Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Int Microbiol ; 25(3): 481-494, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35106679

RESUMEN

Urinary tract infections (UTIs) are a major concern in public health. The prevalent uropathogenic bacterium in healthcare settings is Escherichia coli. The increasing rate of antibiotic-resistant strains demands studies to understand E. coli pathogenesis to drive the development of new therapeutic approaches. This study compared the gene expression profile of selected target genes in the prototype uropathogenic E. coli (UPEC) strain CFT073 grown in Luria Bertani (LB), artificial urine (AU), and during adhesion to host bladder cells by semi-quantitative real-time PCR (RT-PCR) assays. AU effectively supported the growth of strain CFT073 as well as other E. coli strains with different lifestyles, thereby confirming the appropriateness of this medium for in vitro models. Unexpectedly, gene expression of strain CFT073 in LB and AU was quite similar; conversely, during the adhesion assay, adhesins and porins were upregulated, while key global regulators were downregulated with respect to lab media. Interestingly, fimH and papGII genes were significantly expressed in all tested conditions. Taken together, these results provide for the first time insights of the metabolic and pathogenic profile of strain CFT073 during the essential phase of host cell adhesion.


Asunto(s)
Infecciones por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli Uropatógena , Adhesión Celular , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Humanos , Escherichia coli Uropatógena/genética , Escherichia coli Uropatógena/metabolismo , Virulencia/genética
2.
Int J Vitam Nutr Res ; 91(5-6): 391-395, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33880966

RESUMEN

Urinary tract infections (UTIs) are among the most common causes of infections in women. Via the fecal-perineal-urethral route, uropathogenic Escherichia coli (UPEC) can cause ascending urinary tract infections, including cystitis and pyelonephritis. These infections re-occur within six months or they account for, at least, three episodes within a year of recurrent UTIs (rUTIs). Long term and continuous antibiotic treatment or prophylaxis should be considered as the last options in rUTIs. Conversely, updated European Association of Urology guidelines recommend non-antimicrobial approaches to prevent rUTIs. Accordingly, several studies reported the efficacy of number of natural molecules in inhibiting UPEC adhesion to bladder cells, restraining bacterial growth, as well as stimulating the host innate immune defenses, and protecting the bladder and the kidney mucosa. Therefore, we propose an "anti-UPEC" diet enriched of foods containing natural compounds that were proven effective against UPEC, such as D-mannose, cranberry extracts and medicinal plants. Being a valuable and safe clinical approach to reduce UTI recurrence and limiting the detrimental effects of long and continuous antibiotic prophylaxis, dietary interventions should be evaluated in future clinical trials.


Asunto(s)
Infecciones por Escherichia coli , Infecciones Urinarias , Escherichia coli Uropatógena , Antibacterianos , Infecciones por Escherichia coli/prevención & control , Femenino , Humanos , Vejiga Urinaria , Infecciones Urinarias/prevención & control
3.
Molecules ; 25(2)2020 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-31941080

RESUMEN

Urinary tract infections (UTIs) are mainly caused by uropathogenic Escherichia coli (UPEC). Acute and recurrent UTIs are commonly treated with antibiotics, the efficacy of which is limited by the emergence of antibiotic resistant strains. The natural sugar d-mannose is considered as an alternative to antibiotics due to its ability to mask the bacterial adhesin FimH, thereby preventing its binding to urothelial cells. Despite its extensive use, the possibility that d-mannose exerts "antibiotic-like" activity by altering bacterial growth and metabolism or selecting FimH variants has not been investigated yet. To this aim, main bacterial features of the prototype UPEC strain CFT073 treated with d-mannose were analyzed by standard microbiological methods. FimH functionality was analyzed by yeast agglutination and human bladder cell adhesion assays. Our results indicate that high d-mannose concentrations have no effect on bacterial growth and do not interfere with the activity of different antibiotics. d-mannose ranked as the least preferred carbon source to support bacterial metabolism and growth, in comparison with d-glucose, d-fructose, and l-arabinose. Since small glucose amounts are physiologically detectable in urine, we can conclude that the presence of d-mannose is irrelevant for bacterial metabolism. Moreover, d-mannose removal after long-term exposure did not alter FimH's capacity to bind to mannosylated proteins. Overall, our data indicate that d-mannose is a good alternative in the prevention and treatment of UPEC-related UTIs.


