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121.
122.
Orianna Bretschger Anna Obraztsova Carter A. Sturm In Seop Chang Yuri A. Gorby Samantha B. Reed David E. Culley Catherine L. Reardon Soumitra Barua Margaret F. Romine Jizhong Zhou Alexander S. Beliaev Rachida Bouhenni Daad Saffarini Florian Mansfeld Byung-Hong Kim James K. Fredrickson Kenneth H. Nealson 《Applied and environmental microbiology》2008,74(2):553
123.
Leo AB Joosten Erik Lubberts Monique MA Helsen Tore Saxne Christina JJ Coenen-de Roo Dick Heinegård Wim B van den Berg 《Arthritis research & therapy》1999,1(1):81-11
Destruction of cartilage and bone are hallmarks of human rheumatoid arthritis (RA), and controlling these erosive processes
is the most challenging objective in the treatment of RA. Systemic interleukin-4 treatment of established murine collagen-induced
arthritis suppressed disease activity and protected against cartilage and bone destruction. Reduced cartilage pathology was
confirmed by both decreased serum cartilage oligomeric matrix protein (COMP) and histological examination. In addition, radiological
analysis revealed that bone destruction was also partially prevented. Improved suppression of joint swelling was achieved
when interleukin-4 treatment was combined with low-dose prednisolone treatment. Interestingly, synergistic reduction of both
serum COMP and inflammatory parameters was noted when low-dose interleukin-4 was combined with prednisolone. Systemic treatment
with interleukin-4 appeared to be a protective therapy for cartilage and bone in arthritis, and in combination with prednisolone
at low dosages may offer an alternative therapy in RA. 相似文献
124.
All-trans-retinol reacts with methyl (2,3,4-tri-O-acetyl-1-bromo-1-deoxy-beta-D-glucopyran)uronate in the presence of Ag2CO3 to give the triacetate methyl ester of retinyl beta-glucuronide. Hydrolysis of this ester with sodium methylate in methanol gives retinyl beta-D-glucuronide in about 15% yield. The water-soluble retinyl beta-D-glucuronide was characterized by u.v.-visible, n.m.r. and mass spectra, by elemental analysis and by its susceptibility to hydrolysis by bacterial beta-glucuronidase. Retinyl beta-glucuronide, when administered intraperitoneally in saline (0.9% NaCl), supports well the growth of vitamin A-deficient rats. 相似文献
125.
Siti Mutripah Maria Dyah Nur Meinita Ji-Young Kang Gwi-Taek Jeong AB Susanto Romanus Edy Prabowo Yong-Ki Hong 《Journal of applied phycology》2014,26(1):687-693
Seaweeds, particularly species of red macroalgae, are promising resources for bioethanol production because of their exceptionally high carbohydrate content. Of 20 seaweeds evaluated, Palmaria palmata (Rhodymenia palmata) contained the highest carbohydrate content (469.8 mg g?1 seaweed) with a carrageenan content of 354 mg g?1 seaweed. Such a high carrageenan content makes the high-volume production of bioethanol feasible. Acid hydrolysis of P. palmata in 0.4 M H2SO4 at 125 °C for 25 min released 27 mg of glucose, 218.4 mg of reducing sugars, and 127.6 mg of galactose per gram of seaweed. Ethanol fermentation of these hydrolysis products using an inoculum concentration of 1.5 mg mL?1 at 30 °C and 72 h in a shaking incubator at 130 rpm yielded 17.3 mg of ethanol per gram of seaweed. 相似文献
126.
The capacities ofHalobacterium cutirubrum and a moderate halophile NRC 41227 to survive and recover from treatment with N-methyl-N-nitro-N-nitrosoguanidine have been compared.Halobacterium cutirubrum is resistant to this chemical and its mutation frequency is only slightly affected, whereas NRC 41227 is highly sensitive and its mutation frequency is markedly increased. The chemically treated extreme halophile fully regains viability during liquid holding, in notable contrast to its known failure to recover from the effects of ultraviolet irradiation. 相似文献
127.
Most cell surface receptors for growth factors and cytokines dimerize in order to mediate signal transduction. For many such receptors, the Janus kinase (Jak) family of non-receptor protein tyrosine kinases are recruited in pairs and juxtaposed by dimerized receptor complexes in order to activate one another by trans-phosphorylation. An alternative mechanism for Jak trans-phosphorylation has been proposed in which the phosphorylated kinase interacts with the Src homology 2 (SH2) domain of SH2-B, a unique adaptor protein with the capacity to homo-dimerize. Building on a rule-based kinetic modeling approach that considers the concerted nature and combinatorial complexity of modular protein domain interactions, we examine these mechanisms in detail, focusing on the growth hormone (GH) receptor/Jak2/SH2-Bβ system. The modeling results suggest that, whereas Jak2-(SH2-Bβ)2-Jak2 heterotetramers are scarcely expected to affect Jak2 phosphorylation, SH2-Bβ and dimerized receptors synergistically promote Jak2 trans-activation in the context of intracellular signaling. Analysis of the results revealed a unique mechanism whereby SH2-B and receptor dimers constitute a bipolar ‘clamp’ that stabilizes the active configuration of two Jak2 molecules in the same macro-complex. 相似文献
128.
