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1.
Braz. j. biol ; 83: e248083, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1278546

RESUMEN

Abstract Species of the genus Cordia have shown biological activities, such as anti-inflammatory, analgesic, antioxidant, antiviral, and antifungal activities. The species Cordia glabrata (MART) A.DC. Has no information concerning its phytochemical profile and possible biological activities. Thus, this study aimed to evaluate this profile in ethanolic extracts of young, adult and senescent leaves, as well as their antioxidant, photoprotective, antimicrobial, and virucidal potentials. Phytochemical analysis was performed by TLC (thin-layer chromatography) and showed the presence of flavonoids, tannins, and terpenes. The evaluation by UPLC-MS/MS (Ultra performance liquid chromatography - tandem mass spectrometer) evidenced the presence of caffeic (3.89 mgL-1), p-cumaric (6.13 mgL-1), and ferulic (0.58 mgL-1) acids, whilst, in GC/MS (Gas chromatography-mass spectrometry) analysis there was a greater amount of palmitic (51.17%), stearic (20.34%), linoleic (9.62%), and miristic (8.16%) fatty acids. The DPPH (2,2-Diphenyl-1-picrylhydrazyl) and ABTS+ (2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radicals were used to verify the potential antioxidant activity, observing a better activity for the leaf extract in the adult phenological stage: 54.63 ± 1.06 µgmL-1 (DPPH) and 44.21 ± 1.69 mM (ABTS). The potential photoprotective activity of the extracts was determined by spectrophotometry and the in vitro values of SPF (Sun Protection Factor) in young and adult leaves (5.47 and 5.41, respectively) showed values close to the minimum SPF of 6.0 required by ANVISA (Brazilian Health Regulatory Agency). It was not observed an antimicrobial activity for Staphylococcus aureus with a minimum inhibitory concentration of 2000 μgmL-1, however the anti-herpetic assay against the Herpes simplex virus type 2 (HSV-2) showed a potent virucidal activity at the tested concentrations with CV50 value <0.195 μgmL-1 and a Selectivity Index (SI = CC50 / CV50) greater than 448. The results obtained in this study suggest that extracts of leaves of C. glabrata in their adult phenological stage have potential antioxidant, photoprotective and virucidal activity, considering in vitro test results.


Resumo Espécies do gênero Cordia apresentam atividades biológicas, como anti-inflamatória, analgésica, antioxidante, antiviral e antifúngica. Para a espécie Cordia glabrata (MART) A.DC., ainda não existem informações sobre seu perfil fitoquímico e possíveis atividades biológicas, deste modo, o presente estudo teve como objetivo avaliar este perfil em extratos etanólicos de folhas jovens, adultas e senescentes, bem como o potencial antioxidante, fotoprotetor, antimicrobiano e virucida. A análise fitoquímica foi realizada por CCD (Cromatografia em Camada Delgada), mostrando a presença de flavonóides, taninos e terpenos. Na avaliação por CLAE EM/EM (Cromatografia Líquida de Ultra Eficiência acoplada a Espectrometria de Massas) foi evidenciado a presença dos ácidos caféico (3,89 mgL-1), p-cumárico (6,13 mgL-1) e ferúlico (0,58 mgL-1), paralelamente, na CG/EM (Cromatografia Gasosa acoplada a Espectrometria de Massas) verificou-se maior quantidade dos ácidos graxos palmítico (51,17%), esteárico (20,34%), linoléico (9,62%) e mirístico (8,16%). Os radicais DPPH (2,2-Difenil-1-picrilhidrazil) e ABTS+ (2′-Azino-bis (ácido 3-etilbenzotiazolina-6-sulfônico)) foram utilizados para verificar o potencial antioxidante, observando-se uma atividade superior para o extrato da folha em sua fase fenológica adulta: 54,63 ± 1,06 µgmL-1 (DPPH) e 44,21 ± 1,69 mM (ABTS+). A potencial atividade fotoprotetora dos extratos foi determinada espectrofotometricamente e os valores in vitro de FPS (Fator de Proteção Solar) em folhas jovens e adultas (5,47 e 5,41 respectivamente) apresentaram valores próximos ao FPS mínimo de 6,0 exigido pela ANVISA (Agência Nacional de Vigilância Sanitária). Não foi observada atividade antimicrobiana para Staphylococcus aureus sendo a concentração inibitória mínima de 2000 μgmL-1, no entanto o ensaio anti-herpético contra o vírus Herpes simplex tipo 2 (HSV-2) mostrou uma potente atividade virucida nas concentrações testadas com um valor de CV50 <0,195 μgmL-1 e um Índice de Seletividade (IS = CC50 / CV50) maior que 448. Os resultados obtidos neste estudo sugerem que extratos de folhas de C. glabrata em seu estágio fenológico adulto apresentam potencial antioxidante, fotoprotetora e virucida, considerando os resultados de testes in vitro.


