Study on a New Ultraviolet Sterilizer to the Surface Disinfection of the Ultrasound Probe.

We studied the disinfection effect of a new ultraviolet (UV) sterilizer and its utilization on ultrasound probe surfaces. Carrier quantitative germicidal tests, simulated on-the-spot trials, and organic substance influence tests were used to carry out experimental observation. Artificially infected probes were disinfected using the sterilizer or a germicidal lamp for comparison. The total number and types of bacteria were determined and identified. Our results demonstrated the sterilizer had the best disinfection effect among three different disinfection methods in hospital. The sterilizer has been used in a hospital setting for 2 years with no notable damage to the ultrasound probe instrument. It has the advantages of fast disinfection, high disinfection effect, and good compatibility with the ultrasound instrument, worthy of being a promoted application in medical institutions.

Hepatoid adenocarcinoma of the stomach: A case report and literature review.

Hepatoid adenocarcinoma (HAC) is a rare form of gastric cancer that has unique clinicopathological features and an extremely poor prognosis. The present case report describes a patient who was referred to the No. 461 Hospital of PLA (Changchun, China) due to nausea and occasional vomiting of acid/water. The patient was diagnosed with gastric signet-ring cell carcinoma and surgery was recommended. A total gastrectomy was performed on the operable lesion. Histopathological analysis revealed that the tumors exhibited two pathological changes: HAC and signet-ring cell carcinoma differentiation. Furthermore, the tumor cells were immunohistochemically positive for α-fetoprotein, cytokeratin low/high molecular weight, Cam5.2, cytokeratin 7, p53, epithelial membrane antigen and carcinoembryonic antigen. Previous studies and our experience have suggested that HAC is an aggressive type of adenocarcinoma; however, radical surgery and chemotherapy may positively impact clinical outcomes.

Responses of Phanerochaete chrysosporium to toxic pollutants: physiological flux, oxidative stress, and detoxification.

The white-rot fungus Phanerochaete chrysosporium has been widely used for the treatment of waste streams containing heavy metals and toxic organic pollutants. The development of fungal-based treatment technologies requires detailed knowledge of the relationship between bulk water quality and the physiological responses of fungi. A noninvasive microtest technique was used to quantify real-time changes in proton, oxygen, and cadmium ion fluxes following the exposure of P. chrysosporium to environmental toxic (2,4-dichlorophenol and cadmium). Significant changes in H(+) and O(2) flux occurred after exposure to 10 mg/L 2,4-dichlorophenol and 0.1 mM cadmium. Cd(2+) flux decreased with time. Reactive oxygen species formation and antioxidant levels increased after cadmium treatment. Superoxide dismutase activity correlated well with malondialdehyde levels (r(2) = 0.964) at low cadmium concentrations. However, this correlation diminished and malondialdehyde levels significantly increased at the highest cadmium concentration tested. Real-time microscale signatures of H(+), O(2), and Cd(2+) fluxes coupled with oxidative stress analysis can improve our understanding of the physiological responses of P. chrysosporium to toxic pollutants and provide useful information for the development of fungal-based technologies to improve the treatment of wastes cocontaminated with heavy metals and organic pollutants.

[Extracellular polymeric substances (EPS) of white-rot fungus and their effects on Pb2+ adsorption by biomass].

The extracellular polymeric substances (EPS) of P. chrysosporium and their effects on Pb2+ biosorption were studied. The product, composition of EPS and the effects on Pb2+ biosorption capacity were investigated in lab via flask experiments. The surface changes of mycelium before and after EPS extraction, before and after Pb2+ adsorption were researched by environment scanning electron microscope with energy-dispersive X-ray analysis (ESEM-EDX). Results showed that at 113 h, the maximum yield of EPS was 125.5 mg/L, which contained 46.6% - 54.3% of sugar and 31.2% - 35.1% of protein. The results of control test after EPS extraction displayed a decrease of biosorption capacity of Pb2+ among 2.12 mg/g (113 h) - 7.73 mg/g (41 h). The results of environment scanning electron microscope (ESEM) showed that the EPS extraction affected the cell wall of white-rot fungus and the Pb-contained globular particle after Pb2+ uptake, which was very useful for further study on heavy metal biosorption mechanism.

Coarsening of extracellularly biosynthesized cadmium crystal particles induced by thioacetamide in solution.

