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1.
Parasitol Res ; 123(6): 243, 2024 Jun 14.
Article de Anglais | MEDLINE | ID: mdl-38874599

RÉSUMÉ

Diphyllobothriosis, a fish-borne zoonosis in South America, is mainly caused by the Pacific broad tapeworm Adenocephalus pacificus Nybelin, 1931, a parasite of considerable concern in fishery resources due to its impact on public health. A new diphyllobothrid, Diphyllobothrium sprakeri Hernández-Orts et al. Parasites Vectors 14:219, 2021, was recently described from sea lions from the Pacific Coast, but marine fish acting as intermediate hosts are unknown. The objective of this study was to confirm the presence of plerocercoid larvae of Diphyllobothriidae Lühe, 1910 (Cestoda: Diphyllobothriidea) in nine fish species of commercial importance in Peru. Of a total of 6999 fish (5861 Engraulis ringens, 853 Sciaena deliciosa, 6 Sciaena callaensis, 171 Scomber japonicus, 40 Trachurus murphyi, 40 Ariopsis seemanni, 18 Merluccius peruanus, 5 Sarda chiliensis, and 5 Coryphaena hippurus), 183 were infected with plerocercoid larvae, representing a total prevalence of 2.61% and a mean intensity of 3.2. Based on mtDNA cox1 sequences of 43 plerocercoids, a phylogenetic analysis revealed that 41 belong to A. pacificus and two to D. sprakeri. These findings are first molecular data for D. sprakeri larvae, and the infections of E. ringens and T. murphyi by plerocercoid larvae represent the first records of intermediate/paratenic hosts for this species. Hence, the findings of the current study enhance our understanding of the presence of diphyllobothriid species in commercial fish from the Southeastern Pacific Ocean and their potential impact on seafood safety for local human populations.


Sujet(s)
Maladies des poissons , Poissons , Larve , Animaux , Pérou/épidémiologie , Maladies des poissons/parasitologie , Maladies des poissons/épidémiologie , Poissons/parasitologie , Prévalence , Larve/classification , Larve/croissance et développement , Larve/génétique , Phylogenèse , Infections à cestodes/médecine vétérinaire , Infections à cestodes/parasitologie , Infections à cestodes/épidémiologie , Cestoda/génétique , Cestoda/classification , Cestoda/isolement et purification , Diphyllobothrium/génétique , Diphyllobothrium/classification , Diphyllobothrium/isolement et purification , Bothriocéphalose/épidémiologie , Bothriocéphalose/parasitologie , Bothriocéphalose/médecine vétérinaire , ADN des helminthes/génétique
2.
Animals (Basel) ; 13(4)2023 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-36830531

RÉSUMÉ

This review focuses on proteins and peptides with antimicrobial activity because these biopolymers can be useful in the fight against infectious diseases and to overcome the critical problem of microbial resistance to antibiotics. In fact, snakes show the highest diversification among reptiles, surviving in various environments; their innate immunity is similar to mammals and the response of their plasma to bacteria and fungi has been explored mainly in ecological studies. Snake venoms are a rich source of components that have a variety of biological functions. Among them are proteins like lectins, metalloproteinases, serine proteinases, L-amino acid oxidases, phospholipases type A2, cysteine-rich secretory proteins, as well as many oligopeptides, such as waprins, cardiotoxins, cathelicidins, and ß-defensins. In vitro, these biomolecules were shown to be active against bacteria, fungi, parasites, and viruses that are pathogenic to humans. Not only cathelicidins, but all other proteins and oligopeptides from snake venom have been proteolyzed to provide short antimicrobial peptides, or for use as templates for developing a variety of short unnatural sequences based on their structures. In addition to organizing and discussing an expressive amount of information, this review also describes new ß-defensin sequences of Sistrurus miliarius that can lead to novel peptide-based antimicrobial agents, using a multidisciplinary approach that includes sequence phylogeny.

3.
Animals, v. 13, n. 4, 744, fev. 2023
Article de Anglais | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4809

RÉSUMÉ

This review focuses on proteins and peptides with antimicrobial activity because these biopolymers can be useful in the fight against infectious diseases and to overcome the critical problem of microbial resistance to antibiotics. In fact, snakes show the highest diversification among reptiles, surviving in various environments; their innate immunity is similar to mammals and the response of their plasma to bacteria and fungi has been explored mainly in ecological studies. Snake venoms are a rich source of components that have a variety of biological functions. Among them are proteins like lectins, metalloproteinases, serine proteinases, L-amino acid oxidases, phospholipases type A2, cysteine-rich secretory proteins, as well as many oligopeptides, such as waprins, cardiotoxins, cathelicidins, and β-defensins. In vitro, these biomolecules were shown to be active against bacteria, fungi, parasites, and viruses that are pathogenic to humans. Not only cathelicidins, but all other proteins and oligopeptides from snake venom have been proteolyzed to provide short antimicrobial peptides, or for use as templates for developing a variety of short unnatural sequences based on their structures. In addition to organizing and discussing an expressive amount of information, this review also describes new β-defensin sequences of Sistrurus miliarius that can lead to novel peptide-based antimicrobial agents, using a multidisciplinary approach that includes sequence phylogeny.

