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1.
In order to study the epitopes in fibrin towards which monoclonal antibodies are directed we needed the pure individual polypeptide chains of human fibrinogen in reasonable quantity. We report here a simplified, rapid method of separation of high-purity human fibrinogen chains. Following reduction and S-carboxymethylation of human fibrinogen, the sample was injected directly onto a column of the polymeric reversed-phase perfusion packing POROS 20-R2, and the chains were completely resolved in less than 3 min at a flow-rate of 10 ml/min. The capacity was equivalent to that of a similar sized conventional silica-based column. However the throughput was approximately five to ten times as high. The column was durable and robust in day-to-day use.  相似文献   
2.
The molecular pathogenesis of avian influenza infection varies greatly with individual bird species and virus strain. The molecular pathogenesis of the highly pathogenic avian influenza virus (HPAIV) or the low pathogenic avian influenza virus (LPAIV) infection in avian species remains poorly understood. Thus, global immune response of chickens infected with HPAI H5N1 (A/duck/India/02CA10/2011) and LPAI H9N2 (A/duck/India/249800/2010) viruses was studied using microarray to identify crucial host genetic components responsive to these infection. HPAI H5N1 virus induced excessive expression of type I IFNs (IFNA and IFNG), cytokines (IL1B, IL18, IL22, IL13, and IL12B), chemokines (CCL4, CCL19, CCL10, and CX3CL1) and IFN stimulated genes (OASL, MX1, RSAD2, IFITM5, IFIT5, GBP 1, and EIF2AK) in lung tissues. This dysregulation of host innate immune genes may be the critical determinant of the severity and the outcome of the influenza infection in chickens. In contrast, the expression levels of most of these genes was not induced in the lungs of LPAI H9N2 virus infected chickens. This study indicated the relationship between host immune genes and their roles in pathogenesis of HPAIV infection in chickens.  相似文献   
3.
The daily number of IV instar larva of Culex quinquefasciatus killed, rate of pupation and adult emergence was noted in presence of the predatory water bug Sphaerodema annulatum for a period of seven consecutive days, experimentally, in the laboratory. The rate of IV instar larva killed by the water bugs on an average was 65.17 per day. The rate of pupation ranged between 7.6 and 48 in control while in presence of water bugs it ranged between 6 and 35. The rate of adult emergence in control experiments varied between 1.4 and 4.8 per day, which was reduced to only 0.4-28.8 per day in case of the water bugs. The results clearly indicate that the water bugs on its way of predation reduces the rate of pupation and adult emergence of Cx. quinquefasciatus significantly which calls for an extensive field trials.  相似文献   
4.
Following repeated administration of factor VIII (FVIII), a significant number of hemophilia A patients develop antibodies (Abs), inhibiting the procoagulant activity of infused FVIII. We have designed an approach based on the blocking of the deleterious activity of these Abs by peptide decoys mimicking the anti-FVIII Ab epitopes. Here, the well characterized inhibitory monoclonal Ab ESH8 served as a model. Several phage peptide libraries were screened for specific binding to ESH8. Seven constrained dodecapeptide sequences were obtained. Six sequences carried the consensus motif, hydrophobic-(Y/F)GKTXL. This motif showed a certain similarity with the (2231)QVDFQKTMKV(2240) sequence of the C(2) domain. In the seventh sequence, YCNPSIGDKNCR, the residues GDKN are similar to the sequence (2267)DGHQ(2270). Upon inspection of the C(2) domain crystallographic structure, the two stretches QVDFQKTMKV and DGHQ appeared close together in space and might constitute a discontinuous epitope. Corresponding synthetic peptides were able to inhibit the binding of ESH8 to FVIII in a specific and dose-dependent manner. Moreover, the ability of the selected peptides to neutralize the inhibitory activity of ESH8 was demonstrated in functional tests as well as in vivo in a murine model of hemophilia A. This study demonstrates the potential of this approach to neutralize the activity of potent inhibitory Abs.  相似文献   
5.
The sewage snail Physa acuta is a serious threat to certain economic plants and to the purification plant of sewage works by rendering the biofilters ineffective. Various attempts are being made to control it. The efficacy of the predacious water bugs Sphaerodema rusticum was judged experimentally, in the laboratory in the potential control of P. acuta. It is revealed that, when supplied separately, the first, second and third instar and the adult S. rusticum did not attack P. acuta belonging to 3.1-8 mm, 5.1-8 mm, 7.1-8 mm and 相似文献   
6.