Asunto(s)
Cordia , Antiinfecciosos , Antivirales/farmacología , Brasil , Extractos Vegetales/farmacología , Cromatografía Liquida , Hojas de la Planta , Espectrometría de Masas en Tándem , Antioxidantes/farmacología
2.
Braz. j. biol ; 83: e245753, 2023. tab
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1278536

RESUMEN

Abstract The species Eugenia involucrata DC. is a plant native to Brazil and is traditionally used for intestinal problems, however, little research has documented about its biological potential and phytochemical profile. Thus, the objective of this study was to carry out preliminary phytochemical prospecting, antimicrobial and antioxidant potential of E. involucrata extracts. Using the E. involucrata leaves, aqueous and organic extracts were obtained using the following solvents (ethanol, methanol, hexane, acetone, dichloromethane and ethyl acetate). The phytochemical prospecting detected the presence of saponins, steroids, flavonoids and tannins in the extracts. Ethanolic and methanolic extracts presented antimicrobial activity for most of the bacterial strains tested, as well as for yeast Candida albicans, with concentrations between 3.12 and 50 mg/mL. The ethanolic and metanolic extract presented high free radical sequestration potential (>90%). The methanol extract showed an IC50 value statistically equal to that found for the commercial antioxidant BHT (p <0.05). The crude extracts obtained with ethanol and methanol were the most promising. These results suggest that methanolic, ethanolic and aqueous extracts are a promising source of natural bioactive.


Resumo A espécie Eugenia involucrata DC. é uma planta nativa do Brasil e tradicionalmente utilizada para problemas intestinais, porém, poucas pesquisas documentam sobre seu potencial biológico e perfil fitoquímico. Assim, o objetivo deste trabalho foi realizar uma prospecção fitoquímica preliminar, o potencial antimicrobiano e antioxidante dos extratos de E. involucrata. A partir das folhas de E. involucrata, foram obtidos extratos aquosos e orgânicos com os seguintes solventes (etanol, metanol, hexano, acetona, diclorometano e acetato de etila). A prospecção fitoquímica detectou a presença de saponinas, esteroides, flavonóides e taninos nos extratos. Os extratos etanólico e metanólico apresentaram atividade antimicrobiana para a maioria das cepas bacterianas testadas, assim como para a levedura Candida albicans, com concentrações entre 3,12 e 50 mg/mL. Os extratos etanólico e metanólico apresentaram alto potencial de sequestro de radicais livres (> 90%). O extrato metanólico apresentou IC50 estatisticamente igual ao encontrado para o antioxidante comercial BHT (p <0,05). Os extratos brutos obtidos com etanol e metanol foram os mais promissores. Esses resultados sugerem que os extratos metanólico, etanólico e aquoso são uma fonte promissora de bioativos naturais.


Asunto(s)
Eugenia , Antiinfecciosos/farmacología , Brasil , Extractos Vegetales/farmacología , Hojas de la Planta , Fitoquímicos , Antioxidantes/farmacología
3.
Braz. j. biol ; 83: e244675, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1339348

RESUMEN

Abstract Several species of thymus have therapeutic properties, so they are used in traditional medicine. In this work was carried out to synthesize Thymus vulgalis silver nanoparticles (TSNPS) and evaluate antioxidant and antimicrobial activities of TSNPS and T. vulgalis essential oil extract (TEOE). The essential oils analyzed by GC-MS and were characterized. Major compounds of phenol, 2 methyl 5 (1 methylethyle) (CAS), thymol and 1,2 Benzene dicarboxylic acid, 3 nitro (CAS) (48.75%, 32.42% and 8.12%, respectively) were detected. Results demonstrated that the TSNPS gave a highest DPPH radical scavenging activity, it was obtained 97.2 at 1000 ug/ml. TSNPS, Thymus + Hexane (T+H), Thymus + Ethanol (T+E) gave the greatest antimicrobial activity than amoxicillin (AM) and ciprofloxacin (CIP). In conclusion: The essential oil of thymus (Vulgaris) and thymus (Vulgaris) silver nanoparticles can be a good source of natural preservatives as an antioxidant and antimicrobial agents for increasing the shelf life of foodstuffs.


