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161.
Aims
Syncope is defined as temporary loss of consciousness and postural tone resulting from an abrupt transient decrease in cerebral blood flow. The present work aimed at determining how diagnostic tests are used in the evaluation of pediatric syncope at a tertiary pediatric referral center and to report on the utility and the yield of these tests.Settings and Design
Retrospective study conducted at a tertiary referral arrhythmolology serviceMethods and Material
The clinical charts of 234 pediatric patients presenting with a primary complaint of syncope with an average age of 7.48 ± 3.82(3.5-16) years were reviewed by the investigators.Statistical analysis used
Statistical Package of social science (SPSS) version 9,0 was used for analysis of data.Results
The commonest trigger for syncope in the study population was early following exercise (n=65) and the commonest prodrome was palpitation, noted in 25 patients. A murmur was present in 19 of our patients (8.3%) while 10.7% (n=25) had abnormal ECGs. Of the 106 echocardiograms done, 14 (13.2%) were abnormal. Only two of them were missed by ECG. All patients were offered ambulatory 24 hour ECG. One patient with sick sinus syndrome was diagnosed only with Holter.Conclusions
Clues to the presence of cardiac syncope may include acute onset of syncope, frequent episodes, low difference between blood pressure readings in supine and erect positions (after standing for 2 minutes) and most importantly an abnormal 12 lead ECG. Transthoracic echo and Holter monitoring have low yield in pediatric syncope. 相似文献162.
163.
Torii K Nishizawa K Kawasaki A Yamashita Y Katada M Ito M Nishimoto I Terashita K Aiso S Matsuoka M 《Cellular signalling》2008,20(7):1256-1266
Wnts are secreted glycoproteins that control diverse biological processes, such as proliferation, differentiation, and apoptosis. We here found that Wnt5a inhibited apoptosis induced by serum deprivation in primary-cultured human dermal fibroblasts. Anti-apoptotic activity of Wnt5a was not inhibited by a dickkopf-1 (DKK), which blocks the canonical Wnt pathway. On the other hand, loss of function of protein kinase A (PKA), induced by treatment with PKA inhibitors, siRNA-mediated knocking down of endogenous PKA catalytic subunits, or enforced expression of dominant-negative PKA inhibited the Wnt5a anti-apoptotic activity, indicating the involvement of PKA in the Wnt5a anti-apoptotic activity. In agreement, phosphorylation levels of a cAMP response element binding protein (CREB), a representative downstream effector of PKA, the activation of which is known to lead to the pro-survival effects, was elevated by Wnt5a. In addition, Wnt5a increased the nuclear beta-catenin level and treatment with imatinib or ionomycin, either of which blocks the beta-catenin pathway, reduced the anti-apoptotic activity of Wnt5a, together suggesting the simultaneous involvement of the beta-catenin-mediated pathway in the Wnt5a anti-apoptotic activity. Based on another finding indicating that Wnt5a upregulated PKA-mediated phosphorylation of glycogen synthase kinase-3beta (GSK-3beta) at serine 9 that caused inactivation of GSK-3beta and subsequently resulted in activation of the beta-catenin pathway, we have speculated that the Wnt5a anti-apoptotic activity may be partially mediated by PKA-mediated phosphorylation of GSK-3beta and subsequent activation of the beta-catenin pathway. 相似文献
164.
165.
Shimonaga T Konishi M Oyama Y Fujiwara S Satoh A Fujita N Colleoni C Buléon A Putaux JL Ball SG Yokoyama A Hara Y Nakamura Y Tsuzuki M 《Plant & cell physiology》2008,49(1):103-116
Storage glucans were analyzed in the Porphyridiales which include the most primitive and phylogenetically diverged species in the Rhodophyta, to understand early evolution of the glucan structure in the Rhodophyta. The storage glucans of both Galdieria sulphuraria and Cyanidium caldarium consisted of glycogen, while those of Rhodosorus marinus, Porphyridium purpureum, P. sordidum and Rhodella violacea could be defined as semi-amylopectin. X-ray diffraction analysis of the glucans demonstrated variation in the crystalline structure: the patterns in P. purpureum and R. violacea were of A- and B-types, respectively, while alpha-glucans of R. marinus and P. sordidum displayed structures with lower crystallinity. Electron microscopic observations indicated that the alpha-glucans of P. sordidum consisted of two kinds of granules; a minor component of more dense granules with crystalline leaflets and a major component of softer ones without crystalline structure. Gel permeation chromatography showed that all the species containing the semi-amylopectin-type glucans also contained amylose, although the relative amounts of this fraction were different depending on the species. Our results are consistent with two distinct evolution scenarios defined either by the independent acquisition of semi-crystalline starch-like structures in the different plant lineages or more probably by the loss of starch and reversion to glycogen synthesis in cyanidian algae growing in hot and acid environments. 相似文献
166.
167.
