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The interaction between nitrogen-doped graphene defects (N3V1 and N4V2 pyridinic, and N3V1 and N3V3 pyrrolic) and benzene have been investigated by applying density functional theory (DFT), together with the vdW-DF correction. We discovered that only the N3V3 pyrrolic defect is a reactive site (6π-component), forming a cycloadduct with benzene (4π-component) that has energy barriers below 154.38 kJ mol-1 (1.60 eV). The conduction and valence bands (HOMO and LUMO) for N3V3 form a degenerate pair of orbitals at the gamma point, with the same ionization potential (IP) and electron affinity (EA). Likewise, inspection of the orbital symmetries for both systems confirms that these must undergo concerted reactions based on the Woodward and Hoffmann principles of orbital symmetry, with the appropriate orbital occupancies. This is the first time that substitutionally doped graphene has been demonstrated to participate as a 6π-component for cycloaddition reactions with benzene.
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INTRODUCTION: Primary lymphoma of the central nervous system is a variety of non-Hodgkin's lymphoma that accounts for 4-5% of intracranial tumours and 5% of all lymphomas. It has its origin in the brain, the eyes, the leptomeninges and the spinal cord with no systemic evidence of lymphomatoid activity; the subtype of lymphoma is predominantly of B-type cells. PATIENTS AND METHODS: We conducted a descriptive study of the patients diagnosed with primary brain lymphoma who were attended to at third-level centres in Mexico between the years 1980 and 2016. Patients who had been screened for systemic lymphoma were included. The results were analysed by means of simple frequencies, and disease-free and overall survival time was analysed by Kaplan-Meier curves; the differences among curves were analysed by means of log rank. RESULTS: Of a total of 215 patients, there were only 74 cases. By sex, 45% were females and 55% were males. Regarding age, 36.7% were over 60 years old. The most frequent clinical manifestations were motor loss (60%) and cognitive disorders (52%). Most patients received some form of chemotherapy (89%). The only significant factor for radiological response and clinical prognosis was the combined use of radiochemotherapy (p = 0.04493). CONCLUSION: Lymphoma is a tumorous condition with a high clinicoradiological response to treatment, although the response is not long-lasting. Its early identification and multidisciplinary management are essential for a more favourable prognosis in these patients.
TITLE: Linfoma primario del sistema nervioso central: experiencia clinica en un centro neurologico.Introduccion. El linfoma primario del sistema nervioso central es una variedad de linfoma no Hodgkin que representa el 4-5% de los tumores intracraneales y el 5% de todos los linfomas. Se origina en el encefalo, los ojos, la leptomeninge y la medula espinal sin evidencia sistemica de actividad linfomatoide; el subtipo de linfoma mayoritariamente es de celulas de tipo B. Pacientes y metodos. Estudio descriptivo de los pacientes diagnosticados con linfoma cerebral primario que fueron atendidos en centros de tercer nivel en Mexico entre los años 1980 y 2016. Se incluyo a los pacientes que contaran con cribado para busqueda de linfoma sistemico. Los resultados se analizaron mediante frecuencias simples; en el caso del tiempo libre de enfermedad y supervivencia global, mediante curvas de Kaplan-Meier, y las diferencias entre curvas, mediante log rank. Resultados. En un total de 215 pacientes solo hubo 74 casos. El 45% fueron mujeres y el 55%, hombres. El 36,7% eran mayores de 60 años. Las manifestaciones clinicas mas frecuentes fueron deficit motor (60%) y alteraciones cognitivas (52%). La mayoria recibio alguna forma de quimioterapia (89%). El unico factor significativo para respuesta radiologica y pronostico clinico era el uso combinado de radioquimioterapia (p = 0,04493). Conclusion. El linfoma representa una patologia tumoral con alta respuesta clinicorradiologica al tratamiento, aunque la respuesta no es duradera. Es fundamental su identificacion temprana y el tratamiento multidisciplinario para el mejor pronostico de estos pacientes.
