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1.
Antibiotics (Basel) ; 12(11)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37998803

RESUMEN

Currently, biofilm-forming bacteria are difficult to treat by conventional antibiotic therapy and are, thus, becoming a clinical and epidemiological problem worldwide. Medicinal plants have been identified as novel alternative treatments due to their therapeutic and antimicrobial effects. In this context, the present study aimed to determine the total phenolic content, antioxidant capacity, and antimicrobial and anti-biofilm potential of nine extracts of Hymenaea courbaril (Fabaceae), popularly known as Jatobá. Furthermore, extracts that exhibited biofilm inhibitory activity against S. aureus (ATCC 25923) were selected for UPLC-HRMS/MS chemical analysis. Our results showed a high total phenolic content, mainly in the stem bark extract, and that the plant is rich in compounds with antioxidant activity. In the anti-biofilm analysis, leaf extracts stood out in comparison with chloramphenicol, with inhibition percentages of 78.29% and 78.85%, respectively. Through chemical analysis by UPLC-HRMS/MS, chrysoeriol-7-O-neohesperidoside, isorhamnetin-3-O-glucoside, and 3,7-di-O-methylquercetin were annotated for the first time in the leaves of H. courbaril. Therefore, these results showed the potential use of H. courbaril as an antioxidant and point to its use in antimicrobial therapy with an anti-biofilm effect.

2.
Curr Pharm Biotechnol ; 20(5): 433-444, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30963968

RESUMEN

BACKGROUND: Currently, the treatment of infectious diseases has not always been successful due to the emergence of microbial resistance worldwide. OBJECTIVES: This study aimed to evaluate the antioxidant activity, content of total phenolic compounds and flavonoids, antifungal potential and antibacterial action of six medicinal plants found in the Cerrado, leaf extracts of Boldo (Peumus boldus), Goiaba (Psidium guajava), Assa-Peixe (Vernonia polysphaera), Abacate (Persea americana), Eucalipto (Eucalyptus citriodora) and raw sap of Bálsamo (Jatropha multifida). METHODS: The antioxidant activity was also determined through the DPPH, ABTS and phosphomolybdenum assays. In addition, the total phenolic content and flavonoid dosage were analyzed using the Folin- Ciocalteu method and the aluminum chloride test, respectively. RESULTS: All extracts, except from Assa-Peixe, showed promising values against Staphylococcus aureus, with halos varying from 13-20 mm. Analysis of the minimum inhibitory concentration (MIC) values of the six medicinal plants revealed inhibitory activity of S. aureus, with concentrations varying from 3.12-12.5 mg/mL, which is a significant result considering that S. aureus is one of the main causes of hospital infections. CONCLUSION: In the analysis of the phytochemical profile, Goiaba contained the best yield of phenolic compounds and total flavonoids, as well as higher antioxidant activity by DPPH and phosphomolybdenum, demonstrating that this species contains antioxidant components that can sequester free radicals under in vitro conditions. Therefore, the crude extracts investigated are promising and their antibacterial and antioxidant actions should be thoroughly studied.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Flavonoides/aislamiento & purificación , Fenoles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Antibacterianos/farmacología , Antioxidantes/farmacología , Compuestos de Bifenilo/química , Brasil , Etnofarmacología , Flavonoides/farmacología , Pruebas de Sensibilidad Microbiana , Fenoles/farmacología , Picratos/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Staphylococcus aureus/efectos de los fármacos
3.
Mem Inst Oswaldo Cruz ; 106(3): 316-21, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21655819

RESUMEN

Human rhinoviruses (HRV) are usually associated with mild respiratory symptoms in children. However, some studies have found that HRV can cause severe disease, especially when the patient is co-infected with a second virus. In this study, 532 nasopharyngeal aspirates (NPAs) were collected over a nine-year period from children at the Clinics Hospital of Uberlândia. The collected NPAs were then tested for HRV RNA using the reverse transcription-polymerase chain reaction. Eighty-three specimens from children diagnosed with lower respiratory tract illness (LRTI) were positive for HRV RNA and were then tested for the presence of eight other respiratory viruses. A second virus was detected in 37.3% (31/83) of the samples. The most frequent clinical diagnosis was bronchiolitis, followed by other LRTI and then pneumonia. The frequency of severe disease in children infected with more than one virus was not significantly different from the frequency of severe disease in children infected with HRV alone. Children infected with both HRV and parainfluenza virus (1.5 m.o.) were significantly younger than those infected by HRV alone (5.0 m.o.) (p = 0.0454). Overall, these results suggest that infection with a second virus does not lead to a higher frequency of severe syndromes in children presenting with LRTI.


