Efficacy of foliar extracts against pre- and post-harvest diseases of sponge-gourd fruits

S.K. AHMAD AND J.S. PRASAD. 1995. The inhibitory potential of aqueous foliar extracts of Adhatoda vasica, Azadirachta indica, Catharanthes roseus, Datura fistulosa, Lantana camara, Muraya exotica, Ocimum sanctum, Ricinus communis and Strychnos nux-vomica were evaluated against soft rot diseases of sponge-gourd fruits caused by Helminthosporium spiciferum and Fusarium scirpi. Conidial germination of F. scirpi and H. spiciferum were reduced to about 75% when their spores were treated with A. indica, C. roseus, D. fistulosa, L. camara, M. exotica and O. sanctum. Considerable reductions (50%) in mycelial dry weights and colony diameters were recorded in liquid media containing (20%) aqueous extracts of C. roseus, D. fistulosa and M. exotica . Other extracts reduced the mycelial growth but to a lesser extent. Post-infection treatment of sponge-gourd fruits with the extracts of A. indica, L. camara, M. exotica, O. sanctum, D. fistulosa and C. roseus almost fully inhibited the spread of disease. Treatment of fruits with A. indica and C. roseus before fungal infection reduced the spread of disease caused by both the pathogens, whereas M. exotica, O. sanctum and D. fistulosa reduced the spread of soft-rot caused by F. scirpi but not by H. spiciferum .     

Free and total thyroid hormones in humans at extreme altitude

Alterations in circulatory levels of total T₄ (TT₄), total T₃ (TT₃), free T₄ (FT₄), free T₃ (FT₃), thyrotropin (TSH) and T₃ uptake (T₃U) were studied in male and female sea-level residents (SLR) at sea level, in Armed forces personnel staying at high altitude (3750 m) for prolonged duration (acclimatized lowlanders, ALL) and in high-altitude natives (HAN). Identical studies were also performed on male ALL who trekked to an extreme altitude of 5080 m and stayed at an altitude of more than 6300 m for about 6 months. The total as well as free thyroid hormones were found to be significantly higher in ALL and HAN as compared to SLR values. Both male as well as female HAN had higher levels of thyroid hormones. The rise in hormone levels in different ALL ethnic groups drawn from amongst the southern and northern parts of the country was more or less identical. In both HAN and ALL a decline in FT₃ and FT₄ occurred when these subjects trekked at subzero temperatures to extreme altitude of 5080 m but the levels were found to be higher in ALL who stayed at 6300 m for a prolonged duration. Plasma TSH did not show any appreciable change at lower altitudes but was found to be decreased at extreme altitude. The increase in thyroid hormones at high altitude was not due to an increase in hormone binding proteins, since T₃U was found to be higher at high altitudes. A decline in TSH and hormone binding proteins and an increase in the free moiety of the hormones is indicative of a subtle degree of tissue hyperthyroidism which may be playing an important role in combating the extreme cold and hypoxic environment of high altitudes.     

The effect of viral regulatory protein expression on gene delivery by human immunodeficiency virus type 1 vectors produced in stable packaging cell lines.

We describe the generation of stable human immunodeficiency virus type 1 (HIV-1)-packaging lines that constitutively express high levels of HIV-1 structural proteins in either a Rev-dependent or a Rev-independent fashion. These cell lines were used to assess gene transfer by using an HIV-1 vector expressing the hygromycin B resistance gene and to study the effects of Rev, Tat, and Nef on the vector titer. The Rev-independent cell lines were created by using gag-pol and env expression vectors that contain the Mason-Pfizer monkey virus (MPMV) constitutive transport element (CTE). Vector titers approaching 10(4) CFU/ml were routinely obtained with these cell lines, as well as with the Rev-dependent cell lines, with HeLa-CD4 cells as targets. The presence of Nef and Tat in the producer cell each increased the vector titer 5- to 10-fold. Rev, on the other hand, was absolutely essential for gene transfer, unless the MPMV CTE was present in the vector. In that case, by using the Rev-independent cell lines for packaging, Rev could be completely eliminated from the system without a reduction in vector titer.     

Post-coital agents and menses inducing drugs

The importance of developing of drugs which could be taken post-coitally or used once-a-month in the case of a delay in the onset of the menses is well recognized. The availability of such technology would limit exposure to fertility regulating agents to such occasions where there is coital exposure or possibility of pregnancy.Methods of post-coital contraception used so far include IUD’s inserted post-coitally, estrogens, and combinations of estrogens and gestagens. These are reserved primarily for emergency situations to protect women from unwanted pregnancy resulting from rape or unprotected coitus. Levonorgestrel has shown satisfactory results in terms of contraceptive efficacy and is being further evaluated clinically. A number of problems inherent in the development of post-coital contraception are discussed.Menstrual regulation could be achieved by a number of approaches: (a) block progesterone receptors and interfere with the preparation of the endometrium for implantation; (b) luteolysis leading to decreased progesterone levels and interruption of implantation; and (c) termination of early pregnancy by prostaglandins. A number of progesterone antagonists have been evaluated. One of the compounds, RU38486 is being evaluated clinically for termination of very early pregnancy.Deglycosylated derivatives of human chorionic gonadotropin have been shown to antagonize the action of human chorionic gonadotropin and interfere with established pregnancy in rats. Appropriate methods of delivery, immunogenicity and alternate methods for production of human chorionic gonadotropin need to be considered before evaluation of the derivatives for clinical use. In vitro and invivo models need to be developed for evaluation of the teratogenicity and embryotoxicity of post-coital and menses inducing agents.There are a number of gaps in the knowledge of the processes regulating implantation which should be investigated in rodents and in different non-human primate species.     

