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1.
Biofouling ; 40(1): 14-25, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38254292

RESUMEN

Acyl-homoserine lactones (AHLs) are quorum-sensing signaling molecules in Gram-negative bacteria and positively regulate biofilm formation in Salmonella under specific conditions. In this study, biofilm formation in Salmonella enterica was evaluated at 28 and 37 °C, under aerobic and anaerobic conditions. Additionally, the influence of the N-dodecanoyl-DL-homoserine lactone (C12-HSL) on biofilm formation and the expression of genes related to the synthesis of structural components, regulation, and quorum sensing was assessed under anaerobiosis at 28 and 37 °C. Biofilm formation was found not to be influenced by the atmospheric conditions at 28 °C. However, it was reduced at 37 °C under anaerobiosis. C12-HSL enhanced biofilm formation at 37 °C under anaerobiosis and increased the expression of the adrA and luxS genes, suggesting an increase in c-di-GMP, a second messenger that controls essential physiological functions in bacteria. These results provide new insights into the regulation of biofilm formation in Salmonella under anaerobic conditions.


Asunto(s)
Percepción de Quorum , Salmonella enteritidis , Percepción de Quorum/genética , Salmonella enteritidis/genética , Biopelículas , Anaerobiosis , 4-Butirolactona/farmacología , 4-Butirolactona/metabolismo , Acil-Butirolactonas
2.
Biochem Genet ; 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649558

RESUMEN

Hepatoblastoma stands as the most prevalent liver cancer in the pediatric population. Characterized by a low mutational burden, chromosomal and epigenetic alterations are key drivers of its tumorigenesis. Transcriptome analysis is a powerful tool for unraveling the molecular intricacies of hepatoblastoma, shedding light on the effects of genetic and epigenetic changes on gene expression. In this study conducted in Brazilian patients, an in-depth whole transcriptome analysis was performed on 14 primary hepatoblastomas, compared to control liver tissues. The analysis unveiled 1,492 differentially expressed genes (1,031 upregulated and 461 downregulated), including 920 protein-coding genes (62%). Upregulated biological processes were linked to cell differentiation, signaling, morphogenesis, and development, involving known hepatoblastoma-associated genes (DLK1, MEG3, HDAC2, TET1, HMGA2, DKK1, DKK4), alongside with novel findings (GYNG4, CDH3, and TNFRSF19). Downregulated processes predominantly centered around oxidation and metabolism, affecting amines, nicotinamides, and lipids, featuring novel discoveries like the repression of SYT7, TTC36, THRSP, CCND1, GCK and CAMK2B. Two genes, which displayed a concordant pattern of DNA methylation alteration in their promoter regions and dysregulation in the transcriptome, were further validated by RT-qPCR: the upregulated TNFRSF19, a key gene in the embryonic development, and the repressed THRSP, connected to lipid metabolism. Furthermore, based on protein-protein interaction analysis, we identified genes holding central positions in the network, such as HDAC2, CCND1, GCK, and CAMK2B, among others, that emerged as prime candidates warranting functional validation in future studies. Notably, a significant dysregulation of non-coding RNAs (ncRNAs), predominantly upregulated transcripts, was observed, with 42% of the top 50 highly expressed genes being ncRNAs. An integrative miRNA-mRNA analysis revealed crucial biological processes associated with metabolism, oxidation reactions of lipids and carbohydrates, and methylation-dependent chromatin silencing. In particular, four upregulated miRNAs (miR-186, miR-214, miR-377, and miR-494) played a pivotal role in the network, potentially targeting multiple protein-coding transcripts, including CCND1 and CAMK2B. In summary, our transcriptome analysis highlighted disrupted embryonic development as well as metabolic pathways, particularly those involving lipids, emphasizing the emerging role of ncRNAs as epigenetic regulators in hepatoblastomas. These findings provide insights into the complexity of the hepatoblastoma transcriptome and identify potential targets for future therapeutic interventions.

