Revealing the Nature of Active Oxygen Species and Reaction Mechanism of Ethylene Epoxidation by Supported Ag/α-Al2O3 Catalysts.

The oxygen species on Ag catalysts and reaction mechanisms for ethylene epoxidation and ethylene combustion continue to be debated in the literature despite decades of investigation. Fundamental details of ethylene oxidation by supported Ag/α-Al2O3 catalysts were revealed with the application of high-angle annular dark-field-scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy (HAADF-STEM-EDS), in situ techniques (Raman, UV-vis, X-ray diffraction (XRD), HS-LEIS), chemical probes (C2H4-TPSR and C2H4 + O2-TPSR), and steady-state ethylene oxidation and SSITKA (16O2 → 18O2 switch) studies. The Ag nanoparticles are found to carry a considerable amount of oxygen after the reaction. Density functional theory (DFT) calculations indicate the oxidative reconstructed p(4 × 4)-O-Ag(111) surface is stable relative to metallic Ag(111) under the relevant reaction environment. Multiple configurations of reactive oxygen species are present, and their relevant concentrations depend on treatment conditions. Selective ethylene oxidation to EO proceeds with surface Ag4-O2* species (dioxygen species occupying an oxygen site on a p(4 × 4)-O-Ag(111) surface) only present after strong oxidation of Ag. These experimental findings are strongly supported by the associated DFT calculations. Ethylene epoxidation proceeds via a Langmuir-Hinshelwood mechanism, and ethylene combustion proceeds via combined Langmuir-Hinshelwood (predominant) and Mars-van Krevelen (minor) mechanisms.

Design of Cr-Free Promoted Copper-Iron Oxide-Based High-Temperature Water-Gas Shift Catalysts.

The effect of Ce addition to the Cr-free Al-promoted Cu-Fe oxide-based catalysts is investigated. Catalyst characterization (X-ray diffraction (XRD), in situ Raman spectroscopy, high-sensitivity low-energy ion scattering (HS-LEIS), Brunauer-Emmett-Teller (BET) analysis), CO-temperature-programmed reduction chemical probing, and steady-state WGS activity reveal that (i) in the absence of Al, Ce addition via coprecipitation has a detrimental effect on the catalytic activity related to the poor thermostability and formation of less active Ce-Cu-O NPs, (ii) the addition of Ce via coprecipitation also does not improve the performance of the CuAlFe catalyst because of the formation of a thick CeOx overlayer on the active Cu-FeOx interface, and (iii) impregnation of Ce onto the CuAlFe catalyst exhibits significant improvement in catalytic performance due to the formation of a highly active CeOx-FeOx-Cu interfacial area. In summary, Al does not surface-segregate and serves as a structural promoter, while Ce and Cu surface-segregate and act as functional promoters in Ce/CuAlFe mixed oxide catalysts.

Influence of 2'-Modifications (O-Methylation, Fluorination, and Stereochemical Inversion) on the Base Pairing Energies of Protonated Cytidine Nucleoside Analogue Base Pairs: Implications for the Stabilities of i-Motif Structures.

Naturally occurring and chemically engineered modifications are among the most powerful strategies explored for fine-tuning the conformational characteristics and intrinsic stability of nucleic acids topologies. Modifications at the 2'-position of the ribose or 2'-deoxyribose moieties differentiate nucleic acid structures and have a significant impact on their electronic properties and base-pairing interactions. 2'-O-Methylation, a common post-transcriptional modification of tRNA, is directly involved in modulating specific anticodon-codon base-pairing interactions. 2'-Fluorinated and arabino nucleosides possess novel and beneficial medicinal properties and find use as therapeutics for treating viral diseases and cancer. However, the potential to deploy 2'-modified cytidine chemistries for tuning i-motif stability is largely unknown. To address this knowledge gap, the effects of 2'-modifications including O-methylation, fluorination, and stereochemical inversion on the base-pairing interactions of protonated cytidine nucleoside analogue base pairs, the core stabilizing interactions of i-motif structures, are examined using complementary threshold collision-induced dissociation techniques and computational methods. The 2'-modified cytidine nucleoside analogues investigated here include 2'-O-methylcytidine, 2'-fluoro-2'-deoxycytidine, arabinofuranosylcytosine, 2'-fluoro-arabinofuranosylcytosine, and 2',2'-difluoro-2'-deoxycytidine. All five 2'-modifications examined here are found to enhance the base-pairing interactions relative to the canonical DNA and RNA cytidine nucleosides with the greatest enhancements arising from 2'-O-methylation and 2',2'-difluorination, suggesting that these modifications should well be tolerated in the narrow grooves of i-motif conformations.

