Combination of deep eutectic solvent and functionalized metal-organic frameworks as a green process for the production of 5-hydroxymethylfurfural and furfural from sugars

Biomass is an abundant and sustainable resource that can be converted into energy and chemicals. Therefore, the development of efficient methods for the conversion of biomass into platform intermediates is crucial. In this study, the one-pot conversion of sugars into 5-hydroxymethylfurfural (HMF) and furfural was achieved using the metal-organic framework combined with metal ions [MIL-101(Cr)] as a high-activity catalyst, and a deep eutectic solvent (choline chloride and lactic acid) as a green solvent. The optimal temperature, time, amount of catalyst used, and amount of deep eutectic solvent used were all determined. The highest HMF yield of 49.74% and furfural yield of 55.90% were obtained. The recyclability of the catalysts and deep eutectic solvent was also investigated. After three reaction runs, the HMF yield was still nearly 30.00%. Finally, the MIL-101(Cr) catalytic system was selected to study the kinetic mechanism underlying the conversion of glucose into HMF.

Highly effective synthesis of 5-hydroxymethylfurfural from lignocellulosic biomass over a green and one-pot reaction in biphasic system

In this study, different types of lignocellulosic biomas were used as substrates for the conversion to 5-HMF via biphasic reaction system that is composed of a reaction phase (aqueous phase) and an extraction phase (organic phase) under the catalysis of various metal salts. Deep eutectic solvents (DESs), ionic liquid [BMIM]Cl, aqueous choline chloride, aqueous betaine hydrochloride, and ethylamine hydrochloride were used as the reaction phase in the combination of dimethyl sulfoxide (DMSO) as organic solvents. The highest yields of 5-HMF obtained from pineapple stems in reactions with DES were 40.98%, 37.26%, and 23.44% for ChCl:Lac, ChCl:OA, and EaCl:Lac, respectively. Moreover, the combination of dimethyl sulfoxide, betaine hydrochloride aqueous solution, and AlCl3·6H2O with the pineapple stem conversion system resulted in a maximum yield of 61.04% ± 0.55% of 5-HMF. This study also demonstrated that AlCl3·6H2O and betaine hydrochloride could be effectively reused four times, which indicates a green and effective process.

Valorization of Glucose-Derived Humin as a Low-Cost, Green, Reusable Adsorbent for Dye Removal, and Modeling the Process

Glucose can be isomerized into fructose and dehydrated into key platform biochemicals, following the "bio-refinery concept". However, this process generates black and intractable substances called humin, which possess a polymeric furanic-type structure. In this study, glucose-derived humin (GDH) was obtained by reacting D-glucose with an allylamine catalyst in a deep eutectic solvent medium, followed by a carbonization step. GDH was used as a low-cost, green, and reusable adsorbent for removing cationic methylene blue (MB) dye from water. The morphology of carbonized GDH differs from pristine GDH. The removal efficiencies of MB dye using pristine GDH and carbonized GDH were 52% and 97%, respectively. Temperature measurements indicated an exothermic process following pseudo-first-order kinetics, with adsorption behavior described by the Langmuir isotherm. The optimum parameters were predicted using the response surface methodology and found to be a reaction time of 600 min, an initial dye concentration of 50 ppm, and a GDH weight of 0.11 g with 98.7% desirability. The MB dye removal rate optimized through this model was 96.85%, which was in good agreement with the experimentally obtained value (92.49%). After 10 cycles, the MB removal rate remained above 80%, showcasing the potential for GDH reuse and cost-effective wastewater treatment.

Microwave-assisted deep eutectic solvents/dimethyl sulfoxide system for efficient valorization of sugar bagasse waste into platform chemicals: A biorefinery approach for circular bioeconomy

The exploitation of lignocellulosic biomass (LB) such as sugar bagasse waste in biorefineries is the most cost-effective and favourable sustainable approach to producing essential platform chemicals, materials, and energy environmentally benignly. Herein, a microwave-mediated deep eutectic solvents (DESs)/dimethyl sulfoxide (DMSO) system for efficiently processing LB waste into platform chemicals was proposed thereof. Under optimized appropriate diverse parameters such as solvent varieties, catalyst dosage, DMSO addition, reaction time and temperature, the proposed catalytic system (i.e., microwave mediated DESs/DMSO system) has demonstrated significant yields of 5-hydroxymethylfurfural (5-HMF), furfural (FF) and levulinic acid (LevA) of 31.29 %, 28.38 % and 35.65 %, respectively. These favourable results were obtained at the reaction temperature of 140 °C for 40 min. The anticipated catalytic system's activation energy (Ea) was found to be 29.11 kJ/mol. Hence, a practical, inexpensive and sustainable process with the potential of high-value platform chemicals, explicitly for a sustainable strategy in a circular bioeconomy was proposed.

Synthesis of 5-hydroxymethylfurfural from glucose, fructose, cellulose and agricultural wastes over sulfur-doped peanut shell catalysts in ionic liquid

In this study, waste peanut shells were sulfur-impregnated and used as acid catalysts in the presence of an ionic liquid for the conversion of fructose, glucose, and cellulose into 5-hydroxymethylfurfural, a useful chemical intermediate for biofuel production. Effects of sulfur-doping duration (1 h and 5 h), solvent type and proportion, reaction temperature (130 °C, 140 °C, and 150 °C), time (30-240 min), catalyst-to-substrate ratio (1-2.5 m/m), and agricultural residue (peanut shell, Canada wheat straw, water hyacinth, stalk, and reed) on HMF yields were investigated. Monophasic and biphasic ionic liquids such as [amim]Cl, [bmim]HSO₄, and [emim]Cl were employed in combination with choline chloride and dimethyl sulfoxide to improve HMF yields. Results show that peanut shells subjected to prolonged sulfur impregnation produced higher HMF yields. At 130 °C and 2 h, HMF yields from fructose and glucose reached 94.6% and 55.1%, respectively. Higher reaction temperatures improved HMF yields and accelerated conversion rates for the sugar substrates. Moreover, HMF production from waste biomass namely, peanut shells, peanut stalk, Canadian wheat straw, reed, and water hyacinth were examined in separate one-pot catalytic reactions. Overall, the study showed the effectiveness of sulfur-doped peanut shells as solid acid catalysts for the synthesis of HMF from various sources and the results may be used in designing large-scale production of furanic biofuel precursors from agricultural wastes.

Removal of Isopropanol by synergistic non-thermal plasma and photocatalyst

The dielectric barrier discharge (DBD) of non-thermal plasmas was combined with a self-made photocatalyst to remove isopropanol (IPA). Synthesis conditions for the novel photocatalyst, including calcination temperature and copper loading, were varied before photocatalysis to obtain at the optimal reaction efficiency. The effects of initial IPA concentration, oxygen content, and catalyst dosage were also observed. Finally, catalyst reusability was analyzed. X-ray photoelectron spectroscopy fitting revealed Ti, Cu, C, and O peaks in the synthesized catalyst. After a 60-min reaction with 100% oxygen as the carrying gas, nearly 100% of the IPA was converted. Overall, the optimal IPA conversion efficiency and acetone and carbon dioxide selectivity were achieved when the photocatalyst was synthesized at a calcination temperature of 550 °C and copper loading of 1.8%, along with a 100% oxygen carrying gas and a 3-mm discharge gap.

