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61.
62.
Twenty four shift workers (8 from a steel industry and 16 from a Government hospital) participated in the study. The subjects
were instructed to self-measure oral temperature, 4 6 times a day for about three weeks. Sleep quantity and quality for each
subject were analysed with the help of an appropriate inventory. The data were analysed by cosinor and power spectrum methods.
The frequency of circadian rhythm detection was in the order of 48% in senior nurses, 29% in steel plant workers and 14% in
junior nurses. These were also complemented by the results of power spectrum analysis. Present results suggest that rhythms
of subjective fatigue and subjective drowsiness are governed neither by oral temperature oscillator nor by the sleep/wake
cycle oscillator. The results show that shift rotation pattern chiefly modulates the circadian time structure of shift workers.
It is also suggested that the phenomenon of circadian rhythm desynchronization in oral temperature appears to be independent
of per day total sleep length. 相似文献
63.
Regulation of invertase levels in Avena stem segments by gibberellic Acid, sucrose, glucose, and fructose 总被引:8,自引:5,他引:3
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Gibberellic acid and sucrose play significant roles in the increases in invertase and growth in Avena stem segments. About 80% of invertase is readily solubilized, whereas the rest is in the cell wall fraction. The levels of both types of invertase change in a similar manner in the response to gibberellic acid and sucrose treatment. The work described here was carried out with only the soluble enzyme. In response to a treatment, the level of invertase activity typically follows a pattern of increase followed by decrease; the increase in activity is approximately correlated with the active growth phase, whereas the decrease in activity is initiated when growth of the segments slows. A continuous supply of gibberellic acid retards the decline of enzyme activity. When gibberellic acid was pulsed to the segments treated with or without sucrose, the level of invertase activity increased at least twice as high in the presence of sucrose as in its absence, but the lag period is longer with sucrose present. Cycloheximide treatments effectively abolish the gibberellic acid-promoted growth, and the level of enzyme activity drops rapidly. Decay of invertase activity in response to cycloheximide treatment occurs regardless of gibberellic acid or sucrose treatment or both, and it is generally faster when the inhibitor is administered at the peak of enzyme induction than when given at its rising phase. Pulses with sucrose, glucose, fructose, or glucose + fructose elevate the level of invertase significantly with a lag of about 5 to 10 hours. The increase in invertase activity elicited by a sucrose pulse is about one-third that caused by a gibberellic acid pulse given at a comparable time during mid-phase of enzyme induction, and the lag before the enzyme activity increases is nearly twice as long for sucrose as for gibberellic acid. Moreover, the gibberellic acid pulse results in about three times more growth than the sucrose pulse. Our studies support the view that gibberellic acid, as well as substrate (sucrose) and end products (glucose and fructose), play a significant role in regulating invertase levels in Avena stem tissue, and that such regulation provides a mechanism for increasing the level of soluble saccharides needed for gibberellic acid-promoted growth. 相似文献
64.
65.
Katherine M. Partridge Stephen Antonysamy Shobha N. Bhattachar Srinivasan Chandrasekhar Matthew J. Fisher Adrian Fretland Karen Gooding Anita Harvey Norman E. Hughes Steven L. Kuklish John G. Luz Peter R. Manninen James E. McGee Daniel R. Mudra Antonio Navarro Bryan H. Norman Steven J. Quimby Matthew A. Schiffler Xiao-Peng Yu 《Bioorganic & medicinal chemistry letters》2017,27(6):1478-1483
We describe a novel class of acidic mPGES-1 inhibitors with nanomolar enzymatic and human whole blood (HWB) potency. Rational design in conjunction with structure-based design led initially to the identification of anthranilic acid 5, an mPGES-1 inhibitor with micromolar HWB potency. Structural modifications of 5 improved HWB potency by over 1000×, reduced CYP2C9 single point inhibition, and improved rat clearance, which led to the selection of [(cyclopentyl)ethyl]benzoic acid compound 16 for clinical studies. Compound 16 showed an IC80 of 24 nM for inhibition of PGE2 formation in vitro in LPS-stimulated HWB. A single oral dose resulted in plasma concentrations of 16 that exceeded its HWB IC80 in both rat (5 mg/kg) and dog (3 mg/kg) for over twelve hours. 相似文献
66.
