Incidence of the tensor of the vastus intermedius: A cadaveric study.

INTRODUCTION: The quadriceps femoris muscle is present in the anterior region of the thigh and is classically described as a muscle with four heads: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. A few years ago, a "fifth head" was described and named the tensor of the vastus intermedius (TVI). The TVI belly is in line with the belly of the vastus lateralis, and its aponeurosis imposes considerable tension on the vastus intermedius, medializing its action, to play a significant role in knee extension. OBJECTIVE: To perform a study of the TVI incidence in a Brazilian population and describe its variations. MATERIAL AND METHODS: We dissected lower limbs from cadavers previously fixed in 10% formaldehyde, belonging to the Laboratory of Anatomy of the Department of Morphology of the Biosciences Center of the Federal University of Rio Grande do Norte. RESULTS: Eighty-one lower limbs were analyzed with only 33 (40.74%) of them presenting TVI. All four types of TVI described by the literature were present in our sample with the following distribution: type 1 with 15.15%; type 2 with 9.1%; type 3 with 33.33%; type 4 with 42.42%. DISCUSSION: Although the literature points to the TVI as a normal belly of the quadriceps, making it a "quinticeps", our analysis points to the TVI as a variation and probably a matter of regionality. However, the presence of TVI is not a rare case and cannot be disregarded, which makes this study important for anatomists, physiotherapists, physicians, and surgeons.

Dopamine depletion in wistar rats with epilepsy.

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.

Basolateral amygdala inactivation impairs learned (but not innate) fear response in rats.

Numerous studies have suggested that the amygdala is involved in the formation of aversive memories, but the possibility that this structure is merely related to any kind of fear sensation or response could not be ruled out in previous studies. The present study investigated the effects of bilateral inactivation of the amygdaloid complex in rats tested in the plus-maze discriminative avoidance task. This task concomitantly evaluates aversive memory (by discrimination of the two enclosed arms) and innate fear (by open-arm exploration). Wistar rats (3-5 months-old) were implanted with bilateral guide cannulae into basolateral amygdala. After surgery, all subjects were given 1 week to recover before behavioral experiments. Afterwards, in experiment 1, 15 min prior to training, 0.5 µl of saline or muscimol (1 mg/ml) was infused in each side via microinjection needles. In experiment 2 the animals received injections immediately after the training session and in experiment 3 rats were injected prior to testing session (24 h after training). The main results showed that (1) pre-training muscimol prevented memory retention (evaluated by aversive arm exploration in the test session), but did not alter innate fear (evaluated by percent time in open arms); (2) post-training muscimol impaired consolidation, inducing increased percent in aversive arm exploration in the test session and (3) pre-testing muscimol did not affect retrieval (evaluated by aversive enclosed arm exploration in the test session). The results suggest that amygdala inactivation specifically modulated the learning of the aversive task, excluding a possible secondary effect of amygdala inactivation on general fear responses. Additionally, our data corroborate the hypothesis that basolateral amygdala is not the specific site of storage of aversive memories, since retention of the previously learned task was not affected by pre-testing inactivation.

A public health approach to increase treatment of latent TB among household contacts in Brazil.

SETTING: Two consecutive trials were conducted to evaluate the effectiveness of a public health approach to identify and correct problems in the care cascade for household contacts (HHCs) of TB patients in three Brazilian high TB incidence cities.METHODS: In the first trial, 12 clinics underwent standardised evaluation using questionnaires administered to TB patients, HHCs and healthcare workers, and analysis of the cascade of latent TB care among HHCs. Six clinics were then randomised to receive interventions to strengthen management of latent TB infection (LTBI), including in-service training provided by nurses, work process organisation and additional clinic-specific solutions. In the second trial, a similar but streamlined evaluation was conducted in two clinics, who then received initial and subsequent intensive in-service training provided by a physician.RESULTS: In the evaluation phase of both trials, many HHCs were identified, but few started LTBI treatment. After the intervention, the number of HHCs initiating treatment per 100 active TB patients increased by 10 (95%CI - 11 to 30) in the first trial, and by 44 (95%CI 26 to 61) in the second trial.DISCUSSION: A public health approach with standardised evaluation, local decisions for improvements, followed by intensive initial and in-service training appears promising for improved LTBI management.

Nuclear organization and morphology of cholinergic neurons in the brain of the rock cavy (Kerodon rupestris) (Wied, 1820).

