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1.
Development ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39253748

RESUMO

Caenorhabditis elegans males undergo sex-specific tail tip morphogenesis (TTM) under the control of the DM-domain transcription factor DMD-3. To find genes regulated by DMD-3, We performed RNA-seq of laser-dissected tail tips. We identified 564 genes differentially expressed (DE) in wild-type males vs. dmd-3(-) males and hermaphrodites. The transcription profile of dmd-3(-) tail tips is similar to that in hermaphrodites. For validation, we analyzed transcriptional reporters for 49 genes and found male-specific or male-biased expression for 26 genes. Only 11 DE genes overlapped with genes found in a previous RNAi screen for defective TTM. GO enrichment analysis of DE genes finds upregulation of genes within the unfolded protein response pathway and downregulation of genes involved in cuticle maintenance. Of the DE genes, 40 are transcription factors, indicating that the gene network downstream of DMD-3 is complex and potentially modular. We propose modules of genes that act together in TTM and are coregulated by DMD-3, among them the chondroitin synthesis pathway and the hypertonic stress response.

2.
Ecol Lett ; 26(11): 1887-1897, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37671723

RESUMO

Species, through their traits, influence how ecosystems simultaneously sustain multiple functions. However, it is unclear how trait diversity sustains the multiple contributions biodiversity makes to people. Freshwater fisheries nourish hundreds of millions of people globally, but overharvesting and river fragmentation are increasingly affecting catches. We analyse how loss of nutritional trait diversity in consumed fish portfolios affects the simultaneous provisioning of six essential dietary nutrients using household data from the Amazon and Tonlé Sap, two of Earth's most productive and diverse freshwater fisheries. We find that fish portfolios with high trait diversity meet higher thresholds of required daily intakes for a greater variety of nutrients with less fish biomass. This beneficial biodiversity effect is driven by low redundancy in species nutrient content profiles. Our findings imply that sustaining the dietary contributions fish make to people given declining biodiversity could require more biomass and ultimately exacerbate fishing pressure in already-stressed ecosystems.


Assuntos
Ecossistema , Pesqueiros , Humanos , Animais , Biomassa , Biodiversidade , Água Doce , Nutrientes , Peixes
3.
J Neurosci Res ; 101(12): 1900-1913, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37787045

RESUMO

Control of breast-to-brain metastasis remains an urgent unmet clinical need. While chemotherapies are essential in reducing systemic tumor burden, they have been shown to promote non-brain metastatic invasiveness and drug-driven neurocognitive deficits through the formation of neurofibrillary tangles (NFT), independently. Now, in this study, we investigated the effect of chemotherapy on brain metastatic progression and promoting tumor-mediated NFT. Results show chemotherapies increase brain-barrier permeability and facilitate enhanced tumor infiltration, particularly through the blood-cerebrospinal fluid barrier (BCSFB). This is attributed to increased expression of matrix metalloproteinase 9 (MMP9) which, in turn, mediates loss of Claudin-6 within the choroid plexus cells of the BCSFB. Importantly, increased MMP9 activity in the choroid epithelium following chemotherapy results in cleavage and release of Tau from breast cancer cells. This cleaved Tau forms tumor-derived NFT that further destabilize the BCSFB. Our results underline for the first time the importance of the BCSFB as a vulnerable point of entry for brain-seeking tumor cells post-chemotherapy and indicate that tumor cells themselves contribute to Alzheimer's-like tauopathy.