Marije Oosting Kathrin Buffen Subbarao RK Malireddi Patrick Sturm Ineke Verschueren Marije I Koenders Frank L van de Veerdonk Jos WM van der Meer Mihai G Netea Thirumala-Devi Kanneganti Leo AB Joosten 《Arthritis research & therapy》2012,14(6):R247
Introduction
The protein platform called the NOD-like-receptor -family member (NLRP)-3 inflammasome needs to be activated to process intracellular caspase-1. Active caspase-1 is able to cleave pro-Interleukin (IL)-1β, resulting in bioactive IL-1β. IL-1β is a potent proinflammatory cytokine, and thought to play a key role in the pathogenesis of Lyme arthritis, a common manifestation of Borrelia burgdorferi infection. The precise pathways through which B. burgdorferi recognition leads to inflammasome activation and processing of IL-1β in Lyme arthritis has not been elucidated. In the present study, we investigated the contribution of several pattern recognition receptors and inflammasome components in a novel murine model of Lyme arthritis.Methods
Lyme arthritis was elicited by live B. burgdorferi, injected intra-articularly in knee joints of mice. To identify the relevant pathway components, the model was applied to wild-type, NLRP3-/-, ASC-/-, caspase-1-/-, NOD1-/-, NOD2-/-, and RICK-/- mice. As a control, TLR2-/-, Myd88-/- and IL-1R-/- mice were used. Peritoneal macrophages and bone marrow-derived macrophages were used for in vitro cytokine production and inflammasome activation studies. Joint inflammation was analyzed in synovial specimens and whole knee joints. Mann-Whitney U tests were used to detect statistical differences.Results
We demonstrate that ASC/caspase-1-driven IL-1β is crucial for induction of B. burgdorferi-induced murine Lyme arthritis. In addition, we show that B. burgdorferi-induced murine Lyme arthritis is less dependent on NOD1/NOD2/RICK pathways while the TLR2-MyD88 pathway is crucial.Conclusions
Murine Lyme arthritis is strongly dependent on IL-1 production, and B. burgdorferi induces inflammasome-mediated caspase-1 activation. Next to that, murine Lyme arthritis is ASC- and caspase-1-dependent, but NLRP3, NOD1, NOD2, and RICK independent. Also, caspase-1 activation by B. burgdorferi is dependent on TLR2 and MyD88. Based on present results indicating that IL-1 is one of the major mediators in Lyme arthritis, there is a rationale to propose that neutralizing IL-1 activity may also have beneficial effects in chronic Lyme arthritis. 相似文献129.
K. N. Faber S. Westra H. R. Waterham I. Keizer-Gunnink W. Harder G. AB M. Veenhuis 《Applied microbiology and biotechnology》1996,45(1-2):72-79
We describe the synthesis and purification of two functional peptides, namely human insulin-like growth factor II (IGF-II)
and Xenopus laevis magainin II in Hansenula polymorpha after their synthesis as hybrid proteins fused to the C terminus of endogenous amine oxidase. The hybrid genes, placed under
control of the H. polymorpha alcohol oxidase promoter (PAOX), were integrated into the genomic alcohol oxidase locus, yielding stable production strains. High-level synthesis of the
fusion proteins, exceeding 20% of total cellular protein, was obtained when the transformed strains were grown in methanol-limited
chemostat cultures; when expressed by itself, i.e. in the absence of the amine oxidase gene, IGF-II could not be recovered
from crude cell extracts, probably as a result of rapid proteolytic degradation. Accumulation in peroxisomes did not significantly
affect the IGF-II protein stability when expressed in the absence of the carrier protein. Apparently, fusion to the large
(±78 kDa) amine oxidase carrier particularly stabilizes the peptides and prevents them from proteolysis. After partial purification,
the fusion partners were readily separated by factor Xa treatment.
Received: 16 June 1995 / Accepted: 20 September 1995 相似文献
130.
A new repetitive element of the CR1 family downstream of the chicken vitellogenin gene. 总被引:3,自引:2,他引:3
We have analyzed a repetitive DNA sequence found in the 3'-flanking region of the chicken vitellogenin gene. By its sequence, the repetitive DNA has been identified as a hitherto unreported member of the chicken CR1 family of repetitive elements. The CR1 sequence displays the structural characteristics of a long terminal repeat located at the 3' end of an avian retrovirus. The CR1 element lies 2.2 kb downstream of the vitellogenin gene and 'points' away from the gene rather than toward it. In this respect, this element differs from other CR1 repeats. The CR1 element is embedded in a region showing changes in chromatin structure implying a potential role for this sequence in determining the structural state of the local chromatin. 相似文献