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1.
Antibiotics (Basel) ; 13(4)2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38667040

RESUMEN

Respiratory tract infections (RTIs) are the leading cause of antibiotic prescriptions, primarily due to the risk for secondary bacterial infections. In this study, we examined whether Echinacea could reduce the need for antibiotics by preventing RTIs and their complications, and subsequently investigated its safety profile. A comprehensive search of EMBASE, PubMed, Google Scholar, Cochrane DARE and clinicaltrials.gov identified 30 clinical trials (39 comparisons) studying Echinacea for the prevention or treatment of RTIs in 5652 subjects. Echinacea significantly reduced the monthly RTI occurrence, risk ratio (RR) 0.68 (95% CI 0.61-0.77) and number of patients with ≥1 RTI, RR = 0.75 [95% CI 0.69-0.81] corresponding to an odds ratio 0.53 [95% CI 0.42-0.67]. Echinacea reduced the risk of recurrent infections (RR = 0.60; 95% CI 0.46-0.80), RTI complications (RR = 0.44; 95% CI 0.36-0.54) and the need for antibiotic therapy (RR = 0.60; 95% CI 0.39-0.93), with total antibiotic therapy days reduced by 70% (IRR = 0.29; 95% CI 0.11-0.74). Alcoholic extracts from freshly harvested Echinacea purpurea were the strongest, with an 80% reduction of antibiotic treatment days, IRR 0.21 [95% CI 0.15-0.28]. An equal number of adverse events occurred with Echinacea and control treatment. Echinacea can safely prevent RTIs and associated complications, thereby decreasing the demand for antibiotics. Relevant differences exist between Echinacea preparations.

2.
PLOS Glob Public Health ; 3(12): e0001615, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38055697

RESUMEN

In response to the coronavirus pandemic (COVID-19) and scale up of diagnostic testing, the Canadian Microbiology Proficiency Testing program created a new proficiency testing (PT) program for the molecular and antigen detection of SARS-CoV-2. The program was geared to point of care testing (POCT) sites located in each of the eight provincial Health Authorities across British Columbia, Canada, with the intention to monitor testing quality. The PT program consisted of 6 shipments in a year, each containing a set of 4 samples either positive for SARS-CoV-2 virus or negative. The program began with initial 23 sites enrolling in March 2021, expanding to >100 participants by December 2021. After the first two surveys, it was observed that testing performance (accuracy) was consistently acceptable for sites using nucleic acid technology (NAT), however performance by sites using rapid antigen detection (RAD) methods was poor, especially when testing the weakly positive samples. A root cause investigation of poor testing performance revealed gaps in the execution of testing methods and also in results interpretation. These quality issues were most commonly associated with new testers who lacked experience with diagnostic testing. Tester training and mentoring was reinforced as was retraining of personnel; sample processing instructions were modified, and a training video was also created for testing sites. As a result of these interventions, sites improved their testing accuracy and the performance of POCT sites using RAD methods came to more closely match the performance of sites utilizing NAT. Overall, the PT program was highly successfully and improved quality of testing in the province. This work demonstrates the critical value of an external quality assessment (EQA) partner towards improving patient and public health and safety, especially when testing is conducted outside of an accredited medical laboratory setting.

3.
Mol Biomed ; 3(1): 43, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36508083

RESUMEN

GSK3ß has been proposed to have an essential role in Coronaviridae infections. Screening of a targeted library of GSK3ß inhibitors against both SARS-CoV-2 and HCoV-229E to identify broad-spectrum anti-Coronaviridae inhibitors resulted in the identification of a high proportion of active compounds with low toxicity to host cells. A selected lead compound, T-1686568, showed low micromolar, dose-dependent activity against SARS-CoV-2 and HCoV-229E. T-1686568 showed efficacy in viral-infected cultured cells and primary 2D organoids. T-1686568 also inhibited SARS-CoV-2 variants of concern Delta and Omicron. Importantly, while inhibition by T-1686568 resulted in the overall reduction of viral load and protein translation, GSK3ß inhibition resulted in cellular accumulation of the nucleocapsid protein relative to the spike protein. Following identification of potential phosphorylation sites of Coronaviridae nucleocapsid, protein kinase substrate profiling assays combined with Western blotting analysis of nine host kinases showed that the SARS-CoV-2 nucleocapsid could be phosphorylated by GSK3ß and PKCa. GSK3ß phosphorylated SARS-CoV-2 nucleocapsid on the S180/S184, S190/S194 and T198 phospho-sites, following previous priming in the adjacent S188, T198 and S206, respectively. Such inhibition presents a compelling target for broad-spectrum anti-Coronaviridae compound development, and underlies the mechanism of action of GSK3ß host-directed therapy against this class of obligate intracellular pathogens.