Screening,statistical optimized production,and application of β‐mannanase from some newly isolated fungi
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Hemant Soni Hemant Kumar Rawat Saroj Ahirwar Naveen Kango 《Engineering in Life Science》2017,17(4):392-401
Eighty‐eight fungi isolated from soil and decaying organic matter were screened for mannanolytic activity. Twenty‐eight fungi produced extracellular mannanase on locust bean gum as evidenced by zone of hydrolysis produced on mannan agar gel. Six prominent producers, including four Fusarium species namely Fusarium fusarioides NFCCI 3282, Fusarium solani NFCCI 3283, Fusarium equiseti NFCCI 3284, Fusarium moniliforme NFCCI 3287 with Cladosporium cladosporioides NFCCI 3285 and Acrophialophora levis NFCCI 3286 produced the β‐mannanase in the range of 84–140 nkat/mL. All these grew well on particulate substrates in solid‐state fermentation (SSF), producing relatively higher titers on mannan‐rich palm kernel cake (PKC) and copra meal. Two high yielding strains, F. equiseti (1747 nkat/gds) and A. levis (897 nkat/gds) were selected for statistical optimization of mannanase on PKC. Interaction of two critical solid state fermentation parameters, pH and moisture on mannanase production by these two molds was studied by response surface method. Optimized production on PKC resulted in three‐ to fourfold enhancement in enzyme yield was observed in case of F. equiseti (5945 nkat/gds) and A. levis (4726 nkat/gds). HPLC analysis of mannan hydrolysate indicated that F. equiseti and A. levis mannanase performed efficient hydrolysis of konjac gum (up to 99%) with exclusive mannooligosaccahride (DP of 4) production. A seminative SDS‐PAGE revealed that A. levis and F. solani produced three isoforms, F. moniliforme produced two isoforms while F. fusarioides, F. equiseti, and C. cladosporioides produced a single enzyme. 相似文献
67.
The effect of pH, aeration and mixing on the growth and production of carbonyl reductase by Candida viswanathii was investigated in a 6.6-l fermentor. Controlling the pH at 8.0 had a very significant effect on the enzyme production.
Aeration and agitation influenced the dissolved oxygen concentration which in turn affected growth as well as enzyme production.
A maximum carbonyl reductase activity (53 Umg−1) was attained in 24 h under the optimal cultivation conditions of controlled pH at 8.0, aeration rate 1 vvm and an agitation
speed of 250 rpm at 25°C. The enzyme activity was twice as high (56 Umg−1) in the fermentor as compared to a shake flask. Further, the duration of growth and enzyme production in the fermentor was
shortened. Cells cultivated under the optimized conditions were used for the preparative scale reduction of N, N-dimethyl-(3-keto)-2-thienyl-propanamine
to (S)-N, N-dimethyl-(3-hydroxy)-2-thienyl-propanamine, a key intermediate in the production of the important antidepressant drug
(S)-duloxetine. 相似文献
68.
Kumar Srivastava B Soni R Patel JZ Jha S Shedage SA Gandhi N Sairam KV Pawar V Sadhwani N Mitra P Jain MR Patel PR 《Bioorganic & medicinal chemistry letters》2008,18(14):3882-3886
Facile synthesis of biaryl pyrazole sulfonamide derivative of 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxylic acid piperidin-1-ylamide (SR141716, 1) and an investigation of the effect of replacement of the –CO group in the compound 1 by the –SO2 group in the aminopiperidine region is reported. Primary ex-vivo pharmacological testing and in vitro screening of sulfonamide derivative 2 showed the loss of CB1 receptor antagonism. 相似文献
69.
Srivastava BK Soni R Joharapurkar A Sairam KV Patel JZ Goswami A Shedage SA Kar SS Salunke RP Gugale SB Dhawas A Kadam P Mishra B Sadhwani N Unadkat VB Mitra P Jain MR Patel PR 《Bioorganic & medicinal chemistry letters》2008,18(3):963-968
Design, synthesis and conformational analysis of few imidazole and oxazole as bioisosters of 4S-(-)-3-(4-chlorophenyl)-N-methyl-N'-[(4-chlorophenyl)-sulfonyl]-4-phenyl-4,5-dihydro-1H-pyrazole-1-caboxamidine (SLV-319) 2 is reported. Computer assisted conformational analysis gave a direct clue for the loss of CB1 antagonistic activity of the ligands without a fine docking simulation for the homology model. 相似文献
70.
Manfred T. Reetz Pankaj Soni Layla Fernández 《Biotechnology and bioengineering》2009,102(6):1712-1717
In rare but nevertheless important cases it is of practical interest to decrease the thermostability of an enzyme, that is, to increase thermolability in a controlled manner. In the present model study, this unconventional goal has been reached by applying directed evolution to the lipase from Pseudomonas aeruginosa (PAL). By utilizing the B‐factor iterative test (B‐FIT), previously developed to increase the thermostability of enzymes, it was possible to reduce the value from 71.6°C in the case of wild type (WT‐PAL) to 35.6°C (best mutant) without affecting the catalytic profile in terms of substrate acceptance or enantioselectivity at room temperature. Accordingly, saturation mutagenesis was performed at sites in PAL, which on the basis of its X‐ray structure, have the lowest B‐factors indicative of high rigidity. Focused mutations were introduced which can be expected to decrease rigidity, the ensuing increased flexibility leading to higher thermolability without changing the actual catalytic profile. Biotechnol. Bioeng. 2009;102: 1712–1717. © 2008 Wiley Periodicals, Inc. 相似文献