Influence of Chymosin on Physicochemical and Hydrolysis Characteristics of Casein Micelles and Individual Caseins

The effects of chymosin on the physicochemical and hydrolysis characteristics of casein micelles and individual caseins were investigated. Adding 0.03 units of chymosin/mL led to the casein micelles in skim milk coagulating after a 3 h incubation period at 30 °C. SDS–PAGE investigation showed that β-CN, κ-CN, α_s-CN, and a portion of β-lactoglobulin (β-LG) in the milk supernatant fraction (MSF) were precipitated into the milk pellet fraction (MPF). The mean particle size of the MSF with chymosin decreased from 254.4 nm to 179.2 nm after a 3 h incubation period. Mass spectrometry and SDS–PAGE analysis suggested that chymosin hydrolyzed individual β-CN, κ-CN, and α_s-CN, but not β-LG. Chymosin hydrolysis led to a decrease in the molecular weights of the hydrolyzed β-CN, κ-CN, and α_s-CN. Particle size analysis indicated that there was no difference in the particle size distribution of hydrolyzed β-CN and α_s-CN. Moreover, our outcomes demonstrated that the hydrolysis of κ-CN by chymosin occurs before that of β-CN and α_s-CN.

Interplays of enzyme, substrate, and surfactant on hydrolysis of native lignocellulosic biomass

Tracking enzyme, substrate, and surfactant interactions to reach maximum reducing sugar production during enzymatic hydrolysis of plant biomass may provide a better understanding of factors that limit the lignocellulosic material degradation in native rice straw. In this study, enzymes (Cellic Ctec2 cellulase and Cellic Htec2 xylanase) and Triton X-100 (surfactant) were used as biocatalysts for cellulose and xylan degradation and as a lignin blocking agent, respectively. The response surface model (R² = 0.99 and R²-adj = 0.97) indicated that Cellic Ctec2 cellulase (p < 0.0001) had significant impacts on reducing sugar production, whereas Cellic Htec2 xylanase and Triton X-100 had insignificant impacts on sugar yield. Although FTIR analysis suggested binding of Triton X-100 to lignin surfaces, the morphological observation by SEM revealed similar surface features (i.e., smooth surfaces with some pores) of rice straw irrespective of Triton X-100. The reducing sugar yields from substrate hydrolysis with or without the surfactant were comparable, suggesting similar exposure of polysaccharides accessible to the enzymes. The model analysis and chemical and structural evidence suggest that there would be no positive effects on enzymatic hydrolysis by blocking lignins with Triton X-100 if high lignin coverage exists in the substrate due to the limited availability of hydrolyzable polysaccharides.

Conversion of rice husk into fermentable sugar and silica using acid-catalyzed ionic liquid pretreatment

Rice husk is a bulky byproduct with a high silica content from rice milling. In this study, the application of an acid-catalyzed ionic liquid (IL) pretreatment was studied for processing rice husks with a rugged structure. The pretreatment conditions were 130°C for 30 min with 1.2 wt% HCl. The results of enzymatic hydrolysis demonstrated that cellulose conversion of HCl-BMIMCl-treated at 48 h was increased by 660.05%, 538.81%, and 376.55% compared with the untreated, HCl-treated, and BMIMCl-treated rice husks, respectively. Composition analysis demonstrated that most of the hemicellulose was removed in the acid-IL combined treatment. Moreover, scanning electron microscopy, X-ray diffraction (XRD), and Fourier transform infrared analyses indicated that the crystalline structure and outer silica layer of the rice husks were efficiently broken up. The results revealed that the HCl-catalyzed dissolution is highly favorable for the industrial application of rick husks in the production of fermentable sugar and high-purity silica.

Recycle of synthetic calcium fluoride and waste sulfuric acid to produce electronic grade hydrofluoric acid

An innovative method for utilizing synthetic calcium fluoride (CaF₂), recovered from fluoride-containing semiconductor wastewater, and waste sulfuric acid (H₂SO₄) to produce hydrofluoric acid (HF) was investigated. The research was set to study the low-temperature production of HF via reaction of synthetic CaF₂ and waste H₂SO₄. The impact of four factors, including H₂SO₄ concentration, total volume (H₂SO₄ + H₂O)/CaF₂ ratio, drying temperature of synthetic CaF₂, and reaction carried out under different temperature, on HF productivity was investigated in this study. HF yield increased with increasing H₂SO₄ concentration and total volume/CaF₂ ratio under room temperature. Generally, reactions carried out under low-temperature (< 100 °C) had a positive impact on HF yield. The higher temperature led to an increase in absorbed-HF but a decrease in total-HF. The reaction of commercial CaF₂ and 70% H₂SO₄ had a higher absorbed-HF yield of 61.7% than synthetic CaF₂ and 70% waste H₂SO₄, which had a yield of 36%. This was due to the higher purity of the commercial CaF₂ and fewer interference ions in H₂SO₄. HF productivity was lowered by CaSO₄, which hindered the reaction of reactants and also the generation of fluorosulfuric acid.

Gas-phase isopropanol degradation by nonthermal plasma combined with Mn-Cu/-Al2O3

In this study, the dielectric barrier discharge (DBD) induced by nonthermal plasma (NTP) technology was used for isopropanol (IPA) degradation. IPA, intermediate, final product, and ozone concentrations were analyzed using GC-MS, carbon dioxide detector, and ozone detector. The experimental flow rate and concentration were fixed to 1 L/min and 1200 ppm ± 10%, respectively. Different reaction procedures were proposed for self-made metal catalyst combined with a plasma system (plasma alone and γ-Al₂O₃ combined with plasma, Cu (5 wt%)/γ-Al₂O₃ combined with plasma, Mn (3 wt%)-Cu (5 wt%)/γ-Al₂O₃ combined with plasma). In addition, the effect of the carrier gas oxygen content (0%, 20%, and 100%) on IPA conversion and intermediate and carbon dioxide selectivity was also investigated. The results revealed that the Mn (F)-Cu/γ-Al₂O₃ combined with plasma exhibited more efficient IPA conversion. In the 100% oxygen environment, the IPA conversion rate increased from 79.32 to 99.99%, and carbon dioxide selectivity increased from 3.82 to 50.23%. IPA was completely converted after 60 min of plasma treatment with the acetone selectivity, carbon dioxide selectivity, and tail ozone concentration of 26.71% ± 1.27%, 50.23% ± 0.56%, and 1761 ± 11 ppm, respectively. This study proved that the current single planar DBD configuration is an effective advanced treatment technology for the decomposition of VOCs.

Iron Modified Titanate Nanotube Arrays for Photoelectrochemical Removal of E. coli

This study used iron modified titanate nanotube arrays (Fe/TNAs) to remove E. coli in a photoelectrochemical system. The Fe/TNAs was synthesized by the anodization method and followed by the square wave voltammetry electrochemical deposition (SWVE) method with ferric nitrate as the precursor. Fe/TNAs were characterized by SEM, XRD, XPS, and UV-vis DRS to investigate the surface properties and light absorption. As a result, the iron nanoparticles (NPs) were successfully deposited on the tubular structure of the TNAs, which showed the best light utilization. Moreover, the photoelectrochemical (PEC) properties of the Fe/TNAs were measured by current-light response and electrochemical impedance spectroscopy. The photocurrent of the Fe/TNAs-0.5 (3.5 mA/cm2) was higher than TNAs (2.0 mA/cm2) and electron lifetime of Fe/TNAs-0.5 (433.3 ms) were also longer than TNAs (290.3 ms). Compared to the photolytic (P), photocatalytic (PC), and electrochemical (EC) method, Fe/TNAs PEC showed the best removal efficiency for methyl orange degradation. Furthermore, the Fe/TNAs PEC system also performed better removal efficiency than that of photolysis method in E. coli degradation experiments.

