Encoding mechanisms based on fast oscillations in the retina of the cat and their dependencies on anesthesia

Processing in the visual system starts in the retina. Its complex network of cells with different properties enables for parallel encoding and transmission of visual information to the lateral geniculate nucleus (LGN) and to the cortex. In the retina, it has been shown that responses are often accompanied by fast synchronous oscillations (30 - 90 Hz) in a stimulus-dependent manner. Studies in the frog, rabbit, cat and monkey, have shown strong oscillatory responses to large stimuli which probably encode global stimulus properties, such as size and continuity (Neuenschwander and Singer, 1996; Ishikane et al., 2005). Moreover, simultaneous recordings from different levels in the visual system have demonstrated that the oscillatory patterning of retinal ganglion cell responses are transmitted to the cortex via the LGN (Castelo-Branco et al., 1998). Overall these results suggest that feedforward synchronous oscillations contribute to visual encoding. In the present study on the LGN of the anesthetized cat, we further investigate the role of retinal oscillations in visual processing by applying complex stimuli, such as natural visual scenes, light spots of varying size and contrast, and flickering checkerboards. This is a necessary step for understanding encoding mechanisms in more naturalistic conditions, as currently most data on retinal oscillations have been limited to simple, flashed and stationary stimuli. Correlation analysis of spiking responses confirmed previous results showing that oscillatory responses in the retina (observed here from the LGN responses) largely depend on the size and stationarity of the stimulus. For natural scenes (gray-level and binary movies) oscillations appeared only for brief moments probably when receptive fields were dominated by large continuous, flat-contrast surfaces. Moreover, oscillatory responses to a circle stimulus could be broken with an annular mask indicating that synchronization arises from relatively local interactions among populations of activated cells in the retina. A surprising finding in this study was that retinal oscillations are highly dependent on halothane anesthesia levels. In the absence of halothane, oscillatory activity vanished independent of the characteristics of the stimuli. The same results were obtained for isoflurane, which has similar pharmacological properties. These new and unexpected findings question whether feedfoward oscillations in the early visual system are simply due to an imbalance between excitation and inhibition in the retinal networks generated by the halogenated anesthetics. Further studies in awake behaving animals are necessary to extend these conclusions

Applicability of non-pharmacological strategies for pain relief in parturient: integrative review

MORAES, Maísa Suares Teixeira; ROLIM, Lariane Thays Albuquerque; ENDERS, Bertha Cruz; FARIAS, Glaucea Maciel de; DAVIM, Rejane Marie Barbosa. Applicability of non-pharmacological strategies for pain relief in parturient: integrative review. Revista de Enfermagem UFPE on line, v.4, n.especial, p.131-136, May/June 2010. Disponivel em:< http://www.ufpe.br/revistaenfermagem/index.php/revista/>.

Effects of the basic fibroblast growth factor and its anti-factor in the healing and collagen maturation of infected skin wound

PURPOSE: The infection is one of the main factors that affect the physiological evolution of the surgical wounds. The aim of this work is to evaluate the effects of fibroblast growth factor (FGFâ) and anti-FGFâ in the healing, synthesis and maturation of collagen when topically used on infected skin wounds of rats. METHODS: An experimental study was perfomed in 60 male Wistar rats. All animals were divided in two groups (A and B). Each group was divided in three subgroups A1, B1; A2, B2 and A3, B3. After anesthesia with pentobarbital, two open squared wounds (1cm2), 4cm distant to each other, were done in the dorsal skin of all the rats. In group A (n=30) the wounds were contaminated with multibacterial standard solution, and in group B(n=30) the wounds were maintained sterile. These wounds were named F1 (for inflammation analysis) and F2 (for collagen study). The open wounds of A1 and B1 rats were topically treated with saline solution, A2 and B2 were treated with FGFâ and subgroups A3 and B3 were treated with FGFâ and anti-FGFâ. The rats were observed until complete epitelization of F2 wounds for determination of healing time and the expression of types I and III collagen, using Picro Sirius Red staining. Inflammatory reaction in F1 wounds was studied using hematoxilineosin staining. The three variable was measured by the Image Pro-Plus Média Cybernetics software. The statistical analysis was performed by ANOVA and Tukey test, considering p<0.05 as significant. RESULTS: It was observed that infection retarded significantly (p<0.05) the time of wound scarring and the topical application of FCFb reverted the inhibition of healing caused by bacteria. The inflammatory reaction was greater in the subgroup B2 than in B1 and A3, and the difference was significant (p<0.05). It was observed greater expression of type I collagen in all the subgroups treated with FCFb, when compared with the untreated subgroups. Type III collagen was significantly decreased in wounds of B3 rats, comparing to the other subgroups. CONCLUSIONS: The FCFb accelerated the healing of open infected wounds and contributed with maturation of collagen, enhancing the type I collagen density. The anti-FCFb antibody was able to attenuate the production of both type I and III collagen

