Overexpression of mitochondrial fission or mitochondrial fusion genes enhances resilience and extends longevity.

The dynamicity of the mitochondrial network is crucial for meeting the ever-changing metabolic and energy needs of the cell. Mitochondrial fission promotes the degradation and distribution of mitochondria, while mitochondrial fusion maintains mitochondrial function through the complementation of mitochondrial components. Previously, we have reported that mitochondrial networks are tubular, interconnected, and well-organized in young, healthy C. elegans, but become fragmented and disorganized with advancing age and in models of age-associated neurodegenerative disease. In this work, we examine the effects of increasing mitochondrial fission or mitochondrial fusion capacity by ubiquitously overexpressing the mitochondrial fission gene drp-1 or the mitochondrial fusion genes fzo-1 and eat-3, individually or in combination. We then measured mitochondrial function, mitochondrial network morphology, physiologic rates, stress resistance, and lifespan. Surprisingly, we found that overexpression of either mitochondrial fission or fusion machinery both resulted in an increase in mitochondrial fragmentation. Similarly, both mitochondrial fission and mitochondrial fusion overexpression strains have extended lifespans and increased stress resistance, which in the case of the mitochondrial fusion overexpression strains appears to be at least partially due to the upregulation of multiple pathways of cellular resilience in these strains. Overall, our work demonstrates that increasing the expression of mitochondrial fission or fusion genes extends lifespan and improves biological resilience without promoting the maintenance of a youthful mitochondrial network morphology. This work highlights the importance of the mitochondria for both resilience and longevity.

Gut microbial features and dietary fiber intake predict gut microbiota response to resistant starch supplementation.

Resistant starch (RS) consumption can have beneficial effects on metabolic health, but the response, in terms of effects on the gut microbiota and host physiology, varies between individuals. Factors predicting the response to RS are not yet established and would be useful for developing precision nutrition approaches that maximize the benefits of dietary fiber intake. We sought to identify predictors of gut microbiota response to RS supplementation. We enrolled 76 healthy adults into a 7-week crossover study with 59 individuals completing the study. Participants consumed RS type 2 (RS2), RS type 4 (RS4), and digestible starch, for 10 d each with 5-d washout periods in between. We collected fecal and saliva samples and food records during each treatment period. We performed 16S rRNA gene sequencing and measured fecal short-chain fatty acids (SCFAs), salivary amylase (AMY1) gene copy number, and salivary amylase activity (SAA). Dietary fiber intake was predictive of the relative abundance of several amplicon sequence variants (ASVs) at the end of both RS treatments. AMY1-related metrics were not predictive of response to RS. SAA was only predictive of the relative abundance of one ASV after digestible starch supplementation. Interestingly, SCFA concentrations increased the most during digestible starch supplementation. Treatment order (the order of consumption of RS2 and RS4), alpha diversity, and a subset of ASVs were predictive of SCFA changes after RS supplementation. Based on our findings, dietary fiber intake and gut microbiome composition would be informative if assessed prior to recommending RS supplementation because these data can be used to predict changes in specific ASVs and fecal SCFA concentrations. These findings lay a foundation to support the premise that using a precision nutrition approach to optimize the benefits of dietary fibers such as RS could be an effective strategy to compensate for the low consumption of dietary fiber nationwide.

Four Atypical Cases of Subclinical Rhythmic Electroencephalogram Discharge of Adults: Case Series and Review.

SUMMARY: Subclinical rhythmic EEG discharge of adults is an uncommon variant that represents a diagnostic challenge in the clinical practice because it can be mistaken for an electrographic seizure. We present a case series of four patients who underwent EEG because of suspicious events or an unclear medical history of epilepsy. In all cases, the EEG revealed atypical features including focal and asymmetric distribution, presentation during NREM and REM sleep, rhythmic activity in the delta range with a notched appearance and blocked by eyes opening.

Genetic Variants in One-Carbon Metabolism and Their Effects on DHA Biomarkers in Pregnant Women: A Post-Hoc Analysis.