Aim To study (1) the large-scale distribution patterns of freshwater fishes in the Western Ghats of India; (2) the endemism and uniqueness of the fishes in various zones; and (3) the threat status of fishes by categorizing them under low risk (LR), vulnerable (VU), endangered (EN) and critically endangered (CR). Location The Western Ghats of India. Methods The scientific literature describing the freshwater fishes of the Western Ghats was reviewed. Data describing the lists of the species were extracted and complied. The species accumulation curve was plotted using Michaelis–Menten-like equation. The Western Ghats was divided into six zones and similarity of the species was calculated using Jacquard's index. Results Literature to date records 288 species belonging to 12 orders, 41 families and 109 genera, of which 118 species are endemic and 51 are unique. However, the species accumulation curve shows that there might be 345 species in this region, indicating that 16% species have not been recorded to date. An analysis of the distribution pattern of fishes in the Western Ghats suggests that the southern region is more diverse than the northern and central regions. The southern region shows high endemism and high uniqueness while the northern region shows high endemism but less uniqueness. The similarity index between the zones indicates that as the distance between the zones increases similarity decreases. The status of 105 of 288 species was not known due to data deficiency but among the remaining 183 species, 58 species were categorized as LR, 41 as VU, 54 as EN, 24 as CR while the remaining six species were introduced. Conclusions The distribution patterns of fishes in the Western Ghats are discussed in accordance with the geography of Western Ghats, its climatic conditions and ‘Satpura Hypothesis’. The threat status of fishes found in Western Ghats suggests that at least 41% of fish fauna is threatened by either being VU, EN or CR. Implication of potent conservation measures is necessary to conserve the fish fauna of Western Ghats.  相似文献   
7.
The styryl group of dyes has been used in cellular studies for over 20 years because of their solvatochromic and/or electrochromic properties. Here we report characterization of solubility and solvatochromic properties of a near infra-red styryl dye, styryl 11 or LDS 798. We have extended our studies to small unilamellar vesicles and lipid based nanoparticles and found that solvatochromic properties of this dye used in tandem with fluorescence correlation spectroscopy can be used to efficiently determine the diffusion coefficient and hence the size of the submicron lipid based particles. This technique has the potential to provide essential information about liposomal and vesicular structures and their movement in vitro and in situ.  相似文献   
8.
In this experimental study, we investigated whether l-ascorbic acid has any influence on the blood antioxidant defense system, lipid peroxidation and hematological parameters of the albino rats exposed to nickel sulfate(NiSO4).Twenty four adult rats were divided into four groups of six animals in each group. The control rats were untreated and comprised Group I. Group II rats were administered nickel sulfate (2.0 mg/100 g b.wt.; intraperitonially, i.p.). Group II rats were treated orally l-ascorbic acid (50 mg/100 g b.wt.) and Group IV rats were given both nickel sulfate and l-ascorbic acid simultaneously on alternate days until the tenth dose. The hematological parameters were assessed: red blood corpuscle counts, packed cell volume %, hemoglobin concentration, white blood corpuscle counts and platelets count decreased significantly and clotting time increased significantly in nickel treated rats. We also observed increase malondialdehyde (MDA) and decrease glutathione level (GSH) in erythrocytes of nickel treated rats. The activities of erythrocyte antioxidant enzymes like superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were significantly increased in rats treated with nickel sulfate. Simultaneously treatment of l-ascorbic acid exhibited a possible protective role on the toxic effect of nickel sulfate on the hematological values, erythrocyte MDA and GSH concentrations as well as antioxidant enzymatic defense system.  相似文献   
9.
Vaccinia virus encodes a structural and functional homolog of human complement regulators named vaccinia virus complement control protein (VCP). This four-complement control protein domain containing secretory protein is known to inhibit complement activation by supporting the factor I-mediated inactivation of complement proteins, proteolytically cleaved form of C3 (C3b) and proteolytically cleaved form of C4 (C4b) (termed cofactor activity), and by accelerating the irreversible decay of the classical and to a limited extent of the alternative pathway C3 convertases (termed decay-accelerating activity [DAA]). In this study, we have mapped the VCP domains important for its cofactor activity and DAA by swapping its individual domains with those of human decay-accelerating factor (CD55) and membrane cofactor protein (MCP; CD46). Our data indicate the following: 1) swapping of VCP domain 2 or 3, but not 1, with homologous domains of decay-accelerating factor results in loss in its C3b and C4b cofactor activities; 2) swapping of VCP domain 1, but not 2, 3, or 4 with corresponding domains of MCP results in abrogation in its classical pathway DAA; and 3) swapping of VCP domain 1, 2, or 3, but not 4, with homologous MCP domains have marked effect on its alternative pathway DAA. These functional data together with binding studies with C3b and C4b suggest that in VCP, domains 2 and 3 provide binding surface for factor I interaction, whereas domain 1 mediates dissociation of C2a and Bb from the classical and alternative pathway C3 convertases, respectively.  相似文献   
10.
Radioprotective effect of aqueous extract of Ocimum sanctum (40 mg/kg body weight, for 15 days) in mice exposed to high-doses (3.7 MBq) of oral 131iodine was investigated by studying the organ weights, lipid peroxidation and antioxidant defense enzymes in various target organs like liver, kidneys, salivary glands and stomach at 24 hr after exposure in adult Swiss mice. The mean weight of the salivary glands showed significant increase after 131iodine administration. 131iodine exposure significantly increased lipid peroxidation in kidneys and salivary glands in comparison to control animals. Pretreatment with O. sanctum in radioiodine exposed group showed significant reduction in lipid peroxidation in both kidneys and salivary glands. In liver, reduced glutathione (GSH) levels showed significant reduction after radioiodine exposure while pretreatment with O. sanctum exhibited less depletion in GSH level even after 131iodine exposure. However, no such changes were observed in stomach. The results indicate the possibility of using aqueous extract of O. sanctum for ameliorating 131Iodine induced damage to the salivary glands.  相似文献   
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