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1.
Med Chem ; 17(6): 587-600, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-31995016

RESUMO

BACKGROUND: Cervical cancer is a major public health issue worldwide, occurring in the vast majority of cases (85%) in low-income countries. Human papillomavirus (HPV) mainly infects the mucosal epithelium, and a small portion causes over 600,000 cases every year worldwide at various anatomical spots, mainly leading to anogenital and head and neck. INTRODUCTION: The E6 oncoprotein encoded by cancer-associated alpha HPV can transform epithelial cells into tumorigenic tissue. Therapy for this infection and blocking of the HPV E6 oncoprotein could be provided with cost-effective and abundant natural products which are an exponentially growing topic in the literature. Finding an active natural compound that readily blocks HPV E6 oncoprotein which could be available for developing countries without expensive extraction processes or costly synthetic pathways is of major interest. METHODS: Molecular dynamics simulation was performed using the most up-to-date AMBER protein force field ff14SB and a GPU enabled high performance computing cluster. RESULTS: In this research, we present a study of the binding properties between 10 selected natural compounds that are readily available with two variants of the E6 oncoprotein types (HPV-16 and HPV-18) using 10+ microsecond molecular dynamics simulations. CONCLUSION: Our results suggest that crocetin, ergosterol peroxide and κ-carrageenan natural products bind strongly to both HPV-16 and HPV-18 and could potentially serve as a scaffolding for further drug development.


Assuntos
Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Proteínas de Ligação a DNA/metabolismo , Simulação de Dinâmica Molecular , Proteínas Oncogênicas Virais/metabolismo , Proteínas Repressoras/metabolismo , Proteínas de Ligação a DNA/química , Proteínas Oncogênicas Virais/química , Ligação Proteica , Conformação Proteica , Proteínas Repressoras/química , Risco
2.
Rev. esp. investig. quir ; 22(3): 93-95, 2019. ilus
Artigo em Espanhol | IBECS | ID: ibc-186037

RESUMO

La mayoría de los pacientes con divertículos de colon no presentan complicaciones y, en caso de presentarlas, suelen ser intraabdominales. Exponemos el caso de un varón de 52 años que consultó en el Servicio de Urgencias por dolor abdominal de 3 semanas de evolución asociado a tumoración infraumbilical con signos de flogosis. La analítica sanguínea mostró leucocitosis importante con desviación izquierda y elevación de la proteína C reactiva. La tomografía computarizada evidenció un gran absceso de pared abdominal que comunicaba con cambios inflamatorios en sigma ("en reloj de arena"). Se decidió intervenir de forma quirúrgica urgente hallando diverticulitis aguda de sigma muy evolucionada. Se realizó drenaje y colostomía en cañón de escopeta sobre varilla. El absceso de pared abdominal como debut de diverticulitis aguda complicada es una forma de presentación muy infrecuente de esta patología, existiendo pocos antecedentes descritos en la literatura al respecto


The majority of patients with diverticula have not any complications. If they appear, they use to present as an intra-abdominal complication. We present the case of a 52-year-old man who came to the Emergency Service with lower abdominal pain for 3 weeks and a visible mass with inflammatory signs in this site. The blood test showed a marked leucocytosis with neutrophilia and the compute tomography revealed an abscess of the abdominal wall related with inflammatory changes in sigmoid colon ("hourglass"). We decided emergency surgery and we found evolved acute sigmoid diverticulitis. Local drainage of the abscess and loop colostomy opened over a rod were performed. The abdominal wall abscess as a form of debut of acute complicated diverticulitis is a very uncommon presentation of this pathology. There are few antecedents in the literature about this matter


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Abscesso Abdominal/etiologia , Abscesso Abdominal/cirurgia , Doença Diverticular do Colo/complicações , Doença Diverticular do Colo/cirurgia , Tomografia Computadorizada por Raios X , Abscesso Abdominal/diagnóstico por imagem , Doença Aguda
3.
J Phys Chem B ; 122(30): 7514-7521, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-29986138

RESUMO

Acute, or chronic, ethanol consumption leads to the formation of free radicals in the liver, which is related to hepatic damage. Among these radicals 1-hydroxyethyl, •CH(OH)CH3, is the most abundant one. Thus, efficient •CH(OH)CH3 scavengers are likely candidates to offer liver protection after ethanol consumption. In the present work ergosterol and homogentisic acid (HGA), which are found in edible mushrooms, were investigated as potential candidates to that purpose. The investigation was carried out following the QM-ORSA protocol, and using the density functional theory (DFT). The overall rate constants calculated for the •CH(OH)CH3 radical scavenging activity of ergosterol in lipid and ethanol media are 1.34 × 107 and 1.86 × 107 M-1 s-1, respectively. For homogentisic acid the overall rate constant in lipid, ethanol and aqueous media are 4.33 × 108, 2.74 × 106, and 3.62 × 107 M-1 s-1, respectively. Accordingly, both compounds are predicted to efficiently scavenge the •CH(OH)CH3 radical. Thus, the results from this investigation support the antioxidant capability of edible mushrooms, their potential beneficial effects against ethanol hepatotoxicity, and the nutraceuticals properties of ergosterol and homogentisic acid.