The delivery of docosahexanoic acid (DHA) to the fetus is dependent on maternal one-carbon metabolism, as the latter supports the hepatic synthesis and export of a DHA-enriched phosphatidylcholine molecule via the phosphatidylethanolamine N-methyltransferase (PEMT) pathway. The following is a post-hoc analysis of a choline intervention study that sought to investigate whether common variants in one-carbon metabolizing genes associate with maternal and/or fetal blood biomarkers of DHA status. Pregnant women entering their second trimester were randomized to consume, until delivery, either 25 (n = 15) or 550 (n = 15) mg choline/d, and the effects of genetic variants in the PEMT, BHMT, MTHFD1, and MTHFR genes on DHA status were examined. Variant (vs. non-variant) maternal PEMT rs4646343 genotypes tended to have lower maternal RBC DHA (% total fatty acids) throughout gestation (6.9% vs. 7.4%; main effect, p = 0.08) and lower cord RBC DHA at delivery (7.6% vs. 8.4%; main effect, p = 0.09). Conversely, variant (vs. non-variant) maternal MTHFD1 rs2235226 genotypes exhibited higher cord RBC DHA (8.3% vs. 7.3%; main effect, p = 0.0003) and higher cord plasma DHA (55 vs. 41 µg/mL; main effect, p = 0.05). Genotype tended to interact with maternal choline intake (p < 0.1) to influence newborn DHA status for PEMT rs4646343 and PEMT rs7946. These data support the need to consider variants in one-carbon metabolic genes in studies assessing DHA status and requirements during pregnancy.

Seroprevalence and risk factors associated with bovine herpesvirus 1 in dairy herds of Colombia.

Background and Aim: Infectious bovine rhinotracheitis (IBR) is an infectious disease widely distributed globally and is considered the main cause of various reproductive and respiratory tract diseases in cattle and buffaloes. This study aimed to estimate seroprevalence and determine risk factors associated with the presentation of IBR in the municipality of Sotaquirá, Boyacá (Colombia). Materials and Methods: A descriptive cross-sectional study with simple random sampling was performed, and the sample size was 1,000 cattle. Blood samples were obtained by coccygeal venipuncture and processed through indirect enzyme-linked immunosorbent assay using the Synbiotics® kit (Zoetis, New Jersey, USA) with a sensitivity and specificity of 96% and 98%, respectively. Data were processed using the statistical program EpiInfo® (Centers for Disease Control and Prevention; Atlanta, Georgia). Results: A high seroprevalence of 57.5% was established. Seroprevalence was the highest in cattle >4 years of age (65.0% apparent seroprevalence [AS]; 67% true seroprevalence [TS]) and in the Holstein breed (65.5% AS; 67.8% TS). The breed and age of the animals were significantly associated with each other. The Holstein breed, age group >4 years, uncertified semen, and fetal death were established as risk factors for IBR. In comparison, the age groups of <1 and 1-2 years and the Normande breed were established as protective factors against the bovine herpesvirus-1 virus. Conclusion: Management factors, such as livestock from other owners and animal purchases, which affect disease presentation, are evident. The implementation and development of novel prevention and control measures for IBR at the national level are necessary.

Prenatal choline supplementation improves biomarkers of maternal docosahexaenoic acid (DHA) status among pregnant participants consuming supplemental DHA: a randomized controlled trial.