Assuntos
Doença de Alzheimer , Neoplasias Encefálicas , Neoplasias da Mama , Humanos , Feminino , Metaloproteinase 9 da Matriz/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo
4.
Fish Shellfish Immunol ; 140: 108947, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37454879

RESUMO

Infectious pancreatic necrosis virus (IPNV) has proven to effectively evade the host antiviral responses. This study clarifies whether the modulation of the antiviral immune response exerted by IPNV involves epigenetic mechanisms. An in-silico characterization of the rainbow trout IFN1 and IFNγ2 promoters was performed, identifying the islands or sequences rich in CpG dinucleotides and the putative transcription factor binding sites (TBS) for both gene promoters. RTS11 cells (rainbow trout monocyte/macrophage) were infected with IPNV, and the course of viral infection was followed up to 48 h post infection (hpi). Infected cells showed increased IFN1 and IFNγ2 transcriptional expression at 6 and 24 hpi, respectively. IPNV infection caused increases and decreases in global IFNγ2 promoter methylation at 6 and 24 hpi, respectively. The CpG dinucleotides at positions -392 and + 38 of this promoter were the most sensitive to methylation changes. The IFN1 promoter remained fully unmethylated during the course of the infection, similar to the control. The changes in the methylation pattern observed for the IFNγ2 promoter were coincident with the changes in DNA methyltransferase (DNMT) expression levels, increasing at 6 hpi and decreasing below basal level at 24 hpi. Similarly, the H4 histones associated with the IFN1 and IFNγ2 promoters were hyperacetylated at 6 hpi, subsequently decreasing their acetylation below basal levels at 24 hpi, in both promoters. Coincidentally with the above, overexpression of histone acetyltransferase (HAT) was observed at 6 hpi and of histone deacetylase (HDAC) at 24 hpi, with return to baseline of HAT. These results suggest that IPNV would epigenetically modulate the expression of IFN1 by changing acetylation levels of the histones H4 associated with its promoter. Also, the modulation of the expression of IFNy2 would be by switching methylation/demethylation levels of its promoter, in addition to changes in acetylation levels of histones H4 associated with this promoter. This study is the first to demonstrate the effect of epigenetic reprogramming after IPNV infection in salmonid cells, demonstrating that promoter methylation/demethylation level and changes in the histone code associated with promoters may play a role in the modulation of the immune response induced by the virus.


Assuntos
Infecções por Birnaviridae , Doenças dos Peixes , Vírus da Necrose Pancreática Infecciosa , Oncorhynchus mykiss , Animais , Vírus da Necrose Pancreática Infecciosa/fisiologia , Histonas/genética , Antivirais , Epigênese Genética , Infecções por Birnaviridae/veterinária
5.
Molecules ; 27(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35684424

RESUMO

Different hybrids based on curcumin and resveratrol were previously synthesized and characterized by spectroscopic techniques. The most active molecules (3a, 3e, 3i, and 3k) were evaluated in vitro as an approach to determine the possible mechanism of action of the hybrids. The results indicated that the evaluated curcumin/resveratrol hybrids induce mitochondrial instability in SW620 and SW480 cells. Moreover, these molecules caused a loss in membrane integrity, suggesting an apoptotic process mediated by caspases after the treatment with compounds 3i (SW480) and 3k (SW620). In addition, the results suggest that the mechanism of action of the hybrids could be independent of the p53 status. Furthermore, hybrids 3e and 3i caused G0/G1 phase arrest, which highlights the potential of these molecules not only as cytotoxic but also as cytostatic compounds. Hybrids 3e and 3i caused a negative modulation of the matrix metalloproteinase 7 (MMP7) on SW480 cells. These curcumin resveratrol hybrids could be potential candidates for further investigations in the search for potential chemopreventive agents, even in those cases with resistance to conventional chemotherapy because of the lack of p53 expression or function. Molecular docking simulations showed that compounds 3e, 3i, and 3k bind efficiently to proapoptotic human caspases 3/7 proteins, as well as human MMP-7 and p53, which, in turn, could explain at the molecular level the in vitro cytotoxic effect of these compounds in SW480 and SW620 colon cancer cell lines.


