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1.
J Cell Biochem ; 125(4): e30540, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38372191

RESUMEN

Breast cancer is the most common cancer in women. Although chemotherapy is still broadly used in its treatment, adverse effects remain a challenge. In this scenario, aptamers emerge as a promising alternative for theranostic applications. Studies using breast cancer cell lines provide useful information in laboratory and preclinical investigations, most of which use cell lines established from metastatic sites. However, these cell lines correspond to cell populations of the late stage of tumor progression. On the other hand, studies using breast cancer cells established from primary sites make it possible to search for new theranostic approaches in the early stages of the disease. Therefore, this work aimed to select RNA aptamers internalized by MGSO-3 cells, a human breast cancer cell line, derived from a primary site previously established in our laboratory. Using the Cell-Internalization SELEX method, we have selected two candidate aptamers (ApBC1 and ApBC2). We evaluated their internalization efficiencies, specificities, cellular localization by Reverse Transcription-qPCR (RT-qPCR) and confocal microscopy assays. The results suggest that both aptamers were efficiently internalized by human breast cancer cells, MACL-1, MDA-MB-231, and especially by MGSO-3 cells. Furthermore, both aptamers could effectively distinguish human breast cancer cells derived from normal human mammary cell (MCF 10A) and prostate cancer cell (PC3) lines. Therefore, ApBC1 and ApBC2 could be promising candidate molecules for theranostic applications, even in the early stages of tumor progression.


Asunto(s)
Aptámeros de Nucleótidos , Neoplasias de la Mama , Humanos , Femenino , Aptámeros de Nucleótidos/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/tratamiento farmacológico , Células MCF-7 , Línea Celular Tumoral , Técnica SELEX de Producción de Aptámeros
2.
Food Microbiol ; 119: 104450, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38225051

RESUMEN

From a selection of seven traditional and 14 innovative alheiras, 491 lactic acid bacteria (LAB) were isolated and tested for their antimicrobial activity against several food-borne pathogens. Among these, six strains revealed antimicrobial activity through potential bacteriocin production against 14 Listeria monocytogenes strains, Enterococcus faecalis ATCC 29212, Clostridium sporogenes ESB050, and Clostridium perfringens ESB054. Through whole genome sequencing (WGS), these strains were identified as Lactiplantibacillus plantarum (2), Leuconostoc mesenteroides (1), and Pediococcus acidilactici (3). Furthermore, several orthologues of class II bacteriocins genes were identified, including Plantaricin E, Plantaricin F, Pediocin PA, Enterocin X, Leucocin A, and Coagulin A. No virulence or antibiotic resistance genes' orthologues were detected by WGS analysis. However, the selected LAB strains showed variable phenotypic patterns related to virulence genes and antibiotic resistance when assessed through classical methodologies. None of these strains demonstrated the production of biogenic amines, gelatinase or DNase. Additionally, no hemolytic activity or lipase enzyme production was observed. However, only Lpb. plantarum 9A3 was sensitive to all tested antibiotics and was thus chosen for further examination. The bacteriocins produced by Lpb. plantarum (9A3) exhibited stability across a broad range of conditions, including temperatures from 4 to 100 °C, pH values ranging from 2 to 8, exposure to surfactants and detergents (Tween 20 and 80, SDS, EDTA 0.1, 2 and 5 mM, urea and sodium deoxycholate), and enzymes (papain and catalase). Their maximum activity (AU/mL = 12,800) against four L. monocytogenes strains was observed between 21 and 36 h of growth of Lbp. plantarum 9A3, indicating a bacteriostatic mode of action. Therefore, this strain appears to be a robust candidate for potential application as a protective strain to be used in the food industry. Not only is it safe, but it also produces stable bacteriocins (harbouring genes encoding for the production of three) effectively inhibiting significant pathogens such as L. monocytogenes and C. perfringens.


