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Biological control of fungi causing root rot on sugar beet by native Streptomyces isolates (C and S2) was evaluated in this study. The dry weight and colony forming unit (CFU) of S2 and C increased when 300 mM NaCl was added to medium. The in vitro antagonism assays showed that both isolates had inhibitory effect against Rhizoctonia solani AG-2, Fusarium solani and Phytophthora drechsleri. In dual culture, Streptomyces isolate C inhibited mycelial growth of R. solani, F. solani and P. drechsleri 45%, 53% and 26%, respectively. NaCl treatment of medium increased biocontrol activity of soluble and volatile compounds of isolate C and S2. After salt treatment, growth inhibition of R. solani, F. solani and P. drechsleri by isolate C increased up to 59%, 70% and 79%, respectively. To elucidate the mode of antagonism, protease, chitinase, beta glucanase, cellulase, lipase and α-amylase activity and siderophore and salicylic acid (SA) production were evaluated. Both isolates showed protease, chitinase and α-amylase activity. Also, biosynthesis of siderophore was detectable for both isolates. Production of siderophore and activity of protease and α-amylase increased after adding salt for both isolates. In contrast, chitinase activity decreased significantly. Production of SA, beta glucanase and lipase by isolate S2 and biosynthesis of cellulase by isolate C were observed in presence and absence of NaCl. Soil treatment with Streptomyces isolate C inhibited root rot of sugar beet caused by P. drechsleri, R. solani and F. solani. Results of this study showed that these two Streptomyces isolates had potential to be utilized as biocontrol agent against fungal diseases especially in saline soils.  相似文献   
3.

Background

Tolerance to the analgesic effect of opioids is a pharmacological phenomenon that occurs after their prolonged administration. It has been shown that morphine-induced tolerance is associated with apoptosis in the central nervous system and neuroprotective agents which prevented apoptosis signaling could attenuate tolerance to the analgesic effects. On the other hand donepezil, an acetylcholinesterase inhibitor, has been reported to have neuroprotective effects. Therefore in this study, the effect of systemic administration of donepezil on morphine-induced tolerance and apoptosis in the rat cerebral cortex and lumbar spinal cord was evaluated. Various groups of rats received morphine (ip) and different doses of donepezil (0, 0.5, 1, 1.5 mg/kg/day). Nociception was assessed using tail flick apparatus. Tail flick latency was recorded when the rat shook its tail. For apoptosis assay other groups of rats received the above treatment and apoptosis was evaluated by in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) method.

Results

The results showed that administration of donepezil (0.5, 1, 1.5 mg/kg, ip) delayed the morphine tolerance for 9, 12 and 17 days, respectively. Furthermore pretreatment injection of donepezil attenuated the number of apoptotic cells in the cerebral cortex and lumbar spinal cord compared to the control group.

Conclusion

In conclusion, we found that systemic administration of donepezil attenuated morphine-induced tolerance and apoptosis in the rat cerebral cortex and lumbar spinal cord.  相似文献   
4.
Molecular Biology Reports - Metastasis is a major cause of death in Colorectal cancer (CRC) patients, and the Epithelial–mesenchymal transition (EMT) has been known to be a crucial event in...  相似文献   
5.

This study proposes a microfluidic device capable of separating monocytes from a type of cancer cell that is called T-cell acute lymphoblastic leukemia (RPMI-8402) in a continuous flow using negative and positive dielectrophoretic forces. The use of both the hydrodynamic and dielectrophoretic forces allows the separation of RPMI-8402 from monocytes based on differences in their intrinsic electrical properties and sizes. The specific crossover frequencies of monocytes and RPMI-8402 cells have been obtained experimentally. The optimum ranges of electrode pitch-to-channel height ratio at the cross sections with different electrode widths have been generally calculated by numerical simulations of the gradients of the electric field intensities and calculation their effective values (root-mean-square). In the device, the cell sorting has been conducted empirically, and then, the separation performance has been evaluated by analyzing the images before and after dielectrophoretic forces applied to the cells. In this work, the design of a chip with 77 μm gold–titanium electrode pitch was investigated to achieve high purity of monocytes of 95.2%. The proposed device can be used with relatively low applied voltages, as low as 16.5 V (peak to peak). Thus, the design can be used in biomedical diagnosis and chemical analysis applications as a lab-on-chip platform. Also, it can be used for the separation of biological cells such as bacteria, RNA, DNA, and blood cells.

