Molecular cloning and characterization of a platelet glycoprotein Ib-binding protein from the venom of Trimeresurus stejnegeri

A platelet glycoprotein Ib-binding protein, termed TSV-GPIb-BP, was isolated from the venom of Trimeresurus stejnegeri. On SDS-polyacrylamide gel electrophoresis, TSV-GPIb-BP showed a single band with an apparent molecular weight of 28,000 and two distinct bands with apparent molecular weights of 16,000 and 15,000 under non-reducing and reducing conditions, respectively. cDNA clones containing the coding sequences for both TSV-GPIb-BP subunits were isolated and sequenced. The deduced amino acid sequences of TSV-GPIb-BP subunits were confirmed by N-terminal protein sequencing and trypsin-digested peptide mass fingerprinting. Interestingly, the a subunit of TSV-GPIb-BP is identical to that of alboaggregin-B, and the sequence identity of their beta subunits is 94.3%. TSV-GPIb-BP inhibited ristocetin-induced human platelet agglutination in platelet-rich plasma under lower dosages (<5 mug/ml). On the other hand, it directly aggregated washed human platelets in the absence of additional Ca2+ or any other cofactors under higher dosages (>5 mug/ml). This platelet aggregation activity was dose-dependently inhibited by specific GPIbalpha antibodies, but not by those antibodies against platelet GPIa, GPIIa, GPIIb and GPIIIa. (C) 2003 Elsevier Science Ltd. All rights reserved.

Evidence of gene conversion in the evolutionary process of the codon 41/42 (-CTTT) mutation causing beta-thalassemia in southern China

The 4-bp deletion (-CTTT) at codon 41/42 (CD41/42) of the human beta-globin gene represents one of the most common beta-thalassemia mutations in East Asia and Southeast Asia, which is historically afflicted with endemic malaria, thus hypothetically evolvi

Survey of exist specifications morphometric, meristic and inter species molecular genetic on Bream (Abramis brava orientalis) in Anzali wetland, southern coast of Caspian Sea, Aras Dam Lake and Azerbijan Republic

Bream (Abramis brava orientalis) is one of Cyprindae the Caspian Sea and its basin which has a special ecological, biological and economical role. Stock of this fish in the Caspian Sea has reduced during several years for different reason the over fishing, different industrial, agriculture, urban pollution and destroy of the spawning habitat. So that fishery company decided to recover the stock of this fish by the way of artificial reproduction of a Bream couple hunted from south coast of the Caspian Sea (Iran) and setting the fingerling to the rivers and inflow wetlands of the Caspian Sea.This activity has due to 20 tons Bream annual fishing in the Iranian South coast of the Caspian Sea (Gilan province coast and Anzali wetland), The artificial reproduction has decreased Bream population diversity of Caspian sea and Anzali wetland.So it has been declined to improve Braem population diversity by the entrance of Azerbijan republic Bream and encounter to the Caspian sea Bream. Meanwhile there is Bream in the Aras Dam Lake which had been forgotten by the Fishery Company of Iran .For this reason specifications morphometric, meristic and inter species Molecular Genetic have been surveyed in Anzali wetland,Southern coast of Caspian Sea ,Aras Darn Lake and Azerbijan republic during 2003-2005. According to the research on specifications of Morphometric and Meristic of Anzali wetland(120 species),Southern coast of Caspian Sea(90 species), Aras Dam Lake(110 species) and Azerbijan Republic(125 species)has Morphometric and Meristic differences. So that average weight and total length of Anzali wetland Bream respectively was 167 g and 23/76 cm, 102 g and 27/62 cm in Caspian Sea , 461 g and 3 5/38 cm in Aras Darn Lake and 3 4189 g and 15/21 cm in Azerbijan republic (We forced to use 1 year Bream of artificial reproduction in Iran). Also variation coefficient average Morphometric, Morphometric specification Ration and meristic in Anzali wetland Bream was 17/45, 21/56 and 4/63, in Caspian Sea bream 22/58, 15/27 and 3124, in Aras Dam lake Lake 17145. 1.5/27 and 3/57 and Azerbaijan republic Bream 22/29, 19/66 and 4/22. Also Bream of these four regions in general status had Morphometric significant differences based on One Way ANOVA Analysis. Meanwhile Anzali wetland Bream with Caspian Sea Bream from 41 Morphometric surveyed factors in 33 factors, with Aras Darn Lake Bream in 41 factors, with Azerbkjan republic Bream in 41 factors,Caspian Sea Bream with Aras Darn Lake Bream in 36 factors,with Azerbijan republic B ream in 40 factors and A ras Dam L ake Bream with Azerbijan republic Bream in 38 factors had significant statistical differences. These four regions Bream had differences according to the Morphomertric specification ration based on One Way ANOVA Analysis. Also Anzali wetland Bream was surveyed with Caspian Sea Bream from 37 factors i n 27 factors, Anzali wetland Bream with Aras Dam 1ake in 37 factors Anzali wetland Bream with Azerbijan republic Bream in 32 factors,Caspian sea bream with Arsa Dam Lake Bream in 26 factors, Caspian Sea Bream with Azerbijan republic Bream in 29 factors and Aras Dam Lake Bream with Azerbijan republic Bream in 34 factor had significant statistical differences. Based on Meristic factor of four regions bream in 16 surveyed factors in 10 factors had meaningful differences according to the One Way ANOVA Analysis. While Anzali wetland Bream was surveyed with Caspian Sea Bream from in 3 factors,Anzali wetland Bream with Aras Dam lake in 8 factors,Anzali wetland Bream with Azerbijan republic B ream in 6 factors,Caspian Sea bream with Arsa Dam Lake Bream in 6 factors,Caspian sea Bream with Azerbijan republic Bream in 3 factors and Aras Dam Lake Bream with Azerijan republic Bream in 8 factor had significant statistical differences.Meanwihle based on Factor Analysis and Discriminant Breams had differences. Also according to the resrarchs Anzali wetland Bream in 0+ age group till 5+ (6 age groups),Caspian Sea bream in 1+ - 5+(5 age groups),Aras Darn Lake Bream in 1+ - 7+ (7 age groups) and Azerbijan republic Bream for Morphometric and Meristic studies in 1+age group and for molecular Genetic reaserch were in 8+and 9+ age groups. According to the research 4 ecosystems Bream in status of same age, Aras lake Bream were bigger according to weight and length.Also in this research genetic diversity between four population was researched by PCR-RFLP technic on a piece of mitochondrion genome with the length of 3500bp contain of tRNA-leu,tRNA-glu,ND5/6,Cytb. Between 17 used enzyme. 4 enzyme, Dral, Bc11, Haefll and Banff showed diversity in totally 6 composite haplotype was detected. Maximum nucleotide diversity by the value% 0/58 in Azerbijan republic Bream by all haplotype. Aras darn Lake Bream had 2 haplotype and nucleotide diversity of %0/35.Anzali wetland and Caspian Sea Bream had no diversity. Statistical analysis by the usage of Monte Carlo with 1000 repeat showed significant differences between Azerbaijan Bream and other Bream(P<0/0001) but there was no significant difference between 3 regions Bream(P>0/5).

