Systematics, biology, ecology And zoogeography of holothurians: Some observations on the biology of the holothurian Holothuria (metriatyla) scabra (Jaeger)

Some aspects on the biology of commercially most important holothuriam Holothuria (Metriatyla) acabra are presented. It subsists on the organic matter present in the mud or sand. An analysis of gut content revealed fine mud (75-125 ^), sand particles (250-500 p.), moUuscan shells, debris and bits of algae. This species spawns in June and October. By external examination and by taking sections of the gonads, five maturity stages such as immature, maturing, early mature, late mature and spent have been fixed. The characteristics of different stages of maturity are presented in detail

Size and weight reduction in Holothuria scabra processed as beche-de-mer

Growing demand for beche-de-mer in the marine export market has naturally led to considerable debate among fishery biologists in our country on the problem of irrational exploitation of the natural stock. Along the Tamil Nadu coast Holothuria scabra is fished for beche-de-mer preparation. Studies on the size at first maturity indicated that the spawning size is 201-230 mm and this size group after processing attains a reduced size of 73-80 mm. Revival of the natural stock can take place and this would help in encountering specimens beyond the size of 75 mm in length. More studies are required on the biology of Holothurians to determine precisely the period of maturity and spawning in different species in a year and it is advisable to observe a 'closed season' each year to conserve the holothurian resources

On Weakly Symmetric and Weakly Conformally Symmetric Spaces Admitting Veblen Identities

In the present paper some properties involving curvature tensor,conformal curvature tensor, Ricci tensor and scalar curvature, on weakly symmetric, weakly conformally symmetric and pseudo symmetric spaces are obtained

Studies on the Biology, Ecology and Fishery of the sea cucumber Holothuria (Metriatyla) scabra (Jaeger) from southeast coast of India, embodies

Among the echinoderms, holothurians are commercially imnortant. Certain species of holothurians are processed and the processed material is known as Beche-de-mer or Trepang in trade parlance. Beche-de-mer is considered a Chinese delicacy. At present, Indie is earning a foreign exchange of more than one crore rupees by exporting Beche-de-mer . This product has no internal market. It has been introduced by the Chinese and is in existence in the Gulf of Manner and Palk Bay for more than one thousand years. It has high nutritive value and also considered to have certain medicinal properties. The main international markets are Hongkong, Singapore and Malaysia

LACHESIS restricts gametic cell fate in the female gametophyte of Arabidopsis

In flowering plants, the egg and sperm cells form within haploid gametophytes. The female gametophyte of Arabidopsis consists of two gametic cells, the egg cell and the central cell, which are flanked by five accessory cells. Both gametic and accessory cells are vital for fertilization; however, the mechanisms that underlie the formation of accessory versus gametic cell fate are unknown. In a screen for regulators of egg cell fate, we isolated the lachesis (lis) mutant which forms supernumerary egg cells. In lis mutants, accessory cells differentiate gametic cell fate, indicating that LIS is involved in a mechanism that prevents accessory cells from adopting gametic cell fate. The temporal and spatial pattern of LIS expression suggests that this mechanism is generated in gametic cells. LIS is homologous to the yeast splicing factor PRP4, indicating that components of the splice apparatus participate in cell fate decisions

Increased yield of smear positive pulmonary TB cases by screening patients with >2 weeks cough, compared to >3 weeks and adequacy of 2 sputum smear examinations for diagnosis

Background RNTCP recommends examining three sputum smears for AFB from Chest Symptomatics (CSs) with cough of >3 weeks for diagnosis of Pulmonary TB (PTB). A previous multi-centric study from Tuberculosis Research centre (TRC) has shown that the yield of sputum positive cases can be increased if duration of cough for screening was reduced to >2 weeks. Other studies have shown that two smear examinations are adequate for diagnosis of smear positive PTB . To validate the above findings, a cross sectional multi-centric study was repeated in different settings in five geographical areas in India. Methods Three primary and secondary level health facilities with high out-patient attendance were selected from two Tuberculosis Units (TU) in each of the 15 selected districts to screen about 10,000 new adult outpatients from each state. For patients who did not volunteer history of cough, symptoms were elicited using a structured simple questionnaire. All the CSs were referred for sputum examination. Results A total of 96,787 out-patients were registered. Among them 69,209 (72%) were new adult out-patients. Using >2 weeks of cough instead of > 3 weeks as the criterion for screening, there was an overall increase of 58% in CS and 23% increase in the detection of smear-positive cases. Among 211 patients, 210 were positive at least by one smear from the initial two specimens. Increase in the work-load if 2 smears were done for patients with cough of >2 weeks cough were 2 specimens (i.e.13 to 15) per day for an adult OPD of 150. Conclusion The yield of sputum positive PTB cases can be improved by screening patients with >2 weeks cough and two specimens are adequate for diagnosis

