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Computational modeling at the DLPNO-CCSD(T)/CBS//M06-L/def2-TZVP level of theory was used to propose four different iron catalysts whose structures were inspired on the [Fe]-hydrogenase active site: [Fe(MePNNHNP)(acmp)] (C(1), MePNNHNP = 2,6-bis(dimethylphosphine), acmp = acylmethylpyridine), [Fe(CNNHNC)(acmp)] (C(2), CNNHNC = 2,6-bis(methylimidazol-2-ylidene)), [Fe(MePNNNP)(acmp)] (D(1), MePNNNP = 2,6-bis((dimethylphosphine)pyridine)), and [Fe(CNNNC)(acmp)] (D(2), CNNNC = 2,6-bis((methylimidazol-2-ylidene) pyridine)). Through these electronic structure calculations, the catalytic mechanism of the reaction was explored. The intermediates and transition states present along the reaction coordinate were identified and described as to their equilibrium geometries, vibrational frequencies, and energies. Quasi-harmonic corrections were performed considering conditions analogous to those used experimentally. To compare the catalytic activities of the studied catalysts, turnover frequencies (TOFs) were calculated. Based on the explored catalytic cycles and TOF values (D(1) > C(1) > D(2) > C(2)), the most suitable iron catalysts are those with tridentate phosphine pincer-type ligands coordinated to the metal center. These systems are new promising iron catalysts to promote the CO2 hydrogenation to formic acid without any use of bases or additives.

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We report a computational study of the mechanism and determination of the rate constants of the Fe + CO2→ FeO + CO reaction, in the 1000-3000 K temperature range, at the CCSD(T)/CBS//B3LYP/def2-TZVP level of theory. The overall rate constant was obtained by a Kinetic Monte Carlo simulation. The calculated rate constant, at 2000 K, is 9.72 × 10-13 cm3 molecule-1 s-1, in agreement with experimental measurements: 2.97 × 10-13 cm3 molecule-1 s-1 [A. Giesen et al., Phys. Chem. Chem. Phys., 2002, 4, 3665] and 1.13 × 10-13 cm3 molecule-1 s-1 [V. N. Smirnov, Kinet. Catal., 2008, 49, 607]. Our study shows that this reaction follows a complex mechanism, with multiple reaction paths contributing to the overall rate, and that CCSD(T) accurately describes this transition metal reaction.

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Abstract Objective: To evaluate the clinical features associated with adrenocortical hormone overexpression and familial cancer profiling as potential markers for early detection of adrenocortical tumors in children from South and Southeast Brazil. Methods: The clinical manifestations and anthropometric measurements of 103 children diagnosed with adrenocortical tumors were analyzed. Results: Between 1982 and 2011, 69 girls and 34 boys diagnosed with adrenocortical tumors were followed-up for a median time of 9.0 years (0-34 years). Signs of androgen overproduction alone (n = 75) or associated with cortisol (n = 18) were present in 90.3%. TP53 p.R337H mutation was found in 90.5% of patients. Stages I, II, III, and IV were observed in 45.6%, 27.2%, 19.4%, and 7.8% of patients, respectively. At diagnosis, there were no significant differences in height (p = 0.92) and weight (p = 0.22) among children with adrenocortical tumors, but children with virilization alone had significantly higher height-for-age Z-scores (0.92 ± 1.4) than children with hypercortisolism alone or combined (−0.32 ± 1,8; p = 0.03). The five-year overall survival was 76.7% (SD ± 4.2). Patients with advanced-stage disease had a significantly worse prognosis than those with limited disease (p < 0.001). During follow-up, ten of 55 p.R337H carrier parents developed cancer, whereas none of the 55 non-carriers did. Conclusions: Signs of adrenocortical hormone overproduction appear early, even in cases with early-stage. These signs can be identified at the physical examination and anthropometric measurements. In southern Brazil, pediatric adrenocortical tumor is a sentinel cancer for detecting families with germline p.R337H mutation in TP53 gene.

