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991.
Yi-sheng Chen Hui-chung Wu Shwu-fen Pan Bo-guang Lin Yen-hung Lin Wen-cheng Tung Yueh-lin Li Chih-ming Chiang Fujitoshi Yanagida 《Annals of microbiology》2013,63(2):607-614
Two hundred cultures of lactic acid bacteria were isolated from eight yan-taozih (pickled peaches) samples, and four cultures were isolated from the main component of these samples, fresh peaches. Phenotypic and biochemical characteristics identified eight different bacterial groups (A–H) and showed that the majority of the isolates was heterofermentative lactic acid bacteria. The most common bacterial species in yan-taozih was Leuconostoc mesenteroides, although regional diversity was also observed among the lactic acid bacteria strains isolated. The antibacterial activities of the isolates were also determined, and 20 isolates were found to show inhibitory activity against the indicator strain Lactobacillus sakei JCM 1157T. The results of the sensory evaluation suggested that the diversity of lactic acid bacteria has a great effect on the aroma and formation of taste in the food product. Our findings suggest that Leuconostoc mesenteroides is the most abundant lactic acid bacteria in yan-taozih (pickled peaches) and that lactic acid bacteria strains play an important role in affecting the aroma and taste of the food product. 相似文献
992.
Michael G. Harrington Jiarong Chiang Janice M. Pogoda Megan Gomez Kris Thomas Sarah DeBoard Marion Karen J. Miller Prabha Siddarth Xinyao Yi Feimeng Zhou Sherri Lee Xianghong Arakaki Robert P. Cowan Thao Tran Cherise Charleswell Brian D. Ross Alfred N. Fonteh 《PloS one》2013,8(11)
Background
Early treatment of Alzheimer’s disease may reduce its devastating effects. By focusing research on asymptomatic individuals with Alzheimer’s disease pathology (the preclinical stage), earlier indicators of disease may be discovered. Decreasing cerebrospinal fluid beta-amyloid42 is the first indicator of preclinical disorder, but it is not known which pathology causes the first clinical effects. Our hypothesis is that neuropsychological changes within the normal range will help to predict preclinical disease and locate early pathology.Methods and Findings
We recruited adults with probable Alzheimer’s disease or asymptomatic cognitively healthy adults, classified after medical and neuropsychological examination. By logistic regression, we derived a cutoff for the cerebrospinal fluid beta amyloid42/tau ratios that correctly classified 85% of those with Alzheimer’s disease. We separated the asymptomatic group into those with (n = 34; preclinical Alzheimer’s disease) and without (n = 36; controls) abnormal beta amyloid42/tau ratios; these subgroups had similar distributions of age, gender, education, medications, apolipoprotein-ε genotype, vascular risk factors, and magnetic resonance imaging features of small vessel disease. Multivariable analysis of neuropsychological data revealed that only Stroop Interference (response inhibition) independently predicted preclinical pathology (OR = 0.13, 95% CI = 0.04–0.42). Lack of longitudinal and post-mortem data, older age, and small population size are limitations of this study.Conclusions
Our data suggest that clinical effects from early amyloid pathophysiology precede those from hippocampal intraneuronal neurofibrillary pathology. Altered cerebrospinal fluid beta amyloid42 with decreased executive performance before memory impairment matches the deposits of extracellular amyloid that appear in the basal isocortex first, and only later involve the hippocampus. We propose that Stroop Interference may be an additional important screen for early pathology and useful to monitor treatment of preclinical Alzheimer’s disease; measures of executive and memory functions in a longitudinal design will be necessary to more fully evaluate this approach. 相似文献993.
Tze‐Hsiang Chien Ya‐Ling Chiang Chin‐Pei Chen Petra Henklein Karen Hänel Ing‐Shouh Hwang Dieter Willbold Wolfgang B. Fischer 《Biopolymers》2013,99(9):628-635
Protein 3a is a 274 amino acid polytopic channel protein with three putative transmembrane domains (TMDs) encoded by severe acute respiratory syndrome corona virus (SARS‐CoV). Synthetic peptides corresponding to each of its three individual transmembrane domains (TMDs) are reconstituted into artificial lipid bilayers. Only TMD2 and TMD3 induce channel activity. Reconstitution of the peptides as TMD1 + TMD3 as well as TMD2 + TMD3 in a 1 : 1 mixture induces membrane activity for both mixtures. In a 1 : 1 : 1 mixture, channel like behavior is almost restored. Expression of full length 3a and reconstitution into artificial lipid bilayers reveal a weak cation selective (PK ≈ 2 PCl) rectifying channel. In the presence of nonphysiological concentration of Ca‐ions the channel develops channel activity. © 2013 Wiley Periodicals, Inc. Biopolymers 99:628–635, 2013. 相似文献
994.