Congenital Zika syndrome / Síndrome congénito por virus Zika

Abstract In February 2016, the World Health Organization declared Zika virus (ZIKV) infection a public health emergency of international concern because it caused congenital Zika syndrome (CZS). The CZS is considered a specific pattern of birth defects caused by ZIKV infection, which is transmitted by the bite of the Aedes aegypti mosquito. The CZS clinical manifestations are broad and nonspecific, including microcephaly, subcortical calcifications, ocular alterations, congenital contractures, early hypertonia, and pyramidal as well as extrapyramidal symptoms. The ZIKV has gained great importance because it has affected a large percentage of the population worldwide during the last few years, despite the measures implemented by international organizations. The pathophysiology and non-vectorial transmission routes of the virus are still under study. The diagnosis is made upon suspicion of ZIKV infection, the patient's clinical manifestations, and it is confirmed by molecular laboratory tests demonstrating the presence of viral particles. Unfortunately, there is no specific treatment or vaccine for this condition; however, patients receive multidisciplinary care and constant monitoring. Therefore, the strategies that have been implemented are directed toward preventive measures and vector control.

Resumen En febrero de 2016, la Organización Mundial de la Salud declaró a la infección por virus Zika una emergencia de salud pública de importancia internacional por ser la causa del síndrome congénito por virus Zika. Este síndrome es considerado un patrón específico de defectos al nacimiento causados por la infección por virus Zika, que se transmite por la picadura del mosquito vector Aedes aegypti y cuyas manifestaciones clínicas son amplias e inespecíficas, entre las que destacan microcefalia, calcificaciones subcorticales, alteraciones oculares, contracturas congénitas, hipertonía temprana y síntomas de afectación piramidal y extrapiramidal. Este virus ha tomado gran importancia debido a que durante los últimos años ha afectado a un gran porcentaje de la población en todo el mundo, a pesar de las medidas implementadas por organizaciones internacionales. La fisiopatología y las vías de transmisión no vectorial de la infección aún siguen en estudio. El diagnóstico se realiza ante la sospecha por las manifestaciones clínicas del paciente, y se confirma mediante pruebas moleculares de laboratorio en las que se demuestre la presencia de partículas virales. Desafortunadamente, no existe aún un tratamiento ni una vacuna específica para este padecimiento; sin embargo, los pacientes reciben cuidados multidisciplinarios y monitorización constante. Las estrategias que se han implementado se dirigen hacia medidas preventivas de la infección y el control de los vectores.

Structural Determination of Lysine-Linked Cisplatin Complexes via IRMPD Action Spectroscopy: NNs and NO- Binding Modes of Lysine to Platinum Coexist.

