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This study established a constant-temperature fluorescence quantitative detection method, combining loop-mediated isothermal amplification (LAMP) with molecular beacons. The advantages of LAMP are its convenience and efficiency, as it does not require a thermocycler and results are easily visualized by the naked eye. However, a major disadvantage of current LAMP techniques is the use of indirect evaluation methods (e.g., electrophoresis, SYBR Green I dye, precipitation, hydroxynaphthol blue dye, the turbidimetric method, calcein/Mn2+ dye, and the composite probe method), which cannot distinguish between the desired products and products of nonspecific amplification, thereby leading to false positives. Use of molecular beacons avoids this problem because molecular beacons produce fluorescence signals only when binding to target DNA, thus acting as a direct indicator of amplification products. Our analyses determined the optimal conditions for molecular beacons as an evaluation tool in LAMP: beacon length of 25–45 bp, beacon concentration of 0.6–1 pmol/μL, and reaction temperature of 60–65 °C. In conclusion, we validated a novel molecular beacon loop-mediated isothermal amplification method (MB-LAMP), realizing the direct detection of LAMP product.

The Artemisia/Chenopodiaceae (A/C) ratio is assumed to be a useful index for reconstructing moisture changes in arid and semi-arid regions. Thorough modern pollen studies are still lacking to understand the reliability and limitation of A/C ratio as a moisture indicator, however. Here we review how well this ratio can be applied in arid and semi-arid China on the basis of new surface pollen data, previous data synthesis and other publications. Results indicate that variance in the A/C ratio can permit identification of modern vegetation types and that the A/C ratio generally has a positive relationship with annual precipitation. However, soil salinity, vegetation community composition, human activity and sample provenance (e.g. soil and lake sediments) will affect the values of the A/C ratio in different vegetation zones and therefore the A/C ratio is not comparable in different regions. We argue that the A/C ratio can only be used to reconstruct vegetation types and climate change in regions with precipitation <450–500 mm, and in steppe, steppe desert and desert areas. Careful studies should be undertaken to understand the modern pollen–vegetation–climate relationships in various regions before using the A/C ratio to interpret vegetation and climate.

Background and Purpose-ANRIL encodes a long antisense noncoding RNA in the INK4 locus. Although ANRIL has been proven to be associated with coronary heart disease, its roles in stroke are inconsistent, and sparse data are available regarding hemorrhagic stroke. Methods-A Chinese case-control study was conducted, comprising 1657 cases (724 atherothrombosis, 466 lacunar infarction, and 462 hemorrhagic strokes) and 1664 controls. Stroke patients were prospectively followed-up for a median of 4.5 (range, 0.1-6.0) years. Expression of ANRIL transcripts was examined in 42 human atherosclerotic plaques. Results-After adjustment for vascular risk factors and correction for multiple comparisons, subjects carrying the GG genotype of rs10757278 had 1.47-fold (95% CI, 1.11-1.89; Pϭ0.05) and 1.60-fold (95% CI, 1.16 -2.15; Pϭ0.04) increased risk for atherothrombotic and hemorrhagic strokes, respectively. During the follow-up, 317 recurrent strokes and 301 deaths from all causes were documented. Subjects carrying rs10757278GG had higher risk for stroke recurrence (relative risk [RR],1.56; 95% CI,1.15-2.12; Pϭ0.005) and cardiovascular mortality (RR, 2.0; 95% CI, 1.26 -3.18; Pϭ0.003), respectively. Rs10757274 was also associated with stroke risk and recurrence. Family history of stroke further increased the stroke risk by 2.37-fold (95% CI, 1.38 -4.06; Pϭ0.01) and recurrent stroke risk by 2.45-fold (95% CI, 1.56 -3.86; PϽ0.0001) respectively, when compared with those carrying none of G-alleles and without family history. Finally, rs10757278 was associated with differential expression of the ANRIL transcripts. Conclusions-Our findings indicated that the ANRIL may serve as a novel genetic marker for the risk of atherothrombotic and hemorrhagic stroke and their recurrence. (Stroke. 2012;43:14-21.)Key Words: chromosome 9p21.3 Ⅲ follow-up studies Ⅲ genetics Ⅲ risk factors S troke is a major cause of death and disability worldwide and in China. Survivors are often disabled, require long-term care, and are at high risk of recurrence. Among subtypes of stroke, hemorrhagic stroke accounts for 20% to 40% in the Chinese population; in contrast, the majority (80 -90%) of strokes are cerebral infarctions in most western populations. 1 The reasons for high risk of stroke, especially hemorrhagic stroke, among the Chinese, remain unknown. The contribution of genetic risk to stroke is still not completely understood.It is generally accepted that genetic variants on chromosome 9p21.3 are associated with the risk of coronary artery disease, 2-4 but its roles in stroke are inconsistent. [5][6][7][8][9][10][11][12] A recent meta-analysis 13 showed that the association of 9p21.3 with stroke is only confined to the subtype of large-vessel strokes. However, a recent genome-wide association study showed that the 9p21.3 region is also implicated in risk for intracranial aneurysm, in which atherosclerosis is not thought to play a major role. 14 Therefore, additional studies are needed to determine the mechanisms by which the 9p21.3 region affects vascular...