3.
Nat Mater ; 21(9): 1057-1065, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35788569

RESUMEN

Rechargeable batteries paired with sodium metal anodes are considered to be one of the most promising high-energy and low-cost energy-storage systems. However, the use of highly reactive sodium metal and the formation of sodium dendrites during battery operation have caused safety concerns, especially when highly flammable liquid electrolytes are used. Here we design and develop solvent-free solid polymer electrolytes (SPEs) based on a perfluoropolyether-terminated polyethylene oxide (PEO)-based block copolymer for safe and stable all-solid-state sodium metal batteries. Compared with traditional PEO SPEs, our results suggest that block copolymer design allows for the formation of self-assembled nanostructures leading to high storage modulus at elevated temperatures with the PEO domains providing transport channels even at high salt concentration (ethylene oxide/sodium = 8/2). Moreover, it is demonstrated that the incorporation of perfluoropolyether segments enhances the Na+ transference number of the electrolyte to 0.46 at 80 °C and enables a stable solid electrolyte interface. The new SPE exhibits highly stable symmetric cell-cycling performance at high current density (0.5 mA cm-2 and 1.0 mAh cm-2, up to 1,000 h). Finally, the assembled all-solid-state sodium metal batteries demonstrate outstanding capacity retention, long-term charge/discharge stability (Coulombic efficiency, 99.91%; >900 cycles with Na3V2(PO4)3 cathode) and good capability with high loading NaFePO4 cathode (>1 mAh cm-2).

4.
Appl Microbiol Biotechnol ; 107(21): 6573-6589, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37658163

RESUMEN

Spathaspora passalidarum is a xylose-fermenting microorganism promising for the fermentation of lignocellulosic hydrolysates. This yeast is more sensitive to ethanol than Saccharomyces cerevisiae for unclear reasons. An RNA-seq experiment was performed to identify transcriptional changes in S. passalidarum in response to ethanol and gain insights into this phenotype. The results showed the upregulation of genes associated with translation and the downregulation of genes encoding proteins involved in lipid metabolism, transporters, and enzymes from glycolysis and fermentation pathways. Our results also revealed that genes encoding heat-shock proteins and involved in antioxidant response were upregulated, whereas the osmotic stress response of S. passalidarum appears impaired under ethanol stress. A pseudohyphal morphology of S. passalidarum colonies was observed in response to ethanol stress, which suggests that ethanol induces a misperception of nitrogen availability in the environment. Changes in the yeast fatty acid profile were observed only after 12 h of ethanol exposure, coinciding with the recovery of the yeast xylose consumption ability. These findings suggest that the lack of fast membrane lipid adjustments, the halt in nutrient absorption and cellular metabolism, and the failure to induce the expression of osmotic stress-responsive genes are the main aspects underlying the low ethanol tolerance of S. passalidarum. KEY POINTS: • Ethanol stress halts Spathaspora passalidarum metabolism and fermentation • Genes encoding nutrient transporters showed downregulation under ethanol stress • Ethanol induces a pseudohyphal cell shape, suggesting a misperception of nutrients.

5.
Appl Microbiol Biotechnol ; 107(16): 5161-5178, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37389589

RESUMEN

Kefir is a fermented beverage made of a symbiotic microbial community that stands out for health benefits. Although its microbial profile is still little explored, its effects on modulation of gut microbiota and production of short-chain fatty acids (SCFAs) seems to act by improving brain health. This work aimed to analyze the microbiota profile of milk kefir and its effect on metabolism, oxidative stress, and in the microbiota-gut-brain axis in a murine model. The experimental design was carried out using C57BL-6 mice (n = 20) subdivided into groups that received 0.1 mL water or 0.1 mL (10% w/v) kefir. The kefir proceeded to maturation for 48 h, and then it was orally administered, via gavage, to the animals for 4 weeks. Physicochemical, microbiological, antioxidant analyzes, and microbial profiling of milk kefir beverage were performed as well as growth parameters, food intake, serum markers, oxidative stress, antioxidant enzymes, SCFAs, and metabarcoding were analyzed in the mice. Milk kefir had 76.64 ± 0.42% of free radical scavenging and the microbiota composed primarily by the genus Comamonas. Moreover, kefir increased catalase and superoxide dismutase (colon), and SCFAs in feces (butyrate), and in the brain (butyrate and propionate). Kefir reduced triglycerides, uric acid, and affected the microbiome of animals increasing fecal butyrate-producing bacteria (Lachnospiraceae and Lachnoclostridium). Our results on the brain and fecal SCFAs and the antioxidant effect found were associated with the change in the gut microbiota caused by kefir, which indicates that kefir positively influences the gut-microbiota-brain axis and contributes to the preservation of gut and brain health. KEY POINTS: • Milk kefir modulates fecal microbiota and SCFA production in brain and colon. • Kefir treatment increases the abundance of SCFA-producing bacteria. • Milk kefir increases antioxidant enzymes and influences the metabolism of mice.