Asunto(s)
Bacteriocinas , Lactobacillales , Listeria monocytogenes , Bacteriocinas/farmacología , Antibacterianos/farmacología , Pediocinas , Listeria monocytogenes/genética
3.
An Acad Bras Cienc ; 96(2): e20231337, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38922281

RESUMEN

Disorders of gastrointestinal motility are the major physiologic problem in chagasic megacolon. The contraction mechanism is complex and controlled by different cell types such as enteric neurons, smooth muscle, telocytes, and an important pacemaker of the intestine, the interstitial cells of Cajal (ICCs). The role of ICCs in the progression of acute and chronic Chagas disease remains unclear. In the present work, we investigate the aspects of ICCs in a long-term model of Chagas disease that mimics the pathological aspects of human megacolon. Different subsets of ICCs isolated from Auerbach's myenteric plexuses and muscle layers of control and Trypanosoma cruzi infected animals were determined by analysis of CD117, CD44, and CD34 expression by flow cytometer. Compared with the respective controls, the results showed a reduced frequency of mature ICCs in the acute phase and three months after infection. These results demonstrate for the first time the phenotypic distribution of ICCs associated with functional dysfunction in a murine model of chagasic megacolon. This murine model proved valuable for studying the profile of ICCs as an integrative system in the gut and as a platform for understanding the mechanism of chagasic megacolon development.


Asunto(s)
Enfermedad de Chagas , Modelos Animales de Enfermedad , Células Intersticiales de Cajal , Megacolon , Animales , Células Intersticiales de Cajal/patología , Enfermedad de Chagas/patología , Enfermedad de Chagas/fisiopatología , Megacolon/parasitología , Megacolon/patología , Megacolon/fisiopatología , Ratones , Citometría de Flujo , Masculino , Trypanosoma cruzi/fisiología
4.
Rev Med Suisse ; 20(856-7): 42-46, 2024 Jan 17.
Artículo en Francés | MEDLINE | ID: mdl-38231098

RESUMEN

2023 has been marked by numerous advancements in the fields of hepatology, liver transplantation, gastroenterology, and interventional endoscopy. These developments hold the promise of changing our daily practice while enhancing the diagnosis and treatment of various hepatic and gastroenterological conditions. Additionally, the European Association for the Study of the Liver (EASL) has issued recommendations for the management of hepatitis delta, acute-on-chronic liver failure, liver diseases of pregnancy, and intrahepatic cholangiocarcinoma. Risankizumab was approved by Swiss Authorities for patients with Crohn's disease and dupilumab was approved for patients with eosinophilic esophagitis. The European Society of Gastrointestinal Endoscopy (ESGE) has revised its recommendations regarding Barrett's esophagus.


2023 a été marquée par de nombreuses avancées dans le domaine de l'hépatologie, de la transplantation hépatique, de la gastroentérologie et de l'endoscopie interventionnelle. Ces développements promettent de changer notre pratique quotidienne dans le but d'améliorer le diagnostic et le traitement de nombreuses affections hépatiques et gastroentérologiques. En outre, la Société européenne d'hépatologie (EASL) a émis des recommandations pour la prise en charge de l'hépatite delta, de l'insuffisance hépatique aiguë sur chronique, des complications hépatiques de la grossesse et du cholangiocarcinome intrahépatique. Le risankizumab a été approuvé par Swissmedic pour le traitement de la maladie de Crohn et le dupilumab pour les patients avec œsophagite à éosinophiles. La Société européenne d'endoscopie a mis à jour ses recommandations concernant l'œsophage de Barrett.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Neoplasias de los Conductos Biliares , Gastroenterología , Femenino , Embarazo , Humanos , Conductos Biliares Intrahepáticos
5.
Hepatology ; 75(4): 968-982, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34662439

RESUMEN

BACKGROUND AND AIMS: Lipoprotein Z (LP-Z) is an abnormal free cholesterol (FC)-enriched LDL-like particle discovered from patients with cholestatic liver disease. This study aims to define the diagnostic value of LP-Z in alcohol-associated hepatitis (AH) and interrogate the biology behind its formation. APPROACH AND RESULTS: We measured serum levels of LP-Z using nuclear magnetic resonance spectroscopy, a well-established clinical assay. Serum levels of LP-Z were significantly elevated in four AH cohorts compared with control groups, including heavy drinkers and patients with cirrhosis. We defined a Z-index, calculated by the ratio of LP-Z to total apolipoprotein B-containing lipoproteins, representing the degree of deviation from normal VLDL metabolism. A high Z-index was associated with 90-day mortality independent from the Model for End-Stage Liver Disease (MELD) and provided added prognosticative value. Both a Z-index ≤ 0.6 and a decline of Z-index by ≥0.1 in 2 weeks predicted 90-day survival. RNA-sequencing analyses of liver tissues demonstrated an inverse association in the expression of enzymes responsible for the extrahepatic conversion of VLDL to LDL and AH disease severity, which was further confirmed by the measurement of serum enzyme activity. To evaluate whether the FC in LP-Z could contribute to the pathogenesis of AH, we found significantly altered FC levels in liver explant of patients with AH. Furthermore, FC in reconstituted LP-Z particles caused direct toxicity to human hepatocytes in a concentration-dependent manner, supporting a pathogenic role of FC in LP-Z. CONCLUSIONS: Impaired lipoprotein metabolism in AH leads to the accumulation of LP-Z in the circulation, which is hepatotoxic from excessive FC. A Z-index ≤ 0.6 predicts 90-day survival independent from conventional biomarkers for disease prognostication.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Hepatitis Alcohólica , Apolipoproteínas B , Colesterol , Humanos , Lipoproteína(a) , Lipoproteínas , Índice de Severidad de la Enfermedad
6.
Appl Microbiol Biotechnol ; 107(5-6): 1687-1696, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36763118

