OBJECTIVES: The emergence of resistant bacteria is being increasingly reported around the world, potentially threatening millions of lives. Amongst resistant bacteria, methicillin-resistant Staphylococcus aureus (MRSA) is the most challenging to treat. This is due to emergent MRSA strains and less effective traditional antibiotic therapies to Staphylococcal infections. The use of bacteriophages (phages) against MRSA is a new, potential alternate therapy. In this study, morphology, genetic and protein structure of lytic phages against MRSA have been analysed. METHODS: Isolation of livestock and sewage bacteriophages were performed using 0.4 μm membrane filters. Plaque assays were used to determine phage quantification by double layer agar method. Pure plaques were then amplified for further characterization. Sulfate-polyacrylamide gel electrophoresis and random amplification of polymorphic DNA were run for protein evaluation, and genotyping respectively. Transmission electron microscope was also used to detect the structure and taxonomic classification of phage visually. RESULTS: Head and tail morphology of bacteriophages against MRSA were identified by transmission electron microscopy and assigned to the Siphoviridae family and the Caudovirales order. CONCLUSION: Bacteriophages are the most abundant microorganism on Earth and coexist with the bacterial population. They can destroy bacterial cells successfully and effectively. They cannot enter mammalian cells which saves the eukaryotic cells from lytic phage activity. In conclusion, phage therapy may have many potential applications in microbiology and human medicine with no side effect on eukaryotic cells.
Agar ; Bacteria ; Bacteriophages ; Caudovirales ; Classification ; DNA ; Electrophoresis ; Eukaryotic Cells ; Head ; Humans ; Livestock ; Membranes ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Methods ; Microscopy, Electron, Scanning Transmission ; Microscopy, Electron, Transmission ; Sewage ; Siphoviridae ; Staphylococcal Infections ; Tail

PURPOSE: Several studies have shown that the oral cavity is a secondary location for Helicobacter pylori colonization and that H. pylori is associated with the severity of periodontitis. This study investigated whether H. pylori had an effect on the periodontium. We established an invasion model of a standard strain of H. pylori in human periodontal ligament fibroblasts (hPDLFs), and evaluated the effects of H. pylori on cell proliferation and cell cycle progression. METHODS: Different concentrations of H. pylori were used to infect hPDLFs, with 6 hours of co-culture. The multiplicity of infection in the low- and high-concentration groups was 10:1 and 100:1, respectively. The Cell Counting Kit-8 method and Ki-67 immunofluorescence were used to detect cell proliferation. Flow cytometry, quantitative real-time polymerase chain reaction, and western blots were used to detect cell cycle progression. In the high-concentration group, the invasion of H. pylori was observed by transmission electron microscopy. RESULTS: It was found that H. pylori invaded the fibroblasts, with cytoplasmic localization. Analyses of cell proliferation and flow cytometry showed that H. pylori inhibited the proliferation of periodontal fibroblasts by causing G2 phase arrest. The inhibition of proliferation and G2 phase arrest were more obvious in the high-concentration group. In the low-concentration group, the G2 phase regulatory factors cyclin dependent kinase 1 (CDK1) and cell division cycle 25C (Cdc25C) were upregulated, while cyclin B1 was inhibited. However, in the high-concentration group, cyclin B1 was upregulated and CDK1 was inhibited. Furthermore, the deactivated states of tyrosine phosphorylation of CDK1 (CDK1-Y15) and serine phosphorylation of Cdc25C (Cdc25C-S216) were upregulated after H. pylori infection. CONCLUSIONS: In our model, H. pylori inhibited the proliferation of hPDLFs and exerted an invasive effect, causing G2 phase arrest via the Cdc25C/CDK1/cyclin B1 signaling cascade. Its inhibitory effect on proliferation was stronger in the high-concentration group.
Blotting, Western ; CDC2 Protein Kinase ; Cell Count ; Cell Cycle ; Cell Proliferation ; Coculture Techniques ; Colon ; Cyclin B1 ; Cytoplasm ; Fibroblasts ; Flow Cytometry ; Fluorescent Antibody Technique ; G2 Phase ; Helicobacter pylori ; Helicobacter ; Humans ; Methods ; Microscopy, Electron, Transmission ; Mouth ; Periodontal Ligament ; Periodontitis ; Periodontium ; Phosphorylation ; Real-Time Polymerase Chain Reaction ; Serine ; Tyrosine

