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91.
Mutations in three different genes of phosphorylase kinase (Phk) subunits,
PHKA2, PHKB and PHKG2, can give rise to glycogen storage disease of the
liver. The autosomal-recessive, liver-specific variant of Phk deficiency is
caused by mutations in the gene encoding the testis/liver isoform of the
catalytic gamma subunit, PHKG2. To facilitate mutation detection and to
improve our understanding of the molecular evolution of Phk subunit
isoforms, we have determined the structure of the human PHKG2 gene. The
gene extends over 9.5 kilonucleotides and is divided into 10 exons;
positions of introns are highly conserved between PHKG2 and the gene of the
muscle isoform of the gamma subunit, PHKG1. The beginning of intron 2
harbors a highly informative GGT/GT microsatellite repeat, the first
polymorphic marker in the PHKG2 gene at human chromosome 16p11.2-p12.1.
Employing the gene sequence, we have identified homozygous
translation-terminating mutations, 277delC and Arg44ter, in the two
published cases of liver Phk deficiency who developed cirrhosis in
childhood. As liver Phk deficiency is generally a benign condition and
progression to cirrhosis is very rare, this finding suggests that PHKG2
mutations are associated with an increased cirrhosis risk.
相似文献
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MW Blom PR Bartel DK Sommers CH Van Der Meyden PJ Becker 《Fundamental & clinical pharmacology》1992,6(1):5-9
This study compares the effects of buspirone (5 mg), chlordiazepoxide (5 mg), hydroxyzine (10 mg) and placebo on psychomotor function and EEG, when taken thrice daily for a period of two weeks, with those after a single dose administration. Nine healthy volunteers participated in the study. The battery of psychomotor tests included peak velocity of saccadic eye movements (SEM), a Sternberg memory scanning and choice reaction time test (SMS-CRT) and critical flicker fusion frequency (CFFF). The peak velocity of saccadic eye movements was significantly impaired by the single dose of hydroxyzine (P = 0.03) in comparison to the multidose results. A similar comparison regarding buspirone only approached significance (P = 0.07). The SMS-CRT and CFFF did not reveal any difference between the multi and single dose regimens. Spectral analysis of the EEG did not distinguish between the multi and single dosage schedules regarding the respective drugs in the low doses administered. 相似文献
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P-31 MR spectroscopy of normal human brain and brain tumors 总被引:2,自引:0,他引:2
Hubesch B; Sappey-Marinier D; Roth K; Meyerhoff DJ; Matson GB; Weiner MW 《Radiology》1990,174(2):401-409
Image-guided phosphorus-31 magnetic resonance (MR)-localized image-selected in vivo spectroscopy was performed on normal human brain and brain tumors. Peak area ratios, absolute molar concentrations of metabolites, and pH were determined. T1 values in normal brain were measured. The most important finding was that the metabolite concentrations detectable with MR spectroscopy in brain tumors were reduced from 20% to 70%. Phosphomonoesters, phosphodiesters, and phosphocreatine (PCr) showed the greatest decreases, while inorganic phosphate (Pi) showed the least change. The PCr-Pi ratio was significantly reduced in tumors. The pH of brain tumors (7.12 +/- 0.03) was more alkaline than that of normal brain (6.99 +/- 0.01). The authors conclude that the metabolite concentrations and pH in human brain tumors differ significantly from those in normal brain. These differences may be ultimately useful in characterizing tumors in man. 相似文献
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Renate RJ de Groot-Besseling Theo JM Ruers Iris L Lamers-Elemans Cathy N Maass Robert MW de Waal Johan R Westphal 《BMC cancer》2006,6(1):149
Background
Upregulation of endogenous angiostatin levels may constitute a novel anti-angiogenic, and therefore anti-tumor therapy. In vitro, angiostatin generation is a two-step process, starting with the conversion of plasminogen to plasmin by plasminogen activators (PAs). Next, plasmin excises angiostatin from other plasmin molecules, a process requiring a donor of a free sulfhydryl group. In previous studies, it has been demonstrated that administration of PA in combination with the free sulfhydryl donor (FSD) agents captopril or N-acetyl cysteine, resulted in angiostatin generation, and anti-angiogenic and anti-tumour activity in murine models. 相似文献100.
Simonne Cohen Russell Conduit Steven W Lockley Shantha MW Rajaratnam Kim M Cornish 《Journal of Neurodevelopmental Disorders》2014,6(1)
Although there is evidence that significant sleep problems are common in children with autism spectrum disorder (ASD) and that poor sleep exacerbates problematic daytime behavior, such relationships have received very little attention in both research and clinical practice. Treatment guidelines to help manage challenging behaviors in ASD fail to mention sleep at all, or they present a very limited account. Moreover, limited attention is given to children with low-functioning autism, those individuals who often experience the most severe sleep disruption and behavioral problems. This paper describes the nature of sleep difficulties in ASD and highlights the complexities of sleep disruption in individuals with low-functioning autism. It is proposed that profiling ASD children based on the nature of their sleep disruption might help to understand symptom and behavioral profiles (or vice versa) and therefore lead to better-targeted interventions. This paper concludes with a discussion of the limitations of current knowledge and proposes areas that are important for future research. Treating disordered sleep in ASD has great potential to improve daytime behavior and family functioning in this vulnerable population. 相似文献