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排序方式: 共有726条查询结果,搜索用时 46 毫秒
721.
Emanuela Bastonini Daniela Kovacs Salvatore Raffa Marina delle Macchie Alessia Pacifico Paolo Iacovelli Maria Rosaria Torrisi Mauro Picardo 《Cell death & disease》2021,12(4)
A growing number of studies supports the existence of a dynamic interplay between energetic metabolism and autophagy, whose induction represents an adaptive response against several stress conditions. Autophagy is an evolutionarily conserved and a highly orchestrated catabolic recycling process that guarantees cellular homeostasis. To date, the exact role of autophagy in vitiligo pathogenesis is still not clear. Here, we provide the first evidence that autophagy occurs in melanocytes and fibroblasts from non-lesional skin of vitiligo patients, as a result of metabolic surveillance response. More precisely, this study is the first to reveal that induction of autophagy exerts a protective role against the intrinsic metabolic stress and attempts to antagonize degenerative processes in normal appearing vitiligo skin, where melanocytes and fibroblasts are already prone to premature senescence.Subject terms: Macroautophagy, Translational research 相似文献
722.
Andrea Bucci Edlira Skrami Andrea Faragalli Rosaria Gesuita Roberto Cameriere Flavia Carle Luigi Ferrante 《Biometrical journal. Biometrische Zeitschrift》2019,61(6):1575-1594
Forensic age estimation is receiving growing attention from researchers in the last few years. Accurate estimates of age are needed both for identifying real age in individuals without any identity document and assessing it for human remains. The methods applied in such context are mostly based on radiological analysis of some anatomical districts and entail the use of a regression model. However, estimating chronological age by regression models leads to overestimated ages in younger subjects and underestimated ages in older ones. We introduced a full Bayesian calibration method combined with a segmented function for age estimation that relied on a Normal distribution as a density model to mitigate this bias. In this way, we were also able to model the decreasing growth rate in juveniles. We compared our new Bayesian‐segmented model with other existing approaches. The proposed method helped producing more robust and precise forecasts of age than compared models while exhibited comparable accuracy in terms of forecasting measures. Our method seemed to overcome the estimation bias also when applied to a real data set of South‐African juvenile subjects. 相似文献
723.
Chiara Tarracchini Chiara Argentini Giulia Alessandri Gabriele Andrea Lugli Leonardo Mancabelli Federico Fontana Rosaria Anzalone Alice Viappiani Francesca Turroni Marco Ventura Christian Milani 《Microbial biotechnology》2023,16(9):1774-1789
The lower female reproductive tract is notoriously dominated by Lactobacillus species, among which Lactobacillus crispatus emerges for its protective and health-promoting activities. Although previous comparative genome analyses highlighted genetic and phenotypic diversity within the L. crispatus species, most studies have focused on the presence/absence of accessory genes. Here, we investigated the variation at the single nucleotide level within protein-encoding genes shared across a human-derived L. crispatus strain selection, which includes 200 currently available human-derived L. crispatus genomes as well as 41 chromosome sequences of such taxon that have been decoded in the framework of this study. Such data clearly pointed out the presence of intra-species micro-diversities that could have evolutionary significance contributing to phenotypical diversification by affecting protein domains. Specifically, two single nucleotide variations in the type II pullulanase gene sequence led to specific amino acid substitutions, possibly explaining the substantial differences in the growth performances and competition abilities observed in a multi-strain bioreactor culture simulating the vaginal environment. Accordingly, L. crispatus strains display different growth performances, suggesting that the colonisation and stable persistence in the female reproductive tract between the members of this taxon is highly variable. 相似文献
724.
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
725.
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
726.
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