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81.
82.

Background

Calreticulin, a Ca2+-buffering chaperone of the endoplasmic reticulum, is highly expressed in the embryonic heart and is essential for cardiac development. After birth, the calreticulin gene is sharply down regulated in the heart, and thus, adult hearts have negligible levels of calreticulin. In this study we tested the role of calreticulin in the adult heart.

Methodology/Principal Findings

We generated an inducible transgenic mouse in which calreticulin is targeted to the cardiac tissue using a Cre/loxP system and can be up-regulated in adult hearts. Echocardiography analysis of hearts from transgenic mice expressing calreticulin revealed impaired left ventricular systolic and diastolic function and impaired mitral valve function. There was altered expression of Ca2+ signaling molecules and the gap junction proteins, Connexin 43 and 45. Sarcoplasmic reticulum associated Ca2+-handling proteins (including the cardiac ryanodine receptor, sarco/endoplasmic reticulum Ca2+-ATPase, and cardiac calsequestrin) were down-regulated in the transgenic hearts with increased expression of calreticulin.

Conclusions/Significance

We show that in adult heart, up-regulated expression of calreticulin induces cardiomyopathy in vivo leading to heart failure. This is due to an alternation in changes in a subset of Ca2+ handling genes, gap junction components and left ventricle remodeling.  相似文献   
83.
Truffles are prized and nutrition‐rich edible hypogeous fungi. The aim of this study was a comprehensive investigation of chemical composition of Burgundy truffle (Tuber aestivum Vittad .). We tried to answer the question: what is the impact of the environment on the truffle quality. To know the nutritional value of Burgundy truffle we compared lipids, proteins, saccharides, polyphenolics, flavonoids, total sterols, ergosterol, volatile flavour and aroma compounds content in fruit bodies of the fungus collected in three different geographical regions, i.e., Poland, Slovakia, and Italy. A comparison of the above mentioned compounds is especially interesting due to environmental and climatic differences among the studied geographical regions. Results revealed that fruit bodies of Taestivum from Poland and Slovakia possessed nearly similar content of proteins, total sterols, and saccharides. The fruiting bodies from Italy contained significantly larger amounts of most of the investigated compounds. In turn, Polish specimens had higher content of lipids and polyphenolics than Slovak and Italian ones. We have found higher similarity of volatile compounds composition between Polish and Italian specimens than those of Polish and Slovak origin.  相似文献   
84.
Conidiobolus coronatus is an entomopathogenic fungus which has a potential as a biological control agent of insects. The cuticular and internal lipid composition of infected and noninfected Tettigonia viridissima males were analyzed by GC/MS. A total of 49 compounds were identified in the infected and noninfected males, including fatty acids, fatty acid methyl esters (FAMEs), n‐alkanes, alcohols, sterols, and other organic compounds. The most abundant components of the cuticular and internal lipids of the insects were fatty acids. After exposure to C. coronatus, the cuticular lipids of the T. viridissima males contained 17 free fatty acids from C(8) to C(22), while the cuticular lipids of the noninfected insects contained only 15 fatty acids from C(12) to C(24). The cuticular and internal lipids of both the infected and the noninfected males also contained five FAMEs from C(15) to C(19), seven n‐alkanes from C(25) to C(34), five alcohols from C(16) to C(25), five sterols, and the following six other organic compounds: azelaic acid, phenylacetic acid, glutaric acid, benzoic acid, sebacic acid, and glycerol. The compounds which were present only in the cuticular lipids of the infected males could be due to fungal infection.  相似文献   
85.

Objective

To present current guidelines regarding treatment of mastocytosis in pregnancy on the example of observed patients.

Design

Case control national study.

Setting

Polish Center of the European Competence Network on Mastocytosis (ECNM).

Population or Sample

23 singleton spontaneous pregnancies in 17 women diagnosed with mastocytosis in years 1999–2014, before becoming pregnant.

Methods

Prospective analysis outcomes of pregnancies and deliveries.

Main Outcome Measures

Survey developed in cooperation with the Spanish Instituto de Estudios de Mastocitosis de Castilla-La Mancha (CLMast), Hospital Virgen del Valle, Toledo, Red Espańola de Mastocitosis (REMA), Spain.

Results

All 23 pregnancies resulted from natural conception. Obstetrical complications recorded in the first trimester included spontaneous miscarriage (5 pregnancies). Four patients delivered preterm, including one delivery due to preeclampsia at 26 weeks which resulted with neonate death due to extreme prematurity. Five women delivered via cesarean: four due to obstetrical indications and one due to mastocytosis, during which no anesthesia related complications were recorded. Of patients delivering vaginally, two received extradural anesthesia, three required oxytocin infusion due to uterine hypotonia. No labor complications were recorded. In one woman with pregnancy-induced hypertension, early puerperium was complicated by the presence of persistent arterial hypertension. One neonate was born with the signs of cutaneous mastocytosis. Another neonate was diagnosed with Patau syndrome. Four women were treated for mastocytosis prior to conception and continued therapy after becoming pregnant. One patient was put on medications in the first trimester due to worsening of her symptoms. Pregnancy exerted only a slight effect on the intensity and frequency of mastocytosis-related symptoms observed. Worsening of the disease-related symptoms was documented in only four patients (23%). None of the patients showed the signs of anaphylaxis, either before becoming pregnant, or during pregnancy and puerperium.

