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INTRODUCTION: This study aimed to evaluate the feasibility of molecular point-of-care testing for STIs, the prevalence of STIs and associated factors, and testing and treatment uptake among street-based female sex workers (FSWs) attending a mobile harm reduction unit in Madrid, Spain. METHODS: This was a prospective, longitudinal study. From August 15th to December 6th, 2022, participants were screened for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis using molecular testing (Xpert) on self-collected urine samples at a mobile harm reduction unit. Additionally, rapid tests were used to screen participants for HIV, hepatitis C virus (HCV), and syphilis. On-site same-day results and treatment for those infected were offered. RESULTS: Among 77 FSWs included the median age was 40 (range, 33-48), 64 % were homeless, and 84 % reported drug use in the past six months. Four participants self-reported having HIV, of whom all were on antiretroviral therapy, and 14 (18 %) had HCV antibodies, including three with current infection. The prevalence of at least one STI was 66 %. When categorized by type of STI, the prevalences were as follows: 15 % for CT, 15 % for NG, 51 % for TV, and 21 % for syphilis. Notably, the prevalence of STIs was higher among FSW with recent drug use, with no cases of CT or NG detected among FSWs who did not recently use drugs. In adjusted analysis, drug use was associated an increased odds of having an STI (adjusted odds ratio, 10.47; 95 % CI: 1.67-65.42). All participants consented to screening, and all but one received on-site result-based linkage to treatment. CONCLUSIONS: This study demonstrates the feasibility, high STI prevalence, and high linkage to testing and treatment following point-of-care molecular testing among street-based FSWs who have recently used drugs in Madrid, Spain.
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Infecções por Chlamydia , Gonorreia , Infecções por HIV , Profissionais do Sexo , Infecções Sexualmente Transmissíveis , Sífilis , Feminino , Humanos , Adulto , Sífilis/diagnóstico , Sífilis/epidemiologia , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Redução do Dano , Espanha/epidemiologia , Estudos Prospectivos , Estudos Longitudinais , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/terapia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Testes Imediatos , PrevalênciaRESUMO
In this work, it is presented a first approach of a mathematical and kinetic analysis for improving the decoloration and further degradation process of an azo dye named acid red 27 (AR27), by means of a novel microbial consortium formed by the fungus Trametes versicolor and the bacterium Pseudomonas putida. A multivariate analysis was carried out by simulating scenarios with different operating conditions and developing a specific mathematical model based on kinetic equations describing all stages of the biological process, from microbial growth and substrate consuming to decoloration and degradation of intermediate compounds. Additionally, a sensitivity analysis was performed by using a factorial design and the Response Surface Method (RSM), for determining individual and interactive effects of variables like, initial glucose concentration, initial dye concentration and the moment in time for bacterial inoculation, on response variables assessed in terms of the minimum time for: full decoloration of AR27 (R1 = 2.375 days); maximum production of aromatic metabolites (R2 = 1.575 days); and full depletion of aromatic metabolites (R3 = 12.9 days). Using RSM the following conditions improved the biological process, being: an initial glucose concentration of 20 g l-1, an initial AR27 concentration of 0.2 g l-1 and an inoculation moment in time of P. putida at day 1. The mathematical model is a feasible tool for describing AR27 decoloration and its further degradation by the microbial consortium of T. versicolor and P. putida, this model will also work as a mathematical basis for designing novel bio-reaction systems than can operate with the same principle of the described consortium.
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The roe deer (Capreolus capreolus) has been identified as an intermediate host for six known Sarcocystis species, S. capreolicanis, S. entzerothi, S. gracilis, S. linearis, S. oviformis, and S. silva. In this study, we identified Sarcocystis species in the diaphragm and tongue muscles from the Lithuanian and Spanish roe deer, respectively, on the basis of a microscopic examination and DNA analysis. A total of 43 and 27 sarcocysts were isolated and characterized from the Lithuanian and Spanish roe deer, respectively. Overall six Sarcocystis species were identified in roe deer from Lithuania, and only three of them, S. gracilis, S. linearis, and S. silva were found to have infecting animals from Spain. The current paper represents first molecular results of Sarcocystis species in the Spanish roe deer. Furthermore, transmission electron microscopy examination revealed specific wall structure of sarcocysts studied, S. linearis was characterized by ribbon-like villar protrusions (vp) (type 8a), and S. oviformis was distinguished by elongated vp resembling spades or mushroom-like structures (type 39). Based on 18S rDNA and cox1 sequences, Sarcocystis species from the roe deer showed considerable intraspecific genetic variability. However, similar values of intraspecific genetic variation were estimated at both genes analysed. The highest variability was observed for S. capreolicanis and S. linearis in both genes and for S. silva at cox1. Consequently, the level of genetic variability of Sarcocystis from the roe deer varied depending on species rather than on gene analysed or geographical area.
