The substantive equivalence of transgenic (Bt and Chi) and non-transgenic cotton based on metabolite profiles

Compositional studies comparing transgenic with non-transgenic counterpart plants are almost universally required by governmental regulatory bodies. In the present study, two T₂ transgenic cotton lines containing chitinase (Line 11/57) and Bt lines (Line 61) were compared with non-transgenic counterpart. To do this, biochemical characteristics of leaves and seeds, including amino acids, fatty acids, carbohydrates, anions, and cations contents of the studied lines were analyzed using GC/MS, high-performance liquid chromatography (HPLC), and ion chromatography (IC) analyzers, respectively. polymerase chain reaction (PCR) and Western blot analyses confirmed the presence and expression of Chi and Bt genes in the studied transgenic lines. Although, compositional analysis of leaves contents confirmed no significant differences between transgenic and non-transgenic counterpart lines, but it was shown that glucose content of chitinase lines, fructose content of transgenic lines (Bt and chitinase) and asparagine and glutamine of chitinase lines were significantly higher than the non-transgenic counterpart plants. Both the transgenic lines (Bt and chitinase) showed significant decrease in the amounts of sodium in comparison to the non-transgenic counterpart plants. The experiments on the seeds showed that histidine, isoleucine, leucine, and phenylalanine contents of all transgenic and non-transgenic lines were the same, whereas other amino acids were significantly increased in the transgenic lines. Surprisingly, it was observed that the concentrations of stearic acid, myristic acid, oleic acid, and linoleic acid in the chitinase line were significantly different than those of non-transgenic counterpart plants, but these components were the same in both Bt line and its non-transgenic counterpart. It seems that more changes observed in the seed contents than leaves is via this point that seeds are known as metabolites storage organs, so they show greater changes in the metabolites contents comparing to the leaves.     

Sensitivity of marine fish thermal habitat models to fishery data sources

Statistical models built using different data sources and methods can exhibit conflicting patterns. We used the northern stock of black sea bass (Centropristis striata) as a case study to assess the impacts of using different fisheries data sources and laboratory‐derived physiological metrics in the development of thermal habitat models for marine fishes. We constructed thermal habitat models using generalized additive models (GAMs) based on various fisheries datasets as input, including the NOAA Northeast Fisheries Science Center (NEFSC) bottom trawl surveys, various inshore fisheries‐independent trawl surveys (state waters), NEFSC fisheries‐dependent observer data, and laboratory‐based physiological metrics. We compared each model''s GAM response curve and coupled them to historical ocean conditions in the U.S. Northeast Shelf using bias‐corrected ocean temperature output from a regional ocean model. Thermal habitat models based on shelf‐wide data (NEFSC fisheries‐dependent observer data and fisheries‐independent spring and fall surveys) explained the most variation in black sea bass presence/absence data at ~15% deviance explained. Models based on a narrower range of sampled thermal habitat from inshore survey data in the Northeast Area Monitoring and Assessment Program (NEAMAP) and the geographically isolated Long Island Sound data performed poorly. All models had similar lower thermal limits around 8.5℃, but thermal optima, when present, ranged from 16.7 to 24.8℃. The GAMs could reliably predict habitat from years excluded from model training, but due to strong seasonal temperature fluctuations in the region, could not be used to predict habitat in seasons excluded from training. We conclude that survey data source can greatly impact development and interpretation of thermal habitat models for marine fishes. We suggest that model development be based on data sources that sample the widest range of ocean temperature and physical habitat throughout multiple seasons when possible, and encourage thorough consideration of how data gaps may influence model uncertainty.     

Predicting potentially pathogenic effects of hRPE65 missense mutations: a computational strategy based on molecular dynamics simulations

The human retinal pigment epithelium-specific 65-kDa protein (hRPE65) plays a crucial role within the retinoid visual cycle and several mutations affecting either its expression level or its enzymatic function are associated with inherited retinal diseases such as Retinitis Pigmentosa. The gene therapy product voretigene neparvovec (Luxturna) has been recently approved for treating hereditary retinal dystrophies; however, the treatment is currently accessible only to patients presenting confirmed biallelic mutations that severely impair hRPE65 function, and many reported hRPE65 missense mutations lack sufficient evidences for proving their pathogenicity. In this context, we developed a computational approach aimed at evaluating the potential pathogenic effect of hRPE65 missense variants located on the dimerisation domain of the protein. The protocol evaluates how mutations may affect folding and conformation stability of this protein region, potentially helping clinicians to evaluate the eligibility for gene therapy of patients diagnosed with this type of hRPE65 variant of uncertain significance.     

