BACKGROUND: As a convenient and useful physical activity measurement tool,pedometer is widely used in research and intervention about physical activity of population. OBJECTIVE: To assess validity and reliability of the pedometer in measuring daily physical activity. DESIGN,TIME AND SETTING: The experiment was performed at the Department of Kinesiology,Nanjing Institute of Physical Education and Sports from April to June 2007. PARTICIPANTS: Thirty college students,15 majoring in Kinesiology and 15 majoring in social and physical education,15 females and 15 males,with an average age of (20?1) years,were selected from Nanjing Institute of Physical Education and Sports. METHODS: Participants wore a Digi-Walker200 for one week to record results of pedometer measurement,and filled in Bouchard Physical Activity Diary every day to note activity in 24 hours and calculate energy consumption. All participants completed International Physical Activity Questionnaire including large and moderate intensity activity,walking and sitting in a week. MAIN OUTCOME MEASURES: Daily steps,energy expenditure,sedentary time,waking time,exercise time,and weekly physical activity condition. RESULTS: Step counts were positively correlated with daily energy expenditure,walking time,and exercise time,and negatively related with sedentary time. Step counts of different physical activity levels were significantly different: more step counts could better reflect physical activity levels. Furthermore,exercise or continuous walking (more than 15 minutes) could significantly increase step counts. Daily physical activity including 30-minute moderate intensity activity could achieve or exceed the target steps of 10 000. CONCLUSION: Pedometer provides a useful and objective indicator of daily step counts assessing daily physical activity,but it is difficult to reflect activity intensity and patterns.

To demonstrate the fructose metabolism pathway in Bifidobacterium Longum NCC2705 and to construct its fermentation model, we explored the comparative proteome cultivating the strain on glucose or fructose, based on a proteomic reference map of B. longum NCC2705 constructed earlier. Then, we used matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry and electro-spray ionization tandem mass spectrometry (ESI-MS/MS) for differently expressed proteins identification. Furthermore, with semi-quantitative RT-PCR we determined the distinctively expressed proteins at the level of transcription. Proteomic comparison of glucose- and fructose-grown cells demonstrated much similarity. On the page of fructose there were all the enzymes and proteins that exist during the process of glucose degradation. We observed a greater variation of more than three-fold for the identified 9 spots representing 5 protein entries by MALDI-TOF MS. The sugar-binding protein specific to fructose (BL0033) and an ABC transporter ATP binding protein (BL0034) showed higher expression level from cells grown on fructose. It was also determined by semi-quantitative RT-PCR subsequently. BL0033 time course and concentration experiments showed that the induction time correlated to higher fructose concentration, and increased expression of BL0033. Fructose was catabolized via the same degradation pathway as glucose at the level of proteomics. BL0033 was induced by fructose. All results suggest that the uptake of fructose into the cell may be conducted by a specific ABC transport system, in which BL0033 and BL0034 as components might have played an important role.
Bifidobacterium ; chemistry ; genetics ; metabolism ; Culture Media ; Fermentation ; Fructose ; pharmacology ; Glucose ; pharmacology ; Proteome ; analysis ; genetics ; Proteomics ; methods

Three hundred and twenty endophytic actinobacterial strains were isolated from psammophytes collected from Taklamakan Desert and identified.Among them,three strains already had been identified as new species of two genera and sixteen isolates showed relatively low 16S rRNA similarities＜98.6％to validly described species.Seventy-five of the isolates were selected as representative strains to screen antibacterial activity and mechanism.Forty-seven strains showed antagonistic activity against at least one of the indicator bacteria.Two Streptomyces strains produced bioactive compounds inducing DNA damage,and two Streptomyces strains produced bioactive compounds with inhibitory activity on protein biosynthesis.Notably,the strain Streptomyces sp.8P21H-1 that demonstrated both strong antibacterial activity and inhibitory activity on protein biosynthesis was prioritized for exploring new antibiotics.Under the strategy of integrating genetics-based discovery program and MS/MS-based molecular networking,two new streptogramin-type antibiotics,i.e.,acetyl-griseoviridin and desulphurizing gri-seoviridin,along with known griseoviridin,were isolated from the culture broth of strain 8P21H-1.Their chemical structures were determined by HR-MS,and 1D and 2D NMR.Desulphurizing griseoviridin and griseoviridin exhibited antibacterial activities by inhibiting translation.