Anti-endotoxin antibodies consumption in cardiovascular collapse: Pathophysiological concerns / Consumo de anticuerpos antiendotoxina en el shock: relación etiológica

Objective Abnormal endotoxin activity in critically ill patients has been described in the absence of Gram-negative bacterial (GNB) infection. As disease severity seems to be crucial in the detection of this phenomenon, we decided to assess and compare endotoxin exposure in those patients representing the critical situation: septic shock and cardiogenic shock. Design Prospective, observational non intervention study. Setting Critical Care Department of a University tertiary hospital. Patients Cardiogenic shock (CS) and septic shock (SS) patients. Interventions None. Measurements and main results Follow-up was performed for the first three days. Inflammatory biomarkers (C-reactive protein, procalcitonin and interleuquin-6) and IgM antiendotoxin-core antibodies titter (IgM EndoCAb) were daily analyzed. Sixty-two patients were included; twenty-five patients with SS and thirty-seven with CS. Microbial etiology was established in 23 SS patients (92%) and GNB were present in 13 cases (52%). Although infection was suspected and even treated in 30 CS patients (81%), any episode could be finally confirmed. EndoCAb consumption was more intense in SS patients, although twenty-two CS patients (59.5%) had IgM anti-endotoxin value below 10th percentile range for healthy people. No statistically significant difference in endotoxin exposure was detected between Gram-positive and Gram-negative infections in the SS group. Endotoxin exposure ability to distinguish between SS and CS was moderate (AUC 0.7892, 95% IC: 0.6564–0.9218).Conclusions In the severely ill patient some mechanisms take place allowing endotoxin incursion and therefore blurring the limits of diseases pathophysiology. Our work representatively shows how exposure to endotoxin was not fully capable of distinguishing between CS and SS. (AU)

Objetivo En el paciente crítico se ha descrito una actividad incrementada de la endotoxina no asociada a infección por bacterias gramnegativas (BGN). La gravedad de la enfermedad influye en este fenómeno, por ello realizamos este estudio en el paciente crítico por antonomasia: shock séptico y cardiogénico. Diseño Estudio prospectivo, observacional, sin intervención.Lugar de estudioUnidad de Cuidados Intensivos. Pacientes Pacientes en shock cardiogénico (SC) o séptico (SS).Intervención Ninguna. Determinaciones y principales resultados Seguimiento durante los 3 primeros días. Proteína C reactiva, procalcitonina e interleucina-6, y el título de anticuerpos IgM anti-edotoxina (IgM EndoCAb) se analizaron diariamente. Se incluyó a 62 pacientes; 25 con SS y 37 con SC. La etiología fue identificada en 23 pacientes con SS (92%), los BGN estuvieron presentes en 13 casos (52%). Se sospechó e incluso trató la infección en 30 pacientes con SC, pero en ningún caso se pudo confirmar. El consumo de EndoCAb fue más intenso en los pacientes con SS, pero 22 pacientes con SC (59,5%) tuvieron unos valores por debajo del percentil 10. Los niveles de EndoCAb no fueron significativamente diferentes entre las infecciones por BGN y cocos grampositivos. La capacidad de EndoCab para diferenciar entre SC y SS resultó ser moderada (AUC 0,7892; IC del 95%, 0,6564-0,9218).Conclusiones En el paciente crítico es frecuente que la endotoxina provoque una respuesta inflamatoria y la sumación de distintos mecanismos fisiopatológicos. En este sentido, nuestro trabajo pone de manifiesto que la determinación de exposición a endotoxina no es totalmente capaz de distinguir entre los pacientes con SC y SS. (AU)

Anti-endotoxin antibodies consumption in cardiovascular collapse: Pathophysiological concerns.

