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Biomedical subjects

D Pirozzi

Publications and source records attributed to D Pirozzi.

5 recordsLinked to original sources

Efficient and selective microbial esterification with dry mycelium of Rhizopus oryzae.

The use of dry mycelium of Rhizopus oryzae as biocatalyst for ester production in organic solvent has been studied. Mycelia with notable carboxylesterase activity were produced when different Tweens (20, 40, 60 and 80) were employed as main carbon source for the growth. Dry mycelium of four strains of Rhizopus oryzae proved effective for efficiently catalysing the synthesis of different flavour esters (hexylacetate and butyrate, geranylacetate and butyrate) starting from the corresponding alcohol and free acid, including acetic acid. The esterification of the racemic mixture of 2-octanol and butyric acid proceeded with high enantioselectivity (R-ester produced with enantiomeric excess > or =97%) when Rhizopus oryzae CBS 112.07 and Rhizopus oryzae CBS 260.28 were employed.

Acetates↗

Development of small-size tubular-flow continuous reactors for the analysis of operational stability of enzymes in low-water systems.

A very small-scale continuous flow reactor has been designed for use with enzymes in organic media, particularly for operational stability studies. It is constructed from fairly inexpensive components, and typically uses 5 mg of catalyst and flow rates of 1 to 5 mL/h, so only small quantities of feedstock need to be handled. The design allows control of the thermodynamic water activity of the feed, and works with temperatures up to at least 80 degrees C. The reactor has been operated with both nonpolar (octane) and polar (4-methyl-pentan-2-one) solvents, and with the more viscous solvent-free reactant mixture. It has been applied to studies of the operational stability of lipases from Chromobacterium viscosum (lyophilized powder or polypropylene-adsorbed) and Rhizomucor miehei (Lipozyme) in different experimental conditions. Transesterification of geraniol and ethylcaproate has been adopted as a model transformation.

Acyclic Monoterpenes↗

Dermatologic changes after systemic cancer therapy.

Dermatologic changes associated with systemic cancer therapy are common. These changes can be conveniently grouped into three clinical categories: 1) cytotoxic effects; 2) pigment alterations; and 3) rashes and eruptions. The clinician should be alert to these manifestations so that needless work-up is avoided..

Adult↗

Vasculitis associated with intestinal bypass surgery.

We report two cases in which necrotizing vasculitis with tenosynovitis arthralgia/arthritis syndrome developed after intestinal bypass surgery. Each of these patients had jejunoileostomies, and the excluded segment was placed in an ileal-colonic anastomosis. We speculate that since the attachment of the excluded segment to the large intestine predisposes it to increased bowel overgrowth of bacteria, these bacteria or their debris may have served as antigens for circulating immune complexes, which were detected in both patients by one or more techniques. Patients who have had an end-to-side anastomosis may be less predisposed to the more severe vasculitis syndrome because there is less likelihood of bacterial overgrowth in the bypassed intestinal segment.

Adult↗