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J C Alvarez

Publications and source records attributed to J C Alvarez.

58 records · Page 4Linked to original sources
PubMedDate not supplied

[Neuroanatomy of the nuclear vestibular complex in the syrian hamster. Comparison with other mammals].

The vestibular complex has been studied since the fifties. The general conclusion of research on many mammals is that the vestibular complex has four main vestibular nuclei and some less constantly associated neuronal groups. The general distribution of the four main vestibular nuclei in the hamster does not differ substantially from that of other mammals: humans, many primates, cat, opossom, rabbit, chinchilla, guinea pig, etc. Of the many associated groups that have been described, we clearly identified groups < >, < >, < >, < >, and the interstitial nucleus of the vestibular nucleus of Cajal. However, the latter seems to be less developed than in other mammals. We present results and a map of serial sections of the vestibular area showing the most characteristic anatomic relations with brainstem structures, and the most relevant cytomorphometric results compared with other mammals.

Animals↗
PubMedDate not supplied

[Core and cutaneous thermal changes in the upper limb after anesthesia induction].

OBJECTIVES: To describe and compare the core-cutaneous thermal and photoplethysmographic time-course effects after induction of general anesthesia with propofol, fentanyl and vecuronium. PATIENTS AND METHODS: We measured digital blood flow, core temperature and skin temperature in the upper limb (fingertip, forearm and upper arm) in 20 patients (10 men and 10 women, ASA-I) before anesthetic induction and 5, 10, 15 and 20 min after induction. Skin temperature changes were recorded with disposable thermocouples. Blood flow was recorded by digital photoplethysmography (PhPl) in the thumb. Anesthesia was provided without premedication, using propofol (3 mg.kg-1), fentanyl (0.1 mg) and vecuronium (0.1 mg.kg-1). After endotracheal intubation, anesthesia was maintained with oxygen-nitrous oxide and 0.1 mg of intravenous fentanyl at the tenth minute, without inhaled anesthetics. RESULTS: All patients showed intense, abrupt vasodilatation in the thumb with marked increases in PhPl (PhPl = 10.4 +/- 5.0 mV/V, at 5 min, p < 0.001) and fingertip temperature (TFingertip = 6.2 +/- 2.0 C, at 10 min, p < 0.001). However, skin temperature changes in the upper arm and forearm were moderate and slower (TForearm = 2.1 +/- 1.4 C, p < 0.01 and TUpper arm = 1.1 +/- 1.2 C, p < 0.01; at 20 min in both cases). A significant correlation was found only between PhPl and TFingertip (r = 0.55, p < 0.001). CONCLUSIONS: Anesthetic induction with propofol, fentanyl and vecuronium produces cutaneous vasodilatation in the upper limb unequally: the greatest increase in skin temperature occurs at the fingertip, while forearm and upper arm temperatures increase less. We think that skin vasodilatation in peripheral distal areas may play an important role in redistributing core heat during anesthesia.

Anesthesia, Intravenous↗
PubMedDate not supplied

[Carotid thrombosis as the clinical onset of cervical metastasis of unknown origin].

Carotid infiltration by a cervical metastatic node, although uncommon, has a poor prognosis and controversial treatment. We report the case of a 59-year-old male patient with a metastatic node of squamous cell carcinoma of unknown origin and a clinical onset in the form of ischemic cerebrovascular accident caused by ipsilateral occlusion of the internal carotid. Radical neck dissection was performed, sparing the carotid artery, which was not infiltrated by the tumor. The pathogenesis of carotid occlusion is discussed and the literature reviewed.

Carcinoma, Squamous Cell↗