Immunogenicity of human spermatozoa

Investigation and experimental design of the study was basically aimed at developing insight into the antigenicity of spermatozoa-associated proteins. Apart from studying the natural antigenicity of washed whole spermatozoa, their immunogenicity was also demonstrated _in vitro_. The whole live spermatozoa were immobilized and agglutinated _in vitro_ by the antibodies they induced in the laboratory model - a female rabbit. A regular immunization routine induced a high titre of antisperm polyclonal antibodies. To prepare a spermatozoa specific antigen which will not produce a cross-reacting antibody against other human tissues, only the motile and live spermatozoa were selected for antigen preparation. In investigation the laboratory-bred female rabbits were used as the bioactive system of production of antisperm antibody. Agglutination of whole spermatozoa has been observed on slides. The technique though simple is highly eloquent; clumping of spermatozoa confirms the existence of antisperm antibodies in the serum under examination. The results show that nature and pattern of immobilization of active motile spermatozoa are different as observed in different graphs of immobilization. The variation in spermatozoal population in antigen distribution on individual spermatozoa is reflected in different patterns of agglutination

Opposite Root Growth Phenotypes of hy5 versus hy5 hyh Mutants Correlate with Increased Constitutive Auxin Signaling

The Arabidopsis transcription factor HY5 controls light-induced gene expression downstream of photoreceptors and plays an important role in the switch of seedling shoots from dark-adapted to light-adapted development. In addition, HY5 has been implicated in plant hormone signaling, accounting for the accelerated root system growth phenotype of hy5 mutants. Mutants in the close HY5 homolog HYH resemble wild-type, despite the largely similar expression patterns and levels of HY5 and HYH, and the functional equivalence of the respective proteins. Moreover, the relative contribution of HYH to the overall activity of the gene pair is increased by an alternative HYH transcript, which encodes a stabilized protein. Consistent with the enhanced root system growth observed in hy5 loss-of-function mutants, constitutively overexpressed alternative HYH inhibits root system growth. Paradoxically, however, in double mutants carrying hy5 and hyh null alleles, the hy5 root growth phenotype is suppressed rather than enhanced. Even more surprisingly, compared to wild-type, root system growth is diminished in hy5 hyh double mutants. In addition, the double mutants display novel shoot phenotypes that are absent from either single mutant. These include cotyledon fusions and defective vasculature, which are typical for mutants in genes involved in the transcriptional response to the plant hormone auxin. Indeed, many auxin-responsive and auxin signaling genes are misexpressed in hy5 mutants, and at a higher number and magnitude in hy5 hyh mutants. Therefore, auxin-induced transcription is constitutively activated at different levels in the two mutant backgrounds. Our data support the hypothesis that the opposite root system phenotypes of hy5 single and hy5 hyh double mutants represent the morphological response to a quantitative gradient in the same molecular process, that is gradually increased constitutive auxin signaling. The data also suggest that HY5 and HYH are important negative regulators of auxin signaling amplitude in embryogenesis and seedling development

Effect of high arsenic content in drinking water on rat brain

51-54The permissible limit of arsenic content in drinking water is 0.05 ppm, whereas, in many parts of West Bengal the arsenic level in drinking water is 0.1 ppm, frequently 0.3 ppm and even 3.0 ppm, though rarely. In order to assess possible risk to brain function by drinking such water, rats were given arsenic mixed in drinking water at the above four concentrations for 40 days. There was increased lipid peroxidation at all doses of arsenic, including the 'permissible limit', decrease in glutathione level, superoxide dismutase and glutathione reductase activities, indicating the free-radical-mediated degeneration of brain.</span

Secret Image Sharing Schemes: A Comprehensive Survey

The safeguarding of digitized data against unwanted access and modification has become an issue of utmost importance as a direct result of the rapid development of network technology and internet applications. In response to this challenge, numerous secret image sharing (SIS) schemes have been developed. SIS is a method for protecting sensitive digital images from unauthorized access and alteration. The secret image is fragmented into a large number of arbitrary shares, each of which is designed to prevent the disclosure of any information to the trespassers. In this paper, we present a comprehensive survey of SIS schemes along with their pros and cons. We review various existing verifiable secret image sharing (VSIS) schemes that are immune to different types of cheating. We have identified various aspects of developing secure and efficient SIS schemes. In addition to that, a comparison and contrast of several SIS methodologies based on various properties is included in this survey work. We also highlight some of the applications based on SIS. Finally, we present open challenges and future directions in the field of SIS

Evidence of calcium influx across the plasma membrane depends upon the initial rise of cytosolic calcium with activation of IP<SUB>3</SUB> in rat enterocytes by heat-stable enterotoxin of Vibrio cholerae non-O1

In response to heat-stable enterotoxin of Vibrio cholerae non-O1, the initial rise of cytosolic Ca2+ occurred with activation of IP3. Chelation of extracellular Ca2+ with EGTA and suspension of cells in Ca2+ free buffer both demonstrated the involvement of internal stores in the rise of [Ca2+]i. Cells pretreated with dantrolene resulted in decrease of [Ca2+]i response which suggested that the rise of intracellular level of Ca2+ was mostly due to the mobilization from IP3 sensitive stores. When the cytosolic Ca2+ was chelated by loading the cells with BAPTA, NAG-ST could not induce Ca2+ entry to the cell as assessed by Mn2+ quenching of fura-2 fluorescence which suggested that calcium influx across the plasma membrane depends upon initial rise of this bivalent cation that maintained the sustained phase of [Ca2+]i response. Addition of toxin to the fura-2-loaded cells, preincubated with lanthanum chloride, resulted in reduction of [Ca2+]i level with a short duration of irregular sustained phase further suggesting that the influx of Ca2+ across the plasma membrane might be through the calcium channel