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Biomedical subjects

J Cano

Publications and source records attributed to J Cano.

175 records · Page 10Linked to original sources
PubMed1981

Myelin-like inclusions in maturing and senescent muscle cells of rat myocardium.

This paper deals with the ultrastructure of two types of cytoplasmic inclusions, "myelin figures" and "lipid complexes", present in muscle cells of ventricular myocardium of the rat heart. The inclusions were numerous in both the first two postnatal weeks and in the senescent stages, being rarely observed in young adult animals. The myelin figures were entirely made up of myelin-like membrane whorls, whereas the lipid complexes exhibited discrete myeloid caps surrounding a central lipid core. The origin and functional significance of such myelin-like structures are discussed on the basis of ultrastructural and biochemical studies on myocardial physiology and age-related evolution.

Aging↗
PubMed1981

Comparison between developmental and senescent changes in enzyme activities linked to energy metabolism in rat heart.

The developmental and senescent patterns of a number of heart enzyme activities linked to energy metabolism have been studied in rats aged between 4 days and 21 months. A morphometric study of mitochondrial volume fractions and numbers has been also carried out. Developmental changes result in a rise of most mitochondrial enzymes (NADP+-isocitrate dehydrogenase, malic enzyme, succinate dehydrogenase, citrate synthase) and mitochondrial volume fractions. Exceptions are NAD+-isocitrate dehydrogenase, which declines from 4 days onwards, and NAD+-malate dehydrogenase, which declines and then rises over the same period. Senescent changes follow two different trends. While pyruvate kinase and those mitochondrial enzymes lying between citrate formation and isocitrate oxidation (citrate synthase, NADP+-and NAD+-isocitrate dehydrogenases) decline to some degree, mitochondrial succinate dehydrogenase and NAD+-malate dehydrogenase activities increase over the same period. This could point towards a partial impairment of Krebs cycle function, and a reduced energy-producing capacity in the aged rat heart.

Aging↗
PubMed1980

Effect of cerebellar lesions on monoamine levels in various brain areas of the cat.

Modifications in thee content of monoamines after different lesions of the cerebellar cortex were investigated in eight prosencephalic structures of cat's brain. Apart from other minor changes, lesions of the posterior vermis induced significant changes in the thalamus (decrease of DA and increase of 5-HT). Lesions of the cortex of a cerebellar hemisphere, on the other hand, produced an increase of 5-HT in the caudate nucleus and an increase of DA in the hippocampus in addition to a generalized increase of 5-HT in all the prosencephalic structures studied. These findings are discussed in relation to the anatomical connections of the lesioned areas and their expected role in the sleep-wakefulness cycle.

Animals↗
PubMed1980

Degenerating taste buds in sialectomized rats.

In the present report changes are described in degenerating taste buds (TB) from rats deprived of the main salivary glands (parotid, sublingual and submaxillary glands). These changes include macrophages located inside the degenerating TB cell, lipid droplets and a heterogeneous population of digestive vacuoles. In addition, a large number of bacteria was found to permeate the apical taste pore. It is of interest that normal nerve fibers were seen synapsing with the degenerating TB cells. The sialectomy-induced degeneration of TB would not be, therefore, a consequence of neural deprivation.

Animals↗
PubMed1978

[Modulating effect of the salivary glands upon differentiation and maturation of taste bud cells in the rat (author's transl)].

It is currently considered that the sensitive nerves of the papillary plexus are solely responsible for the normal differentiation of taste bud cells in the circumvallate papillae of the rat. The effect of syallectomy on taste bud cells was studied. Evaluation of results was performed through cell counts. The results demonstrate that the major salivary glands are quite important in both differentiation and maturation of taste bud cells.

Cell Count↗
PubMedDate not supplied

The influence of age on neurotransmitter turnover in the rat's superior colliculus.

Measurements of the turnover of dopamine, noradrenaline and serotonin and their metabolites have been performed in the superior colliculus of adult and aged rats. The turnover of dopamine, noradrenaline and their metabolites after pargyline treatment was significantly lower in aged rats than in adults. On the contrary, the synthesis rate of serotonin (measured by accumulation of 5-hydroxytryptophan after decarboxylase blockade) and the turnover rate of serotonin (after pargyline treatment) did not change during aging. These findings suggest that aging has a different effect on catecholamines and serotonin turnover in the superior colliculus of the aged rats.

3,4-Dihydroxyphenylacetic Acid↗
PubMedDate not supplied

Countercomplementarity and strong ferromagnetic coupling in a linear mixed mu-acetato, mu-hydroxo trinuclear copper(II) complex. Synthesis, structure, magnetic properties, EPR, and theoretical studies.

