Structures and internal dynamics of diphenylether and its aggregates with water.

We report on a detailed multi-spectroscopic analysis of the structures and internal dynamics of diphenylether and its aggregates with up to three water molecules by employing molecular beam experiments. The application of stimulated Raman/UV and IR/UV double resonance methods as well as chirped-pulse Fourier transform microwave spectroscopy in combination with quantum-chemical computations yield the energetically preferred monomer and cluster geometries. Furthermore, the complex internal dynamics of the diphenylether monomer and the one-water clusters are analysed. In the cluster with three water molecules, water forms a cyclic structure similar to the isolated water trimer. The interactions ruling the structures of the higher-order water clusters are a combination of the ones identified for the two monohydrate isomers, with dispersion being a decisive contribution for systems that have a delicate energetic balance between different hydrogen-bonded arrangements of similar energy.

Systematic endoscopic assessment of bleeding sites in severe epistaxis: the role of the S-point and the superior epistaxis.

BACKGROUND: Systematic endoscopic assessment (SEA) of bleeding sites is critical for topodiagnosis and treatment of severe epistaxis, which is not limited to the posterior region. A bleeding site originating from the ethmoidal vasculature, the S-point, has recently been described. The aim of this study is to ascertain the prevalence of each bleeding site in severe epistaxis using a SEA protocol that includes the S-point. METHODOLOGY: Prospective longitudinal study of 51 severe epistaxis patients who underwent 53 SEA under general anesthesia from April 2018 through March 2019. SEA consisted of use of a rigid nasal endoscope; no reduction in blood pressure; no use of topical vasoconstrictor; systematic search of all regions of the nose. Bleeding sites were assigned to either superior or posterior epistaxis. RESULTS: At least one bleeding site was identified in 37 evaluations (69.8%). The S-point was the most common bleeding site (28.3%), followed by the lateral middle turbinate (9.4%), non-S-point upper septum (7.5%), nasal roof (7.5%), and upper lateral wall (7.5%). Superior epistaxis was identified in the most of cases (27 SEA, 50.9%), whereas only 14 SEA (26.4%) identified posterior epistaxis â€" fewer than the 16 SEA that did not identify any bleeding sites (30.2%). There were two recurrences (3.8%). CONCLUSIONS: Systematic endoscopic assessment effectively identified bleeding sites in 69.8% of severe epistaxis. The S-point was the most common bleeding site identified (28.3%). Finally, superior epistaxis corresponded to more than half of the identified bleeding sites, demonstrating the importance of examining this region judiciously in patients with severe epistaxis.

Actuación del odontólogo legista en catástrofes: enseñanzas del protocolo de Interpol / Forensic dentist´s role in catastrophes: teaching of the Interpol protocol

Una catástrofe es un acontecimiento súbito y violento que genera múltiples víctimas requiriendo del abordaje de expertos en diferentes áreas del conocimiento técnico científico para lograr una identificación inequívoca. El rol del odontólogo legista como integrante de los equipos interdisciplinarios conformados para la investigación en este tipo de hechos aparece definido en el Protocolo de Interpol, guía de operaciones estandarizada, diseñada para optimizar la comunicación, planificación, organización y estrategias entre peritos de diferentes latitudes ante incidentes naturales, accidentales o intencionales. El presente trabajo tiene por objetivo analizar las directrices de la citada norma en lo atinente a la coordinación de la actuación de los equipos de odontólogos legistas para contribuir en tales contextos, apuntada fundamentalmente a auxiliar a la justicia, aportando mayor celeridad en la identificación humana y acotando la angustia e incertidumbre de los familiares de la víctimas (AU)

Diferencias por género a través del estudio de los tipos de huellas labiales en estudiantes de posgrado de la Facultad de Odontología de la Universidad de Buenos Aires / Gender differences through the study of lip prints types in postdoctoral students from the School of Dentistry, University of Buenos Aires

