Kalanchoe pinnata (Lam.) Pers. Leaf ethanolic extract exerts selective anticancer activity through ROS-induced apoptotic cell death in human cancer cell lines.

BACKGROUND: The leaves of Kalanchoe pinnata (Lam.) Pers. (K. pinnata), a succulent plant native to tropical regions, are used as a medicinal alternative against cancer in several countries worldwide; however, its therapeutic potential to fight cancer has been little addressed. In this study, we analyzed the phytochemical content, antioxidant capacity, and selectivity of K. pinnata leaf ethanolic extract against different human cancer cell lines in vitro. METHODOLOGY: This study subjected the ethanolic extract to enzymatic assays to quantify the phytochemical content (phenolics, flavonoids, and anthraquinones) and its radical scavenging and iron-reducing capacities. Also, the phytoconstituents and major phenolic compounds present in the extract's subfractions were identified by GC-MS, HPLC, and NMR. Human cancer (MCF-7, PC-3, HT-29) and normal colon (CoN) cell lines were treated with different concentrations of K. pinnata leaf ethanolic extract, and the changes in cell proliferation (sulforhodamine B assay), caspases activity (FITC-VAD-FMK reporter), mitochondrial membrane potential (MMP, rhodamine 123 assay), chromatin condensation/fragmentation (Hoechst 33342 stain), and ROS generation (DCFH2 probe assay) were assessed. RESULTS: The results showed that the K. pinnata leaf ethanolic extract is rich in phytoconstituents with therapeutic potential, including phenols (quercetin and kaempferol), flavonoids, fatty acid esters (34.6% of the total composition), 1- triacontanol and sterols (ergosterol and stigmasterol, 15.4% of the total composition); however, it presents a poor content of antioxidant molecules (IC50 = 27.6 mg/mL for H2O2 scavenging activity vs. 2.86 mg/mL in the case of Trolox). Notably, the extract inhibited cell proliferation and reduced MMP in all human cell lines tested but showed selectivity for HT-29 colon cancer cells compared to CoN normal cells (SI = 8.4). Furthermore, ROS generation, caspase activity, and chromatin condensation/fragmentation were augmented significantly in cancer-derived cell lines, indicating a selective cytotoxic effect. CONCLUSION: These findings reveal that the K. pinnata leaf ethanolic extract contains several bioactive molecules with therapeutic potential, capable of displaying selective cytotoxicity in different human cancer cell lines.

Pensamiento suicida en médicos residentes con la escala de Plutchik en dos instituciones de salud en Ciudad Obregón, Sonora, México

Objetivo: Evaluar la incidencia y factores asociados al pensamiento suicida en una muestra de médicos residentes de dos instituciones. Materiales y métodos: Se realizó un estudio de tipo descriptivo, observacional, prospectivo y transversal, entre los meses de septiembre a octubre del 2022, para estimar el pensamiento suicida en los médicos residentes de dos hospitales con la escala de Plutchik, además de buscar factores asociados. Se aplicó la estadística descriptiva con medidas de tendencia central y de dispersión, frecuencias relativas y absolutas; las pruebas ji al cuadrado de Pearson y de bondad de ajuste, así como la prueba de Kruskal-Wallis se emplearon para examinar las diferencias entre especialidades, y la prueba post-hoc de Tukey para evaluar la especialidad diferente. Resultados: Se respondió un total de 225 encuestas, de las cuales se eliminaron 20 por inadecuado diligenciamiento, y quedaron 205. El promedio de edad fue de 28,66 años (DS ± 2,360) y el 71,2 % correspondió al sexo femenino. En cuanto a las especialidades, se encontró a pediatría con el 28,8 % y a anestesiología con el 20,5 %. Se evidenció asociación significativa entre especialidades, con un valor de p = 0,0000, y grado académico de p = 0,003 (p ≤ 0,05). Según la especialidad, se encontraron diferencias en cuanto al pensamiento suicida; la prueba de Kruskal-Wallis mostró un valor de p = 0,000 y la prueba post-hoc de Tukey reveló que la especialidad de ginecología fue la diferente. Conclusiones: De acuerdo con los resultados de la muestra, alrededor de una cuarta parte de los médicos residentes manifiesta pensamiento suicida. La prevalencia en dicha muestra no presenta diferencia significativa con respecto a la incidencia a nivel latinoamericano. Se encontró una asociación entre ideas suicidas, especialidades médicas y grado académico. En cuanto a comparación entre las especialidades, ginecología fue la que mostró mayor ideación suicida. Este trabajo presenta algunas limitaciones, por ejemplo, existe una gran heterogeneidad de grupos, no se empleó una técnica de selección probabilística y las pruebas estadísticas empleadas fueron no paramétricas.

