Cell accumulation and antileishmanial effect of exogenous and endogenous protoporphyrin IX after photodynamic treatment.

INTRODUCTION: Photodynamic therapy (PDT) using 5-aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) constitutes an interesting alternative for cutaneous leishmaniasis treatment. OBJECTIVE: To evaluate the production of PpIXbased on the administration of ALA and MAL and the effect of ALA-PDTat cellular level on non-infected and infected THP-1 cells using Leishmania ( Viannia ) panamensis or Leishmania ( Leishmania ) infantum (syn Leishmania chagasi ) parasites. MATERIALS AND METHODS: Protoporphyrin IX (PpIX) production and mitochondrial colocalization were evaluated by confocal microscopy. Cell toxicities were evaluated after treatment with the compounds, followed by light irradiation (597-752 nm) at 2.5 J/cm 2 fluency using a colorimetric MTT assay for THP-1 cells and a standard microscopic analysis of parasites. RESULTS were expressed as compound concentration activity against 50% of cells or parasites (CC 50 or IC 50 ). RESULTS: ALA or MAL induced an endogenous PpIX with a red fluorescence localized mainly in the mitochondria inside human cells. ALA and MAL-PDT induced a similar range of toxicities on THP-1 cells (CC 50 0.16 ± 0.01 mM and 0.33 ± 0.019 mM, respectively) without any apparent inhibition of intracellular parasites in the infected cells as compared to untreated controls. Exogenous PpIX-PDT was toxic to THP-1 cells (CC 50 0.00032 ± 0.00002 mM), L. (L.) infantum (IC 50 0.003 ± 0.0001 mM) and L. (V.) panamensis (IC 50 0.024 ± 0.0001 mM) promastigotes. CONCLUSIONS: Despite the effectiveness of exogenous PpIX on promastigotes and the production of PpIX by human infected cells, treatment with ALA or MAL before irradiation was unable to completely destroy L. (L.) infantum or L. (V.) panamensis intracellular amastigotes.

Cell accumulation and antileishmanial effect of exogenous and endogenous protoporphyrin IX after photodynamic treatment / Acumulación celular y efecto anti- Leishmania de la protoporfirina IX exógena y endógena después del tratamiento fotodinámico

Introduction: Photodynamic therapy (PDT) using 5-aminolevulinic acid-induced protoporphyrin IX (ALA-PpIX) constitutes an interesting alternative for cutaneous leishmaniasis treatment. Objective: To evaluate the production of PpIXbased on the administration of ALA and MAL and the effect of ALA-PDTat cellular level on non-infected and infected THP-1 cells using Leishmania ( Viannia ) panamensis or Leishmania ( Leishmania ) infantum (syn Leishmania chagasi ) parasites. Materials and methods: Protoporphyrin IX (PpIX) production and mitochondrial colocalization were evaluated by confocal microscopy. Cell toxicities were evaluated after treatment with the compounds, followed by light irradiation (597-752 nm) at 2.5 J/cm 2 fluency using a colorimetric MTT assay for THP-1 cells and a standard microscopic analysis of parasites. Results were expressed as compound concentration activity against 50% of cells or parasites (CC 50 or IC 50 ). Results: ALA or MAL induced an endogenous PpIX with a red fluorescence localized mainly in the mitochondria inside human cells. ALA and MAL-PDT induced a similar range of toxicities on THP-1 cells (CC 50 0.16±0.01mM and 0.33±0.019 mM, respectively) without any apparent inhibition of intracellular parasites in the infected cells as compared to untreated controls. Exogenous PpIX-PDT was toxic to THP-1 cells (CC 50 0.00032±0.00002 mM), L. (L.) infantum (IC 50 0.003±0.0001 mM) and L. (V.) panamensis (IC 50 0.024±0.0001 mM) promastigotes. Conclusions: Despite the effectiveness of exogenous PpIX on promastigotes and the production of PpIX by human infected cells, treatment with ALA or MAL before irradiation was unable to completely destroy L. (L.) infantum or L. (V.) panamensis intracellular amastigotes.