Asunto(s)
Kéfir , Microbiota , Ratones , Animales , Kéfir/microbiología , Leche/metabolismo , Antioxidantes , Ratones Endogámicos C57BL , Heces/microbiología , Ácidos Grasos Volátiles/metabolismo , Butiratos , Encéfalo/metabolismo
6.
Mol Divers ; 27(1): 281-297, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35441971

RESUMEN

Botrytis cinerea, Rhizoctonia solani and Hemileia vastatrix are three species of phytopathogenic fungi behind major crop losses worldwide. These have been selected as target models for testing the fungicide potential of a series of bis(ylidene) cyclohexanones. Although some compounds of this chemical class are known to have inhibitory activity against human pathogens, they have never been explored for the control of phytopathogens until now. In the present work, bis(ylidene) cyclohexanones were synthesized through simple, fast and low-cost base- or acid-catalyzed aldol condensation reaction and tested in vitro against B. cinerea, R. solani and H. vastatrix. bis(pyridylmethylene) cyclohexanones showed the highest activity against the target fungi. When tested at 200 nmol per mycelial plug against R. solani., these compounds completely inhibited the mycelial growth, and the most active bis(pyridylmethylene) cyclohexanone compound had an IC50 of 155.5 nmol plug-1. Additionally, bis(pyridylmethylene) cyclohexanones completely inhibited urediniospore germination of H. vastatrix, at 125 µmol L-1. The most active bis(pyridylmethylene) cyclohexanone had an IC50 value of 4.8 µmol L-1, which was estimated as approximately 2.6 times lower than that found for the copper oxychloride-based fungicide, used as control. Additionally, these substances had a low cytotoxicity against the mammalian Vero cell line. Finally, in silico calculations indicated that these compounds present physicochemical parameters regarded as suitable for agrochemicals. Bis(ylidene) cyclohexanones may constitute promising candidates for the development of novel antifungal agents for the control of relevant fungal diseases in agriculture.


Asunto(s)
Antifúngicos , Fungicidas Industriales , Humanos , Ciclohexanonas , Enfermedades de las Plantas/microbiología , Hongos , Plantas
7.
Molecules ; 28(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37375373

RESUMEN

The interest in the consumption of edible flowers has increased since they represent a rich source of bioactive compounds, which are significantly beneficial to human health. The objective of this research was to access the bioactive compounds and antioxidant and cytotoxic properties of unconventional alternative edible flowers of Hibiscus acetosella Welw. Ex Hiern. The edible flowers presented pH value of 2.8 ± 0.00, soluble solids content of 3.4 ± 0.0 °Brix, high moisture content of about 91.8 ± 0.3%, carbohydrates (6.9 ± 1.2%), lipids (0.90 ± 0.17%), ashes (0.4 ± 0.0%), and not detectable protein. The evaluation of the scavenging activity of free radicals, such as 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), of the flower extract was better than the results observed for other edible flowers (507.8 ± 2.7 µM TE and 783.9 ± 30.8 µM TE, respectively) as well as the total phenolic composition (TPC) value (568.8 ± 0.8 mg GAE/g). These flowers are rich in organic acids and phenolic compounds, mainly myricetin, and quercetin derivatives, kaempferol, and anthocyanins. The extract showed no cytotoxicity for the cell lineages used, suggesting that the extract has no directly harmful effects to cells. The important bioactive compound identified in this study makes this flower especially relevant in the healthy food area due to its nutraceutical potential without showing cytotoxicity.


Asunto(s)
Antocianinas , Hibiscus , Humanos , Antocianinas/química , Antioxidantes/química , Fenoles/química , Extractos Vegetales/química , Flores/química
8.
Mol Psychiatry ; 26(10): 5592-5607, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33144711

