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1.
J Med Virol ; 96(6): e29764, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38923577

RESUMEN

The cervicovaginal microbiome may contribute to human papillomavirus (HPV)-associated cervical carcinogenesis, but studies have been limited by low-resolution analysis methods. Using a high-resolution bioinformatics pipeline, we evaluated the relationship of the cervicovaginal microbiome with HPV and cervical intraepithelial neoplasia (CIN). The cervicovaginal microbiome of 186 women was characterized by sequencing 16S rRNA regions (V3-V4 and V5-V6) and annotated with the high-resolution ANCHOR pipeline. Samples were genotyped for HPV using the Roche-Cobas 4800 assay. We fitted logistic regression models using stepwise forward selection to select species (presence/absence) as correlates of CIN1+ and constructed a linear microbiome-based score using the regression coefficients. An HPV-based score was calculated from a separate logistic regression model to detect CIN1+ . Receiver operating characteristic curve analyses were performed; the area under the curve (AUC) and 95% confidence intervals (CI) were compared between scores. Overall, 66.7% of participants were HPV-positive. 77 unique species were identified: 8 using V3-V4, 48 using V5-V6, and 21 shared. Twelve species were retained via stepwise selection. The AUCs for the microbiome-, and HPV-based scores were 0.7656 (95% CI 0.6885-0.8426), and 0.7529 (95% CI 0.6855-0.8204), respectively. Bacterial species may be involved in cervical carcinogenesis as the microbiome- and HPV-based scores performed similarly for CIN1+ detection.


Asunto(s)
Carcinogénesis , Cuello del Útero , Microbiota , Papillomaviridae , Infecciones por Papillomavirus , ARN Ribosómico 16S , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Vagina , Humanos , Femenino , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/microbiología , Infecciones por Papillomavirus/complicaciones , Adulto , Vagina/microbiología , Vagina/virología , Cuello del Útero/microbiología , Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/microbiología , Displasia del Cuello del Útero/microbiología , Displasia del Cuello del Útero/virología , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Papillomaviridae/clasificación , ARN Ribosómico 16S/genética , Persona de Mediana Edad , Genotipo , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/genética , Adulto Joven , Virus del Papiloma Humano
2.
Gut ; 72(6): 1143-1154, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36585238

RESUMEN

OBJECTIVE: Colorectal cancer (CRC) is the third most diagnosed cancer, and requires surgical resection and reconnection, or anastomosis, of the remaining bowel to re-establish intestinal continuity. Anastomotic leak (AL) is a major complication that increases mortality and cancer recurrence. Our objective is to assess the causal role of gut microbiota in anastomotic healing. DESIGN: The causal role of gut microbiota was assessed in a murine AL model receiving faecal microbiota transplantation (FMT) from patients with CRC collected before surgery and who later developed or not, AL. Anastomotic healing and gut barrier integrity were assessed after surgery. Bacterial candidates implicated in anastomotic healing were identified using 16S rRNA gene sequencing and were isolated from faecal samples to be tested both in vitro and in vivo. RESULTS: Mice receiving FMT from patients that developed AL displayed poor anastomotic healing. Profiling of gut microbiota of patients and mice after FMT revealed correlations between healing parameters and the relative abundance of Alistipes onderdonkii and Parabacteroides goldsteinii. Oral supplementation with A. onderdonkii resulted in a higher rate of leaks in mice, while gavage with P. goldsteinii improved healing by exerting an anti-inflammatory effect. Patients with AL and mice receiving FMT from AL patients presented upregulation of mucosal MIP-1α, MIP-2, MCP-1 and IL-17A/F before surgery. Retrospective analysis revealed that patients with AL present higher circulating neutrophil and monocyte counts before surgery. CONCLUSION: Gut microbiota plays an important role in surgical colonic healing in patients with CRC. The impact of these findings may extend to a vast array of invasive gastrointestinal procedures.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Ratones , Animales , Citocinas , Microbioma Gastrointestinal/fisiología , Estudios Retrospectivos , ARN Ribosómico 16S , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/microbiología , Neoplasias Colorrectales/cirugía
3.
Int J Cancer ; 152(10): 2052-2060, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36650690

