A new species of the monogenea genus Heteromazocraes Mamaev, 1981, from a freshwater cyprinid Securicula gora (Ham.) from the Lucknow district,India

Heteromazocraes mamaevi n. sp. is described from a cyprinid, Securicula gora (Ham.) from the Lucknow district, India. It is characterised by well-developed cephalic glands, the shape of the genital spines, the structure of the egg and the shape of the clamp sclerites. This is the first record of the genus Heteromazocraes Mamaev, 1981 from a cyprinid fish.     

Biomass, Productivity and Energetics in Himalayan Alder Plantations

Biomass, net primary production and energy fixation in an agesequence of Himalayan alder (Alnus nepalensis D. Don) plantationswere estimated in the Kalimpong forest division of the easternHimalayas. Biomass in the plantations ranged from 106 t ha^–1(7-year stand) to 606 t ha^–1 (56-year stand) demonstratingthe potential of the alder for accumulating large biomass. Netprimary production and net energy fixation rates of the plantationswere reduced by nearly half in the 7-year stand (25 t ha^–1year^–1; 421 x 10⁶ kJ ha^–1 year^–1) comparedwith the 56-year stand (13 t ha^–1 year^–1; 215 x10⁶ kJ ha^–1 year^–1). Compartmental models of energystorage and flow rates were developed for the 7-year and 56-yearstands. The production efficiency, energy conversion efficiencyand energy efficiency in N₂ fixation have inverse relationshipswith plantation age. These efficiencies, when treated with eachother, showed significant exponential functions. Alnus nepalensis D. Don, Himalayan alder, plantation age, biomass, net primary production, energy flow, efficiencies     

DETECTION OF LISTERIA MONOCYTOGENES BY ADSORPTION AND ELUTION FROM HYDROPHOBIC MATRICES

The binding of L. monocytogenes Scott A strain to three hydrophobic matrices, octyl, phenyl and butyl Sepharose, was investigated. Optimal adsorption of L. monocytogenes to octyl Sepharose was obtained at pH 3.5 and 4 M NaCl. However, it was difficult to elute the bacteria from octyl Sepharose, even after changing the pH and lowering the salt concentration. Good adsorption of L. monocytogenes to phenyl Sepharose at pH 3.5 and 4 M NaCl was also observed. L. monocytogenes was found to adsorb weakly to butyl Sepharose, which is less hydrophobic than phenyl Sepharose. Bacteria were eluted under various conditions. The best elution was obtained with 10 mM sodium phosphate, followed by an increasing gradient of ethylene glycol. To test the potential application of hydrophobic chromatography for separating L. monocytogenes from food matrices, milk was inoculated with L. monocytogenes and then passed through a column of phenyl Sepharose at pH 3.5 and 4 M NaCl. Nearly all L. monocytogenes were bound to the hydrophobic gel and were eluted in a pure and viable form by changing the pH and lowering the salt concentration, and by using a polar reducing agent, ethylene glycol. This study shows that hydrophobic interaction chromatography can be used to separate L. monocytogenes from milk and may be applicable to other food suspensions. It is a gentle method that makes use of the hydrophobic surface properties of Listeria for attachment to hydrophobic gels, as well as using mild elution conditions to avoid inactivation of the organism.     

A greenhouse technique to screen pigeonpea for resistance to Heterodera cajani*

Heterodera cajani is an important nematode pest of pigeonpea in India and a simple and reliable greenhouse procedure has been developed to screen pigeonpea genotypes for resistance to it. In pot experiments, white cysts of H. cajani were counted on the roots of the susceptible genotype ICPL 87 at 15, 30 and 45 days after seedling emergence in soils infested with different levels of H. cajani. The seedlings were rated for the number of white cysts per root system on a one (highly resistant, no cysts) to nine (highly susceptible, more than 30 cysts) scale. White cysts were not easy to see on wet roots but were clearly visible on slightly dried roots. Cyst counts and ratings were more uniform when roots of 30 day old seedlings were evaluated than when 15 or 45 day old seedlings were examined. Effects of different H. cajani infestation levels on the ratings were not significant although the use of higher inoculum densities (16 to 27 eggs and juveniles/cm³ soil) was effective in reducing variability. This procedure was used to screen 60 pigeonpea genotypes and all of them were rated seven or nine. Ten accessions of Atylosia spp. and Rhynchosia spp. were rated three.     

