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J M Fuentes

Publications and source records attributed to J M Fuentes.

85 records · Page 5Linked to original sources
PubMedDate not supplied

[A polygraphic, haemodynamic and metabolic study of 2 cases of the "locked-in" syndrome (author's transl)].

The sleep-waking pattern, cerebral blood flow (CBF) and cerebral metabolism have been studied in 2 cases of the "locked-in" syndrome, one traumatic, the other vascular in origin. Studies were performed in the third week in the first case and the seventh in the second. A lesion of the ventral pons was suggested clinically and neuroradiologically. The waking EEG was composed of alpha and theta activity. Different stages of slow wave sleep were diminished in quantity (NREM) as was paradoxical sleep (REM). The basal cerebral blood flow (CBF) was increased by 30 p. 100 compared to normals. Cerebral oxygen consumption was normal. The cerebral hyperaemia was evenly distributed and was associated with a failure of autoregulation. The vascular response to CO2 was normal, however. The E.E.G. findings, haemodynamic and metabolic studies confirmed a pontine lesion as the cause of the "locked-in" syndrome in contrast to akinetic mutism where the lesion is in the mid-brain.

Adolescent↗
PubMedDate not supplied

An arginine regulated gamma-guanidobutyrate ureahydrolase from tench liver (Tinca tinca L.).

A gamma-guanidobutyrate ureahydrolase isolated from tench liver has been characterized. Some of its physicochemical properties like pH effect and thermal stability resemble those of arginases, however it shows some peculiarities that makes it different from arginases and other amidino hydrolases. Thus cation requirement is not as strong as in arginases, and the Km value for gamma-guanido-butyric acid (230 +/- 25 mM) is shifted to a lower value (45 +/- 5 mM) by 5 mM arginine. The possible regulatory role of arginine on gamma-guanidobutyrate ureahydrolase activity is discussed.

Animals↗
PubMedDate not supplied

Oscillations in rat liver cytosolic enzyme activities of the urea cycle.

Diurnal rhythms were studied in three rat liver enzymes of the urea cycle: arginase, arginosuccinate synthetase and arginosuccinase. In animals synchronized to a 12:12 h light-dark cycle these enzymes were determined at 8 different time points under three different feeding schedules: 24 h of fasting, ad libitum feeding and restricted feeding. Under the three experimental conditions maxima of enzyme activities occurred during the dark period. In all cases the maximum activity of arginosuccinase preceded the one of arginase and these in turn the one of arginosuccinate synthetase. On the other hand, the hepatic protein level was maximal during the light period and decreased to its lowest level during the dark period. The restriction of food between 08.00 h and 14.00 h induced an important phase shift of hepatic protein rhythm and arginosuccinase activity. Our results suggest that the diurnal rhythms of cytosolic enzymes of the urea cycle are not only dependent on the light-dark cycle, but also on the synchronizing and masking effect of food intake.

Animals↗
PubMedDate not supplied

Kinetics and inhibition by some aminoacids of lactating rat mammary gland arginase.

Some kinetic and regulatory properties of lactating rat mammary gland arginase were studied. At pH 7.4, i.e. at near-physiological conditions, there was evidence of inhibition by excess of substrate, with a Km value of 9.5 mM, slightly lower than the value of 18 mM observed at pH 9.8 (maximum enzyme activity). A study was also made of the effects of proline, ornithine, lysine and certain branched-chain aminoacids on enzyme activity: lactating rat mammary gland arginase was strongly and competitively inhibited by lysine, ornithine and valine, with Ki values of 1.2 mM, 1.1 mM and 3.6 mM, respectively. Other aminoacids (proline, isoleucine and leucine) also inhibited lactating rat mammary gland arginase, although to a lesser extent.

Amino Acids↗
PubMedDate not supplied

[Complementary procedures to the Sjoqvist operation in cancerous cervico-facial pain].

The trigeminal spinal tractotomy of Sjoqvist can be enlarged and give a very good result on cancer pain of face and throat. When pain is also cervical, it is usefull to associate with the Sjoqvist operation two important procedures: 1 degree--Instead of a simple posterior cervical radicotomy it seems best to practise a selective posterior radicellotomy. This technic has the advantage to preserve the sensory proprioceptive capacity of the superior limb, while being perform even until C6 and C7 roots. Also in case of recurrence of cervico brachial pain, it remains easy to apply a posterior spinal stimulation. 2--The spinal nerve has not only a motor function but also a sensory one. The sensory fibers travelling through small anastomosis between "LARUELLE Ganglion" and cervical roots must be separated to obtain a more complete analgesia.

Facial Neuralgia↗
PubMedDate not supplied

[Results of selective posterior radiculetomy at the lumbar and cervical level].

At the light of authors' present experience, radicletomy appears as an excellent antalgic operative procedure in the case of roots with high functional risk (brachial plexus and lumbar plexus). In the absence of any motor deficiency or ataxia, it appears that radicletomy is of help in the cure of severe hypertonies of the extremities (sequelae of cerebral stem contusions). Conversely, in the spastic sequelae of hemi- or paraparesias, lumbar-sacral posterior selective radicotomy is a sure procedure that procures results nearly super-imposable to radicletomy with an appreciable gain in time. At last, for what concerns the motor involvements of the upper extremity ending in spasticity, selective radicletomy recovers its rights and has to be preferred to S.P.R. The indications may be summarized as follows: -- At the level of the lower extremities: in the case of paraparetic sequelae or of sequelae due to spastic paraplegia, a S.P.R. has to be performed; for what concerns antalgic surgery, in the absence of motor deficiency, the best indication is radicletomy. -- At the level of the upper extremities: in the case of dystonic sequeale of the cerebral stem, spastic pain bound with hemiplegia or with carcinoma etc. (herpes zoster..), radicletomy constitutes the ideal surgical procedure.

Adult↗
PubMedDate not supplied

["Run-off" bypass].

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Aged↗