RESUMEN

In Costa Rica (CR), only one report on head and neck cancer (HNC) incidence trends (1985-2007) has been published and no investigations on the epidemiology of potentially human papillomavirus (HPV)-related and HPV-unrelated HNCs have been done. We examined the age-standardized incidence rates (IRs) and trends of head and neck squamous cell carcinomas (HNSCC) and compared incidence trends of potentially HPV-related and HPV-unrelated HNSCCs. We obtained all available HNC cases for the period 2006-2015 from the Costa Rican National Cancer Registry of Tumors and the population estimates from the Costa Rican National Institute of Statistics and Census. The analysis was restricted to invasive HNSCCs (n = 1577). IRs and incidence rate ratios were calculated using SEER*Stat software and were age-standardized for the 2010 Costa Rican population. Joinpoint regression analysis program was used to calculate trends and annual percent changes (APCs) in rates. For all HNSCCs, the age-standardized IR was 34.0/million person-years; 95% CI 32.4, 35.8. There was a significant decline in the incidence of nasopharyngeal cancer (APC: -5.9% per year; 95% CI -10.8, -0.7) and laryngeal cancer (APC: -5.4% per year; -9.2, 1.5). The incidence trends for hypopharyngeal, oropharyngeal and oral cavity cancers each remained stable over time. HNSCCs were categorized by their potential relatedness to HPV infection. Though the APCs were not statistically significant, IRs of potentially HPV-related HNSCCs trended upward, while HPV-unrelated HNSCCs trended downward. HNSCCs are uncommon in CR and decreased over time. We observed a divergent pattern of decreasing HPV-unrelated with increasing HPV-related HNSCCs that should be further informed by HPV genotyping tumor samples.


Asunto(s)
Neoplasias de Cabeza y Cuello , Neoplasias Nasofaríngeas , Infecciones por Papillomavirus , Humanos , Adulto , Carcinoma de Células Escamosas de Cabeza y Cuello , Incidencia , Virus del Papiloma Humano , Costa Rica
4.
Environ Microbiol ; 25(12): 2897-2912, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36975075

RESUMEN

The herbicide glyphosate has several potential entry points into composting sites and its impact on composting processes has not yet been evaluated. To assess its impact on bacterial diversity and abundance as well as on community composition and dynamics, we conducted a mesocosm experiment at the Montreal Botanical Garden. Glyphosate had no effect on physicochemical property evolution during composting, while it was completely dissipated by the end of the experiment. Sampling at Days 0, 2, 28 and 112 of the process followed by 16S rRNA amplicon sequencing also found no effect of glyphosate on species richness and community composition. Differential abundance analyses revealed an increase of a few taxa in the presence of glyphosate, namely TRA3-20 (order Polyangiales), Pedosphaeraceae and BIrii41 (order Burkholderiales) after 28 days. In addition, five amplicon sequence variants (ASVs) had lower relative abundance in the glyphosate treatment compared to the control on Day 2, namely Comamonadaceae, Pseudomonas sp., Streptomyces sp., Thermoclostridium sp. and Actinomadura keratinilytica, while two ASVs were less abundant on Day 112, namely Pedomicrobium sp. and Pseudorhodoplanes sp. Most differences in abundance were measured between the different sampling points within each treatment. These results present glyphosate as a poor determinant of species recruitment during composting.


Asunto(s)
Compostaje , Herbicidas , Streptomyces , Glifosato , ARN Ribosómico 16S/genética , Herbicidas/farmacología , Streptomyces/genética
5.
Environ Microbiol ; 24(5): 2516-2542, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35466495

RESUMEN

Conventional wastewater treatment relies on a complex microbiota; however, much of this community is still to be characterized. To better understand the origin, dynamics and fate of bacteria within a wastewater treatment plant: untreated primary wastewater, activated sludge and post-treatment effluent were characterized. From 3163 exact sequence variants (ESVs), 860 were annotated to species-level. In primary wastewater, 28% of ESVs were putative bacterial species previously associated with humans, 14% with animals and 5% as common to the environment. Differential abundance analysis revealed significant relative reductions in ESVs from potentially human-associated species from primary wastewater to activated sludge, and significant increases in ESVs from species associated with nutrient cycling. Between primary wastewater and effluent, 51% of ESVs from human-associated species did not significantly differ, and species such as Bacteroides massiliensis and Bacteroides dorei increased. These findings illustrate that activated sludge increased extracellular protease and urease-producing species, ammonia and nitrite oxidizers, denitrifiers and specific phosphorus accumulators. Although many human-associated species declined, some persisted in effluent, including strains of potential health or environmental concern. Species-level microbial assessment may be useful for understanding variation in wastewater treatment efficiency as well as for monitoring the release of microbes into surface water and the wider ecosystem.