RESUMEN

Although APP metabolism is being intensively investigated, a large fraction of its modulators is yet to be characterized. In this context, we combined two genome-wide high-content screenings to assess the functional impact of miRNAs and genes on APP metabolism and the signaling pathways involved. This approach highlighted the involvement of FERMT2 (or Kindlin-2), a genetic risk factor of Alzheimer's disease (AD), as a potential key modulator of axon guidance, a neuronal process that depends on the regulation of APP metabolism. We found that FERMT2 directly interacts with APP to modulate its metabolism, and that FERMT2 underexpression impacts axonal growth, synaptic connectivity, and long-term potentiation in an APP-dependent manner. Last, the rs7143400-T allele, which is associated with an increased AD risk and localized within the 3'UTR of FERMT2, induced a downregulation of FERMT2 expression through binding of miR-4504 among others. This miRNA is mainly expressed in neurons and significantly overexpressed in AD brains compared to controls. Altogether, our data provide strong evidence for a detrimental effect of FERMT2 underexpression in neurons and insight into how this may influence AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Humanos , Proteínas de la Membrana , Proteínas de Neoplasias , Plasticidad Neuronal/genética , Neuronas , Factores de Riesgo
9.
J Appl Microbiol ; 133(3): 1857-1871, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35766136

RESUMEN

AIM: To identify and analyse genes that encode pectinases in the genome of the fungus Colletotrichum lindemuthianum, evaluate the expression of these genes, and compare putative pectinases found in C. lindemuthianum with pectinases produced by other fungi and oomycetes with different lifestyles. METHODS AND RESULTS: Genes encoding pectinases in the genome of C. lindemuthianum were identified and analysed. The expression of these genes was analysed. Pectinases from C. lindemuthianum were compared with pectinases from other fungi that have different lifestyles, and the pectinase activity in some of these fungi was quantified. Fifty-eight genes encoding pectinases were identified in C. lindemuthianum. At least six types of enzymes involved in pectin degradation were identified, with pectate lyases and polygalacturonases being the most abundant. Twenty-seven genes encoding pectinases were differentially expressed at some point in C. lindemuthianum during their interactions with their host. For each type of pectinase, there were at least three isoenzyme groups. The number of pectinases present in fungi with different lifestyles seemed to be related more to the lifestyle than to the taxonomic relationship between them. Only phytopathogenic fungi showed pectate lyase activity. CONCLUSIONS: The collective results demonstrate the pectinolytic arsenal of C. lindemuthianum, with many and diverse genes encoding pectinases more than that found in other phytopathogens, which suggests that at least part of these pectinases must be important for the pathogenicity of the fungus C. lindemuthianum. SIGNIFICANCE AND IMPACT OF THE STUDY: Knowledge of these pectinases could further the understanding of the importance of this broad pectinolytic arsenal in the common bean infection and could be exploited for biotechnological purposes.


Asunto(s)
Colletotrichum , Fabaceae , Colletotrichum/genética , Fabaceae/microbiología , Hongos/metabolismo , Poligalacturonasa/genética , Poligalacturonasa/metabolismo
10.
Appl Microbiol Biotechnol ; 106(12): 4627-4641, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35759035

RESUMEN

Tegumentary leishmaniasis (TL) is a disease of high severity and incidence in Brazil, and Leishmania braziliensis is its main etiological agent. The inefficiency of control measures, such as high toxicity and costs of current treatments and the lack of effective immunoprophylactic strategies, makes the development of vaccines indispensable and imminent. In this light, the present work developed a gene encoding multiple T-cell (CD4+/CD8+) epitope, derived from conserved proteins found in Leishmania species and associated with TL, to generate a chimeric protein (rMEP/TL) and compose a vaccine formulation. For this, six T-cell epitopes were selected by immunoinformatics approaches from proteins present in the amastigote stage and associated with host-parasite interactions. The following formulations were then tested in an L. braziliensis murine infection model: rMEP/TL in saline or associated with MPLA-PHAD®. Our data revealed that, after immunization (three doses; 14-day intervals) and subsequent challenging, rMEP/TL and rMEP/TL + MPLA-vaccinated mice showed an increased production of key immunological biomarkers of protection, such as IgG2a, IgG2a/IgG1, NO, CD4+, and CD8+ T-cells with IFN-γ and TNF-α production, associated with a reduction in CD4+IL-10+ and CD8+IL-10+ T-cells. Vaccines also induced the development of central (CD44highCD62Lhigh) and effector (CD44highCD62Llow) memory of CD4+ and CD8+ T-cells. These findings, associated with the observation of lower rates of parasite burdens in the vaccinated groups, when compared to the control groups, suggest that immunization with rMEP/TL and, preferably, associated with an adjuvant, may be considered an effective tool to prevent TL. KEY POINTS: • Rational design approaches for vaccine development. • Central and effector memory of CD4+ and CD8+ T-cells. • Vaccine comprised of rMEP/TL plus MPLA as an effective tool to prevent TL.


