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1.
Minh Thac Nguyen Ryan Denniston Hien Thi Thu Nguyen Tuan Anh Hoang Hana Ross Anthony D. So 《PloS one》2014,9(1)
Illicit trade carries the potential to magnify existing tobacco-related health care costs through increased availability of untaxed and inexpensive cigarettes. What is known with respect to the magnitude of illicit trade for Vietnam is produced primarily by the industry, and methodologies are typically opaque. Independent assessment of the illicit cigarette trade in Vietnam is vital to tobacco control policy. This paper measures the magnitude of illicit cigarette trade for Vietnam between 1998 and 2010 using two methods, discrepancies between legitimate domestic cigarette sales and domestic tobacco consumption estimated from surveys, and trade discrepancies as recorded by Vietnam and trade partners. The results indicate that Vietnam likely experienced net smuggling in during the period studied. With the inclusion of adjustments for survey respondent under-reporting, inward illicit trade likely occurred in three of the four years for which surveys were available. Discrepancies in trade records indicate that the value of smuggled cigarettes into Vietnam ranges from $100 million to $300 million between 2000 and 2010 and that these cigarettes primarily originate in Singapore, Hong Kong, Macao, Malaysia, and Australia. Notable differences in trends over time exist between the two methods, but by comparison, the industry estimates consistently place the magnitude of illicit trade at the upper bounds of what this study shows. The unavailability of annual, survey-based estimates of consumption may obscure the true, annual trend over time. Second, as surveys changed over time, estimates relying on them may be inconsistent with one another. Finally, these two methods measure different components of illicit trade, specifically consumption of illicit cigarettes regardless of origin and smuggling of cigarettes into a particular market. However, absent a gold standard, comparisons of different approaches to illicit trade measurement serve efforts to refine and improve measurement approaches and estimates. 相似文献
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3.
R A Van Vliet J S Walton A G Wildeman K J Betteridge A M Gibbins 《Journal of reproduction and fertility》1991,91(1):73-79
Total cellular RNA was isolated from conceptus tissue obtained from 22 superovulated cows 18 days after artificial insemination. Total RNA was also isolated from luteal tissue from 3 cyclic cows 7 and 8 days after oestrus. Luteal and conceptus RNA were simultaneously subjected to formaldehyde-agarose gel electrophoresis and transferred to nitrocellulose by bidirectional diffusion blotting. Northern blots were probed using cDNAs specific for bovine oxytocin and bovine beta-actin gene sequences. Hybridization of the oxytocin cDNA to RNA was consistently observed on autoradiographs as a 0.6 kilobase (kb) band in lanes containing corpus luteum RNA, but was not detected in lanes containing conceptus RNA. The presence of conceptus RNA on the blots was confirmed by hybridization of the actin cDNA to conceptus RNA, which resulted in a 2.0 kb band on autoradiographs. These results suggest that oxytocin is not synthesized by the bovine conceptus on Day 18 of gestation. 相似文献
4.
J M Scodras K J Betteridge B A Croy I B Johnstone D Rieger 《Journal of reproduction and fertility》1991,92(2):483-494
The ability of purified preparations of platelet-activating factor (PAF), from three different suppliers, to induce thrombocytopaenia in mice after splenectomy and to activate mouse platelets in vitro was examined. Although the PAF preparations were potent activators of horse and cow platelets in vitro, injections of up to 1 microgram PAF failed to elicit thrombocytopaenia responses in either CD1 or Swiss Webster random-bred mice. However, when thrombin was injected into Swiss Webster mice, a dose-dependent decrease in the concentration of platelets was observed. Furthermore, isolated platelets from these strains and from 3 inbred lines (C3H/He, BALB/c, C57BL/6) of mice, were not aggregated by PAF in vitro but were sensitive to adenosine diphosphate and thrombin. No change in circulating platelet concentrations was observed over the initial 7 days of gestation in intact Swiss Webster and C57BL/6 or splenectomized C57BL/6 mice, suggesting either an absence of PAF production during early pregnancy in these strains or insensitivity of their platelets to PAF. These results suggest that many mouse strains are unsuitable for the bioassay of PAF. 相似文献
5.
Bui Hai Ninh Duong Thi Dung Bui Huu Tai Pham Hai Yen Nguyen Xuan Nhiem Truong Thi Thu Hien Do Thi Trang Nguyen Van Tuyen Le Tuan Anh Nguyen Thi Hoai Phan Van Kiem 《化学与生物多样性》2023,20(3):e202201048
A new isopropyl chromone ( 1 ) and a new flavanone glucoside ( 2 ) together with eleven known compounds ( 3–13 ) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one ( 1 ), 5,7-dihydroxyflavanone 7-O-β-D-(6′′-O-galloylglucopyranoside) ( 2 ), strobopinin ( 3 ), demethoxymatteucinol ( 4 ), pinocembrin-7-O-β-D-glucopyranoside ( 5 ), (2S)-hydroxynaringenin-7-O-β-D-glucopyranoside ( 6 ), afzelin ( 7 ), quercetin ( 8 ), kaplanin ( 9 ), endoperoxide G3 ( 10 ), grasshopper ( 11 ), vomifoliol ( 12 ), litseagermacrane ( 13 ) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1 , 2 , 5 , 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, NG-monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 32.50±1.00 μM. 相似文献
6.