Assuntos
Antineoplásicos , Neoplasias do Colo , Curcumina , Antineoplásicos/química , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Caspases/metabolismo , Quimioprevenção , Neoplasias do Colo/tratamento farmacológico , Curcumina/farmacologia , Curcumina/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Proteína Supressora de Tumor p53/metabolismo
6.
Molecules ; 26(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062841

RESUMO

We synthesized twelve hybrids based on curcumin and resveratrol, and their structures were elucidated by spectroscopic analysis. The chemopreventive potential of these compounds was evaluated against SW480 human colon adenocarcinoma cells, its metastatic derivative SW620, along with the non-malignant CHO-K1 cell line. Among the tested compounds, hybrids 3e and 3i (for SW480) and 3a, 3e and 3k (for SW620) displayed the best cytotoxic activity with IC50 values ranging from 11.52 ± 2.78 to 29.33 ± 4.73 µM for both cell lines, with selectivity indices (SI) higher than 1, after 48 h of treatment. Selectivity indices were even higher than those reported for the reference drug, 5-fluorouracil (SI = 0.96), the starting compound resveratrol (SI = 0.45) and the equimolar mixture of curcumin plus resveratrol (SI = 0.77). The previous hybrids showed good antiproliferative activity.


Assuntos
Antineoplásicos/síntese química , Neoplasias Colorretais/patologia , Curcumina/farmacologia , Resveratrol/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células CHO , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Cricetinae , Cricetulus , Curcumina/síntese química , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/farmacologia , Humanos , Resveratrol/síntese química , Rodaminas/farmacologia
7.
J Helminthol ; 95: e21, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33875027

RESUMO

We report the nearly complete mitochondrial genome of Rhabdosynochus viridisi - the first for this genus - achieved by combining shotgun sequencing of genomic and cDNA libraries prepared using low-input protocols. This integration of genomic information leads us to correct the annotation of the gene features. The mitochondrial genome consists of 13,863 bp. Annotation resulted in the identification of 12 protein-encoding genes, 22 tRNA genes and two rRNA genes. Three non-coding regions, delimited by three tRNAs, were found between the genes nad5 and cox3. A phylogenetic analysis grouped R. viridisi with three other species of diplectanid monogeneans for which mitochondrial genomes are available.


Assuntos
Peixes/parasitologia , Genoma Mitocondrial , Platelmintos , Animais , Filogenia , Platelmintos/genética
8.
Glob Chang Biol ; 26(10): 5509-5523, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32785968

RESUMO

Upstream range shifts of freshwater fishes have been documented in recent years due to ongoing climate change. River fragmentation by dams, presenting physical barriers, can limit the climatically induced spatial redistribution of fishes. Andean freshwater ecosystems in the Neotropical region are expected to be highly affected by these future disturbances. However, proper evaluations are still missing. Combining species distribution models and functional traits of Andean Amazon fishes, coupled with dam locations and climatic projections (2070s), we (a) evaluated the potential impacts of future climate on species ranges, (b) investigated the combined impact of river fragmentation and climate change and (c) tested the relationships between these impacts and species functional traits. Results show that climate change will induce range contraction for most of the Andean Amazon fish species, particularly those inhabiting highlands. Dams are not predicted to greatly limit future range shifts for most species (i.e., the Barrier effect). However, some of these barriers should prevent upstream shifts for a considerable number of species, reducing future potential diversity in some basins. River fragmentation is predicted to act jointly with climate change in promoting a considerable decrease in the probability of species to persist in the long-term because of splitting species ranges in smaller fragments (i.e., the Isolation effect). Benthic and fast-flowing water adapted species with hydrodynamic bodies are significantly associated with severe range contractions from climate change.