Asunto(s)
Microbiota , Purificación del Agua , Bacterias/genética , Aguas del Alcantarillado/microbiología , Aguas Residuales/microbiología
6.
Chembiochem ; 23(20): e202200345, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-35995730

RESUMEN

Microviridins are a prominent family of ribosomally synthesized and posttranslationally modified peptides (RiPPs) featuring characteristic lactone and lactam rings. Their unusual cage-like architecture renders them highly potent serine protease inhibitors of which individual variants specifically inhibit different types of proteases of pharmacological interest. While posttranslational modifications are key for the stability and bioactivity of RiPPs, additional attractive properties can be introduced by functional tags. To date - although highly desirable - no method has been reported to incorporate functional tags in microviridin scaffolds or the overarching class of graspetides. In this study, a chemoenzymatic in vitro platform is used to introduce functional tags in various microviridin variants yielding biotinylated, dansylated or propargylated congeners. This straightforward approach paves the way for customized protease inhibitors with built-in functionalities that can help to unravel the still elusive ecological roles and targets of this remarkable class of compounds and to foster applications based on protease inhibition.


Asunto(s)
Péptidos , Inhibidores de Serina Proteinasa , Péptidos/química , Procesamiento Proteico-Postraduccional , Péptido Hidrolasas , Lactamas , Lactonas
7.
Plant Cell Environ ; 45(3): 936-954, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34392550

RESUMEN

Soil contamination with toxic metalloids, such as arsenic, can represent a substantial human health and environmental risk. Some plants are thought to tolerate soil toxicity using root exudation, however, the nature of this response to arsenic remains largely unknown. Here, white lupin plants were exposed to arsenic in a semi-hydroponic system and their exudates were profiled using untargeted liquid chromatography-tandem mass spectrometry. Arsenic concentrations up to 1 ppm were tolerated and led to the accumulation of 12.9 µg As g-1 dry weight (DW) and 411 µg As g-1 DW in above-ground and belowground tissues, respectively. From 193 exuded metabolites, 34 were significantly differentially abundant due to 1 ppm arsenic, including depletion of glutathione disulphide and enrichment of phytochelatins and coumarins. Significant enrichment of phytochelatins in exudates of arsenic-treated plants was further confirmed using exudate sampling with strict root exclusion. The chemical tolerance toolkit in white lupin included nutrient acquisition metabolites as well as phytochelatins, the major intracellular metal-binding detoxification oligopeptides which have not been previously reported as having an extracellular role. These findings highlight the value of untargeted metabolite profiling approaches to reveal the unexpected and inform strategies to mitigate anthropogenic pollution in soils around the world.


Asunto(s)
Arsénico , Lupinus , Arsénico/metabolismo , Arsénico/toxicidad , Cumarinas , Exudados y Transudados/química , Exudados y Transudados/metabolismo , Lupinus/metabolismo , Fitoquelatinas/metabolismo , Raíces de Plantas/metabolismo , Plantas/metabolismo , Suelo/química
8.
BMC Microbiol ; 21(1): 259, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34583649

RESUMEN

BACKGROUND: Oral iron supplementation is commonly prescribed for anemia and may play an important role in the gut microbiota recovery of anemic individuals who received antibiotic treatment. This study aims to investigate the effects of iron supplementation on gut microbiota recovery after antibiotics exposure. RESULTS: Mice were subjected to oral antibiotic treatment with neomycin and metronidazole and were fed diets with different concentrations of iron. The composition of the gut microbiota was followed throughout treatment by 16S rRNA sequencing of DNA extracted from fecal samples. Gut microbiota functions were inferred using PICRUSt2, and short-chain fatty acid concentration in fecal samples was assessed by liquid-chromatography mass spectrometry. Iron supplementation after antibiotic exposure shifted the gut microbiota composition towards a Bacteroidetes phylum-dominant composition. At the genus level, the iron-supplemented diet induced an increase in the abundance of Parasutterella and Bacteroides, and a decrease of Bilophila and Akkermansia. Parasutterella excrementihominis, Bacteroides vulgatus, and Alistipes finegoldii, were more abundant with the iron excess diet. Iron-induced shifts in microbiota composition were accompanied by functional modifications, including an enhancement of the biosynthesis of primary bile acids, nitrogen metabolism, cyanoamino acid metabolism and pentose phosphate pathways. Recovery after antibiotic treatment increased propionate levels independent of luminal iron levels, whereas butyrate levels were diminished by excess iron. CONCLUSIONS: Oral iron supplementation after antibiotic therapy in mice may lead to deleterious changes in the recovery of the gut microbiota. Our results have implications on the use of oral iron supplementation after antibiotic exposure and justify further studies on alternative treatments for anemia in these settings.


