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991.
992.
Twenty new 5-(hydroxyalkyl)-2-cyclopentenone derivatives (hygrophorones) could be isolated from Hygrophorus latitabundus, H. olivaceoalbus, H. persoonii, and H. pustulatus. Their fungicidal activity was exemplarily tested. The hygrophorones have structural similarities to the antibiotic pentenomycin. Chemically, hygrophorones are 2-cyclopentenones with hydroxy or acetoxy substituents at C-4 and/or C-5. An odd-numbered 1' oxidized alkyl chain (C(11), C(13), C(15), or C(17)) is attached at C-5. In addition, from H. persoonii the new gamma-butyrolactone derivative [5-(E)-2-hydroxytetradexylidene-5H-furan-2-one] could be isolated. Some hygrophorones are responsible for the color reaction of the stipes of these fungi upon treatment with potassium hydroxide solution. Structural elucidations are based on 1D ((1)H, (13)C) and 2D (COSY, NOESY, HSQC, HMBC) NMR spectroscopic analyses as well as HR-FT-ICR-MS investigations. 相似文献
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995.
Integration and channeling of calcium signaling through the CBL calcium sensor/CIPK protein kinase network 总被引:23,自引:0,他引:23
Plant development and reproduction depend on a precise recognition of environmental conditions and the integration of this information with endogenous metabolic and developmental cues. Calcium ions have been firmly established as ubiquitous second messengers functioning in these processes. Calcium signal deciphering and signal-response coupling often involve calcium-binding proteins as responders or relays in this information flow. Here we review the calcineurin B-like protein (CBL) calcium sensor/CBL-interacting protein kinase (CIPK) network as a newly emerging signaling system mediating a complex array of environmental stimuli. We focus particularly on the mechanisms generating signaling specificity. Moreover, we emphasize the functional implications that are emerging from the analyses of CBL and CIPK loss-of-function mutants. 相似文献
996.
Song HM Fong KD Nacamuli RP Warren SM Fang TD Mathy JA Cowan CM Aalami OO Longaker MT 《Plastic and reconstructive surgery》2004,113(6):1685-1697
Using a physiologic model of mouse cranial suture fusion, the authors' laboratory has previously demonstrated that transforming growth factor (TGF)-betas appear to be more abundantly expressed in the suture complex of the fusing posterior frontal compared with the patent sagittal suture. Furthermore, the authors have shown that by blocking TGF-beta signaling with a replication-deficient adenovirus encoding a defective, dominant negative type II TGF-beta receptor (AdDN-TbetaRII), posterior frontal suture fusion was inhibited. In this study, the authors attempt to further elucidate the role of TGF-beta in cranial suture fusion by investigating possible mechanisms of AdDN-TbetaRII-mediated cranial suture patency using both an established organ culture model and a novel in vitro co-culture system that recapitulates the in vivo anatomic dura mater/cranial suture relationship. In this article, the authors demonstrate that blocking TGF-beta signaling with the AdDN-TbetaRII construct led to inhibition of cellular proliferation in the suture mesenchyme and subjacent dura mater during the early period of predicted posterior frontal suture fusion. Interestingly, co-culture experiments revealed that transfecting osteoblasts with AdDN-TbetaRII led to alterations in the gene expression levels of two important bone-related molecules (Msx2 and osteopontin). Inhibiting TGF-beta signaling prevented time-dependent suppression of Msx2 and prevented induction of osteopontin, thereby retarding osteoblast differentiation. Furthermore, the authors demonstrated that the AdDN-TbetaRII construct was capable of blocking TGF-beta -mediated up-regulation of collagen IalphaI, an extracellular matrix molecule important for bone formation. Collectively, these data strongly suggest that AdDN-TbetaRII maintains posterior frontal patency, in part by altering early events in de novo bone formation, including cellular proliferation and early extracellular matrix production. 相似文献
997.