4.
Microorganisms ; 10(11)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36363737

RESUMEN

SARS-CoV-2 variants of concern (VOCs) represent an alarming threat as they show altered biological behavior and may escape vaccination effectiveness. Broad-spectrum antivirals could play an important role to control infections. The activity of Echinacea purpurea (Echinaforce® extract, EF) against (i) VOCs B1.1.7 (alpha), B.1.351.1 (beta), P.1 (gamma), B1.617.2 (delta), AV.1 (Scottish), B1.525 (eta), and B.1.1.529.BA1 (omicron); (ii) SARS-CoV-2 spike (S) protein-pseudotyped viral particles and reference strain OC43 as well as (iii) wild type SARS-CoV-2 (Hu-1) was analyzed. Molecular dynamics (MD) were applied to study the interaction of Echinacea's phytochemical markers with known pharmacological viral and host cell targets. EF extract broadly inhibited the propagation of all investigated SARS-CoV-2 VOCs as well as the entry of SARS-CoV-2 pseudoparticles at EC50's ranging from 3.62 to 12.03 µg/mL. The preventive addition of 25 µg/mL EF to epithelial cells significantly reduced sequential infection with SARS-CoV-2 (Hu-1) and OC43. MD analyses showed constant binding affinities to VOC-typical S protein variants for alkylamides, caftaric acid, and feruloyl-tartaric acid in EF extract and interactions with serine protease TMPRSS-2. EF extract demonstrated stable virucidal activity across seven tested VOCs, likely due to the constant affinity of the contained phytochemical substances to all spike variants. A possible interaction of EF with TMPRSS-2 partially would explain the cell protective benefits of the extract by the inhibition of membrane fusion and cell entry. EF may therefore offer a supportive addition to vaccination endeavors in the control of existing and future SARS-CoV-2 virus mutations.

5.
Future Sci OA ; 8(7): FSO808, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36248067

RESUMEN

The use of facial protection has been adopted globally due to the COVID-19 pandemic. We dissected four respirators and one surgical mask into layers to determine whether or not the virus adheres to them. These individual layers were contaminated with the SARS-CoV-2 Delta variant, and its release by vortexing was performed. Samples were used to infect Vero cells, and a plaque assay was used to evaluate the adherence of the virus to the layers. Results showed that a cumulative log reduction of the layers reduced the load of the virus by at least sixfold. Our study confirms the effectiveness of facial protection in reducing the transmission and/or infection of SARS-CoV-2.

6.
Virus Res ; 233: 51-59, 2017 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-28279802

RESUMEN

Viral infections may predispose the airways to secondary bacterial infections that can lead to unfavorable progression of principally self-limiting illnesses. Such complicated respiratory infections include pneumonia, bronchitis, sinusitis, acute otitis media, and sepsis, which cause high morbidity and lethality. Some of the pathogenic consequences of viral infections, like the expression of bacterial adhesion receptors and the disturbance of physical barrier integrity due to inflammation, may create permissive conditions for co-infections. Influenza virus A (H3N2) is a major pathogen that causes secondary bacterial infections and inflammation that lead to pneumonia. The herbal medicine Echinacea purpurea, on the other hand, has been widely used to prevent and treat viral respiratory infections, and recent clinical data suggest that it may prevent secondary infection complications as well. We investigated the role of standardized E. purpurea (Echinaforce® extract or EF) on H3N2-induced adhesion of live nontypeable Haemophilus influenzae (NTHi) and Staphylococcus aureus, along with the expression of bacterial receptors, intracellular adhesion molecule-1 (ICAM-1), fibronectin, and platelet activating factor receptor (PAFr), by BEAS-2B cells. Inflammatory processes were investigated by determining the cellular expression of IL-6 and IL-8 and the involvement of Toll-like receptor (TLR-4) and NFκB p65. We found that influenza virus A infection increased the adhesion of H. influenzae and S. aureus to bronchial epithelial cells via upregulated expression of the ICAM-1 receptor and, to some extent, of fibronectin and PAFr. Echinaforce (EF) significantly reduced the expression of ICAM-1, fibronectin, and PAFr and consequently the adhesion of both bacterial strains. EF also effectively prevented the super-expression of inflammatory cytokines by suppressing the expression of NFκB and possibly TLR-4. These results indicate that E. purpurea has the potential to reduce the risk of respiratory complications by preventing virus-induced bacterial adhesion and through the inhibition of inflammation super-stimulation (cytokine storms).