Asunto(s)
Adhesinas de Escherichia coli/metabolismo , Infecciones por Escherichia coli/metabolismo , Proteínas Fimbrias/metabolismo , Manosa/farmacología , Infecciones Urinarias/metabolismo , Escherichia coli Uropatógena/metabolismo , Línea Celular , Humanos , Saccharomyces cerevisiae/metabolismo
4.
BMC Microbiol ; 19(1): 252, 2019 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-31718545

RESUMEN

BACKGROUND: Quantification of intracellular bacteria is fundamental in many areas of cellular and clinical microbiology to study acute and chronic infections. Therefore, rapid, accurate and low-cost methods represent valuable tools in determining bacterial ability to persist and proliferate within eukaryotic cells. RESULTS: Herein, we present the first application of the immunofluorescence In-Cell Western (ICW) assay aimed at quantifying intracellular bacteria in in vitro infection models. The performance of this new approach was evaluated in cell culture infection models using three microorganisms with different lifestyles. Two facultative intracellular bacteria, the fast-growing Shigella flexneri and a persistent strain of Escherichia coli, as well as the obligate intracellular bacterium Chlamydia trachomatis were chosen as bacterial models. The ICW assay was performed in parallel with conventional quantification methods, i.e. colony forming units (CFUs) and inclusion forming units (IFUs). The fluorescence signal intensity values from the ICW assay were highly correlated to CFU/IFUs counting and showed coefficients of determination (R2), ranging from 0,92 to 0,99. CONCLUSIONS: The ICW assay offers several advantages including sensitivity, reproducibility, high speed, operator-independent data acquisition and overtime stability of fluorescence signals. All these features, together with the simplicity in performance, make this assay particularly suitable for high-throughput screening and diagnostic approaches.


Asunto(s)
Infecciones Bacterianas/diagnóstico , Técnicas Bacteriológicas/métodos , Chlamydia trachomatis/crecimiento & desarrollo , Escherichia coli/crecimiento & desarrollo , Shigella flexneri/crecimiento & desarrollo , Línea Celular , Chlamydia trachomatis/aislamiento & purificación , Recuento de Colonia Microbiana , Escherichia coli/aislamiento & purificación , Células HeLa , Ensayos Analíticos de Alto Rendimiento , Humanos , Modelos Biológicos , Reproducibilidad de los Resultados , Shigella flexneri/aislamiento & purificación
5.
Int J Mol Sci ; 20(14)2019 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-31337077

RESUMEN

Carbapenem-resistant Acinetobacter baumannii strains cause life-threatening infections due to the lack of therapeutic options. Although the main mechanisms underlying antibiotic-resistance have been extensively studied, the general response to maintain bacterial viability under antibiotic exposure deserves to be fully investigated. Since the periplasmic space contains several proteins with crucial cellular functions, besides carbapenemases, we decided to study the periplasmic proteome of the multidrug-resistant (MDR) A. baumannii AB5075 strain, grown in the absence and presence of imipenem (IMP). Through the proteomic approach, 65 unique periplasmic proteins common in both growth conditions were identified: eight proteins involved in protein fate, response to oxidative stress, energy metabolism, antibiotic-resistance, were differentially expressed. Among them, ABUW_1746 and ABUW_2363 gene products presented the tetratricopeptide repeat motif, mediating protein-protein interactions. The expression switch of these proteins might determine specific protein interactions to better adapt to changing environmental conditions. ABUW_2868, encoding a heat shock protein likely involved in protection against oxidative stress, was upregulated in IMP-exposed bacteria. Accordingly, the addition of periplasmic proteins from A. baumannii cultured with IMP increased bacterial viability in an antioxidant activity assay. Overall, this study provides the first insights about the composition of the periplasmic proteins of a MDR A. baumannii strain, its biological response to IMP and suggests possible new targets to develop alternative antibiotic drugs.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Antibacterianos/farmacología , Imipenem/farmacología , Proteínas Periplasmáticas/metabolismo , Infecciones por Acinetobacter/microbiología , Aminoácidos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Relación Dosis-Respuesta a Droga , Farmacorresistencia Bacteriana , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estrés Oxidativo , Proteínas Periplasmáticas/genética , Fenotipo , Proteoma , Proteómica/métodos
6.
Microb Pathog ; 112: 274-278, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28987619