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Neoplasias do Sistema Nervoso Central/epidemiologia , Linfoma não Hodgkin/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/complicações , Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Neoplasias do Sistema Nervoso Central/terapia , Quimiorradioterapia , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/etiologia , Irradiação Craniana , Doenças dos Nervos Cranianos/epidemiologia , Doenças dos Nervos Cranianos/etiologia , Epilepsias Parciais/epidemiologia , Epilepsias Parciais/etiologia , Humanos , Estimativa de Kaplan-Meier , Linfoma não Hodgkin/complicações , Linfoma não Hodgkin/terapia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Transtornos dos Movimentos/epidemiologia , Transtornos dos Movimentos/etiologia , Neuroimagem , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Centros de Atenção Terciária/estatística & dados numéricosRESUMO
INTRODUCTION: Radiotherapy with procarbazine, lomustine, and vincristine (PCV) improves overall survival in patients with anaplastic oligodendroglioma 1p19q codeleted. PATIENTS AND METHODS: This retrospective analysis investigated outcomes in patients with anaplastic oligodendroglioma 1p19q codeleted compared two different protocols (radiotherapy plus temozolomide or PCV). The primary end points were overall survival and progression-free survival. Secondary endpoint was the radiological response. RESULTS: A total of 48 patients were included. Mean age was 43 years (range: 19-66 years), 26 were male (54.1%). Twenty-one patients received PCV and 27 temozolomide. The baseline characteristics were not difference between the groups. The progression-free survival and overall survival in the PCV group were 7.2 and 10.6 years respectively and temozolomide were 6.1 and 9.2 years, both statistically significant. The radiological response was present in 80.9% in PCV arm and 70.2% in temozolomide arm there was not statistical differences. The multivariate Cox model showed only the significant parameters the use of PCV protocol. The toxicity grade 3 or 4 was present in 42.8% in PCV arm and 11.1% in temozolomide arm. CONCLUSIONS: The most common strategy in the Latin America community is the substitution of the PCV for temozolomide. This retrospective study showed superior efficacy of PCV than temozolomide. The Latin American community effort must be made to be able to have the drugs to available for using as a first line of treatment.
TITLE: Radioterapia mas temozolomida o PCV en pacientes con oligodendroglioma anaplasico con codelecion 1p19q.Introduccion. La radioterapia con procarbacina, lomustina y vincristina (PCV) mejora la supervivencia global en pacientes con oligodendroglioma anaplasico con codelecion 1p19q, pero no esta disponible en America Latina. Pacientes y metodos. Analisis retrospectivo comparando dos protocolos diferentes, radioterapia mas temozolomida o PCV, en pacientes con oligodendroglioma anaplasico con codelecion 1p19q. Los objetivos primarios fueron la supervivencia global y la supervivencia libre de progresion, y el objetivo secundario, la respuesta radiologica. Resultados. Se incluyo a 48 pacientes, 26 de ellos varones (54,1%), con una edad media de 43 años (rango: 19-66 años). Veintiun pacientes recibieron PCV, y 27, temozolomida. Las caracteristicas iniciales no tuvieron diferencias entre los grupos. La supervivencia libre de progresion y la supervivencia global en el grupo con PCV fueron de 7,2 y 10,6 años, y en el grupo de temozolomida, de 6,1 y 9,2 años, respectivamente, unos resultados estadisticamente significativos. Hubo respuesta radiologica en el 80,9% en el brazo de PCV y el 70,2% en el brazo de temozolomida. El analisis multivariado de Cox mostro como unico parametro significativo el uso del protocolo PCV. El grado de toxicidad 3-4 estuvo presente en el 42,8% en el brazo de PCV y en el 11,1% en el brazo de temozolomida. Conclusiones. La estrategia mas comun en America Latina es la sustitucion de PCV por temozolomida. Este estudio retrospectivo mostro una eficacia superior de PCV que de la temozolomida. La diferencia obliga a la comunidad latinoamericana a hacer un esfuerzo colectivo para poder tener acceso a los medicamentos para su uso como primera linea de tratamiento.
