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801.
Supriyono Ai Takano Ryusei Kuwata Hiroshi Shimoda Upik K. Hadi Agus Setiyono Srihadi Agungpriyono Ken Maeda 《Microbiology and immunology》2019,63(8):328-333
Ticks are one of the arthropods that play an important role in the transmission of numerous pathogens to livestock and humans. We investigated the presence of tick‐borne bacteria in 23 Amblyomma varanense that fed on a water monitor (Varanus salvator) in Indonesia. Anaplasmataceae and borreliae were detected by PCR in 17.4% and 95.7% of ticks, respectively. “Candidatus Rickettsia sepangensis”, spotted fever group of Rickettsia, was detected in 21.7% of ticks. The water monitor is a common reptile that is widely encountered in city areas in Asian countries. Our results suggested that Am. varanense on water monitor in Indonesia harbored several kinds of bacteria. 相似文献
802.
The interaction of native calf thymus DNA with Diazinon, an organophophorus insecticide, in HEPES buffer at neutral pH, was monitored by UV absorption spectrophotometry, circular dichroism (CD), electrochemical technique, and fluorescence spectroscopy. UV spectra showed hyperchromicity and blue shift with the increase of Diazinon concentration. Fluorescence spectroscopy results indicated that the probable quenching mechanism of DNA-ethidium bromide (EB) fluorescence by Diazinon is a dynamic quenching procedure, because the Stern-Volmer quenching constant (K(SV)) increased with the temperature rising. Unchanging of the CD signal around 280 nm with increasing ratio of Diazinon to DNA is an important evidence for non-intercalative-binding mode of Diazinon with DNA. Stoichiometry measurement of the DNA-nDiazinon indicated that a stable 1:2 complex of DNA-Diazinon was formed under the selected conditions. The electrochemical study of the Diazinon-DNA interaction was carried out by incubation of DNA with Diazinon in the presence of varying amounts of selenium (Se). This technique revealed that Se is able to diminish the DNA damage effect of Diazinon. 相似文献
803.
Titto Sunil John Pradeep Kumar Yadav Devendra Kumar Sushil Kumar Singh Syed Hadi Hasan 《Luminescence》2020,35(6):913-923
In this study, we prepared carbon dots (CDs) from wheat bran via hydrothermal treatment at 180°C for 3 h. The prepared CDs showed blue‐green fluorescence under UV light. The fluorescence emission study of the CDs revealed that they showed maximum fluorescence emission at 500 nm. The prepared CDs showed a high quantum yield of 33.23%. Solvent‐dependent fluorescence emission analysis of the CDs was performed to study the variation in fluorescence emission characteristics with solvent polarity. The prepared CDs were conjugated with amoxicillin (AMX) to explore its potential for use as a drug delivery agent for AMX. The drug release profile of the CD–AMX conjugates was analyzed at different pH (5.0, 6.8 and 7.2) to study drug release kinetics. CD–AMX conjugates showed notable bacterial inhibition against Gram‐positive (S. aureus) and Gram‐negative (E. coli) strains with minimal cytotoxic effects, indicating its potential as a promising antibacterial drug delivery system. 相似文献
804.
Ghasemi Hadi Amini Mohammad Amin Pegah Atefeh Azizi Ebrahim Tayebinia Heidar Khanverdilou Shima Mousavibahar Seyed Habibollah Alizamir Aida 《Molecular biology reports》2020,47(9):6497-6505
Molecular Biology Reports - Reactive Oxygen Species Modulator 1 (ROMO1) plays a pivotal role in the regulation of mitochondrial structure integrity, and the production of reactive oxygen species... 相似文献
805.