Despite its success as an anticancer drug, cisplatin suffers from resistance and produces side effects. To overcome these limitations, amino-acid-linked cisplatin analogues have been investigated. Lysine-linked cisplatin, Lysplatin, (Lys)PtCl2, exhibited outstanding reactivity toward DNA and RNA that differs from that of cisplatin. To gain insight into its differing reactivity, the structure of Lysplatin is examined here using infrared multiple photon dissociation (IRMPD) action spectroscopy. To probe the influence of the local chemical environment on structure, the deprotonated and sodium-cationized Lysplatin complexes are examined. Electronic structure calculations are performed to explore possible modes of binding of Lys to Pt, their relative stabilities, and to predict their infrared spectra. Comparisons of the measured IRMPD and predicted IR spectra elucidate the structures contributing to the experimental spectra. Coexistence of two modes of binding of Lys to Pt is found where Lys binds via the backbone and side-chain amino nitrogen atoms, NNs, or to the backbone amino and carboxylate oxygen atoms, NO-. Glycine-linked cisplatin and arginine-linked cisplatin complexes have previously been found to bind only via the NO- binding mode. Present results suggest that the NNs binding conformers may be key to the outstanding reactivity of Lysplatin toward DNA and RNA.

Atypical presentation of Charcot-Marie-Tooth disease type 2Q by mutations on DHTKD1 and NTRK2 genes / Presentación atípica de enfermedad de Charcot-Marie-Tooth tipo 2Q por mutaciones en los genes DHTKD1 y NTRK2

Abstract Background: Charcot-Marie-Tooth disease type 2Q (CMT2Q) is a rare disorder (< 1/1,000,000 individuals worldwide) linked to chromosome 10p14 in the DHTKD1 gene. This phenotype is characterized by an adolescent or adulthood-onset, slowly progressive distal muscle weakness and symmetrical atrophy associated with reduced or absent deep tendon reflexes. Currently, only two familiar cases from China have been reported: one familiar case of eight individuals affected by isolated DHTKD1 gene mutation and one familiar case of two individuals affected by DHTKD1 gene mutation and GJB1 gene mutation. Case report: We present the case of a 10-year-old male patient with obesity, frequent falls, swollen legs and thighs, and pain in the lower and upper limbs. We performed the clinical evaluation and a clinical targeted exome test, which reported mutations on DHTKD1 y NTRK2 genes. Conclusions: Due to scientific and technological advances, genetic dysfunctions that can cause different diseases have been identified with greater sensitivity. Globally, this is the eleventh case reported of DHTKD1 gene mutation linked to CMT2Q. Moreover, this is the first case related to NTRK2 gene mutation (linked to obesity, hyperphagia, and delayed development). The patient showed an atypical CMT2Q phenotype additional to obesity. Therefore, we propose to study metabolic disorders linked to hereditary peripheral neuropathies.

Resumen Introducción: La enfermedad de Charcot-Marie-Tooth tipo 2Q (CMT2Q) es una alteración poco frecuente (< 1/1,000,000 habitantes en todo el mundo) condicionada por mutaciones en el gen DHTKD1, localizado en el cromosoma 10p14. El padecimiento inicia en la adolescencia o la edad adulta de manera lenta y progresiva, con debilidad muscular y atrofia distal simétrica, y afecta predominantemente las extremidades inferiores y los reflejos tendinosos profundos, que se encuentran reducidos o ausentes. Solo se ha reportado un caso familiar de ocho personas afectadas con la mutación aislada en el gen DHTKD1 y un caso familiar de dos personas afectadas con mutaciones en los genes DHTKD1 y GJB1, ambas familias de China. Caso clínico: Se presenta el caso de un paciente de sexo masculino de 10 años y 11 meses de edad con obesidad, caídas frecuentes, edema de miembros pélvicos y dolor en las extremidades inferiores y superiores. Se realizaron valoración clínica y estudio genético molecular de exoma dirigido, el cual reportó mutaciones en los genes DHTKD1 y NTRK2. Conclusiones: Gracias al avance científico y tecnológico se han podido identificar con mayor precisión las alteraciones genéticas causantes de diferentes enfermedades. Este es el undécimo caso reportado en el mundo de una mutación en el gen DHTKD1 asociada con la enfermedad de CMT2Q. También es el primer caso relacionado con una mutación del gen NTRK2 (asociada con obesidad, hiperfagia y retraso en el desarrollo). El paciente presentó un cuadro clínico atípico de enfermedad de CMT2Q agregado a obesidad. Por ello, se sugiere estudiar a fondo la conexión entre trastornos metabólicos y neuropatías periféricas hereditarias.

