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11.
Song Mei Ling Kim Keun Tae Motamedi Gholam K. Cho Yong Won 《Sleep and biological rhythms》2019,17(4):447-454
Sleep and Biological Rhythms - Narcoleptics tend to have a low quality of life (QoL). Few studies have compared QoL in narcolepsy against other sleep disorders. The purpose of this study was to... 相似文献
12.
Addison WN Azari F Sørensen ES Kaartinen MT McKee MD 《The Journal of biological chemistry》2007,282(21):15872-15883
Inorganic pyrophosphate (PP(i)) produced by cells inhibits mineralization by binding to crystals. Its ubiquitous presence is thought to prevent "soft" tissues from mineralizing, whereas its degradation to P(i) in bones and teeth by tissue-nonspecific alkaline phosphatase (Tnap, Tnsalp, Alpl, Akp2) may facilitate crystal growth. Whereas the crystal binding properties of PP(i) are largely understood, less is known about its effects on osteoblast activity. We have used MC3T3-E1 osteoblast cultures to investigate the effect of PP(i) on osteoblast function and matrix mineralization. Mineralization in the cultures was dose-dependently inhibited by PP(i). This inhibition could be reversed by Tnap, but not if PP(i) was bound to mineral. PP(i) also led to increased levels of osteopontin (Opn) induced via the Erk1/2 and p38 MAPK signaling pathways. Opn regulation by PP(i) was also insensitive to foscarnet (an inhibitor of phosphate uptake) and levamisole (an inhibitor of Tnap enzymatic activity), suggesting that increased Opn levels did not result from changes in phosphate. Exogenous OPN inhibited mineralization, but dephosphorylation by Tnap reversed this effect, suggesting that OPN inhibits mineralization via its negatively charged phosphate residues and that like PP(i), hydrolysis by Tnap reduces its mineral inhibiting potency. Using enzyme kinetic studies, we have shown that PP(i) inhibits Tnap-mediated P(i) release from beta-glycerophosphate (a commonly used source of organic phosphate for culture mineralization studies) through a mixed type of inhibition. In summary, PP(i) prevents mineralization in MC3T3-E1 osteoblast cultures by at least three different mechanisms that include direct binding to growing crystals, induction of Opn expression, and inhibition of Tnap activity. 相似文献
13.
Rakhshan Kamran Dalouchi Fereshteh Sharifiaghdam Zeynab Safaei Atlasi Jahanshahi Fatemeh Azizi Yaser 《International journal of peptide research and therapeutics》2022,28(4):1-12
International Journal of Peptide Research and Therapeutics - Fibroblast growth factor 21 (FGF21) is a metabolic regulator with a wide range of biological functions. Although previous studies have... 相似文献
14.
Mansoureh Soleimani Fereshteh Golab Akram Alizadeh Sara Rigi Zeinab Nazarian Samani Gelareh Vahabzadeh Tahmineh Peirovi Maryam Sarbishegi Majid Katebi Fereshteh Azedi 《Journal of cellular physiology》2019,234(10):18720-18730
Electromagnetic fields (EMFs) are reported to interfere with chemical reactions involving free radical production. Coenzyme Q10 (CoQ10) is a strong antioxidant with some neuroprotective activities. The purpose of this study was to examine and compare the neuroprotective effects of EMF and CoQ10 in a mouse model of hippocampal injury. Hippocampal injury was induced in mature female mice (25–30 g), using an intraperitoneal injection of trimethyltin hydroxide (TMT; 2.5 mg/kg). The experimental groups were exposed to EMF at a frequency of 50 Hz and intensity of 5.9 mT for 7 hr daily over 1 week or treated with CoQ10 (10 mg/kg) for 2 weeks following TMT injection. A Morris water maze apparatus was used to assess learning and spatial memory. Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) tests were also performed for the histopathological analysis of the hippocampus. Antiapoptotic genes were studied, using the Western blot technique. The water maze test showed memory improvement following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Nissl staining and TUNEL tests indicated a decline in necrotic and apoptotic cell count following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Western blot study indicated the upregulation of antiapoptotic genes in treatment with CoQ10, as well as coadministration. Also, treatment with EMF had no significant effects on reducing damage induced by TMT in the hippocampus. According to the results, EMF had no significant neuroprotective effects in comparison with CoQ10 on hippocampal injury in mice. Nevertheless, coadministration of EMF and CoQ10 could improve the neuroprotective effects of CoQ10. 相似文献
15.
Mina Motamedi Atefeh Iranmanesh Azad Teimori Seyed Mahmoud Sadjjadi Saeid Nasibi 《Zeitschrift fur angewandte Ichthyologie》2019,35(2):558-569
The present study reports the occurrence of Contracaecum multipapillatum (Nematoda: Anisakidae) in an indigenous small killifish, Aphanius hormuzensis Teimori, Esmaeili, Hamidan, Reichenbacher, 2018 from Southern Iran and shows its histopathology. A total of 110 A. hormuzensis specimens were collected from Shur (Naband) River, Hormuzgan basin in Southern Iran and examined for their possible parasitic infections. Third‐stage larva of C. multipapillatum was extracted for the first time from the body cavity of 19 fish specimens (one male and 18 female) and identified by molecular and morphological methods. In comparison with non‐infected fishes, the melanomacrophage centers were detected in the tissue sections from liver, kidney and spleen of all the parasite infected fishes. To date, 16 parasites belong to nine families have been recorded from six Aphanius species (out of 15 known species) in Iran. Among them, eight and four parasites have been identified from A. vladykovi, and A. hormuzensis respectively. Since Aphanius species are living in different environments, therefore, they seem to be good hosts for the different types of parasites, and more new parasites are expected to be found in these fishes. 相似文献
16.
