Effect of Mimosa pudica (mimosa)’s alcoholic extract on rat fertility

Objetivos: Determinar si la administración por vía oral del extracto etanólico de las hojas de Mimosa pudica (mimosa) modifica la fertilidad en ratas normales. Diseño: Estudio experimental. Institución: Instituto de Investigaciones Clínicas, Facultad de Medicina, Facultad de Farmacia, Universidad Nacional Mayor de San Marcos y Hospital Nacional Hipólito Unanue, Lima, Perú. Material biológico: Ratas albinas, y hojas de Mimosa pudica. Métodos: Cuarentiocho animales fueron divididos aleatoriamente en grupos de seis animales cada uno. El primero fue control, con solución de suero fisiológico 5 mL/kg, y los siguientes recibieron extracto vía oral 50, 250 y 500 mg/kg, durante 21 días. Cada grupo consideró 6 hembras y 6 machos juntos. Los animales fueron sacrificados para observar la presencia de fetos en el útero. A las hembras se les extrajo muestra de sangre, para conocer el nivel de FSH, estradiol y progesterona, expresándose en μg/dL. El dosaje hormonal se realizó por el método de electroquimioluminiscencia. En el estudio de antiimplantación se usó 2 grupos de 5 ratas hembras grávidas; un grupo recibió agua y el otro recibió el extracto de la planta, en dosis de 600 mg/ kg, durante 10 días. Principales medidas de resultados: Disminución del número de fetos y niveles hormonales. Resultados: Los flavonoides, compuestos fenólicos y taninos estuvieron en mayor cantidad en el extracto etanólico. Las ratas que recibieron 250 mg/kg presentaron mayor número de fetos, seguidas por las de 50 mg/kg; en tanto que con la dosis de 500 mg/kg disminuyó el número de fetos comparativamente con las ratas que no recibieron la planta; hubo incremento de FSH y de progesterona. Conclusiones: En condiciones experimentales se muestra que en dosis de hasta 250 mg/kg aumenta la fertilidad, pero a 500 mg se reduce la fertilidad en ratas normales.Objectives: To determine whether oral administration of Mimosa pudica (mimosa) leaves ethanol extract modifies fertility in normal rats. Design: Experimental study. Setting: Instituto de Investigaciones Clinicas, Facultad de Medicina, Facultad de Farmacia, Universidad Nacional Mayor de San Marcos, Hospital Nacional Hipolito Unanue, Lima, Peru. Biological material: Albino rats and Mimosa pudica leaves. Methods: Forty-eight animals were divided randomly into groups of six animals each. The first was control and received saline solution 5 mL/kg and the others 50, 250 and 500 mg/kg oral extracts for 28 days. Each group considered 6 males and 6 females together. The animals were killed to observe the presence of fetuses in uterus. FSH, estradiol and progesterone levels were determined in μg /dL in female rats’ blood samples and hormone dosage was done by electrochemoluminiscence method. In the antiimplantation study 2 groups of 5 pregnant female rats were used; one group received water and the other 600 mg/kg plant extract doses for 10 days. Main outcome measures: Reduction in the number of fetuses and hormone levels. Results: Flavonoids, phenolics and tannins were in larger quantity in the ethanol extract. Rats that received 250 mg/kg showed a greater number of fetuses followed by 50 mg/kg, while 500 mg/kg dose decreased the number of fetuses as compared with rats not given the plant; FSH and progesterone showed increased levels. Conclusions: In experimental conditions Mimosa pudica’s 250 mg/kg doses increased fertility but 500 mg reduced fertility in normal rats

Copaifera officinalis oil cytoprotector and antisecretory effects in induced gastric lesions in rats

