107 research outputs found
The bipartite Ramsey numbers
For the given bipartite graphs , the multicolor bipartite
Ramsey number is the smallest positive integer
such that any -edge-coloring of contains a monochromatic subgraph
isomorphic to , colored with the th color for some . We
compute the exact values of the bipartite Ramsey numbers for
Fully automated clinical target volume segmentation for glioblastoma radiotherapy using a deep convolutional neural network
Purpose: Target volume delineation is a crucial step prior to radiotherapy planning in radiotherapy for glioblastoma. This step is performed manually, which is time-consuming and prone to intra- and inter-rater variabilities. Therefore, the purpose of this study is to evaluate a deep convolutional neural network (CNN) model for automatic segmentation of clinical target volume (CTV) in glioblastoma patients. Material and methods: In this study, the modified Segmentation-Net (SegNet) model with deep supervision and residual-based skip connection mechanism was trained on 259 glioblastoma patients from the Multimodal Brain Tumour Image Segmentation Benchmark (BraTS) 2019 Challenge dataset for segmentation of gross tumour volume (GTV). Then, the pre-trained CNN model was fine-tuned with an independent clinical dataset (n = 37) to perform the CTV segmentation. In the process of fine-tuning, to generate a CT segmentation mask, both CT and MRI scans were simultaneously used as input data. The performance of the CNN model in terms of segmentation accuracy was evaluated on an independent clinical test dataset (n = 15) using the Dice Similarity Coefficient (DSC) and Hausdorff distance. The impact of auto-segmented CTV definition on dosimetry was also analysed. Results: The proposed model achieved the segmentation results with a DSC of 89.60 ± 3.56% and Hausdorff distance of 1.49 ± 0.65 mm. A statistically significant difference was found for the Dmin and Dmax of the CTV between manually and automatically planned doses. Conclusions: The results of our study suggest that our CNN-based auto-contouring system can be used for segmentation of CTVs to facilitate the brain tumour radiotherapy workflow
Protective effects of hydroalcoholic extract of Ferulago angulata against gentamicin-induced nephrotoxicity in rats
Gentamicin can lead to acute tubular injury and kidney dysfunction. This study aimed to evaluate the effect of Ferulago angulata on kidney function and other markers in rats with gentamicin-induced nephrotoxicity. Materials and Methods. Forty-eight male Wistar rats were divided into the following groups: group 1, the controls; group 2, rats receiving gentamicin (120 mg/kg body weight per day, intraperitoneal) for 7 days without treatment; groups 3, 4 and 5, rats receiving gentamicin for 7 days and oral treatment with 200 mg/kg, 400 mg/kg, and 800 mg/kg body weight per day of Ferulago angulate extract, respectively. Measurements included serum levels of creatinine, urea, uric acid, lipids, ferric-reducing antioxidant power, and protein carbonyl; kidney and serum levels of malondialdehyde; and serum and renal levels of tumor necrosis factor-α. Histopathology of kidney tissue was examined as well as renal catalase, superoxide dismutase, and vitamin C. Results. Compared to treatment with gentamicin only, treatment with Ferulago angulata resulted in a significantly higher high-density lipoprotein cholesterol, ferric-reducing antioxidant plasma, renal catalase, superoxide dismutase, and vitamin C levels. It was also associated with significantly lower serum levels of creatinine, urea, uric acid, malondialdehyde, protein carbonyl, tumor necrosis factor-α, total cholesterol, triglyceride, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol. Ferulago angulate was linked with a lower renal gene expression of tumor necrosis factor-α. Conclusions. The present study suggests that Ferulago angulate extract has protective effects against nephrotoxicity due to gentamicin
Investigation on the deletion and duplication of PMP22 gene in patients with Charcot-Marie-Tooth using Real-time PCR in Chaharmahal and Bakhtiari and Isfahan Provinces
Background and aims: Charcot-Marie-Tooth (CMT) is a common sensory-motor polyneuropathy with a prevalence of 1/2500. It is divided into different subgroups and has various hereditary patterns. Among the different subgroups of CMT, type 1A is the most prevalent form of the disease, which is created due to the duplication of the PMP22 gene. In patients has a deletion in the PMP22 gene, the hereditary neuropathic disease is known to be liable to pressure. The aim of this study was to identify the patients affected by the disease with the new, simple, and fast qPCR method and to investigate the appropriateness of this method in evaluating these types of mutations.
Methods: In this analytical-descriptive study (code:IR.SKUMS.REC.1394.152), gene duplication and deletion in the patients were studied using the Excel software. The blood samples of 15 families afflicted with CMT and 49 healthy individuals were collected in EDTA anticoagulant tubes and analyzed. DNA extraction and quantitative real-time PCR method were applied for the PMP22 gene as the target gene and the albumin gene as the internal control gene.
