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1.
Prostaglandins Other Lipid Mediat ; 168: 106751, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37295489

RESUMEN

Sphingolipidoses are a group of metabolic diseases in which lysosomal hydrolases dysfunction disrupt normal sphingolipids' metabolism, leading to excess accumulation in cellular compartments and excretion in urine. These pathologies represent a significant burden among Moroccan population, for which an easy access to enzymatic assays and genetic tests is not guaranteed. Parallel analytical methods thus have to be developed for preliminary screening. In this study, 107 patients were addressed to the metabolic platform of the Marrakesh Faculty of Medicine for diagnosis confirmation. Thin-Layer Chromatography was used as a first step to perform chemical profiling of the patients' urinary lipids, allowing 36% of the patients to be efficiently oriented towards the adequate enzymatic assay. UPLC-MS/MS analyses of urinary sulfatides excreted in urines patient had been used to control the reliability of TLC analysis and to obtain more accurate information related to the sulfatides isoforms. This analytical process combining TLC with UPLC-MS/MS has enabled rapid and appropriate patient management in a reduced time and with reduced resources.


Asunto(s)
Esfingolipidosis , Sulfoglicoesfingolípidos , Humanos , Cromatografía Liquida/métodos , Marruecos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos , Esfingolipidosis/diagnóstico
2.
Sci Total Environ ; 758: 143674, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33248773

RESUMEN

Benzophenone-3 (BP3) is a widely used organic UV filter present in many environmental compartments. One way BP3 is released into the environment is through effluents from wastewater treatment plants (WWTPs). These plants are possible sources for degradation activity and WWTP sludge may potentially degrade BP3. Our goal was to identify any BP3 degrading microorganism(s) in WWTP sludge and to investigate whether the degradation was co-metabolic. Initial WWTP sludge microcosms spiked with BP3 showed 100% degradation after 20 days. Multiple transfers of these microcosms, while maintaining a strong selective pressure for BP3 degradation capabilities, resulted in the dominance of one bacterial strain. This strain was identified as Sphingomonas wittichii BP14P and was subsequently isolated. It was shown to degrade BP3 in a growth dependent manner. Strain BP14P utilized BP3 as the sole energy and carbon source and completely degraded BP3 after 7 days in minimal media. We tested the capability of BP14P to degrade nine other UV filters, but the degradation ability seemed to be restricted to BP3. However, whether this specificity is due to the lack of degradation genes, cellular transport or low bioavailability of the other UV filters remained unclear. The efficient degradation of BP3 by a group of bacteria well known for their potential for xenobiotic degradation is an important step forward for a complete risk assessment of the long-term environmental impact of BP3.


Asunto(s)
Aguas del Alcantarillado , Sphingomonas , Benzofenonas , Biodegradación Ambiental
3.
Int J Cosmet Sci ; 42(6): 596-604, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32767373

RESUMEN

OBJECTIVE: Glycation is a common non-enzymatic reaction between proteins and sugars, resulting in the formation of advanced glycation end products (AGEs) in the human body. As can be seen in diabetic patients, the accumulation of AGEs in the skin has aesthetic consequences (wrinkles, brown spots and yellowish complexion). Therefore, the objective of this work was to find compounds isolated from natural sources that could eliminate the final AGEs accumulated in the skin with ageing. METHODS AND RESULTS: A preliminary screening performed on a bank of microbial extracts and pure compounds showed that 2,5-Diketopiperazines (DKPs), as well as the extract of Sphingobacterium sp (SNB-CN13), reduced the presence of AGEs in fibroblasts by -28% and -23%, respectively. In this article, we present the dereplication approach used to reveal the presence of 26 different DKPs in the crude extract of Sphingobacterium sp. Bioguided fractionation has led to the isolation of 12 of them, whose identity has been confirmed by HRMS and NMR. A green synthesis approach has been developed to synthesize 3 symmetrical DKPs. The biological activity of all DKPs was evaluated by the development of an in vitro test using immunocytochemistry to reveal the presence of AGE carboxymethyl-lysine in human dermal fibroblasts. CONCLUSION: Our work shows for the first time that DKPs decrease the amount of carboxymethyl-lysine AGE in elderly human dermal fibroblasts grown in vitro. Therefore, diketopiperazines can be considered as compounds of interest for dermatological and cosmetic applications with an anti-ageing aim.