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Eight randomly selected pharmaceuticals, which included ibuprofen, ketoprofen, albuterol, acebutolol, propafenone, betaxolol, methylphenidate, and homatropine, were directly separated on a cellulose tris(4-methylbenzoate) chiral stationary phase (CSP) without derivatization via normal phase mode HPLC. Enantioresolution was achieved by the optimization of the type and the ratio of mobile phase modifiers and additives. The modifiers included alcohols; the mobile phase additives were trifluoroacetic acid (TFA) and triethylamine (TEA). It was found that methanol and ethanol were superior to isopropanol as mobile phase modifiers for enhancing chiral separation of some of the chiral drugs. The results also demonstrated that TFA has a dominant effect on chiral separations for both acidic and basic chiral drugs, although for some basic drug such as homatropine, TEA was more beneficial at improving enantioseparation. The separation of acebutolol enantiomers was achieved for the f i s t time by adding both TFA and TEA to the mobile phase. The purpose of this paper is to demonstrate that the applicability of cellulose based CSPs can be expanded by controlling the mobile phase compositions through the addition of trace amounts of achiral additives and the selection of the appropriate alcoholic modifier. o 1996 Wiley-Liss, Inc.KEY WORDS: enantioseparations, high-perfonnance liquid chromatography, mobile phase modifier and additive, cellulose-based CSP, chiral acidic and basic drugs To meet the growth of the stereoseparation technologies, there has been a remarkable development in the number of chiral stationary phases (CSPs) for use in HPLC during the last decade.' Although many attempts have been made to rationalize stereogenic separation mechanisms for each type of CSP, often times there are difficulties in determining how to select an appropriate CSP to resolve a particular stereoseparation problem from the many CSPs available. Armstrong et al.' developed a multimodal derivatized cyclodextrin CSP on which chiral separations for different categories of chiral compounds can be achieved through alteration of the mobile phase mode. As a result, the cost of the enantiomeric separations can be effectively reduced.Cellulose-based CSPs are among the most widely used stationary phases for enantiomeric separations. Two groups of Japanese scientists initialized a series of investigations almost at the same time about 10 years ago in which ester and carbamate derivatives of cellulose were synthesized and subsequently coated on a pretreated silica gel matrix.= This type of chiral stationary phase is now commercially available and essentially used in normal phase mode for broad stereoseparation A discussion of chiral separations on cellulose-based CSPs was given by Shibata et al.17 In this review, mixtures of hexane and isopropanol were used as mobile phase compositions for almost all applications. Sometimes, an organic acid or organic base was used as an additive in the mobile phase to improve enantioseparations for chiral 0 1...