Objetivos: Demostrar el efecto gastroprotector del aceite de Copaifera officinalis usando indometacina y ligadura de píloro en ratas. Diseño: Estudio preclínico. Lugar: Facultades de Medicina, de Farmacia y Bioquímica. Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Ratas y aceite de copaiba. Intervenciones: Se colectó el aceite de copaiba en Ucayali, Pucallpa. La citoproteccción fue evaluada con indometacina, considerando un grupo control normal, indometacina, grupos de aceite de copaiba y omeprazol. Las lesiones de la mucosa gástrica fueron calificadas como las compatibles con necrosis local (tejido no viable), hiperemia, enrojecimiento presente y hemorragia, empleando la escala de puntaje observacional; y la úlcera, según la escala de Macallister modificado. El ensayo de antisecreción fue realizado por el modelo de ligadura del píloro, en el que 24 ratas albinas fueron divididas al azar en 3 grupos; un control, otro de aceite de copaiba 40mg/kg y un tercero de omeprazol 10 mg/kg. Después de 4 horas de ligazón, fueron sacrificados, extrayéndose los estómagos; con mucho cuidado se midió el volumen y se determinó el pH de la secreción gástrica, por potenciometría. Se realizó evaluación histopatológica según Devi. Principales medidas de resultados: Lesiones ulcerosas. Resultados: Los resultados indicaron 100% de efecto citoprotector con el aceite de copaiba y de 97,8% para el omeprazol (p<0,0001), ratificado con los hallazgos histopatológicos; la disminución del volumen de secreción fue 79,4% para omeprazol y 42,8% para el aceite de copaiba (p<0,001), con incremento del pH. Conclusiones: En condiciones experimentales, el aceite de copaiba fue efectivo como agente gastroprotector en ratas con inducción de úlcera gástrica.Objetives: To determine the gastroprotector effect of Copaifera officinalis oil using indomethacin and pyloric ligature in rats. Design: Preclinical study. Setting: Faculties of Medicine, Pharmacy and Biochemistry, National University of San Marcos, Lima, Peru. Biological material: Rats and copaiba oil. Interventions: Copaiba oil was collected in Ucayali, Pucallpa. Cytoprotection was tested with indomethacin considering a normal control group, and indomethacin, copaiba and omeprazole groups. Using visual analogue scale mucosa gastric injuries were referred as those compatible with local necrosis (unviable tissue), hyperemia, flushing, and hemorrhage, and ulcers according to the modified Macallister’s scale. The anti-secretion trial used the pyloric ligature model. Twenty-four albino rats were randomized in three groups: control, copaiba oil 40 mg/kg and omeprazole 10 mg/kg, respectively. After 4 hours of linkage, they were sacrificed. Stomachs were removed, their volume measured carefully and gastric secretion pH determined by potentiometry. Devis’s histopathological evaluation was used. Main outcome measures: Ulcerous injuries. Results: There was 100% cytoprotection with copaiba oil and 97,8% with omeprazole (p<0,0001), ratified by histological findings. Decrease in secretion volume was 79,4% for omeprazole and 42,8% for copaiba oil (p<0,0001) with pH increment. Conclusions: In experimental conditions copaiba oil was effective as gastroprotective agent in gastric ulcers-induced rats

Preventive effect of Oenothera rosea on N-methyl-N-nitrosourea- (NMU) induced gastric cancer in rats

Background: Currently, gastric cancer (GC) is considered a public health problem worldwide. Using medicinal plants for the prevention of chronic diseases such as cancer constitutes new alternatives in traditional medicine. Oenothera rosea (OR) could be an option, but it needs to be evaluated. Aim: The main objective of this study was to evaluate the protective effect of OR extract on N-methyl-N-nitrosourea (NMU)-induced GC in rats. Methods: In total, 80 male Holtzman rats were randomized into five groups. Group A received the saline solution (5mL/kg), group B received NMU 500 μg/kg (cancer inductor) by oral administration for 16 weeks, and groups C, D, and E were treated with OR extract (100, 200, and 300 mg/kg, respectively) and NMU in order to evaluate the preventive effect on cancer induced by NMU for 16 weeks. Blood and histological samples of stomachs were collected to determine histopathological, biochemical, and hematological parameters between different experimental groups. Results: Groups C, D, and E presented less histopathological changes such as anaplastic and hyperplastic cells, compared with group B. Hematological and biochemical parameters were recorded, and superoxide dismutase, malondialdehyde, and nitric oxide levels were statistically less than those of NMU group (P<0.05, P<0.01, and P<0.01). Conclusion: Considering the histopathological signs and the antioxidant activity in vivo as well as hematological and biochemical parameters of ethanolic extract of OR, we concluded that its administration in rats has a protective effect on GC, which is induced experimentally. This species could be studied in clinical trials for patients with GC in the future.Revisión por pare

