Photooxidation of azo dye reactive black 5 using a novel supported iron oxide: heterogeneous and homogeneous approach.

Photooxidation of azo dye Reactive Black 5 (RB5) by H202 was performed with a novel supported iron oxide in a batch reactor in the range of pH 2.5-6.0. The iron oxide was prepared through a fluidized-bed reactor (FBR) and much cheaper than the Nafion-based catalysts. Experimental results indicate that the iron oxide can significantly accelerate the degradation of RB5 under the irradiation of UVA light (wavelength = 365 nm). An advantage of the catalyst is its long-term stability, which was confirmed through using the catalyst for multiple runs in the degradation of RB5. In addition, this study focused mainly on determining the proportions of homogeneous catalysis and heterogeneous catalysis in the batch reactor. Conclusively, although heterogeneous catalysis contributes primarily to the oxidation of RB5 during pH 4.5-6.0, the homogeneous catalysis is of increasing importance below pH 4.0 because of the Fe ions leaching from the catalyst to solution.

Novel activated alumina-supported iron oxide-composite as a heterogeneous catalyst for photooxidative degradation of reactive black 5.

A novel activated alumina-supported iron oxide-composite (denoted as FeAA-500) was prepared by so-called fluidized-bed reactor (FBR) crystallization. X-ray powder diffraction (XRD), N2 adsorption/desorption, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to characterize the FeAA-500. The photo-catalytic activity of the FeAA-500 was evaluated in the photooxidative degradation of 0.1 mM azo-dye reactive black 5 (RB5) in the presence of H2O2 and UVA light (lambda = 365 nm) in a solution with a pH of 2.5. Complete decolorization of the model pollutant RB5 was achieved; the total organic carbon (TOC) removal ratio was 95%, and a trace amount of leached ferric ion was detected following 75 min of reaction when 2.0 g/L FeAA-500 was used as a catalyst. FeAA-500 has high photo-catalytic activity; it is therefore a promising heterogeneous photocatalysis of the degradation of organic compounds.

Degradation of azo dyes using low iron concentration of Fenton and Fenton-like system.

This study investigated Fenton and Fenton-like reactions at low iron concentration (

Treatment of non-biodegradable wastewater by electro-Fenton method.

A novel electro-Fenton method, called the Fered-Fenton method, applying H2O2 and electrogenerated ferrous ions for treating organic-containing wastewater was investigated. By combining electrochemical reduction and chemical oxidation, the process can regenerate ferrous ions and remove organic compounds simultaneously in a batch reactor. Because the generation rate of ferrous ions is one of the key parameters in evaluating the oxidation efficiency of the reaction system, the initial current efficiencies (eta(i)) for iron (III) reduction are examined first. It shows that increasing initial ferric ion concentration can achieve high initial current efficiency. In addition, eta(i) decreased (ca. 20-100%) with increasing current density of cathode (ca. 40-199 A/m2). For illustration, the wastewater from chemical (i.e. electroless) nickel plating was treated in this investigation owing to its non-biodegradability and high organic concentration. The average pH, COD and Ni concentrations of this wastewater were about 5.0, 30,000 and 2,000 mg/L, respectively. Experimental results indicate that traditional Fenton method only removed 60% of COD when using 5,000 mg/L of ferrous ions. However, the COD removal efficiency was promoted after the electricity was introduced into the system (i.e. Fered-Fenton method). Moreover, Ni concentration was reduced from 2,080 to 0.3 mg/L, indicating that the removal efficiency was higher than 99.9%.

Glial fibrillary acidic protein immunoreactivity of chondrocytes in immature and mature teratomas.

The immunoreactivity of chondrocytes for glial fibrillary acidic protein (GFAP), other intermediate filament proteins and S-100 protein was studied in formalin-fixed paraffin-embedded sections. A total of 95 cartilage specimens were examined from five immature teratomas, 12 mature teratomas, and a teratocarcinoma. GFAP-immunoreactive chondrocytes were abundant in immature cartilages, and as the cartilages maturated, these chondrocytes decreased and became distributed peripherally. Elastic cartilage had more GFAP-immunoreactive chondrocytes than non-elastic cartilage. GFAP-immunoreactive cartilage was often located close to central nervous tissue. Immunostaining for vimentin and S-100 protein revealed extensive distribution of immunoreactive chondrocytes in immature and mature cartilages, but in mature cartilage, chondrocytes at the center had less vimentin immunoreactivity. GFAP-immunoreactive chondrocytes also showed apparent immunostaining for vimentin. There was no difference in immunohistochemical staining for the alpha and beta subunits of S-100 protein. The immunoreactivities of teratoma cartilage specimens were quite similar to those of respiratory tract cartilage.

Importance of immunoenzyme histochemical reaction in diagnosis of disseminated intravascular coagulation in human and animal material.

