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1.
Braz. j. biol ; 84: e249664, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345558

RESUMO

Abstract The impact of antibiotics on growth, cocoon production was assessed in addition to isolation and characterization of bacteria associated with silkworm gut of infected larvae. Larval rearing was maintained at recommended conditions of temperature and humidity. Silkworm larvae showing abnormal symptoms were collected from the control group and dissected for gut collection. Bacteria were isolated from the gut content by spreading on agar plates and incubated at 37 °C for 48 hrs. Bacterial identification and phylogenetic analysis were carried out by 16S rRNA gene sequencing. The isolated bacteria were subjected to antimicrobial susceptibility test (disc diffusion methods) by using Penicillin (10 µg/mL), Tetracycline (30 µg/mL), Amoxicillin (25 µg/mL), Ampicillin (10 µg/mL), and Erythromycin (15 µg/mL). All isolated strains showed positive results for the catalase test. We isolated and identified bacterial strains (n = 06) from the gut of healthy and diseased silkworm larvae. Based on the 16S rRNA gene sequence, isolated bacteria showed close relation with Serratia, Bacillus, and Pseudomonas spp. Notably, 83.3% of strains were resistant to Penicillin, Tetracycline, Amoxicillin, Ampicillin, and Erythromycin but 16.6% showed antibiotic susceptibility to the above-mentioned commonly used antibiotics. Silkworm larvae fed on penicillin-treated leaves showed significant improvement in larval weight, larval length, and cocoon production. Significantly higher larval weight (6.88g), larval length (5.84cm), and cocoon weight (1.33g) were recorded for larvae fed on leaves treated with penicillin as compared to other antibiotics. Isolated bacterial strains showed close relation with Serratia spp., Bacillus spp. and Pseudomonas spp.


Resumo O impacto dos antibióticos no crescimento e na produção do casulo foi avaliado, além do isolamento e caracterização das bactérias associadas ao intestino de larvas infectadas do bicho-da-seda. A criação das larvas foi mantida nas condições recomendadas de temperatura e umidade. As larvas do bicho-da-seda com sintomas anormais foram coletadas do grupo controle e dissecadas para coleta do intestino. As bactérias foram isoladas do conteúdo intestinal por espalhamento em placas de ágar e incubadas a 37° C durante 48 horas. A identificação bacteriana e a análise filogenética foram realizadas pelo sequenciamento do gene 16S rRNA. As bactérias isoladas foram submetidas a teste de sensibilidade antimicrobiana (métodos de difusão em disco) com penicilina (10 µg / mL), tetraciclina (30 µg / mL), amoxicilina (25 µg / mL), ampicilina (10 µg / mL) e eritromicina (15 µg / mL). Todas as cepas isoladas apresentaram resultados positivos para o teste da catalase. Isolamos e identificamos cepas bacterianas (n = 06) do intestino de larvas de bicho-da-seda saudáveis e doentes. Com base na sequência do gene 16S rRNA, as bactérias isoladas mostraram estreita relação com Serratia, Bacillus e Pseudomonas spp. Notavelmente, 83,3% das cepas eram resistentes a penicilina, tetraciclina, amoxicilina, ampicilina e eritromicina, mas 16,6% mostraram suscetibilidade aos antibióticos comumente usados mencionados acima. As larvas do bicho-da-seda alimentadas com folhas tratadas com penicilina apresentaram melhora significativa no peso larval, comprimento larval e produção de casulo. Peso larval significativamente maior (6,88g), comprimento larval (5,84cm) e peso do casulo (1,33g) foram registrados para larvas alimentadas com folhas tratadas com penicilina, em comparação com outros antibióticos. Cepas bacterianas isoladas mostraram estreita relação com Serratia spp., Bacillus spp. e Pseudomonas spp.


Assuntos
Animais , Bombyx , Antibacterianos/farmacologia , Filogenia , Bactérias/genética , RNA Ribossômico 16S/genética , Testes de Sensibilidade Microbiana , Larva
2.
Food Chem ; 398: 133910, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35973296

RESUMO

Riboflavin (Rf), an externally supplied nutrient, is highly photosensitive, and should be protected from sunlight once used in food and pharmaceutical manufacturing. The applications of encapsulated Rf have recently developed due to their therapeutic properties. In this study, the use of green silver nanoparticles (AgNPs) synthesized by Rosa damascena mill L. extract to control the encapsulation efficiency of Rf in potato starch was demonstrated for the first time. Starch/Rf, Starch/AgNPs/Rf and Starch/AgNPs nanocapsules were characterized by Fourier-transform infrared, field emission scanning electron microscopy, differential scanning calorimetry, and brunauer-Emmett-Teller techniques. The obtained results showed that the presence of AgNPs reduces Rf nanocapsules size (from 340 to 327 nm), increases the encapsulation efficiency (21.14 ± 0.62 to 92.52 ± 1.32 %) and improves the thermal stability, antibacterial and antioxidant activities. Moreover, UV-vis spectroscopy demonstrated the stronger association of AgNPs/Rf and AgNPs/Rf/Starch nanocapsules with BSA under physiological conditions.


