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1.
World J Microbiol Biotechnol ; 36(3): 50, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32157464

RESUMEN

Despite the deep knowledge of the honey bee (Apis mellifera) gut microbiome, information on the microbial communities of other hive components is still scarce. Propolis originates from a natural resinous mixture that honeybees collect from different plants sources and modify; it is used mainly to ensure the hygiene of the hive. By virtue of its antimicrobial properties, propolis has been considered relatively aseptic, yet its ability to harbor microorganisms has not been previously investigated. In this study we report the first description of the diversity of the microbial community of propolis by both targeted-metagenomics analysis and cultivation. We demonstrated that propolis hosts a variety of microbial strains belonging to taxa already described in other hive components. Some of them are cultivable in standard laboratory conditions, and show metabolic characteristics compatible with their persistence in different physiological states inside propolis. Isolated bacteria produce antimicrobials against Gram-negative and Gram-positive bacteria, and entomopathogenic fungi, with different spectra of inhibition. Metagenomics analysis shows the presence of bacteria and fungi with great potential to outcompete potentially harmful microorganisms. These findings suggest that the characterized microbiota could contribute to the overall antimicrobial properties of propolis and to its ecological role as "disinfectant" within the hive.


Asunto(s)
Bacterias/clasificación , Hongos/clasificación , Microbiota , Própolis/farmacología , Animales , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Bacterias/aislamiento & purificación , Abejas , ADN Ribosómico/genética , Hongos/efectos de los fármacos , Hongos/aislamiento & purificación , Microbioma Gastrointestinal , Pruebas de Sensibilidad Microbiana , Microbiota/efectos de los fármacos , Filogenia
2.
Environ Monit Assess ; 192(4): 238, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32173770

RESUMEN

The potential threat of both metals and antibiotics to the environment and human health has raised significant concerns in the last decade. Metal-resistant and antibiotic-resistant bacteria are found in most environments, including water, and the risk posed to humans and animals due to the spread of antibiotic-resistant bacteria and antibiotic-resistant genes in the environment is increasing. Bacteria have developed the ability to tolerate metals even at notable concentrations. This ability tends to favor the selection of antibiotic-resistant strains, even in pristine water environments, with the potential risk of spreading this resistance to human pathogens. In this mini-review, we focus on investigations performed in marine and freshwater environments worldwide, highlighting the presence of co-resistance to metals and antibiotics.


Asunto(s)
Antibacterianos , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana , Metales/farmacología , Animales , Monitoreo del Ambiente , Humanos
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(2): 104-110, 2020 Feb 09.
Artículo en Chino | MEDLINE | ID: mdl-32074671

RESUMEN

Objective: To investigate the antibacterial properties and the osteoblast-compatibility of chlorhexidine (CHX)-modified porous titanium. Methods: Smooth pure titanium specimen with diameter of 10.0 mm and thickness of 1.5 mm treated with alkali heat method were set as control group. Those with covalent conjugation of aminosilane were set as silane group, and those with CHX grafted by glutaraldehyde were set as CHX group. Scanning electron microscope (SEM) was used to observe the surface morphology and element compositions were detected by X-ray photoelectron spectroscopy. Hydrophilicity was analyzed by surface water contact angle test (n=6), while surface amino/imine groups quantification were performed through acid orangeⅡ(n=5) and the CHX was quantified by optical densitometric method (n=5). Live/dead bacterial staining, the morphology of adherent bacteria by SEM, plate counting method and inhibition zone method were executed to evaluate the antibacterial property of the samples. Osteoblast compatibility was evaluated by methyl thiazolyl tetrazolium. Cell-bacterial co-culture was conducted to evaluated the cell viability on the samples under the circumstance with bacteria. Results: After CHX grafting, pores on the titanium surface were decreased, while the atom ratio of C, N, Cl increased and the water contact angle decreased to 37.5°±4.0°. The density of CHX on the surface was (5.07±0.39) µg/cm(2). The results of live/dead bacterial staining and the morphology of adherent bacteria showed that only little dead bacterial (bacterial wall rupture) adherent on the surface of CHX group, which proved that the modified surface could inhibit bacteria adhesion and even destroyed bacteria; the plate counting displayed sporadic colonies and a transparent inhibition zone could be observed, which demonstrated that CHX group could suppress bacteria multiplication from surrounding environment. When incubating for 1 and 3 days, the cell viability of CHX group showed no significant difference from that of control group (P>0.05) ; when incubating for 5 days, the value of cell viability of CHX group was 0.547±0.087, and this was significantly lower than that of the control group (0.751±0.056) (P<0.05), demonstrating a slight inhibition of cell proliferation by CHX. The results of bacteria-cell co-culture for 3 days showed that a mass of bacteria adhered on the surface of the control group while considerable cells adhered on the surface of CHX group and exhibited a good shape. Conclusions: Porous titanium surface grafted by CHX showed an excellent antibacterial properties and allowed cell adhesion in bacterial circumstance, providing immediate implantation options for patients with bad oral health.


