rates of cardiovascular death among men. It remains unknown whether this association represents causality (i.e. perception leads to actions/conditions that influence cardiovascular disease occurrence) or residual confounding by unmeasured factors that associate with risk perceptions and with physiological processes that promote cardiovascular disease (i.e. inflammation or endothelial dysfunction).  相似文献   
108.
109.
Elevated levels of plasma homocysteine (Hcy), a risk factor for coronary artery disease (CAD), can result from genetic errors, e.g., the methylenetetrahydrofolate reductase (MTHFR) polymorphism, or nutritional deficiencies, e.g., in vitamin B12 and folate. The mechanism by which Hcy induces atherosclerosis is not fully understood. Recently, Hcy has also been observed to induce DNA damage. In this study, we have investigated whether DNA damage is related to the C677T variant in the MTHFR gene and to plasma levels of Hcy, B12, and folate in patients with CAD. Patients ( n=46) with angiographically proven CAD were studied by using the micronucleus (MN) test, an accepted method for evaluating genetic instability. TT patients had plasma Hcy levels higher than those with the CT or CC genotypes (27.8+/-5.2 vs 13.7+/-2.2 and 12.9+/-1.9 micro mol/l, respectively; P=0.02). Patients with multi-vessel disease had higher plasma Hcy levels (11.6+/-1.2, 22.0+/-4.7, 19.3+/-3.9 micromol/l for one-, two- and three-vessel disease, respectively; P=0.05). The MN index increased with the number of affected vessels (8.4+/-0.7, 11.1+/-2.0, 14.2+/-1.7 for one-, two-, and three-vessels disease, respectively; P=0.02) and was significantly higher in subjects with the TT genotype compared with the CC or CT genotypes (15.7+/-2.4 vs 8.9+/-1.7 and 9.9+/-0.8; P=0.02). The MN index was also correlated negatively with plasma B12 concentration ( r=-0.343; P=0.019) and positively with plasma Hcy ( r=0.429, P=0.005). These data indicate that the MN index is associated with the severity of CAD and is related to the MTHFR polymorphism, suggesting an interesting link between coronary atherosclerosis and genetic instability in humans.  相似文献   
110.
Addition of 200 mm of a polyol to anthocyanin containing carrot (Daucus carota L.) cells in suspension culture decreased turgor pressure to zero and induced hyperpolarization of the membrane potential and acidification of the medium due to H+ extrusion. These changes were shown to be slightly affected by vanadate. In parallel, a decrease in intracellular ATP and total adenylate concentrations were observed. However, when the osmoticum was NaCl acidification of the medium occurred in the absence of considerable changes in intracellular ATP concentration. These results are interpreted as indicating that a drop of turgor, by addition of a polyol, triggers a proton extrusion activity which is only slightly inhibited by vanadate but apparently ATP utilizing. The observed decrease in ATP level occurs without a change in respiration rate and is accompanied by a drop in total adenylate pool. However when NaCl is the osmoticum it is assumed that ΔμH+ is enhanced through a Na+/H+ antiporter. The difference between the two types of osmotica as related to their ability to penetrate through the cellular membrane is discussed.  相似文献   
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