Resumo Diversas espécies de timo possuem propriedades terapêuticas, por isso são utilizadas na medicina tradicional. Neste trabalho foi realizado para sintetizar nanopartículas de prata Thymus vulgalis (TSNPS) e avaliar as atividades antioxidante e antimicrobiana de TSNPS e extrato de óleo essencial de T. vulgalis (TEOE). Os óleos essenciais analisados por GC-MS e foram caracterizados. Os principais compostos de fenol, 2 metil 5 (1 metiletilo) (CAS), timol e ácido 1,2 Benzenodicarboxílico, 3 nitro (CAS) (48,75%, 32,42% e 8,12%, respectivamente) foram detectados. Os resultados demonstraram que o TSNPS deu uma maior atividade de eliminação do radical DPPH , foi obtido 97,2 a 1000 ug / ml. TSNPS, Timo + Hexano (T + H), Timo + Etanol (T + E) deu a maior atividade antimicrobiana do que amoxicilina (AM) e ciprofloxacina (CIP). Em conclusão: O óleo essencial de nanopartículas de prata do timo (Vulgaris) e do timo (Vulgaris) pode ser uma boa fonte de conservantes naturais como agentes antioxidantes e antimicrobianos para aumentar a vida útil de alimentos.


Asunto(s)
Aceites Volátiles/farmacología , Thymus (Planta) , Nanopartículas del Metal , Antiinfecciosos/farmacología , Plata , Antioxidantes/farmacología
4.
Braz. j. biol ; 83: e244551, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1285626

RESUMEN

Abstract Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin alongwith marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.


Resumo Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.


Asunto(s)
Animales , Conejos , Aceites Volátiles , Origanum , Antiinfecciosos/toxicidad , Extractos Vegetales/toxicidad , Hígado , Antioxidantes
5.
Braz. j. biol ; 83: e244435, 2023. tab, graf
Artículo en Inglés | MEDLINE, LILACS, VETINDEX | ID: biblio-1285619

RESUMEN

Abstract Increasing trend in antimicrobial resistance and failure of chemically synthesized antibiotics lead to discover alternative methods for the treatment of bacterial infections. Various medicinal plants are in use traditionally and their active compounds can be further applied for treatment of bacterial diseases. This study was designed to determine the antibacterial activity of Punica granatum (P. granatum L.) (pomegranate) peel extract against Enterobacteriaceae [Escherichia coli (E. coli), Salmonella Typhimurium (S. Typhimurium) and Shigella Dysenteriae (S. Dysenteriae)] and gram-positive bacterium [Staphylococcus aureus (Staph aureus)]. Methanolic extract of P. granatum L. peel was prepared by Soxhlet apparatus method. Total flavonoid and phenolic contents from the extract were determined by High Performance Liquid Chromatography (HPLC). The antibacterial activity of P. granatum L. peel extract was evaluated through agar well diffusion method. HPLC showed the range of phenolics (gallic acid, caffeic acid, benzoic acid, cinnamic acid) and flavonoid compounds. The chemical structures of flavonoid and phenolics found in the methanolic extract of P. granatum L. peel have been reported for the first time. The methanolic peel extract (50 ul) of yellow P. granatum L. showed 26, 10, 10 and 9mm zones of inhibition (ZOI) against S. aureus, S. Typhimurium, S. Dysenteriae and E. coli, respectively. The methanolic extract of red P. granatum L. (100 ul) showed 27, 8, 12 and 15 mm ZOI against Staph. aureus, S. Typhimurium, S. Dysenteriae and E. coli, respectively. Highest ZOI was observed against Staph. aureus. Many of the bacteria studied in the present work may cause serious gastrointestinal infections, which can lead to hemorrhagic diarrhea in children. These infections can be life-threatening to young children and the elderly. There is an incentive to find alternative control measures, such as plant and herbal extracts, especially in lesser-developed countries where traditional antibiotics may not be readily available.