Assuntos
Nanopartículas Metálicas , Nanocápsulas , Solanum tuberosum , Antibacterianos/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Riboflavina , Prata/química , Espectroscopia de Infravermelho com Transformada de Fourier , Amido , Difração de Raios X
3.
J Ethnopharmacol ; 300: 115738, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36165961

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Matayba oppositifolia (A. Rich.) Britton (commonly known as "huaya" or "palo huacax") is commonly utilized in traditional Mayan medicine for treating diarrhea and for canker and other sores. AIM OF THE STUDY: The aim of this study was to investigate the in-vitro antimicrobial activity of M. oppositifolia bark extracts against drug-susceptible and -resistant ESKAPE-E pathogens. In addition, the phytochemical composition of the best antibacterial extract was analyzed. MATERIALS AND METHODS: The bark extracts were prepared with different solvents, including water, n-hexane, ethyl acetate and methanol. These were tested against ESKAPE-E (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp., including Escherichia coli) strains using Resazurin Microtiter Assay. In addition, the composition of the most active extract was analyzed by GC-MS. RESULTS: The aqueous and organic bark extracts showed activity on drug-susceptible and -resistant ESKAPE-E microbes (MIC = 1000-31.25 µg/mL). The n-hexane bark extract was more active against the superbugs carbapenem-resistant K. pneumoniae (MIC = 500-31.25 µg/mL) and A. baumannii (MIC = 250-125 µg/mL). The GC-MS analysis of this extract allowed the identification of 12 phytochemicals as the potential antibacterial compounds. The major compounds identified were palmitic acid (1), friedelan-3-one (2) and 7-dehydrodiosgenin (3). CONCLUSION: The present study reveals the strong in-vitro antibacterial activity of the n-hexane extract from the bark of M. oppositifolia and demonstrates the potential of natural products as a source of antibacterial compounds or phytomedicines that are specifically effective against drug-resistant ESKAPE-E bugs. Additionally, our investigation contributes to the ethnopharmacological knowledge and reappraisal of Mayan medicinal flora, as well as supports the traditional use of the bark of the medicinal plant M. oppositifolia for the treatment of infectious diseases.


Assuntos
Antibacterianos , Plantas Medicinais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Carbapenêmicos/farmacologia , Escherichia coli , Hexanos , Klebsiella pneumoniae , Metanol/farmacologia , Testes de Sensibilidade Microbiana , Ácido Palmítico , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sapindaceae , Solventes/farmacologia , Água/farmacologia
4.
J Ethnopharmacol ; 300: 115687, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36084819

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Global interest in phytogenic feed additives as alternatives to antibiotics in feed has been spurred by the banning of antibiotic growth promoters by several countries. Suitable plant extracts for development of phytogenic feed additives should have therapeutic value and should also be safe. AIM OF STUDY: The aim of this study was to evaluate the antibacterial, antioxidant and anti-lipoxygenase activities as well as cytotoxicity of selected plant species used in poultry ethnomedicine in Zimbabwe. METHODS: Antibacterial activity was determined against three ATCC strains (Staphylococcus aureus, Escherichia coli, Salmonella Enteritidis) and two clinical strains isolated from chickens (Escherichia coli and Salmonella Gallinarum) using a two-fold serial microdilution assay. Qualitative antibacterial bioautography was also carried out using the ATCC strains. Antioxidant activities of crude acetone and methanol extracts were determined using free radical scavenging assays whilst anti-lipoxygenase activity was evaluated using a ferrous oxidation-xylenol orange (FOX) assay. Cytotoxicity was evaluated using a tetrazolium-based colorimetric assay (MTT assay) on Vero monkey kidney cells. RESULTS: Erythrina abyssinica had the best antibacterial activity against both ATCC strains and clinical strains with minimum inhibitory concentration (MIC) values ranging from 0.02 to 0.156 mg/ml. Aloe greatheadii, Adenia gummifera (leaves), Senna singueana and Aloe chabaudii had moderate activity against the poultry pathogens. Bioautography showed that all ten plant species have antibacterial activity against the tested microorganisms with E. abyssinica and S. singueana having prominent bands of inhibition against both Gram-negative and Gram-positive bacteria. The acetone extract of S. singueana and the methanol extract of Euphorbia matabelensis had the most powerful antioxidant activities with mean IC50 values of 1.43 µg/ml and 1.31 µg/ml respectively in the ABTS assay which were comparable with those of the positive controls (ascorbic acid and trolox). Bobgunnia madagascariensis, A. chabaudii, E. abyssinica and Tridactyle bicaudata extracts had reasonable antioxidant activity. The S. singueana extract had the most potent anti-lipoxygenase activity with a mean IC50 value of 1.72 µg/ml. The cytotoxicity results showed that only the acetone extracts of A. greatheadii and S. singueana were relatively safe at concentrations that were active against the tested microorganisms (selective index >1). Regarding anti-lipoxygenase activity, extracts of B. madagascariensis, S. singueana, T. bicaudata and E. matabelensis were more active than toxic (selective index >5) indicating anti-inflammatory potential. CONCLUSIONS: This study showed that S. singueana had a cocktail of therapeutic activity and supports further investigation of this plant species for development of phytogenic poultry feed additives. Other plant species with noteworthy biological activities include B. madagascariensis, E. abyssinica, A. greatheadii, T. bicaudata and E. matabelensis.


Assuntos
Antibacterianos , Antioxidantes , Acetona , Animais , Antibacterianos/toxicidade , Anti-Inflamatórios/toxicidade , Antioxidantes/toxicidade , Ácido Ascórbico , Galinhas , Escherichia coli , Radicais Livres , Medicina Tradicional , Metanol , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Aves Domésticas , Zimbábue
5.
Ann Lab Med ; 43(1): 45-54, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36045056