Conclusions

There is no contraindication to pregnancy when mastocystosis-related pathologies are under appropriate medical control.  相似文献   
86.
Currently, studies connected with Computational Fluid Dynamic (CFD) techniques focus on assessing hemodynamic of blood flow in vessels in different conditions e.g. after stent-graft’s placement. The paper propose a novel method of standardization of results obtained from calculations of stent-grafts'' “pushing forces” (cumulative WSS—Wall Shear Stress), and describes its usefulness in diagnostic process. AngioCT data from 27 patients were used to reconstruct 3D geometries of stent-grafts which next were used to create respective reference cylinders. We made an assumption that both the side surface and the height of a stent-graft and a reference cylinder were equal. The proposed algorithm in conjunction with a stent-graft “pushing forces” on an implant wall, allowed us to determine which spatial configuration of a stent-graft predispose to the higher risk of its migration. For stent-grafts close to cylindrical shape (shape factor φ close to 1) WSS value was about 267Pa, while for stent-grafts different from cylindrical shape (φ close to 2) WSS value was about 635Pa. It was also noticed that deformation in the stent-graft’s bifurcation part impaired blood flow hemodynamic. Concluding the proposed algorithm of standardization proved its usefulness in estimating the WSS values that may be useful in diagnostic process. Angular bends or tortuosity in bifurcations of an aortic implant should be considered in further studies of estimation of the risk of implantation failure.  相似文献   
87.
88.

Background

Neointima forming after stent implantation consists of vascular smooth muscle cells (VSMCs) in 90%. Growth factors TGF-β1, PDGFB, EGF, bFGF and VEGF-A play an important role in VSMC proliferation and migration to the tunica intima after arterial wall injury. The aim of this paper was an analysis of functional polymorphisms in genes encoding TGF-β1, PDGFB, EGF, bFGF and VEGF-A in relation to in-stent restenosis (ISR).

Materials and Methods

265 patients with a stable coronary artery disease (SCAD) hospitalized in our center in the years 2007–2011 were included in the study. All patients underwent stent implantation at admission to the hospital and had another coronary angiography performed due to recurrence of the ailments or a positive result of the test assessing the coronary flow reserve. Angiographically significant ISR was defined as stenosis >50% in the stented coronary artery segment. The patients were divided into two groups–with angiographically significant ISR (n = 53) and without significant ISR (n = 212). Additionally, the assessment of late lumen loss (LLL) in vessel was performed. EGF rs4444903 polymorphism was genotyped using the PCR-RFLP method whilst rs1800470 (TGFB1), rs2285094 (PDGFB) rs308395 (bFGF) and rs699947 (VEGF-A) were determined using the TaqMan method.

Results

Angiographically significant ISR was significantly less frequently observed in the group of patients with the A/A genotype of rs1800470 polymorphism (TGFB1) versus patients with A/G and G/G genotypes. In the multivariable analysis, LLL was significantly lower in patients with the A/A genotype of rs1800470 (TGFB1) versus those with the A/G and G/G genotypes and higher in patients with the A/A genotype of the VEGF-A polymorphism versus the A/C and C/C genotypes. The C/C genotype of rs2285094 (PDGFB) was associated with greater LLL compared to C/T heterozygotes and T/T homozygotes.

Conclusions

The polymorphisms rs1800470, rs2285094 and rs6999447 of the TGFB1, PDGFB and VEGF-A genes, respectively, are associated with LLL in patients with SCAD treated by PCI with a metal stent implantation.  相似文献   
89.
90.
Previous studies with diploid yeast have shown that the deletion of one allele at a single locus typically has little impact on fitness under conditions promoting fast growth. Here, we confirm and quantify this finding. The strong dominance of functional over nonfunctional alleles is predicted by the metabolic control theory which assumes that the cell is a system of metabolic fluxes and that the total metabolic rate is equivalent to fitness. To test whether these requirements are critical, we tested dominance under conditions of long‐term starvation when metabolism is low and thus the metabolic activities of proteins are likely inadequate or imbalanced. More fundamentally, the central assumption of the model, that high metabolic rate translates into high fitness, appears implausible. Contrary to these conjectures, we found that the mean rate of survival of starving heterozygotes was affected only slightly more than was the mean rate of growth under good conditions. Under none of the two treatments the central prediction of the model, that fitness of heterozygous strains is higher for the enzymatic proteins than for nonenzymatic ones, was confirmed. Our data add to growing uncertainty whether the metabolic control theory is sufficient to explain the remarkable ubiquity of strong genetic dominance.  相似文献   
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