Asunto(s)
Antibacterianos/farmacología , Clorhexidina/farmacología , Nanoporos , Osteoblastos/efectos de los fármacos , Titanio/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Células Cultivadas , Humanos , Propiedades de Superficie
4.
Medicine (Baltimore) ; 99(7): e18570, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32049777

RESUMEN

Acute conjunctivitis is inflammation of conjunctiva of less than 3 to 4 weeks duration, characterized by cellular infiltration and exudation. It may also result into corneal, lid or orbital involvement which may lead to various complications.A hospital based prospective study was conducted in Assam Medical College and Hospital with 110 culture proven acute bacterial conjunctivitis cases. Primary objective was to evaluate the bacteriological pattern and secondary objectives were to evaluate seasonal variation, association of different organisms with various complications and antibiotic sensitivity pattern of the isolates.Maximum frequency of bacterial conjunctivitis observed from May to September. SA was the predominant organism isolated throughout the year (32.1%). Commonest single organism isolates were SE (26.1%) and SA (21.6%). True membrane formation was significantly associated with CD (P < .05), whereas pseudo-membrane formation was associated with SA and STBH isolation (P < .05). Isolation of SE, SA, and PA was associated with corneal involvement (P < .05). Lid involvement was seen with SA and Diphtheroid, whereas SP isolation was associated with concomitant dacryocystitis (P < .05). All the major organisms were (SE, SA, D, STBH, SP) highly sensitive to amino-glycosides, cephalosporins, chloromphenicol, vancomycin and linezolid, whereas high level of resistance was seen towards fluroquinolones (ciprofloxacin and moxifloxacin).All acute bacterial conjunctivitis cases don't require antibiotic therapy. In case if required, periodical culture and sensitivity may guide initial pre-emptive antibiotic therapy. Further choice of antibiotic should be govern by culture and sensitivity status.


Asunto(s)
Antibacterianos/farmacología , Bacterias/aislamiento & purificación , Conjuntivitis Bacteriana/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Bacterias/clasificación , Bacterias/efectos de los fármacos , Niño , Preescolar , Conjuntivitis Bacteriana/tratamiento farmacológico , Estudios Transversales , Farmacorresistencia Bacteriana , Femenino , Humanos , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos , Centros de Atención Terciaria , Adulto Joven
5.
Environ Monit Assess ; 192(3): 176, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-32062749

RESUMEN

Interactive effects of mixtures of pesticides on bacteria are rarely investigated. The aim of this study was to investigate the cumulative, synergistic, and antagonistic effects of four widely used agricultural pesticides including deltamethrin, diazinon, chlorpyrifos, and 2,4-dichlorophenoxyacetic acid (2,4-D) on Pseudomonas, Aeromonas, and Bacillus bacteria. The reduction of alamar blue, as an indicator of bacterial activity, was measured using a spectrophotometer at 600-nm wavelength. Data were analyzed using SPSS 24.0 software. The binary mixtures of pesticides had mainly antagonistic and additive effects, but quadruple mixtures of pesticides had synergistic effects on all of the three bacterial species. In the mixtures of pesticides, increasing the number of compounds leads to more synergistic effects.