BACKGROUND: Dietary methyl donors (e.g., choline) support the activity of the phosphatidylethanolamine N-methyltransferase (PEMT) pathway, which generates phosphatidylcholine (PC) molecules enriched in DHA that are exported from the liver and made available to extrahepatic tissues. OBJECTIVES: This study investigated the effect of prenatal choline supplementation on biomarkers of DHA status among pregnant participants consuming supplemental DHA. METHODS: Pregnant participants (n = 30) were randomly assigned to receive supplemental choline intakes of 550 mg/d [500 mg/d d0-choline + 50 mg/d deuterium-labeled choline (d9-choline); intervention] or 25 mg/d (25 mg/d d9-choline; control) from gestational week (GW) 12-16 until delivery. All participants received a daily 200-mg DHA supplement and consumed self-selected diets. Fasting blood samples were obtained at baseline, GW 20-24, and GW 28-32; maternal/cord blood was obtained at delivery. Mixed-effects linear models were used to assess the impact of prenatal choline supplementation on maternal and newborn DHA status. RESULTS: Choline supplementation (550 vs. 25 mg/d) did not achieve a statistically significant intervention × time interaction for RBC PC-DHA (P = 0.11); a significant interaction was observed for plasma PC-DHA and RBC total DHA, with choline supplementation yielding higher levels (+32-38% and +8-11%, respectively) at GW 28-32 (P < 0.05) and delivery (P < 0.005). A main effect of choline supplementation on plasma total DHA was also observed (P = 0.018); its interaction with time was not significant (P = 0.068). Compared with controls, the intervention group exhibited higher (P = 0.007; main effect) plasma enrichment of d3-PC (d3-PC/total PC). Moreover, the ratio of d3-PC to d9-PC was higher (+50-67%; P < 0.001) in the choline intervention arm (vs. control) at GW 20-24, GW 28-32, and delivery. CONCLUSIONS: Prenatal choline supplementation improves hepatic DHA export and biomarkers of DHA status by bolstering methyl group supply for PEMT activity among pregnant participants consuming supplemental DHA. This trial is registered at www.clinicaltrials.gov as NCT03194659.

Immune system modulation in aging: Molecular mechanisms and therapeutic targets.

The function of the immune system declines during aging, compromising its response against pathogens, a phenomenon termed as "immunosenescence." Alterations of the immune system undergone by aged individuals include thymic involution, defective memory T cells, impaired activation of naïve T cells, and weak memory response. Age-linked alterations of the innate immunity comprise perturbed chemotactic, phagocytic, and natural killing functions, as well as impaired antigen presentation. Overall, these alterations result in chronic low-grade inflammation (inflammaging) that negatively impacts health of elderly people. In this review, we address the most relevant molecules and mechanisms that regulate the relationship between immunosenescence and inflammaging and provide an updated description of the therapeutic strategies aimed to improve immunity in aged individuals.

Single-shot spatial coherence characterization of x-ray ultrafast sources.

Spatial coherence is an impactful source parameter in many applications ranging from atomic and molecular physics to metrology or imaging. In lensless imaging, for example, it can strongly affect the image formation, especially when the source exhibits shot-to-shot variations. Single-shot characterization of the spatial coherence length of a source is thus crucial. However, current techniques require either parallel intensity measurements or the use of several masks. Based on the method proposed by González et al. [J. Opt. Soc. Am. A28, 1107 (2011)JOAOD60740-323210.1364/JOSAA.28.001107], we designed a specific arrangement of a two-dimensional non-redundant array of apertures, which allows, through its far field interference pattern, for a single-shot measurement of the spatial coherence, while being robust against beam-pointing instabilities. The strategic configuration of the pinholes allows us to disentangle the degree of spatial coherence from the intensity distribution, thus removing the need for parallel measurement of the beam intensity. An experimental validation is performed using a high-harmonic source. A statistical study in different regimes shows the robustness of the method.

Determinación de Rinotraqueítis Infecciona Bovina (BHV-1) en el municipio de Toca, Boyacá / Determination of Infectious Bovine Rhinotracheitis (BHV-1) in the municipality of Toca, Boyacá / Determinação de Rinotraqueíte Infecciosa Bovina (BHV-1) na municipalidade de Toca, Boyacá

Resumen Introduction La Rinotraqueítis Infecciosa Bovina (RIB) es una enfermedad infectocontagiosa que afecta principalmente a bovinos y bufalinos, encontrándose ampliamente distribuida a nivel mundial, siendo una de las principales causas de perdidas económica y físicas en las producciones. Objetivo. determinar la prevalencia de la Rinotraqueítis Infecciosa Bovina (BHV-1) en el municipio de Toca, Boyacá. Materiales y métodos. Se recolectaron 350 muestras de sangre Bovina, las cuales fueron procesadas en el laboratorio de la Universidad Pedagógica y Tecnológica de Colombia, mediante un kit comercial de ELISA. Resultados. La prevalencia para IBR, en el municipio de Toca, Boyacá, fue de 65,5%. No se encontró relación significativa con las variables estudiadas como abortos, distocias, no gestantes, repetición de celos, entre otras. Conclusión. La Rinotraqueítis Infecciosa Bovina es una de las principales causas de pérdidas económicas y físicas en las diversas producciones, sin embargo, no siempre es la principal causa de alteraciones reproductivas presentes en los bovinos.