Asunto(s)
Antibacterianos/efectos adversos , Bacterias/efectos de los fármacos , Suplementos Dietéticos/efectos adversos , Disbiosis/inducido químicamente , Microbioma Gastrointestinal/efectos de los fármacos , Hierro/efectos adversos , Animales , Bacterias/clasificación , Biodiversidad , Disbiosis/microbiología , Heces/microbiología , Hierro/farmacología , Ratones
9.
Odontology ; 109(3): 596-604, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33387161

RESUMEN

Secondary/persistent infections are present in teeth with previous root canal treatment, and a great variety of anaerobic microorganisms has been observed in these infections. The antibiotics prescription is occasional; however, in some cases, it is essential, particularly when the general health condition of the patient is compromised. The aims of this study were to identify the associated microorganisms in diagnosis of persistent or secondary apical periodontitis and to evaluate the susceptibility level to the antibiotics most used. Fifteen patients with persistent or secondary apical periodontitis requiring endodontic re-treatment were included. Microbiological samples were taken from the root canals and incubated in thioglycollate under anaerobic conditions. Anaerobic CDC agar (formulated by the Center for Disease Control and Prevention) was employed as a culture medium and the microorganisms were identified using the API system. The microorganisms were subjected to antibiograms with three different antibiotics. Twenty-six microorganisms were identified, the most common genus was Enterococcus (26.8%), Streptococcus (19.22%), Aerococcus (19.1%), and Clostridium (11.4%). 48% of them were susceptible to amoxicillin, with 28% of resistance. For clavulanic acid/amoxicillin, the susceptibility occurred in 32%, with 28% of resistance; and for clindamycin, the susceptibility was present in 40%, with 52% of resistance. The most frequently detected associated microorganism for secondary infections was genus Enterococcus, which exhibited high resistance to the studied antibiotics.


Asunto(s)
Cavidad Pulpar , Periodontitis Periapical , Amoxicilina , Antibacterianos/farmacología , Humanos , Periodontitis Periapical/tratamiento farmacológico , Tratamiento del Conducto Radicular
10.
Int J Mol Sci ; 21(10)2020 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-32408609

RESUMEN

The Transient Receptor Potential Vanilloid 1 (TRPV1) channel is a polymodal protein with functions widely linked to the generation of pain. Several agonists of exogenous and endogenous nature have been described for this ion channel. Nonetheless, detailed mechanisms and description of binding sites have been resolved only for a few endogenous agonists. This review focuses on summarizing discoveries made in this particular field of study and highlighting the fact that studying the molecular details of activation of the channel by different agonists can shed light on biophysical traits that had not been previously demonstrated.


Asunto(s)
Activación del Canal Iónico , Dominios Proteicos , Canales Catiónicos TRPV/química , Canales Catiónicos TRPV/metabolismo , Animales , Sitios de Unión/genética , Humanos , Ligandos , Modelos Moleculares , Unión Proteica , Canales Catiónicos TRPV/genética
11.
Environ Microbiol ; 21(7): 2440-2468, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30990927

