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1.
Survival of Male Patients with Incontinentia Pigmenti Carrying a Lethal Mutation Can Be Explained by Somatic Mosaicism or Klinefelter Syndrome 总被引:2,自引:0,他引:2 下载免费PDF全文
The International IP Consortium 《American journal of human genetics》2001,69(6):1210-1217
Incontinentia pigmenti (IP), or "Bloch-Sulzberger syndrome," is an X-linked dominant disorder characterized by abnormalities of skin, teeth, hair, and eyes; skewed X-inactivation; and recurrent miscarriages of male fetuses. IP results from mutations in the gene for NF-kappaB essential modulator (NEMO), with deletion of exons 4-10 of NEMO accounting for >80% of new mutations. Male fetuses inheriting this mutation and other "null" mutations of NEMO usually die in utero. Less deleterious mutations can result in survival of males subjects, but with ectodermal dysplasia and immunodeficiency. Male patients with skin, dental, and ocular abnormalities typical of those seen in female patients with IP (without immunodeficiency) are rare. We investigated four male patients with clinical hallmarks of IP. All four were found to carry the deletion normally associated with male lethality in utero. Survival in one patient is explained by a 47,XXY karyotype and skewed X inactivation. Three other patients possess a normal 46,XY karyotype. We demonstrate that these patients have both wild-type and deleted copies of the NEMO gene and are therefore mosaic for the common mutation. Therefore, the repeat-mediated rearrangement leading to the common deletion does not require meiotic division. Hypomorphic alleles, a 47,XXY karyotype, and somatic mosaicism therefore represent three mechanisms for survival of males carrying a NEMO mutation. 相似文献
2.
Pyranosyl chlorides prepared in situ from tri-O-benzyl-D-galactal and TolSCl react with silyl enol ethers, allyltrimethylsilane, and vinyl ethers to give a mixture of beta-C-galacto and alpha-C-talopyranosides in a ratio of 19:1. 相似文献
3.
Honzatko A Brichac J Murphy TC Reberg A Kubátová A Smoliakova IP Picklo MJ 《Free radical biology & medicine》2005,39(7):913-924
Trans-4-hydroxy-2-nonenal (HNE) is a product of lipid peroxidation with many cellular effects. HNE possesses a stereogenic center at the C4 carbon that influences the metabolism and alkylation targets of HNE. We tested the hypothesis that rat brain mitochondria metabolize HNE in an enantioselective manner after exposure to racemic HNE. The study of HNE chirality, however, is hindered by the lack of facile methods to chromatographically resolve (R)-HNE and (S)-HNE. We used a chiral hydrazine, (S)-carbidopa, as a derivatization reagent to form diastereomers with (R)-HNE and (S)-HNE that were separated by reverse-phase HPLC. After exposure to racemic HNE, rat brain mitochondria metabolized HNE enantioselectively with a higher rate of (R)-HNE metabolism. By using the purified enantiomers of HNE, we found that this enantioselective metabolism of HNE was the result of higher rates of enzymatic oxidation of (R)-HNE by aldehyde dehydrogenases compared to (S)-HNE. Conjugation of HNE to glutathione was a minor metabolic pathway and was not enantioselective. These studies demonstrate that the chirality of HNE affects its mitochondrial metabolism and potentially other processes in the central nervous system. 相似文献
4.
S. LUYSSAERT P. CIAIS S. L. PIAO E.‐D. SCHULZE M. JUNG S. ZAEHLE M. J. SCHELHAAS M. REICHSTEIN G. CHURKINA D. PAPALE G. ABRIL C. BEER J. GRACE D. LOUSTAU G. MATTEUCCI F. MAGNANI G. J. NABUURS H. VERBEECK M. SULKAVA G. R.
Van Der WERF I. A. JANSSENS members of the CARBOEUROPE‐IP SYNTHESIS TEAM 《Global Change Biology》2010,16(5):1429-1450
We present a new synthesis, based on a suite of complementary approaches, of the primary production and carbon sink in forests of the 25 member states of the European Union (EU‐25) during 1990–2005. Upscaled terrestrial observations and model‐based approaches agree within 25% on the mean net primary production (NPP) of forests, i.e. 520±75 g C m?2 yr?1 over a forest area of 1.32 × 106 km2 to 1.55 × 106 km2 (EU‐25). New estimates of the mean long‐term carbon forest sink (net biome production, NBP) of EU‐25 forests amounts 75±20 g C m?2 yr?1. The ratio of NBP to NPP is 0.15±0.05. Estimates of the fate of the carbon inputs via NPP in wood harvests, forest fires, losses to lakes and rivers and heterotrophic respiration remain uncertain, which explains the considerable uncertainty of NBP. Inventory‐based assessments and assumptions suggest that 29±15% of the NBP (i.e., 22 g C m?2 yr?1) is sequestered in the forest soil, but large uncertainty remains concerning the drivers and future of the soil organic carbon. The remaining 71±15% of the NBP (i.e., 53 g C m?2 yr?1) is realized as woody biomass increments. In the EU‐25, the relatively large forest NBP is thought to be the result of a sustained difference between NPP, which increased during the past decades, and carbon losses primarily by harvest and heterotrophic respiration, which increased less over the same period. 相似文献
5.
