A study of Culicoides in Rondônia, in the Brazilian Amazon: species composition, relative abundance and potential vectors.

There is very little information available about Culicoides species (Diptera: Ceratopogonidae) in the western Brazilian Amazon. However, studies of the fauna of this region are essential to knowledge of the species and potential vectors within it. Thus, the present study aims to evaluate the abundance, richness and composition of Culicoides species in rural areas in the state of Rondônia, Brazil. Culicoides specimens were collected in forest and pasture environments in the municipality of Porto Velho, using light traps. A total of 1708 individuals (1136 females and 572 males) belonging to 33 species were collected; 28 of these samples represent new records for the state of Rondônia and include the first record of Culicoides contubernalis in Brazil. Culicoides insignis was the most abundant species (86.1%). Species richness was greater in forest areas (32 species, 96.96%), whereas pastures presented the greatest number of Culicoides captured (n = 1540, 90.1%). This study shows that Culicoides populations differ between forest and pasture environments and indicates that the abundance of C. insignis is an important factor in epidemiological vigilance studies in the region.

Cytochrome oxidase and NADPH-diaphorase on the afferent relay branch of the optokinetic reflex in the opossum.

In the present study, histochemical techniques combined with more conventional anatomical methods were used to refine the identification of the nucleus of the optic tract and the nuclei of the accessory optic system in the opossum. The distribution of the enzyme cytochrome oxidase (CO) was examined in the cells and the neuropil of the opossum's mesodiencephalic region. Strong CO labeling was present in the nucleus of the optic tract (NOT)-dorsal terminal nucleus (DTN). Alternate sections, taken from animals that had received bilateral injections of horseradish peroxidase centered in the region of the inferior olive, were subjected to assays for CO and horseradish peroxidase. The region occupied by CO-labeled cells in the NOT-DTN superimposed with the one defined by retrogradely labeled cells. Cell counts along the NOT-DTN anteroposterior axis revealed that although the olivary and CO-positive cells were confined within similar boundaries, the latter are up to twofold more numerous than the former. As revealed by cytochrome oxidase histochemistry, the outlines of the NOT-DTN, the other pretectal nuclei and the nuclei belonging to the accessory optic system coincided with those revealed by the histochemistry for nicotinamide dinucleotide phosphate diaphorase (NADPH-d). After an intraocular injection of cholera toxin beta subunit and alternate sections processing for NADPH-d and CO, the distribution of labeled retinal terminal fields in the mesodiencephalic region was shown to be coincident with regions of high levels of histochemical labeling. These results are discussed in the light of previous anatomofunctional assessments of the pretectum and accessory optic system.

[Indeterminate Hansen's disease]. / Hanseníase indeterminada.

The AA have characterized undifferenciated or indeterminate forms of Hanseniasis on the clinical, immunological, bacteriological and histological aspects. They too signaled the epidemiological importance and demonstrated its position in the statistics showing it to be the prevalent form of the disease. In 90 patients from Rio de Janeiro they discussed the many clinical manifestations and the therapeutics, prognosis, evolution and most important manners to discovered new cases.

[Juvenile atrophying erythema multiforme]. / Eritema multiforme infantil atrofiante.

This is a case report of an Atrophic Juvenile Erythema Multiform that has occurred in a ten year old white girl. She has been having symptoms since age three, presenting severe flares of lesions that looked like multiform erythema. When the lesions healed a loose scar was left involving the whole skin. Some of the histological and pathogenic mechanisms of the disease are discussed.

[Disseminated mycosis fungoides]. / Micose fungoide disseminada.

A case of mycosis fungoides (MF) that began with cutaneous eritemato-papular lesions leading to death with neurological symptoms is reported. Cutaneous histophatology was typical to MF and the liquoric citology showed Sézary cells. Necropsy evidenced extra-cutaneous dissemination of the tumor involving lymphnodes, heart, digestive system, bladder, liver, bone marrow and leptomeninges. The uncommon clinical manifestations and evolution are discussed.

Positioning of borderline and indetermined groups in the hanseniasis classification.

The authors discuss the present conceptions of the hanseniasis classification, establish the main clinical, histological, bacterioscopic and immunological characteristics of the borderline and indeterminate groups. They also believe that the borderline group is genetically pre-determined and show the importance of the indeterminate forms and its evolutionary aspects. They try a schematic process of classification from the Rabello's polar conception and conclude stating that the closing of the borderline groups within itself, with special characteristics, oscillating in a defined spectrum without touching the extremes T and V (L).

Binocularity in the nucleus of the optic tract of the opossum.

In the present work, we characterize electrophysiologically a commissural subcortical pathway which is related to binocular interactions in the nucleus of the optic tract (NOT) of the opossum. The main role played by the circuit comprising this pathway seems to be in relaying information coming from the ipsilateral eye to the NOT. The strongest evidence comes from experiments in which lidocaine was injected into the NOT and the ensuing effects in the opposite nucleus were monitored under ipsilateral monocular stimulation. It was consistently observed that during action of lidocaine the directional response normally elicited by stimulation of the ipsilateral eye did not take place in the NOT opposite to the silenced nucleus. This effect was reverted in a few minutes after recovery of the injected NOT. The response to stimulation of the contralateral eye, though, was not affected by this procedure.

The nucleus of the optic tract of the opossum.

This paper reviews anatomical and electrophysiological data on the nucleus of the optic tract (NOT) of the opossum, a nucleus in the afferent branch of the horizontal optokinetic reflex. It is proposed that subcortical routes are essential for responses from the two eyes: a direct retinal projection from the contralateral eye and a commissural pathway between the two NOTs for the ipsolateral eye. In the latter case there's evidence that the commisural axons have a relay on inhibitory neurones. This circuit accounts for the differences in response pattern under monocular condition: temporo-nasal motion of the visual stimulus elicits excitation in the contralateral NOT, resulting in inhibition of the ipsolateral nucleus, while naso-temporal motion promotes inhibition in the contralateral nucleus, releasing the ipsolateral nucleus from the commissural input.

Postura da mão e imagética motora: um estudo sobre reconhecimento de partes do corpo / Hand posture and motor imagery: a body-part recognition study

OBJETIVOS: Assim como a imagética motora, o reconhecimento de partes do corpo aciona representações somatosensoriais específicas. Essas representações são ativadas implicitamente para comparar o corpo com o estímulo. No presente estudo, investigou-se a influência da informação proprioceptiva da postura no reconhecimento de partes do corpo (mãos) e propõe-se a utilização dessa tarefa na reabilitação de pacientes neurológicos. MATERIAIS E MÉTODOS: Dez voluntários destros participaram do experimento. A tarefa era reconhecer a lateralidade de figuras da mão apresentada, em várias perspectivas e em vários ângulos de orientação. Para a figura da mão direita, o voluntário pressionava a tecla direita e para a figura da mão esquerda, a tecla esquerda. Os voluntários realizavam duas sessões: uma com as mãos na postura prona e outra com as mãos na postura supina. RESULTADOS: Os tempos de reação manual (TRM) eram maiores para as vistas e orientações, nas quais é difícil realizar o movimento real, mostrando que durante a tarefa, existe um acionamento de representações motoras para comparar o corpo com o estímulo. Além disso, existe uma influência da postura do sujeito em vistas e ângulos específicos. CONCLUSÕES: Estes resultados mostram que representações motoras são ativadas para comparar o corpo com o estímulo e que a postura da mão influencia esta ressonância entre estímulo e parte do corpo.

OBJECTIVE: Recognition of body parts activates specific somatosensory representations in a way that is similar to motor imagery. These representations are implicitly activated to compare the body with the stimulus. In the present study, we investigate the influence of proprioceptive information relating to body posture on the recognition of body parts (hands). It proposes that this task could be used for rehabilitation of neurological patients. METHODS: Ten right-handed volunteers participated in this experiment. The task was to recognize the handedness of drawings of a hand that were presented in different perspectives and several orientations. For drawings of a right hand, the volunteers pressed the right key, and for drawings of a left hand, they pressed the left key. The volunteers underwent two sessions: one with their hands in a prone posture and the other with their hands in a supine posture. RESULTS: The manual reaction time was longer for perspectives and orientations for which the real movement was difficult to achieve. This showed that, during the task, motor representations were activated to compare the body with the stimulus. Furthermore, the subject's posture had an influence in relation to specific perspectives and orientations. CONCLUSIONS: These results showed that motor representations are activated to compare the body with the stimulus, and that the position of the hand influences this resonance between the stimulus and the body part.

Mental rotation of anthropoid hands: a chronometric study

It has been shown that mental rotation of objects and human body parts is processed differently in the human brain. But what about body parts belonging to other primates? Does our brain process this information like any other object or does it instead maximize the structural similarities with our homologous body parts? We tried to answer this question by measuring the manual reaction time (MRT) of human participants discriminating the handedness of drawings representing the hands of four anthropoid primates (orangutan, chimpanzee, gorilla, and human). Twenty-four right-handed volunteers (13 males and 11 females) were instructed to judge the handedness of a hand drawing in palm view by pressing a left/right key. The orientation of hand drawings varied from 0° (fingers upwards) to 90° lateral (fingers pointing away from the midline), 180° (fingers downwards) and 90° medial (finger towards the midline). The results showed an effect of rotation angle (F(3, 69) = 19.57, P < 0.001), but not of hand identity, on MRTs. Moreover, for all hand drawings, a medial rotation elicited shorter MRTs than a lateral rotation (960 and 1169 ms, respectively, P < 0.05). This result has been previously observed for drawings of the human hand and related to biomechanical constraints of movement performance. Our findings indicate that anthropoid hands are essentially equivalent stimuli for handedness recognition. Since the task involves mentally simulating the posture and rotation of the hands, we wondered if "mirror neurons" could be involved in establishing the motor equivalence between the stimuli and the participants' own hands.