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1.
J Vet Med Sci ; 86(5): 468-473, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38569837

RESUMEN

Streptococcus uberis is one of major pathogens causing bovine mastitis. However, there is poor information on antimicrobial resistance (AMR) among the Japanese isolates. To provide treatment information for the mastitis caused by S. uberis in Japan, we aimed to clarify AMR patterns of the isolates from bovine milk mainly in Chiba. AMR phenotyping/genotyping [blaZ-erm(A)-erm(B)-mef(A)-linB-lnuD-tet(M)-tet(O)-tet(K)-tet(L)-tet(S)] and multilocus sequence typing were performed to analyze relationships between AMR patterns and clonal complexes (CCs). Resistance to tetracycline-, macrolide-, and lincosamide-classes was mainly associated with possession of tet(O), tet(S), erm(B), linB, and lnuD genes. CC996 was significantly associated with multidrug resistance (P<0.0001). These findings will aid Chiba farm animal clinics in treating bovine mastitis.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Mastitis Bovina , Leche , Infecciones Estreptocócicas , Streptococcus , Animales , Bovinos , Streptococcus/efectos de los fármacos , Streptococcus/genética , Streptococcus/aislamiento & purificación , Japón , Leche/microbiología , Mastitis Bovina/microbiología , Femenino , Antibacterianos/farmacología , Infecciones Estreptocócicas/veterinaria , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/tratamiento farmacológico , Tipificación de Secuencias Multilocus , Genotipo , Pruebas de Sensibilidad Microbiana
2.
Bioorg Med Chem Lett ; 105: 129737, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38599297

RESUMEN

A new monoterpenoid, neoroseoside (1), along with two previously reported compounds, 2″-O-α-l-rhamnosyl-6-C-fucosylluteolin (2) and farobin A (3) were isolated from the Zea mays. The structure of compound 1 was determined through the analysis spectroscopic data, including mass spectrometry (MS), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) data. The absolute configurations of 1 were deduced from the comparing the values of optical rotations and from the interpretation of electronic circular dichroism (ECD) spectra. Compounds 2 and 3 displayed moderate antibacterial activity against Streptococcus mutans ATCC 25175 (inhibition rates 24 % and 28 %, respectively) and Streptococcus sobrinus ATCC 33478 (inhibition rate of 26 %), at a concentration of 100 µg/mL, whereas compound 1 did not have any significant antibacterial activities. The compounds 1-3 also showed anti-inflammatory activity on cytokine IL-6 and TNF-α.


Asunto(s)
Antibacterianos , Pruebas de Sensibilidad Microbiana , Monoterpenos , Zea mays , Zea mays/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Monoterpenos/farmacología , Monoterpenos/química , Monoterpenos/aislamiento & purificación , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Relación Estructura-Actividad , Estructura Molecular , Streptococcus mutans/efectos de los fármacos , Interleucina-6/metabolismo , Interleucina-6/antagonistas & inhibidores , Descubrimiento de Drogas , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo , Relación Dosis-Respuesta a Droga , Streptococcus/efectos de los fármacos
3.
Lett Appl Microbiol ; 74(6): 901-908, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35218013

RESUMEN

In the microbiome, probiotics modulate oral diseases. In this study, Streptococcus strain C17T was isolated from the oropharynx of a 5-year-old healthy child, and its potential probiotic properties were analysed using human bronchial epithelial cells (16-HBE) used as an in vitro oropharyngeal mucosal model. The results demonstrated that the C17T strain showed tolerance to moderate pH ranges of 4-5 and 0·5-1% bile. However, it was more tolerant to 0·5% bile than 1% bile. It also demonstrated an ability to accommodate maladaptive oropharyngeal conditions (i.e. tolerating lysozyme at 200 µg ml-1 ). It was also resistant to hydrogen peroxide at 0·8 mM. In addition, we found out that the strain possesses inhibitory activities against various common pathogenic bacteria. Furthermore, C17T was not cytotoxic to 16-HBE cells at different multiplicities of infection. Scanning electron microscopy disclosed that C17T adhesion to 16-HBE cells. Competition, exclusion and displacement assays showed that it had good anti-adhesive effect against S. aureus. The present study revealed that Streptococcus strain C17T is a potentially efficacious oropharyngeal probiotic.