OBJECTIF: La glycation est une réaction non enzymatique courante entre les protéines et les sucres, qui entraîne la formation de produits finaux de glycation avancée (AGE) dans le corps humain. Comme on peut le voir chez les patients diabétiques, l'accumulation d'AGE dans la peau a des conséquences esthétiques (rides, taches brunes, teint jaunâtre). Par conséquent, l'objectif de ce travail était de trouver des composés isolés de sources naturelles qui pourraient éliminer les AGE finaux accumulés dans la peau avec le vieillissement. MÉTHODES & RÉSULTATS: Un examen préliminaire effectué sur une banque d'extraits microbiens et de composés purs a montré que les 2,5-dicétopipérazines (DKP), ainsi que l'extrait de Sphingobacterium sp. (SNB-CN13), réduisaient la présence d'AGE dans les fibroblastes de - 28% et - 23% respectivement. Dans cet article, nous présentons l'approche de déréplication utilisée pour révéler la présence de 26 DKP différentes dans l'extrait brut de Sphingobacterium sp. Le fractionnement bioguidé a conduit à l'isolement de 12 d'entre elles, dont l'identité a été confirmée par HRMS et RMN. Une approche de synthèse verte a été développée pour synthétiser 3 DKP symétriques. L'activité biologique de toutes les DKP a été évaluée par le développement d'un test in vitro utilisant l'immunocytochimie pour révéler la présence de carboxyméthyl-lysine AGE dans les fibroblastes dermiques humains. CONCLUSION: Nos travaux montrent pour la première fois que les DKP diminuent la quantité de carboxyméthyl-lysine AGE dans les fibroblastes dermiques humains âgés cultivés in vitro. Par conséquent, les dicétopipérazines peuvent être considérées comme des composés intéressants pour des applications dermatologiques et cosmétiques à visée anti-âge.


Asunto(s)
Factores de Edad , Dicetopiperazinas/farmacología , Productos Finales de Glicación Avanzada/efectos de los fármacos , Piel/efectos de los fármacos , Cromatografía Líquida de Alta Presión/métodos , Dicetopiperazinas/química , Femenino , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Humanos , Persona de Mediana Edad , Piel/citología , Piel/metabolismo , Sphingobacterium/química , Espectrometría de Masas en Tándem/métodos
4.
J Appl Microbiol ; 116(2): 288-94, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24219626

RESUMEN

AIMS: We determined the chemical composition and investigated the antifungal activity of Otacanthus azureus (Linden) Ronse essential oil (EO) against a range of dermatophytes alone or in combination with azole antifungals. METHODS AND RESULTS: Aerial parts of the plant were steam-distilled and the obtained oil was analysed by gas chromatography/mass spectrometry and (1) H-NMR. It was shown to be largely composed of sesquiterpenes, with the main component being ß-copaen-4-α-ol. Using broth microdilution techniques, this oil was found to have remarkable in vitro antifungal activities. Minimum inhibitory concentrations as low as 4 µg ml(-1) were recorded. The analysis of the combined effect of the O. azureus EO with azoles using chequerboard assays revealed a synergism between the EO and ketoconazole, fluconazole or itraconazole against Trichophyton mentagrophytes. Notably, the O. azureus essential oil showed low cytotoxicity to VERO cells. CONCLUSIONS: The O. azureus essential oil alone or in combination with azoles is a promising antifungal agent in the treatment for human dermatomycoses caused by filamentous fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: There is much interest in the study of essential oils for the discovery of new antimicrobial drugs. This study has highlighted the antidermatophytic activity of the O. azureus EO.


