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11.
Plant Molecular Biology Reporter - The original version of this article unfortunately contained some mistakes in article Title and Table 1.  相似文献   
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Electricity generation from microbial fuel cells which treat food processing wastewater was investigated in this study. Anaerobic anode and aerobic cathode chambers were separated by a proton exchange membrane in a two-compartment MFC reactor. Buffer solutions and food industry wastewater were used as electrolytes in the anode and cathode chambers, respectively. The produced voltage and current intensity were measured using a digital multimeter. Effluents from the anode compartment were tested for COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity. The maximum current density and power production were measured 527 mA/m2 and 230 mW/m2 in the anode area, respectively, at operation organic loading (OLR) of 0.364 g COD/l.d. At OLR of 0.182 g COD/l.d, maximum voltage and columbic efficiency production were recorded 0.475 V and 21%, respectively. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity were 86, 79, 73, 18, 68, 62, 30 and 58%, respectively. The results indicated that catalysts and mediator-less microbial fuel cells (CAML-MFC) can be considered as a better choice for simple and complete energy conversion from the wastewater of such industries and also this could be considered as a new method to offset wastewater treatment plant operating costs.  相似文献   
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Numerous studies have confirmed that cancer stem cells (CSCs) are more resistant to chemotherapy; however, there is a paucity of data exploring the effect of long-term drug treatment on the CSC sub-population. The purpose of this study was to investigate whether long-term doxorubicin treatment could expand the neuroblastoma cells with CSC characteristics and histone acetylation could affect stemness gene expression during the development of drug resistance. Using n-myc amplified SK-N-Be(2)C and non-n-myc amplified SK-N-SH human neuroblastoma cells, our laboratory generated doxorubicin-resistant cell lines in parallel over 1 year; one cell line intermittently treated with the histone deacetylase inhibitor (HDACi) vorinostat and the other without exposure to HDACi. Cells'' sensitivity to chemotherapeutic drugs, the ability to form tumorspheres, and capacity for in vitro invasion were examined. Cell-surface markers and side populations (SPs) were analyzed using flow cytometry. Differentially expressed stemness genes were identified through whole genome analysis and confirmed with real-time PCR. Our results indicated that vorinostat increased the sensitivity of only SK-N-Be(2)C-resistant cells to chemotherapy, made cells lose the ability to form tumorspheres, and reduced in vitro invasion and the SP percentage. CD133 was not enriched in doxorubicin-resistant or vorinostat-treated doxorubicin-resistant cells. Nine stemness-linked genes (ABCB1, ABCC4, LMO2, SOX2, ERCC5, S100A10, IGFBP3, TCF3, and VIM) were downregulated in vorinostat-treated doxorubicin-resistant SK-N-Be(2)C cells relative to doxorubicin-resistant cells. A sub-population of cells with CSC characteristics is enriched during prolonged drug selection of n-myc amplified SK-N-Be(2)C neuroblastoma cells. Vorinostat treatment affects the reversal of drug resistance in SK-N-Be(2)C cells and may be associated with downregulation of stemness gene expression. This work may be valuable for clinicians to design treatment protocols specific for different neuroblastoma patients.  相似文献   
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Glutaric aciduria type I (glutaryl-CoA dehydrogenase deficiency) is an inborn error of metabolism that usually manifests in infancy by an acute encephalopathic crisis and often results in permanent motor handicap. Biochemical hallmarks of this disease are elevated levels of glutarate and 3-hydroxyglutarate in blood and urine. The neuropathology of this disease is still poorly understood, as low lysine diet and carnitine supplementation do not always prevent brain damage, even in early-treated patients. We used a 3D in vitro model of rat organotypic brain cell cultures in aggregates to mimic glutaric aciduria type I by repeated administration of 1 mM glutarate or 3-hydroxyglutarate at two time points representing different developmental stages. Both metabolites were deleterious for the developing brain cells, with 3-hydroxyglutarate being the most toxic metabolite in our model. Astrocytes were the cells most strongly affected by metabolite exposure. In culture medium, we observed an up to 11-fold increase of ammonium in the culture medium with a concomitant decrease of glutamine. We further observed an increase in lactate and a concomitant decrease in glucose. Exposure to 3-hydroxyglutarate led to a significantly increased cell death rate. Thus, we propose a three step model for brain damage in glutaric aciduria type I: (i) 3-OHGA causes the death of astrocytes, (ii) deficiency of the astrocytic enzyme glutamine synthetase leads to intracerebral ammonium accumulation, and (iii) high ammonium triggers secondary death of other brain cells. These unexpected findings need to be further investigated and verified in vivo. They suggest that intracerebral ammonium accumulation might be an important target for the development of more effective treatment strategies to prevent brain damage in patients with glutaric aciduria type I.  相似文献   
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Tissue engineering, an immensely important field in contemporary clinical practices, aims at the repair or replacement of damaged tissues. The mathematical model proposed herein shows the distribution and growth of cells in their characteristic time in a 3D scaffold model. This study contributes to the progress of simulation techniques in static and dynamic cultures of bone tissue. Brinkman, nutrient transport, and cell growth equations are brought together to quantify the growth behavior of cells. However, when a static culture is being studied, the Brinkman equation is eliminated. The model was validated by experimental cell culture using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay and scanning electron microscopy. Then, static and dynamic cultures were compared to assess the cell density and cell distribution in the scaffold. Cell counting after 21 days of cell culture showed that the number of cells increased 42‐fold in static and 53.5‐fold in dynamic cultures, which was in good agreement with our model estimations (37‐fold increase in the number of cells in static and 49‐fold increase in dynamic cultures). In conclusion, our mathematical model could predict cell distribution and growth in the scaffold.  相似文献   
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Background and Purpose

