Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
2.
Environ Technol ; : 1-9, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100572

RESUMO

In this study, a one-step solvothermal method was used to fabricate Fe3+ doped BiOCl microflowers with abundant oxygen vacancies (OVs) in the presence of glacial acetic acid. Various analytical techniques were employed to characterize the structural, morphological, and optical properties of the prepared samples. The presence of OVs was confirmed by low temperature electron paramagnetic resonance (EPR) analysis. The photocatalytic results show that Fe3+ doped BiOCl photocatalysts have higher activity than the bare BiOCl, and 10% Fe3+/BiOCl exhibits the highest photocatalytic performance, the photocatalytic efficiency of this sample is 2.3 and 1.1 times higher than that of the blank BiOCl toward photocatalytic degradation of perfluorooctanoic acid (PFOA) and rhodamine B (RhB), respectively. Furthermore, Fe3+ doped BiOCl demonstrates excellent reusability. Based on the experimental observations, an enhancement mechanism for the photocatalytic activity of Fe3+ doped BiOCl was reasonably elucidated.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37658836

RESUMO

HIV-1CRF08_BC is the most prevalent epidemic subtype among heterosexual (HET) and intravenous drug users (IDUs) in Kunming, Yunnan. Using the pol region of gene sequences derived from molecular epidemiological surveys, we developed a molecular transmission network for the purpose of analyzing its epidemiological characteristics, assessing its epidemiological trends, identifying its potential transmission relationships, and developing targeted interventions. HyPhy 2.2.4 was used to calculate pairwise genetic distances between sequences; GraphPad-Prism 8.0 was employed to determine the standard genetic distance; and Cytoscope 3.7.2 was applied to visualize the network. We used the network analysis tools to investigate network characteristics and the Molecular Complex Detection (MCODE) tool to observe the growth of the network. We utilized a logistic regression model to examine the factors influencing clustering and a zero-inflated Poisson model to investigate the factors influencing potential transmission links. At the standard genetic distance threshold of 0.008, 406 out of 858 study participants were clustered in 132 dissemination networks with a total network linkage of 868, and the number of links per sequence ranged from 1 to 19. The MCODE analysis identified three significant modular clusters in the networks, with network scores ranging from 4.9 to 7. In models of logistic regression, HET, middle-aged and elderly individuals, and residents of northern and southeastern Kunming were more likely to enter the transmission network. According to the zero-inflated Poisson model, age, transmission category, sampling year, marital status, and CD4+ T level had a significant effect on the size of links. The molecular clusters in Kunming's molecular transmission network are specific and aggregate to a certain extent. HIV-1 molecular network analysis provided information on local transmission characteristics, and these findings helped to determine the priority of transmission-reduction interventions.

4.
J Med Virol ; 95(2): e28516, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36680413

RESUMO

In China, most SARS-CoV-2-infected individuals had been vaccinated with inactivated vaccines. However, little is known about their immune resistances to the previous variants of concerns (VOCs) and the current Omicron sublineages. Here, we collected convalescent serum samples from SARS-CoV-2-infected individuals during the ancestral, Delta, and Omicron BA.1 waves, and evaluated their cross-neutralizing antibodies (nAbs) against the previous VOCs and the current Omicron sublineages using VSV-based pseudoviruses. In the convalescents who had been unvaccinated and vaccinated with two doses of inactivated vaccines, we found infections from either the ancestral or the Delta strain elicited moderate cross-nAbs to previous VOCs, but very few cross-nAbs to the Omicron sublineages, including BA.1, BA.2, BA.3, and BA.4/5. The individuals who had been vaccinated with two doses of inactivated vaccines before Omicron BA.1 infection had moderate nAbs to Omicron BA.1, but weak cross-nAbs to the other Omicron sublineages. While three doses of inactivated vaccines followed Omicron BA.1 infection induced elevated and still weak cross-nAbs to other Omicron sublineages. Our results indicate that the Omicron sublineages show significant immune escape in the previously SARS-CoV-2-infected individuals and thus highlights the importance of vaccine boosters in this population.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Vacinas de Produtos Inativados , Soroterapia para COVID-19 , Anticorpos Neutralizantes , Anticorpos Antivirais
5.
Cell Res ; 32(12): 1068-1085, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36357786

