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Therapeutic Potential of Berberine in the Treatment of Glioma: Insights into Its Regulatory Mechanisms
Get PDFGlioma is known as one of the most common primary intracranial tumors accounting for four-fifths of malignant brain tumors. There are several biological pathways that play a synergistic, pathophysiological role in glioma, including apoptosis, autophagy, oxidative stress, and cell cycle arrest. According to previous rese arches, the drugs used in the treatment of glioma have been associated with significant limitations. Therefore, improved and/or new therapeutic platforms are required. In this regard, multiple flavonoids and alkaloids have been extensively studied in the treatment of glioma. Berberine is a protoberberine alkaloid with wide range of pharmacological activities, applicable to various pathological conditions. Few studies have reported beneficial roles of berberine in glioma. Berberine exerts its pharmacological functions in glioma by controlling different molecular and cellular pathways. We reviewed the existing knowledge supporting the use of berberine in the treatment of glioma and its effects on molecular and cellular mechanisms. © 2020, Springer Science+Business Media, LLC, part of Springer Nature
Benchmarking of Monte Carlo model of Siemens Oncor® linear accelerator for 18MV photon beam: Determination of initial electron beam parameters
No full textOBJECTIVE: This study aims to benchmark a Monte Carlo (MC) model of the 18 MV photon beam produced by the Siemens Oncor® linac using the BEAMnrc and DOSXYZnrc codes. METHODS: By matching the percentage depth doses and beam profiles calculated by MC simulations with measurements, the initial electron beam parameters including electron energy, full width at half maximum (spatial FWHM), and mean angular spread were derived for the 10×10 cm2 and 20×20 cm2 field sizes. The MC model of the 18 MV photon beam was then validated against the measurements for different field sizes (5×5, 30×30 and 40×40 cm2) by gamma index analysis. RESULTS: The optimum values for electron energy, spatial FWHM and mean angular spread were 14.2 MeV, 0.08 cm and 0.8 degree, respectively. The MC simulations yielded the comparable measurement results of these optimum parameters. The gamma passing rates (with acceptance criteria of 1/1 mm) for percentage depth doses were found to be 100 for all field sizes. For cross-line profiles, the gamma passing rates were 100, 97, 95, 96 and 95 for 5×5, 10×10, 20×20, 30×30 and 40×40 cm2 field sizes, respectively. CONCLUSIONS: By validation of the MC model of Siemens Oncor® linac using various field sizes, it was found that both dose profiles of small and large field sizes were very sensitive to the changes in spatial FWHM and mean angular spread of the primary electron beam from the bending magnet. Hence, it is recommended that both small and large field sizes of the 18 MV photon beams should be considered in the Monte Carlo linac modeling. © 2019-IOS Press and the authors. All rights reserved
The assessment of selected MiRNAs profile in HIV, HBV, HCV, HIV/HCV, HIV/HBV Co-infection and elite controllers for determination of biomarker
No full textBackground: The emerging relationship between microRNAs (miRNA) and viral-control is a topic of interest in the field of HIV. Host-genome might play an important role in the control of viremia. The aim of this study was to assess the specific miRNA profile that could contribute to the control of HIV replication in Elite Controllers. Materials and methods: The expression level of miRNAs was evaluated in 6 group patients, Elite Controller (EC), HIV, HBV, HCV, HIV-HBV-HIV-HCV, and healthy controls using real-time PCR assays. Also, liver enzymes (ALT and AST) and CD4 T cell count was assessed. Results: After adequate normalization, expression level of miRNAs was determined. The expression level of miR-146 in HIV/HCV co-infected patients was the highest in all groups. The miRNAs expression profile was significantly different in patient groups compared to control and EC. Some miRNA was significantly correlated with viral load and CD4 T cell count. Conclusions: The involvement of the mentioned miRNAs and correlation of these with viral and cellular parameters can justify the clinical outcome of all patient groups. The differentially expressed miRNA profile in patients suggests that miRNAs can be serve as biomarkers for risk of disease progression and differentiation of infections. Moreover, determining the profiles of miRNAs due to involvement of these in the pathogenesis of infection and manipulating these miRNAs could lead to opening a new gate to infection control. © 202
Anticancer Potential of Furanocoumarins: Mechanistic and Therapeutic Aspects