OBJECTIVE: Abnormal endotoxin activity in critically ill patients has been described in the absence of Gram-negative bacterial (GNB) infection. As disease severity seems to be crucial in the detection of this phenomenon, we decided to assess and compare endotoxin exposure in those patients representing the critical situation: septic shock and cardiogenic shock. DESIGN: Prospective, observational non intervention study. SETTING: Critical Care Department of a University tertiary hospital. PATIENTS: Cardiogenic shock (CS) and septic shock (SS) patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Follow-up was performed for the first three days. Inflammatory biomarkers (C-reactive protein, procalcitonin and interleuquin-6) and IgM antiendotoxin-core antibodies titter (IgM EndoCAb) were daily analyzed. Sixty-two patients were included; twenty-five patients with SS and thirty-seven with CS. Microbial etiology was established in 23 SS patients (92%) and GNB were present in 13 cases (52%). Although infection was suspected and even treated in 30 CS patients (81%), any episode could be finally confirmed. EndoCAb consumption was more intense in SS patients, although twenty-two CS patients (59.5%) had IgM anti-endotoxin value below 10th percentile range for healthy people. No statistically significant difference in endotoxin exposure was detected between Gram-positive and Gram-negative infections in the SS group. Endotoxin exposure ability to distinguish between SS and CS was moderate (AUC 0.7892, 95% IC: 0.6564-0.9218). CONCLUSIONS: In the severely ill patient some mechanisms take place allowing endotoxin incursion and therefore blurring the limits of diseases pathophysiology. Our work representatively shows how exposure to endotoxin was not fully capable of distinguishing between CS and SS.

Competency assessment of residents of Intensive Care Medicine through a simulation-based objective structured clinical evaluation (OSCE). A multicenter observational study.

OBJECTIVES: The current official model of training in Intensive Care Medicine (ICM) in Spain is based on exposure to experiences through clinical rotations. The main objective was to determine the level of competency (I novice to V independent practitioner) achieved by the residents at the end of the 3rd year of training (R3) in ICM through a simulation-based OSCE. Secondary objectives were: (1) To identify gaps in performance, and (2) To investigate the reliability and feasibility of conducting simulation-based assessment at multiple sites. DESIGN: Observational multicenter study. SETTING: Thirteen Spanish ICU Departments. PARTICIPANTS: Thirty six R3. INTERVENTION: The participants performed on five, 15-min, high-fidelity crisis scenarios in four simulation centers. The performances were video recorded for later scoring by trained raters. MAIN VARIABLES OF INTEREST: Via a Delphi technique, an independent panel of expert intensivists identified critical essential performance elements (CEPE) for each scenario to define the levels of competency. RESULTS: A total of 176 performances were analyzed. The internal consistency of the check-lists were adequate (KR-20 range 0.64-0.79). Inter-rater reliability was strong [median Intraclass Correlation Coefficient across scenarios: 0.89 (0.65-0.97)]. Competency levels achieved by R3 were: Level I (18.8%), II (35.2%), III (42.6%), IV/V (3.4%). Overall, a great heterogeneity in performance was observed. CONCLUSION: The expected level of competency after one year in the ICU was achieved only in half of the performances. A more evidence-based educational approach is needed. Multiple center simulation-based assessment showed feasibility and reliability as an evaluation method of competency. TRIAL REGISTRATION: COBALIDATION. NCT04278976. (https://register. CLINICALTRIALS: gov).

Competency assessment of residents of Intensive Care Medicine through a simulation-based objective structured clinical evaluation (OSCE). A multicenter observational study / Evaluación del nivel de competencia de residentes de Medicina Intensiva mediante una evaluación clínica, objetiva y estructurada basada en simulación (ECOE). Estudio multicéntrico observacional

Objectives The current official model of training in Intensive Care Medicine (ICM) in Spain is based on exposure to experiences through clinical rotations. The main objective was to determine the level of competency (I novice to V independent practitioner) achieved by the residents at the end of the 3rd year of training (R3) in ICM through a simulation-based OSCE. Secondary objectives were: (1) To identify gaps in performance, and (2) To investigate the reliability and feasibility of conducting simulation-based assessment at multiple sites. Design Observational multicenter study. Setting Thirteen Spanish ICU Departments. Participants Thirty six R3. Intervention The participants performed on five, 15-min, high-fidelity crisis scenarios in four simulation centers. The performances were video recorded for later scoring by trained raters. Main variables of interes Via a Delphi technique, an independent panel of expert intensivists identified critical essential performance elements (CEPE) for each scenario to define the levels of competency. Results A total of 176 performances were analyzed. The internal consistency of the check-lists were adequate (KR-20 range 0.64–0.79). Inter-rater reliability was strong [median Intraclass Correlation Coefficient across scenarios: 0.89 (0.65–0.97)]. Competency levels achieved by R3 were: Level I (18.8%), II (35.2%), III (42.6%), IV/V (3.4%). Overall, a great heterogeneity in performance was observed. Conclusio The expected level of competency after one year in the ICU was achieved only in half of the performances. A more evidence-based educational approach is needed. Multiple center simulation-based assessment showed feasibility and reliability as an evaluation method of competency (AU)