RESUMO

The emerging SARS-CoV-2 variants, commonly with many mutations in S1 subunit of spike (S) protein are weakening the efficacy of the current vaccines and antibody therapeutics. This calls for the variant-proof SARS-CoV-2 vaccines targeting the more conserved regions in S protein. Here, we designed a recombinant subunit vaccine, HR121, targeting the conserved HR1 domain in S2 subunit of S protein. HR121 consisting of HR1-linker1-HR2-linker2-HR1, is conformationally and functionally analogous to the HR1 domain present in the fusion intermediate conformation of S2 subunit. Immunization with HR121 in rabbits and rhesus macaques elicited highly potent cross-neutralizing antibodies against SARS-CoV-2 and its variants, particularly Omicron sublineages. Vaccination with HR121 achieved near-full protections against prototype SARS-CoV-2 infection in hACE2 transgenic mice, Syrian golden hamsters and rhesus macaques, and effective protection against Omicron BA.2 infection in Syrian golden hamsters. This study demonstrates that HR121 is a promising candidate of variant-proof SARS-CoV-2 vaccine with a novel conserved target in the S2 subunit for application against current and future SARS-CoV-2 variants.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Cricetinae , Camundongos , Humanos , Coelhos , SARS-CoV-2 , Macaca mulatta , Mesocricetus , Glicoproteína da Espícula de Coronavírus/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Camundongos Transgênicos , Anticorpos Antivirais
6.
Virol Sin ; 37(6): 804-812, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36167254

RESUMO

The continuously arising of SARS-CoV-2 variants has been posting a great threat to public health safety globally, from B.1.17 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.617.2 (Delta) to B.1.1.529 (Omicron). The emerging or re-emerging of the SARS-CoV-2 variants of concern is calling for the constant monitoring of their epidemics, pathogenicity and immune escape. In this study, we aimed to characterize replication and pathogenicity of the Alpha and Delta variant strains isolated from patients infected in Laos. The amino acid mutations within the spike fragment of the isolates were determined via sequencing. The more efficient replication of the Alpha and Delta isolates was documented than the prototyped SARS-CoV-2 in Calu-3 and Caco-2 â€‹cells, while such features were not observed in Huh-7, Vero E6 and HPA-3 â€‹cells. We utilized both animal models of human ACE2 (hACE2) transgenic mice and hamsters to evaluate the pathogenesis of the isolates. The Alpha and Delta can replicate well in multiple organs and cause moderate to severe lung pathology in these animals. In conclusion, the spike protein of the isolated Alpha and Delta variant strains was characterized, and the replication and pathogenicity of the strains in the cells and animal models were also evaluated.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2 , Células CACO-2 , COVID-19/virologia , Camundongos Transgênicos , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus , Virulência
7.
Mil Med Res ; 9(1): 24, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35619176

RESUMO

BACKGROUND: Mucosal-associated invariant T (MAIT) cells are systemically depleted in human immunodeficiency virus type 1 (HIV-1) infected patients and are not replenished even after successful combined antiretroviral therapy (cART). This study aimed to identify the mechanism underlying MAIT cell depletion. METHODS: In the present study, we applied flow cytometry, single-cell RNA sequencing and immunohistochemical staining to evaluate the characteristics of pyroptotic MAIT cells in a total of 127 HIV-1 infected individuals, including 69 treatment-naive patients, 28 complete responders, 15 immunological non-responders, and 15 elite controllers, at the Fifth Medical Center of Chinese PLA General Hospital, Beijing, China. RESULTS: Single-cell transcriptomic profiles revealed that circulating MAIT cells from HIV-1 infected subjects were highly activated, with upregulation of pyroptosis-related genes. Further analysis revealed that increased frequencies of pyroptotic MAIT cells correlated with markers of systemic T-cell activation, microbial translocation, and intestinal damage in cART-naive patients and poor CD4+ T-cell recovery in long-term cART patients. Immunohistochemical staining revealed that MAIT cells in the gut mucosa of HIV-1 infected patients exhibited a strong active gasdermin-D (GSDMD, marker of pyroptosis) signal near the cavity side, suggesting that these MAIT cells underwent active pyroptosis in the colorectal mucosa. Increased levels of the proinflammatory cytokines interleukin-12 (IL-12) and IL-18 were observed in HIV-1 infected patients. In addition, activated MAIT cells exhibited an increased pyroptotic phenotype after being triggered by HIV-1 virions, T-cell receptor signals, IL-12 plus IL-18, and combinations of these factors, in vitro. CONCLUSIONS: Activation-induced MAIT cell pyroptosis contributes to the loss of MAIT cells in HIV-1 infected patients, which could potentiate disease progression and poor immune reconstitution.