Phylogenetic and systematic study of the genus Bombina (Amphibia : Anura : Bombinatoridae): New insights from molecular data

Phylogenetic relationships and systematics of the eight currently recognized species of the genus Bombina were investigated using four mitochondrial gene fragments (16S rRNA, 12S rRNA, ND4-tRNA(LEU), and cytochrome b). We prepared two different concatenat

Quantitative relationship between chromatographic retentions and molecular structures of polychlorinated dibenzo-p-dioxins (PCDDs)

A new approach to study the quantitative relationships between chromatographic retentions and molecular structures of polychlorinated dibenzo-p-dioxins (PCDDs) is described. The retention equations of PCDDs log k' = A + B/T in gas chromatography (GC) are used to evaluate the properties of the regression coefficients A and B, which have been widely accepted as highly reliable chromatographic retentions. The quantitative relationships between the A, B values and the molecular structures are found. The molecular descriptors given for the first time in this article are very effective. As a result, the regression equations are derived with correlation coefficients greater than 0.9995. The A, B values of PCDDs with no standards available have been predicted according to these relationships. They are very useful in chromatographic identification. The retention times of all PCDDs can be conveniently predicted at any temperature program. Compared with the data obtained from the relevant experiments, the results of prediction are very accurate. (C) 2000 Elsevier Science Ltd. All rights reserved.

SbOx/SiO2 catalysts for the selective oxidation of methane to formaldehyde using molecular oxygen as oxidant

SbOx and SbOx/SiO2 catalysts were prepared and investigated for methane selective oxidation to HCHO. HCHO selectivity up to 41% can be obtained on Sb2O5/SiO2 catalyst at 873 K and just drop gently to 18% with temperature up to 923 K. HCHO selectivity for SbOx/SiO2 catalysts decreases gently with reaction temperature, so considerable value of HCHO selectivity can still be obtained at high temperatures.

Lateral habits of single crystals of metallocene-catalyzed low molecular weight short chain branched polyethylene from the melt

The lateral habits of low molecular weight short chain branched polyethylene single crystals from the melt were studied. Three crystallization temperatures (102, 104 and 106 degrees C) were selected for single crystal growth. It was found that the lateral habits of single crystals were asymmetric at all the crystallization temperatures selected. The electron diffraction patterns and tilting series experiments evidenced that there existed chain tilting in all the lamellae. It was the chain tilting that lead to the asymmetry of the growth rate and of lateral habits of the single crystals about the b-axis. The lateral habits substantially changed from the growth at 102 degrees C where the truncated lozenge single crystals formed with straight (110) faces to the growth at 104 degrees C where the lenticular single crystals appeared. This change occurred at 20 degrees C lower than that in a low molecular weight linear polyethylene with the same molecular weight. Furthermore, kinetics theory analysis evidenced that the change of lateral habits from truncated lozenge to lenticular shape resulted from the transition of growth regime. The results were the same as that of high molecular weight linear polyethylene but different to that of low molecular weight linear polyethylene. It may be attributed by the existence of short branched chains. (C) 2000 Elsevier Science Ltd. All rights reserved.

The relation between formal potential and structure of indophenols and molecular mechnism of electrooxidation

The molecular structural parameters of indophenol and its derivatives were calculated by semi-empirical molecular orbital quantum chemical method,The relation between molecular structural parameters and formal potentials was analyzed by principal factor analysis and multiple Linear regression method. It was found that the formal potential of indophenols has a good relation with two-center electron exchange energy, E-ex (2), resonance energy of O-C bond, E-ex (C-1-O), and molecular ionization potential, I-p, among 19 moleclular structural parameters. The regression equation is E-0' = 1. 47 x 10 (-3) E-ex (two) - 5. 74 x 10 (-2) E-ex (C-1 - O) - 1. 41 x 10 (-2) I-p with RC = 0. 9999 and SD = 0. 00424. It was confirmed by the relation between structure parameters and formal potentials, and the thermodynamic stability of its intermediate products that the H (+) ionization is prior to the electron transfer step in the oxidation mechanism.