Effects of NaCl and iso-osmotic PEG stress on growth,osmolytes accumulation and antioxidant defense in cultured sugarcane cells

In order to discriminate between the ionic and osmotic components of salt stress, sugarcane (Saccharum officinarum L. cv. Co 86032) calli were cultured on media containing NaCl or polyethylene glycol (PEG) 8000 that exerted the same osmotic pressure (−0.7 MPa). PEG stress exposure for 15 days led to significant growth reduction and loss in water content than salt stressed and control tissues. Osmotic adjustment (OA) was observed in callus tissues grown on salt, but was not evident in callus grown on PEG. Oxidative damage to membranes, estimated in terms of accumulation of thiobarbituric acid reactive substances-TBARS and electrolytic leakage was significantly higher in both the stressed calli than the control however, the extent of damage was more in the PEG stressed calli. The stressed callus tissues showed inhibition of ascorbate peroxidase activity, while catalase activity was increased. These results indicate sensitivity of cells to PEG-mediated stress than salt stress and differences in their OA to these two stress conditions. The sensitivity to the osmotic stress indicate that expression of the stress tolerance response requires the coordinated action of different tissues in a plant and hence was not expressed at the cellular level.     

Role of Ca2+ ion on Leishmania-macrophage attachment

Summary Leishmania donovani, the etiological agent for the disease visceral leishmaniasis, attach themselves to the macrophages for initiation of the disease. The attachment process has been found to be regulated by Ca²⁺ ions. Verapamil, a Ca²⁺-channel blocker inhibits Leishmania-macrophage attachment. The inhibitory effect is increased with time. Nifedipine, another Ca²⁺-channel blocker exhibits the same effect. The attachment process is stimulated by Ca²⁺-ionophore alone. The inhibitory effects of the calcium channel blockers are reversed by the ionophore.     

Effect of type of intravaginal progestagen treatment of estrous response and reproductive performance of ewes

A comparison was made of the relative effectiveness of sponge pessaries impregnated with 40mg flourogestone acetate (FGA) or 60mg medroxyprogesterone acetate (MAP) to induce a synchronized estrus in ewes. Ewes were treated with sponge pessaries for 14 days and 500 IU pregnant mares' serum gonadotropin was injected i.m. at the time of sponge removal. The degree and pattern of mating response of ewes were similar, irrespective of the treatment used, approximately 92% of the ewes being marked by the ram by 72h after sponge removal. No significant differences in fertility or litter size were observed between the treatment groups. Ewes treated with FGA sponges had a fertility of 53% and litter size of 2.3 after mating at the synchronized estrus. The corresponding values for ewes treated with MAP sponges were 57% and 2.1. Use of MAP sponges was associated with a 17.8% sponge loss during treatment compared with 1% sponge loss in ewes treated with FGA sponges. Such losses could compromise the use of MAP sponges by reducing their overall efficacy.     

Lithium in drinking water and the incidences of crimes,suicides, and arrests related to drug addictions

Using data for 27 Texas counties from 1978-1987, it is shown that the incidence rates of suicide, homicide, and rape are significantly higher in counties whose drinking water supplies contain little or no lithium than in counties with water lithium levels ranging from 70-170 micrograms/L; the differences remain statistically significant (p less than 0.01) after corrections for population density. The corresponding associations with the incidence rates of robbery, burglary, and theft were statistically significant with p less than 0.05. These results suggest that lithium has moderating effects on suicidal and violent criminal behavior at levels that may be encountered in municipal water supplies. Comparisons of drinking water lithium levels, in the respective Texas counties, with the incidences of arrests for possession of opium, cocaine, and their derivatives (morphine, heroin, and codeine) from 1981-1986 also produced statistically significant inverse associations, whereas no significant or consistent associations were observed with the reported arrest rates for possession of marijuana, driving under the influence of alcohol, and drunkenness. These results suggest that lithium at low dosage levels has a generally beneficial effect on human behavior, which may be associated with the functions of lithium as a nutritionally-essential trace element. Subject to confirmation by controlled experiments with high-risk populations, increasing the human lithium intakes by supplementation, or the lithiation of drinking water is suggested as a possible means of crime, suicide, and drug-dependency reduction at the individual and community level.     

Sublocalization of an Ataxia-Telangiectasia Gene Distal to D11S384 by Ancestral Haplotyping In Costa Rican Families

In an effort to localize a gene for ataxia-telangiectasia (A-T), we have genotyped 27 affected Costa Rican families, with 13 markers, in the chromosome 11q22-23 region. Significant linkage disequilibrium was detected for 9/13 markers between D11S1816 and D11S1391. Recombination events observed in these pedigrees places A-T between D11S1819 and D11S1960. One ancestral haplotype is common to 24/54 affected chromosomes and roughly two-thirds of the families. Inferred (ancestral) recombination events involving this common haplotype in earlier generations suggest that A-T is distal to D11S384 and proximal to D11S1960. Several other common haplotypes were identified, consistent with multiple mutations in a single gene. When considered together with all other evidence, this study further sublocalizes the major A-T locus to ≈200 kb, between markers S384 and S535.     

Recovery of Lyme disease spirochetes from patients.

Since the summer of 1982, we have cultured patient specimens for Lyme disease spirochetes. Of 118 patients cultured, four specimens yielded spirochetes: two from blood, one from a skin biopsy specimen of erythema chronicum migrans (ECM), and one from cerebrospinal fluid. All four isolates appeared identical when examined with a monoclonal antibody. However, attempts to recover the spirochete from synovium or synovial fluid were unsuccessful. In addition, the organism could not be visualized in skin or synovial biopsy specimens using the avidin-biotin peroxidase complex detection system. Thus, the current yield in culturing spirochetes from patients is quite low, and it is not yet known whether the organism is still alive later in the disease when arthritis is present.