Fu-Chia Yang Ya-Huei Lin Wei-Hao Chen Jing-Yi Huang Hsin-Yun Chang Su-Hui Su Hsiao-Ting Wang Chun-Yi Chiang Pang-Hung Hsu Ming-Daw Tsai Bertrand Chin-Ming Tan Sheng-Chung Lee 《The Journal of biological chemistry》2013,288(47):33861-33872
Salt-inducible kinase 2 (SIK2) is an important regulator of cAMP response element-binding protein-mediated gene expression in various cell types and is the only AMP-activated protein kinase family member known to interact with the p97/valosin-containing protein (VCP) ATPase. Previously, we have demonstrated that SIK2 can regulate autophagy when proteasomal function is compromised. Here we report that physical and functional interactions between SIK2 and p97/VCP underlie the regulation of endoplasmic reticulum (ER)-associated protein degradation (ERAD). SIK2 co-localizes with p97/VCP in the ER membrane and stimulates its ATPase activity through direct phosphorylation. Although the expression of wild-type recombinant SIK2 accelerated the degradation and removal of ERAD substrates, the kinase-deficient variant conversely had no effect. Furthermore, down-regulation of endogenous SIK2 or mutation of the SIK2 target site on p97/VCP led to impaired degradation of ERAD substrates and disruption of ER homeostasis. Collectively, these findings highlight a mechanism by which the interplay between SIK2 and p97/VCP contributes to the regulation of ERAD in mammalian cells. 相似文献
995.
Regulation of phenylalanine ammonia-lyase (PAL) gene family in wood forming tissue of Populus trichocarpa 总被引:1,自引:0,他引:1
996.
Naresh Kumar Pavel S. Cherkas Vidya Varathan Makiko Miyamoto Chen Yu Chiang Jonathan O. Dostrovsky Barry J. Sessle Terence J. Coderre 《Neurochemistry international》2013
Pregabalin is effective in treating many neuropathic pain conditions. However, the mechanisms of its analgesic effects remain poorly understood. The aim of the present study was to determine whether pregabalin suppresses facial mechanical hypersensitivity and evoked glutamate release in the medullary dorsal horn (MDH) in a rodent model of trigeminal neuropathic pain. Nociceptive mechanical sensitivity was assessed pre-operatively, and then post-operatively 1 h following pregabalin or vehicle (saline) treatment on post-operative days 2 and 5 following infraorbital nerve transection (IONX). In addition, an in vivo microdialysis probe was inserted into the exposed medulla post-operatively and dialysate samples were collected. Glutamate release was then evoked by mustard oil (MO) application to the tooth pulp, and the effects of pregabalin or vehicle were examined on the MDH glutamate release. Glutamate concentrations in the dialysated samples were determined by HPLC, and data analyzed by ANOVA. IONX animals (but not control animals) showed facial mechanical hypersensitivity for several days post-operatively. In addition, tooth pulp stimulation with MO evoked a transient release of glutamate in the MDH of IONX animals. Compared to vehicle, administration of pregabalin significantly attenuated the facial mechanical hypersensitivity as well as the MO-evoked glutamate release in MDH. This study provides evidence in support of recent findings pointing to the usefulness of pregabalin in the treatment of orofacial neuropathic pain. 相似文献
997.
998.
Hung‐Yun Lin Dominique Delmas Ole Vang Tze‐Chen Hsieh Sharon Lin Guei‐Yun Cheng Hsiao‐Ling Chiang Chiao En Chen Heng‐Yuan Tang Dana R. Crawford Jacqueline Whang‐Peng Jaulang Hwang Leroy F. Liu Joseph M. Wu 《Journal of cellular biochemistry》2013,114(8):1940-1954
Ceramide is a member of the sphingolipid family of bioactive molecules demonstrated to have profound, diverse biological activities. Ceramide is a potential chemotherapeutic agent via the induction of apoptosis. Exposure to ceramide activates extracellular‐signal‐regulated kinases (ERK)1/2‐ and p38 kinase‐dependent apoptosis in human ovarian cancer OVCAR‐3 cells, concomitant with an increase in the expression of COX‐2 and p53 phosphorylation. Blockade of cyclooxygenase‐2 (COX‐2) activity by siRNA or NS398 correspondingly inhibited ceramide‐induced p53 Ser‐15 phosphorylation and apoptosis; thus COX‐2 appears at the apex of the p38 kinase‐mediated signaling cascade induced by ceramide. Induction of apoptosis by ceramide or resveratrol was inhibited by the endocytosis inhibitor, cytochalasin D (CytD); however, cells exposed to resveratrol showed greater sensitivity than ceramide‐treated cells. Ceramide‐treated cells underwent a dose‐dependent reduction in trans‐membrane potential. Although both ceramide and resveratrol induced the expressions of caspase‐3 and ‐7, the effect of inducible COX‐2 was different in caspase‐7 expression induced by ceramide compared to resveratrol. In summary, resveratrol and ceramide converge on an endocytosis‐requiring, ERK1/2‐dependent signal transduction pathway and induction of COX‐expression as an essential molecular antecedent for subsequent p53‐dependent apoptosis. In addition, expressions of caspase‐3 and ‐7 are observed. However, a p38 kinase‐dependent signal transduction pathway and change in mitochondrial potential are also involved in ceramide‐induced apoptosis. J. Cell. Biochem. 114: 1940–1954, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
999.
Large numbers of protoplasts (106 to 3·2 × 107 per gram fresh weight) were routinely isolated from two Taiwanese species of Porphyra: P. dentata and P. crispata. Intermediate and final forms of regeneration were observed, including swollen cells, monospore-like cells, filaments, callus-like structures and bladelets. Regeneration of leafy plants was achieved from protoplasts of P. crispata, whereas only conchocelis-like filaments were regenerated from protoplasts of P. dentata. In this latter species, conchosporangia and monosporangia appeared on the filaments upon cultivation at 25 °C. The variability in regenerative patterns is discussed. 相似文献
1000.
Chung-Jen Wang Chien-Chih Chen Huey-Jen Tsay Feng-Yi Chiang Mine-Fong Wu Young-Ji Shiao 《Journal of biomedical science》2013,20(1):55