Diversity of Saccharomyces boulardii CNCM I-745 mechanisms of action against intestinal infections

The yeast Saccharomyces boulardii CNCM I-745 is one of the probiotics recommended for the prevention of antibiotic-associated diarrhea. Studies conducted in vivo and in vitro demonstrated that in the case of infectious diseases there are two potential sites of action of Saccharomyces boulardii CNCM I-745:(1)An action on enteropathogenic microorganisms(adhesion of bacteria and their elimination or an effect on their virulence factors: Toxins, lipopolysaccharide,etc.); and(2) a direct action on the intestinal mucosa(trophic effects, effects on epithelial reconstitution, anti-secretory effects, anti-inflammatory,immunomodulators). Oral administration of Saccharomyces boulardii CNCM I-745 to healthy subjects does not alter their microbiota. However, in the case of diseases associated with the use of antibiotics or chronic diarrhea, Saccharomyces boulardii CNCM I-745 can restore the intestinal microbiota faster. The interaction of Saccharomyces boulardii CNCM I-745 with the innate immune system have been recently demonstrated thus opening up a new therapeutic potential of this yeast in the case of diseases associated with intestinal infections but also other pathologies associated with dysbiosis such as inflammatory diseases.

Fifteen years of preclinical and clinical experiences about biotherapy treatment of lesions induced by accidental irradiation and radiotherapy

High dose radiation exposures involving medical treatments or accidental irradiation may lead to extended damage to the irradiated tissue. Alleviation or even eradication of irradiation induced adverse events is therefore crucial. Because developments in cell therapy have brought some hope for the treatment of tissues damages induced by irradiation, the Institute for Radiation and Nuclear Safety contributed to establish the clinical guidelines for the management of accidentally irradiated victims and to provide the best supportive care to patients all over the world. In the past 15 years, we contributed to develop and test cell therapy for protection against radiation side effects in several animalmodels, and we proposed mechanisms to explain the benefit brought by this new therapeutic approach. We established the proof of concept that mesenchymal stem cells (MSCs) migrate to damaged tissues in the nonobese diabetic/severe combined immunodeficiency immunotolerant mice model and in non-human primate after radiation exposure. We showed that the intravenous injection of MSCs sustains hematopoiesis after total body irradiation, improves wound healing after radiodermatitis and protects gut function from irradiation damages. Thanks to a tight collaboration with clinicians from several French hospitals, we report successful treatments of therapeutic/accidental radiation damages in several victims with MSC infusions for hematopoiesis correction, radio-induced burns, gastrointestinal disorders and protection homeostatic functions of gut management after radio-therapy.

New insights for pelvic radiation disease treatment:Multipotent stromal cell is a promise mainstay treatment for the restoration of abdominopelvic severe chronic damages induced by radiotherapy

Radiotherapy may induce irreversible damage on healthy tissues surrounding the tumor. It has been reported that the majority of patients receiving pelvic radiation therapy show early or late tissue reactions of graded severity as radiotherapy affects not only the targeted tumor cells but also the surrounding healthy tissues. The late adverse effects of pelvic radiotherapy concern 5% to 10% of them, which could be life threatening. However, a clear medical consensus concerning the clinical management of such healthy tissue sequelae does not exist. Although no pharmacologic interventions have yet been proven to efficiently mitigate radiotherapy severe side effects, few preclinical researches show the potential of combined and sequential pharmacological treatments to prevent the onset of tissue damage. Our group has demonstrated in preclinical animal models that systemic mesenchymal stromal cell(MSC) injection is a promising approach for the medical management of gastrointestinal disorder after irradiation. We have shown that MSCs migrate to damaged tissues and restore gut functions after irradiation.We carefully studied side effects of stem cell injection for further application in patients. We have shown that clinical status of four patients suffering from severe pelvic side effects resulting from an over-dosage was improved following MSC injection in a compationnal situation.

水稻种植区疟疾媒介环境生产力与地面植被覆盖的关系(英文)

本文选择了肯尼亚Mwea水稻种植区中Kangichiri、Kiuria和Rurumi3个村庄-农田交错地区为观察区,分析并比较了2种卫星数据对水稻种植区疟疾媒介分布的指示情况。首先运用2005年7月获取的Quickbird(分辨率0.6m)和Ikonos(分辨率4m)卫星数据在ErdasImagineV8.7中生成观察区的地面植被覆盖图;并于2005年的7月至2006的7月观察相应地区地面蚊虫消长情况。通过对观察区的卫星数据的最大似然法监测分类,并于分类后对每一田块与灌溉渠道都用Arc Info9.1进行栅格矢量化处理(每一栅格设置唯一的标识)。所有调查的蚊虫滋生点,依照水稻的生育期的不同分为6层进行分析。然后将经差分GPS定位的每一处水稻田及按蚊产卵点都叠加到该地区的卫星底层数据上,并对不同的水体、水稻生育期、调查地点的蚊虫滋生情况进行了方差分析。结果显示,由于Ikonos只有可见光和近红外光谱分辨能力,单一的Ikonos卫星数据难以区分不同样点和分层的生境,而QuickBird具有全光谱分辨能力,可区分所有的稻田生境。因此,可根据QuickBird0.6m卫星数据的土地利用和覆盖指数和阿拉伯按蚊滋生点幼虫的增殖特性,在当地建立和应用媒介综合防治系统(IVM-Integrated Vector Management)。