Glasgow coma scale pupil score (GCS-P) and the hospital mortality in severe traumatic brain injury: analysis of 1,066 Brazilian patients.

BACKGROUND: Pupil reactivity and the Glasgow Coma Scale (GCS) score are the most clinically relevant information to predict the survival of traumatic brain injury (TBI) patients. OBJECTIVE: We evaluated the accuracy of the GCS-Pupil score (GCS-P) as a prognostic index to predict hospital mortality in Brazilian patients with severe TBI and compare it with a model combining GCS and pupil response with additional clinical and radiological prognostic factors. METHODS: Data from 1,066 patients with severe TBI from 5 prospective studies were analyzed. We determined the association between hospital mortality and the combination of GCS, pupil reactivity, age, glucose levels, cranial computed tomography (CT), or the GCS-P score by multivariate binary logistic regression. RESULTS: Eighty-five percent (n = 908) of patients were men. The mean age was 35 years old, and the overall hospital mortality was 32.8%. The area under the receiver operating characteristic curve (AUROC) was 0.73 (0.70-0.77) for the model using the GCS-P score and 0.80 (0.77-0.83) for the model including clinical and radiological variables. The GCS-P score showed similar accuracy in predicting the mortality reported for the patients with severe TBI derived from the International Mission for Prognosis and Clinical Trials in TBI (IMPACT) and the Corticosteroid Randomization After Significant Head Injury (CRASH) studies. CONCLUSION: Our results support the external validation of the GCS-P to predict hospital mortality following a severe TBI. The predictive value of the GCS-P for long-term mortality, functional, and neuropsychiatric outcomes in Brazilian patients with mild, moderate, and severe TBI deserves further investigation.

ANTECEDENTES: A reatividade pupilar e o escore da Escala de Coma de Glasgow (ECG) representam as informações clínicas mais relevantes para predizer a sobrevivência de pacientes com traumatismo cranioencefálico (TCE). OBJETIVO: Avaliar a acurácia da ECG com resposta pupilar (ECG-P) como índice prognóstico para predizer mortalidade hospitalar em pacientes brasileiros acometidos por TCE grave e compará-lo com um modelo combinando ECG e resposta pupilar com fatores prognósticos radiológicos. MéTODOS: Foram analisados dados de 1.066 pacientes com TCE grave de 5 estudos prospectivos. Foi determinada a associação entre mortalidade hospitalar e a combinação de ECG, reatividade pupilar, idade, níveis glicêmicos, tomografia computadorizada (TC) de crânio ou o escore ECG-P por regressão logística binária multivariada. RESULTADOS: Oitenta e cinco por cento (n = 908) dos pacientes eram homens. A média de idade foi de 35 anos e a mortalidade hospitalar geral foi de 32,8%. A AUROC (em português, Curva Característica de Operação do Receptor) foi de 0,73 (0,70­0,77) para o modelo utilizando o escore ECG-P e de 0,80 (0,77­0,83) para o modelo incluindo variáveis clínicas e radiológicas. O escore ECG-P mostrou acurácia semelhante na previsão da mortalidade relatada para pacientes com TCE grave derivados dos estudos International Mission for Prognosis and Clinical Trials in TBI (IMPACT, na sigla em inglês) e Corticosteroid Randomization After Significant Head Injury (CRASH, na sigla em inglês). CONCLUSãO: Nossos resultados apoiam a validação externa da ECG-P para prever a mortalidade hospitalar após um TCE grave. O valor preditivo da ECG-P para mortalidade a longo prazo, resultados funcionais e neuropsiquiátricos em pacientes brasileiros com TCE leve, moderado e grave precisam ser investigados.

Glasgow coma scale pupil score (GCS-P) and the hospital mortality in severe traumatic brain injury: analysis of 1,066 Brazilian patients / Escala de coma de Glasgow com resposta pupilar (ECC-P) e mortalidade hospitalar em traumatismo cranioencefálico grave: análise de 1.066 pacientes brasileiros