Factors influencing oviposition behaviour of the sorghum midge, Contarinia sorghicola Coq.

Visual stimuli influence the orientation behaviour of the sorghum midge, Contarinia sorghicola Coq. (Diptera: Cecidomyiidae). Yellow, red and white colours are attractive to the midge while blue and black are least attractive. Sorghum panicles covered with blue- or black-coloured bags in a headcage showed maximum midge damage, while the reverse was true for panicles covered with yellow, red, and white coloured bags.
Panicles at half-anthesis with viable pollen and receptive stigmata suffered higher damage than those at the pre- and post-anthesis. Physical removal of anthers and stigmata significantly reduced the oviposition by the sorghum midge. Reduced oviposition/adult emergence was also recorded in male sterile sorghum lines (2219A and 296A) or through chemically- (Ethrel) (2-Chloro ethyl-phosphonic acid) induced male sterility in panicles of the sorghum cultivar, Swarna. Chemical stimuli from viable pollen and receptive stigmata and to a limited extent physical stimuli, govern the oviposition behaviour of the sorghum midge.
Sorghum cultivars IS 12573C, S-GIRL-MR1 and IS 2816C showed antixenosis to adult midges. However, these cultivars became susceptible under no-choice conditions in the headcage. DJ 6514 and IS 12666C were attractive to the adult midges, but showed antixenosis to oviposition under natural and no-choice conditions. Genotypes with short florets showed antixenosis for oviposition. Ovary and anther breadth and tannin content of grain showed negative associations with oviposition. Cultivar antixenosis to adult midges and oviposition is an important component of resistance to the sorghum midge.     

Human Epidermal Melanocyte and Keratinocyte Melanocortin Receptors: Visualization by Melanotropic Peptide Conjugated Microspheres (Latex Beads)

The objectives of this research were to determine whether melanocortin receptors are characteristic (constant) membrane markers of human epidermal melanocytes. Methodologies were developed to visualize melanotropin receptors by scanning electron microscopy (SEM). Multiple copies (up to a hundred) of [Nle⁴,D-Phe⁷]α-MSH, a superpotent analog of α-melanocyte stimulating hormone (α-MSH), were conjugated to a macromo-lecular carrier (latex beads: microspheres). Incubation in the presence of the melanotropin-conjugated microspheres resulted in binding of human normal epidermal melanocytes to the beads. Almost every (possibly all) melanocyte possesses melanocortin receptors as visualized by SEM. Specificity of binding of the macromolecular conjugate was demonstrated by several studies: 1) Binding of melanocytes to the microspheres was specific since it could be blocked by prior incubation of the cells in the presence of the unconjugated hormone analog; 2) microspheres lacking bound ligand did not bind to the melanocytes; 3) micro-spheres that were first treated with reducing agents (e.g., dithiothreitol) did not subsequently bind to melanocytes; 4) another peptide hormone ligand (e.g., a substance-P analog) attached to the latex beads failed to bind to the cells; 5) B16/F10 mouse melanoma cells known to express melanocortin receptors bound to the microspheres; and 6) cells of nonmelanocyte origin (e.g., mammary cancer cells, small-cell lung cancer cells, fibroblasts) did not bind to the macromolecular conjugate. One exception was that human epidermal keratinocytes also expressed melanocortin receptors as determined by all the criteria established above for epidermal melanocytes. Thus, cell specific melanocortin receptors appear to be characteristic cell surface markers of epidermal melanocytes and keratinocytes.     