Somaye Shahraki Fereshteh Shiri Mostafa Heidari Majd Somaye Dahmardeh 《Journal of biomolecular structure & dynamics》2019,37(8):2072-2085
In this study, a new lanthanum (III)-amino acid complex utilizing cysteine has been synthesized and characterized. The anticancer activities of the prepared La(III) complex against MCF-7 cell lines were studied. Results of MTT assay showed that at all three incubation times, the cytotoxic effect of prepared La(III) complex on MCF-7 breast cancer cell lines displays a time- and dose-dependent inhibitory effects. The interactions of the La(III) complex with two whey proteins (bovine serum albumin, BSA, and Bovine β-lactoglobulin, βLG) have been explored by using spectroscopic and molecular dicking methods. The obtained results indicated that La(III) complex strongly quenched the fluorescence of two carrier proteins in static quenching mode and also, BSA hah stronger binding affinity toward studied complex than βLG whit binding constant values of KBSA-La?Complex?~?0.11?×?104 M?1 and KβLG-La?Complex?~?0.63?×?103 M?1 at 300 K. The thermodynamic parameters revealed the contribution of hydrogen bond and Vander Waals interactions in both systems. The distances of the La(III) complex whit whey proteins were calculated using Förster energy transfer theory and proved existence of the energy transfer between two proteins and prepared La(III) complex with a high probability. FT-IR and UV–Vis absorption measurements indicated that the binding of the La(III) to BSA and βLG may induce conformational and micro-environmental changes of the proteins. The docking results indicate that the La(III) complex bind to residues located in the site II of BSA and second site of βLG.
Communicated by Ramaswamy H. Sarma 相似文献
17.
Omid Jazayeri Setareh Farahmand Araghi Tahereh A. Aghajanzadeh Fereshteh Mir Mohammadrezaei 《Biomédica : revista del Instituto Nacional de Salud》2021,41(4):706
Introduction: Broccoli (Brassica oleracea) is well known for its properties as an anticancer, antioxidant, and scavenger of free radicals. However, its benefits in enhancing spermatogenesis have not been well established.Objective: To study broccoli aqueous extract effects on sperm factors and the expression of genes Catsper1, Catsper2, Arl4a, Sox5, and Sox9 in sperm factors in mice.Material and methods: Male mice were divided randomly into six groups: (1) Control; (2) cadmium (3 mg/kg of mouse body weight); (3) orally treated with 200 µl broccoli aqueous extract (1 g ml-1); (4) orally treated with 400 µl of broccoli aqueous extract; (5) orally treated with 200 broccoli aqueous extract plus cadmium, and (6) orally treated with 400 µl of broccoli aqueous extract plus cadmium. We analyzed the sperms factors and Catsper1, Catsper2, Arl4a, Sox5, and Sox9 gene expression.Results: An obvious improvement in sperm count and a slight enhancement in sperm motility were observed in mice treated with broccoli extract alone or with cadmium. Sperm viability was reduced by broccoli extract except for the 200 µl dose with cadmium, which significantly increased it. Interestingly, Arl4a gene expression increased in the 400 µl broccoli- treated group. Likewise, the Arl4a mRNA level in mice treated with cadmium and 200 µl of broccoli extract was higher than in the cadmium-treated mice. Furthermore, broccoli extract enhanced the mRNA level of Catsper2 and Sox5 genes in mice treated with 200 µl and 400 µl broccoli extract plus cadmium compared with the group treated solely with cadmium.Conclusion: The higher sperm count in broccoli-treated mice opens the way for the development of pharmaceutical products for infertile men. 相似文献
18.
19.
(S)(E)-2-{3-[3-[2-(7-chloro-2-quinolinyl)ethenyl]-phenyl]-3-hydroxypropyl} benzoic acid methyl ester,␣a key intermediate in the
synthesis of the anti-asthma drug, Montelukast, was prepared from the corresponding ketone (keto ester M) by microbial transformation.
The biotransforming organism, Microbacterium campoquemadoensis (MB5614), was discovered as a result of an extensive screening program and was used for the isolation and purification of
the responsible enzyme. The enzyme is a soluble cytoplasmic protein which was purified as a complex with a low-molecular-mass
molecule that had a visible-light absorption maximum at 460 nm. The purified enzyme has an apparent molecular mass of 60 kDa,
when denatured, and is isolated in the native state as an oligomer. The isolated enzyme requires NADPH for its activity and
reduces the keto ester M to the desired (S)-hydroxy ester with an enantiomeric excess greater than 95% at the optimum temperature of 30 °C and pH 8. The enzyme was
immobilized on oxirane-activated acrylamide beads with some loss of activity, but it was fully active in a two-phase (water/hexane
25:75) solvent system, both as a free solution and in an immobilized form.
Received: 31 October 1997 / Received revision: 8 January 1998 / Accepted: 24 January 1998 相似文献
20.
Sherry Towers Shehzad Afzal Gilbert Bernal Nadya Bliss Shala Brown Baltazar Espinoza Jasmine Jackson Julia Judson-Garcia Maryam Khan Michael Lin Robert Mamada Victor M. Moreno Fereshteh Nazari Kamaldeen Okuneye Mary L. Ross Claudia Rodriguez Jan Medlock David Ebert Carlos Castillo-Chavez 《PloS one》2015,10(6)