Las huellas labiales representan una alternativa para la identificación humana por ser únicas en cada persona. Se buscó establecer la frecuencia de tipos de huellas labiales en estudiantes de Posgrado de la Facultad de Odontología de la Universidad de Buenos Aires, tomando como referencia la clasificación de Suzuki y Tsuchihashi. Se realizó un estudio descriptivo en 50 hombres y 50 mujeres. Se fotografiaron los labios de cada participante, aplicando posteriormente lápiz labial a los efectos de que efectúen impresiones sobre un soporte de papel, estableciéndose los diferentes tipos de huellas. Se transcribieron los datos a una ficha diseñada a tal afecto y las fotografías se almacenaron en una computadora, conformando una base de datos. Para el género femenino, el tipo labial II (líneas bifurcadas), se halló en el 100% de la muestra. En el género masculino los tipos labiales predominantes fueron el I (líneas verticales completas) y II (líneas bifurcadas), ambos presentes en 48 participantes (96%). No existe diferencia significativa entre la frecuencia de tipos de huellas labiales en ambos géneros, por lo que sería factible la identificación humana en Argentina, desde el punto de vista poblacional e individual, en personas con similares características que la muestra estudiada (AU)

Estandarización de prótesis dentales mediante codificación personal incluida en bases termoácido resistentes con fines de identificación forense / Dental prosthesis standarization by means of thermal-acid resistant-included personal code, for forensic identification purposes

La identificación categórica de un cadáver no sólo es importante por razones humanitarias y emocionales, sino también por sus efectos legales y administrativos. Durante el proceso de identificación humana, toda la información necesaria se obtiene del cuerpo desconocido de la víctima, permitiendo cumplir el objetivo de que su perfil sea reconstruido. Se utilizan sistemas de marcado y etiquetado de prótesis dentales en diferentes situaciones, detallándose métodos directos e indirectos para tal fin. Se propone la incorporación del número del documento nacional de identidad (DNI) en todas las prótesis removibles y fijas, con el fin de adoptar un único y definitivo código de identificación personal con el objetivo de lograr un método uniforme, estandarizado, sencillo y rápido para la identificación forense en pacientes atendidos en la Facultad de Odontología de la Universidad de Buenos Aires.

The categorical identification of a corpse is not only important for humanitarian and emotional reasons, but also for legal andadministrative purposes. During the human identification process, all necessary information is gathered from the unknown body of thevictim and hence that an objective reconstructed profile can be established. Denture marking and labeling systems are being used in varioussituations, and a number of direct and indirect methods are reported. Is proposed that national identity number (DNI) be incorporated inall removable and fixed prostheses, so as to adopt a single and definitive personal identification code with the aim of achieving a uniform,standardized, easy, and fast identification method in patients treated at the Faculty of Dentistry at the University of Buenos Aires forforensic identification.

Structural analyses of isolated cyclic tetrapeptides with varying amino acid residues.

Cyclic peptides represent a large class of substances that occur in nature with important biological and medical functions. Synthetic cyclic peptides are used as artificial receptors due to a series of advantages over conventional receptors. In order to optimize their binding abilities, investigations of their intrinsic structural properties especially with regard to the influence of different amino acid residues are fundamental. Here we report the structural analysis of two synthetic cyclic tetrapeptides cyclo[l-Tyr(Me)-d-Pro-l-Ala-d-Pro] (CPAla) and cyclo[l-Tyr(Me)-d-Pro-l-Glu(Me)-d-Pro] (CPGlu) in a molecular beam by means of combined IR/UV spectroscopic techniques. Structural assignments were achieved by comparing experimentally obtained vibrations and harmonically calculated frequencies including dispersion corrections (B3LYP-D3/TZVP). The investigated cyclic peptides contain an arrangement of an amino acid sequence which is no longer symmetric compared to the former investigations of the cyclo[l-Tyr(Me)-d-Pro]2 peptide. It turns out that all investigated compounds prefer conformations stabilized by two internal hydrogen bonds. In the case of CPGlu containing a flexible side chain with a terminal hydrogen bond acceptor an additional structure was observed in which a hydrogen bond between the terminal carboxylate group and a ring NH group is formed.

