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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
2.
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
3.
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
4.
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
5.
Summary Quantities of disencrusted sub-elementary cellulose fibrils from the cell wall of rose cells culturedin vitro were prepared. Following an X-ray and electron diffraction analysis, these fibrils gave a cellulose diffraction pattern which presented only two strong equatorial diffraction spacings at 0.409 and 0.572 nm indicating that the fibrils have a crystalline structure resembling that of cellulose IVI. This observation is best explained in terms of a lateral disorganization of the cellulose chains within the fibrils. This disorganization cannot be eliminated and is connected with the small width of the fibrils which contain from 12 to 25 cellulose chains only. In these fibrils, most of the cellulose chains are superficial and not locked with neighboring chains in a tight hydrogen bond system as in thicker cellulose microfibrils. 相似文献
6.
Summary Electron diffraction patterns have been obtained from selected areas of disencrusted microfibrils isolated from the primary cell wall of cotton fibers. The resultant fiber diagram has the same meridional repeat distance as a corresponding pattern of secondary wall microfibrils but differs markedly in the equatorial reflections. The primary wall diagram displays only two strong equatorial reflections centered at 0.570 nm and 0.416 nm. The similarity of these spacings with those of cellulose IV suggests that the crystalline structure of the primary wall cellulose is similar to that of cellulose IVI and is best explained in term of native cellulose I crystals having good longitudinal coherence (i.e., coherence along the length of the microfibrils) but with poor lateral organization of the network of inter chain hydrogen bonds. Similar results were also obtained for other primary wall specimens. 相似文献
7.
Kinetic analysis of the activation of transducin by photoexcited rhodopsin. Influence of the lateral diffusion of transducin and competition of guanosine diphosphate and guanosine triphosphate for the nucleotide site. 总被引:1,自引:0,他引:1 下载免费PDF全文
The activation of transducin (T) by photoexcited rhodopsin (R*) is kinetically dissected within the framework of Michaelis-Menten enzymology, taking transducin as substrate of the enzyme R*. The light scattering "release" signal (Vuong, T.M., M. Chabre, and L. Stryer, 1984, Nature (Lond.). 311:659-661) was used to monitor the kinetics of transducin activation at 20 degrees C. In addition, the influence of nonuniform distributions of R* on these activation kinetics is also explored. Sinusoidal patterns of R* were created with interference fringes from two crossed laser beams. Two characteristic times were extracted from the Michaelis-Menten analysis: t(form), the diffusion-related time needed to form the enzyme-substrate R*-transducin is 0.25 +/- 0.1 ms, and T(cat), the time taken by R* to perform the chemistry of catalysis on transducin is 1.2 +/- 0.2 ms, in the absence of added guanosine diphosphate (GDP) and at saturating levels of guanosine triphosphate (GTP). With t(form) being but 20% of the total activation time t(form) + t(cat), transducin activation by R* is not limited by lateral diffusion. This is further borne out by the observation that uniform and sinusoidal patterns of R* elicited release signals of indistinguishable kinetics. When (GDP) = (GTP) = 500 microM, t(cat) is lengthened twofold. As the in vivo GDP and GTP levels are comparable, the exchange of nucleotides may well be the rate-limiting process. 相似文献
8.
Adult-type rhabdomyoma of the palate. Cytologic presentation of two cases with histologic and immunologic study 总被引:1,自引:0,他引:1
P N Vuong Y Neveux A Balaton L Pham-Thominet S Houissa-Vuong M F Schoonaert J P Fombeur 《Acta cytologica》1990,34(3):413-419
The cytologic presentations of two adult-type rhabdomyomas of the soft palate are reported. Fine needle aspiration smears of the lesions contained globular tumor cells that had striations and intracytoplasmic rod-shaped inclusions. These inclusions, corresponding to hypertrophied Z bands, were pathognomonic of rhabdomyoma tissue. The cytologic diagnosis was confirmed by histologic and immunologic studies in both cases. The cytologic preparations fixed in alcohol or air dried did not show the "spiderweb cells" observed in the histologic sections of tissue fragments fixed in formaldehyde; this clearly illustrates that the morphology of the cells of this tumor depends primarily on the specimen preparation technique used. These cases suggest that aspiration cytology can establish the diagnosis of this benign tumor of striated muscle, for which total surgical removal is usually sufficient to effect a cure. The differential diagnosis is discussed in detail. 相似文献
9.
Jeffry Reidler Vernon T. Oi William Carlsen T.Minh Vuong Israel Pecht Leonard A. Herzenberg Lubert Stryer 《Journal of molecular biology》1982,158(4):739-746
The rotational motions of monoclonal mouse anti-dansyl immunoglobulins were studied by nanosecond fluorescence emission anisotropic spectroscopy using a mode-locked argon-ion laser as the pulsed excitation source. Three homogeneous antibodies of the immunoglobulin Gl (IgGl) subclass containing different V regions were prepared. The fluorescence emission maxima of these antibodies (designated as DNS1, DNS2 and DNS3) are at 515, 480 and 500 nm, respectively. Their mean rotational correlation times, 〈φ〉, are 84, 109 and 96 ns, respectively. The binding of protein A or a monoclonal anti-allotype antibody to the Fc unit of DNS1 increased 〈φ〉 to 142 and 150 ns, respectively, whereas reduction of the disulfide bond between the heavy chains decreased 〈φ〉 to 48 ns. These nanosecond measurements show that the rotational motion of the Fab arms in mouse IgGl is restricted. 相似文献
10.