Introducción. El tratamiento fotodinámico con ácido 5-aminolevulínico como inductor de la protoporfirina IX (ALA-PpIX) constituye una alternativa interesante en el tratamiento de la leishmaniasis cutánea. Objetivo. Evaluar la producción de protoporfirina IX (PpIX) a partir de la administración de ALA o MAL y el efecto de la PDT con ALA a nivel celular en células THP-1 no infectadas e infectadas con Leishmania ( Viannia ) panamensis o Leishmania ( Leishmania ) infantum (syn. Leishmania chagasi ). Materiales y métodos. La producción de protoporfirina IX y su ‘colocalización´ mitocondrial se evaluaron mediante microscopía ‘confocal´. Se evaluó la toxicidad celular después del tratamiento con los compuestos y la aplicación de irradiación de luz (597-752 nm) en una fluencia de 2,5 J/cm 2 mediante el empleo de la prueba colorimétrica con metil-tiazol-tetrazolio (MTT) en las células, y de métodos microscópicos estándar en los parásitos. Los resultados se expresaron como la concentración del compuesto activo en el 50 % de las células o parásitos (CC 50 o CI 50 ). Resultados. El ácido aminolevulínico o el metil-5-aminolevulinato indujeron la protoporfirina IX endógena en células humanas, y se observó fluorescencia de color rojo en las mitocondrias. La actividad del ácido aminolevulínico y del metil-5-aminolevulinato utilizados con terapia fotodinámica fue similar en las células THP-1 (CC 50 0,16±0,01 mM y 0,33±0,019 mM, respectivamente) y, aparentemente, no inhibió los parásitos en las células infectadas, en comparación con los controles. El tratamiento exógeno con protoporfirina IX y terapia fotodinámica fue tóxico para las células THP-1 (CC 50 0,00032 ±0,00002 mM) y para los promastigotes de L. (L .) infantum (IC 50 0,003±0,0001 mM) y L. ( V .) panamensis (CI 50 0,024±0,0001 mM). Conclusiones. A pesar de la ‘fotoactividad´ del tratamiento con protoporfirina IX en promastigotes y de su producción después del tratamiento con ácido aminolevulínico y metil-5-aminolevulinato en las células infectadas con Leishmania , no se observó daño en los amastigotes presentes en las células de L. ( L .) infantum o L . ( V .) panamensis .

[Clinical practice guideline. Traumatic urethral stenosis in males]. / Guía de práctica clínica. La estenosis de uretra postraumática en el hombre.

The incidence of urethral stenosis in Mexico had not been documented. At the Centro Médico Nacional La Raza, during the year 2010, 629 patients with urethral stenosis were attended as outpatient consultation: 85 % with previous urethral stenosis and 15 % with urethral treatment complication. Urethral stenosis is a chronic illness, with multiple etiological origins and the handling is controversial. It has a great negative impact for the patients and the recurrence reaches 85 %. The treatment consisted of an invasive approach (urethral dilations, endoscopy procedure) and open surgery (urethroplasty). The World Health Organization and World Alliance take the world challenge about the urinary tract infections associated with the attention of patients, focused on urethral stenosis. The objective of the following clinical guide is to offer to the health professional a clinical tool for making decisions in the handling of the hardship or masculine urethral stenosis, based on the best available evidence, carrying out in systematized form with bibliographical research using validated terms of the MeSH: urethral structures, in the databases Trip database, PubMed, Guideline Clearinghouse, Cochrane Library and Ovid.

En México no está documentada la incidencia de la estenosis de uretra en forma consistente. En 2010, en el Centro Médico Nacional La Raza se reportaron 629 pacientes en consulta externa, 85 % de uretra anterior y 15 % de uretra posterior. La estenosis uretral es una enfermedad crónica, de etiología variada y manejo controvertido, con gran impacto negativo para los pacientes y recurrencia hasta de 85 %. El tratamiento puede ser instrumentado (dilataciones, cirugía endoscópica) y por cirugía abierta (uretroplastia). La Organización Mundial de la Salud y Alianza Mundial la consideran un reto de la atención de la salud. El objetivo de la siguiente guía es ofrecer al profesional de la salud, una herramienta clínica para la toma de decisiones en la atención de la estenosis uretral masculina, basada en la mejor evidencia identificada mediante la búsqueda bibliográfica sistematizada en las bases de datos Tripdatabase, PubMed, Guideline Clearinghouse, Cochrane Library y Ovid.

Efecto fototoxico de la terapia fotodinamica en promastigotes de leishmania amazonensis / Phototoxic effect of photodynamic therapy in promastigotes of Leishmania amazonensis

Introducción: La terapia fotodinámica utiliza un compuesto fotosensibilizador que en presencia de luz y oxígeno produciendo especies reactivas de oxígeno induciendo la muerte de la célula blanco por apoptosis o necrosis. Estudios in vitro han mostrado que la ftalocianina de aluminio es fototóxica para Leishmania spp. Objetivo:El objetivo de este trabajo fue determinar el efecto del tratamiento con ftalocianina de aluminio clorada en los cambios morfológicos y de la actividad mitocondrial en promastigotes de Leishmania amazonensis. Materiales y métodos: Promastigotes de L amazonensis fueron incubados con ftalocianina de aluminio clorada y posteriormente irradiados con una fluencia de 17 Julios/cm2. De 0, 12 y 24 horas post irradiación los parásitos fueron contados microscópicamente para determinar la inhibición del crecimiento, fueron coloreados con Giemsa para determinar el efecto en los cambios morfológicos y fueron tratados con la sonda fluorescente JC-1 para determinar los cambios en la actividad mitocondrial. Resultados: El tratamiento fotodinámico inhibió el número de promastigotes hasta en un 96,37 %. Se observó reducción del tamaño, fragmentación nuclear y pérdida de núcleo y/o kinetoplasto y pérdida de la actividad mitocondrial. Conclusiones: La terapia fotodinámica es efectiva para la eliminación de promastigotes de L.amazonensis posiblemente por un mecanismo similar a la apoptosis.