4.
Pathogens ; 13(1)2023 Dec 30.
Article de Anglais | MEDLINE | ID: mdl-38251344

RÉSUMÉ

Tuberculosis (TB) of the central nervous system (CNS) is a lethal and incapacitating disease. Several studies have been performed to understand the mechanism of bacterial arrival to CNS, however, it remains unclear. Although the interaction of the host, the pathogen, and the environment trigger the course of the disease, in TB the characteristics of these factors seem to be more relevant in the genesis of the clinical features of each patient. We previously tested three mycobacterial clinical isolates with distinctive genotypes obtained from the cerebrospinal fluid of patients with meningeal TB and showed that these strains disseminated extensively to the brain after intratracheal inoculation and pulmonary infection in BALB/c mice. In this present study, BALB/c mice were infected through the intranasal route. One of these strains reaches the olfactory bulb at the early stage of the infection and infects the brain before the lungs, but the histological study of the nasal mucosa did not show any alteration. This observation suggests that some mycobacteria strains can arrive directly at the brain, apparently toward the olfactory nerve after infecting the nasal mucosa, and guides us to study in more detail during mycobacteria infection the nasal mucosa, the associated connective tissue, and nervous structures of the cribriform plate, which connect the nasal cavity with the olfactory bulb.

5.
Microorganisms ; 10(10)2022 Oct 11.
Article de Anglais | MEDLINE | ID: mdl-36296278

RÉSUMÉ

Mine tailings are produced by mining activities and contain diverse heavy metal ions, which cause environmental problems and have negative impacts on ecosystems. Different microorganisms, including yeasts, play important roles in the absorption and/or adsorption of these heavy metal ions. This work aimed to analyze proteins synthesized by the yeast Yarrowia lipolytica AMJ6 (Yl-AMJ6), isolated from Andean mine tailings in Peru and subjected to stress conditions with common heavy metal ions. Yeast strains were isolated from high Andean water samples impacted by mine tailings from Yanamate (Pasco, Peru). Among all the isolated yeasts, the Yl-AMJ6 strain presented LC50 values of 1.06 mM, 1.42 mM, and 0.49 mM for the Cr+6, Cu+2, and Cd+2 ions, respectively. Proteomic analysis of theYl-AMJ6 strain under heavy metal stress showed that several proteins were up- or downregulated. Biological and functional analysis of these proteins showed that they were involved in the metabolism of proteins, nucleic acids, and carbohydrates; response to oxidative stress and protein folding; ATP synthesis and ion transport; membrane and cell wall; and cell division. The most prominent proteins that presented the greatest changes were related to the oxidative stress response and carbohydrate metabolism, suggesting the existence of a defense mechanism in these yeasts to resist the impact of environmental contamination by heavy metal ions.

6.
Int J Mol Sci ; 23(12)2022 Jun 09.
Article de Anglais | MEDLINE | ID: mdl-35742886

RÉSUMÉ

Central nervous system (CNS) tuberculosis is the most lethal and devastating form among the diseases caused by Mycobacterium tuberculosis. The mechanisms by which M. tuberculosis bacilli enter the CNS are still unclear. However, the BBB and the BCSFB have been proposed as possible routes of access into the brain. We previously reported that certain strains of M. tuberculosis possess an enhanced ability to cause secondary CNS infection in a mouse model of progressive pulmonary tuberculosis. Here, we evaluated the morphostructural and molecular integrity of CNS barriers. For this purpose, we analyzed through transmission electron microscopy the ultrastructure of brain parenchymal microvessels and choroid plexus epithelium from animals infected with two mycobacterial strains. Additionally, we determined the expression of junctional proteins and cytokines by immunological techniques. The results showed that the presence of M. tuberculosis induced disruption of the BCSFB but no disruption of the BBB, and that the severity of such damage was related to the strain used, suggesting that variations in the ability to cause CNS disease among distinct strains of bacteria may also be linked to their capacity to cause direct or indirect disruption of these barriers. Understanding the pathophysiological mechanisms involved in CNS tuberculosis may facilitate the establishment of new biomarkers and therapeutic targets.


