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991.
Seema Mihrshahi Antonio Montresor Dang Thi Cam Thach Beverley-Ann Biggs 《International journal for parasitology》2009,39(9):1037-1043
Soil-transmitted helminth (STH) infections are endemic in northern Viet Nam where the climate and agricultural practices, such as the use of human excreta as fertiliser and the use of wastewater for irrigation, favour transmission. An intervention was conducted in Yen Bai Province, north-west Viet Nam, to measure the effectiveness of single dose albendazole (400 mg) administered every 4 months for reducing the prevalence of STH infections in women of reproductive age. Stool samples were collected from women before the intervention and 3 and 12 months post-intervention. Information on a range of demographic and socio-economic variables was also collected to measure the major risk factors for high STH burden in this area. The prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura infection in the baseline sample of 366 women were 76.2%, 19.2% and 29.1%, respectively. In the women who were surveyed at baseline and again at 3 and 12 months after the intervention (n = 118) cure rates were 71.3% for hookworm, 87.0% for A. lumbricoides and 81.4% for T. trichiura by the end of the 12 month study period (i.e. after three doses of albendazole). The main risk factor for hookworm infection was if women worked outside (odds ratio (OR) = 3.2 (95% Confidence Interval (CI) 1.6-6.2), P = 0.001) and the major risk factor for A. lumbricoides and T. trichiura infection was a lack of education. Low educational attainment was also the strongest risk factor for co-infection with all three species of STH (OR = 7.5 (95% CI 3.4-16.4), P < 0.001). The high rates of hookworm infection in this area of Viet Nam and the high cure rates for all three species of STH with 4 monthly albendazole treatment suggest that this programme should be expanded to all endemic areas in Viet Nam. The study also highlights the important contribution of education to women’s health. 相似文献
992.
993.
Background
Previous meta-analyses reported that probiotics improve the effectiveness of Helicobacter pylori (H. pylori) eradication during antibiotic therapy, while results regarding a possible reduction of side effects remained inconclusive. Moreover, the effectiveness of different strains of probiotics has not been studied so far. It is further conceivable that probiotics will produce additional effects only if antibiotics are relatively ineffective.Methods
This meta-analysis includes eligible randomized controlled trials examining effects of probiotics supplementation on eradication rates (ER) and side effects, published up to May 2014. Sub-group analysis was performed to compare different probiotic strains and antibiotic therapies with different effectiveness in controls (ER <80% vs.>80%). Publication bias was assessed with funnel plots and Harbord''s test. The quality of the trials was assessed with the Cochrane risk of bias tool.Results
Thirty-three RCTs involving a total of 4459 patients met the inclusion criteria in case of eradication rates of which 20 assessed total side effects in addition. Overall, the pooled eradication rate in probiotics supplementation groups was significantly higher than in controls (ITT analysis: RR 1.122, 95% CI 1.086–1.159, PP analysis: RR 1.114, 95% CI 1.070–1.159). Sub group-analysis could, however, confirm this finding only for four individual strains (Lactobacillus acidophilus, Lactobacillus casei DN-114001, Lactobacillus gasseri, and Bifidobacterium infantis 2036) and for relatively ineffective antibiotic therapies. There was a significant difference between groups in the overall incidence of side effects (RR 0.735, 95% CI 0.598–0.902). This result was, however, only confirmed for non-blinded trials.Conclusions
The pooled data suggest that supplementation with specific strains of probiotics compared with eradication therapy may be considered an option for increasing eradication rates, particularly when antibiotic therapies are relatively ineffective. The impact on side effects remains unclear and more high quality trials on specific probiotic strains and side effects are thus needed. 相似文献994.
Nuclear import of the retrotransposon Tf1 is governed by a nuclear localization signal that possesses a unique requirement for the FXFG nuclear pore factor Nup124p 下载免费PDF全文
Retroviruses, such as human immunodeficiency virus, that infect nondividing cells generate integration precursors that must cross the nuclear envelope to reach the host genome. As a model for retroviruses, we investigated the nuclear entry of Tf1, a long-terminal-repeat-containing retrotransposon of the fission yeast Schizosaccharomyces pombe. Because the nuclear envelope of yeasts remains intact throughout the cell cycle, components of Tf1 must be transported through the envelope before integration can occur. The nuclear localization of the Gag protein of Tf1 is different from that of other proteins tested in that it has a specific requirement for the FXFG nuclear pore factor, Nup124p. Using extensive mutagenesis, we found that Gag contained three nuclear localization signals (NLSs) which, when included individually in a heterologous protein, were sufficient to direct nuclear import. In the context of the intact transposon, mutations in the NLS that mapped to the first 10 amino acid residues of Gag significantly impaired Tf1 retrotransposition and abolished nuclear localization of Gag. Interestingly, this NLS activity in the heterologous protein was specifically dependent upon the presence of Nup124p. Deletion analysis of heterologous proteins revealed the surprising result that the residues in Gag with the NLS activity were independent from the residues that conveyed the requirement for Nup124p. In fact, a fragment of Gag that lacked NLS activity, residues 10 to 30, when fused to a heterologous protein, was sufficient to cause the classical NLS of simian virus 40 to require Nup124p for nuclear import. Within the context of the current understanding of nuclear import, these results represent the novel case of a short amino acid sequence that specifies the need for a particular nuclear pore complex protein. 相似文献
995.