Objective: To evaluate the incidence and factors associated with suicidal ideation in a sample of resident physicians from two institutions. Materials and methods: A descriptive, observational, prospective and cross-sectional study was carried out to estimate the suicidal ideation and associated factors with the Plutchik Suicide Risk Scale among resident physicians from two hospitals between September and October 2022. Descriptive statistics were used with measures of central tendency and dispersion, as well as relative and absolute frequencies. In addition, Pearson's chi-square goodness of fit test and Kruskal-Wallis H test were used to examine the differences between specialties, and Tukey's Honest Significant Difference test to determine which specialty was different. Results: A total of 225 surveys were answered, out of which 20 were eliminated due to inadequate completion, leaving 205 complete surveys for analysis. The average age was 28.66 years (SD ± 2.360) and 71.2 % were females. Concerning the specialties, pediatrics was found in 28.8 % of the respondents and anesthesiology in 20.5 %. A significant association between specialties with a value of p = 0.0000 and academic degrees with p = 0.003 (p ≤ 0.05) was evidenced. Differences regarding suicidal ideation were found by specialty: Kruskal-Wallis H test showed a value of p = 0.000 and Tukey's Honest Significant Difference test revealed that the specialty of gynecology was the different one. Conclusions: According to the results of the study sample, approximately one fourth of the resident physicians had suicidal ideation. Its prevalence in this sample showed no significant difference with respect to its incidence in Latin America. An association between suicidal ideation, medical specialties and academic degree was found. As for the comparison between specialties, gynecology was the one with the highest suicidal ideation rate. This work had some limitations; for example, the groups were very heterogeneous, a probabilistic selection technique was not used, and the statistical tests were nonparametric.

Prevalence and clinical characteristics of depression and symptoms of anxiety in staff at a health institution in Medellin during the COVID-19 pandemic.

INTRODUCTION: The COVID-19 pandemic has represented an extraordinary challenge for health workers as they care for others while exposing themselves to contagion. Doctors, nurses, therapists and other non-care staff in clinics and hospitals are asked to be prepared to work in particularly complex and stressful situations, which makes them vulnerable to mental health problems. OBJECTIVE: To determine the prevalence and clinical characteristics of anxiety and depression symptoms in staff working at a health institution in Medellin, Colombia. METHODS: Observational, descriptive and cross-sectional study, based on a survey designed for the investigation, which included two scales to screen depression and anxiety symptoms, as well as sociodemographic variables. RESULTS: A total of 1,247 workers from the health institution were included. Of these, 14.6% reported symptoms of depression and 18.5% of clinically significant anxiety. A higher proportion of moderate to severe depression and anxiety symptoms was found in those working face to face. CONCLUSIONS: Anxiety and depression symptoms are highly prevalent among staff at a health institution in Medellin, Colombia, during the COVID-19 pandemic. Given the vital role of the health sector in times of pandemic, the development of mental health programmes that address the problems of this population should be considered a priority.