Roles y responsabilidades del odontólogo como auxiliar de la justicia / Dentists´ roles and responsibilities as auxiliaries to justice

La ciencia odontológica cuenta con diversas metodologías a la hora de brindar auxilio a la Justicia, tanto en la resolución de casos criminales como en procedimientos de índole civil y laboral. La odontología legal requiere de un trabajo interdisciplinario con las otrasespecialidades odontológicas. En ese contexto, el rol capital del perito odontólogo es contribuir al esclarecimiento de la identidad de unapersona. El diente es susceptible de variantes fisiológicas y patológicas en sus estructuras, como así también estigmas inherentes a los tratamientos restauradores, hechos que confiere información dental que individualiza a una persona. Las piezas dentarias pueden ser utilizadas como un arma en determinadas circunstancias, brindando información relevante sobre los caracteres odontológicos de la víctimay/o del agresor, pudiendo entonces desempeñar la odontología legal un importante rol en la investigación de situaciones de agresión sexual yabuso en todas las edades. El odontólogo en su tarea asistencial tiene la responsabilidad de labrar y documentar de manera fiel y completasu devenir profesional, pudiendo ser requerido por las autoridades encargadas de administrar Justicia en casos de responsabilidad profesional, negligencia, fraude, abuso, e identificación de restos humanos.

Dental science has various methodologies when providing aid to justice, both in solving criminal cases and civil procedures and labor issues.Legal Dentistry requires interdisciplinary work with other dental specialties. In this context, the principal role of the dentist expert is helpclarify the identity of a person. The tooth is subject to physiological and pathological variations in their structures, as well as inherentstigmas restorative treatments, facts which confers dental individualized information to a person. The teeth can be used as a weapon incertain circumstances, providing relevant information about dental characteristics of the victim and/or perpetrator can then LegalDentistry play an important role in investigating cases of sexual assault and abuse in all the ages. The dentist in their care task isresponsible for faithfully document and complete their professional procedure that may be required by the authorities responsible foradministering justice in cases of professional liability, negligence, fraud, abuse, and identification of human remains.

Structural investigations on a linear isolated depsipeptide: the importance of dispersion interactions.

In this paper we present the first investigations on an isolated linear depsipetide CyCO-Gly-Lac-NH-PhOMe (cyclohexylcarbonyl-glycine-lactate-2-anisidine abbreviated as MOC) in a molecular beam experiment. Depsipeptides are a special subclass of peptides which contain at least one ester bond replacing a peptide bond. This leads to a different folding behavior and a different biological activity compared to a "normal" peptide. In order to analyze the folding of an isolated depsipeptide on a molecular level a variety of combined IR/UV methods including IR/IR/UV experiments are applied to MOC. Three different isomers are identified in combination with DFT calculations using the hybrid functional B3LYP-D3 with a TZVP basis set. The most stable structure shows a tweezer-like arrangement between the aromatic chromophore and the aliphatic cyclohexyl ring. A characteristic feature of this structure is that it is stabilized by dispersion interactions resulting from CH/π interactions. If dispersion is not taken into account this structural arrangement is no longer a minimum on the potential energy surface indicating the importance of dispersion interactions.

Investigation of the hydrated 7-hydroxy-4-methylcoumarin dimer by combined IR/UV spectroscopy.

The first molecular beam investigations on a coumarin dimer and clusters of a coumarin dimer with water both in the neutral (S0) and cationic (D0) electronic ground state are performed. The structure and structural changes due to ionization of the isolated 7-hydroxy-4-methylcoumarin dimer (7H4MC)2 as well as its mono- and dihydrate (7H4MC)2(H2O)1-2 are analyzed by applying combined IR/UV spectroscopy compared with density functional theory calculations. In case of the neutral dimer of 7H4MC a doubly hydrogen-bonded structure is formed. This doubly hydrogen-bonded arrangement opens to a singly hydrogen-bonded structure in the ion presenting a rearrangement reaction within an isolated dimer. By attaching one or two water molecules to the neutral 7H4MC dimer water is inserted into the hydrogen bonds. In contrast to the non-hydrated species this general binding motif with water in a bridging function does not change via ionization but especially for the dihydrate the spatial arrangement of the two 7H4MC units changes strengthening the interaction between the aromatic chromophores. The presented analyses illustrate the strong dependence of binding motifs as a function of successive hydration and charge including a rearrangement reaction.

