ABSTRACT
CONTEXT: Timed up-and-go (TUG) test is a valid, reliable, and an objective test for quantifying functional mobility and assessing the fall risk in all age groups. The analysis of patient scores on TUG test is limited by lack of data, having a wide range of performance scores among people without disabilities. AIM: The objective of the study was to provide the reference value for TUG test in healthy individuals of Gujarat, India. SUBJECTS AND METHODS: It was a cross-sectional observational study. Five hundred and twenty healthy individuals, aged 40-70 years, were recruited from various regions of Gujarat based on convenient sampling. All the participants were made to perform TUG test in a controlled environment in community. Three readings of the actual test were obtained and averaged. RESULTS: Data were analyzed with mean, standard deviation, confidence intervals (CIs 95%) and Pearson's correlation coefficient (r) with α = 0.05 by age groups (40-50, 51-60, and 61-70 years) and gender. The mean (CI 95%) TUG time for healthy adults of Gujarat was 8.46 (8.35-8.57) s and demonstrated age-related decline for both male and female participants. TUG time also demonstrated strong correlation with the height of individuals. CONCLUSION: This preliminary data can be used as a reference only for specific population with specific age groups due to variability in test results among the different population due to age, gender, anthropometric measures such as height, weight, and body mass index, geographical variation, nutritional support, and cognitive status.
ABSTRACT
The photoactive yellow protein (PYP) from Halorhodospira halophila (Hhal) is a bacterial photoreceptor and model system for exploring functional protein dynamics. We report ultrafast spectroscopy experiments that probe photocycle initiation dynamics in the PYP domain from the multidomain PYP-phytochrome-related photoreceptor from Rhodospirillum centenum (Rcen). As with Hhal PYP, Rcen PYP exhibits similar excited-state dynamics; in contrast, Rcen PYP exhibits altered photoproduct ground-state dynamics in which the primary I0 intermediate as observed in Hhal PYP is absent. This property is attributed to a tighter, more sterically constrained binding pocket around the p-coumaric acid chromophore due to a change in the Rcen PYP protein structure that places Phe98 instead of Met100 in contact with the chromophore. Hence, the I0 state is not a necessary step for the initiation of productive PYP photocycles and the ubiquitously studied Hhal PYP may not be representative of the broader PYP family of photodynamics.
Subject(s)
Bacterial Proteins/chemistry , Halorhodospira halophila , Photoreceptors, Microbial/chemistry , Spectrum Analysis , Coumaric Acids , Phytochrome/metabolism , PropionatesABSTRACT
An important bottleneck in the use of infrared spectroscopy as a powerful tool for obtaining detailed information on protein structure is the assignment of vibrational modes to specific amino acid residues. Side-chain specific isotopic labeling is a general approach towards obtaining such assignments. We report a method for high yield isotope editing of the bacterial blue light sensor photoactive yellow protein (PYP) containing ring-D(4)-Tyr. PYP was heterologously overproduced in Escherichia coli in minimal media containing ring-D(4)-Tyr in the presence of glyphosate, which inhibits endogenous biosynthesis of aromatic amino acids (Phe, Trp, and Tyr). Mass spectrometry of the intact protein and of tryptic peptides unambiguously demonstrated highly specific labeling of all five Tyr residues in PYP with 98% incorporation and undetectable isotopic scrambling. FTIR spectroscopy of the protein reveals a characteristic Tyr ring vibrational mode at 1515 cm(-1) that is shifted to 1436 cm(-1), consistent with that from ab initio calculations. PYP is a model system for protein structural dynamics and for receptor activation in biological signaling. The results described here open the way to the analysis of PYP using isotope-edited FTIR spectroscopy with side-chain specific labeling.
