Synthesis, structure and luminescence behaviour of a mononuclear cadmium(II) dicyanamide and a coordination polymer of mercury(II) dicyanamide containing 2,2′-dipyridylamine (dpaH) as end-capping ligand/anion of dpaH as binucleating bridge. Variance in coordination numbers, nuclearities and architectures with metal ion templates

A mononuclear compound [Cd(dpaH)₂(dca)₂] (1) and a tetranuclear based 2D coordination polymer [Hg₄(dpa)₄(dca)₄]_n (2) [dpaH = 2,2′-dipyridylamine, dpa = anion of dpaH, dca = dicyanamide] have been synthesized and characterized. X-ray structural analyses reveal that cadmium(II) center in 1 has a distorted octahedral geometry with a CdN₆ chromophore ligated through two bidentate neutral dpaH units along with two nitrile N atoms of two terminally bound dca units in mutual cis orientation. Each of the four independent mercury(II) centers in 2 adopts a distorted trigonal bipyramidal environment coordinated by two pyridine N atoms of two different anionic dpa ligands, two nitrile N atoms of two μ_1,5 bridged dca units and the fifth position is occupied by the amide N of one dpa. Cooperative intermolecular N-H···N and C-H···N hydrogen bondings promote dimensionality in 1. The compounds display intraligand ¹(π-π^∗) fluorescence in DMF solutions at room temperature.     

Pathogenic and non-pathogenic mycoflora in the air and phylloplane ofTriticum aestivum L

Aerobiological investigations were carried out over wheat (Triticum aestivum L.) fields near Barrackpore, West Bengal, India for two consecutive crop seasons. In 1990–91, except for the very seedling stage there was a more or less uniform spore count up to the maximum vegetative growth stage and from flowering onwards, a gradual increase in total cfus was observed with the peak (331 CFUs) during the harvesting stage. In the second season, similar results were recorded where peak spore load (2064 CFUs) in the air was during harvesting operation followed by a sudden decline in the empty field.Cladosporium spp. dominated both the seasons mainly up to February.Penicillium, Curvularia, Aspergillus andCephalosporium were the most frequent non-pathogenic fungal types. Among the pathogenic fungi,Alternaria andDrechslera were recorded to be the most virulent to wheat crop, after inflorescence to later stages in both the seasons causing heavy leaf damage producing necrotic spots during which peak cfus were found.Fusarium was frequently found showing the peak during vegetative growth period.Sclerotium was more common in the second season than in the first season. High occurrence ofNigrospora was recorded in the earlier stages. Sterile forms were found regularly. The phylloplane studies revealed thatCladosporium was the most dominant flora contributing 40–66% up to February in winter; gradually disappeared from the leaf surface with the onset of summer.Aspergillus andPenicillium showed the reverse picture. WhileCurvularia was isolated in high amount during later stages;Nigrospora mainly during the vegetative growth stages.Alternaria (caused Alternaria blight) andDrechslera were significantly isolated during harvesting (28.08%) and at late grain maturation stage (80.10%), respectively.Sclerotium and Sterile forms were recorded regularly unlikeFusarium andHelminthosporium.     

Pathogenic and non-pathogenic mycoflora in the air and phylloplane ofTriticum aestivum L.