Flexural and Dynamic Mechanical Properties of Alkali-Treated Coir/Pineapple Leaf Fibres Reinforced Polylactic Acid Hybrid Biocomposites

Polylactic acid(PLA)possesses good mechanical and biodegradability properties which make it a suitable material for polymer composites whereas brittleness and high costs limit its utilization in various applications.The reinforcement of natural fibres with biopolymers has been formed to be an efficient technique to develop composites having the ability to be fully biodegradable.This study concerns with the incorporation of various percentages of untreated and alkali-treated Coir Fibres(CF)and pineapple leaf fibres(PALF)in PLA biocomposites and characterizations of flexural,morphological and dynamic mechanical properties.Flexural properties showed that the treated C1P1 hybrid composites(C1P1A)displayed highest flexural strength(35.81 MPa)and modulus(5.28 GPa)among all hybrid biocomposites.Scanning Electron Micros-copy(SEM)revealed a behaviour of fibre-matrix adhesion in untreated treated biocomposites.SEM observation revealed good dispersion of the fillers in PLA.Dynamic mechanical analysis revealed that C1P1A showed highest glass transition temperature(Tg)and storage modulus(E')while untreated C3P7 displayed the least Tg and E'.Overall findings showed that alkali-treated hybrid biocomposites(CF/PALF/PLA)especially C1P1A have improved flexural properties,dynamic and morphological properties over untreated biocomposites.Success of these findings will provide attracting consideration of these hybrid biocomposites for various lightweight uses in a broad selection of industrial applications such as biomedical sectors,automobile,construction,electronics equipment,and hardware tools.     

Amplified fragment length polymorphism for genetic diversity assessment in globe artichoke

Globe artichoke (Cynara cardunculus L. var. scolymus L.) is a diploid (2n=2x=34), predominantly cross-pollinated plant native to the Mediterranean basin, and Italy contains the richest primary cultivated gene pool. Commercial production is mainly based on perennial cultivation of vegetatively propagated clones that are highly heterozygous and segregate widely when progeny-tested. Analysis of the artichoke genome by means of molecular markers has been limited to a few studies; here we report on the genetic relatedness among 118 artichoke accessions, including clones belonging to the same varietal type, two accessions of cultivated cardoon (C. cardunculus L. var. altilis DC.) and four accessions of wild cardoon [C. cardunculus L. var. sylvestris (Lamk) Fiori] as measured by amplified fragment length polymorphism (AFLP). Eight primer combinations yielded a total of 667 bands, of which 519 were polymorphic. Genetic similarities among accessions were calculated according to Jaccards Similarity Index and used to construct a dendrogram based on the unweighted pair group method using arithmetic averages. Our results demonstrate that AFLP markers can be useful in evaluating Cynara cardunculus genetic diversity and in classifying accessions to phylogenetic groups based on their genetic similarity values. Genetic variation among artichoke clones belonging to the same varietal type was in some cases higher than that found among accessions differently named and coming from different areas. The lowest Jaccards Similarity Index found within a varietal type can be considered as a threshold for the identification of accessions which share an analogous genetic background. This will enable the selection of representatives in order to develop and manage a germplasm core collection as well as the identification of suitable material for future artichoke breeding efforts.Communicated by J.S. Heslop-Harrison     