Objetivos El modelo de formación en medicina intensiva (MI) en España se basa en la experiencia adquirida durante una serie de rotaciones programadas por diferentes áreas clínicas. El objetivo principal del estudio fue determinar el nivel de competencia (I principiante – V autónomo) de los residentes de MI al finalizar el tercer año de residencia (R3) mediante una ECOE basada en simulación. Objetivos secundarios: 1) identificar brechas en el desempeño; 2) investigar la fiabilidad y validez de una ECOE simulada multicéntrica como método de evaluación. Diseño Estudio multicéntrico observacional. Ámbito Trece servicios españoles de Medicina Intensiva. Participantes Treinta y seis R3. Intervención Los 36 R3 participaron en cinco escenarios clínicos simulados de 15 minutos de duración en cuatro centros de simulación. Las actuaciones se grabaron en video y posteriormente se calificaron por pares de expertos. Variables de interés principales Un panel de intensivistas expertos seleccionó mediante el método Delphi los elementos críticos esenciales de cada escenario para definir los niveles de competencia. Resultados La consistencia interna de los listados de verificación fue adecuada (KR-20:0,64-0,79). La fiabilidad interjueces fue elevada (coeficiente de correlación intraclase [mediana]: 0,89 [0,65-0,97]). Los niveles de competencia conseguidos fueron: nivel I (18,8%), II (35,2%), III (42,6%), IV/V (3,4%). Globalmente, se observó una gran heterogeneidad en el desempeño. Conclusión El nivel de competencia esperado se logró únicamente en la mitad de las actuaciones. Se necesita un modelo de formación más basado en objetivos y evidencias. La evaluación mediante escenarios simulados en múltiples centros demostró ser factible y fiable (AU)

Evaluación del impacto del parto mediante cesárea frente el parto vaginal en mujeres con depresión posparto: revisión sistemática cualitativa / Evaluation of the impact of caesarean delivery versus vaginal delivery in women with postpartum depression: a review

La depresión posparto es una patología frecuente, estigmatizada, con implicaciones socio-familiares. El objetivo es revisar si existe relación entre el parto mediante cesárea comparado con la vía vaginal de parto, en el riesgo de padecer depresión posparto. En la revisión se realiza una búsqueda en PubMed; se incluyeron estudios donde se comparaba el parto vaginal vs. cesárea en relación con la depresión posparto. Tras aplicar los criterios de elegibilidad, se obtuvieron 11 artículos de interés. La literatura revisada mostró resultados heterogéneos y no concluyentes respecto a la relación directa entre la vía de parto y la depresión posparto. La asociación de la vía de parto con el riesgo de padecer este trastorno sigue siendo controversial.(AU)

Postpartum depression is a very frequent, yet stigmatized illness, and it may carry serious family and social implications. The main aim of this review is to review whether there is a link between caesarean section and the risk of postpartum depression, compared with vaginal delivery. The main search was performed on PubMed. Articles that compared vaginal delivery with caesarean section in relation to postpartum depression were included. After applying eligibility criteria, 11 relevant articles were obtained. The reviewed literature showed heterogeneous and inconclusive results regarding the direct link between delivery mode and postpartum depression. Conclusions. The relationship between mode of delivery and risk of postpartum depression remains controversial.(AU)

Análisis de la aceptación y validez de los métodos utilizados para la implementación de un programa de formación basado en competencias en un servicio de Medicina Intensiva de un hospital universitario de referencia / Acceptance and validity of the methods used to implement a competency based medical education programme in an Intensive Care Department of a teaching referral center