Asunto(s)
Nasofaringe/virología , ARN Viral/análisis , Infecciones del Sistema Respiratorio/virología , Rhinovirus/aislamiento & purificación , Adenoviridae/genética , Adenoviridae/aislamiento & purificación , Niño , Humanos , Virus ARN/genética , Virus ARN/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rhinovirus/genética , Estaciones del Año , Índice de Severidad de la Enfermedad
4.
Mem. Inst. Oswaldo Cruz ; 106(3): 316-321, May 2011. ilus
Artículo en Inglés | LILACS | ID: lil-589040

RESUMEN

Human rhinoviruses (HRV) are usually associated with mild respiratory symptoms in children. However, some studies have found that HRV can cause severe disease, especially when the patient is co-infected with a second virus. In this study, 532 nasopharyngeal aspirates (NPAs) were collected over a nine-year period from children at the Clinics Hospital of Uberlândia. The collected NPAs were then tested for HRV RNA using the reverse transcription-polymerase chain reaction. Eighty-three specimens from children diagnosed with lower respiratory tract illness (LRTI) were positive for HRV RNA and were then tested for the presence of eight other respiratory viruses. A second virus was detected in 37.3 percent (31/83) of the samples. The most frequent clinical diagnosis was bronchiolitis, followed by other LRTI and then pneumonia. The frequency of severe disease in children infected with more than one virus was not significantly different from the frequency of severe disease in children infected with HRV alone. Children infected with both HRV and parainfluenza virus (1.5 m.o.) were significantly younger than those infected by HRV alone (5.0 m.o.) (p = 0.0454). Overall, these results suggest that infection with a second virus does not lead to a higher frequency of severe syndromes in children presenting with LRTI.


Asunto(s)
Niño , Humanos , Nasofaringe , ARN Viral , Infecciones del Sistema Respiratorio , Rhinovirus , Adenoviridae , Adenoviridae , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Virus ARN , Virus ARN , Rhinovirus , Estaciones del Año , Índice de Severidad de la Enfermedad
5.
Mem Inst Oswaldo Cruz ; 105(5): 712-6, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20835622

RESUMEN

Human adenoviruses (HAdV) are a major cause of acute respiratory diseases (ARD), gastroenteritis, conjunctivitis and urinary infections. Between November 2000-April 2007, a total of 468 nasopharyngeal aspirate samples were collected from children with ARD at the Clinics Hospital of Uberlândia. These samples were tested by immunofluorescence assay (IFA) and 3% (14/468) tested positive for the presence of HAdV. By performing polymerase chain reaction (PCR) to detect HAdV DNA in samples that tested negative or inconclusive for all viruses identifiable by IFA (respiratory syncytial virus, parainfluenza viruses 1, 2 and 3, influenza viruses A and B and HAdV), as well as negative for rhinoviruses by reverse transcription-PCR, additional 19 cases were detected, for a total of 33 (7.1%) HAdV-positive samples. Nucleotide sequences of 13 HAdV samples were analyzed, revealing that they belonged to species B, C and E. Further analyses showed that species C (HAdV-2) was the most prevalent among the sequenced samples. To our knowledge, this is the first report describing the presence of HAdV-4 in Brazil. We also detected an isolate that was 100% identical to a part of the feline adenovirus hexon gene sequence.


Asunto(s)
Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/genética , ADN Viral/genética , Nasofaringe/virología , Infecciones del Sistema Respiratorio/virología , Adenovirus Humanos/aislamiento & purificación , Animales , Secuencia de Bases , Brasil , Gatos , Preescolar , Humanos , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Infecciones del Sistema Respiratorio/diagnóstico , Estaciones del Año
6.
Mem. Inst. Oswaldo Cruz ; 105(5): 712-716, Aug. 2010. ilus
Artículo en Inglés | LILACS | ID: lil-557235

RESUMEN

Human adenoviruses (HAdV) are a major cause of acute respiratory diseases (ARD), gastroenteritis, conjunctivitis and urinary infections. Between November 2000-April 2007, a total of 468 nasopharyngeal aspirate samples were collected from children with ARD at the Clinics Hospital of Uberlândia. These samples were tested by immunofluorescence assay (IFA) and 3 percent (14/468) tested positive for the presence of HAdV. By performing polymerase chain reaction (PCR) to detect HAdV DNA in samples that tested negative or inconclusive for all viruses identifiable by IFA (respiratory syncytial virus, parainfluenza viruses 1, 2 and 3, influenza viruses A and B and HAdV), as well as negative for rhinoviruses by reverse transcription-PCR, additional 19 cases were detected, for a total of 33 (7.1 percent) HAdV-positive samples. Nucleotide sequences of 13 HAdV samples were analyzed, revealing that they belonged to species B, C and E. Further analyses showed that species C (HAdV-2) was the most prevalent among the sequenced samples. To our knowledge, this is the first report describing the presence of HAdV-4 in Brazil. We also detected an isolate that was 100 percent identical to a part of the feline adenovirus hexon gene sequence.


Asunto(s)
Animales , Gatos , Preescolar , Humanos , Infecciones por Adenovirus Humanos , Adenovirus Humanos , ADN Viral , Nasofaringe , Infecciones del Sistema Respiratorio , Adenovirus Humanos , Secuencia de Bases , Brasil , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Infecciones del Sistema Respiratorio , Estaciones del Año
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