Asunto(s)
Salud Bucal , Probióticos , Streptococcus , Adhesión Bacteriana , Preescolar , Humanos , Probióticos/farmacología , Staphylococcus aureus/efectos de los fármacos , Streptococcus/efectos de los fármacos , Streptococcus/genética
4.
Food Funct ; 13(4): 1774-1784, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35112684

RESUMEN

Antibiotic-resistant strains of Streptococcus uberis (S. uberis) frequently cause clinical mastitis in dairy cows resulting in enormous economic losses. The regulation of immunometabolism is a promising strategy for controlling this bacterial infection. To investigate whether taurine alleviates S. uberis infection by the regulation of host glycolysis via HIF1α, the murine mammary epithelial cell line (EpH4-Ev) and C57BL/6J mice were challenged with S. uberis. Our data indicate that HIF1α-driven glycolysis promotes inflammation and damage in response to the S. uberis challenge. The activation of HIF1α is dependent on mTOR-mediated ROS production. These results were confirmed in vivo. Taurine, an intracellular metabolite present in most animal tissues, has been shown to effectively modulate HIF1α-triggered metabolic reprogramming and contributes to a reduction of inflammation, which reduces mammary tissue damage and prevents mammary gland dysfunction in S. uberis-induced mastitis. These data provide a novel putative prophylactic and therapeutic strategy for amelioration of dairy cow mastitis and bacterial inflammation.


Asunto(s)
Glucólisis/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Infecciones Estreptocócicas/metabolismo , Taurina/farmacología , Animales , Línea Celular , Femenino , Glándulas Mamarias Animales/citología , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos , Streptococcus/efectos de los fármacos
5.
Fitoterapia ; 157: 105129, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35051555

RESUMEN

Tabernaecorymine A, an 18-normonoterpenoid indole alkaloid with conjugated (E)-3-aminoacrylaldehyde fragment was obtained from the stem bark of Tabernaemontana corymbosa. Its structure was elucidated by extensive spectroscopic data analyses, and further verified by ACD/structure elucidator, electronic circular dichroism (ECD) analyses and density functional theory (DFT) chemical shift predictions. The compound exhibited significant antibacterial bioactivity against Streptococcus dysgalactiae with an MIC value of 3.12 µg/mL, which is better than the plant drug berberine.


Asunto(s)
Antibacterianos/farmacología , Extractos Vegetales/farmacología , Alcaloides de Triptamina Secologanina/farmacología , Tabernaemontana/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Bacillus subtilis/efectos de los fármacos , Dicroismo Circular , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Alcaloides de Triptamina Secologanina/química , Alcaloides de Triptamina Secologanina/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Streptococcus/efectos de los fármacos
6.
J Microbiol ; 60(2): 167-176, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34997538

RESUMEN

"Antibiotic tolerance" promotes the rapid subsequent evolution of "antibiotic resistance," however, it is often overlooked because it is difficult to distinguish between tolerant and susceptible organisms. A commensal bacterium S. anginosus subsp. anginosus strain KHUD_S1, isolated from dental biofilm was found to exhibit a high MBC/MIC ratio of 32 against vancomycin. We observed KHUD_S1 cells exposed to vancomycin did not grow but maintained viability. Transmission electron microscope showed KHUD_S1 cells possessed a dense, thick capsule and maintained the cell wall integrity upon vancomycin exposure. To infer the underlying mechanisms of the vancomycin tolerance in KHUD_S1, we performed whole genome sequencing and RNA sequencing. The KHUD_S1 genome carried three genes encoding branching enzymes that can affect peptidoglycan structure through interpeptide bridge formation. Global gene expression profiling revealed that the vancomycin-induced downregulation of carbohydrate and inorganic ion transport/metabolism as well as translation is less prominent in KHUD_S1 than in the vancomycin susceptible strain KHUD_S3. Based on the transcriptional levels of genes related to peptidoglycan synthesis, KHUD_S1 was determined to have a 3D peptidoglycan architecture distinct from KHUD_S3. It was found that, under vancomycin exposure, the peptidoglycan was remodeled through changes in the interpeptide bridge and transpeptidation reactions. Collectively, these features of S. anginosus KHUD_S1, including a dense capsule and differential gene expression in peptidoglycan synthesis, may contribute to vancomycin tolerance. Our results showing the occurrence of vancomycin tolerance amongst oral commensal bacteria highlight the need for considering future strategies for screening of antibiotic tolerance as an effort to reduce antibiotic resistance.


