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101.
Gloria Mwanjali Charles Kihamia Deodatus Vitalis Conatus Kakoko Faustin Lekule Helena Ngowi Maria Vang Johansen Stig Milan Thamsborg Arve Lee Willingham III 《PLoS neglected tropical diseases》2013,7(3)
Background
Taenia solium cysticercosis/taeniosis is emerging as a serious public health and economic problem in many developing countries. This study was conducted to determine prevalence and risk factors of human T. solium infections in Mbeya Region, Tanzania.Methods and Findings
A cross-sectional survey was conducted in 13 villages of Mbozi district in 2009. Sera of 830 people (mean 37.9±11.3 years (SD); 43% females) were tested for circulating cysticerci antigen (Ag-ELISA) and antibody (Ab-ELISA). A subset of persons found seropositive by Ag-ELISA underwent computed tomography (CT) scan of the brain for evidence of neurocysticercosis. Stool samples from 820 of the same participants were tested for taeniosis by copro-antigens (copro-Ag-ELISA) and formol-ether concentration technique. Cases of T. solium taeniosis were confirmed serologically by EITB assay (rES38). A questionnaire was used for identification of risk factors. Active cysticercosis by positive Ag-ELISA was found in 139 (16.7%) persons while anti-cysticercal antibodies were detected in 376 (45.3%) persons by Ab-ELISA. Among 55 persons positive for Ag-ELISA undergoing CT scan, 30 (54.6%) were found to have structures in the brain suggestive of neurocysticercosis. Using faecal analysis, 43 (5.2%) stool samples tested positive for taeniosis by copro-Ag-ELISA while Taenia eggs were detected in 9 (1.1%) stool samples by routine coprology. Antibodies specifically against adult T. solium were detected in 34 copro-Ag-ELISA positive participants by EITB (rES38) indicating T. solium taeniosis prevalence of 4.1%. Increasing age and hand washing by dipping in contrast to using running water, were found associated with Ag-ELISA seropositivity by logistic regression. Gender (higher risk in females) and water source were risk factors associated with Ab-ELISA seropositivity. Reported symptoms of chronic severe headaches and history of epileptic seizures were found associated with positive Ag-ELISA (p≤0.05).Conclusion
The present study indicates T. solium infection in humans is highly endemic in the southern highlands of Tanzania. 相似文献102.
103.
Jakob Hedegaard Kasper Thorsen Mette Katrine Lund Anne-Mette K. Hein Stephen Jacques Hamilton-Dutoit S?ren Vang Iver Nordentoft Karin Birkenkamp-Demtr?der Mogens Kruh?ffer Henrik Hager Bjarne Knudsen Claus Lindbjerg Andersen Karina Dalsgaard S?rensen Jakob Skou Pedersen Torben Falck ?rntoft Lars Dyrskj?t 《PloS one》2014,9(5)
104.
105.
Yin S Dong Y Li J Fan L Wang L Lu J Vang O Hu H 《Apoptosis : an international journal on programmed cell death》2012,17(4):388-399
ABT-737, a novel small molecule inhibitor of Bcl-2 family proteins, holds great promise to complement current cancer therapies.
However many types of solid cancer cells are resistant to ABT-737. One practical approach to improve its therapeutic efficacy
is to combine with the agents that can overcome such resistance to restore the sensitivity. In the present study, a second-generation
selenium compound methylseleninic acid (MSeA) synergistically sensitized MDA-MB-231 human breast cancer cells, HT-29 human
colon cancer cells and DU145 human prostate cancer cells to apoptosis induction by ABT-737, as evidenced by greater than additive
enhancement of Annexin V/FITC positive (apoptotic) cells and activation of multiple caspases and PARP cleavage. Mechanistic
investigation demonstrated that MSeA significantly decreased basal Mcl-1 expression and ABT-737-induced Mcl-1 expression.
Knocking down of Mcl-1 with RNAi approach supported the functional significance of this molecular target. More importantly,
we identified inactivation of Bad by phosphorylation on ser-136 and ser-112 as a novel mechanism involved in ABT-737 resistance,
which can be overcome by combining with MSeA. In addition, we found that expression of Bax was required for the efficient
execution of synergistic sensitization. Our findings, for the first time, provide a strong mechanistic rationale for developing
MSeA as a novel sensitizing agent of ABT-737. 相似文献
106.