Differential Regulation of Malate Dehydrogenase Isoenzymes by Hydrocortisone in the Liver and Brain of Aging Rats

The activities and induction patterns of the isoenzymes of malate dehydrogenase (MDH) of the liver and brain of male rats of various ages were studied. The activities of both the isoenzymes of MDH of the liver and brain show a gradual increase with increasing age of the rats. Adrenalectomy decreases and hydrocortisone treatment increases the activity of cytoplasmic MDH of the liver and brain of rats of all the ages except that of the brain isoenzyme of old rats. This hormone-mediated induction of the isoenzyme is actinomycin D-sensitive. Furthermore, adrenalectomy decreases and hydrocortisone treatment increases the activity of mitochondrial MDH of the liver of young and adult rats but not in old rats. However, these treatments do not show any significant effect on the activity of mitochondrial MDH of the brain of rats of all the ages.     

Reduced caloric intake and periodic fasting independently contribute to metabolic effects of caloric restriction

Caloric restriction (CR) has positive effects on health and longevity. CR in mammals implements time‐restricted (TR) feeding, a short period of feeding followed by prolonged fasting. Periodic fasting, in the form of TR or mealtime, improves metabolism without reduction in caloric intake. In order to understand the relative contribution of reduced food intake and periodic fasting to the health benefits of CR, we compared physiological and metabolic changes induced by CR and TR (without reduced food intake) in mice. CR significantly reduced blood glucose and insulin around the clock, improved glucose tolerance, and increased insulin sensitivity (IS). TR reduced blood insulin and increased insulin sensitivity, but in contrast to CR, TR did not improve glucose homeostasis. Liver expression of circadian clock genes was affected by both diets while the mRNA expression of glucose metabolism genes was significantly induced by CR, and not by TR, which is in agreement with the minor effect of TR on glucose metabolism. Thus, periodic fasting contributes to some metabolic benefits of CR, but TR is metabolically different from CR. This difference might contribute to differential effects of CR and TR on longevity.     

Chemically characterised Artemisia nilagirica (Clarke) Pamp. essential oil as a safe plant-based preservative and shelf-life enhancer of millets against fungal and aflatoxin contamination and lipid peroxidation

Abstract

The study recommends the Artemisia nilagirica (Clarke) Pamp. essential oil (ANEO) as plant-based shelf-life enhancer of millets against fungal, aflatoxin B₁ (AFB₁) contamination and lipid peroxidation with favourable safety profile. Chemical characterisation of ANEO through GC-MS, recorded 1,5-heptadiene-4-one,3,3,6-trimethyl (32.72%)as the main compound, followed by Artemisia alcohol (13.40%), alpha lonone (4.55%), benzene, methyl (1-methylethyl) (2.97%) and 1-cyclohexene-1-carboxaldehyde,4-(1-methylethyenyl) (2.23%). The mycoflora analysis of millet samples showed Aspergillus flavus strain[LHP(R)-5] as the most AFB₁ secreting strain. The ANEO inhibited growth and AFB₁ production by the toxigenic strain at 1.4 and 1.0?µL?mL^?1, respectively, and also possess broad fungitoxic spectrum. The decrement in membrane ergosterol content, enhanced leakage of cellular Ca²⁺, K⁺ and Mg²⁺ ions along with SEM and TEM study of ANEO-treated cell denotes plasma membrane as antifungal site of action. The ANEO also showed strong antioxidant activity as determined by DPPH^? and ABTS^?+ assays having IC₅₀ value 2.51 and 1.07?µL?mL^?1, respectively. More than 70.78% protection of Ragi samples from fungal contamination was observed during in situ trial. The ANEO showed favourable safety profile with high LD₅₀ value (7528.10?µL?kg^?1) for male mice and also exhibited non-phytotoxicity for Ragi seeds germination.