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91.
Anna Martinez Marie C. M. Halliez El Moukhtar Aliouat Magali Chabé Annie Standaert-Vitse Emilie Fréalle Nausicaa Gantois Muriel Pottier Anthony Pinon Eduardo Dei-Cas Cécile-Marie Aliouat-Denis 《PloS one》2013,8(11)
Pneumocystis organisms are airborne opportunistic pathogens that cannot be continuously grown in culture. Consequently, the follow-up of Pneumocystis stage-to-stage differentiation, the sequence of their multiplication processes as well as formal identification of the transmitted form have remained elusive. The successful high-speed cell sorting of trophic and cystic forms is paving the way for the elucidation of the complex Pneumocystis life cycle. The growth of each sorted Pneumocystis stage population was followed up independently both in nude rats and in vitro. In addition, by setting up a novel nude rat model, we attempted to delineate which cystic and/or trophic forms can be naturally aerially transmitted from host to host. The results showed that in axenic culture, cystic forms can differentiate into trophic forms, whereas trophic forms are unable to evolve into cystic forms. In contrast, nude rats inoculated with pure trophic forms are able to produce cystic forms and vice versa. Transmission experiments indicated that 12 h of contact between seeder and recipient nude rats was sufficient for cystic forms to be aerially transmitted. In conclusion, trophic- to cystic-form transition is a key step in the proliferation of Pneumocystis microfungi because the cystic forms (but not the trophic forms) can be transmitted by aerial route from host to host. 相似文献
92.
Background
Dengue poses a substantial economic and disease burden in Southeast Asia (SEA). Quantifying this burden is critical to set policy priorities and disease-control strategies.Methods and Findings
We estimated the economic and disease burden of dengue in 12 countries in SEA: Bhutan, Brunei, Cambodia, East-Timor, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Viet Nam. We obtained reported cases from multiple sources—surveillance data, World Health Organization (WHO), and published studies—and adjusted for underreporting using expansion factors from previous literature. We obtained unit costs per episode through a systematic literature review, and completed missing data using linear regressions. We excluded costs such as prevention and vector control, and long-term sequelae of dengue. Over the decade of 2001–2010, we obtained an annual average of 2.9 million (m) dengue episodes and 5,906 deaths. The annual economic burden (with 95% certainty levels) was US$950m (US$610m–US$1,384m) or about US$1.65 (US$1.06–US$2.41) per capita. The annual number of disability-adjusted life years (DALYs), based on the original 1994 definition, was 214,000 (120,000–299,000), which is equivalent to 372 (210–520) DALYs per million inhabitants.Conclusion
Dengue poses a substantial economic and disease burden in SEA with a DALY burden per million inhabitants in the region. This burden is higher than that of 17 other conditions, including Japanese encephalitis, upper respiratory infections, and hepatitis B. 相似文献93.
María Mena Alberto López-Luna Keiko Shirai Alberto Tecante Miquel Gimeno Eduardo Bárzana 《Bioprocess and biosystems engineering》2013,36(3):383-387
Hyperbranched poly-l-lactides have been synthesized by eROP in [C4MIM][PF6] media. The bis(hydroxymethyl)butyric acid molecule was used as the AB2 core co-monomer and immobilized lipase B from Candida antarctica as biocatalyst. The degree of branching could be controlled by the reaction conditions, with the maximum achieved being 0.21. The successful achievement of the hyperbranched structure is attributed to the high solvent power of substrates and products in the ionic liquid besides sustained lipase activity. 相似文献
94.
María Victoria Martín Ayelén Mariana Distefano Eduardo Julián Zabaleta Gabriela Carolina Pagnussat 《Plant signaling & behavior》2013,8(10)
Previously considered as toxic by-products of aerobic metabolism, reactive oxygen species (ROS) are emerging as essential signaling molecules in eukaryotes. Recent evidence showed that maintenance of ROS homeostasis during female gametophyte development is crucial for embryo sac patterning and fertilization. Although ROS are exclusively detected in the central cell of mature embryo sacs, the study of mutants deficient in ROS homeostasis suggests that controlled oxidative bursts might take place earlier during gametophyte development. Also, a ROS burst that depends on pollination takes place inside the embryo sac. This oxidative response might be required for pollen tube growth arrest and for sperm cell release. In this mini-review, we will focus on new insights into the role of ROS during female gametophyte development and fertilization. Special focus will be made on the mitochondrial Mn-Superoxide dismutase (MSD1), which has been recently reported to be essential for maintaining ROS homeostasis during embryo sac formation. 相似文献
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Vijayalakshmi Sridharan Preeti Tripathi Sunil Sharma Peter M. Corry Eduardo G. Moros Awantika Singh Cesar M. Compadre Martin Hauer-Jensen Marjan Boerma 《PloS one》2013,8(7)
Radiation-induced heart disease (RIHD) is a long-term side effect of radiotherapy of intrathoracic, chest wall and breast tumors when radiation fields encompass all or part of the heart. Previous studies have shown that pentoxifylline (PTX) in combination with α-tocopherol reduced manifestations of RIHD in rat models of local heart irradiation. The relative contribution of PTX and α-tocopherol to these beneficial effects are not known. This study examined the effects of PTX alone or in combination with tocotrienols, forms of vitamin E with potential potent radiation mitigation properties. Rats received localized X-irradiation of the heart with an image-guided irradiation technique. At 3 months after irradiation rats received oral treatment with vehicle, PTX, or PTX in combination with a tocotrienol-enriched formulation. At 6 months after irradiation, PTX-treated rats showed arrhythmia in 5 out of 14 animals. PTX alone or in combination with tocotrienols did not alter cardiac radiation fibrosis, left ventricular protein expression of the endothelial markers von Willebrand factor and neuregulin-1, or phosphorylation of the signal mediators Akt, Erk1/2, or PKCα. On the other hand, tocotrienols reduced cardiac numbers of mast cells and macrophages, but enhanced the expression of tissue factor. While this new rat model of localized heart irradiation does not support the use of PTX alone, the effects of tocotrienols on chronic manifestations of RIHD deserve further investigation. 相似文献
99.
Parcerisa Ivana L. Rosano Germán L. Ceccarelli Eduardo A. 《Plant molecular biology》2020,104(4-5):451-465
Plant Molecular Biology - The first biochemical characterization of a chloroplastic disaggregase is reported (Arabidopsis thaliana ClpB3). ClpB3 oligomerizes into active hexamers that resolubilize... 相似文献
100.
do Nascimento Jessica Catarine Frutuoso Beltrão Eduardo Isidoro Carneiro Rocha Cíntia Renata Costa 《Glycoconjugate journal》2020,37(2):263-275
Glycoconjugate Journal - The complex enzyme network responsible for glycan synthesis suffers significant changes during the first steps of tumor development, leading to the early formation of... 相似文献