Asunto(s)
Farmacorresistencia Bacteriana , Tolerancia a Medicamentos , Streptococcus/citología , Streptococcus/efectos de los fármacos , Streptococcus/genética , Vancomicina/farmacología , Antibacterianos/farmacología , Biopelículas , Humanos , Boca/microbiología , Análisis de Secuencia de ARN , Transcriptoma , Secuenciación Completa del Genoma
7.
Chembiochem ; 23(3): e202100423, 2022 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-34580974

RESUMEN

Streptococcus agalactiae or Group B Streptococcus (GBS) is a Gram-positive bacterial pathobiont that is the etiological cause of severe perinatal infections. GBS can colonize the vagina of pregnant patients and invade tissues causing ascending infections of the gravid reproductive tract that lead to adverse outcomes including preterm birth, neonatal sepsis, and maternal or fetal demise. Additionally, transmission of GBS during labor or breastfeeding can also cause invasive infections of neonates and infants. However, human milk has also been shown to have protective effects against infection; a characteristic that is likely derived from antimicrobial and immunomodulatory properties of molecules that comprise human milk. Recent evidence suggests that human milk oligosaccharides (HMOs), short-chain sugars that comprise 8-20 % of breast milk, have antimicrobial and anti-biofilm activity against GBS and other bacterial pathogens. Additionally, HMOs have been shown to potentiate the activity of antibiotics against GBS. This review presents the most recent published work that studies the interaction between HMOs and GBS.


Asunto(s)
Antibacterianos/farmacología , Leche Humana/química , Oligosacáridos/farmacología , Streptococcus/efectos de los fármacos , Antibacterianos/química , Conformación de Carbohidratos , Humanos , Pruebas de Sensibilidad Microbiana , Oligosacáridos/química
8.
Microbiol Spectr ; 9(3): e0175121, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34787437

RESUMEN

A low initial contamination level of the meat surface is the sine qua non to extend the subsequent shelf life of ground beef for as long as possible. Therefore, the short- and long-term effects of a pregrinding treatment with electrolyzed water (EW) on the microbiological and physicochemical features of Piedmontese steak tartare were here assessed on site, by following two production runs through storage under vacuum packaging conditions at 4°C. The immersion of muscle meat in EW solution at 100 ppm of free active chlorine for 90 s produced an initial surface decontamination with no side effects or compositional modifications, except for an external color change that was subsequently masked by the grinding step. However, the initially measured decontamination was no longer detectable in ground beef, perhaps due to a quick recovery by bacteria during the grinding step from the transient oxidative stress induced by the EW. We observed different RNA-based metataxonomic profiles and metabolomic biomarkers (volatile organic compounds [VOCs], free amino acids [FAA], and biogenic amines [BA]) between production runs. Interestingly, the potentially active microbiota of the meat from each production run, investigated through operational taxonomic unit (OTU)-, oligotyping-, and amplicon sequence variant (ASV)-based bioinformatic pipelines, differed as soon as the early stages of storage, whereas microbial counts and biomarker dynamics were significantly distinguishable only after the expiration date. Higher diversity, richness, and abundance of Streptococcus organisms were identified as the main indicators of the faster spoilage observed in one of the two production runs, while Lactococcus piscium development was the main marker of shelf life end in both production runs. IMPORTANCE Treatment with EW prior to grinding did not result in an effective intervention to prolong the shelf life of Piedmontese steak tartare. Our RNA-based approach clearly highlighted a microbiota that changed markedly between production runs but little during the first shelf life stages. Under these conditions, an early metataxonomic profiling might provide the best prediction of the microbiological fate of each batch of the product.


Asunto(s)
Contaminación de Alimentos/análisis , Lactococcus/crecimiento & desarrollo , Microbiota/efectos de los fármacos , Carne Roja/microbiología , Streptococcus/crecimiento & desarrollo , Agua/farmacología , Animales , Bovinos , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Almacenamiento de Alimentos/métodos , Lactococcus/efectos de los fármacos , Lactococcus/aislamiento & purificación , Streptococcus/efectos de los fármacos , Streptococcus/aislamiento & purificación , Agua/química , Microbiología del Agua
9.
J Nanosci Nanotechnol ; 21(6): 3539-3546, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34739805

RESUMEN

We have developed a simple, robust environment-friendly and efficient method for ZnO nanoparticles biosynthesis using Dalbergia sissoo fresh leaf extract. Before using these nanoparticles for antimicrobial assay, a detailed characterization was performed using techniques like Ultraviolet/Visible (UV/Vis) spectroscopy, Particle size analysis (PSA), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM),Transmission electron microscopy (TEM) etc. The average size of biosynthesized ZnO nanoparticles was around 30 nm and they were pure and crystalline by nature. The effectiveness of these biosynthesized nanoparticles were checked against both pathogenic and non-pathogenic microbes. A total of eight bacterial strains-Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Klebsilla pneumoniae, Staphylococcus aureus, Streptococcus entericus, Bacillus cereus, Pantoea cypripedii and three fungal strains-Candida albicans, Aspergilus niger and Aspergilus flavus were studied to have a clear view of the spectrum of ZnO nanoparticles anti-microbial activity. The effectiveness of biosynthesized ZnO nanoparticles against the microbes was found to be better than the standard reference antibiotics used (streptomycin, chloramphenicol and rifampicin). The results seem to be very promising and can be used for some practical applications of ZnO nanoparticles in nearfuture.