Objetivos: 1) Determinar la satisfacción de tutores y residentes con la metodología utilizada para la implementación de CoBaTrICE, y 2) determinar la validez y la fiabilidad de las escalas de valoración global diseñados ad hoc para analizar el desempeño de los residentes con fines formativos. Diseño: Estudio prospectivo de cohortes. Participantes: Todos los residentes y tutores del Servicio de Medicina Intensiva del Hospital Universitario y Politécnico La Fe de Valencia. Intervención: En marzo del 2016 se inició la implementación de CoBaTrICE sustentada en: 1) formación de los tutores en técnicas de retroalimentación; 2) realización por los residentes de múltiples ejercicios reales de evaluación objetiva y estructurada para adquirir las competencias del programa, y 3) uso de un portafolio electrónico para registrar las evidencias del progreso y estimular la reflexión. Métodos: La satisfacción con CoBaTrICE se evaluó mediante una encuesta realizada tras 9 meses de implementación a los 15 residentes y 5 tutores del servicio. Se preguntó sobre la metodología de las evaluaciones, calidad de la retroalimentación, autorregulación del aprendizaje y utilidad del portafolio. Se determinaron la consistencia interna (alfa de Cronbach), índices de generalizabilidad y fiabilidad interjueces (índice de correlación intraclase) de las escalas de valoración global. Resultados: La aplicación de CoBaTrICE fue satisfactoria en todas las dimensiones estudiadas. Se constataron la validez y la fiabilidad de las escalas de valoración utilizadas. Conclusiones: La metodología utilizada para implementar CoBaTrICE fue valorada positivamente por tutores y residentes. Las escalas de valoración global utilizadas en la evaluación formativa demostraron ser válidas, fiables y reproducibles. (AU)

Objectives; 1. To determine the satisfaction of tutors and residents with a specific methodology used to implement CoBaTrICE; 2. To determine the reliability and validity of the global rating scales designed ad hoc to assess the performance of the residents for training purposes. Design Prospective cohort study Participants All the residents and tutors of the ICU Department of the Hospital Universitario y Politécnico la Fe de Valencia. Intervention CoBaTrICE implementation started in March 2016, it was based on: 1) Training the tutors in feedback techniques; 2) Performing multiple objective and structured work based assessments to achieve the competences of the program; and 3) The use of an electronic portfolio to promote learning reflection and to collect the evidence that learning was taking place. Methods The acceptance of CoBaTrICE was explored through a satisfaction survey conducted after 9 months of implementation of the training program. The 15 residents and 5 tutors of the ICU Department were asked about the methodology of the formative assessments, the quality of the feedback, self-learning regulation and the electronic portfolio usefulness. The validity of the global rating scales was assessed through the tests alfa de Cronbach, reliability and generalizability indexes, and intraclass correlation coefficient. Results The implementation of CoBaTrICE was satisfactory in all the dimensions studied. The global rating scales used for formative purposes showed reliability and validity. Conclusions The methodology used to implement CoBaTrICE was highly valued by tutors and residents. The global rating scales used for formative purposes showed reliability and validity. (AU)

Acceptance and validity of the methods used to implement a competency based medical education programme in an Intensive Care Department of a teaching referral center.

OBJECTIVES: 1. To determine the satisfaction of tutors and residents with a specific methodology used to implement CoBaTrICE. 2. To determine the reliability and validity of the global rating scales designed ad hoc to assess the performance of the residents for training purposes. DESIGN: Prospective cohort study. PARTICIPANTS: All the residents and tutors of the ICU Department of the Hospital Universitario y Politécnico la Fe de Valencia. INTERVENTION: CoBaTrICE implementation started in March 2016, it was based on: (1) Training the tutors in feedback techniques; (2) Performing multiple objective and structured work based assessments to achieve the competences of the program; and (3) The use of an electronic portfolio to promote learning reflection and to collect the evidence that learning was taking place. METHODS: The acceptance of CoBaTrICE was explored through a satisfaction survey conducted after 9 months of implementation of the training program. The 15 residents and 5 tutors of the ICU Department were asked about the methodology of the formative assessments, the quality of the feedback, self-learning regulation and the electronic portfolio usefulness. The validity of the global rating scales was assessed through the tests alfa de Cronbach, reliability and generalizability indexes, and intraclass correlation coefficient. RESULTS: The implementation of CoBaTrICE was satisfactory in all the dimensions studied. The global rating scales used for formative purposes showed reliability and validity. CONCLUSIONS: The methodology used to implement CoBaTrICE was highly valued by tutors and residents. The global rating scales used for formative purposes showed reliability and validity.