Resumo A tendência crescente na resistência antimicrobiana e na falha dos antibióticos sintetizados quimicamente leva à descoberta de métodos alternativos para o tratamento de infecções bacterianas. Várias plantas medicinais estão em uso tradicionalmente e seus compostos ativos podem ser posteriormente aplicados para o tratamento de doenças bacterianas. Este estudo foi desenhado para determinar a atividade antibacteriana do extrato de casca de Punica granatum (P. granatum L.) (romã) contra Enterobacteriaceae [Escherichia coli (E. coli), Salmonella Typhimurium (S. Typhimurium) e Shigella Dysenteriae (S. Dysenteriae) ] e bactéria gram-positiva [Staphylococcus aureus (Staph aureus)]. O extrato metanólico da casca de P. granatum L. foi preparado pelo método do aparelho de Soxhlet. O conteúdo total de flavonoides e fenólicos do extrato foi determinado por cromatografia líquida de alta eficiência (HPLC). A atividade antibacteriana do extrato da casca de P. granatum L. foi avaliada através do método de difusão em ágar. HPLC mostrou a gama de compostos fenólicos (ácido gálico, ácido cafeico, ácido benzoico, ácido cinâmico) e flavonoides. As estruturas químicas de flavonoides e fenólicos encontradas no extrato metanólico da casca de P. granatum L. foram relatadas pela primeira vez. O extrato metanólico da casca (50 ul) de P. granatum L. amarelo apresentou zonas de inibição (ZOI) de 26, 10, 10 e 9mm contra S. aureus, S. Typhimurium, S. Dysenteriae e E. coli, respectivamente. O extrato metanólico de P. granatum L. vermelho (100 ul) apresentou 27, 8, 12 e 15 mm IOI contra Staph. aureus, S. Typhimurium, S. Dysenteriae e E. coli, respectivamente. O ZOI mais alto foi observado contra Staph. aureus. Muitas das bactérias estudadas no presente trabalho podem causar infecções gastrointestinais graves, que podem levar à diarreia hemorrágica em crianças. Essas infecções podem ser fatais para crianças pequenas e idosos. Há um incentivo para encontrar medidas de controle alternativas, como extratos de plantas e ervas, especialmente em países menos desenvolvidos, onde os antibióticos tradicionais podem não estar prontamente disponíveis.


Asunto(s)
Humanos , Preescolar , Niño , Anciano , Granada (Fruta) , Staphylococcus aureus , Extractos Vegetales/farmacología , Cromatografía Líquida de Alta Presión , Escherichia coli , Antiinfecciosos
6.
J Oleo Sci ; 71(5): 701-708, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35491095

RESUMEN

The use of bacteria in the synthesis of silver nanoparticles (AgNPs) emerges as an ecofriendly and exciting approach. In the present study, we reported the biosynthesis of AgNPs by using culture supernatant of the bacteria Bacillus licheniformis (MN900686). The biogenically synthesized AgNPs were confirmed by the change in the color of the culture filtrate from yellow to brown after the addition of AgNO3. Further characterization performed by means of UV vis-spectroscopy showed absorption peak at 414 nm which confirmed the formation of AgNPs. Fourier Transfer infrared (FTIR) confirmed the involvement of biological molecules in the formation of nanoparticles (NPs). The SEM revealed that the NPs have approximately 38 nm size. The agar well diffusion assay was used to determine antibacterial activity while tube dilution method was used to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The human pathogenic bacterial strains i.e., P. aeruginosa (MN900691) and B. subtilis (MN900684), were used as test strains. The anti-bacterial assay against test strains revealed that these NPs showed concentration dependent increased zone of inhibition (ZOI). The maximum ZOI at 25 µL of AgNPs was 20 mm against B. subtilis after 24 hours of incubation. One-way ANOVA test showed significant ZOI (p ≤ 0.05) against B. subtilis. The MIC was ranged from 4.3-6.6 µg/mL while MBC ranged from 8.3 to 6.6 µg/mL. Overall, this study suggested that the biogenically synthesized NPs are an effective alternative source of antimicrobials against pathogenic bacteria.


Asunto(s)
Antiinfecciosos , Bacillus licheniformis , Nanopartículas del Metal , Antibacterianos/química , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Bacterias , Humanos , Nanopartículas del Metal/química , Plata/química , Plata/farmacología
7.
Yakugaku Zasshi ; 142(5): 527-534, 2022.
Artículo en Japonés | MEDLINE | ID: mdl-35491159

RESUMEN

Antimicrobial stewardship (AS) intervention strategy is a critical process in promoting appropriate antibiotic use, thus preventing unnecessarily prolonged therapy and reducing antimicrobial resistance (AMR). Although limiting unnecessary carbapenem use by AS intervention is speculated to reduce AMR, there is a lack of specific data on the efficacy of AS team (AST) intervention regarding carbapenem-resistant Pseudomonas aeruginosa (CRPA). Consequently, this study aimed to evaluate the impact of our AS strategy on carbapenem use and CRPA. The AS intervention strategy was launched in July 2017 and consisted of daily audits and feedback on carbapenem use. We evaluated the 4-year prescription trend, including the rate of switching to other antimicrobials, and the rate of CRPA and the days of therapy required prior to and after the beginning of the AST intervention. The rate of switching to narrow-spectrum antibiotics and the discontinuation of carbapenem treatment were significantly higher in the pre-intervention period compared with the post-intervention period. (7.0% vs. 14.5%; p<0.001; 54.1% vs. 50.9%; p=0.027). However, there were no significant differences in the rate of CRPA prior to and after the beginning of the AST intervention. Furthermore, there was no correlation found between consumption and resistance rate (Pearson's r=0.123). Our results suggest that it is extremely important for AST to promote de-escalation and reduce unnecessary use, while the combination of process and outcome indicators other than antimicrobial consumption and resistance rate are required for the evaluation of the AS programs.