Abstract Introduction Infectious Bovine Rhinotracheitis (IBR) is an Infectious contagious disease that mainly affects cattle and bufalin, being widely distributed worldwide, being one of the main causes of economic and physical losses in production. Objective. Determine the prevalence of Infectious Bovine Rhinotracheitis (BHV-1) in the municipality of Toca, Boyacá. Materials and methods. 350 Bovine blood samples were collected, which were processed in the laboratory of Universidad Pedagógica y Tecnológica de Colombia, through a commercial kit of ELISA. Results. The prevalence for IBR, in the municipality of Toca, Boyacá, was 65.5%. No significant relationship was found with the variables studied such as abortions, dystocias, non-pregnant cattle, repetition of estrus, among others. Conclusion. Infectious Bovine Rhinotracheitis is one of the main causes of economic losses in the various productions, however, it is not always the main cause of reproductive alterations present in Bovines.

Resumo Introdução A Rinotraqueíte Infecciosa Bovina (RIB) é uma doença infectocontagiosa que afeta principalmente os bovinos e bufalinos, estando amplamente distribuída a nível mundial, sendo uma das principais causas de perda económica e física nas produções. Objetivo. Determinar a prevalência da Rinotraqueíte Infecciosa Bovina (BHV-1) no município de Toca, Boyacá. Materiais e métodos. Recolheram-se 350 amostras de sangue de bovinos, que foram processadas no laboratório da Universidad Pedagógica y Tecnológica de Colombia, pelo kit comercial de ELISA. Resultados. A prevalência de IBR, no município de Toca, Boyacá, foi de 65,5 %. Não se encontrou relação significativa com as variáveis estudadas como abortos, distocias, não gestantes, repetição de cios, entre outras. Conclusão. A Rinotraqueíte Infecciosa Bovina é uma das principais causas de perda económica e física nas diversas produções, no entanto, não sempre é a principal causa de alterações reprodutivas presentes nos bovinos.

Vasculitis primaria del sistema nervioso central, un reto diagnóstico. Reporte de caso / Primary vasculitis of the central nervous system, a diagnostic challenge. Case report

RESUMEN La angeítis primaria del sistema es una rara entidad, en la cual hay destrucción y compromiso inflamatorio de los vasos del sistema nervioso central. Con frecuencia, es subdiagnosticada por sus múltiples formas de presentación clínica y por los hallazgos en neuroimágenes que pueden simular otras patologías, lo que retrasa el diagnóstico y el manejo oportuno. Este tipo de vasculitis es muy poco comprendida y no existen suficientes estudios en la actualidad respecto a su fisiopatología y manejo. Los marcadores inflamatorios suelen ser normales, con alteración del LCR en un 80-90 % de los casos y la arteriografía cerebral puede mostrar un patrón típico descrito como áreas alternantes de dilatación y estenosis; sin embargo, con muy baja sensibilidad. Ante una alta sospecha clínica y ausencia de pruebas diagnósticas no invasivas, el diagnóstico se realiza a través de biopsia de las lesiones cerebrales y meninges. Finalmente, el tratamiento se basa en combinación de corticoides y ciclofosfamida, aunque se carece de estudios controlados que lo soporten.

SUMMARY Primary angiitis of the central nervous system is a rare condition in which there is destruction and inflammatory involvement of the vessels of the central nervous system. It is often underdiagnosed given its multiple forms of clinical presentation and neuroimaging findings that can mimic other pathologies delaying diagnosis and management. This type of vasculitis is very poorly understood and there are not enough studies at present regarding the pathophysiology and management. Inflammatory markers are usually normal with abnormal CSF in 80-90 %% of cases and cerebral arteriography may show a typical pattern described as in "Rosario" however with very low sensitivity. Given the persistence of high clinical and absence of non-invasive diagnostic tests suspect the final diagnosis is made by biopsy of brain lesions and meninges. Finally, treatment is based on a combination of corticosteroids and cyclophosphamide however has not controlled studies support it.