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Cervos/parasitologia , Sarcocystis/classificação , Sarcocistose/epidemiologia , Sarcocistose/veterinária , Animais , Ciclo-Oxigenase 1/genética , DNA Ribossômico/genética , Diafragma/parasitologia , Lituânia/epidemiologia , Microscopia Eletrônica de Transmissão , Filogenia , RNA Ribossômico 18S/genética , Sarcocystis/genética , Sarcocystis/isolamento & purificação , Espanha/epidemiologia , Língua/parasitologiaRESUMO
Synapses loss during aging has been related to decreased neuronal excitability and reduced electrophysiological activity in the nervous system, as well as to increased brain damage. Those physiological and biochemical alterations have been related to the oxidative stress increase associated with old age. The main substrate of lipid peroxidation (LPX) in the central and peripheral nervous systems are the myelin sheaths, and their damage generates a delayed nerve conduction velocity. However, studies in which the neural conduction velocity is related to changes in the redox state are still lacking. Therefore, our aim was to correlate the sensory neural pathways delay in healthy geriatric Rhesus monkeys (Macaca mulatta) with the oxidative stress associated with physiological aging. Twenty-four monkeys were divided into four groups according to age and gender. Auditory, visual, and somatosensory evoked potentials were obtained. Superoxide dismutase, catalase, and glutathione peroxidase enzymatic activity, as well as LPX, were determined from blood samples. Our results showed significant differences between the older and younger age groups in all neural generators of the different sensory pathways evaluated, along with an increase in LPX and the antioxidant enzymatic activities. It suggests that, even though the enzymatic activity was found to be higher in older monkeys, probably as a compensatory effect, it was not enough to avoid LPX damage and the declined electric activity associated with age.
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Envelhecimento/fisiologia , Potenciais Evocados Auditivos/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Potenciais Evocados Visuais/fisiologia , Peroxidação de Lipídeos/fisiologia , Sistema Nervoso , Animais , Feminino , Glutationa Peroxidase/metabolismo , Macaca mulatta , Masculino , Sistema Nervoso/enzimologia , Sistema Nervoso/metabolismo , Sistema Nervoso/fisiopatologia , Condução Nervosa/fisiologia , Oxirredução , Estresse Oxidativo , Sensação/fisiologia , Superóxido Dismutase/metabolismoRESUMO
Se presenta el caso clínico de una paciente de 63 años, con indicación de tiroidectomía total, a causa de un bocio multinodular con infiltrado neoplásico folicular. La evolución posquirúrgica fue tórpida y se caracterizó por la presencia de insuficiencia cardiaca aguda, hepatomegalia, neuropatía periférica y equimosis periorbitaria, condiciones clínicas sugerentes de amiloidosis, la que fue confirmada por medio de estudios como amiloidosis de cadenas ligeras (AL).
We present the clinical case of a 63-year-old patient, with indication of total thyroidec-tomy, due to a multinodular goiter with a follicular neoplastic infiltrate. Postoperative evolution was torpid and was characterized by the presence of acute heart failure, hepatomegaly, peripheral neuropathy and periorbital ecchymosis, clinical conditions suggestive of amyloidosis, which was confirmed by studies such as amyloidosis of light chains (AL).
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Humanos , Feminino , Pessoa de Meia-Idade , Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Amiloidose/diagnóstico , Tireoidectomia , Biópsia , Vermelho Congo , Amiloidose/patologia , NeoplasiasRESUMO
El manejo del dolor articular ofrece para la población afectada novedosos suplementos nutricionales que incluyen el colágeno, y cuya extracción es desde variadas fuentes de origen animal, no así de vegetales. Esta revisión tiene como objetivo aclarar qué es el colágeno, su constitución estructural molecular, el rol que cumple en nues-tro organismo y revisar las indicaciones propuestas por la literatura, tanto para la profilaxis como el tratamiento de cuadros reumatológicos de alta prevalencia o impacto funcional, como son Artrosis, Artritis Reumatoidea y Osteoporosis.
Novel nutritional supplements for the management of joint pain have been made available to the population, including collagen, which can not be extracted from plant products, but from a variety of animal sources. This review aims to clarify what it is collagen, the molecular structures that constitute it, the determined role they play in our body and review the indications that the literature proposes both in prophylaxis and treatment, for high prevalence rheumatologic or functional impact, such as osteoarthritis, rheumatoid arthritis and osteoporosis.
