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1.
A comparative performance evaluation of DNA extraction methods from anti-diabetic botanical supplements using various commercial kits was conducted, to determine which produces the best quality DNA suitable for PCR amplification, sequencing and species identification. All plant materials involved were of suboptimal quality showing various levels of degradation and therefore representing real conditions for testing herbal supplements. Eight different DNA extraction methods were used to isolate genomic DNA from 13 medicinal plant products. Two methods for evaluation, DNA concentration measurements that included absorbance ratios as well as PCR amplifiability, were used to determine quantity and quality of extracted DNA. We found that neither DNA concentrations nor commonly used UV absorbance ratio measurements at A 260/A 280 between 1.7 and 1.9 are suitable for globally predicting PCR success in these plant samples, and that PCR amplifiablity itself was the best indicator of extracted product quality. However, our results suggest that A 260/A 280 ratios below about 1.3 and above 2.3 indicated a DNA quality too poor to amplify. Therefore, A 260/A 280 measurements are not useful to identify samples that likely will amplify but can be used to exclude samples that likely will not amplify reducing the cost for unnecessarily subjecting samples to PCR. The two Nucleospin® plant II kit extraction methods produced the most pure and amplifiable genomic DNA extracts. Our results suggest that there are clear, discernable differences between extraction methods for low quality plant samples in terms of producing contamination-free, high-quality genomic DNA to be used for further analysis.  相似文献   
2.

Purpose

Trabecular meshwork (TM) bypass surgeries attempt to enhance aqueous humor outflow (AHO) to lower intraocular pressure (IOP). While TM bypass results are promising, inconsistent success is seen. One hypothesis for this variability rests upon segmental (non-360 degrees uniform) AHO. We describe aqueous angiography as a real-time and physiologic AHO imaging technique in model eyes as a way to simulate live AHO imaging.

Methods

Pig (n = 46) and human (n = 6) enucleated eyes were obtained, orientated based upon inferior oblique insertion, and pre-perfused with balanced salt solution via a Lewicky AC maintainer through a 1mm side-port. Fluorescein (2.5%) was introduced intracamerally at 10 or 30 mm Hg. With an angiographer, infrared and fluorescent (486 nm) images were acquired. Image processing allowed for collection of pixel information based on intensity or location for statistical analyses. Concurrent OCT was performed, and fixable fluorescent dextrans were introduced into the eye for histological analysis of angiographically active areas.

Results

Aqueous angiography yielded high quality images with segmental patterns (p<0.0001; Kruskal-Wallis test). No single quadrant was consistently identified as the primary quadrant of angiographic signal (p = 0.06–0.86; Kruskal-Wallis test). Regions of high proximal signal did not necessarily correlate with regions of high distal signal. Angiographically positive but not negative areas demonstrated intrascleral lumens on OCT images. Aqueous angiography with fluorescent dextrans led to their trapping in AHO pathways.