Asunto(s)
Antifúngicos/farmacología , Arthrodermataceae/efectos de los fármacos , Azoles/farmacología , Aceites Volátiles/farmacología , Plantaginaceae/química , Animales , Antifúngicos/química , Antifúngicos/toxicidad , Chlorocebus aethiops , Dermatomicosis/tratamiento farmacológico , Sinergismo Farmacológico , Hongos/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Aceites Volátiles/toxicidad , Componentes Aéreos de las Plantas/química , Trichophyton/efectos de los fármacos , Células Vero
5.
J Ethnopharmacol ; 137(1): 875-9, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21771652

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The study of traditional remedies used by the Chayahuita, an ethnic group from the Peruvian Amazonia, has prompted us to investigate in detail the ethanolic extract of Pseudelephantopus spicatus (Juss. ex Aubl.) C.F. Baker, which has demonstrated strong biological activity towards Leishmania amazonensis. Our goal was to discover the active compound of this plant-based remedy. MATERIALS AND METHODS: A bioguided fractionation of the crude extract was undertaken based on the biological activity recorded against Leishmania amazonensis axenic amastigotes in in vitro bioassays. RESULTS: Three strongly to moderately active compounds were isolated: two hirsutinolides (the 8,13-diacetyl-piptocarphol and the 8-acetyl-13-O-ethyl-piptocarphol) and ursolic acid. IC(50) against Leishmania amazonensis axenic amastigotes are respectively 0.2, 0.37 and 0.99 µM (while IC(50) of amphotericin B is 0.41 µM). These compounds have never been isolated from this plant species, and germacranolides have never been identified as potential antileishmanial agents. CONCLUSIONS: The compounds isolated from Pseudelephantopus spicatus account for the antileishmanial activity of the plant, thus giving support to its use by the Chayahuita in Peru.


Asunto(s)
Asteraceae , Lactonas/farmacología , Leishmania/efectos de los fármacos , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Tripanocidas/farmacología , Anfotericina B/farmacología , Asteraceae/química , Fraccionamiento Químico , Relación Dosis-Respuesta a Droga , Humanos , Indígenas Sudamericanos , Concentración 50 Inhibidora , Lactonas/química , Lactonas/aislamiento & purificación , Leishmania/crecimiento & desarrollo , Medicina Tradicional , Perú , Componentes Aéreos de las Plantas , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Triterpenos/farmacología , Tripanocidas/química , Tripanocidas/aislamiento & purificación , Ácido Ursólico
6.
Antimicrob Agents Chemother ; 53(10): 4393-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19667291

RESUMEN

We report the isolation and identification of a new quassinoid named simalikalactone E (SkE), extracted from a widely used Amazonian antimalarial remedy made out of Quassia amara L. (Simaroubaceae) leaves. This new molecule inhibited the growth of Plasmodium falciparum cultured in vitro by 50%, in the concentration range from 24 to 68 nM, independently of the strain sensitivity to chloroquine. We also showed that this compound was able to decrease gametocytemia with a 50% inhibitory concentration sevenfold lower than that of primaquine. SkE was found to be less toxic than simalikalactone D (SkD), another antimalarial quassinoid from Q. amara, and its cytotoxicity on mammalian cells was dependent on the cell line, displaying a good selectivity index when tested on nontumorogenic cells. In vivo, SkE inhibited murine malaria growth of Plasmodium vinckei petteri by 50% at 1 and 0.5 mg/kg of body weight/day, by the oral or intraperitoneal routes, respectively. The contribution of quassinoids as a source of antimalarial molecules needs therefore to be reconsidered.


Asunto(s)
Antimaláricos/farmacología , Plasmodium falciparum/efectos de los fármacos , Cuassinas/farmacología , Simaroubaceae/química , Animales , Antimaláricos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Humanos , Espectroscopía de Resonancia Magnética , Malaria/tratamiento farmacológico , Malaria/parasitología , Estructura Molecular , Cuassinas/química , Células Vero
7.
J Ethnopharmacol ; 126(1): 149-58, 2009 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-19631728