Asunto(s)
Vacunas contra la Leishmaniasis , Leishmaniasis , Animales , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Epítopos de Linfocito T/genética , Inmunoglobulina G , Interleucina-10/metabolismo , Leishmaniasis/prevención & control , Vacunas contra la Leishmaniasis/genética , Ratones , Ratones Endogámicos BALB C
11.
BMC Vet Res ; 18(1): 115, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35331225

RESUMEN

Staphylococcus aureus is a leading cause of bovine mastitis worldwide. Despite some improved understanding of disease pathogenesis, progress towards new methods for the control of intramammary infections (IMI) has been limited, particularly in the field of vaccination. Although herd management programs have helped to reduce the number of clinical cases, S. aureus mastitis remains a major disease burden. This review summarizes the past 16 years of research on bovine S. aureus population genetics, and molecular pathogenesis that have been conducted worldwide. We describe the diversity of S. aureus associated with bovine mastitis and the geographical distribution of S. aureus clones in different continents. We also describe studies investigating the evolution of bovine S. aureus and the importance of host-adaptation in its emergence as a mastitis pathogen. The available information on the prevalence of virulence determinants and their functional relevance during the pathogenesis of bovine mastitis are also discussed. Although traits such as biofilm formation and innate immune evasion are critical for the persistence of bacteria, the current understanding of the key host-pathogen interactions that determine the outcome of S. aureus IMI is very limited. We suggest that greater investment in research into the genetic and molecular basis of bovine S. aureus pathogenesis is essential for the identification of novel therapeutic and vaccine targets.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Infecciones Estafilocócicas , Animales , Bovinos , Femenino , Mastitis Bovina/microbiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/genética , Factores de Virulencia/genética
12.
Curr Microbiol ; 79(4): 101, 2022 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-35150342

RESUMEN

Staphylococcus aureus is the main pathogen associated with bovine mastitis, an intramammary inflammation that leads to significant economic losses in dairy herds. Efforts have been made to identify the bacterial determinants important to the infective process but most of the studies are focused on surface and secreted proteins. Considering that virulence is affected by metabolism, in this study we contrasted the proteome of strains of S. aureus causing persistent subclinical (Sau302 and Sau340) and clinical bovine mastitis (RF122). Protein expressions from cytosolic fractions of bacteria grown under conditions mimicking the mastitic mammary glands are reported. A total of 342 proteins was identified, 52 of which were differentially expressed. Among those down-regulated in the subclinical strains were the two-component sensor histidine kinase SaeS and PurH, both involved in bacterial virulence. The ribosome hibernation promotion factor and the 50S ribosomal protein L13 were up-regulated suggesting that Sau302 and Sau340 modulate protein translation, a condition that may contribute to bacterial survival under stressful conditions. TRAP, a regulator possibly involved in pathogenesis, was expressed only in RF122 while proteins from the Isd system, involved in heme acquisition, were exclusive to Sau302 and Sau340. In summary, the metabolic differences suggest a reduced virulence of the strains causing subclinical mastitis which may contribute to the persistent infection seen in the animals.


Asunto(s)
Mastitis Bovina , Infecciones Estafilocócicas , Animales , Bovinos , Femenino , Proteómica , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/genética , Virulencia
13.
Fungal Genet Biol ; 157: 103624, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34536506

RESUMEN

The yeast Spathaspora passalidarum is able to produce ethanol from D-xylose and D-glucose. However, it is not clear how xylose metabolism is affected by D-glucose when both sugars are available in the culture medium. The aims of this work were to evaluate the influence of D-glucose on D-xylose consumption, ethanol production, gene expression, and the activity of key xylose-metabolism enzymes under both aerobic and oxygen-limited conditions. Ethanol yields and productivities were increased in culture media containing D-xylose as the sole carbon source or a mixture of D-xylose and D-glucose. S. passalidarum preferentially consumed D-glucose in the co-fermentations, which is consistent with the reduction in expression of genes encoding the key xylose-metabolism enzymes. In the presence of D-glucose, the specific activities of xylose reductase (XR), xylitol dehydrogenase (XDH), and xylulokinase (XK) were lower. Interestingly, in accordance with other studies, the presence of 2-deoxyglucose (2DG) did not inhibit the growth of S. passalidarum in culture medium containing D-xylose as the sole carbon source. This indicates that a non-canonical repression pathway is acting in S. passalidarum. In conclusion, the results suggest that D-glucose inhibits D-xylose consumption and prevents the D-xylose-mediated induction of the genes encoding XR, XDH, and XK.