Hölmich LR Vejborg IM Conrad C Sletting S Høier-Madsen M Fryzek JP McLaughlin JK Kjøller K Wiik A Friis S 《Plastic and reconstructive surgery》2004,114(1):204-14; discussion 215-6
Implant rupture is a well-known complication of breast implant surgery that can pass unnoticed by both patient and physician. To date, no prospective study has addressed the possible health implications of silicone breast implant rupture. The aim of the present study was to evaluate whether untreated ruptures are associated with changes over time in magnetic resonance imaging findings, serologic markers, or self-reported breast symptoms. A baseline magnetic resonance imaging examination was performed in 1999 on 271 women who were randomly chosen from a larger cohort of women having cosmetic breast implants for a median period of 12 years (range, 3 to 25 years). A follow-up magnetic resonance imaging examination was carried out in 2001, excluding women who underwent explantation in the period between the two magnetic resonance imaging examinations (n = 44). On the basis of these examinations, the authors identified 64 women who had at least one ruptured implant at the first magnetic resonance imaging examination and, for comparison, all women who had intact implants at both examinations (n = 98). Magnetic resonance images from the two examinations were compared and changes in rupture configuration were evaluated. Comparisons were also made for self-reported breast symptoms occurring during the study period and for changes in serum values of antinuclear antibodies, rheumatoid factor, and cardiolipin antibodies immunoglobulin G and immunoglobulin M. The majority of the women with implant rupture had no visible magnetic resonance imaging changes of their ruptured implants. For 11 implants (11 percent) in 10 women, the authors observed progression of silicone seepage, either as a conversion from intracapsular into extracapsular rupture (n = 7), as progression of extra-capsular silicone (n = 3), or as increasing herniation of the silicone within the fibrous capsule (n = 1); however, in most cases, these changes were minor. Some changes could be ascribed to trauma, but others seemed spontaneous. There was no increase in levels of autoantibodies during the study period in either study group. Women with untreated implant ruptures reported a significant increase in nonspecific breast changes (odds ratio, 2.1; 95 percent confidence interval, 1.2 to 3.8) compared with women without ruptures. On the basis of this first study of women with untreated silicone breast implant rupture, the authors conclude that implant rupture is a relatively harmless condition, which only rarely progresses and gives rise to notable symptoms. Even so, because of a small risk of silicone spread, the authors suggest that women with implant ruptures be followed clinically, if not operated on. Because implant ruptures often occur asymptomatically, any woman with silicone implants, regardless of rupture status, should be evaluated at regular intervals. 相似文献
998.
Boehm RA Muensterer OJ Till H 《Plastic and reconstructive surgery》2004,114(3):668-73; discussion 674-5
Surgical correction of pectus excavatum in children has gained new momentum since the introduction of the new minimally invasive repair by Nuss. To date, no studies directly evaluate the outcome of the new technique versus that of the conventional technique. From 2000 to 2002, 28 patients underwent pectus excavatum correction in the authors' hospital. Twenty-one were treated by minimally invasive repair of pectus excavatum and seven patients had open correction. Intraoperative and postoperative complications, clinical outcome, and patient satisfaction were evaluated. In the minimally invasive repair of pectus excavatum group, the children were younger (14.4 +/- 2.9 versus 17.8 +/- 3.2 years), had shorter operation times (53 +/- 18 versus 125 +/- 6 minutes), and had less blood loss (minimal versus 380 +/- 175 ml). No intraoperative complications were recorded. In the conventional group, two pleural lacerations occurred. Early postoperative complications in the minimally invasive repair group included two pneumothoraces and one case of pleural effusion. In the conventional group, one pneumothorax and one case of pleural effusion occurred. Late postoperative complications in the Nuss group included one costal erosion, two bar dislocations, one severe wound infection requiring bar removal, one hematothorax, and one case of postpericardiotomy syndrome; in the conventional group, there was one severe wound infection. In both groups, the patients rated their cosmetic results as good to very good. Minimally invasive repair of pectus excavatum is a novel method with clear advantages, such as limited surgical trauma and small scars. The high rate of postoperative complications may decrease with growing experience in the future. In well-selected patients (age, symmetric deformity), the Nuss procedure may become the method of choice. However, there is still a lack of long-term follow-up. 相似文献
999.
Comparative genomics identifies a flagellar and basal body proteome that includes the BBS5 human disease gene 总被引:31,自引:0,他引:31
Li JB Gerdes JM Haycraft CJ Fan Y Teslovich TM May-Simera H Li H Blacque OE Li L Leitch CC Lewis RA Green JS Parfrey PS Leroux MR Davidson WS Beales PL Guay-Woodford LM Yoder BK Stormo GD Katsanis N Dutcher SK 《Cell》2004,117(4):541-552
Cilia and flagella are microtubule-based structures nucleated by modified centrioles termed basal bodies. These biochemically complex organelles have more than 250 and 150 polypeptides, respectively. To identify the proteins involved in ciliary and basal body biogenesis and function, we undertook a comparative genomics approach that subtracted the nonflagellated proteome of Arabidopsis from the shared proteome of the ciliated/flagellated organisms Chlamydomonas and human. We identified 688 genes that are present exclusively in organisms with flagella and basal bodies and validated these data through a series of in silico, in vitro, and in vivo studies. We then applied this resource to the study of human ciliation disorders and have identified BBS5, a novel gene for Bardet-Biedl syndrome. We show that this novel protein localizes to basal bodies in mouse and C. elegans, is under the regulatory control of daf-19, and is necessary for the generation of both cilia and flagella. 相似文献
1000.