Efecto protector en cirrosis hepática inducida en ratas del extracto etanólico de las hojas de Piper aduncum comparado con silimarina

Objectives: To determine the protective effect of Piper aduncum (matico) leaves ethanol extract and its phytomedicine in capsules in liver cirrhosis induced in rats. Design: Experimental. Location: Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biological material: Leaves of Piper aduncum, and Rattus norvegicus, Holtzman strain. Interventions: The leaves were collected in La Merced district, Pasco department. The phytomedicine capsules were prepared from the plant ethanol extract. Cirrhosis was induced with phenobarbital 0.5 mg/mL diluted in drinking water during 15 days, then carbon tetrachloride 0.2mL/kg 1:1 in olive oil orally during 7 days. Blood samples were drawn in order to determine liver profile and malondialdehyde; the animals were sacrificed, extracting the liver for pathology study. Data were evaluated by multivariate techniques with p &lt;0.05. Main outcome measures: Degree of liver injury, biochemical marks, oxidative stress. Results: About 200 mg/kg of both extract and phytomedicine decreased ALT values (p &lt; 0.621), total bilirrubin (p &lt; 0.385) and direct bilirrubin (p &lt; 0.283) and increased total protein (p &lt;0.539) and albumin (p &lt;0.114), similar to silymarin group. Collagen, fibrosis and liver damage degree increased with carbon tetrachloride, and reduced with the different treatments and silymarin. Oxidative stress marker was also reduced with the applied treatments (p &lt;0.002). Conclusions: Piper aduncum (matico) leaves ethanol extract and its phytomedicine had protective effect of cirrhosis induced in rats similar to silymarin.Objetivos: Evaluar la eficacia protectora del extracto etanólico de hojas de Piper aduncum (matico) y su fitomedicamento en cápsulas, en la cirrosis hepática inducida en ratas. Diseño: Experimental. Lugar: Facultad Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Hojas de Piper aduncum, y Rattus norvegicus, cepa Holtzman. Intervenciones: Las hojas fueron recolectadas en el distrito de Huariaca, departamento de Pasco. El fitomedicamento en cápsulas se preparó a partir del extracto etanólico de la planta. La cirrosis fue inducida con fenobarbital 0,5 mg/mL, diluida en el agua de beber por 15 días, y luego, tetracloruro de carbono 0,2mL/kg en aceite de oliva 1:1, oralmente por 7 días. Se colectó una muestra de sangre para determinar perfil hepático y malondialdehído; los animales fueron sacrificados extrayéndose el hígado para estudio histopatológico. Los datos fueron evaluados mediante técnicas multivariadas, con valor p &lt; 0,05. Principales medidas de resultados: Grado de lesión hepática, marcadores bioquímicos, estrés oxidativo. Resultados: El extracto y el fitomedicamento a 200 mg/kg disminuyeron los valores de TGP (p &lt; 0,621), bilirrubina total (p &lt; 0,385) y bilirrubina directa (p &lt; 0,283) e incrementaron las proteínas totales (p &lt; 0,539) y albúmina (p &lt; 0,114), similar al grupo silimarina. El colágeno, la fibrosis y el nivel de daño hepático se vieron aumentados con tetracloruro de carbono; estos indicadores se redujeron con los diferentes tratamientos y la silimarina. El marcador de estrés oxidativo se redujo con los tratamientos aplicados (p &lt; 0,002). Conclusiones: El extracto etanólico de las hojas de Piper aduncum (matico) y su fitomedicamento ejercieron efecto protector de la cirrosis inducida en ratas, comparativamente con la silimarina

Cicatrizing effect of Copaifera officinalis (copaiba) oil in patients with peptic ulcer