Assuntos
Ergosterol/química , Etanol/química , Sequestradores de Radicais Livres/química , Ácido Homogentísico/química , Radical Hidroxila/química , Agaricales/química , Agaricales/metabolismo , Teoria Quântica , Termodinâmica
4.
Rev. argent. microbiol ; 50(1): 90-96, mar. 2018. graf, tab
Artigo em Espanhol | LILACS | ID: biblio-958034

RESUMO

El género Fusarium es ampliamente conocido por su capacidad fitopatógena, típicamente asociada al marchitamiento vascular. Sin embargo, se ha reportado como un patógeno oportunista en pacientes inmunocompetentes e inmunocomprometidos, por lo que puede ser considerado como un microorganismo de interés en estudios de patogenicidad en diferentes hospederos. Este trabajo evaluó la capacidad patogénica de aislamientos de Fusarium spp. de diferentes orígenes en hospederos vegetales y en un hospedero animal (modelo murino). Doce aislamientos de Fusarium spp. de origen vegetal, animal superficial, humano superficial y humano sistémico fueron inoculados en plantas de tomate, gulupa y clavel, y en ratones BALB/c, inmunocompetentes e inmunosuprimidos. Las pruebas de patogenicidad en plantas no mostraron todos los síntomas asociados al marchitamiento vascular en los tres modelos vegetales, pero la colonización y la necrosis de los haces vasculares observada en todos los casos, independientemente de la especie de Fusarium y el origen del aislamiento, demostró el potencial infeccioso de Fusarium spp. en las diferentes especies de plantas. Por otro lado, las pruebas de patogenicidad en el modelo murino evidenciaron alteraciones del comportamiento. Asimismo, se observó en el modelo murino que todos los aislamientos infectaron y colonizaron diferentes órganos, independientemente de su origen, de la especie o del estado inmunitario del hospedero, pero solamente cinco (de diferente origen y correspondientes a diferentes especies) generaron mortalidad. En contraste, la prueba de inoculación superficial no evidenció lesiones ni colonización. Los resultados observados indican el potencial papel patogénico de los aislamientos de Fusarium spp. en los diferentes tipos de hospederos. Sin embargo, es necesario profundizar en estudios de factores de patogenicidad que expliquen la capacidad de este género para colonizar múltiples hospederos.


The genus Fusarium is widely recognized for its phytopathogenic capacity. However, it has been reported as an opportunistic pathogen in immunocompetent and immunocompromised patients. Thus, it can be considered a microorganism of interest in pathogenicity studies on different hosts. Therefore, this work evaluated the pathogenicity of Fusarium spp. isolates from different origins in plants and animals (murine hosts). Twelve isolates of Fusarium spp. from plants, animal superficial mycoses, and human superficial and systemic mycoses were inoculated in tomato, passion fruit and carnation plants, and in immunocompetent and immunosuppressed BALB/c mice. Pathogenicity tests in plants did not show all the symptoms associated with vascular wilt in the three plant models; however, colonization and necrosis of the vascular bundles, regardless of the species and origin of the isolates, showed the infective potential of Fusarium spp. in different plant species. Moreover, the pathogenicity tests in the murine model revealed behavioral changes. It was noteworthy that only five isolates (different origin and species) caused mortality. Additionally, it was observed that all isolates infected and colonized different organs, regardless of the species and origin of the isolates or host immune status. In contrast, the superficial inoculation test showed no evidence of epidermal injury or colonization. The observed results in plant and murine models suggest the pathogenic potential of Fusarium spp. isolates in different types of hosts. However, further studies on pathogenicity are needed to confirm the multihost capacity of this genus.