Diseño, elaboración y validación de un simulador realista y de bajo costo para exploración cardiaca / Design, assembly and validation of a low-cost, high-fidelity simulator for heart exploration

Resumen Introducción: La exploración cardiaca es una competencia clínica fundamental que requiere exposición o entrenamiento continuo. La baja disponibilidad y accesibilidad de pacientes con patología cardiaca constituye una barrera para adquirir esta competencia. Se han documentado inadecuadas habilidades de auscultación cardiaca en estudiantes de medicina, residentes y médicos graduados. Objetivo: Elaborar y validar un simulador de alta fidelidad y bajo costo para exploración cardiaca. Métodos: Se diseñó y elaboró un simulador para exploración cardiaca, realista y de bajo costo capaz de reproducir ruidos cardiacos normales. Posteriormente se realizó la validación del simulador por un grupo de expertos que emitieron su opinión de acuerdo con una escala tipo Likert. Resultados: El 94 % afirmó que el simulador motiva el aprendizaje de la exploración cardiaca y 92 % lo consideró un modelo realista; 91 % consideró que el simulador es una herramienta atractiva para fortalecer el aprendizaje y 98 % recomendó seguir utilizándolo. Conclusiones: El uso del simulador facilita la adquisición de competencias y estimula el aprendizaje en el estudiante, lo cual puede ser atribuido a la práctica deliberada, a un mayor tiempo de exposición y a la interacción cognitiva.

Abstract Introduction: Heart exploration is an essential clinical competence that requires continuous training and exposure. Low availability and accessibility to patients with heart disease constitutes a barrier to acquiring this competence. Inadequate cardiac auscultation skills in medical students, residents, and graduate physicians have been documented. Objective: To develop and validate a low-cost, high-fidelity simulator for heart exploration. Methods: A low-cost, high-fidelity heart examination simulator capable of reproducing normal cardiac sounds was designed and developed. Subsequently, the simulator was validated by a group of experts who gave their opinion according to a Likert scale. Results: Ninety-four percent agreed that the simulator motivates the learning of heart exploration, and 92 % considered it to be a realistic model; 91 % considered that the simulator is an attractive tool to reinforce learning and 98 % recommended its further use. Conclusions: The use of the simulator facilitates the acquisition of skills and stimulates learning in the student, which can be attributed to repeated practice, longer exposure time and cognitive interaction.

Strong Metal-Support Interactions between Copper and Iron Oxide during the High-Temperature Water-Gas Shift Reaction.

The commercial high-temperature water-gas shift (HT-WGS) catalyst consists of CuO-Cr2 O3 -Fe2 O3 , where Cu functions as a chemical promoter to increase the catalytic activity, but its promotion mechanism is poorly understood. In this work, a series of iron-based model catalysts were investigated with in situ or pseudo in situ characterization, steady-state WGS reaction, and density function theory (DFT) calculations. For the first time, a strong metal-support interaction (SMSI) between Cu and FeOx was directly observed. During the WGS reaction, a thin FeOx overlayer migrates onto the metallic Cu particles, creating a hybrid surface structure with Cu-FeOx interfaces. The synergistic interaction between Cu and FeOx not only stabilizes the Cu clusters, but also provides new catalytic active sites that facilitate CO adsorption, H2 O dissociation, and WGS reaction. These new fundamental insights can potentially guide the rational design of improved iron-based HT-WGS catalysts.

Elucidation of the Reaction Mechanism for High-Temperature Water Gas Shift over an Industrial-Type Copper-Chromium-Iron Oxide Catalyst.