Adult ; Animals ; Ecthyma, Contagious ; diagnosis ; virology ; Female ; Humans ; Microscopy, Electron, Transmission ; methods ; Young Adult

We proposed a new stitching method based on sift features to obtain an enlarged view of transmission electron microscopic (TEM) images with a high resolution. The sift features were extracted from the images, which were then combined with fitted polynomial correction field to correct the images, followed by image alignment based on the sift features. The image seams at the junction were finally removed by Poisson image editing to achieve seamless stitching, which was validated on 60 local glomerular TEM images with an image alignment error of 62.5 to 187.5 nm. Compared with 3 other stitching methods, the proposed method could effectively reduce image deformation and avoid artifacts to facilitate renal biopsy pathological diagnosis.
Algorithms ; Artifacts ; Humans ; Image Processing, Computer-Assisted ; methods ; Kidney Glomerulus ; ultrastructure ; Microscopy, Electron, Transmission ; methods

The gamma-cyclodextrin-folate (gamma-CD/FA) inclusion-coated CdSe/ZnS quantum dots (QDs) with folate-receptor (FR) targeted were synthesized by simple and convenient sonochemical method. The products were studied using Fourier transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR), utraviolet-visible spectrometry (UV-vis), fluorescence spectrum and transmission electron micrographs (TEM). The results showed that the gamma-CD/FA-coated CdSe/ZnS QDs not only have good monodispersity and smaller size, but also have good optical performance, such as higher quantum yield (QY) and a long fluorescence lifetime. The cytotoxicity experiments showed that the gamma-CD/FA-coated CdSe/ZnS QDs have lower cytotoxicity and could more effectively enter cancer cells with FR over-expression. The QDs with 4-5 nm in diameter were relatively easy to enter the cell and to be removed through kidneys, so it is more suitable for biomedical applications for bioprobes and bioimaging.
Cadmium Compounds ; chemical synthesis ; chemistry ; metabolism ; toxicity ; Cell Survival ; drug effects ; Folate Receptor 1 ; chemistry ; Folic Acid ; chemistry ; HeLa Cells ; Hep G2 Cells ; Humans ; Magnetic Resonance Spectroscopy ; Microscopy, Electron, Transmission ; Molecular Imaging ; methods ; Quantum Dots ; chemistry ; metabolism ; toxicity ; Selenium Compounds ; chemical synthesis ; chemistry ; metabolism ; toxicity ; Spectrophotometry, Ultraviolet ; Spectroscopy, Fourier Transform Infrared ; Sulfides ; chemical synthesis ; chemistry ; metabolism ; toxicity ; Zinc Compounds ; chemical synthesis ; chemistry ; metabolism ; toxicity ; gamma-Cyclodextrins ; chemistry

This study describes the neuropathologic features of normal canine brain ablated with non-thermal irreversible electroporation (N-TIRE). The parietal cerebral cortices of four dogs were treated with N-TIRE using a dose-escalation protocol with an additional dog receiving sham treatment. Animals were allowed to recover following N-TIRE ablation and the effects of treatment were monitored with clinical and magnetic resonance imaging examinations. Brains were subjected to histopathologic and ultrastructural assessment along with Bcl-2, caspase-3, and caspase-9 immunohistochemical staining following sacrifice 72 h post-treatment. Adverse clinical effects of N-TIRE were only observed in the dog treated at the upper energy tier. MRI and neuropathologic examinations indicated that N-TIRE ablation resulted in focal regions of severe cytoarchitectural and blood-brain-barrier disruption. Lesion size correlated to the intensity of the applied electrical field. N-TIRE-induced lesions were characterized by parenchymal necrosis and hemorrhage; however, large blood vessels were preserved. A transition zone containing parenchymal edema, perivascular inflammatory cuffs, and reactive gliosis was interspersed between the necrotic focus and normal neuropil. Apoptotic labeling indices were not different between the N-TIRE-treated and control brains. This study identified N-TIRE pulse parameters that can be used to safely create circumscribed foci of brain necrosis while selectively preserving major vascular structures.
Animals ; Brain/metabolism/*pathology/surgery/ultrastructure ; Caspase 3/metabolism ; Caspase 9/metabolism ; Dogs ; Electroporation/veterinary ; Magnetic Resonance Imaging/methods ; Microscopy, Electron, Transmission ; Necrosis/metabolism/pathology ; Neurosurgical Procedures/*adverse effects

