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31.
Several authors have attempted to construct a phenotype map for duplications of different portions of chromosome 18 to identify a possible critical region (CR) for Edwards Syndrome. Partial duplications of 18q have been reported in the literature involving the distal CR in patients with some clinical features of Edwards Syndrome. Here, we describe a phenotypically normal male with a large duplication on chromosome 18 that involves the proposed distal CR. The lack of clinical features is remarkable, except for pathological semen analysis, which suggests that terminal 17.4 Mb of 18q do not contain the Edwards Syndrome CR. Alternatively, unknown modifier factors or undetected somatic mosaicism might cause incomplete penetrance of this duplication.  相似文献   
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Tacrolimus (FK506) is a hydrophobic immunosuppressive agent that rapidly penetrates the plasmatic membrane and inhibits the signal transduction cascade of T lymphocytes. The objective of this study was the characterization of liposomal FK506 with surfactant-like phospholipids to be administered intratracheally after lung transplantation or in inflammatory lung diseases. We evaluated the optimal incorporation of FK506 in dipalmitoylphosphatidylcholine (DPPC) and DPPC/1-palmitoyl-2-oleoylphosphatidylglycerol (POPG) monolayers and bilayers and the effects of FK506 on the physical properties of DPPC and DPPC/POPG (8:2 w/w) vesicles. In addition, we assessed the immunosuppressive effects of surfactant-like phospholipid vesicles containing different amounts of FK506 on T-cell proliferation and interleukin 2 production. From surface pressure measurements of FK506/DPPC and FK506/DPPC/POPG mixed monolayers, we determined that FK506 was embedded into these monolayers up to an FK506 concentration of about 0.4 mol %. Beyond this concentration, FK506 was not quantitatively incorporated into the monolayer, suggesting possible concentration-dependent aggregation of tacrolimus. The incorporation of FK506 into DPPC monolayers, at concentrations 相似文献   
34.
The prenatal cytogenetic study of an amniotic fluid sample of a 39-year-old female showed one X chromosome with a fragment of extra material in the short arm. The G-band pattern suggested that the extra material could be the long arm of an X chromosome. Several complementary studies were performed in order to better clarify the origin of the material. These studies included parental karyotypes, microsatellite typing and comparative genomic hybridization (CGH). The results obtained allowed us to conclude that the derivative chromosome arose de novo as a recombinant X chromosome with duplication of Xq and partial deletion of Xp. Once informed, the parents decided to continue with the pregnancy, after which a healthy girl was born with no apparent disorders.  相似文献   
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Accretion rates of muscle protein are elevated in normal neonates, but this anabolic drive decreases with maturation. As this change occurs, it is not known whether development also influences muscle protein catabolism induced by sepsis. We hypothesize that protein degradation in skeletal muscle induced by endotoxemia becomes more severe as the neonate develops. Fasted 7- and 26-day-old pigs were infused for 8 h with LPS (0 and 10 μg·kg(-1)·h(-1)), while plasma amino acids (AA), 3-methylhistidine (3-MH), and α-actin concentrations and muscle protein degradation signal activation were determined (n = 5-7/group/age). Plasma full-length α-actin was greater in 7- than 26-day-old pigs, suggesting a higher baseline protein turnover in neonatal pigs. LPS increased plasma total AA, 3-MH, and full-length and cleaved α-actin in 26- than in 7-day-old pigs. In muscle of both age groups, LPS increased AMPK and NF-κB phosphorylation, the abundances of activated caspase 3 and E-3 ligases MuRF1 and atrogin1, as well as the abundance of cleaved α-actin, suggesting activation of muscle proteolysis by endotoxin in muscle. LPS decreased Forkhead box 01 (Fox01) and Fox04 phosphorylation and increased procaspase 3 abundance in muscle of 26-day-old pigs despite the lack of effect of LPS on PKB phosphorylation. The results suggest that skeletal muscle in healthy neonatal pigs maintains high baseline degradation signal activation that cannot be enhanced by endotoxin, but as maturation advances, the effect of LPS on muscle protein catabolism manifests its severity.  相似文献   
37.
Orogastric tube feeding is indicated for neonates with impaired ability to ingest and can be administered by intermittent bolus or continuous schedule. Our aim was to determine whether feeding modalities affect muscle protein deposition and to identify mechanisms involved. Neonatal pigs were overnight fasted (FAS) or fed the same amount of food continuously (CON) or intermittently (INT; 7 × 4 h meals) for 29 h. For 8 h, between hours 20 and 28, pigs were infused with [(2)H(5)]phenylalanine and [(2)H(2)]tyrosine, and amino acid (AA) net balances were measured across the hindquarters. Insulin, branched-chain AA, phenylalanine, and tyrosine arterial concentrations and whole body phenylalanine and tyrosine fluxes were greater for INT after the meal than for CON or FAS. The activation of signaling proteins leading to initiation of mRNA translation, including eukaryotic initiation factor (eIF)4E·eIF4G complex formation in muscle, was enhanced by INT compared with CON feeding or FAS. Signaling proteins of protein degradation were not affected by feeding modalities except for microtubule-associated protein light chain 3-II, which was highest in the FAS. Across the hindquarters, AA net removal increased for INT but not for CON or FAS, with protein deposition greater for INT. This was because protein synthesis increased following feeding for INT but remained unchanged for CON and FAS, whereas there was no change in protein degradation across any dietary treatment. These results suggest that muscle protein accretion in neonates is enhanced with intermittent bolus to a greater extent than continuous feeding, mainly by increased protein synthesis.  相似文献   
38.
Silene ciliata Poiret is a small perennial that presents several ploidy levels and inhabits the mountain ranges of the European Mediterranean basin. Recent studies have shown evidence of local adaptation in populations located across an altitudinal gradient in Sierra de Guadarrama (Central Spain) at the species’ southernmost distribution limit. In this study, we assessed whether the existence of local adaptation in these populations was related to differences in karyological features (ploidy level or chromosome number modification) or in nuclear DNA amount. Optical microscope (phase contrast and epifluorescence after DAPI staining) and flow cytometry were used to estimate the ploidy level and genome size of several family lines in three populations across the altitude gradient. With a sampling three times higher than usual in genome size assessments, all individuals showed a constant diploid set (2n = 24), so that polyploidy or other chromosome number modifications were discarded. The small genome size found (mean ± SD; 2C = 1.76 ± 0.06 pg) was within the range of those found in other Silene species. Significant differences in genome size were found when the three populations of S. ciliata were compared. The largest genome size found at the intermediate population may be associated to lower environmental stress at the mid elevation, in line with the recent studies in this area.  相似文献   
39.
A new class of p38α inhibitors based on a biaryl-triazolopyridine scaffold was investigated. X-ray crystallographic data of the initial lead compound cocrystallised with p38α was crucial in order to uncover a unique binding mode of the inhibitor to the hinge region via a pair of water molecules. Synthesis and SAR was directed towards the improvement of binding affinity, as well as ADME properties for this new class of p38α inhibitors and ultimately afforded compounds showing good in vivo efficacy.  相似文献   
40.
A series of aminopyrazines as inhibitors of Syk kinase activity and showing inhibition of LAD2 cells degranulation is described. Optimization of the carboxamide motif with aminomethylpiperidines provided high potency inhibiting Syk but low cellular activity. Amides of cis and trans adamantanol showed good inhibitory activity against Syk as well as remarkable activity in LAD2 cells degranulation assay.  相似文献   
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