Sujet(s)
Maladies du système nerveux central , Méningite tuberculeuse , Animaux , Barrière hémato-encéphalique/métabolisme , Encéphale , Maladies du système nerveux central/métabolisme , Épithélium , Souris
7.
Sensors (Basel) ; 22(7)2022 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-35408360

RÉSUMÉ

(1) Background: As breast cancer studies suggest, a high percentage of breast density (PBD) may be related to breast cancer incidence. Although PBD screening is one of the strongest predictors of breast cancer risk, X-ray-based mammography evaluation is subjective. Therefore, new objective PBD measuring techniques are of interest. A case study analyzing the PBD of thirteen female participants using a bioimpedance-based method, the anomalies tracking circle (ATC), is described in this paper. (2) Methods: In the first stage, the breast bioimpedance of each participant was measured. Then, the participant breast density was determined by applying a mammogram just after the breast bioimpedance measurement stage. In the third stage, the ATC algorithm was applied to the measured bioimpedance data for each participant, and a results analysis was done. (3) Results: An ATC variation according to the breast density was observed from the obtained data, this allowed the use of classification techniques to determine the PBD. (4) Conclusions: The described breast density method is a promising approach that might be applied as an auxiliary tool to the mammography in order to obtain precise and objective results for evaluation of breast density and with that determine potential breast cancer risk.


Sujet(s)
Densité mammaire , Tumeurs du sein , Algorithmes , Région mammaire/imagerie diagnostique , Tumeurs du sein/imagerie diagnostique , Femelle , Humains , Mammographie/méthodes
8.
Micromachines (Basel) ; 13(4)2022 Mar 23.
Article de Anglais | MEDLINE | ID: mdl-35457801

RÉSUMÉ

Impedance measuring acquisition systems focused on breast tumor detection, as well as image processing techniques for 3D imaging, are reviewed in this paper in order to define potential opportunity areas for future research. The description of reported works using electrical impedance tomography (EIT)-based techniques and methodologies for 3D bioimpedance imaging of breast tissues with tumors is presented. The review is based on searching and analyzing related works reported in the most important research databases and is structured according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) parameters and statements. Nineteen papers reporting breast tumor detection and location using EIT were systematically selected and analyzed in this review. Clinical trials in the experimental stage did not produce results in most of analyzed proposals (about 80%), wherein statistical criteria comparison was not possible, such as specificity, sensitivity and predictive values. A 3D representation of bioimpedance is a potential tool for medical applications in malignant breast tumors detection being capable to estimate an ap-proximate the tumor volume and geometric location, in contrast with a tumor area computing capacity, but not the tumor extension depth, in a 2D representation.

9.
Death Stud ; 46(8): 1909-1922, 2022.
Article de Anglais | MEDLINE | ID: mdl-33428556

RÉSUMÉ

This study explores how Mayan people from Guatemala and Swedes view and behave toward death. Using an interpretative phenomenological analysis, 10 participants from each culture were interviewed to elucidate the most relevant and important emerging themes. The Mayan approach to death is based on a collective perspective in which consultations with Elders, ancient traditions, and rituals help provide answer to most existential inquiries surrounding death. In contrast, the Swedish approach is based on an individualistic, rational analysis with a focus on life instead of death, but also showing openness to new perspectives on death.


Sujet(s)
Attitude , Comportement cérémoniel , Sujet âgé , Guatemala , Humains , Suède
10.
Microorganisms, v. 10, 2002, out. 2022
Article de Anglais | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4661

RÉSUMÉ

Mine tailings are produced by mining activities and contain diverse heavy metal ions, which cause environmental problems and have negative impacts on ecosystems. Different microorganisms, including yeasts, play important roles in the absorption and/or adsorption of these heavy metal ions. This work aimed to analyze proteins synthesized by the yeast Yarrowia lipolytica AMJ6 (Yl-AMJ6), isolated from Andean mine tailings in Peru and subjected to stress conditions with common heavy metal ions. Yeast strains were isolated from high Andean water samples impacted by mine tailings from Yanamate (Pasco, Peru). Among all the isolated yeasts, the Yl-AMJ6 strain presented LC50 values of 1.06 mM, 1.42 mM, and 0.49 mM for the Cr+6, Cu+2, and Cd+2 ions, respectively. Proteomic analysis of theYl-AMJ6 strain under heavy metal stress showed that several proteins were up- or downregulated. Biological and functional analysis of these proteins showed that they were involved in the metabolism of proteins, nucleic acids, and carbohydrates; response to oxidative stress and protein folding; ATP synthesis and ion transport; membrane and cell wall; and cell division. The most prominent proteins that presented the greatest changes were related to the oxidative stress response and carbohydrate metabolism, suggesting the existence of a defense mechanism in these yeasts to resist the impact of environmental contamination by heavy metal ions.