Results: Two genes were compared in each patient, and it was found that 46% of the subjects had duplication in the PMP22 gene.
Conclusion: The qPCR method is an easy and fast way to detect gene duplication and deletion in CMT patients. It does not require any statistical software and can be performed without needing for parental DNA. In addition, the results of this study are consistent with the results of various studies in some countries of the world where the highest levels of deletion and duplication in PMP22 gene are seen.
Keywords: CMT1A, PMP22 gene, Quantitative real-time PC
Effects of cumin extract on serum lipid profile and total antioxidant capacity in rats receiving high-fat diet
Background and Objective: Obesity is a serious global health problem. In this study the effects of cumin extract in rats receiving high fat diets were investigated and compared with metformin. Materials and Methods: Eighty rats were divided into two sets of forty and each set was divided into four groups: the first group was a control group, the second group received a high fat diet, the third group received a high fat diet with metformin and forth group received a high fat diet with an extract of cumin. After treatment Malondialdehyde (MDA), catalase and antioxidant capacity (FRAP) were measured. Results: In the first set, the weight of the second group increased in comparison to the group receiving a normal diet. Weight in rats receiving metformin in combination with cumin extract decreased compared to the second group. MDA in rats belonging to the second group showed a greater increase compared to the control group, however FRAP was decreased. Results gathered from the second set are as follows: MDA increased in rats belonging to the second group more than the control group but, FRAP and catalase declined. MDA and catalase increased in the metformin group compared to the second group. PON1 activity, catalase and FRAP in cumin receiving rats increased compared to the second group and MDA declined. Conclusion: The results of the present study suggest that cumin extract has better protective effects against oxidative stress in high fat diet and obesity in comparison to metformin in rats
Investigating the effects of chemical modification of clay nanoparticles on thermal degradation and mechanical properties of TPU/nanoclay composites
Thermoplastic polyurethane (TPU)/clay nanocomposites were prepared via a melt-compounding method using ester type TPU and two different modified organoclays (Cloisite 30B and Cloisite 15A) in different contents. The Effects of the chemical structure and content of the nanoclays on the thermal degradation and mechanical properties of TPU were also investigated. The effect of structural modification on dispersion during melt compounding has been studied by XRD and FTIR analysis. Barrier effect formation and thermal stability in both nanocomposites containing different nanoparticle content have been studied. The effect of chemical modification of the nanoparticles on mechanical properties in all contents has been investigated. The XRD results show that better dispersion near the exfoliated structure obtained for cloisite 30B is due to good interaction via hydrogen bonding between the TPU chains and layered silicate. A high content of the nanoparticles leads to disordering of soft and hard segments in the TPU chains, which is confirmed by FTIR. Mechanical properties analysis shows that the TPU/Cloisite 30B nanocomposites have higher modulus and tensile strength as well as elongation at break by the addition of 2% in both cloisite 30B (C30B) and cloisite 15A (C15A) than other contents of nanoclays
Cytotoxicity effect of pineapple extract on breast cancer cells (4T1)
Aqueous extract of pineapple (Bromelain) is used in medicine. Bromelain has anticancer effect on leukemia, lymphoma, sarcoma and melanoma. The purpose of this study was to evaluate the anticancer effect of bromelain on mouse breast cancer (4T1) cells under in-vitro conditions. Methods: Mouse breast cancer (4T1) cells were incubated with different concentrations of the bromelain for 2, 24, 48 and 72 hours. The growth-inhibitory was investigated via 3 (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) assay. Kruskal-Wallis and Dunn’s tests were used to evaluate the statistical significance of the difference between the experimental and control groups. Findings: Bromelain significantly inhibited proliferation of 4T1 cells in a concentration-dependent manner. In all concentrations, cell viability decreased with respect to the control incubated cells in the absence of extract (P < 0.05). Bromelain exerted highest antiproliferative effects on 4T1 cells for concentrations of 100, 200, 300, 400 and 600 µg/ml (P < 0.05) for 24, 48 and 72 hours, while cell viability increased for times shorter than 2 hours. The half maximal inhibitory concentration (IC50) value of 142.6 g/ml was obtained from treating 4T1 cells. Conclusion: Results showed that bromelain has cytotoxic effects on the growth and proliferation of 4T1 cells for 24, 48 and 72 hours of incubation. This study is ongoing to assess the extract mechanism of action
Antidepressant-like effect of essential oil of Lavandula angustifolia Mill and Citrus bigaradia Duh with forced swimming test in reserpinized mice Balb/C.