Renal tissues from 208 human necropsies were observed histologically for disseminated intravascular coagulation (DIC). The tissues were stained with hematoxylin-eosin, Mallory's phosphotungstic acid hematoxylin (PTAH) and cationic ferric hydroxide colloid stabilized with cacodylate (Fe-Cac), and tested by immunoenzyme histochemical (IEH) reaction for fibrin-related materials (FRMs). The use of the IEH method increased FRM recognition, and FRMs were detected in a total of 80 cases (38.5%). In 26 cases diagnosed clinically as DIC, FRMs were shown in 23 of the cases (88.5%). Thus, 57 patients with FRMs were clinically asymptomatic. In rats with DIC induced by endotoxin injection, glomerulus FRM was effluxed into the tubulus through the Bowman's capsule and was excreted into urine. The electric charge was reduced on the endothelial surface of the glomerular capillaries in both human and rat DIC. Under the scanning electron microscopy, the endothelial surface appeared coarse in the glomerular capillary and fibrin degradation was present. Our conclusions are: (a) PTAH is non-specific for FRMs, (b) IEH aids the pathohistological diagnosis of DIC, especially in asymptomatic forms including the compensated DIC state, (c) FRMs in tubuli suggest DIC, and (d) DIC is possibly initiated by a reduction in the capillary electric surface charge.

A new method of the immunohistochemical detection of cellular antigens for light and electron microscopy.

A new immunohistochemical method for light and electron microscopy of tissue- and cell-specific antigens by using ferric colloid-labeled antibody is presented. The antibodies labeled with the cationic cacodylate ferric colloid are stable and bind specifically to the target antigens to show clearly the site of antigens in tissue sections and on free cells by Prussian blue reaction for light microscopy and by the specific figure of electron opaque ferric colloid particles for electron microscopy. The staining procedure is very simple and it gives clear picture. So the method will be of beneficial for general laboratory use in immunohistochemical researches.

Merkel cell tumor coexpressing cytokeratin and neurofilament proteins.

Whorled filaments 10 nm in width were identified by anti-intermediate filaments antibodies in a Merkel cell tumor from a 52-year-old man. Immunohistochemical tests revealed that the tumor was stained with anti-keratin antibody and antibodies against the 68-kd and 200-kd subunits of neurofilament proteins but not antibody against the 150-kd subunit. This is the first reported case of Merkel cell tumor expressing a 200-kd subunit of neurofilament proteins.

Primary malignant lymphoma of the breast. With a review of 73 cases among Japanese subjects.

We report a case of a 71-year-old female with primary malignant lymphoma of the breast. The patient noticed a lump in the right breast approximately six years prior to consultation to the Surgical Department because of a rapid growth of the lump, and had no other tumors noticed throughout the body during that period. Histology proved the case to be a "reticulum cell sarcoma" (large cell type) producing IgM in the tumor cells, instead of a breast carcinoma as clinically diagnosed. At the same time, a total of 73 cases of mammary malignant lymphoma among Japanese subjects were reviewed. The criteria for primary or secondary malignant lymphoma of the breast, and histological diagnosis and pathogenesis of the primary breast malignant lymphoma were discussed.

Induction of hemopoiesis in rat embryonic bone transplanted into adult subcutaneous connective tissue.

Five pairs of immature, non-hemopoietic femur and tibia from 17-day-old gestating female rat fetuses, whose sex was determined by chromosomal analysis of liver cells, were transplanted into subcutaneous tissues of adult male rats. The original bones were about 3 mm in length and they grew to about 17 mm length at 4 wereks after transplantation. Bone deformation was not evident after transplantation and bone marrow hemopoiesis developed. Bone marrow cytohistologic observations were made on smears, and chromosome analyses were performed on bone marrow cells. Active erythro-, myelo- and megakaryopoiesis were conducted by cells of recipient adult rats. Sex chromosome analysis of cartilage cells from the epiphyses of transplanted bones demonstrated that the growing bones were composed of cells from the grafted embryo. The results thus strongly suggest that the transition of hemopoiesis from liver to bone marrow in late embryonic development is conducted by stem cells migrating through circulating blood and settling in the bone marrow and not by in situ cells differentiating in the bone marrow stroma.

Hemopoietic recovery in bone marrow of lethally irradiated rats following parabiosis. I. Granulopoiesis.

Aplasia was induced in rats by total body irradiation. Three days later, the animal was conjugated by aortic anastomoses with a healthy untreated litter-mate. 6 h after parabiosis, the bone marrow of irradiated animals contained some granulocytes showing RNA synthesis. At 18 h, many myelocytes and promyelocytes were present but no myeloblast was encountered. These myeloid precursor cells showed active DNA synthesis but no mitoses, and no erythroblasts were observed at this time period. At 24 h, mitoses of myeloblasts were found. At 42--60 h, erythropoiesis was evident. Chromosome analysis and investigations of cells of irradiated parabionts conjugated with partners having labeled cells, revealed that these newly formed myeloid and erythroid cells originated from the untreated parabiont. The mechanism of triggering myelopoiesis in the aplastic bone marrow by parabiosis is discussed.