11.
An. bras. dermatol ; An. bras. dermatol;96(6): 771-773, Nov.-Dec. 2021. graf
Article de Anglais | LILACS | ID: biblio-1355643

RÉSUMÉ

Abstract Carcinoma of the mammary crease is a very rare variant of breast carcinoma, in which the skin lesions are usually the presenting sign. The authors present the case of an 88-year-old woman with an exophytic plaque in the mammary crease of approximately ten years duration. The histopathological and immunohistochemical studies confirmed the diagnosis of infiltrative breast carcinoma (carcinoma of the mammary crease variant). This case highlights the important role of the dermatologist in the early diagnosis of this rare variant of breast cancer.


Sujet(s)
Humains , Femelle , Sujet âgé de 80 ans ou plus , Tumeurs du sein/diagnostic , Carcinomes , Thorax , Région mammaire
12.
An Bras Dermatol ; 96(6): 771-773, 2021.
Article de Anglais | MEDLINE | ID: mdl-34600788

RÉSUMÉ

Carcinoma of the mammary crease is a very rare variant of breast carcinoma, in which the skin lesions are usually the presenting sign. The authors present the case of an 88-year-old woman with an exophytic plaque in the mammary crease of approximately ten years duration. The histopathological and immunohistochemical studies confirmed the diagnosis of infiltrative breast carcinoma (carcinoma of the mammary crease variant). This case highlights the important role of the dermatologist in the early diagnosis of this rare variant of breast cancer.


Sujet(s)
Tumeurs du sein , Carcinomes , Sujet âgé de 80 ans ou plus , Région mammaire , Tumeurs du sein/diagnostic , Femelle , Humains , Thorax
13.
Rev. colomb. cienc. pecu ; 32(3): 232-244, jul.-set. 2019. tab, graf
Article de Anglais | LILACS | ID: biblio-1042794

RÉSUMÉ

Abstract Background: The aquatic environment is continuously being contaminated with toxic chemical substances from industrial, agricultural and domestic activities. The identification of different biomarkers of such contamination is of great relevance to determine the potential impact of those xenobiotics on the health of organisms. Objectives: To estimate the suitability of different biochemical brain biomarkers from tench in order to evaluate the environmental effect of an exposition to different concentrations of the pesticide carbofuran. Methods: The present study focused on the effect of a long-term exposure (28 days) to different concentrations (50, 100 and 200 μg/L) of the pesticide carbofuran on certain biochemical parameters of tench (Tinca tinca L.). Selected biomarkers for stress monitoring were malondialdehyde (MDA), as index of lipid peroxidation, and reduced glutathione (GSH). Moreover, acetylcholinesterase (AChE) activity was quantified as biomarker of effect on fish nervous system. Results: AChE activity was significantly inhibited in fish exposed to all concentrations of carbofuran after 14 and 21 days of exposure, returning to basal levels after this period with 50 and 100 μg/L. Moreover, significant decreases of MDA levels could be detected after 14 and 21 days of exposure to 200 μg/L, lasting until the end of the experiment. GSH levels decreased after 14 and 21 days of exposure to 100 and 200 μg/L; nevertheless, GSH recovered basal levels at the end of the experiment. Conclusion: All the three biochemical parameters assessed -mainly inhibition of AChE activity- could be adequate biomarkers of early exposition (less than 14 days) to low doses of carbofuran in biomonitoring programs, being MDA reduction also related to longer exposure.


