Neurological trypanosomiasis in quinapyramine sulfate-treated horses—a breach of the blood–brain barrier?

Trypanosoma evansi infection typically produces wasting disease, but it can also develop into a neurological or meningoencephalitis form in equids. Trypanosomiasis in horses was treated with quinapyramine sulfate, and all the 14 infected animals were recovered clinically. After clinical recovery, four animals developed a neurological form of the disease at various intervals. Two of these animals treated with diminazene aceturate recovered temporarily. Repeated attempts failed to find the parasite in the blood or the cerebrospinal fluid (CSF), but all of the animals were positive in enzyme-linked immunosorbent assay. The calculation of the antibody index (AI) in the serum and the CSF and polymerase chain reaction (PCR) analysis of the CSF and brain tissue were carried out to confirm the neuro-infection. We found PCR and AI analyses of the CSF to be useful tools in the diagnosis of the neurological form of trypanosomiasis when the organism cannot be found in the blood or CSF. The increased albumin quotient is indicative of barrier leakage due to neuroinflammation. The biochemical changes in the CSF due to nervous system trypanosomiasis include increases in the albumin quotient, total protein, and urea nitrogen. It seems to be the first report on relapse of the nervous form of trypanosomiasis in equids even after quinapyramine treatment in endemic areas.     

Activation of integrin alphaIIbbeta3 by modulation of transmembrane helix associations

Transmembrane helices of integrin alpha and beta subunits have been implicated in the regulation of integrin activity. Two mutations, glycine-708 to asparagine-708 (G708N)and methionine-701 to asparagine-701, in the transmembrane helix of the beta3 subunit enabled integrin alphaIIbbeta3 to constitutively bind soluble fibrinogen. Further characterization of the G708N mutant revealed that it induced alphaIIbbeta3 clustering and constitutive phosphorylation of focal adhesion kinase. This mutation also enhanced the tendency of the transmembrane helix to form homotrimers. These results suggest that homomeric associations involving transmembrane domains provide a driving force for integrin activation. They also suggest a structural basis for the coincidence of integrin activation and clustering.     

Evaluation of combined Pasteurella vaccines in control of sheep pneumonia

The effectiveness of an oil adjuvant vaccine (OAV) incorporating locally isolated strains of Pasteurella haemolytica type 7 and Pasteurella multocida types A and D was compared with that of Carovax (Wellcome Laboratories) in imported cross-bred lambs. The criterion of efficacy was the ability of the vaccines to reduce the extent of pneumonic lesions in vaccinated as against unvaccinated control lambs. The OAV produced at this Institute significantly reduced the lung lesions at P less than 0.05 level compared with its control group when challenged with P. haemolytica alone. However, the vaccine was unsatisfactory against P. multocida or combined P. multocida P. haemolytica challenge. Carovax did not produce any significant reduction in the lung lesions caused by P. haemolytica and/or P. multocida.     

Immunostimulatory effect of water soluble fraction of Nyctanthes arbortristis leaves on the immune response in Oreochromis mossambicus (Peters)

Use of immunostimulants as a prophylactic measure against diseases in fish is considered as an effective alternative to antibiotic use. Plant‐derived immunostimulants have recently received more attention, as most of them are cost‐effective and eco‐friendly. This study was carried out with the objective of evaluating the possible immunostimulatory activity of intraperitoneally injected water soluble fraction of Nyctanthes arbortristis (an Indian medicinal plant) leaves on (i) specific immunity (antibody response), (ii) nonspecific immunity (Lysozyme activity, ROS production) and (iii) functional immunity in terms of disease resistance against Aeromonas hydrophila in Oreochromis mossambicus. The results of the study showed that all the tested doses (i.e. 3.2, 16, 80 and 400 mg kg^?1) of water soluble fraction of Nyctanthes arbortristis leaves significantly enhanced both primary and secondary antibody responses to heat killed A. hydrophila. Significant enhancement in serum lysozyme activity by all the doses of water soluble fraction was observed on day 10. The lower doses of 3.2 and 16 mg kg^?1 of water soluble fraction alone enhanced intracellular ROS production. Fish treated with both single and double dose of water soluble fraction showed maximum disease resistance. The highest dose (400 mg kg^?1) of water soluble fraction exhibited highest relative per cent survival in both single dose and double dose groups.     

Toxicity of diafenthiuron to honey bees in laboratory,semi‐field and field conditions

BACKGROUND: Cardamom, an important spice crop often attacked by many insect pests, is controlled mainly using synthetic insecticides. As honey bees play a vital role in pollination in cardamom, the impact of insecticides on honey bees needs to be explored to assess its safety. RESULTS: Risk assessment based on contact toxicity revealed diafenthiuron to be a non‐selective insecticide to bees with a low selectivity ratio (the ratio between the LD₅₀ for beneficial and pest species). A dose of diafenthiuron that killed 90% of cardamom borer, Conogethes punctiferalis Guenee, was found to kill 100% of Indian bees. Based on the hazard ratio (the ratio between the field‐recommended dose and the LD₅₀ for the beneficial), diafenthiuron was found to be slightly to moderately toxic to bees. Diafenthiuron, even at low concentrations of LC₁ (the concentration that killed 1% of bees), was found to affect the foraging and homing behaviour of Indian bees. Of bees fed with 30 µg mL^?1 of diafenthiuron, 40% were found missing on the third day after exposure. However, diafenthiuron did not affect bee visits to the cardamom fields. CONCLUSION: Diafenthiuron is more highly toxic to Apis cerana indica F. than to C. punctiferalis by contact, using selectivity ratio and probit substitution methods of risk assessment, but the hazard ratio revealed diafenthiuron to be a slightly to moderately toxic chemical. Diafenthiuron was found to affect the foraging and homing behaviour of bees at sublethal concentrations. Thus, sublethal effects are more relevant in risk assessment than lethal and acute effects. Copyright © 2010 Society of Chemical Industry     