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Antineoplásicos Alquilantes/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Oligodendroglioma/tratamento farmacológico , Oligodendroglioma/radioterapia , Temozolomida/uso terapêutico , Adulto , Idoso , Neoplasias Encefálicas/genética , Terapia Combinada , Feminino , Deleção de Genes , Humanos , Lomustina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligodendroglioma/genética , Procarbazina/uso terapêutico , Estudos Retrospectivos , Vincristina/uso terapêutico , Adulto JovemRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha neopauciflora Pax is an endemic species to Mexico, and its latex is used in traditional medicine to treat mouth infections when there are loose teeth and to heal wounds. In this research, we evaluated the antimicrobial activity, wound healing efficacy and chemical characterization of J. neopauciflora latex in a murine model. MATERIALS AND METHODS: The antibacterial activity was determined using Gram positive and negative strains, the antifungal activity was determined using yeast and filamentous fungi, and the wound healing efficacy of the latex was determined using the tensiometric method. The anti-inflammatory activity was evaluated using the plantar oedema model in rats, administering the latex orally and topically. Cytotoxic activity was determined in vitro in two different cell lines. Antioxidant capacity, total phenolics, total flavonoids, reducing carbohydrates and latex proteins were quantified. The latex analysis was performed by High Performance Liquid Chromatography (HPLC). Finally, molecular exclusion chromatography was performed. RESULTS: The latex demonstrated antibacterial activity. The most sensitive strains were Gram positive bacteria, particularly S. aureus (MIC=2mg/mL), and the latex had bacteriostatic activity. The latex did not show antifungal activity. The latex demonstrated a wound-healing efficacy, even the positive control (Recoveron). The orally administered latex demonstrated the best anti-inflammatory activity and was not toxic to either of the 2 cell lines. The latex had a high antioxidant capacity (SA50=5.4µg/mL), directly related to the total phenolic (6.9mg GAE/mL) and flavonoid (12.53µg QE/mL) concentration. The carbohydrate concentration was 18.52µg/mL, and fructose was the most abundantly expressed carbohydrate in the latex (14.63µg/mL, 79.03%). Additionally, the latex contained proteins (7.62µg/mL) in its chemical constitution. As secondary metabolites, the HPLC analysis indicated the presence of phenols and flavonoids. CONCLUSIONS: The J. neopauciflora latex promotes the wound healing process by avoiding microorganism infections, inhibiting inflammation and acting as an antioxidant.
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Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Jatropha , Látex/farmacologia , Células 3T3-L1 , Animais , Anti-Infecciosos/química , Anti-Inflamatórios/química , Linhagem Celular Tumoral , Flavonoides/análise , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Látex/química , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Fenóis/análise , Proteínas de Plantas/análise , Ratos Wistar , Cicatrização/efeitos dos fármacosRESUMO
BACKGROUND: Ethnopharmacological relevance. Jatropha neopauciflora (Pax) is an endemic species of the Tehuacan- Cuicatlan Valley, Mexico. This species has long been used as a remedy to alleviate illnesses of bacterial, fungal and viral origin. Aim of the study. Experimentally test the traditional use of Jatropha neopauciflora in Mexican traditional medicine. MATERIALS AND METHODS: The methanol extract (MeOH1), of Jatropha neopauciflora (Euphorbiaceae) was obtained by maceration. Next, the methanol (MeOH2) and hexane (H) fractions were obtained. The essential oil was obtained by hydro- distillation. The extract, fractions and essential oil were analyzed by GC-MS. The antimicrobial activity was measured by the disc diffusion agar and radial inhibition growth methods. RESULTS: The extract and fractions showed antibacterial activity against eleven strains (five Gram-positive and six Gram- negative) and a bacteriostatic effect in the survival curves for Staphylococcus aureus and Vibrio cholerae. The extract and fractions were also shown to have antifungal activity, particularly against Trichophyton mentagrophytes (CF50 = MeOH1: 1.07 mg/mL, MeOH2: 1.32 mg/mL and H: 1.08 mg/mL). The antioxidant activity of MeOH1 (68.6 µg/mL) was higher than for MeOH2 (108.1 µg/mL). The main compounds of the essential oil were ß-pinene, 1,3,8-p-menthatriene, ledene, m- menthane, linalyl acetate and 3-carene. The main compounds of MeOH1 were ß-sitosterol, lupeol and pyrogallol; the main compounds of MeOH2 were ß-sitosterol, spathulenol, coniferyl alcohol and lupeol; and the main compounds of H were ß-sitostenone, γ-sitosterol and stigmasterol. CONCLUSIONS: This study indicates that Jatropha neopauciflora is a potential antibacterial and antifungal agent.