Construction of a structural enzyme adsorption/kinetics model to elucidate additives associated lignin-cellulase interactions in complex bioconversion system

Enzymatic hydrolysis is a rate-limiting process in lignocellulose biorefinery. The reaction involves complex enzyme-substrate and enzyme-lignin interactions in both liquid and solid phases, and has not been well characterized numerically. In this study, a kinetic model was developed to incorporate dynamic enzyme adsorption and product inhibition parameters into hydrolysis simulation. The enzyme adsorption coefficients obtained from Langmuir isotherm were fed dynamically into first-order kinetics for simulating the equilibrium enzyme adsorption in hydrolysis. A fractal and product inhibition kinetics was introduced and successfully applied to improve the simulation accuracy on adsorbed enzyme and glucose concentrations at different enzyme loadings, lignin contents, and in the presence of bovine serum albumin (BSA) and lysozyme. The model provided numerical proof quantifying the beneficial effects of both additives, which improved the hydrolysis rate by reducing the nonproductive adsorption of enzyme on lignin. The hydrolysis rate coefficient and fractal exponent both increased with increasing enzyme loadings, and lignin inhibition exhibited with increasing fractal exponent. Compared with BSA, the addition of lysozyme exhibited higher hydrolysis rates, which was reflected in the larger hydrolysis rate coefficients and smaller fractal exponents in the simulation. The model provides new insights to support process development, control, and optimization.

Degradation of trichloroethylene by photoelectrochemically activated persulfate

Chlorine-containing organic compounds were discharged informally as a result of untreated industrial wastewater, which caused groundwater pollution. In this study, titanium dioxide nanotube arrays (TNAs) were modified with copper oxide to photoelectrochemical (PEC) active persulfate to degrade trichloroethylene (TCE). The SEM results show copper nano-particles with a cubic shape were successfully deposited on the surface of TNAs. The results of UV-vis analysis indicate the absorption wavelengths red-shift to 550-600 nm for better light utilization. CuO/TNAs were dominated by the anatase phase after sintering at 450 °C with significant visible light response. The chemical contents for the surface of CuO/TNAs are 23.7, 53.4, 18.4 and 4.4% for C, O, Ti and Cu, respectively. The photocurrent of CuO/TNAs is 1.89 times higher than that of TNAs_{-93 cm^2-1hr} under 100 W Hg-lamp illuminations. This demonstrates the efficiency of light utilization of TNAs was improved by the modification with copper nanoparticles. The degradation rate of TCE in the anodic chamber is more effective than that in the cathodic chamber because of the synergistic effect of hydroxyl and sulfate radicals. The mechanism of TCE degradation via persulfate in the PEC system was proposed and discussed in detail.

Detecting phthalate esters in sludge particulates from wastewater treatment plants

This study proposed a method for analysis of 10 phthalate esters compounds from wastewater treatment plant sludges. The analytical efficiency of GC-MS for of target compounds was verified by a standard mixture of phthalate esters. The response factors related to the respective internal standards from a five-point calibration curve quantified the phthalate esters in individual compounds. Based on the literature compiled by environmental agencies, new generation phthalate compounds have been developed, such as di-iso-nonyl phthalate (DiNP), di-iso-decyl phthalate (DiDP), as alternative to conventional phthalates. The analytical results showed that the total PAEs concentration was in the range from 7.4 to 138.6 mg kg^-1 dw in these seven analyzed sludge samples. More, di-iso-nonyl phthalate (DiNP), di-iso-decyl phthalate (DiDP) and bis(2-ethylhexyl) phthalate (DEHP) contributed to over 99% of PAEs in the sludge. The correlation between total PAEs concentration in household and sewage flow treated at seven WWTPs and concentrations of DEHP, DiNP and DiDP was significant.

Effect of microwave-assisted ionic liquid/acidic ionic liquid pretreatment on the morphology, structure, and enhanced delignification of rice straw

In the present study, was investigated an environmentally friendly method for pretreating lignocellulosic rice straw (RS) by using 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) as an ionic liquid (IL) and 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO₄) as an acidic-IL (Acidic-IL) under microwave irradiation (microwave-[Bmim]Cl and microwave-[Bmim]HSO₄). The conversion of lignocellulosic biomass into simple sugars requires both efficient pretreatment and hydrolysis enzymes to produce biofuels and specialty chemicals. Therefore, the applied [Bmim]Cl, [Bmim]HSO₄, microwave-[Bmim]Cl, and microwave-[Bmim]HSO₄ to improve hydrolysis yields. Structural analyses of the pretreated solids were performed to understand the synergistic effects of [Bmim]Cl, and [Bmim]HSO₄ pretreatment under microwave irradiation (microwave-[Bmim]Cl and microwave-[Bmim]HSO₄) on the efficiencies of enzymatic hydrolyses. The results of a chemical composition analysis of untreated and all pretreated RS samples by using the difference pretreatment methods showed that significant lignin removal was achieved using microwave-[Bmim]Cl (57.02 ± 1.24%), followed by [Bmim]Cl only (41.01 ± 2.67%), microwave-[Bmim]HSO₄ (20.77 ± 1.79%), and [Bmim]HSO₄-only (16.88 ± 1.14%). The highest glucan yield and xylan conversion achieved through the enzymatic saccharification of microwave-[Bmim]Cl-regenerated cellulose was consistent with the observations obtained from a structural analysis, which indicated a more disrupted, amorphous structure, with lowered crystallinity index (CrI) and lateral order index (LOI) of cellulose polymers. Thus results demonstrated that the pretreatment of lignocellulosic biomass with [Bmim]Cl under microwave irradiation has potential as an alternative method for pretreating lignocellulosic materials.

Effects of atmospheric-plasma system on energy efficiency improvement and emissions reduction from a diesel engine

Efficient energy usage and energy saving is one of the nowadays necessity for all scientists of IC engine. This is because of the current environmental challenges that have tremendously increased concerning air pollution, particularly pollutant emissions from vehicles. Yet, industries and governments alike have disregarded this phenomenon which has been considerably contributing to climate change. It is against this background that, the research works carried out in this present study is predominantly focusing on improving energy efficiency and reducing emission levels from diesel engines. This can be achieved with the help of atmospheric-plasma system which can offer a noble solution to the above-mentioned challenges due to its potential to improve combustion efficiency which leads to energy efficiency, while reducing emission levels from diesel engines. In this study, the performance and emissions of a diesel generator supplemented with an atmospheric-plasma system was examined. The diesel engine was used to examine the effects of fuel composition, or brake specific fuel consumption, thermal efficiency and pollutant emissions at different plasma system voltages. To this end, we equally examined the effects of atmospheric-plasma system on energy efficiency improvement and emissions reduction from diesel engine as the main purpose of this study. We do so by testing the diesel-fueled engine generator under the atmospheric-plasma system. The tests were carried out at a constant state condition with the engine running at 2200 rpm with torque and power outputs of 10.4 Nm (75% of the max load) and 2.1 kW, separately, for the tested fuels and this was used to increase the output voltage of the plasma system during this study. The plasma system ionized the intake air and improved the formation of free radicals upon combustion. During this study, the output voltage of the plasma was set within the range of 0-7 kV. The experimental results have indicated that formaldehyde, acetaldehyde and acrolein account for more than 75% of total carbonyl compounds emissions. Simultaneously, it was also observed from the results that higher plasma system voltage reduces pollutants emissions levels. Hence, such reduction is predominantly evident for nitrogen oxides, particulate matters and carbon monoxide. However, the marginal improvements of engine performance and emissions reduction become insignificant when the plasma system voltage reaches 6 kV. On the other hand, increasing the amount of plasma system voltages in diesel engine continues to significantly reduce pollutant emissions.