Design Development and Evaluation of Cefixime Solid Lipid Nanoparticles for Enhancement of Oral Bioavailability

Solid Lipid Nanoparticles (SLNs) of Cefixime were prepared by hot homogenization and ultrasound dispersion method using glyceryl monostearate (GMS) as the lipid. Particle size and zeta potential of Cefixime loaded SLN was measured using a Malvern Zetasizer 3000 Nano ZS (Malvern instruments) SLN dispersion prepared using Poloxamer 188 2.0% as stabilizer (F4, F5 and F6) showed lower particle size than the other surfactants. The entrapment efficiency (EE) of SLN dispersion was determined by the centrifugation method. Among the various surfactants used Poloxamer 188 shows highest drug entrapment. The invitro drug release study was determined using USP Type II apparatus paddle in phosphate saline buffer pH7.2. The drug release of F6 formulation at the end of 5 hrs was about 94.71±0.53%. The morphology of Cefixime loaded SLN dispersion was examined by scanning electron microscope. The above observation shows that Cefixime absorption is enhanced by using solid lipid nanoparticles formulations

Wnt5a induces ROR1 to complex with HS1 to enhance migration of chronic lymphocytic leukemia cells.

ROR1 (receptor tyrosine kinase-like orphan receptor 1) is a conserved, oncoembryonic surface antigen expressed in chronic lymphocytic leukemia (CLL). We found that ROR1 associates with hematopoietic-lineage-cell-specific protein 1 (HS1) in freshly isolated CLL cells or in CLL cells cultured with exogenous Wnt5a. Wnt5a also induced HS1 tyrosine phosphorylation, recruitment of ARHGEF1, activation of RhoA and enhanced chemokine-directed migration; such effects could be inhibited by cirmtuzumab, a humanized anti-ROR1 mAb. We generated truncated forms of ROR1 and found its extracellular cysteine-rich domain or kringle domain was necessary for Wnt5a-induced HS1 phosphorylation. Moreover, the cytoplamic, and more specifically the proline-rich domain (PRD), of ROR1 was required for it to associate with HS1 and allow for F-actin polymerization in response to Wnt5a. Accordingly, we introduced single amino acid substitutions of proline (P) to alanine (A) in the ROR1 PRD at positions 784, 808, 826, 841 or 850 in potential SH3-binding motifs. In contrast to wild-type ROR1, or other ROR1P→︀A mutants, ROR1P(841)A had impaired capacity to recruit HS1 and ARHGEF1 to ROR1 in response to Wnt5a. Moreover, Wnt5a could not induce cells expressing ROR1P(841)A to phosphorylate HS1 or activate ARHGEF1, and was unable to enhance CLL-cell motility. Collectively, these studies indicate HS1 plays an important role in ROR1-dependent Wnt5a-enhanced chemokine-directed leukemia-cell migration

Electrochemical behaviour of some alkyl substituted N-hydroxy-2,6-diarylpiperidin-4-one thiosemicarbazone and the antifungal studies of the products

A series of 3-ethyl-2,6-diarylpiperidin-4-one thiosemicarbazone and 3,5-dimethyl-2,6-diarylpiperidin-4-one thiosemicarbazone were synthesised. The thiosemicarbazones were subjected to cyclic voltammetric study using graphite electrode with variable scan rate at moderate acidic conditions maintained in the electrolytic solution. The reduction takes place by two electron transfer and the reaction is pH dependent. The reduced products were isolated and purified by column chromatography. The structure was proved by 1H and 13C NMR spectroscopy. The electrode process was found to be irreversible and diffusion controlled. Further the products were analysed for anti fungal activity in which nitro substituted compound showed high inhibition towards the fungi Asperillus nige

Studies on the biology, ecology and fishery of the sea cucumber Holothuria (Metriatyla) scabra (Jaeger) from south east coast of India

Among the echinoderms, holothurians (also known as 'Sea cucumbers) are commercially important. Introduced by the Chinese, they are in existence in the Gulf of Mannar and Palk Bay for more than one thousand years