Síndrome de Melas: correlación clínica con hallazgos imagenológicos en espectroscopia y tractografía, reporte de caso / Melas syndrome: clinical correlation with imaging findings in spectroscopy and tractography, case report

El síndrome de Melas es una enfermedad de herencia mitocondrial caracterizada por encefalopatía mitocondrial, acidosis láctica y eventos similares a ataque cerebrovascular, secundaria a una mutación en los genes que codifican las proteínas transportadoras de electrones, limitando la producción energética y generando disfunción multiorgánica, que afecta principalmente el sistema músculo esquelético y el sistema nervioso, lo que está en correlación con las características clínicas que presentan los pacientes. El diagnostico se basa en la sospecha clínica, los hallazgos paraclínicos e imagenológicos y la confirmación de la mutación a través del estudio genético. No existe tratamiento específico, se basa únicamente en el manejo sintomático y requiere apoyo multidisciplinario. Presentamos el caso de un paciente con antecedente de Melas, que ingresó por evento cerebrovascular isquémico bioccipital y correlación con hallazgos en neuroimágenes (espectroscopia y tractografía).

Melas syndrome is a disease characterized by mitochondrial inheritance of mitochondrial encephalopathy, lactic acidosis and events like stroke secondary to a mutation in the gene encoding the electron transport proteins limiting energy production and generating multiorgan dysfunction being affected mainly musculoskeletal system and the nervous system which correlates with the clinical characteristics presented by patients. The diagnosis is based on clinical suspicion, laboratory, and imaging findings and confirmation of the mutation through genetic study. No specific treatment is Is available, but symptomatic treatment is needed and requires multidisciplinary support. We report a patient with a history of Melas who who had bioccipital cerebral ischemic event and correlation with findings in neuroimaging (spectroscopy and tractography).

La Cascada de la adherencia a la atención integral al tratamiento antirretroviral en Guatemala y factores institucionales que influyen en su evaluación / The Cascade of the integral attention to the treatment antiretroviral treatment in Guatemala and institutional factors that influence your evaluation

Introducción: La implementación de la terapia antirretroviral (TAR) en Centroamérica ha tenido un desarrollo diferente en cada país. En Guatemala en la última década, se ha ampliado sus coberturas de manera importante y por el apoyo inicial de Médicos sin Fronteras y luego con los Recursos del Fondo Mundial de Lucha contra el Sida, Malaria y Tuberculosis, y el progresivo aumento de la inversión por parte del Ministerio de Salud y el Seguro social, el acceso al TAR es una realidad. Sin embargo, con los conceptos de acceso universal al diagnóstico y tratamiento, y buscando llegar a los estándares propuestos por la Cascada o Continuum de Adherencia a la Atención integral y el TAR, una evaluación de su estado actual, se hizo necesaria. Objetivos: Desarrollar un diagnóstico de situación del estado de la adherencia al tratamiento ARV y establecer los componentes de la cascada de atención, relacionados con la adherencia en Guatemala. Métodos: Como parte Proyecto CAMPLUS y con la coordinación de Proyecto Capacity-USAID Guatemala, con expertos locales, se desarrolló una guía para establecer el cumplimiento de TAR, utilizando la carga viral y para documentar la cascada de adherencia al tratamiento del VIH, en Guatemala...(AU)

Percretismo placentario asociado con placenta previa y abruptio: reporte de un caso / Placenta percreta associated with placenta previa and abruptio: a case report

El número de partos por cesárea ha aumentado durante los últimos años. Esto se ha relacionado con un incremento en las anormalidades de la inserción placentaria para embarazos futuros, así como de otras complicaciones feto-placentarias. Las patologías placentarias y el manejo quirúrgico que suelen requerir ensombrecen drásticamente el pronóstico materno-fetal. Reportamos un caso de una mujer multípara quien cursa con un caso de percretismo placentario, placenta previa y abruptio de placenta, que ingresó en el servicio de ginecoobstetricia en un hospital universitario siendo sometida a manejo quirúrgico multidisciplinario de urgencia obteniendo resultados materno-fetales satisfactorios (AU)

