ZnO nanorod arrays assembled on activated carbon fibers for photocatalytic degradation: Characteristics and synergistic effects.

Well-aligned ZnO nanorod arrays were assembled on activated carbon fibers by a stepwise sequence of sol-gel and hydrothermal synthesis methods. These ZnO nanorod arrays on activated carbon fibers having different characteristics such as surface area, rod concentration, aspect ratio and defect level, were applied as catalysts for the photodegradation of an aqueous methylene blue solution. They showed very promising methylene blue adsorbility in the dark (ca.

An in situ ATR-IR spectroscopy study of aluminas under aqueous phase reforming conditions.

High temperature/pressure in situ Attenuated Total Reflection Infrared (ATR-IR) spectroscopy was used to investigate the phase transformation of support γ-Al2O3 into boehmite (AlO(OH)) under the hydrothermal conditions of aqueous phase reforming (APR). Activation energy barriers of boehmite formation in hot compressed water at temperatures between 150 and 180 °C were calculated to be 15.9 ± 4.

Towards stable catalysts for aqueous phase conversion of ethylene glycol for renewable hydrogen.

Aqueous-phase reforming of ethylene glycol over alumina-supported Pt-based catalysts is reported. Performance of the catalysts is investigated by conducting kinetics and in situ attenuated total reflectance (ATR)-IR spectroscopic analysis. Pt/γ-Al2 O3 is unstable under APR conditions (270 °C, 90 bar) and undergoes phase transformation to boehmite [AlO(OH)].

Valorization of humin-based byproducts from biomass processing-a route to sustainable hydrogen.

The synthesis of biomass-based top value-added chemical platforms, for example, 5-hydroxymethyl furfural, furfural, or levulinic acid from the acid-catalyzed dehydration of sugars results in high yields of insoluble by-products, referred to as humin. Valorization of humin by steam reforming for H2 is discussed. Both thermal and catalytic steam gasification were investigated systematically.

Conversion of lignocellulosic biomass to green fuel oil over sodium based catalysts.

Upgrading of biomass pyrolysis vapors over 20 wt.% Na2CO3/γ-Al2O3 catalyst was studied in a lab-scale fix-bed reactor at 500°C. Characterization of the catalyst using SEM and XRD has shown that sodium carbonate is well-dispersed on the support γ-Al2O3.

In situ catalytic pyrolysis of lignocellulose using alkali-modified amorphous silica alumina.

Canadian pinewood was pyrolyzed at 450 °C in an Infrared oven and the pyrolysis vapors were converted by passing through a catalyst bed at 450 °C. The catalysts studied were amorphous silica alumina (ASA) containing alkali metal or alkaline earth metal species including Na, K, Cs, Mg and Ca. The catalysts effectiveness to reduce the bio-oil oxygen content, to enhance the bio-oil energy density and to change the liquid and gas product distribution were evaluated using different techniques including gravimetric analysis, elemental analysis, Karl-Fischer titration, GC/MS and micro-GC analysis.

Presence of lithium ions in MgO lattice: surface characterization by infrared spectroscopy and reactivity towards oxidative conversion of propane.

The surface morphology of Li-promoted MgO catalysts prepared using the sol-gel method (sg) and wet impregnation procedure (imp), respectively, has been studied by low-temperature infrared spectroscopy of adsorbed CO molecules. The results show that step sites, as unselective catalytic centers, are the major features existing on the surface of pure MgO, and those are active toward the oxidative conversion of propane. However, the concentration of these sites is drastically reduced by the incorporation of lithium ions in the MgO lattice.

The role of Candida albicans NOT5 in virulence depends upon diverse host factors in vivo.

We previously identified Candida albicans Not5p as an immunogenic protein expressed during oropharyngeal candidiasis (OPC). In this study, we demonstrate that C. albicans NOT5 reverses the growth defects of a Saccharomyces cerevisiae not5 mutant strain at 37 degrees C, suggesting that the genes share at least some functional equivalence.

A metalloproteinase of Coccidioides posadasii contributes to evasion of host detection.

Coccidioides posadasii is a fungal respiratory pathogen of humans that can cause disease in immunocompetent individuals. Coccidioidomycosis ranges from a mild to a severe infection. It is frequently characterized either as a persistent disease that requires months to resolve or as an essentially asymptomatic infection that can reactivate several years after the original insult.