Enhanced photoelectrochemical degradation of Ibuprofen and generation of hydrogen via BiOI-deposited TiO2 nanotube arrays

This study employed BiOI-deposited TiO₂ nanotube arrays (BiOI-TNTAs) electrode in a photoelectrochemical (PEC) system to oxidize Ibuprofen and generate hydrogen in the anodic and cathodic chamber, respectively. FESEM results revealed the diameter of TiO₂ nanotubes was 90-110nm. According to the XRD analysis, the BiOI-TNTAs were dominated by the anatase phase and tetragonal structure of BiOI. XPS results confirmed the coexistence of BiOI in the BiOI-TNTAs associated with Bi (33.76%) and I (8.81%). UV-vis absorption spectra illustrated BiOI-TNTAs exhibit strong absorptions in the visible light region. The PEC method showed the best degradation efficiency for Ibuprofen is a rate constant of 3.21×10^-2min^-1. The results of the Nyquist plot revealed the recombination of photogenerated electron-hole pairs was inhibited as the bias potential was applied. Furthermore, the Bode plot demonstrated the lifetime (τ_el) of photoexcited electrons of BiOI-TNTAs was 1.8 and 4.1 times longer than that of BiOI-Ti and TNTAs, respectively. In the cathodic chamber, the amount of hydrogen generation reached 219.94μM/cm² after 3h of reaction time.

Enhanced Enzymatic Hydrolysis of Rice Straw Pretreated by Oxidants Assisted with Photocatalysis Technology

This work evaluated the effectiveness of rice straw pretreatment using a TiO₂/UV system in the presence of oxidants. The effects of TiO₂ concentrations, pH and photocatalysis time were investigated. Inorganic oxidants including H₂O_2, K₂S₂O₈, and KIO₄ were added to further enhance the effect on enzymatic hydrolysis of rice straw. The TiO₂/UV/ H₂O₂ pretreatment showed a higher amount of released reducing sugar (8.88 ± 0.10 mg/mL, compared to 5.47 ± 0.03 mg/mL in untreated sample). Composition analyses of rice straw after the TiO₂/UV/H₂O₂ pretreatment showed partial lignin and hemicellulose removal. Moreover, structural features of untreated and pretreated rice straw were analyzed through FE-SEM, FT-IR, and XRD. This work suggests that H₂O₂ is an efficient addition for photocatalysis pretreatment of rice straw.

Thermogravimetric Analysis of Textile Dyeing Sludge (TDS) in N₂/CO₂/O₂ Atmospheres and its Combustion Model with Coal

  The combustion characteristics of textile dyeing sludge (TDS) in N2/O2, CO2/O2, and N2/CO2 atmospheres, and blends of TDS with coal were analyzed using TGA (thermogravimetric analysis). Results showed that the replacement of N2 by CO2 resulted in negative effects on the combustion and pyrolysis of TDS. Comparing N2/O2 and CO2/O2 atmospheres, combustion of TDS was easier in a N2/O2 atmosphere, but the residual mass after TDS pyrolysis in pure CO2 was less than that in N2 by approximately 4.51%. When the proportion of TDS was 30-50% in the blends of coal with TDS, a synergistic interaction clearly occurred, and it significantly promoted combustion. In considering different combustion parameters, the optimal proportion of TDS may be between 20-30%. The activation energy Ea value decreased from 155.6 kJ/mol to 53.35 kJ/mol with an increasing TDS proportion from 0% to 50%, and it rapidly decreased when the TDS proportion was below 20%.

Influence of catalysts on co-combustion of sewage sludge and water hyacinth blends as determined by TG-MS analysis

Effects of the three metal carbonates (K₂CO₃, Na₂CO₃, and MgCO₃) were quantified on catalytic co-combustion of the sewage sludge and water hyacinth (SW) blend using a thermogravimetric-mass spectrometric (TG-MS) analysis and kinetics modeling. The main dominating steps of the catalysts were the organic volatile matter release and combustion stage. Weighted mean values of activation energy (E_m) were estimated at 181.18KJ·mol^-1, 199.76KJ·mol^-1, 138.76KJ·mol^-1, and 177.88KJ·mol^-1 for SW, SW+5% K₂CO₃, SW+5% Na₂CO₃, and SW+5% MgCO₃, respectively. The lowest E_m occurred with SW+5% Na₂CO₃. Overall, catalyst effect on co-combustion appeared to be negligible as indicated by Gibbs free energy (ΔG). The normalized intensities of SW+MgCO₃ were strongest. The addition of Na₂CO₃ and MgCO₃ to SW increased flue gases emissions (CO₂, NO₂, SO₂, HCN, and NH₃) of SW, whereas the addition of K₂CO₃ to SW reduced flue gases emissions from the entire combustion process.

The effect of surfactant-assisted ultrasound-ionic liquid pretreatment on the structure and fermentable sugar production of a water hyacinth

This study investigated the possibility of enhancing the disruption of water hyacinth (WH) in an ultrasound-ionic liquid (US-IL) pretreatment assisted by sodium dodecyl sulfate (SDS). 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) was used to dissolve the WH. The optimum concentration of SDS for the highest production of reducing sugar was also determined. Compared to the US-IL pretreatment, the production of reducing sugars, cellulose conversion and delignification were increased by 72.23%, 58.74% and 21.01%, respectively, upon addition of 0.5% SDS. Moreover, the enhancement of SDS in the US-IL pretreatment was confirmed by the analysis of structural features, which demonstrated that the SDS increased the removal of lignin and decreased the cellulose crystallinity.

Spent mushroom substrate biochar as a potential amendment in pig manure and rice straw composting processes

Spent mushroom substrate (SMS) is a bulky waste byproduct of commercial mushroom production, which can cause serious environmental problems and, therefore, poses a significant barrier to future expansion of the mushroom industry. In the present study, we explored the use of SMS as a biochar to improve the quality of bio-fertilizer. Specifically, we performed a series of experiments using composting reactors to investigate the effects of SMS biochar on the physio-chemical properties of bio-fertilizer. Biochar was derived from dry SMS pyrolysed at 500°C and mixed with pig manure and rice straw. Results from this study demonstrate that the addition of biochar significantly reduced electrical conductivity and loss of organic matter in compost material. Nutrient analysis revealed that the SMS-derived biochar is rich in fertilizer nutrients such as P, K, Na, and N. All of these findings suggest that SMS biochar could be an excellent medium for compost.

Impact of surfactant type for ionic liquid pretreatment on enhancing delignification of rice straw

This work describes an environmentally friendly method for pretreating rice straw by using 1-Allyl-3-methylimidazolium chloride ([AMIM]Cl) as an ionic liquid (IL) assisted by surfactants. The impacts of surfactant type (including nonionic-, anionic-, cationic- and bio-surfactant) on the ionic liquid pretreatment were investigated. The bio-surfactant+IL-pretreated rice straw showed significant lignin removal (26.14%) and exhibited higher cellulose conversion (36.21%) than the untreated (16.16%) rice straw. The cellulose conversion of the rice straw pretreated with bio-surfactant+IL was the highest and the lowest was observed for pretreated with cationic-surfactant+IL. Untreated and pretreated rice straw was thoroughly characterized through SEM and AFM. In conclusion, the results provided an effective and environmental method for pretreating lignocellulosic substrates by using green solvent (ionic liquid) and biodegradable bio-surfactant.

Investigation of co-combustion characteristics of sewage sludge and coffee grounds mixtures using thermogravimetric analysis coupled to artificial neural networks modeling

Artificial neural network (ANN) modeling was applied to thermal data obtained by non-isothermal thermogravimetric analysis (TGA) from room temperature to 1000°C at three different heating rates in air to predict the TG curves of sewage sludge (SS) and coffee grounds (CG) mixtures. A good agreement between experimental and predicted data verified the accuracy of the ANN approach. The results of co-combustion showed that there were interactions between SS and CG, and the impacts were mostly positive. With the addition of CG, the mass loss rate and the reactivity of SS were increased while charring was reduced. Measured activation energies (E_a) determined by the Kissinger-Akahira-Sunose (KAS) and Ozawa-Flynn-Wall (OFW) methods deviated by <5%. The average value of E_a (166.8kJ/mol by KAS and 168.8kJ/mol by OFW, respectively) was the lowest when the fraction of CG in the mixture was 40%.

