Adventitious shoot regeneration in peach [<Emphasis Type="Italic">Prunus persica</Emphasis> (L.) Batsch]

A method for adventitious shoot regeneration from leaves of micropropagated peach shoots has been developed. Apices were excised from in vitro shoot cultures of a seed-derived (juvenile) genotype (P16Cl5) and mature genotypes (Babygold 6, 842 Standard, San Giorgio and Yumyeong). Apices were cultured 21 days in the dark on a medium supplemented with 6-benzyladenine and α-naphthaleneacetic acid and then transferred to an auxin-free medium and incubated in the light for 21 days. The first four apical leaves were excised from these apices and cultured in the same way. During the dark incubation period, leaves developed a callus at the petiolar base. Adventitious shoots appeared on this callus after transfer to auxin-free medium and culture under light conditions. The morphogenic ability of the callus was maintained for several months.     

Different efficacy of iodoacetic acid and N-ethylmaleimide in high-performance liquid chromatographic measurement of liver glutathione

The widely used high-performance liquid chromatography (HPLC) procedure to determine glutathione in biological samples utilizing iodoacetic acid as thiol quenching agent and 1-fluoro-2,4-dinitrobenzene for derivatization has been modified regarding tissue sample processing and storage of the working solutions. The modified procedure compared with the original method reduces artifactual oxidation in rat liver glutathione measurement (1.47±0.8% vs. 2.84±0.69%, respectively). In both HPLC procedures, an increase in artifactual oxidation was found in both standard glutathione solutions and hepatic samples when N-ethylmaleimide instead of iodoacetic acid was used for thiol trapping.     

The Importance of a Proper Aetiological Diagnosis in the Management of Patients with Invasive Mycoses: A Case Report of a Brain Abscess by <Emphasis Type="Italic">Scedosporium apiospermum</Emphasis>

Scedosporium apiospermum is a saprobic fungus responsible for many different clinical manifestations. Although it affects mostly immunocompromised patients, pulmonary and disseminated scedosporiosis have also been reported in immunocompetent subjects. It often causes subcutaneous mycetoma, despite its preferential tropism to CNS. The authors describe a fatal case of a S. apiospermum brain abscess in a 58-year-old female. She was affected by chronic liver disease and idiopathic pulmonary fibrosis and had been treated with corticosteroid therapy for a long time. She recovered in a neurosurgery unit, wherein TC scan and cerebral MRI revealed an expansive left temporo-parietal process with vasogenic oedema. A stereotactic puncture of the lesion was carried out, and pus of brain abscess was evacuated. Empirical antifungal therapy was initiated with liposomal amphotericine B based on the clinical suspicion of Zygomycetes infection; after 3 days, posaconazole was added. The correct aetiological diagnosis arrived too late and the patient was treated with no specific therapy. This fatal case confirms the necessity of having a fast and correct aetiological diagnosis to improve the patient’s outcome.     

Functional Near Infrared Spectroscopy of the Sensory and Motor Brain Regions with Simultaneous Kinematic and EMG Monitoring During Motor Tasks

There are several advantages that functional near-infrared spectroscopy (fNIRS) presents in the study of the neural control of human movement. It is relatively flexible with respect to participant positioning and allows for some head movements during tasks. Additionally, it is inexpensive, light weight, and portable, with very few contraindications to its use. This presents a unique opportunity to study functional brain activity during motor tasks in individuals who are typically developing, as well as those with movement disorders, such as cerebral palsy. An additional consideration when studying movement disorders, however, is the quality of actual movements performed and the potential for additional, unintended movements. Therefore, concurrent monitoring of both blood flow changes in the brain and actual movements of the body during testing is required for appropriate interpretation of fNIRS results. Here, we show a protocol for the combination of fNIRS with muscle and kinematic monitoring during motor tasks. We explore gait, a unilateral multi-joint movement (cycling), and two unilateral single-joint movements (isolated ankle dorsiflexion, and isolated hand squeezing). The techniques presented can be useful in studying both typical and atypical motor control, and can be modified to investigate a broad range of tasks and scientific questions.     