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Humanos , Doenças Reumáticas/terapia , Colágeno/uso terapêutico , Osteoartrite/terapia , Osteoporose/terapia , Artrite Reumatoide/terapia , Matriz ExtracelularRESUMO
Introducción: El prolapso genital impacta negativamente la calidad de vida y autoimagen de la mujer. Rutinariamente indicamos la colpoperineocleisis de Labhardt a pacientes de edad avanzada y sin actividad sexual. Objetivo: Evaluar los resultados con esta técnica e identificar posibles factores de riesgo que predigan la falla. Métodos: Análisis retrospectivo de pacientes tratadas con la técnica entre los años 2008-2010. Se realizó análisis univariado y multivariado para identificar factores de riesgo asociados a la falla y se construyeron curvas libre de falla anatómica a fin de evaluar la durabilidad. Resultados: 68 pacientes cumplieron los criterios de inclusión. La edad promedio fue 71,9 +/- 5,7 años; 95,6 por ciento fueron clasificadas en etapa III o IV según POP-Q. El tiempo operatorio fue de 54 +/- 20 minutos. Seguimiento promedio de 21 meses; la tasa de recidiva anatómica fue de 14,7 por ciento. La tasa de incontinencia de orina de esfuerzo (IOE) de novo fue de 5,9 por ciento. El análisis univariado identificó como factor predictor de recidiva el flujo vaginal posoperatorio; en análisis multivariado de Cox, esa condición mantuvo significancia estadística (OR 6,3). Se identificó como factor de riesgo el no acatamiento de la técnica quirúrgica (OR 7,2). Conclusión: La colpoperineocleisis de Labhardt es una técnica segura, con baja tasa de complicaciones, una tasa de recurrencia aceptable y baja tasa de IOE de novo. Pilar del éxito es evitar la infección y respetar la técnica quirúrgica. Es necesario estudios comparativos con otras técnicas oclusivas, como también evaluar el rol de la infección como causa de falla de la técnica.
Introduction: Genital prolapse affects up to 50 percent of multiparous women, impacting their quality of life and self-image. At our Institution Labhardt's colpoperineocleisis is usually proposed to older patients, without sexual activity, regardless the type or grade of prolapse. Objective: To evaluate the results with this technique and identify potential risk factors predicting the failure. Methods: Analysis of a retrospective cohort of patients treated with this technique between 2008 and 2010. Univariate and multivariate analysis were carried out to identify risk factors and failure-free curves were built to estimate durability. Results: 68 patients met the inclusion criteria. Average age was 71.9 +/- 5.7 years; 95.6 percent of patients were classified as stage III or IV based on POP-Q system. Operative time was 54 +/- 20 min. At 21 months of follow-up, recurrence rate was 14.7 percent. De novo stress urine incontinence (SUI) was diagnosed in 5.9 percent of patients. In univariate analysis, post operative vaginal discharge was identified as predicting factor for defect recurrence. In Cox analysis, this condition remained significant (OR 6.3), In addition, failure to observe the surgical technique was also identified as risk factor for defect recurrence (OR 7.2). Conclusion: Labhardt 's colpoperineocleisis is a safe technique, with low complication rate, acceptable recurrence rate, and low de novo SUI rate. Mainstay for success is to avoid infection and observe the surgical technique. Comparative studies with other occlusive techniques might be carried out, as well as exploring the role of infection as predisposing condition for failure.
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Humanos , Feminino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos em Ginecologia/métodos , Prolapso de Órgão Pélvico/cirurgia , Análise Multivariada , Qualidade de Vida , Estudos Retrospectivos , Seguimentos , Recidiva , Resultado do Tratamento , Satisfação do Paciente , Intervalo Livre de DoençaRESUMO
The partition function of all classical spin models, including all discrete standard statistical models and all Abelian discrete lattice gauge theories (LGTs), is expressed as a special instance of the partition function of the 4D Z2 LGT. This unifies all classical spin models with apparently very different features in a single complete model. This result is applied to establish a new method to compute the mean-field theory of Abelian discrete LGTs with d > or = 4, and to show that computing the partition function of the 4D Z2 LGT is computationally hard (#P hard). The 4D Z2 LGT is also proved to be approximately complete for Abelian continuous models. The proof uses techniques from quantum information.