Asunto(s)
Antibacterianos , Antifúngicos , Nanopartículas del Metal , Óxido de Zinc , Antibacterianos/farmacología , Antifúngicos/farmacología , Aspergillus/efectos de los fármacos , Bacillus/efectos de los fármacos , Candida/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pantoea/efectos de los fármacos , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Streptococcus/efectos de los fármacos , Difracción de Rayos X , Óxido de Zinc/farmacología
10.
BMC Complement Med Ther ; 21(1): 265, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34670535

RESUMEN

BACKGROUND: Oils in traditional medicine are important products and used routinely for therapeutic purposes. Rose oil (Rosa damascene Mill), a product of Persian medicine, is advised for the treatment of Infectious diseases related to the female genitourinary tract. In the present study, R. damascena petal oil, aqueous, and hydroalcoholic extracts were evaluated for their in vitro antibacterial and anti-Trichomonas vaginalis effects. METHODS: Anti-trichomonas activity evaluation of extracts and oil were assayed by the Homocytometery method. Their antibacterial effects against Escherichia coli, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and clinically isolated Group B Streptococcus were assayed by broth microdilution in 96-well plates. RESULTS: The MIC of hydroalcoholic and aqueous extracts ranged from 25-50 and 25-100 mg/ml, respectively. Rose oil at all administered doses failed to show any antibacterial activity. CONCLUSION: All extracts and oil concentrations showed some degree of growth inhibition activity on T. vaginalis; however, hydroalcoholic extract was more efficient.


Asunto(s)
Antibacterianos/farmacología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Trichomonas vaginalis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Irán , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Rosa , Streptococcus/efectos de los fármacos
11.
Pak J Pharm Sci ; 34(3(Supplementary)): 1149-1156, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34602445

RESUMEN

As part of our continuous research to understand the interaction mechanism of drug and metallo-elements, heavy metal complexes of azithromycin (AZI) were synthesized with arsenic oxide, lead carbonate and silver chloride salts in molar ratio of 2: 1 (L: M). Synthesized heavy metal complexes have shown good percent yield and characterized through spectroscopic parameters including UV-Visible, TLC, FT-IR, NMR and elemental analysis (CHN). Spectroscopic characterization reveals the binding of ligand AZI with heavy metals in bi-dentate manner involving the hydroxide and 9a-NCH3 group of the aglycone ring of AZI. These newly synthesized heavy metal complexes were evaluated for their antimicrobial response against selected gram positive and gram negative organisms and antifungal species. It was noted that all newly synthesized complexes exhibits increased activity against B.subtilus whereas, AZI itself didn't show any activity, while synthesized complexes have low to moderate response against all the studied organisms. Complex A-M12 possess greater enzymatic response against both urease and alpha chymotrypsin among all the studied complexes. Results obtained were then statistically analyzed through one way ANOVA and Dunnett's test by using SPSS version 20.0 suggesting the significant response of complexes against selected organisms.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Trióxido de Arsénico/farmacología , Azitromicina/farmacología , Carbonatos/farmacología , Complejos de Coordinación/farmacología , Plomo/farmacología , Compuestos de Plata/farmacología , Trióxido de Arsénico/química , Azitromicina/análogos & derivados , Azitromicina/química , Bacillus subtilis/efectos de los fármacos , Candida albicans/efectos de los fármacos , Carbonatos/química , Quimotripsina/metabolismo , Citrobacter/efectos de los fármacos , Complejos de Coordinación/química , Pruebas Antimicrobianas de Difusión por Disco , Pruebas de Enzimas , Escherichia coli/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Plomo/química , Micrococcus luteus/efectos de los fármacos , Proteus mirabilis/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Salmonella typhi/efectos de los fármacos , Shigella flexneri/efectos de los fármacos , Compuestos de Plata/química , Staphylococcus aureus/efectos de los fármacos , Streptococcus/efectos de los fármacos , Ureasa/metabolismo
12.
Sci Rep ; 11(1): 18461, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34531515

