A new epithelial cell line,HBF from caudal fin of endangered yellow catfish,Horabagrus brachysoma (Gunther, 1864)

A new epithelial cell line, Horabagrus brachysoma fin (HBF), was established from the caudal fin tissue of yellow catfish, H. brachysoma and characterized. This HBF cell line was maintained in Leibovitz’s-15 medium supplemented with 15 % fetal bovine serum (FBS) and subcultured more than 62 times over a period of 20 months. The HBF cell line consists predominantly of epithelial cells and is able to grow at temperatures between 20 and 35 °C with an optimum temperature of 28 °C. The growth rate of these cells increased as the proportion of FBS increased from 5 to 20 % at 28 °C with optimum growth at the concentrations of 15 % FBS. Partial amplification and sequencing of fragments of two mitochondrial genes 16S rRNA and COI confirmed that HBF cell line originated from yellow catfish. The HBF cells showed strong positive reaction to the cytokeratin marker, indicating that it was epithelial in nature. HBF cell line was inoculated with tissue homogenate from juveniles of Sea bass, Lates calcarifer infected with viral nervous necrosis virus (VNNV) and found not susceptible to VNNV. The extracellular products of Vibrio cholerae MTCC 3904 were toxic to the HBF cells. These cells were confirmed for the absence of Mycoplasma sp by PCR.     

A Rapid and Efficient Method for In Vitro Screening of Taro for Leaf Blight Disease Caused by Phytophthora colocasiae

Taro leaf blight caused by Phytophthora colocasiae presents the single biggest constraint for taro cultivation globally. To accelerate breeding and selection for disease resistance to leaf blight, it is important to develop bioassays which could differentiate resistant and susceptible cultivars efficiently. In this study, thirty taro accessions and four released cultivars were evaluated for resistance to leaf blight using a modified floating leaf disc assay. A novel method for mass production of P. colocasiae zoospores was developed and used as inoculum for the assay. There were significant (P < 0.05) differences among accessions in their response to P. colocasiae infection in the detached leaf assay. The accessions could be efficiently classified into various resistance groups based on a 0–4 score. Also, the assay results were consistent with the field evaluation scores of taro accessions. Thus, this study reports the development of a rapid, simple and repeatable assay that can be used to screen large numbers of taro cultivars for resistance to P. colocasiae.     

Genetics and genomics of susceptibility and immune response to necrotic enteritis in chicken: a review

Global poultry production is facing many challenges and is currently under pressure due to the presence of several diseases like Necrotic Enteritis (NE). It is estimated that NE-caused global economic losses has increased from 2 billion to 6 billion US$ in 2015 because it is not easy to diagnose and control disease at the earlier stage of occurrence. Additionally, ban on the in-feed antibiotics and some other genetic and non-genetic predisposing factors affect the occurrence of the disease. Though the incidence of the disease can be reduced by minimizing the predisposing factors and through immunization of birds but there is no single remedy to control the disease. Therefore, we suggest that there is need to find out the genetic variants that could help to select the birds resistant to NE. The current review details the pertinent features about the genetic and genomics of susceptibility and immune response of birds to Necrotic Enteritis. We report here the list of candidate gene reported for their involvement with the susceptibility and/or resistance to the disease. However, most of these genes are involved in immune-related functions. For better understanding of the role of Clostridium perfringens and its toxins in the pathogenesis of disease there is need to unveil the association between any specific genetic variation and clinical status of NE. However, the presence of substantial genetic variations among different breeds/strains of chicken shows that it is possible to develop broiler strain with genetic resistant against NE. It would help in the cost-effective and sustainable production of safe broiler meat.     

Comparative Assessment of Genetic Variability in the Populations of Endemic and Endangered Yellow Catfish, Horabagrus brachysoma (Teleostei: Horabagridae), Based on Allozyme, RAPD, and Microsatellite Markers

The comparative assessment of genetic diversity using allozymes, random amplified polymorphic DNA (RAPD), and microsatellite markers was conducted in endemic and endangered yellow catfish (Horabagrus brachysoma) sampled from three locations in Western Ghats river systems of India. Among the three markers, microsatellites show more polymorphism, having 100% polymorphic loci, whereas allozymes show the least (56%). In RAPD, 60.5% of fragments were polymorphic. Observed heterozygosity and F(ST) values were very high in microsatellites, compared with the other markers. Microsatellite and RAPD markers reported a higher degree of genetic differentiation than allozymes among the populations depicted by pairwise F(ST)/G(ST), AMOVA, Nei's genetic distance, and UPGMA dendrogram. The three classes of markers demonstrated striking genetic differentiation between pairs of H. brachysoma populations. The data emphasize the need for fishery management, conservation, and rehabilitation of this species.     

Effect of W–TiO2 composite to control microbiologically influenced corrosion on galvanized steel

Microorganisms tend to colonize on solid metal/alloy surface in natural environment leading to loss of utility. Microbiologically influenced corrosion or biocorrosion usually increases the corrosion rate of steel articles due to the presence of bacteria that accelerates the anodic and/or cathodic corrosion reaction rate without any significant change in the corrosion mechanism. An attempt was made in the present study to protect hot-dip galvanized steel from such attack of biocorrosion by means of chemically modifying the zinc coating. W–TiO₂ composite was synthesized and incorporated into the zinc bath during the hot-dipping process. The surface morphology and elemental composition of the hot-dip galvanized coupons were analyzed by scanning electron microscopy and energy dispersive X-ray spectroscopy. The antifouling characteristics of the coatings were analyzed in three different solutions including distilled water, seawater, and seawater containing biofilm scrapings under immersed conditions. Apart from electrochemical studies, the biocidal effect of the composite was evaluated by analyzing the extent of bacterial growth due to the presence and absence of the composite based on the analysis of total extracellular polymeric substance and total biomass using microtiter plate assay. The biofilm-forming bacteria formed on the surface of the coatings was cultured on Zobell Marine Agar plates and studied. The composite was found to be effective in controlling the growth of bacteria and formation of biofilm thereafter.     

