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1.
Artículo en Inglés | MEDLINE | ID: mdl-38904883

RESUMEN

Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia are considered emerging pathogens classified as a public health problem due to extensive antimicrobial resistance. Therefore, the discovery of new therapeutic strategies has become crucial. This study aimed to evaluate the antimicrobial activity of gallic acid and methyl gallate against non-fermenting bacteria. The study included five clinical isolates of Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia. The minimum inhibitory concentrations of gallic acid and methyl gallate were determined by the broth microdilution method. Growth curves, metabolic activity, and biofilm formation of each bacterial strain in the presence or absence of phenolic compounds were performed. Finally, the therapeutic efficacy of the compounds was evaluated using an in vivo model. Gallic acid and methyl gallate showed antibacterial activity against bacterial strains in a concentration range of 64 to 256 µg/mL, both compounds reduced bacterial growth and metabolic activity of the strains, even at subinhibitory concentrations. Only, methyl gallate exhibited activity to inhibit the formation of bacterial biofilms. Moreover, gallic acid and methyl gallate increased larval survival by up to 60% compared to 30% survival of untreated larvae in a bacterial infection model in Galleria mellonella. Our results highlight the potential of gallic acid and methyl gallate as therapeutic alternatives for infections by emerging non-fermentative bacteria.

2.
Curr Microbiol ; 81(6): 156, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656548

RESUMEN

Aspergillus fumigatus and Fusarium solani infections have become severe health threat; both pathogens are considered a priority due to the increasing emergence of antifungal-resistant strains and high mortality rates. Therefore, the discovery of new therapeutic strategies has become crucial. In this study, we evaluated the antifungal and antivirulence effects of vanillin and tannic acid against Aspergillus fumigatus and Fusarium solani. The minimum inhibitory concentrations of the compounds were determined by the microdilution method in RPMI broth in 96-well microplates according to CLSI. Conidial germination, protease production, biofilm formation, and in vivo therapeutic efficacy assays were performed. The results demonstrated that vanillin and tannic acid had antifungal activity against Aspergillus fumigatus, while tannic acid only exhibited antifungal activity against Fusarium solani. We found that vanillin and tannic acid inhibited conidial germination and secreted protease production and biofilm formation of the fungal pathogens using sub-inhibitory concentrations. Besides, vanillin and tannic acid altered the fungal membrane permeability, and both compounds showed therapeutic effect against aspergillosis and fusariosis in an infection model in Galleria mellonella larvae. Our results highlight the antivirulence effect of vanillin and tannic acid against priority pathogenic fungi as a possible therapeutic alternative for human fungal infections.


Asunto(s)
Antifúngicos , Aspergillus fumigatus , Benzaldehídos , Biopelículas , Fusarium , Pruebas de Sensibilidad Microbiana , Polifenoles , Taninos , Benzaldehídos/farmacología , Fusarium/efectos de los fármacos , Taninos/farmacología , Antifúngicos/farmacología , Biopelículas/efectos de los fármacos , Aspergillus fumigatus/efectos de los fármacos , Animales , Aspergilosis/microbiología , Aspergilosis/tratamiento farmacológico , Virulencia/efectos de los fármacos , Larva/microbiología , Larva/efectos de los fármacos , Fusariosis/tratamiento farmacológico , Fusariosis/microbiología , Esporas Fúngicas/efectos de los fármacos , Mariposas Nocturnas/microbiología , Mariposas Nocturnas/efectos de los fármacos
4.
Mol Biol Rep ; 51(1): 408, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38460043

RESUMEN

BACKGROUND: To describe an oncolytic adenovirus (OAd) encoding SP-SA-E7-4-1BBL that is capable of inducing tumor regression in therapeutic assays. Herein, we tested whether the antitumor effect is given by the induction of a tumor-specific immune response, as well as the minimum dose needed to elicit antitumor protection and monitor the OAd biodistribution over time. METHODS AND RESULTS: C57BL/6 mice (n = 5) per group were immunized twice with OAds encoding SP-SA-E7-4-1BBL, SA-E7-4-1BBL, or SP-SA-4-1BBL and challenged with TC-1 cancer cells. The DNA construct SP-SA-E7-4-1BBL was employed as a control via biolistic or PBS injection. Groups without tumor development at 47 days were rechallenged with TC-1 cells, and follow-up lasted until day 90. The minimum dose of OAd to induce the antitumor effect was established by immunization using serial dilution doses. The cytometry bead assay and the ELISpot assay were used to evaluate cytokine release in response to ex vivo antigenic stimulation. The distribution profile of the OAd vaccine was evaluated in the different organs by histological, immunohistochemical and qPCR analyses. The OAd SP-SA-E7-4-1BBL-immunized mice did not develop tumors even in a rechallenge. A protective antitumor effect was observed from a dose that is one hundredth of most reports of adenoviral vaccines. Immunization with OAd increases Interferon-gamma-producing cells in response to antigen stimulation. OAd was detected in tumors over time, with significant morphological changes, contrary to nontumor tissues. CONCLUSIONS: The OAd SP-SA-E7-4-1BBL vaccine confers a prophylactic, safe, long-lasting, and antigen-dependent antitumor effect mediated by a Th1 antitumor immune response.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Animales , Ratones , Papillomavirus Humano 16 , Ligando 4-1BB/genética , Ligando 4-1BB/farmacología , Distribución Tisular , Ratones Endogámicos C57BL , Adenoviridae/genética , Inmunidad , Neoplasias/terapia
5.
Braz J Microbiol ; 54(3): 1335-1340, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37453029