Photoelectrochemical oxidation of ibuprofen via Cu2O-doped TiO2 nanotube arrays

A p-n junction based Cu2O-doped TiO2 nanotube arrays (Cu2O-TNAs) were synthesized and used as a working anode in a photoelectrochemical (PEC) system. The results revealed that the Cu2O-TNAs were dominated by the anatase phase and responded significantly to visible light. XPS analyses indicated that with an amount of 24.79% Cu doping into the structure, the band gap of Cu2O-TNAs was greatly reduced. SEM images revealed that the supported TiO2 nanotubes had diameters of approximately 80nm and lengths of about 2.63μm. Upon doping with Cu2O, the TiO2 nanotubes maintained their structural integrity, exhibiting no significant morphological change, favoring PEC applications. Under illumination, the photocurrent from Cu2O/TNAs was 2.4 times larger than that from TNAs, implying that doping with Cu2O significantly improved electron mobility by reducing the rate of recombination of electron-hole pairs. The EIS and Bode plot revealed that the estimated electron lifetimes, τel, of TNAs and Cu2O/TNAs were 6.91 and 26.26ms, respectively. The efficiencies of degradation of Ibuprofen by photoelectrochemical, photocatalytic (PC), electrochemical (EC) and photolytic (P) methods were measured.

Thermodynamics and kinetics parameters of co-combustion between sewage sludge and water hyacinth in CO2/O2 atmosphere as biomass to solid biofuel

Thermodynamics and kinetics of sewage sludge (SS) and water hyacinth (WH) co-combustion as a blend fuel (SW) for bioenergy production were studied through thermogravimetric analysis. In CO2/O2 atmosphere, the combustion performance of SS added with 10-40wt.% WH was improved 1-1.97 times as revealed by the comprehensive combustion characteristic index (CCI). The conversion of SW in different atmospheres was identified and their thermodynamic parameters (ΔH,ΔS,ΔG) were obtained. As the oxygen concentration increased from 20% to 70%, the ignition temperature of SW decreased from 243.1°C to 240.3°C, and the maximum weight loss rate and CCI increased from 5.70%·min(-1) to 7.26%·min(-1) and from 4.913%(2)·K(-3)·min(-2) to 6.327%(2)·K(-3)·min(-2), respectively, which corresponded to the variation in ΔS and ΔG. The lowest activation energy (Ea) of SW was obtained in CO2/O2=7/3 atmosphere.

Synergistic effects of surfactant-assisted ionic liquid pretreatment rice straw

The aim of this work was to study an environmentally friendly method for pretreating rice straw by using 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) as an ionic liquid (IL) assisted by surfactants. Different temperatures, reaction times, and surfactant concentrations were studied. Compared with [BMIM]Cl only pretreatment, the addition of 1% sodium dodecyl sulfate (SDS) and 1% cetyl trimethyl ammonium bromide (CTAB) increased lignin removal to 49.48% and 34.76%, respectively. Untreated and pretreated rice straw was thoroughly characterized through FTIR, XRD, and FE-SEM. Cellulose crystallinity and surface morphology of the rice straw were substantially altered after surfactant-assisted IL pretreatment. In conclusion, surfactant-assisted IL pretreatment is an effective method for producing fermentable sugars from lignocellulosic substrates.

Cu2O loaded titanate nanotube arrays for simultaneously photoelectrochemical ibuprofen oxidation and hydrogen generation

A p-n junction Cu2O doped TiO2 nanotube arrays (Cu2O/TNAs) were synthesized by square wave voltammetry electrochemical (SWVE) deposition method and employed as the working anode. The crystalline, optical properties, surface morphology, and structure of the Cu2O/TNAs were characterized by XRD, UV-vis absorbance edges, SEM, and XPS. Results showed that the Cu2O/TNAs were dominated by anatase phase after sintering at 450 °C with significant visible light response. XPS finding confirmed XRD results that the copper element in Cu2O/TNAs was Cu (I) instead of Cu (II). SEM images illustrated the diameter and the length of supported TiO2 nanotubes was approximately 100 nm and 2.75-4.34 μm, respectively. After Cu2O doping, the nano-tubular structure of TiO2 nanotube kept its integrity with no significant morphological change, which was beneficial for PEC applications. The photocurrent of Cu2O/TNAs was 1.45 times larger than that of TNAs, implying that Cu2O doping significantly enhanced electron mobility by reducing the recombination of electron-hole pairs. In addition, electrochemical impedance spectroscopy (EIS) measurements revealed that the recombination of photogenerated electron-hole pairs was inhibited as the bias potential was applied. Results of Bode plot further demonstrated that the electron lifetime τel of Cu2O/TNAs-20 (30.79 ms), under 0.5 V bias potential, was about 2.23 times higher than that of pure TNAs (13.82 ms). Results of electron spin resonance (ESR) analyses demonstrate that the hydroxyl radicals (OH) are responsible for the PEC decomposition of Ibuprofen.

Aromatic amine contents, component distributions and risk assessment in sludge from 10 textile-dyeing plants

Aromatic amines (AAs), which are components of synthetic dyes, are recalcitrant to the wastewater treatment process and can accumulate in sludge produced by textile-dyeing, which may pose a threat to the environment. A comprehensive investigation of 10 textile-dyeing plants was undertaken in Guangdong Province in China. The contents and component distributions of AAs were evaluated in this study, and a risk assessment was performed. The total concentrations of 14 AAs (Σ14 AAs) varied from 11 μg g(-1)dw to 82.5 μg g(-1)dw, with a mean value of 25 μg g(-1)dw. The component distributions of AAs were characterized by monocyclic anilines, of which 2-methoxy-5-methylaniline and 5-nitro-o-toluidine were the most dominant components. The risk quotient (RQ) value was used to numerically evaluate the ecological risk of 14 AAs in the environment. The result showed that the 14 AAs contents in textile-dyeing sludge may pose a high risk to the soil ecosystem after being discarded on soil or in a landfill.

Improving the remaining activity of lignocellulolytic enzymes by membrane entrapment

The production of bioethanol by the conversion of lignocellulosic waste has attracted much interest in recent years because of its low cost and great potential availability. However, the high cost of the enzyme required for this conversion is often considered to be the major bottleneck in the commercial lignocellulosic ethanol industry. In this work, the hydrolysis of rice straw by free and entrapped lignocellulolytic enzymes (cellulase, xylanase and laccase) was carried out at pH 5.5 and 37°C. The hydrolysis of rice straw by enzymes entrapped in a membrane produced a higher monosaccharide content: 601.05 mg/g rice straw for entrapped enzymes vs. 465.46 mg/g rice straw for free enzymes. This study has shown that enzyme entrapment is an important technique for the efficient use and reuse of enzymes in industrial applications and also for the rapid separation of saccharide products from the reaction medium, thus improving the remaining enzymatic activities.