Asunto(s)
Antiinfecciosos/farmacología , Echinacea/química , Células Epiteliales/efectos de los fármacos , Sobreinfección/prevención & control , Receptor Toll-Like 4/antagonistas & inhibidores , Factor de Transcripción ReIA/antagonistas & inhibidores , Línea Celular , Coinfección , Células Epiteliales/citología , Células Epiteliales/microbiología , Células Epiteliales/virología , Fibronectinas/genética , Fibronectinas/inmunología , Regulación de la Expresión Génica , Haemophilus influenzae/efectos de los fármacos , Haemophilus influenzae/crecimiento & desarrollo , Haemophilus influenzae/patogenicidad , Interacciones Huésped-Patógeno , Humanos , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Subtipo H3N2 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H3N2 del Virus de la Influenza A/patogenicidad , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Interleucina-8/genética , Interleucina-8/inmunología , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/microbiología , Pulmón/virología , Extractos Vegetales/farmacología , Glicoproteínas de Membrana Plaquetaria/genética , Glicoproteínas de Membrana Plaquetaria/inmunología , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/inmunología , Transducción de Señal , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/patogenicidad , Sobreinfección/microbiología , Sobreinfección/virología , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/inmunología
7.
Res Vet Sci ; 109: 21-28, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27892870

RESUMEN

Bovine respiratory disease complex (BRDc) is a multi-factorial disease, involving both viral and bacterial pathogens, that negatively impacts the cattle feedlot industry. A nitric oxide releasing solution (NORS) has been developed and shown to have potential in the prevention of BRDc. This study investigated the underlying immunological mechanisms through which the nitroslyating agent NORS provides protection against the development of BRDc in susceptible cattle. An in vitro BRDc experimental model was designed using bovine peripheral blood mononuclear cells (PBMCs) which were infected with bovine herpesvirus 1 (BHV-1) and subsequently cultured with lipopolysaccharides (LPS) extracted from Mannheimia haemolytica bacteria. The cells were treated with NORS following viral infection to reflect the timing of administering the NORS treatment in feedlots during initial processing. An expression and protein analysis of key genes involved in the innate immune response was carried out. The BRDc model produced significant increases in gene expression (p<0.01) and protein release (p<0.05) of the proinflammatory cytokines IL-1ß and TNF. Treatment with NORS reduced the protein levels of IL-1ß (0.39-fold↓) (p<0.05) and TNF (0.48-fold↓) (p<0.01) in the BRDc experimental group when compared against the non-treatment BRDc controls. TLR4 expression, having been significantly reduced under the BRDc experimental conditions (0.33-fold↓) (p<0.05), increased significantly (0.76-fold↑) (p<0.05) following NORS treatment. This study provides evidence suggesting that NO may protect against the development of BRDc by limiting deleterious inflammation while simultaneously increasing TLR4 expression and enhancing the ability of the host to detect and respond to bacterial pathogens.


Asunto(s)
Complejo Respiratorio Bovino/inmunología , Herpesvirus Bovino 1/inmunología , Leucocitos Mononucleares/fisiología , Lipopolisacáridos/toxicidad , Mannheimia haemolytica/metabolismo , Óxido Nítrico/metabolismo , Animales , Bovinos , Células Cultivadas , Citocinas/genética , Regulación de la Expresión Génica/inmunología , Lipopolisacáridos/inmunología , Mannheimia haemolytica/inmunología
8.
Nitric Oxide ; 31: 48-53, 2013 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-23562771