Abstract Background Pupil reactivity and the Glasgow Coma Scale (CCS) score are the most clinically relevant information to predict the survival of traumatic brain injury (TBI) patients. Objective We evaluated the accuracy of the CCS-Pupil score (CCS-P) as a prognostic index to predict hospital mortality in Brazilian patients with severe TBI and compare it with a model combining CCS and pupil response with additional clinical and radiological prognostic factors. Methods Data from 1,066 patients with severe TBI from 5 prospective studies were analyzed. We determined the association between hospital mortality and the combination of CCS, pupil reactivity, age, glucose levels, cranial computed tomography (CT), or the CCS-P score by multivariate binary logistic regression. Results Eighty-five percent (n = 908) of patients were men. The mean age was 35 years old, and the overall hospital mortality was 32.8%. The area under the receiver operating characteristic curve (AUROC) was 0.73 (0.70-0.77) for the model using the CCS-P score and 0.80 (0.77-0.83) for the model including clinical and radiological variables. The CCS-P score showed similar accuracy in predicting the mortality reported for the patients with severe TBI derived from the International Mission for Prognosis and Clinical Trials in TBI (IMPACT) and the Corticosteroid Randomization After Significant Head Injury (CRASH) studies. Conclusion Our results support the external validation of the CCS-P to predict hospital mortality following a severe TBI. The predictive value of the CCS-P for long-term mortality, functional, and neuropsychiatric outcomes in Brazilian patients with mild, moderate, and severe TBI deserves further investigation.

Resumo Antecedentes A reatividade pupilar e o escore da Escala de Coma de Glasgow (ECC) representam as informações clínicas mais relevantes para predizer a sobrevivência de pacientes com traumatismo cranioencefálico (TCE). Objetivo Avaliar a acurácia da ECC com resposta pupilar (ECC-P) como índice prognóstico para predizer mortalidade hospitalar em pacientes brasileiros acometidos por TCE grave e compará-lo com um modelo combinando ECC e resposta pupilar com fatores prognósticos radiológicos. Métodos Foram analisados dados de 1.066 pacientes com TCE grave de 5 estudos prospectivos. Foi determinada a associação entre mortalidade hospitalar e a combinação de ECC, reatividade pupilar, idade, níveis glicêmicos, tomografia computadorizada (TC) de crânio ou o escore ECC-P por regressão logística binária multivariada. Resultados Oitenta e cinco por cento (n = 908) dos pacientes eram homens. A média de idade foi de 35 anos e a mortalidade hospitalar geral foi de 32,8%. A AUROC (em português, Curva Característica de Operação do Receptor) foi de 0,73 (0,70-0,77) para o modelo utilizando o escore ECC-P e de 0,80 (0,77-0,83) para o modelo incluindo variáveis clínicas e radiológicas. O escore ECC-P mostrou acurácia semelhante na previsão da mortalidade relatada para pacientes com TCE grave derivados dos estudos International Mission for Prognosis and Clinical Trials in TBI (IMPACT, na sigla em inglês) e Corticosteroid Randomization After Significant Head Injury (CRASH, na sigla em inglês). Conclusão Nossos resultados apoiam a validação externa da ECC-P para prever a mortalidade hospitalar após um TCE grave. O valor preditivo da ECC-P para mortalidade a longo prazo, resultados funcionais e neuropsiquiátricos em pacientes brasileiros com TCE leve, moderado e grave precisam ser investigados.

Predicting the Adsorption of Amoxicillin and Ibuprofen on Chitosan and Graphene Oxide Materials: A Density Functional Theory Study.

The occurrence, persistence, and accumulation of antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) represent a new environmental problem due to their harmful effects on human and aquatic life. A suitable absorbent for a particular type of pollutant does not necessarily absorb other types of compounds, so knowing the compatibility between a particular pollutant and a potential absorbent before experimentation seems to be fundamental. In this work, the molecular interactions between some pharmaceuticals (amoxicillin, ibuprofen, and tetracycline derivatives) with two potential absorbers, chitosan and graphene oxide models (pyrene, GO-1, and coronene, GO-2), were studied using the ωB97X-D/6-311G(2d,p) level of theory. The energetic interaction order found was amoxicillin/chitosan > amoxicillin/GO-1 > amoxicillin/GO-2 > ibuprofen/chitosan > ibuprofen/GO-2 > ibuprofen/GO-1, the negative sign for the interaction energy in all complex formations confirms good compatibility, while the size of Eint between 24-34 kcal/mol indicates physisorption processes. Moreover, the free energies of complex formation were negative, confirming the spontaneity of the processes. The larger interaction of amoxicillin Gos, compared to ibuprofen Gos, is consistent with previously reported experimental results, demonstrating the exceptional predictability of these methods. The second-order perturbation theory analysis shows that the amoxicillin complexes are mainly driven by hydrogen bonds, while van der Waals interactions with chitosan and hydrophobic interactions with graphene oxides are modelled for the ibuprofen complexes. Energy decomposition analysis (EDA) shows that electrostatic energy is a major contributor to the stabilization energy in all cases. The results obtained in this work promote the use of graphene oxides and chitosan as potential adsorbents for the removal of these emerging pollutants from water.