Novel use of a perfluorocarbon for supplying oxygen to aerobic submerged cultures

Summary A novel method for supplying oxygen by using a perfluorocarbon as an oxygen carrier in submerged cultures was demonstrated. Oxygen was transferred to the aqueous phase by liquid-liquid contacting in a spray column fermentor. Advantages of using such a system for supplying oxygen are discussed.Nomenclature F₁ recirculation rate of PP9 through nozzle - P_B back pressure at nozzle - SA_PP9 oxygen concentration in PP9 in aerator as a percent of saturation when air equilibrated at the end of the exponential phase of growth - T_F fermentation time to reach final cell concentration - V_A air flow rate through sparger - X_e cell concentration at the end of the exponential phase of growth - X_F final cell concentration - Ø_A gas (air) hold-up - Ø_L liquid (PP9) hold-up in aqueous system     

The effects of nonvolatile toxic substances on the yeast growth during ethyl alcohol fermentations

Summary Nonvolatile toxins accumulated during alcohol fermentation reduce the yeast growth rate, but not the maximum cell concentration. Specific growth rates decline exponentially according to the increase in toxins. The accumulation of salts and proteins seem to be responsible for the inhibition.To whom all correspondence should be addressed.     

Continuous ethanol fermentation ofZymomonas mobilis using soy flour as a protective agent

Biotechnology Letters - From the analysis of steady state data, an increase of 81.6% in ethanol concentration and fermentor productivity was obtained due to the addition of soy flour to a...     

Isolation and characterization of a serine esterase from cytolytic T cell granules

Cytotoxic T lymphocytes and lymphocytes with NK-like activity contain a serine esterase activity which has been localized to their cytoplasmic granules by cytochemistry and subcellular fractionation studies. The serine esterase-specific inhibitor 3H-DFP labels two protein species in the granules. The two proteins, referred to as serine esterases 1 and 2 (SE 1 and SE 2), migrate with Mr of 34-36 kd and 28-30 kd, respectively, under reducing conditions. SE 1 shows trypsin-like activity and has been purified to apparent homogeneity. Under nonreducing conditions, SE 1 has an Mr of 60-66 kd, suggesting that it may consist of two disulfide-linked subunits of 34-36 kd each. SE 1 cleaves fibrin and casein, has a pl greater than 10, and optimal activity at pH 8. The substrate specificity of SE 2 is not known. The serine esterase activity is secreted by lymphocytes that have been stimulated with the calcium ionophore A23187. The serine esterases described here could play an active role in cell-mediated killing.     

Oxidative stress induces increase in intracellular amyloid beta-protein production and selective activation of betaI and betaII PKCs in NT2 cells

Amyloid beta-protein (Abeta) aggregation produces an oxidative stress in neuronal cells that, in turn, may induce an amyloidogenic shift of neuronal metabolism. To investigate this hypothesis, we analyzed intra- and extracellular Abeta content in NT2 differentiated cells incubated with 4-hydroxy-2,3-nonenal (HNE), a major product of lipid peroxidation. In parallel, we evaluated protein kinase C (PKC) isoenzymes activity, a signaling system suspected to modulate amyloid precursor protein (APP) processing. Low HNE concentrations (0.1-1 microM) induced a 2-6 fold increase of intracellular Abeta production that was concomitant with selective activation of betaI and betaII PKC isoforms, without affecting either cell viability or APP full-length expression. Selective activation of the same PKC isoforms was observed following NT2 differentiation. Our findings suggest that PKC beta isoenzymes are part of cellular mechanisms that regulate production of the intracellular Abeta pool. Moreover, they indicate that lipid peroxidation fosters intracellular Abeta accumulation, creating a vicious neurodegenerative loop.