RESUMEN

Some Escherichia coli strains of phylogroup B2 harbor a (pks) pathogenicity island that encodes a polyketide-peptide genotoxin called colibactin. It causes DNA double-strand breaks and megalocytosis in eukaryotic cells and it may contribute to cancer development. Study of bacterial community that colonizes the adenomatous polyp lesion, defined as precancerous lesions, could be helpful to assess if such pathogenic bacteria possess a role in the polyp progression to cancer. In this cross-sectional study, a total of 1500 E. coli isolates were obtained from biopsies of patients presenting adenomatous colon polyps, the normal tissues adjacent to the polyp lesion and patients presenting normal mucosa. pks island frequency, phylogenetic grouping, fingerprint genotyping, and virulence gene features of pks positive (pks+) E. coli isolates were performed. We found pks+E. coli strongly colonize two patients presenting polypoid lesions and none were identified in patients presenting normal mucosa. Predominant phylogroups among pks+E. coli isolates were B2, followed by D. Clustering based on fragment profiles of composite analysis, typed the pks+ isolates into 5 major clusters (I-V) and 17 sub-clusters, demonstrating a high level of genetic diversity among them. The most prevalent virulence genes were fimH and fyuA (100%), followed by vat (92%), hra and papA (69%), ibeA (28%), and hlyA (25%). Our results revealed that pks+E. coli can colonize the precancerous lesions, with a high distribution in both the polyp lesions and in normal tissues adjacent to the lesion. The high differences in fingerprinting patterns obtained indicate that pks+E. coli strains were genetically diverse, possibly allowing them to more easily adapt to environmental variations.


Asunto(s)
Proteínas de Escherichia coli/genética , Escherichia coli/clasificación , Escherichia coli/genética , Variación Genética , Pólipos Intestinales/microbiología , Filogenia , Factores de Virulencia/genética , Adhesinas de Escherichia coli/genética , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Toxinas Bacterianas/genética , Biopsia , Estudios Transversales , ADN Bacteriano/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Proteínas Fimbrias/genética , Islas Genómicas , Genotipo , Proteínas Hemolisinas/genética , Humanos , Italia , Proteínas de la Membrana/genética , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Epidemiología Molecular , Péptidos/genética , Policétidos , Receptores de Superficie Celular/genética , Virulencia
7.
Infect Immun ; 84(11): 3105-3113, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27600504

RESUMEN

Adherent/invasive Escherichia coli (AIEC) strains have recently been receiving increased attention because they are more prevalent and persistent in the intestine of Crohn's disease (CD) patients than in healthy subjects. Since AIEC strains show a high percentage of similarity to extraintestinal pathogenic E. coli (ExPEC), neonatal meningitis-associated E. coli (NMEC), and uropathogenic E. coli (UPEC) strains, here we compared AIEC strain LF82 with a UPEC isolate (strain EC73) to assess whether LF82 would be able to infect prostate cells as an extraintestinal target. The virulence phenotypes of both strains were determined by using the RWPE-1 prostate cell line. The results obtained indicated that LF82 and EC73 are able to adhere to, invade, and survive within prostate epithelial cells. Invasion was confirmed by immunofluorescence and electron microscopy. Moreover, cytochalasin D and colchicine strongly inhibited bacterial uptake of both strains, indicating the involvement of actin microfilaments and microtubules in host cell invasion. Moreover, both strains belong to phylogenetic group B2 and are strong biofilm producers. In silico analysis reveals that LF82 shares with UPEC strains several virulence factors: namely, type 1 pili, the group II capsule, the vacuolating autotransporter toxin, four iron uptake systems, and the pathogenic island (PAI). Furthermore, compared to EC73, LF82 induces in RWPE-1 cells a marked increase of phosphorylation of mitogen-activated protein kinases (MAPKs) and of NF-κB already by 5 min postinfection, thus inducing a strong inflammatory response. Our in vitro data support the hypothesis that AIEC strains might play a role in prostatitis, and, by exploiting host-cell signaling pathways controlling the innate immune response, likely facilitate bacterial multiplication and dissemination within the male genitourinary tract.