Asunto(s)
Bacterias , Cloropirifos , Monitoreo del Ambiente , Plaguicidas , Agricultura , Bacterias/efectos de los fármacos , Plaguicidas/toxicidad
6.
J Agric Food Chem ; 68(3): 779-787, 2020 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-31894986

RESUMEN

The chain length of fructan determines its different physiological effects. This study is to explore the effects of low-performance inulin [LPI, degree of polymerization (DP) ≤ 9] and high-performance inulin (HPI, DP ≥ 23) on obesity-associated liver injury of high-fat diet (HFD) feeding mice and its underlying mechanism. Eight weeks of supplementation of C57BL/6J mice with HPI, relative to LPI (p < 0.05), caused the more efficient improvement against the HFD-induced liver insulin resistance through activating IRS1/PI3K/Akt pathway and reduced protein expressions of inflammatory factors nuclear factor-kappaB (NF-κB) and interleukin-6 (IL-6) in the liver. HPI exhibited the more positive effects on liver steatosis by inhibiting acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS), and sterol regulatory element binding protein 1 (SREBP1) in comparison with LPI (p < 0.05). HPI also increased acetic acid, propionic acid, and butyric acid levels in the colon of HFD-fed mice (p < 0.05). Compared to LPI, HPI feeding of HFD-fed mice led to the more effective decrease in the Firmicutes abundance from 72.1% to 34.5%, but a more significant increase in the Bacteroidetes population from 19.8 to 57.1% at the phyla level, and increased the abundance of Barnesiella, Bacteroides, and Parabacteroides at the genus level (p < 0.05). Depending on DP, HPI exerts the more positive regulation on liver injury and gut microbiota dysfunction than LPI.


Asunto(s)
Disbiosis/tratamiento farmacológico , Microbioma Gastrointestinal/efectos de los fármacos , Inulina/administración & dosificación , Inulina/química , Hígado/lesiones , Obesidad/tratamiento farmacológico , Animales , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/aislamiento & purificación , Dieta Alta en Grasa/efectos adversos , Suplementos Dietéticos/análisis , Disbiosis/genética , Disbiosis/metabolismo , Disbiosis/microbiología , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , FN-kappa B/genética , FN-kappa B/metabolismo , Obesidad/genética , Obesidad/metabolismo , Obesidad/microbiología , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Polimerizacion
7.
J Agric Food Chem ; 68(6): 1621-1633, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-31967468

RESUMEN

Collagen peptides can promote wound healing and are closely related to microbiome colonization. We investigated the relationship among collagen peptides, wound healing, and wound microflora colonization by administering the murine wound model with Salmo salar skin collagen peptides (Ss-SCPs) and Tilapia nilotica skin collagen peptides (Tn-SCPs). We analyzed the vascular endothelial growth factor (VEGF), fibroblast growth factors (ß-FGF), pattern recognition receptor (NOD2), antimicrobial peptides (ß-defence14, BD14), proinflammatory (TNF-α, IL-6, and IL-8) and anti-inflammatory (IL-10) cytokines, macrophages, neutrophil infiltration levels, and microbial communities in the rat wound. The healing rates of the Ss-SCP- and Tn-SCP-treated groups were significantly accelerated, associated with decreased TNF-α, IL-6, and IL-8 and upregulated BD14, NOD2, IL-10, VEGF, and ß-FGF. Accelerated healing in the collagen peptide group shows that the wound microflora such as Leuconostoc, Enterococcus, and Bacillus have a positive effect on wound healing (P < 0.01). Other microbiome species such as Stenotrophomonas, Bradyrhizobium, Sphingomonas, and Phyllobacterium had a negative influence and decreased colonization (P < 0.01). Altogether, these studies show that collagen peptide could upregulate wound NOD2 and BD14, which were implicated in microflora colonization regulation in the wound tissue and promoted wound healing by controlling the inflammatory reaction and increasing wound angiogenesis and collagen deposition.


