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91.
Chih-Hua Tseng Chang-Sheng Lin Pin-Keng Shih Lo-Ti Tsao Jih-Pyang Wang Chih-Mei Cheng Cherng-Chyi Tzeng Yeh-Long Chen 《Bioorganic & medicinal chemistry》2009,17(18):6773-6779
Synthesis and anti-inflammatory effects of certain furo[3′,2′:3,4]naphtho[1,2-d]imidazole derivatives 12–18 were studied. These compounds were synthesized from naphtho[1,2-b]furan-4,5-dione (10) which in turn was prepared from the known 2-hydoxy-1,4-naphthoquinone (7) in a one pot reaction. Furo[3′,2′:3,4]naphtho[1,2-d]imidazole (12) was inactive (IC50 value of >30 μM) while its 5-phenyl derivative 13, with an IC50 value of 16.3 and 11.4 μM against lysozyme and β-glucuronidase release, respectively, was comparable to the positive trifluoperazine. The same potency was observed for 5-furan derivative 16 with an IC50 value of 19.5 and 11.3 μM against lysozyme and β-glucuronidase release, respectively. An electron-withdrawing NO2 substituted on 5-phenyl or 5-furanyl group led to the devoid of activity as in the cases of 14 and 17. Among them, compound 15 exhibited significant inhibitory effects, with an IC50 value of 7.4 and 5.0 μM against lysozyme and β-glucuronidase release, respectively.For the LPS-induced NO production, the phenyl derivatives 12–15 were inactive while the nitrofuran counterparts 17 and 18 suppress LPS-induced NO production significantly, with an IC50 value of 1.5 and 1.3 μM, respectively, which are more active than that of the positive 1400 W. Compounds 16–18 were capable of inhibiting LPS-induced iNOS protein expression at a dose-dependent manner in which compound 18, with an IC50 of 0.52 μM in the inhibition of iNOS expression, is approximately fivefold more potent than that of the positive 1400 W. In the CLP rat animal model, compound 18 was found to be more active than the positive hydrocortisone in the inhibition of the iNOS mRNA expression in rat lung tissue. The sepsis-induced PGE2 production in rat serum decreased 150% by the pretreatment of 18 in a dose of 10 mg/kg. 相似文献
92.
The ultrastructure of the pineal organ was studied in the tropical megachiropteran Rousettus leschenaulti. The pineal lies deep beneath the hemispheres adjacent to the third ventricle and is traversed by the habenular commissure anteriorly. Its parenchyma consists of a uniform population of light and occasional dark pinealocytes which appear to differ only in the degree of cytoplasmic staining. Pinealocytes are characterized by well developed Golgi bodies associated with numerous small vesicles, many mitochondria and polyribosomes, and frequent subsurface cisternae. Lipid droplets and elements of smooth endoplasmic reticulum are scant. Cisternae of granular endoplasmic reticulum are occasionally dilated. A distinct feature is the abundance of clear vesicles in the pinealocyte pericapillary terminals, which also frequently contain granular vesicles and a very large vacuole. The pineal is further characterized by the presence of a small number of glial cells and myelinated nerve fibers. A broad perivascular space investing numerous capillaries contains glial-cell and pinealocyte processes, collagen fibrils and abundant unmyelinated nerve fibers. Tortuous extensions of the perivascular space enter the pineal parenchyma where they come in close proximity to branched intercellular channels or canaliculi characterized by specialized junctions and microvilli. Differences between the pineal of the non-hibernating megachiropteran Rousettus and that of the hibernating microchiropteran bats, and structural similarities to the pineal of tropical rodents are discussed. 相似文献
93.
Wen-Long Hu Chih-Hao Chang Yu-Chiang Hung Ying-Jung Tseng I-Ling Hung Sheng-Feng Hsu 《PloS one》2014,9(10)
Objective
To investigate the clinical effects of laser acupuncture therapy for temporomandibular disorders (TMD) after ineffective previous treatments.Methods
A retrospective observational study was conducted in 29 treatment-resistant TMD patients (25 women, 4 men; age range, 17–67 years). Subjects were treated 3 times per week for 4 weeks with the Handylaser Trion (GaAlAs laser diode, 810 nm, 150 mW, pulsed waves), which delivered 0.375 J of energy (5 s) to ST7, ST6, and LI4 and 3 J (40 s) to each Ashi point, 7.5–26.25 J/cm2 in total. The visual analog scale (VAS) and maximal mouth opening (MMO) were evaluated before and after treatment.Results
VAS analysis showed that the patients were free of pain at rest (endpoint) after 5.90±6.08 sessions of laser acupuncture for acute TMD and after 16.21±17.98 sessions for chronic TMD. The VAS score on palpation of the temporomandibular joint reduced to 0.30±0.67 for patients with acute TMD (p = 0.005) and to 0.47±0.84 for those with chronic TMD (p<0.001). The MMO significantly increased in patients with acute TMD (7.80±5.43 mm, p = 0.008) and in patients with chronic TMD (15.58±7.87 mm, p<0.001).Conclusions
Our study shows that laser acupuncture therapy improves the symptoms of treatment-resistant TMD. Further studies with a more appropriate design, involving long-term follow-up examinations in a larger patient sample, are needed to evaluate its efficacy. 相似文献94.