Assuntos
Mudança Climática , Rios , Animais , Ecossistema , Peixes , Água Doce
9.
Development ; 143(5): 799-809, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26811380

RESUMO

The heterochronic genes lin-28, let-7 and lin-41 regulate fundamental developmental transitions in animals, such as stemness versus differentiation and juvenile versus adult states. We identify a new heterochronic gene, lep-2, in Caenorhabditis elegans. Mutations in lep-2 cause a delay in the juvenile-to-adult transition, with adult males retaining pointed, juvenile tail tips, and displaying defective sexual behaviors. In both sexes, lep-2 mutants fail to cease molting or produce an adult cuticle. We find that LEP-2 post-translationally regulates LIN-28 by promoting LIN-28 protein degradation. lep-2 encodes the sole C. elegans ortholog of the Makorin (Mkrn) family of proteins. Like lin-28 and other heterochronic pathway members, vertebrate Mkrns are involved in developmental switches, including the timing of pubertal onset in humans. Based on shared roles, conservation and the interaction between lep-2 and lin-28 shown here, we propose that Mkrns, together with other heterochronic genes, constitute an evolutionarily ancient conserved module regulating switches in development.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Repressoras/fisiologia , Ribonucleoproteínas/fisiologia , Alelos , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Diferenciação Celular , Mapeamento Cromossômico , Hibridização Genômica Comparativa , Epistasia Genética , Feminino , Teste de Complementação Genética , Masculino , Dados de Sequência Molecular , Mutagênese , Mutação , Fenótipo , Interferência de RNA , Processamento Pós-Transcricional do RNA , Ribonucleoproteínas/genética , Transgenes
10.
Fish Shellfish Immunol ; 90: 1-11, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31015063

RESUMO

Francisella noatunensis subsp. noatunensis, the etiological agent of Francisellosis, affects a large number of farmed species such as Salmo salar. This species coexists with several native species in the same ecosystem, including Eleginops maclovinus. Our objective was to evaluate the susceptibility, presence of clinical symptoms, and the ability of Eleginops maclovinus to respond to Francisella infection. For this, healthy individuals were inoculated with 1.5 × 101, 1.5 × 105, and 1.5 × 1010 bact/µL of Francisella by intraperitoneal injection, subsequently the fish were sampled on days 1, 3, 7, 14, 21, and 28 post injection (dpi). At the end of the experiment, no mortality, nor internal and external clinical signs were observed, although in the high dose anaemia was detected. Additionally, bacteria were detected in all three doses, however there was replication at day 28 only in the liver in the high dose. Analysis of gene expression by qPCR showed that the spleen generated an immune response against infection from day 1 dpi, however at day 7 dpi most of the genes suffered repressed expression; observing over expression of the genes C3, NLRC3, NLRC5, MHCI, IgM. In contrast, expression in the anterior kidney did not vary significantly during the challenge. IgM quantification showed the production of antibodies in the medium and high doses. This study provides new knowledge about Francisella infection and the long-lasting and specific immune response generated by Eleginops maclovinus. It also demonstrates its susceptibility to Francisellosis where there is a difference in the immune response according to the tissue.


Assuntos
Imunidade Adaptativa , Francisella/fisiologia , Rim Cefálico/imunologia , Imunidade Inata , Perciformes/imunologia , Baço/imunologia , Animais , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Perciformes/microbiologia
11.
J Appl Microbiol ; 126(3): 771-779, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30489677

RESUMO

AIMS: In this study, the ability of the consortium MR-01 to degrade phenol was determined. The effects of this chemical on the taxonomy and the metabolic behaviour were analysed through metagenomics. METHODS AND RESULTS: Consortium MR-01 was acclimated in a sublethal concentration of phenol. After this process, the capacity to degrade this molecule was analysed. Results showed that degradation increased with the increment of the initial phenol concentration. Metagenomic analysis indicates that the consortium metabolized phenol under aerobic conditions using phenol 2-monooxygenase and the meta-cleavage pathway. Sequence of the enzymes involved in the phenol degradation was ascribed to the Actinomycetales and Chloroflexales orders, with relative abundances <1%. The most abundant genera were part of the Sphingomonadales order; however, the role of these species in the consortium is not clear. CONCLUSIONS: Consortium MR-01 degrades efficiently high concentrations of phenol. The participation of extremophiles in the degradation process and the emergence of beneficial metabolic dependencies between the community members are some of the strategies used by the consortium to survive and develop under harsh environmental conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: This is one of the few studies describing the taxonomy and metabolic profile of a phenol degrading consortium.


