Evaluation of Antibacterial Activity and Phytoconstituents of the Aqueous Leaves Extract of Alchornea Cordifolia

Alchornea cordifolia Schum and Thonn. (Euphorbiaceae) is a plant widely used in traditional medicines of Ghana for the treatment of skin and other infections. This study evaluated the antibacterial properties and phytoconstituents of the aqueous leaves extract of A. cordifolia with particular reference to methicillin-resistant Staphylococcus aureus (MRSA). Minimum inhibitory and bactericidal concentrations (MIC and MBC) of the aqueous leaves extract of the plant were evaluated against 32 clinical isolates of MRSA and controls by the microdilution technique in Iso-sensitest broth. Growth and time-kill curves were also carried out using spectroscopy at 490 nm and viable cell counts method. Mean diameter of zones of inhibition ranged 18-30 mm of the aqueous extract of the plant were found against MRSA. MIC and MBC values ranged 1.6-3.1 mg/ml and 6.5-12.5 mg/ml of the aqueous leaves extract of A. cordifolia were found against the 32 clinical isolates of MRSA with most of the strains having MIC value of 3.1 mg/ml and MBC value of 12.5 mg/ml. Growth and time-kill curves indicate bacteriostatic activity of the plant extract on MRSA. Phytochemical analysis of the extract showed low concentrations of alkaloids and saponins but very high concentrations of tannins present in the leaves of the plant. From the results of the study, aqueous leaves extract of A. cordifolia may contain antibacterial compounds that justify its usage in traditional medicine

Allele-specific PCR

Allele-specific PCR for two kdr mutations. The two numbers under the 1534 and 1016 columns indicate the two alleles: For 1534, 83 is the melting point for the resistant allele and 79 is susceptible; for 1016, 83 is susceptible and 79 is resistant

Data from: Restoration of pyrethroid susceptibility in a highly resistant Aedes aegypti population

Insecticide resistance has evolved in disease vectors worldwide, creating the urgent need to either develop new control methods or restore insecticide susceptibility to regain the use of existing tools. Here we show that phenotypic susceptibility can be restored in a highly resistant field-derived strain of Aedes aegypti in only ten generations through rearing them in the absence of insecticide

Inhibition of CaMKII Phosphorylation of RyR2 Prevents Induction of Atrial Fibrillation in FKBP12.6 Knockout Mice

RATIONALE: Abnormal calcium release from sarcoplasmic reticulum (SR) is considered an important trigger of atrial fibrillation (AF). Whereas increased CaMKII activity has been proposed to contribute to SR leak and AF-induction, downstream targets of CaMKII remain controversial. OBJECTIVE: To test the hypothesis that inhibition of CaMKII-phosphorylated type-2 ryanodine receptors (RyR2) prevents AF initiation in FKBP12.6-deficient (−/−) mice. METHODS AND RESULTS: Mice lacking RyR2-stabilizing subunit FKBP12.6 had a higher incidence of spontaneous and pacing-induced AF compared to wildtype mice. Atrial myocytes from FKBP12.6−/− mice exhibited spontaneous Ca(2+) waves (SCaWs) leading to Na(+)/Ca(2+)-exchanger (NCX) activation and delayed afterdepolarizations (DADs). Mutation S2814A in RyR2, which inhibits CaMKII phosphorylation, reduced Ca(2+) spark frequency, SR Ca(2+) leak and DADs in atrial myocytes from FKBP12.6−/−:S2814A mice compared with FKBP12.6−/− mice. Moreover, FKBP12.6−/−:S2814A mice exhibited a reduced susceptibility to inducible AF, whereas FKBP12.6−/−:S2808A mice were not protected from AF. CONCLUSIONS: FKBP12.6 mice exhibit AF caused by SR Ca(2+) leak, NCX activation and DADs, which promote triggered activity. Genetic inhibition of RyR2-S2814 phosphorylation prevents AF induction in FKBP12.6−/− mice by suppressing SR Ca(2+) leak and DADs. These results suggest that suppression of RyR2-S2814 phosphorylation as a potential anti-AF therapeutic target

CDC bottle bioassay data

Data from CDC bottle bioassays at F10 using both permethrin and deltamethrin. Time is in minutes. KD = "knock-down.