A parasitic phase-specific adhesin of Coccidioides immitis contributes to the virulence of this respiratory Fungal pathogen.

We report the isolation of a Coccidioides immitis gene (SOWgp) which encodes an immunodominant, spherule outer wall glycoprotein that is presented as a component of a parasitic phase-specific, membranous layer at the cell surface. The open reading frame of the gene from C. immitis isolate C735 translates a 422-amino-acid (aa) polypeptide that contains 6 copies of a 41- to 47-residue tandem repeat enriched in proline (20.

Reintroduction of the PLB1 gene into Candida albicans restores virulence in vivo.

Phospholipases have been proposed to contribute to the virulence of Candida albicans. Recently, a candidal strain deleted for PLB1, the gene encoding the predominant phospholipase B (Plb1) secreted by C. albicans, was constructed and its virulence in an intravenous murine model of disseminated candidiasis was evaluated.

Vital staining of fungal elements in deep-seated mycotic lesions during experimental murine mycoses using the parenterally applied optical brightener Blankophor.

Optical brighteners of the diaminostilbene type are fluorescent dyes which are popular diagnostic tools in the mycology laboratory. While these dyes are conventionally used for the in vitro diagnosis of mycoses, their low toxicity and chemical reactivity have led us to investigate their potential use for in vivo staining of fungal elements in mycotic tissue. In mice we have established deep-seated candidiasis, cryptococcosis, aspergillosis and zygomycosis, as well as coccidioidomycosis, histoplasmosis and blastomycosis.

A major cell surface antigen of Coccidioides immitis which elicits both humoral and cellular immune responses.

Multinucleate parasitic cells (spherules) of Coccidioides immitis isolates produce a membranous outer wall component (SOW) in vitro which has been reported to be reactive with antibody from patients with coccidioidal infection, elicits a potent proliferative response of murine immune T cells, and has immunoprotective capacity in a murine model of coccidioidomycosis. To identify the antigenic components of SOW, the crude wall material was first subjected to Triton X-114 extraction, and a water-soluble fraction derived from this treatment was examined for protein composition and reactivity in humoral and cellular immunoassays. Protein electrophoresis revealed that the aqueous fraction of three different isolates of C.

Retrovirus-induced immunodeficiency in mice exacerbates gastrointestinal candidiasis.

Dysfunction of neutrophils in patients infected with human immunodeficiency virus is at least partly responsible for secondary microbial diseases in these individuals, including invasive gastrointestinal (GI) candidiasis. Immunoregulatory disturbances associated with the development of AIDS in human immunodeficiency virus-infected patients exacerbates Candida albicans infection of the upper GI tract and frequently leads to oropharyngeal and esophageal candidiasis. In this article, we present the first report of a murine model of invasive GI candidiasis associated with an AIDS-related murine immunodeficiency syndrome that results from infection of C57BL/6 mice with a previously described retrovirus complex (LP-BM5).

Isolation and expression of a gene which encodes a wall-associated proteinase of Coccidioides immitis.

A chymotrypsinlike serine proteinase of Coccidioides immitis with an estimated molecular size of 34 kDa has been shown by immunoelectron microscopy to be associated with the walls of the parasitic cells of this human respiratory pathogen. The proteinase has been suggested to play a role in spherule development. We report the isolation of a 1.

Coccidioides immitis fractions which are antigenic for immune T lymphocytes.

The principal mechanism of resistance to coccidioidomycosis in experimental animals has been reported to be T-cell-mediated immunity. We have generated a Coccidioides immitis antigen-specific murine T-cell line to identify specific macromolecules capable of eliciting an immune mouse T-cell proliferative response. The murine T cells were stimulated in vitro with a soluble conidial wall fraction (SCWF), which has been previously characterized by humoral and cellular immunoassays.

Chlamydospore-like cells of Candida albicans in the gastrointestinal tract of infected, immunocompromised mice.

We have demonstrated in a previously described murine model of gastrointestinal (GI) and systemic candidiasis that the antifungal angent cilofungin was efficacious in clearing infection of body organs when administered subcutaneously by infusion, but permitted large numbers of Candida albicans in the GI tract to persist. Yeast and hyphae in these animals were associated primarily with the stratified squamous epithelium of the stomach. Administration of immunocompromising drugs (cyclophosphamide plus cortisone acetate) to animals with persistent GI infection resulted in relapse of systemic candidiasis.