Assuntos
Bactérias/metabolismo , Microbiota , Fenol/metabolismo , Bactérias/classificação , Bactérias/enzimologia , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Metagenômica , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Filogenia
12.
Artigo em Inglês | MEDLINE | ID: mdl-31301421

RESUMO

The aim of this study was to examine the effects of Flavobacterium psychrophilum, a pathogen that is economically important in the aquaculture sector, on the neuroendocrine response of Oncorhynchus mykiss during a time course experiment with sampling at 0.5, 1, 2, 6, 10, and 30 days post injection (dpi). In the brain, serotonin (5HT) content increased in the infected group at all the measured time points, a similar pattern was observed for 5-hydroxyindole-3-acetic acid (5HIAA). Infected fish presented an increase in brain dopamine levels on day 0.5 and 1 dpi. A non-significant variation in noradrenaline levels was observed on all treatment days. Foregut 5-HT and 5-HIAA content in the infected group presented the highest 5-HT concentrations with 248.6 and 983.5 ng/g tissue at 0.5 dpi respectively. Midgut 5-HT and 5-HIAA levels presented the highest 5-HT concentrations, 486.9 ng/g tissue and 1006.4 ng/g tissue respectively, at the beginning of the experiment (0.5 dpi). 5-HT levels in the hindgut presented the highest concentrations with 233.9 ng/g tissue at 0.5 dpi, while 5-HIAA presented the highest concentrations, 690.5 ng/g tissue, at the same time point. After injection with F. psychrophilum the neuroendocrine response in rainbow trout was tissue dependent. Brain levels of 5HT and 5HIIA indicate that the neuroendocrine response increased together with dopamine following intramuscular infection. These increases are in line with reports from other authors, indicating an early response of catecholamines as neurotransmitters to stressful stimulus. In addition the intestinal response was also increased, implying that there could be a possible relationship between the serotonergic system at the intestinal level and the immune system.


Assuntos
Flavobacterium/fisiologia , Sistemas Neurossecretores/microbiologia , Oncorhynchus mykiss/microbiologia , Animais , Encéfalo/metabolismo , Dopamina/metabolismo , Hormônios/metabolismo , Ácido Hidroxi-Indolacético/metabolismo , Norepinefrina/metabolismo , Serotonina/metabolismo , Fatores de Tempo
13.
J Helminthol ; 93(2): 226-241, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29743130

RESUMO

In this study, molecular (ribosomal sequence data), morphological and cross-hybridization properties were used to identify a new Steinernema sp. from Florida, USA. Molecular and morphological data provided evidence for placing the novel species into Clade V, or the 'glaseri-group' of Steinernema spp. Within this clade, analysis of sequence data of the rDNA genes, 28S and internal transcribed spacer (ITS), depicted the novel species as a distinctive entity and closely related to S. glaseri and S. cubanum. Additionally, cross-hybridization assays showed that the new species is unable to interbreed with either of the latter two species, reinforcing its uniqueness from a biological species concept standpoint. Key morphological diagnostic characters for S. khuongi n. sp. include the mean morphometric features of the third-stage infective juveniles: total body length (average: 1066 µm), tail length (average: 65 µm), location of the excretory pore (average: 80.5 µm) and the values of c (average: 16.4), D% (average: 60.5), E% (average: 126) and H% (average: 46.6). Additionally, males can be differentiated from S. glaseri and S. cubanum by the values of several ratios: D% (average: 68), E% (average: 323) and SW% (average: 120). The natural distribution of this species in Florida encompasses both natural areas and citrus groves, primarily in shallow groundwater ecoregions designated as 'flatwoods'. The morphological, molecular, phylogenetic and ecological data associated with this nematode support its identity as a new species in the S. glaseri-group.


