No abstract

Sarcina marina (NCMB 778) grew over the temperature range 20-45 degrees C but no growth was recorded at 15 degrees C or 50 degrees C. At the optimum growth temperature of 34 degrees C the doubling time was 14.5 h. The major polar lipid components, tentatively identified as the diether analogues of phosphatidyl glycerophosphate (PGP), phosphatidyl glycerol (PG), diglycosyl diglyceride (DGD) and triglycosyl diglyceride (TGD), and the major neutral lipid components, tentatively identified as squalene, dihydrosqualene, tetrahydrosqualene, vitamin MK8, geranyl geraniol and di-O-phytanyl glycerol, are identical to those found in other extremely halophilic rods and cocci. The total lipid content varied with growth conditions from 0.6-3.2% of the dry cell weight, polar lipids accounted for between 94.3 and 83.6% of the total lipid, the remainder being neutral lipid. In response to both the transition from exponential to stationary phase and a reduction of 14 degrees C in growth temperature, batch cultures showed: (i) an increase in total lipid content; (ii) a decrease in PG and (iii) an increase in PGP. Specific responses to the temperature decrease were (i) increased total lipid content; (ii) no decrease in neutral lipids in stationary phase; (iii) marked reduction in PG and (iv) raised DGD. (i) and (ii) could be mechanisms for increasing membrane fluidity. In common with all other extreme halophiles investigated the alkyl side chains of S. marina polar lipids were identified as the phytanyl (3R, 7R, 11R, 15-tetramethylhexadecyl) group. Its structure did not appear to vary with temperature so that the normal mechanisms for modifying the structure of lipid alkyl side chains to modulate membrane fluidity in response to temperature changes probably does not occur in this group of microorganisms.

The relationships between the percent body fat and other nutritional predictors were assessed among forty male and forty female children aged 2 -10 years. Both sexes were age -matched. There was no significant difference in age between the two groups (P >0.001

This study aimed to investigate the short-term effects of Highly Active Antiretroviral Therapy (HAART) (stavudine, lamivudine and nevirapine) on serum lipids of HIV-1 positive subjects in Benin City, Nigeria. Test group 1 (n=78) and test group 2 (n= 71) comprised HIV-1 seropositive individuals on HAART for a period of one to three months; and five to six months respectively. Fifty five newly diagnosed HIV-1 positive subjects naïve to HAART served as control group 1 and sixty apparently healthy HIV-1 seronegative individuals served as control group 2. The blood samples obtained were analyzed for total cholesterol, triglycerides, low-density lipoprotein and high-density lipoprotein using standard enzymatic methods. Total cholesterol of test group 2 (214.0±6.43mg/dL) was not significantly different from Test group 1 (202.4±5.09mg/dL), both were however significantly higher than control group 1 (159.3±5.09mg/dL) and control group 2 (101.6±3.76 mg/dL). Triglyceride concentration of test group 2 (106.6+11.95mg/dL) was not significantly different from test group 1 (135.8+9.88mg/dL), but were significantly different from control groups 1 and 2 (125.1+3.35mg/dL and 104.6+3.08mg/dL) respectively. Dyslipidemia could set in from 1 to 6 months of HAART usage in HIV-1 Positive subjects hence serum lipids should be monitored as early as one month of HAART commencement.