Trisomy 18q: 46,XX,-10,+der(10) t(10;18) (p15;q12) pat: a case report.

A 2-month-old female with intrauterine and postnatal growth retardation, multiple congenital anomalies, absent right kidney, congenital heart disease was investigated. Her karyotype revealed, 46,XX,-10,+der(10), t(10;18) (p15;q12) pat. The child died at 2 months 2 weeks. This is the third case of trisomy 18q resulting from translocation of chromosome 10 and 18.     

Efficient transgenic plant regeneration throughAgrobacterium-mediated transformation of Chickpea (Cicer arietinum L.)

Three genotypes of chickpea ICCV-1, ICCV-6 and a Desi (local) variety were tested for plant regeneration through multiple shoot production. The embryo axis was removed from mature seeds, the root meristem and the shoot apex were discarded. These explants were cultured on medium containing MS macro salts, 4X MS micro salts, I35 vitamins, 3.0 mg/1 BAP, 0.004 mg/1 NAA, 3% (w/v) sucrose and incubated at 26⁰C. The explants were transformed withAgrobacterium tumefaciens strain LBA4404 with binary vector pBI121 containing theuidA andnptIl genes. Multiple shoots were repeatedly selected with kanamycin. The selected kanamycin resistant shoots were rooted on MS medium supplemented with 0.05 mg/1 113A. The presumptive transformants histochemically stained positive for GUS. Additionally, nptll assay confirmed the expression ofnptII in kanamycin resistant plants. Transgenic plants were transferred to soil and grown in the green house.Abbreviations BAP 6-benzylamino purine - 2,4-D 2,4dichlorophenoxy acetic acid - IAA Indole acetic acid - IBA Indole butaric acid - NAA Naphthalene acetic acid     

Biodegradation of phenol by arthrobacter and modelling of the kinetics

The toxic effects of phenol, a common constituent of many industrial effluents, necessitates treatment of the polluted streams. Biodegradation is a popular technique and enjoys many advantages. The degradation of phenol with Arthrobacter species is studied in batch cultures and it is observed that the substrate is inhibiting. The fit of various models, including the model proposed earlier by us [17], to the experimental data is studied. The model is used to fit available data in literature, which unfortunately is very sparse. In all the cases the present model fits the data best.List of Symbols S mg/l substrate concentration - S ₀ mg/l threshold substrate concentration - K _I mg/l inhibition constant - K _m , K _s mg/l half saturation constant of growth kinetics - m, n constants - 1/h specific growth rate - _m 1/h maximal specific growth rate - X mg/l biomass concentration at time t - X ₀ mg/l initial biomass concentration Abbreviations MTCC Microbial Type Culture Collection - IMTECH Institute of Microbial Technology The cooperation of the staff of the Biosciences and Biotechnology Center, I.I.T. Madras is greatly appreciated.     

Increased plasma corticosterone levels in bovine growth hormone (bGH) transgenic mice: Effects of ACTH,GH and IGF-I onin vitro adrenal corticosterone production

Previous work from our laboratory provided evidence for increased plasma corticosterone levels in mice transgenic for human and bovine growth hormone (GH). Corticosterone was elevated in both sexes, under both basal and ether-induced stress conditions. The objectives of the present study were to investigate thein vitro adrenal sensitivity to ACTH, GH and/or IGF-I in normal and bGH transgenic mice, to examine plasma corticosterone levels at different times of the day, and to determine plasma levels of ACTH in these animals. For the measurement of plasma corticosterone and ACTH levels, transgenic and normal siblings were housed 2 per cage and decapitated simultaneously within 20 seconds of the first disturbance of the cage. The corticosterone production byin vitro adrenal incubations did not differ between adrenals from normal and transgenic mice at the basal level or in the presence of different doses of ACTH. Growth hormone or IGF-I did not have any effect on corticosterone productionin vitro when given alone, and did not modify the effects of ACTH on the accumulation of corticosterone in the media. Plasma corticosterone concentrations were higher in transgenic than in normal animals in both morning and evening. Plasma concentrations of ACTH in animals killed in the morning were sharply increased in transgenic males as compared with their normal siblings. The results indicate that increased circulating levels of corticosterone in transgenic mice are not due to a potentiation of ACTH actions by GH or IGF-I, but rather to a chronic increase in plasma ACTH levels. The increase in ACTH is presumably a reflection of GH actions in the hypothalamic-pituitary system.     

Oligomerization of the hydrophobic heptad repeat of gp41.