Resumen Antecedentes: El ambiente acuático está continuamente contaminado con sustancias químicas tóxicas provenientes de actividades industriales, agrícolas y domésticas. La identificación de diferentes biomarcadores de dicha contaminación es de gran relevancia para determinar el impacto potencial de esos xenobióticos en la salud de los organismos. Objetivo: Estimar la idoneidad de diferentes biomarcadores cerebrales bioquímicos de tenca para evaluar el efecto ambiental de una exposición a diferentes concentraciones del pesticida carbofurano. Método: El presente estudio se centró en los efectos de una exposición a largo plazo (28 días) a diferentes concentraciones (50, 100 y 200 μg/L) del pesticida carbofurano sobre determinados parámetros bioquímicos de la tenca (Tinca tinca L.). Los biomarcadores seleccionados para el control del estrés fueron el malondialdehído (MDA), como indicador de peroxidación lipídica, y el glutatión reducido (GSH). Además, se cuantificó la actividad acetilcolinesterasa (AChE), como biomarcador de efecto sobre el sistema nervioso del pez. Resultados: La actividad AChE se inhibió significativamente en los peces expuestos a todas las concentraciones de carbofurano después de 14 y 21 días de exposición, regresando a los niveles basales tras este periodo en las exposiciones con 50 y 100 μg/L. Así mismo se detectaron descensos significativos de los niveles de MDA tras 14 y 21 días de exposición con 200 μg/L, manteniéndose hasta el final del experimento. Los niveles de GSH descendieron tras 14 y 21 días de exposición con 100 y 200 µg/l; sin embargo, los niveles basales se recuperaron al final del experimento. Conclusión: Los tres parámetros bioquímicos evaluados, pero principalmente la inhibición de la actividad de AChE, podrían usarse como biomarcadores de exposición temprana (menos de 14 días) a bajas dosis de carbofurano en programas de biomonitorización, estando la reducción de MDA también relacionada con exposiciones más prolongadas.


Resumo Antecedentes: O meio aquático está sendo continuamente contaminado com substâncias químicas tóxicas de atividades industriais, agrícolas e domésticas. A identificação de diferentes biomarcadores de tal contaminação é de grande relevância para determinar o impacto potencial desses xenobióticos na saúde dos organismos. Objetivo: Estimativa da idoneidade de várias biomarcadores cerebrais bioquímicos de tenca para avaliar o efeito ambiental de uma exposição a diferentes concentrações do pesticida carbofurano. Método: O presente estudo centrou-se no efeito de uma exposição a longo prazo (28 dias) a diferentes concentrações (50, 100 e 200 μg/L) do pesticida carbofurano em certos parâmetros bioquímicos da tenca (Tinca tinca L.). Os biomarcadores selecionados para o monitoramento do estresse foram malondialdeído (MDA), como índice de peroxidação lipídica e glutationa reduzida (GSH). Além disso, a atividade da acetilcolinesterase (AChE) foi quantificada, como biomarcador de efeito sobre o sistema nervoso do peixe. Resultados: A atividade de AChE foi significativamente inibida em peixes expostos a todas as concentrações de carbofurano após 14 e 21 dias de exposição, voltando aos níveis basais após esse período com 50 e 100 μg/L. Além disso, as diminuições significativas dos níveis de MDA podem ser detectadas após 14 e 21 dias de exposição a 200 μg/L, até o final do experimento. Os níveis de GSH diminuíram após 14 e 21 dias de exposição a 100 e 200 μg/L, porém GSH recuperou os níveis basais no final do experimento. Conclusão: Todos os três parâmetros bioquímicos avaliados, mas principalmente a inibição da atividade AChE, podem ser biomarcadores adequados de exposição precoce (menos de 14 dias) a baixas doses de carbofurano em programas de biomonitorização, sendo a redução de MDA também relacionada a exposições mais longas.

14.
Front Immunol ; 9: 2291, 2018.
Article de Anglais | MEDLINE | ID: mdl-30337929

RÉSUMÉ

Epstein-Barr virus (EBV) is an oncogenic virus associated with the development of aggressive and poor-prognosis B-cell lymphomas in patients infected with human immunodeficiency virus (HIV+ patients). The most important risk factors for these malignancies include immune dysfunction, chronic immune activation, and loss of T-cell receptor (TCR) repertoire. The combination of all these factors can favor the reactivation of EBV, malignant cell transformation, and clinical progression toward B-cell lymphomas. The overarching aim of this study was to evaluate the frequency, phenotype, functionality, and distribution of TCR clonotypes for EBV-specific T-cell subpopulations in HIV+ patients at different clinical stages and for HIV+ patients with B-cell lymphoma, as well as to establish their association with clinical variables of prognostic value. Factors were studied in 56 HIV+ patients at different clinical stages and in six HIV+ subjects with diagnosed B-cell lymphoma. We found a significant decrease in all subpopulations of EBV-specific CD4+ T cells from HIV+ patients at stage 3 and with B-cell lymphoma. EBV-specific effector CD8+ T cells, particularly effector memory cells, were also reduced in HIV+ patients with B-cell lymphoma. Interestingly, these cells were unable to produce IFN-γ and lacked multifunctionality in HIV+ patients. The TCR-Vß repertoire, which is key for protection against EBV in healthy individuals, was less diverse in HIV+ patients due to a lower frequency of TCR-Vß2+, Vß4+, Vß7.1+, Vß9+, Vß13.6+, Vß14+, Vß17+, Vß22+ CD4+, Vß14+, and Vß17+ CD8+ T cells. HIV+ patients with positive plasma EBV loads (EBV+HIV+) had a noteworthy decrease in the levels of both TNF-α+ and multifunctional TNF-α+/IL-2+ and TNF-α+/IFN-γ+ CD8+ T cells. Altogether, our findings demonstrate that HIV+ patients have significant alterations in the immune response to EBV (poor-quality immunity) that can favor viral reactivation, escalating the risk for developing EBV-associated B-cell lymphomas.