The number of cesarean sections has risen during the recent years, leading to an increase in abnormal placentation in future pregnancies, as well as other materno-fetal complications. Placental abnormalities and the surgical management they usually required, drastically obscure maternal and fetal outcomes. We report the case of a multiparous woman admitted to labor and delivery service of a university hospital presenting with placenta percreta, placenta previa and abruptio placentae. She received opportune emergency multidisciplinary management, obtaining satisfactory (AU)

Angiomiolipoma renal con rotura espontánea (síndrome de Wünderlich): Presentación de un caso / Renal Angiomyolipoma with Spontaneous Rupture (Wunderlich Syndrome): A Case report

El angiomiolipoma renal es el tumor mesenquimal benigno más común, y representa el 3 % de los tumores renales. Es más frecuente en mujeres y puede presentarse de forma esporádica o asociado al complejo de esclerosis tuberosa. Se presenta el caso de una paciente de 59 años de edad, sin antecedentes médicos de importancia, que consultó por dolor abdominal intenso. Al examen físico se detectó masa palpable en flanco derecho. En la tomografía axial computarizada (TAC) abdominal se demostró una masa retroperitoneal derecha heterogénea, con algunos acúmulos de grasa y sangrado activo que sugiere el diagnóstico de síndrome de Wünderlich asociado a angiomiolipoma. La resonancia magnética (RM) confirmó la dependencia de la masa del polo renal derecho y se descartó una invasión de la vena cava inferior. Se realizó embolización arterial selectiva renal derecha y nefrectomía parcial con evolución favorable. El angiomiolipoma renal con rotura espontánea es una entidad poco frecuente y potencialmente mortal. Debe ser considerado cuando en las imágenes diagnósticas se documenta una masa renal con focos de grasa y sangrado activo sin calcificaciones. El abordaje terapéutico debe ser multidisciplinario, con tendencia al tratamiento conservador.

Renal angiomyolipoma is the most common benign mesenchymal tumor, accounting for 3% of renal tumors, is more common in women and can occur sporadically or associated with tuberous sclerosis complex. A case of a 59 years old female patient is presented, with no medical history of importance, who consulted for severe abdominal pain and a palpable mass at the right flank during physical examination. Abdominal CT documented a right retroperitoneal heterogeneous mass, with some fat deposits, and active bleeding, suggesting the diagnosis of Wunderlich syndrome associated with angiomyolipoma. MRI confirmed the mass dependence of the right renal pole and Inferior Vein Cava (IVC) invasion is discarded. Selective renal arterial embolization and partial right nephrectomy was performed with favorable evolution. Renal angiomyolipoma with spontaneous rupture is a rare and potentially fatal entity. It should be considered when diagnostic imaging in the presence of renal mass with fatty areas and bleeding without calcification. The therapeutic approach should be multidisciplinary, with a tendency to conservative treatments.

Nonredundant array of apertures to measure the spatial coherence in two dimensions with only one interferogram.

We propose to use a mask with a nonredundant array (NRA) of multiple apertures to measure spatial coherence in two dimensions. The spatial distribution of the apertures in the mask is made in such a way that we obtain a quasi-uniform sampling in the coherence domain. The spatial coherence is obtained by Fourier transform of the interferogram generated by the mask when it is illuminated by the light field under analysis.

Estudio comparativo de estabilidad de tres formulaciones magistrales de Sildenafil bajo la forma de solución, obtenidas a partir de diferentes productos comerciales / Comparative study stability of the three master formulation of Sildenafil solution obtained from differents trademarks

El Sildenafil es un fármaco de comprobada actividad terapéutica en la disfunción eréctil; se encuentra disponible bajo la forma farmacéutica de tabletas de administración oral. En la actualidad se está formulando magistralmente en forma de so lución oral a una concentración de 1mg/ml, para la hipertensión pulmonar (HP), por lo que se ha planteado realizar un estudio de la estabilidad en tres condiciones: ambientales (25±-2 ºC), de refrigeración (5±3 ºC) y exageradas de almacenamiento (40 ºC ± 2 ºC). Los parámetros evaluados fueron apariencia, limpidez, densidad, pH y contenido de sildenafil. El método analítico empleado fue cromatografía líquida de alta resolución (HPLC) de fase reversa. La apariencia, los valores de pH y densidad de las soluciones obtenidas se mostraron sin cambios significativos, en las diferentes muestras y condiciones de estudio. En cuanto a los resultados del contenido inicial de sildenafil se obtuvo aproximadamente el 75% en peso al formular la solución, partiendo del comprimido. Cabe señalar que se observó discrepancia en los valores de concentración del sildenafil obtenidos en los diferentes tiempos y condiciones; resultados éstos de esperarse por tratarse de una formulación magistral que parte de comprimidos de diferentes casas comerciales, por lo que este estudio permitió sugerir que la formulación magistral se reformule a la forma farmacéutica de suspensión, para garantizar el contenido de todo el principio activo en la misma.