Aerobiological investigations were carried out over wheat (Triticum aestivum L.) fields near Barrackpore, West Bengal, India for two consecutive crop seasons. In 1990–91, except for the very seedling stage there was a more or less uniform spore count up to the maximum vegetative growth state and from flowering onwards, a gradual increase in total cfus was observed with the peak (331 CFUs) during the harvesting stage. In the second season, similar results were recorded where peak spore load (2064 CFUs) in the air was during harvesting operation followed by a sudden decline in the empty field.Cladosporium spp. dominated both the seasons mainly up to February.Penicillium, Curvularia, Aspergillus andCephalosporium were the most frequent non-pathogenic fungal types. Among the pathogenic fungi,Alternaria andDrechslera were recorded to be the most virulent to wheat crop, after inflorescence to later stages in both the seasons causing heavy leaf damage producing necrotic spots during which peak cfus were found.Fusarium was frequently found showing the peak during vegetative growth period.Sclerotium was more common in the second season than in the first season. High occurrence ofnigrospora was recorded in the earlier stages. Sterile forms' were found regularly. The phylloplane studies revealed thatCladosporium was the most dominant flora contributing 40–66% up to February in winter; gradually disappeared from the leaf surface with the onset of summer.Aspergillus andPenicillium showed the reverse picture. WhileCurvularia was isolated in high amount during later stages;Nigrospora mainly during the vegetative growth stages.Alternaria (caused Alternaria blight) andDrechslera were significantly isolated during harvesting (28.08%)and at late ‘grain maturation’ stage (80.10%), respectively.Sclerotium and ‘Sterile forms’ were recorded regularly unlikeFusarium andHelminthosporium.     

Plant regeneration from alginate encapsulated somatic embryos of Asparagus cooperi baker

Somatic embryos of Asparagus cooperi were encapsulated as single embryos approximately 4–6 mm in diameter to produce individual synthetic seeds. The frequency of conversion of artificial seeds to plants was 34%. This frequency was affected by the concentration of calcium chloride, the commercial sources of sodium alginate, and the nutrient medium. The conversion frequency of artificial seeds to seedling plants was 8.3% after storage for 90 days at 2°C.Abbreviations NAA -Naphthaleneacetic acid - ABA Abscisic acid - GA₃ Gibberellic acid - Kn 6-Furfurylaminopurine - MS Murashige and Skoog (1962) medium - SH Schenk and Hildebrandt (1972) medium - WM White (1963) medium     

Airborne fungal load in agricultural environment during threshing operations

The effect of threshing operations on the fungal spora of farm air, has been studied with the culture plate method. Air samples were taken before, during and after the threshing of paddy and wheat grains, at the end of the respective crop seasons. An immediate local increase in the airborne fungal load was observed during threshing operations. In case of wheat the high rise was due toAlternaria tenuissima, followed byDrechslera sp. andCladosporium herbarum. In Boro variety of paddy, the high count was contributed byAlternaria humicola andA. tenuissima, while in Aman variety,Helminthosporium oryzae was the dominant type followed byC. herbarum and unidentified yeasts.Aspergillus spp. were observed in significant numbers before the operation started; their occurrence was negligible during threshing. A considerable number of yeast was observed, particularly during threshing and after threshing operations.     

Synergetic effects of TDZ with various phytohormones on high-frequency plant regeneration from mature nodal explants of Capparis decidua and their ex vivo implications

Plant Cell, Tissue and Organ Culture (PCTOC) - Capparis decidua (Forssk.) Edgew., is a well-known ornamental shrub of arid and semi-arid horticulture and agroforestry. This paper represents the...     

The nutritional and metabolic indices in rats fed cholesterol-containing diets supplemented with durian at different stages of ripening