RESUMO

Background: Streptococcus pneumoniae is a serious pathogen causing various infections in humans. We evaluated the serotype distribution and antimicrobial resistance of S. pneumoniae causing invasive pneumococcal disease (IPD) after introduction of pneumococcal conjugate vaccine (PCV)13 in Korea and investigated the epidemiological characteristics of multidrug-resistant (MDR) isolates. Methods: S. pneumoniae isolates causing IPD were collected from 16 hospitals in Korea between 2017 and 2019. Serotyping was performed using modified sequential multiplex PCR and the Quellung reaction. Antimicrobial susceptibility tests were performed using the broth microdilution method. Multilocus sequence typing was performed on MDR isolates for epidemiological investigations. Results: Among the 411 S. pneumoniae isolates analyzed, the most prevalent serotype was 3 (12.2%), followed by 10A (9.5%), 34 (7.3%), 19A (6.8%), 23A (6.3%), 22F (6.1%), 35B (5.8%), 11A (5.1%), and others (40.9%). The coverage rates of PCV7, PCV10, PCV13, and pneumococcal polysaccharide vaccine (PPSV)23 were 7.8%, 7.8%, 28.7%, and 59.4%, respectively. Resistance rates to penicillin, ceftriaxone, erythromycin, and levofloxacin were 13.1%, 9.2%, 80.3%, and 4.1%, respectively. MDR isolates accounted for 23.4% of all isolates. Serotypes 23A, 11A, 19A, and 15B accounted for the highest proportions of total isolates at 18.8%, 16.7%, 14.6%, and 8.3%, respectively. Sequence type (ST)166 (43.8%) and ST320 (12.5%) were common among MDR isolates. Conclusions: Non-PCV13 serotypes are increasing among invasive S. pneumoniae strains causing IPD. Differences in antimicrobial resistance were found according to the specific serotype. Continuous monitoring of serotypes and antimicrobial resistance is necessary for the appropriate management of S. pneumoniae infections.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/farmacologia , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/genética , Vacinas Conjugadas/farmacologia
6.
Braz. j. biol ; 83: e243332, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345537

RESUMO

Abstract The present study was aimed to manifest the antibacterial and antifungal activity of methanolic extracts of Salix alba L. against seven Gram-positive and Gram-negative bacterial pathogens e.g. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) and Neisseria gonorrhoeae and three fungal isolates from the air such as Aspergillus terreus, A. ornatus, and Rhizopus stolonifer. Two different serotypes of S. aureus and E. coli were used. The agar well-diffusion method results showed the dose-dependent response of plant extracts against bacterial and fungal strains while some organisms were found resistant e.g. E. coli (1), S. sonnei, A. terreus and R. stolonifer. The highest antibacterial activity was recorded at 17.000±1.732 mm from 100 mg/mL of leaves methanolic extracts against S. pyogenes while the activity of most of the pathogens decreased after 24 h of incubation. The highest antifungal activity was reported at 11.833±1.0 mm against A. ornatus at 50 mg/mL after 48 h of the incubation period. These experimental findings endorse the use of S. alba in ethnopharmacological formulations and suggest the use of methanolic extracts of the said plant to develop drugs to control the proliferation of resistant disease causing pathogenic microbes.


Resumo O presente estudo teve como objetivo manifestar a atividade antibacteriana e antifúngica de extratos metanólicos de Salix alba L. contra sete patógenos bacterianos Gram-positivos e Gram-negativos. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) e Neisseria gonorrhoeae e três isolados de fungos do ar, como Aspergillus terreus, A. ornatus, e Rhizopus stolonifer. Dois sorotipos diferentes de S. aureus e E. coli foram usados. Os resultados do método de difusão em ágar mostraram a resposta dependente da dose de extratos de plantas contra cepas de bactérias e fungos, enquanto alguns organismos foram considerados resistentes, e.g. E. coli (1), S. sonnei, A. terreus e R. stolonifer. A maior atividade antibacteriana foi registrada em 17.000 ± 1.732 de 100 mg/mL de extratos metanólicos de folhas contra S. pyogenes, enquanto a atividade da maioria dos patógenos diminuiu após 24 h de incubação. A maior atividade antifúngica foi relatada em 11,833 ± 1,0 contra A. ornatus a 50 mg/mL após 48 h do período de incubação. Esses achados experimentais endossam o uso de S. alba em formulações etnofarmacológicas e sugerem o uso de extratos metanólicos da referida planta para o desenvolvimento de fármacos que controlem a proliferação de doenças resistentes que causam micróbios patogênicos.


Assuntos
Salix , Antifúngicos/farmacologia , Aspergillus , Rhizopus , Staphylococcus aureus , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Metanol , Escherichia coli , Antibacterianos/farmacologia
7.
Braz. j. biol ; 83: e247016, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339416

RESUMO

Abstract Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Resumo Pheretima posthuma (Vaillant, 1868), uma minhoca nativa do Paquistão e sudeste da Ásia, tem ampla utilização em processos de vermicompostagem e biorremediação. Neste estudo, o fluido celômico de P. posthuma (PCF) e a pasta corporal (PBP) foram avaliados como agente antibacteriano contra cinco isolados clínicos Gram-positivos e quatro Gram-negativos resistentes à ampicilina (AMP). O efeito antibacteriano de diferentes doses (ou seja, 25-100 µg / ml) de PCF e PBP juntamente com AMP e azitromicina (AZM) (controles negativo e positivo, respectivamente) foi observado por meio de métodos de difusão em disco e microdiluição. Todos os nove isolados clínicos foram notados como resistentes a AMP e sensíveis a AZM. Os efeitos antibacterianos de PCF e PBP foram dependentes da dose e a zona de inibição (ZI) contra todos os isolados clínicos foi entre 23,4 ± 0,92 a 0 ± 00 mm. O perfil de sensibilidade do PCF e PBP contra isolados clínicos foi observado como 44,44% e 55,56%, respectivamente. Tanto o PCF quanto o PBP mostraram ação bacteriostática (BTS) contra S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Além disso, o potencial BTS cumulativo de PCF e PBP contra todos os isolados foi de 66,67% e 55,56%, respectivamente. Os MICs de PCF e PBP variaram de 50-200 µg / ml contra isolados selecionados. As curvas de crescimento bacteriano indicaram que o PCF e o PBP inibiram o crescimento de todos os isolados em suas concentrações específicas de MIC. No entanto, PBP tem melhor potencial antibacteriano em comparação com PCF contra isolados selecionados. Portanto, conclui-se que tanto o PCF quanto o PBP de P. posthuma possuem potencial antibacteriano e BTS contra isolados clínicos resistentes à ampicilina. Esse organismo pode ser considerado como uma segunda escolha de agentes antibacterianos e pode ainda ser utilizado nas indústrias farmacêuticas para a fabricação de novos medicamentos por meio da prospecção de agentes com potencial bioativo.


