comparative biochemical study on two marine endophytes, Bacterium SRCnm and Bacillus sp. JS, Isolated from red sea algae

Two marine endophytic bacteria were isolated from the Red Sea algae; a red alga; Acanthophora dendroides and the brown alga Sargassum sabrepandum. The isolates were identified based on their 16SrRNA sequences as Bacterium SRCnm and Bacillus sp. JS. The objective of this study was to investigate the potential anti-microbial and antioxidant activities of the extracts of the isolated bacteria grown in different nutrient conditions. Compared to amoxicillin [25micro g/disk] and erythromycin [15micro g/disk], the extracts of Bacterium SRCnm in media II, III, IV and V were potent inhibitors of the gram-positive bacterium Sarcina maxima even at low concentrations. Also, the multidrug resistant Staphylococcus aureus [MRSA] was more sensitive to the metabolites produced in medium [II] of the same endophyte than erythromycin [15micro g/disk]. A moderate activity of the Bacillus sp. JS extracts of media I and II was obtained against the same pathogen. The total compounds [500ug/ml] of both isolated endophytes showed moderate antioxidant activities [48.9% and 46.1%, respectively]. LC/MS analysis of the bacterial extracts was carried out to investigate the likely natural products produced. Cyclo[D-cis-Hyp-L-Leu], dihydrosphingosine and 2-Amino-1,3- hexadecanediol were identified in the fermentation medium of Bacterium SRCnm, whereas cyclo [D-Pro-L-Tyr] and cyclo [L-Leu-L-Pro] were the suggested compounds of Bacillus sp. JS

Early predictors of increased bone resorption in juvenile idiopathic arthritis: OPG/RANKL ratio, as a key regulator of bone metabolism

To explore early changes in the predictors of bone turnover in children with juvenile idiopathic arthritis [JIA]. To identify osteoprotegerin/receptor activator of nuclear factor-kappaB ligand [OPG/RANKL] ratio in the serum of the same patients and its relation to the parameters of joint inflammation and joint destruction. Seventy children with JIA and 30 healthy children individually matched for age, sex, race, and county of residence were included in this study. Serum levels of calcium [Ca], phosphorus [Ph], alkaline phosphatase [ALP], osteocalcin [OC], RANKL and [OPG] were measured. Urinary concentration of deoxypyridinoline [DPD] was also done. All involved joints were assessed by plain radiography. Significant low serum concentrations of ALP and OPG was observed in JIA group, while there was a significant increase in serum level of RANKL and urine level of DPD compared to controls. OPG/RANKL ratio was significantly lower in JIA patients than in controls. OPG/RANKL ratio is correlated with most clinical characteristics, disease activity variables, JIA outcome measures and radiographic findings. DPD, RANKL and OPG/RANKL ratio, respectively, are considered as independent predictors of juxta-articular osteoporosis. OPG/RANKL ratio was the only predictor of bone erosion. The OPG/RANKL ratio could be an early predictor of increased bone resorption and a valuable biomarker for joint inflammation and bone injury in JIA patients