The aim of this investigation was to assess the nutritional and health properties of Mon Thong durian cultivar at different stages of ripening. The assessment was carried out in vitro and in vivo. The contents of dietary fibers, minerals and trace metals at different stages of ripening were comparable. Total polyphenols (mgGAE/100 g FW) and flavonoids (mg CE/100 gFW) in ripe durian (358.8 +/- 31.4 and 95.4 +/- 9.3) were significantly higher (p < 0.05) than in mature (216.1 +/- 1 and 39.9 +/- 3.8) and overripe (283.3 +/- 26.2 and 53.5 +/- 4.9). Antioxidant capacity (muMTE/100 g FW) in total polyphenol extracts of ripe durian measured by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and [2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS) assays (259.4 +/- 23.6 and 2341.8 +/- 93.2) were significantly higher (p < 0.05) than that of mature (151.6 +/- 15.2 and 1394.6 +/- 41.5) and overripe (201.7 +/- 19.4 and 1812.2 +/- 61.4) samples. The correlation coefficients between the bioactive compounds in different stages of ripening and their antioxidant capacities were high (R;{2} = 0.99). Then 35 male Wistar rats were divided into 5 dietary groups each of 7 and named Control, Chol, Chol/Mature, Chol/Ripe and Chol/Overripe. During 30 days of the experiment the rats of all 5 groups were fed basal diet (BD), which included wheat starch, casein, soybean oil, vitamin and mineral mixtures. The rats of the Control group were fed a BD only. To the BD of the Chol group was added 1% of cholesterol. The BD of the Chol/Mature, Chol/Ripe and Chol/Overripe groups was supplemented with 1% of cholesterol and 5% of the mature, ripe and overripe durian as freeze-dried powder, respectively. Diets containing ripe and to a lesser degree mature and overripe durian significantly hindered the rise in plasma lipids and also hindered a decrease in plasma antioxidant activity. The nitrogen retention in rats of the Chol/Ripe group was significantly higher (63.6%, P < 0.05) than in other diet groups and the level of the plasma glucose remained normal. A decrease in fibrinogen fraction with ripe durian included in rat's diets was shown by electrophoretic separation. These changes were detected mostly in the low molecular weight proteins of rat's serum. Histological examination of aorta showed only slight differences in the tissue. In conclusion, ripe durian contains higher quantity of bioactive compounds, has higher antioxidant capacity and nutritional value. It positively affects the plasma lipid profile, the plasma glucose and the antioxidant activity in rats fed cholesterol enriched diets. Therefore, the ripe durian supplemented diet could be beneficial for patient suffering from hypercholesterolemia and diabetes mellitus. <     

Enhanced proliferation and migration of vascular smooth muscle cells in response to vascular injury under hyperglycemic conditions is controlled by β3 integrin signaling

Atheroma formation and restenosis following percutaneous vascular intervention involve the growth and migration of vascular smooth muscle cells (SMCs) into neointimal lesions, in part due to changes in the extracellular matrix. While some clinical studies have suggested that, in comparison to non-diabetics, β3 integrin inhibition in diabetic patients confers protection from restenosis, little is known regarding the role of β3 integrin inhibition on SMC responses in this context. To understand the molecular mechanisms underlying integrin-mediated regulation of SMC function in diabetes, we examined SMC responses in diabetic mice deficient in integrin β3 and observed that the integrin was required for enhanced proliferation, migration and extracellular regulated kinase (ERK) activation. Hyperglycemia-enhanced membrane recruitment and catalytic activity of PKCβ in an integrin β3-dependent manner. Hyperglycemia also promoted SMC filopodia formation and cell migration, both of which required αVβ3, PKCβ, and ERK activity. Furthermore, the integrin–kinase association was regulated by the αVβ3 integrin ligand thrombospondin and the integrin modulator Rap1 under conditions of hyperglycemia. These results suggest that there are differences in SMC responses to vascular injury depending on the presence or absence of hyperglycemia and that SMC response under hyperglycemic conditions is largely mediated through β3 integrin signaling.     

Efficacy of Butea monosperma on dermal wound healing in rats

Wound healing occurs as a fundamental response to tissue injury. Several natural products have been shown to accelerate the healing process. The present investigation was undertaken to determine the efficacy of topical administration of an alcoholic bark extract of Butea monosperma (B. monosperma) on cutaneous wound healing in rats. Full-thickness excision wounds were made on the back of rat and B. monosperma extract was administered topically. The granulation tissue formed on days 4, 8, 12 and 16 (post-wound) was used to estimate total collagen, hexosamine, protein, DNA and uronic acid. The extract increased cellular proliferation and collagen synthesis at the wound site, as evidenced by increase in DNA, total protein and total collagen content of granulation tissues. The extract treated wounds were found to heal much faster as indicated by improved rates of epithelialization and wound contraction, also confirmed by histopathological examinations. Also, the tensile strength of drug-treated wounds was increased significantly. In addition, we show that B. monosperma possesses antioxidant properties, by its ability to reduce lipid peroxidation. The results clearly substantiate the beneficial effects of the topical application of B. monosperma in the acceleration of wound healing.