UV/ozone degradation of gaseous hexamethyldisilazane (HMDS)

As a carcinogen, hexamethyldisilazane (HMDS) is extensively adopted in life science microscopy, materials science and nanotechnology. However, no appropriate technology has been devised for treating HMDS in gas streams. This investigation evaluated the feasibility and effectiveness of the UV (185+254nm) and UV (254nm)/O(3) processes for degradation of gaseous HMDS. Tests were performed in two batch reactors with initial HMDS concentrations of 32-41mgm(-3) under various initial ozone dosages (O(3) (mg)/HMDS (mg)=1-5), atmospheres (N(2), O(2), and air), temperatures (28, 46, 65 and 80 degrees C), relative humilities (20%, 50%, 65%, 99%) and volumetric UV power inputs (0.87, 1.74, 4.07 and 8.16Wl(-1)) to assess their effects on the HMDS degradation rate. Results indicate that for all conditions, the decomposition rates for the UV (185+254nm) irradiation exceeded those for the UV (254nm)/O(3) process. UV (185+254nm) decompositions of HMDS displayed an apparent first-order kinetics. A process with irradiation of UV (185+254nm) to HMDS in air saturated with water at temperatures of 46-80 degrees C favors the HMDS degradation. With the condition as above and a P/V of around 8Wl(-1), k was approximately 0.20s(-1) and a reaction time of just 12s was required to degrade over 90% of the initial HMDS. The main mechanisms for the HMDS in wet air streams irradiated with UV (185+254nm) were found to be caused by OH free-radical oxidation produced from photolysis of water or O((1)D) produced from photolysis of oxygen. The economic evaluation factors of UV (185+254nm) and UV (254nm)/O(3) processes at different UV power inputs were also estimated.

Primary myelodysplasia occurring in adults under 50 years old: a clinicopathologic study of 52 patients

Although myelodysplastic syndromes (MDSs) are generally thought to be diseases of elderly patients, younger patients also have rarely been diagnosed with MDS. This is a report of the clinical, morphologic and cytogenetic features of 52 cases of primary MDS occurring in adults under the age of 50 years. Cases secondary to chemotherapy or radiotherapy were excluded. There were 31 males and 21 females. The median age at presentation was 39 years (range, 18 to 49 years). The interval between onset of symptoms and diagnosis was brief (median, 4 weeks; range, 1-32 weeks). Of the 49 patients for whom information about duration of symptoms was available, 13 (27%) were asymptomatic. Forty-two (81%) of the patients were classified using FAB criteria for blood and bone marrow morphology: refractory anemia (RA), 11; refractory anemia with ringed sideroblasts (RARS), four; refractory anemia with excess blasts (RAEB), 12; chronic myelomonocytic leukemia (CMML), three; refractory anemia with excess blasts in transformation (RAEB-T), 12 patients. Ten patients could not be categorized. Abnormalities involving chromosome 7 was the most frequent cytogenetic abnormality (31%). Partial chromosomal deletion and chromosome gain were also common abnormalities (22% and 9%, respectively). Translocations accounted for only 9% of the main cytogenetic abnormalities encountered in this patient population. For the 49 patients for whom information regarding AML transformation was available, 23 (47%) progressed to acute myeloid leukemia, with an overall median time to progression of 2 months (range 3 weeks to 3 years). In each category except for RARS, approximately half of the patients progressed, with a slightly less median time to progression in RAEB-T than for the other subtypes of MDS. Thirteen patients underwent bone marrow transplantation at the time of presentation of their disease.

Histological and immunohistochemical characterization of extranodal diffuse large-cell lymphomas with prominent spindle cell features

AIMS

To describe five cases of diffuse large-cell lymphoma with prominent spindle cell components involving skin, nasal-ocular mucosa, and soft tissue. Because of the spindle cell morphology, such cases must be differentiated from true sarcomas arising in or metastasizing to soft tissue, skin, bone, lymph node, or other organs and sites.

METHODS AND RESULTS

Formalin-fixed paraffin-embedded archival tissue from five consultation cases of diffuse large-cell lymphoma with prominent spindle cell features involving the skin, nasal-ocular mucosa, and soft tissue in three male and two female patients was studied by histology and immunohistochemistry. Clinicopathological findings were also reviewed for all the patients. By morphology, initial evaluation of the cases suggested spindle cell sarcoma in two cases, inflammatory pseudotumour in one case, large-cell lymphoma in another case, and one case was considered suspicious for malignant lymphoma. Immunohistochemistry demonstrated a B-cell lineage in four of the spindle cell lesions, with a diagnosis of primary cutaneous CD30+ anaplastic large cell lymphoma made for the fifth case. Four of five cases also showed actin reactivity.

CONCLUSIONS

Although extremely rare, lymphomas with prominent spindle cell morphology can be encountered in daily surgical pathology practice, and should be included in the differential diagnosis of spindle cell lesions in skin and soft tissue. The observed actin reactivity in four of the five spindle cell lymphomas may lead to a misdiagnosis of leiomyosarcoma if lymphoid markers are not included in the immunohistochemical panel.

Kinetics and products of the degradation of chitosan by hydrogen peroxide

Low concentrations of hydrogen peroxide induced random degradation of partially deacetylated chitin and chitosan. Average molecular weight decreased in accordance with first-order kinetics. The degradation rate was much faster than that of the ultrasonic degradation, and it was comparable to that of the enzymatic hydrolysis of chitosan. Chain-end scissions occurred after chitosan was degraded severely and produced significant amounts of oligosaccharides at temperatures > or =80 degrees C. Universal calibration moderated the change in molecular weight more closely than that calculated by the usual calibration using pullulan standards. Trace amounts of transition metal ions and the amino groups in chitosan were critical to the breakdown of the beta-1,4 glycosidic linkages. HPLC results of glucosamine and chito-oligosaccharides could be characterized by correlating the logarithmic values of retention time with the degrees of polymerization. The formation of glucosamine and chito-oligosaccharides depended on the concentration of H(2)O(2), temperature, and the physicochemical property of chitin/chitosan.

Diagnostic utility of microphthalmia transcription factor in malignant melanoma and other tumors

The diagnosis of malignant melanoma is sometimes challenging. Immunohistochemistry for specific markers of melanocytic differentiation such as HMB-45 and Melan-A can be very valuable in proving melanocytic differentiation in poorly differentiated or spindled forms of melanoma. Microphthalmia-associated transcription factor (MiTF) is the most recently described and the only nuclear melanocytic marker. This article reviews the biology of MiTF and those published studies that have addressed its diagnostic sensitivity and specificity. MiTF may be very valuable for the diagnosis of melanoma, including desmoplastic variants; melanocytic soft tissue tumors, such as clear cell sarcoma; and the unusual group of tumors that show combined melanocytic and myoid differentiation, the perivascular epithelioid cell family of tumors (PEComas).

Comparison and clinical application of frequency domain methods in analysis of neonatal heart rate time series

The frequency content of the heart rate (HR) series contains information regarding the state of the autonomic nervous system. Of particular importance is respiratory sinus arrhythmia (RSA), the high-frequency fluctuation in HR attributable to respiration. The unevenly sampled nature of heart rate data, however, presents a problem for the discrete Fourier transform. Interpolation of the HR series allows even sampling, but filters high-frequency content. The Lomb periodogram (LP) is a regression-based method that addresses these issues. To evaluate the efficacy of the LP and Fourier techniques in detecting RSA, we compared the spectrum of intervals, the spectrum of HR samples, and the LP of simulated and clinical neonatal time series. We found the LP was superior to the spectrum of intervals and the spectrum of HR samples in analysis near the critical frequency of one half the average sampling rate. Applying the LP to clinical data, we found (1) evidence of stochastic resonance, an enhancement of periodicity with the addition of small amounts of noise, and (2) reduced power at all frequencies prior to clinical diagnosis of neonatal sepsis.

