53 resultados para Miriam Colwell
Resumo:
Exploratory descriptive study, with a quantitative approach and prospective data, performed in Pronto Socorro Clóvis Sarinho (PSCS), in Natal/RN, aiming to analyze care given by the nursing and medical staff to victims of violence attended to in an emergency hospital in Natal/RN; to identify care given by the nursing and medical staff as viewed by the victims; to compare data observed during the process of care with the victim s view on the care given by the nursing and medical staff; to identify the existing knowledge on violence and the process of caring for victims and its relation with prejudice; to identify obstacles and perspectives for prevention during the process of caring for victims in the emergency services. The population consisted of 97 physicians, 16 nurses, 75 nursing technicians and assistants and 365 victims of violence, with data collected from April to May 2009. Out of 188 professionals, 52.1% are female; 32% were aged 41 to 50; 99.5% had given care to a victim of violence; 90.4% reported to have given care to patients under custody; among these, 17.3% felt prejudice; 55.3% stated they don t provide different care for assaulted victims and assailants, however 44.7% stated they do; 86.7% feel their workplace is unsafe; 61.7% denied the existence of any obstacle and 38.3% reported the existence of obstacles; among these, 26.1% referred to inadequate facilities; 37.8% believe reinforcing security and professional training are the main solutions. Among the 365 researched violence victims, 82.2% were assaulted; male (69.6%); aged 18 to 24 (24.9%); hailing from the Greater Natal area (89.9%); on 19.7% the event happened on Saturday; during the night (48.8%); victim of physical assault (61.4%); produced by body force (27.7%); 24.4% were injured in the head and neck. 57% had used some drug, among which alcohol was predominant (75.5%). On 621 observations performed during the victim care process, when compared to the report of assaulted victims, there was a statistical difference, at 5% significance level, regarding reception, resistance from the professionals, questioning about the violent event, providing of guidance, interaction with the patient and the understanding of receiving proper care, and care resolution. In comparisons involving the observed and the assailant victims reports, there was a statistical difference regarding the resence of resistance from the professionals, performance of necessary procedures and the nteraction with the patient and the understanding of receiving proper care and 58.1% reported the nursing team was the one that provided the best care. We conclude that professionals had lready given care to assailant patients, acknowledge the importance of knowing how the vent took place and acquired this preparation during their practice. The most often referred bstacles that hinder assistance were: inadequate facilities, material deficit and lack of rofessional preparation. As solutions for these problems, they cited the reinforcement of ecurity and professional training
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Descriptive exploratory study, prospective with quantitative approach, performed on the Medical Regulation Central of SAMU/Natal, aiming to identify the level of professional satisfaction of the members of the nursing team working at SAMU/Natal; and verify the degree of importance attributed by the professionals to each of the components Professional Satisfaction: autonomy, interaction, professional status , work requirements, organizational rules and remuneration. The population was of 60 professionals, with data collected from january to february 2005. We used an instrument translated and validated by Lino (1999) to the portuguese language, the Professional Satisfaction Rate (PSR). The results demonstrate that there was a slight predominance of the female gender (54,9%); aged between 36 and 45 years old (60,8%); married (58,8%), 82,4% with children, 30,8% aged between 05 and 09. Regarding formation, we observed that 78,4% were nursing technicians and 21,6% nurses, formed for 11 to 15 years (17,5%). From the 11 nurses, 09 (81,8%) informed they have specialization, 29,4% of the team has been working for 11 to 15 years on the urgency area, 58.8% works for more than 02 years on SAMU, 72,6% of the team members have fixed work schedules. There was homogeneity on the work shifts: 41,2% on the day shift and 53% on the night shift. Regarding the reason to be working on SAMU, 64% chose to work in the service, and among these 76,3% predominantly perform direct care to the patients, 96,1% like and are satisfied to work in the service. Regarding the remuneration, 90,9% informed they receive 05 to 10 minimum wages; 70% of the technicians informed they receive -2 to 05 minumum wages, 50,1% informed they receive no additional benefit. The analysis of PSR through Cronbach s Alpha Coeficient resulted on the value of 0,94 and through Kendall s Tau Coeficient on 0,87, demonstrating to be a trustworthy instrument to measure the level of professional satisfaction of the SAMU nursing team, in our environment. As for the level of importance attributed