RESUMEN

The enzymatic machinery involved in the biosynthesis of lantibiotic is an untapped source of proteases with different specificities. Lanthipeptide biosynthesis requires proteolysis of specific target sequences by known proteases, which are encoded by contiguous genes. Herein, the activity of lichenicidin A2 (LicA2) trimming proteases (LicP and LicT) was investigated in vivo. Firstly, the impact of some residues and the size of the peptide were evaluated. Then followed trials in which LicA2 leader was evaluated as a tag to direct production and secretion of other relevant peptides. Our results show that a negatively charged residue (preferably Glu) at cleavage site is important for LicP efficacy. Some mutations of the lichenicidin hexapeptide such as Val-4Ala, Asp-5Ala, Asn-6Ser, and the alteration of GG-motif to GA resulted in higher processing rates, indicating the possibility of improved lichenicidin production in Escherichia coli. More importantly, insulin A, amylin (non-lanthipeptides), and epidermin were produced and secreted to E. coli supernatant, when fused to the LicA2 leader peptide. This work aids in clarifying the activity of lantibiotic-related transporters and proteases and to evaluate their possible application in industrial processes of relevant compounds, taking advantage of the potential of microorganisms as biofactories. KEY POINTS: • LicM2 correct activity implies a negatively charged residue at position -1. • Hexapeptide mutations can increase the amount of fully processed Bliß. • LicA2 leader peptide directs LicTP cleavage and secretion of other peptides.


Asunto(s)
Bacteriocinas , Péptido Hidrolasas , Péptido Hidrolasas/metabolismo , Escherichia coli/genética , Péptidos , Señales de Clasificación de Proteína , Endopeptidasas
7.
Dermatol Online J ; 29(3)2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37591271

RESUMEN

Spiny keratoderma (SKD) is a rare palmoplantar keratoderma that presents with few to numerous millimetric hyperkeratotic projections on the palms and soles. It has been described with both hereditary and acquired variants. The acquired form, which presents in older adults, has been associated with a variety of systemic diseases and malignant conditions. In patients suspected of having acquired spiny keratoderma, an evaluation for malignant conditions may be warranted. Treatment with topical keratolytics or topical and oral retinoids is usually insufficient. Herein, we present the case of a 58-year-old man diagnosed with idiopathic SKD.


Asunto(s)
Queratodermia Palmoplantar , Masculino , Humanos , Anciano , Persona de Mediana Edad , Queratodermia Palmoplantar/diagnóstico , Retinoides , Síndrome
8.
Am J Gastroenterol ; 117(3): 453-461, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35041626