Asunto(s)
Adhesión Bacteriana/fisiología , Células Epiteliales/microbiología , Escherichia coli/patogenicidad , Próstata/citología , Biopelículas/crecimiento & desarrollo , Línea Celular , Enfermedad de Crohn/microbiología , Células Epiteliales/metabolismo , Escherichia coli/fisiología , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/metabolismo , Humanos , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Fenotipo , Filogenia , Virulencia , Factores de Virulencia/metabolismo
8.
Int J Med Microbiol ; 305(1): 75-84, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25434600

RESUMEN

Through the action of the type three secretion system (T3SS) Shigella flexneri delivers several effectors into host cells to promote cellular invasion, multiplication and to exploit host-cell signaling pathways to modulate the host innate immune response. Although much progress has been made in the understanding of many type III effectors, the molecular and cellular mechanism of the OspB effector is still poorly characterized. In this study we present new evidence that better elucidates the role of OspB as pro-inflammatory factor at very early stages of infection. Indeed, we demonstrate that, during the first hour of infection, OspB is required for full activation of ERK1/2 and p38 MAPKs and the cytosolic phospholipase A(2) (cPLA(2)). Activation of cPLA(2) ultimately leads to the production and secretion of PMN chemoattractant metabolite(s) uncoupled with release of IL-8. Moreover, we also present evidence that OspB is required for the development of the full and promptly inflammatory reaction characteristic of S. flexneri wild-type infection in vivo. Based on OspB and OspF similarity (both effectors share similar transcription regulation, temporal secretion into host cells and nuclear localization) we hypothesized that OspB and OspF effectors may form a pair aimed at modulating the host cell response throughout the infection process, with opposite effects. A model is presented to illustrate how OspB activity would promote S. flexneri invasion and bacterial dissemination at early critical phases of infection.


Asunto(s)
Antígenos Bacterianos/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Citocinas/metabolismo , Interacciones Huésped-Patógeno , Factores Inmunológicos/metabolismo , Shigella flexneri/inmunología , Shigella flexneri/fisiología , Células CACO-2 , Células HeLa , Humanos , Transducción de Señal
9.
Pharmaceutics ; 15(2)2023 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-36839848

RESUMEN

Selective antiadhesion antagonists of Uropathogenic Escherichia coli (UPEC) type-1 Fimbrial adhesin (FimH) are attractive alternatives for antibiotic therapies and prophylaxes against acute or recurrent urinary tract infections (UTIs) caused by UPECs. A rational small library of FimH antagonists based on previously described C-linked allyl α-D-mannopyranoside was synthesized using Heck cross-coupling reaction using a series of iodoaryl derivatives. This work reports two new members of FimH antagonist amongst the above family with sub nanomolar affinity. The resulting hydrophobic aglycones, including constrained alkene and aryl groups, were designed to provide additional favorable binding interactions with the so-called FimH "tyrosine gate". The newly synthesized C-linked glycomimetic antagonists, having a hydrolytically stable anomeric linkage, exhibited improved binding when compared to previously published analogs, as demonstrated by affinity measurement through interactions by FimH lectin. The crystal structure of FimH co-crystallized with one of the nanomolar antagonists revealed the binding mode of this inhibitor into the active site of the tyrosine gate. In addition, selected mannopyranoside constructs neither affected bacterial growth or cell viability nor interfered with antibiotic activity. C-linked mannoside antagonists were effective in decreasing bacterial adhesion to human bladder epithelial cells (HTB-9). Therefore, these molecules constituted additional therapeutic candidates' worth further development in the search for potent anti-adhesive drugs against infections caused by UPEC.

10.
Microbiol Spectr ; 11(6): e0077523, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37795996

RESUMEN

IMPORTANCE: In this paper, we demonstrated that apyrase is released within the host cell cytoplasm during infection to target the intracellular ATP pool. By degrading intracellular ATP, apyrase contributes to prevent caspases activation, thereby inhibiting the activation of pyroptosis in infected cells. Our results show, for the first time, that apyrase is involved in the modulation of host cell survival, thereby aiding this pathogen to dampen the inflammatory response. This work adds a further piece to the puzzle of Shigella pathogenesis. Due to its increased spread worldwide, prevention and controlling strategies are urgently needed. Overall, this study highlighted apyrase as a suitable target for an anti-virulence therapy to tackle this pathogen.