Niche regulation of corneal epithelial stem cells at the limbus 总被引:19,自引:0,他引:19
Among all adult somatic stem cells,those of the corneal epithelium are unique in their exclusive location in a definedlimbai structure termed Palisades of Vogt.As a result,surgical engraftment oflimbal epithelial stem cells with or withoutex vivo expansion has long been practiced to restore sights in patients inflicted with limbal stem cell deficiency.Neverthe-less,compared to other stem cell examples,relatively little is known about the limbal niche,which is believed to play apivotal role in regulating self-renewal and fate decision of limbal epithelial stem cells.This review summarizes relevantliterature and formulates several key questions to guide future research into better understanding of the pathogenesis oflimbal stem cell deficiency and further improvement of the tissue engineering of the corneal epithelium by focusing onthe limbal niche. 相似文献
95.
Deng-Yu Tseng Pei-Lin Ho Sung-Yan Huang Sheng-Chi Cheng Ya-Li Shiu Chiu-Shia Chiu Chun-Hung Liu 《Fish & shellfish immunology》2009,26(2):339-344
Effects of Bacillus subtilis E20 isolated from fermented soybean on immune parameters and the disease resistance of the white shrimp (Litopenaeus vannamei) after 98 days of B. subtilis E20 feeding were evaluated in this study. Shrimp fed B. subtilis E20-containing diets at concentrations of 106 (E206), 107 (E207), and 108 (E208) cfu kg?1, respectively, had significantly increased survival rates of 13.3%, 16.7%, and 20%, compared to the control (fed no probiotic) after being challenged with Vibrio alginolyticus. There were no significant differences in the total hemocyte count, respiratory burst, or superoxide dismutase glutathione peroxidase among all treatments. Shrimp fed a higher concentration of the probiotic (E208) exhibited significant increases in phenoloxidase activity, phagocytic activity, and clearance efficiency compared to control shrimp. In addition, B. subtilis E20 showed a weaker inhibitory effect against the growth of Aeromona hydrophila with around a 0.3-cm inhibitory zone, but showed no inhibitory effects against other selected pathogens, such as white shrimp pathogens: V. alginolyticus and Vibrio vulnificus. These results suggest that the increased resistance of shrimp after B. subtilis E20 consumption occurs through immune modifications, such as increases in phenoloxidase activity, phagocytic activity, and clearance efficiency against V. alginolyticus. 相似文献
96.
97.
Sin-Fen Hu Yu-Hsin Huang Chan-Pin Lin Li-Yu Daisy Liu Syuan-Fei Hong Chiao-Yin Yang Hsiao-Feng Lo Ting-Yu Tseng Wei-Yao Chen Shih-Shun Lin 《PloS one》2015,10(6)
PHYL1 and SAP54 are orthologs of pathogenic effectors of Aster yellow witches’-broom (AYWB) phytoplasma and Peanut witches’-broom (PnWB) phytoplasma, respectively. These effectors cause virescence and phyllody symptoms (hereafter leafy flower) in phytoplasma-infected plants. T0 lines of transgenic Arabidopsis expressing the PHYL1 or SAP54 genes (PHYL1 or SAP54 plants) show a leafy flower phenotype and result in seedless, suggesting that PHYL1 and SAP54 interfere with reproduction stage that restrict gain-of-function studies in the next generation of transgenic plants. Turnip mosaic virus (TuMV) mild strain (TuGK) has an Arg182Lys mutation in the helper-component proteinase (HC-ProR182K) that blocks suppression of the miRNA pathway and prevents symptom development in TuGK-infected plants. We exploited TuGK as a viral vector for gain-of-function studies of PHYL1 and SAP54 in Arabidopsis plants. TuGK-PHYL1- and TuGK-SAP54-infected Arabidopsis plants produced identical leafy flower phenotypes and similar gene expression profiles as PHYL1 and SAP54 plants. In addition, the leafy flower formation rate was enhanced in TuGK-PHYL1- or TuGK-SAP54-infected Arabidopsis plants that compared with the T0 lines of PHYL1 plants. These results provide more evidence and novel directions for further studying the mechanism of PHYL1/SAP54-mediated leafy flower development. In addition, the TuGK vector is a good alternative in transgenic plant approaches for rapid gene expression in gain-of-function studies. 相似文献
98.