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The endocannabinoid system is a neuromodulatory system which controls the release of multiple neurotransmitters, including glutamate and both, the endocannabinoid and glutamatergic systems, have been implicated in alcohol relapse. Cannabinoid agonists induce an increase in relapse-like drinking whereas glutamate receptor antagonists could prevent it. Here we hypothesize that cannabinoid-induced increases in relapse-like alcohol drinking could be mediated by glutamatergic N-methyl-d-aspartate (NMDA) receptors. To test this hypothesis, Wistar rats with a background of alcohol operant self-administration were treated with the cannabinoid receptor agonist (R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl), pyrrolo [1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone mesylate (WIN 55.212-2, WIN) (2.0 mg/kg) during periods of alcohol deprivation. For five consecutive days, 30 min before the reintroduction of alcohol, rats were injected with the NMDA/glycine receptor antagonist 7-chloro-4-hydroxy-3-(3-phenoxy)phenylquinolin-2-[1H]-one (L-701) (1.25-5.0 mg/kg) and alcohol reinforcement was evaluated. Our results clearly show that L-701 prevented the cannabinoid-induced increase in relapse-like drinking in a dose-dependent manner, whereas L-701 alone, in the absence of WIN treatment, did not significantly alter alcohol intake. The potentiation of relapse-like drinking induced by WIN is not caused by nonspecific anxiogenic effects, since no effect was observed in the elevated-plus maze test. These alcohol-related behaviors are linked to differential changes in CNR1 and NR1 subunit mRNA transcripts. In WIN-treated rats, an increase in CNR1 transcript levels was observed in the hypothalamus and striatum, whereas in the amygdala and anterior cingulate cortex, brain regions involved in emotional processing, a decrease was observed. Interestingly, such changes were blocked after L-701 treatment. Finally, WIN treatment also caused a reduction in NR1 mRNA levels in the amygdala. In conclusion, pharmacological inactivation of the glycine-binding site of NMDA receptors may control cannabinoid-induced relapse-like drinking, which is associated with altered expression of CNR1 and NR1 gene expression as observed after WIN treatment.
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Consumo de Bebidas Alcoólicas/prevenção & controle , Alcoolismo/fisiopatologia , Canabinoides/efeitos adversos , Glicina/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Síndrome de Abstinência a Substâncias/prevenção & controle , Consumo de Bebidas Alcoólicas/fisiopatologia , Alcoolismo/metabolismo , Animais , Benzoxazinas/farmacologia , Sítios de Ligação/efeitos dos fármacos , Canabinoides/agonistas , Condicionamento Operante/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Etanol/administração & dosagem , Etanol/efeitos adversos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Morfolinas/farmacologia , Naftalenos/farmacologia , Quinolonas/farmacologia , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/genética , Receptor CB1 de Canabinoide/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Autoadministração , Síndrome de Abstinência a Substâncias/fisiopatologiaRESUMO
Tobacco and alcohol are highly co-abused by humans. Most experimental studies have evaluated ethanol consumption in animals exposed concomitantly to nicotine. However, little is known regarding the effects of nicotine administered during periods of alcohol deprivation. In the present study, adult male Wistar rats with an extended background of operant self-administration of ethanol were alcohol-deprived and treated with nicotine (0.1, 0.2, 0.4 and 0.8 mg/kg) or saline during five consecutive days in one chamber of a place conditioning apparatus. Nicotine-induced changes in locomotion were monitored daily, whereas the expression of place conditioning was studied the day after the last nicotine injection. Forty-eight hours after testing for conditioning, the animals resumed operant self-administration of ethanol and their alcohol intake was evaluated during the next 14 days. We observed that alcohol consumption was increased in animals treated with nicotine at doses of 0.2, 0.4 and 0.8 mg/kg but not in animals treated with the dose of 0.1 mg/kg or saline. Additionally, the dose of 0.8 mg/kg of nicotine not only induced persistent changes in alcohol self-administration but also produced conditioned place aversion and depressed locomotor activity. These results indicate that nicotine administration during the ethanol deprivation period can exacerbate the maintenance of alcohol consumption.