Nguyen Dinh Luyen Le Mai Huong Nguyen Thi Thu Ha Nguyen Thanh Tra Le Thi Tu Anh Nguyen Van Tuyen Katalin Posta Ninh The Son Hai Pham-The 《化学与生物多样性》2023,20(2):e202200456
The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50–100 μg/mL). In α-glucosidase inhibitory assay, they induced the IC50 values of 1.00-2.53 μg/mL were better than positive control acarbose (169.80 μg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors. 相似文献
7.
Doan Minh Sang Ik Ho Na Dr. Duong Tien Anh Do Thi Mai Dung Nguyen Thi Thu Hang Nguyen T. Phuong-Anh Assoc. Prof. Dr. Pham-The Hai Assoc. Prof. Dr. Dao Thi Kim Oanh Dr. Truong Thanh Tung Soo Jung Lee Joo Hee Kwon Prof. Dr. Jong Soon Kang Prof. Dr. Sang-Bae Han Assoc. Prof. Dr. Dinh Thi Thanh Hai Prof. Dr. Nguyen-Hai Nam 《化学与生物多样性》2023,20(5):e202201030
Herein, we report the design, synthesis and evaluation of novel (E)-3-(3-oxo-4-substituted-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)-N-hydroxypropenamides ( 4 a – i , 7 a – g ) targeting histone deacetylases. Three human cancer cell lines were used to test the cytotoxicity of the synthesized compounds (SW620, colon; PC-3, prostate; NCI−H23, lung cancer); inhibitory activity towards HDAC; anticancer activity; as well as their impact on the cell cycle and apoptosis. As a result, compounds 4 a – i bearing the alkyl substituents seemed to be less potent than the benzyl-containing compounds 7 a – g in all biological assays. Compounds 7 e – f were found to be the most active HDAC inhibitors with IC50 of 1.498±0.020 μM and 1.794±0.159 μM, respectively. In terms of cytotoxicity and anticancer assay, 7 e and 7 f also showed good activity with IC50 values in the micromolar range. In addition, the cell cycle and apoptosis of SW620 were affected by compound 7 f in almost a similar manner to that of reference compound SAHA. Docking assays were carried out for analysis the binding mode and selectivity of this compound toward 8 HDAC isoforms. Overall, our data confirmed that the inhibition of HDAC plays a pivotal role in their anticancer activity. 相似文献
8.
The oviducts of 24 mares were examined to determine the site of retention of unfertilized eggs. The ampullary-isthmic junction regions of 42 of the 48 oviducts were serially sectioned and examined histologically. The remaining parts of the oviducts were flushed and the flushings searched microscopically. Of 45 eggs located, 40 were in the sectioned segments of 24 oviducts and only 5 were in the flushings. All but one of the sectioned segments contained prominent masses of material obstructing the lumen, but these were apparently not the direct cause of egg retention since eggs were found on both sides of them. 相似文献
9.
A. J. Nixon M. P. Gurnsey K. Betteridge R. J. Mitchell R. A. S. Welch 《Journal of Zoology》1991,224(4):589-598
Hair follicle activity and fibre growth were studied using histological sections from the skin of five adult feral does sampled every four weeks for 18 months. The main period of guard hair growth in primary follicles was from November to April. Secondary follicles grew fine, long, nonmedullated fibres (cashmere) from December to June. Shedding of these fibres from secondary follicles had commenced by July and cashmere was absent from the fleece by November. From September to December a subsidiary hair cycle occurred in many secondary follicles which produced minute (vellus) fibres, less than 2.4 mm in length. Some secondary follicles probably shed their cashmere fibres and remain quiescent over spring. Annual pelage changes were therefore achieved with one main growth period, although many secondary follicles underwent another brief hair cycle in spring. 相似文献
10.
Staphylococcus aureus Lpl protein triggers human host cell invasion via activation of Hsp90 receptor
Paula M. Tribelli Arif Luqman Minh‐Thu Nguyen Johannes Madlung Sook‐Ha Fan Boris Macek Peter Sass Katharina Bitschar Birgit Schittek Dorothee Kretschmer Friedrich Gtz 《Cellular microbiology》2020,22(1)
Staphylococcus aureus is a facultative intracellular pathogen. Recently, it has been shown that the protein part of the lipoprotein‐like lipoproteins (Lpls), encoded by the lpl cluster comprising of 10 lpls paralogue genes, increases pathogenicity, delays the G2/M phase transition, and also triggers host cell invasion. Here, we show that a recombinant Lpl1 protein without the lipid moiety binds directly to the isoforms of the human heat shock proteins Hsp90α and Hsp90ß. Synthetic peptides covering the Lpl1 sequence caused a twofold to fivefold increase of S. aureus invasion in HaCaT cells. Antibodies against Hsp90 decrease S. aureus invasion in HaCaT cells and in primary human keratinocytes. Additionally, inhibition of ATPase function of Hsp90 or silencing Hsp90α expression by siRNA also decreased the S. aureus invasion in HaCaT cells. Although the Hsp90ß is constitutively expressed, the Hsp90α isoform is heat‐inducible and appears to play a major role in Lpl1 interaction. Pre‐incubation of HaCaT cells at 39°C increased both the Hsp90α expression and S. aureus invasion. Lpl1‐Hsp90 interaction induces F‐actin formation, thus, triggering an endocytosis‐like internalisation. Here, we uncovered a new host cell invasion principle on the basis of Lpl‐Hsp90 interaction. 相似文献