RESUMEN

INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) is closely associated with an increased risk of cardiovascular disease. We aimed to determine whether the fibrosis-4 index (FIB-4) can identify patients with NAFLD at highest risk of cardiovascular events. METHODS: We analyzed data from 81,108 patients with (i) a diagnosis of NAFLD, (ii) nonalcoholic steatohepatitis (NASH), or (iii) at risk (RISK) of NASH. The outcome of interest was major adverse cardiovascular events (MACE) defined by myocardial infarction, hospitalization for unstable angina or heart failure, and coronary revascularization. RESULTS: The mean age was 62 years, and 49.6% were men. Among 67,273 patients without previous cardiovascular disease, 9,112 (13.5%) experienced MACE over median follow-up of 3 years. In univariate analysis, a FIB-4 ≥2.67 was a significant predictor of MACE overall (hazard ratio [HR] 1.82, 95% confidence interval [CI] 1.63-2.04, P < 0.001) and across all baseline groups. After adjusting for established cardiovascular risk factors, FIB-4 ≥2.67 remained the strongest predictor of MACE overall (adjusted HR [aHR] 1.80, 95% CI 1.61-2.02, P < 0.001) and was consistently associated with myocardial infarction (aHR 1.46, 95% CI 1.25-1.70, P < 0.001), hospitalization for unstable angina (aHR 1.24, 95% CI 1.03-1.49, P = 0.025), hospitalization for heart failure (aHR 2.09, 95% CI 1.86-2.35, P < 0.001), coronary artery bypass graft (aHR 1.65, 95% CI 1.26-2.17, P < 0.001), and percutaneous coronary intervention (aHR 1.72, 95% CI 1.21-2.45, P = 0.003). DISCUSSION: In a large, real-world cohort of patients with NAFLD, NASH, or at RISK of NASH, the FIB-4 score was the strongest independent predictor of MACE, beyond established cardiovascular risk factors and baseline liver diagnosis.


Asunto(s)
Insuficiencia Cardíaca , Infarto del Miocardio , Enfermedad del Hígado Graso no Alcohólico , Angina Inestable/complicaciones , Angina Inestable/epidemiología , Femenino , Insuficiencia Cardíaca/epidemiología , Humanos , Cirrosis Hepática/complicaciones , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/epidemiología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Factores de Riesgo
9.
Int J Mol Sci ; 23(18)2022 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-36142897

RESUMEN

The intestinal epithelium is a principal site for environmental agents' detection. Several inflammation- and stress-related signalling pathways have been identified as key players in these processes. However, it is still unclear how the chronic intake of inadequate nutrients triggers inflammatory signalling pathways in different intestinal regions. We aimed to evaluate the impact of unhealthy dietary patterns, starting at a younger age, and the association with metabolic dysfunction, intestinal inflammatory response, and obesity in adulthood. A rat model was used to evaluate the effects of the consumption of sugary beverages (HSD) and a Western diet (WD), composed of ultra-processed foods. Both diets showed a positive correlation with adiposity index, but a positive correlation was found between the HSD diet and the levels of blood glucose and triglycerides, whereas the WD diet correlated positively with triglyceride levels. Moreover, a distinct inflammatory response was associated with either the WD or HSD diets. The WD induced an increase in TLR2, TLR4, and nuclear factor-kappa B (NF-κB) intestinal gene expression, with higher levels in the colon and overexpression of the inducible nitric oxide synthase. In turn, the HSD diet induced activation of the TLR2-mediated NF-κB signalling pathway in the small intestine. Altogether, these findings support the concept that early intake of unhealthy foods and nutrients are a main exogenous signal for disturbances of intestinal immune mechanisms and in a region-specific manner, ultimately leading to obesity-related disorders in later life.


Asunto(s)
FN-kappa B , Receptor Toll-Like 4 , Animales , Glucemia , Dieta Occidental , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Obesidad , Ratas , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Triglicéridos
10.
Palliat Support Care ; : 1-6, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35818713

RESUMEN

BACKGROUND: This study is aimed to perform the translation and cultural adaptation of the Neonatal Palliative Care Attitude Scale (NiPCAS) and evaluation of its psychometric properties with Portuguese neonatal nurses. METHODS: The research started with a scoping review that allowed the identification of the NiPCAS. It was a methodological study with a quantitative approach. The semantic equivalence of the items was adjusted with the participation of 20 neonatal nurse experts. They performed facial and quantitative content validation. Psychometric validation of the NiPCAS was performed on a nonprobability nurses sample (n = 283) in 13 level 3 neonatal units between July 2021 and February 2022. Confirmatory factor analysis using the polychoric correlation matrix was performed to estimate factor validity using the "lavaan" package for R statistical software. Internal consistency was estimated using Cronbach's alpha coefficient, and item sensitivity was assessed using the asymmetry and kurtosis coefficients. Empirical indices were considered: chi-square over degrees of freedom; comparative fit index; normed fit index; Tucker-Lewis index, and root mean square error of approximation; average extracted variance and composite reliability were used to assess convergent validity. RESULTS: Asymmetry and kurtosis were <|3| and <|7|, respectively, suggesting psychometric sensitivity. The convergent validity of the factors was: F1, FCF1 = 0.90 and for F2, FCF2 = 0.80, and a lower value for F3, FCF3 = 0.40. According to the squared correlation criterion average variance extracted (AVE) between the factors, there was no discriminant validity for F1 and F2, but there was discriminant validity for F1, F3, F2, and F3. SIGNIFICANCE OF RESULTS: This instrument has implications for providing end-of-life care to newborns and their families. The use of this instrument reveals several barriers and facilitating elements inherent in the organization and culture of the facility and nursing education.

