Unwashed Products Research Articles

Fine-bubble technology application for pesticide-removal effect in ‘Gros Michel’ banana (Musa acuminata ‘Gros Michel’)

‘Gros Michel’ bananas are among highly exported agricultural product in Thailand. Their cultivation involves several pesticide applications to meet consumer satisfaction. In several countries, pesticide residues found in the bananas may result in rejection and further banned the imported products which may affect export income of Thailand. Therefore, it is important to reduce the level of the pesticide residue to meet Maximum Residue Levels (MRLs). The aim of this study was to investigate the impact of fine-bubble technology on commonly used pesticides, chlorpyrifos and cypermethrin, in banana fruits. The contact times, 15, 30, 60, and 90 minutes, and types of gas, air and ozone, used for microbubble generation were also studied. Pesticide removal effect of fine-bubble technology which was first screened using GPO-TM kits, a test kit for pesticide detection. The findings revealed that both organophosphate and pyrethroid pesticides were not detected after 30 minutes contact time when treated with fine-bubbles regardless of the gas type. Air microbubble treatment was chosen for further quantitative analysis using gas chromatography (GC). In comparison to the unwashed products (Control), air microbubble application lessened chlorpyrifos and cypermethrin by 80% and 72%, respectively. Even though fine-bubble technology successfully reduced pesticide residue in banana fruits, modes of action require further investigation.

Mechanochemical processing of serpentine with ammonium salts under ambient conditions for CO2 mineralization

This paper assesses the suitability of mechanochemistry as a convenient low-energy processing option in CO2 mineralization. Whereas some success has been reported in milling alkaline earth-containing minerals under gaseous CO2, this work focuses instead on a purely solid-state approach towards two key objectives: (a) Mg extraction from serpentine using ammonium bisulfate; and (b) direct or indirect CO2 sequestration using ammonium bicarbonate in a natural extension of its role as “CO2 carrier” in the chilled ammonia scrubbing process. In Mg extraction work, dry milling of serpentine with ammonium bisulfate gave respectable yields (>60% Mg) as boussingaultite [(NH4)2Mg(SO4)2·6H2O] in 2 to 4 h. In CO2 sequestration, dry milling anhydrous magnesium sulfate with ammonium bicarbonate yielded only mixed sulfate products. Carbonation of the heptahydrate, epsomite, was found to proceed via ammonium magnesium carbonate hydrate [(NH4)2Mg(CO3)2·4H2O], which dissolves incongruently to yield nesquehonite [MgCO3·3H2O]. The modest conversion (∼30%) is probably due to equipartition of Mg into the double sulfate co-product. A similar route is followed in magnesia and brucite, in which the existence of an amorphous native carbonate precursor to nesquehonite in the same molar ratio (Mg : CO2 = 1) was inferred from inconsistency in the XRD intensities. This was largely responsible for the high carbonation yields in the unwashed products, ∼70% and ∼85% in MgO and Mg(OH)2, respectively, as confirmed by TG-FTIR. The same intermediate is probably formed in serpentine, but it is apparently soluble in the aqueous mineral environment. When the unwashed product is subjected to mild thermal consolidation, stable hydromagnesite [Mg5(CO3)4(OH)2·4H2O] is formed in ∼20% yield after milling for 16 h. Possible identities for the amorphous precursor are briefly considered.

Mechanism of Alemtuzumab Depletion of T Cells in Stem Cell Products.

