[Skin and soft tissue infections in children: consensus on diagnosis and treatment].

Skin and soft tissue infections are a common reason for consultation in primary health care centers. Data from the local epidemiology of these infections are rare, but Staphylococcus aureus and Streptococcus pyogenes are known to be the major etiologic agents. The appearance in recent years of community-originated strains of methicillin-resistant S.

Human Brucella canis outbreak linked to infection in dogs.

The zoonotic risk of Brucella canis has been considered fairly high for persons who handle breeding dogs in kennels or are exposed to infected animals. Transmission to humans in other circumstances has been thought to be rare. We describe an uncommon outbreak of brucellosis caused by B.

[Multicenter study on the prevention of congenital toxoplasmosis in Buenos Aires].

Toxoplasmosis is an infection caused by Toxoplasma gondii, an intracellular parasite of universal distribution, with a variable prevalence depending on the region. This infection causes both morbidity and mortality in the fetus and newborn. The present study is an evaluation of the Argentine Consensus Guidelines regarding prenatal prevention of toxoplasmosis.

[Argentine Consensus of Congenital Toxoplasmosis].

The mother-to-child transmission in Toxoplasma gondii infection occurs only when the infection is acquired for the first time during pregnancy. The prenatal and early postnatal diagnosis can only be achieved by serological testing. Serologic tests have different sensitivities, specificities and complexities, so that different tests in more than one blood sample are necessary for the diagnosis.

[Community-acquired methicillin-resistant Staphylococcus aureus infections in a hospital for acute diseases].

Community-acquired methicillin-resistant Staphylococcus aureus infections in a hospital for acute diseases. Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most prevalent pathogens associated with nosocomial infections. However, most recently, MRSA has arisen as an emerging community pathogen, causing serious infections, mainly among young patients.

Saccadic eye movements are impaired in Duchenne muscular dystrophy.

Extraocular muscles are generally considered to be spared in Duchenne Muscular Dystrophy (DMD). However, this assumption is based mainly on clinical observations, as systematic eye movement recordings have been performed in a very limited number of cases. Our goal was to analyze several saccade parameters in a higher number of cases, in order to reveal a possible ocular-motor impairment in DMD.

Bilateral representation of sequential finger movements in human cortical areas.

The spatial distribution of cortical neural clusters activated during movement of either hand ('bilateral' population), or only of one hand, was investigated in healthy right-handed volunteers performing a sequential finger opposition task, using echo-planar functional magnetic resonance imaging. 'Bilateral' clusters were found in the mesial premotor, perirolandic and adjacent lateral premotor cortex of the two hemispheres, and in the left superior parietal lobule. In the precentral gyrus, their spatial extent was larger on the left hemisphere.

Functional magnetic resonance imaging as a tool for investigating human cortical motor function.

Non-invasive functional magnetic resonance imaging (fMRI) mapping techniques sensitive to the local changes of blood flow, blood volume, and blood oxygenation which accompany neuronal activation have been widely used over the last few years to investigate the functional organization of human cortical motor systems, and specifically of the primary motor cortex. Validation studies have demonstrated a good correspondence between quantitative and topographic aspects of data acquired by fMRI and positron emission tomography. The spatial and temporal resolution affordable by fMRI has allowed to achieve new important information on the distributed representation of hand movements in multiple functional modules, and on the intensity and spatial extent of neural activation in the contralateral and ipsilateral primary motor cortex in relation to parametric and nonparametric aspects of movement and to the degree of handedness.

Olivofloccular circuit in oculomotor control: binocular optokinetic stimulation.

The metabolic activation of the olivocerebellar pathway during binocular optokinetic stimulation was studied in the guinea pig, by means of the semiquantitative 14C-2-deoxyglucose (2DG) technique. The experimental group underwent binocular horizontal stimulation, whereas the control animals were either kept in the dark or allowed to view a stationary pattern. The local metabolic activity index in the dorsal cap of the inferior olive was higher on the side contralateral to the eye that had been stimulated in the temporonasal (T-N) direction in the horizontal group; in contrast, the floccular region showed higher activity on the side ipsilateral to the T-N-stimulated eye.

CNS pattern of metabolic activity during tonic pain: evidence for modulation by beta-endorphin.