Opisthorchis viverrini infection causes inflammation and liver injury leading to periductal fibrosis. Little is known about the pathological alterations in bile canaliculi in opisthorchiasis. This study aimed to investigate bile canalicular alterations in O. viverrini-infected hamsters and to examine the chemopreventive effects of curcumin on such changes. Hamsters were infected with O. viverrini and one group of animals was fed with 1% dietary curcumin supplement. Animals were examined during the acute infection phase, days 21 and 30 post-infection (PI) and chronic infection phase (day 90 PI). Scanning electron microscopy revealed that in the infected group fed with a normal diet, bile canaliculi became slightly tortuous by 30 day PI and more tortuous at day 90 PI. Transmission electron microscopy showed a reduction in microvilli density of canaliculi starting at day 30 PI, with a marked loss of microvilli at day 90 PI. These ultrastructral changes were slightly seen at day 21 PI, which was similar to that found in infected animals fed with 1% curcumin-supplemented diet. Notably, curcumin treatment prevented the reduction of microvilli density, reduced the dilation of bile canaliculi, and decreased the tortuosity of the bile canaliculi relative to non-infected animals on a normal diet at days 30 and 90 PI. These results suggest that curcumin reduces alteration of bile canaliculi and may be a promising agent to prevent the onset of bile duct abnormalities induced by O. viverrini infection.
Animals ; Anthelmintics/*administration & dosage ; Bile Canaliculi/*pathology/ultrastructure ; Chemoprevention/methods ; Cricetinae ; Curcumin/*administration & dosage ; Disease Models, Animal ; Electrons ; Liver/pathology/ultrastructure ; Male ; Mesocricetus ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Opisthorchiasis/parasitology/*pathology/*prevention & control ; Opisthorchis/*growth & development

BACKGROUNDMagnetic resonance (MR) molecular imaging can detect abnormalities associated with disease at the level of cell and molecule. The epidermal growth factor receptor (EGFR) plays an important role in the development of lung cancer. This study aimed to explore new MR molecular imaging targeting of the EGFR on lung cancer cells.

METHODSWe attached ultra-small superparamagnetic iron oxide (USPIO) particles to cetuximab (C225) anti-human IgG using the carbodiimide method. We made the molecular MR contrast agents C225-USPIO and IgG-USPIO, the latter as a control reagent, and determined concentrations according to the Fe content. Lung cancer A549 cells were cultured and immunocytochemistry (SP) was used to detect the expression of EGFR on cells. We detected the binding rate of C225-USPIO to A549 cells with immunofluorescence staining and flow cytometry. We cultured A549 cells with C225-USPIO at a Fe concentration of 50 µg/ml and assayed the binding of C225-USPIO after 1 hour with Prussian blue staining and transmission electron microscopy (TEM). We determined the effects on imaging of the contrast agent targeted to cells using a 4.7T MRI. We did scanning on the cells labeled with C225-USPIO, IgG-USPIO, and distilled water, respectively. The scanning sequences included axial T1WI, T2WI.

RESULTSImmunocytochemical detection of lung cancer A549 cells found them positive for EGFR expression. Immunofluorescence staining and flow cytometry after cultivation with different concentrations of C225-USPIO showed the binding rate higher than the control. Prussian blue staining and transmission electron microscopy revealed that in the C225-USPIO contrast agent group of cells the particle content of Fe in cytoplasmic vesicles or on surface was more than that in the control group. The 4.7T MR imaging (MRI) scan revealed the T2WI signal in the C225-USPIO group of cells decreased significantly more than in unlabeled cells, but there was no significant difference between the time gradients.

CONCLUSIONSWe successfully constructed the molecular imaging agent C225-USPIO targeting the EGFR of A549 lung cancer cells. The imaging agent showed good targeting effect and specificity, and reduced MRI T2 value significantly, thus such molecular contrast agents could provide a new way to measure EGFR levels.