A combined IR/IR and IR/UV spectroscopy study on the proton transfer coordinate of isolated 3-hydroxychromone in the electronic ground and excited state.

In this paper the excited state proton transfer (ESPT) of isolated 3-hydroxychromone (3-HC), the prototype of the flavonols, is investigated for the first time by combined IR/UV spectroscopy in molecular beam experiments. The IR/UV investigations are performed both for the electronically excited and electronic ground state indicating a spectral overlap of transitions of the 3-HC monomer and clusters with water in the electronic ground state, whereas in the excited state only the IR frequencies of the proton-transferred monomer structure are observed. Due to the loss of isomer and species selectivity with respect to the UV excitations IR/IR techniques are applied in order to figure out the assignment of the vibrational transitions in the S0 state. In this context the quadruple resonance IR/UV/IR/UV technique (originally developed to distinguish different isomers in the electronically excited state) could be applied to identify the OH stretching vibration of the monomer in the electronic ground state. In agreement with calculations the OH stretching frequency differs significantly from the corresponding values of substituted hydroxychromones.

Mechanical disfunction in the mucosal oedema formation of patients with nasal polyps.

BACKGROUND: Nasal polyposis (NP) is characterized by an anomalous tissue growth with oedema and a lack of extracellular matrix. In this study, we investigated whether a mechanical disfunction of the forces that act in oedema formation is present in NP. METHODS: We compared the interstitial hydrostatic pressure behaviour during a saline solution infusion between healthy nasal mucosa (inferior and middle turbinate from 10 patients) and inflamed nasal mucosa from NP patients (inferior, middle turbinate and a nasal polyp from 6 patients). We used Controlled Disc Stimulation equipment to compare the curve Pressure/Volume created during the saline solution infusion. RESULTS: The pressure at 0.2 ml infusion was lower in the middle turbinate of NP patients than in the middle turbinate of control patients. The lowest P/V mean assessed was in the polypoid tissue. CONCLUSIONS: The interstitial hydrostatic pressure showed different behaviour during liquid infusion in nasal mucosa from NP patients when compared with healthy nasal mucosa. This study allows us to cogitate on a new pathophysiological mechanism contributing to the development of the NP.

Effect of adenotonsillectomy on visual attention tests among children with sleep-disordered breathing: a controlled prospective cohort study.

OBJECTIVE: This study aimed to evaluate the effect of adenotonsillectomy on visual attention and daytime sleepiness in children with sleep-disordered breathing. DESIGN: This was a controlled prospective cohort study. SETTING: Outpatients from the Otorhinolaryngology Division of Edmundo Vasconcelos Hospital Complex, São Paulo, Brazil. PARTICIPANTS: Patients aged 6-17 years with upper airway obstruction scheduled to undergo adenotonsillectomy (treatment group) in the Otorhinolaryngology Division of Edmundo Vasconcelos Hospital Complex, in São Paulo, Brazil. Participants of control group were consecutively selected from another outpatient clinic of paediatric surgery, but those with symptoms of sleep-disordered breathing were excluded. MAIN OUTCOME MEASURES: Children were submitted to visual attention tests (TAVIS-3) that discriminates normal subjects from those with attentional disorders in advance of the surgery and 2 months later, and in the same period for the control group. Parents were interviewed about lifestyle, sleep characteristics and daytime sleepiness. RESULTS: The analysis included 27 patients in the adenotonsillectomy group and 30 controls, who had similar age (10.0 ± 3.3 versus 10.3 ± 3.7 years; P = 0.8), gender (41% boys versus 57%, respectively) and body mass index. There was marked decrease in daytime sleepiness after surgery (delta between groups: -4.7 ± 3.8; P < 0.001), as well as reductions in reaction time, errors of omission and errors of commission in the treatment compared with the control group at both time points, before and after surgery. CONCLUSIONS: This study shows that adenotonsillectomy in children and adolescents with sleep-disordered breathing reduces daytime sleepiness and improves the performance in tests of visual attention.

Enhancement of ferroelectric polarization stability by interface engineering.