Sujet(s)
Co-infection , Infections à virus Epstein-Barr/immunologie , Infections à VIH/immunologie , Herpèsvirus humain de type 4/immunologie , Interactions hôte-pathogène/immunologie , Récepteur lymphocytaire T antigène, alpha-bêta/métabolisme , Lymphocytes T/immunologie , Lymphocytes T/métabolisme , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Études cas-témoins , Cytokines/métabolisme , Évolution de la maladie , Infections à virus Epstein-Barr/mortalité , Infections à virus Epstein-Barr/virologie , Femelle , Infections à VIH/virologie , Humains , Immunomodulation , Mâle , Adulte d'âge moyen , Pronostic , Jeune adulte
15.
Rev. peru. biol. (Impr.) ; 25(4): 445-452, oct. 2018. ilus, tab
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1094340

RÉSUMÉ

El objetivo de este estudio fue investigar la resistencia al mercurio y los antibióticos, y la transferencia de resistencia al mercurio por plásmidos conjugativos en 55 cepas de Escherichia coli aisladas de aguas superficiales del litoral de Lima, Perú. Se determinó la Concentración Mínima Inhibitoria (CMI) a diversos antibióticos y al mercurio en las cepas aisladas. Para confirmar la resistencia plasmídica al mercurio, se realizó la curación de estos con dodecil sulfato de sodio (SDS) 10%. El ensayo de transferencia de plásmidos por conjugación se realizó usando la cepa receptora E. coli DH5α sólo con las cepas que mostraron sensibilidad al mercurio después de la curación. La extracción de los plásmidos de resistencia fue realizada sólo en las cepas transconjugantes resistentes al mercurio. 41 (74.5%) cepas fueron resistentes al mercurio (HgR), presentando CMIs entre 30 μM (8.25 ppm) y 300 μM (82.5 ppm), de estás, 33 fueron HgR mediante plásmidos y de este último grupo, 14 fueron también resistentes a antibióticos. Sólo 6 cepas poseían plásmidos conjugativos con resistencia al mercurio, mostrando una frecuencia de transconjugación entre 9.41x10-4 y 4.76x10-2%. La alta prevalencia de cepas de E. coli HgR aisladas de la costa limeña podría ser un problema de salud pública y ambiental. En este sentido, los plásmidos congugativos pueden contribuir con la diseminación de mercurio y/o resistencia a antibióticos entre comunidades bacterianas en ambientes marinos.


The Lima coast is highly affected by anthropogenic effluents from wastewater from contaminated urban rivers that flow into the coast. The objective of this study was to investigate the resistance to mercury and antibiotics, and the transfer of resistance to mercury by conjugative plasmids in 55 strains of Escherichia coli isolated of surface seawater from coastal Lima, Peru. The Minimum Inhibitory Concentration (MIC) was determined for various antibiotics and for mercury in the isolated strains. To confirm the plasmid resistance to mercury, the curing was carried out with 10% sodium dodecyl sulfate (SDS). The plasmid transfer assay by conjugation was performed using the E. coli DH5α as recipient strain only with the strains that showed sensitivity to mercury after curing. The extraction of the resistance plasmids was carried out only in the transconjugant strains resistant to mercury. 41 (74.5%) strains were resistant to mercury (HgR), with MICs between 30 μM (8.25 ppm) and 300 μM (82.5 ppm), of these, 33 were HgR by plasmids and of this last group, 14 were also resistant to antibiotics. Only 6 strains had conjugative plasmids with mercury resistance, showing a transconjugation frequency between 9.41x10-4 and 4.76x10-2%. The high prevalence of HgR in E. coli strains isolated from the coast of Lima could be a public and environmental health problem. In this sense, congugative plasmids can contribute to the spread of mercury and/or resistance to antibiotics among bacterial communities in marine environments.

