9 research outputs found
Comparision of Aqueous and Hydroalcoholic Extracts of Foeniculum Vulgare and Carum Copticum with Gentamicin on Escherichia Coli Strains: in Vitro Study
BACKGROUND AND OBJECTIVE: Due to bacterial resistance to antibiotics, new antibacterial agents is essential. In Persian medicine Fennel (Fuenoculum vulgare Mill.) and Ajwain (Carum copticum (L.) Benth. & Hook.f.) are recommended for the treatment of some infections. In this research, bacteriostatic and bactericidal effects of aqueous and hydroalcoholic extracts of fennel and Ajwain on E. coli were investigated.
METHODS: In an in-vitro study 30 clinical isolates of urine culture of children with urinary tract infection from Amirkola Pediatric Hospital in Babol and a standard sample were used. Antibacterial effects of 4 grouos including aqueous and hydroalcoholic extracts of fennel and Ajwain by measuring the diameter of the inhibition zone using disc diffusion (concentrations 16, 32, 64, 128, 256 and 512 mg/disc) and determination of Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentration (MBC) with Microdilution method was compared with Gentamicin (30mg/disc) as a positive control
FINDINGS: There was no significant difference in inhibition zone with Gentamicin at concentrations of 64, 128, 256, and 512 mg/disc in standard and clinical samples. At concentrations of 16 and 32, Gentamicin was significantly better. The extract of 512 mg/disc (12.93±2.66) of hydroalcoholic extract of Carum copticum was significantly better than 256 mg/disc (9.53±1) (p=0.002). The MIC and MBC for standard samples were 4 and 8, respectively, and for clinical samples 3.83±2.36 and 5.8 mg / ml, respectively. Other extracts were not able to inhibit the growth of Escherichia coli.
CONCLUSION: The results showed that the Hydroalcoholic extract of Carum copticum has bacteriostatic and bactericidal effects on standard and clinical isolates of Escherichia coli
Automated optimization of endoderm differentiation on chip.
Human induced pluripotent stem cells (hiPSCs) can serve as an unlimited source to rebuild organotypic tissues in vitro. Successful engineering of functional cell types and complex organ structures outside the human body requires knowledge of the chemical, temporal, and spatial microenvironment of their in vivo counterparts. Despite an increased understanding of mouse and human embryonic development, screening approaches are still required for the optimization of stem cell differentiation protocols to gain more functional mature cell types. The liver, lung, pancreas, and digestive tract originate from the endoderm germ layer. Optimization and specification of the earliest differentiation step, which is the definitive endoderm (DE), is of central importance for generating cell types of these organs because off-target cell types will propagate during month-long cultivation steps and reduce yields. Here, we developed a microfluidic large-scale integration (mLSI) chip platform for combined automated three-dimensional (3D) cell culturing and high-throughput imaging to investigate anterior/posterior patterns occurring during hiPSC differentiation into DE cells. Integration of 3D cell cultures with a diameter of 150 μm was achieved using a U-shaped pneumatic membrane valve, which was geometrically optimized and fluidically characterized. Upon parallelization of 32 fluidically individually addressable cell culture unit cells with a total of 128 3D cell cultures, complex and long-term DE differentiation protocols could be automated. Real-time bright-field imaging was used to analyze cell growth during DE differentiation, and immunofluorescence imaging on optically cleared 3D cell cultures was used to determine the DE differentiation yield. By systematically alternating transforming growth factor β (TGF-β) and WNT signaling agonist concentrations and temporal stimulation, we showed that even under similar DE differentiation yields, there were patterning differences in the 3D cell cultures, indicating possible differentiation differences between established DE protocols. The automated mLSI chip platform with the general analytical workflow for 3D stem cell cultures offers the optimization of in vitro generation of various cell types for cell replacement therapies
Pool boiling heat transfer of ferrofluids on structured hydrophilic and hydrophobic surfaces: the effect of magnetic field
The combined effect of external magnetic field and surface modification on boiling heat transfer of ferrofluids was investigated in this study. Experiments were performed on suspensions of Fe3O4 nanoparticles (volume fraction of 0.025% vf%) with and without presence of magnetic field on structured (surfaces with artificial cavities) hydrophilic and hydrophobic surfaces. Surface related effects such as the hole diameter, pitch size and surface wettability on boiling heat transfer were revealed using the high speed camera system. According to the obtained results, application of magnetic field enhanced boiling heat transfer. The effect of magnetic field was more pronounced on surfaces with larger pitch sizes. Magnetic field promoted bubble nucleation on the superheated surfaces by generating an additional force via Fe3O4 nanoparticles, resulting in enhanced bubblebubble interactions and coalescence. Furthermore, the surfaces with the larger cavity diameter performed better in terms of heat transfer. Scanning Electron Microscopy (SEM) images showed that as the cavity diameter decreased, deposited nanoparticles tended to completely fill the cavities on hydrophilic surfaces and thus deteriorate boiling heat transfer. On hydrophobic surfaces, deposition of nanoparticles led to a biphilic surface, thereby enhancing boiling heat transfer. As the cavity size increased, smaller portion of the cavities was filled with nanoparticles, and nucleation could still occur from the nucleation sites