Prevalencia y características clínicas de los síntomas depresivos y ansiosos de los trabajadores de una institución de salud en Medellín durante la pandemia por COVID-19

Introducción: Afrontar las circunstancias de la vida y el trabajo que la pandemia por COVID-19 ha impuesto al personal sanitario implica un reto extraordinario: cuidar y atender a otros, exponiéndose a sí mismos al contagio. A médicos, enfermeras, terapeutas y demás personal asistencial y no asistencial en clínicas y hospitales, se les pide estar preparados para trabajar en situaciones extraordinariamente complejas y estresantes, lo que los hace vulnerables a problemas mentales. Objetivo: Determinar la prevalencia y las características clínicas de los síntomas ansiosos y depresivos del personal que trabaja en una institución de salud en Medellín, Colombia. Métodos: Estudio observacional, descriptivo y transversal, a partir de una encuesta disenada al efecto, la cual incluyó 2 escalas para tamizar síntomas depresivos y ansiosos, además de variables sociodemográficas. Resultados: Se incluyó a 1.247 trabajadores de la institución de salud. El 14,6% reportó síntomas depresivos y el 18,5%, ansiosos clínicamente significativos. Se encontró una mayor proporción de síntomas depresivos y ansiosos moderados-graves en la modalidad de trabajo presencial. Conclusiones: Los síntomas ansiosos y depresivos son muy prevalentes entre los trabajadores de una institución de salud de Medellín durante la pandemia de COVID-19. Dado el papel vital del sector salud en tiempos de pandemia, el desarrollo de programas de salud mental que aborden los problemas de esta población debería considerarse una prioridad.

Introduction: The COVID-19 pandemic has represented an extraordinary challenge for health workers as they care for others while exposing themselves to contagion. Doctors, nurses, therapists and other non-care staff in clinics and hospitals are asked to be prepared to work in particularly complex and stressful situations, which makes them vulnerable to mental health problems. Objective: To determine the prevalence and clinical characteristics of anxiety and depression symptoms in staff working at a health institution in Medellin, Colombia. Methods: Observational, descriptive and cross-sectional study, based on a survey designed for the investigation, which included two scales to screen depression and anxiety symptoms, as well as sociodemographic variables. Results: A total of 1,247 workers from the health institution were included. Of these, 14.6% reported symptoms of depression and 18.5% of clinically significant anxiety. A higher proportion of moderate to severe depression and anxiety symptoms was found in those working face to face. Conclusions: Anxiety and depression symptoms are highly prevalent among staff at a health institution in Medellin, Colombia, during the COVID-19 pandemic. Given the vital role of the health sector in times of pandemic, the development of mental health programmes that address the problems of this population should be considered a priority.

Prevalence and Clinical Characteristics of Depression and Anxiety Symptoms in Staff at a Health Institution in Medellin During the COVID-19 Pandemic. / Prevalencia y características clínicas de los síntomas depresivos y ansiosos de los trabajadores de una institución de salud en Medellín durante la pandemia por COVID-19.

INTRODUCTION: The COVID-19 pandemic has represented an extraordinary challenge for health workers as they care for others while exposing themselves to contagion. Doctors, nurses, therapists and other non-care staff in clinics and hospitals are asked to be prepared to work in particularly complex and stressful situations, which makes them vulnerable to mental health problems. OBJECTIVE: To determine the prevalence and clinical characteristics of anxiety and depression symptoms in staff working at a health institution in Medellin, Colombia. METHODS: Observational, descriptive and cross-sectional study, based on a survey designed for the investigation, which included two scales to screen depression and anxiety symptoms, as well as sociodemographic variables. RESULTS: A total of 1,247 workers from the health institution were included. Of these, 14.6% reported symptoms of depression and 18.5% of clinically significant anxiety. A higher proportion of moderate to severe depression and anxiety symptoms was found in those working face to face. CONCLUSIONS: Anxiety and depression symptoms are highly prevalent among staff at a health institution in Medellin, Colombia, during the COVID-19 pandemic. Given the vital role of the health sector in times of pandemic, the development of mental health programmes that address the problems of this population should be considered a priority.