RESUMEN

Analysis of 16S ribosomal RNA (rRNA) gene amplification data for microbial barcoding can be inaccurate across complex environmental samples. A method, ANCHOR, is presented and designed for improved species-level microbial identification using paired-end sequences directly, multiple high-complexity samples and multiple reference databases. A standard operating procedure (SOP) is reported alongside benchmarking against artificial, single sample and replicated mock data sets. The method is then directly tested using a real-world data set from surface swabs of the International Space Station (ISS). Simple mock community analysis identified 100% of the expected species and 99% of expected gene copy variants (100% identical). A replicated mock community revealed similar or better numbers of expected species than MetaAmp, DADA2, Mothur and QIIME1. Analysis of the ISS microbiome identified 714 putative unique species/strains and differential abundance analysis distinguished significant differences between the Destiny module (U.S. laboratory) and Harmony module (sleeping quarters). Harmony was remarkably dominated by human gastrointestinal tract bacteria, similar to enclosed environments on earth; however, Destiny module bacteria also derived from nonhuman microbiome carriers present on the ISS, the laboratory's research animals. ANCHOR can help substantially improve sequence resolution of 16S rRNA gene amplification data within biologically replicated environmental experiments and integrated multidatabase annotation enhances interpretation of complex, nonreference microbiomes.


Asunto(s)
ADN Bacteriano/genética , Exobiología/métodos , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Microbiología Ambiental , Microbioma Gastrointestinal , Humanos , Microbiota , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Nave Espacial , Especificidad de la Especie
12.
Cerebellum ; 18(4): 750-760, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31062284

RESUMEN

The purpose of this study is to determine the activation of the extrinsic and intrinsic apoptotic pathways in the cerebellum of rats exposed to amygdaloid electrical kindling. Western blot analyses were carried out for caspase-8 and caspase-9, Bid, Bax, and Bcl-2 in the cerebellum and immunohistochemistry of Bid, Bax, cytochrome C, and VDAC (voltage-dependent anion channels) in the cerebellar cortex of Wistar male rats with 0, 15, and 45 kindling stimulations. In the experimental group of 45 stimuli, we observed an increase in protein activation of caspase-9 and truncated Bid and Bax, in addition to a decrease in expression of pro-caspase-8 and the anti-apoptotic protein Bcl-2, determined by Western blot. Moreover, we observed a cytosolic immunopositivity for cytochrome C and a mitochondrial immunolocalization for truncated Bid and Bax in the group of 45 stimuli. In this work, we found an increase of caspase-8, a cysteine-protease that can activate caspase-3 triggering extrinsic apoptosis by signaling of death receptors. However, it also can activate the intrinsic pathway releasing Bid, which performs mitochondrial translocation of Bax, inactivating Bcl-2 and allowing the release of cytochrome C through the opening of the mitochondrial permeability transition pore, promoting the activation of caspase-9 which activates caspase-3, the main executor caspase of apoptosis. Therefore, it is concluded that there is an activation of the intrinsic and extrinsic apoptotic pathways in the cerebellum of rats exposed to the kindling model. Apoptosis signaling pathways can be analyzed as an important developing object of research about the epileptic activity. Graphical Abstract.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/genética , Apoptosis/fisiología , Cerebelo/fisiología , Excitación Neurológica , Amígdala del Cerebelo/fisiología , Animales , Proteínas Reguladoras de la Apoptosis/biosíntesis , Corteza Cerebelosa/fisiología , Electrodos Implantados , Inmunohistoquímica , Masculino , Ratas , Ratas Wistar
13.
Odontology ; 107(3): 409-417, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30758697

RESUMEN

This study aimed to identify the aerobic and anaerobic causal microorganisms of odontogenic infections and their antibiotic sensitivity. Purulent exudates were taken from patients with odontogenic infections by transdermal puncture, and aerobic and anaerobic microorganisms were identified using biochemical tests. Susceptibility to antibiotics was tested using the Kirby-Bauer method; the inhibition halos were measured according to NCCLS, and based on the results, the microorganisms were classified as susceptible, intermediate or resistant to each antibiotic. Frequencies of species and percentages of resistance were calculated. The microorganisms associated with odontogenic infections were principally anaerobic (65.3% anaerobic vs. 35.7% aerobic), and the susceptibility to antibiotics was higher in anaerobic than in aerobic microorganisms. The majority of isolated microorganisms (82%) showed susceptibility to amoxicillin/clavulanic acid. The causal agents of odontogenic infections were anaerobic microorganisms, which exhibited high resistance to antibiotics.