Asunto(s)
Antiinfecciosos , Programas de Optimización del Uso de los Antimicrobianos , Antibacterianos/uso terapéutico , Programas de Optimización del Uso de los Antimicrobianos/métodos , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Pseudomonas aeruginosa
8.
Front Cell Infect Microbiol ; 12: 804611, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35493730

RESUMEN

Objectives: To investigate the potential impact of the syndromic multiplex FilmArray® Pneumonia plus Panel (FAPP) on the antimicrobial treatment guidance of patients with ventilated hospital-acquired pneumonia (VHAP). Methods: Respiratory fluids from 100 adult patients with VHAP, receiving invasive mechanical ventilation in three intensive care units from one French university hospital, were tested prospectively using FAPP. Conventional cultures were performed in parallel as routine practice. Clinicians were left blinded to the FAPP results. Antimicrobial therapies based on FAPP results were simulated by independent blinded experts according to a predefined algorithm and compared to 1) those prescribed in practice according to local guidelines (real-life), and 2) those that complied with the international ERS/ESICM/ESCMID/ALAT recommendations. The primary endpoint was the number of days of broad-spectrum antimicrobial therapy. Secondary endpoints were the rates of microbiological treatment failure and cost-effectiveness ratio. Results: The predicted median duration of broad-spectrum antibiotics was 0 [0-1.25] day in the FAPP-based simulation, versus 2 [0-6] days in real-life (p<0.0001) and 2 [2-3.25] days in the recommendations-based simulation (p<0.0001). Treatment failure was predicted in 3% of cases with FAPP results versus observed in 11% in real-life (p=0.08) and 6% with recommendations-based simulation (p=0.37). The incremental cost-effectiveness ratio was 1 121 € [-7021; 6794] to avoid one day of non-optimized antimicrobial therapy. Conclusions: Our results suggest that using FAPP in patients with VHAP has the potential to reduce the use of broad-spectrum antimicrobial therapy without increasing the risk of microbial treatment failure.


Asunto(s)
Antiinfecciosos , Neumonía Asociada a la Atención Médica , Adulto , Antibacterianos/uso terapéutico , Antiinfecciosos/uso terapéutico , Enfermedad Crítica , Neumonía Asociada a la Atención Médica/tratamiento farmacológico , Hospitales , Humanos , Reacción en Cadena de la Polimerasa Multiplex
9.
Bone Joint J ; 104-B(5): 575-580, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35491584

RESUMEN

Periprosthetic joint infection (PJI) is a difficult complication requiring a comprehensive eradication protocol. Cure rates have essentially stalled in the last two decades, using methods of antimicrobial cement joint spacers and parenteral antimicrobial agents. Functional spacers with higher-dose antimicrobial-loaded cement and antimicrobial-loaded calcium sulphate beads have emphasized local antimicrobial delivery on the premise that high-dose local antimicrobial delivery will enhance eradication. However, with increasing antimicrobial pressures, microbiota have responded with adaptive mechanisms beyond traditional antimicrobial resistance genes. In this review we describe adaptive resistance mechanisms that are relevant to the treatment of PJI. Some mechanisms are well known, but others are new. The objective of this review is to inform clinicians of the known adaptive resistance mechanisms of microbes relevant to PJI. We also discuss the implications of these adaptive mechanisms in the future treatment of PJI. Cite this article: Bone Joint J 2022;104-B(5):575-580.


Asunto(s)
Antiinfecciosos , Artritis Infecciosa , Infecciones Relacionadas con Prótesis , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/uso terapéutico , Artritis Infecciosa/tratamiento farmacológico , Farmacorresistencia Bacteriana , Humanos , Infecciones Relacionadas con Prótesis/tratamiento farmacológico
10.
Andes Pediatr ; 93(1): 65-77, 2022 Feb.
Artículo en Español | MEDLINE | ID: mdl-35506778