No significant association of Epstein-Barr virus infection with invasive breast carcinoma

We studied 48 cases of invasive breast carcinoma for evidence of Epstein-Barr virus (EBV), which is associated with many human malignancies. In situ hybridization studies to detect the presence of EBV-encoded small nonpolyadenylated RNA (EBER)-1 were performed in paraffin sections. Immunohistochemical studies to detect EBV nuclear antigen (EBNA)-1, latent membrane protein (LMP)-1, and the transactivating immediate-early BZLF1 (ZEBRA) protein were also performed in paraffin sections. The presence of EBV genomic DNA was studied by polymerase chain reaction (PCR) amplification using sets of primers flanking the EBNA-4 and the EBV-LMP-1 genes in frozen tissues. Southern blot analysis using a probe flanking the EBV terminal repeat region was then attempted in cases that were PCR-positive. Five of 48 cases (10%) of breast carcinoma showed focal EBER-positive tumor cells. Twelve cases (25%) were positive for EBNA-1 by immunohistochemistry, all but one different from the EBER-positive cases. None of the cases were positive for LMP-1 or ZEBRA protein by immunohistochemistry. PCR studies for EBNA-4 and LMP-1 were each positive in five cases (including three cases in common). However, Southern blot studies successfully performed in all but one of the PCR-positive cases were completely negative. The identification of EBV by any methodology was not correlated with tumor size, grade, or lymph node status. This study demonstrated evidence of EBV infection in tissues involved by invasive breast carcinomas in a significant subset of cases. However, the lack of localization of EBV infection to a significant population of the tumor cells in any case, the negativity by Southern blot hybridization, and the lack of expression of multiple antigens in any case strongly argue against a significant role for EBV in the pathogenesis of breast carcinoma.

Arginase levels are increased in patients with rheumatoid arthritis

Arginase and nitric oxide synthase (NOS) compete for the same substrate, L-arginine. The reciprocal regulation of arginase and NOS in L-arginine-metabolizing pathways has recently been demonstrated. Since NOS is involved in the inflammation of human arthritides, we hypothesized that this reciprocal regulation might also occur within the inflamed synovium. The present study shows that both serum arginase activity and protein levels were significantly higher in patients with rheumatoid arthritis (RA) than in patients with systemic lupus erythematosus (SLE) or osteoarthritis (OA) or in healthy controls. Arginase protein concentrations in supernatants of monocyte cultures from RA patients were also significantly higher than in those from SLE or OA patients or healthy controls. In RA patients, there was a significant correlation between the serum concentrations of arginase protein and rheumatoid factor (r = 0.82, p < 0.0001). These data indicate that increased arginase production is seen in RA patients, but not in other immune-related diseases, suggesting that increased arginase production is unique to, and may play an important role in, the pathogenesis of RA disease.

Utility of CD10 in Distinguishing between Endometrial Stromal Sarcoma and Uterine Smooth Muscle Tumors: An Immunohistochemical Comparison of 34 Cases

Endometrial stromal sarcoma (ESS), uterine cellular leiomyoma (UCL), and uterine leiomyosarcoma (ULS) are composed mainly of spindle cells that express similar antigens such as desmin, smooth muscle actin (SMA), and muscle-specific actin (MSA). The differential diagnosis of an ESS versus a uterine smooth muscle tumor or an extrauterine spindle cell sarcoma can be problematic based solely on clinical presentation, histologic assessment, or routine immunohistochemistry. Recently, we reported that normal endometrium, but not myometrium, as well as five cases of ESS, were positive for CD10. We now report the results of CD10 immunohistochemistry in an additional 11 cases of ESS (total 16 cases), 10 cases of UCL, and nine cases of ULS. CD10 immunoreactivity was detected in 16 of 16 cases of ESS (100%) as compared to only 2 of 10 cases of UCL (20%) and none of nine cases of ULS (0%). We compared the utility of CD10 immunoreactivity with that of desmin, SMA, MSA, estrogen receptor (ER), and inhibin in these tumors. Although the majority of cases of UCL and ULS were positive for SMA, MSA, and desmin, a substantial portion of cases of ESS were also positive for SMA, MSA, and desmin. We conclude that in combination with SMA, MSA, and desmin, CD10 is a useful immunohistochemical marker in the differential diagnosis of ESS versus UCL or ULS.

The effects of arecoline on the release of cytokines using cultured peripheral blood mononuclear cells from patients with oral mucous diseases

In Taiwan there is a significant correlation between oral precancer diseases and oral cancer associated with the betel quid chewing habit. The carcinogenic components of betel quid are arecoline, arecaidine and safrole. However, it is unknown whether these substances influence the immune functions. This study investigated the effects of betel quid on the immune system using cultured peripheral blood mononuclear cells from patients with oral mucous diseases. In our experiment, mononuclear cells from 10 normal persons, 12 patients with precancer lesions, and 16 patients with squamous cell carcinoma were separated from blood samples and cultured. After stimulation by arecoline, the amounts of IL-2, TNF-alpha, TGF-beta and IFN-gamma secreted by mononuclear cells were measured using the ELISA method. The results showed that IL-2, TNF-alpha, and TGF-beta were significantly lower in mononuclear cells of normal persons as stimulated by arecoline. The TGF-beta amount in cells from oral submucous fibrosis patients with betel quid chewing habit (OSF-B) was lower than normal persons or patients who had long term betel quid chewing habit but were without oral mucosal diseases (N-B), and was also lower than the squamous cell carcinoma with betel quid chewing group (SCC-B). TNF-alpha was significantly lower in the squamous cell carcinoma with long term betel quid chewing group (SCC-B) than in normal persons. TNF-alpha was significantly higher in the squamous cell carcinoma without betel quid chewing group (SCC-N) than in normal persons and SCC-B groups. In addition, IFN-gamma was significantly lower in patients who had long term betel quid chewing but were without oral mucous lesions than the normal person and the OSF group. The results proved that betel quid influences cytokines production by mononuclear cells.

Development of a sandwich ELISA test for arginase measurement based on monoclonal antibodies

Human arginase was purified from liver and two monoclonal antibodies (MAbs), HA1 and HA2, were produced by fusion of spleen cells from an arginase-immunized BALB/c mouse and the NS-1 myeloma cell line. Both MAbs were of the IgG3 subclass and contained the kappa light chain. HA1 inhibited arginase activity, suggesting that it binds to the arginase catalytic site. HA1 and a horseradish peroxidase-conjugated polyclonal rabbit anti-human arginase antibody were used to develop a sandwich enzyme-linked immunoadsorbent assay (ELISA) for the quantification of human arginase, which can be used in the 1 to 300 ng/mL range. Because of its sensitivity and specificity, this MAb can be successfully applied to the ELISA quantification of arginase in serum and culture supernatants.

Immunohistochemical detection of CD10 in paraffin sections of hematopoietic neoplasms: a comparison with flow cytometry detection in 56 cases

Paraffin-section immunohistochemistry with heat-induced epitope retrieval using a newly characterized monoclonal antibody (clone 56C6) against the CD10 antigen was performed on 56 hematopoietic tumors previously studied for CD10 expression by flow cytometry. The cases included 33 precursor B-lymphoblastic leukemias, 10 acute myeloid leukemias, five precursor T-lymphoblastic leukemias, five follicular lymphomas, and three Burkitt cell leukemias. Forty of the 56 cases were CD10 positive by flow cytometry studies, including all five follicular lymphomas (100%); 30 of 33 (91%) cases of precursor B-lymphoblastic leukemias, two of three (66%) cases of Burkitt cell leukemias, two of five (40%) cases of precursor T-lymphoblastic leukemias, and none of the 10 cases of acute myeloid leukemia. Thirty-nine of the 40 (97%) flow cytometric CD10-positive cases also expressed CD10 by immunohistochemistry in formalin- or B5-fixed, paraffin-embedded tissue, with only one case of precursor B-lymphoblastic leukemia being positive by flow cytometry and negative by immunohistochemistry. The 16 CD10-negative flow cytometry specimens were all also negative by immunohistochemistry. Thirty-seven CD10 immunohistochemistry positive cases showed a diffuse membranous staining pattern and two cases demonstrated a Golgi staining pattern. The fixation methods (10% neutral buffered formalin versus B5) and decalcification did not affect the CD10 immunostaining results. This study demonstrates that the new CD10 monoclonal antibody clone 56C6 is a reliable marker for detection of CD10 antigen expression in formalin-and B5-fixed paraffin-embedded tissue after heat-induced epitope retrieval when compared with flow cytometry detection of fresh tissue samples.