Get PDFCancer is one of the most extreme medical conditions in both developing and developed countries around the world, causing millions of deaths each year. Chemotherapy and/or radiotherapy are key for treatment approaches, but both have numerous adverse health effects. Furthermore, the resistance of cancerous cells to anticancer medication leads to treatment failure. The rising burden of cancer overall requires novel efficacious treatment modalities. Natural medications offer feasible alternative options against malignancy in contrast to western medication. Furanocoumarins' defensive and restorative impacts have been observed in leukemia, glioma, breast, lung, renal, liver, colon, cervical, ovarian, and prostate malignancies. Experimental findings have shown that furanocoumarins activate multiple signaling pathways, leading to apoptosis, autophagy, antioxidant, antimetastatic, and cell cycle arrest in malignant cells. Additionally, furanocoumarins have been shown to have chemo preventive and chemotherapeutic synergistic potential when used in combination with other anticancer drugs. Here, we address different pathways which are activated by furanocoumarins and their therapeutic efficacy in various tumors. Ideally, this review will trigger interest in furanocoumarins and their potential efficacy and safety as a cancer lessening agents
Design and characterization of flattening filter for high dose rate 192Ir and 60Co Leipzig applicators used in skin cancer brachytherapy: A Monte Carlo study
No full textPurpose: This study aimed to design optimal flattening filters for high dose rate (HDR) 192Ir and 60Co Leipzig applicators which are used to treat skin cancer. Materials and methods: MCNPX Monte Carlo code was used to design flattening filters for Leipzig applicators with inner diameters of 1, 2 and 3 cm. Then, their dosimetric characterizations such as dose distribution, dose profile, percentage depth dose, flatness, symmetry and homogeneity were evaluated in a 20 × 20 × 20 cm3 water phantom and compared with those without the flattening filter. Results: The flattening filter thickness varied from 0 mm (at the edge) to the maximum values of 0.30, 1.18, and 2.41 mm for the 192Ir Leipzig applicators of H1, H2, and H3 type, respectively. This quantity has maximum values of 0.96, 6.27, and 12.31 mm for the 60Co double wall applicators of D1, D2, and D3 type, respectively. The dose profile flatness values for the H1, H2, and H3 192Ir Leipzig applicators with the optimal flattening filters were 0.76, 1.26, and 1.85, respectively. Furthermore, the dose profile flatness values for the D1, D2, and D3 60Co double wall applicators with the optimal flattening filters were 1.11, 2.10 and 3.12, respectively. The dose profile symmetry values obtained from various source-applicator combinations were less than 1.02. Compared to the applicators without flattening filter, the homogeneity values for the H1, H2, and H3 192Ir Leipzig applicators with the optimal flattening filters were improved 1.68, 6.51, and 13.17 times, respectively, and for the D1, D2, and D3 60Co double wall applicators were improved 1.23, 6.21 and 9.54 times, respectively. Conclusion: The findings revealed that the inhomogeneous dose distribution resulted from the Leipzig applicators without the optimal flattening filter at the treatment surface could be improved by insertion of optimal lead flattening filters between the sources and treatment surface. © 2020 Elsevier Lt
The correlation between biofilm formation capability and antibiotic resistance pattern in Pseudomonas aeruginosa
Get PDFThe infections caused by Pseudomonas aeruginosa are life-threatening, due to high intrinsic antimicrobial resistance of this microorganism. The integrons and biofilm formation of P. aeruginosa have a significant role in antibiotic resistance. Therefore, this study aimed to evaluate antibiotic resistance pattern in Pseudomonas aeruginosa isolates with biofilm formation ability. This cross-sectional study from January 2017 to December 2017 was conducted on 78 isolates (58 clinical and 20 environmental) of P. aeruginosa recovered from the 547 samples (439 of clinical and 108 of environmental samples). The isolates were identified by phenotypic and genotypic tests. Kirby-Bauer disk diffusion method was used for susceptibility testing. The prevalence of class 1, 2 and 3 Integrons, rhlA, and lasB genes were determined using Polymerase Chain Reaction (PCR). Biofilm formation was determined using the microtiter plate method. Data analyzed using Stata 14 software and Chi-Square test. The most prevalent resistance was observed against Ticarcillin/Clavulanic Acid (55). Generally, 56.4 of isolates were producers of strong biofilm in both environmental and clinical isolates. The prevalence of strong biofilm producers in clinical isolates was more than environmental. A significant correlation was observed between Int1, Int2, and rhlA genes with biofilm formation capability (P = 0.02). Regarding >50 of both environmental and clinical isolates were producers of strong biofilm and because the source of clinical isolates may be from the environment, the necessary hygiene measurements should be taken. No significant correlation was observed between lasB gene with biofilm formation capability. © 2019 Elsevier Inc