Assuntos
Animais , Oligoquetos , Staphylococcus aureus , Testes de Sensibilidade Microbiana , Ampicilina/farmacologia , Antibacterianos/farmacologia
8.
Braz. j. biol ; 83: e245585, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339413

RESUMO

Abstract Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence analysis. Finally, the isolates were identified as B. cereus accession number LC538271and K. pneumoniae accession number MT078679. Analysis of bacterial extract S20 through GC-MS indicated the presence of 8 compounds of diverse nature and structure. Present study suggests that wastes of pharmaceutical and poultry feed industry may have antibiotic producing bacteria. These bacteria could be utilized for the production of antibiotics. B. cereus and K. pneumoniae isolated from wastes of poultry feed and pharmaceutical industries have the potential to produce antibiotics and could be used to control the microbial growth.


Resumo Muitos microrganismos do solo, ou seja, bactérias e fungos produzem metabólitos secundários chamados antibióticos. Eles são usados ​​para tratamento de algumas doenças bacterianas, fúngicas e protozoárias em humanos. Há necessidade de isolamento de um amplo espectro de antibióticos de microrganismos devido ao surgimento de resistência aos antibióticos. No presente estudo, duas bactérias produtoras de antibióticos, Klebsiella pneumoniae e Bacillus cereus, foram isoladas da indústria farmacêutica e de ração avícola de Hattar, Haripur, Paquistão. Um total de 10 amostras de resíduos foi coletado de diferentes indústrias (mármore, ghee, sabão, mineral, aço, ração para aves, farmacêutica, Qarshi, cosmética e vidro). Trinta e três cepas bacterianas foram isoladas de resíduos industriais dessas dez diferentes indústrias. Quatorze das 33 cepas bacterianas exibiram atividades antimicrobianas contra pelo menos um dos micróbios de teste considerados neste estudo, incluindo Escherchia coli, Staphylococcus aureus e Salmonella typhi. As bactérias foram isoladas pela técnica de placa de diluição em série padrão. A caracterização morfológica dos isolados foi feita por coloração de gram. Nove isolados bacterianos de 14 foram inicialmente identificados como B. cereus e cinco como K. pneumoniae por meio de caracterização bioquímica. As atividades antibacterianas foram testadas pelo método de difusão em poço. O número máximo de bactérias produtoras de antibióticos foi isolado da indústria farmacêutica e de ração avícola com base nos resultados da triagem primária, os isolados mais potenciais S9, S19, S20, S22 e S23 foram selecionados para a triagem secundária. A atividade máxima contra E. coli e S. aureus foi registrada pelo isolado bacteriano S19, ou seja, zonas de inibição de 6,5 mm e 9 mm, enquanto S20 mostrou zonas de 7,5 mm e 6 mm, respectivamente. A identificação molecular foi realizada com base na análise da sequência 16S rRNA. Finalmente, os isolados foram identificados como B. cereus número de acesso LC538271 e K. pneumoniae número de acesso MT078679. A análise do extrato bacteriano S20 por meio de GC-MS indicou a presença de oito compostos de natureza e estrutura diversas. O presente estudo sugere que resíduos da indústria farmacêutica e de ração para aves podem conter bactérias produtoras de antibióticos. Essas bactérias podem ser utilizadas para a produção de antibióticos B. cereus e K. pneumoniae isolados de resíduos de rações de aves e indústrias farmacêuticas têm potencial para produzir antibióticos e podem ser usados ​​para controlar o crescimento microbiano.


Assuntos
Humanos , Staphylococcus aureus , Resíduos Industriais , RNA Ribossômico 16S , Extratos Vegetais , Testes de Sensibilidade Microbiana , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia
9.
Braz. j. biol ; 83: e239323, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339341

RESUMO

Abstract The β-lactam/lactamase inhibitors (BLBLIs) combination drugs are considered an effective alternative to carbapenems. However, there is a growing concern that the increased use of BLBLIs may lead to increased resistance. This study determined the temporal association between the consumption of BLBLI and the antimicrobial resistance in Gram-negative bacteria. In this retrospective study, electronic data on the Gram-negative bacterial isolates, including A. baumannii, P. aeruginosa, E. coli, and K. pneumoniae from in-patients and susceptibility testing results were retrieved from the medical records of the clinical laboratory. A linear regression and cross-correlation analysis were performed on the acquired data. Increasing trends (p<0.05) in the consumption of BIBLI and carbapenem with a median use of 27.68 and 34.46 DDD/1000 PD per quarter were observed, respectively. A decreased trend (p=0.023) in the consumption of fluoroquinolones with a median use of 29.13 DDD/1000 PD per quarter was observed. The resistance rate of K. pneumoniae was synchronized with the BIBLI and carbapenem consumptions with a correlation coefficient of 0.893 (p=0.012) and 0.951 (p=0.016), respectively. The cross-correlation analysis against the consumption of BIBLI and meropenem resistant K. pneumoniae was peaked at 0-quarter lag (r=951, p=0.016). There was an increasing trend in the consumption of BLBLI and carbapenems. The increasing trend in the rates of resistance to piperacillin/tazobactam, in line with the increasing consumption of BLBLI, suggests that BLBLI has to be used with caution and cannot be directly considered as a long-term alternative to carbapenems.


