Temática das dissertações e teses em ciência da informação no Programa de Pós-Graduação em Ciências da Comunicação da USP

Estudo de natureza descritiva cujo objetivo foi traçar um panorama temático das dissertações de mestrado e teses de doutorado apresentadas ao Programa de Pós-graduação em Ciências da Comunicação Área de concentração: Ciência da Informação e Documentação da Escola de Comunicações e Artes da Universidade de São Paulo, no período de 1979 a 2002. O universo de estudo constituiu-se de 114 documentos (75 dissertações de mestrado e 39 teses de doutorado). As variáveis da produção analisada referiram-se à distribuição temporal, temáticas abordadas e sua relação com as linhas de pesquisa departamentais. As dissertações/teses foram agrupadas nas categorias da Lista de Cabeçalho de Assunto adotada pelo Library and Information Science Abstracts (LISA). Observou-se que a produção discente da pós-graduação manteve-se estável no período, com tendência a aumentar. Na análise temática, as categorias 19.0 Other Fringe Subjects [Outros Assuntos Correlatos] e 12.0 Bibliographc Records [Registro Bibliográfico] foram as mais abordadas, detendo respectivamente, 22,81% e 15,54% da produção. Foram identificados como temas de maior interesse para a elaboração dos trabalhos: ação cultural, sistemas e linguagens de indexação, materiais em C&T e medicina, bibliotecas públicas e meios de comunicação de massa. Contatou-se que as temáticas abordadas na produção refletem as características da área de concentração e das linhas de pesquisa.

Impact of tight glycemic control on cerebral glucose metabolism after severe brain injury: a microdialysis study.

OBJECTIVES: To analyze the effect of tight glycemic control with the use of intensive insulin therapy on cerebral glucose metabolism in patients with severe brain injury. DESIGN: Retrospective analysis of a prospective observational cohort. SETTING: University hospital neurologic intensive care unit. PATIENTS: Twenty patients (median age 59 yrs) monitored with cerebral microdialysis as part of their clinical care. INTERVENTIONS: Intensive insulin therapy (systemic glucose target: 4.4-6.7 mmol/L [80-120 mg/dL]). MEASUREMENTS AND MAIN RESULTS: Brain tissue markers of glucose metabolism (cerebral microdialysis glucose and lactate/pyruvate ratio) and systemic glucose were collected hourly. Systemic glucose levels were categorized as within the target "tight" (4.4-6.7 mmol/L [80-120 mg/dL]) vs. "intermediate" (6.8-10.0 mmol/L [121-180 mg/dL]) range. Brain energy crisis was defined as a cerebral microdialysis glucose <0.7 mmol/L with a lactate/pyruvate ratio >40. We analyzed 2131 cerebral microdialysis samples: tight systemic glucose levels were associated with a greater prevalence of low cerebral microdialysis glucose (65% vs. 36%, p < 0.01) and brain energy crisis (25% vs.17%, p < 0.01) than intermediate levels. Using multivariable analysis, and adjusting for intracranial pressure and cerebral perfusion pressure, systemic glucose concentration (adjusted odds ratio 1.23, 95% confidence interval [CI] 1.10-1.37, for each 1 mmol/L decrease, p < 0.001) and insulin dose (adjusted odds ratio 1.10, 95% CI 1.04-1.17, for each 1 U/hr increase, p = 0.02) independently predicted brain energy crisis. Cerebral microdialysis glucose was lower in nonsurvivors than in survivors (0.46 +/- 0.23 vs. 1.04 +/- 0.56 mmol/L, p < 0.05). Brain energy crisis was associated with increased mortality at hospital discharge (adjusted odds ratio 7.36, 95% CI 1.37-39.51, p = 0.02). CONCLUSIONS: In patients with severe brain injury, tight systemic glucose control is associated with reduced cerebral extracellular glucose availability and increased prevalence of brain energy crisis, which in turn correlates with increased mortality. Intensive insulin therapy may impair cerebral glucose metabolism after severe brain injury.

Pesquisa disciplinar do corpus documental das teses de doutorado do PPGCI-IBICT/UFRJ: aplicando princípios e categorias para estudo interdisciplinar da ciência da informação no Brasil

A partir do histórico da ciência da informação no Brasil, realizou-se estudo visando a investigar, mediante princípios e categorias, a relação das disciplinas com a ciência da informação. O modelo aplicado dividiu o corpus de 58 teses em três categorias: disciplinas como conjuntos distintos, já que os conceitos e métodos dessa categoria não são suficientes para formalizar um quadro interdisciplinar. A segunda pela interação dos conceitos abordados, com encadeamento das questões colocadas pelas disciplinas na busca de solução para o problema proposto. A terceira remete à integração entre a disciplina e a ciência da informação, apresentando uma linguagem comum. O resultado do estudo visa a contribuir para a criação de um método de pesquisa interdisciplinar para a pós-graduação brasileira.