to the components of professional satisfaction, we indentified that the nursing team considered the Autonomy component as the most important, followed by the component Remuneration, Interaction, Work Requirements, Work Requirements, Organizational Rules and Professional Status . Regarding the current level of professional satisfaction, we identified they were most satisfied with the Professional Status , Autonomy, Interaction, Remuneration, Work Requirements and Organizational Rules. The real professional satisfaction level, calculated through statistics, however, tells these professionals are more satisfied with Autonomy, Remuneration, Interaction, Work Requirements, professional Status and Organizational Rules. The PSR in our work was of 8,6, indicating the SAMU Natal nursing team has little satisfaction on their work environment
Resumo:
Nursing as a profession goes in search on quality of their care through new frameworks, trying to break postures of the health care system so fragmented in the care. To change professional practices, it is necessary to build their own knowledge grounded on Nursing Care System. The aim of this study was to analyze the influence of nurses' knowledge on care systematization in nursing in the University Hospital Natal-RN. It is an analytical descriptive study carried out at the Onofre Lopes University Hospital (HUOL), Natal-RN, 2010, the sample was composed of 40 active nurses working in hospitalization units of the hospital, the inclusion criteria were being in the monthly scale sector and agree to participate in the study. The non-participant observation and another interview were used for collecting data, statistical analysis was descriptive and inferential with reliability test, Pearson test, chi-square and Fischer, the variables that correlated were analyzed in a model Multiple logistic , calculating odds ratio. The results were: predominance of female professionals (90%), predominantly in the age range 39-46 years (37.5%), nurses who have the undergraduate degree at the Federal University of Rio Grande do Norte (80%), and who have expertise training as a minimal degree (62.5%). Among the surveyed, the knowledge showed significance with the graduation time (p = 0.018) and time working in HUOL (p = 0.036). The majority of the professionals surveyed do not know which organ is responsible for the SAE legislation (52.5%), aware of the steps needed to build the nursing diagnosis (92.5%), understand the characteristics of nursing planning (90% ). However the same professionals do not perform physical examination in patients (50.0%) did not classify the clinical findings (68.4%), and identify the problems encountered as a classification (13.2%). The planning of nursing care is carried out by verbal order of nurses (82.5%), 41% of the professionals assess only the intervention stage, in other words, the actions taken. Regarding the practical application of nursing records 53% of nurses do not realize records, 30.8% is incomplete, the other held notes (p = 0.003). The nurses know the nursing process (90% of appropriate responses), despite the actions defined by the theory are not applied in practice. Investigators believe the condition of the hospital teacher (22.5%) could positively affect the implementation of the SAE associated with the interest of professionals (20%). Of the respondents, 17.5% accept as truth the lack of facilities to assist the SAE implementation in the hospital. It was concluded that nurses know the theory that underlies the SAE and the nursing process, but do not develop the service know as well, there is need for action to boost the SAE implementation as practice of nurses in the hospital investigated
Resumo:
It is an exploratory and descriptive study made by a quantitative approach, developed among February and May 2010, aiming to assess the pain of patients underwent abdominal surgeries in a University Hospital, in Natal/RN; to identify the local and intensity of the pain based on Numerical Estimative Scale; to analyze the pain related to the sensorial-discriminative, motivational-affective and cognitive-assessment dimensions, using the McGill Questionnaire pain; to establish a relation between the pain process and age, gender, religion, and king of surgery; to identify the medicines efficiency used to control postoperative pain. The sample was composed by 253 patients underwent abdominal surgeries. The results showed a total of 63.63% females between 38 and 47 years of age (21.34%); illiterates (21.73%); married (64.03%), living in Natal and surroundings (67.97%) and Catholics (74.30%). In their first assessment, 84.19% showed postoperative pain; the pain was considered light in 18.97% of them, moderate in 21.74% and severe in 43.48%. The mean number of descriptors chosen through the McGill Questionnaire Pain was 10.78 (DP= 6.09) and pain rating 23.65 (DP= 15.93). The descriptors selected with higher frequency were: sickening pain (69.01%), tired (65.25%), thin (62.44%), bored (58.69%), ardor (46.48%), pointed (38.50%) and colic (35.21%). In their second assessment, 57.71% of patients didn t relate any postoperative pain and 42.29% were still complaining about the pain. After taking analgesic medication, just 41.90% of patients who had complete pain relief. The Pharmacological groups most used were: simple analgesic (37.86%), weak opioids (32.98%), AINES (19.85%) and strong opioid (9.31%). It was not found a significant postoperative pain variation related to the sexes, religion and kind of surgery. It was concluded there were a high level in the number of patients with postoperative pain, mainly in a severe scale. Less than half of patients had the pain relief. Then, it was observed there was not coherence between the pain intensity and the analgesic it was used. To solve or relieve this kind of problems is necessary a permanent education to the health professionals who works in this area