Assuntos
Rabditídios/classificação , Rabditídios/patogenicidade , Animais , DNA de Helmintos/genética , DNA Ribossômico/genética , Florida , Larva/parasitologia , Mariposas/parasitologia , Filogenia , RNA Ribossômico 28S/genética , Rabditídios/anatomia & histologia , Análise de Sequência de DNA , Solo/parasitologia
14.
J Fish Dis ; 41(5): 773-782, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29315698

RESUMO

This is the first study to isolate, identify and characterize Streptococcus iniae as the causative disease agent in two tilapia (Oreochromis aureus) populations. The populations were geographically isolated, of distinct origins, and did not share water sources. Affected fish showed various external (e.g., exophthalmia and cachexia, among others) and internal (e.g., granulomatous septicaemia and interstitial nephritis, among others) signs. All internal organ samples produced pure cultures, two of which (one from each farm, termed S-1 and S-2) were subjected to biochemical, PCR and 16S rRNA sequencing (99.5% similarity) analyses, confirming S. iniae identification. The two isolates presented genetic homogeneity regardless of technique (i.e., RAPD, REP-PCR and ERIC-PCR analyses). Pathogenic potentials were assessed through intraperitoneal injection challenges in rainbow trout (Oncorhynchus mykiss) and zebrafish (Danio rerio). Rainbow trout mortalities were respectively 40% and 70% at 104 and 106  CFU per fish with the S-1 isolate, while 100% mortality rates were recorded in zebrafish at 102 and 104  CFU per fish with the S-2 isolate. The obtained data clearly indicate a relationship between intensified aquaculture activities in Mexico and new disease appearances. Future studies should establish clinical significances for the tilapia industry.


Assuntos
Ciclídeos , Doenças dos Peixes/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus iniae/isolamento & purificação , Animais , México , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Análise de Sequência de RNA , Infecções Estreptocócicas/microbiologia , Streptococcus iniae/genética
15.
Fungal Genet Biol ; 100: 52-60, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28215981

RESUMO

Debaryomyces hansenii is a halotolerant and Na+-includer yeast that can be isolated from different food and low-water activity products. It has also been defined as a marine-occurring yeast but key aspects for this salt tolerant behavior are far from being understood. Here, we searched for clues helping to elucidate the basis of this ability. Our results on growth, Rb+ transport, total K+ and Na+ content and vacuolar fragmentation are compatible with a yeast species adapted to cope with salt stress. On the other hand, we confirmed the existence of D. hansenii strategies that are generally observed in sensitive organisms, such as the production of glycerol as a compatible solute and the efficient vacuolar sequestration of Na+. We propose a striking role of D. hansenii vacuoles in the maintenance of constant cytosolic K+ values, even in the presence of extracellular Na+ concentration values more than two orders of magnitude higher than extracellular K+. Finally, the ability to deal with cytosolic Na+ levels significantly higher than those found in S. cerevisiae, shows the existence of important and specific salt tolerance mechanisms and determinants in D. hansenii.


Assuntos
Adaptação Fisiológica/genética , Debaryomyces/metabolismo , Tolerância ao Sal , Vacúolos/metabolismo , Cátions/metabolismo , Debaryomyces/crescimento & desenvolvimento , Glicerol/metabolismo , Concentração de Íons de Hidrogênio , Potássio/metabolismo , Sódio/metabolismo , Vacúolos/química , Vacúolos/genética
16.
Arch Microbiol ; 199(1): 77-84, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27535833

