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Sonal Josan Jae Mo Park Ralph Hurd Yi‐Fen Yen Adolf Pfefferbaum Daniel Spielman Dirk Mayer 《NMR in biomedicine》2013,26(12):1680-1687
Hyperpolarized 13C MRS allows the in vivo assessment of pyruvate dehydrogenase complex (PDC) flux, which converts pyruvate to acetyl‐coenzyme A (acetyl‐CoA). [1‐13C]pyruvate has been used to measure changes in cardiac PDC flux, with demonstrated increase in 13C‐bicarbonate production after dichloroacetate (DCA) administration. With [1‐13C]pyruvate, the 13C label is released as 13CO2/13C‐bicarbonate, and, hence, does not allow us to follow the fate of acetyl‐CoA. Pyruvate labeled in the C2 position has been used to track the 13C label into the TCA (tricarboxylic acid) cycle and measure [5‐13C]glutamate as well as study changes in [1‐13C]acetylcarnitine with DCA and dobutamine. This work investigates changes in the metabolic fate of acetyl‐CoA in response to metabolic interventions of DCA‐induced increased PDC flux in the fed and fasted state, and increased cardiac workload with dobutamine in vivo in rat heart at two different pyruvate doses. DCA led to a modest increase in the 13C labeling of [5‐13C]glutamate, and a considerable increase in [1‐13C]acetylcarnitine and [1,3‐13C]acetoacetate peaks. Dobutamine resulted in an increased labeling of [2‐13C]lactate, [2‐13C]alanine and [5‐13C]glutamate. The change in glutamate with dobutamine was observed using a high pyruvate dose but not with a low dose. The relative changes in the different metabolic products provide information about the relationship between PDC‐mediated oxidation of pyruvate and its subsequent incorporation into the TCA cycle compared with other metabolic pathways. Using a high dose of pyruvate may provide an improved ability to observe changes in glutamate. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Chun A. Changou Her-Shyong Shiah Li-Tzong Chen Servina Liu Frank Luh Shwu-Huey Liu Yung-Chi Cheng Yun Yen 《The oncologist》2021,26(3):e367-e373
Lessons Learned
- A PHY906 and capecitabine combination could be effective as a salvage therapy for patients with hepatocellular carcinoma (HCC) previously treated with multiple systemic therapies.
- This traditional Chinese medicine formulation can work with Western cancer chemotherapeutic agents to improve clinical outcomes or alleviate side effects for patients with advanced HCC.
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Eu Chin Ho HanYu Zhang Warren Ming Wu Ong KeXin Li Yen Tze Eileen Bei Satya Vijay Reddy Medapati 《International journal of audiology》2018,57(4):291-301
Objective: To examine the epidemiological and audiological profile, pattern of hearing aid (HA) fitting and usage among HA users in Singapore. Design: Retrospective cross-sectional study. Study sample: Cohort of 1068 subjects issued with HAs at a tertiary hospital between 2001 and 2013. Results: Mean age was 70?years with 50.8% male. Mean hearing loss (HL) was 63.1?dB and 69.5% had at least moderate-severe HL. Sensorineural HL was present in 66.4% and 69.8% had symmetrical HL. “Behind-the-Ear” HAs were cheaper than “In-Ear” HAs. Standard “Behind-The-Ear” HAs were also cheaper than “Receiver-in-Canal” HAs. Among In-Ear HAs, “In-the-Canal” and “Completely-in-Canal” were more popular than “In-the-Ear” HAs despite costing more. HA was used ≥4?days/week by 85.6% but >7?h per day by only 35.7%. Only 18% received bilateral first HA fitting. In multivariate analysis, younger age and symmetrical HL were predictors of bilateral HA uptake while better Pure-Tone-Audiometry of aided ear and >7?h of daily HA usage were predictors of successive HA fitting. Conclusions: HA users in Singapore were elderly and presented with advanced HL. Bilateral HA adoption and average daily use were low compared to other developed countries. Future research on understanding the suboptimal HA usage should explore patients' motivation, hearing disability, and HA effectiveness. 相似文献
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CIP2A is a poor prognostic factor and can be a diagnostic marker in papillary thyroid carcinoma
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Ting‐Ting Chao Hung‐Chune Maa Cheng‐Yi Wang Dee Pei Yao‐Jen Liang Yi‐Feng Yang Shuo‐Jiun Chou Yen‐Lin Chen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(12):1031-1037
Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma. CIP2A has recently been described as a prognostic marker in many cancers. In this study, we assessed the value of this novel prognostic marker in PTC. A total of 178 surgical specimens of both benign and malignant thyroid tumors were collected. Immunohistochemical staining for CIP2A, HBME‐1, galectin‐3, and CK19 was performed. Western blotting for CIP2A was also performed. CIP2A was expressed in 85.3% of malignant tumors and 12.1% of benign tumors. ROC analysis showed that the AUC for CIP2A was higher than those for other tumor markers. Western blotting showed that CIP2A expression was higher in PTC than in other tumors. Poor progression‐free survival was observed in the high‐CIP2A expression group. High CIP2A expression is a poor prognostic factor and can be a diagnostic marker in PTC. The presence of any two of the three indicated makers (CIP2A, galectin‐3, and HBME‐1) is strongly correlated with the diagnosis of PTC. 相似文献
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Chia-Ying Lee Huei-ling Yen Pei-wen Yeh Wan-Hsuan Lin Ying-Ying Cheng Yu-Lin Tzeng Hsin-Chi Wu 《Neuropsychologia》2012,50(14):3228-3239
The present study investigates how age, phonological saliency, and deviance size affect the presence of mismatch negativity (MMN) and positive mismatch response (P-MMR). This work measured the auditory mismatch responses to Mandarin lexical tones, initial consonants, and vowels in 4- to 6-year-old preschoolers using the multiple-deviant oddball paradigm. The data showed the coexistence of MMN and P-MMR in the same age group when responding to the three types of syllabic features in Mandarin. The transition from a predominantly positive response to a predominantly negative response supported the multiple MMN mechanisms. Congruent with the phonological saliency hypothesis and the phonetic acquisition order of Mandarin in behavioral studies, for the compulsory elements of Mandarin syllables, lexical tones, and vowels, the larger deviants elicited adult-like MMNs, whereas the smaller deviants elicited P-MMRs. The optional elements of the Mandarin syllables, the initial consonant, only elicited P-MMR in preschoolers. These findings suggest that MMN and P-MMR index different functional characteristics and may provide information on when and how children's speech perception becomes automatic at different developmental stages. 相似文献
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Hong‐Hwa Chen Christopher G. Wallace Yen‐Ta Chen Chih‐Chao Yang Steve Leu Yi‐Ching Chen Cheuk‐Kwan Sun Tzu‐Hsien Tsai Yung‐Lung Chen Sheng‐Ying Chung Hon‐Kan Yip 《Journal of pineal research》2014,57(1):16-32
This study tested whether combined therapy with melatonin and apoptotic adipose‐derived mesenchymal stem cells (A‐ADMSCs) offered additional benefit in ameliorating sepsis‐induced acute kidney injury. Adult male Sprague–Dawley rats (n = 65) were randomized equally into five groups: Sham controls (SC), sepsis induced by cecal‐ligation and puncture (CLP), CLP‐melatonin, CLP‐A‐ADMSC, and CLP‐melatonin‐A‐ADMSC. Circulating TNF‐α level at post‐CLP 6 hr was highest in CLP and lowest in SC groups, higher in CLP‐melatonin than in CLP‐A‐ADMSC and CLP‐melatonin‐A‐ADMSC groups (all P < 0.001). Immune reactivity as reflected in the number of splenic helper‐, cytoxic‐, and regulatory‐T cells at post‐CLP 72 hr exhibited the same pattern as that of circulating TNF‐α among all groups (P < 0.001). The histological scoring of kidney injury and the number of F4/80+ and CD14+ cells in kidney were highest in CLP and lowest in SC groups, higher in CLP‐melatonin than in CLP‐A‐ADMSC and CLP‐melatonin‐A‐ADMSC groups, and higher in CLP‐A‐ADMSC than in CLP‐melatonin‐A‐ADMSC groups (all P < 0.001). Changes in protein expressions of inflammatory (RANTES, TNF‐1α, NF‐κB, MMP‐9, MIP‐1, IL‐1β), apoptotic (cleaved caspase 3 and PARP, mitochondrial Bax), fibrotic (Smad3, TGF‐β) markers, reactive‐oxygen‐species (NOX‐1, NOX‐2), and oxidative stress displayed a pattern identical to that of kidney injury score among the five groups (all P < 0.001). Expressions of antioxidants (GR+, GPx+, HO‐1, NQO‐1+) were lowest in SC group and highest in CLP‐melatonin‐A‐ADMSC group, lower in CLP than in CLP‐melatonin and CLP‐A‐ADMSC groups, and lower in CLP‐melatonin‐ than in CLP‐A‐ADMSC‐tretaed animals (all P < 0.001). In conclusion, combined treatment with melatonin and A‐ADMSC was superior to A‐ADMSC alone in protecting the kidneys from sepsis‐induced injury. 相似文献
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