The water gas shift (WGS) reaction is of paramount importance for the chemical industry, as it constitutes, coupled with methane reforming, the main industrial route to produce hydrogen. Copper-chromium-iron oxide-based catalysts have been widely used for the high-temperature WGS reaction industrially. The WGS reaction mechanism by the CuCrFeO x catalyst has been debated for years, mainly between a "redox" mechanism involving the participation of atomic oxygen from the catalyst and an "associative" mechanism proceeding via a surface formate-like intermediate. In the present work, advanced in situ characterization techniques (infrared spectroscopy, temperature-programmed surface reaction (TPSR), near-ambient pressure XPS (NAP-XPS), and inelastic neutron scattering (INS)) were applied to determine the nature of the catalyst surface and identify surface intermediate species under WGS reaction conditions. The surface of the CuCrFeO x catalyst is found to be dynamic and becomes partially reduced under WGS reaction conditions, forming metallic Cu nanoparticles on Fe3O4. Neither in situ IR not INS spectroscopy detect the presence of surface formate species during WGS. TPSR experiments demonstrate that the evolution of CO2 and H2 from the CO/H2O reactants follows different kinetics than the evolution of CO2 and H2 from HCOOH decomposition (molecule mimicking the associative mechanism). Steady-state isotopic transient kinetic analysis (SSITKA) (CO + H216O → CO + H218O) exhibited significant 16O/18O scrambling, characteristic of a redox mechanism. Computed activation energies for elementary steps for the redox and associative mechanism by density functional theory (DFT) simulations indicate that the redox mechanism is favored over the associative mechanism. The combined spectroscopic, computational, and kinetic evidence in the present study finally resolves the WGS reaction mechanism on the industrial-type high-temperature CuCrFeO x catalyst that is shown to proceed via the redox mechanism.

Enterocutaneous Fistula Coexisting with Enterovesical Fistula: A Rare Complication of Ovarian Cystectomy.

Enterocutaneous fistula is an abnormal communication between the intestine and the skin, while enterovesical fistula is an abnormal communication between the intestine and the bladder. Both are not usual complications of ovarian cystectomy. We present a patient with enterovesical fistula coexisting with enterocutaneous fistula following ovarian cystectomy. She is a 24- year-old lady with background immunosupression who presented to the National Obstetric Fistula Centre, Abakaliki South-East Nigeria with a history fecaluria, pneumaturia and passage of feculent fluid through the skin following ovarian cystectomy. Fistulogram was in keeping with rectovesical fistula. She was repaired in a single stage and made an uneventful recovery. Enterovesical fistula and enterocutaneus fistula are uncommon but possible complications of ovarian cystectomy.

Endoscopic Occlusion of Tracheoesophageal Fistula in Ventilated Patients Using an Amplatzer Septal Occluder.

Acquired tracheoesophageal fistula (TEF) is a challenging, life threatening condition. It most commonly appears in critically ill patients requiring prolonged mechanical ventilation, who cannot withstand open neck or chest surgery. An endoscopic technique could be better tolerated by these patients. We present our experience using a cardiac Amplatzer ASD septal occluder for an endoscopic TEF repair in ventilation-dependent patients. Two high risk patients underwent the procedure under general anesthesia and close respiratory monitoring. In one patient the device was inserted through the trachea and in the other through the esophagus. In both cases fistula closure was achieved for different periods of time allowing the patients a temporary relief of symptoms. The procedure was well tolerated by the patients, and no significant adverse effect documented. The technique was successful as a temporary solution for unstable patients with TEFs and should be considered as a treatment modality for similar patients.

Catalysis. Identification of molybdenum oxide nanostructures on zeolites for natural gas conversion.

Direct methane conversion into aromatic hydrocarbons over catalysts with molybdenum (Mo) nanostructures supported on shape-selective zeolites is a promising technology for natural gas liquefaction. We determined the identity and anchoring sites of the initial Mo structures in such catalysts as isolated oxide species with a single Mo atom on aluminum sites in the zeolite framework and on silicon sites on the zeolite external surface. During the reaction, the initial isolated Mo oxide species agglomerate and convert into carbided Mo nanoparticles. This process is reversible, and the initial isolated Mo oxide species can be restored by a treatment with gas-phase oxygen. Furthermore, the distribution of the Mo nanostructures can be controlled and catalytic performance can be fully restored, even enhanced, by adjusting the oxygen treatment.