Molecular cloning of fungal xylanases: an overview

Xylanases have received great attention in the development of environment-friendly technologies in the paper and pulp industry. Their use could greatly improve the overall lignocellulosic materials for the generation of liquid fuels and chemicals. Fungi are widely used as xylanase producers and are generally considered as more potent producers of xylanases than bacteria and yeasts. Large-scale production of xylanases is facilitated with the advent of genetic engineering. Recent breakthroughs in genomics have helped to overcome the problems such as limited enzyme availability, substrate scope, and operational stability. Genes encoding xylanases have been cloned in homologous and heterologous hosts with the objectives of overproducing the enzyme and altering its properties to suit commercial applications. Owing to the industrial importance of xylanases, a significant number of studies are reported on cloning and expression of the enzymes during the last few years. We, therefore, have reviewed recent knowledge regarding cloning of fungal xylanase genes into various hosts for heterologous production. This will bring an insight into the current status of cloning and expression of the fungal xylanases for industrial applications.     

Malondialdehyde production from spermine by homogenates of normal and transformed cells

The oxidation of spermine in vitro by a mixture of polyamine oxidase and diamine oxidase from pig kidney gives rise to malondialdehyde via 3-aminopropanol as the intermediate. Conversely, with spermidine, under similar experimental conditions, no evidence could be obtained for malondialdehyde formation within the limits of sensitivity of the assay (2.0 nmol). The activities of both these enzymes show about a 2-fold increase in normal rat kidney cells (LA31 NRK) transformed by the temperature sensitive mutant of Rous sarcoma virus (LA31) and incubated at the non permissive temperature (39 degrees C) compared to the activities in LA31 NRK at the permissive temperature (33 degrees C). These same enzymatic activities show no temperature dependent changes in normal rat kidney cells (NRK) or in these same cells infected by the wild type virus (NRK B77). In extracts derived from Friend erythroleukemic cells induced to differentiate by dimethyl sulfoxide or hexamethylene bis acetamide, spermine oxidation takes place more efficiently than in non induced cells. A rise in diamine oxidase activity is seen in LA31 NRK (39 degrees C) 12 h after the temperature shift, whereas morphological manifestations of normalcy are seen only at 48 h. The Km of diamine oxidase is 10(-6) M for putrescine and 10(-3) M for 3-aminopropanol. A possible mechanism involving the well documented acetylation of putrescine [23,26] is proposed for diverting intracellular putrescine away from cytosolic diamine oxidase and towards intramitochondrial monoamine oxidase.     

A Comparative Oncology Study of Iniparib Defines Its Pharmacokinetic Profile and Biological Activity in a Naturally-Occurring Canine Cancer Model

Development of iniparib as an anti-cancer agent was hindered in part by lingering questions regarding its mechanism of action, the activity of its metabolites, and their potential accumulation in tumors. Due to strong similarities in metabolism of iniparib between humans and dogs, a veterinary clinical trial in pet dogs with spontaneous cancers was designed to answer specific questions pertaining to pharmacokinetic exposures and tolerability of iniparib. Dogs were treated with iniparib alone and in combination with carboplatin chemotherapy. Iniparib doses ranged between 10–70 mg/kg intravenously (IV). Plasma, tumor and normal tissue samples were collected before and at various time points scheduled after exposure for pharmacokinetic and biologic analysis. The primary endpoints included characterization of dose-limiting toxicities (DLT) and determination of the drug exposures that could be achieved in both normal and tumor tissues. Nineteen dogs were treated. DLT included fever, anorexia, diarrhea, neutropenia, and thrombocytopenia; most effects were attributable to carboplatin based on the timing of adverse event onset. The maximum tolerated dose (MTD) of iniparib was not identified. Moderate to high variability in plasma exposure was noted for iniparib and all metabolites between animals. When quantifiable, iniparib and metabolite plasma:tumor ratios were < 0.088 and <1.7, respectively. In this study, iniparib was well tolerated as a single agent and in combination with carboplatin over a range of doses. However, clinically relevant concentrations of the parent drug and selected metabolites were not detectable in canine tumor tissues at any studied dose, thus eliminating expectations for clinical responses in dogs or humans. Negative clinical trials in humans, and the uncertainties of its mechanism of action, ultimately led to the decision to stop clinical development of the drug. Nevertheless, the questions that can be asked and answered within the comparative oncology approach are evident from this successfully executed comparative clinical trial and exemplify the value of such studies in drug development.