RESUMEN

AIM OF THE STUDY: A knowledge attitude and practice study centred on leishmaniasis and its treatment was performed among the Chayahuita, an Amazonian Peruvian ethnic group living in an endemic area. This study documents traditional Chayahuita plant's use and disease concepts. Also, activity of some medicinal plants used by the Chayahuita is highlighted and discussed. MATERIALS AND METHODS: Ninety-three Chayahuita people were interviewed, following a semi-structured questionnaire focussed on disease knowledge and perception, personal attitude and healing practices. Simultaneously, a collection of plants was performed in different ecotopes, in order to make an extensive inventory of the pharmacopoeia. RESULTS: For the Chayahuita, cutaneous (CL) and muco-cutaneous leishmaniasis (MCL) are considered as diseases of their own, with specific names, aetiologies, mode of transmission. Regarding CL, Chayahuita people consider that the humid characteristic of the skin ulcer is a discriminative fact orienting the diagnostic forTa'ta' (leishmaniasis). Forty-six different species were designated useful against LC and /or MCL (29 species by means of the questionnaire and 27 species when collecting in different ecotopes). Thirty-seven extracts corresponding to 31 species used medicinally were screened in vitro against Leishmania amazonensis axenic amastigotes, assessing their viability by the reduction of tetrazolium salt (MTT). Six species displayed a good activity (10 microg/ml

Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Leishmania/efectos de los fármacos , Leishmaniasis/tratamiento farmacológico , Leishmaniasis/etnología , Medicina Tradicional , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Perú/etnología , Fitoterapia , Plantas Medicinales
8.
J Ethnopharmacol ; 111(1): 40-2, 2007 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-17157466

RESUMEN

In French Guiana, Quassia amara L. (Simaroubaceae) leaf tea is a well-known widely used traditional antimalarial remedy. Impact of the vegetal sampling condition on in vivo and in vitro antimalarial activity was assessed. Traditional infusions were prepared with juvenile or mature leaves, both either fresh or dried. Results showed that growing stage and freshness of vegetal material exert a striking effect on antimalarial activity, both in vitro and in vivo. By far, leaf tea made from fresh juvenile (FJ) Quassia amara leaves was the most active. In vitro, active component (simalikalactone D) concentration correlates biological activities, although unexplained subtle variations were observed. In vivo, tea made with dried juvenile (DJ) leaves displays a peculiar behavior, meaning that some components may help simalikalactone D delivery or may be active in vivo only, therefore enhancing the expected curative effect of the traditional preparation.


Asunto(s)
Antimaláricos/farmacología , Bebidas , Desecación , Malaria/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Plasmodium yoelii , Quassia/crecimiento & desarrollo , Animales , Antimaláricos/química , Antimaláricos/normas , Antimaláricos/uso terapéutico , Cromatografía Líquida de Alta Presión , Guyana Francesa , Malaria/parasitología , Ratones , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/crecimiento & desarrollo , Control de Calidad , Quassia/química , Cuassinas/análisis
9.
J Ethnopharmacol ; 110(2): 318-22, 2007 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-17134861

RESUMEN

In the main markets of Paramaribo (Suriname), many stands offer what is locally called "Bitter-cups", or "Kwasi bita beker", small footed-cups, roughly carved from a whitish wood. The use of these cups is strictly medicinal and it seems to be restricted to Suriname, as they are not found in neighbouring countries (Guyana, French Guiana). The aim of this study was to identify the botanical origin of Bitter-cups still in use in the Saramaka traditional medicine (as information from field people was controversial), and document the ethnopharmacology of this original galenical artefact. Microscopic and high performance liquid chromatography (HPLC) analyses were carried out on Bitter-cup, and anatomical criteria (marginal parenchyma band, size of intervessel and vessel-ray pits, rays width and rays composition, vessels clustering, frequency and size of parenchyma pits) together with HPLC profiles of the macerates showed that the wood cup was similar to Quassia amara L. (Simaroubaceae) wood. Ethnopharmacological investigation indicates that the use of these cups is simply due to the pharmacological properties attributed to "bitters", and is strongly linked to tradition and cultural attitudes. This study also emphasizes the long lasting use of these cups, now restricted to Suriname only, with almost no variation over one century.


Asunto(s)
Etnofarmacología , Medicina Tradicional , Farmacia/instrumentación , Quassia , Madera/análisis , Cromatografía Líquida de Alta Presión , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Ensayo de Materiales , Medicina Tradicional/historia , Microscopía , Suriname
10.
J Ethnopharmacol ; 108(1): 155-7, 2006 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-16730421

RESUMEN

French Guiana (North-East Amazonia) records high malaria incidence rates. The traditional antimalarial remedy most widespread there is a simple tea made out from Quassia amara L. leaves (Simaroubaceae). This herbal tea displays an excellent antimalarial activity both in vitro and in vivo. A known quassinoid, simalikalactone D (SkD), was identified as the active compound, with an IC(50) value of 10nM against FcB1 Plasmodium falciparum chloroquine resistant strain in vitro. Lastly, it inhibits 50% of Plasmodium yoelii yoelii rodent malaria parasite at 3.7 mg/kg/day in vivo by oral route. These findings confirm the traditional use of this herbal tea.