Resumo Os medicamentos combinados de β-lactâmicos / inibidores da lactamase (BLBLIs) são considerados uma alternativa eficaz aos carbapenêmicos. No entanto, existe uma preocupação crescente de que o aumento do uso de BLBLIs pode levar ao aumento da resistência. Este estudo determinou a associação temporal entre o consumo de BLBLI e a resistência antimicrobiana em bactérias gram-negativas. Neste estudo retrospectivo, os dados eletrônicos sobre as bactérias gram-negativas isoladas, incluindo A. baumannii, P. aeruginosa, E. coli e K. pneumoniae de pacientes internados e os resultados dos testes de suscetibilidade foram recuperados dos registros médicos do laboratório clínico. Uma regressão linear e análise de correlação cruzada foram realizadas nos dados adquiridos. Foram observadas tendências crescentes (p < 0,05) no consumo de BIBLI e carbapenem com uma mediana de uso de 27,68 e 34,46 DDD/1000 PD por trimestre, respectivamente. Foi observada uma tendência de diminuição (p = 0,023) no consumo de fluoroquinolonas com uma mediana de uso de 29,13 DDD/1000 PD por trimestre. A taxa de resistência de K. pneumoniae foi sincronizada com os consumos de BIBLI e carbapenem com coeficiente de correlação de 0,893 (p = 0,012) e 0,951 (p = 0,016), respectivamente. A análise de correlação cruzada contra o consumo de BIBLI e K. pneumoniae resistente ao meropenem atingiu o pico no intervalo de 0 quarto (r = 951, p = 0,016). Houve uma tendência de aumento no consumo de BLBLI e carbapenêmicos. A tendência crescente nas taxas de resistência a piperacilina/tazobactam, em linha com o consumo crescente de BLBLI, sugere que BLBLI deve ser usado com cautela e não pode ser considerado diretamente como alternativa de longo prazo aos carbapenêmicos.


Assuntos
Humanos , Infecções por Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas/epidemiologia , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Escherichia coli , Bactérias Gram-Negativas
10.
Braz. j. biol ; 83: e242703, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285636

RESUMO

Abstract Oral diseases caused by various microorganisms are common around the world. Scientific research has now been focusing on novel medicines to overcome bacterial resistance and antibiotics side effects; therefore, the current study was designed to assess the efficacy of certain antibiotics, toothpaste, and medicinal plant extracts (Ajuga bracteosa and Curcuma longa) versus the bacterial pathogens isolated from the human oral cavity. A total of 130 samples were collected from Khyber Teaching Hospital Peshawar, Pakistan, among those 27 species isolated, and eight bacterial species were identified from the samples. Among all the bacterial species, Staphylococcus aureus (29.62%) and Proteus mirabilis (22.2%) were found to be more prevalent oral pathogens. In comparison, the least pervasive microbes were Proteus vulgaris, Shigella sonnei, Escherichia coli and Aeromonas hydrophila. The study also suggested that dental problems were more prevalent in males (41-50 years of age) than females. Among the eight antibiotics used in the study, the most promising results were shown by Foxicillin against A. hydrophila. The survey of TP1 revealed that it showed more potent antagonist activity against Proteus vulgaris as compared TP2 and TP3 that might be due to the high content of fluoride. The Curcuma longa showed more significant activity than Ajuga bracteosa (Stem, leaves and root) extracts. The data obtained through this study revealed that antibiotics were more effective for oral bacterial pathogens than toothpaste and plant extracts which showed moderate and low activity, respectively. Therefore, it is suggested that the active compounds in individual medicinal plants like Curcuma longa and Ajuga bracteosa could replace the antibiotics when used in daily routine as tooth cleansers or mouth rinses.


Resumo As doenças bucais causadas por vários microrganismos são comuns em todo o mundo. A pesquisa científica agora tem se concentrado em novos medicamentos para superar a resistência bacteriana e os efeitos colaterais dos antibióticos; portanto, o presente estudo foi desenhado para avaliar a eficácia de certos antibióticos, pasta de dente e extratos de plantas medicinais (Ajuga bracteosa e Curcuma longa) contra os patógenos bacterianos isolados da cavidade oral humana. No total, 130 amostras foram coletadas do Khyber Teaching Hospital Peshawar, Paquistão, entre essas, 27 espécies foram isoladas e oito espécies bacterianas foram identificadas a partir das amostras. Entre todas as espécies bacterianas, Staphylococcus aureus (29.62%) e Proteus mirabilis (22.2%) foram os patógenos orais mais prevalentes. Em comparação, os micróbios menos difundidos foram Proteus vulgaris, Shigella sonnei, Escherichia coli e Aeromonas hydrophila. O estudo também sugeriu que os problemas dentários eram mais prevalentes em homens (41-50 anos de idade) do que em mulheres. Entre os oito antibióticos usados ​​no estudo, os resultados mais promissores foram mostrados pelo Foxicillin contra A. hydrophila. A pesquisa de TP1 revelou que ele mostrou atividade antagonista mais potente contra Proteus vulgaris em comparação a TP2 e TP3, o que pode ser devido ao alto teor de flúor. A Curcuma longa apresentou atividade mais significativa em relação aos extratos de Ajuga bracteosa (caule, folhas e raiz). Os dados obtidos neste estudo revelaram que os antibióticos foram mais eficazes para os patógenos bacterianos orais do que os dentifrícios e os extratos vegetais que apresentaram atividade moderada e baixa, respectivamente. Portanto, sugere-se que os compostos ativos em plantas medicinais individuais como Curcuma longa e Ajuga bracteosa possam substituir os antibióticos quando usados ​​na rotina diária como limpadores de dentes ou enxaguatórios bucais.


Assuntos
Humanos , Masculino , Feminino , Cremes Dentais , Fluoretos , Paquistão , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Antibacterianos
11.
Braz. j. biol ; 83: e245807, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285613

RESUMO

Abstract Linum usitatissimum L is a widely used traditionally for multiple ailments. The present research was carried out to explore the antimicrobial, and anti-biofilm activity of crude extract of Linum usitatissimum L (Lu. Cr). Phytochemical and proximate analyses were performed. The bandages of diabetic foot patients were collected from the various hospitals. The bandages were cultured to isolate the bacterial strains present on it. The disc diffusion method was used to identify the antimicrobial potential whereas the minimum inhibitory concentration of the Lu.Cr were also determined. Proximate analysis confirms moisture content 8.33%, ash content 4.33%, crude protein 21.20%, crude fat 49.2% and crude fiber 5.63%. It was revealed that Gram-positive bacteria are most prevalent among all study groups. Lu.Cr possess significant bactericidal potential against S. aureus among all other microbes. Owing to this potential, linseed coated bandages can be used alternatively for the treatment of diabetic foot.