Subtipos neurocognitivos de esquizofrenia / Neurocognitive Subtypes of Schizophrenia

Objetivo. Identificar empíricamente subtipos neurocognitivos de esquizofrenia y establecer la asociación de estos con características clínicas. Métodos. Se aplicaron pruebas de atención sostenida, función ejecutiva, reconocimiento facial de emociones, memoria verbal y de trabajo a 253 sujetos con esquizofrenia. A partir de los resultados de estas pruebas se identificaron los subtipos mediante análisis de clases latentes. Posteriormente, se evaluó la asociación de cada subtipo con características clínicas. Resultados. Se identificaron cuatro subtipos: 1) déficit cognitivo global, 2) déficit de memoria y función ejecutiva, 3) déficit de memoria y reconocimiento de emociones y 4) sin déficit cognitivo. Al comparar con el subtipo sin déficit cognitivo, se observó que tanto el de déficit de memoria y función ejecutiva como el de déficit cognitivo global tenían mayor frecuencia individuos de sexo masculino, desempleados, con deterioro grave y adherentes al tratamiento. Sin embargo, en el subtipo con déficit cognitivo global la diferencia fue más alta y presentaron una frecuencia más baja de antecedentes de episodios depresivos (OR 0,39; IC95%: 0,16 a 0,97). El subtipo de déficit de memoria y reconocimiento emocional tenía más sujetos con deterioro grave (OR 5,52; IC95%: 1,89 a 16,14) y desempleo (OR 2,43; IC95%: 1,06 a 5,55), pero menos con antecedentes de episodios depresivos (OR 0,21; IC95%: 0,07 a 0,66). Conclusión. Los resultados muestran cuatro subtipos neurocognitivos de esquizofrenia con un posible espectro de severidad, asociándose en un extremo con mayor disfunción, y en el otro con mayor psicopatología afectiva y menor adherencia al tratamiento

Objective. To empirically identify schizophrenia neurocognitive subtypes and establish their association with clinical characteristics. Methods. Sustained attention, executive function, facial emotion recognition, verbal learning, and working memory tests were applied to 253 subjects with schizophrenia. We identified neurocognitive subtypes by a latent class analysis of the tests results. After, we made a search for the association of these subtypes with clinic characteristics. Results. We identified four neurocognitive subtypes: 1) 'Global cognitive deficit', 2) 'Memory and executive function deficit', 3) 'Memory and facial emotion recognition deficit,' and 4) 'Without cognitive deficit.' In comparison with the subtype 'without cognitive deficit,' we found that the 'memory and executive function deficit subtype' and the 'global cognitive deficit subtype' had a higher frequency of male, unemployed, severe impairment, and adherence to treatment participants. However, in the 'global cognitive deficit subtype' the differences were higher and there was also a lower frequency of past major depressive episodes (OR 0.39; 95%CI: 0.16 to 0.97). The 'memory and facial recognition deficit subtype' had a higher probability of severe impairment (OR 5.52; 95%CI: 1.89 to 16.14) and unemployed (OR 2.43; 95%CI: 1.06 to 5.55) participants, but also a lower probability of past depressive episodes (OR 0.21; 95%CI: 0.07 to 0.66). Conclusion. Our results suggest the existence of four neurocognitive subtypes in schizophrenia with a spectrum of dysfunction and severity. We found higher dysfunction in those with worse cognitive dysfunction, and higher affective psychopathology and less treatment adherence in those with less cognitive dysfunction

Neurocognitive subtypes of schizophrenia.

