An analysis of the role of actin during pollen activation leading to germination in pear (Pyrus communis L.): treatment with cytochalasin D

Summary Major stages of actin organization during activation leading to germination of pear (Pyrus communis L.) pollen were disrupted by treatment with 5 g/ml cytochalasin D (CD), and the effects of the drug were monitored with rhodamine-phalloidin staining. CD induced the formation of granules or short rods in the place of the filamentous arrays that occur in normally developing pollen. Filamentous arrays, however, returned upon removal of CD. Pollen incubated directly in CD showed a gradual disappearance of circular actin profiles and their replacement by either granules or, less frequently, short rods. These granules and rods initially had a random distribution in the cell, but with time in CD they became localized at one of the three germination apertures. Pollen was also allowed to reach three stages of microfilament (MF) organization (initial fibrillar arrays, interapertural MFs, and MFs confined beneath a single aperture) prior to being continously exposed to CD. After CD treatment, germination was blocked and the number of cells containing short rods increased, but movement of actin to a single aperture continued. Finally, when pollen at different stages of MF organization was treated with a CD pulse and then transferred to drug-free medium, germination was delayed regardless of the stage of MF organization at the time of treatment. The results indicate that an uninterrupted progression of actin organization is essential for pollen germination, but that movement of actin in the cell is CD-insensitive.     

Prenatal intestinal histology and histochemistry in the goat

The mucosa of the small and large intestine of goat fetuses exhibited villi which had disappeared after the 32.5-cm curved crown rump (CVR) stage. At places, the stratified epithelial lining persisted among the normal columnar epithelium with goblet cells. The concentration of goblet cells increased with age, while the thickness of the epithelium decreased. The crypts of Lieberkühn were tortuous at the base. Brunner's glands appeared at the 14.2-cm CVR stage. Peyer's patches appeared at the 24.5-cm CVR stage in the ileum. The muscularis mucosae differentiated in the large intestine in group II (16.2- to 24.5-cm CVR length) and progressed caudocranially. The striated border of the intestinal epithelium presented with alkaline phosphatase activity; this border and the goblet cells also stained for mucin. Glycogen was demonstrable in the epithelium with greater concentrations in the duodenum and jejunum in group I (11.5- to 14.6-cm CVR length), and in the ileum and large intestine in group III (30.8- to 39.5-cm CVR length).     

Heavy metal (Pb) accumulation in metallophytes as influenced by the variations in rhizospheric and non-rhizospheric soils physico-chemical characteristics

Activities at root-soil interface determine the solubility and uptake of metals by plants. Metal accumulation in plant species (Imperata cylindrical, Cynodon dactylon, Eleucine indica, Gomphrena celosoides, Sporobolus pyramidalis, Chromolaena odorata and Rhynchospora corymbosa) growing on Pb contaminated site as influenced by variations in physico-chemical characteristics, dissolved organic matter (DOM), Pb fractionation and different functional groups (using Fourier Transmittance Infra-red) of rhizospheric and non-rhizospheric soils was assessed. The electrical conductivity (2660–5520 µs) and Pb concentrations (51390.0–64080.0 mg/kg) were more in non-rhizospheric than rhizospheric soils having 276 µs to 3160 µs EC and 3289.0 to 44850.0 mg/kg Pb. More nutrients, DOM and carbohydrates functional groups (C-O; 1100 -1000 and O-H; 3700–3600) were found in rhizospheric compared to non-rhizospheric soils. The pH was slightly acidic (5.0–5.54) and E. indica with the lowest pH (5.0) accumulated highest Pb concentrations in shoot (8030 mg/kg) and root (16380 mg/kg) while C. odorata with highest values of pH, P, Ca and Mg in rhizospheric soil accumulated the least (root; 331.6 and shoot: 209.0 mg/kg). Pb was more in organic and residual fractions of rhizospheric and non-rhizospheric soils respectively. Reduction in pH, EC coupled with nutrients and DOM availability increased Pb uptake by plants.     

Synthesis and Antiproliferative Activity of Hybrid Peptides for Ovarian and Prostate Cancer

International Journal of Peptide Research and Therapeutics - Ovarian carcinoma is the leading malignancy of the female congenital system with a high mortality rate. In ovarian carcinoma,...     

On the Morphology and Life-history of a New Species of Chroococcidiopsis Geitler (Chroococcales)

Summary Morphology and reproduction of Chroococcidiopsis mysorensis sp. nov., isolated from enrichment cultures of paddy field soils of Naganahalli (India), have been described. The taxonomic status of the genus Chroococcidiopsis has been discussed suggesting it to be placed under the order Chroococcales.     

Effect of foliar application of herbicides,Benthiocarb, 2,4-D and Fluchloralin on phyllosphere microflora of potato

Three herbicides, Benthiocarb, 2,4-D and Fluchloralin were evaluated for their effect on leaf surface microflora of potato. In general, the application of herbicides resulted into a drop in the microbial population. Throughout the study herbicide treated leaves harboured less population compared to the untreated ones.     

Quantum mechanical studies on the activity of anticancerous drug — Ellipticine

Ellipticine compounds, derivatives of pyrido-(4-3b) carbazole are used in the human cancer therapy. Most of these drugs interact directly with DNA molecule. CNDO method, alongwith second order perturbation theory and multicentered-multipole approxiation have been used to compute intermolecular interaction energies of ellipticine with DNA ase pairs (GC and AT) in both normal and inverted cases. An attempt has been made to correlate the drug-nucleic acid interactions for ellipticine to locate site of drug action and binding pattern on the basis of intermolecular forces