Fen-Yu Tseng Wen-Yuan Lin Chia-Ing Li Tsai-Chung Li Cheng-Chieh Lin Kuo-Chin Huang 《PloS one》2015,10(4)
Background
The association between subclinical hypothyroidism (SCH) and cancer mortality is seldom discussed.Methods
A total of 115,746 participants without thyroid disease history, aged 20 and above, were recruited from four nationwide health screening centers in Taiwan from 1998 to 1999. SCH was defined as a serum thyroid-stimulating hormone (TSH) level of 5.0–19.96 mIU/L with normal total thyroxine concentrations. Euthyroidism was defined as a serum TSH level of 0.47–4.9 mIU/L. Cox proportional hazards regression analyses were used to estimate the relative risks (RRs) of death from cancer for adults with SCH during a 10-year follow-up period.Results
Among 115,746 adults, 1,841 had SCH (1.6%) and 113,905 (98.4%) had euthyroidism. There were 1,532 cancer deaths during the 1,034,082 person-years follow-up period. Adjusted for age, gender, body mass index, diabetes, hypertension, dyslipidemia, smoking, alcohol drinking, betel nut chewing, physical activity, income, and education level, the RRs (95% confidence interval) of cancer deaths among subjects with SCH versus euthyroid subjects were 1.51 (1.06 to 2.15). Cancer site analysis revealed a significant increased risk of bone, skin and breast cancer among SCH subjects (RR 2.79, (1.01, 7.70)). The risks of total cancer deaths were more prominent in the aged (RR 1.71, (1.02 to 2.87)), in females (RR 1.69 (1.08 to 2.65)), and in heavy smokers (RR 2.24, (1.19 to 4.21)).Conclusions
Subjects with SCH had a significantly increased risk for cancer mortality among adult Taiwanese. This is the first report to demonstrate the association between SCH and cancer mortality. 相似文献99.
Shin-Ru Shih Tzu-Yun Chu Gadarla Randheer Reddy Sung-Nain Tseng Hsiun-Ling Chen Wen-Fang Tang Ming-sian Wu Jiann-Yih Yeh Yu-Sheng Chao John TA Hsu Hsing-Pang Hsieh Jim-Tong Horng 《Journal of biomedical science》2010,17(1):13
Background
Influenza viruses are a major cause of morbidity and mortality around the world. More recently, a swine-origin influenza A (H1N1) virus that is spreading via human-to-human transmission has become a serious public concern. Although vaccination is the primary strategy for preventing infections, influenza antiviral drugs play an important role in a comprehensive approach to controlling illness and transmission. In addition, a search for influenza-inhibiting drugs is particularly important in the face of high rate of emergence of influenza strains resistant to several existing influenza antivirals.Methods
We searched for novel anti-influenza inhibitors using a cell-based neutralization (inhibition of virus-induced cytopathic effect) assay. After screening 20,800 randomly selected compounds from a library from ChemDiv, Inc., we found that BPR1P0034 has sub-micromolar antiviral activity. The compound was resynthesized in five steps by conventional chemical techniques. Lead optimization and a structure-activity analysis were used to improve potency. Time-of-addition assay was performed to target an event in the virus life cycle.Results
The 50% effective inhibitory concentration (IC50) of BPR1P0034 was 0.42 ± 0.11 μM, when measured with a plaque reduction assay. Viral protein and RNA synthesis of A/WSN/33 (H1N1) was inhibited by BPR1P0034 and the virus-induced cytopathic effects were thus significantly reduced. BPR1P0034 exhibited broad inhibition spectrum for influenza viruses but showed no antiviral effect for enteroviruses and echovirus 9. In a time-of-addition assay, in which the compound was added at different stages along the viral replication cycle (such as at adsorption or after adsorption), its antiviral activity was more efficient in cells treated with the test compound between 0 and 2 h, right after viral infection, implying that an early step of viral replication might be the target of the compound. These results suggest that BPR1P0034 targets the virus during viral uncoating or viral RNA importation into the nucleus.Conclusions
To the best of our knowledge, BPR1P0034 is the first pyrazole-based anti-influenza compound ever identified and characterized from high throughput screening to show potent (sub-μM) antiviral activity. We conclude that BPR1P0034 has potential antiviral activity, which offers an opportunity for the development of a new anti-influenza virus agent. 相似文献100.
Ya Po Kuo Yueh-Lun Lee Yu Hong Tseng Ching-Hua Su Thierry Burnouf Chen Yao Su 《Biologicals》2010,38(1):120-127
Platelet gels (PG) are new topical single-donor blood products which are attracting great interest in regenerative medicine. They are obtained by mixing a platelet-rich plasma fraction with thrombin to generate a fibrin gel enriched in platelet growth factors (GF). The type of thrombin preparation may affect PG reproducibility. We have determined the impact of 14.6% (v/v) ethanol-stabilized thrombin (EHT) on the release of GF by platelets. Various ratios of EHT and platelet concentrates were mixed to obtain from 2.43 to 7.96% ethanol concentration. Platelet-derived growth factor-AB (PDGF-AB), transforming growth factor-ß1 (TGF-ß1), vascular endothelium growth factor (VEGF), epidermal growth factor (EGF), and insulin-like growth factor-1 (IGF-1) were assessed at 5, 120, and 300 min after PG formation. Protein profiles of thrombin and PG releasates were analyzed by SDS-PAGE. The amount of PDGF-AB, TGF-ß1, and VEGF released per platelet decreased significantly (p < 0.05) with increasing ethanol concentrations but, however, not that of EGF. IGF-1 content was stable, consistent with its presence mostly in plasma. SDS-PAGE indicated that ethanol did not affect fibrin formation. In conclusion, ethanol has a significant impact on the amount of GF released by platelets and should be strictly controlled to standardize PG and optimize clinical benefits. 相似文献