Introduction: Photodynamic therapy uses a photosensitizer compound that in presence of light and molecular oxygen is activated producing reactive oxygen species and target cell death by apoptosis or necrosis. In vitro studies have demonstrated the phototoxic effect of aluminium phthalocyanine on Leishmania spp. Objective: The purpose of this study was to determine the effect of chloroaluminum phthalocyanine in the morphological and mitochondrial activity changes of Leishmania amazonensis promastigotes. Materials and methods: Parasites incubated with chloroaluminum phthalocyanine were irradiated with a fluency of 2.5 Julios/cm2. After 0, 12 and 24 hours post irradiation, they were counted microscopically to determine the percentage of inhibition; stained with Giemsa to determine the morphological changes; and treated with the fluorescent probe JC-1 to determine changes in activity mitochondrial. Results: Phothodynamic treatment inhibited the number of promastigotes reaching values of 96.37 %. There was observed downsizing, nuclear fragmentation and loss of nuclear core and / or kinetoplast and loss of mitochondrial activity immediately after irradiation. Conclusions: Photodynamic therapy is effective in eliminating promastigotes of L. amazonensis probably by an apoptosis like mechanism.

Soft purification of N-doped and undoped multi-wall carbon nanotubes.

A soft method for purifying multi-wall carbon nanotubes (N-doped and undoped) is presented. The technique includes a hydrothermal/ultrasonic treatment of the material in conjunction with other subsequent treatments, including the extraction of polyaromatic compounds, dissolution of metal particles, bundle exfoliation, and uniform dispersion. This method avoids harsh oxidation protocols that burn (via thermal treatments) or functionalize (by introducing chemical groups) the nanotubes. We show a careful analysis of each purification step and demonstrate that the technique is extremely efficient when characterizing the materials using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDAX), scanning tuneling electron microscopy (STEM), x-ray powder diffraction (XRD), diffuse reflectance Fourier transform infrared (DRFTIR) spectroscopy and thermogravimetric analysis (TGA).

Trapping, pattern formation, and ordering of polyelectrolyte/single-wall carbon nanotube complexes at the air/water and air/solid interfaces.

The Langmuir and Langmuir-Blodgett (LB) techniques have been applied in a novel approach to build structurally well-ordered, oriented, and organized assemblies of water-soluble single-wall carbon nanotubes (ws-SWCNTs) at the air/water and air/solid interfaces. The SWCNTs were rendered hydrophilic by complexing them with a quenched polyelectrolyte. We observed that the ws-SWCNT concentration at the air/water interface increases with time condensing into different patterns, among which are isolated soap-froths, rings, and the aggregation of cumuli-like 2D-structures. These patterns were recorded at different compression-expansion stages by Brewster angle microscopy (BAM). From the isotherm measurements, we are able to determine the diffusion process by which ws-SWCNT concentration builds up at the water surface. The corresponding LB films were very stable and could be transferred onto mica substrates easily. Atomic force microscopy (AFM) images revealed that the morphology of these films is surface-pressure dependent, and aligned structures with a nematic-like order formed closely packed mono- or multilayer films. The assembly of 2D-nanostructures by means of this approach offers a great potential for emergent technological applications using modified water-soluble SWCNTs.

Photodynamic activity of aluminium (III) and zinc (II) phthalocyanines in Leishmania promastigotes.

INTRODUCTION: Photodynamic therapy is a two-step procedure, involving the use of photosensitizing agents followed by selective illumination of the target lesion with visible light. It produces highly reactive oxygen species and subsequent cellular damage. OBJECTIVE: This study was designed to determine whether Leishmania chagasi and L. panamensis promastigotes were sensitive to photodynamic therapy in vitro. MATERIAL AND METHODS: Leishmania promastigotes were treated with aluminium phthalocyanine chloride and zinc phthalocyanine photosensitizers before illumination with visible light at 670 nm. The parasite photoactivity was calculated by sigmoidal regression analysis. RESULTS: Leishmania chagasi promastigotes were highly photosensitive to aluminium phthalocyanine chloride treatment with effective inhibitory dose50 (ED50) concentration values of 0.0033, 0.0083 and 0.0093 microM upon exposure to 10.0, 5.0, and 2.5 J/cm2 light intensities respectively. By contrast, the activity of aluminium phthalocyanine chloride on L. panamensis was significantly lower (P < 0.01) with ED50 values of 0.17, 0.25, 0.34 microM at the same light intensities. Zinc phthalocyanine activity was significantly (P < 0.01) less active than aluminium phthalocyanine chloride on both strains of these two species and no differences in zinc phthalocyanine activity were found between them. A dose-response phototoxic effect with both phthalocyanines was observed. Parasite inhibition was not observed after aluminium phthalocyanine chloride or zinc phthalocyanine treatment in the dark. The reference drugs hexadecylphosphocholine and amphotericin B were not photoactive. CONCLUSION: Treatment of Leishmania promastigotes with aluminium phthalocyanine chloride and zinc phthalocyanine followed by illumination with visible light at 670 nm inhibited in vitro growth of promastigotes of L. chagasi and L. panamensis. Photodynamic therapy against Leishmania could be a promising strategy for leishmaniasis treatment.