Nucleotide sequence of the genes for tryptophan synthase in Pseudomonas aeruginosa 总被引:17,自引:0,他引:17
We have determined the DNA sequence of the two adjacent genes for the alpha
and beta chains of tryptophan synthase in Pseudomonas aeruginosa, along
with 34 5'-flanking and 799 3'-flanking base pairs. The gene order is trpBA
as predicted from earlier genetic studies, and the two cistrons overlap by
4 bp; a ribosome binding site for the second gene is evident in the coding
sequence of the first gene. We have also determined the location of three
large deletions eliminating portions of each gene. A detailed comparison of
the deduced P. aeruginosa amino acid sequence with those published for E.
coli, Bacillus subtilis, and Saccharomyces cerevisiae shows much similarity
throughout the beta and most of the alpha subunit. Most of the residues
implicated by chemical modification or mutation as being critical for
enzymatic activity are conserved, along with many others, suggesting that
three-dimensional structure has remained largely constant during evolution.
We also report the construction of a recombinant plasmid that overproduces
a slightly modified alpha subunit from P. aeruginosa that can form a
functionally effective multimer with normal E. coli beta 2 subunit in vivo.
相似文献
6.
A G Prikhod'ko Iu P Efimitsev V V Bazhenov N B Vasina I A Sankin N E Smoliakova 《Vestnik rentgenologii i radiologii》1991,(4):38-43
A total of 106 patients suffering from tumors and inflammatory diseases of the head and neck were investigated. CT was performed in axial and frontal projections using a method of intravenous contrast image enhancement. The purpose of CT was to reveal an abnormal lesion, to detect its initial site, spreading, to make differential diagnosis, and to evaluate therapeutic results. Some limitations of CT in differential diagnosis of small-size tumors were observed. CT can be used for differential diagnosis of tumors and inflammatory processes in the accessory nasal sinuses. CT results were important for a choice of therapeutic methods, radiation therapy design, assessment of efficacy of surgical and radiation therapy, and the detection of tumor recurrences. 相似文献
7.
Structure and regulation of the anthranilate synthase genes in Pseudomonas aeruginosa: II. Cloning and expression in Escherichia coli 总被引:7,自引:0,他引:7
Crawford IP; Wilde A; Yelverton EM; Figurski D; Hedges RW 《Molecular biology and evolution》1986,3(5):449-458
The genes for the large and small subunits of anthranilate synthase (trpE
and trpG, respectively) have been cloned from Pseudomonas aeruginosa PAC174
into E. coli by R-prime formation with the broad-host- range plasmid
R68.44. Sequential subcloning into plasmid vectors reduced the active
Pseudomonas DNA fragment to a length of 3.1 kb. We obtained evidence that
this region contains the promoter for its own expression and retains a
vestigial regulatory response to tryptophan scarcity or excess.
相似文献
8.
ANSON V. KOEHLER JOHN M. PEARCE PAUL L. FLINT J. CHRISTIAN FRANSON HON S. IP 《Molecular ecology》2008,17(21):4754-4762
The role of migratory birds in the movement of the highly pathogenic (HP) avian influenza H5N1 remains a subject of debate. Testing hypotheses regarding intercontinental movement of low pathogenic avian influenza (LPAI) viruses will help evaluate the potential that wild birds could carry Asian-origin strains of HP avian influenza to North America during migration. Previous North American assessments of LPAI genetic variation have found few Asian reassortment events. Here, we present results from whole-genome analyses of LPAI isolates collected in Alaska from the northern pintail (Anas acuta), a species that migrates between North America and Asia. Phylogenetic analyses confirmed the genetic divergence between Asian and North American strains of LPAI, but also suggested inter-continental virus exchange and at a higher frequency than previously documented. In 38 isolates from Alaska, nearly half (44.7%) had at least one gene segment more closely related to Asian than to North American strains of LPAI. Additionally, sequences of several Asian LPAI isolates from GenBank clustered more closely with North American northern pintail isolates than with other Asian origin viruses. Our data support the role of wild birds in the intercontinental transfer of influenza viruses, and reveal a higher degree of transfer in Alaska than elsewhere in North America. 相似文献
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