Resumo Objetivo: Avaliar as manifestações clínicas da hiperexpressão de hormônios do córtex da adrenal e câncer familiar como marcadores para a detecção precoce de tumores adrenocorticais em crianças do Sul e Sudeste do Brasil. Pacientes e métodos: Foram analisadas as manifestações clínicas e antropométricas de 103 crianças diagnosticadas com tumores adrenocorticais. Resultados: Entre 1982 e 2011, 69 meninas e 34 meninos diagnosticados com tumores adrenocorticais foram acompanhados por um tempo mediano de nove anos (0-34). Ao diagnóstico, sinais de virilização isolada (n = 75) ou associada ao cortisol (n = 18) estavam presentes em 90,3% dos pacientes; a mutação do gene TP53 p.R337H foi identificada em 90,5% dos pacientes. Os pacientes foram classificados em estádio I (45,6%), II (27,2%), III (19,4%) e IV (7,8%). Ao diagnóstico, não houve diferença significativa para as medidas de altura (p = 0,92) e de peso (p = 0,22) entre as crianças com tumores adrenocorticais, mas crianças com virilização tiveram escore-Z mais elevado para a idade (0,92 ± 1,4) do que aquelas com hipercortisolismo isolado ou combinado (−0,32 ± 1,8; p = 0,03). A sobrevida global de cinco anos foi de 76,7% (DP ± 4,2). Pacientes com estádios avançados tiveram pior prognóstico (p < 0,001). Durante o seguimento, 10 dos 55 genitores portadores da p.R337H desenvolveram câncer, enquanto que nenhum caso ocorreu entre os 55 não portadores. Conclusões: Os sinais de hiperprodução de hormônios adrenocorticais aparecem precocemente no desenvolvimento do tumor e podem ser identificados pelo exame físico e pelas medidas antropométricas na consulta pediátrica de rotina. O tumor adrenocortical pediátrico é sentinela para a detecção de câncer em famílias que segregam a mutação germinativa p.R337H do gene TP53.

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OBJECTIVE: To evaluate the clinical features associated with adrenocortical hormone overexpression and familial cancer profiling as potential markers for early detection of adrenocortical tumors in children from South and Southeast Brazil. METHODS: The clinical manifestations and anthropometric measurements of 103 children diagnosed with adrenocortical tumors were analyzed. RESULTS: Between 1982 and 2011, 69 girls and 34 boys diagnosed with adrenocortical tumors were followed-up for a median time of 9.0 years (0-34 years). Signs of androgen overproduction alone (n=75) or associated with cortisol (n=18) were present in 90.3%. TP53 p.R337H mutation was found in 90.5% of patients. Stages I, II, III, and IV were observed in 45.6%, 27.2%, 19.4%, and 7.8% of patients, respectively. At diagnosis, there were no significant differences in height (p=0.92) and weight (p=0.22) among children with adrenocortical tumors, but children with virilization alone had significantly higher height-for-age Z-scores (0.92±1.4) than children with hypercortisolism alone or combined (-0.32±1,8; p=0.03). The five-year overall survival was 76.7% (SD±4.2). Patients with advanced-stage disease had a significantly worse prognosis than those with limited disease (p<0.001). During follow-up, ten of 55 p.R337H carrier parents developed cancer, whereas none of the 55 non-carriers did. CONCLUSIONS: Signs of adrenocortical hormone overproduction appear early, even in cases with early-stage. These signs can be identified at the physical examination and anthropometric measurements. In southern Brazil, pediatric adrenocortical tumor is a sentinel cancer for detecting families with germline p.R337H mutation in TP53 gene.

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A complete state-averaged active space self-consistent field (SA-CASSCF) calculation by means of the SA-CASSCF(18,14)-in-BP86 Miller-Manby embedding approach was performed to explore the ground and excited electronic states of the trans-[RuCl(NO)(NH3)4]2+ complex. Insights into the NO photodissociation mechanism and Ru-NO bonding properties are provided. In addition, spin-orbit (SO) interactions were taken into account to describe and characterize the spin-forbidden transitions observed at the low-energy regions of the trans-[RuCl(NO)(NH3)4]2+ UV-Vis spectrum. The SA-CASSCF(18,14)-in-BP86 electronic spectrum is in great agreement with the experimental data of Schreiner [Schreiner et al., Inorg. Chem., 1972, 11, 880].