Conclusions

Aqueous angiography is a real-time and physiologic AHO imaging technique in model eyes.  相似文献   
3.
High-yielding dwarf clones of Hevea brasiliensis are tolerant to wind damage and therefore useful for high-density planting. The identification of molecular markers for the dwarf character is very important for isolating true-to-type high-yielding dwarf hybrid lines in the early stage of plant breeding programs. We have identified a dwarf genome-specific random amplified polymorphic DNA (RAPD) marker in rubber tree. A total of 115 random oligonucleotide 10-mer primers were used to amplify genomic DNA by PCR, of which 19 primers produced clear and detectable bands. The primer OPB-12 generated a 1.4-kb DNA marker from both natural and controlled F1 hybrid progenies (dwarf stature) derived from a cross between a dwarf parent and a normal cultivated clone as well as from the dwarf parent; it was absent in other parent (RRII 118). To validate this DNA marker, we analyzed 22 F1 hybrids (13 with a dwarf stature and nine with a normal stature); the dwarf genome-specific 1.4-kb RAPD marker was present in all dwarf-stature hybrids and absent in all normal-stature hybrids. This DNA marker was cloned and characterized. DNA marker locus specificity was further confirmed by Southern blot hybridization. Our results indicate that Southern blot hybridization of RAPD using probes made from cloned DNA fragments allows a more accurate analysis of the RAPD pattern based on the presence/absence of specific DNA markers than dye-stained gels or Southern blot analysis of RAPD blots using probes made from purified PCR products. Detection of RAPD markers in the hybrid progenies indicates that RAPD is a powerful tool for identifying inherited genome segments following different hybridization methods in perennial tree crops.  相似文献   
4.
5.
alpha-Galactosidase was strongly induced in the white-rot fungus Pleurotus florida by arabinose than its natural substrates and was purified to homogeneity by acetone precipitation, ultrafiltration and DEAE-Sepharose chromatography. The enzyme was a monomeric protein with a molecular mass of approximately equal to 99 kDa, as revealed by native-PAGE and SDS-PAGE. alpha-Galactosidase was optimally active at 55 degrees C for the hydrolysis of p-nitrophenyl-alpha-galactopyranoside (PNPalphaG) and lost its 20% and 50% of original activity in 30 min at 60 degres C and 70 degrees C, respectively. The pH optimum of the enzyme was between 4.6 and 5.0. It was stable in a wide pH range (pH 4.0 to 9.0) at 55 degrees C for 2 h. The Ag+ and Hg2+ strongly inhibited the enzyme activity. Galactose, glucose, maltose and lactose also inhibited the enzyme activity, whereas N-bromosuccinimide treatment resulted in near total loss of acitivity. The Km and Vmax values of the enzyme for PNPalphaG were found to be 1.1 mM, and 77 micromol min(-1) mg(-1), respectively. alpha-Galactosidase immobilized in agar was more effective for the degradation of raffinose than in the sodium alginate. TLC results indicated its potential for the removal of raffinose and stachyose in soymilk.  相似文献   
6.
Statins activate phosphatidylinositol-3-kinase, which activates ecto-5'-nucleotidase and phosphorylates 3-phosphoinositide-dependent kinase-1 (PDK-1). Phosphorylated (P-)PDK-1 phosphorylates Akt, which phosphorylates endothelial nitric oxide synthase (eNOS). We asked if the blockade of adenosine receptors (A(1), A(2A), A(2B), or A(3) receptors) could attenuate the induction of Akt and eNOS by atorvastatin (ATV) and whether ERK1/2 is involved in the ATV regulation of Akt and eNOS. In protocol 1, mice received intraperitoneal ATV, theophylline (TH), ATV + TH, or vehicle. In protocol 2, mice received intraperitoneal injections of ATV, U0126 (an ERK1/2 inhibitor), ATV + U0126, or vehicle; 8 h later, hearts were assessed by immunoblot analysis. In protocol 3, mice received intraperitoneal ATV alone or with 8-sulfophenyltheophylline (SPT); 1, 3, and 6 h after injection, hearts were assessed by immunoblot analysis. In protocol 4, mice received intraperitoneal ATV alone or with SPT, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX), 1,3,7-trimethyl-8-(3-chlorostyryl)xanthine (CSC), alloxazine, or MRS-1523; 3 h after injection, hearts were assessed by immunoblot analysis. ATV increased P-ERK, P-PDK-1, Ser(473) P-Akt, Thr(308) P-Akt, and P-eNOS levels. TH blocked ATV-induced increases in P-ERK, Ser(473) P-Akt, Thr(308) P-Akt, and P-eNOS levels without affecting the induction of P-PDK-1 by ATV. U0126 blocked the ATV induction of Ser(473) P-Akt and Thr(308) P-Akt while attenuating the induction of P-eNOS. A detectable increase in P-ERK, Ser(473) P-Akt and P-eNOS was seen 3 and 6 h after injection but not at 1 h. DPCPX, CSC, and alloxazine partially blocked the ATV induction of P-ERK, Ser(473) P-Akt, and P-eNOS. In conclusion, blockade of adenosine A(1), A(2A), and A(2B) receptors but not A(3) receptors inhibited the induction of Akt and eNOS by statins. Adenosine was required for ERK1/2 activation by statins, which resulted in Akt and eNOS phosphorylation.  相似文献   
7.
Haptoglobin (HP) is a serum protein that has the capability of binding the extracorpuscular haemoglobin released during haemolysis. It plays an important role in protection of haemolytic disease by reducing the oxidative and peroxidative potential at free haemoglobin. The present study was aimed to determine the prevalence of HP polymorphism among different Indian populations, anthropologically belonging to diverse ethnicity. The polymorphism was screened among 642 unrelated individuals belonging to 14 population groups of India including both tribal and non-tribal caste groups from different geographical regions of India with distinct linguistic affiliations. An attempt is also made to understand the distribution of HP polymorphism among the studied populations. The result reveals the HP gene to be polymorphic in all the studied populations. Except the two tribal populations (Thotis of Andhra Pradesh and Patelias of Rajasthan) and one caste population (Rajput of Himachal Pradesh), all the studied populations are found to obey the Hardy-Weinberg equilibrium. The significance of the present study is elucidated with the prevalence of high mutant HP*2 allele frequency in India. Selection could be one of the most plausible explanations for this high HP frequency because of its uniformly high occurrence among all the studied populations.  相似文献   
8.
Sempervirenic acid, a new diterpene has been isolated from Solidago sempervirens and its structure determined by spectroscopic methods and chemical conversions to be 3β-acetoxy-labda-7,13-diene-15-oic acid.  相似文献   
9.
Studies have investigated the association between angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and cardiometabolic risk factors (CMRFs), however with varying results, which could be due to ethnicity differences. Therefore, the present study was conducted among Bhil tribal population (a mendelian population with the common gene pool and same sociocultural attributes), residing in two different environmental settings. The study attempts to understand the distribution and extent of association of ACE I/D gene polymorphism with cardiometabolic risk factors among Bhils from rural and urban settings. All the obesity and blood pressure variables were collected form 432 recruited subjects from both sexes aged 25–65 years and ACE I/D polymorphism was analysed on 299 subjects. Almost all the studied CMRFs were found to be significantly higher among urban Bhils. ACE gene was found to be polymorphic in the studied groups. DD genotype was found to pose more than threefold significant risk for low HDLC only in rural area. Estimate change analysis revealed an increasing D allele dose leads to more than one unit increase in Blood Pressure, and more than three units decrease in HDLC. The study highlights the differential effect of ACE I/D gene polymorphism in different environmental settings.  相似文献   
10.
Invasion by the malaria merozoite depends on recognition of specific erythrocyte surface receptors by parasite ligands. Plasmodium falciparum uses multiple ligands, including at least two gene families, reticulocyte binding protein homologues (RBLs) and erythrocyte binding proteins/ligands (EBLs). The combination of different RBLs and EBLs expressed in a merozoite defines the invasion pathway utilized and could also play a role in parasite virulence. The binding regions of EBLs lie in a conserved cysteine-rich domain while the binding domain of RBL is still not well characterized. Here, we identify the erythrocyte binding region of the P. falciparum reticulocyte binding protein homologue 1 (PfRH1) and show that antibodies raised against the functional binding region efficiently inhibit invasion. In addition, we directly demonstrate that changes in the expression of RBLs can constitute an immune evasion mechanism of the malaria merozoite.  相似文献   
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