Asunto(s)
Antibacterianos , Anaerobiosis , Humanos , Pruebas de Sensibilidad Microbiana
14.
Plant Physiol ; 171(1): 3-24, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27002060

RESUMEN

Metatranscriptomic study of nonmodel organisms requires strategies that retain the highly resolved genetic information generated from model organisms while allowing for identification of the unexpected. A real-world biological application of phytoremediation, the field growth of 10 Salix cultivars on polluted soils, was used as an exemplar nonmodel and multifaceted crop response well-disposed to the study of gene expression. Sequence reads were assembled de novo to create 10 independent transcriptomes, a global transcriptome, and were mapped against the Salix purpurea 94006 reference genome. Annotation of assembled contigs was performed without a priori assumption of the originating organism. Global transcriptome construction from 3.03 billion paired-end reads revealed 606,880 unique contigs annotated from 1588 species, often common in all 10 cultivars. Comparisons between transcriptomic and metatranscriptomic methodologies provide clear evidence that nonnative RNA can mistakenly map to reference genomes, especially to conserved regions of common housekeeping genes, such as actin, α/ß-tubulin, and elongation factor 1-α. In Salix, Rubisco activase transcripts were down-regulated in contaminated trees across all 10 cultivars, whereas thiamine thizole synthase and CP12, a Calvin Cycle master regulator, were uniformly up-regulated. De novo assembly approaches, with unconstrained annotation, can improve data quality; care should be taken when exploring such plant genetics to reduce de facto data exclusion by mapping to a single reference genome alone. Salix gene expression patterns strongly suggest cultivar-wide alteration of specific photosynthetic apparatus and protection of the antenna complexes from oxidation damage in contaminated trees, providing an insight into common stress tolerance strategies in a real-world phytoremediation system.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Salix/genética , Contaminantes del Suelo , Estrés Fisiológico/genética , Transcriptoma , Animales , Bacterias/genética , Regulación hacia Abajo , Contaminación Ambiental , Restauración y Remediación Ambiental , Flores/genética , Hongos/genética , Perfilación de la Expresión Génica , Genes Esenciales , Genes de Plantas , Genoma de Planta , Anotación de Secuencia Molecular , Mapeo Nucleótido , Factor 1 de Elongación Peptídica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , ARN de Planta/genética , Salix/enzimología , Salix/crecimiento & desarrollo , Salix/metabolismo , Árboles/genética , Árboles/crecimiento & desarrollo , Tubulina (Proteína)
15.
Angew Chem Int Ed Engl ; 55(32): 9398-401, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27336908

RESUMEN

Microviridins are a family of ribosomally synthesized and post-translationally modified peptides with a highly unusual architecture featuring non-canonical lactone as well as lactam rings. Individual variants specifically inhibit different types of serine proteases. Here we have established an efficient in vitro reconstitution approach based on two ATP-grasp ligases that were constitutively activated using covalently attached leader peptides and a GNAT-type N-acetyltransferase. The method facilitates the efficient in vitro one-pot transformation of microviridin core peptides to mature microviridins. The engineering potential of the chemo-enzymatic technology was demonstrated for two synthetic peptide libraries that were used to screen and optimize microviridin variants targeting the serine proteases trypsin and subtilisin. Successive analysis of intermediates revealed distinct structure-activity relationships for respective target proteases.


Asunto(s)
Biblioteca de Péptidos , Péptidos Cíclicos/farmacología , Inhibidores de Serina Proteinasa/farmacología , Subtilisina/antagonistas & inhibidores , Tripsina/metabolismo , Vías Biosintéticas , Péptidos Cíclicos/biosíntesis , Péptidos Cíclicos/química , Inhibidores de Serina Proteinasa/biosíntesis , Inhibidores de Serina Proteinasa/química , Subtilisina/metabolismo
16.
BMC Plant Biol ; 15: 246, 2015 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-26459343