Resumo:
Quasi-experimental study, with prospective data, comparative with quantitative approach, performed in a reference hospital, aiming to identify the effectiveness of the Numerical Rating Scale (NRS) and McGill Pain Questionnaire, used simultaneously, to evaluate a group of patients with oncologic pain (Experimental Group); to identify the effectiveness of the Numerical Rating Scale (NRS) to evaluate a group of patients with oncologic pain (Control Group); to identify the resolution of pain according to prescribed medication, considering the result of the rating scales, and to compare it between the two groups of patients in the study. The population consisted of 100 patients, with both the experimental and control groups being composed of 50 people, with data collected from February to April 2010. The results show that in the experimental group, 32% of the patients were aged 60 to 69, 80% were female; 30% had a primary tumor in the breast, 58% had metastasis, and on 70% the disease was localized. In the first pain evaluation, 26% identified it as light; 46%, moderate; and 28%, severe; with an average of 5.50. In the second pain evaluation, 2% reported no pain; 70%, light; 26%, moderate. and 2%, severe, with an average of 3.30. On those with moderate pain, 60% used non-opioid medicine, 25% under severe pain were medicated with non-opioids and 41.67% with weak opioids. Regarding the Pain Management Index (PMI), 44.0% were rated as "-1". In the control group, 28% were aged 40 to 49, and 54% were male; 20% had primary tumor in the breast and genital-urinary system, consecutively; 56% presented metastasis; on 64% the disease was localized. In the first pain evaluation, 14% considered it light; 42%, moderate; and 44%, severe; with an average of 6.26. In the second pain evaluation, 18% did not signal pain; on 38% pain was light; 40%, moderate; and 4%, severe; with an average of 3.0. Regarding medicine therapy, 71.43% with moderate pain used non-opioids, 22.73% with severe pain used non-opioids and 27.27% weak opioids. Considering PMI, 42% were rated "-1"; and 42%, rated "0". We conclude that, despite the importance of pain as the 5th vital sign, it is still under-identified and under-treated by professionals. Nevertheless, studied oncologic patients had a tendency to report pain more easily when evaluated with the NRS instrument than with the combined use of NRS and MPQ. We believe, however, that the combination of these two instruments represents a more effective evaluation of pain, as it allows comprehension of its quantitative and qualitative aspects. We recommend, however, the replication of this study on a larger population, for a longer span of time, and consequently generating more evaluations, so this can confirm or deny the hypothesis that NRS and MPQ can, together, better evaluate pain on the oncologic patient
Resumo:
The incessant search if nurse for qualify nursing care makes the Nursing Assistance Systematization, a current topic of discussion throughout the country, not only in order to comply the legal requirements of their practice, but especially by the expected benefits of its application. In this meaning, this research had a qualitative approach, developed for a way of research-action. The general purpose was to analyze the change in the nursing practices in a pediatric teaching hospital, based on construction and implementation of Nursing Assistance Systematization by the nursing team. The results had the thematic analysis of Paulo Freire and were shown in the form of reports. To achieve these purposes, it began by steps pre-trial, to review the charts of the institution and an approach with the managers. In the situational diagnosis of nursing practices without the systematization followed by applying a questionnaire with a nursing team and a focal group with nurses. These ways supported the implementation stage of the Nursing Assistance Systematization which developed actions associate such as focal group with the nurses about the nursing history, capacity with the nursing team about the Nursing Assistance Systematization, development, application and reworking of printed, and discussions in the small groups. The evaluations of the changes after the actions of the research occurred through individual interview with the nurses, to check the results. The charts review confirmed the deficit in the records performed by the nurse on the chart, which reinforced the need for implementation