Asunto(s)
Colágeno/química , Proteínas de Peces/química , Microbiota/efectos de los fármacos , Proteína Adaptadora de Señalización NOD2/genética , Péptidos/administración & dosificación , Piel/química , Heridas y Traumatismos/fisiopatología , beta-Defensinas/genética , Administración Cutánea , Animales , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/aislamiento & purificación , Cíclidos , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/inmunología , Humanos , Interleucina-10/genética , Interleucina-10/inmunología , Masculino , Ratones , Proteína Adaptadora de Señalización NOD2/inmunología , Péptidos/química , Ratas , Ratas Sprague-Dawley , Salmo salar , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/inmunología , Cicatrización de Heridas/efectos de los fármacos , Heridas y Traumatismos/tratamiento farmacológico , Heridas y Traumatismos/inmunología , Heridas y Traumatismos/microbiología , beta-Defensinas/inmunología
8.
J Agric Food Chem ; 68(8): 2457-2466, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-31995379

RESUMEN

The influence of the rhizosphere on the abundance and diversity of antibiotic resistance genes (ARGs) has been recognized but there is a lack of consensus because of broad ranges of plant species and antibiotic concentrations across different habitats and the elusive underlying mechanisms. Here, we profiled antibiotic concentrations and resistomes in the rhizosphere and bulk soils by cultivating 10 types of crops in manure-amended agricultural soils. Rhizosphere effects altered the antibiotic resistome structure, significantly increased the absolute abundance of the antibiotic resistome, and decreased their relative abundance, contrasting previous studies. Such plantation-driven variation in ARGs resulted from the boost of bacterial lineages with negative relationships with ARGs and the constraint of the potential ARG-hosts in the rhizosphere of plants cultivated in soils with low antibiotic concentrations as the selective pressure. This mechanism is not reported previously and deepens our understanding about the rhizosphere effects on ARGs.


Asunto(s)
Antibacterianos/análisis , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana , Suelo/química , Agricultura , Bacterias/genética , Bacterias/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Productos Agrícolas/crecimiento & desarrollo , Rizosfera , Microbiología del Suelo
9.
Chem Commun (Camb) ; 56(10): 1464-1480, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-31967621

RESUMEN

This review discusses the advantages of using luminescent d6-transition-metal complexes as cell probes for optical microscopy. In particular it focusses on the Thomas group's use of specific complexes as "building blocks" toward the construction of biomolecular binding substrates, with DNA being a particular target. Using this approach, a range of new imaging probes for conventional optical microscopy, nanoscopy and transmission electron microscopy have been identified. Through selection of specific metal centres and by substitution of coordinated ligands we illustrate how new chemotherapeutics, photo-therapeutics, and theranostics have been identified and developed from the original architectures.


Asunto(s)
Complejos de Coordinación/química , ADN/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Apoptosis/efectos de los fármacos , Bacterias/efectos de los fármacos , Medios de Contraste/química , Medios de Contraste/metabolismo , Complejos de Coordinación/metabolismo , Complejos de Coordinación/toxicidad , ADN/metabolismo , Humanos , Sondas Moleculares/química , Sondas Moleculares/metabolismo , Nanomedicina Teranóstica
10.
BMC Infect Dis ; 20(1): 8, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-31906848

RESUMEN

BACKGROUND: There have been no systematic studies of microbiological differences before and after antibiotics treatment. The aim of this study was to evaluate the effect of prior receipt of antibiotics on the microorganism distribution. METHODS: A retrospective, observational cohort study was conducted in a 3200-bed tertiary, referral, teaching hospital in eastern China. During a 2-year period, all hospitalized patients treated with antimicrobial agents were enrolled in this study. Among 48,692 patients evaluated, the 27,792 (57.1%) who were sampled within 2 days before or after administration of the first dose of antimicrobial agents were included. Distribution of clinical specimens and the microorganism were compared between before and after antibiotic drug treatment groups. RESULTS: Compared to specimens taken after antibiotics exposure, specimens taken before antibiotics exposure had a higher proportion of blood and urine specimens and a higher culture positive rate (all P < 0.001). Higher percentages of Staphylococcus aureus (9.9% vs. 8.5%, P = 0.041), non-fermenting bacteria (27.7% vs. 19.9%, P < 0.001), and fungi (8.4% vs. 4.0%, P < 0.001) were isolated from the group after antibiotics exposure, while the percentages of Streptococcus spp. (4.8% vs. 2.7%, P < 0.001), Haemophilus influenzae (2.3% vs. 0.8%, P < 0.001), and Moraxella catarrhalis (0.7% vs. 0.1%, P < 0.001) were higher in the group before antibiotics exposure. Further analysis found significant differences of microbes derived from respiratory secretions, blood or urine samples. We found, after antibiotics exposure, the separation rate of non-fermenting bacteria was significantly increased (all P < 0.05), and the separation rate of Candida spp. was higher, with statistical significance in airway secretion and urine samples (both P < 0.05), but the separation rate of Staphylococcus aureus among the three groups was not affected by antibiotics. In addition, the isolation rate of Streptococcus spp. in blood and urine samples decreased significantly (both P < 0.05) after antibiotics exposure. Interestingly, no statistical difference was found for microbes isolated from body fluid specimens between the two groups. CONCLUSIONS: The outcome revealed that antibiotic-insensitive organisms such as non-fermentative bacteria and fungi were more frequently isolated after antibiotics exposure. However, this trend might be specimen dependent and was not obvious in body fluid specimens.