Antibodies, Monoclonal ; chemistry ; Antibodies, Monoclonal, Humanized ; Cell Line, Tumor ; Cetuximab ; Contrast Media ; chemistry ; Dextrans ; chemistry ; Ferric Compounds ; chemistry ; Humans ; Immunohistochemistry ; Lung Neoplasms ; metabolism ; Magnetic Resonance Imaging ; methods ; Magnetite Nanoparticles ; chemistry ; Microscopy, Electron, Transmission ; Receptor, Epidermal Growth Factor ; metabolism

This article reports that nano-silica solid dispersion technology was used to raise genistein efficiency through increasing the enzymatic hydrolysis rate. Firstly, genistin-nano-silica solid dispersion was prepared by solvent method. And differential scanning calorimetry (DSC) and transmission electron microscopy (TEM) were used to verify the formation of solid dispersion, then enzymatic hydrolysis of solid dispersion was done by snailase to get genistein. With the conversion of genistein as criteria, single factor experiments were used to study the different factors affecting enzymatic hydrolysis of genistin and its solid dispersion. And then, response surface method was used to optimize of nano-silica solid dispersion technology assistant enzymatic hydrolysis. The optimum condition to get genistein through enzymatic hydrolysis of genistin-nano-silica solid dispersion was pH 7.1, temperature 52.2 degrees C, enzyme concentration 5.0 mg x mL(-1) and reaction time 7 h. Under this condition, the conversion of genistein was (93.47 +/- 2.40)%. Comparing with that without forming the genistin-nano-silica solid dispersion, the conversion increased 2.62 fold. At the same time, the product of hydrolysis was purified to get pure genistein. The method of enzymatic hydrolysis of genistin-nano-silica solid dispersion by snailase to obtain genistein is simple, efficiency and suitable for the modern scale production.
Animals ; Calorimetry, Differential Scanning ; Genistein ; chemistry ; Hydrogen-Ion Concentration ; Hydrolysis ; Isoflavones ; chemistry ; Microscopy, Electron, Transmission ; Nanoparticles ; Phytoestrogens ; chemistry ; Silicon Dioxide ; chemistry ; Snails ; enzymology ; Solubility ; Technology, Pharmaceutical ; methods

This study is to report the preparation of complexes of Ad5 and anionic liposomes (AL-Ad5), the amplification of adenoviruses with enhanced green fluorescent protein (eGFP) reporter gene performed by HEK 293 cells, the adenoviral vectors purified by cesium chloride gradient centrifugation, and the titer of adenovirus determined by cytopathic effect (CPE) method, hexon capsid immunoassay and quantitative-PCR (Q-PCR), separately. The prescription and experiment conditions were optimized by central composite design (CCD). The complexes of Ad5 and AL-Ad5 were formulated by the calcium-induced phase change method. The morpholopy, particle size and zeta potential were detected by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. Additionally, the bicolourable fluoresce-labeled complexes (F(labeled)-AL-Ad5) were prepared and their intracellular location in MDCK cells was detected by confocal laser scanning microscopy (CLSM). The results indicate that the complexes of AL-Ad5 exhibited a uniform distribution with a particle size of 211 +/- 10 nm and a zeta potential of -41.2 +/- 2.2 mV. The result of CLSM demonstrates that the intracellular location of red fluoresce-labeled adenovirus was consistent with that of green fluoresce-labeled liposomes suggesting that the naked adenovirus was well encapsulated by the anionic liposomes in complexes of AL-Ad5.
Adenoviridae ; genetics ; ultrastructure ; Animals ; Anions ; Cytopathogenic Effect, Viral ; Dogs ; Drug Compounding ; methods ; Genetic Vectors ; Green Fluorescent Proteins ; chemistry ; HEK293 Cells ; Humans ; Liposomes ; chemistry ; pharmacokinetics ; ultrastructure ; Madin Darby Canine Kidney Cells ; Microscopy, Confocal ; Microscopy, Electron, Transmission ; Particle Size ; Polymerase Chain Reaction ; methods ; Recombinant Fusion Proteins ; ultrastructure