Potential drugs used in the antibody�drug conjugate (ADC) architecture for cancer therapy
No full textCytotoxic small-molecule drugs have a major influence on the fate of antibody�drug conjugates (ADCs). An ideal cytotoxic agent should be highly potent, remain stable while linked to ADCs, kill the targeted tumor cell upon internalization and release from the ADCs, and maintain its activity in multidrug-resistant tumor cells. Lessons learned from successful and failed experiences in ADC development resulted in remarkable progress in the discovery and development of novel highly potent small molecules. A better understanding of such small-molecule drugs is important for development of effective ADCs. The present review discusses requirements making a payload appropriate for antitumor ADCs and focuses on the main characteristics of commonly-used cytotoxic payloads that showed acceptable results in clinical trials. In addition, the present study represents emerging trends and recent advances of payloads used in ADCs currently under clinical trials. © 2019 Wiley Periodicals, Inc
Knowledge and attitudes toward breastfeeding among female university students in Tabuk, Saudi Arabia
Get PDFBackground: In Saudi Arabia, rates and duration of breastfeeding are progressively declining. Objective: The objective of this study was to examine and describe the relationship between breastfeeding knowledge, attitudes, exposure, and intention of university female students in Saudi Arabia. Methods: This cross-sectional survey recruited 124 students who completed a self-reported questionnaire. The questionnaire included breastfeeding knowledge, attitude and exposure scales, and a breastfeeding intention scale. Descriptive and inferential statistics were used to analyze the data.Results: Participants had good breastfeeding knowledge (mean score of 9.51 ± 2.63) and positive attitudes (mean score of 42.0 ± 1.8). However, they had some misconceptions about eating certain foods during breastfeeding and that breastfeeding is painful. A significant relationship was found between breastfeeding knowledge and attitude (r = 0.896,P <0.01), breastfeeding knowledge and exposure (r = 0.191,P <0.01), breastfeeding knowledge and intention to breastfeed (Phi coefficient=0.179, P = 0.033), and breastfeeding attitudes and intention to breastfeed (Phi coefficient=0.177, P = 0.030). Participants' knowledge (OR=3.280;P <0.001) and attitude (OR=1.930;P <0.001) were identified as factors independently and positively associated with future breastfeeding intention. Conclusion: The study identified specific gaps in knowledge and attitudes that pertain mainly to breastfeeding in public and perceptions that breastfeeding is painful, formula feeding gives more freedom to the mother, and that dietary restrictions by the mother during breastfeeding are needed. These gaps should be addressed in future breastfeeding promotion
2019 Novel coronavirus (COVID-19) overview
No full textNovel coronaviruses (CoVs) are zoonotic pathogens, but the first human-to-human transmission has been reported. CoVs have the best known genome of all RNA viruses, and mutations in the genome have now been found. A pneumonia of unknown cause detected in Wuhan, China, was first reported to the WHO Country Office in China on 31 December 2019. This study aims to report early findings related to COVID-19 and provide methods to prevent and treat it. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature
Synthesis of novel Fe3O4@SiO2@Er2TiO5 superparamagnetic core�shell and evaluation of their photocatalytic capacity
No full textRare earth oxides Er2TiO5 photocatalysts supported on superparamagnetic Fe3O4@SiO2 core�shell nanostructures were prepared through a sol�gel method. The achieved magnetic nanostructures were characterized by a number of procedures such as XRD, FE-SEM, TEM, UV�Vis DRS, VSM and PL spectroscopy and then the activity of the magnetic nanostructures as a photocatalysts for the UV�Vis induced degradation of methyl orange was evaluated. The activity of Fe3O4@SiO2@Er2TiO5 were tested as photodegradation catalysts for removing methyl orange. Moreover, the effect of incorporating different amounts of erbium oxides in the photocatalysts was studied and it was found that the optimal amount of erbium oxide in terms of reaching the highest photocatalytic activity was 25 wt. © 2020, Springer Science+Business Media, LLC, part of Springer Nature