Hadi Tadayyon Lakshmanan Sannachi Ali Sadeghi-Naini Azza Al-Mahrouki William T. Tran Michael C. Kolios Gregory J. Czarnota 《Translational oncology》2015,8(6):463-473
INTRODUCTION: Quantitative ultrasound parameters based on form factor models were investigated as potential biomarkers of cell death in breast tumor (MDA-231) xenografts treated with chemotherapy. METHODS: Ultrasound backscatter radiofrequency data were acquired from MDA-231 breast cancer tumor–bearing mice (n = 20) before and after the administration of chemotherapy drugs at two ultrasound frequencies: 7 MHz and 20 MHz. Radiofrequency spectral analysis involved estimating the backscatter coefficient from regions of interest in the center of the tumor, to which form factor models were fitted, resulting in estimates of average scatterer diameter and average acoustic concentration (AAC). RESULTS: The ∆AAC parameter extracted from the spherical Gaussian model was found to be the most effective cell death biomarker (at the lower frequency range, r2 = 0.40). At both frequencies, AAC in the treated tumors increased significantly (P = .026 and .035 at low and high frequencies, respectively) 24 hours after treatment compared with control tumors. Furthermore, stepwise multiple linear regression analysis of the low-frequency data revealed that a multiparameter quantitative ultrasound model was strongly correlated to cell death determined histologically posttreatment (r2 = 0.74). CONCLUSION: The Gaussian form factor model–based scattering parameters can potentially be used to track the extent of cell death at clinically relevant frequencies (7 MHz). The 20-MHz results agreed with previous findings in which parameters related to the backscatter intensity (i.e., AAC) increased with cell death. The findings suggested that, in addition to the backscatter coefficient parameter ∆AAC, biological features including tumor heterogeneity and initial tumor volume were important factors in the prediction of cell death response. 相似文献
806.
Anti‐angiogenic effects of CD73‐specific siRNA‐loaded nanoparticles in breast cancer‐bearing mice 下载免费PDF全文
807.
Khodaiyan F Razavi SH Emam-Djomeh Z Mousavi SM Hejazi MA 《Journal of microbiology and biotechnology》2007,17(2):195-201
This study investigated the effects of various culture parameters (carbon sources, temperature, initial pH of culture, NaCl concentration, and light) on the growth and canthaxanthin production by Dietzia natronolimnaea HS-1. The results showed that the most effective carbon source for growth and canthaxantin production was glucose, and the best pH and temperature were 7 and 31 degrees C, respectively. In addition, the biomass and canthaxanthin production increased in a medium without NaCl and in the presence of light. Under the optimized conditions, the maximum biomass, total carotenoid, and canthaxanthin production were 6.12 +/- 0.21 g/l, 4.51 +/- 0.20 mg/l, and 4.28 +/- 0.15 mg/l, respectively, in an Erlenmeyer flask system, yet increased to 7.25 g/l, 5.48 mg/l, and 5.29 mg/l, respectively, in a batch fermenter system. 相似文献
808.
Mohammad Foad Abazari Fatemeh Soleimanifar Mojdeh Amini Faskhodi Reyhaneh Nassiri Mansour Javad Amini Mahabadi Solmaz Sadeghi Hadi Hassannia Ehsan Saburi Seyed Ehsan Enderami Mohammad Mehdi Khani Shohreh Zare Karizi 《Journal of cellular physiology》2020,235(2):1155-1164
Blood transfusion or blood products, such as plasma, have a long history in improving health, but today, platelet-rich plasma (PRP) is used in various medical areas such as surgery, orthopedics, and rheumatology in many ways. Considering the high efficiency of tissue engineering in repairing bone defects, in this study, we investigated the combined effect of nanofibrous scaffolds in combination with PRP on the osteogenic differentiation potential of human induced pluripotent stem cells (iPSCs). Electrospinning was used for fabricating nanofibrous scaffolds by polyvinylidene fluoride/collagen (PVDF/col) with and without PRP. After scaffold characterization, the osteoinductivity of the fabricated scaffolds was studied by culturing human iPSCs under osteogenic medium. The results showed that PRP has a considerable positive effect on the biocompatibility of the PVDF/col nanofibrous scaffold when examined by protein adsorption, cell attachment, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. In addition, the results obtained from alkaline phosphatase activity and calcium content assays demonstrated that nanofibers have higher osteoinductivity while grown on PRP-incorporated PVDF/col nanofibers. These results were also confirmed while the osteogenic differentiation of the iPSCs was more investigated by evaluating the most important bone-related genes expression level. According to the results, it can be concluded that PVDF/col/PRP has much more osteoinductivity while compared with the PVDF/col, and it can be introduced as a promising bone bio-implant for use in bone tissue engineering applications. 相似文献
809.