Asunto(s)
Saccharomycetales , Xilosa , Glucosa , Saccharomyces cerevisiae
14.
Arch Microbiol ; 203(9): 5345-5361, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34387704

RESUMEN

Aspergillus sp. A31 and Curvularia geniculata P1 are endophytes that colonize the roots of Aeschynomene fluminensis Vell. and Polygonum acuminatum Kunth. in humid environments contaminated with mercury. The two strains mitigated mercury toxicity and promoted Oryza sativa L growth. C. geniculata P1 stood out for increasing the host biomass by fourfold and reducing the negative effects of the metal on photosynthesis. Assembling and annotation of Aspergillus sp. A31 and C. geniculata P1 genomes resulted in 28.60 Mb (CG% 53.1; 10,312 coding DNA sequences) and 32.92 Mb (CG% 50.72; 8,692 coding DNA sequences), respectively. Twelve and 27 genomes of Curvularia/Bipolaris and Aspergillus were selected for phylogenomic analyzes, respectively. Phylogenetic analysis inferred the separation of species from the genus Curvularia and Bipolaris into different clades, and the separation of species from the genus Aspergillus into three clades; the species were distinguished by occupied niche. The genomes had essential gene clusters for the adaptation of microorganisms to high metal concentrations, such as proteins of the phytoquelatin-metal complex (GO: 0090423), metal ion binders (GO: 0046872), ABC transporters (GO: 0042626), ATPase transporters (GO: 0016887), and genes related to response to reactive oxygen species (GO: 0000302) and oxidative stress (GO: 0006979). The results reported here help to understand the unique regulatory mechanisms of mercury tolerance and plant development.


Asunto(s)
Mercurio , Oryza , Aspergillus/genética , Curvularia , Endófitos , Mercurio/toxicidad , Filogenia , Raíces de Plantas
15.
Appl Microbiol Biotechnol ; 105(18): 6805-6817, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34432132

RESUMEN

Leishmania braziliensis is responsible for most cases of human tegumentary leishmaniasis (HTL) and has caused a wide range of clinical manifestations, including cutaneous (CL) and mucosal leishmaniasis (ML). The diagnosis is based on criteria that consider epidemiological data, clinical findings, and laboratory tests and is hard to establish. For laboratory tests, none of the assays available can be considered gold standards for disease detection. In addition, the Montenegro skin test, essential to supporting infectologists in the clinical management of the disease, is no longer available in Brazil. Thus, the aim of this study was to develop new targets to be used in diagnostic tests for HTL. In the first step, we carried out two-dimensional gel electrophoresis, followed by mass spectrometry, combined with heat map analysis and immunoproteomics approach, and disclosed eight proteins expressed in the amastigote stage specifically recognized by serum from CL and ML patients. A chimeric protein was designed based on the combination of thirteen linear B-cell epitopes, identified by immunoinformatics analysis, from L. braziliensis proteins. Our results showed that the strategy used in this work was successful in developing an antigen to be used in immunological assays (100.0% sensitivity and specificity) in the detection of HTL cases and in comparison with results obtained from an ELISA using soluble L. braziliensis antigen (SLb-Antigen) and immunofluorescence assay (Bio-Manguinhos/FIOCRUZ). The present technology opens the door for its use in field exams by means of an immunochromatographic test, which will be even more helpful in regions without laboratory structures.Key points• Rational strategy to develop antigens.• Integration between immunoproteomic and immunoinformatics analysis.• Chimeric protein shows high performance in HTL diagnosis.


Asunto(s)
Leishmania braziliensis , Leishmaniasis Cutánea , Ensayo de Inmunoadsorción Enzimática , Humanos , Leishmaniasis Cutánea/diagnóstico , Proteómica , Proteínas Recombinantes de Fusión
16.
J Nerv Ment Dis ; 209(3): 229-231, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33620916

RESUMEN

ABSTRACT: Wernicke encephalopathy (WE) results from thiamine deficiency. If undiagnosed or inadequately treated, WE evolves into Korsakoff syndrome (KS). We herein report a case of nonalcoholic Wernicke-Korsakoff syndrome (WKS) that resulted from malnutrition due to psychosis in a 42-years-old male patient. Thiamine deficiency was secondary to severe malnourishment due to poisoning delusions and daily life disorganization in a patient with previously unrecognized schizophrenia. Besides the presence of WE's classic triad of signs, brain magnetic resonance imaging showed also typical thalamic lesions. Furthermore, the patient also presented anterograde and retrograde amnesia, executive dysfunction, and confabulations, compatible with KS being already present. Intravenous treatment with thiamine was given for 37 days. Improvement in cognitive functions and brain imaging alterations was evident. Nevertheless, persistent WKS deficits were present. This case highlights the multiplicity of etiologies of WKS, namely, psychiatric, and its debilitating consequences if not promptly recognized and treated.