The transmembrane protein of human immunodeficiency virus type 1 (HIV-1) contains a leucine zipper-like (hydrophobic heptad) repeat which has been predicted to form an amphipathic alpha helix. To evaluate the potential of the hydrophobic heptad repeat to induce protein oligomerization, this region of gp41 has been cloned into the bacterial expression vector pRIT2T. The resulting plasmid, pRIT3, expresses a fusion protein consisting of the Fc binding domain of monomeric protein A, a bacterial protein, and amino acids 538 to 593 of HIV-1 gp41. Gel filtration chromatography demonstrated the presence of oligomeric forms of the fusion protein, and analytical centrifugation studies confirmed that the chimeric protein formed a higher-order multimer that was greater than a dimer. Thus, we have identified a region of HIV-1 gp41 which is capable of directing the oligomerization of a fusion protein containing monomeric protein A. Point mutations, previously shown to inhibit the biological activity of the HIV-1 envelope glycoprotein, have been engineered into the segment of gp41 contained in the fusion protein, and expressed mutant proteins were purified and analyzed via fast protein liquid chromatography. A point mutation in the heptad repeat, which changed the central isoleucine to an alanine, caused a significant (> 60%) decrease in oligomerization, whereas changing the central isoleucine to aspartate or proline resulted in almost a complete loss of oligomerization. Deletions of one, two, or three amino acids following the first isoleucine also resulted in a profound decrease in oligomerization. The inhibitory effects of the mutations on oligomer formation correlated with the effects of the same mutations on envelope glycoprotein-mediated fusion. A possible role of the leucine zipper-like region in the fusion process and in an oligomerization event distinct from assembly of the envelope glycoprotein complex is discussed.     

Metabolism of activated oxygen in detached wheat and rye leaves and its relevance to the initiation of senescence

Pollen grains of Plumbago zeylanica L. were serially sectioned and examined using transmission electron microscopy to determine the three-dimensional organization of sperm cells within the microgametophyte and the quantity of membrane-bound organelles occurring within each cell. Sperm cells occur in pairs within each pollen grain, but are dimorphic, differing in size, morphology and organelle content. The larger of the two sperm cells (S_vn) is distinguished by the presence of a long (approx. 30 m) projection, which wraps around and lies within embayments of the vegetative nucleus. This cell contains numerous mitochondria, up to two plastids and, infrequently, microbodies. It is characterized by a larger volume and surface area and contains a larger nucleus than the other sperm cell. The second sperm cell (S_ua) is linked by plasmodesmata with the S_vn, but is unassociated with the vegetative nucleus. It is smaller and lacks a cellular projection. The S_ua contains relatively few mitochondria, but numerous (up to 46) plastids and more microbodies than the other sperm. The degree of dimorphism in their content of heritable cytoplasmic organelles must at fertilization result in nearly unidirectional transmission of sperm plastids into just one of the two female reproductive cells, and preferential transmission of sperm mitochondria into the other.Abbreviations S_ua sperm cell unassociated with the vegetative nucleus - S_vn sperm cell physically associated with the vegetative nucleus 1=Russell and Cass (1981)     

Sex-related differences in food and water intake and body weight changes with prolonged administration of adrenaline in the rat

Male and female rats were treated with different high doses of adrenaline for five days. Their food and water intakes and body weights were recorded. A considerable sex-difference was found on the 5th day in body weights and plasma glucose concentrations. Males had higher plasma glucose and lost more weight than females. Females ate and drank more than males throughout the experiment. The adrenaline-sensitivity of females decreased by the third day but it did not change in males. These data suggest that females are able to activate mechanisms that compensate the effects of high adrenaline levels while males are not, or their compensatory mechanisms are less efficient.     

Effect of long-term prostacyclin treatment on the gastric mucosa of rat

According to Bálint and Varró, oral administration of prostacyclin (PGI2) resulted in a significant increase of the DNA-content of the gastric mucosa within a short period of time. In the present study, there was no change in the protein content of the gastric mucosa after oral administration of 100 micrograms/kg/day of PGI2 for 80 days, while the DNA-content increased significantly. The RNA/DNA ratio decreased. Histologically a significant increase in the thickness of the gastric mucosa, as well as in the number of parietal and epithelial cells were found. The cell hyperplasia in the corpus mucosa was accompanied by a decreased number of G-cells of the antral mucosa. The increase of parietal cell number and the decrease of G-cell number after long term PGI2 administration might be explained by the divergent effect of treatment on the kinetics of the different cell types in the gastric mucosa.