of Nursing Assistance Systematization, an argument used on the meeting with the managers, who promptly agree with the search. The questionnaire and the focal group with the nurses reveal a process of nursing work without systematization, showing gaps in practices, but also obtained relate of expectations of improvements in quality of care as of Nursing Assistance Systematization, furnishing data to the development of ways following-up. The prints were gradually used and modified as the team understood the Nursing Assistance Systematization and its purposes through capacity course. The final evaluation pointed to the partial implementation of the stages of Nursing Assistance Systematization had been institutionalized at the history and the development of nursing, beyond difficulties with diagnosis and prescription of nursing, in later representing a paradigm shift. This search collaborated to change the view about the Nursing Assistance Systematization by nursing team at the institution had been revealed through introduction of new practices in the process of nursing work, as examination of physical exam of the patient, the interview in the admission of customers on service and the daily monitoring by nursing through development of nursing. Before addition, it was noted which the purposes of this search were achieved, since were analyzed the changes in the nursing practices with the systematization. The research-action achieved proposes of the involvement of nursing team in changing their practices. This search contributed to the implementation of the Nursing Assistance Systematization in a pediatric teaching hospital and showed which is possible to seek resolution of problems when the objective is of the group and gave access for further searches within this theme
Resumo:
The counseling on HIV/Aids consists in a prevention strategy that contributes to increase the diagnosis of HIV and start earlier the treatment. The counseling has as pillars the emotional and educational support, risks evaluation that aim at the adoption of safe practices and the individual s responsibility for his own health. To accomplish these results, it is necessary that health workers understand counseling as a unique educational moment that stimulates the user s critical-reflection when it comes to his role as an active subject in this process. This study aimed to analyze the counseling on HIV/Aids conducted by the professionals of the Testing and Counseling Center (CTA), based on the educational perspective of Paulo Freire . This is a descriptive qualitative study with a critical reflexive design based on the principles of Action-Science. All the professionals acting as counselors in the Joao Pessoa, PB CTA, eight in total, took part in the study. Data were collected during the month of March, 2011, through non participative observation and semi-structured interviews with a critical-reflexive focus, analyzed according to the tenets of the critical-reflexive methodology, and discussed taking into consideration the Paulo Freire s pedagogy and pertinent literature. It was observed that most of the professionals expressed the work philosophy of CTA as the diagnosis and prevention of the disease, associated with the utilization and demonstration of condoms. However, upon observation of their counseling sessions, these ideas were not converted in actions. Educational themes were not covered and the condom wasn t offered at any time. The counseling actions focused on the provision of information and filling out the paper forms which are necessary for attendance. The sessions were conducted with brief dialogues and little opportunity for the users to expose or complement their thoughts and needs. The professionals mentioned as facilitating conditions for counseling, the team interaction and physical structure. The difficulties focused on the users low cognition, the large demand for attendance, aspects related to the service organization, and the counselors absences and delays. After reflecting about the actions observed in the counseling, the majority of professionals admitted the need to modify their practice in the incorporation of educational principles for the achievement of a broader prevention, and seemed to be willing to work in this perspective. In conclusion, although the counselors show ideas consistent with the purposes of CTA, these ideas are limited when it comes to the understanding of the meaning of prevention in HIV/Aids. Taking into consideration that they express a certain comprehension and act differently during the counseling, they demonstrate a lack of bond between the theories in use and the proposed ones, in accordance with the contribution of the action-science theory. The counseling, as an educative practice, doesn t materialize in the counseling itself and the orientation for reflection is not given during the attendance. These findings suggest the need to include the process of reflection in the execution of the actions of counseling, so that these practices are guided by reflexive practice, aiming at transforming the way of thinking and acting into a more educational perspective toward a more democratic and holistic assistance.
