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C Migliorini

Publications and source records attributed to C Migliorini.

3 recordsLinked to original sources

p53 tumour suppressor gene and RAS oncogenes: molecular analysis in the chronic and leukaemic phases of essential thrombocythaemia.

A panel of 51 cases of essential thrombocythaemia (ET), in chronic or leukaemic phase, was investigated for p53 gene and RAS oncogenes mutations by PCR-SSCP-direct sequencing. No RAS oncogenes mutations were detected, but p53 mutations were identified in three cases: 1/27 cases (approximately 4%) in chronic phase not undergoing chemotherapy, 1/19 cases (approximately 5%) in chronic phase undergoing chemotherapy, and 1/5 cases (20%) which had progressed to leukaemia. Our results suggest that: (1) p53 gene mutations occur sporadically in the chronic phase of ET, independent of chemotherapy, and may contribute to the progression to the leukaemic phase in a limited number of ET patients; (2) the RAS genes family does not seem to be involved in the pathogenesis of ET, unlike other bcr/abl negative chronic myeloproliferative diseases (CMPDs).

Adult↗

Anatomical organization of the spinal paths to the soleus and gastrocnemius muscles of the rat hind limb.

The anatomical organization of the motoneuronal columns of the soleus and lateral gastrocnemius muscle and of the related premotor interneurons was studied in rats, using the retrograde transneuronal transport of WGA-HRP. Motoneurons of the gastrocnemius muscle have a well-developed dendritic arborization which spreads into the transverse plane of the spinal cord extending to the intermediate region of the grey matter, while dendrites of the soleus muscle motoneurons spread mainly in the rosto-caudal plane, where they remain inside the border of the motoneuronal column and form small dendritic bundles, suggesting a coupling of neuronal activity as is to be expected in the motoneurons of a tonically active postural muscle such as the soleus. Gastrocnemial premotor interneurons are located close to the motoneuronal column, while the soleus premotor interneurons are scattered all over the ventral horn and intermediate grey. The number of labelled premotor interneurons is greater when the WGA-HRP is injected into the soleus muscle. In both cases, the premotor interneurons could be classified as four different types on the basis of the shape and size of the neuronal somata. The differences in the anatomical organization of the spinal paths to the gastrocnemius and soleus muscles reflect the different tasks performed by these two synergic muscles in normal motor behaviour: fast phasic activity by the gastrocnemius muscle, slow tonic anti-gravity activity by the soleus muscle.

Animals↗

Regioselective enzymatic diol esterification in batch and fixed-Bed adsorptive reactors: experiments and modeling.

The dynamic behavior of batch and fixed-bed adsorptive reactors is studied for the enzyme-catalyzed regioselective esterification of propionic acid and 2-ethyl-1,3-hexanediol in hexane. The reaction is equilibrium-limited with an apparent equilibrium constant of 0.6 +/- 0.1 at 22 degrees C. Moreover, accumulation of water produced in the reaction onto the biocatalyst causes a decrease in the catalytic activity. As a result, improvements in both reaction rate and final conversion can be achieved by operating in an adsorptive-reactor mode. Control of water in the reactor is achieved with a catalytically inert ion-exchange resin in Na-form. The resin prevents an excessive accumulation of water on the biocatalyst and reduces equilibrium limitations. The thermodynamic activity of water is identified as a key parameter for the design of such reactors. A mathematical model capable of predicting the water activity as a function of the varying concentrations of reactants and products is thus developed and found to successfully predict the experimental behavior observed in laboratory reactors. Substantial improvements in performance predicted by the model are seen experimentally in batch reactions and during the transient operation of continuous-flow fixed-bed reactors combining adsorptive and catalytic functions.

Adsorption↗