Objetivos: Determinar la eficacia cicatrizante del aceite de copaiba obtenido de la corteza de Copaifera officinalis, comparado con omeprazol 20 mg, en pacientes con diagnóstico definitivo de úlcera péptica. Diseño: Estudio experimental, clínico comparativo, de fase II, aleatorio, doble ciego, grupo paralelo. Institución: Instituto de Investigaciones Clínicas, Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Participantes: Pacientes con diagnóstico definitivo de úlcera péptica. Intervenciones: El diagnóstico fue tanto por exploración física como complementaria, siendo la endoscopia la técnica de elección, con evaluación pre y postratamiento con aceite de copaiba, formulada en cápsulas de 80 mg y 120 mg. El ensayo clínico incluyó 60 pacientes que voluntariamente ingresaron al programa de estudio, previa firma del consentimiento informado aprobado por el Comité institucional de Ética en Investigación. Los pacientes fueron distribuidos aleatoriamente en tres grupos, de 20 casos cada uno, según orden de llegada; los dos primeros grupos recibieron cápsulas de aceite de copaiba, en dosis de 80 y 120 mg, respectivamente; y un tercer grupo recibió omeprazol 20 mg. Los tratamientos fueron administrados en ayunas, una vez por la mañana, 30 minutos antes de la ingesta del primer alimento. Los datos fueron evaluados mediante técnicas multivariadas, considerando estadísticamente significativo p&lt;0,05. Se tuvo en cuenta el consentimiento informado aprobado por el Comité de Bioética en Investigación del Centro Asistencial. Principales medidas de resultados: Porcentaje de cicatrización. Resultados: Se logró 65% y 75% de cicatrización de la úlcera péptica con aceite de copaiba, respectivamente, contra 100% en el grupo de omeprazol, sin efectos adversos significativos; dos presentaron náuseas y tres epigastralgia. Conclusiones: Los pacientes con úlcera péptica y con tratamiento de las cápsulas conteniendo aceite de copaiba mostraron cicatrización de la úlcera de 65 a 75% y sin efectos adversos significativos.Objectives: To determine the cicatrizing effect of Copaifera officinalis’ stem bark copaiba oil compared with omeprazole 20 mg in patients with diagnosis of peptic ulcer. Design: Experimental, comparative, phase II, randomized, double-blind, parallel-group clinical trial. Setting: Clinical Investigation Institute, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Participants: Patients with diagnosis of peptic ulcer. Interventions: Clinical diagnosis of peptic ulcer was done by endoscopy as well as pre and post treatment evaluation following administration of copaiba oil formulated capsules (80 mg and 120 mg). Sixty patients enrolled voluntarily to the study and signed informed consent as approved by the Institutional Review Board. Patients were randomly distributed in three groups of 20 cases each according to arrival order; the first and second group received respectively copaiba oil 80 mg and 120 mg capsules, and the third group omeprazole 20 mg, fasting, once daily in the morning, half hour before breakfast. Data was evaluated through multivariate techniques, considering p&lt;0.05 as statistically significant. Main outcome measures: Percentage of patients healing their ulcer. Results: Peptic ulcer cicatrized in 65% and 75% respectively versus 100% in the omeprazole group, without significant adverse effects. Two patients presented nausea and three epigastric pain. Conclusions: Patients with peptic ulcer treated with copaiba oil capsules showed ulcer scarring in 65% to 75% and without significant adverse effects

Ionic-to-electronic current amplification in hybrid perovskite solar cells: ionically gated transistor-interface circuit model explains hysteresis and impedance of mixed conducting devices

Mobile ions in hybrid perovskite semiconductors introduce a new degree of freedom to electronic devices suggesting applications beyond photovoltaics. An intuitive device model describing the interplay between ionic and electronic charge transfer is needed to unlock the full potential of the technology. We describe the perovskite-contact interfaces as transistors which couple ionic charge redistribution to energetic barriers controlling electronic injection and recombination. This reveals an amplification factor between the out of phase electronic current and the ionic current. Our findings suggest a strategy to design thin film electronic components with large, tuneable, capacitor-like and inductor-like characteristics. The resulting simple equivalent circuit model, which we verified with time-dependent drift-diffusion simulations of measured impedance spectra, allows a general description and interpretation of perovskite solar cell behaviour