RESUMO

Tannins are polyphenolic compounds that cause astringent flavor and turbidity in food. Tannase is an enzyme that catalyzes the hydrolysis of tannins and is used in food industry. This study was conducted to determine the genetic variability and the tannase alleles variation in fungal strains isolated from soil and plants at five extreme areas of Coahuila, México. Two screening assays under 1 and 20 % of tannic acid were performed, with the isolations. In these assays, it was possible to identify 756 and 128 fungal strains, respectively. The major fungal variability was observed in "Cuatro Ciénegas" with 26 strains. The microorganisms were distributed in 11 groups, which correspond to Aspergillus section Nigri. AN7 and AN1 groups showed the major number of isolates from "Paila" and "Cuatro Ciénegas" locations, respectively. In the last location, the major diversity and specific richness were found. But in "Ojo Caliente," tannase allele conservations were observed.


Assuntos
Aspergillus/isolamento & purificação , Aspergillus/metabolismo , Taninos/metabolismo , Aspergillus/enzimologia , Aspergillus/genética , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Ambientes Extremos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , México , Plantas/microbiologia , Microbiologia do Solo
17.
Eur J Clin Microbiol Infect Dis ; 36(6): 965-969, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28243758

RESUMO

Guatemala is a developing country in Central America with a high burden of HIV and endemic fungal infections; we attempted to estimate the burden of serious fungal infections for the country. A full literature search was done to identify epidemiology papers reporting fungal infections from Guatemala. We used specific populations at risk and fungal infection frequencies in the population to estimate national rates. The population of Guatemala in 2013 was 15.4 million; 40% were younger than 15 and 6.2% older than 60. There are an estimated 53,000 adults with HIV infection, in 2015, most presenting late. The estimated cases of opportunistic fungal infections were: 705 cases of disseminated histoplasmosis, 408 cases of cryptococcal meningitis, 816 cases of Pneumocystis pneumonia, 16,695 cases of oral candidiasis, and 4,505 cases of esophageal candidiasis. In the general population, an estimated 5,568 adult asthmatics have allergic bronchopulmonary aspergillosis (ABPA) based on a 2.42% prevalence of asthma and a 2.5% ABPA proportion. Amongst 2,452 pulmonary tuberculosis patients, we estimated a prevalence of 495 for chronic pulmonary aspergillosis in this group, and 1,484 for all conditions. An estimated 232,357 cases of recurrent vulvovaginal candidiasis is likely. Overall, 1.7% of the population are affected by these conditions. The true fungal infection burden in Guatemala is unknown. Tools and training for improved diagnosis are needed. Additional research on prevalence is needed to employ public health measures towards treatment and improving the reported data of fungal diseases.


Assuntos
Micoses/epidemiologia , Micoses/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Comorbidade , Feminino , Guatemala/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
18.
Curr Microbiol ; 74(6): 691-701, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28332163

RESUMO

The aim of this study was to evaluate the fermentation of dietary fiber from green bean (Phaseolus vulgaris) and prickly pear shell (Opuntia ficus-indica) by Lactobacillus acidophilus LA-5 and Bifidobacterium bifidum 450B growing as mono-culture and co-culture, the fermentation products, and proteins expressed during this process. The analysis of the fermentation profile showed a major growth of bacteria in the culture media of each dietary fiber supplemented with glucose, and particularly B. bifidum 450B at 48 h showed the highest growth. In the case of the co-culture, the growth was lower indicating the possible negative interaction between L. acidophilus LA-5 and B. bifidum 450B and may be due to the less amount of carbohydrates and the high content of non-soluble fiber that affected the nutrients availability for the bacterial strains. The pH changes indicated the presence of short-chain fatty acids (SCFAs), being acetate (46-100%) the main SCFA. Changes in the proteome concerned proteins that are involved in carbohydrate and other carbohydrate pathways. The characterization of the bacteria according to the growth, metabolites, and proteins expressed allows understanding the response to the change of environmental conditions and could be useful to understand L. acidophilus LA-5 and B. bifidum 450B strains' adaptation to specific applications.


