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31.
Nasri  Elahe  Shoaei  Parisa  Vakili  Bahareh  Mirhendi  Hossein  Sadeghi  Somayeh  Hajiahmadi  Somayeh  Sadeghi  Alireza  Vaezi  Afsane  Badali  Hamid  Fakhim  Hamed 《Mycopathologia》2020,185(6):1077-1084
Mycopathologia - Although patients with severe immunodeficiency and hematological malignancies has been considered at highest risk for invasive fungal infection, patients with severe pneumonia due...  相似文献   
32.

Cinnamon (Cinnamomum verum and C. cassia) is a medicinal plant, widely-used as a culinary spice. It possesses various therapeutic effects and can slow down the progression of neurological disorders impressively. In this article, the effects of hydro-alcohol extract and essential oil of C. verum and C. cassia and its main bioactive component cinnamaldehyde, has been examined on 6-OHDA-exposed PC12 cells as an in vitro model of Parkinson's disease. The cytotoxicity and cell apoptosis has been induced by 6-OHDA in PC12 cells. The protective effect was determined by measuring cell viability, the amount of reactive oxygen species (ROS), and apoptosis. Cell viability and apoptosis were assessed using resazurin assay, flow cytometry of propidium iodide (PI) stained cells, and western blot analysis. 6-OHDA resulted in the death and apoptosis of cells while, pretreatment with the extract and essential oil of C. verum and C. cassia at 20 µg/ml and cinnamaldehyde at 5 and 10 µM for 24 h could significantly increase the viability (p?<?0.001), and decrease ROS content (p?<?0.05). Pretreatment with the extracts increased survivin and decreased cyt-c whereas, pretreatment with the essential oil decreased cyt-c, increased survivin, and reduced P-p44/42/p44/42 levels to a level near that of the related control. The extract and essential oil of C. verum and C. cassia can be effective against 6-OHDA cytotoxicity. It is suggested that, the synergistic effects of cinnamaldehyde and other components of extract and essential oil promote cinnamon’s medicinal properties.

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The extracellular matrix of different mammalian tissues is commonly used as scaffolds in the field of tissue engineering. One of these tissues, which has frequently been studied due to its structural and biological features, is the small intestine submucosal membrane. These research are mainly done on the porcine small intestine. However, a report has recently been published about a scaffold produced from the submucosal layer of the ovine small intestine. In the present study, ovine small intestine submucosal (OSIS) was decellularized in a modified manner and its histological, morphological, and biomechanical properties were studied. Decellularization was performed in two phases: physical and chemical. In this method, a chloroform-methanol mixture, enzymatic digestion, and a constant dose of sodium dodecyl sulfate (SDS) was used in the least agitation time and its histological property and biocompatibility were evaluated in the presence of adipose tissue-derived stem cells (ADSCs); furthermore, ADSCs were isolated with a simple method (modified physical washing non-enzymatic isolation). The results were showed that the use of OSIS could be effective and operative. Mechanical properties, histological structure and shape, and glycosaminoglycan content were preserved. In the SDS-treated group, more than 90% of the native cells of tissue were deleted, and also in this group, no toxicity was observed and cell proliferation was supported, compared to the untreated group. Therefore, our results indicate that ADSCs seeded on OSIS scaffold could be used as a new approach in regenerative medicine as hybrid or hydrogel application.  相似文献   
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Periodontitis is a complex disorder that affects a large number of human beings from different ethnic groups. This condition has been associated with dysregulation of a number of genes, among them are long noncoding RNAs (lncRNAs). In the current study, we assessed the expression of four lncRNAs (BDNF-AS, MIAT, MIR137HG, and PNKY) as well as BDNF in the peripheral blood and gingival tissues obtained from patients with periodontitis and healthy subjects. The expression of BDNF was significantly lower in blood samples of male patients with periodontitis compared with male controls (posterior β of RE = −4.754, p = .048). However, there was no significant difference in the expression of BDNF in tissue samples from the cases and controls. The expression of BDNF-AS was significantly lower in the tissue samples of patients compared with control tissue samples (posterior β of RE = −2.151, p = .019). Such an expression difference was detected between male subgroups as well (posterior β of RE = −3.679, p = .009). However, expression of this lncRNA was not different in blood samples obtained from patients compared with healthy subjects. The expression of PNKY was significantly higher in tissue samples obtained from female patients compared with sex-matched controls (posterior β of RE = 6.23, p = .037). Blood levels of this lncRNA were not different between cases and controls. There was no significant difference either in the tissue expression or in blood expression of MIR137HG or MIAT between cases and controls. The current study indicates the putative role of BDNF, BDNF-AS, and PNKY in the pathophysiology of periodontitis and potentiates these genes as candidates for functional studies.  相似文献   
37.