Asunto(s)
Antibacterianos/uso terapéutico , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Anciano , Antibacterianos/efectos adversos , Antibacterianos/farmacología , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , China , Femenino , Hongos/clasificación , Hongos/efectos de los fármacos , Hongos/crecimiento & desarrollo , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
11.
Zool Res ; 41(1): 20-31, 2020 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-31930784

RESUMEN

There is a growing appreciation for the specific health benefits conferred by commensal microbiota on their hosts. Clinical microbiota analysis and animal studies in germ-free or antibiotic-treated mice have been crucial for improving our understanding of the role of the microbiome on the host mucosal surface; however, studies on the mechanisms involved in microbiome-host interactions remain limited to small animal models. Here, we demonstrated that rhesus monkeys under short-term broad-spectrum antibiotic treatment could be used as a model to study the gut mucosal host-microbiome niche and immune balance with steady health status. Results showed that the diversity and community structure of the gut commensal bacteria in rhesus monkeys were both disrupted after antibiotic treatment. Furthermore, the 16S rDNA amplicon sequencing results indicated that Escherichia-Shigella were predominant in stool samples 9 d of treatment, and the abundances of bacterial functional genes and predicted KEGG pathways were significantly changed. In addition to inducing aberrant morphology of small intestinal villi, the depletion of gut commensal bacteria led to increased proportions of CD3 + T, CD4 + T, and CD16 + NK cells in peripheral blood mononuclear cells (PBMCs), but decreased numbers of Treg and CD20 + B cells. The transcriptome of PBMCs from antibiotic-treated monkeys showed that the immune balance was affected by modulation of the expression of many functional genes, including IL-13, VCAM1, and LGR4.


Asunto(s)
Disbiosis/inmunología , Microbioma Gastrointestinal , Intestinos/anatomía & histología , Macaca mulatta/microbiología , Animales , Antibacterianos/farmacología , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , ADN Bacteriano/genética , Heces/microbiología , Intestinos/microbiología , Masculino
12.
J Med Microbiol ; 69(2): 298-308, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31976854

RESUMEN

Introduction. Periodontitis is among the most widespread oral bacterial diseases affecting 15-20% of the world population.Aim. This study aimed to develop dental floss impregnated with povidone-iodine (PVP-I) as an antimicrobial delivery system against periodontopathogenic bacteria in a planktonic form and within biofilms.Methods. Identical lengths of dental floss impregnated with PVP-I formulations were placed on agar along with previously grown periodontal pathogens. The bioactivity of the dental floss was investigated by response-surface methodology. In order to explore the antibacterial activity of the selected formulation and the potential application in the prevention and treatment of plaque-caused diseases such as periodontitis and caries, the antibacterial and anti-biofilm activity of the selected PVP-I formulation against pathogenic bacteria were investigated.Results. The results indicated that the coating formulation containing Eudragit L-100 2.90 %, PVP-I 24.58 % and PEG 400 3.73 % had antimicrobial activity for all pathogens. The mechanism of this formulation involved disruption of bacterial cell membranes. Moreover, this formulation inhibited the formation of oral pathogenic biofilms.Conclusion. It was concluded that Eudragit L-100 and PVP-I-coated dental floss represented a potential therapeutic agent to prevent periodontal diseases and dental caries and exhibited non-toxicity to periodontal ligament cells.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Periodontitis/prevención & control , Ácidos Polimetacrílicos/química , Povidona Yodada/farmacología , Antibacterianos/química , Bacterias/crecimiento & desarrollo , Dispositivos para el Autocuidado Bucal , Sistemas de Liberación de Medicamentos , Humanos , Periodontitis/microbiología , Povidona Yodada/química
13.
J Agric Food Chem ; 68(5): 1226-1236, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31922739