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In this article, triazolylidene-derived N-heterocyclic olefins (trNHOs) are designed using computational quantum tools, and their potential to promote CO2 sequestration is tested and discussed in detail. The low barrier heights related to the trNHO-mediated process indicate that the tailored compounds are very promising for fast CO2 sequestration. The systematic analysis of the presence of distinct substitutes at different N positions of the trNHO ring allows us to rationalize their effect on the carboxylation process and reveal the best N-substituted trNHO systems for CO2 sequestration and improved trNHO carboxylates for faster CO2 capture/release.

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We report reaction cross sections, energy disposal, and rate constants for the OH + HBr → Br + H2O and OH + DBr → Br + HDO reactions from quasiclassical trajectory calculations using an ab initio potential energy surface [ de Oliveira-Filho , A. G. S. ; Ornellas , F. R. ; Bowman , J. M. J. Phys. Chem. Lett. 2014 , 5 , 706 - 712 ]. Comparison with available experiments are made and generally show good agreement.

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We report a permutationally invariant, ab initio potential energy surface (PES) for the OH + HBr → Br + H2O reaction. The PES is a fit to roughly 26 000 spin-free UCCSD(T)/cc-pVDZ-F12a energies and has no classical barrier to reaction. It is used in quasiclassical trajectory calculations with a focus on the thermal rate constant, k(T), over the temperature range 5 to 500 K. Comparisons with available experimental data over the temperature range 23 to 416 K are made using three approaches to treat the OH rotational and associated electronic partition function. All display an inverse temperature dependence of k(T) below roughly 160 K and a nearly constant temperature dependence above 160 K, in agreement with experiment. The calculated rate constant with no treatment of spin-orbit coupling is overall in the best agreement with experiment, being (probably fortuitously) within 20% of it.

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The O((3)P) + HBr → OH + Br and O((3)P) + DBr → OD + Br reactions are studied on a recent high-quality ab initio-based potential energy surface. Thermal rate constants over the 200-1000 K temperature range, calculated using variational transition-state theory (VTST) with the small-curvature tunneling (SCT) correction and quantum mechanical methods with the J-shifting approximation (QM/JS) for zero total angular momentum (J = 0), are reported. These results are compared to the available experimental data, which lie in the ranges of 221-554 and 295-419 K for O + HBr and O + DBr, respectively. The rate constants, in cm(3) molecule(-1) s(-1) and at 298 K, for the O + HBr reaction are 3.66 × 10(-14) for VTST, 3.80 × 10(-14) for QM/JS, and 3.66 × 10(-14) for the average of eight experimental measurements.

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A high-level ab initio investigation of a manifold of electronic states of the diatomic dication TeH(2+) is presented. Potential energy curves for both Λ + S and relativistic (Ω) states are constructed not only making evident the metastability of this system, but also the large energy splitting due to spin-orbit interactions. This effect is also very significant in the region close to the crossing of the (2)Π and (4)Σ(-) states, where avoided crossings between the Ω states have a relatively large impact on the height of the energy barriers. In contrast to TeH, with only two bound states (X1 (2)Π3∕2 and X2 (2)Π1∕2) below about 25,000 cm(-1), in the case of TeH(2+) a much richer energy profile is obtained indicating various possibilities of electronic transitions. Guided by the results of this study, the experimental characterization of these states is now a challenge to spectroscopists. Since close to the equilibrium region the double positive charge is centered on the tellurium atom, the binding in this system can be rationalized as a simple covalent bond between the pz and s orbitals of Te(2+) and H, respectively. As the internuclear distance increases, the electron affinity of Te(2+) overcomes that of H(+) and the system dissociates into two singly charged fragments. A simulation of the double ionization spectra complements the characterization of the electronic states, and results of a mass spectrometric investigation corroborates the predicted transient existence of this metastable species.