In acute ischemic stroke (AIS) management, CT-based thrombus density has been associated with treatment success. However, currently used thrombus measurements are prone to inter-observer variability and oversimplify the heterogeneous thrombus composition. Our aim was first to introduce an automated method to assess the entire thrombus density and then to compare the measured entire thrombus density with respect to current standard manual measurements.

Materials and Method

In 135 AIS patients, the density distribution of the entire thrombus was determined. Density distributions were described using medians, interquartile ranges (IQR), kurtosis, and skewedness. Differences between the median of entire thrombus measurements and commonly applied manual measurements using 3 regions of interest were determined using linear regression.

Results

Density distributions varied considerably with medians ranging from 20.0 to 62.8 HU and IQRs ranging from 9.3 to 55.8 HU. The average median of the thrombus density distributions (43.5 ± 10.2 HU) was lower than the manual assessment (49.6 ± 8.0 HU) (p<0.05). The difference between manual measurements and median density of entire thrombus decreased with increasing density (r = 0.64; p<0.05), revealing relatively higher manual measurements for low density thrombi such that manual density measurement tend overestimates the real thrombus density.

Conclusions

Automatic measurements of the full thrombus expose a wide variety of thrombi density distribution, which is not grasped with currently used manual measurement. Furthermore, discrimination of low and high density thrombi is improved with the automated method.  相似文献   
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Leukemia is known as a progressive malignant disease, which destroys the blood-forming organs and results in adverse effects on the proliferation and development of leukocytes and their precursors in the blood and bone marrow. There are four main classes of leukemia including acute leukemia, chronic leukemia, myelogenous leukemia, and lymphocytic leukemia. Given that a variety of internal and external factors could be associated with the initiation and progression of different types of leukemia. One of the important factors is epigenetic regulators such as microRNAs (miRNAs) and long noncoding RNAs (ncRNA). MiRNAs are short ncRNAs which act as tumor suppressor (i.e., miR-15, miR-16, let-7, and miR-127) or oncogene (i.e., miR-155, miR-17-92, miR-21, miR-125b, miR-93, miR-143-p3, miR-196b, and miR-223) in leukemia. It has been shown that deregulation of these molecules are associated with the initiation and progression of leukemia. Hence, miRNAs could be used as potential therapeutic candidates in the treatment of patients with leukemia. Moreover, increasing evidence revealed that miRNAs could be used as diagnostic and prognostic biomarkers in monitoring patients in early stages of disease or after received chemotherapy regimen. It seems that identification and development of new miRNAs could pave to the way to the development new therapeutic platforms for patients with leukemia. Here, we summarized various miRNAs as tumor suppressor and oncogene which could be introduced as therapeutic targets in treatment of leukemia.  相似文献   
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