RESUMEN

As a substitute for methyl bromide, effects of allyl isothiocyanate (AITC) on nontarget microorganisms in soil are poorly understood. This study measured the half-life of AITC in the soil as well as its effects on the soil substrate-induced respiration (SIR) and on communities of soil bacteria and fungi. The results showed that AITC had a short half-life and a short-term inhibition of SIR; high-throughput sequencing analysis showed that AITC had less effect on bacterial than fungal communities. Fumigation reduced the diversity of soil bacteria temporarily, but stimulated the diversity of soil fungi in the long-term and significantly changed the structure of the fungal community. Following AITC fumigation there were significant increases in the relative abundance of probiotics such as Sphingomonas, Streptomyces, Hypocreales, Acremonium, Aspergillus, and Pseudallescheria that help to control plant diseases. Our study provided useful information for assessing the ecological safety of AITC.


Asunto(s)
Bacterias/efectos de los fármacos , Hongos/efectos de los fármacos , Isotiocianatos/farmacología , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodiversidad , Fumigación , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Isotiocianatos/química , Lycopersicon esculentum/crecimiento & desarrollo , Suelo/química
14.
Chem Biodivers ; 17(1): e1900496, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31909551

RESUMEN

The genus Lavandula is known for its different uses in traditional medicine. This study is interested in the chemical composition of Lavandulapedunculata subsp.atlantica (Braun-Blanq.) Romo as well as evaluating its antibacterial potential against multi-resistant strains. The analysis of Lavandulaatlantica essential oil (LAEO) allows the identification of 47 components representing 93.6 % of all identified. The main constituent of LAEO was camphor (50.4 %), followed by fenchone (14.1 %) and camphene (5.6 %). The antibacterial assays revealed that LAEO was active against all the studied bacteria. A preliminary study of the relationship between certain terpenoids and antibacterial activity was also carried out in order to note the compound(s) that are responsible for LAEO's antibacterial activity. This study showed that the activity of the essential oil may be due to the presence of certain minor compounds such as carvone, considering the presence of the synergistic effect between the essential oil.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Lavandula/química , Aceites Volátiles/farmacología , Terpenos/farmacología , Antibacterianos/análisis , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/análisis , Relación Estructura-Actividad , Terpenos/análisis
15.
Appl Microbiol Biotechnol ; 104(5): 1955-1976, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31970432

RESUMEN

Aminoglycosides are one of the common classes of antibiotics that have been widely used for treating infections caused by pathogenic bacteria. The mechanism of bactericidal action by aminoglycosides is well-known, by which it terminates the cytoplasmic protein synthesis. However, the potentials of aminoglycosides become hindered when facing the evolution of bacterial resistance mechanisms. Among multiple resistance mechanisms displayed by bacteria against antibiotics, the formation of biofilm is the mechanism that provides a barrier for antibiotics to reach the cellular level. Bacteria present in the biofilm also get protection against the impact of host immune responses, harsh environmental conditions, and other antimicrobial treatments. Hence, with the multifaceted resistance developed by biofilm-forming pathogenic bacteria, antibiotics are therefore discontinued for further applications. However, the recent research developed several alternative strategies such as optimization of the active concentration, modification of the environmental conditions, modification of the chemical structure, combinatorial application with other active agents, and formulation with biocompatible carrier materials to revitalize and exploit the new potential of aminoglycosides. The present review article describes the above mentioned multiple approaches and possible mechanisms for the application of aminoglycosides to treat biofilm-associated infections.