CNS correlates of acute prolonged pain, and the effects of partial blockade of the central beta-endorphin system, were investigated by the quantitative 2-deoxyglucose technique in unanaesthetized, freely moving rats. Experiments were performed during the second, tonic phase of the behavioural response to a prolonged chemical noxious stimulus (s.c.

Neural circuits underlying ketamine-induced oculomotor behavior in the rat: 2-deoxyglucose studies.

Time-related changes in oculomotor function and of metabolic activity patterns in selected brain networks, as assessed by the quantitative 2-deoxyglucose technique, were investigated in Long-Evans rats following intraperitoneal administration of a ketamine anesthetic dose. During ketamine-induced anesthesia a nystagmic-like behavior was present, characterized by uni-directional slow ocular drifts with superimposed paroxystic bursts of quick (saccadic-like) eye movements; all quick movements were executed in the horizontal direction, were strictly confined to an ocular hemifield of vision, and were followed by a backward (centripetal) drift. A metabolic hyperactivity was found in the dorso-medial shoulder region of the frontal cortex, corresponding to the rat saccadic cortical generator area, whereas functional activity levels were decreased in cerebellum and in several brainstem regions, including portions of the reticular formation and medial vestibular nuclei, putatively indicated as the locus of the oculomotor neural integrator.

Correlation between amount of retinal afferents to the pretectal nucleus of the optic tract and dorsal terminal accessory optic nucleus and performance of horizontal optokinetic reflex in rat.

Intraocular kainic acid injection in Long-Evans rats induces loss of retinal afferents to subcortical visual centers as assessed by the axoplasmic transport of [14C]valine. The optical terminal fields of the pretectal nucleus of the optic tract (NOT), superior colliculus and accessory optic system (AOS) nuclei appear particularly affected. Since NOT and the AOS dorsal terminal nucleus (DTN) represent the first relay station of the visuomotor pathway mediating horizontal optokinetic nystagmus (HOKR), we have studied the characteristics of HOKR after various degrees of retinal deafferentation of these nuclei induced by intraocular KA injection.

Vergence movements in comitant strabismus.

Vergence movements induced by base-out prisms were recorded, with an infrared eye tracker, for 6 patients with comitant esotropia (i.e., convergent strabismus) and anomalous retinal correspondence and for 6 normal subjects.

Correlation between retinal afferent distribution, neuronal size, and functional activity in the guinea pig medial terminal accessory optic nucleus.

The intrinsic morpho-functional organization of the medial terminal nucleus of the accessory optic system was investigated in the guinea pig. The distribution of the retinal afferents, as assessed by the axoplasmic transport of 14C-valine, showed a remarkable asymmetry within the nucleus. Thus, while the retinal terminal field covered the entire medial terminal nucleus, by far the largest density of labeled retinofugal axon terminals was found within its dorsal division.

The interstitial nucleus of the superior fasciculus, posterior bundle (INSFp) in the guinea pig: another nucleus of the accessory optic system processing the vertical retinal slip signal.

As in rabbit, gerbil, and rat, the guinea pig interstitial nucleus of the superior fasciculus, posterior bundle (INSFp) is a sparse assemblage of neurons scattered among the fibers forming the fasciculus bearing this name. Most of the INSFp neurons are small and are ovoid in shape. Interspersed among these, are a few larger, elongated neurons whose density becomes greater and whose shape becomes fusiform in correspondence to the zone of transition from the superior fasciculus to the ventral part of the medial terminal nucleus (MTN).

Vertical and horizontal visual whole-field motion differently affect the metabolic activity of the rat medial terminal nucleus.

The metabolic activity of the medial terminal nucleus (MTN) of the Accessory Optic System was studied by means of the [14C]2-deoxyglucose (2-DG) method in Long-Evans rats exposed to moving and stationary visual stimuli. In particular we explored the rate of local cerebral glucose utilization (LCGU) and the spatial distribution of 2-DG uptake within MTN related to visual stimuli capable of triggering optokinetic nystagmus. It was found that increases in MTN metabolism accompanied the retinal slip signals evoked by whole-field visual patterns moving in the vertical as well as in the horizontal direction.

Oculomotor corollary discharge in the cat pretectum.