Vibronics and plasmonics based graphene sensors.

A high sensitivity and selectivity sensor is proposed using graphene ribbons which are able to read molecular vibrations and molecular electrostatic potentials, acting as an amplifier and as a transducer converting molecular signals into current-voltage quantities of standard electronics. Two sensing mechanisms are used to demonstrate the concept using ab initio density functional methods. By using the terahertz region of the spectrum, we can characterize modes when single molecules are adsorbed on the ribbon surface. Characteristic modes can be obtained and used as fingerprints, which can be transduced into current by applying a voltage along the ribbons. On the other hand, the fully delocalized frontier molecular orbitals of graphene ribbons, commonly denominated plasmons in larger solid state structures, are extremely sensitive to any moiety approach; once plasmons are in contact with an "agent" (actually its molecular potential), the transport through the ribbons acting as electrodes catching the signals is strongly affected.

Switchable molecular conductivity.

We demonstrate the switchability of the molecular conductivity of a citrate. This was made possible through mechanical stretching of two conformers of such citrate capped on and linked between gold nanoparticles (AuNPs) self-assembled as a film. On the basis of experimental results, theoretical analysis was conducted using the density function theory and Green's function to study the electron flux in the backbone. We found that the molecular conductivity depended on the pathways of electrons that were controlled by the applied mechanical stress. Under stress, we could tune the conductivity up and down for as much as 10-fold. The mechanochemistry behind this phenomenon is an alternative branch of chemistry.

Mechanism of carbon nanotubes unzipping into graphene ribbons.

The fabrication of graphene nanoribbons from carbon nanotubes (CNTs) treated with potassium permanganate in a concentrated sulfuric acid solution has been reported by Kosynkin et al. [Nature (London) 458, 872 (2009)]. Here we report ab initio density functional theory calculations of such unzipping process. We find that the unzipping starts with the potassium permanganate attacking one of the internal C-C bonds of the CNT, stretching and breaking it. The created defect weakens neighboring bonds along the length of the CNT, making them energetically prone to be attacked too.

Light-activated molecular conductivity in the photoreactions of vitamin D3.

In this theoretical-experimental approach, we show using ab initio calculations behavior consistent with the activation of 7-dehydrocholesterol, provitamin D(3), as an initial reactant toward ultraviolet-activated reactions of vitamin D(3). We find using molecular orbital theory that a conformation between the provitamin and the vitamin shows higher conductance than those of the reactant and product. We also find experimental evidence of this electrical character by directly measuring current-voltage characteristics on irradiated and nonirradiated samples of the provitamin. The activation of the provitamin D(3) is characterized with an increase in current during the irradiation.

DNA origami impedance measurement at room temperature.

The frequency response of triangular DNA origami is obtained at room temperature. The sample shows a high impedance at low frequencies, e.g., at zero frequency 20 Gohms, which decreases almost linearly with the logarithm of the frequency reaching a low and flat value at 100 kHz where the impedance turns from capacitive to resistive, concluding that DNA can be used for transmission of signals at frequencies larger than 100 kHz. It is also found that characteristics of DNA cannot be completely disentangled from the characteristics of the substrate on which it is deposited, making the design of molecular circuits more challenging than the design of circuits with present lumped devices; this is a natural feature at the nanoscale.

Current-voltage-temperature characteristics of DNA origami.

The temperature dependences of the current-voltage characteristics of a sample of triangular DNA origami deposited in a 100 nm gap between platinum electrodes are measured using a probe station. Below 240 K, the sample shows high impedance, similar to that of the substrate. Near room temperature the current shows exponential behavior with respect to the inverse of temperature. Sweep times of 1 s do not yield a steady state; however sweep times of 450 s for the bias voltage secure a steady state. The thermionic emission and hopping conduction models yield similar barriers of approximately 0.7 eV at low voltages. For high voltages, the hopping conduction mechanism yields a barrier of 0.9 eV and the thermionic emission yields 1.1 eV. The experimental data set suggests that the dominant conduction mechanism is hopping in the range 280-320 K. The results are consistent with theoretical and experimental estimates of the barrier for related molecules.

Graphene terahertz generators for molecular circuits and sensors.