RESUMEN

Antibiotic resistance is a serious threat that occurs globally in the health sector due to increased consumption of inappropriate antibiotics. Guidelines for prescribing antibiotics for ARTIs have been issued in general practice to promote rational antibiotic prescribing. This study was conducted to compare the effectiveness of cefixime and tetracycline as a solution to improve monitoring of appropriate antibiotic use in the treatment of ARTIs. All stock isolates were rejuvenated first, and cultured on standard media and Kirby-Bauer disc diffusion method was used for susceptibility testing in accordance with the Clinical and Laboratory Standard Institute's (CLSI) recommendations. Identification of bacteria from a single isolate was carried out to determine which bacteria were resistant to cefixime and tetracycline. A total of 466 single isolates of bacteria were analyzed, which showed a percentage of resistance to cefixime 38.0%, and tetracycline 92.86%. Bacterial isolates were resistant to cefixime and tetracycilne was a genus of Haemophilus, Streptococcus, Corynebacterium, Staphylococcus, and bordetella. Cefixime compared to tetracycline was proven to be superior in terms of the effectiveness of ARIs treatment.


Asunto(s)
Antibacterianos/toxicidad , Cefixima/toxicidad , Farmacorresistencia Bacteriana , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Tetraciclina/toxicidad , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Bordetella/efectos de los fármacos , Cefixima/administración & dosificación , Cefixima/uso terapéutico , Corynebacterium/efectos de los fármacos , Pruebas Antimicrobianas de Difusión por Disco , Cálculo de Dosificación de Drogas , Haemophilus/efectos de los fármacos , Humanos , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/microbiología , Staphylococcus/efectos de los fármacos , Streptococcus/efectos de los fármacos , Tetraciclina/administración & dosificación , Tetraciclina/uso terapéutico
13.
Prev Vet Med ; 194: 105451, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34364060

RESUMEN

Livestock has been recognized as a reservoir of antibiotic-resistant bacteria. Prevalence of resistance has been associated with herd size and intensification of animal production systems. Brazil is one of the emergent hotspots of bacterial resistance, which is also associated with animal husbandry. This study aimed to evaluate the resistance profile of pathogens that cause subclinical mastitis and the relationship between resistance status at farm level and different production systems. Milk samples from cows diagnosed with subclinical mastitis were collected from farms that adopt different husbandry systems with different production intensities, i.e., agroecological, low input, high input, Free-Stall and Compost-bedded pack barn. Etiological agents were isolated and microbiologically identified, and antibiotic susceptibility testing was conducted, using the disk diffusion method. The main isolated agents were Streptococcus spp. (n = 54, 30.5 %) and coagulase-positive Staphylococcus (CPS) (n = 54; 30.5 %). The recovered isolates displayed high antibiotic resistance against Sulfamethazine (80.2 %), Gentamicin (29.37 %), Penicillin (29.37 %), Oxacillin (28.82 %) and Ampicillin (26 %). Multidrug resistance was found for all agents and in all farming systems (39.54 %). Neither production systems (p = 0.26) nor farming systems (p = 0.24) significantly affected the resistance rates of samples. Therefore, intensive production systems may not be a root cause of increased rates of antimicrobial resistance in the milk production chain, suggesting that other environmental factors should be investigated. It is noteworthy that high levels of multidrug resistance were even found in bacteria earlier considered as minor pathogens. This development can be taken as a warning that environmental bacteria are potential transmitters of resistance genes to the environment.


Asunto(s)
Enfermedades de los Bovinos , Farmacorresistencia Bacteriana , Mastitis Bovina , Infecciones Estafilocócicas , Animales , Antibacterianos/farmacología , Bovinos , Enfermedades de los Bovinos/microbiología , Industria Lechera , Femenino , Mastitis Bovina/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Leche , Infecciones Estafilocócicas/veterinaria , Staphylococcus/efectos de los fármacos , Staphylococcus/aislamiento & purificación , Streptococcus/efectos de los fármacos , Streptococcus/aislamiento & purificación
14.
Int J Biol Macromol ; 188: 473-481, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34352320

RESUMEN

ß-defensin family plays a critical role in host defense against infections. In this study, we found that pBD129 are widely expressed in porcine tissues such as the intestine, liver, and spleen. Interestingly, the expression level of pBD129 in most tissues was higher in Tibetan pigs than in DLY (Duroc × Landrace × Yorkshire) pigs (P < 0.05), and was significantly upregulated upon E. coli K88 infection (P < 0.05). The pBD129 protein was successfully expressed in E. coli and the molecule weight was estimated by SDS-PAGE to be 37.2 kDa. Mass spectrometry verified the protein as a pBD129. The protein showed antibacterial activities against Streptococcus and E. coli DH5α with a minimal inhibitory concentration (MIC) of 32 µg/mL. Hemolytic and cytotoxicity assays indicated that pBD129 had no detrimental effect on cell viability. Importantly, pBD129 significantly reduced the apoptosis of porcine intestinal epithelial cells exposure to bacterial endotoxins, which was associated with down-regulation of inflammatory cytokines such as the IL-1ß, IL-6 and TNFα (P < 0.05), and down-regulation of apoptosis-related genes such as the caspase-3, caspase-8, and caspase-9 (P < 0.05). These results suggested that pBD129 is a novel modulator of innate immunity involved in mammalian inflammatory responses.