Immunophenotyping of hematopoietic neoplasms

Advances in the staging and treatment of hematopoietic neoplasms have necessitated a high degree of accuracy in the diagnosis and classification of these tumors. A greater degree of diagnostic precision has resulted from recent advances in immunophenotyping and genotyping of hematopoietic neoplasms. This review discusses several new immunohistochemical reagents, many of which are derived from results of molecular studies.

The use of archival bone marrow specimens in detecting B-cell non-Hodgkin's lymphomas using polymerase chain reaction methods

The detection of B-cell non-Hodgkin's lymphoma (B-NHL) involving the bone marrow (BM) can be enhanced by assessing immunoglobulin heavy chain (IgH/JH) gene rearrangement using PCR. While the fresh BM aspirate has been the most commonly used specimen, the utility of archival BM tissues has not been extensively evaluated. We studied the BM from 13 patients with nodal B-NHL (7 low-grade and 6 intermediate grade), which were categorized into three groups based on the histologic finding of lymphoma (H) and the presence of a monoclonal IgH/JH band by PCR using fresh BM aspirates (M): (1) H(+)/M(+), 4 cases; (2) H(+)/M(-), 4 cases; and (3) H(equivocal)/M(-), 5 cases. Archival tissues available for study included paraffin-embedded trephine biopsy (TB)/aspirate clots (AC) and air-dried aspirate smears (AS). All TB (13/13) and a subset of AC (5/13) were B5-fixed, and all these tissues failed to yield analyzable DNA. In contrast, sufficient DNA was consistently obtained in AC that were formalin-fixed (8/13). Of these 8 cases, 2/3 of group 1, 3/3 of group 2, and 0/2 of group 3 had a monoclonal IgH band. Using DNA extracted from microdissected lymphoid aggregates morphologically evident in the AC sections, additional positive cases were identified: 1/3 of group 1 and 2/2 of group 3. In those 5 cases that did not have formalin-fixed TB/AC, sufficient DNA was extracted from AS in all cases; one additional positive case was identified in group 1. Overall, 4/4 (100%) of group 1, 3/4 (75%) of group 2, and 2/5 (40%) of group 3 showed molecular evidence of lymphoma. To conclude, archival BM specimens are a useful source of DNA for molecular detection of B-NHL involvement, and formalin appears to be a better fixative than B5. The use of these samples may improve the overall detection sensitivity.

Nasal glomus tumors: report of two cases with emphasis on immunohistochemical features and differential diagnosis

We describe 2 cases of nasal glomus tumor that presented as nasal polyps. Grossly, each of the polypectomy specimens consisted of small fragments of polypoid soft tissue with glistening mucosa. Histopathological examination of each of the specimens showed sheets and nests of monomorphic round cells intimately associated with capillary-sized blood vessels. The tumor cells were strongly cytoplasmic positive for vimentin, smooth-muscle specific actin, muscle-specific actin, and CD34. Collagen IV showed pericellular positivity. Nasal glomus tumors are extremely rare and represent less than 0.5% of nasal nonepithelial tumors. Nasal polyps are common surgical pathological specimens, with the majority of nasal polyps being inflammatory polyps or a respiratory epithelial proliferation. Histologically, many nasal polyps show vascular proliferation with an inflammatory cell infiltrate, which may be confused with the rare glomus tumor. In addition, other nasal vascular tumors, in particular nasal hemangiopericytoma and neural tumors, may histologically mimic nasal glomus tumors.

Epstein-Barr virus (EBV) nuclear antigen (EBNA)-4 mutation in EBV-associated malignancies in three different populations

Different ethnic groups with a high human leukocyte antigen (HLA)-A11 prevalence have been shown to experience a high rate of Epstein-Barr virus (EBV) infection, EBV-associated malignancies, and Epstein-Barr nuclear antigen (EBNA)-4 mutations. The epitopes 399-408 and 416-424 of EBNA-4 are major antigenic epitopes that elicit an HLA-A11 cytotoxic T lymphocyte (CTL) response to EBV infection. Mutations selectively involving one or more nucleotide residues in these epitopes affect the antigenicity of EBNA-4, because the mutant EBV strains are not recognized by the HLA-A11-restricted CTLs. To investigate these mutations in common EBV-associated malignancies occurring in different populations, we studied the mutation rate of epitopes 399-408 and 416-424 of EBNA-4 in 25 cases of EBV-associated Hodgkin's disease (HD), nine cases of AIDS-related non-Hodgkin's lymphoma, and 37 cases of EBV-associated gastric carcinoma (GC) from the United States, Brazil, and Japan. We found one or more mutations in these two epitopes in 50% (6/12) of United States HD, 15% (2/13) of Brazilian HD, 50% (6/12) United States GC and 28% (7/25) Japanese GC, and 22% (2/9) of United States AIDS-lymphoma. Similar mutations were found in 30% (3/10) of United States reactive, 0% (0/6) of Brazilian reactive, and 25% (2/8) Japanese reactive tissues. The most frequent amino acid substitutions were virtually identical to those seen in previously reported isolates from EBV-associated nasopharyngeal carcinomas and Burkitt's lymphomas occurring in high prevalence HLA-A11 regions. However, only 2/28 (7%) mutations occurred in HLA-A11-positive patients. Our studies suggest that: 1) EBNA-4 mutations are a common phenomenon in EBV-associated HD, GC, and AIDS-lymphoma; 2) the mutation rate does not vary in these geographic areas and ethnic groups; 3) EBNA-4 mutations in EBV-associated United States and Brazilian HD, United States and Japanese GC, and United States AIDS lymphomas are not related to patients' HLA-A11 status.

Identification of a new single nucleotide substitution on the hypoxanthine-guanine phosphoribosyltransferase gene (HPRT(Tsou) from a Taiwanese aboriginal family with severe gout

OBJECTIVE

A new single nucleotide change of the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene on coding region has been identified from a Taiwanese aboriginal family with gout. The mutation was used to screen 27 members of the family, 22 Tsou, 70 Atayal, and 76 Bunun children, the elders for whom had been found to have a high prevalence of gout.

METHODS

An entire peptide of HPRT coding region was directly sequenced from the cDNA of a patient with severe gout, and by using polymerase chain reaction and restriction fragment length polymorphism to screen the other participants.

RESULTS

A new nucleotide change located at nucleotide 152 (G to A transition) was found that predicted an arginine to glutamine substitution at amino acid 51. This variant was named HPRT(Tsou), and was found in 3 women and 3 men among the patient's 7 siblings, 2 boys and 2 girls among the 8 children of the siblings, and one female Tsou (4.5%, 1/22) and one female Atayal (1.4%, 1/70). The serum uric acid concentration among male HPRT(Tsou) carriers in the patient's family was significantly higher than among those who had at least one HPRT gene that did not have HPRT(Tsou).

CONCLUSION

We found that the HPRT(Tsou) gene variant is partially responsible for the hyperuricemia in an aboriginal population in Taiwan known for a high incidence of gout.