Management of cardamom borer,Conogethes punctiferalis Guenee and thrips,Sciothrips cardamomi Ramk using diafenthiuron and its residues in fresh and cured cardamom capsules

Cardamom is an important spice crops used all over the world as a flavoring agent of food materials. The productivity is limited by insect pests and thus effective insecticide which does not leave residues in the produce is the need of the hour. Diafenthiuron 50 WP @ 300 g a.i ha^?1 was found effective in managing both the cardamom shoot and capsule borer, Conogethes punctiferalis Guenee and thrips, Sciothrips cardamomi Ramk and thus can be recommended for pest management. Cardamom capsules were collected from the plants that were sprayed with diafenthiuron at the recommended dose of 200 g a.i ha^?1 and double the dose (400 g a.i ha^?1), which were then analyzed under HPLC with a normal phase column. The diafenthiuron residue was below the detectable levels of 0.05 µg g^?1 in the harvested produce (both fresh and cured) after twelve and fourteen days of spray. So, capsules can be harvested safely without any risk of insecticide residues 12 days after spraying of diafenthiuron and thus can be recommended for usage in cardamom plantations.     

The Challenge of Ecophysiological Biodiversity for Biotechnological Applications of Marine Microalgae

In this review, we aim to explore the potential of microalgal biodiversity and ecology for biotechnological use. A deeper exploration of the biodiversity richness and ecophysiological properties of microalgae is crucial for enhancing their use for applicative purposes. After describing the actual biotechnological use of microalgae, we consider the multiple faces of taxonomical, morphological, functional and ecophysiological biodiversity of these organisms, and investigate how these properties could better serve the biotechnological field. Lastly, we propose new approaches to enhancing microalgal growth, photosynthesis, and synthesis of valuable products used in biotechnological fields, mainly focusing on culture conditions, especially light manipulations and genetic modifications.     

Neem oil (Azadirachta indica) nanoemulsion--a potent larvicidal agent against Culex quinquefasciatus

BACKGROUND: Nanoemulsion composed of neem oil and non‐ionic surfactant Tween 20, with a mean droplet size ranging from 31.03 to 251.43 nm, was formulated for various concentrations of the oil and surfactant. The larvicidal effect of the formulated neem oil nanoemulsion was checked against Culex quinquefasciatus. RESULTS: O/W emulsion was prepared using neem oil, Tween 20 and water. Nanoemulsion of 31.03 nm size was obtained at a 1:3 ratio of oil and surfactant, and it was found to be stable. The larger droplet size (251.43 nm) shifted to a smaller size of 31.03 nm with increase in the concentration of Tween 20. The viscosity of the nanoemulsion increased with increasing concentration of Tween 20. The lethal concentration (LC₅₀) of the nanoemulsion against Cx. quinquefasciatus was checked for 1:0.30, 1:1.5 and 1:3 ratios of oil and surfactant respectively. The LC₅₀ decreased with droplet size. The LC₅₀ for the ratio 1:3 nanoemulsions was 11.75 mg L^?1. CONCLUSION: The formulated nanoemulsion of 31.03 nm size was found to be an effective larvicidal agent. This is the first time that a neem oil nanoemulsion of this droplet size has been reported. It may be a good choice as a potent and selective larvicide for Cx. quinquefasciatus. Copyright © 2011 Society of Chemical Industry     

Response of maize to mycorrhizal colonization at varying levels of zinc and phosphorus

A greenhouse experiment was conducted in a red sandy loam soil (Alfisol) to study the responses of arbuscular mycorrhizal (AM) fungus Glomus intraradices Schenck & Smith inoculated (M+) and uninoculated (M−) maize (Zea mays L) plants exposed to various levels of P (15 and 30 mg kg⁻¹) and Zn (0, 1.25, and 2.5 mg kg⁻¹). Roots and shoots were sampled at 55 and 75 days after sowing and assessed for their nutritional status, root morphology, and root cation exchange capacity (CEC) besides grain quality. Mycorrhizal plants had longer and more extensive root systems than nonmycorrhizal plants, indicating that M+ plants are nutritionally rich, especially with P, which directly assisted in the proliferation of roots. Further, root CEC of M+ plants were consistently higher than those of M− plants, suggesting that mycorrhizal colonization assists in the acquisition of nutrients from soil solution. Mycorrhizal inoculated plants had significantly (P ≤ 0.01) higher P and Zn concentrations in roots, shoots, and grains, regardless of P or Zn levels. The available Zn and P status of AM fungus-inoculated soils were higher than unioculated soils. The data suggest that mycorrhizal symbiosis improves root morphology and CEC and nutritional status of maize plants by orchestrating the synergistic interaction between Zn and P besides enhancing soil available nutrient status that enables the host plant to sustain zinc-deficient conditions.