OBJECTIVE: To empirically identify schizophrenia neurocognitive subtypes and establish their association with clinical characteristics. METHODS: Sustained attention, executive function, facial emotion recognition, verbal learning, and working memory tests were applied to 253 subjects with schizophrenia. We identified neurocognitive subtypes by a latent class analysis of the tests results. After, we made a search for the association of these subtypes with clinic characteristics. RESULTS: We identified four neurocognitive subtypes: 1) “Global cognitive deficit”, 2) “Memory and executive function deficit”, 3) “Memory and facial emotion recognition deficit,” and 4) “Without cognitive deficit.” In comparison with the subtype “without cognitive deficit,” we found that the “memory and executive function deficit subtype” and the “global cognitive deficit subtype” had a higher frequency of male, unemployed, severe impairment, and adherence to treatment participants. However, in the “global cognitive deficit subtype” the differences were higher and there was also a lower frequency of past major depressive episodes (OR 0.39; 95%CI: 0.16 to 0.97). The “memory and facial recognition deficit subtype” had a higher probability of severe impairment (OR 5.52; 95%CI: 1.89 to 16.14) and unemployed (OR 2.43; 95%CI: 1.06 to 5.55) participants, but also a lower probability of past depressive episodes (OR 0.21; 95%CI: 0.07 to 0.66). CONCLUSION: Our results suggest the existence of four neurocognitive subtypes in schizophrenia with a spectrum of dysfunction and severity. We found higher dysfunction in those with worse cognitive dysfunction, and higher affective psychopathology and less treatment adherence in those with less cognitive dysfunction.

Como pide nuestro cuerpo la ortodoncia / How our body asks for orthodontics

Resumen En el momento de realizar un tratamiento de ortodoncia, generalmente se evalúan condiciones dentales en cuanto a estética y función sin ir más allá de estos dos parámetros. Al existir una interconexión entre los diferentes sistemas del cuerpo humano, una relación dental y/o esquelética alterada puede generar desordenes que se manifiestan en otros órganos distantes de la cavidad oral. Se puede tener una relación entre determinadas maloclusiones con: alteraciones psicosociales, bulling, alteraciones cardiacas, dolores de cabeza, alteraciones oculares y auditivas, de las cuerdas vocales, del sistema gastrointestinal y respiratorio, en la postura, además de alteraciones en el sistema estomatognático. El propósito de este artículo es identificar como algunas maloclusiones y mal posiciones dentales repercuten en diferentes partes del cuerpo, ocasionando signos y síntomas que alteran la vida cotidiana de un individuo, sin saber que el factor etiológico se encuentra en su boca.

At the time of orthodontic treatment, dental conditions are evaluated in terms of aesthetics and function but not beyond these two parameters. Since there is an interconnection between different systems of the body, an altered dental and skeletal relationship could generate disorders that could manifest in distant organs from the oral cavity. Malocclusion of teeth can be related to psychosocial alterations, bullying, cardiac problems, headaches, ocular and hearing disorders, vocal cords, gastrointestinal system, infections caused by Helicobacter Pylori, breathing, posture and anomalies of the stomatognathic system. The purpose of this article is to identify how some malocclusions and dental anomalies affect different parts of the body, causing symptoms and clinical signs that compromise the health of patients where the main etiological factor is in the mouth.

Verbal working memory in individuals with schizophrenia and their first degree relatives: relationship with negative and disorganized symptoms.

OBJECTIVE: To determine whether there are differences in verbal working memory amongst subjects with schizophrenia, their first degree relatives and controls, and to evaluate the influence of symptoms on these differences, as an initial step to assess whether this cognitive function is an endophenotype. METHODS: We examined 197 cases with schizophrenia, 197 first degree relatives and 200 controls through psychiatric interviews and the Letters and Numbers Sequencing test (LNS). Performance was compared among the three groups adjusting for age, sex and education level. Adjustment for "negative symptoms" and "disorganization" was performed afterwards. RESULTS: Subjects with schizophrenia showed lower performance in the LNS than their first degree relatives and the healthy controls; the effect sizes were 0.75 and 1.18 respectively. There was a small difference between relatives and controls (effect size =0.38). These differences were significant after adjustment for negative and disorganized symptoms, but the effect sizes became smaller: 0.26 for relatives vs. subjects with schizophrenia, 0.56 for controls vs. subjects with schizophrenia and 0.33 for relatives vs. controls. Among individuals with schizophrenia, performance in the LNS was not associated with disorder duration, disease onset age, antipsychotics, history of depressive episodes or substance use disorders. CONCLUSION: Results suggest verbal working memory may be considered as an endophenotype in schizophrenia.