Morbidity and mortality after major pulmonary resections in patients with locally advanced stage IIIA non-small cell lung carcinoma who underwent induction therapy.

BACKGROUND: The optimal treatment for patients with locally advanced stage IIIA non-small cell lung carcinoma (NSCLC) remains controversial, but induction therapy is increasingly used. The aim of this study was to evaluate mortality, morbidity, hospital stay and frequency of postoperative complications in stage IIIA NSCLC patients that underwent major pulmonary resections after neoadjuvant chemotherapy or chemoradiation. METHODS: We conducted a retrospective analysis of all patients who underwent major pulmonary resections after induction therapy for locally advanced NSCLC from October 2009 to February 2014. Forty-one patients were included in the study. RESULTS: Complete resection was achieved in 40 patients (97.5%). A complete pathologic response was seen in 10 patients (24.4%). Mean hospital stay was 17.7 days (ranged 5-129 days). Early (in-hospital) mortality occurred in 2.4% (one patient after bilobectomy), late (six months) mortality in 4.9% (two patients after right pneumonectomy and bilobectomy), and overall morbidity in 58.5% (24 patients). Postoperative complications included: bronchopleural fistula (BPF) with empyema - three patients, empyema without BPF - five patients, air leak - eight patients, atrial fibrillation - eight patients, pneumonia - eight patients, and lobar atelectasis - four patients. CONCLUSION: Following neoadjuvant therapy for stage IIIA NSCLC, pneumonectomy can be performed with low early and late mortality (0% and 5.8%, respectively), bilobectomy is a high risk operation (16.7% early and 16.7% late mortality); and lobectomy a low risk operation (0% early and late mortality). The need for major pulmonary resections should not be a reason to exclude patients from a potentially curative procedure if it can be performed with acceptable morbidity and mortality rates at an experienced medical centre.

Video-assisted thoracic surgery lobectomy versus lobectomy by thoracotomy for lung cancer: pilot study.

OBJECTIVE: Video-assisted thoracic surgery lobectomy (VATS-L) has become accepted as a safe and effective procedure to treat early-stage non-small cell lung carcinoma (NSCLC). However, the advantages of VATS-L compared with lobectomy by thoracotomy (TL) remain controversial. The aim of this study was to compare the outcomes of patients who underwent VATS-L with those who underwent TL. METHODS: We studied 103 patients who underwent surgery for operable NSCLC between October 2009 and March 2012. All operations were performed by a single surgeon. The inclusion and exclusion criteria for VATS-L and TL were formulated before the study was initiated. Data on age, sex, preoperative comorbidities, intraoperative and postoperative complications, hospital stay, morbidity, mortality, and other characteristics were recorded preoperatively, in real time intraoperatively, and during hospitalization and were statistically compared. Comorbidities were scaled according to the Charlson Comorbidity Index, and propensity scores between the patients who underwent TL and VATS-L were compared. RESULTS: Sixty-three VATS-L operations and 40 TL operations were performed. There were no postoperative complications in 39 patients (61.9%) who underwent VATS-L compared with 25 patients (62.5%) who underwent TL. The patients who underwent TL were significantly younger than the patients who underwent VATS-L (mean ± SD, 64.7 ± 12.6 vs 70.9 ± 8.4; P = 0.003). Hospital stay was not found to be related to the type of surgery (mean ± SD, 8.43 ± 3.15 days vs 8.32 ± 4.13 days; P = 0.888). There were no significant differences when comparing postoperative complications. CONCLUSIONS: Our initial data suggest that VATS-L is a safe procedure in patients with resectable IA/IB NSCLC and may be the preferred strategy for treatment of the older patient population.

Endobronchial closure of recurrent bronchopleural and tracheopleural fistulae by two amplatzer devices.