Asunto(s)
Síndrome de Korsakoff/etiología , Trastornos Psicóticos/complicaciones , Adulto , Encéfalo/diagnóstico por imagen , Humanos , Síndrome de Korsakoff/psicología , Imagen por Resonancia Magnética , Masculino , Neuroimagen , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/patología , Tálamo/diagnóstico por imagen , Tálamo/patología , Deficiencia de Tiamina/complicaciones , Deficiencia de Tiamina/etiología , Deficiencia de Tiamina/psicología
17.
J Invertebr Pathol ; 179: 107525, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33383067

RESUMEN

The growing spread of dengue, chikungunya and Zika viruses demand the development of new and environmentally safe control methods for their vector, the mosquito Aedes aegypti. This study aims to find novel larvicidal agents from mutualistic (endophytic and rhizospheric) or edaphic bacteria that have no action against non-target organisms. Eleven out of the 254 bacterial strains tested were able to kill Ae. aegypti larvae. Larvicidal activity did not depend on presence of cells, since culture supernatants or crude lipopeptide extracts (CLEs) killed the larvae. Bacillus safensis BacI67 and Bacillus paranthracis C21 supernatants were the best performing supernatants, displaying the lowest lethal concentrations (LC50 = 31.11 µL/mL and 45.84 µL/mL, respectively). Bacillus velezensis B64a and Bacillus velezensis B15 produced the best performing CLEs (LC50 = 0.11 mg/mL and 0.12 mg/mL, respectively). Mass spectrometry analysis of CLEs detected a mixture of surfactins, iturins, and fengycins. The samples tested were weakly- or non-toxic to mammalian cells (RAW 264.7 macrophages and VERO cells) and non-target organisms (Caenorhabditis elegans, Galleria mellonella, Scenedesmus obliquus, and Tetrahymena pyriformis) - especially B. velezensis B15 CLE. The biosynthetic gene clusters related to secondary metabolism identified by whole genome sequencing of the four best performing bacteria strains revealed clusters for bacteriocin, beta-lactone, lanthipeptide, non-ribosomal peptide synthetases, polyketide synthases (PKS), siderophores, T3PKS, type 1 PKS-like, terpenes, thiopeptides, and trans-AT-PKS. Purification of lipopeptides may clarify the mechanisms by which these extracts kill Ae. aegypti larvae.


Asunto(s)
Aedes/fisiología , Bacillus/metabolismo , Control de Mosquitos , Aedes/crecimiento & desarrollo , Aedes/microbiología , Animales , Caenorhabditis elegans/efectos de los fármacos , Chlorocebus aethiops , Larva/crecimiento & desarrollo , Larva/microbiología , Larva/fisiología , Ratones , Mariposas Nocturnas/efectos de los fármacos , Células RAW 264.7/efectos de los fármacos , Scenedesmus/efectos de los fármacos , Tetrahymena pyriformis/efectos de los fármacos , Pruebas de Toxicidad , Células Vero/efectos de los fármacos
18.
Ann Gen Psychiatry ; 20(1): 35, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34229687