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Depressores do Sistema Nervoso Central/farmacologia , Condicionamento Operante/efeitos dos fármacos , Etanol/farmacologia , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Animais , Relação Dose-Resposta a Droga , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar , Reforço Psicológico , Recompensa , Autoadministração , Síndrome de Abstinência a Substâncias/psicologiaRESUMO
Biosolids and composted municipal solid wastes were surface-applied (0 and 80 Mg ha(-1)) to a degraded soil in a semi-arid environment to determine their effects on the quantity and quality of run-off water. Three and 4 years after application, a simulated rainfall was performed (intensity=942.5 ml min(-1) and kinetic energy=3.92 J m(-2)) on 0.078 m(2) plots using a portable rainfall simulator. The run-off from the different treatment plots was collected and analysed. The type of treatment was highly related to infiltration, run-off and sediment production. The biosolid-treated plots showed the minimum value of total run-off, maximum time to the beginning of run-off and maximum run-off ratio (the relationship between total rainfall and run-off). The MSW-treated plots showed values intermediate between biosolid-treated plots and control plots. Soil losses were also closely related to treatment type. Control plots showed the maximum sediment yield, MSW-treated plots showed intermediate values, and biosolid plots the minimum values for washout. The concentrations of NH(4)-N and PO(4)-P in the run-off water were significantly higher in the treated plots than in control plots. The highest PO(4)-P value, 0.73 mg l(-1), was obtained in the soil treated with biosolids; NO(3)-N concentration also increased significantly with respect to the control and MSW treatments. NH(4)-N concentrations of 15.6 and 15.0 mg l(-1) were recorded in the soils treated with biosolids and MSW, respectively, values approximately five times higher than those obtained in run-off water from untreated soil. However, the concentrations of all these constituents were lower than threshold limits cited in water quality standards for agricultural use. With the exception of Cu, all trace metals analysed in the run-off water were below detection limits.
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Clima Desértico , Ecossistema , Eliminação de Resíduos , Poluentes do Solo/análise , Poluentes da Água/análise , Conservação dos Recursos Naturais , Cinética , Nitrogênio/análise , Fosfatos/análise , Chuva , Oligoelementos/análise , Movimentos da ÁguaRESUMO
Many soils of the Mediterranean region with a semiarid climate are subjected to progressive degradation as a result of water erosion. Biosolids and municipal solid wastes (MSW) were surface-applied once at three rates (40, 80, and 120 Mg ha(-1)) to different plots in a degraded semiarid ecosystem. The study was conducted to determine the effects of such applications on soil chemical properties and native vegetation over a three-year period. Soil N, P, and K initially increased with increasing biowaste application rates, but then decreased over time. Levels of Zn and Cu were higher in MSW than biosolid-treated plots, and increased in both years after application. Concentrations of soil Cd, Pb, Ni, and Cr did not change as a result of biowaste amendment in the study period. The growth of native plants was enhanced by the addition of biowastes. Total plant canopy and plant biomass increased significantly and remained higher in all treatments than in the control plot over the three-year period. The species richness of native plants decreased with increasing biowaste rates. Differences in the development of native plant communities between treatments were observed, and were more remarkable three years after biowaste application. Tissue N, P, K, Zn, and Cu levels increased with the biowaste application rate, but concentrations of tissue Pb, Cd, Ni, and Cr did not increase significantly. Biowastes applied at the rate of 80 Mg ha(-1) gave rise to the most favorable soil and native vegetation results while avoiding environmental risks.
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Clima Desértico , Ecossistema , Metais Pesados/análise , Eliminação de Resíduos , Poluentes do Solo/análise , Agricultura , Biomassa , Monitoramento Ambiental , Região do Mediterrâneo , Plantas/química , Medição de RiscoRESUMO
El uso sistemático de la mamografía y ultrasonido ha incrementado el diagnóstico de lesiones mamarias no palpables y con ello, la indicación de biopsia. Material y Método: Presentamos nuestra experiencia en 315 biopsias excisionales de lesiones mamarias ocultas con localización preoperatoria. Utilizamos la mamografía en el 83,8% y el ultrasonido en el 10,5% de los casos para posicionar una guía metálica; en el 5,7% se realizó marcación sobre la piel, guiada por ultrasonido. Resultados: Obtuvimos 21,2% de tumores malignos, 17,5% de hiperplasia atípica y 60,3% de patología benigna. No obtuvimos una muestra adecuada en el 1% de los casos (3 pacientes). Discusión: La incidencia de 21,2% de patología maligna es consistente con los hallazgos de la literatura general (entre 20 y 30%). Si incluimos la hiperplasia atípica, como patología premaligna, los resultados positivos alcanzan el 38,7%. Más de la mitad de las lesiones son de etiología benigna. Es necesario mejorar tanto la sensibilidad como la especificidad de los métodos diagnósticos, para evitar cirugías innecesarias.