11.
World J Microbiol Biotechnol ; 38(1): 18, 2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-34977979

RESUMEN

Lantibiotics are a promising class of natural antimicrobial peptides. Lichenicidin is a two-peptide lantibiotic in which two mature peptides act synergistically to exhibit full bioactivity. Considering the two-peptide lantibiotics described so far, only cytolysin has been deeply characterized in terms of toxicity towards eukaryotic cells and it was found to be hemolytic and cytotoxic. This work aimed to improve the production of lichenicidin in vivo and characterize its antibacterial activity and toxicity against human cells. Peptides were purified and minimal inhibitory concentration (MIC) was determined against several strains; a time-kill assay was performed with Staphylococcus aureus. The hemolytic effect of lichenicidin was evaluated on blood samples from healthy donors and its toxicity towards human fibroblasts. The quantity of purified peptides was 1 mg/l Bliα and 0.4 mg/l Bliß. MIC for methicillin-sensitive and resistant S. aureus (MSSA and MRSA) strains were 16-32 µg/ml and 64-128 µg/ml, respectively. At the MIC, lichenicidin took less than 3 h to eliminate MSSA, indicating a strong bactericidal effect. It induces cell lysis at the highest concentration, an effect that might be potentiated by Bliß. Lichenicidin was not cytotoxic to human erythrocytes and fibroblasts. In this work, we evaluated the therapeutic potential of lichenicidin as a possible antimicrobial alternative.


Asunto(s)
Antiinfecciosos/farmacología , Péptidos Antimicrobianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Bacteriocinas/farmacología , Fibroblastos/efectos de los fármacos , Péptidos/farmacología , Secuencia de Aminoácidos , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Péptidos Antimicrobianos/aislamiento & purificación , Bacteriocinas/química , Bacteriocinas/aislamiento & purificación , Línea Celular , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Hemólisis , Humanos , Pruebas de Sensibilidad Microbiana
12.
Cell Biochem Funct ; 39(3): 442-454, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33389760

RESUMEN

Human adipose-derived stromal/stem cells (ASC) have immunomodulatory properties and the potential to differentiate into several cell lines, important for application in regenerative medicine. However, the contamination with dermal fibroblasts (FIB) can impair the beneficial effects of ASC in cell therapy. It is then essential to develop new strategies that contribute to the distinction between these two cell types. In this study, we performed functional assays, high-throughput RNA sequencing (RNA-Seq) and quantitative PCR (qPCR) to find new markers that can distinguish ASC and FIB. We showed that ASC have adipogenic and osteogenic differentiation capacity and alkaline phosphatase activity, not observed in FIB. Gene expression variation analysis identified more than 2000 differentially expressed genes (DEG) between these two cell types. We validated 16 genes present in the list of DEG, including the alkaline phosphatase gene (ALPL). In conclusion, we showed that ASC and FIB have distinct biological properties as demonstrated by alkaline phosphatase activity and differentiation capacity, besides having different gene expression profiles. SIGNIFICANCE OF THE STUDY: Although many differences between stromal stem cells derived from human adipose tissue (ASC) and human dermal fibroblasts (FIB) are described, it is still difficult to find specific markers to differentiate them. This problem can interfere with the therapeutic use of ASC. This work aimed to find new markers to differentiate these two cell populations. Our findings suggest that these cells can be distinguished by biological and molecular characteristics, such as adipogenic and osteogenic differentiation, alkaline phosphatase activity and differential gene expression profiles. The DEG were related to the regulation of the cell cycle, development process, structural organization of the cell and synthesis of the extracellular matrix. This study helps to find new cellular markers to distinguish the two populations and to better understand the properties of these cells, which can improve cell therapy.


