Changes in the levels of pituitary and steroid hormones in ovine and human ovarian follicular fluid

Changes in the protein and steroid hormones of follicular fluid, aspirated from different follicles of sheep and human ovaries, have been measured and correlated with the size of the follicles. As the fluid contains a number of proteins, steroids have been measured directly and after ether extraction. The follicular fluid concentrations of progesterone and 17 beta-oestradiol measured directly in the fluid increased with the size of the follicles. The levels of free testosterone remained constant in all sizes of follicles, while those of bound hormone showed a 10- to 15-fold increase over the free testosterone concentrations in both the sheep and human follicular fluid. A decrease in the levels of bound testosterone in the fluid of large follicles (LFFL) coincided with the increase in bound 17 beta-oestradiol, suggesting the possible conversion of bound testosterone to oestrogen as the follicle attained maturity. The ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) varied in the fluid obtained from different size follicles, being 1:7 in small (SFFL), 1.3.5 in medium (MFFL) and 1:2.3 in large (LFFL) follicles of sheep ovaries. The LH content of follicular fluid of different size follicles appeared to be the same, with LFFL showing a minor increase over SFFL. In the human, the fluid from medium follicles contained very little LH compared to LFFL. These differences in the pattern of LH levels present in the fluid from different size follicles between human and sheep ovaries presumably reflect species variations in the entry of LH into the follicles.     

Incidence of actinomycetes infection in women using intrauterine contraceptive devices

Pancervicovaginal smears taken from 350 women using an intrauterine contraceptive device (IUD) were screened for the presence of actinomycetes organisms. Of the 12 cases in which actinomycetes-like organisms were seen in Papanicolaou-stained smears, the presence of actinomycetes organisms was confirmed by immunofluorescence in 10 cases. The prevalence of actinomycetes infection was thus 2.8% (10 of 350 cases) in the IUD users. Eight (4.3%) of 173 symptomatic subjects had actinomycetes infections. Two of the positive cases were asymptomatic. Eight of the ten patients with confirmed actinomycetes infection were using the Cu T device while two were wearing the Lippes Loop IUD. Seven of the ten patients had been using an IUD for more than two years. The time of insertion of the IUD (postpuerperal, postmenstrual or after medical termination of pregnancy) did not show any correlation with the presence of actinomycetes infection. Actinomyces israelii was responsible for the infection in eight cases while Arachnia propionica was seen in two cases. The organisms could not be grown in culture.     

Cloning of ODAP Degrading Gene and Its Expression as Fusion Protein in Escherichia coli

A gene responsible for the degradation of ß-N-Oxalyl diaminopropionic acid (ODAP) was fused to the maIE gene, which codes for maltose binding protein, by cloning into an expression vector pMAL c2. The gene has been expressed as fusion protein of mol wt approximately 62 kD. It has been purified by affinity chromatography. The fusion protein has been cleaved by an endoprotease factor Xa and the presence of maltose binding protein and the product of the cloned gene confirmed. SDS-PAGE has shown that the product of the ODAP degrading gene is a single polypeptide of mol wt of about 20.7 kD.     

Purification and Characterization of Lectin from Lathyrus sativus

Lectin has been isolated and purified from Lathyrus sativus using ammonium sulphate precipitation followed by affinity chromatography. The molecular weight as determined by HPLC was found to be 42kD. The lectin is a tetramer, consisting of two types of subunits of which the heavier subunit consists of 2 polypeptides of mol wt of about 21 kD and 16 kD while the smaller subunits consists of two polypeptides of about 5kD as revealed by SDS-PAGE. The most potent sugar inhibitor of the Lathyrus lectin was found to be α-methyl D-mannoside. The N-terminal amino acid sequence was similar to that of pea lectin sequence.     