Influence of laparoscopy and laparotomy on gasometry, leukocytes and cytokines in a rat abdominal sepsis model

Laparoscopic surgery is associated with reduced surgical trauma, and less acute phase response, as compared with open surgery. Cytokines are important regulators of the biological response to surgical and anesthetic stress. The aim of this study was to determine if CO2 pneumoperitoneum would change cytokine expression, gas parameters and leukocyte count in septic rats. Methods: Wistar rats were randomly assigned to five groups: control (anesthesia only), laparotomy, CO2 pneumoperitoneum, cecum ligation and puncture by laparotomy, and laparoscopic cecum ligation and puncture. After 30 min of the procedures, arterial blood samples were obtained to determine leukocytes subpopulations by hemocytometer. TNFα, IL-1β, IL-6 were determined in intraperitoneal fluid (by ELISA). Gas parameters were measured on arterial blood, intraperitoneal and subperitoneal exsudates. Results: Peritoneal TNFα, IL-1β and IL-6 concentrations were lower in pneumoperitoneum rats than in all other groups (p<0.05). TNFα, IL-1β and IL-6 expression was lower in the laparoscopic than in laparotomic sepsis (p<0.05). Rats from laparoscopic cecum ligation and puncture group developed significant hypercarbic acidosis in blood and subperitoneal fluid when compared to open procedure group. Total white blood cells and lymphocytes were significantly lower in laparoscopic cecum ligation and puncture rats than in the laparotomic (p<0.01). Nevertheless, the laparotomic cecum ligation rats had a significant increase in blood neutrophils and eosinophils when compared with controls (p<0.05). Conclusions: This study demonstrates that the CO2 pneumoperitoneum reduced the inflammatory response in an animal model of peritonitis with respect to intraperitoneal cytokines, white blood cell count and clinical correlates of sepsis. The pneumoperitoneum produced hypercarbic acidosis in septic animals

Redução da morbi-mortalidade na síndrome de hellp completa com o uso de altas doses de dexametasona

Objective: To determine the clinical maternal and neonatal outcomes in HELLP syndrome patients treated with dexamethasone who either developed renal injury or renal insufficiency and to identify predictive values of urea and creatinine for the identification of subjects with HELLP syndrome at risk of developing renal insufficiency. Methods: Non-radomized intervention study of dexamethasone use in HELLP syndrome. A total of 62 patients were enrolled at Maternidade Escola Januário Cicco (MEJC). Patients received a total of 30 mg of dexamethasone IV, in three doses of 10 mg every 12 hours. A clinical and laboratory follow up were performed at 24, 48 and 72 hours. Patients were followed up to 6 months after delivery. Patients were grouped in accordance to renal function, i.e, normal and some type of renal lesion. Renal lesion was considered when creatinine was equal or greater than 1.3 mg/dl and diuresis less than 100 ml in 4 hours period and renal insufficiency was defined when dialysis was needed. Results: A total of 1230 patients with preeclampsia were admitted at MEJC. Of those 62 (5%) developed HELLP syndrome. There was no statistical difference in the groups with renal involvement or normal renal function with respect to the demographics, type of anesthesia used and delivery, and weight of the newborn. An improvement in the AST, ALT, LDH, haptoglobine, antithrombine, fibrinogenen and platelets was observed within 72 hours after dexamethosone use. There was a significant increase in the diuresis within the interval of 6 hours before the delivery and 24 hours after it. Of the 62 patients, 46 (74. 2%) had normal renal function and 16 (25.8%) evolved with renal lesion, with 5 (8.1%) needing dialysis. These 5 patients who received dialysis recovered the xi renal function. The delay in administering dexamethasone increased in 4.6% the risk of development of renal insufficiency. Patients with renal insufficiency had received significantly more blood products than subjects without renal lesion (p=0.03). Diuresis, leukocytes, uric acid, urea, creatinine were significantly different between the groups with normal renal function, renal lesion and renal insufficiency. The levels of creatinine 1.2mg/dl and uric acid 51mg/dl, at admission are predictive of subjects who will evolve with renal lesion (p<0.001). Maternal mortality was 3.2%. None of the subjects with renal insufficiency evolved with chronic renal disease. Conclusions: Dexamethasone in patients with HELLP syndrome seems to reduce significantly the hepatic microthrombosis and normalize hemostasis as seen by improvement of liver function. Renal injury can be considered, in HELLP syndrome, when creatinine levels are greater than 1.3 mg/dl and diuresis less than 100 ml/h in interval of 4 hours. The level of creatinine greater than 1.2 mg/dl and urea greater than 51mg/dl are predictive of subjects with HELLP syndrome who will develop renal injury. Patients who receive more red cell packs develop renal insufficiency. Finally, the delay in administering dexamethasone increases the risk of developing renal insufficiency