RESUMEN

BACKGROUND: High concentrations of petroleum hydrocarbon (PHC) pollution can be hazardous to human health and leave soils incapable of supporting agricultural crops. A cheap solution, which can help restore biodiversity and bring land back to productivity, is cultivation of high biomass yielding willow trees. However, the genetic mechanisms which allow these fast-growing trees to tolerate PHCs are as yet unclear. METHODS: Salix purpurea 'Fish Creek' trees were pot-grown in soil from a former petroleum refinery, either lacking or enriched with C10-C50 PHCs. De novo assembled transcriptomes were compared between tree organs and impartially annotated without a priori constraint to any organism. RESULTS: Over 45% of differentially expressed genes originated from foreign organisms, the majority from the two-spotted spidermite, Tetranychus urticae. Over 99% of T. urticae transcripts were differentially expressed with greater abundance in non-contaminated trees. Plant transcripts involved in the polypropanoid pathway, including phenylalanine ammonia-lyase (PAL), had greater expression in contaminated trees whereas most resistance genes showed higher expression in non-contaminated trees. CONCLUSIONS: The impartial approach to annotation of the de novo transcriptomes, allowing for the possibility for multiple species identification, was essential for interpretation of the crop's response treatment. The meta-transcriptomic pattern of expression suggests a cross-tolerance mechanism whereby abiotic stress resistance systems provide improved biotic resistance. These findings highlight a valuable but complex biotic and abiotic stress response to real-world, multidimensional contamination which could, in part, help explain why crops such as willow can produce uniquely high biomass yields on challenging marginal land.


Asunto(s)
Adaptación Fisiológica/genética , Hidrocarburos/toxicidad , Petróleo/toxicidad , Salix/genética , Contaminantes del Suelo/toxicidad , Transcriptoma/genética , Adaptación Fisiológica/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Herbivoria/efectos de los fármacos , Herbivoria/genética , Anotación de Secuencia Molecular , Propanoles/metabolismo , Salix/efectos de los fármacos , Salix/crecimiento & desarrollo , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética , Transcriptoma/efectos de los fármacos , Árboles/efectos de los fármacos , Árboles/genética , Árboles/crecimiento & desarrollo
17.
Front Nutr ; 11: 1341777, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529196

RESUMEN

Introduction: Ingestion of human milk (HM) is identified as a significant factor associated with early infant gut microbial colonization, which has been associated with infant health and development. Maternal diet has been associated with the HM microbiome (HMM). However, a few studies have explored the associations among maternal diet, HMM, and infant growth during the first 6 months of lactation. Methods: For this cross-sectional study, Mam-Mayan mother-infant dyads (n = 64) were recruited from 8 rural communities in the Western Highlands of Guatemala at two stages of lactation: early (6-46 days postpartum, n = 29) or late (109-184 days postpartum, n = 35). Recruited mothers had vaginally delivered singleton births, had no subclinical mastitis or antibiotic treatments, and breastfed their infants. Data collected at both stages of lactation included two 24-h recalls, milk samples, and infant growth status indicators: head-circumference-for-age-z-score (HCAZ), length-for-age-z-score (LAZ), and weight-for-age-z-score (WAZ). Infants were divided into subgroups: normal weight (WAZ ≥ -1SD) and mildly underweight (WAZ < -1SD), non-stunted (LAZ ≥ -1.5SD) and mildly stunted (LAZ < -1.5SD), and normal head-circumference (HCAZ ≥ -1SD) and smaller head-circumference (HCAZ < -1SD). HMM was identified using 16S rRNA gene sequencing; amplicon analysis was performed with the high-resolution ANCHOR pipeline, and DESeq2 identified the differentially abundant (DA) HMM at the species-level between infant growth groups (FDR < 0.05) in both early and late lactation. Results: Using both cluster and univariate analyses, we identified (a) positive correlations between infant growth clusters and maternal dietary clusters, (b) both positive and negative associations among maternal macronutrient and micronutrient intakes with the HMM at the species level and (c) distinct correlations between HMM DA taxa with maternal nutrient intakes and infant z-scores that differed between breast-fed infants experiencing growth faltering and normal growth in early and late lactation. Conclusion: Collectively, these findings provide important evidence of the potential influence of maternal diet on the early-life growth of breastfed infants via modulation of the HMM.