Assuntos
Bifidobacterium bifidum/metabolismo , Fibras na Dieta/metabolismo , Lactobacillus acidophilus/metabolismo , Opuntia/metabolismo , Phaseolus/metabolismo , Microbiologia Ambiental , Ácidos Graxos Voláteis/metabolismo , Fermentação/fisiologia
19.
J Fish Dis ; 39(11): 1275-1283, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27696458

RESUMO

Renibacterium salmoninarum is the causative agent of bacterial kidney disease, which significantly affects salmonid farming worldwide. Despite this impact, there is scarce data on its iron uptake ability, a factor of pathogenesis. This study investigated the iron acquisition mechanisms of R. salmoninarum and its capacity to uptake iron from different sources. Thirty-two Chilean isolates and the DSM20767T type strain grew in the presence of 2,2'-Dipyridyl at varying concentrations (250-330 µm), and all isolates positively reacted on chrome azurol S agar. Subsequently, inocula of four Chilean isolates and the type strain were prepared with or without 200 µm of 2,2'-Dipyridyl for uptake assays. Assay results revealed differences between the isolates in terms of iron acquisition. While a prior iron-limited environment was, for most isolates, not required to activate the uptake of iron (II) sulphate, ammonium iron (III) citrate or iron (III) chloride at higher concentrations (100 µm), it did facilitate growth at lower iron concentrations (10 µm and 1 µm). An exception was the H-2 isolate, which only grew with 100 µm of iron sulphide. In turn, 100 µm of haemin was toxic when isolates were grown in normal KDM-2. In silico R. salmoninarumATCC 33209T genome analysis detected various genes coding iron uptake-related proteins. This is the first study indicating two iron acquisition systems in R. salmoninarum: one involving siderophores and another involving haem group utilization. These data represent a first step towards fully elucidating this virulence factor in the pathogenic R. salmoninarum.


Assuntos
Infecções por Actinomycetales/veterinária , Doenças dos Peixes/microbiologia , Ferro/metabolismo , Micrococcaceae/metabolismo , Salmo salar , Sideróforos/metabolismo , Infecções por Actinomycetales/metabolismo , Infecções por Actinomycetales/microbiologia , Animais , Chile , Doenças dos Peixes/metabolismo , Rim/microbiologia , Nefropatias/metabolismo , Nefropatias/microbiologia , Nefropatias/veterinária
20.
Curr Ther Res Clin Exp ; 83: 8-12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27668025

RESUMO

BACKGROUND: The use of topical antimicrobial agents for management of minor skin infections is a clinical strategy that is commonly practiced in the community. Coupled with the use of topical antimicrobial agents is the emergence of antibiotic-resistant strains of pathogens leading to the need for alternative treatments. OBJECTIVE: A novel topical combination ointment consisting of salicylic acid, oak bark extract, benzoic acid, and polyethylene glycol (Bensal HP, Sonar products Inc., Carlstadt, NJ) with antimicrobial properties was assessed to determine its spectrum of activity. METHODS: One hundred eighty-four bacterial and fungal isolates from culture collections that included multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter spp, and gram-negative so-called superbugs, as well as yeasts and filamentous fungi, were investigated by cylinder diffusion and agar dilution assays. RESULTS: All 184 bacterial and fungal isolates were susceptible to the combination ointment at the clinically applied concentration and there was no evidence of cross-resistance between Bensal HP and other classes of antimicrobials. In time-kill tests, Bensal HP was rapidly bactericidal against P aeruginosa ATCC 27853 and methicillin-resistant S aureus SA179 at 4 × the MIC, a concentration that is applied clinically. CONCLUSIONS: The results of this study suggest that this combination ointment has a broad in vitro spectrum of antimicrobial activity against both more common bacterial and fungal pathogens and may be particularly useful for treatment of infections by multidrug-resistant organisms. Additional studies are warranted to investigate the full clinical utility as a therapeutic agent and also for possible infection control interventions.

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