Asunto(s)
Proteínas Bacterianas , Factores de Virulencia , Shigella flexneri , Apirasa , Células Eucariotas , Adenosina Trifosfato
11.
FEMS Microbes ; 4: xtad009, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333444

RESUMEN

Acinetobacter baumannii is a Gram-negative bacterium increasingly implicated in hospital-acquired infections and outbreaks. Effective prevention and control of such infections are commonly challenged by the frequent emergence of multidrug-resistant strains. Here we introduce Ab-web (https://www.acinetobacterbaumannii.no), the first online platform for sharing expertise on A. baumannii. Ab-web is a species-centric knowledge hub, initially with 10 articles organized into two main sections, 'Overview' and 'Topics', and three themes, 'epidemiology', 'antibiotic resistance', and 'virulence'. The 'workspace' section provides a spot for colleagues to collaborate, build, and manage joint projects. Ab-web is a community-driven initiative amenable to constructive feedback and new ideas.

12.
Front Mol Biosci ; 9: 1088783, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36619166

RESUMEN

Bacterial small RNAs (sRNAs) research has accelerated over the past decade, boosted by advances in RNA-seq technologies and methodologies for capturing both protein-RNA and RNA-RNA interactions. The emerging picture is that these regulatory sRNAs play important roles in controlling complex physiological processes and are required to survive the antimicrobial challenge. In recent years, the RNA content of OMVs/EVs has also gained increasing attention, particularly in the context of infection. Secreted RNAs from several bacterial pathogens have been characterized but the exact mechanisms promoting pathogenicity remain elusive. In this review, we briefly discuss how secreted sRNAs interact with targets in infected cells, thus representing a novel perspective of host cell manipulation during bacterial infection. During the last decade, Acinetobacter baumannii became clinically relevant emerging pathogens responsible for nosocomial and community-acquired infections. Therefore, we also summarize recent findings of regulation by sRNAs in A. baumannii and discuss how this emerging bacterium utilizes many of these sRNAs to adapt to its niche and become successful human pathogen.

13.
Artículo en Inglés | MEDLINE | ID: mdl-35270562

RESUMEN

In recent decades, Acinetobacter baumannii emerged as a major infective menace in healthcare settings due to scarce therapeutic options to treat infections. Therefore, undertaking genome comparison analyses of multi-resistant A. baumannii strains could aid the identification of key bacterial determinants to develop innovative anti-virulence approaches. Following genome sequencing, we performed a molecular characterization of key genes and genomic comparison of two A. baumannii strains, #36 and #150, with selected reference genomes. Despite a different antibiotic resistance gene content, the analyzed strains showed a very similar antibiogram profile. Interestingly, the lack of some important virulence determinants (i.e., bap, ata and omp33-36) did not abrogate their adhesive abilities to abiotic and biotic surfaces, as reported before; indeed, strains retained these capacities, although to a different extent, suggesting the presence of distinct vicarious genes. Conversely, secretion systems, lipopolysaccharide (LPS), capsule and iron acquisition systems were highly similar to A. baumannii reference strains. Overall, our analyses increased our knowledge on A. baumannii genomic content and organization as well as the genomic events occurring in nosocomial isolates to better fit into changing healthcare environments.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana/genética , Farmacorresistencia Bacteriana Múltiple/genética , Variación Genética , Humanos , Pruebas de Sensibilidad Microbiana , Virulencia/genética
14.
Pathogens ; 11(10)2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36297271