Asunto(s)
Infecciones por Escherichia coli/terapia , Factores Inmunológicos/genética , Inflamación/genética , beta-Defensinas/genética , Animales , Apoptosis/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/veterinaria , Regulación de la Expresión Génica/efectos de los fármacos , Factores Inmunológicos/farmacología , Inflamación/inducido químicamente , Inflamación/patología , Inflamación/terapia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Lipopolisacáridos/toxicidad , Pruebas de Sensibilidad Microbiana , Streptococcus/efectos de los fármacos , Streptococcus/patogenicidad , Porcinos , beta-Defensinas/farmacología
15.
Vet Ital ; 57(1): 41-47, 2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34313097

RESUMEN

Streptococcal species are known to be responsible for bovine mastitis. The aim of the present study was to determine antimicrobial drug resistance patterns of hemolytic streptococci distributed according to Lancefield serogrouping. Streptococcus sp. strains were isolated from 124 bovine milk samples from 31 cows with subclinical or clinical mastitis submitted to Mehmet Akif Ersoy University Faculty of Veterinary Medicine, Department of Microbiology Laboratory in Burdur province, Turkey from January 2015 to January 2017. A total of 63 Streptococcus sp. were isolated and the most frequently obtained isolates were classified as Lancefield's serogroup B (84.13%), the remaining isolates as serogroup F (15.87%). Out of 63 isolates, 53 (84.13%) showed beta­hemolytic activity whereas 10 (15.87%) alpha­hemolytic activity. Antimicrobial resistance was assessed by disk diffusion test against the most common antibiotics used in the field. Among the 63 Streptococcus sp. tested, the highest antimicrobial resistance patterns were observed for neomycin (95.24%), trimethoprim sulphamethoxazole (87.30%) and gentamicin (69.84%). None of the isolates showed resistance to amoxicillin­clavulanic acid, except for one serogroup F isolate. The resistance rates for the other antimicrobials ranged from 1.59% to 38.04%. A total of 50 isolates exibited multi­drug resistance to ≥ 3 antimicrobial agents tested. Overall, our results suggested that there is an urgent need to enhance awareness among the dairy farmers in choosing the appropriate drug for treating mastitis.


Asunto(s)
Antibacterianos/uso terapéutico , Programas de Optimización del Uso de los Antimicrobianos , Farmacorresistencia Bacteriana , Mastitis Bovina/tratamiento farmacológico , Streptococcus/aislamiento & purificación , Animales , Antibacterianos/farmacología , Bovinos , Industria Lechera , Femenino , Mastitis Bovina/microbiología , Streptococcus/efectos de los fármacos , Turquía/epidemiología
16.
Appl Environ Microbiol ; 87(16): e0039121, 2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34105992

RESUMEN

Antimicrobial peptides are evolving as novel therapeutic options against the increasing problem of multidrug-resistant microorganisms, and nisin is one such avenue. However, some bacteria possess a specific nisin resistance system (NSR), which cleaves the peptide reducing its bactericidal efficacy. NSR-based resistance was identified in strains of Streptococcus uberis, a ubiquitous pathogen that causes mastitis in dairy cattle. Previous studies have demonstrated that a nisin A derivative termed nisin PV, featuring S29P and I30V, exhibits enhanced resistance to proteolytic cleavage by NSR. Our objective was to investigate the ability of this nisin derivative to eradicate and inhibit biofilms of S. uberis DPC 5344 and S. uberis ATCC 700407 (nsr+) using crystal violet (biomass), 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) (viability) assays, and confocal microscopy (viability and architecture). When preestablished biofilms were assessed, both peptides reduced biofilm biomass by over 60% compared to that of the untreated controls. However, a 42% higher reduction in viability was observed following treatment with nisin PV compared to that of nisin A. Accordingly, confocal microscopy analysis revealed significantly more dead cells on the biofilm upper surface and a reduced thickness following treatment with nisin PV. When biofilm inhibition was assessed, nisin PV inhibited biofilm formation and decreased viability up to 56% and 85% more than nisin A, respectively. Confocal microscopy analysis revealed a lack of biofilm for S. uberis ATCC 700407 and only dead cells for S. uberis DPC 5344. These results suggest that nisin PV is a promising alternative to effectively reduce the biofilm formation of S. uberis strains carrying NSR. IMPORTANCE One of the four most prevalent species of bovine mastitis-causing pathogens is S. uberis. Its ability to form biofilms confers on the bacteria greater resistance to antibiotics, requiring higher doses to be more effective. In a bid to limit antibiotic resistance development, the need for alternative antimicrobials is paramount. Bacteriocins such as nisin represent one such alternative that could alleviate the impact of mastitis caused by S. uberis. However, many strains of S. uberis have been shown to possess nisin resistance determinants, such as the nisin resistance protein (NSR). In this study, we demonstrate the ability of nisin and a nisin derivative termed PV that is insensitive to NSR to prevent and remove biofilms of NSR-producing S. uberis strains. These findings will add new information to the antimicrobial bacteriocins and control of S. uberis research fields specifically in relation to biofilms and nsr+ mastitis-associated strains.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Nisina/química , Nisina/farmacología , Streptococcus/efectos de los fármacos , Bioingeniería , Farmacorresistencia Bacteriana , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Nisina/genética , Streptococcus/crecimiento & desarrollo , Streptococcus/fisiología
17.
Bioorg Chem ; 114: 105078, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34161878