The aim of this study was to conduct cytoarchitectonic studies and choline acetyltransferase (ChAT) immunohistochemical analysis to delimit the cholinergic groups in the encephalon of the rock cavy (Kerodon rupestris), a crepuscular Caviidae rodent native to the Brazilian Northeast. Three young adult animals were anesthetized and transcardially perfused. The encephala were cut in the coronal plane using a cryostat. We obtained 6 series of 30-µm-thick sections. The sections from one series were subjected to Nissl staining. Those from another series were subjected to immunohistochemistry for the enzyme ChAT, which is used in acetylcholine synthesis, to visualize the different cholinergic neural centers of the rock cavy. The slides were analyzed using a light microscope and the results were documented by description and digital photomicrographs. ChAT-immunoreactive neurons were identified in the telencephalon (nucleus accumbens, caudate-putamen, globus pallidus, entopeduncular nucleus and ventral globus pallidus, olfactory tubercle and islands of Calleja, diagonal band of Broca nucleus, nucleus basalis, and medial septal nucleus), diencephalon (ventrolateral preoptic, hypothalamic ventrolateral, and medial habenular nuclei), and brainstem (parabigeminal, laterodorsal tegmental, and pedunculopontine tegmental nuclei). These findings are discussed through both a functional and phylogenetic perspective.

Cocaine- and amphetamine-regulated transcript is overexpressed in the anteroventral periventricular nucleus of pregnant rats.

The anteroventral periventricular nucleus (AVPV) is sexually dimorphic, presenting a higher neuronal density in females. The AVPV contains a dense collection of oestrogen and progesterone receptors and has been related to the modulation of gonadotrophin-releasing hormone (GnRH) secretion and gene expression in response to circulating hormonal levels. It has been suggested that cocaine- and amphetamine-regulated transcript (CART) is also related to reproductive control because CART immunoreactive fibres are in close apposition with GnRH neurones. A portion of these fibres originate in the AVPV but its role in mediating hormonal action needs to be better explored. We hypothesised that CART expression in the AVPV would be influenced by the reproductive state and, consequently, by hormonal levels. To test this hypothesis, we analysed CART expression in the AVPV of female rats in different reproductive states (pro-oestrous, pregnancy and lactation). We found that, on the 19th day of pregnancy, female rats presented increased CART expression. Our findings indicate that AVPV CART expression is influenced by the reproductive state and that CART neurones in the AVPV may play a role in the hormonal mechanisms involved in the induction of maternal behaviour.

Influence of the drying conditions of Sargassum sp. alga on the bioadsorption of hexavalent chromium.

Industrial wastes containing synthetic organic compounds and heavy metals are among the most dangerous residues, whose growth has followed the increase in industrial activity. Heavy metals are readily assimilated into the food chain and therefore easily accumulated in the ecosystem. To remove heavy metals from aqueous solutions, marine algae may be used as adsorbents either in their natural form or after treatments by a cross-linking process to improve their mechanical resistance. Drying of biosorbents, such as marine algae, is mentioned in many previous works as a step preceding the adsorption/dessorption cycle. Concerning algae, drying of its fresh biomass allows for proper storage and enhances performance in the sorption of heavy metals. In this work, physical and morphological analyses of fresh and dried Sargassum sp. marine algae, harvested offshore São Sebastião, São Paulo state, Brazil, were performed in order to assess the influence of drying conditions on the biosorption process. Chromium concentrations were also determined in different parts of the algal structure before and after the biosorption process. The drying promoted structural changes in the algae, like shrinkage and porosity reduction. It was also observed that the chromium retention was dependent on the structural arrangement of the alga parts, in which the leaf was the major biosorbent.

Intravascular source of adenosine during forearm ischemia in humans: implications for reactive hyperemia.

It is believed that adenosine is released in ischemic tissues and contributes to reactive hyperemia. We tested this hypothesis in the human forearm using microdialysis to estimate interstitial and intravascular levels of adenosine and caffeine withdrawal to potentiate endogenous adenosine and determine its effect on reactive hyperemia. Forearm blood flow response to ischemia was measured by air plethysmography before and 60 hours after the last dose of caffeine (250 mg TID for 7 days, n=6). Forearm blood flow increased by 274+/-66% and 467+/-97% after 3 minutes of forearm ischemia, before and during caffeine withdrawal, respectively (P<0.05). Thus, caffeine withdrawal enhances reactive hyperemia. To determine the source of adenosine, we measured interstitial adenosine with the use of a microdialysis probe inserted into the flexor digitorum superficialis muscle of the forearm, and we measured intravascular adenosine with the use of a microdialysis probe inserted retrogradely into the medial cubital vein. Dialysate samples were collected at 15-minute intervals during resting, forearm ischemia, and recovery periods. Forearm ischemia failed to increase muscle dialysate concentrations of adenosine but did increase intravascular dialysate adenosine 2.1-fold, from 0.61+/-0.12 to 1.28+/-0.39 micromol/L (P<0.01, n=8). Intravascular dialysate concentrations of thromboxane B2 did not increase during ischemia, ruling out platelet aggregation as a source of adenosine. These results support the hypothesis that endogenous adenosine contributes to reactive hyperemia and indicate that the major source of adenosine in the human forearm is intravascular. We speculate that endothelial cells are the source of intravascular adenosine during ischemia.