The structural and magnetic data of the trinuclear compound [Cu3(L)2(CH3COO)2(OH)2(dmf)2] (HL = N-(2-methylpyridyl)toluensulfonylamide) are reported. The compound crystallizes in the monoclinic system, space group P2(1)/n (no. 14), with a = 11.6482(6) A, b = 13.5772(6) A, c = 13.5306(7) A, alpha = 90 degrees, beta = 92.859(5) degrees, gamma = 90 degrees, and Z = 2. The three copper atoms form an exact linear arrangement. Neighboring coppers are connected by a hydroxo bridge and a bidentate syn-syn carboxylato group. The coordination spheres of the terminal copper atoms are square pyramidal with a dmf molecule as the apical ligand. The central copper has a regular square planar geometry. The mixed bridging by a hydroxide oxygen atom and a bidentate carboxylato group leads to a noncoplanarity of the adjacent basal coordination planes with a dihedral angle of 51.96(9) degrees. Susceptibility measurements (2-300 K) reveal a strong ferromagnetic coupling, J = 93(6) cm-1, in the mixed-bridged moiety leading to a quartet ground state that is confirmed by the EPR spectra. The ferromagnetic exchange coupling is discussed using DFT calculations on model compounds that have shown a countercomplementary effect of the hydroxo and acetate bridges.

Journal Article↗
PubMedDate not supplied

Study of the invasion of human hair in vitro by Aphanoascus spp.

The course of the destruction of human hair in vitro by three species of the genus Aphanoascus (A. keratinophilus, A. fulvescens and A. verrucosus) was studied with light microscopy, and transmission and scanning electron microscopy. The results obtained show that all the three species develop keratinolytic activity. A. fulvescens and A. verrucosus have similar sequences of degradation, invading the hair through the cuticula, but without the presence of specialized erosive organs. A. keratinophilus, however, shows a different way of invasion, and the keratinolytic activity was mainly located in the cortex and from that point on expanded to the cuticula.

Ascomycota↗
PubMedDate not supplied

[Use of cryotherapy in the Rochapea Health Centre].

An analysis is made of the results obtained with the application of cryotherapy to 128 lesions: 86 common warts and 42 flat papillomas, of the 203 diagnosed in the Rochapea Health Centre in the period between October 1996 and June 30th 1997. 55.28% corresponded to warts located on the upper extremities, 34.78% were located on the head and neck, 8.07% on the lower extremities and 1.24% on the thorax. The percentage of flat papillomas was 20.68%. 2.96 sessions were needed to cure each lesion, with an average length of treatment of 42 days. No cases of postcryotherapy infection were registered and there was only one retarded complication, which was the appearance of a keloid scar. We conclude from the present study that cryotherapy is a good treatment for common warts and flat papillomas.

English Abstract↗
PubMedDate not supplied

[Primary orthostatic tremor: slow harmonic component as responsible of inestability].

BACKGROUND: Orthostatic tremor (OT) is clinically defined as a tremor of the lower limbs and trunk on walking. It bears a significant functional impairement. Although the term orthostatic tremor was first used by Heilman in 1984, Pazzaglia et al had previously described some cases in 1970. Despite the fact that the pathophysiology of this entity is not fully known, the presence of a central oscillator is generally accepted as being responsible. A high frecuency tremor, between 13 and 18 Hz, constitutes an almost patognomonic finding, and treatment with clonazepam usually improves the symptoms. PATIENT AND METHOD: We present a patient who described his symptoms as "cramps" in lower limbs and trunk on standing up, which were relieved on walking or resting. RESULT: This clinical presentation together with a neurophysiological recording of the tremor showing an activity of lower frequency (8 Hz) combined with the usual higher frequency (16 Hz) and above all the clear amelioration of symptoms when treated with gabapentin, i.e. resolution of the low frequency tremor without changes in the 16 Hz tremor, were the peculiar features of this case which merits discussion. CONCLUSIONS: The slow component of the orthostatic tremor is crucial in this case. The improvement with gabapentin is explained by the disappearance of this slow c

Acetates↗
PubMedDate not supplied

[Erythrocytic enzymatic systems and their antioxidative potential in pregnant women undergoing labor induction with intracervical PGE2].

Our purpose is to correlate, the apgar score of the new-borns from induction of labour (IL) with Prostaglandin E2 (PGE2) endocervical gel, and the oxidative environment of the pregnant woman during labour, studying biochemical markers of the erythrocytes. PGE2 is responsible for the regulation of the vascular response in pregnancy, namely for the vasoconstriction caused by Angitensin II. The production of Prostaglandins in vivo depends on mechanisms related to free radicals of oxygen (FRO). The production of FRO is enhanced in normal pregnancy. We have studied two erythrocytic enzymes and plasmatic concentration of PGE2 before and after the IL. Those enzymes are oxireductases-the transmembrane reductase (RTM) and the metahemoglobin reductase (MHR). Their function is to prevent the effects of the FRO on cellular biomolecules namely the endothelium and the red blood cells. This prevention of oxidative stress can facilitate the deformability of the erythrocytes, so these cells can easily transpose the small vessels and bind the oxygen to the tissues. The activity of those enzymes can be modulated by PGE2 used in the IL. We have not found significant variations on the activity of RTM after IL. The activity of MHR was enhanced with statistical significance, 30 minutes after the induction. This enhancement of activity can be a mechanism to prevent the oxidative stress of the induction of labour.

Adult↗