The Natural Occurrence of Chickpea Chlorotic Dwarf Geminivirus in Chickpea and Faba Bean in the Sudan

A survey of faba bean and chickpea for virus infection, conducted during February 1994 in the Sudan, showed that bean yellow mosaic potyvirus and broad bean mottle bromovirus occurred commonly in both crops. Chickpea chlorotic dwarf geminivirus (CCDV) was detected for the first time in naturally infected chickpeas and faba beans. This is the first report of natural CCDV infection of chickpeas outside India and the first record of chickpea and faba bean infection in West Asia and North Africa (WANA).     

A mammalian in vitro model to study gangliogenesis from neural crest cells

In spite of considerable advances towards understanding lineages derived from neural crest cells using amphibian and avian embryos, the molecular mechanisms involved in the formation of mammalian peripheral ganglia remain largely unknown, mainly because of the lack of experimental systems that will allow their in vitro manipulation. Here, we present a novel mammalian in vitro model permitting to study gangliogenesis from neural crest cells. This model allowed us to manipulate molecules involved in cell-cell interactions. Our data are in favour of the existence of a hierarchy among adhesion molecules.     

Critical analysis of factors influencing sphaeroplast generation from Saccharomyces cerevisiae

Efficient synthesis of large numbers of viable sphaeroplast from Saccharomyces cerevisiae has been found to be influenced by a number of factors. In this case, Trichoderma harzianum, NCIM 1185, culture filtrate has been used to prepare sphaeroplast from Saccharomyces cerevisiae, NCIM 3288. A method has been devised to isolate large number of viable sphaeroplast from the cell. Detailed analysis of various factors affecting the formation of sphaeroplasts from Saccharomyces cerevisiae has not yet been reported. This study showed critical analysis of various factors which influenced sphaeroplast formation. Most suitable conditions were: Age of the organism in slant — 1 d, cell age in liquid medium — 24 h, time of incubation of cell with 0.3% -mercaptoethanol — 30 min, level of lytic ezyme concentration — 79.2 ml, concentration of cell (dry wt. equivalent) — 0.1262 g, time of contact with lytic enzyme — 25 min, temperature of sphaeroplast formation — 30 °C, phosphate buffer — 25 mM of pH 6.5 and KCl as osmotic stabilizer — 0.7 M.     

Histological and histochemical studies of the male reproductive system of Ligia exotica Roux (Crustacea: Isopoda)

The male reproductive system of Ligia exotica consists of a pair of testes, a pair of vasa deferentia and a pair of genital pores. The testes are tube-like, unpigmented and translucent and each is composed of three elongate, fusiform follicles. The follicular lumen of the mature testis contains spermatogonia, spermatocytes, spermatids and spermatozoa. The histochemical reactions of the testis and the vas deferens show the presence of acidic sulphated mucopolysaccharides and neutral mucopolysaccharides. In addition, they contain basic proteins, tyrosine, disulphide groups, SH-groups, SH-groups, lipids, phospholipids, RNA and DNA.     

A dynamic and intricate regulatory network determines Pseudomonas aeruginosa virulence

Pseudomonas aeruginosa is a metabolically versatile bacterium that is found in a wide range of biotic and abiotic habitats. It is a major human opportunistic pathogen causing numerous acute and chronic infections. The critical traits contributing to the pathogenic potential of P. aeruginosa are the production of a myriad of virulence factors, formation of biofilms and antibiotic resistance. Expression of these traits is under stringent regulation, and it responds to largely unidentified environmental signals. This review is focused on providing a global picture of virulence gene regulation in P. aeruginosa. In addition to key regulatory pathways that control the transition from acute to chronic infection phenotypes, some regulators have been identified that modulate multiple virulence mechanisms. Despite of a propensity for chaotic behaviour, no chaotic motifs were readily observed in the P. aeruginosa virulence regulatory network. Having a ‘birds-eye’ view of the regulatory cascades provides the forum opportunities to pose questions, formulate hypotheses and evaluate theories in elucidating P. aeruginosa pathogenesis. Understanding the mechanisms involved in making P. aeruginosa a successful pathogen is essential in helping devise control strategies.