RESUMEN

Gaseous nitric oxide (gNO) is an approved vasodilator drug for inhalation up to a maximum dose of 80 ppm. While gNO has been shown, in vitro, to be an effective antibacterial agent (at 160 ppm), NO-donor compounds have been shown to inhibit a variety of viruses at varying stages of replication. This research was done in order to determine whether gNO at 80 or 160 ppm possesses an antiviral effect on influenza viruses. Three strains of influenza (A and B) were exposed to gNO for up to 180 min, before and after infection of MDCK cells. In search for possible mechanism of antiviral action, Neuraminidase (NA) inhibition assay of H1N1 that was exposed to gNO was performed. Results show that when virions were exposed to gNO prior to infection a complete inhibition of infectivity was achieved for all three strains. Post infection exposure of influenza with gNO resulted in about 30% inhibition of infectivity. Further testing showed that when eliminating the pH effect by exposing a dried virus to gNO, 90% inhibition was found after 2h exposure. NA activity, of whole dried H1N1 virus, was found to be inhibited by gNO (80%). These results suggest that 80 and 160 ppm gNO have a time dependent antiviral effect on influenza strains of viruses during various stages of cellular infection, which are not due to concomitant changes in pH in the surrounding milieu. Viral NA inhibition by gNO was shown and may be responsible for this antiviral effect.


Asunto(s)
Alphainfluenzavirus/fisiología , Antivirales/farmacología , Betainfluenzavirus/fisiología , Gripe Humana/prevención & control , Óxido Nítrico/farmacología , Infecciones por Orthomyxoviridae/prevención & control , Replicación Viral/efectos de los fármacos , Análisis de Varianza , Animales , Perros , Gases/farmacología , Humanos , Concentración de Iones de Hidrógeno , Gripe Humana/virología , Alphainfluenzavirus/patogenicidad , Betainfluenzavirus/patogenicidad , Células de Riñón Canino Madin Darby , Neuraminidasa/antagonistas & inhibidores , Infecciones por Orthomyxoviridae/virología , Reproducibilidad de los Resultados
9.
Int J Environ Res Public Health ; 8(12): 4477-87, 2011 12.
Artículo en Inglés | MEDLINE | ID: mdl-22408584

RESUMEN

Cedar leaf oil (CLO), derived from the Western red cedar, Thuja plicata, was evaluated as a safe and acceptable broad spectrum antimicrobial agent, with a view to its potential applications in buildings, including the alleviation of sick building syndrome. Various Gram-positive and Gram-negative human bacteria, and two fungal organisms, all known to be common environmental sources of potential infection, were selected and tested quantitatively, and all of them were found to be susceptible to CLO liquid and vapor. Bacterial spores and Aspergillus niger were sensitive, although less so than the vegetative bacteria. Similar tests with cultured human lung cells showed that continuous exposure to CLO vapor for at least 60 minutes was not toxic to the cells. Based on these results, CLO shows promise as a prospective safe, green, broad-spectrum anti-microbial agent for decontamination of buildings.


Asunto(s)
Antiinfecciosos/farmacología , Hojas de la Planta/química , Aceites de Plantas/farmacología , Thuja/química , Pruebas de Sensibilidad Microbiana
10.
Phytother Res ; 19(9): 740-3, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16220564

RESUMEN

The methanol extract of the underground part of Rhodiola rosea was found to show inhibitory activity against Staphylococcus aureus. Bioactivity-guided fractionation of a 95% ethanol extract from the stems of R. rosea led to the isolation of five compounds: gossypetin-7-O-L-rhamnopyranoside (1), rhodioflavonoside (2), gallic acid (3), trans-p-hydroxycinnamic acid (4) and p-tyrosol (5). Their structures were elucidated by UV, IR, MS and NMR data, as well as by comparison with those of the literature. Compounds 1 and 2 were evaluated for their antibacterial and antiprostate cancer cell activities. Compounds 1 and 2 exhibited activity against Staphylococcus aureus with minimum inhibitory concentrations of 50 microg/mL and 100 microg/mL, respectively. Cytotoxicity studies of 1 and 2 also displayed activity against the prostate cancer cell line with IC(50) values of 50 microg/mL and 80 microg/mL, respectively.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos Fitogénicos/farmacología , Fitoterapia , Extractos Vegetales/farmacología , Rhodiola , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antineoplásicos Fitogénicos/administración & dosificación , Antineoplásicos Fitogénicos/uso terapéutico , Línea Celular Tumoral , Humanos , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Raíces de Plantas , Tallos de la Planta
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