Similar Protective Effect (similar + protective_effect)

Distribution by Scientific Domains


Selected Abstracts


Efficacy of four insect repellents against mosquito bites: a double-blind randomized placebo-controlled field study in Senegal

FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 5 2009
Bernard Uzzan
Abstract Insect-borne diseases represent a worldwide threat. In addition to fight against vectors (insecticides) and disease prevention (vaccination against yellow fever, chemoprophylaxis against malaria), insect repellents applied on the skin could help reduce the heavy burden related to these diseases. In a field study performed in Senegal, we compared the efficacy of one skin application between 3 and 4 p.m. of four spray repellents [icaridine 20%, para-menthane-diol (PMD) 20% and 50% and DEET 50%] against placebo, among 100 healthy male and female volunteers experienced with mosquito capture. Double-blind randomized cross-over placebo-controlled study (Latin-square design) during five consecutive nights (7 p.m. to midnight) in two villages was conducted. To avoid residual effect, right or left leg was alternately exposed during consecutive nights and the exposed leg was washed before next night. The statistical model was random and mixed effects anova. All four active repellents provided a significant and similar protection compared with placebo, lasting 8 h. However, there was a non-significant trend for a higher protection by DEET 50% than by PMD 20% (P = 0.07). Duration of protection was similar for all repellents. Their effects were similar among men and women, and against Anopheles or other species. No serious adverse drug reaction was noticed. Using a rigorous methodology and a large number of volunteers, our well-controlled study demonstrated an important and similar protective effect of all four repellents compared with placebo. Such field studies should be required before approval of any newly developed repellent. [source]


Prostacyclin inhibits endothelial cell XIAP ubiquitination and degradation

JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2007
Jun-Yang Liou
To understand the role of prostacyclin (PGI2) in protecting endothelial cells from apoptosis, we evaluated the effects of carbaprostacyclin (cPGI2) on H2O2 -induced human umbilical vein endothelial cell (HUVEC) apoptosis. cPGI2 suppressed H2O2 -induced annexin V-positive cells in a concentration- and time-dependent manner. Pre-treatment of HUVEC with 50 µM cPGI2 for 4 h produced the maximal anti-apoptotic effect. Authentic PGI2 generated by adenoviral transfer of PGI2 synthetic genes exerted a similar protective effect. cPGI2 inhibited Smac/DIABLO release from mitochondria, caspase 3 activation, focal adhesion protein degradation, and cell detachment. cPGI2 selectively protected X-linked inhibitor of apoptosis protein (X-linked IAP, XIAP) from H2O2 -induced ubiquitination, and preserved XIAP protein levels. PD-98059 but not H-89 abrogated the protective action of cPGI2. cPGI2 increased ERK phosphorylation which was blocked by PD-98059. HUVEC stably transfected with dominant negative Ras abrogated XIAP preservation by cPGI2 while constitutive active Ras increased ERK phosphorylation and protected XIAP from degradation. Our results demonstrate for the first time that PGI2 inhibits XIAP ubiquitination and degradation via the Ras/MEK-1/ERK signaling pathway. Preservation of XIAP proteins represents a key mechanism by which PGI2 protects endothelial cells from oxidant-induced apoptosis. J. Cell. Physiol. 212:840,848, 2007. © 2007 Wiley-Liss, Inc. [source]


Glial cell line-derived neurotrophic factor protects astrocytes from staurosporine- and ischemia- induced apoptosis

JOURNAL OF NEUROSCIENCE RESEARCH, Issue 15 2007
Albert Cheung Hoi Yu
Abstract Glial cell line-derived neurotrophic factor (GDNF) promotes the survival and functions of neurons. It has been shown to be a promising candidate in the treatment of ischemia and other neurodegenerative diseases. We transfected mouse astrocytes in primary cultures with a human GDNF gene and found that their conditioned medium could not only support the growth and survival of cultured dopaminergic neurons but also protect astrocytes from staurosporine- and ischemia-induced apoptosis. This indicated that these transfected astrocytes could release GDNF. A similar protective effect on astrocytes against apoptosis was evident when recombinant human GDNF was used. Moreover, GDNF reduced caspase-3 activity but not that of caspase-1 in cultured astrocytes after ischemia treatment. Thus, GDNF protects astrocytes from apoptosis by inhibiting the activation of caspase-3. © 2007 Wiley-Liss, Inc. [source]


Bronchodilatory effects of the aqueous extract of Gynostemma pentaphyllum and gypenosides III and VIII in anaesthetized guinea-pigs

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2005
Clara Circosta
The bronchodilatory activity of the aqueous extract of Gynostemma pentaphyllum Makino leaves was investigated in anaesthetized guinea-pigs and compared with two of its isolated gypenosides (III and VIII). The results showed that the intravenous administration of the decoction of G. pentaphyllum (2.5, 5 or 10 mg kg,1) decreased bronchial resistance in basal conditions and significantly (P<0.01) reduced (68% inhibition) the bronchoconstrictor action of histamine. Furthermore, the extract antagonized (80% inhibition) the bronchoconstrictor response induced by the antigen in sensitized guinea-pigs. Gypenosides III (0.7 mg kg,1, i.v.) and VIII (0.3 mg kg,1, i.v.) caused a similar protective effect in both experimental models used; however, the duration and the intensity of the action was less than that of the extract containing corresponding quantities of gypenosides III and VIII. This study confirmed the validity of the traditional use of this plant in the treatment of asthma and other respiratory disorders. [source]