RESUMEN

BACKGROUND: Suicide is one of the main causes of excess of premature death in psychotic patients. Published studies found that suicide risk begins in ultra-high risk of psychosis and continues in early years of the disease. Previous studies identifying predictive and risk factors associated with suicidality in first-episode psychosis (FEP) are highly inconsistent. Also, there are relatively few longitudinal studies on suicidal behaviour in FEP. The aim of this study was to examine prevalence, evolution and predictors of suicidal behaviour at baseline and the 12-month follow-up in patients presenting with FEP. METHODS: One hundred and eighteen patients presenting with FEP were recruited from two early psychosis units in Portugal. A comprehensive assessment examining socio-demographic and clinical characteristics was administered at baseline and the 12-month follow-up. Odds ratio were calculated using logistic regression analyses. McNemar test was used to evaluate the evolution of suicidal behaviour and depression prevalence from baseline to 12 months of follow-up. RESULTS: Follow-up data were available for 60 participants from the 118 recruited. Approximately 25.4% of the patients had suicidal behaviour at the baseline evaluation, with a significant reduction during the follow-up period to 13.3% (p = 0.035). A multivariate binary logistic regression showed that a history of suicidal behaviour and depression at baseline independently predicted suicidal behaviour at baseline, and a history of suicidal behaviour and low levels of total cholesterol predicted suicidal behaviour at the 12-month follow-up. A significant proportion of patients also had depression at the baseline evaluation (43.3%), with the last month of suicidal behaviour at baseline independently predicting depression at this time. CONCLUSIONS: The findings of our study indicate that suicidal behaviour was prevalent on the year after FEP. Patients with a history of suicidal behaviour, depression at baseline and low levels of cholesterol should undergo close evaluation, monitoring and possible intervention in order to reduce suicide risk in the early phases of psychosis.

19.
J Environ Manage ; 285: 112204, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33618138

RESUMEN

This work aimed to assess the elimination and inactivation of resistance-conferring plasmids (RCPs) present in suspension in secondary wastewater by solar photo-Fenton as these are important vectors for the dissemination of antimicrobial resistance. Experiments were performed in synthetic secondary wastewater (SWW) and municipal wastewater treatment plant effluent (MWWTPE). Solar photo-Fenton (50 mg L-1 of H2O2 and 30 mg L-1 of Fe2+) was carried out for 60 min at neutral pH by applying the intermittent iron addition strategy. The removal of RCPs was assessed by Real-Time Polymerase Chain Reaction (qPCR). The transformation of competent non-resistant E. coli was used to evaluate the inactivation of target RCPs harboring antibiotic resistance genes (ARGs) to ampicillin (pSB1A2) or kanamycin (pSB1K3) after treatment and controls. Solar photo-Fenton completely removed RCPs initially present in both matrixes (SWW and MWWTPE), showing enhanced performance compared to the dark Fenton process. Both RCPs were inactivated after 30 min of solar photo-Fenton treatment, while 60 min were necessary to achieve the same effect for the dark Fenton reaction under similar conditions. These results indicate the potential of solar photo-Fenton to improve wastewater quality and reduce the spread of antimicrobial resistance in the environment by hampering the discharge of cell-free RCPs present in suspension in MWWTP onto environmental waters.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Antibacterianos , ADN , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Peróxido de Hidrógeno , Oxidación-Reducción , Plásmidos/genética
20.
J Clin Microbiol ; 58(7)2020 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-32404479

RESUMEN

Neosporosis has become a concern since it is associated with abortion in cattle. Currently, in situ diagnosis is determined through anamnesis, evaluation of the history, and perception of the clinical signs of the herd. There is no practical and noninvasive test adapted to a large number of samples, which represents a gap for the use of new approaches that provide information about infections and the risks of herds. Here, we performed a search in the Neospora caninum genome by linear B-cell epitopes using immunoinformatic tools aiming to develop a chimeric protein with high potential to bind specifically to antibodies from infected cattle samples. An enzyme-linked immunosorbent assay with the new chimeric antigen was developed and tested with sera from natural field N. caninum-infected bovines. The cross-reactivity of the new antigen was also evaluated using sera from bovines infected by other abortive pathogens, including Trypanosoma vivax, Leptospira sp., Mycobacterium bovis, and Brucella abortus, and enzootic bovine leucosis caused by bovine leukemia virus, as well as with samples of animals infected with Toxoplasma gondii The assay using the chimeric protein showed 96.6% ± 3.4% of sensitivity in comparison to healthy animal sera. Meanwhile, in relation to false-positive results provided by cross-reactivity with others pathogens, the specificity value was 97.0% ± 2.9%. In conclusion, immunoinformatic tools provide an efficient platform to build an accurate protein to diagnose bovine neosporosis based on serum samples.


Asunto(s)
Enfermedades de los Bovinos , Coccidiosis , Neospora , Animales , Anticuerpos Antiprotozoarios , Bovinos , Enfermedades de los Bovinos/diagnóstico , Coccidiosis/diagnóstico , Coccidiosis/veterinaria , Ensayo de Inmunoadsorción Enzimática , Femenino , Neospora/genética , Embarazo , Proteínas Recombinantes de Fusión/genética , Pruebas Serológicas
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