Biodistribuição do pertecnetato de sódio após cirurgia do Switch Duodenal

The biliopancretic diversion with duodenal switch is one of the mixing techniques used in the treatment of morbid obesity. The duodenal switch reduces the stomach capacity and leaves only 50-100 cm of small intestine for nutrition and absorption. The surgery produces hormonal, structural and biochemical changes, which can influence on the result of scintigraphic examinations in operated patients. With the objective of evaluate the postoperative biodistribution of sodium pertechnetate (Na99mTcO4) in brain, thyroid, heart, lung, liver, spleen, kidney, stomach, duodenum, pancreas, small intestine, bladder, muscle and bone of Wistar rats. The rats were randomly allocated into 3 groups of 7 rats each: the duodenal switch group (DS), the control group (C) and the sham group (S). They were operated under anesthesia and aseptic technique. In the tenth postoperative day, 0.1mL of sodium pertechnetate was injected via orbital plexus. After 30 min the animals were killed with overdose of anesthetic and samples of liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, bone and brain were harvested, washed with saline and weighed. The detention of radioactivity was made using the automatic Gamma Counter Wizard, PerkinElmer and the percentage of activity per gram of tissue (%ATI/g) was calculated. There was no early or late mortality in either rats groups. The values of percent radioactivity per gram of tissue (%ATI/g), showed no significant difference in liver, stomach, small bowel, duodenum, kidney, heart, bladder, bone and brain, when compared the DS rats with sham and controls rats. A postoperative significant increase in mean %ATI/g levels was observed in spleen, pancreas and muscle in group DS rats, as compared to group S and C rats (p<0.05). In the lung there was an increase and in thyroid a decrease in mean %ATI/g of DS rats, when compared to sham rats (p>0.05). In conclusion, the biliopancreatic diversion with duodenal switch in rats modified the biodistribution of sodium pertechnetate in thyroid, lung, pancreas, spleen and muscle. The study had the participation of the departments and laboratories researches, as Nucleus of Experimental Surgery, Department of Surgery, Laboratory of Radiobiology, Department of Pathology and Service of Nuclear Medicine, certifying the character of a multidisciplinary research

Influência da laparoscopia e da laparotomia na gasometria, leucometria diferencial e citocinas em modelo de sepse abdominal em ratos