Resumo:
The nursing process (NP) it s the systematized way of offering humanized care with the objective of reaching the expected results. The concern of the health and education institutions of elaborating implementation strategies of it is growing. The objective of this research was to know the vision of the senior students of the nursing graduation courses from Natal/RN, about the teaching of the NP. It s about a descriptive and exploratory study of the qualitative and quantitative type, done in five teaching institutions of the undergraduate nursing course of the municipality of Natal- RN in 2011. The research was composed by 48 students of the last 2 years of the nursing course. The gathering of the data was done through an online survey with open and closed questions via SurveyMonkey. For the quantitative data it was used the descriptive statistics from Microsoft Office Excel and for the qualitative data the Content Analysis of Bardin. The results pointed a predominance of female students (81,25%) with an age between 21- 39 years old (75,00%) and in the last year of the course (62,50%). As the opinion of the students about the NP two categories emerged: 1) Nursing Process as grounded method in scientific knowledge and established in two stages; 2) Nursing Assistance Quality, with two subcategories: Nursing Process as Nursing Practice and Nursing Process as instrument of improvement of the aid quality and promotion of well-being. In relation to the tuition of the NP the students (45,83%) said that the knowledge on the subject of the instructor was good; 81,25% reported that the professors use a traditional teaching methodology with the problem solving components and 45,83% answered that is addressed in specific disciplines in an isolated way starting from the professional line. The phase of NP that the nursing students have more difficulties of learning and implementing, being mentioned 22 times (29,70%). In relation to the student s difficulties, in the fields of supervised internships, in applying the NP it was stated for 83,50% that the barriers were related to the non implementation of the practice, overwork and the lack of trust of the nurse in the NP. The teaching-care strategies described as the internship fields were: the training of nurses to be able to contribute with the University in the implementation of the service and teaching; and the need of the universities to focus, continuously throughout the course, the NP with the involvement and incentive of the instructors in this process. These results show that the NP for the nursing students is a work methodology of the profession that needs to be implemented effectively in the practical reality for its teaching to turn effective and for the future professionals to be able to bring real contributions in the achievement of systematized actions trying to improve the assistance quality and the nursing actions. It is expected that this study could help bringing some strategies to facilitate the merging between theory and practice in teaching the NP and stimulate a discussion about the topic at the Nursing Schools where the research was held together with the coordinators, instructors and students
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This work aims to "build" rostering urban bus crews to minimize the cost of overtime. For this purpose a mathematical model was developed based on case study in an urban transport company in the metropolitan region of Natal. This problem is usually known in the literature as the Crew Scheduling Problem (CSP) and classified as NP-hard. The mathematical programming takes into account constraints such as: completion of all trips, daily and maximum allowable range of home and / or food. We used the Xpress-MP software to implement and validate the proposed model. For the tested instances the application of the model allowed a reduction in overtime from 38% to 84%
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The locomotion is one of the most important capabilities developed by the animals, whose improvement is dependent on several neural centers, including the spinal cord. This activity promotes a lot of spinal modifications that enable it to adapt and improve their connections. This study aimed to observe the morphological changes occurring in the spinal cord after locomotor training in intact rats. For that we used male Wistar rats, which were submitted to locomotor training in wheel activity in protocols 1, 3 and 7 days (30min/day), and the results were compared to a control group not subjected to exercise. Coronal sections of 40 μm of the lumbosacral spinal cord were subjected to immunohistochemical techniques anti-Egr1, anti-NMDA and anti-SP, to characterize the spinal plasticity related to these substances. Egr1-immunoreactive cells were increased in all laminas, essentially in those more intensely activated by locomotion, laminas IV-X levels L4-S3. All observed sections expressed NMDA-immunoreactivity. Analysis of SP in the spinal dorsal horn resulted no significant variations of this neuropeptide related to locomotion. The results suggest that locomotor training provides synaptic plasticity similar to LTP in all laminas of the lumbosacral spinal cord, in different intensities. However, the SP appears do not participate of this process in the spinal dorsal horn. This work will contribute for consolidating and characterization of synaptic plasticity in the spinal cord