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Feminino , Neoplasias da Mama , Doenças Mamárias/cirurgia , Doenças Mamárias/diagnóstico , Ultrassonografia Mamária , PalpaçãoRESUMO
We report the synthesis and voltamperometric reduction of 5H-benzo[b]carbazole-6,11-dione (BCD) and its 2-R-substituted derivatives (R = -OMe, -Me, -COMe, -CF(3)). The electrochemical behavior of BCDs was compared to that of the 2-[(R-phenyl)amine]-1,4-naphthalenediones (PANs) previously studied. Like PANs, BCDs exhibit two reduction waves in acetonitrile. The first reduction step for the BCDs represents formation of the radical anion, and the half-wave potential (E(1/2)) values for this step are less negative than for that of the PANs. The second reduction wave, corresponding to the formation of dianion hydroquinone, has E(1/2) values that shift to more negative potentials. A good linear Hammett-Zuman (E(1/2) vs sigma(p)) relationship, similar to that for the PAN series, was also obtained for the BCDs. However, unlike the PANs, in the BCDs, the first reduction wave was more susceptible to the effect of the substituent groups than was the second wave, suggesting that the ordering of the two successive one-electron reductions in BCDs is opposite that in PANs. This is explained by the fact that the electron delocalizations in the two systems are different; in the case of BCDs there is an extra aromatic indole ring, which resists loss of its aromatic character. The electronic structures of BCD compounds were, therefore, investigated within the framework of the density functional theory, using the B3LYP hybrid functional with a double zeta split valence basis set. Our theoretical calculations show that the O(1).H-N hydrogen bond, analogous to that previously described for the PAN series, is not observed in the BCDs. Laplacians of the critical points (nabla(2)rho) and the natural charges for the C-O bonds indicate that the first reduction wave for the BCDs corresponds to the C(4)-O(2) carbonyl, while in the PAN series the first one-electron transfer occurred at the C(1)-O(1) carbonyl. Natural bond orbital analysis showed that, in all the BCDs, the lowest unoccupied molecular orbital (LUMO) is located at C(4), whereas for the PANs, the LUMO is found at C(1). The good correlation between the LUMO energy values and the E(1/2) potentials (wave I) established that the first one-electron addition takes place at the LUMO. Analysis of the molecular geometry confirmed that, in both series of compounds, the effect of the substituent groups is mainly on the C(4)-O(2) carbonyl. These results explain the fact that reduction of the C(4)-O(2) carbonyl (voltammetric wave II in the PANs and voltammetric wave I in the BCDs) is more susceptible to the effect of the substituent groups than is reduction of the C(1)-O(1) carbonyl (wave I in the PANs and wave II in the BCDs).
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Carbazóis/química , Naftoquinonas/química , Carbazóis/síntese química , Carbazóis/farmacologia , Eletroquímica , Cinética , Modelos Químicos , Naftoquinonas/síntese química , Naftoquinonas/farmacologia , Oxirredução , Relação Estrutura-AtividadeRESUMO
Thirteen C(6) para-substituted anilinebenzoquinones derived from perezone (PZ) (2-(1,5-dimethyl-4-hexenyl)-3-hydroxy-5-methyl-1,4-benzoquinone) were prepared to analyze the effect of the substituents on quinone electronic properties. The effect of a hydrogen bond between the alpha-hydroxy and carbonyl C(4)-O(4) groups was determined in perezone derivatives by substituting electron-donor and electron-acceptor groups such as -OMe, -Me, -Br, and -CN and comparing the -OH (APZs) and -OMe (APZms) derivatives. Reduction potentials of these compounds were measured using cyclic voltammetry in anhydrous acetonitrile. The typical behavior of quinones, with or without alpha-phenolic protons, in an aprotic medium was not observed for APZs due to the presence of coupled, self-protonation reactions. The self-protonation process gives rise to an initial wave, corresponding to the irreversible reduction reaction of quinone (HQ) to hydroquinone (HQH(2)), and to a second electron transfer, attributed to the reversible reduction of perezonate (Q(-)) formed during the self-protonation process. This reaction is favored by the acidity of the alpha-OH located at the quinone ring. To control the coupled chemical reaction, we considered both methylation of the -OH group (APZms) and addition of a strong base, tetramethylammonium phenolate (Me(4)N(+)C(6)H(5)O(-)), to completely deprotonate the APZs. Methylation led to recovery of reversible, bi-electronic behavior (Q/Q(*)(-) and Q(*)(-)/Q(2)(-)), indicating the nonacidic properties of the NH group. The addition of a strong base resulted in reduction of perezonate (Q(-)) obtained from the acid-base reaction of APZs with Me(4)N(+)C(6)H(5)O(-) to produce the dianion radical (Q(*)(2)(-)). Although the nitrogen atom interferes with direct conjugation between both rings by binding the quinone with the para-substituted ring, the UV-vis spectra of these compounds showed the existence of intramolecular electronic transfer from the respective aniline