Changes in cerebral compartmental compliances during mild hypocapnia in patients with traumatic brain injury.

The benefit of induced hyperventilation for intracranial pressure (ICP) control after severe traumatic brain injury (TBI) is controversial. In this study, we investigated the impact of early and sustained hyperventilation on compliances of the cerebral arteries and of the cerebrospinal (CSF) compartment during mild hyperventilation in severe TBI patients. We included 27 severe TBI patients (mean 39.5 ± 3.4 years, 6 women) in whom an increase in ventilation (20% increase in respiratory minute volume) was performed during 50 min as part of a standard clinical CO(2) reactivity test. Using a new mathematical model, cerebral arterial compliance (Ca) and CSF compartment compliance (Ci) were calculated based on the analysis of ICP, arterial blood pressure, and cerebral blood flow velocity waveforms. Hyperventilation initially induced a reduction in ICP (17.5 ± 6.6 vs. 13.9 ± 6.2 mmHg; p < 0.001), which correlated with an increase in Ci (r(2) = 0.213; p = 0.015). Concomitantly, the reduction in cerebral blood flow velocities (CBFV, 74.6 ± 27.0 vs. 62.9 ± 22.9 cm/sec; p < 0.001) marginally correlated with the reduction in Ca (r(2) = 0.209; p = 0.017). During sustained hyperventilation, ICP increased (13.9 ± 6.2 vs. 15.3 ± 6.4 mmHg; p < 0.001), which correlated with a reduction in Ci (r(2) = 0.297; p = 0.003), but no significant changes in Ca were found during that period. The early reduction in Ca persisted irrespective of the duration of hyperventilation, which may contribute to the lack of clinical benefit of hyperventilation after TBI. Further studies are needed to determine whether monitoring of arterial and CSF compartment compliances may detect and prevent an adverse ischemic event during hyperventilation.

Parálisis cerebral. Tratamiento ortopodológico

Después de varios años de experiencia en la aplicación de las férulas estabilizadoras del sistema aquileocalcáneo plantar FESAP) en pacientes con parálisis cerebral, creemos que deberían ser el tratamiento ortopodológico de elección del pie equino en niños con miopatías y lesiones neurológlcas de la unidad motora, del sistema piramidal o extrapiramidal, tanto por su perfecta adaptación a la morfología de la extremidad inferior como por sus caracteristicas funcionales y sus acciones fisio1ógicas y terapéuticas.

Neuronal calcium channel mutation in a patient with congenital ataxia and attacks of hemiplegic migraine with cerebral edema

Background: Familial Hemiplegic Migraine (FHM), characterized by a prolonged unilateral hemiparesis, mainly results from mutations in the alpha-1a subunit of the calcium channel gene CACNA1A that can also cause two other dominantly inherited neurological disorders, Episodic Ataxia type 2 (EA2, with sometimes migrainous headaches) and Spinocerebellar Ataxia type 6 (SCA6, late-onset and progressive). A same mutation can have different clinical expression in a family (hemiplegic migraine, migraine-coma, cerebellar ataxia). CACNA1A mutations in FHM are usually missense, leading to gain-of-function, while truncating mutations leading to loss-of-function are usually associated with EA2. Case report: This 9-year-old girl was seen as a baby for hypotonia and transient vertical nystagmus. Her first brain MRI was normal. She evolved as a congenital ataxia, but since the age of two, she had attacks of coma, hemiparesis (either side), partial seizures, dystonic movements and fever. Attacks were initially triggered by minor head bumps, subsequently spontaneous. Brain MRIs in the acute stage always showed transient unilateral hemisphere swelling. Follow-up images revealed atrophic lesions in the temporo-occipital regions and cerebellar atrophy. A prophylactic trial with flunarizine was ineffective. Acetazolamide was recently introduced. Methods: Since our patient shared features of both FHM and EA2, we studied the CACNA1A gene by direct sequencing in the patient's and parents' DNA. Results: We identified an unreported de novo heterozygous deletion of three base pairs (c.4503_4505delCTT) predicting the deletion of one amino acid (p.Phe1502del). The CACNA1A protein contains 4 domains, each formed by six transmembrane segments. The deletion is located in a highly conserved region in segment 6 (S6) of the third domain. Mutations in S6 segments of calcium channels change single-channel conductance and channel selectivity, most resulting in loss-of-function. Outlook: In vitro expression studies of the identified mutation are underway, aiming at understanding its functional consequences and finding an efficient treatment.

