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An accurate capillary gas chromatographic method using different internal standards for determining free fatty acids, cholesterol, cholesteryl esters, and triacylglycerols in plasma and other biological sources is described. It is designed to give information about species composition and, consequently, more detailed information about changes in lipid metabolism of patients suffering from metabolic disorders. After plasma extraction the lipids, except phospholipids, are directly examined without any further derivatization. For free fatty acid determination the programmed temperature vaporizer (PTV) injector was heated from 40 degrees C (sample introduction) to 190 degrees C. In a second gas chromatographic run the PTV-injector system was heated from 60 degrees C (sample introduction) to 400 degrees C, enabling the determination of free cholesterol, cholesteryl esters, and triacylglycerol species, differing in the number of carbon atoms. Evaluation of the values obtained resulted in coefficients of variation (%) of 1.0-2.8, 2.0, 1.29-2.24, and 2.8, for free fatty acid standards, plasma free fatty acids, cholesterol and cholesteryl ester standards, and plasma total cholesterol, respectively. Free fatty acids, cholesterol, and cholesteryl esters were not influenced by storage of plasma at -24 degrees C up to 4 days prior to extraction. The results of the gas chromatographic method and the enzymatic methods correlated well. Determination by gas chromatography yielded higher total cholesterol and lower triacylglycerol values than those values obtained by enzymatic methods.  相似文献   
3.

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   
4.
Here we report a transgenic mouse line that exhibits significant deviations from a classic pattern of parental imprinting. When the transgene is passed through the female germline, it is completely silenced in some offspring while in others expression is reduced. This variable expressivity does not appear to be the result of differences in the presence of unlinked modifiers. Female transmission of the transgene is associated with hypermethylation. The transgene is generally reactivated on passage through the male germline. Extended pedigrees reveal complex patterns of inheritance of the phenotype. The most likely explanation for this result is that the imprint is not completely erased and reset when passed through the germline of either sex. FISH analysis reveals that the transgene has integrated into chromosome 3 band E3, a region not known to carry imprinted genes, and the integration site shows no sign of allele-specific differential methylation. These findings, in conjunction with other recent work, raise the possibility that the introduction of foreign DNA into the mammalian genome, either through retrotransposition or transgenesis, may be associated with parental imprinting that is not always erased and reset during meiosis.  相似文献   
5.
Oral drug delivery is a non-invasive and therefore a very convenient route of administration. Orally disintegrating dosage forms, like soluble films and (mini-)tablets, appear promising for use in the pediatric population. New guidance for the development of pediatric medicines has been published, which provides considerations on how pediatric products should be designed. However, most of the considerations leave a lot of room for interpretations. Bearing in mind the different aspects discussed in the latest guideline, the use of orally disintegrating films and tablets, in particular, small-sized tablets, is discussed and reflected upon by providing evidence from the scientific literature. The available dosage forms for children are various and examples of currently licensed products for use in the pediatric population were compiled. Aspects such as the appropriateness for pediatrics, the choice of excipients, the opportunities for modified drug release preparations or fixed-dose combinations, the acceptability and palatability, and also limitations were discussed with respect to the new dosage forms of orally disintegrating films and mini-tablets. This paper points out that innovation in pediatric medicines are planned and should be encouraged; however, supported by the regulatory guidance, only general considerations are provided. Nevertheless, the guideline summarizes multiple points to consider during the development of medicines for pediatric use. Considering the scientific evidence and the regulatory guidance, orally disintegrating dosage forms, like soluble films and (mini-)tablets, offer an innovative solution for pediatric drug delivery.KEY WORDS: children, orally disintegrating dosage forms, pediatric drug delivery, pediatrics, orodispersible films and tablets  相似文献   
6.
Reduced atmospheric oxygen concentration is beneficial to embryo development; however, optimal oxygen concentration for oocyte maturation remains undetermined. Likewise, there is no consensus of appropriate medium supplementation during maturation. The objective of this study was to determine whether oxygen tension (20% or 5% O2) and epidermal growth factor (EGF) affect oocyte metabolism and subsequent embryo development. Cumulus-oocyte complexes (COCs) were collected from 28-day-old equine chorionic gonadotropin (eCG) primed or unprimed F1 (C57BL/6xCBA) mice. COCs were matured in defined medium in one of four groups: 20% O2, 20% O2 + EGF, 5% O2, 5% O2 + EGF. In vivo matured COCs were also collected for analysis. COCs from unprimed mice, matured in 5% O2 +/- EGF or 20% O2 + EGF had higher metabolic rates than COCs matured in 20% O2 (P < 0.05). COCs from primed mice had higher metabolic rates when matured in the presence of EGF, regardless of oxygen tension (P < 0.01). Oxygen uptake and mitochondrial membrane potential were higher for in vivo matured oocytes and oocytes matured under 5% O2 compared to oocytes matured under 20% O2 (P < 0.05). Blastocyst formation was not different between maturation groups (primed or unprimed); however, embryo cell numbers were 20-45% significantly higher when COCs were matured at 5% O2 (P < 0.05). Results suggest that oocytes matured in physiological concentrations of oxygen have improved development and metabolic activity, more closely resembling in vivo maturation. These findings have implications for oocyte maturation in both clinical and research laboratories.  相似文献   
7.
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RATIONAL AND OBJECTIVES: Activation of fully differentiated vascular cells using angiogenic genes can lead to phenotypic changes resulting in formation of new blood vessels. We tested whether Ang-1 gene transfer to endothelial cells (EC) activates these cells. METHODS AND RESULTS: EC and SMC were transduced using retroviral or adenoviral vectors to produce Ang-1 or vascular endothelial growth factor (VEGF). EC Tie-2 receptor was phosphorilated by autologous secretion of Ang-1. Transduced EC and SMC sprouting capacity was tested using collagen embedded spheroids assay and capacity to produce arteriogenesis was tested in a hind limb model of ischemia. EC expressing Ang-1 in the presence of SMC expressing VEGF exhibited high levels of sprouting of the two cell types. Flow and numbers of arteries were increased after transduced cells implantation in vivo. CONCLUSIONS: Autologous secretion of Ang-1 by transduced EC resulted in Tie-2 activation and in the presence of SMC expressing VEGF resulted in coordinated sprouting in vitro and increase in flow and number of arteries in vivo.  相似文献   
9.

Background  

Rupture of the cap of a vulnerable plaque present in a coronary vessel may cause myocardial infarction and death. Cap rupture occurs when the peak cap stress exceeds the cap strength. The mechanical stress within a cap depends on the plaque morphology and the material characteristics of the plaque components. A parametric study was conducted to assess the effect of intima stiffness and plaque morphology on peak cap stress.  相似文献   
10.
Vast records of our everyday interests and concerns are being generated by our frequent interactions with the Internet. Here, we investigate how the searches of Google users vary across U.S. states with different birth rates and infant mortality rates. We find that users in states with higher birth rates search for more information about pregnancy, while those in states with lower birth rates search for more information about cats. Similarly, we find that users in states with higher infant mortality rates search for more information about credit, loans and diseases. Our results provide evidence that Internet search data could offer new insight into the concerns of different demographics.  相似文献   
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