Assuntos
Animais , Humanos , Camundongos , Fusariose , Fusarium , Doenças das Plantas/microbiologia , Virulência , Modelos Animais de Doenças , Fusarium/patogenicidade , Camundongos Endogâmicos BALB C
5.
Rev Argent Microbiol ; 50(1): 90-96, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-28988902

RESUMO

The genus Fusarium is widely recognized for its phytopathogenic capacity. However, it has been reported as an opportunistic pathogen in immunocompetent and immunocompromised patients. Thus, it can be considered a microorganism of interest in pathogenicity studies on different hosts. Therefore, this work evaluated the pathogenicity of Fusarium spp. isolates from different origins in plants and animals (murine hosts). Twelve isolates of Fusarium spp. from plants, animal superficial mycoses, and human superficial and systemic mycoses were inoculated in tomato, passion fruit and carnation plants, and in immunocompetent and immunosuppressed BALB/c mice. Pathogenicity tests in plants did not show all the symptoms associated with vascular wilt in the three plant models; however, colonization and necrosis of the vascular bundles, regardless of the species and origin of the isolates, showed the infective potential of Fusarium spp. in different plant species. Moreover, the pathogenicity tests in the murine model revealed behavioral changes. It was noteworthy that only five isolates (different origin and species) caused mortality. Additionally, it was observed that all isolates infected and colonized different organs, regardless of the species and origin of the isolates or host immune status. In contrast, the superficial inoculation test showed no evidence of epidermal injury or colonization. The observed results in plant and murine models suggest the pathogenic potential of Fusarium spp. isolates in different types of hosts. However, further studies on pathogenicity are needed to confirm the multihost capacity of this genus.


Assuntos
Fusariose , Fusarium , Animais , Modelos Animais de Doenças , Fusarium/patogenicidade , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Doenças das Plantas/microbiologia , Virulência
6.
J Phys Chem A ; 120(31): 6103-10, 2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27428932

RESUMO

The photosensitizer ability of phenalenone was studied in aqueous and lipid media through the single electron transfer reactions, employing the density functional theory. Although phenalenone is a well-known photosensitizer and is widely used as an (1)O2 reference sensitizer, little is known about the reaction mechanism involved. In this study we carried out a single electron transfer reaction between the basal, excited, oxidized and reduced state of phenalenone with oxygen molecules such as (3)O2 and O2(•-). In aqueous media the photosensitizer capacity of phenalenone was measured through both type I and type II mechanisms. In lipid media the photosensitizer ability of phenalenone was attributed to the type II mechanism. The results indicated that the photosensitizer ability of phenalenone shows a heavy reliance on the media where the reaction occurs whether this is an aqueous or lipid media. Finally, this study supports the idea about that electron transfer reactions can be used to study the photosensitizer ability of molecules.


Assuntos
Fenalenos/química , Fármacos Fotossensibilizantes/química , Piperazinas/química , Teoria Quântica , Transporte de Elétrons , Radicais Livres/química , Cinética , Estrutura Molecular , Oxigênio/química , Termodinâmica , Água/química
7.
Rev. esp. investig. quir ; 19(1): 25-27, 2016. ilus
Artigo em Espanhol | IBECS | ID: ibc-150959

RESUMO

Introducción: La osteítis del pubis es un cuadro inflamatorio raro y autolimitado, no infeccioso y relativamente benigno de la sínfisis del pubis. Se presenta normalmente como consecuencia de un trauma -quirúrgico o no - sobre el pubis o la zona inguinal. La manifestación clínica más constante es el dolor suprapúbico irradiado a la región inguinal. Es fundamental realizar un diagnóstico diferencial con la osteomielitis, aunque ambas se pueden dar de forma concomitante en la misma persona. Reporte de caso: describimos y explicamos el manejo de un paciente que desarrolló una osteomielitis del pubis tras una cirugía abdominal en la que se colocó una malla de refuerzo. Al no existir mejoría de la clínica con el tratamiento antibiótico, fue necesario una nueva cirugía para retirar la malla y realizar curetaje de la sínfisis del pubis. La osteomielitis es una complicación rara tras una cirugía abdominal, si bien, debe de existir la sospecha de la misma en los casos en los que aparezca dolor a nivel de la sínfisis del pubis asociado o no a fiebre y alteraciones analíticas


Osteitis pubis is defined as an idiopathic, inflammatory, self-limited disease of the pubic symphysis and surrounding structures. Osteitis pubis most commonly occurs among athletes but can also occur among non-athletes as a result of any pelvic stress (eg, trauma, pelvic surgery, pregnancy). Suprapubic pain irradiating to the inguinal region makes the clinical diagnosis difficult, since the symptom is shared among a wide variety of diseases including osteomyelitis. Osteitis and osteomyelitis can be found concomitantly in a single patient. Case report : we describe and explain the management of a patient who developed pubic osteomyelitis after an abdominal surgery in which a reinforcing mesh is placed. In the absence of clinical improvement with antibiotic treatment , further surgery was necessary to remove the mesh and perform curettage of the symphysis pubis. Osteomyelitis is a rare complication after abdominal surgery, and we must think on it in cases where appears pain at the symphysis pubis with or without fever and laboratory abnormalities