RESUMEN

This study was focused on the synthesis of new pyrimidines 4a,b, 5a,b and pyrazoles 6a, b as ATP mimicking tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR). The new compounds were assessed as cytotoxic candidates against human breast cancer cells (MCF-7) and hepatocellular carcinoma cells (HepG-2). All the new compounds appeared as more potent cytotoxic agents than erlotinib, while only compound 4a exhibited more potency than 5-flourouracil and 4b analogue was equipotent to it. Accordingly, the kinase suppression effect of 4a and 4b was further evaluated against EGFRWT, EGFRL858R and EGFRT790M. Both pyrimidine analogues 4a and 4b displayed outstanding inhibitory activity against EGFRWT and its two mutated isoforms EGFRL858R and EGFRT790M in comparing to erlotinib and osimertinib as reference drugs. Additionally, all the new analogues were subjected to antimicrobial assay. Interestingly, both 4a and 4b represented the most promising activity of wide spectrum antimicrobial effect against the examined microbes in comparison to gentamycin and ketoconazole as standard drugs. Moreover, docking results proved the good binding interactions of the compounds 4a and 4b with EGFRWT and EGFRT790M which were in accordance with the results of the in vitro enzyme assay. Additional in silico ADMET studies were performed for the new derivatives which represented their good oral absorption, good drug-likeness properties and low toxicity risks in human.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Antineoplásicos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Pirimidinas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antifúngicos/síntesis química , Antifúngicos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Aspergillus fumigatus/efectos de los fármacos , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Mucorales/efectos de los fármacos , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteus vulgaris/efectos de los fármacos , Pirazoles/síntesis química , Pirazoles/química , Pirimidinas/síntesis química , Pirimidinas/química , Streptococcus/efectos de los fármacos , Relación Estructura-Actividad
18.
J Infect Dev Ctries ; 15(5): 672-677, 2021 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-34106891

RESUMEN

INTRODUCTION: Streptococcus pneumoniae can be responsible for severe human infections. Optochin resistance has been a potential cause of misidentification of pneumococcus and other members of the mitis group. Hence, rapid and easy optochin resistant (Optr) S. pneumoniae identification is essential. METHODOLOGY: Atypical pneumococci were characterized using optochin susceptibility, bile solubility based on spectrophotometric reading, serotyping, pulsed field gel electrophoresis (PFGE), 16S rRNA sequencing and PCR-based assays targeting pneumococcal genes lytA, ply, pspA, cpsA, Spn9802 and Spn9828. RESULTS: Optical density values for the bile solubility test suggest the identification of four Optr S. pneumoniae and one Streptococcus pseudopneumoniae. All Optr pneumococci harbored cpsA, lytA, ply, Spn9802, Spn9828 and pspA genes. Only ply, spn9802 and Spn9828 genes were detected in S. pseudopneumoniae. The 16S rRNA sequencing differentiates between these two species. Optr S. pneumoniae strains belonged to different genotypes and serotypes (14, 19A, 3 and 9V). Three Optr S. pneumoniae isolates were typed as pspA family 2, while one belonged to pspA family 1. Sequencing of the atpA and atpC gene of the Optr variants revealed three mutations in the ATPase a-subunit (L99I, M23V and V52I) and one mutation in ATPase c-subunit (V48I). CONCLUSIONS: Our data indicate that bile OD-values provides an accurate, fast and easy method to discriminate between Optr S. pneumoniae and other Streptococcus mitis group. Moreover molecular techniques, confirming the bile test, can be used in order to prevent these atypical pneumococci and alert clinical microbiologists of the presence of these strains in the community.