Alberto Pondja Luís Neves James Mlangwa Sónia Afonso José Fafetine Arve Lee Willingham III Stig Milan Thamsborg Maria Vang Johansen 《PLoS neglected tropical diseases》2010,4(2)
Taenia solium is an important zoonosis in many developing countries. Cysticercosis poses a serious public health risk and incurs sizeable economic losses to pig production. Because data on the epidemiology of porcine cysticercosis in Mozambique are scarce, the present study was conducted to determine the prevalence and risk factors for porcine cysticercosis. A cross-sectional survey was carried out in 11 villages in Angónia district, Tete province in northwestern Mozambique. Between September and November, 2007, a total of 661 pigs were tested serologically and examined by tongue inspection. Serum samples were tested for the presence of circulating parasite antigen using a monoclonal antibody-based sandwich enzyme-linked immunosorbent assay (Ag-ELISA). In addition, a questionnaire survey to collect information on pig production, occurrence and transmission of porcine cysticercosis, risk factors and awareness of porcine cysticercosis was conducted in the selected households from which pigs were sampled. Two hundred thirty-one samples (34.9%) were found positive by the Ag-ELISA, while by tongue inspection on the same animals cysticerci were detected in 84 pigs (12.7%). Increasing age (OR = 1.63; 95% CI = 1.13–2.37) and free-range pig husbandry system (OR = 3.81; 95% CI = 2.08–7.06) were important risk factors for porcine cysticercosis in the district. The present findings indicate that porcine cysticercosis is endemic in the region, and that increasing pig age and pig husbandry practices contribute significantly to porcine cysticercosis transmission. Further epidemiological studies on the prevalence and transmission of porcine cysticercosis in rural communities in Mozambique are needed to enable collection of more baseline data and implementation of effective control strategies within the country. 相似文献
107.
Vang KB Yang J Mahmud SA Burchill MA Vegoe AL Farrar MA 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(5):3285-3290
Common gamma chain (gammac)-receptor dependent cytokines are required for regulatory T cell (Treg) development as gammac(-/-) mice lack Tregs. However, it is unclear which gammac-dependent cytokines are involved in this process. Furthermore, thymic stromal lymphopoietin (TSLP) has also been suggested to play a role in Treg development. In this study, we demonstrate that developing CD4(+)Foxp3(+) Tregs in the thymus express the IL-2Rbeta, IL-4Ralpha, IL-7Ralpha, IL-15Ralpha, and IL-21Ralpha chains, but not the IL9Ralpha or TSLPRalpha chains. Moreover, only IL-2, and to a much lesser degree IL-7 and IL-15, were capable of transducing signals in CD4(+)Foxp3(+) Tregs as determined by monitoring STAT5 phosphorylation. Likewise, IL-2, IL-7, and IL-15, but not TSLP, were capable of inducing the conversion of CD4(+)CD25(+)Foxp3(-) thymic Treg progenitors into CD4(+)Foxp3(+) mature Tregs in vitro. To examine this issue in more detail, we generated IL-2Rbeta(-/-) x IL-7Ralpha(-/-) and IL-2Rbeta(-/-) x IL-4Ralpha(-/-) mice. We found that IL-2Rbeta(-/-) x IL-7Ralpha(-/-) mice were devoid of Tregs thereby recapitulating the phenotype observed in gammac(-/-) mice; in contrast, the phenotype observed in IL-2Rbeta(-/-) x IL-4Ralpha(-/-) mice was comparable to that seen in IL-2Rbeta(-/-) mice. Finally, we observed that Tregs from both IL-2(-/-) and IL-2Rbeta(-/-) mice show elevated expression of IL-7Ralpha and IL-15Ralpha chains. Addition of IL-2 to Tregs from IL-2(-/-) mice led to rapid down-regulation of these receptors. Taken together, our results demonstrate that IL-2 plays the predominant role in Treg development, but that in its absence the IL-7Ralpha and IL-15Ralpha chains are up-regulated and allow for IL-7 and IL-15 to partially compensate for loss of IL-2. 相似文献
108.