RESUMEN

Systemic scedosporiosis is a devastating emerging fungal infection caused by several species of the genus Scedosporium in immunocompetent and immunocompromised individuals. In this study, we compared the virulence of different Scedosporium species in a murine model of systemic scedosporiosis by survival assays, fungal burden and histopathological analysis. We found that mice mortality was species-dependent, S. apiospermum, S. aurantiacum and S. dehoogii were the most virulent species. We also observed the dissemination and invasion of Scedosporium species to the brain, spleen and kidney by colony count and histopathological analysis at different times of infection. Particularly, the brain was the tissue most susceptible to invasion during systemic scedosporiosis. This study shows the virulence and pathophysiology of different Scedosporium species and will be useful in facilitating control and prevention strategies for systemic scedosporiosis.


Asunto(s)
Scedosporium , Animales , Ratones , Scedosporium/genética , Antifúngicos/uso terapéutico , Virulencia , Modelos Animales de Enfermedad
6.
Microbes Infect ; 25(6): 105119, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36758890

RESUMEN

Neurocandidiasis is a fungal infection that primarily affects neonates, which is associated with 70% case fatality rates, while pediatric patients who survive infection often have long-term neurological sequelae, making it a clinical requirement to understand the pathogenesis of neonatal neurocandidiasis. Currently, the brain regions to Candida albicans invasion during the neonatal period are not characterized. In this study, 0-day-old mice were infected with C. albicans intravenously to determine dissemination and invasion into the brain at different times post-infection by fungal burden assay and histopathological analysis, additionally cellular death and microglial activation were evaluated by flow cytometry. The results evidenced the dissemination of C. albicans within the first hour of infection in the brain. The meninges were the initial site of invasion during the first 6 hours post infection and then filamentous structures into the brain parenchyma increases during infection, the anatomic regions most susceptible to invasion being the cerebral cortex, thalamus, hypothalamus, midbrain, pons, and medulla oblongata. Furthermore, C. albicans invasion of brain tissue results in cell necrosis and activation of microglia as a consequence of fungal invasion.


Asunto(s)
Candida albicans , Microglía , Humanos , Niño , Ratones , Animales , Necrosis , Encéfalo
7.
Brain Commun ; 4(5): fcac235, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36196088

RESUMEN

Alzheimer's disease is a neurological disorder characterized by the overproduction and aggregation of amyloid-beta and the phosphorylation and intraneuronal accumulation of tau. These events promote synaptic dysfunction and loss, leading to neurodegeneration and cognitive deficits. Astrocytes are intimately associated with synapses and become activated under pathological conditions, becoming neurotoxic and detrimentally affecting synapses. Although it has been established that reducing neuronal tau expression prevents amyloid-beta-induced toxicity, the role of astrocytic tau in this setting remains understudied. Herein, we performed a series of astrocytic and neuronal primary cultures to evaluate the effects of decreasing astrocytic tau levels on astrocyte-mediated amyloid-beta-induced synaptic degeneration. Our results suggest that the downregulation of tau in astrocytes mitigates the loss of synapses triggered by their exposure to amyloid-beta. Additionally, the absence of tau from astrocytes promotes the upregulation of several synaptoprotective genes, followed by increased production of the neuroprotective factor Pentraxin 3. These results expand our understanding of the contribution of astrocytic tau to the neurodegenerative process induced by amyloid-beta-stimulation and how reducing astrocytic tau could improve astrocyte function by stimulating the expression of synaptoprotective factors. Reducing endogenous astrocytic tau expression could be a potential strategy to prevent synaptic damage in Alzheimer's disease and other neurological conditions.