Asunto(s)
Antimaláricos/farmacología , Fitoterapia , Plasmodium falciparum/efectos de los fármacos , Quassia/química , Cuassinas/química , Cuassinas/farmacología , Animales , Antimaláricos/química , Bebidas , Guyana Francesa , Medicina Tradicional , Estructura Molecular , Roedores/parasitología
11.
12.
Org Lett ; 1(4): 637-9, 1999 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-10823192

RESUMEN

[formula: see text] A mild new synthetic procedure has been developed for in situ generation and cyclization of iminyl radicals onto pendant alkenes, followed by functionalization of the resulting carbon radical by one of a variety of trapping reagents. The key process in the method involves production of the iminyl radical via treatment of an aldoxime or ketoxime with readily available 2,6-dimethylbenzenesulfinyl chloride at -50 degrees C to room temperature (Hudson reaction).


Asunto(s)
Iminas/síntesis química , Alquenos/química , Ciclización , Radicales Libres , Iminas/química
13.
J Laparoendosc Adv Surg Tech A ; 7(3): 177-81, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9448130

RESUMEN

We describe the combined use of laparoscopic and endoscopic techniques in a case of acute primary gastric volvulus. Once the diagnosis is confirmed with a water-soluble upper gastrointestinal series, prompt intervention is required. With an atraumatic bowel grasper the stomach is re-oriented with the greater curvature in its normal anatomic position. Two transabdominal wall sutures are placed along the greater curvature to fix it to anterior abdominal wall. Upper endoscopy is then performed. Once confident that the gastric mucosa is viable, a 20F "pull-type" gastrostomy tube is placed endoscopically, guided by the external illumination and probing by the laparoscope. The gastrostomy tube now acts as an anterior anchor for the stomach allowing repositioning of the gastropexy sutures if necessary. Endoscopy confirms the placement of a broad, properly aligned gastropexy. Classically, gastric volvulus has been treated by laparotomy. Both endoscopic and laparoscopic techniques have been individually reported in the treatment of acute and chronic gastric volvulus, however, each has as its limitations. By combining the procedures we were able to better assess both the intra-abdominal and the intraluminal status of the stomach and its position before, during, and after fixation to the anterior abdominal wall. The postoperative stay seen with the combined technique was less than has been reported in patients treated by open surgery or by either the endoscopic or laparoscopic methods alone. The combined laparoscopic and endoscopic approach to acute gastric volvulus provides the benefit of a minimally invasive approach, to a better anterior gastropexy. This procedure should be considered when confronted with patients with acute primary, gastric volvulus.


Asunto(s)
Endoscopía/métodos , Vólvulo Gástrico/cirugía , Enfermedad Aguda , Anciano , Gastrostomía , Humanos , Intubación Gastrointestinal/instrumentación , Laparoscopía/métodos , Masculino , Radiografía , Vólvulo Gástrico/diagnóstico por imagen , Técnicas de Sutura
14.
J Org Chem ; 62(2): 275-286, 1997 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-11671399

RESUMEN

The diastereoselectivity of 5-exo-trigonal cyclizations of 2-(4-penten-1-yl)-1,3-dioxolan-2-yl and 2-(4-penten-1-yl)-1,3-dioxan-2-yl radicals is investigated. When dioxolanes or dioxanes derived from C(2) symmetrically substituted diols are employed the diastereoselectivity is poor. In the dioxanyl series this is a consequence of the cyclization occurring through a twist-boat conformer. Disymmetrically substituted dioxanyl radicals, derived from the alcohols 21 and 41, are, however, constrained to chairlike conformations and accordingly give rise to highly diastereoselective cyclizations. Conditions are described for the hydrolysis of the resulting spiroacetals and for determination of the ee of the resulting 2-methylcyclopentanones.

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