RESUMEN

INTRODUCTION: Febrile neutropenia (FN) is the most frequent hemato-oncological emergency, with high morbidi ty and mortality in pediatrics. The objective of the study was the microbiological characterization and antimicrobial susceptibility of infections associated with FN in pediatric hemato-oncological patients. PATIENTS AND METHOD: Retrospective cohort study with patients aged between 1 month and 18 years, with onco-hematological pathology according to ICD-10 codes, hospitalized in a tertiary healthcare center in Bucaramanga, Colombia. Based on the medical records of the period 2013-2017, the episodes of FN were identified, and the isolated microorganisms and their susceptibility pattern were described. Biochemical identification and antimicrobial susceptibility testing were performed with the Dade Behring Microscan« automated system. The resistant microorganism classification was performed based on the Minimum Inhibitory Concentration (MIC) and the interpretation of the laboratory according to the cut-off points of the Clinical and Laboratory Standards Institute recommendations. RESULTS: Of 130 patients, 14.7% of the cultures obtained were positive. Bloods tream infection was observed in 17.5% of the episodes. The isolated microorganisms were mainly Gram-negative bacteria (75.8%). Enterobacteriaceae (EB) were the most frequent, led by Klebsiella pneumoniae, Escherichia coli, followed by Pseudomonas aeruginosa and coagulase-negative Staphylo cocci. Of the EBs, 40.5% showed resistance to Piperacillin/Tazobactam, 33.3% to Cefepime, and 8.2% to Meropenem. According to the antimicrobial resistance pattern, it was observed that 16.4% of the positive EB cultures had an extended-spectrum beta-lactamase pattern and 5% a pattern suggestive of carbapenemases. All Gram-positive cocci were sensitive to Vancomycin. CONCLUSION: In the studied patients, the predominant pathogenic microorganisms were Gram-negative ones with resistance in dices similar to those of developing countries.


Asunto(s)
Antiinfecciosos , Neutropenia Febril , Pediatría , Antiinfecciosos/farmacología , Niño , Enterobacteriaceae , Neutropenia Febril/complicaciones , Neutropenia Febril/tratamiento farmacológico , Humanos , Lactante , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos
11.
Methods Mol Biol ; 2469: 65-78, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35508830

RESUMEN

The biological production of nanoparticles has taken center stage among the various generation methods available owing to its environment-friendly characteristics and reduced energy requirements. A protocol for pigment-assisted silver nanoparticle (AgNP) synthesis was established, employing an extracellular composite pigment produced by the Ascomycota Talaromyces purpurogenus (presently Talaromyces purpureogenus). The extracellular pigment can reduce the precursor silver salt into nanoparticles in the presence of sodium hydroxide and light. Transmission electron microscopy may be used to characterize the bio-generated nanoparticles, which can also be tested for their biological properties using antimicrobial and anticancer assays.


Asunto(s)
Antiinfecciosos , Antineoplásicos , Nanopartículas del Metal , Antibacterianos , Antiinfecciosos/farmacología , Plata/farmacología , Talaromyces
12.
Methods Mol Biol ; 2451: 607-619, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35505037

RESUMEN

The current increase in antibiotic resistance worldwide and the emergence of microbial strains that are resistant to all known antibiotics have stimulated research into novel strategies such as aPDI that are thought to be unlikely to lead to the development of resistance. Although many studies have reported in vitro aPDI killing of microorganisms by a range of different photosensitizers, there are still limitations to the effectiveness of aPDI, and recurrence of bacterial growth may occur in animal studies after completion of the illumination. In this chapter we cover a novel and relatively simple method to improve the efficacy of aPDI against Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and fungal yeast Candida albicans by the addition of potassium iodide, a nontoxic inorganic salt. Under some circumstances up to six-logs additional killing can be obtained.


Asunto(s)
Antiinfecciosos , Yoduro de Potasio , Animales , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Escherichia coli , Fármacos Fotosensibilizantes/farmacología , Yoduro de Potasio/farmacología
13.
Methods Mol Biol ; 2451: 621-630, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35505038

RESUMEN

Antimicrobial photodynamic inactivation (aPDI) involves the use of a nontoxic dye or photosensitizer excited with visible light to produce reactive oxygen species that can kill all classes of microorganisms. Antimicrobial photodynamic therapy (aPDT) can be used in vivo as an alternative therapeutic strategy to treat localized infections due to its ability to selectively kill microbes while preserving host mammalian cells. aPDI can be potentiated by the addition of the nontoxic inorganic salt potassium iodide (KI). KI is an approved drug for antifungal therapy. The mechanism of potentiation with iodide is likely to be singlet oxygen addition to iodide to form iodine radicals, hydrogen peroxide, and molecular iodine. A previous chapter in this volume described potentiation of aPDI in vitro by addition of KI, while in this chapter we address the ability of KI to potentiate aPDT in vivo using an animal model of localized fungal infection. We employed oral candidiasis in immunosuppressed mice caused by a bioluminescent strain of Candida albicans and monitored by bioluminescence imaging.