Cyst‐Theca Relationship and Phylogenetic Position of Impagidinium caspienense Incubated from Caspian Sea Surface Sediments: Relation to Gonyaulax baltica and Evidence for Heterospory within Gonyaulacoid Dinoflagellates 下载免费PDF全文
Kenneth N. Mertens Yoshihito Takano Haifeng Gu Siamak Bagheri Vera Pospelova Anna J. Pieńkowski Suzanne A. G. Leroy Kazumi Matsuoka 《The Journal of eukaryotic microbiology》2017,64(6):829-842
We investigate the cyst‐theca relationship of Impagidinium caspienense. Through an incubation experiment, we succeeded in examining the motile stage. Additional molecular analysis of single‐cyst PCR (LSU and SSU rDNA) reveal that the cyst is related to the species Gonyaulax baltica Ellegaard et al. ( 2002 ). The ability of this species to belong to two types of cyst‐based genera (spiniferate and impagidinioid) suggests that environmental (particularly salinity) and not genetic factors explain the formation of both morphotypes by G. baltica, which provides evidence for heterospory in this species. The affiliation to G. baltica demonstrates that I. caspienense is not endemic to the Caspian Sea. The phylogenetic position of several other gonyaulacoid species is also documented: Impagidinium pallidum, Ataxiodinium choane, Pyxidinopsis psilata, Spiniferites belerius, and Spiniferites ramosus. The LSU and SSU rDNA based phylogenies suggest that the genera Impagidinium and Spiniferites are not monophyletic, and that P. psilata and A. choane are close to Gonyaulax verior and Gonyaulax polygramma, respectively. In addition, this study accentuates the importance of cyst morphology in the classification of the Gonyaulacales. 相似文献
810.
Evelyn Assadian Mohammad Hadi Zarei Ali Ghanadzadeh Gilani Mehrzad Farshin Hamid Degampanah Jalal Pourahmad 《Biological trace element research》2018,184(2):350-357
CuO nanoparticles (CuO-NPs) serve several important functions in human life, particularly in the fields of medicine, engineering, and technology. These nanoparticles have been utilized as catalysts, semiconductors, sensors, gaseous and solid ceramic pigments, and magnet rotatable devices. Further use for CuO-NPs has been employed in the pharmaceutical industry especially in the production of anti-microbial fabric treatments or prevention of infections caused by Escherichia coli and methicillin-resistant Staphylococcus aureus. Two key potential routes of exposure to CuO-NPs exist through inhalation and skin exposure. Toxicity of these nanoparticles has been reported in various studies; however, no study as of yet has investigated the complete cellular mechanisms involved in CuO-NPs toxicity on human cells. The aim of this study was to determine the cytotoxicity of CuO-NPs on human blood lymphocytes. Blood lymphocytes were obtained from healthy male subjects through the use of Ficoll polysaccharide subsequently by gradient centrifugation. The following parameters were assayed in blood lymphocytes after a 6-h incubation with different concentrations of CuO-NPs: cell viability, reactive oxygen species (ROS) formation, lipid peroxidation, cellular glutathione levels, and mitochondrial and lysosomal damage. Our results demonstrate that CuO-NPs, in particular, decreased cell viability in a concentration-dependent manner and the IC50 determined was 382 μM. CuO-NP cytotoxicity was associated with significant increase at intracellular ROS level and loss of mitochondrial membrane potential and lysosomal membrane leakiness. Hence, CuO-NPs are shown to effectively induce oxidative stress in addition to inflict damage on mitochondria and lysosomes in human blood lymphocytes. 相似文献