Leucemia mieloide aguda secundaria al tratamiento de los tumores ginecológicos: a propósito de dos casos / Acute myeloid leukaemia associated with the treatment of gynaecological tumours: Report of two clinical cases

Las neoplasias hematológicas secundarias representan una complicación grave del tratamiento oncológico, aunque se desconoce su incidencia real en las pacientes con tumores ginecológicos. El diagnóstico de la leucemia mieloide aguda secundaria a platinos se basa en la sospecha clínica, las alteraciones morfológicas y el estudio citogenético. A pesar de la quimioterapia paliativa y el trasplante alogénico, que está limitado a ciertos casos, su pronóstico es desfavorable. Por ello deben optimizarse las pautas terapéuticas en los tumores ginecológicos con posibilidad de obtener largas supervivencias y mantener a los pacientes en programas de seguimiento prolongado

Secondary haematological malignancies represent severe complication of cancer treatment, although their real incidence is unknown in gynaecological tumours. The usual presentation of an acute leukaemia associated with platinum is based on clinical and cytogenetic features. Diagnosis is based on clinical suspicion, morphological alterations and cytogenetic studies. Conventional chemotherapy is mainly palliative, whereas allogenic transplantation allows the cure but just a small percentage of cases, so prognosis is dismal. Thus, potential curative therapies for solid tumours should be optimized and patients maintained in long-term surveillance programs

Haemodialysis significantly reduces serum levetiracetam levels inducing epileptic seizures: Case report.

WHAT IS KNOWN AND OBJECTIVE: Levetiracetam is used in the treatment of some forms of epilepsy. In renal impairment and patients on chronic haemodialysis, dose adjustment is required. We report a case. CASE DESCRIPTION: This case report describes a woman on levetiracetam treatment who presented with generalized tonic-clonic seizures during a haemodialysis session. We report on treatment adjustment and on the impact of dialysis on levetiracetam levels. WHAT IS NEW AND CONCLUSION: Haemodialysis reduces serum levetiracetam concentration and can lead to subtherapeutic levels. Close monitoring is necessary when dialysis is used on patients receiving anticonvulsant drugs that are extensively eliminated by the procedure.

A prognostic index for locoregional recurrence after neoadjuvant chemotherapy.