Hai Dang Vu 《Ocean Development & International Law》2013,44(2):145-169
The Chinese annual fishing ban in the northwestern area of the South China Sea has been a cause for tension between Vietnam and China in recent years. This article advocates for the replacement of this unilateral fishing ban with a bilateral network of marine protected areas between China and Vietnam. Such a network, if properly implemented, could not only help to preserve the living resources of the South China Sea, but also contribute toward decreasing the tension between the two countries. 相似文献
996.
Dang HT Lee HJ Yoo ES Hong J Bao B Choi JS Jung JH 《Bioorganic & medicinal chemistry》2008,16(24):10228-10235
In an effort to develop new anti-inflammatory agents, methyl jasmonate analogues (2-20) were synthesized and evaluated for their inhibitory effects on the production of pro-inflammatory mediators (NO, IL-6, and TNF-alpha) in lipopolysaccharide (LPS)-activated RAW264.7 murine macrophage cells. The introduction of an enone functionality to the structure of a plant hormone (1) rendered the product (2) a significant anti-inflammatory activity. Analogues further derived from 2 (7, 9, 13, and 15) exhibited even more enhanced activity, and these compounds were much more potent than natural anti-inflammatory prostaglandins (PGA(1), PGA(2), and 15-deoxy-Delta(12,14)-PGJ(2)). Among them, compounds 9 and 15 showed the highest potency, while compounds 7 and 13 would be more desirable with respect to safety. This is the first study demonstrating the anti-inflammatory potential of jasmonate derivatives, and the present results suggest that alpha-haloenone jasmonates (7, 9, 13, and 15) may serve as potential anti-inflammatory leads. 相似文献
997.
998.
Nadjet Mostefa Prof. Dr. Noureddine Djebli Dr. Pham Ngoc Khanh Nguyen Xuan Ha Hoang Thi Ngoc Anh Vu Thi Ha Dr. Tran Thu Huong Dr. Dang Viet Anh Prof. Dr. Nguyen Manh Cuong 《化学与生物多样性》2023,20(5):e202201051
The stilbene-rich acetone fraction in high yield (6.6 %, PEAS) of Passiflora edulis Sims was prepared and evaluated for neuroprotective activity in murine Alzheimer's disease model induced by aluminum chloride and D-galactose. The phytochemical and HPLC-DAD-MS analysis of the polyphenolic stilbene-rich acetone fraction showed that it contained different stilbenes including trans-piceatannol, scirpusins A−B and cassigarol E. The total phenolic content (TPC) of PEAS was 413.87±1.71 mg GAE eqv/g. The neuroprotective activity of PEAS is typically presented in the Morris water maze-reference Spatial Memory test, where the Alzheimer's mice treated at 100 mg/kg (Alz-ED1) and 200 mg/kg (Alz-ED2) spent less than 47 % and 66 % of the time, respectively, than the Alzheimer's model mice (Alz). Two simple stilbenes, trans-piceatannol and trans-resveratrol, showed selectively inhibitory activity in silico against acetylcholinesterase (AChE). Two stilbene dimers, cassigarol E and scirpusin A, exhibited low nanomolar inhibitory potential against AChE and butyrylcholinesterase (BChE), significantly lower than those of the positive control, donepezil and tacrine. These findings suggest that the stilbenes from P. edulis seeds, particularly the stilbene dimers, warrant further investigation as potential neuroprotective candidates in the prevention of cognitive deficits associated with Alzheimer's disease. 相似文献
999.
Molecular and antigenic nature of isolated Sm 总被引:6,自引:0,他引:6
H Dang M Fischbach E Lerner N Talal 《Journal of immunology (Baltimore, Md. : 1950)》1983,130(6):2782-2785
The Sm antigen was isolated and purified from calf thymus nuclear extract by affinity chromatography. The affinity columns were made with serum antibodies from an SLE patient or an anti-Sm monoclonal antibody derived from a hybridoma cell line. Proteins eluted from these two columns had m.w. of 58,000 and 35,000 by SDS polyacrylamide gel electrophoresis. The natural conformation of this antigen appears to be 95,000 in m.w. with the 58,000 particle containing the Sm antigenic determinant. The affinity column-purified antigen detected by the human anti-Sm antibodies is also recognized by anti-Sm antibodies in murine lupus serum, as shown by solid-phase radioimmunoassay. This study 1) demonstrates the molecular and antigenic nature of the Sm antigen and 2) compares the anti-Sm binding capabilities of antibody populations present in sera from SLE patients and from MRL lpr/lpr mice. 相似文献
1000.