to the quinone moiety. (13)C NMR chemical shifts of the quinone atoms provided additional evidence for this electron transfer. These findings were also supported by linear variation in cathodic peak potentials (E(pc)) vs Hammett sigma(p) constants associated with the different electrochemical transformations: Q/Q(*)(-), Q(*)(-)/Q(2)(-) for APZms or HQ/HQH(2) and Q(-)/Q(*)(2)(-) for APZs. The electronic properties of model anilinebenzoquinones were determined at a B3LYP/6-31G(d,p) level of theory within the framework of the density functional theory. Our theoretical calculations predicted that all the compounds are floppy molecules with a low rotational C-N barrier, in which the degree of conjugation of the lone nitrogen pair with the quinone system depends on the magnitude of the electronic effect of the substituents of the aniline ring. Natural charges show that C(1) is more positive than C(4) although the LUMO orbital is located at C(4). Hence, if the natural charge distribution in the molecule controls the first electron addition, this should occur at carbon atom C(1). If the process is controlled by the LUMO orbitals, however, electron addition would first occur at C(4). For the APZms series susceptibility of the first reduction wave to the substitution effect (rho(pi) = 147 mV) is lower than that of the second reduction wave (rho(pi) = 156 mV). Thus, the first, one-electron transfer in the quinone system is controlled by the natural charge distribution of the molecule and therefore takes place at C(1).
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Benzoquinonas/síntese química , Acetonitrilas , Benzoquinonas/química , Cristalografia por Raios X , Eletroquímica , Indicadores e Reagentes , Modelos Moleculares , Espectrofotometria Ultravioleta , Relação Estrutura-AtividadeRESUMO
This study proposes the determination of the electronic delocalization contribution to the Anomeric Effect (EDCAE, Delta Delta E(deloc), eq 3) as a computational alternative in the evaluation of the excess of the axial preference shown by an electronegative substituent located at alpha position to the annular heteroatom of a heterocyclic compound (anomeric position) in both the presence and the absence of electronic delocalization retaining the same molecular geometry. The determination of the EDCAE is computationally accessible through the application of the natural bond orbital analysis (NBO). This type of analysis allows the comparison of hypothetical molecules lacking electronic delocalization (Lewis molecules, in which the electrons are strictly located in bonds and lone pairs) with the fully delocalized molecules retaining the same geometry and the evaluation of the anomeric effect in terms of eq 3. The role of the Lewis molecules is the same as the cyclohexane used experimentally to evaluate the anomeric effect. The advantage of doing this is that Lewis molecules are stereoelectronically inert. Applying this methology to cyclic and acyclic molecules at B3LYP/6-31G(d,p) and HF/6-31G(d,p)//B3LYP/6-31G(d,p) levels of theory, we found that the anomeric effect shown by Cl in 1,3-dioxane; F, Cl, SMe, PH(3), and CO(2)Me groups in 1,3-dithiane is of stereoelectronic nature while the preference of F, OMe, and NH(2) in 1,3-dioxane and the P(O)Me(2) group in 1,3-dithiane is not. Furthermore, this methodology shows that anomeric effects without stereoelectronic origin can modify the molecular geometry in agreement with the geometric pattern required by the double-bond no-bond model, as recently proposed by Perrin.
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Theoretical analysis within the frame of the Topological Theory of Atoms in Molecules confirms the repulsive steric interaction between an axial dimethylphosphinoyl group and the syn-diaxial hydrogens in cyclohexane derivative 2-ax. In seemingly good agreement with experiment, equatorial isomer 2-eq was calculated to be 1.49 kcal/mol more stable than 2-ax. (Experimental energy difference in (diphenylphosphinoyl)cyclohexane, Delta H(o) = 1.96 kcal/mol.) In contrast, axial 2-(dimethylphosphinoyl)-1,3,5-trithiane, 3-ax, was calculated to be 6.38 kcal/mol more stable than 3-eq. (Experimentally, the axial conformer of 2-(diphenylphosphinoyl)-1,3,5-trithiane, was found to be 1.43 kcal/mol more stable than the equatorial conformer, in solvent chloroform.) Theoretical analysis, in particular the electron density at the bond critical point within the C(4,6)-H...O=P bonding trajectory, implies significant bonding in this segment of interacting atoms. By the same token, substantial positive charge is acquired by the C--H bonds adjacent to the sulfonyl groups in disulfone 4. Hydrogen bonding between the phosphoryl group and H(4,6) leads to stabilization of 4-ax, which is estimated to be 5.0 kcal/mol lower in energy than 4-eq. This conclusion is supported by examination of P==O...H--C(4,6) bond trajectories, as well as from evaluation of the critical point properties along those interacting moieties. By contrast, fluorinated derivative 5 is more stable in the equatorial conformation, indicating a repulsive electrostatic interaction of the C--F...O-P entity in 5-ax.