Retinohypothalamic projections in the common marmoset (Callithrix jacchus): A study using cholera toxin subunit B.

Retinal projections in vertebrates reach the primary visual, accessory optic, and circadian timing structures. The central feature of the circadian timing system is the principal circadian pacemaker, the suprachiasmatic nucleus (SCN) of the hypothalamus. The direct projections from the retina to the SCN are considered the entrainment pathway of the circadian timing system. In this study, unilateral intravitreal injections of cholera toxin subunit B were used to trace the retinal projections to the marmoset hypothalamus. The retinohypothalamic tract reaches the ventral suprachiasmatic nucleus bilaterally, as anticipated from previous studies. However, labeled fibers were found in several other hypothalamic regions, such as the medial and lateral preoptic areas, supraoptic nucleus, anterior and lateral hypothalamic areas, retrochiasmatic area, and subparaventricular zone. These results reveal new aspects of retinohypothalamic projection in primates and are discussed in terms of their implications for circadian as well as noncircadian control systems.

Food consumed does not account for the higher prevalence of obesity among stunted adults in a very-low-income population in the Northeast of Brazil (Maceió, Alagoas).

OBJECTIVE: To study the food pattern of stunted and nonstunted, obese and nonobese individuals in a very-low-income population. DESIGN: A household survey. SETTING: Slum set up by the 'Homeless Movement', city of Maceió (Alagoas), Brazil. SUBJECTS AND METHODS: A total of 532 adults classified by sex, stature (Z -2s.d. of the NCHS curves), and body mass index (BMI) were compared using the following variables: waist circumference, waist-hip circumference ratio (W/H), percentage body fat (skinfold thickness and bioelectrical impedance), and food intake (24-h recall). RESULTS: The prevalence of stunting was 22.6%. In all, 30% of the stunted subjects were overweight or obese, compared with 23% for the nonstunted individuals (P<0.05). In women, logistic regression analysis showed a strong association among weight, abdominal fat, and stunting (r=0.81). No significant differences were observed in the values of W/H or in the qualitative menu of the different categories. Energy intake was below the RDA figures (about 63%). There was similarity among the groups regarding the proportion of macronutrients, except for the fact that stunted obese women ingested less fat and protein than nonstunted obese women. Stunted obese individuals consumed less energy (5962 kJ) than the population as a whole (6213 kJ), an amount far lower than their average needs, which were calculated on the basis of their shorter stature (8109 kJ). CONCLUSION: The observed energy consumption seems compatible with the panorama of undernutrition present in the population, but it does not explain the high prevalence of obesity detected.

[Estimation of blood pressure in children using a regression equation]. / Estimativa da pressão arterial em crianças por equação de regressão.

Blood pressure was determined at the Instituto de Educação do Rio de Janeiro in apparently normal school children, aged 5 to 12 years. Among the 2045 school children, 12 were considered unfit for the study as they presented symptoms of illnesses which could affect the results. The total number was, then, reduced to 2033 children--689 boys and 1344 girls. The blood pressure was measured by auscultatory method of the right arm with children lying supine. A mercury manometer and cuffs of adequate sizes were used. A record of pulse rate, weight and height was also obtained. Normal maximum limits of blood pressure was established according to the 95th percentile. The correlations of weight, height and blood pressure were determined and a regression equation could be elaborated; thus, one can obtain an estimated blood pressure from a child's weight and height.

Influence of caffeine on blood pressure and platelet aggregation.

