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Charles H. A. Snijders Rob A. Samson Ellen S. Hoekstra Thérèse Quellet J. David Miller Petra C. E. M. de Rooij-van der Goes A. J. M. Baar A. E. J. Dubois Henk F. Kauffman 《Mycopathologia》1996,135(2):119-128
In the European coastal dunes, marram grass (Ammophila arenaria) is planted in order to control sand erosion. In the years 1986 to 1991, workers on the Wadden islands in the Netherlands planting marram grass showed lesions of skin and mucous membranes, suggesting a toxic reaction. Fusarium culmorum dominated the mycoflora of those marram grass culms that were used for planting. This plant material had been cut and stored for more than one week in the open. The Fusarium toxin deoxynivalenol (DON) was detected in the suspect marram grass culms. Isolated F. culmorum strains were able to produce DON in vitro in liquid culture as well as in experimentally inoculated wheat heads. Pathogenicity tests, toxin test as well as RAPD analysis showed that the F. culmorum strains were not specialized for marram grass but may form part of the West-European F. culmorum population infecting cereals and grasses. Storage on old sand-dunes with plant debris may have led to the high occurrence of F. culmorum and contamination with DON. Marram grass culms should be obtained from young plantings on dunes on the seaward slopes and cut culms should not be stored. 相似文献
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Mikael?Erlandsson Mattias?H?llbrinkEmail author 《International journal of peptide research and therapeutics》2005,11(4):261-265
The use of powdered metallic zinc in acidic solution for the reduction of disulfide bonds in peptides and proteins has been
investigated. The method has several advantages over the traditional mercapto based reducing methods currently used; the reducing
agent is readily available and inexpensive; reduction can be performed in weakly acidic solutions of water and/or acetonitrile;
work up simply consists of a centrifugation step followed by pipeting the supernatant from the metal pellet, thereby greatly
diminishing the risk of reoxidation as a more elaborate work up procedure could result in. As no mercapto compounds are added,
there is no risk that the reducing agent will interfere in subsequent modification of the thiol functionality. Disulfides
in a model peptide are reduced within 5 min in any mixture of water/acetonitrile containing 1% TFA, all disulfides in insulin
is reduced within 1 h in any mixture of water/acetonitrile containing 5% acetic acid. To stress the convenience of the metallic
zinc reduction method, the resulting thiol compound was subjected to two commonly employed reactions in peptide chemistry:
Cys(Npys) directed disulfide formation (70% yield) and native chemical ligation between the reduced model peptide and Boc-Ala-p-metylthiobenzyl ester (65% yield of the ligation product plus disulfide formation between Cys and p-thiocresol). 相似文献
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Susanne?Abelin?T?rnblom Holger?Maul Aurelija?KlimaviciuteEmail author Robert?E?Garfield Birgitta?Bystr?m Anders?Malmstr?m Gunvor?Ekman-Ordeberg 《Reproductive biology and endocrinology : RB&E》2005,3(1):33
Background
Preterm birth is the primary cause of the neonatal mortality and morbidity. There will be no preterm birth without a cervical softening. Nitric oxide (NO) is shown to be a mediator of term cervical ripening. The aim of this study was to investigate mRNA expression of the three isomers of NO synthases (NOS) and to identify them by immunohistochemistry in the human cervix at preterm birth compared to term. 相似文献5.
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Reaux-Le Goazigo A Alvear-Perez R Zizzari P Epelbaum J Bluet-Pajot MT Llorens-Cortes C 《American journal of physiology. Endocrinology and metabolism》2007,292(1):E7-15
Apelin is a bioactive peptide recently identified as the endogenous ligand of the human orphan G protein-coupled receptor APJ. The presence of apelin-immunoreactive nerve fibers, together with the detection of apelin receptor mRNA in the parvocellular part of the paraventricular nucleus and the stimulatory action of apelin on corticotropin-releasing hormone release, indicate that apelin modulates adrenocorticotropin (ACTH) release via an indirect action on the hypothalamus. However, a direct action of apelin in the anterior pituitary cannot be excluded. Here, we provided evidence for the existence of an apelinergic system within the adult male rat pituitary gland. Double immunofluorescence staining indicated that apelin is highly coexpressed in the anterior pituitary, mainly in corticotrophs (96.5 +/- 0.3%) and to a much lower extent in somatotropes (3.2 +/- 0.2%). Using in situ hybridization combined with immunohistochemistry, a high expression of apelin receptor mRNA was also found in corticotrophs, suggesting a local interaction between apelin and ACTH. In an ex vivo perifusion system of anterior pituitaries, apelin 17 (K17F, 10(-6) M) significantly increased basal ACTH release by 41%, whereas apelin 10 (R10F, 10(-6) M), an inactive apelin fragment, was ineffective. In addition, K17F but not R10F induced a dose-dependent increase in K(+)-evoked ACTH release, with maximal increase being observed for a 10(-6) M concentration. Taken together, these data outline the potential role of apelin as an autocrine/paracrine-acting peptide on ACTH release and provide morphological and neuroendocrine basis for further studies that explore the physiological role of apelin in the regulation of anterior pituitary functions. 相似文献
7.
Skogh T 《Arthritis research & therapy》2005,7(6):230-232
The introduction of tests recognizing 'anti-citrullinated protein antibodies' (ACPA) has caused a revolution in rheumatology.
Immunization against citrullinated proteins is a feature almost unique for rheumatoid arthritis, although ACPA may occur long
before the onset of symptoms. Even if the presence of ACPA does not seem to reveal a distinct arthritis phenotype at symptom
onset, it predicts an aggressive disease course with unfavourable outcome. Despite the very high diagnostic specificity for
rheumatoid arthritis, ACPA-positivity does not always accord with a traditional diagnosis of rheumatoid arthritis at clinical
presentation. However, even when these patients are judged to suffer from mild undifferentiated arthritis, they call for follow-up
and special attention by rheumatologists. 相似文献
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Clémentine Schilte Frédérik Staikovsky Thérèse Couderc Yoann Madec Florence Carpentier Somar Kassab Matthew L. Albert Marc Lecuit Alain Michault 《PLoS neglected tropical diseases》2013,7(3)