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OBJECTIVE: To report a fuzzy logic mathematical model to predict postoperative vomiting (POV) in pediatric oncologic patients and compare with preexisting scores. BACKGROUND: Although POV has a high incidence in children and may decrease parental satisfaction after surgeries, there is only one specific score that predicts POV in children: the Eberhart's score. In this study, we report a fuzzy model that intends to predict the probability of POV in pediatric oncologic patients. Fuzzy logic is a mathematical theory that recognizes more than simple true and false values and takes into account levels of continuous variables such as age or duration of the surgery. The fuzzy model tries to account for subjectiveness in the variables. METHODS: Preoperative potential risk factors for POV in 198 children (0-19 year old) with malignancies were collected and analyzed. Data analysis was performed with the chi-square test and logistic regression to evaluate probable risk factors for POV. A system based on fuzzy logic was developed with the risk factors found in the logistic regression, and a computational interface was created to calculate the probability of POV. RESULTS: The model showed a good performance in predicting POV. After the analysis, the model was compared with Eberhart's score in the same population and showed a better performance. CONCLUSIONS: The fuzzy score can predict the chance of POV in children with cancer with good accuracy, allowing better planning for postoperative prophylaxis of vomiting. The computational interface is available for free download at the internet and is very easy to use.

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In this work, we report the construction of potential energy surfaces for the (3)A('') and (3)A(') states of the system O((3)P) + HBr. These surfaces are based on extensive ab initio calculations employing the MRCI+Q/CBS+SO level of theory. The complete basis set energies were estimated from extrapolation of MRCI+Q/aug-cc-VnZ(-PP) (n = Q, 5) results and corrections due to spin-orbit effects obtained at the CASSCF/aug-cc-pVTZ(-PP) level of theory. These energies, calculated over a region of the configuration space relevant to the study of the reaction O((3)P) + HBr → OH + Br, were used to generate functions based on the many-body expansion. The three-body potentials were interpolated using the reproducing kernel Hilbert space method. The resulting surface for the (3)A('') electronic state contains van der Waals minima on the entrance and exit channels and a transition state 6.55 kcal/mol higher than the reactants. This barrier height was then scaled to reproduce the value of 5.01 kcal/mol, which was estimated from coupled cluster benchmark calculations performed to include high-order and core-valence correlation, as well as scalar relativistic effects. The (3)A(') surface was also scaled, based on the fact that in the collinear saddle point geometry these two electronic states are degenerate. The vibrationally adiabatic barrier heights are 3.44 kcal/mol for the (3)A('') and 4.16 kcal/mol for the (3)A(') state.

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We report a unique case of synchronous functional adrenocortical adenoma and an incidental myelolipoma within ectopic cortical adrenal tissue located in the renal hilum in a child with Beckwith-Wiedemann syndrome and review the association between adrenal gland disorders and myelolipomas. To the best of our knowledge, this is the first documented case of a simultaneous occurrence of these three conditions. A 17-month-old child with Beckwith-Wiedemann syndrome was diagnosed with a left adrenal tumor during complementary radiologic studies. Biochemical investigation before surgery showed elevated blood levels of cortisol and dehydroepiandrosterone hormones. The patient underwent a left adrenalectomy with ipsilateral renal hilar and intercaval-aortic lymph node dissection. Pathology findings revealed a left adrenocortical adenoma and an incidental myelolipoma growing within ectopic cortical adrenal tissue in the renal hilum. The patient is doing well and does not have any current health issues. Patients with adrenal cortex disorders, such as hyperplasias and neoplasms, particularly when associated with hormonal imbalances, may have an increased risk of developing myelolipomas. Whether Beckwith-Wiedemann syndrome may, by itself, contribute to simultaneous occurrence of adrenocortical adenomas and myelolipomas remains to be clarified.

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Extensive ab initio calculations using a complete active space second-order perturbation theory wavefunction, including scalar and spin-orbit relativistic effects with a quadruple-zeta quality basis set were used to construct an analytical potential energy surface (PES) of the ground state of the [H, O, I] system. A total of 5344 points were fit to a three-dimensional function of the internuclear distances, with a global root-mean-square error of 1.26 kcal mol(-1). The resulting PES describes accurately the main features of this system: the HOI and HIO isomers, the transition state between them, and all dissociation asymptotes. After a small adjustment, using a scaling factor on the internal coordinates of HOI, the frequencies calculated in this work agree with the experimental data available within 10 cm(-1).