Resumo Linum usitatissimum L é amplamente utilizado tradicionalmente para doenças múltiplas. O presente trabalho foi realizado para explorar a atividade antimicrobiana e antibiofilme do extrato bruto de Linum usitatissimum L (Lu.Cr). Foram realizadas análises fitoquímicas e aproximadas. As ataduras de pacientes diabéticos com pé foram recolhidas nos vários hospitais. As bandagens foram cultivadas para isolar as cepas bacterianas presentes nas mesmas. O método de difusão em disco foi utilizado para identificar o potencial antimicrobiano e a concentração inibitória mínima do Lu.Cr também foi determinada. A análise aproximada confirma o teor de umidade 8,33%, teor de cinzas 4,33%, proteína bruta 21,20%, gordura bruta 49,2% e fibra bruta 5,63%. Foi revelado que as bactérias Gram-positivas são mais prevalentes entre todos os grupos de estudo. Lu.Cr possui potencial bactericida significativo contra S. aureus entre todos os outros micróbios. Devido a esse potencial, as ligaduras revestidas com linhaça podem ser utilizadas alternativamente para o tratamento do pé diabético.


Assuntos
Humanos , Pé Diabético/tratamento farmacológico , Linho , Diabetes Mellitus , Staphylococcus aureus , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Biofilmes , Metanol
12.
J Enzyme Inhib Med Chem ; 38(1): 36-50, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36305289

RESUMO

The increasing resistance of fungi to conventional antifungal drugs has prompted worldwide the search for new compounds. In this work, we investigated the antifungal properties of acylated Temporin L derivatives, Pent-1B and Dec-1B, against Candida albicans, including the multidrug-resistant strains. Acylated peptides resulted to be active both on reference and clinical strains with MIC values ranging from 6.5 to 26 µM, and they did not show cytotoxicity on human keratinocytes. In addition, we also observed a synergistic or additive effect with voriconazole for peptides Dec-1B and Pent-1B through the checkerboard assay on voriconazole-resistant Candida strains. Moreover, fluorescence-based assays, NMR spectroscopy, and confocal microscopy elucidated a potential membrane-active mechanism, consisting of an initial electrostatic interaction of acylated peptides with fungal membrane, followed by aggregation and insertion into the lipid bilayer and causing membrane perturbation probably through a carpeting effect.


Assuntos
Antifúngicos , Candida albicans , Farmacorresistência Fúngica Múltipla , Humanos , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Voriconazol/farmacologia
13.
J Hazard Mater ; 442: 130112, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303348

RESUMO

Rifampicin (RIF) resistance imposes a challenge on the antimicrobial treatment of pathogen infections. Figuring out the development mechanism of RIF resistance is critical to improving antimicrobial therapy strategy in clinics and biological treatment strategy of RIF polluted sewage in environmental engineering. The RIF resistance development of Staphylococcus aureus (S. aureus) with exposure to RIF at sub-inhibitory concentrations was comprehensively investigated via genomic and transcriptomic approaches in this study. RIF minimal inhibitory concentration (MIC) for S. aureus rapidly increased from 0.032 to 256 mg/L. Membrane permeability decrease, biofilm formation enhancement, and ROS production increase associated with RIF resistance were observed in RIF-induced strains. Through comparative genomic analysis, mutations in rpoB and rpoC were considered to be associated with RIF resistance in S. aureus mutants. Pan-genome-wide single-nucleotide variant analysis indicated that mutations at rpoB-1412, rpoB-1451, and rpoB-1457 were prevalent in 13849 public genomes of S. aureus, while mutations at rpoB-2256, and rpoC-3092 were first discovered in this study. The panorama of adaptative alteration of cellular physiological processes was observed via transcriptomic analysis. The oxidation pressure responses, metabolism, transporters, virulence factors, and multiple steps of DNA and RNA machinery were found to be perturbed by RIF in S. aureus.


Assuntos
Rifampina , Staphylococcus aureus , Rifampina/farmacologia , Staphylococcus aureus/genética , Farmacorresistência Bacteriana/genética , Transcriptoma , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/farmacologia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Mutação , Genômica , Proteínas de Bactérias/genética
14.
Int J Food Microbiol ; 384: 109981, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36306546