Alemtuzumab (a humanized murine monoclonal antibody [MAb] against CD52) is an effective drug for in vitro T cell purging of allogeneic stem cell products when a product is incubated with 10mg of antibody for 30 minutes prior to infusion. Recovery of CD34+ cells has been excellent and T cell purging with alemtuzumab has resulted in a decreased incidence of grade 2–4 GVHD and a reduced incidence of extensive GVHD and a low overall risk of graft failure. However, a higher incidence of cytomegalovirus (CMV) reactivation, respiratory and polyoma virus infections have been observed as has an increased relapse rate in patients with chronic myelogenous leukemia. In vitro purging, using alemtuzumab and infusion of unwashed products, has been associated with a reduced incidence of clinically significant GVHD, an increase in infectious complications and a possible increase in relapse rates. The present studies optimize the purging protocol and examine the mechanism of alemtuzumab purging to identify the role of antibody dependant cell mediated cytotoxicity (ADCC) versus antibody dependant complement mediated cytotoxicity (Ab–C'). Both ADCC and Ab–C' mediated cytotoxicity were active, although ADCC was noticeably more effective. However, cellular viability was improved by incubation with 10% autologous serum. A two hour incubation (1–2×01e8 cells/ml) resulted in a 73% reduction in CD3+ cells, which was increased to 85% after a 16 hour co-incubation. In addition, natural killer (NK) and B cells were purged with alemtuzumab; as were lineage negative (Lin−)-HLA-DR+CD123+ dendritic cells (DCs) but not Lin-HLA-DR+CD11c+ DCs. Immature myeloid suppressor cells (IMSCs), which are Lin−DR−CD33+ or DR−CD14−CD11b+, have a low sensitivity to alemtuzumab cytotoxicity as did hematopoietic progenitor cells (CFU-c function or CD34+ number). This is an exciting observation as IMSCs have the potential to induce T cell tolerance. Optimal T cell purging, with retention of CD34+ hematopoietic stem cell number and activity, requires a 4–6 hr co-incubation of 2×10e8/ml hematopoietic stem cells, 100 ug/ml alemtuzumab in 10% autologous serum at 4C and removal of alemtuzumab by washing in Plasma-Lyte. Co-incubation at 4C and the presence of 10% autologous serum, was required to minimize the toxicity of a 24 hr co-incubation using a high frequency (1–2×10e8/ml) of hematopoietic cells. The selective depletion of T cells, with a retention of IMSCs, suggests that such a purging protocol has potential to not only reduce acute and chronic GVHD but to also induce major histocompatibility complex tolerance. However, our clinical studies need to be completed in order to assess the impact on leukemic relapse.

Preparation of adsorbents from sugarcane manufacturing by-product filter-mud by thermal activation

A series of experiments with thermal activation were carried out on filter-mud waste from the sugarcane refining process in a rotary reactor. The influence of activation parameters on the agro-industrial waste by varying the operation temperature of 600–800 °C was determined. The variations of pore properties as well as the change of chemical characteristics in the resulting solids (FM series) were also studied. The results show that the resulting samples are type IV with hysteresis loops corresponding to type H3 from nitrogen adsorption–desorption isotherms, indicating slit-shaped mesoporous characteristics (BET surface areas of 57–132 m 2 g −1). The results also show that the surface areas of the unwashed products and water-washed products are lower than those of the washed products because of residues left in the crude products. The adsorption of paraquat on FM sample was preliminarily evaluated. The isotherm showed that the FM adsorbent had a high affinity for this herbicide and can be well fitted by Freundlich model. Thus, the agro-industrial waste is one resource for producing the mesoporous materials, and it may be applied to the water treatment for the removal of organic contaminants.

Propensity of Tampons and Barrier Contraceptives to Amplify Staphylococcus aureusToxic Shock Syndrome Toxin‐I

Objective: Although the incidence of reported cases of toxic shock syndrome (TSS) has declined in recent years, the disease continues to occur in menstruating women using the newer, less-absorbent tampons or barrier contraceptives. Extant tampons and other vaginal devices were tested for the ability to induce TSS toxin-1 (TSST-1) by a TSS strain of Staphylococcus aureus MN8, a known high-toxin producer. Tested for the first time were 20 varieties of tampons, including 2 all-cotton brands newly introduced in the United States, a polyurethane contraceptive sponge, a latex diaphragm, and a polymer menstrual collection cup. Methods: All products were washed in sterile distilled water prior to use to reduce the effect of leachable chemicals. Duplicate experiments with unwashed products were also performed. Entire tampons and other test products were immersed in brain heart infusion broth plus yeast extract (BHIY) and inoculated with S. aureus MN8, a known TSST-1 producer. After incubation, the culture supernatants were assayed for TSST-1 by gel immunodiffusion. Results: Except for all-cotton tampons, greater amounts of TSST-1 were detected in the supernatant fluid of washed tampons than detected in those which were not washed. While TSST-1 levels in unwashed non-cotton tampons ranged from 0.5 to 8 μg/ml, when these products were washed, TSST-1 levels increased to 2–32 μg/ml. In all-cotton tampons, whether washed or not, there was no detectable TSST-1. Conclusions: The propensity for all-cotton tampons not to amplify TSST-1 in vitro suggests they would lower the risk for tampon-associated TSS.