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UNLABELLED: OBJECTIVES AND INTRODUCTION: Gastroschisis is a congenital abdominal wall defect with increasing occurrence worldwide over the past 20-30 years. Our aim was to analyze the morbidity of newborns after gastroschisis closure, with emphasis on metabolic and hydroelectrolyte disturbances in patients at three tertiary university centers. METHODS: From January 2003 to June 2009, the following patient data were collected retrospectively: (A) Background maternal and neonatal data: maternal age, prenatal diagnosis, type of delivery, Apgar scores, birth weight, gestational age and sex; (B) Surgical modalities: primary or staged closure; and (C) Hospital course: levels of serum sodium and levels of serum albumin in the two first postoperative days, number of ventilation days, other postoperative variables and survival. Statistical analyses were used to examine the associations between some variables. RESULTS: 163 newborns were included in the study. Primary closure of the abdominal defect was performed in 111 cases (68.1%). The mean serum sodium level was 127.4 ± 6.7 mEq/L, and the mean serum albumin level was 2.35 ± 0.5 g/dL. Among the correlations between variables, it was verified that hyponatremia and hypoalbuminemia correlated with the number of days on the ventilator but not with the number of days on total parenteral nutrition (TPN); mortality rate correlated with infection. The final survival rate was 85.9%. CONCLUSION: In newborns with gastroschisis, more aggressive attention to hyponatremia and hypoalbuminemia would improve the outcome.

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OBJECTIVES AND INTRODUCTION: Gastroschisis is a congenital abdominal wall defect with increasing occurrence worldwide over the past 20-30 years. Our aim was to analyze the morbidity of newborns after gastroschisis closure, with emphasis on metabolic and hydroelectrolyte disturbances in patients at three tertiary university centers. METHODS: From January 2003 to June 2009, the following patient data were collected retrospectively: (A) Background maternal and neonatal data: maternal age, prenatal diagnosis, type of delivery, Apgar scores, birth weight, gestational age and sex; (B) Surgical modalities: primary or staged closure; and (C) Hospital course: levels of serum sodium and levels of serum albumin in the two first postoperative days, number of ventilation days, other postoperative variables and survival. Statistical analyses were used to examine the associations between some variables. RESULTS: 163 newborns were included in the study. Primary closure of the abdominal defect was performed in 111 cases (68.1 percent). The mean serum sodium level was 127.4¡6.7 mEq/L, and the mean serum albumin level was 2.35¡0.5 g/dL. Among the correlations between variables, it was verified that hyponatremia and hypoalbuminemia correlated with the number of days on the ventilator but not with the number of days on total parenteral nutrition (TPN); mortality rate correlated with infection. The final survival rate was 85.9 percent. CONCLUSION: In newborns with gastroschisis, more aggressive attention to hyponatremia and hypoalbuminemia would improve the outcome.

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OBJECTIVE: Report the results of laparoscopic upper-pole nephroureterectomy in infants. MATERIALS AND METHODS: Six consecutive infants underwent 7 laparoscopic upper-pole nephroureterectomy. Pre and postoperative evaluation included renal sonography, voiding cystourethrogram and renal scintigraphy. All infants showed upper-pole exclusion. Surgery was performed through a transperitoneal approach with full flank position in all infants. Three or 4 ports were used according to the necessity of retracting the liver. The distal ureter was ligated close to the bladder whenever reflux was present and the dysplastic upper-pole was divided with the help of an electrocautery. Data regarding operative time, postoperative use of analgesics, time to resume oral feeding, hospital stay and tubular function were collected and analyzed. RESULTS: All procedures were concluded as planned. Mean operative time was 135 min. One patient underwent staged bilateral upper-pole nephrectomy. There were no complications and the postoperative hospital stay was 48 hours in 5 procedures and 24 hours in 2 procedures. Pain medication was required only in the first day. Renal tubular function showed improvement in half of the cases. CONCLUSION: Laparoscopic partial nephrectomy is a safe and feasible procedure in infants. Due to the magnification provided by the lenses, a better vision of the structures is achieved, facilitating selective dissection of vascular upper-pole, renal parenchyma and distal ureter. This approach is less damaging to the lower pole, and is associated to low morbidity and a short hospital stay.