Laparoscopic surgery is associated with reduced surgical trauma, and less acute phase response, as compared with open surgery. Cytokines are important regulators of the biological response to surgical and anesthetic stress. The aim of this study was to determine if CO2 pneumoperitoneum would change cytokine expression, gas parameters and leukocyte count in septic rats. Methods: Wistar rats were randomly assigned to five groups: control (anesthesia only), laparotomy, CO2 pneumoperitoneum, cecum ligation and puncture by laparotomy, and laparoscopic cecum ligation and puncture. After 30 min of the procedures, arterial blood samples were obtained to determine leukocytes subpopulations by hemocytometer. TNFα, IL-1β, IL-6 were determined in intraperitoneal fluid (by ELISA). Gas parameters were measured on arterial blood, intraperitoneal and subperitoneal exsudates. Results: Peritoneal TNFα, IL-1β and IL-6 concentrations were lower in pneumoperitoneum rats than in all other groups (p<0.05). TNFα, IL-1β and IL-6 expression was lower in the laparoscopic than in laparotomic sepsis (p<0.05). Rats from laparoscopic cecum ligation and puncture group developed significant hypercarbic acidosis in blood and subperitoneal fluid when compared to open procedure group. Total white blood cells and lymphocytes were significantly lower in laparoscopic cecum ligation and puncture rats than in the laparotomic (p<0.01). Nevertheless, the laparotomic cecum ligation rats had a significant increase in blood neutrophils and eosinophils when compared with controls (p<0.05). Conclusions: This study demonstrates that the CO2 pneumoperitoneum reduced the inflammatory and immune response in an animal model of peritonitis with respect to intraperitoneal cytokines, white blood cell count and clinical correlates of sepsis. The pneumoperitoneum produced hypercarbic acidosis in septic animals

O renascimento do parto e da (reinvenção da) emancipação social na blogosfera brasileira: contra o desperdício das experiências

The birth models of care are discussed, in the light of classical and contemporary social science theoretical background, emphasizing the humanistic model. The double spiral of the sociology of absences and the sociology of emergences is detailed, being based, on one hand, on the translation of experiences of knowledge, and, on the other, on the translation of experiences of information and communication, by revealing the movement articulated by Brazilian women on blogs that defend and bring into light initiatives aiming to recover natural and humanized birth. A cartography of the thematic ideas in birth literature is produced, resulting in the elaboration of a synthetic map on obstetric models of care in contemporaneity, pointing out the consequences of the obstetric model that has become hegemonic in contemporary societies, and comparing that model to others that work more efficaciously to mothers and babies. A symbolic cartography of the activism for humanizing birth on the Brazilian blogosphere is configured by the elaboration of an analytical map synthetizing the main mottos defended by the movement: Normal humanized birth; Against obstetrical violence; and Planned home birth. The superposition of the obstetric models of care s map and the rebirth of birth s analytical map indicates it is necessary to reinforce three main measures in order to make a paradigmatic turn in contemporary birth models of care possible: pave the way for the humanistic care of assistance in normal birth, by defending and highlighting practices and professionals that act in compliance with evidence based medicine, respecting the physiology of birth; denaturalize obstetric violence, by showing how routine procedures and interventions can be means of aggression, jeopardizing the autonomy, the protagonism and the respect towards women; and motivate initiatives of planned home birth, the best place for the occurrence of holistic experiences of birth. It is concluded that Internet tools have allowed a pioneer mobilization in respecting women s reproductive rights in Brazil and that the potential of the crowd s biopower that resides on the blogosphere can turn blogs into a hegemonic alternative way to reach more democratic forms of social organization. In that condition of being virtually hegemonic in contesting the established power, these blogs can be understood, therefore, as potentially great contra-hegemonic channels for the rebirth of birth and for the reinvention of social emancipation, as their author s articulate and organize themselves to strive against the waste of experience, trying to create reciprocal intelligibility amongst different experiences of world

Experienciando a ausência do companheiro nas consultas de pré-natal

This research aimed to understand pregnant general meaning about consort absence in prenatal care. It s an exploratory and descriptive qualitative approach, developed at Centro de Saúde de Jardim Lola, São Gonçalo do Amarante / RN. Participated in investigation 20 pregnant enrolled in prenatal program, their aged over 18 years, guidance of mental faculties and who survive together her partner. Data were collected from March to May 2009, through semi-structured interview. The analysis was processed according to grounded theory and symbolic interactionism as theoretical and methodological references. To support discussions were used literature findings involving political aspects of women humanization in health care and gender relations within family. Following footsteps of points it were adopted derived following sub categories: ¨Realizing involvement of consort during prenatal¨, ¨Expressing feelings during prenatal¨ and ¨Manifesting attitudes during prenatal period¨. These, when they had their properties and dimensions analyzed, resulted in the main category ¨ Experiencing absence of compeer in clinical prenatal¨. The construction of this theory leads to conclusion that women understand absence of her partner, attributing this to even work at the moment prenatal care or does not like to attend health institutions. However, this does not mean that his presence is dismissed, because desire to be with him in prenatal care was mentioned by most interviewees. So, partner absent at time, leads women to experience desires, feelings, attitudes, perceptions and expectations about studied phenomenon. This reality, induce that absence of them partner in prenatal care predisposes women to strengthening of discomforts arising from pregnancy and therefore goes against wellbeing of pregnant, and ensure the possibility of marital discord. This requires professional nursing measures to get in inclusion of partner in daily pre-natal care in humanization perspective.