16.
Curr Clin Microbiol Rep ; 5(1): 45-54, 2018 Mar.
Article de Anglais | MEDLINE | ID: mdl-29868332

RÉSUMÉ

PURPOSE OF REVIEW: Trypanosoma cruzi is the causative agent of Chagas disease. Decades after initial infection, ~30% of individuals can develop chronic chagasic cardiomyopathy. There are several proposed mechanisms for pathogenesis of Chagas disease, including parasite persistence, immune responses against parasite or self that continue in the heart, vascular compromise, and involvement of autonomous and central nervous system. Herein, we will focus on the significance of macrophages, mitochondrial dysfunction, and oxidative stress in progression of chagasic cardiomyopathy. RECENT FINDINGS: The current literature suggests that T. cruzi prevents cytotoxic activities of the innate immune cells and persists in the host, contributing to mitochondrial oxidative stress. We discuss how the neoantigens generated due to cellular oxidative damage contribute to chronic inflammatory stress in chagasic disease. SUMMARY: We propose that metabolic regulators, PARP-1/SIRT1, determine the disease outcome by modulating the mitochondrial and macrophage stress and antioxidant/oxidant imbalance, and offer a potential new therapy against chronic Chagas disease.

17.
Front Physiol ; 9: 83, 2018.
Article de Anglais | MEDLINE | ID: mdl-29563877

RÉSUMÉ

Preeclampsia is a maternal hypertensive disorder that affects up to 1 out of 12 pregnancies worldwide. It is characterized by proteinuria, endothelial dysfunction, and elevated levels of the soluble form of the vascular endothelial growth factor receptor-1 (VEGFR-1, known as sFlt-1). sFlt-1 effects are mediated in part by decreasing VEGF signaling. The direct effects of sFlt-1 on cellular metabolism and bioenergetics in preeclampsia, have not been established. The goal of this study was to evaluate whether sFlt-1 causes mitochondrial dysfunction leading to disruption of normal functioning in endothelial and placental cells in preeclampsia. Endothelial cells (ECs) and first-trimester trophoblast (HTR-8/SVneo) were treated with serum from preeclamptic women rich in sFlt-1 or with the recombinant protein. sFlt-1, dose-dependently inhibited ECs respiration and acidification rates indicating a metabolic phenotype switch enhancing glycolytic flux. HTR-8/SVneo displayed a strong basal glycolytic metabolism, remaining less sensitive to sFlt-1-induced mitochondrial impairment. Moreover, results obtained in ECs exposed to serum from preeclamptic subjects demonstrated that increased sFlt-1 leads to metabolic perturbations accountable for mitochondrial dysfunction observed in preeclampsia. sFlt-1 exacerbated mitochondrial reactive oxygen species (ROS) formation and mitochondrial membrane potential dissipation in ECs and trophoblasts exposed to serum from preeclamptic women. Forcing oxidative metabolism by culturing cells in galactose media, further sensitized cells to sFlt-1. This approach let us establish that sFlt-1 targets mitochondrial function in ECs. Effects of sFlt-1 on HTR-8/SVneo cells metabolism were amplified in galactose, demonstrating that sFlt-1 only target cells that rely mainly on oxidative metabolism. Together, our results establish the early metabolic perturbations induced by sFlt-1 and the resulting endothelial and mitochondrial dysfunction in preeclampsia.

18.
PLoS One ; 12(2): e0171191, 2017.
Article de Anglais | MEDLINE | ID: mdl-28192449

RÉSUMÉ

INTRODUCTION: Matrix metalloproteinases and tissue inhibitors of metalloproteinases could be promising biomarkers for establishing prognosis during the development of sepsis. It is necessary to clarify the relationship between matrix metalloproteinases and their tissue inhibitors. We conducted a cohort study with 563 septic patients, in order to elucidate the biological role and significance of these inflammatory biomarkers and their relationship to the severity and mortality of patients with sepsis. MATERIALS AND METHODS: A multicentric prospective cohort was performed. The sample was composed of patients who had sepsis as defined by the International Conference 2001. Serum procalcitonin, creatinine, urea nitrogen, C-Reactive protein, TIMP1, TIMP2, MMP2 and MMP9 were quantified; each patient was followed until death or up to 30 days. A descriptive analysis was performed by calculating the mean and the 95% confidence interval for continuous variables and proportions for categorical variables. A multivariate logistic regression model was constructed by the method of intentional selection of covariates with mortality at 30 days as dependent variable and all the other variables as predictors. RESULTS: Of the 563 patients, 68 patients (12.1%) died within the first 30 days of hospitalization in the ICU. The mean values for TIMP1, TIMP2 and MMP2 were lower in survivors, MMP9 was higher in survivors. Multivariate logistic regression showed that age, SOFA and Charlson scores, along with TIMP1 concentration, were statistically associated with mortality at 30 days of septic patients; serum MMP9 was not statistically associated with mortality of patients, but was a confounder of the TIMP1 variable. CONCLUSION: It could be argued that plasma levels of TIMP1 should be considered as a promising prognostic biomarker in the setting of sepsis. Additionally, this study, like other studies with large numbers of septic patients does not support the predictive value of TIMP1 / MMP9.