Dominància i ocupació de l'espai en grups de primats no-humans: un model basat en conducta adaptativa

L'estructura jeràrquica és una de les característiques fonamentals de les societats de primats, que condiciona en gran mesura el comportament dels individus que conviuen al grup, però quines lleis regeixen la formació i l'estructura d'aquestes jerarquies?, per què en determinats grups els subjectes més dominants se situen al centre del grup i en altres de la mateixa espècie no? En el camp de la conducta animal s"han proposat múltiples hipòtesis però cap totalment satisfactòria, ja que a causa de les múltiples variables que hi influeixen és difícil desenvolupar una teoria que expliqui tota la complexitat que s"observa empíricament. La nostra proposta d"estudi es basa en l"enfocament de la modelització de la conducta adaptativa, la qual ens permet, mitjançant la simulació informàtica, implementar moltes de les variables que autors com Gust (1995), Koenig (2001) i Barta & Giraldeau (1998) han considerat importants per a l"estructura de formacions jeràrquiques en primats. Seguint el model proposat per Hemelrijk (1998), hem programat un simulador basat en agents, en el qual les regles de conducta implementades fan emergir estructures jeràrquiques complexes. En una primera fase de la investigació, que es desenvolupa en el present article, hem replicat els estudis de Hemelrijk (1996). Com els nostres resultats coincideixen amb els obtinguts per Hemelrijk, en posteriors treballs implementarem noves variables al nostre model.

Excitotoxicity-induced endocytosis confers drug targeting in cerebral ischemia.

OBJECTIVE: Targeting neuroprotectants specifically to the cells that need them is a major goal in biomedical research. Many peptidic protectants contain an active sequence linked to a carrier such as the transactivator of transcription (TAT) transduction sequence, and here we test the hypothesis that TAT-linked peptides are selectively endocytosed into neurons stressed by excitotoxicity and focal cerebral ischemia. METHODS: In vivo experiments involved intracerebroventricular injection of TAT peptides or conventional tracers (peroxidase, fluorescein isothiocyanate-dextran) in young rats exposed to occlusion of the middle cerebral artery at postnatal day 12. Cellular mechanisms of uptake were analyzed in dissociated cortical neuronal cultures. RESULTS: In both models, all tracers were taken up selectively into stressed neurons by endocytosis. In the in vivo model, this was neuron specific and limited to the ischemic area, where the neurons displayed enhanced immunolabeling for early endosomal antigen-1 and clathrin. The highly efficient uptake of TAT peptides occurred by the same selective mechanism as for conventional tracers. All tracers were targeted to the nucleus and cytoplasm of neurons that appeared viable, although ultimately destined to die. In dissociated cortical neuronal cultures, an excitotoxic dose of N-methyl-D-aspartate induced a similar endocytosis. It was 100 times more efficient with TAT peptides than with dextran, because the former bound to heparan sulfate proteoglycans at the cell surface, but it depended on dynamin and clathrin in both cases. INTERPRETATION: Excitotoxicity-induced endocytosis is the main entry route for protective TAT peptides and targets selectively the neurons that need to be protected.

El paciente con parálisis cerebral y su tratamiento odontoestomatológico

En el presente trabajo, se explican las características generales y odontoestomatológicas así como los tratamientos necesarios de los pacientes afectos de parálisis cerebral

Continuous determination of optimal cerebral perfusion pressure in traumatic brain injury.

OBJECTIVES: We have sought to develop an automated methodology for the continuous updating of optimal cerebral perfusion pressure (CPPopt) for patients after severe traumatic head injury, using continuous monitoring of cerebrovascular pressure reactivity. We then validated the CPPopt algorithm by determining the association between outcome and the deviation of actual CPP from CPPopt. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Neurosciences critical care unit of a university hospital. PATIENTS: A total of 327 traumatic head-injury patients admitted between 2003 and 2009 with continuous monitoring of arterial blood pressure and intracranial pressure. MEASUREMENTS AND MAIN RESULTS: Arterial blood pressure, intracranial pressure, and CPP were continuously recorded, and pressure reactivity index was calculated online. Outcome was assessed at 6 months. An automated curve fitting method was applied to determine CPP at the minimum value for pressure reactivity index (CPPopt). A time trend of CPPopt was created using a moving 4-hr window, updated every minute. Identification of CPPopt was, on average, feasible during 55% of the whole recording period. Patient outcome correlated with the continuously updated difference between median CPP and CPPopt (chi-square=45, p<.001; outcome dichotomized into fatal and nonfatal). Mortality was associated with relative "hypoperfusion" (CPP<CPPopt), severe disability with "hyperperfusion" (CPP>CPPopt), and favorable outcome was associated with smaller deviations of CPP from the individualized CPPopt. While deviations from global target CPP values of 60 mm Hg and 70 mm Hg were also related to outcome, these relationships were less robust. CONCLUSIONS: Real-time CPPopt could be identified during the recording time of majority of the patients. Patients with a median CPP close to CPPopt were more likely to have a favorable outcome than those in whom median CPP was widely different from CPPopt. Deviations from individualized CPPopt were more predictive of outcome than deviations from a common target CPP. CPP management to optimize cerebrovascular pressure reactivity should be the subject of future clinical trial in severe traumatic head-injury patients.