Percepção do pai sobre sua presença no nascimento do filho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Nascimento de um filho :o significado para o pai

Qualitative study on the meaning of a child s birth to the father. Its general purpose was to comprehend the significance the man attaches to his child s birth and its specific objectives were to identify the man s feelings with regard to his child s birth as well as to verify his attitude toward a child s birth. The study was founded on the theoretical reference system about the man in the gravid-puerperal cycle and the humanization of the assistance. The data were obtained through semistructured interview performed with men accompanying their children s birth whose wives were in the immediate puerperium. This stage occurred in two maternity hospitals in Natal-RN, both of which adopt the principle of safe notherhood in the attendance of women in the process of parturition. The material apprehended from the statements was treated in conformity with the content analysis method in the mode of thematic analysis according to Bardin. Three thematic categories emerged from this process: the father s attitude toward his child s birth, the father s feelings in respect of his child s birth, and the informations received by the father in the course of his child s birth. The speech content was analyzed in accordance with the principles of symbolic interactionism according to Blumer. The results showed that the husbands interact with their respective wives and respond with attitudes of care, help, support, and encouragement within the principles of humanization intermingled with feelings of happiness, restlessness, and suffering leading them to appraise and exalt their consorts. Besides, we verified that the father s attitudes and feelings in the delivery room in the light of symbolic interactionism tend to be influenced by the interaction between him and the attending professionals

O cuidado humanístico como foco institucional: um estudo sobre empatia dos profissionais de saúde na área obstétrica

Empathy is a basic facilitating element of the therapeutic helping relationship and the humanization process in health care. The objectives of this study were to identify the empathy level of health professionals working in the obstetrical sector of a university hospital recognized for its humanistic care and the perceptions of the women under their care regarding the empathic behavior shown by these professionals during hospitalization. We conducted a quanti/qualitative study with 47 health professionals that worked in the obstetrical sector (13 obstetricians, 12 nurses, 22 nurse technicians) and an intentional sample of 101 women that received cared from these professionals during the study period. We collected data by means of the Jefferson Empathy Scale for Health Professioals (JEPS-HR) and the Patient´s Perception of Health Professional Empathy (PPHPE), and two additional open questions designed to obtain the subjective opinion about the empathic behavior during the care. We utilized thematic analysis for the data obtained through the open questions and descriptive and inferential statistics for the quantitative data. We identified five thematic categories that represent the aspects valued by the professionals in their relationship with the women under their care: emotional involvement, communication, warm environment, integral vision and technical/scientific knowledge. The mean score on the JEPS-HR reported for the health professionals was 120,40, being that the maximum possible was 140.The Cronbach Alpha for the JEPS-HR was 0,83, indicating an acceptable level of reliability for this population. We consider therefore, that these professionals presented an acceptable empathy level when compared to other populations observed with the JEPS-HR. The results also indicated that women had statistically significant (p ≤ 0,05) higher scores than men and that professionals with higher working hours tended to have lower scores in the empathy scale (r = -0,288; p ≤ 0,05). The analysis of the subjective responses of the women indicated that they were satisfied with the humanistic care provided by the professionals but they also point out the existence of some power relationships. There were no significant differences in the empathy level of the medical or nursing team perceived by the women who registered means of 41,90 and 41,20 respectively on the PPHPE. In view of these results and considering the relevance of the element of empathy for care based on humanistic values, we reiterate the importance of further in-service training for the health team of the hospital in focus, on the topics of empathy and global aspects of humanized care for the implementation of its mission