Real-Time Observation of Iodide Ion Migration in Methylammonium Lead Halide Perovskites

Organic-inorganic metal-halide perovskites (e.g. CH3NH3PbI3-xClx) emerged as a promising opto-electronic material. However, the Shockley–Queisser Limit for the power conversion efficiency (PCE) of perovskite-based photovoltaic devices has still not been reached, which was attributed to non-radiative recombination pathways, as suggested by photoluminescence (PL) inactive (or dark) areas on perovskite films. Although these observations have been related to the presence of ions/defects, the underlying fundamental physics and detailed microscopic processes, concerning trap/defect status, ion migration, etc., still remain poorly understood. Here we utilize correlated wide-field PL microscopy and impedance spectroscopy (IS) on perovskite films to in-situ investigate both the spatial and temporal evolution of these PL inactive areas under external electrical fields. We attribute the formation of PL inactive domains to the migration and accumulation of iodine ions under external fields. Hence we are able to characterize the kinetic processes and determine the drift velocities of these ions. In addition, we show that I2 vapor directly affects the PL quenching of a perovskite film, which provides evidence that the migration/segregation of iodide ions plays an important role in the PL quenching and consequently limits the PCE of organometal halide based perovskite photovoltaic devices

Interpretation of inverted photocurrent transients in organic lead halide perovskite solar cells: proof of the field screening by mobile ions and determination of the space charge layer widths

In Methyl Ammonium Lead Iodide (MAPI) perovskite solar cells, screening of the built-in field by mobile ions has been proposed as part of the cause of the large hysteresis observed in the current/voltage scans in many cells. We show that photocurrent transients measured immediately (e.g. 100 μs) after a voltage step can provide direct evidence that this field screening exists. Just after a step to forward bias, the photocurrent transients are reversed in sign (i.e. inverted), and the magnitude of the inverted transients can be used to find an upper bound on the width of the space charge layers adjacent to the electrodes. This in turn provides a lower bound on the mobile charge concentration, which we find to be ≳1 × 1017 cm−3. Using a new photocurrent transient experiment, we show that the space charge layer thickness remains approximately constant as a function of bias, as expected for mobile ions in a solid electrolyte. We also discuss additional characteristics of the inverted photocurrent transients that imply either an unusually stable deep trapping, or a photo effect on the mobile ion conductivity

Controlled synthesis of monodisperse gold nanorods with different aspect ratios in the presence of aromatic additives

This paper reports the synthesis of monodisperse gold nanorods (GNRs) via a simple seeded growth approach in the presence of different aromatic additives, such as 7-bromo-3-hydroxy-2-naphthoic acid (7-BrHNA), 3-hydroxy-2-naphthoic acid (HNA), 5-bromosalicylic acid (5-BrSA), salicylic acid (SA) or phenol (PhOH). Effects of the aromatic additives and hydrochloric acid (HCl) on the structure and optical properties of the synthesized GNRs were investigated. The longitudinal surface plasmon resonance (LSPR) peak wavelength of the resulting GNRs was found to be dependent on the aromatic additive in the following sequence: 5-BrSA (778 nm) > 7-BrHNA (706 nm) > SA (688 nm) > HNA (676 nm) > PhOH (638 nm) without addition of HCl, but this was changed to 7-BrHNA (920 nm) > SA (890 nm) > HNA (872 nm) > PhOH (858 nm) > 5-BrSA (816 nm) or 7-BrHNA (1005 nm) > PhOH (995 nm) > SA (990 nm) > HNA (980 nm) > 5-BrSA (815 nm) with the addition of HCl or HNO3 respectively. The LSPR peak wavelength was increased with the increasing concentration of 7-BrHNA without HCl addition, however, there was a maximum LSPR peak wavelength when HCl was added. Interestingly, the LSPR peak wavelength was also increased with amount of HCl added. The results presented here thus established a simple approach to synthesize monodisperse GNRs of different LSPR wavelength