Asunto(s)
Antiinfecciosos , Yodo , Micosis , Fotoquimioterapia , Animales , Antibacterianos , Modelos Animales de Enfermedad , Yoduros , Mamíferos , Ratones , Fotoquimioterapia/métodos , Yoduro de Potasio/farmacología , Yoduro de Potasio/uso terapéutico
14.
Methods Mol Biol ; 2451: 671-689, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35505040

RESUMEN

Pathogens such as Staphylococcus aureus are able to survive in many types of host cells including phagocytes such as neutrophils and macrophages, thereby resulting in intracellular infections. Treatment of intracellular infections by conventional antimicrobials (e.g., antibiotics) is often ineffective due to low intracellular efficacy of the drugs. Thus, novel techniques which can enhance the activity of antimicrobials within cells are highly demanded. Our recent studies have shown that photochemical internalization (PCI) is a promising approach for improving the efficacy of antibiotics such as gentamicin against intracellular staphylococcal infection. In this chapter, we describe the protocols aiming to study the potential of PCI-antibiotic treatment for intracellular infections in vitro and in vivo using a RAW 264.7 cell infection model and a zebrafish embryo infection model. Proof of concept of this approach is demonstrated. The protocols are expected to prompt further development of PCI-antimicrobial based novel therapies for clinically challenging infectious diseases associated with intracellular survival of pathogens.


Asunto(s)
Antiinfecciosos , Infecciones Estafilocócicas , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus , Pez Cebra
15.
Methods Mol Biol ; 2451: 631-669, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35505039

RESUMEN

The emergence of microbial resistance to antimicrobials among several common pathogenic microbial strains is an increasing problem worldwide. Thus, it is urgent to develop not only new antimicrobial therapeutics to fight microbial infections, but also new effective, rapid, and inexpensive methods to monitor the efficacy of these new therapeutics. Antimicrobial photodynamic therapy (aPDT) and antimicrobial blue light (aBL) therapy are receiving considerable attention for their antimicrobial potential and represent realistic alternatives to antibiotics. To monitor the photoinactivation process provided by aPDT and aBL, faster and more effective methods are required instead of laborious conventional plating and overnight incubation procedures. Bioluminescent microbial models are very interesting in this context. Light emission from bioluminescent microorganisms is a highly sensitive indication of their metabolic activity and can be used to monitor, in real time, the effects of antimicrobial agents and therapeutics. This chapter reviews the efforts of the scientific community concerning the development of in vitro, ex vivo, and in vivo bioluminescent bacterial models and their potential to evaluate the efficiency of aPDT and aBL in the inactivation of bacteria.


Asunto(s)
Antiinfecciosos , Fotoquimioterapia , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Bacterias , Pruebas Inmunológicas , Fotoquimioterapia/métodos
16.
Front Immunol ; 13: 789366, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35493523

RESUMEN

Local tissue acidosis affects anti-tumor immunity. In contrast, data on tissue pH levels in infected tissues and their impact on antimicrobial activity is sparse. In this study, we assessed the pH levels in cutaneous Leishmania lesions. Leishmania major-infected skin tissue displayed pH levels of 6.7 indicating that lesional pH is acidic. Next, we tested the effect of low extracellular pH on the ability of macrophages to produce leishmanicidal NO and to fight the protozoan parasite Leishmania major. Extracellular acidification led to a marked decrease in both NO production and leishmanicidal activity of lipopolysaccharide (LPS) and interferon γ (IFN-γ)-coactivated macrophages. This was not directly caused by a disruption of NOS2 expression, a shortage of reducing equivalents (NAPDH) or substrate (L-arginine), but by a direct, pH-mediated inhibition of NOS2 enzyme activity. Normalization of intracellular pH significantly increased NO production and antiparasitic activity of macrophages even in an acidic microenvironment. Overall, these findings indicate that low local tissue pH can curtail NO production and leishmanicidal activity of macrophages.


Asunto(s)
Antiinfecciosos , Leishmania major , Antiinfecciosos/metabolismo , Antiparasitarios/metabolismo , Macrófagos , Óxido Nítrico/metabolismo
17.
PLoS One ; 17(5): e0267945, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35511776

RESUMEN

US military service members experiencing combat-related wounds have higher risk of infection by multidrug-resistant bacteria. The gold standard culture-based antimicrobial susceptibility testing (AST) is not feasible in the battlefield environment. Thus, a rapid deployable system for bacteria identification and AST directly from wound sample is urgently needed. We report the potential of a Rapid, Label-free Pathogen Identification (RAPID) diagnostic system based on ATR-FTIR method to detect and distinguish multi-drug resistant strains for six different species in the ESKAPEE group. Our RAPID system combines sample processing on-broad to isolate and enrich bacteria cells from wound sample, ATR-FTIR measurement to detect antimicrobial-induced bacterial cell spectral changes, and machine learning model for automated, objective, and quantitative spectral analysis and unknown sample classification. Based on experimental results, our RAPID system is a promising technology for label-free, sensitive (104 cfu/mL from mixture), species-specific (> 95% accuracy), rapid (< 10 min for identification, ~ 4 hours for AST) bacteria detection directly from wound samples.