Development and Characterization of RAPD and Microsatellite Markers for Genetic Variation Analysis in the Critically Endangered Yellow Catfish <Emphasis Type="Italic">Horabagrus nigricollaris</Emphasis> (Teleostei: Horabagridae)

Random-amplified polymorphic DNA (RAPD) and microsatellite markers were developed and used for the analysis of genetic variability in the critically endangered yellow catfish Horabagrus nigricollaris, sampled from the Chalakkudy River, Kerala, India. Eight RAPD and five microsatellite markers were detected to genotype the species. In RAPD, the 73 fragments were 20.55% polymorphic, whereas 4 polymorphic loci (80%) were obtained in microsatellites. In microsatellites, the number of alleles across the 5 loci was 1-5, and the range of heterozygosity was 0.25-0.5. The mean observed number of alleles was 2.4, and the effective number was 1.775 per locus. The average heterozygosity across all investigated samples was 0.29, indicating a significant deficiency of heterozygotes in this species. RAPD and microsatellite methods report a low degree of gene diversity and lack of genetic heterogeneity in the population of H. nigricollaris, emphasizing the need for fishery management, conservation, and rehabilitation of this species.     

Blood pressure modulation following activation of mast cells by cationic cell penetrating peptides

Short cell penetrating peptides (CPP) are widely used in vitro to transduce agents into cells. But their systemic effect has not been yet studied in detail. We studied the systemic effect of the cell penetrating peptides, penetratin, transportan and pro-rich, on rat hemodynamic functions. Intra-arterial monitoring of blood pressure showed that injection of the positively charged penetratin and transportan in a wide range of concentrations (2.5-320 μg/kg) caused highly significant transient decrease in the systolic and diastolic blood pressure in a dose dependent manner (p<0.01). Pretreatment with histamine receptors blockers or with cromolyn, a mast cell stabilizing agent, significantly attenuated this effect. Furthermore, in vitro incubation of these both peptides with mast cells line, LAD2, caused a massive mast cell degranulation. In vitro studies showed that these CPP in a wide range of concentrations were not cytotoxic without any effect on the survival of LAD2 mast cell line. In contrast, the less positively charged and proline-rich CPP, pro-rich, had no systemic effects with no effect on mast cell degranulation. Our results indicate that intravenously administrated positively charged CPP may have deleterious consequences due to their induced BP drop, mediated by mast cell activation. Therefore, the major effect of mast cell activation on BP should be considered in developing possible future drug therapies based on the injection of membrane-permeable and positively charged CPP. Nevertheless, lower levels of such CPP may be considered as a treatment of systemic high BP through moderate systemic mast cell activation.     

A membrane protein based biosensor: use of a phosphate--H+ symporter membrane protein (Pho84) in the sensing of phosphate ions

A label free biosensor for direct detection of inorganic phosphate based on potential-step capacitance measurements has been developed. The high-affinity Pho84 plasma membrane phosphate/proton symporter of Saccharomyces cerevisiae was used as a sensing element. Heterologously expressed and purified Pho84 protein was immobilized on a self-assembled monolayer (SAM) on a capacitance electrode. Changes in capacitance were recorded upon exposure to phosphate compared to the control substance, phosphate analogue methylphosphonate. Hence, even without the explicit use of lipid membranes, the Pho84 membrane protein could retain its capacity of selective substrate binding, with a phosphate detection limit in the range of the apparent in vivo K(m). A linear increase in capacitance was monitored in the phosphate concentration range of 5-25 μM. The analytical response of the capacitive biosensor is in agreement with that the transporter undergoes significant conformational changes upon exposure to inorganic phosphate, while exposure to the analogue only causes minor responses.     

Liquid-phase and dispersive liquid-liquid microextraction techniques with derivatization: recent applications in bioanalysis

Liquid phase microextraction (LPME), especially hollow fiber liquid-phase microextraction (HF-LPME), and dispersive liquid-liquid microextraction (DLLME) offer high enrichments of target analytes in a single step. The analytical usefulness of these techniques is significantly enhanced by coupling them with suitable derivatization methods. Due to their simplicity, diverse bioanalytical applications have recently been reported. This review focuses on the recent developments of the combined LPME (mainly HF-LPME and single drop microextraction (SDME)) and DLLME techniques with derivatization for the analysis of biological samples. A broad range of sample matrices such as urine, blood, plasma and human hair samples with various derivatization methods for polar or ionizable organic compounds will be considered. These techniques can also be extended to the determination of trace metal ions, such as the heavy metal ions (Hg, Pb, and Co) and Se. Future trends of the techniques will also be discussed.     

Local synthesis of complement component C3 regulates acute renal transplant rejection

Accumulating evidence suggests that innate immunity interacts with the adaptive immune system to identify potentially harmful antigens and eliminate them from the host. A central facet of innate immunity is complement, which for some time has been recognized as a contributor to inflammation in transplant rejection but without detailed analysis of its role in what is principally a T cell mediated process. Moreover, epithelial and vascular tissues at local sites of inflammation secrete complement components; however, the role of such local synthesis remains unclear. Here we show that the absence of locally synthesized complement component C3 is capable of modulating the rejection of renal allografts in vivo and regulating T-cell responses in vivo and in vitro. The results indicate that improved success in kidney transplantation could come from therapeutic manipulation of innate immunity in concert with T cell directed immunosuppression.