Sildenafil is a drug with proven therapeutic activity in erectile dysfunction is available under the pharmaceutical form of tablets for oral administration. It is currently being de veloped skillfully in an oral solution at a concentration of 1mg/ml, for pulmonary hypertension (pH), as has been planned to perform a study of stability in three conditions: environmental (25 ± 2 ºC), refrigeration (5 ± 3 ºC) and exaggerated storage (40 °C ± 2 ºC). The parameters evaluated were appearance, clarity, density, pH and content of sildenafil. The analytical method used was high performance liquid chromatography (HPLC) reverse phase. The appearance, pH and density of the solutions were no significant changes in the different samples and study conditions. As for the results of the initial content of sildenafil was obtained about 75% by weight in for mulating the solution, based on the tablet. It should be noted that there was discrepancy in the values of concentration of sildenafil obtained at different times and conditions, results they expected because it is a masterly formulation of tablets of different business houses, so this study suggest that the wording allowed masterful be reformulated to the pharmaceutical form of suspension, to ensure the contents of the entire active.

Effect of Fenton's reagent on O/W emulsions stabilized by black liquor.

The effect of Fenton's reagent (FR) on surface and dispersion properties of black liquor (BL) was investigated. These properties were compared to those of indulin C (IC), a commercial lignin, and egg lecithin (Le). FR was applied at two different bulk concentrations of H2O2 (160 and 320 mM). At pH 8, a minimum in surface tension for the Fenton treated BL was observed. The dispersant ability of BL, IC and Le in oil-in-water (O/W) emulsions was studied by measuring emulsion stability and drop size. It was found that the surface activity and emulsifying capability of BL were higher than those of IC. The emulsifying capability of Le was improved by the FR treatment at low H2O2 concentration.

Effect of surfactants on Fenton's reagent-mediated degradation of Kraft black liquor.

One of the limitations of the biodegradation of hydrophobic chemical compounds, like lignins, is their low solubility in the aqueous solution where this process takes place. To resolve this problem, surfactants have been used to improve the solubility of these hydrophobic compounds. In this investigation, we studied the effect of surfactants (anionic, cationic, and non-ionic) on the treatment of Kraft black liquor with Fenton's reagent. In the Fenton reaction, H2O2 (two different concentrations, 10 mM and 20 mM), FeCl2 (1 mM) and surfactant solution (10%) were used. Black liquor degradation was determined by UV/Visible spectrophotometry and by measuring phenolic groups. In the presence of Fenton's reagent, the optimum conditions for the oxidative degradation of black liquor were 10 mM H2O2, 1 microL of 10% solution of anionic surfactant (SDS). The importance of the use of surfactants for preparing black liquor for subsequent Fenton's reagent-mediated degradation was discussed.

Fenton's reagent-mediated degradation of residual Kraft black liquor.

In this work, the effect of Fenton's reagent on the degradation of residual Kraft black liquor was investigated. The effect of Fenton's reagent on the black liquor degradation was dependent on the concentration of H2O2. At low concentrations (5 and 15 mM) of H2O2, Fenton's reagent caused the degradation of phenolic groups (6.8 and 44.8%, respectively), the reduction of reaction medium pH (18.2%), and the polymerization of black liquor lignin. At a high concentration (60 mM) of H2O2, Fenton's reagent induced an extensive degradation of lignin (95-100%) and discoloration of the black liquor. In the presence of traces of iron, the addition of H2O2 alone induced mainly lignin fragmentation. In conclusion, Fenton's reagent and H2O2 alone can degrade residual Kraft black liquor under acidic conditions at room temperature.