Asunto(s)
Aminoglicósidos/farmacología , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Adyuvantes Farmacéuticos/química , Adyuvantes Farmacéuticos/farmacología , Adyuvantes Farmacéuticos/uso terapéutico , Aminoglicósidos/química , Aminoglicósidos/uso terapéutico , Antibacterianos/química , Antibacterianos/uso terapéutico , Bacterias/crecimiento & desarrollo , Bacterias/patogenicidad , Infecciones Bacterianas/tratamiento farmacológico , Biopelículas/crecimiento & desarrollo , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Portadores de Fármacos/uso terapéutico , Farmacorresistencia Bacteriana , Quimioterapia Combinada , Humanos , Factores de Virulencia/metabolismo
16.
Chem Pharm Bull (Tokyo) ; 68(1): 46-57, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31902901

RESUMEN

Over the past decade, a number of new 1,4-naphthoquinones have been isolated from natural sources and new 1,4-naphthoquinones with diverse structural features have been synthesized. Cardioprotective, anti-ischemic, hepatoprotective, neuroprotective and some other new properties were found for these compounds; their role in protecting against neurodegenerative diseases has been established. Their anti-inflammatory, antimicrobial and antitumor activities have been studied in more detail; new, previously unknown intracellular molecular targets and mechanisms of action have been discovered. Some compounds of this class are already being used as a medicinal drugs and some substances can be used as biochemical tools and probes for non-invasive detection of pathological areas in cells and tissues in myocardial infarction and neurodegenerative diseases using modern molecular imaging techniques.


Asunto(s)
Antiinfecciosos/química , Antiinflamatorios/química , Naftoquinonas/química , Sustancias Protectoras/química , Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Bacterias/efectos de los fármacos , Citocinas/metabolismo , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Naftoquinonas/farmacología , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Trypanosoma/efectos de los fármacos
17.
Anticancer Res ; 40(1): 551-556, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31892611

RESUMEN

BACKGROUND/AIM: To investigate the effects of vitamin D3 supplementation on gut microbiota. PATIENTS AND METHODS: Twenty adults with vitamin D insufficiency/deficiency [25(OH)D <30 ng/ml] were enrolled and given 600, 4,000 or 10,000 IUs/day of oral vitamin D3 Stool samples were collected at baseline and 8 weeks for identifying gut microbiota using 16S rRNA gene amplification and sequencing. RESULTS: Baseline serum 25(OH)D was associated with increased relative abundance of Akkermansia and decreased relative abundance of Porphyromonas (p<0.05). After the intervention, we observed a dose-dependent increase in relative abundance of Bacteroides with a significant difference between the 600 IUs and the 10,000 IUs groups (p=0.027), and Parabacteroides with a significant difference between the 600 IUs and the 4,000 IUs groups (p=0.039). CONCLUSION: Increased serum 25(OH)D was associated with increased beneficial bacteria and decreased pathogenic bacteria. A dose-dependent increase in bacteria associated with decreased inflammatory bowel disease activity was observed after vitamin D3 supplementation.


Asunto(s)
Colecalciferol/administración & dosificación , Colecalciferol/farmacología , Suplementos Dietéticos , Microbioma Gastrointestinal/efectos de los fármacos , Administración Oral , Adulto , Bacterias/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Humanos
18.
Fitoterapia ; 140: 104406, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31698061

RESUMEN

One new quinoline alkaloid (1), two new bisabolane-type sesquiterpene derivatives (2 and 3), and a new natural product (4) along with ten known compounds (514) were isolated from the deep sea-derived fungus Aspergillus sp. SCSIO06786 which cultured on solid rice medium. Three new structures were elucidated by analysis of 1D/2D NMR data and HR-ESI-MS. The absolute configurations of 2 and 3 were established by comparison of the experimental and reported ECD values. Compounds 11-13 exhibited moderate selective inhibitory activities against the tested pathogenic bacteria with MIC values among 3.13-12.5 µg/mL.


Asunto(s)
Alcaloides/aislamiento & purificación , Aspergillus/química , Quinolinas/aislamiento & purificación , Agua de Mar/microbiología , Sesquiterpenos/aislamiento & purificación , Alcaloides/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Sedimentos Geológicos/microbiología , Océano Índico , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Quinolinas/farmacología , Sesquiterpenos/farmacología
19.
Chemosphere ; 242: 125163, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31677518