RESUMEN

Background: Anisakis spp. third-stage larvae (L3) are the causative agents of human zoonosis called anisakiasis. The accidental ingestion of L3 can cause acute and chronic inflammation at the gastric, intestinal, or ectopic levels. Despite its relevance in public health, studies on pathogenetic mechanisms and parasite-human interplay are scarce. The aim of this study was to investigate the human inflammatory response to different Anisakis vehicles of pathogenicity. Methods: Human colorectal adenocarcinoma (Caco-2) cells were exposed to Anisakis L3 (the initial contact with the host), extracellular vesicles (EVs, Anisakis-host communication), and crude extract (CE, the larval dying). The protein quantity and gene expression of two pro-inflammatory cytokines (IL-6 and IL-8) were investigated using an ELISA test (6 h and 24 h) and a qReal-Time PCR (1 h, 6 h, and 24 h), respectively. Results: The L3 and EVs induced a downregulation in both the Il-6 and Il-8 gene expression and protein quantity. On the contrary, the CE stimulated IL-6 gene expression and its protein release, not affecting IL-8. Conclusions: The Caco-2 cells seemed to not react to the exposure to the L3 and EVs, suggesting a parasite's immunomodulating action to remain alive in an inhospitable niche. Conversely, the dying larva (CE) could induce strong activation of the immune strategy of the host that, in vivo, would lead to parasite expulsion, eosinophilia, and/or granuloma formation.

15.
J Immunol Res ; 2022: 2054431, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35378905

RESUMEN

Interleukins (ILs)-which are important members of cytokines-consist of a vast group of molecules, including a wide range of immune mediators that contribute to the immunological responses of many cells and tissues. ILs are immune-glycoproteins, which directly contribute to the growth, activation, adhesion, differentiation, migration, proliferation, and maturation of immune cells; and subsequently, they are involved in the pro and anti-inflammatory responses of the body, by their interaction with a wide range of receptors. Due to the importance of immune system in different organisms, the genes belonging to immune elements, such as ILs, have been studied vigorously. The results of recent investigations showed that the genes pertaining to the immune system undergo progressive evolution with a constant rate. The occurrence of any mutation or polymorphism in IL genes may result in substantial changes in their biology and function and may be associated with a wide range of diseases and disorders. Among these abnormalities, single nucleotide polymorphisms (SNPs) can represent as important disruptive factors. The present review aims at concisely summarizing the current knowledge available on the occurrence, properties, role, and biological consequences of SNPs within the IL-1 family members.


Asunto(s)
Citocinas , Interleucina-1 , Citocinas/genética , Interleucina-1/genética , Interleucinas/genética , Polimorfismo de Nucleótido Simple
16.
Pathogens ; 10(4)2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33804894

RESUMEN

Acinetobacter baumannii is regarded as a life-threatening pathogen associated with community-acquired and nosocomial infections, mainly pneumonia. The rise in the number of A. baumannii antibiotic-resistant strains reduces effective therapies and increases mortality. Bacterial comparative genomic studies have unraveled the innate and acquired virulence factors of A. baumannii. These virulence factors are involved in antibiotic resistance, environmental persistence, host-pathogen interactions, and immune evasion. Studies on host-pathogen interactions revealed that A. baumannii evolved different mechanisms to adhere to in order to invade host respiratory cells as well as evade the host immune system. In this review, we discuss current data on A. baumannii genetic features and virulence factors. An emphasis is given to the players in host-pathogen interaction in the respiratory tract. In addition, we report recent investigations into host defense systems using in vitro and in vivo models, providing new insights into the innate immune response to A. baumannii infections. Increasing our knowledge of A. baumannii pathogenesis may help the development of novel therapeutic strategies based on anti-adhesive, anti-virulence, and anti-cell to cell signaling pathways drugs.

17.
Microorganisms ; 9(7)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206680

RESUMEN

Bacterial biofilms are a serious public-health problem worldwide. In recent years, the rates of antibiotic-resistant Gram-negative bacteria associated with biofilm-forming activity have increased worrisomely, particularly among healthcare-associated pathogens. Acinetobacter baumannii is a critically opportunistic pathogen, due to the high rates of antibiotic resistant strains causing healthcare-acquired infections (HAIs). The clinical isolates of A. baumannii can form biofilms on both biotic and abiotic surfaces; hospital settings and medical devices are the ideal environments for A. baumannii biofilms, thereby representing the main source of patient infections. However, the paucity of therapeutic options poses major concerns for human health infections caused by A. baumannii strains. The increasing number of multidrug-resistant A. baumannii biofilm-forming isolates in association with the limited number of biofilm-eradicating treatments intensify the need for effective antibiofilm approaches. This review discusses the mechanisms used by this opportunistic pathogen to form biofilms, describes their clinical impact, and summarizes the current and emerging treatment options available, both to prevent their formation and to disrupt preformed A. baumannii biofilms.