OBJECTIVE: Studies have demonstrated that methylxanthines, such as caffeine, are A1 and A2 adenosine receptor antagonists found in the brain, heart, lungs, peripheral vessels, and platelets. Considering the high consumption of products with caffeine in their composition, in Brazil and throughout the rest of the world, the authors proposed to observe the effects of this substance on blood pressure and platelet aggregation. METHODS: Thirteen young adults, ranging from 21 to 27 years of age, participated in this study. Each individual took 750 mg/day of caffeine (250 mg tid), over a period of seven days. The effects on blood pressure were analyzed through the pressor test with handgrip, and platelet aggregation was analyzed using adenosine diphosphate, collagen, and adrenaline. RESULTS: Diastolic pressure showed a significant increase 24 hours after the first intake (p<0.05). This effect, however, disappeared in the subsequent days. The platelet aggregation tests did not reveal statistically significant alterations, at any time during the study. CONCLUSION: The data suggest that caffeine increases diastolic blood pressure at the beginning of caffeine intake. This hypertensive effect disappears with chronic use. The absence of alterations in platelet aggregation indicates the need for larger randomized studies.

[Prevalence and sociocultural and economic aspects of hypertension in a health center of the northern area of Manaus]. / Prevalência e aspectos sócio-culturais e econômicos da hipertensão arterial em centro de saúde da zona norte de Manaus.

PURPOSE: To verify the prevalence and the possible sociocultural and economic factors involved in high blood pressure (HBP), intending to contribute to the elaboration of public health programs. METHODS: The blood pressure of 1,766 individuals, aging 13 years old or more, was measured by the auscultatory method, using a stethoscope and a sfigmomanometer. It was included in the HBP group, the individual presenting blood pressure above 140 x 90 mmHg in two measurements on different occasions. These individuals answered a form searching for sociocultural and economic aspects. RESULTS: Among the individuals examined, 76 were considered to have HBP. There was an increase on the prevalence of HBP with an increase of age, being the greatest among the individuals aging 49 years or more. It was observed significant association between age and HBP (p < 0.05), but the same did not happen with sex or skin color. In most part of the individuals with HBP, it was observed low family income and low educational level. Half of the HBP patients were used to eat with salt and fat. CONCLUSION: The educational level, economic status, and sociocultural habits of a person constitute factors that must be considered in the development of public health programs for control and reduction of the prevalence of HBP.

[Blood pressure responses in children of normotensive and of hypertensive parents treated with pressor stimulus]. / Comportamento da pressão arterial em filhos de normotensos e filhos de hipertensos submetidos a estímulos pressóricos.

PURPOSE: To compare cardiovascular reactivity in adolescents with and without family history of hypertension. METHODS: Thirty two subjects, males, students, aging between 13 to 18 years old were examined. One half of them had no family history of hypertension and the other half had at least one hypertensive parent. Basal blood pressure level was obtained before the application of the following selected tests: isometric handgrip exercise test, cold pressor test and arithmetic mental stress test. The blood pressure values were obtained by a digital, oscilometric device, previously calibrated. RESULTS: The subjects with family history of hypertension exhibited higher basal levels of both systolic and diastolic blood pressure (p < 0.10). Concerning the tests applied, the subjects with family history of hypertension also exhibited higher responses, but only the responses of the diastolic blood pressure to the mental stress test was statistically significant (p < 0.10). CONCLUSION: Our findings point to the need of a special follow-up of children with a family history of hypertension.

[Cancellation of scheduled surgery at a university hospital: an exploratory study]. / Cancelamento de cirurgias programadas em um hospital-escola: um estudo exploratório.

In spite of the extensive available literature on surgery patients' preparation and on the performance of surgeries, the focus given to the cancellation of the surgical act has been quite restricted. This study aims at identifying the number of scheduled and cancelled surgeries as well as the services that are mostly affected by such cancellations and was carried out in the surgery service of a big public university hospital located in the metropolitan area of Fortaleza, Ceará. The data were collected through surgery registration books, daily maps of surgery schedules and from the files of patients scheduled for surgery from September to December, 1996. The gathered data were analyzed quantitatively and introduced in charts. The results demonstrate that from the 1,145 surgeries programmed in the selected period, 379 (33%) had been cancelled. The mostly prejudiced services were General Surgery, Ophthalmology, Head and Neck Surgery, Trauma and Orthopedics, Otorhinolaryngology, Nephrology and Renal Transplant, and Proctology. Further investigation in this area in order to know the determinant causes of surgery cancellation as well as the participation of nursing in the study of this problem are necessary.

Expression of cocaine- and amphetamine-regulated transcript in the rat forebrain during postnatal development.

