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751.
Sonia Floris Antonella Fais Rosaria Medda Francesca Pintus Alessandra Piras Amit Kumar Piotr Marek Ku Gunilla Torstensdotter Westermark Benedetta Era 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):517
Washingtonia filifera seeds have revealed to possess antioxidant properties, butyrylcholinesterase and xanthine oxidase inhibition activities. The literature has indicated a relationship between Alzheimer’s disease (AD) and type-2 diabetes (T2D). Keeping this in mind, we have now evaluated the inhibitory properties of W. filifera seed extracts on α-amylase, α-glucosidase enzyme activity and the Islet Amyloid Polypeptide (IAPP) fibrils formation.Three extracts from seeds of W. filifera were evaluated for their enzyme inhibitory effect and IC50 values were calculated for all the extracts. The inhibition mode was investigated by Lineweaver-Burk plot analysis and the inhibition of IAPP aggregate formation was monitored.W. filifera methanol seed extract appears as the most potent inhibitor of α-amylase, α-glucosidase, and for the IAPP fibril formation.Current findings indicate new potential of this extract that could be used for the identification or development of novel potential agents for T2D and AD. 相似文献
752.
Raffaella Mercatelli Tiziana Triulzi Francesco Saverio Pavone Rosaria Orlandi Riccardo Cicchi 《Journal of biophotonics》2020,13(8)
Several specific alterations of the extracellular matrix can be considered a distinctive hallmark of cancer. In particular, a different morphology of the collagen scaffold is frequently found within the peritumoural environment. In this study, we report about a significant difference in the ultrastructural organization of collagen at the supra‐molecular level between the perilesional scaffold and the tumour area in human breast carcinoma samples. In particular, we demonstrated that polarization‐resolved second‐harmonic generation (P‐SHG) microscopy is able to link the altered collagen architecture at the ultrastructural level found in perilesional tissue with a different organization of collagen fibrils at the molecular level. 相似文献
753.
Guido Greco Jr. Donatella Albanesi Maria Cantarella Liliana Gianfreda Rosaria Palescandolo Vincenzo Scardi 《Applied microbiology and biotechnology》1979,8(4):249-261
Summary An ultrafiltration membrane enzymatic reactor is used in connection with different reacting systems.The experimental conditions are such that the enzyme, which operates at fairly high concentration levels because of the concentration polarization phenomena taking place in the reactor, is still in soluble form.The analysis of the system unsteady-state response enables the identification of the mechanism of enzyme deactivation and the extraction of the kinetic parameters of both the deactivation and the main reaction.The stabilizing effect observed in connection with enzyme entrapment within an inert gel deposited onto the U.F. membrane active surface is also discussed.List of Symbols A
U.F. membrane cross sectional area cm2
- CE
Enzyme concentration mg/ml
- CEI
Enzyme concentration at the active membrane surface mg/ml
- CE
Mean enzyme concentration mg/ml
- c
s
o
Substrate concentration in the feed m moles/ml
- c
s
u
Substrate concentration in the outlet m moles/ml
- DE
Enzyme diffusivity cm2/s
- Km
michaelis constant mM
- k2
Kinetic constant of the enzymatic reaction m moles/mg s
- kd
Kinetic constant of the enzyme deactivation reaction s–1
- No
Initial amount of active enzyme mg
- N(t)
Active enzyme amount at reaction time t mg
- Q
Flow rate ml/s
- r
Rate of the main reaction m moles/ml s
- t
Reaction time s
- t*
Reaction time at which product concentration in the outlet is within ± 2% of the steady-state value s
- v
Fluid velocity cm/s
- V
Cell volume ml
- VB
Volume within which 99% of the enzyme fed is contained at the steady-state ml
- VS
Volume within which 99% of the total substrate concentration drop occurs at the steady-state ml
- x
Distance upstream the membrane measured from the membrane surface cm 相似文献
754.
Detection of the mtDNA 14484 mutation on an African-specific haplotype: implications about its role in causing Leber hereditary optic neuropathy. 总被引:3,自引:3,他引:0
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