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To the vertebrates, maintain body balance against the gravitational field and be able to orient themselves in the environment are fundamental aspects for survival, in which the participation of vestibular system is essential. As part of this system, the vestibular nuclear complex is the first central station that, by integrating many information (visual, proprioceptive), and the vestibular, assumes the lead role in maintaining balance. In this study, the vestibular nuclear complex was evaluated in relation to its cytoarchitecture and neurochemical content of cells and axon terminals, through the techniques of Nissl staining and immunohistochemistry for neuronal specific nuclear protein (NeuN), glutamate (Glu), substance P (SP), choline acetyltransferase (ChAT) (enzyme that synthesizes acetylcholine-Ach) and glutamic acid decarboxylase (GAD) (enzyme that synthesizes gamma-amino butyric acid-GABA). The common marmoset (Callithrix jacchus) was used as experimental animal, which is a small primate native from the Atlantic Forest in the Brazilian Northeast. As results, the Nissl technique, complemented by immunohistochemistry for NeuN allowed to delineate the vestibular nucleus superior, lateral, medial and inferior (or descending) in the brain of the common marmoset. Neurons and terminals immunoreactive to Glu and ChAT and only immunoreactive terminals to SP and GAD were seen in all nuclei, although in varying density. This study confirms the presence in the vestibular nuclei of the common marmoset, of Glu and SP in terminals, probably from the first order neurons of vestibular ganglion, and of GABA in terminals, presumably from Purkinge cells of the cerebellum. Second-order neurons of the vestibular nuclei seem to use Glu and Ach as neurotransmitters, judging by their expressive presence in the cell bodies of these nuclei in common marmosets, as reported in other species
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In this study, two circadian related centres, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) were evaluated in respect to their cytoarchitecture, retinal afferents and chemical content of major cells and axon terminals with a tract tracer and immunohistochemical techniques in the rock cavy (Kerodon rupestris), a Brazilian caviidae rodent species. The rock cavy SCN is innervated in its ventral portion by terminals from the predominantly contralateral retina. It also contains neurophisin and vasoactive intestinal polypeptide immunoreactive cell bodies and neuropeptide Y and enkephalin immunopositive fibres and terminals and is marked by intense GFAP immunoreactivity. The IGL receives a predominantly contralateral retinal projection, contains neuropeptide Y and nitric oxide synthase producing neurons and enkephalin immunopositive terminals and is characterized by dense GFAP immunoreactivity. This is the first report examining the neural circadian system in a crepuscular rodent species for which circadian properties have been described. The results are discussed comparing with what has been described for other species and in the context of the functional significance of these centres
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In adolescents, who tend to sleep and wake-up later, the school schedule in the morning is associated with sleep advancement and shortening besides bedtime and wake-up time irregularity between week and weekend days. As a result, there is an increase in daytime sleepiness and a drop in cognitive performance that interfer in students performance in classroom. These consequences reinforce the need to evaluate alternatives that help the adolescent to adapt their sleep needs to the time of start of classes in the morning. Accordingly, the general aim of this study was to evaluate the effects of a sleep program education and sunlight exposure in early morning on sleep-wake cycle (SWC) and daytime sleepiness of adolescents. The students chronotype were evaluated by the Horne-Ostberg questionnaire and the health and usual sleep habits by "the health and the sleep questionnaire. The SWC patterns were assessed by sleep log, the daytime sleepiness by Karolinska Sleepiness Scale (KSS) and the alertness by the Psychomotor Vigilance Test (PVT). These parameters were compared before and after a sleep education program and before and during the sunlight exposure. The sleep program was effective in increasing sleep knowledge of adolescents, in promoting a reduction of bedtime and wake-up time irregularity and increasing the sleep duration in school days. The sunlight exposure effect was evaluated in the return to classes after vacation due to the difference in sleep patterns between school and vacation days. During the intervention week it was observed an advance of sleep schedules, an increase on sleep duration and alertness at the end of the morning. Assessed separately, sleep education and sunlight exposure should contribute to minimize adolescents partial sleep deprivation, but daytime sleepiness effect must be better investigated. These strategies should be used jointly by school members to improve health and performance of their students