Damir Krunic Sharareh Moshir Karin M. Greulich-Bode Reynel Figueroa Ana Cerezo Hermann Stammer Hans-Jürgen Stark Steven G. Gray Kirsten Vang Nielsen Wolfgang Hartschuh Petra Boukamp 《生物化学与生物物理学报:疾病的分子基础》2009,1792(4):297-308
Telomerase- and telomere length regulation in normal human tissues is still poorly understood. We show here that telomerase is expressed in the epidermis in situ independent of age but was repressed upon the passaging of keratinocytes in monolayer culture. However, when keratinocytes were grown in organotypic cultures (OTCs), telomerase was re-established, indicating that telomerase activity is not merely proliferation-associated but is regulated in a tissue context-dependent manner in human keratinocytes. While not inducible by growth factors, treatment with the histone deacetylation inhibitor FK228 restored telomerase activity in keratinocytes grown in monolayer cultures. Accordingly, CHIP analyses demonstrated an acetylated, active hTERT promoter in the epidermis in situ and in the epidermis of OTCs but a deacetylated, silenced hTERT promoter with subsequent propagation in monolayer culture suggesting that histone acetylation is part of the regulatory program to guarantee hTERT expression/telomerase activity in the epidermis. In agreement with the loss of telomerase activity, telomeres shortened during continuous propagation in monolayer culture by an average of ~ 70 base pairs (bp) per population doubling (pd). However, telomere erosion varied strongly between different keratinocyte strains and even between individual cells within the same culture, thereby arguing against a defined rate of telomere loss per replication cycle. In the epidermis in situ, as determined from early-passage keratinocytes and tissue sections from different age donors, we calculated a telomere loss of only ~ 25 bp per year. Since we determined the same rate for the non-regenerating melanocytes and dermal fibroblasts, our data suggest that in human epidermis telomerase is a protective mechanism against excessive telomere loss during the life-long regeneration. 相似文献
109.
Maya F. Kotturi Jason Botten John Sidney Huynh-Hoa Bui Lori Giancola Matt Maybeno Josie Babin Carla Oseroff Valerie Pasquetto Jason A. Greenbaum Bjoern Peters Joey Ting Danh Do Lo Vang Jeff Alexander Howard Grey Michael J. Buchmeier Alessandro Sette 《PLoS pathogens》2009,5(12)
Arenaviruses are the causative pathogens of severe hemorrhagic fever and aseptic meningitis in humans, for which no licensed vaccines are currently available. Pathogen heterogeneity within the Arenaviridae family poses a significant challenge for vaccine development. The main hypothesis we tested in the present study was whether it is possible to design a universal vaccine strategy capable of inducing simultaneous HLA-restricted CD8+ T cell responses against 7 pathogenic arenaviruses (including the lymphocytic choriomeningitis, Lassa, Guanarito, Junin, Machupo, Sabia, and Whitewater Arroyo viruses), either through the identification of widely conserved epitopes, or by the identification of a collection of epitopes derived from multiple arenavirus species. By inoculating HLA transgenic mice with a panel of recombinant vaccinia viruses (rVACVs) expressing the different arenavirus proteins, we identified 10 HLA-A02 and 10 HLA-A03-restricted epitopes that are naturally processed in human antigen-presenting cells. For some of these epitopes we were able to demonstrate cross-reactive CD8+ T cell responses, further increasing the coverage afforded by the epitope set against each different arenavirus species. Importantly, we showed that immunization of HLA transgenic mice with an epitope cocktail generated simultaneous CD8+ T cell responses against all 7 arenaviruses, and protected mice against challenge with rVACVs expressing either Old or New World arenavirus glycoproteins. In conclusion, the set of identified epitopes allows broad, non-ethnically biased coverage of all 7 viral species targeted by our studies. 相似文献
110.
Osorio-Córdoba J LL Rodriguez-Verástegui F Díaz de León-Sánchez E Bosquez-Molina JR Verde-Calvo HB Escalona-Buendía LJ Pérez-F lores C Pelayo-Zaldívar 《Phyton》2015,84(2):375-384
Cactus stems, the cladodes of Opuntia spp. cacti, are consumed in Mexico and other countries due to their fresh and herbaceous flavor, and because of their widely known nutraceutical benefits. In order to extend the postharvest life of this vegetable, the effect of a modified atmosphere packaging (MAP) was studied in cactus stems of the cultivar Atlixco stored at 4 ± 1 °C for 20 days under three types of atmospheres: (1) air (passive atmosphere), (2) 5 kPa O2 + 4 kPa CO2, and (3) N2. During storage, the titratable acidity decreased and the color of cladodes became darker and less green; however, the 5 kPa O2 + 4 kPa CO2 atmosphere was able to preserve both quality characteristics. All modified atmospheres reduced weight loss (from 8 to <2%) and the symptoms of chilling injury, and this physiological disorder appeared earlier in controls than in MAP-stored cladodes. The levels of fermentation metabolites were low in all three evaluated atmospheres. Because of this, only cladodes stored under the N2 atmosphere were selected for furthersensory analysis of the MAP effect on odor perception as evaluated by a trained panel. Results indicated that there was no detrimental effect (atypical odors) of MAP on this sensory characteristic. We conclude that cultivar Atlixco is suitable for preservation using MAP technology. 相似文献