Adhesive apparatus in certain Indian hill stream fishes

The results of a detailed study on the adhesive apparatus of Indian hill stream cyprinid and sisorid fishes are presented. The structure of the mental suctorial disc in the genus Garra is described. Histological study of the mental region of Crossocheilus and Psilorhynchus has also been made and compared with the mental disc of Garra . The muscles of the disc which control its movements in bringing a partial vacuum during adhesion have been investigated. The complexity of the geniohyoideus muscles in Garra is interesting. Variations in the degree of development and histological modifications of the mental disc are exhibited by the fishes of the genus Garra .
A thoracic adhesive apparatus in the form of longitudinal or transverse ridges and grooves is present in the sisorids, Laguvia, Glyptothorax and Pseudecheneis except Gagata . A close study has revealed that the adhesive apparatus of the catfishes works mainly on the principle of friction. The variations in shape, size and location of the adhesive apparatus in various species are correlated to their respective habitats.
Structural variation in the adhesive apparatus of Pseudecheneis is maximum in comparison to that in Laguvia and Glyptothorax . It is discovered that the modifications are associated with the presence of multi-spinous layers, formation of caps by the basal or holdfast cells and with the transformation of loose areolar tissue into thick collagenous dermis. The presence of a pad of adipose tissue in the region of the adhesive apparatus has been reported and its physiological significance as a source of stored food suggested.
The anterior part of the protractor ischii muscle is modified to control the action of the adhesive apparatus. In Pseudecheneis , besides the m. protractor ischii, the ventral part of m. mesioventral is also associated with the adhesive apparatus.     

Kinetics of serotonin in platelets in essential hypertension.

In a study of the kinetics of 5-hydroxytryptamine (5-HT) in platelets in 26 hypertensive subjects with a mean systolic and diastolic blood pressure of 153.9 +/- 26.9 and 106.9 +/- 9.1 mm Hg respectively, it has been observed that in hypertensive platelets there was a marked decrease in 5-HT uptake and content, an increase in 5-HT efflux and an accompanying increase in Plasma 5-HT and 5-HIAA levels. Regression analysis of the data indicated a significant correlation between rise in diastolic blood pressure and these changes in 5-HT kinetics.     

Critical appraisal of fine needle aspiration cytology in tuberculous lymphadenitis.

A cytomorphologic diagnosis of tuberculous lymphadenitis by examination of needle aspirates was made in 560 of 1,471 cases of lymphadenopathy studied over two years. Cytologic features were categorized into four groups: epithelioid clusters with or without Langhans's giant cells without necrosis (32.14%), epithelioid clusters with or without Langhans's giant cells with necrosis (50.35%), occasional epithelioid cells without characteristic necrosis/giant cells (2.85%) and necrosis without epithelioid clusters or Langhans's giant cells (14.64%). While a diagnosis of tuberculous lymphadenitis was offered with confidence in the first two groups, constituting about 82.49% cases, aspirates from the third- and fourth-group patients were subjected to Ziehl-Neelsen staining for acid-fast bacilli, which was positive in 12.5% and 75.6% of cases, respectively.     

Purification and characterization of wheat and pine small basic protein substrates for plant calcium-dependent protein kinase.

A wheat basic protein (WBP) was purified to homogeneity from wheat germ by a protocol involving extraction, centrifugation, batchwise elution from carboxymethylcellulose (CM-52), acidification with trifluoroacetic acid, neutralization and HPLC on a SP5PW cation exchange column. WBP is a 10 kDa protein and is phosphorylated on serine residues by wheat germ Ca(2+)-dependent protein kinase (CDPK). [32P]phosphoWBP exactly comigrates with WBP on SDS-PAGE. WBP does not inhibit either wheat germ CDPK or calmodulin-dependent myosin light chain kinase. Apart from histone H1, WBP is the best endogenous substrate yet found for wheat embryo CDPK. A 12 kDa pine basic protein (PBP) was purified to homogeneity from seeds of stone pine (Pinus pinea L.) by a simple procedure involving batchwise elution from carboxymethylcellulose and cation exchange HPLC. PBP is also a good substrate for CDPK and is phosphorylated on Ser residues. N-terminal sequencing of WBP and PBP revealed that these proteins are homologous to a family of small basic plant proteins having a phospholipid transfer function.     

Role of Ca2+ in induction and secretion of dengue virus-induced cytokines

The present study was undertaken to investigate the role of calcium ions (Ca₂₊) in the induction and secretion of the dengue type 2 virus induced cytotoxic factor and the cytotoxin. This was done by using calcium channel blocking drugs such as verapamil, nifedipine or diltiazem hydrochloride. The production of cytotoxic factor was significantly reduced by treatment of dengue type 2 virus infected mice with verapamil. Similarly, a dosedependent inhibition of the secretion of cytotoxic factor was observed, when spleen cells of the virus-primed mice were treatedin vitro with the 3 calcium channel blockers. The production of cytotoxin by macrophages was abrogated by pretreatment with calcium channel blockers but had little effect on its secretion as shown by treatment of macrophages with verapamil at 1 h after the induction to later periods up to 18 h. The findings thus show that in the induction of both the cytokines Ca₂₊ plays a critical role; on the other hand it is required for the secretion of the cytotoxic factor but not for that of the cytotoxin.     

Synergistic interaction between particular X-chromosome deletions andSex-lethal causes female lethality inDrosophila melanogaster

We studied the effect on female viability oftrans-heterozygous combinations of X-chromosome deficiencies andSxl ^f1, a null allele ofSex-lethal. Twentyfive deficiencies, which together covered 80% of the X chromosome, were tested. Seven of thesetrans-hcterozygous combinations caused significant levels of female lethality. Two of the seven interacting deficiencies include the previously known sex determination genessans fills andsisterless-a. Four of the remaining uncover X-chromosomal regions that were not hitherto known to contain sex determination genes. These newly identified regions are defined by deficienciesDf(1)RA2 (7D10; 8A4-5),DJ(1)KA14 (7F1-2; 8C6),Df(1)C52 (8E; 9C-D) andDf(1)NI9 (17A1; 18A2). These four deficiencies were characterized further to determine whether it was the maternal or zygotic dosage that was primarily responsible for the observed lethality of female embryos,daughterless andextra macrochaetae, two known regulators ofSxl, influence the interaction of these deficiencies withSxl.     

Molecular Cloning and Characterization of a Calmodulin Gene from Arabidopsis thaliana

The calcium binding protein, calmodulin Is involved in regulating various cellular and biochemical processes. A gene tor calmodulin (CaM) has been Isolated from a genomic library of Arabidopsis thaliana constructed in ; EMBL-4 using a heterologous cDNA probe from electric eel. One of the positive clones was characterized and the region containing the calmodulin gene sequences was Identified, excised using appropriate restriction enzymes and subcloned Into a plasmid vector. The genomic clone contains a complete copy of the calmodulin gene. A comparison of the nucleotide sequence of the part of the clone with those of the other plant and animal systems confirms that the clone In fact contains the calmodulin gene sequences. Southern hybridization ulling the calmodulin gene sequences as a probe reveals the presence of more than one copy of the calmodulin gene. The results of this investigation taken together with those Iff the other. indicate that the calmodulin gene belongs to a small mutigene family consisting of atieast four member. In the Arabidopsis genome.