8.
Microb Pathog ; 170: 105718, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35961485

RESUMEN

Scedosporium apiospermum is an opportunistic pathogen that can cause pulmonary infections in both immunosuppressive and immunocompetent patients. Cytokines are molecules that mediate the immune response to promote or eliminate fungal infections. In this work, we evaluated the cytokines profile in the lung and serum of mice infected with Scedosporium apiospermum. We found early production of IL-6, IL-1ß and TNF-α cytokines in the lung of infected mice during the first 5 days of infection. We suggest that release of pro-inflammatory cytokines could play a role in the control of fungal invasion.


Asunto(s)
Micosis , Neumonía , Scedosporium , Animales , Antifúngicos/uso terapéutico , Citocinas , Pulmón , Ratones , Micosis/tratamiento farmacológico , Neumonía/tratamiento farmacológico
9.
Microbes Infect ; 24(6-7): 104984, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35500750

RESUMEN

Neonatal bacteremia remains the major cause of infectious diseases-related death, especially in preterm newborns. Gram-positive bacteria are the main causative agent of neonatal bacteremia and exhibit a high risk of causing pneumonia and/or meningitis. The pathogenesis of bacteremia in preterm newborn is poorly understood. Current neonatal models of bacterial infection have been used to study the disease mechanisms; however, these studies employed mice of several days of age that could be less comparable to the bacteremia in preterm infants. In this study, we infected intravenously 0-day-old BALB/c mice with different inocula of Staphylococcus aureus, Streptococcus agalactiae or Enterococcus faecalis. We found that the mortality of the newborn mice was inoculum-dependent and also bacterial species-dependent. We observed bacterial burden in the lung, liver, brain, kidney and spleen of the infected animals. The lung was the tissue with the greatest bacterial burden and cellular infiltration in animals infected with the three bacteria evaluated. We found increased production of IL-6 and TNFα in the lung from newborn mice at 3 days post-infection. This neonatal model shows bacterial dissemination to the lung and will be useful for promote a better understanding of the pathophysiology of neonatal pneumonia.


Asunto(s)
Bacteriemia , Infecciones Estafilocócicas , Animales , Animales Recién Nacidos , Bacteriemia/microbiología , Bacterias , Bacterias Grampositivas , Humanos , Recién Nacido , Recien Nacido Prematuro , Interleucina-6 , Pulmón , Ratones , Infecciones Estafilocócicas/microbiología , Factor de Necrosis Tumoral alfa
10.
FEMS Yeast Res ; 22(1)2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35488874

RESUMEN

Pichia pastoris has been widely used to produce antigenic proteins aimed to integrate subunit vaccines. Moreover, increasing interest in large-scale vaccine production at the lowest cost is rapidly focusing in the development of yeast surface display (YSD) systems for delivery of antigens. In this scenario, the safety of live yeast administration must be warranted, however, such information is very scarce. Here, we assess the intravenous administration (i.v.) of live P. pastoris cells in order to trace dissemination in BALB/c mice and to evaluate the immune response raised against the yeast compared to the well-defined pathogen Candida albicans. Our results demonstrate dissemination of P. pastoris to the heart, kidney, and spleen, but it is quickly eliminated during the first 48 h postinfection (hpi), with persistence in the liver along with mild mononuclear (MN) and polymorphonuclear (PMN) infiltrate, which was resolved at 144 hpi. In vivo delayed-type hypersensitivity test (DTH) or in vitro antigenic stimulation of mice splenocytes demonstrate that transient infection of P. pastoris did not induce a cell-mediated immune response nor increase the level of circulating IgG or IgM. These results demonstrate the innocuous profile of P. pastoris and support its use as a safe delivery system for vaccine development.


Asunto(s)
Pichia , Saccharomycetales , Administración Intravenosa , Animales , Ratones , Ratones Endogámicos BALB C , Pichia/metabolismo
11.
Microb Pathog ; 161(Pt B): 105285, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34774701

RESUMEN

Candida auris is an emerging multidrug resistant fungal pathogen, which represents a major challenge for newborns systemic infections worldwide. Management of C. auris infections is complicated due to its intrinsic antifungal resistance and the limited information available on its pathogenesis, particularly during neonatal period. In this study, we developed a murine model of C. auris neonatal invasive infection. C. auris dissemination was evaluated by fungal burden and histopathological analysis of lung, brain, liver, kidney, and spleen at different time intervals. We found fungal cells in all the analyzed tissues, neonatal liver and brain were the most susceptible tissues to fungal invasion. This model will help to better understand pathogenesis mechanisms and facilitate strategies for control and prevention of C. auris infections in newborns.