Antigen complex of Coccidioides immitis which elicits a precipitin antibody response in patients.

The occurrence in patients of elevated levels of immunoglobulin M (IgM) precipitin antibody to Coccidioides immitis antigens, which are commonly detected by the immunodiffusion-tube precipitin (TP) assay, is suggestive of primary nondisseminating coccidioidomycosis. We previously demonstrated that the concanavalin A-bound mycelial culture filtrate plus lysate preparation is a source of at least two TP antibody-reactive antigens (TP-Ags), which were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis as 120- and 110-kDa fractions. Evidence is presented here that the crude filtrate plus lysate preparation contains additional lectin-bound, TP antibody-reactive fractions as well as a component which elicits a complement fixation antibody response in patients.

Evaluation of a murine model of hepatic candidiasis.

A murine model of focal hepatic candidiasis which we suggest simulates certain conditions of this clinical variant of systemic candidiasis in leukemic patients is described. We have shown that outbred mice inoculated with Candida albicans by the oral-intragastric route as infants (6 days old) and then immunocompromised by cyclophosphamide and cortisone acetate treatment 2 weeks later demonstrate systemic spread of the opportunistic pathogen to the liver, lungs, spleen, and kidneys. Treatment with the immunosuppressive drugs cyclophosphamide and cortisone acetate resulted in alteration of the normal integrity of the mucosal epithelium of the gut as well as in granulocytopenia.

An animal model for oropharyngeal, esophageal and gastric candidosis.

Conventional mice inoculated with Candida albicans by the oral-intragastric route as infants (6-day-old) have previously been shown to develop gastrointestinal (GI) candidosis which persists for at least 30-60 days post-challenge without the use of compromising procedures. Histological preparations of the stomachs of these animals reveal hyphae which have crossed the mucin barrier and are associated with the stratified squamous epithelium of the gastric mucosa primarily in the region of the cardial-atrium fold. Host inflammatory cells are frequently observed adjacent to these filaments and yeast cells.

Composition, serologic reactivity, and immunolocalization of a 120-kilodalton tube precipitin antigen of Coccidioides immitis.

Diagnosis of coccidioidomycosis largely depends on serologic tests. In this investigation, the enzyme-linked immunosorbent assay (ELISA) was used to detect patient immunoglobulin M (IgM) precipitin antibody binding to a 120-kilodalton (kDa) fraction previously isolated from an alkali-soluble, water-soluble extract of the arthroconidial wall and mycelial culture filtrate plus toluene lysate of Coccidioides immitis. Results of the serologic response to this tube precipitin antigen (TP-Ag) in the ELISA correlated well with results of immunodiffusion assays of 30 serum samples from patients.

Gastrointestinal and systemic candidosis in immunocompromised mice.

Oral-intragastric inoculation of 6-day-old outbred Crl:CFW(SW) BR mice with Candida albicans can lead to colonization of the gastrointestinal (GI) tract. We have shown that in the absence of an immunocompromising treatment, Candida is primarily localized in the stomach and intestines of mice at 20 days post-inoculation. Cultures of homogenates of the esophagus of most animals tested, and homogenates of the liver, lungs, spleen and kidneys of all animals tested, proved negative for C.

Isolation and morphology of an immunoreactive outer wall fraction produced by spherules of Coccidioides immitis.

A previously undescribed, immunoreactive, membranous spherule outer wall (SOW) fraction produced by Coccidioides immitis (strains 634 and 735) grown in culture was isolated. Both this fraction and intact spherules were reactive with sera from coccidioidomycosis patients, as demonstrated by immunofluorescence microscopy. The serological activity of SOW was also demonstrated by its reactivity with human anti-C.

Morphological aspects of gastrointestinal tract invasion by Candida albicans in the infant mouse.

The infant mouse has proved to be a useful model for examination of various aspects of gastrointestinal and systemic candidosis. Oral-intragastric inoculation of 5-6-day-old mice with yeast of a virulent strain of Candida albicans (CA30) resulted in systemic spread within 30 min after challenge. Histological examinations of the gastrointestinal (GI) tract have shown that the highest frequency of invasion of the mucosa by yeast cells occurred in the region of the jejunum 1-3 h after inoculation.