Asunto(s)
Tejido Adiposo/metabolismo , Dermis/metabolismo , Fibroblastos/metabolismo , RNA-Seq , Células Madre/metabolismo , Tejido Adiposo/citología , Dermis/citología , Fibroblastos/citología , Humanos , Especificidad de Órganos , Células Madre/citología , Células del Estroma/citología , Células del Estroma/metabolismo
13.
Arch Biochem Biophys ; 663: 83-94, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30586545

RESUMEN

Bacillus licheniformis I89 is a non-pathogenic, Gram-positive bacterium, frequently found in soil. It has several biotechnological applications as producer of valuable compounds such as proteases, amylases, surfactants, and lantibiotics. Herein, it is reported the identification of the polar lipidome of B. licheniformis I89 during the different growth phases (lag, exponential and stationary) at 37 °C. The analytical approach relied on hydrophilic interaction liquid chromatography coupled to electrospray ionization mass spectrometry (HILIC-ESI-MS), accurate mass measurements and tandem mass spectrometry (MS/MS). In the lipidome of B. licheniformis I89 were identified four phospholipid classes: phosphatidylethanolamine, phosphatidylglycerol, lysyl-phosphatidylglycerol, and cardiolipin; two glycolipid classes: monoglycosyldiacylglycerol and diglycosyldiacylglycerol; and two phosphoglyceroglycolipid classes: mono-alanylated lipoteichoic acid primer and lipoteichoic acid primer. The same lipid species were identified at the different growth phases, but there were significant differences on the relative abundance of some molecular species. There was a significant increase in the 30:0 lipid species and a significant decrease in the 32:0 lipid species, between exponential and stationary phases, when compared to lag phase. No differences were observed between exponential and stationary phases. The lipidomic-based approach used herein is a very promising tool to be employed in the study of bacterial lipid composition, which is a requirement to understand its metabolism and response to growth conditions.


Asunto(s)
Bacillus licheniformis/metabolismo , Cromatografía Liquida/métodos , Metabolismo de los Lípidos , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Bacillus licheniformis/crecimiento & desarrollo , Interacciones Hidrofóbicas e Hidrofílicas , Fosfolípidos/metabolismo
14.
Biotechnol Bioeng ; 116(11): 3053-3062, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31350903

RESUMEN

Lantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial peptides that arise as an alternative to the traditional antibiotics. Lichenicidin is active against clinically relevant bacteria and it was the first lantibiotic to be fully produced in vivo in the Gram-negative host Escherichia coli. Here, we present the results of a library of lichenicidin mutants, in which the mutations were generated based on the extensive bibliographical search available for other lantibiotics. The antibacterial activity of two-peptide lantibiotics, as is lichenicidin, requires the synergistic activity of two peptides. We established a method that allows screening for bioactivity which does not require the purification of the complementary peptide. It is an inexpensive, fast and user-friendly method that can be scaled up to screen large libraries of bioengineered two-peptide lantibiotics. The applied system is reliable and robust because, in general, the results obtained corroborate structure-activity relationship studies carried out for other lantibiotics.


Asunto(s)
Bacteriocinas , Escherichia coli , Mutagénesis Sitio-Dirigida , Biblioteca de Péptidos , Bacteriocinas/biosíntesis , Bacteriocinas/genética , Escherichia coli/genética , Escherichia coli/metabolismo
15.
Food Microbiol ; 77: 202-207, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30297051

RESUMEN

Acinetobacter baumanni is recognized as one of the most important agents of nosocomial infections. Other species such as Acinetobacter lwoffii have also been associated with such infections. These species can be found in food products, such as vegetables, fruits and meats which can be a source of transmission of these organisms to community and hospital settings. Evidence that hospitals' kitchens are a route of entry of pathogenic and antimicrobial-resistant bacteria was recently demonstrated. This study aimed to determine whether different Acinetobacter spp. isolated from human and food samples (lettuce, turkey meat, apple and pear) were resistant to stress conditions often applied in food processes, such as exposure to 60 °C, AMUKINA® and vinegar. Also the influence of food matrices on the behavior of isolates to these stress conditions was evaluated. Treatment with AMUKINA® and vinegar were effective against all clinical and food isolates. Exposure to 60 °C resulted in the reduction of the majority of isolates to values below the detection limit of the enumeration technique, however, it is important to note that most of the reductions only occurred after 30 min of exposure. One food isolate identified as A. baumanni was resistant to this thermal treatment and one clinical isolate only decreased 4 log cycles after 1 h. In general, food isolates were demonstrated to be more resistant than clinical isolates and no significant differences (p > 0.05) were found between A. baumanni and A. lwoffii species. With the exception of one food isolate that was more resistant to thermal stress in the presence of turkey meat, the food matrices investigated did not confer protection to the applied stresses. Due to the limited knowledge on this topic, we believe that this study is an important contribution to understanding the behavior of Acinetobacter spp. when exposed to treatments commonly applied to foods.