By using theoretical predictions based on first-principle calculations, we explore an interface engineering approach to stabilize polarization states in ferroelectric heterostructures with a thickness of just several nanometers.

Emergence of USA300 MRSA in a tertiary medical centre: implications for epidemiological studies.

Community-associated meticillin-resistant Staphylococcus aureus (CA-MRSA) has become a major pathogen, particularly in outbreaks of skin and soft-tissue infection (SSTI). A preliminary study conducted at our institution in 2004 revealed that up to 45% of inpatient and 70% of outpatient MRSA isolates tested were the USA300 genotype. In this report, we used pulsed-field gel electrophoresis (PFGE) in a retrospective analysis to determine the time when CA-MRSA USA300 moved from the community to the inpatient population. During the five-year period 2000 to 2004, unique MRSA isolates (N=253) were selected from inpatients in surgical and medical intensive care units, the general hospital population and outpatients. The most common PFGE types found in all populations from 2000 to 2003 were USA100, USA200 and USA600. USA300 was absent from all inpatients from 2000 to 2003 and only sporadic numbers found in the outpatient group. However, in 2004 the USA300 strain emerged in both outpatient and hospitalised patients. There was no difference in the distribution of USA300 between ICUs and the general inpatient population. The emergence of CA-MRSA has resulted in a shift of the MRSA strains that are implicated in healthcare-associated infections in our institution. This has been a recent development that has implications as to the use of PFGE to determine transmission of MRSA in the inpatient setting. Further evaluation of these data in the context of the epidemiology of these infections is needed to determine if more discriminatory approaches to typing will be required for monitoring the spread of the more virulent CA-MRSA phenotype within the inpatient population.

Association between antecedent intravenous antimicrobial exposure and isolation of vancomycin-resistant enterococci.

Vancomycin-resistant enterococci (VRE) have become important causes of nosocomial infections. This study evaluated the association between a variety of intravenous antimicrobial exposures and the isolation of VRE using two control groups: (1) a vancomycin-susceptible enterococci (VSE) group, to assess factors associated with development of VRE, and (2) a nonenterococci control group, to assess factors associated with positive cultures for enterococci without regard to vancomycin resistance. After adjusting for the effect of other antimicrobials, time at risk, and patient morbidity, compared to vancomycin-susceptible enterococci controls, exposures to imipenem (OR = 4.9, 95% CI = 1.6-14.1) and ceftazidime (OR = 2.6, 95% CI = 1.1-6.1) were significant predictors of VRE. When compared to nonenterococci controls, exposures to ampicillin (OR = 20.1, 95% CI = 1.5-263.1) and imipenem (OR = 5.1, 95% CI = 1.5-17.1) were significantly associated with VRE. Neither piperacillin nor vancomycin was associated with VRE compared to either control group. This study offers further evidence that the replacement of broad-spectrum cephalosporins by extended-spectrum penicillins, specifically piperacillin, may be effective in reducing VRE.

Prednisolona e Clarirtromicina no tratamento da rinossinusite aguda - estudo multicêntrico brasileiro / Predisolone and Clarythromicin in the treatment of acute rhinosinusitis - brazilian multicenter study

A rinossinusite bacteriana aguda é uma afecção de alta prevalência, na sua maioria originada de viroses das vias aéreas superiores. A terapia antimicrobiana com a claritromicina está bem estabelecida na literatura e corticoterapia sistêmica contribui como adjuvante no controle da inflamação, diminuindo o edema, facilitando a drenagem das secreções e a manutenção da permeabilidade dos óstios, favorecendo assim a cura clínica.

Vancomycin-resistant enterococci: 15 years and counting.

We review the history of vancomycin-resistant enterococci (VRE) and propose a causal model illustrating the roles of exposure to VRE reservoirs, patient characteristics, antimicrobial exposure, and prevalence of VRE in the progression from potential VRE reservoirs to active disease in hospitalized patients. Differences in VRE colonization and VRE infection are discussed with respect to hospital surveillance methodology and implications for interventions. We further document clonal transmission of VRE in a large, urban, teaching hospital and demonstrate VRE susceptibility to a wide array of antimicrobial agents. This model can guide the identification of mutable factors that are focal points for intervention.