RESUMEN

The use of fungicides bears the risk of many undesirable outcomes that are manifested in, among other things, changes in the structure and activity of microorganisms. This study aimed at determining the effect of a Helicur 250 EW preparation, used to protect crops against fungal diseases, on the microbiological and biochemical activity of soil and on the development of Horderum vulgare L. The fungicide was sprayed on leaves of spring barley in the following doses (per active substance, i.e. tebuconazole, TEB): 0.046, 0.093, 0.139, 1.395, and 2.790 mg TEB plant-1. The following indices were analyzed in the study: index of microorganisms resistance (RS) to the effects of fungicide, microorganisms colony development index (CD), microorganisms ecophysiological diversity index (EP), genetic diversity of bacteria, enzymatic activity, and effect of the fungicide on spring barley development (IFH). The most susceptible to the effects of the fungicide turned out to be fungi. The metagenomic analysis demonstrated that the bacterial community differed in terms of structure and percentage contribution in the soil exposed to the fungicide from the control soil even at the Phylum level. However, Proteobacteria appeared to be the prevailing taxon in both soils. Bacillus arabhattai, B. soli, and B. simplex occurred exclusively in the control soil, whereas Ramlibacter tataounensis, Azospirillum palatum, and Kaistobacter terrae - exclusively in the soil contaminated with the fungicide. Helicur 250 EW suppressed activities of all soil enzymes except for arylsulfatase. In addition, it proved to be a strong inhibitor of spring barley growth and development.


Asunto(s)
Fungicidas Industriales/toxicidad , Hordeum/crecimiento & desarrollo , Microbiota/efectos de los fármacos , Microbiología del Suelo/normas , Contaminantes del Suelo/toxicidad , Triazoles/toxicidad , Bacterias/efectos de los fármacos , Bacterias/enzimología , Hongos/efectos de los fármacos , Hongos/enzimología , Fungicidas Industriales/análisis , Metagenoma/efectos de los fármacos , Microbiota/genética , Hojas de la Planta/crecimiento & desarrollo , Suelo/química , Contaminantes del Suelo/análisis , Triazoles/análisis
20.
Environ Pollut ; 256: 113463, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31677875

RESUMEN

Growing evidence suggests that metallic oxide nanoparticles can pose a severe risk to the health of invertebrates. Previous attention has been mostly paid to the effects of metallic oxide nanoparticles on the survival, growth and physiology of animals. In comparison, the effects on gut microbiota and incidence of antibiotic resistance genes (ARGs) in soil fauna remain poorly understood. We conducted a microcosm study to explore the responses of the non-target soil invertebrate Enchytraeus crypticus gut microbiota and resistomes to copper oxide nanoparticles (CuO NPs) and copper nitrate by using bacterial 16S rRNA gene amplicons sequencing and high throughput quantitative PCR. The results showed that exposure to Cu2+ resulted in higher bioaccumulation (P < 0.05) and lower body weight and reproduction (P < 0.05) of Enchytraeus crypticus than exposure to CuO NPs. Nevertheless, exposure to CuO NPs for 21 days markedly increased the alpha-diversity of the gut microbiota of Enchytraeus crypticus (P < 0.05) and shifted the gut microbial communities, with a significant decline in the relative abundance of the phylum Planctomycetes (from 37.26% to 19.80%, P < 0.05) and a significant elevation in the relative abundance of the phyla Bacteroidetes, Firmicutes and Acidobacteria (P < 0.05). The number of detected ARGs in the Enchytraeus crypticus gut significantly decreased from 45 in the Control treatment to 16 in the Cu(NO3)2 treatment and 20 in the CuO NPs treatment. The abundance of ARGs in the Enchytraeus crypticus gut were also significantly decreased to 38.48% when exposure to Cu(NO3)2 and 44.90% when exposure to CuO NPs (P < 0.05) compared with the controls. These results extend our understanding of the effects of metallic oxide nanoparticles on the gut microbiota and resistome of soil invertebrates.


Asunto(s)
Cobre/toxicidad , Microbioma Gastrointestinal/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Oligoquetos/fisiología , Contaminantes del Suelo/toxicidad , Animales , Bacterias/efectos de los fármacos , Farmacorresistencia Microbiana/genética , Microbioma Gastrointestinal/fisiología , Microbiota/efectos de los fármacos , Nitratos , Oligoquetos/efectos de los fármacos , Oligoquetos/microbiología , ARN Ribosómico 16S , Suelo , Contaminantes del Suelo/análisis
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