Assuntos
Humanos , Feminino , Adulto , Osteíte/complicações , Osteíte/diagnóstico , Osteíte/patologia , Osso Púbico , Hérnia Inguinal/diagnóstico , Hérnia Inguinal/patologia , Hérnia Inguinal/terapia , Osteomielite/complicações , Osteomielite/patologia , Osteomielite/terapia , Diagnóstico Precoce
8.
J Pineal Res ; 58(1): 107-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25424557

RESUMO

The copper sequestering ability of melatonin and its metabolites cyclic 3-hydroxymelatonin (3OHM), N(1) -acetyl-N(2) -formyl-5-methoxykynuramine (AFMK), and N(1) -acetyl-5-methoxykynuramine (AMK) was investigated within the frame of the Density Functional Theory. It was demonstrated that these compounds are capable of chelating copper ions, yielding stable complexes. The most likely chelation sites were identified. Two different mechanisms were modeled, the direct-chelation mechanism (DCM) and the coupled-deprotonation-chelation mechanism (CDCM). It is proposed that, under physiological conditions, CDCM would be the main chelation route for Cu(II). It was found that melatonin and its metabolites fully inhibited the oxidative stress induced by Cu(II)-ascorbate mixtures, via Cu(II) chelation. In the same way, melatonin, AFMK, and 3OHM also prevented the first step of the Haber-Weiss reaction, consequently turning off the ˙OH production via the Fenton reaction. Therefore, it is proposed that, in addition to the previously reported free radical scavenging cascade, melatonin is also involved in a concurrent 'chelating cascade', thereby contributing to a reduction in oxidative stress. 3OHM was identified as the most efficient of the studied compounds for that purpose, supporting the important role of this metabolite in the beneficial effects of melatonin against oxidative stress.


Assuntos
Quelantes/química , Cobre/química , Melatonina/química , Modelos Químicos , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Ascórbico/química , Ácido Ascórbico/farmacologia , Quelantes/farmacologia , Cobre/metabolismo , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos
9.
Phys Chem Chem Phys ; 16(3): 1197-207, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24292723

RESUMO

The study of the ˙OOH, ˙OOCH3 and ˙OOCHCH2 radicals scavenging processes by esculetin (ES) was carried out in aqueous and lipid media, using the density functional theory. Three reaction mechanisms were considered: single electron transfer (SET), hydrogen transfer (HT) and radical adduct formation (RAF). Rate constants and branching ratios for the different paths are reported. It was found that in lipid media the main mechanism of reaction is HT, while in aqueous solution it depends on the predominant acid-base form of esculetin. HT was found to be the main mechanism involved in the free radical scavenging activity of neutral esculetin (H2ES), while for anionic esculetin (HES(-)) the relative importance of the different mechanisms changes with the reacting radical. Based on the calculated rate constants, it is proposed that esculetin has moderate peroxyl scavenging activity in lipid media while in aqueous solution, at physiological pH, it is excellent for that purpose. In addition, the possible regeneration of ES, after scavenging the first radical, was investigated in aqueous solution, at physiological pH. It was found that regeneration is very likely to occur, which suggests that this compound has the ability to scavenge several radical equivalents (two per cycle), under such conditions.

10.
Phys Chem Chem Phys ; 15(31): 13137-46, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23824251

RESUMO

In this work, we have carried out a quantum chemistry and computational kinetics study on the reactivity of propyl gallate towards ˙OOH, ˙OOCH3 and ˙OOCHCH2 radicals, in aqueous and lipid media. We have considered three reaction mechanisms: hydrogen transfer (HT), radical adduct formation (RAF) and single electron transfer (SET). Rate constants and relative branching ratios for the different paths contributing to the overall reaction, at 298.15 K, are reported. Our results show that propyl gallate reacts mainly through the HT mechanism, independently of the solvent or the peroxyl radical, contrary to other phenols such as catechols and guayacols previously studied, which react mainly via the SET mechanism. In aqueous media at physiological pH, the calculated rate constants towards the ˙OOH, ˙OOCH3 and ˙OOCHCH2 radicals are 4.56 × 10(8), 1.59 × 10(6) and 4.05 × 10(8) M(-1) s(-1), while in lipid media the rate constants are 2.94 × 10(4), 7.73 × 10(3) and 9.94 × 10(5) M(-1) s(-1). Thus, a propyl gallate molecule acts as a very efficient peroxyl radical scavenger, both in aqueous and lipid media. Since the gallate moiety is a part of other naturally occurring polyphenols such as aflavine gallates and epigallocatechin gallates, the results of this study could be extrapolated to these compounds. Even if these compounds have other antioxidant structures or enhancers, the activity of the gallate moiety could be considered as a lower limit to their antioxidant activity.


Assuntos
Antioxidantes/química , Galato de Propila/química , Teoria Quântica , Concentração de Íons de Hidrogênio , Cinética , Estrutura Molecular , Água/química
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