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The primary and accessory optic systems comprise two set of retinorecipient neural clusters. In this study, these visual related centers in the rock cavy were evaluated by using the retinal innervations pattern and Nissl staining cytoarchigtecture. After unilateral intraocular injection of cholera toxin B subunit and immunohistochemical reaction of coronal and sagittal sections from the diencephalon and midbrain region of rock cavy. Three subcortical centres of primary visual system were identified, superior colliculus, lateral geniculate complex and pretectal complex. The lateral geniculate complex is formed by a series of nuclei receiving direct visual information from the retina, dorsal lateral geniculate nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus. The pretectal complex is formed by series of pretectal nuclei, medial pretectal nucleus, olivary pretectal nucleus, posterior pretectal nucleus, nucleus of the optic tract and anterior pretectal nucleus. In the accessory optic system, retinal terminals were observed in the dorsal terminal, lateral terminal and medial terminal nuclei as well as in the interstitial nucleus of the superior fasciculus, posterior fibres. All retinorecipient nuclei received bilateral input, with a contralateral predominance. This is the first study of this nature in the rock cavy and the results are compared with the data obtained for other species. The investigation represents a contribution to the knowledge regarding the organization of visual optic systems in relation to the biology of species.
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The circadian system consists of multiple oscillators organized hierarchically, with the suprachiasmatic nucleus (SCN) as the master oscillator to mammalians. There are lots of evidences that each SCN cell is an oscillator and that entrainment depends upon coupling degree between them. Knowledge of the mechanism of coupling between the SCN cells is essential for understanding entrainment and expression of circadian rhythms, and thus promote the development of new treatments for circadian rhythmicity disorders, which may cause various diseases. Some authors suggest that the dissociation model of circadian rhythm activity of rats under T22, period near the limit of synchronization, is a good model to induce internal desynchronization, and in this way, enhance knowledge about the coupling mechanism. So, in order to evaluate the pattern of the motor activity circadian rhythm of marmosets, Callithrix jacchus, in light-dark cycles at the lower limit of entrainment, two experiments were conducted: 1) 6 adult females were submitted to the LD symmetric cycles T21, T22 and T21.5 for 60, 35 and 48 days, respectively; 2) 4 male and 4 female adults were subjected to T21 for 24 days followed by 18 days of LL, and then back to T21 for 24 days followed by 14 days of LL. Vocalizations of all animals and motor activity of each one of them were continuously recorded throughout the experiments, but the vocalizations were recorded only in Experiment 1. Under the Ts shorter than 24 h, two simultaneous circadian components appeared in motor activity, one with the same period of LD cycle, named light-entrained component, and the other in free-running, named non-light-entrained component. Both components were displayed for all the animals in T21, five animals (83.3%) in T21.5 and two animals (33.3%) in T22. For vocalizations both components were observed under the three Ts. Due to the different characteristics of these components we suggest that dissociation is result of partial synchronization to the LD cycle, wherein at least one group oscillator is synchronized to the LD by relative coordination and masking processes, while at least another group of oscillators is in free-running, but also under the influence of masking by the LD. As the T21 h was the only cycle able to promote the emergence of both circadian components in circadian rhythms of all Callithrix jacchus, this was then considered the lower entrainment limit of LD cycle promoter of dissociation in circadian rhythmicity of this species, and then suggested as a non-human primate model for forced desynchronization