BACKGROUND: The appropriate selection criteria for breast-conserving surgery (BCS) or mastectomy after neoadjuvant chemotherapy (NAC) are poorly defined. The aim of this study is to analyse the incidence and prognostic factors for locoregional recurrence (LRR) in patients with breast cancer (BC) treated with NAC to develop a prognostic score to help with clinical decision-making. MATERIALS AND METHODS: Using our retrospective maintained BC database, we identified 730 patients treated with NAC (327 patients treated with BCS and 403 patients treated with mastectomy) between 1998 and 2014. To identify variables associated with an increased LRR rate, we performed firstly Kaplan-Meier curves, with comparisons among groups using log-rank test, and then, significant variables were included in a multivariate analysis using Cox proportional hazards. The prognostic index was developed by assigning score 0 (favourable) or score 1 (unfavourable) for each significant variable of multivariate analysis and was created separately for patients with BCS and mastectomy. RESULTS: At a median follow-up of 72 months, the 6-year cumulative incidence of LRR was 7.2% ( ± 3%) for BCS and 7.9% ( ± 3%) for mastectomy. By univariate analysis, variables associated with an increased LRR were for BCS: HER2 positive, grade III, ductal carcinoma in situ (DCIS), No-pCR (ypTis, ypN0), and age < 40 years; and for mastectomy, HER2-positive, DCIS, No-pCR, and LVI. By multivariate analysis, variables associated with an increased LRR were for BCS: HER2 positive (HR: 11.1, p = 0.001), DCIS (HR: 3.1, p = 0.005), and age < 40 years (HR: 2.8, p = 0.02); and for mastectomy: HER2 positive (HR: 9.5, p = 0.03), DCIS (HR: 2.7, p = 0.01), No-pCR (HR: 11.4, p = 0.01), and age < 40 years (HR: 2.8, p = 0.006). The score stratified patients into three subsets with statistically different levels of risk for LRR. For BCS, the six-year LRR rates were 3%, 13%, and 33% for the low (score 0, n = 120), intermediate (score 1, n = 95) and high (score 2-3, n = 27) risk groups, respectively (p = 0.001). For mastectomy, the six-year LRR rates were 0%, 8%, and 27% for the low (score 0, n = 20), intermediate (score 1-2, n 191), and high (score 3-4, n = 30) risk groups, respectively (p = 0.001). Of note, 21 patients that had a LRR event were HER2 positive, all of them had received trastuzumab. CONCLUSIONS: Patients with a score of 0, which made up to 19% of the study population, had very low risk of LRR. The score enabled the identification of a small group (7%) of patients with very high risk of LRR, and who may benefit from alternative treatment.

Platinum polyoxoniobates.

Reaction of [Nb6O19](8-) with [Pt(OH)4(H2O)2] upon heating yielded first characterized platinum polyniobates. A dimeric complex [Nb6O19{Pt(OH)2}]2(12-) (1) is produced in a 1 : 1 molar ratio. Increasing the Pt/Nb6 molar ratio to 1 : 2 yields a mixture of 1 and a sandwich-type complex [Pt(Nb6O19)2](12-) (2).

Grafting {Cp*Rh}(2+) on the surface of Nb and Ta Lindqvist-type POM.

New hybrid POM based on Lindqvist-type polyoxometalates [M6O19](8-) (M = Nb, Ta) and organometallic fragment {Cp*Rh}(2+) have been isolated and characterized. X-ray quality crystals of K4[(Cp*Rh)2Nb6O19]·20H2O () and Cs4[(Cp*Rh)2Ta6O19]·18H2O () were obtained from solutions with {Cp*Rh} : [M6O19](8-) stoichiometry 2 : 1. The solution behavior of the hybrid polyoxoanions was studied with ESI-MS and (1)H DOSY NMR. Amongst the poorly investigated chemistry of polyoxotantalates, complex is the first complex bearing a grafted organometallic fragment. The formation of 1 : 1 complexes was detected by ESI-MS techniques.

Coordination-induced condensation of [Ta6O19](8-): synthesis and structure of [{(C6H6)Ru}2Ta6O19](4-) and [{(C6H6)RuTa6O18}2(µ-O)](10-).

Reaction of [(C6H6)RuCl2]2 and Na8[Ta6O19] gives two new hybrid organometallic POM complexes, Na10[{(C6H6)RuTa6O18}2(µ-O)]·39.4H2O (Na10-1) and Na4(trans-[{(C6H6)Ru}2Ta6O19]·20H2O (Na4-2). In both cases the half-sandwich fragments {(C6H6)Ru}(2+) are coordinated as additional vertices to the {Ta3(µ2-O)3} triangles of the hexatantalate. According to NMR and ESI-MS data, the dimeric complex [{(C6H6)RuTa6O18}2(µ-O)](10-) dissociates in water with the formation of monomeric [(C6H6)RuTa6O19](6-) species (1a). X-ray structural characterization and aqueous speciation of the complexes by (13)C, (1)H, and DOSY NMR; ESI-MS; and capillary electrophoresis (CE) have been carried out.

New {RuNO} polyoxometalate [PW11O39Ru(II)(NO)]4-: synthesis and reactivity.