RESUMO

Poultry meat has been a vehicle of antibiotic resistant bacteria and genes. Yet, the diversity of selective pressures associated with their maintenance in the poultry-production chain remains poorly explored. We evaluated the susceptibility of Enterococcus spp. from chicken meat collected 20 years apart to antibiotics, metals, acidic pH and peracetic acid-PAA. Contemporary chicken-meat samples (n = 53 batches, each including a pool of neck skin from 10 single carcasses) were collected in a slaughterhouse facility using PAA as disinfectant (March-August 2018, North of Portugal). Broilers were raised in intensive farms (n = 29) using CuSO4 and organic acids as feed additives. Data were compared with that of 67 samples recovered in the same region during 1999-2001. All 2018 samples had multidrug resistant-MDR isolates, with >45 % carrying Enterococcus faecalis, Enterococcus faecium or Enterococcus gallinarum resistant to tetracycline, erythromycin, ampicillin, quinupristin-dalfopristin, ciprofloxacin, chloramphenicol or aminoglycosides. Resistance rates were similar (P > 0.05) to those of 1999-2001 samples for all but five antibiotics. The decrease of samples carrying vancomycin-resistant isolates from 46 % to 0 % between 1999-2001 and 2018 was the most striking difference. Isolates from both periods were similarly susceptible to acid pH [minimum-growth pH (4.5-5.0), minimum-survival pH (3.0-4.0)] and to PAA (MIC90 = 100-120 mg/L/MBC90 = 140-160 mg/L; below concentrations used in slaughterhouse). Copper tolerance genes (tcrB and/or cueO) were respectively detected in 21 % and 4 % of 2018 and 1999-2001 samples. The tcrB gene was only detected in E. faecalis (MICCuSO4 > 12 mM), and their genomes were compared with other international ones of chicken origin (PATRIC database), revealing a polyclonal population and a plasmid or chromosomal location for tcrB. The tcrB plasmids shared diverse genetic modules, including multiple antimicrobial resistance genes (e.g. to tetracyclines, chloramphenicol, macrolide-lincosamide-streptogramin B-MLSB, aminoglycosides, bacitracin, coccidiostats). When in chromosome, the tcrB gene was co-located closely to merA (mercury) genes. Chicken meat remains an important vehicle of MDR Enterococcus spp. able to survive under diverse stresses (e.g. copper, acid) potentially contributing to these bacteria maintenance and flux among animal-environment-humans.


Assuntos
Galinhas , Enterococcus faecium , Animais , Humanos , Galinhas/microbiologia , Aves Domésticas , Antibacterianos/farmacologia , Cobre/farmacologia , Testes de Sensibilidade Microbiana , Enterococcus , Aminoglicosídeos , Cloranfenicol , Farmacorresistência Bacteriana/genética , Carne/microbiologia
15.
J Colloid Interface Sci ; 631(Pt A): 165-180, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36375299

RESUMO

Silver nanoparticles (AgNPs) have found widespread commercial applications due to their unique physical and chemical properties. However, their relatively poor stability remains a main problem. An ideal way to improve the stability of AgNPs is not only to endow colloidal stability to individual nanoparticles but also to protect them from environmental factors that induce their agglomeration, like variation of ionic strength and pH, presence of macromolecules, etc. Mesoporous calcium carbonate vaterite crystals (CaCO3 vaterite) have recently attracted significant attention as inexpensive and biocompatible carriers for the encapsulation and controlled release of both drugs and nanoparticles. This work aimed to develop an approach to load AgNPs into CaCO3 vaterite without affecting their properties. We focused on improving the colloidal stability of AgNPs by using different capping agents, and understanding the mechanism behind AgNPs loading and release from CaCO3 crystals. Various methods were applied to study the AgNPs and CaCO3 crystals loaded with AgNPs (CaCO3/AgNPs hybrids), such as scanning and transmission electron microscopy, X-ray diffraction, infrared and mass spectrometry. The results demonstrated that polyvinylpyrrolidone and positively charged diethylaminoethyl-dextran can effectively keep the colloidal stability of AgNPs during co-precipitation with CaCO3 crystals. CaCO3/AgNPs hybrids composed of up to 4 % weight content of nanoparticles were produced, with the loading mechanism being well-described by the Langmuir adsorption model. In vitro release studies demonstrated a burst release of stable AgNPs at pH 5.0 and a sustained release at pH 7.5 and 9.0. The antibacterial studies showed that these hybrids are effective against Escherichia coli, methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa, three important bacteria responsible for nosocomial infections. The developed approach opens a new way to stabilise, protect, store and release AgNPs in a controlled manner for their use as antimicrobial agents.


Assuntos
Nanopartículas Metálicas , Staphylococcus aureus Resistente à Meticilina , Prata/química , Nanopartículas Metálicas/química , Carbonato de Cálcio/química , Antibacterianos/farmacologia , Antibacterianos/química , Escherichia coli , Testes de Sensibilidade Microbiana
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121909, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36170776

RESUMO

For effective treatment, it is crucial to identify the infecting bacterium at the species level and to determine its antimicrobial susceptibility. This is especially true now, when numerous bacteria have developed multidrug resistance to most commonly used antibiotics. Currently used methods need âˆ¼ 48 h to identify a bacterium and determine its susceptibility to specific antibiotics. This study reports the potential of using infrared spectroscopy with machine learning algorithms to identify E. coli isolated directly from patients' urine while simultaneously determining its susceptibility to antibiotics within âˆ¼ 40 min after receiving the patient's urine sample. For this goal, 1,765 E. coli isolates purified directly from urine samples were collected from patients with urinary tract infections (UTIs). After collection, the samples were tested by infrared microscopy and analyzed by machine learning. We achieved success rates of âˆ¼ 96% in isolate level identification and âˆ¼ 84% in susceptibility determination.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Humanos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Espectrofotometria Infravermelho , Aprendizado de Máquina , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia
17.
J Infect Chemother ; 29(1): 26-32, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36100144

RESUMO

BACKGROUND: Several carbapenemases have been identified globally in Enterobacteriaceae. In Japan, IMP-type carbapenemase is the most prevalent, although cases of carbapenemase-producing Enterobacteriaceae (CPE) bacteremia are still scarce. The present case series and literature review aimed to elucidate the clinical characteristics and treatment strategies for IMP-type CPE bacteremia. METHODS: Clinical data on pediatric cases of IMP-type CPE bacteremia at the Tokyo Metropolitan Children's Medical Center between 2010 and 2020 were collected, and a review of past studies of IMP-type CPE bacteremia has been provided. RESULTS: Five pediatric episodes of IMP-type CPE bacteremia were identified. Our review of previous literature on IMP-type CPE bacteremia revealed 24 adult patients, but no pediatric patients. All 29 cases had underlying diseases, and 23 (79%) received combination therapy. The median duration of antibiotic therapy was 14 days (interquartile range: 9-14 days). The overall mortality rate was 38% (11/29). The mortality rates associated with monotherapy and combination therapy were 67% (4/6) and 30% (7/23), respectively. CONCLUSIONS: We report the first case series of IMP-type CPE bacteremia in children. Our review of past studies suggests that combination therapy might lead to better survival outcomes in patients with IMP-type CPE bacteremia. Further research is needed to establish an optimal treatment strategy for IMP-type CPE bacteremia.