Cerebral perfusion CT in the evaluation of children with severe head trauma : 12.06

Purpose: To assess the value of cerebral perfusion CT (PCT) in children with traumatic brain injury in prediciting their consecutive clinical outcome. Materials and methods: Twelve paediatric patients with acute traumatic brain injury underwent cerebral CT coupled with PCT during their admission at the emergency room (ER). PCT maps were reviewed for mean transit time (MTT), regional cerebral blood flow (rCBF) and regional cerebral blood volume (rCBV) abnormalities. PCT results were compared to short- and mid-term clinical outcome. Results: 3 patients with low Glasgow Coma Scale (GCS) (98) and bad clinical outcome showed an increased MTT and decreased rCBV and rCBF. 5 patients with low GCS and good clinical outcome showed an increased MTT without abnormalities of rCBV and rCBF. In patients with GCS 08 and good outcome, PCT maps were normal in 2 cases; transient PCT abnormalities were identified in one case with an embedded fracture of the skull and in one case with an epileptic seizure. Conclusion: Cerebral PCT can identify diffuse abnormalities of cerebral perfusion in children with traumatic brain injury showing a low initial GCS and a bad outcome. PCT can be a valuable tool to predict the severity of the prognosis of these patients as soon as they are evaluated by CT-scan during their admission at the ER.

Single spin-echo T 2 relaxation times of cerebral metabolites at 14.1 T in the in vivo rat brain.

OBJECT: To determine the single spin-echo T 2 relaxation times of uncoupled and J-coupled metabolites in rat brain in vivo at 14.1 T and to compare these results with those previously obtained at 9.4 T. MATERIALS AND METHODS: Measurements were performed on five rats at 14.1 T using the SPECIAL sequence and TE-specific basis-sets for LCModel analysis. RESULTS AND CONCLUSION: The T 2 of singlets ranged from 98 to 148 ms and T 2 of J-coupled metabolites ranged from 72 ms (glutamate) to 97 ms (myo-inositol). When comparing the T 2s of the metabolites measured at 14.1 T with those previously measured at 9.4 T, a decreasing trend was found (p < 0.0001). We conclude that the modest shortening of T 2 at 14.1 T has a negligible impact on the sensitivity of the (1)H MRS when performed at TE shorter than 10 ms.

Use of a dynamic foot pressure index to monitor the effects of treatment for equinus gait in children with cerebral palsy.

The purpose of this study is to introduce and describe a newly developed index using foot pressure analysis to quantify the degree of equinus gait in children with cerebral palsy before and after injection with botulinum toxin. Data were captured preinjection and 12 weeks postinjection. Ten children aged 2(1/2) to 6(1/2) years took part (5 boys and 5 girls). Three of them had a diagnosis of spastic diplegia and 7 of congenital hemiplegia. In total, 13 limbs were analyzed. After orientation and segmentation of raw pedobarographic data, we determined a dynamic foot pressure index graded 0 to 100 that quantified the relative degree of heel and forefoot contact during stance. These data were correlated (Pearson correlation) with clinical measurements of dorsiflexion at the ankle (on a slow and fast stretch) and video observation (using the Observational Gait Scale). Pedobarograph data were strongly correlated with both the Observational Gait Scale scores (R = 0.79, P < 0.005) and clinical measurements of dorsiflexion on a fast stretch, which is reflective of spasticity (R = 0.70, P < 0.005). We demonstrated the index's sensitivity in detecting changes in spasticity and good correlation with video observations seems to indicate this technique's potential validity. When manipulated and segmented appropriately, and with the development of a simple ordinal index, we found that foot pressure data provided a useful tool in tracking changes in patients with spastic equinus.