Organization and dynamics of lipids in bovine brain coated and uncoated vesicles

Three characteristics have been demonstrated by the chemical analysis of bovine brain coated vesicles following removal of the coat proteins: a high protein content, a high cholesterol/lipid ratio and a high percentage of phosphatidylethanolamine amongst the phospholipids.The study of lipid bilayer organization and dynamics has been performed using the fluorescent probes pyrene and parinaric acid (cis and trans). This has allowed the study of both lateral mobility and rotational motion in the lipid bilayer of the coated and uncoated vesicles.Lateral mobility in the fluid phase of the lipid is slightly reduced by the presence of the clathrin coat, as indicated by the lower diffusion coefficient of pyrene in coated compared with uncoated vesicles.At all temperatures from 6° to 30°C, solid-phase domains, probed by trans parinaric acid, coexist with fluid-phase domains in the lipid bilayer. The temperature dependence of the parinaric acid lifetimes and of their amplitudes strongly suggests that the solid phase domains decrease in size with temperature, both in coated and uncoated vesicles.However, the difference in the value of the anisotropy at long times (r ), between coated and uncoated vesicles (a difference which is more pronounced for cis than for trans parinaric acid), indicates that the presence of the clathrin coat introduces disorder in the surrounding lipids, thus suggesting a possible role of the clathrin in the formation of the pits on the plasma membrane.Abbreviations CVs coated vesicles - UVs uncoated vesicles - TLC thin layer chromatography - DMSO dimethylsulfoxide - DPPC dipalmitoylphosphatidylcholine - cis Pna cis parinaric acid - (9,11,13,15-cis-trans-trans-cis) octadecatetraenoic acid - Trans Pna Trans parinaric acid - (9,11,13,15-all-trans) octadecatetraenoic acid     

Response of the epididymis, ductus deferens & accessory glands of the castrated prepubertal rhesus monkey to exogenous administration of testosterone or 5alpha-dihydrotestosterone.

The response of the epididymis, ductus deferens, and accessory glands of the castrated prepubertal rhesus monkey to exogenous administration of testosterone or 5alpha-dihydrotestosterone (DHT) was investigated. 200 or 800 mcg of either steroid/day were administered for 60 days beginning on the day after castration. Castration caused a marked regression of the weight of and secretory function of the reproductive organs; testosterone/DHT stimulated their growth and secretory activity which were maintained at the level of the controls. The weight of the caput epididymides however, was unaffected by testosterone but was stimulated by DHT. DHT caused a greater stimulation of the growth and secretory activity of the reproductive organs than testosterone and also caused a hyperstimulation of secretion by the seminal vesicles. The data, analyzed statistically, show that the accessory organs of the prepubertal rhesus monkey are affected by castration and vary in their response to stimulation by exogenous androgens.     

Regional differences in the metabolism of testosterone in vitro in the epididymis & ductus deferens of the adult rhesus monkey Macaca mulatta.

Regional differences in the metabolism of testosterone in vitro in the epididymis (1.5 cm segments) and ductus deferens (2 cm segments) were investigated in the adult rhesus monkey, Macaca mulatta. The conversion of tritiated testosterone to its 5alpha-reduced derivatives increased from the proximal to the distal regions of the epididymis. The total amount of 5alpha-reduced products in the subsequent segments of the epididymis was highest in the intact monkey and on the intact side of the unilaterally castrated monkey and was followed in decreasing order by the castrated side of the hemiscastrate and least in the bilateral castrate. Hormonal requirements for maintenance of the biological functions of the epididymis and maturation of spermatozoa in the epididymis are discussed.     

Effects of a highly purified antiserum to FSH on testicular function in immature rats

Effects of highly purified antiserum (AS) to follicle stimulating hormone (FSH) on testicular function was studied in immature rats. Treatment with FSHAS for 10 days, from 25-34, decreased weights of the testis (p .001) and increased weights of the epididymis (p .05). Numbers of the cell types in the seminiferous epithelium, particularly Type A spermatogonia pachytene spermatocytes and spermatids, were markedly reduced, possibly due to: 1) decreased division of the initial stem cells, 2) impairment of division of Type B spermatogonia and their transformation to pachytene spermatocytes, and 3) desquamation and degeneration of pachytene spermatocytes and spermatids. FSHAS also affected the sertoli cell function which was reflected in the decreased binding of androgens to supernatant fraction of the testis and epididymides. Treatment with luteinizing hormone-AS for 5 days did not affect testicular function but the binding of androgens to the supernatants of the caput and cauda epididymides and ventral prostate was significantly reduced (p .001). These data indicate that FSH is necessary for the maintenance of the cellular integrity of the seminiferous epithelium during the completion of the 1st wave of spermatogenesis.