Asunto(s)
Candida , Candidiasis Invasiva , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida auris , Candidiasis Invasiva/tratamiento farmacológico , Farmacorresistencia Fúngica , Ratones , Pruebas de Sensibilidad Microbiana
12.
Microb Pathog ; 158: 105061, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34157411

RESUMEN

Invasive candidiasis is associated with a high incidence and mortality rates in infants, especially in preterm newborns. The immunopathogenesis of the mycosis during the neonatal period is poorly understood. Although several in vivo models exist to study invasive candidiasis, the majority of studies employ distinct routes of infection and use 2 to 6 day-old mice that could be less comparable in studying candidiasis in preterm infants. In this study, by using 0-days-old mice we developed a new neonatal murine model of intravenous Candida albicans infection. Using different inoculums of Candida albicans we evaluated survival, dissemination of the fungus, frequency of CD45+ cells, and cytokine production in the liver, brain, and kidneys of newborn and adult BALB/c mice. Unexpectedly, the newborn mice infected with a low inoculum (1×105 cfu per mouse) of Candida albicans survive to the infection. Compared to adult mice, the liver and brain of newborn animals had the greatest fungal burden, fungal invasion and leukocyte infiltrate. A moderate production of TNFα, IL-1ß, IL-6 and IFNγ was detected in tissues of newborn mice infected with a non-lethal inoculum of Candida albicans. In contrast, overproduction of TNFα, IL-1ß, IL-6 and IL-10 was determined when injecting with a lethal inoculum. In agreement, flow cytometry of brain and liver showed an inoculum-dependent CD45+ leukocyte infiltration in newborn mice infected with Candida albicans. Overall, our data shows that Candida albicans infection in newborn mice affects mainly the brain and liver and a 2-fold increase of the inoculum rapidly becomes lethal probably due to massive fungal invasion and exacerbated CD45+ leukocyte infiltrate and cytokine production. This study is the first analysis of innate immune responses in different tissues during early neonatal disseminated candidiasis.


Asunto(s)
Candidiasis , Inmunidad Innata , Animales , Humanos , Recién Nacido , Ratones , Candida albicans , Candidiasis/inmunología , Recien Nacido Prematuro , Ratones Endogámicos BALB C
13.
Aging Cell ; 19(10): e13233, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32914559

RESUMEN

Cerebral amyloid angiopathy (CAA) is typified by the cerebrovascular deposition of amyloid. The mechanisms underlying the contribution of CAA to neurodegeneration are not currently understood. Although CAA is highly associated with the accumulation of ß-amyloid (Aß), other amyloids are known to associate with the vasculature. Alzheimer's disease (AD) is characterized by parenchymal Aß deposition and intracellular accumulation of tau as neurofibrillary tangles (NFTs), affecting synapses directly, leading to behavioral and physical impairment. CAA increases with age and is present in 70%-97% of individuals with AD. Studies have overwhelmingly focused on the connection between parenchymal amyloid accumulation and synaptotoxicity; thus, the contribution of vascular amyloid is mostly understudied. Here, synaptic alterations induced by vascular amyloid accumulation and their behavioral consequences were characterized using a mouse model of Familial Danish dementia (FDD), a neurodegenerative disease characterized by the accumulation of Danish amyloid (ADan) in the vasculature. The mouse model (Tg-FDD) displays a hyperactive phenotype that potentially arises from impairment in the GABAergic synapses, as determined by electrophysiological analysis. We demonstrated that the disruption of GABAergic synapse organization causes this impairment and provided evidence that GABAergic synapses are impaired in patients with CAA pathology. Understanding the mechanism that CAA contributes to synaptic dysfunction in AD-related dementias is of critical importance for developing future therapeutic interventions.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Angiopatía Amiloide Cerebral/genética , Enfermedades Neurodegenerativas/genética , Animales , Angiopatía Amiloide Cerebral/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Enfermedades Neurodegenerativas/patología
14.
Medisan ; 19(11)nov.. 2015. ilus
Artículo en Español | CUMED | ID: cum-62284

RESUMEN

En el presente artículo se describen los aspectos más significativos de la vida personal y profesional del Dr Ángel Abelardo Arias Lorente, donde se destaca su vocación médica y entrega a su profesión, a través de su accionar activo dentro del marco de la atención a los pacientes. Su dedicación indiscutible a la labor educativa y sus aportes relevantes a la medicina cubana en general y a la urología santiaguera en particular, lo hicieron merecedor de numerosos reconocimientos y condecoraciones(AU)