New Ru-containing polyoxometalate [PW11O39Ru(II)(NO)](4-) (1(4-)) was obtained in high yield by reaction of [Ru(NO)Cl5](2-) with [PW11O39](7-) and characterized by multinuclear NMR, cyclic voltammetry, IR spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). The intrinsic reactivity of the {RuNO} site in 1(4-) toward various reagents has been studied using a versatile and simple ESI tandem mass spectrometric methodology for identification of the L attached at the Ru site; this approach relies on the preferential liberation of the L ligands attached at the Ru sites upon mass-selecting desired intermediates and subsequent promotion of their fragmentation. Reactions with both hydrazine and hydroxylamine lead to elimination of the nitroso group and quantitative formation of [PW11O39Ru(III)(H2O)](4-) (2(4-)) in aqueous solution. In the reaction with hydroxylamine, an intermediate with coordinated dinitrogen has been detected. An easy access to the NH3-coordinated [PW11O39RuNH3](4-) (3(4-)) complex was achieved upon reduction of 1(4-) with Sn(2+) in water.

Trapping {BW12}2 tungstoborate: synthesis and crystal structure of hybrid [{(H2BW12O42)2O}{Mo6O6S6(OH)4(H2O)2}]14- anion.

Reaction between monolacunary {BW(11)} tungstoborate and oxothiocationic building block, {Mo(2)O(2)S(2)}, results in the formation of a new polyoxothiometalate with a unique architecture in which two [H(2)BW(12)O(43)](9-) tungstoborate subunits are linked together with a hexamolybdate [Mo(V)(6)O(6)S(6)(OH)(4)(H(2)O)(2)](2+) bridge.

Monosomía parcial 10p de novo / De novo partial monosomy 10p

No disponible

Preparation and properties of the full series of cuboidal clusters [Mo(x)W4-xSe4(H2O)12]n+ (n = 4-6) and their derivatives.

Hydrothermal reactions between incomplete cuboidal cluster aqua complexes [M3Q4(H2O)9]4+ and M(CO)6 (M = Mo, W; Q = S, Se) offer easy access to the corresponding cuboidal clusters M4Q4. The complete series of homometal and mixed Mo/W clusters [Mo(x)W4-xQ4(H2O)12]n+ (x = 0-4, n = 4-6) has been prepared. Upon oxidation of the mixed-metal clusters, it is the W atom which is lost, allowing selective preparation of new trinuclear clusters [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+. The aqua complexes were converted by ligand exchange reactions into dithiophosphato and thiocyanato complexes, and crystal structures of [W4S4((EtO)2PS2)6], [MoW3S4((EtO)2PS2)6], [Mo4Se4((EtO)2PS2)6], [W4Se4((i-PrO)2PS2)6], and (NH4)6[W4Se4(NCS)12]-4H20 were determined. Cyclic voltammetry was performed on [Mo(x)W4-xCO4(H2O)12]n+, showing reversible redox waves 6+/5+ and 5+/4+. The lower oxidation states are more difficult to access as the number of W atoms increases. The [Mo2WSe4(H2O)9]4+ and [MoW2Se4(H2O)9]4+ species were derivatized into [Mo2WSe4(acac)3(py)3]+ and [MoW2Se4(acac)3(py)3]+, which were also studied by CV. When appropriate, the products were also characterized by FAB-MS and NMR (31P, 1H) data.

Vibrational coupling as diagnostic for intramolecular hydrogen bonds of carbohydrates in aqueous solution.

The coupling of nuC-O and deltaO-D vibrations in the 1200-900 cm(-1) IR range leads to band shifting in opposite directions, which provides information on intramolecular hydrogen bonding of carbohydrates in aqueous solution. The aqueous solution IR spectra of 2-acetamide-1,6-anhydro-2-deoxy-D-glucopyranose and cis-1,2-cyclopentanediol and tetrahydrofuran-ethanol mixtures are reported. Frequency upshifting upon deuteration is observed for the nuC-O bands of both a hydrogen bond acceptor and donor in ether-hydroxyl and hydroxyl-hydroxyl contacts. The 1200-900 cm(-1) range can be used to reveal the presence of intramolecular hydrogen bonds in aqueous carbohydrates, unlike the OH stretching region, which cannot be used in this sense due to carbohydrate band masking by the strong nuOH IR absorption of water.