Cocaine- and amphetamine-regulated transcript (CART) is widespread in the rodent brain. CART has been implicated in many different functions including reward, feeding, stress responses, sensory processing, learning and memory formation. Recent studies have suggested that CART may also play a role in neural development. Therefore, in the present study we compared the distribution pattern and levels of CART mRNA expression in the forebrain of male and female rats at different stages of postnatal development: P06, P26 and P66. At 6 days of age (P06), male and female rats showed increased CART expression in the somatosensory and piriform cortices, indusium griseum, dentate gyrus, nucleus accumbens, and ventral premammillary nucleus. Interestingly, we found a striking expression of CART mRNA in the ventral posteromedial and ventral posterolateral thalamic nuclei. This thalamic expression was absent at P26 and P66. Contrastingly, at P06 CART mRNA expression was decreased in the arcuate nucleus. Comparing sexes, we found increased CART mRNA expression in the anteroventral periventricular nucleus of adult females. In other regions including the CA1, the lateral hypothalamic area and the dorsomedial nucleus of the hypothalamus, CART expression was not different comparing postnatal ages and sexes. Our findings indicate that CART gene expression is induced in a distinct temporal and spatial manner in forebrain sites of male and female rats. They also suggest that CART peptide participate in the development of neural pathways related to selective functions including sensory processing, reward and memory formation.

Immunocytochemical characterization of the pregeniculate nucleus and distribution of retinal and neuropeptide Y terminals in the suprachiasmatic nucleus of the Cebus monkey.

Circadian rhythms generated by the suprachiasmatic nucleus (SCN) are modulated by photic and non-photic stimuli. In rodents, direct photic stimuli reach the SCN mainly through the retinohypothalamic tract (RHT), whereas indirect photic stimuli are mainly conveyed by the geniculohypothalamic tract (GHT). In rodents, retinal cells form a pathway that reaches the intergeniculate leaflet (IGL) where they establish synapses with neurons that express neuropeptide Y (NPY), hence forming the GHT projecting to the SCN. In contrast to the RHT, which has been well described in primates, data regarding the presence or absence of the IGL and GHT in primates are contradictory. Some studies have suggested that an area of the pregeniculate nucleus (PGN) of primates might be homologous to the IGL of rodents, but additional anatomical and functional studies on primate species are necessary to confirm this hypothesis. Therefore, this study investigated the main histochemical characteristics of the PGN and the possible existence of the GHT in the SCN of the primate Cebus, comparing the distribution of NPY immunoreactivity, serotonin (5-HT) immunoreactivity and retinal terminal fibers in these two structures. The results show that a collection of cell bodies containing NPY and serotonergic immunoreactivity and retinal innervations are present within a zone that might be homologous to the IGL of rodents. The SCN also receives dense retinal innervations and we observed an atypical distribution of NPY- and 5-HT-immunoreactive fibers without regionalization in the ventral part of the nucleus as described for other species. These data may reflect morphological differences in the structures involved in the regulation of circadian rhythms among species and support the hypothesis that the GHT is present in some higher primates (diurnal animals).

Calcium-binding proteins in the circadian centers of the common marmoset (Callithrix jacchus) and the rock cavy (Kerodon rupestris) brains.

The hypothalamic suprachiasmatic nucleus (SCN) and the thalamic intergeniculate leaflet (IGL) are considered to be the main centers of the mammalian circadian timing system. In primates, the IGL is included as part of the pregeniculate nucleus (PGN), a cell group located mediodorsally to the dorsal lateral geniculate nucleus. This work was carried out to comparatively evaluate the immunohistochemical expression of the calcium-binding proteins calbindin D-28k (CB), parvalbumin (PV), and calretinin (CR) into the circadian brain districts of the common marmoset and the rock cavy. In both species, although no fibers, terminals or perikarya showed PV-immunoreaction (IR) into the SCN, CB-IR perikarya labeling was detected throughout the SCN rostrocaudal extent, seeming to delimit its cytoarchitectonic borders. CR-IR perikarya and neuropil were noticed into the ventral and dorsal portions of the SCN, lacking immunoreactivity in the central core of the marmoset and filling the entire nucleus in the rock cavy. The PGN of the marmoset presented a significant number of CB-, PV-, and CR-IR perikarya throughout the nucleus. The IGL of the rocky cavy exhibited a prominent CB- and CR-IR neuropil, showing similarity to the pattern found in other rodents. By comparing with literature data from other mammals, the results of the present study suggest that CB, PV, and CR are differentially distributed into the SCN and IGL among species. They may act either in concert or in a complementary manner in the SCN and IGL, so as to participate in specific aspects of the circadian regulation.