The most significant aspects in the personal and professional life of Dr Ángel Abelardo Arias Lorente are described in this work, where the medical vocation and devotion to his profession are highlighted, through his active work within the environment of the care to patients. His unquestionable dedication to the educational work and his outstanding contributions to the Cuban medicine in general and to Santiago urology in particular, made him deserve numerous recognitions and metals(AU)


Asunto(s)
Humanos , Masculino , Anciano , Docentes , Médicos , Docentes Médicos , Personajes , Urología
15.
Medisan ; 19(10)oct. 2015. tab
Artículo en Español | CUMED | ID: cum-62260

RESUMEN

Se realizó un estudio descriptivo y transversal de 32 pacientes con priapismo, atendidos en el Servicio de Urología del Hospital Provincial Docente Clinicoquirúrgico Saturnino Lora Torres de Santiago de Cuba, desde enero de 2008 hasta diciembre de 2014, a fin de caracterizarles desde los puntos de vista epidemiológico, diagnóstico y terapéutico. En la serie predominaron el grupo etario de 20-29 años, el color de piel negra y la etiología idiopática como la más frecuente. En 53,1 por ciento de los pacientes no se determinó el tipo de priapismo y 46,9 por ciento de ellos tenían más de 24 horas de evolución antes de recibir asistencia médica. De los que presentaron entre 12-24 horas solo 7,1 por ciento recibió tratamiento quirúrgico. El tratamiento médico fue inefectivo en 76,5 por ciento de los pacientes y 54,9 por ciento de ellos presentó disfunción eréctil(AU)


A descriptive and cross-sectional study of 32 patients with priapism, assisted at the Urology Service of the Saturnino Lora Torres Provincial Teaching Clinical Surgical Hospital in Santiago de Cuba, was carried out from January, 2008 to December, 2014, in order to characterize them from the epidemiological, diagnostic and therapeutical points of view. The 20-29 age group and the black skin color predominated in the series, as well as and the idiopathic etiology as the most frequent one. In the 53.1 percent of the patients priapism type was not determined and 46.9 percent of them had more than 24 hours of clinical course before receiving medical assistance. Of those who arrived between 12-24 hours only 7.1 percent received surgical treatment. The medical treatment was not effective in 76.5 percent of the patients and 54.9 percent of them presented erectile dysfunction(AU)


Asunto(s)
Humanos , Masculino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Priapismo/complicaciones , Priapismo/terapia , Disfunción Eréctil , Erección Peniana , Epidemiología Descriptiva , Estudios Transversales
16.
Medisan ; 19(10)oct.-oct. 2015. tab
Artículo en Español | LILACS, CUMED | ID: lil-762753

RESUMEN

Se realizó un estudio descriptivo y transversal de 32 pacientes con priapismo, atendidos en el Servicio de Urología del Hospital Provincial Docente Clinicoquirúrgico "Saturnino Lora Torres" de Santiago de Cuba, desde enero de 2008 hasta diciembre de 2014, a fin de caracterizarles desde los puntos de vista epidemiológico, diagnóstico y terapéutico. En la serie predominaron el grupo etario de 20-29 años, el color de piel negra y la etiología idiopática como la más frecuente. En 53,1 % de los pacientes no se determinó el tipo de priapismo y 46,9 % de ellos tenían más de 24 horas de evolución antes de recibir asistencia médica. De los que presentaron entre 12-24 horas solo 7,1 % recibió tratamiento quirúrgico. El tratamiento médico fue inefectivo en 76,5 % de los pacientes y 54,9 % de ellos presentó disfunción eréctil.


A descriptive and cross-sectional study of 32 patients with priapism, assisted at the Urology Service of the "Saturnino Lora Torres" Provincial Teaching Clinical Surgical Hospital in Santiago de Cuba, was carried out from January, 2008 to December, 2014, in order to characterize them from the epidemiological, diagnostic and therapeutical points of view. The 20-29 age group and the black skin color predominated in the series, as well as and the idiopathic etiology as the most frequent one. In the 53.1% of the patients priapism type was not determined and 46.9% of them had more than 24 hours of clinical course before receiving medical assistance. Of those who arrived between 12-24 hours only 7.1% received surgical treatment. The medical treatment was not effective in 76.5% of the patients and 54.9% of them presented erectile dysfunction.


Asunto(s)
Priapismo , Urgencias Médicas , Pene , Erección Peniana
17.
Santa Cruz, 2002; .
Tesis en Español | LILACS-Express | LIBOCS, LIBOSP | ID: biblio-1324917
18.
Santa Cruz, 2002; .
Tesis en Español | LILACS-Express | LIBOCS, LIBOSP | ID: biblio-1331324
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