Asunto(s)
Antiinfecciosos , Personal Militar , Infección de Heridas , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana , Infección de Heridas/diagnóstico , Infección de Heridas/tratamiento farmacológico
18.
Bull World Health Organ ; 100(5): 298-299, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35521036

RESUMEN

Antimicrobial misuse has risen sharply during the pandemic, exacerbating already worrying trends. Lynn Eaton reports.


Asunto(s)
Antiinfecciosos , Pandemias , Antiinfecciosos/uso terapéutico , Ansiedad , Humanos
19.
Antimicrob Resist Infect Control ; 11(1): 65, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35505391

RESUMEN

BACKGROUND: Blood culture diagnostics are critical tools for sepsis management and antimicrobial resistance (AMR) surveillance. A baseline study was conducted to assess reported sepsis case finding, blood culture diagnostics, antimicrobial susceptibility testing (AST) and antimicrobial use at secondary health care facilities to inform the development of diagnostic stewardship improvement strategies in Nigeria. METHODS: A cross-sectional online survey was conducted among 25 public secondary health care facilities in Abuja, Federal Capital Territory (FCT) and Lagos State in Nigeria to evaluate the capacity for pathogen identification and AST. Data were then prospectively extracted on all patients with reported suspected sepsis from electronic medical records from selected departments at two facilities in the Federal Capital Territory from October 2020 to May 2021 to further assess practices concerning sepsis case-finding, clinical examination findings, samples requested, and laboratory test results. Data were descriptively analysed, and a multivariate logistic regression analysis was conducted to determine factors associated with blood culture requests. RESULTS: In the online survey, 32% (8/25) of facilities reported performing blood cultures. Only one had access to a clinical microbiologist, and 28% (7/25) and 4% (1/25) used standard bacterial organisms for quality control of media and quality control strains for AST, respectively. At the two facilities where data abstraction was performed, the incidence of suspected sepsis cases reported was 7.1% (2924/41066). A majority of these patients came from the paediatrics department and were outpatients, and the median age was two years. Most did not have vital signs and major foci of infection documented. Blood cultures were only requested for 2.7% (80/2924) of patients, of which twelve were positive for bacteria, mainly Staphylococcus aureus. No clinical breakpoints were used for AST. Inpatients (adjusted odds ratio [aOR]: 7.5, 95% CI: 4.6-12.3) and patients from the urban health care facility (aOR:16.9, 95% CI: 8.1-41.4) were significantly more likely to have a blood culture requested. CONCLUSION: Low blood culture utilisation remains a key challenge in Nigeria. This has implications for patient care, AMR surveillance and antibiotic use. Diagnostic stewardship strategies should focus on improving access to clinical microbiology expertise, practical guidance on sepsis case finding and improving blood culture utilisation and diagnostics.


Asunto(s)
Antiinfecciosos , Sepsis , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias , Niño , Preescolar , Estudios Transversales , Atención a la Salud , Humanos , Nigeria/epidemiología , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico , Sepsis/epidemiología
20.
Arch Microbiol ; 204(6): 294, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35507075

RESUMEN

There is a need for new natural products with antimicrobial activity to treat multidrug resistant bacteria that can cause human illness. Some of them are foodborne pathogens. Two different Gram-negative psychrotrophic strains were isolated from healthy trout river samples (Salmo trutta). Based on phenotypic characterization, proteomics, genotyping and phylogenetic analyses of 16 rRNA gene, strains TCPS12 and TCPS13 were identified as Shewanella baltica and Pseudomonas fragi, respectively. Both of them produced an exopolysaccharide that showed antimicrobial activity against four foodborne pathogens. P. fragi supernatant (AS13) showed higher antimicrobial activity than S. baltica supernatant (AS12) against all tested pathogens. The stability of the antimicrobial activity of AS13 was assessed against Enterococcus faecalis ATCC 29212 under different conditions. This solution was stable when exposed for 30 min to temperatures ranging from 40 to 100 °C. In addition, it retained its activity within a pH range of 2-8 during 2 h of incubation, showing higher activity at pH 6. Serine proteases and α-amylase inactivated significantly the antimicrobial activity of AS13, suggesting that the active molecule could most likely be a glycoprotein. These products are interesting for their possible application as biopreservatives in the food industry.


Asunto(s)
Antiinfecciosos , Microbiología de Alimentos , Animales , Filogenia , Ríos , Trucha
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