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OBJECTIVE: Report the results of laparoscopic upper-pole nephroureterectomy in infants. MATERIALS AND METHODS: Six consecutive infants underwent 7 laparoscopic upper-pole nephroureterectomy. Pre and postoperative evaluation included renal sonography, voiding cystourethrogram and renal scintigraphy. All infants showed upper-pole exclusion. Surgery was performed through a transperitoneal approach with full flank position in all infants. Three or 4 ports were used according to the necessity of retracting the liver. The distal ureter was ligated close to the bladder whenever reflux was present and the dysplastic upper-pole was divided with the help of an electrocautery. Data regarding operative time, postoperative use of analgesics, time to resume oral feeding, hospital stay and tubular function were collected and analyzed. RESULTS: All procedures were concluded as planned. Mean operative time was 135 min. One patient underwent staged bilateral upper-pole nephrectomy. There were no complications and the postoperative hospital stay was 48 hours in 5 procedures and 24 hours in 2 procedures. Pain medication was required only in the first day. Renal tubular function showed improvement in half of the cases. CONCLUSION: Laparoscopic partial nephrectomy is a safe and feasible procedure in infants. Due to the magnification provided by the lenses, a better vision of the structures is achieved, facilitating selective dissection of vascular upper-pole, renal parenchyma and distal ureter. This approach is less damaging to the lower pole, and is associated to low morbidity and a short hospital stay.

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OBJETIVO: Avaliar os resultados anatômicos e cosméticos das genitoplastias feminizantes realizadas em meninas com genitália ambígua devido à Hiperplasia Congênita das Adrenais (HCA). CASUíSTICA E MÉTODOS: Vinte e sete meninas com HCA e ambigüidade genital (Prader III-V) foram submetidas a genitoplastia feminizante em um estágio e acompanhadas por período médio de quatro anos. Em doze meninas, dois retalhos labioescrotais em ilha foram associados à genitoplastia convencional para adequar os grandes lábios e ampliar o intróito vaginal. Episódios de infecção urinária foram observados em dezesseis meninas no pré-operatório e em apenas sete no pós-operatório. Os resultados cosméticos foram avaliados por meio de sistematização da avaliação anatômica das diferentes estruturas RESULTADOS: Os da clitoroplastia foram considerados bons em 62,9 por cento dos casos; houve atrofia clitoriana em quatro meninas. Excesso de grandes lábios ocorreu em 25 por cento, e persistência do seio-urogenital em 11 por cento (três meninas nas quais não havia sido associado retalho labioescrotal). O retalho labioescrotal em ilha foi considerado de simples confecção e reprodução. Cinco meninas precisaram ser re-operadas. De um modo geral, os resultados cosméticos foram considerados ótimos ou bons em 63 por cento dos casos, satisfatórios em 18,5 por cento e insatisfatórios ou ruins em 18,5 por cento. CONCLUSÕES: Os resultados anatômicos e cosméticos foram classificados como bons na maioria dos casos, porém alguns aspectos técnicos devem ser ajustados com a intenção de evitar complicações irreversíveis e re-operações.

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OBJECTIVE: To evaluate the anatomical and cosmetic results of feminizing genitoplasty in girls with ambiguous genitalia due to Congenital Adrenal Hyperplasia (CAH). CASUISTIC AND METHOD: Twenty-seven females with genital ambiguity (Prader III-V) due to CAH underwent an one-stage feminizing genitoplasty and were followed for a mean time of 4 years. In twelve girls, two cutaneous labioscrotal island-flaps were associated with the conventional genitoplasty, to decrease the excess of labia majora and to enlarge the vaginal introitus. Urinary tract infections were observed in sixteen girls in the preoperative and in only seven in the postoperative period. The cosmetic results were obtained by the systematic anatomical evaluation of the different structures that compose the genitalia. RESULTS: The results of clitoroplasty were considered good in 63% of the cases; however, 4 girls developed clitoral atrophy. An excess of labia majora was present in 25% and persistence of the urogenital sinus occurred in 11% (three children without labioscrotal island flap). The labioscrotal island flap was considered technically feasible and reproducible. Five girls had to be re-operated. The cosmetic results were considered excellent or good in 63% of the cases, satisfactory in 18.5% and unsatisfactory or bad in 18.5%. CONCLUSIONS: The anatomical and cosmetic results were good in majority of the cases; however, some technical aspects should be adjusted, to avoid irreversible sequels and re-operations.

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