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6.
Conductive nanofibrous scaffolds with that can conduct electrical current have a great potential in neural tissue engineering. The purpose of this study was to survey effects of electrical stimulation and polycaprolactone/polypyrrole/multiwall carbon nanotube (PCL/PPY/MWCNTs) fibrous scaffold on photoreceptor differentiation of trabecular meshwork mesenchymal stem cells (TM-MSCs). PCL/PPY/MWCNTs scaffold was made by electrospinning method. TM-MSCs were seeded on PCL/PPY/MWCNTs scaffold and stimulated with a potential of 115 V/m. Scanning electron microscopy, transmission electron microscopy, and FT-IR were used to evaluate the fabricated scaffold. Immunofluorescence and quantitative real-time polymerase chain reaction were used to examine differentiated cells. Scanning electron microscopy, transmitting electron microscopy, and FT-IR confirmed the creation of the composite structure of fibers. RT-qPCR analysis showed that the expression of rhodopsin and peripherin genes in electrically stimulated cells were significantly higher (5.7- and 6.23-fold, respectively; p ≤ 0.05) than those with no electrical stimulation. Collectively, it seems that the combination of PCL/PPY/MWCNTs scaffold, as a suitable conductive scaffold, and electrical stimulation could be an effective approach in the differentiation of stem cells in retinal tissue engineering.  相似文献   
7.
Community‐based participatory research (CBPR) was used to design and evaluate the effectiveness of a culturally relevant, science‐based intervention for the prevention of childhood obesity in the Commonwealth of the Northern Mariana Islands (CNMI), a US Commonwealth in the western Pacific. This cognitive behavioral lifestyle intervention, Project Familia Giya Marianas (PFGM), was offered during the 2005–2007 school years in all CNMI public elementary schools over eight sessions to primary caregivers of 3rd grade children (N = 407). A crossover design was utilized with half of the schools offering the intervention in the Fall term, while the other half delivered the sessions in the Spring term. The primary outcome measure was change in BMI z‐score. There was an intervention‐dependent effect on BMI z‐score, with program impact being a function of baseline BMI and the number of lessons attended. This effect was most apparent in students whose baseline BMI z‐score was in healthy range (≥5 to <85 percentile). In both Asian and Pacific Island groups, children whose caregivers completed 5–8 lessons experienced a significant change in BMI z‐score as compared to those with 0 lessons (P < 0.05). Research that integrates multidisciplinary and multimethod approaches is effective in identifying and/or devising solutions to address a complex condition such as childhood obesity. PFGM demonstrated that community participation can be successfully utilized in the development and implementation of childhood obesity prevention programs.  相似文献   
8.
With ever-increasing molecular information about colorectal cancer (CRC), there is an expectation to detect more sensitive and specific molecular markers for new advanced diagnostic methods that can surpass the limitations of current screening tests. Moreover, enhanced molecular pathology knowledge about cancer has led to the development of targeted therapies, designed to interfere with specific aberrant biological pathways in cancer. Furthermore, biotechnology has opened a new window in CRC diagnosis and treatment by introducing different application of antibodies, antibody fragments, non-Ig scaffold proteins, and aptamers in targeted therapy and drug delivery. This review summarizes the molecular diagnostic and therapeutic approaches in CRC with a focus on genetic and epigenetic alterations, protein and metabolite markers as well as targeted therapy and drug delivery by Ig-scaffold proteins, non-Ig scaffold proteins, nanobodies, and aptamers.  相似文献   
9.
The coronavirus disease 2019 (COVID-19) pandemic has become the most serious global public health issue in the past two years, requiring effective therapeutic strategies. This viral infection is a contagious disease caused by new coronaviruses (nCoVs), also called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Autophagy, as a highly conserved catabolic recycling process, plays a significant role in the growth and replication of coronaviruses (CoVs). Therefore, there is great interest in understanding the mechanisms that underlie autophagy modulation. The modulation of autophagy is a very complex and multifactorial process, which includes different epigenetic alterations, such as histone modifications and DNA methylation. These mechanisms are also known to be involved in SARS-CoV-2 replication. Thus, molecular understanding of the epigenetic pathways linked with autophagy and COVID-19, could provide novel therapeutic targets for COVID-19 eradication. In this context, the current review highlights the role of epigenetic regulation of autophagy in controlling COVID-19, focusing on the potential therapeutic implications.  相似文献   
10.
The WNT signaling is deregulated in most human colorectal cancers (CRC). Promoter methylation has been proposed as an alternative mechanism to inactivate genes in tumors. To gain insight into the methylation silencing of the WNT pathway during colorectal carcinogenesis, we examined the aberrant methylation profile of four genes, APC, Axin1, Axin2, and GSK3β in an unselected series of 112 sporadic colorectal tumors by methylation specific PCR. It has been suggested that the Axin2 C148T SNP is associated with the risk of developing certain types of cancers. To assess the contribution of Axin2 SNP to CRC susceptibility, we examined the Axin2 C148T genotype in CRC patients and 170 healthy controls by PCR-RFLP. The frequency of CRCs with at least one gene methylated was 18.75%. Promoter methylation of Axin2 and APC genes was detected in 7.1 and 11.9% of tumors, respectively. No aberrant methylation was found in Gsk3β and Axin1 gene in these tumor series. The methylation status of APC had no significant association with clinical parameters. But, promoter methylation of Axin2 was sex-related, occurring more frequently in females (P = 0.002). The frequency of Axin2 C148T genotypes were similar in patients and controls. Moreover, we observed no association between the Axin2 SNP and risk of CRC in patients stratified by age, sex, and smoking status. However, the heterozygote CT genotype was associated with a reduced CRC risk in distal patients compared with proximal patients (OR = 0.3; 95% CI 0.1–0.9, P = 0.04). Our findings indicate that Axin1 and GSK3β methylation play a minor role in colorectal carcinogenesis.  相似文献   
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