We present a case of right pneumonectomy after induction chemotherapy complicated by a large bronchopleural fistula and empyema two weeks after surgery. The patient was treated surgically by transsternal transpericardial bronchopleural fistula closure and open window thoracoplasty. Thereafter, two new fistulae developed, one in the right main bronchial stump and one in the accessory tracheal bronchus. The two Amplatzer devices that were originally designed for transcatheter closure of cardiac defects were successfully used for closure of the bronchopleural fistulae.

Cisplatin effects on rhythmic functions of mice: strain and tissue dependence.

The competence to preserve the optimal timing relationships between rhythmic variables enables adaptation of mammals to alternate environmental conditions. The capability to re-entrain depends on genetic factors and the nature of imposed time cues. In the present study, the authors examined in rodent models, following a cancer chronochemotherapy, cisplatin (CP), the rhythm patterns of locomotor activity and of a few biochemical variables (alkaline phosphatase and creatinine phosphokinase in kidney tissue and plasma, kidney urea nitrogen, and white blood cell count). Males of two inbred mice strains, BALB/c and c57Bl/6J, received 10 consecutive daily intraperitoneal (i.p.) injections of either saline or CP at zeitgeber time 22 (ZT22). CP administration altered the rhythms of each examined function in both strains. The type and extent of the changes varied among variables, tissues/plasma, and mouse strain. Yet, the effect of CP was not detected on all parameters, but only in ∼60% of them. In addition, in the majority of the studied parameters, BALB/c and c57Bl/6J mice differed in their response to CP. The temporal parameters of period and peak time were more affected by CP than were the level ones of mesor (time series mean) and amplitude of variation. This observation may indicate the involvement of independent pathways of action upon each of the rhythm parameter sets. As a result, the rhythm phenotype of each function was modified and novel timing relationships were shaped. The results show that the circadian systems of BALB/c and c57Bl/6J mice failed to re-entrain after cessation of CP injections (tested on the first day following the 10 d course of CP administration), pointing to a direct effect of the medication on the tissues. The findings imply that optimal chemotherapeutic protocols should be tailored individually, according to the current temporal order rather than administered at a fixed predetermined circadian time. Further studies are necessary to determine which variables and rhythmic parameters could be useful to determine the optimal timing of chronochemotherapy.

Assessment of tobacco dependence in waterpipe smokers in Egypt.

SETTING: Waterpipe smoking is increasing worldwide. Nevertheless, little is known about nicotine dependence in tobacco smokers who use waterpipes. OBJECTIVE: To assess evidence of dependence among non-cigarette smoking waterpipe smokers in Egypt. METHODS: A total of 154 male exclusive current waterpipe smokers were enrolled for the present study. We adapted the Fagerström test for nicotine dependence and the Reasons for Smoking (RFS) scales and related these to smoking behavior. RESULTS: The mean age of the subjects was 47 ± 14 years, the mean age at smoking initiation was 22 ± 9 years, and average daily consumption was 4 ± 8 hagars (tobacco units). The time to the first smoke of the day (P < 0.001), smoking even when ill (P = 0.003), time to tobacco craving (P < 0.001), and hating to give up the first smoke of the day (P = 0.033) were each significantly associated with the number of hagars smoked per day. The RFS subscales of addictive smoking, smoking to relieve negative affect, and smoking for stimulation were also associated with these variables. CONCLUSION: The overall findings suggest that waterpipe smokers exhibit many of the same features of nicotine dependency attributed to cigarette smokers.