Using ab initio density functional theory methods, the optimized structure of the single-, double-, and triple-layered graphene nanoribbons with different stacking orders and edges is calculated along with their Raman spectrums. For each case studied, graphene is found to be a potential source of vibrational signals in the terahertz region of the spectrum when molecules or another layer are adsorbed in the surface; this effect is independent of the hydrogen presence at the edges, and the stacking order. The visible low-frequency modes increase with the addition of graphene layers, and the number of modes may be influenced by the type of edges. The monolayer shows better performance due to the lower number of vibrational modes. The nanoribbon with fewer modes at the terahertz range is used to show a potential application of graphene acting as a sensor of single molecules.

Impedance measurements on a DNA junction.

1 microm double-stranded DNA molecules are immobilized between pairs of gold and pairs of platinum microelectrodes with gaps of 0.4 and 1 microm, respectively, and their electrical characteristics are determined under the application of constant and sinusoidal bias voltages. Due to their extremely high impedance for constant voltage bias, the samples of DNA are excellent insulators; however, their impedances show strong frequency dependence in the range of 10 Hz-7.5 MHz. Favorable response in the gold electrodes is attributed to the higher ability of DNA molecules to bridge the narrower gold electrode gaps in contrast to that in the wider platinum junctions.

Nanomicrointerface to read molecular potentials into current-voltage based electronics.

Molecular potentials are unreadable and unaddressable by any present technology. It is known that the proper assembly of molecules can implement an entire numerical processing system based on digital or even analogical computation. In turn, the outputs of this molecular processing unit need to be amplified in order to be useful. We have developed a nanomicrointerface to read information encoded in molecular level potentials and to amplify this signal to microelectronic levels. The amplification is performed by making the output molecular potential slightly twist the torsional angle between two rings of a pyridazine, 3,6-bis(phenylethynyl) (aza-OPE) molecule, requiring only fractions of kcal/mol energies. In addition, even if the signal from the molecular potentials is not enough to turn the ring or even if the angles are the same for different combinations of outputs, still the current output yields results that resemble the device as a field effect transistor, providing the possibility to reduce channel lengths to the range of just 1 or 2 nm. The slight change in the torsional angle yields readable changes in the current through the aza-OPE biased by an external applied voltage. Using ab initio methods, we computationally demonstrate the amplification of molecular potential signals into currents that can be read by standard circuits.

Molecular electrostatic potential devices on graphite and silicon surfaces.

We demonstrate that molecular gates using molecular electrostatic potentials (MEP) can be used on hydrogen-passivated silicon substrates without any disturbance of their behavior in vacuum; however, the use of graphite as a substrate strongly affects such behavior. As expected, the substrate may become one more design variable. The ability to have several substrate alternatives is very important for the practical implementation of this new scenario based on molecular potentials. In general, the effect of the substrate can be predetermined by calculating the MEP of the surface as this indicates how strongly its intrinsic potential is.

Influence of the chronic administration of LH-RH agonist on the oral glucose tolerance test in patients with prostatic carcinoma

La terapia crónica con agonistas de LH-RH, ha demostrado ser una buena alternativa a la castración quirúrgica o la terapia estrogénica en hombres con cáncer de próstata metastásico. La administración crónica produce un bloqueo persistente del eje hipófisis-gónadas en pacientes con carcinoma prostático, ésto condiciona un estado de supresión gonadal denominado "castración farmacológica". Otros tumores hormonodependientes (mama, pâncreas), así como también la miomatosis uterina, la endometriosis y la pubertad precoz, han sido tratados con análogos agonistas de LH-RH. Después de la primera semana de tratamiento con el análogo, se ha observado un incremento importante en el apetito y en el peso corporal. Se seleccionaron 15 pacientes con adenocarcinoma de próstata en estadio D-2, para tratamiento con D-TRP-6-LH-RH. Se realizó una curva de tolerancia a la glucosa (CTG) pretratamiento, y a los 3, 6 y 12 meses durante la terapia. Previo a la terapia, 8 pacientes tuvieron CTG normal y 7 de tipo diabético manteniendose este tipo de respuesta prácticamente sin cambios, durante la terapia con D-TRP-6-LH-RH. En ambos grupos, la administración inicial de D-TRP-6-LH-RH, libró LH y FSH. Al mes y durante la terapéutica, los valores de LH y FSH se mantuvieron en niveles subnormales. Los niveles iniciales séricos de testosterona, estuvieron dentro de límites normales, cayendo a niveles de castración durante el tratamiento