Revisitando o eletrocorticograma intra-operatório na epilepsia mesial do lobo temporal: relevância das oscilações de alta frequência

Epilepsies are neurological disorders characterized by recurrent and spontaneous seizures due to an abnormal electric activity in a brain network. The mesial temporal lobe epilepsy (MTLE) is the most prevalent type of epilepsy in adulthood, and it occurs frequently in association with hippocampal sclerosis. Unfortunately, not all patients benefit from pharmacological treatment (drug-resistant patients), and therefore become candidates for surgery, a procedure of high complexity and cost. Nowadays, the most common surgery is the anterior temporal lobectomy with selective amygdalohippocampectomy, a procedure standardized by anatomical markers. However, part of patients still present seizure after the procedure. Then, to increase the efficiency of this kind of procedure, it is fundamental to know the epileptic human brain in order to create new tools for auxiliary an individualized surgery procedure. The aim of this work was to identify and quantify the occurrence of epilepticform activity -such as interictal spikes (IS) and high frequency oscillations (HFO) - in electrocorticographic (ECoG) signals acutely recorded during the surgery procedure in drug-resistant patients with MTLE. The ECoG recording (32 channels at sample rate of 1 kHz) was performed in the surface of temporal lobe in three moments: without any cortical resection, after anterior temporal lobectomy and after amygdalohippocampectomy (mean duration of each record: 10 min; N = 17 patients; ethic approval #1038/03 in Research Ethic Committee of Federal University of São Paulo). The occurrence of IS and HFO was quantified automatically by MATLAB routines and validated manually. The events rate (number of events/channels) in each recording time was correlated with seizure control outcome. In 8 hours and 40 minutes of record, we identified 36,858 IS and 1.756 HFO. We observed that seizure-free outcome patients had more HFO rate before the resection than non-seizure free, however do not differentiate in relation of frequency, morphology and distribution of IS. The HFO rate in the first record was better than IS rate on prediction of seizure-free patients (IS: AUC = 57%, Sens = 70%, Spec = 71% vs HFO: AUC = 77%, Sens = 100%, Spec = 70%). We observed the same for the difference of the rate of pre and post-resection (IS: AUC = 54%, Sens = 60%, Spec = 71%; vs HFO: AUC = 84%, Sens = 100%, Spec = 80%). In this case, the algorithm identifies all seizure-free patients (N = 7) with two false positives. To conclude, we observed that the IS and HFO can be found in intra-operative ECoG record, despite the anesthesia and the short time of record. The possibility to classify the patients before any cortical resection suggest that ECoG can be important to decide the use of adjuvant pharmacological treatment or to change for tailored resection procedure. The mechanism responsible for this effect is still unknown, thus more studies are necessary to clarify the processes related to it

Adolescentes e jovens e suas bases de apoio :relações de amizade como suporte social no enfrentamento à violência

The purpose of this work is to map the family and community social supports for adolescents and young students from Bom Pastor Distric, West Zone of Natal/RN, as well as to describe how such resources are used by these individuaIs in that community. Social support refers not only to formal activities or organizations, but also to spontaneous or informal forms of support - friendship and solidarity nets available in the community, affective relations that are meaningful in the lives of children and young people. Our discussion is based on a research performed with 382 adolescents and young students from Jean Mermoz Public School (students from 5th to 11th grades, aged 13 to 14). We emphasized the situations of violence derived from family or community spheres faced by these students. In relation to this specific aspect, we observed the participants more frequently look for help from the informal social supports, mostly from their friends, which indicates that the formal ones are not considered to be effective instruments for social assistance. The search for informal social supports shows the relations informally established in the streets (for instance when they look for help from friends, rei atives or neighbors) have more effect and play an important role in which there are values and affections exchange. Thinking the strengthening of these social links is of extreme importance and leads to the weakening of the hegemonic logics focused on the production of subjects as private identities, and to the amplification of an ethics committed to the disassembly of a sociability anchored to fear, impotence, intolerance, discrimination, and reduction of spaces for circulating and confronting mechanisms of social exclusion. It is crucial that we concentrate our attention to building friendship as a system of reciprocity and affective exchanges, as a space for political actions and production of forms of lives that are potent against social anesthesia