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341.
Scorpio A Blank TE Day WA Chabot DJ 《Cellular and molecular life sciences : CMLS》2006,63(19-20):2237-2248
Anthrax has been a major cause of death in grazing animals and an occasional cause of death in humans for thousands of years. Since the late 1800s there has been an exceptional international history of anthrax vaccine development. Due to animal vaccinations, the rate of infection has dropped dramatically. Anthrax vaccines have progressed from uncharacterized whole-cell vaccines in 1881, to pXO2-negative spores in the 1930s, to culture filtrates absorbed to aluminum hydroxide in 1970, and likely to recombinant protective antigen in the near future. Each of these refinements has increased safety without significant loss of efficacy. The threat of genetically engineered, antibiotic and vaccine resistant strains of Bacillus anthracis is fueling hypothesis-driven research and global techniques--including genomics, proteomics and transposon site hybridization--to facilitate the discovery of novel vaccine targets. This review highlights historical achievements and new developments in anthrax vaccine research. 相似文献
342.
Structural and biological aspects of carotenoid cleavage 总被引:1,自引:0,他引:1
Apo-carotenoid compounds such as retinol (vitamin A) are involved in a variety of cellular processes and are found in all kingdoms of life. Instead of being synthesized from small precursors, they are commonly produced by oxidative cleavage and subsequent modification of larger carotenoid compounds. The cleavage reaction is catalyzed by a family of related enzymes, which convert specific substrate double bonds to the corresponding aldehydes or ketones. The individual family members differ in their substrate preference and the position of the cleaved double bond, giving rise to a remarkable number of products starting from a limited number of carotenoid substrate molecules. The recent determination of the structure of a member of this family has provided insight into the reaction mechanism, showing how substrate specificity is achieved. This review will focus on the biochemistry of carotenoid oxygenases and the structural determinants of the cleavage reaction. 相似文献
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345.
Snake envenomation is a socio-medical problem of considerable magnitude. About 2.5 million people are bitten by snakes annually,
more than 100,000 fatally. However, although bites can be deadly, snake venom is a natural biological resource that contains
several components of potential therapeutic value. Venom has been used in the treatment of a variety of pathophysiological
conditions in Ayurveda, homeopathy and folk medicine. With the advent of biotechnology, the efficacy of such treatments has
been substantiated by purifying components of venom and delineating their therapeutic properties. This review will focus on
certain snake venom components and their applications in health and disease.
Received 6 July 2006; received after revision 14 August 2006; accepted 28 September 2006 相似文献
346.
Phytanic acid is a branched-chain fatty acid that accumulates in a variety of metabolic disorders. High levels of phytanic
acid found in patients can exceed the millimolar range and lead to severe symptoms. Degradation of phytanic acid takes place
by α-oxidation inside the peroxisome. A deficiency of its breakdown, leading to elevated levels, can result from either a
general peroxisomal dysfunction or from a defect in one of the enzymes involved in α-oxidation. Research on Refsum disease,
belonging to the latter group of disorders and characterized by a deficiency of the first enzyme of α-oxidation, has extended
our knowledge of phytanic acid metabolism and pathology of the disease greatly over the past few decades. This review will
centre on this research on phytanic acid: its origin, the mechanism by which its α-oxidation takes place, its role in human
disease and the way it is produced from phytol.
Received 4 October 2005; received after revision 24 February 2006; accepted 26 April 2006 相似文献
347.
Truncating mutations in the Fanconi anemia J gene BRIP1 are low-penetrance breast cancer susceptibility alleles 总被引:21,自引:0,他引:21
Seal S Thompson D Renwick A Elliott A Kelly P Barfoot R Chagtai T Jayatilake H Ahmed M Spanova K North B McGuffog L Evans DG Eccles D;Breast Cancer Susceptibility Collaboration 《Nature genetics》2006,38(11):1239-1241
We identified constitutional truncating mutations of the BRCA1-interacting helicase BRIP1 in 9/1,212 individuals with breast cancer from BRCA1/BRCA2 mutation-negative families but in only 2/2,081 controls (P = 0.0030), and we estimate that BRIP1 mutations confer a relative risk of breast cancer of 2.0 (95% confidence interval = 1.2-3.2, P = 0.012). Biallelic BRIP1 mutations were recently shown to cause Fanconi anemia complementation group J. Thus, inactivating truncating mutations of BRIP1, similar to those in BRCA2, cause Fanconi anemia in biallelic carriers and confer susceptibility to breast cancer in monoallelic carriers. 相似文献
348.
349.
Huntington’s disease: from huntingtin function and dysfunction to therapeutic strategies 总被引:3,自引:0,他引:3
Borrell-Pagès M Zala D Humbert S Saudou F 《Cellular and molecular life sciences : CMLS》2006,63(22):2642-2660
Huntington’s disease (HD) is a neurodegenerative disorder that usually starts in middle age and is characterized by involuntary
movements (chorea), personality changes and dementia, leading to death within 10–20 years. The defective gene in HD contains
a trinucleotide CAG repeat expansion within its coding region that expresses a polyglutamine repeat in the protein huntingtin.
Together with the characteristic formation of aggregates in HD, aberrant protein interactions and several post-translational
modifications affect huntingtin during disease progression and lead to the dysfunction and death of selective neurons in the
brains of patients. The exact molecular mechanisms by which mutant huntingtin induces cell death are not completely understood
but may involve the gain of new toxic functions and the loss of the beneficial properties of huntingtin. This review focuses
on the cellular functions in which huntingtin is involved and how a better understanding of pathogenic pathways can lead to
new therapeutic approaches.
Received 24 May 2006; received after revision 5 July 2006; accepted 23 August 2006 相似文献
350.
传统的正向遗传学主要用于克隆表型或功能已确定的基因。转座子标签突变体可用随机标签法从带有活性转座子的自交后代中筛选得到,或用定向标签法从杂交一代中筛选得到,即用目的基因的隐性突变统合体与具高度活性转座号的统合体杂交,极大多数的FI个体为正常表型,但其中会有极少量的表现隐性性状的转庄子插入突变体。正向基因标签和克隆法在利用异源和低拷贝数品系时尤其有用。采用反向fCR或热不对称交替PCR(TAIL-PCR)且很容易从单拷贝或低拷贝数品系中获得插入于两侧的基因组序列。TAIL-PCR由三轮连续的半巢式PCR组成,所… 相似文献