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Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Jatropha/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Anti-Infecciosos/isolamento & purificação , México , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Trichophyton/efeitos dos fármacos , Trichophyton/fisiologiaRESUMO
The hydrogen spill-over mechanism was studied by applying Density Functional Theory. We used small palladium clusters to act as the catalyst supported on the substrate (comprised of pyridinic and pyrrolic nitrogen doped graphene), in order to study hydrogen dissociation, migration and diffusion. Charge transfer and strong binding between the catalyst and the substrate lead to dissociated states of H2 and prevent clusters from detaching and coalescing. In dissociated cases of H2 on Pd clusters, energy barriers below 0.6 eV were found. Likewise, concerning hydrogen migration from the catalyst to the substrate, energy barrier values of 0.8 eV (pyridinic defect) and 0.5 eV (pyrrolic defect) were apparent in the case of the Pd4 cluster at full hydrogen saturation. This indicates that hydrogen dissociation and migration may occur spontaneously at room temperature. This result shows that the interaction between the defects and the small metal clusters may explain the role that defects play in hydrogen migration from the catalyst to the substrate. Subsequently, it was found that thermal desorption does not limit chemisorbed hydrogen diffusion on the substrate. This work may thus help to determine experimental strategies with the capacity to enhance hydrogen storage.
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OBJECTIVE: To describe the experience with upper gastrointestinal bleeding in two major Latin American hospitals; presenting its main causes, treatment, and prognosis, while exploring some risk factors associated with death. DESIGN: Prospective cohort study. PATIENTS AND METHODS: Four hundred and sixty four patients were admitted into any of the 2 hospitals and were at least 15 years of age. Some variables demographics, clinics and treatment were studied. The association between those variables and the death were explored. RESULTS: Mean age was 57.9 years; the men:women ratio was 1.4:1. Three hundred and fifty nine patients (77.3%) presented as outpatients and 105 patients (22.6%) were inpatients presenting with UGIB. 71.6% of patients had an upper GI endoscopy within 24 hours. The main causes of bleeding were peptic ulcer (190 patients, 41%), erosive disease (162 patients, 34.9%) and variceal bleeding (47 patients, 10.1%). Forty four patients died (9.5%). Bleeding as an inpatient has a higher mortality risk than does bleeding as an outpatient (RR 2.4 IC 95% 1.2-4.6). An increasing number of comorbidities such as those described in the Rockall Score are also associated with a higher risk of dying (RR 2.5 IC 95% 1.1-5.4). CONCLUSION: UGIB as an inpatient and the presence of comorbidities should alert the clinician in identifying patients at higher risk of a fatal outcome, these patients should have a more aggressive management and be entitled to an early intervention.
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Varizes Esofágicas e Gástricas/mortalidade , Hemorragia Gastrointestinal/mortalidade , Adulto , Idoso , Anticoagulantes/efeitos adversos , Colômbia/epidemiologia , Comorbidade , Úlcera Duodenal/mortalidade , Embolização Terapêutica , Endoscopia do Sistema Digestório , Esofagite/complicações , Esofagite/mortalidade , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Hospitais Gerais/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Hospitais Urbanos/estatística & dados numéricos , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/estatística & dados numéricos , Úlcera Péptica Hemorrágica/mortalidade , Estudos Prospectivos , Fatores de Risco , Neoplasias Gástricas/complicações , Neoplasias Gástricas/mortalidade , Úlcera Gástrica/mortalidadeRESUMO
The case of an intracranial tumor with intraventricular localization, in an usually healthy patient is presented. The main clinical symptom was the sudden onset of a strong intensity cephalea, which was persistent and unusual. The neurological examination did not show any abnormalities. Clinical aspects corresponding to this case are revised and compared with those reported in the literature.
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Cistos do Sistema Nervoso Central/complicações , Cefaleia/etiologia , Terceiro Ventrículo , Adulto , Feminino , HumanosRESUMO
Oncogenes bcl1 and bcl2 are located in the rupture site of t(11;14) and t(14; 18), respectively. They have been found to rearrange in different B-cell malignancies. A molecular study of oncogenes bcl1 and bcl2 was carried out in 42 patients diagnosed of B-cell chronic lymphoid leukaemia. In 14.3% of the patients the rearrangement affected bcl1, but no differences were found with regard to stage and clinical course between these patients and those without any oncogen rearrangement. In all the patients studied bc12 was in a germinal configuration.