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BACKGROUND: Among hypertensive patients, other risk factors for mortality and morbidity, besides blood pressure, must be considered when therapeutic decisions are done. AIM: To assess the incidence and relevance of cardiovascular risk factors in a cohort of patients with essential hypertension. MATERIAL AND METHODS: A cohort of 1,072 treated patients with essential hypertension was followed for a period up to 25 years. Four hundred eighty six were men and 586 were women, age ranged from 31 to 70 years. At entry, 56% of subjects did not have any organic complications associated to hypertension (stage I WHO criteria), 30% had mild alterations (Stage II) and 14% had major complications (myocardial infarction, stroke, heart failure or renal failure). Likewise, 43.8% had mild, 14.5%, moderate and 41.7%, severe hypertension. Patients were treated with monotherapy or combined therapy based on diuretics, beta blockers, calcium antagonists and angiotensin converting enzyme inhibitors. Goal of therapy was 140/90 mm Hg. Risk factors associated diseases and complications were registered carefully. Causes of death were obtained from hospital records and death certificates. Mortality was analyzed using life tables (intention to treat method included). RESULTS: Blood pressure dropped significantly during follow up from a mean of 182/110 to 154/92 mm Hg. During follow up, 143 patients died and 429 complications (lethal or non lethal) were recorded. Twenty four percent of patients smoked, 24% reported alcohol intake, 56% had hypercholesterolemia, 11% were obese, 13% had diabetes and 3% had gout. The proportional hazard model showed that the existence of previous complications, the presence of more than 3 risk factors, and age over 60 and mean systolic and diastolic pressure during therapy, were independent and significant risk factors for mortality. CONCLUSIONS: The incidence of risk factors among our hypertensive patients is very similar to that of other national or international cohorts.
Assuntos
Hipertensão/mortalidade , Adulto , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Chile/epidemiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de RiscoRESUMO
We synthesized and analyzed 19 compounds of 3'- (meta-) and 4'- (para-) substituted 2-[(R-phenyl)amine]-1,4-naphthalenediones (PANs) R = p-MeO, p-Me, p-Bu, p-Hex, p-Et, m-Me, m-Et, H, p-Cl, p-Br, m-F, m-Cl, p-COCH(3), m-CN, m-NO(2), m-COOH, and p-COOH. Despite the fact that the nitrogen atom, which binds the quinone with the meta- and para-substituted ring, interferes with the direct conjugation between both rings, the UV-vis spectra of these compounds show the existence of an intramolecular electronic transfer from the respective aniline to the p-naphthoquinone moiety. In accordance with this donor-acceptor character, the cyclic voltammograms of these compounds exhibit two, one-electron reduction waves corresponding to the formation of radical-anion and dianion, where the half-wave potential values vary linearly with the Hammett constants (sigma(x)). The analysis of the different voltammetric parameters (e.g., voltammetric function, anodic/cathodic peak currents ratio, and the separation between the anodic and cathodic potential peaks) show that with the exception of the carboxylic PAN derivatives, all compounds present the same reduction pathway. We investigated the molecular and electronic structures of these compounds using the semiempirical PM3 method and, within the framework of the Density Functional Theory, using the Becke 3LYP hybrid functional with a double zeta split valence basis set. Our theoretical calculations predict that, with the exception of the p-nitro compound, all the compounds are planar molecules where the conjugation degree of the nitrogen lone pair with the quinone system depends on the position and magnitude of the electronic effect of the substituent in the aniline ring. The Laplacians of the critical points (nabla(2)rho), for the C-O bonds, show that the first reduction wave corresponds to the carbonyl group in alpha-position to the aniline, and that the second one-electron transfer is due to the C(4)-O(2) carbonyl reduction. Thus, the higher reaction constant value (rho) obtained for the second one-electron transfer is due to the fact that the displacement of the nonshared electrons of the amino nitrogen merely modifies the electron density of C(4)-O(2) bond. The positive correlation between the LUMO energy values calculated for these compounds and the E(1/2) potentials corresponding to the C(1)-O(1) carbonyl reduction show that the electron addition takes place at the lowest unoccupied molecular orbital, supporting the fact that this wave is also prone to the substituent effect.