18.
J Virol Methods ; 287: 114008, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33160015

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the COVID-19 pandemic. Although other diagnostic methods have been introduced, detection of viral genes on oro- and nasopharyngeal swabs by reverse-transcription real time-PCR (rRT-PCR) assays is still the gold standard. Efficient viral RNA extraction is a prerequisite for downstream performance of rRT-PCR assays. Currently, several automatic methods that include RNA extraction are available. However, due to the growing demand, a shortage in kit supplies could be experienced in several labs. For these reasons, the use of different commercial or in-house protocols for RNA extraction may increase the possibility to analyze high number of samples. Herein, we compared the efficiency of RNA extraction of three different commercial kits and an in-house extraction protocol using synthetic ssRNA standards of SARS-CoV-2 as well as in oro-nasopharyngeal swabs from six COVID-19-positive patients. It was concluded that tested commercial kits can be used with some modifications for the detection of the SARS-CoV-2 genome by rRT-PCR approaches, although with some differences in RNA yields. Conversely, EXTRAzol reagent was the less efficient due to the phase separation principle at the basis of RNA extraction. Overall, this study offers alternative suitable methods to manually extract RNA that can be taken into account for SARS-CoV-2 detection.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , ARN Viral/aislamiento & purificación , SARS-CoV-2/aislamiento & purificación , Pruebas Diagnósticas de Rutina , Genes Virales/genética , Humanos , Límite de Detección , Faringe/virología , ARN Viral/análisis , ARN Viral/genética , Reproducibilidad de los Resultados , SARS-CoV-2/genética
19.
Adv Exp Med Biol ; 698: 1-16, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21520699

RESUMEN

The Nutra-Snacks project aims at creating novel high quality ready-to-eat foods with functional activity, useful for promoting public health. The team is composed of seven research institutes and three SMEs from different countries whose activities span from basic to applied research providing the right technological transfer to small and medium industries involved in the novel food production chain. Strategic objectives include the application of plant cell and in vitro culture systems to create very large amounts of high-value plant secondary metabolites with recognized anticancer, antilipidemic, anticholesterol, antimicrobial, antiviral, antihypertensive and anti-inflammatory properties and to include them in specific food products. To this end, the screening of a vast number of working organisms capable of accumulating the desired compounds and the characterization of their expression profiles represent fundamental steps in the research program. The information allows the identification of plant species hyper-producing metabolites and selection of those metabolites capable of specifically counteracting the oxidative stress that underlies the development of important pathologies and diseases. In addition, devising safe metabolite extraction procedures is also crucial in order to provide nutraceutical-enriched extracts compatible with human health. New biotechnological approaches are also undertaken including the exploitation of photosynthetic algal strains in bio-farms to enhance the synthesis ofantioxidant compounds and the design of novel bioreactors for small and large scale biomass production. Further outstanding objectives include the development of (i) safety and quality control protocols (ii) biosensor techniques for the analysis of the emerging ready-to-eat food and (iii) a contribution to define a standard for new regulations on nutraceutics.


Asunto(s)
Biotecnología/métodos , Suplementos Dietéticos , Alimentos Funcionales , Humanos , Estilo de Vida , Estrés Oxidativo , Plantas/química , Plantas/metabolismo , Salud Pública
20.
Cancers (Basel) ; 12(8)2020 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-32764361

RESUMEN

Over the past decade, short non-coding microRNAs (miRNAs), including circulating and fecal miRNAs have emerged as important modulators of various cellular processes by regulating the expression of target genes. Recent studies revealed the role of miRNAs as powerful biomarkers in disease diagnosis and for the development of innovative therapeutic applications in several human conditions, including intestinal diseases. In this review, we explored the literature and summarized the role of identified dysregulated fecal miRNAs in intestinal diseases, with particular focus on colorectal cancer (CRC) and celiac disease (CD). The aim of this review is to highlight one fascinating aspect of fecal miRNA function related to gut microbiota shaping and bacterial metabolism influencing. The role of miRNAs as "messenger" molecules for inter kingdom communications will be analyzed to highlight their role in the complex host-bacteria interactions. Moreover, whether fecal miRNAs could open up new perspectives to develop novel suitable biomarkers for disease detection and innovative therapeutic approaches to restore microbiota balance will be discussed.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA