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691.
Huet J Wyckmans J Wintjens R Boussard P Raussens V Vandenbussche G Ruysschaert JM Azarkan M Looze Y 《Cellular and molecular life sciences : CMLS》2006,63(24):3042-3054
Two chitinases, able to use tetra-N-acetylglucosamine, chitin and chitosan as substrates, were characterized after purification from Carica papaya latex. The complete amino acid sequence of the major form and about 40% of the minor one were determined through proteolytic
digestions and mass spectroscopy analysis. Sequencing demonstrated that both papaya chitinases are members of the family 19
of glycosyl hydrolases (GH19). Based on the known 3-D structures of other members of family GH19, it was expected that papaya
chitinases would adopt all-alpha structures. However, circular dichroism and infrared spectroscopy indicated, for the papaya
chitinases, a content of 15–20% of extended structures besides the expected 40% of alpha helices. Since the fully sequenced
papaya chitinase contains a large number of proline residues the possibility that papaya chitinase contains polyproline II
stretches was examined in the context of their resistance against proteolytic degradation.
Received 11 July 2006; received after revision 13 October 2006; accepted 25 October 2006 相似文献
692.
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
693.
Kramer J Böhrnsen F Lindner U Behrens P Schlenke P Rohwedel J 《Cellular and molecular life sciences : CMLS》2006,63(5):616-626
Microfracture of subchondral bone results in intrinsic repair of cartilage defects. Stem or progenitor cells from bone marrow
have been proposed to be involved in this regenerative process. Here, we demonstrate for the first time that mesenchymal stem
(MS) cells can in fact be recovered from matrix material saturated with cells from bone marrow after microfracture. This also
introduces a new technique for MS cell isolation during arthroscopic treatment. MS cells were phenotyped using specific cell
surface antibodies. Differentiation of the MS cells into the adipogenic, chondrogenic and osteogenic lineage could be demonstrated
by cultivation of MS cells as a monolayer, as micromass bodies or mesenchymal microspheres. This study demonstrates that MS
cells can be attracted to a cartilage defect by guidance of a collagenous matrix after perforating subchondral bone. Protocols
for application of MS cells in restoration of cartilage tissue include an initial invasive biopsy to obtain the MS cells and
time-wasting in vitro proliferation and possibly differentiation of the cells before implantation. The new technique already includes attraction
of MS cells to sites of cartilage defects and therefore may overcome the necessity of in vitro proliferation and differentiation of MS cells prior to transplantation.
Received 3 November 2005; received after revision 15 December 2005; accepted 4 January 2006 相似文献
694.
695.
Pappas G Panagopoulou P Christou L Akritidis N 《Cellular and molecular life sciences : CMLS》2006,63(19-20):2229-2236
Brucella has traditionally been considered a biological weapon. It was the subject of extensive offensive research in the past, and still belongs to category B pathogens on most lists. Its propensity for airborne transmission and induction of chronic debilitating disease requiring combined antibiotic regimens for treatment, its abundance around the world and its vague clinical characteristics defying rapid clinical diagnosis are some of the characteristics that apply to the pathogen's weapons potential. Yet minimal mortality, availability of treatment options, protracted inoculation period and the emergence of new, more virulent potential weapons means that its inclusion among agents of bioterrorism is nowadays mainly of historical significance. Nevertheless, in the interest of literacy and of avoiding panic, physicians and the public both should be aware of the most common zoonosis worldwide. 相似文献
696.
Human skin is permanently exposed to microorganisms, but rarely infected. One reason for this natural resistance might be
the existence of a ‘chemical barrier’ consisting in constitutively and inducibly produced antimicrobial peptides and proteins
(AMPs). Many of these AMPs can be induced in vitro by proinflammatory cytokines or bacteria. Apart from being expressed in vivo in inflammatory lesions, some AMPs are also focally expressed in skin in the absence of inflammation. This suggests that
non-inflammatory stimuli of endogenous and/or exogenous origin can also stimulate AMP synthesis without inflammation. Such
mediators might be ideal ‘immune stimulants’ to induce only the innate antimicrobial skin effector molecules without causing
inflammation.
Received 9 August 2005; received after revision 21 October 2005; accepted 16 November 2005 相似文献
697.
Skin barrier function and allergic risk 总被引:11,自引:0,他引:11
Hudson TJ 《Nature genetics》2006,38(4):399-400
698.
Common loss-of-function variants of the epidermal barrier protein filaggrin are a major predisposing factor for atopic dermatitis 总被引:21,自引:0,他引:21
Palmer CN Irvine AD Terron-Kwiatkowski A Zhao Y Liao H Lee SP Goudie DR Sandilands A Campbell LE Smith FJ O'Regan GM Watson RM Cecil JE Bale SJ Compton JG DiGiovanna JJ Fleckman P Lewis-Jones S Arseculeratne G Sergeant A Munro CS El Houate B McElreavey K Halkjaer LB Bisgaard H Mukhopadhyay S McLean WH 《Nature genetics》2006,38(4):441-446
Atopic disease, including atopic dermatitis (eczema), allergy and asthma, has increased in frequency in recent decades and now affects approximately 20% of the population in the developed world. Twin and family studies have shown that predisposition to atopic disease is highly heritable. Although most genetic studies have focused on immunological mechanisms, a primary epithelial barrier defect has been anticipated. Filaggrin is a key protein that facilitates terminal differentiation of the epidermis and formation of the skin barrier. Here we show that two independent loss-of-function genetic variants (R510X and 2282del4) in the gene encoding filaggrin (FLG) are very strong predisposing factors for atopic dermatitis. These variants are carried by approximately 9% of people of European origin. These variants also show highly significant association with asthma occurring in the context of atopic dermatitis. This work establishes a key role for impaired skin barrier function in the development of atopic disease. 相似文献
699.
Greenway MJ Andersen PM Russ C Ennis S Cashman S Donaghy C Patterson V Swingler R Kieran D Prehn J Morrison KE Green A Acharya KR Brown RH Hardiman O 《Nature genetics》2006,38(4):411-413
We recently identified angiogenin (ANG) as a candidate susceptibility gene for amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder characterized by adult-onset loss of motor neurons. We now report the finding of seven missense mutations in 15 individuals, of whom four had familial ALS and 11 apparently 'sporadic' ALS. Our findings provide further evidence that variations in hypoxia-inducible genes have an important role in motor neuron degeneration. 相似文献
700.
Gandhi TK Zhong J Mathivanan S Karthick L Chandrika KN Mohan SS Sharma S Pinkert S Nagaraju S Periaswamy B Mishra G Nandakumar K Shen B Deshpande N Nayak R Sarker M Boeke JD Parmigiani G Schultz J Bader JS Pandey A 《Nature genetics》2006,38(3):285-293
We present the first analysis of the human proteome with regard to interactions between proteins. We also compare the human interactome with the available interaction datasets from yeast (Saccharomyces cerevisiae), worm (Caenorhabditis elegans) and fly (Drosophila melanogaster). Of >70,000 binary interactions, only 42 were common to human, worm and fly, and only 16 were common to all four datasets. An additional 36 interactions were common to fly and worm but were not observed in humans, although a coimmunoprecipitation assay showed that 9 of the interactions do occur in humans. A re-examination of the connectivity of essential genes in yeast and humans indicated that the available data do not support the presumption that the number of interaction partners can accurately predict whether a gene is essential. Finally, we found that proteins encoded by genes mutated in inherited genetic disorders are likely to interact with proteins known to cause similar disorders, suggesting the existence of disease subnetworks. The human interaction map constructed from our analysis should facilitate an integrative systems biology approach to elucidating the cellular networks that contribute to health and disease states. 相似文献