Memoria de trabajo verbal en individuos con esquizofrenia y sus familiares de primer grado: Relación con los sintomas negativos y desorganizados / Verbal working memory in individuals with schizophrenia and their first degree relatives: relationship with negative and disorganized symptoms

Objetivo: Determinar si hay diferencias en la memoria de trabajo verbal entre sujetos con esquizofrenia, familiares de primer grado y controles, y evaluar la influencia que pueden tener en estas diferencias los síntomas del trastorno, como un paso para establecer si esta función cognitiva es un endofenotipo. Métodos: A 197 sujetos con esquizofrenia, 197 familiares de primer grado y 200 controles comunitarios, se les hizo evaluación psiquiátrica y se les aplicó la prueba sucesión de letras y números (SLN). Se comparó el desempeño de los tres grupos ajustando por edad, sexo y escolaridad, y luego se ajustó también por síntomas negativos y desorganizados. Resultados: Los sujetos con esquizofrenia mostraron un menor desempeño en la SLN con respecto a sus familiares de primer grado no-afectados y los controles, con tamaños de efecto de 0,75 y 1,18 respectivamente. Hubo una diferencia pequeña pero significativa entre familiares y controles (tamaño de efecto =0,38). Estas diferencias siguieron siendo significativas después de ajustar por síntomas negativos y desorganizados, pero los tamaños de efecto disminuyeron a: 0,26 para familiares vs sujetos con esquizofrenia, 0,56para controles vs sujetos con esquizofrenia y 0,33 para familiares vs controles. Entre los sujetos con esquizofrenia, el desempeño en la SLN no se asoció significativamente con duración del trastorno, edad de inicio, uso de antipsicóticos, ni historia de episodios depresivos o trastornos por uso de sustancias. Conclusión: Los resultados sugieren que la memoria de trabajo verbal puede ser considerada un endofenotipo de la esquizofrenia (AU)

Objective: To determine whether there are differences in verbal working memory amongst subjects with schizophrenia, their first degree relatives and controls, and to evaluate the influence of symptoms on these differences, as an initial step to assess whether this cognitive function is an endophenotype. Methods: We examined 197 cases with schizophrenia, 197 first degree relatives and 200 controls through psychiatric interviews and the Letters and Numbers Sequencing test (LNS). Performance was compared among the three groups adjusting for age, sex and education level. Adjustment for “negative symptoms” and “disorganization” was performed afterwards. Results: Subjects with schizophrenia showed lower performance in the LNS than their first degree relatives and the healthy controls; the effect sizes were 0.75 and 1.18 respectively. There was a small difference between relatives and controls (effect size =0.38). These differences were significant after adjustment for negative and disorganized symptoms, but the effect sizes became smaller: 0.26 for relatives vs. subjects with schizophrenia, 0.56 for controls vs. subjects with schizophrenia and 0.33 for relatives vs. controls. Among individuals with schizophrenia, performance in the LNS was not associated with disorder duration, disease onset age, antipsychotics, history of depressive episodes or substance use disorders. Conclusion: Results suggest verbal working memory may be considered as an endophenotype in schizophrenia (AU)

Diagnostic test validation: cochlear hydrops analysis masking procedure in Ménière's disease.

OBJECTIVE: To determine the diagnostic value of the cochlear hydrops analysis masking procedure (CHAMP) in patients with definite Ménière's disease. STUDY DESIGN: Prospective validation study for a diagnostic test, study phase 2. SETTING: Tertiary referral centers. PATIENTS: Subjects with definite Ménière's disease (Group 1), differential diagnosis (Group 2: another audiovestibular diseases or neurologic disorders), and normal hearing (Group 3) were included. Sample sizes were calculated. INTERVENTIONS: Study test (CHAMP) was compared with the current clinical criterion standard described by the guidelines of the American Academy of Otolaryngology-Head and Neck Surgery. MAIN OUTCOME MEASURE: Sensitivity, specificity, and other indicators of diagnostic validation. RESULTS: One hundred ten cases completed the follow-up, and their results are presented. Sensitivity at 31.3% and specificity at 100% were found in subjects with definite Ménière's disease, features that are more helpful in confirming the diagnosis than in rejecting it. Group 1 showed significantly shorter latency delays than Groups 2 and 3 (p < 0.001). CONCLUSION: If definite Ménière's disease is suspected, an abnormal result confirms the diagnosis; however, a normal result does not rule out the Ménière's disease diagnosis.

