Combined yeast and microalgal cultivation in a pilot-scale raceway pond for urban wastewater treatment and potential biodiesel production.

A mixed culture of oleaginous yeast Lipomyces starkeyi and wastewater native microalgae (mostly Scenedesmus sp. and Chlorella sp.) was performed to enhance lipid and biomass production from urban wastewaters. A 400 L raceway pond, operating outdoors, was designed and used for biomass cultivation. Microalgae and yeast were inoculated into the cultivation pond with a 2:1 inoculum ratio. Their concentrations were monitored for 14 continuous days of batch cultivation. Microalgal growth presented a 3-day initial lag-phase, while yeast growth occurred in the first few days. Yeast activity during the microalgal lag-phase enhanced microalgal biomass productivity, corresponding to 31.4 mgTSS m-2 d-1. Yeast growth was limited by low concentrations in wastewater of easily assimilated organic substrates. Organic carbon was absorbed in the first 3 days with a 3.7 mgC L-1 d-1 removal rate. Complete nutrient removal occurred during microalgal linear growth with 2.9 mgN L-1 d-1 and 0.96 mgP L-1 d-1 removal rates. Microalgal photosynthetic activity induced high pH and dissolved oxygen values resulted in natural bactericidal and antifungal activity. A 15% lipid/dry weight was measured at the end of the cultivation time. Fatty acid methyl ester (FAME) analysis indicated that the lipids were mainly composed of arachidic acid.

Organic and conventional fertilisation procedures on the nitrate, antioxidants and pesticide content in parts of vegetables.

Different parts of plant foods are generally discarded by consumers such as peel, stalk and leaves, which could however possess a nutritional value. However, few studies have analysed the composition of these marginal foods. The phenolic compound, flavonoid, polyamine, nitrate and pesticide contents of parts of vegetables that are usually discarded--but which were cultivated according to conventional and non-conventional procedures--were analysed to provide suggestions on how to improve the consumption of these parts and to reduce the production of urban solid waste. Few, but significant, differences between the two manuring procedures were observed. Higher nitrate content and the presence of organochlorine pesticides were found in conventional cultivated papaya peel, lemon balm leaves, jack fruit pulp, and beet stalk and peel. Discarded parts of plant foods such as stalk, leaves and peels can be used as a source of antioxidant compounds, such as phenolic compounds.

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.

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.

Solid-state enzyme deactivation in air and in organic solvents.

Thermal deactivation of solid-state acid phosphates (E.C. 3.1.3.2, from potato) is analyzed, both in the presence and in the absence of organic solvents. The thermal deactivation profile departs from first order kinetics and shows an unusual activity. The process is described by a phenomenological equation, whose theoretical implications are also discussed. The total amount of buffer salts in the enzyme powder dramatically affects enzyme stability in the range 70 degrees C to 105 degrees C. The higher salt/protein ratio increases the rate of thermal deactivation. The deactivation rate is virtually unaffected by the presence of organic solvents, independent of their hydrophilicity.

The effect of sorbitol on acid phosphatase deactivation.

Acid phosphatase thermal deactivation follows a complex path: an initial decay toward an equilibrium distribution of at least two intermediate structures, mutually at the equilibrium, followed by a final breakdown toward a completely inactive enzyme configuration. The results obtained in the presence of sorbitol have been compared to those produced in the course of purely thermal deactivation of the native enzyme. For any sobitol concentration, an equivalent temperature is calculated that results in exactly the same activity-versus-time profile. This suggests enzyme deactivation to be controlled by a single, unchanging step. Immobilized enzyme runs have been performed, as well, by entrapping acid phosphates within a polymeric network formed onto the upstream surface of an ultrafiltration membrane. The stabilizing effect of entrapment cumulates with that produced by sorbitol. In this case, however, an equivalent temperature cannot be determined, thus indicating that a different deactivation mechanism is followed.

Evaluation of a new halcinonide formulation in the treatment of common dermatoses.

An open evaluation of halcinonide 0.1 percent in a hydrophilic vanishing cream base was conducted in one hundred patients with common steroid-responsive dermatoses, including eczema, contact dermatitis, atopic dermatitis stasis dermatitis, and neurodermatitis. Patients applied the cream two or three times a day for two weeks (or less if the clinical response warranted earlier discontinuation). Follow-up assessments were made on days 4, 7, and 14 of the study. Ninety-eight percent of the patients showed some degree of improvement, and eighty-five percent had complete clearing or marked improvement. One patient had no response and one worsened. Seventy-seven percent of the patients who responded achieved their maximum response within the first week of treatment. One case of urticaria was the only side effect noted in this series. Ninety-six percent of the patients rated their acceptance of the new formulation as excellent or good.

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..

Extensive cutaneous metastases from urinary bladder carcinoma.

Herein we present an update of the literature and a report of a recent case of cutaneous metastases from transitional cell carcinoma of the urinary bladder. Cutaneous metastases from bladder carcinoma more commonly affect middle-aged or elderly men and generally herald a rapid demise. Our case is unusual because of the rather extensive area of skin involvement, rapidity of development, and occurrence in a woman.

Drug-induced toxic epidermal necrolysis in children. Report of two cases.

Two cases of toxic epidermal necrolysis occurring in children are presented herein. In both, multiple drugs were administered before the onset of the skin eruption. Cultures for staphylococcus were negative. Histopathologic examination of the first case revealed separations at the dermal-epidermal junction. While more commonly due to staphylococcal exfoliatoxin, a drug must be ruled out as the cause of toxic epidermal necrolysis in children.

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.

An unusual case of North American blastomycosis.

A patient with a laryngeal tumor first diagnosed as squamous cell carcinoma was subsequently found to have North American blastomycosis. Diagnosis of this condition eventuated in eradication of the lesion as well as removal of a tracheostomy, which was thought to be permanent.

Skin capillary changes in early systemic scleroderma. Electron microscopy and "in vitro" autoradiography with tritiated thymidine.

Skin biopsy specimens obtained from involved and noninvolved areas in a patient with early diffuse systemic scleroderma were processed for histology, electron microscopy, and "in vitro" autoradiography with tritiated thymidine. The affected area revealed cellular infiltrates around the eccrine sweat glands, consisting of plasma cells and lymphocytes. The capillaries showed thickening of the basement lamina, damage of endothelial cells, and obstruction of their lumens. However, in some vessels, endothelial cells were preserved and appeared in prophase. Autoradiography with tritiated thymidine showed a marked increase in endothelial and periendothelial cell labeling. Blood immunological studies revealed an increase in B-lymphocytes, IgG, and IgA and the presence of antinuclear and antismooth muscle antibodies.

Disseminated superficial actinic porokeratosis. Analysis of an affected family.

A family is analysed in which disseminated superficial actinic porokeratosis (DSAP) occurred in five members. All three children of one generation are affected. Clinical, histopathological and genetic aspects of DSAP are discussed. Disseminated superficial actinic porokeratosis appears to be a clinical variant of porokeratosis of Mibelli. Since DSAP is a genodermatosis inherited as an autosomal dominant it can occur in any geographical location; however excess sunlight can definitely exacerbate the condition.