Sujet(s)
Service hospitalier d'urgences/statistiques et données numériques , Unités de soins intensifs/statistiques et données numériques , Matrix metalloproteinase 9/sang , Sepsie/sang , Inhibiteur tissulaire de métalloprotéinase-1/sang , Sujet âgé , Azote uréique sanguin , Protéine C-réactive/analyse , Calcitonine/sang , Créatinine/sang , Femelle , Humains , Modèles logistiques , Mâle , Matrix metalloproteinase 2/sang , Adulte d'âge moyen , Analyse multifactorielle , Pronostic , Études prospectives , Sepsie/mortalité , Taux de survie , Inhibiteur tissulaire de métalloprotéinase-2/sang
19.
Trop Anim Health Prod ; 49(1): 145-152, 2017 Jan.
Article de Anglais | MEDLINE | ID: mdl-27718105

RÉSUMÉ

In emergent economies and developing countries of Africa, Asia and Latin America, the major cause for carcass rejection from the international market is bruising; nevertheless, many of these carcases are destined to local markets and meat processing industries for human consumption. Therefore, the aim of the present study was to assess the effect of bruised meat on pH, microbiologic count and biogenic amine (BA) profiles along 21 days of ageing (sampling 1st, 7th, 14th and 21st day) with two packaging method (plastic bag vs vacuum) at 4 °C. A total of 50 bruised carcasses were sampled from 1000 young bulls (Brown Swiss X Zebu) of 18-24 months old and an average live weight of 450 ± 66 kg. The results showed significant differences between packaging systems and bruised vs non-bruised meat. The bruised meat caused higher biogenic amine concentrations than did non-bruised meat. We conclude that bruised meat favoured increments of biogenic amine concentrations, even more than did non-bruised meat. The plastic bag + vacuum system limited the increments of BA concentration during storage time therefore it improved shelf life of meat. These results emphasized the importance of implementing best management practices during pre-slaughter operations of cattle in order to reduce a possible risk factor for bruised meat.


Sujet(s)
Contusions , Qualité alimentaire , Viande rouge/analyse , Viande rouge/microbiologie , Afrique , Amines/composition chimique , Animaux , Poids , Bovins , Microbiologie alimentaire , Sécurité des aliments , Concentration en ions d'hydrogène , Amérique latine , Mâle , Mexique , Température , Vide
20.
Sci Total Environ ; 572: 1059-1065, 2016 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-27522287

RÉSUMÉ

Lepidochelys olivacea is the most abundant and globally distributed sea turtle species in the world and thus, monitoring this species for persistent organic pollutants, such as perfluorinated chemicals, is fundamental for their protection. This study was the first to evaluate the occurrence of five PFCAs (PFOA, PFNA, PFDA, PFUnA, PFDoA) in liver and blood samples of Olive Ridley turtle population from the Escobilla beach (Oaxaca, Mexico). PFDA and PFUnA were the predominant PFCs in blood samples (detected in 93% and 84% of samples, respectively) and were also present in the highest concentrations. Liver samples showed higher PFCA concentrations than whole blood samples, with PFNA and PFDA the most abundant PFCs congeners in liver samples, detected in 65% and 47% of the samples, respectively. The measured levels of contaminants in the blood samples of Lepidochelys olivacea sea turtles were compared to the levels reported in the literature for other turtle species. While linear significant correlations between PFNA, PFDA and PFUnA concentrations in blood samples and curved carapace lengths were determined, no correlation was found for PFOA, supporting the hypothesis that sea turtles could have a higher ability to eliminate this perfluorinated chemical from their blood than other PFCAs. However, we do not know if the concentrations are species or sampling areas dependent.


Sujet(s)
Exposition environnementale , Fluorocarbones/métabolisme , Tortues/métabolisme , Polluants chimiques de l'eau/métabolisme , Animaux , Surveillance de l'environnement , Femelle , Fluorocarbones/sang , Foie/composition chimique , Mexique , Tortues/sang , Polluants chimiques de l'eau/sang
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