A novel coarsening route for extracellularly biosynthesized cadmium nanocrystals was investigated for the first time. In this process, the white rot fungus Coriolus versicolor was employed to take up cadmium ions and synthesize extracellular cadmium crystal particles. The coarsening of the particles was induced by thioacetamide under certain conditions. Scanning electron microscopy showed that the formed cadmium crystal particles were coarsened from about 100nm to 2-3µm. The corresponding energy-dispersive X-ray spectra confirmed the presence of proteins in the particles. The maximum removal efficiency of Cd(II) increased from 17% to 87%, and the corresponding sorption capacity of biomass increased from 4 to 24mgg(-1) with the completion of the coarsening process. The properties of the coarsened particles were also examined using X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD analysis of fungal mycelial pellets embedded with the coarsened particles confirmed the formation of cubic crystalline cadmium sulfide particles. The TEM results suggest that the coarsened particles were composed of clusters of several smaller particles. The changes in the functional groups on the biomass surface were studied through Fourier transform infrared spectroscopy. Based on the results above, a possible mechanism for the formation and coarsening of cadmium crystal particle is also discussed.

Surface-modified Phanerochaete chrysosporium as a biosorbent for Cr(VI)-contaminated wastewater.

To improve the removal efficiency of heavy metals from wastewater, the surface of a fungal biomass was modified to obtain a high-capacity biosorbent for Cr(VI) in wastewater. The effects of pH, initial concentration, and sorption time on Cr(VI) removal by polyethylenimine (PEI)-modified Phanerochaete chrysosporium were investigated. The biomass adsorption capacity was significantly dependent on the pH of the solution, and the optimum pH was approximately 3.0. The maximum removal for Cr(VI) was 344.8 mg/g as determined with the Langmuir adsorption isotherm. Pseudo-first-order Lagergren model is better than pseudo-second-order Lagergren model when simulating the kinetic experiment results. Furthermore, an amount of Cr(VI) was reduced to Cr(III), indicating that some reactions occurred on the surface of the biomass leading to the reduction of Cr(VI). The point of zero potential for the modified biomass increased from an initial pH of 3.0 to a much higher value of 10.8, indicating that the PEI-modified biomass is better than the pristine biomass for adsorption of anionic adsorbates. Results showed that the PEI-modified biosorbent presented high efficiency in treating Cr(VI)-contaminated wastewater.

Application of a by-product of Lentinus edodes to the bioremediation of chromate contaminated water.

The agricultural by-product of Lentinus edodes was used as a novel biosorbent for bioremediation of chromate contaminated waste water in the simulated experimental conditions. The contact time, particle size, biosorbent dosage and optimum pH range were investigated to optimize the sorption condition. The biosorption by the biomass was strongly affected by pH. At pH 1.0-2.5, all hexavalent chromium was diminished, either removed by the biosorbent or reduced to less toxic trivalent chromium even in very high concentration of 1000 mg/L. The adsorbed hexavalent chromium and reduced trivalent chromium were both linearly dependent on the initial chromium concentration. Most uptake of Cr occurred at pH around 4. The maximum uptake of chromium was 21.5 mg/g when simulated with Langmuir model, which showed the potential biosorption capacity of this biomaterial. The change of oxidation-reduction potential (ORP) during biosorption process revealed strong reduction ability of this biosorbent. Comparing analysis from Fourier transform infrared spectrums indicated that nitrogen oxide and carboxyl groups were increased after biosorption. The energy-dispersive X-ray microanalyzer revealed the mechanism of cation exchange during biosorption.

A novel biosorbent: characterization of the spent mushroom compost and its application for removal of heavy metals.

The spent mushroom compost of Lentinus edodes was used as a biosorbent for adsorbing cadmium, lead and chromium from solutions under batch conditions for the first time. Titration of the biomass revealed that it contained at least three types of functional groups. The Fourier transform infrared spectrometry showed that the carboxyl, phosphoryl, phenolic groups were the main groups. The simulated values of pKH and molar quantity were 5.00 and 0.44 mmol/g, 7.32 and 1.38 mmol/g, 10.45 and 1.44 mmol/g, respectively. The biosorption ability increased with pH in acid condition. When 10 mg/L biomass dosage was added in, there was no significant increment of metal uptake. The maximum uptake estimated with the Langmiur isotherm model were 833.33 mg/g for Cd(II), 1000.00 mg/g for Pb(II) and 44.44 mg/g for Cr(III), respectively. All the results showed that vast potential sorption capacity was existed in the biomass for adsorbing these three kinds of metals studied.