Assuntos
Bacteriemia , Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Adulto , Criança , Humanos , Inosina Monofosfato , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/tratamento farmacológico , beta-Lactamases , Enterobacteriaceae , Bacteriemia/tratamento farmacológico , Proteínas de Bactérias , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana
18.
J Infect Chemother ; 29(1): 87-89, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36162644

RESUMO

Thermothelomyces thermophila (formerly Myceliophthora thermophila) is usually found in soil and specifically compost as an environmental dematiaceous fungus. Here, we report the first case of invasive pulmonary infection caused by T. thermophila in a pediatric patient with acute lymphoblastic leukemia. T. thermophila was serially cultured from bronchoalveolar lavage (BAL) fluid and sputum samples obtained from this patient with respiratory symptoms. The patient received antifungal treatment with liposomal amphotericin B (160 mg daily) and itraconazole (200 mg daily) combination therapy, but she died. By the antifungal susceptibility testing, low minimum inhibitory concentrations (MIC) were observed for itraconazole (MIC 0.06 µg/mL), voriconazole (MIC 0.12 µg/mL), and posaconazole (MIC 0.03 µg/mL) but high MIC was observed with amphotericin B (MIC 4.0 µg/mL). Since T. thermophila is usually found in the environment, it can be considered as a contaminant and may cause difficulties in diagnosis. Therefore, it is necessary to confirm the potential of pathogen through repeated culture and to conduct an antifungal susceptibility testing to find a suitable antifungal agent.


Assuntos
Antifúngicos , Pneumonia , Feminino , Humanos , Criança , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Itraconazol/farmacologia , Itraconazol/uso terapêutico , Voriconazol/farmacologia , Testes de Sensibilidade Microbiana
19.
J Infect Chemother ; 29(1): 82-86, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36162647

RESUMO

An 81-year-old man was admitted to our hospital because of fever and malaise that had persisted for 3 months. The patient had undergone two aortic valve replacements, 10 and 5 years previously, because of aortic valve regurgitation and infectious endocarditis. He also had had asymptomatic Mycobacterium abscessus complex (MABC) pulmonary disease for the two previous years. Contrast-enhanced computed tomography showed a mediastinal abscess and an ascending aortic aneurysm. Mycobacterium abscessus subsp. massiliense was cultured from his blood, suggesting the aortic aneurysm was secondary to infection of an implanted device. After enlargement over only a few days, a leakage of contrast medium to the mediastinal abscess was found on computed tomography. The patient was diagnosed with rupture of an infectious aortic aneurysm, and emergency aortic replacement and drainage of the mediastinal abscess were successful. The patient was treated with several antibiotics, including meropenem, amikacin, and clarithromycin, and his general condition improved. Cultures from both the mediastinal abscess and a pericardial patch that was placed at the time of surgery 5 years previously revealed MABC. In our case, the infected aortic aneurysm most likely resulted from MABC pulmonary disease rather than from previous intraoperative contamination. This route of infection is rare. Physicians should be aware of the possibility of dissemination and subsequent infection of implants related to MABC pulmonary disease.


Assuntos
Aneurisma Aórtico , Pneumopatias , Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Masculino , Humanos , Idoso de 80 Anos ou mais , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Abscesso , Claritromicina/uso terapêutico , Antibacterianos/uso terapêutico , Pneumopatias/microbiologia , Testes de Sensibilidade Microbiana
20.
Microbiol Res ; 266: 127246, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36327661

RESUMO

The emergence of antibiotic resistance among animal farms impels the development of novel antimicrobials or strategies for agri-food production. The combinational use of agents to achieve a synergistic antimicrobial effect provides many advantages such as dosage reduction, shortened treatment time, and avoidance of antimicrobial resistance. In this study, we evaluated the killing efficacy of single agent or combinational use of three antimicrobials, including cinnamon oil, encapsulated curcumin and zinc oxide nanoparticles (ZnO NPs), against a leading foodborne pathogen Campylobacter jejuni. We then investigated the antimicrobial mechanism using whole transcriptome sequencing analysis (RNA-Seq). The single-agent treatment of cinnamon oil, encapsulated curcumin, or ZnO NPs showed a significant antimicrobial effect against C. jejuni by generating more than 8-log reduction within 3 h. The transcriptional signatures of C. jejuni in response to these agents varied, indicating that these agents shared distinct mechanisms of action and were likely to generate synergistic effects. Cinnamon oil affected the integrity of cell membrane, which might lead to an increase in cell permeability. Encapsulated curcumin and ZnO NPs disrupted bacterial outer membranes and cell membranes against the same membrane protein targets. The combinational use of these agents showed synergistic antimicrobial effects and distinct mechanisms of action compared to single treatment. The combination of cinnamon oil and encapsulated curcumin provoked the expression of cellular signaling, but repressed the chemotaxis-associated genes. The antimicrobial resistance associated genes showed a low expression level in the combination of encapsulated curcumin and ZnO NPs. The tri-combination treatment systematically overexpressed genes involved in the amino acid synthesis, protein translation, and membrane protein synthesis. This study provides new insights in combating Campylobacter with minimizing the development of antimicrobial resistance in long-term usage.


Assuntos
Campylobacter jejuni , Curcumina , Nanopartículas , Óxido de Zinco , Animais , Campylobacter jejuni/genética , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Curcumina/farmacologia , Sequenciamento Completo do Exoma , Antibacterianos/farmacologia , Antibacterianos/química , Proteínas de Membrana , Testes de Sensibilidade Microbiana
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