Asunto(s)
Quinina/análogos & derivados , Infecciones Estreptocócicas/diagnóstico , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus/aislamiento & purificación , Farmacorresistencia Bacteriana , Genes Bacterianos , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Técnicas de Diagnóstico Molecular , Quinina/farmacología , Quinina/uso terapéutico , ARN Ribosómico 16S , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/microbiología , Streptococcus/efectos de los fármacos , Streptococcus/genética , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/genética , Túnez/epidemiología
19.
Korean J Parasitol ; 59(2): 173-178, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33951774

RESUMEN

The DM9 domain is a protein unit of 60-75 amino acids that has been first detected in the fruit fly Drosophila as a repeated motif of unknown function. Recent research on proteins carrying DM9 domains in the mosquito Anopheles gambiae and the oyster Crassostrea gigas indicated an association with the uptake of microbial organisms. Likewise, in the trematode Fasciola gigantica DM9-1 showed intracellular relocalization following microbial, heat and drug stress. In the present research, we show that FgDM9-1 is a lectin with a novel mannose-binding site that has been recently described for the protein CGL1 of Crassostrea gigas. This property allowed FgDM9-1 to agglutinate gram-positive and -negative bacteria with appropriate cell surface glycosylation patterns. Furthermore, FgDM9-1 caused hemagglutination across all ABO blood group phenotypes. It is speculated that the parenchymal located FgDM9-1 has a role in cellular processes that involve the transport of mannose-carrying molecules in the parenchymal cells of the parasite.


Asunto(s)
Proteínas del Helminto/farmacología , Lectina de Unión a Manosa/farmacología , Aglutinación , Secuencia de Aminoácidos , Animales , Bacterias/citología , Bacterias/efectos de los fármacos , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Fasciola/química , Fasciola/genética , Proteínas del Helminto/química , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Hemaglutinación/efectos de los fármacos , Humanos , Lectina de Unión a Manosa/química , Lectina de Unión a Manosa/genética , Lectina de Unión a Manosa/metabolismo , Alineación de Secuencia , Streptococcus/citología , Streptococcus/efectos de los fármacos
20.
Daru ; 29(1): 133-145, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33966255

RESUMEN

BACKGROUND: Punica granatum L. (pomegranate) with astringent activities and Matricaria chamomilla L. (chamomile) with anti-inflammatory and antioxidant properties are natural remedies used for various skin disorders, including wound healing. OBJECTIVES: This study was conducted to evaluate the individual and combined wound healing activity of the methanol extracts of pomegranate and chamomile flowers. METHODS: After preparing the menthol fraction of pomegranate and chamomile flowers, the content of total phenols, total tannins, and total flavonoids of fractions was measured. For standardization of pomegranate and chamomile fractions, Gallic acid and apigenin-7-O-glucoside contents of them were determined using high-performance liquid chromatography (HPLC). Moreover, their antioxidant activities were examined using DPPH and FRAP tests. The antimicrobial assay was performed against Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Three different concentrations of methanol fraction of each plant and one combination dose of fractions were investigated for their wound healing activities in an excision wound model on the rats' dorsum. Finally, histopathological studies were done at the end of the experiment. RESULTS: Phytochemical examinations showed high amounts of phenolic compounds in pomegranate flowers, while chamomile flower fractions contained a high amount of total flavonoids. Both fractions, especially pomegranate, had potent antioxidant activity. The best results for wound closure were observed 7 days after wound induction. All treated groups exhibited superior wound contraction compared to their placebo at all measurement times. The combined form of pomegranate and chamomile had better wound healing properties compared to a single therapy, especially on time earlier to wound induction. CONCLUSION: This study represented high antioxidant and wound healing activities for methanol fraction of pomegranate and chamomile flowers, which could be related to their high content of phytochemicals. In comparison with single herb treatment, the combined form of these two fractions in lower concentrations accelerated wound closure.


Asunto(s)
Antibacterianos/uso terapéutico , Antiinflamatorios/uso terapéutico , Antioxidantes/uso terapéutico , Matricaria , Extractos Vegetales/uso terapéutico , Granada (Fruta) , Cicatrización de Heridas/efectos de los fármacos , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Compuestos de Bifenilo/química , Flavonoides/análisis , Flores , Masculino , Fenoles/análisis , Fitoquímicos/análisis , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Picratos/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Ratas Wistar , Piel/efectos de los fármacos , Piel/patología , Staphylococcus aureus/efectos de los fármacos , Streptococcus/efectos de los fármacos , Taninos/análisis
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