Red cell membrane lipid changes at 3,500 m and on return to sea level.

Previous studies have shown that acute hypobaric hypoxia, obtained in a hypobaric chamber, and subsequent reoxygenation, give rise to modifications of the erythrocyte membrane lipid dynamics, resulting in an increased lateral diffusivity of the membrane lipids, and this was interpreted as the result of a modified lipid-protein interaction. The aim of the present study was to determine the effect of the reoxygenation condition in individuals after 3 days at an altitude of 3,500 m above sea level. Reoxygenation was a consequence of returning to sea level. Resting blood samples from both conditions were obtained, and erythrocytes were separated and immediately lysed for membrane isolation. We measured the bilayer polarity in membranes with Laurdan, a fluorescent probe. We also measured malondialdehyde in membrane lipids, an indicator of oxidative damage. We found a 12% (p = 0.016, n = 7) increase in the polarity of the membrane bilayer surface, and an increase of 70% (p = 0.005, n = 7) in the formation of malondialdehyde in the membrane after the reoxygenation condition. The membrane bilayer polarity increase is due to an oxidative modification of the phospholipid backbone after reoxygenation. People working and/or recreating at moderate altitude (3,500 m) may be at risk of erythrocyte membrane oxidative damage upon returning to sea level, and therefore a better understanding of the processes occurring upon reoxygenation may lead to proposed strategies to minimize this effect.

Electron-donating properties of p-phenylene phosphine imides: an electrochemical and spectroscopic investigation.

[reaction: see text] Electronic properties of phosphine imide based organic electron donors have been investigated. N,N'-p-Phenylenebis(triphenyl)phosphine imide (Ph(3)P=NC(6)H(4)N=PPh(3), 1) has two reversible single-electron oxidations (0.04 and 0.53 V vs SCE). Spectroscopic investigations of poly(p-phenylene phosphine imide)s (2) are similar to those of polymer model compounds, suggesting formation of localized radical cations on the polymer chains and electronically insulating phosphorus atoms.

Influencia de la ingesta de aceites vegetales en la absorción intestinal de glucosa in vitro en hamster dorado / Influence of intake of vegetables oils on the in vitro intestinal absorptions of glucose in golden hamster

Para esclarecer la influencia de la ingesta de aceites vegetales con diferente grado de insaturación sobre la absorción intestinal de glucosa, se alimentaron durante cuatro semanas Hamster machos (Mesocricetus aureatus) con dietas estandarizadas al 15 por ciento de aceite de Rosa mosqueta, Maravilla, Oliva o Coco. Al cabo del período de ingesta preestablecido, en cada animal se midió la concentración de glucosa alcanzada en la solución serosal de segmentos de intestino delgado evertidos, a los 20,40 y 60 minutos. Tomando estos valores como un indicador de la absorción intestinal de glucosa, se observó una menor concentración de ella en el grupo Oliva al comparar este con los grupos restantes, pero sólo fue estadísticamente significativo en relación con los grupos Rosa mosqueta y Coco (p<0.05). El comportamiento similar observado en los grupos alimentados con Rosa mosqueta y Coco, aceites con valores extremos y opuestos de insaturación, podríamos atribuirlo al desencadenamiento de mecanismos homeostáticos en la membrana celular de los enterocitos frente al estrés nutricional ocasionado por los ácidos grasos saturados e insaturados de dichos aceites. Podemos concluir que la absorción intestinal de glucosa in vitro en Hamster dorado se ve afectada por los lípidos de la dieta. La menos absorción de glucosa observada en el grupo Oliva podría ser el resultado de la acción específica de un ácido graso en particular o de su grado de insaturación