Evaluación de la capacidad y percepción de autocuidado del adulto mayor en la comunidad / Assessment of the capability and perception of self-care of elderly in community

Medir salud en el paciente anciano resulta complejo, pues es medir la resultante de diversas variables de carácter biológico, psicológico y social, por lo que la salud del anciano debe medirse en correspondencia con su funcionabilidad. Motivado por esto se realizó un estudio descriptivo transversal en el municipio Holguín con el objetivo de evaluar la capacidad y percepción de autocuidado del Adulto Mayor en la comunidad. De un universo de 354 ancianos de 3 consultorios, se seleccionaron 195, a los cuales se les aplicó un Instrumento diseñado al efecto para medir su nivel de autocuidado. Los resultados arrojaron que el 50,5 por ciento de los hombres y el 43,3 por ciento de las mujeres no se cuida adecuadamente, existe un déficit de autocuidado cognoscitivo-perceptivo en el 46,7 por ciento, un 9,8 por ciento tienen déficit parcial y 5,6 por ciento déficit total. De los 121 pacientes cuyo nivel de autocuidado es inadecuado el 75,2 por ciento son independientes y el 63,6 por ciento perciben su estado de salud aparentemente sano, concluyéndose que no obstante la gran mayoría de los adultos mayores estudiados ser independientes para realizar las actividades de la vida diaria, estos no desarrollan adecuadamente sus capacidades de autocuidado, por lo que el grado funcional independiente es una condición necesaria pero no suficiente para un buen autocuidado, los adultos mayores que perciben algún riesgo para su salud se cuidan más que los que se perciben sanos. El instrumento aplicado define la actividad de autocuidado en las personas mayores, recomendándose su introducción en la evaluación gerontológica en la Atención Primaria de Salud(AU)

To measure health in the old patient is complex, because it is to measure the resultant of diverse variables of biological, psychological and social character, for what the health in old man should be measured in correspondence with their functional state. Motivated for this reason was carried out a traverse descriptive study in the municipality Holguin, with the objective of evaluating the capacity and perception of self-care of the old men in the community. Of an universe of 354 elderly people of 3 clinics, 195 were selected, to which were applied an Instrument designed to the effect to measure their level of self-care. The results indicated that 50,5 percent of the men and 43,3 percent of the women don't their care appropriately, a deficit of cognitive-perceptive self-care exists in 46,7 percent, 9,8 percent has partial deficit and 5,6 percent total deficit. Of the 121 patients whose level of self-care is inadequate, 75,2 percent is independent and 63,6 percent perceives its seemingly healthy state of health, being concluded that nevertheless the great majority of the studied old men to be independent to carry out the activities of the daily life, they don't develop its capacities of self-care appropriately, for what the independent functional degree is a necessary but not enough condition for a good self-care, the elderly people that perceive some risk for its health take care more than those that are perceived healthy. The applied instrument defines the activity of self-care in the study patients, being recommended its introduction in the geriatric evaluation in the Primary Attention of Health(AU)

Possible linkage between the ability to change the period (tau) of the prolactin and cortisol rhythms in women and breast cancer risk.

The 24 h profiles of plasma hormone concentrations are rhythmic. The circadian period (tau) changes in development, with seasons, and in women with different stages of the menstrual cycle. It is known that the rhythms of prolactin and cortisol are sensitive to environmental time cues, such as changes in day length and phase; however, the importance of these changes is not yet understood. This study investigates whether there is a relation between the ability of a subject to respond to external cues that are associated with seasonal changes causing alteration of the rhythm's periods in cortisol and prolactin and the epidemiologically determined susceptibility to breast cancer. It is shown that the rhythmic output pattern of prolactin and cortisol in vivo is generated by more than one oscillator and structured by more than one rhythmic component. Each cohort of American women, classified on an epidemiologic basis as high risk (HR) or low risk (LR) to develop breast cancer, expresses different rhythmic output patterns of both variables, suggesting that the genetic background as defined by the risk state is related to differences in the circadian time structure, including the ability of the subject to change the rhythm's tau. The LR cohort exhibited a statistically significant change between seasons in the rhythm's tau of both the prolactin and cortisol patterns. In contrast, the HR cohort showed no change in the rhythm's tau between seasons for prolactin and cortisol patterns. These results show that in human beings, the presence of a circannual rhythm in the circadian time structure or the ability to adapt the circadian rhythmic pattern of these variables to external cues, such as seasons, is related to the partly genetically determined risk state to develop breast cancer and may be of importance for human health.