Masatoshi Inden Yoshihisa Kitamura Aya Tamaki Takashi Yanagida Tomonori Shibaike Atsuko Yamamoto Kazuyuki Takata Hiroyuki Yasui Takahiro Taira Hiroyoshi Ariga Takashi Taniguchi 《Neurochemistry international》2009,55(8):760-767
Pramipexole, an agonist for dopamine (DA) D2/D3-receptors, has been used to treat both early and advanced Parkinson's disease (PD). In this study, we examined the effect of pramipexole on DA neurons in a PD model of C57BL/6 mice, which were treated with rotenone (30 mg/kg, p.o.) daily for 28 days. Pramipexole (1 mg/kg, i.p.) was injected daily 30 min before each oral administration of rotenone. Chronic oral administration of rotenone caused a loss of DA neurons in the substantia nigra pars compacta (SNpc), motor deficits and the up-regulation of α-synuclein immunoreactivity in some surviving DA neurons. Pramipexole inhibited rotenone-induced DA neuronal death and motor deficits, and reduced immunoreactivity for α-synuclein. In addition, pramipexole inhibited the in vitro oligomerization of human wild-type α-synuclein by H2O2 plus cytochrome c. To examine the neuroprotective effect of pramipexole against oxidative stress, we used a DJ-1-knockdown SH-SY5Y cell line and electron spin resonance (ESR) spectrometry. Simultaneous treatment with H2O2 and pramipexole resulted in the significant protection of DJ-1-knockdown cells against cell death in a concentration-dependent manner. A high concentration of pramipexole directly scavenged hydroxyl radical (OH) generated from H2O2 and Fe2+. Furthermore, pramipexole increased Bcl-2 immunoreactivity in DA neurons in the SNpc. These results suggest that pramipexole may protect DA neurons against exposure to rotenone by chronic oral administration, and this effect is mediated by multiple functions including scavenging of OH and induction of Bcl-2 protein. 相似文献
168.
The diving behavior of Adélie penguins Pygoscelis adeliae was investigated using time–depth recorders during the incubation period in the fast sea-ice area of Lützow-Holm Bay, Antarctica.
Dive profiles and activity/time allocation suggested that penguins were obligated to walk on the fast-ice for 90–100 km until
a polynya, which they used as an access to the pack-ice zone. Dive depth did not differ between males and females, though
males’ dive duration was longer than that of females. Dive depth was slightly shallower and dive duration was shorter during
the incubation than during the chick-rearing phase. Birds dove throughout the day, although less frequently around midnight,
and there was no clear diel change in dive depth. This daily dive pattern during incubation period was similar to that previously
observed during the chick-rearing period in a fast sea-ice area, but differed from that observed in sea-ice-free area. Variations
in diving behavior resulted from different environmental conditions, such as foraging area with different sea-ice condition,
as well as from different life history strategies. 相似文献
169.
Haruhiko Washida Aya Sugino Sachiyo Kaneko Naoko Crofts Chotipa Sakulsingharoj Dongwook Kim Sang-Bong Choi Shigeki Hamada Masahiro Ogawa Changlin Wang Asim Esen Thomas J.V. Higgins Thomas W. Okita 《The Plant journal : for cell and molecular biology》2009,60(1):146-155
The RNAs for the storage proteins of rice ( Oryza sativa ), prolamines and glutelins, which are stored as inclusions in the lumen of the endoplasmic reticulum (ER) and storage vacuoles, respectively, are targeted by specific cis -localization elements to distinct subdomains of the cortical ER. Glutelin RNA has one or more cis -localization elements (zip codes) at the 3' end of the RNA, whereas prolamine has two cis -elements; one located in the 5' end of the coding sequence and a second residing in the 3'-untranslated region (UTR). We had earlier demonstrated that the RNAs for the maize zeins ('prolamine' class) are localized to the spherical protein body ER (PB-ER) in developing maize endosperm. As the PB-ER localization of the 10-kDa δ-zein RNA is maintained in developing rice seeds, we determined the number and proximate location of their cis -localization elements by expressing GFP fusions containing various zein RNA sequences in transgenic rice and analyzing their spatial distribution on the cortical ER by in situ RT-PCR and confocal microscopy. Four putative cis -localization elements were identified; three in the coding sequences and one in the 3'-UTR. Two of these zip codes are required for restricted localization to the PB-ER. Using RNA targeting determinants we show, by mis-targeting the storage protein RNAs from their normal destination on the cortical ER, that the coded proteins are redirected from their normal site of deposition. Targeting of RNA to distinct cortical ER subdomains may be the underlying basis for the variable use of the ER lumen or storage vacuole as the final storage deposition site of storage proteins among flowering plant species. 相似文献
170.
Hiroshi Abe Takeshi Shimoda Jun Ohnishi Soichi Kugimiya Mari Narusaka Shigemi Seo Yoshihiro Narusaka Shinya Tsuda Masatomo Kobayashi 《BMC plant biology》2009,9(1):97