Asunto(s)
Acinetobacter/crecimiento & desarrollo , Acinetobacter/aislamiento & purificación , Microbiología de Alimentos , Estrés Fisiológico , Ácido Acético/farmacología , Acinetobacter/efectos de los fármacos , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/crecimiento & desarrollo , Acinetobacter baumannii/aislamiento & purificación , Desinfectantes/farmacología , Manipulación de Alimentos , Hospitales , Calor , Humanos , Lactuca/microbiología , Límite de Detección , Malus/microbiología , Carne/microbiología , Pruebas de Sensibilidad Microbiana , Portugal , Pyrus/microbiología , Factores de Tiempo
16.
Rev Med Suisse ; 14(616): 1489-1494, 2018 Aug 29.
Artículo en Francés | MEDLINE | ID: mdl-30156781

RESUMEN

Primary biliary cholangitis (PBC) is an autoimmune liver disease which affects primarily women and is characterized by progressive destruction of small intrahepatic bile ducts. Most common symptoms are fatigue and pruritus. Diagnostic hallmarks are cholestasis and positive antimitochondrial antibodies. The first-line therapy is ursodeoxycholic acid (UDCA), with excellent results when started at an early stage. Nevertheless, 30­40 % of patients do not achieve a complete biochemical response with UDCA. In these cases, the adjunction of obeticholic acid can be discussed. Fibrates appear to be a promising alternative. Liver transplantation yields excellent outcomes in advanced cases.


La cholangite biliaire primitive (CBP) est une hépatopathie chronique auto-immune, caractérisée par une destruction progressive des voies biliaires intrahépatiques de petit calibre qui affecte majoritairement les femmes. La CBP se manifeste principalement par une fatigue ainsi qu'un prurit et se traduit au premier plan par une cholestase. L'élément clé du diagnostic est la présence d'autoanticorps antimitochondries. Le traitement de choix est l'acide ursodésoxycholique (AUDC). Il est primordial de le débuter à un stade précoce de la maladie. Néanmoins, 30­40 % des patients ne répondent pas à l'AUDC. L'acide obéticholique peut être envisagé dans cette situation. Les fibrates ont montré des résultats encourageants. Au stade avancé de la maladie, la transplantation hépatique est la seule intervention curative, avec d'excellents résultats.


Asunto(s)
Colangitis , Cirrosis Hepática Biliar , Trasplante de Hígado , Enfermedades Autoinmunes , Colangitis/cirugía , Femenino , Humanos , Cirrosis Hepática Biliar/cirugía , Ácido Ursodesoxicólico
20.
Drug Metab Rev ; 48(4): 577-592, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27580162

RESUMEN

Tramadol and tapentadol are centrally acting, synthetic opioid analgesics used in the treatment of moderate to severe pain. Main metabolic patterns for these drugs in humans are well characterized. Tramadol is mainly metabolized by cytochrome P450 CYP2D6 to O-desmethyltramadol (M1), its main active metabolite. M1 and tapentadol undergo mainly glucuronidation reactions. On the other hand, the pharmacokinetics of tramadol and tapentadol are dependent on multiple factors, such as the route of administration, genetic variability in pharmacokinetic components and concurrent consumption of other drugs. This review aims to comparatively discuss the metabolomics of tramadol and tapentadol, namely by presenting all their known metabolites. An exhaustive literature search was performed using textual and structural queries for tramadol and tapentadol, and associated known metabolizing enzymes and metabolites. A thorough knowledge about tramadol and tapentadol metabolomics is expected to provide additional insights to better understand the interindividual variability in their pharmacokinetics and dose-responsiveness, and contribute to the establishment of personalized therapeutic approaches, minimizing side effects and optimizing analgesic efficacy.


Asunto(s)
Metabolómica , Fenoles/farmacocinética , Tramadol/farmacocinética , Animales , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Interacciones Farmacológicas , Humanos , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Tapentadol
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