18.
Sci Total Environ ; 926: 171854, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38522550

RESUMEN

Reducing the environmental impact of Canadian field crop agriculture, including the reliance on conventional synthesised fertilisers, are key societal targets for establishing long-term sustainable practices. Municipal biosolids (MSB) are an abundant, residual organic material, rich in phosphate, nitrogen and other oligo-nutrients, that could be used in conjunction with conventional fertilisers to decrease their use. Though MBS have previously been shown to be an effective fertiliser substitute for different crops, including corn and soybean, there remain key knowledge gaps concerning the impact of MBS on the resident soil bacterial communities in agro-ecosystems. We hypothesised that the MBS fertiliser amendment would not significantly impact the structure or function of the soil bacterial communities, nor contribute to the spread of human pathogenic bacteria, in corn or soybean agricultural systems. In field experiments, fertiliser regimes for both crops were amended with MBS, and compared to corn and soybean plots with standard fertiliser treatments. We repeated this across four different agricultural sites in Quebec, over 2021 and 2022. We sampled MBS-treated, and untreated soils, and identified the composition of the soil bacterial communities via 16S rRNA metabarcoding. We found no indication that the MBS fertiliser amendment altered the structure of the soil bacterial communities, but rather that the soil type and crop identities were the most significant factors in structuring the bacterial communities. Moreover, there was no evidence that the MBS-treated soils were enriched in potential human bacterial pathogens over the two years of our study. Our analysis indicates that not only can MBS function as substitutes for conventional, synthesised fertilisers, but that they also do not disrupt the structure of the resident soil bacterial communities in the short term. Finally, we suggest that the use of MBS in agro-ecosystems poses no greater concern to the public than existing soil bacterial communities. This highlights the significant role MBS could potentially have in reducing the use of conventional industrial fertilisers and improving agricultural production, without risking environmental contamination.


Asunto(s)
Fertilizantes , Suelo , Humanos , Suelo/química , Fertilizantes/análisis , Biosólidos , Ecosistema , ARN Ribosómico 16S , Canadá , Agricultura , Bacterias , Microbiología del Suelo
19.
Heliyon ; 10(5): e27226, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38463774

RESUMEN

Cuticular waxes of plants impart tolerance to many forms of environmental stress and help shed dangerous human pathogens on edible plant parts. Although the chemical composition of waxes on a wide variety of important crops has been described, a detailed wax compositional analysis has yet to be reported for lettuce (Lactuca sativa L.), one of the most widely consumed vegetables. We present herein the leaf wax content and composition of 12 genetically diverse lettuce cultivars sampled across five time points during their vegetative growth phase in the field. Mean total leaf wax amounts across all cultivars varied little over 28 days of vegetative growth, except for a notable decrease in total waxes following a major precipitation event, presumably due to wax degradation from wind and rain. All lettuce cultivars were found to contain a unique wax composition highly enriched in 22- and 24-carbon length 1-alcohols (docosanol and tetracosanol, respectively). In our report, the dominance of these shorter chain length 1-alcohols as wax constituents represents a relatively rare phenotype in plants. The ecological significance of these dominant and relatively short 1-alcohols is still unknown. Although waxes have been a target for improvement of various crops, no such work has been reported for lettuce. This study lays the groundwork for future research that aims to integrate cuticular wax characteristics of field grown plants into the larger context of lettuce breeding and cultivar development.

20.
Plast Reconstr Surg Glob Open ; 12(3): e5695, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38525493

RESUMEN

Background: The rejuvenation and restoration of a well-defined jawline contour are crucial for enhancing facial aesthetics in both men and women. Within the jawline aesthetic unit (mandibular angle), the masseter muscle plays a significant role, as it is responsible for mandibular masticatory movements. We propose a new approach using ultrasound-guided intramuscular fat transfer to enhance the mandibular angle and jawline. Methods: The multicenter study included 20 patients from three countries (Peru, Brazil, and Mexico). After fat harvesting, the ultrasound-guided masseteric fat transfer was performed with a 1.5-mm Viaro cannula from an incision beneath the ear lobule. The fat was then injected intramuscularly into the masseter at each side of the mandibular angle. Results: Masseter ultrasound-guided fat transfer was performed on 10 men and 10 women between 2021 and 2022. The patients had a mean age of 34.4 ±â€…6.39 years and a mean body mass index of 22.39 ±â€…2.59 kg per m2. The mean injected volume was 5.83 mL and 5.58 mL on the right and left sides, respectively. Muscle thickness increased in patients immediately postsurgery, but decreased after 1 month. The muscle remained significantly thicker on each side than the presurgery measurements in patients regardless of gender (both P < 0.0001). Conclusions: Ultrasound-guided intramuscular fat transfer is a safe and reproducible technique for enhancing the jawline contour at the mandibular angle. We believe that it could be a more durable solution than other procedures, although further evaluation of long-term results is necessary.

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