Background: Levandula angustifolia and Citrus aurantium essential oils possess phenolic
compounds and in Iranian traditional medicine are commonly used as sedative. The aim of
this study was to evaluate the antidepressant activities of Levandula angustifolia and Citrus
bigaradia in adult reserpinized mice.
Methods: In this experimental study, mice were divided into 10 groups of 8 mice each,
including: Group 1, control group received normal saline. Group 2, was treated reserpine (5
mg/kg, IP). Group 3, 4, 5 and 6 were treated with reserpine (5 mg/kg, IP) and four Citrus
aurantium different doses (25, 50, 100, 200 mg/kg). Group 7, 8 and 9 were treated with
reserpine (5 mg/kg, IP) and three Levandula angustifolia doses (25, 50, 100 mg/kg). Group
10 was treated with reserpine (5 mg/kg, IP) and imipramine (15 mg/kg). In all groups the
forced swimming test was done and the level of malondialdehyde (MDA) in brain tissue was
measured to estimate the oxidative stress status. Data were analyzed by one-way ANOVA
and Tukey post hoc test.
Results: Levandula angustifolia, Citrus aurantium and imipramine in reserpinized mice
caused the mice to spend less time in the forced swimming test, compared to the control
group (p<0.01). Also Citrus aurantium with dose of 50 and 100 mg/kg and Lavandula
angustifolia with dose of 25 and 50 mg/kg in reserpinized mice reduced immobility time and
levels of MDA compared the control group (p<0.01).
Conclusion: Lavander and Citrus aurantium essential oils have considerable antidepressant
activity which might be attributed to their antioxidant effects
Efficacy and safety of sofosbuvir in the treatment of SARS-CoV-2: an open label phase II trial
Objective: Despite the worldwide spread of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), an effective specific antiviral treatment for coronavirus disease of 2019 (COVID-19) is yet to be identified .We did this study to investigate the safety and efficacy of sofosbuvir as antiviral therapy among hospitalized adult patients with SARS-CoV-2. Methods: Patients were randomized into intervention arm receiving sofosbuvir or comparison arm receiving usual antiviral agents in addition to standard of care. The primary end point of the study was clinical recovery as defined by normal body temperature and normal oxygen saturation. The main secondary outcome was all-cause mortality during the admission in hospital or within 14 days after discharge if applicable. Reports of severe adverse events were observed in the intervention arm. Results: Fifty-seven patients enrolled into either the clinical trial arm (n=27) or the comparison arm (n=30). Primary outcome was achieved by 24 (88.9%) and 10 (33.3%) in the intervention and comparison arms, respectively. Median hospital length of stay was significantly shorter in the intervention arm (10 days [IQR: 5-12] vs. 11.5 days [IQR: 8.5-17.75], P = 0.016). All-cause mortality was two and thirteen in intervention and comparison groups, respectively. No serious adverse events were reported by the patients receiving sofosbuvir during the study. Conclusion: Among patients hospitalized with SARS-CoV-2, those who received sofosbuvir had more clinical recovery rate and had a shorter hospital length of stay than those who received usual antiviral agents in the study and these differences were statistically significant
Evaluation of minerals, phenolics and anti-radical activity of three species of Iranian berberis fruit
The amounts of substances together with nutritional and medicinal properties of fruits from Berberidaceae family vary between the plant species. Aluminum chloride colorimetric assay was used for flavonoids determination in 250 g of dried fruit. The Folin-Ciocalteau method was used to determine the total phenolic compound contents. The free radical-scavenging activity was examined by stable 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) assay. The level of total phenol in different Berberis Ecotypes was 241.5 mg/g for Black berberis khorasanica, 296.8 mg/g for Black berberis bakhtiarica and 157.5 mg/g for Red berberis khorasanica. Furthermore, anti-radical activities (IC50) of these three Iranian Berberis species were 221.1, 58.38 and 123.2 μg/mL respectively. The level of flavonol in Black berberis khorasanica was approximately 2.42-fold higher than Black berberis bakhtiarica and 5.49-fold higher than Red berberis khorasanica. The content of flavonoids in Black berberis bakhtiarica was aproximately 2 times more than its level in Black berberis khorasanica and 3.55 times more than its level in Red berberis khorasanica. The highest amount of phenol and total phenols were observed in Black berberis bakhtiarica as its anti-radical activity was approximately 3.8 times more than Black berberis khorasanica and 2.1 times more than Red Berberis khorasanica. We showed high level of antioxidant compounds in Black berberis bakhtiarica. Considering the rate of elements and compounds in three Iranian Berberis ecotypes and based on their antioxidant and anti-radical effects, the berberis can be of benefit to oppose free radicals in the body
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