Background

The secretory activity of Sertoli cells (SC) is dependent on ion channel functions and protein synthesis and is critical to ongoing spermatogenesis. The aim of this study was to investigate the mechanism of action associated with a non-metabolizable amino acid [14C]-MeAIB (α-(methyl-amino)isobutyric acid) accumulation stimulated by T4 and the role of the integrin receptor in this event, and also to clarify whether the T4 effect on MeAIB accumulation and on Ca2+ influx culminates in cell secretion.

Methods

We have studied the rapid and plasma membrane initiated effects of T4 by using 45Ca2+ uptake and [45C]-MeAIB accumulation assays, respectively. Thymidine incorporation into DNA was used to monitor nuclear activity and quinacrine to analyze the secretory activity on SC.

Results

The stimulation of MeAIB accumulation by T4 appears to be mediated by the integrin receptor in the plasma membrane since tetrac and RGD peptide were able to nullify the effect of this hormone. In addition, T4 increases extracellular Ca2+ uptake and Ca2+ from intracellular stocks to enhance nuclear activity, but this genomic action seems not to influence SC secretion mediated by T4. Also, the cytoskeleton and ClC-3 chloride channel contribute to the membrane-associated responses of SC.

Conclusions

T4 integrin receptor activation ultimately determines the plasma membrane responses on amino acid transport in SC, but it is not involved in calcium influx, cell secretion or the nuclear effect of the hormone.

General significance

The integrin receptor activation by T4 may take a role in plasma membrane processes involved in the male reproductive system.  相似文献   
38.
In this study, Torulaspora delbrueckii alone and in combination with silicon were evaluated for the control of apple blue mould disease caused by Penicillium expansum. In vitro, the antagonistic effects of T. delbrueckii in controlling mycelial growth of P. expansum on potato-dextrose-agar (PDA) in dual cultures, and the growth of P. expansum alone with cell-free metabolites and volatile components of T. delbrueckii were assayed. In vitro, to evaluate the direct effect of silicon on mycelial growth of pathogen, silicon at different concentrations (0.2, 0.4, 0.6, 1 and 2% (wt./vol.)) was added to PDA medium. Silicon at 0.6% (wt./vol.) and above concentrations completely inhibited the mycelial growth of P. expansum. However, it had no significant effect on population dynamics of yeast in vitro and in apple wounds. In vivo, silicon at 0.2 and 1% (wt./vol.) in combination with antagonistic yeast (1 × 108 cell/ml) was a more effective approach to reduce the lesion diameter of blue mould decay of apples than the application of silicon or T. delbrueckii alone at 20 and 4°C, respectively.  相似文献   
39.
In this study, antagonistic yeast Candida membranifaciens was combined with different concentrations of silicon (Si; 0, 0.1, 0.3 and 0.5% wt/vol) to evaluate the control of blue mold of apple in storage at 20°C and 5°C. Preliminary studies showed that Si at 0.6% or above inhibited mycelial growth of pathogens significantly in vitro. In vitro studies showed that Si at 0.1% had lower effect on yeast growth. In vivo studies showed that combination of different concentrations of Si with C. membranifaciens improved the efficacy of yeast in control of disease better than Si and yeast alone (P < 0.05). Our result showed that the effective concentration of Si is varied based on pathogen isolates and temperature, so that the most effective concentration of Si was 0.5% for isolate P2 at 20°C and 0.5% and 0.1% for isolates P1 and P2 at 5°C.  相似文献   
40.
In this study, we have investigated inhibitory capacity of ethyl acetate, total oligomer flavonoid (TOF), aqueous extracts and beta amyrin acetate, a triterpene isolated from ethyl acetate extract obtained from leaves of Daphne gnidium, on mouse melanoma (B16-F0 and B16-F10 cells) proliferation. Influence of these products on percentage cell distribution in cycle phases and melanogenesis was also studied. Cell viability was determined using the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and flow cytometry was used to analyse effects of tested compounds on progression through the cell cycle. In addition, amounts of melanin and tyrosinase were measured spectrophotometrically at 475 nm. Ethyl acetate, TOF and aqueous extracts exhibited significant anti-proliferative activity after incubation with the two types of tumour skin cells B16-F0 and B16-F10. Furthermore, cell cycle analysis revealed that cells treated with ethyl acetate and TOF extracts were arrested predominantly in G2-M phase. Ethyl acetate extract has also the ability to enhance melanogenesis and tyrosinase activity of B16-F0 melanoma cells. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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