12,265 research outputs found

    Extraction and isolation of PCR amplifiable genomic DNA from Camellia sinensis (L.) Kuntze

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    Extraction and isolation of high quality DNA suitable for downstream molecular techniques in plants with high polyphenolic contents are almost impossible due to inhibitors of polymerase chain reactions. In this study DNA from Camellia sinensis (L.) Kuntze leaf tissue was successfully extracted and isolated by optimization of extraction parameters. This resulted in a high yield of DNA of up to 125 μg ml -1 from 0.3 g of leaf tissue. The yield of DNA extracted decreased from 125 to 92 μg ml -1 at 200/800/100 μl (EBA/EBB/SDS) extraction buffer combinations and similarly at all buffer combinations with increase in incubation temperature from 50 to 60°C. Carbohydrate and protein contamination derived from optical density ratios of 230/260 and 260/280 were 0-1.68 and 0-1.14, respectively. The optimal extraction parameters were as follows: precipitation time 40 min at 50°C incubation temperature and 200/800/100 μl (EBA/EBB/SDS) extraction buffer combinations. The DNA obtained is of high integrity, which has produced excellent results when used as template for PCR

    Drv Concentrations And Viral Load In Csf In Patients On Drv/r 600/100 Or 800/100mg Once Daily Plus Two Nrti

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    Introduction Darunavir/r (DRV/r) is currently used at a dose of 800/100 mg once daily (OD) in a high proportion of patients. Pharmacokinetic data suggest that 600/100 OD may be effective, reducing toxicity and cost. However, drug concentrations in reservoirs such as cerebrospinal fluid (CSF) might not be adequate to inhibit viral replication. We aimed to evaluate concentrations of DRV and HIV‐1 viral load (VL) in CSF patients receiving DRV 600/100 mg OD. Methods DRV600 is an ongoing randomized open study comparing DRV/r 800/100 mg (DRV800) vs 600/100 mg (DRV600) OD plus TDF/FTC or ABC/3TC in 100 virologically suppressed patients (eudraCT 2011‐006272‐39). Here we present the results of a CSF sub‐study. A lumbar puncture (LP) was performed in participating patients after at least six months of inclusion in the study, 20–28 hours after a dose of DRV/r. VL (PCR, LOD 40 copies/mL) was determined in CSF and in plasma. DRV concentrations were quantified in CSF by liquid chromatography mass spectrometry (LC/MS/MS) and in plasma using high‐performance liquid chromatography (HPLC). Results Sixteen patients were included (eight in each arm). All DRV600 patients and four out of eight DRV800 patients received TDF/FTC, and the other four ABC/3TC. 75% were males, median (range) age was 48 (17–71) years, CD4 cell count 532 cells/mL (190–1,394). Median total time on DRV/r was 30 (11–57) months, and since the beginning of the study 8 (6–12) months in DRV800 and 10 (7–12) months in DRV600 patients. LP was performed a median of 26 (24–28) hours after the last DRV/r+TVD or KVX dose. In DRV600 patients the median DRV plasma levels were 1,674 (326–3,742) ng/mL, CSF levels 17.08 (5.79–30.19) ng/mL and DRV CSF:plasma ratio 0.0084 (0.0028–0.0388), while in the DRV800 arm, median DRV plasma levels were 1,707 (958–3,910) ng/mL, CSF levels 13.23 (3.47–32.98) ng/mL and DRV CSF:plasma ratio 0.0104 (0.0018–0.0262). All patients had VL<40 copies/mL in plasma and 14 patients VL<40 copies/mL in CSF. Two patients (1 in each arm, and taking TDF/FTC) had detectable VL in CSF (280 and 159 c/mL). These patients had the lowest CSF DRV concentrations (5.47 and 3.47 ng/mL), with plasma DRV concentrations of 802 and 958 ng/mL respectively. Conclusions CSF DRV concentrations and CSF VL were similar between patients receiving DRV/r 800/100 mg or 600/100 mg OD. Low CSF DRV concentrations might be associated with viral escape in CNS. This may be taken into account in patients receiving OD DRV/r. Larger studies should confirm these findings

    Speckle Interferometry of Metal-Poor Stars in the Solar Neighborhood. I

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    We report the results of speckle-interferometric observations of 109 high proper-motion metal-poor stars made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. We resolve eight objects -- G102-20, G191-55, BD+19^\circ~1185A, G89-14, G87-45, G87-47, G111-38, and G114-25 -- into individual components and we are the first to astrometrically resolve seven of these stars. New resolved systems included two triple (G111-38, G87-47) and one quadruple (G89-14) star. The ratio of single-to-binary-to-triple-to-quadruple systems among the stars of our sample is equal to 71:28:6:1.Comment: 8 pages, 4 figures, accepted to Astrophysical Bulleti

    Complex Networks on a Rock Joint

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    A complex network approach on a rough fracture is developed. In this manner, some hidden metric spaces (similarity measurements) between apertures profiles are set up and a general evolutionary network in two directions (in parallel and perpendicular to the shear direction) is constructed. Also, an algorithm (COmplex Networks on Apertures: CONA) is proposed in which evolving of a network is accomplished using preferential detachments and attachments of edges (based on a competition and game manner) while the number of nodes is fixed. Also, evolving of clustering coefficients and number of edges display similar patterns as well as are appeared in shear stress, hydraulic conductivity and dilation changes, which can be engaged to estimate shear strength distribution of asperities.Comment: ROCKENG09: Proceedings of the 3rd CANUS Rock Mechanics Symposium, Toronto, May 2009 (Ed: M.Diederichs and G. Grasselli
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