Unit activity bursting after the onset of spontaneous eye movements made in total darkness has been recorded from the nucleus of the optic tract (NOT) of the cat pretectum. The present experiments are aimed at determining the functional significance of these neuronal reactions, namely whether the NOT discharge results from an afferent input arising from eye muscle proprioceptors or from a central signal (corollary discharge or efference copy). The results point to a central, rather than a peripheral, origin for NOT discharge.

[14C]deoxyglucose uptake of the rat visual centres under monocular optokinetic stimulation.

Monocular optokinetic stimulation ( OKS ) in Long-Evans rats enhances the uptake of [14C]2-deoxy-D-glucose (2-DG) in the pretectal nucleus of the optic tract (NOT) and superior colliculus (SC) contralaterally to the open eye regardless of the movement direction. Metabolic increases in NOT and SC are therefore found to be unrelated to the ocular nystagmus that in monocularly viewing rats follows only to OKS nasalward for the seeing eye. Since the oculomotor asymmetry has been attributed to the directional selective properties of NOT neurons responding to nasalward movement in the contralateral visual field but being inhibited by opposite ( temporalward ) movement, the enhanced 2-DG uptakes observed in the present experiments seem to represent the NOT excitatory metabolic work in the case of nasalward movement and the NOT inhibitory metabolic expenditure in the case of temporalward movement.

Optokinetic visual detection in the rat visual centres. A [14C]-2-deoxy-D-glucose study.

Following forty-five min of binocular optokinetic stimulation (OKS) the autoradiographic maps of [14C]-2-deoxy-D-glucose (2DG) assumption of Long-Evans brain reveal clearly different patterns of optical density within visual centres. The most superficial layers of superior colliculus (SC) and a pretectal area including the nucleus of the optic tract (NOT) appear symmetrically, strongly darker than other visual structures such as lateral geniculate nucleus (LGN) and visual cortex (VC). Whereas the lack of metabolic increase at LGN and VC levels entirely confirms the non-involvement of the geniculo-cortical path in mediating the optomotor response following OKS in Rodents, it is postulated that the symmetrical increase of 2DG uptake even upon unidirectional OKS found even at pretectal level may represent a commissural transfer of visual information between homologous pretectal areas like the nuclei of the optic tract.

Eye movements during the waking-sleep cycle of the encéphale isolé semichronic cat preparation.

In 'semichronic encéphale isolé (EI) cats' the spatio-temporal characteristics of eye displacements were measured with the scleral coil technique, in the dark, during active wakefulness, slow wave sleep and activated sleep. To active waking (AW) there corresponded spatial patterns of ocular movements with a clear-cut monotonous back and forth orientation in the horizontal or slightly oblique plane. Most often the AW patterns showed a periodic behaviour resulting in a true nystagmoid shape since slow, drifting deviations of the eyes were regularly followed by counter-saccades, whose speed very seldom exceeded 100 deg/sec.

Analogue analyser for on-line eye movement detection.

A system of single movement detection is obtained by discriminating the velocities and orientations of eye ball displacements. The orthogonal components of eye velocity (Vx and Vy) are generated from the horizontal (X) and the vertical (Y) components of the movements by means of two derivative circuits and the velocity modulus (V) is generated through a vector operator from Vx and Vy. The onset and end of individual movements are detected on the basis of a preselected V, Vx or Vy threshold and, for every movement thus identified, the integral function of V(t), Vx(t) or Vy(t), characteristic of the type of movement, is generated in such a way that its final value represents ball displacement.

Activity of neurons in the deep layers of the cat superior colliculus correlated with slow eye movements.

In the encéphale isolé cats in state of drowsiness and sleep and in darkness, the spike activity of a population of neurons in the superior collicules is modulated in relation to the slow movement of the eyes. These neurons are all located in the deep layers of the colliculus and belong to a larger population which had been previously to discharge in correspondence with saccadic movements. The correlation between neuronal activity and slow movements is not present continuously and may be obscured by a number of factors.

Neuronal activity correlated with eye movement in the cat's pretectum.

Single unit activity correlated with horizontal and vertical saccades was recorded in darkness from n. pretectalis anterior (NPA), n. pretectalis olivaris (NPO), n.