Assuntos
Infecções por HIV , HIV-1 , Células T Invariantes Associadas à Mucosa , Infecções por HIV/tratamento farmacológico , Humanos , Interleucina-12 , Interleucina-18 , Piroptose
9.
Curr HIV Res ; 19(4): 368-376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33902415

RESUMO

BACKGROUND: Injecting drugs is associated with a high risk of HIV infection, alongside the risk of a drug overdose and mental health problems. OBJECTIVE: To evaluate the effect of methadone maintenance treatment (MMT) combined with rilpivirine (RPV)-based regimens on drug use of HIV individuals. METHODS: This study was a prospective, open-label, controlled, drug-drug interaction trial at a single center for 24 weeks. Participants on stable MMT were randomly divided into two groups administered RPV/TDF/3TC (RPV group) and EFV/TDF/3TC (EFV group), respectively. Adjustment doses of methadone were monitored for 12 weeks. HIV-1 RNA was used to evaluate the effects of antiretroviral therapy at week 24. Acute opioid withdrawal-, drug craving questionnaire- and MOSHIV scales were used to assess study outcomes. RESULTS: 22 and 18 cases of HIV-infected drug users were recruited in the RPV and EFV groups, respectively. Thirty-one cases had completed monitoring and clinical evaluation at week 24. In the RPV and EFV groups, 32% and 56% of the participants had methadone dose adjustment, respectively, indicating a significantly lower rate in the RPV group. The rates of individuals with HIV RNA levels from 50-500 copies/ml were 94% (RPV group) and 90% (EFV group). The drug craving questionnaire scale scores decreased in both groups. After one week of treatments, acute opioid withdrawal scale scores increased in both groups, with no significant difference between them. CONCLUSION: Concomitant administration of RPV does not significantly affect methadone and could decrease withdrawal symptoms. An RPV-based regimen may be used as first-line treatment in IDUs with HIV infection.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Alcinos , Fármacos Anti-HIV/uso terapêutico , Benzoxazinas , Ciclopropanos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Metadona/uso terapêutico , Estudos Prospectivos , Rilpivirina/uso terapêutico , Carga Viral
10.
J Clin Invest ; 131(6)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720048

RESUMO

Chronic HIV-1 infection is generally characterized by progressive CD4+ T cell depletion due to direct and bystander death that is closely associated with persistent HIV-1 replication and an inflammatory environment in vivo. The mechanisms underlying the loss of CD4+ T cells in patients with chronic HIV-1 infection are incompletely understood. In this study, we simultaneously monitored caspase-1 and caspase-3 activation in circulating CD4+ T cells, which revealed that pyroptotic and apoptotic CD4+ T cells are distinct cell populations with different phenotypic characteristics. Levels of pyroptosis and apoptosis in CD4+ T cells were significantly elevated during chronic HIV-1 infection, and decreased following effective antiretroviral therapy. Notably, the occurrence of pyroptosis was further confirmed by elevated gasdermin D activation in lymph nodes of HIV-1-infected individuals. Mechanistically, caspase-1 activation closely correlated with the inflammatory marker expression and was shown to occur through NLRP3 inflammasome activation driven by virus-dependent and/or -independent ROS production, while caspase-3 activation in CD4+ T cells was more closely related to T cell activation status. Hence, our findings show that NLRP3-dependent pyroptosis plays an essential role in CD4+ T cell loss in HIV-1-infected patients and implicate pyroptosis signaling as a target for anti-HIV-1 treatment.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/imunologia , HIV-1 , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Adolescente , Adulto , Apoptose/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Estudos de Casos e Controles , Caspase 1/metabolismo , Caspase 3/metabolismo , Feminino , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Humanos , Inflamassomos/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Modelos Imunológicos , Piroptose/imunologia , Espécies Reativas de Oxigênio/metabolismo , Carga Viral , Adulto Jovem
11.
Zool Res ; 42(2): 161-169, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33554485

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19) continue to impact countries worldwide. At present, inadequate diagnosis and unreliable evaluation systems hinder the implementation and development of effective prevention and treatment strategies. Here, we conducted a horizontal and longitudinal study comparing the detection rates of SARS-CoV-2 nucleic acid in different types of samples collected from COVID-19 patients and SARS-CoV-2-infected monkeys. We also detected anti-SARS-CoV-2 antibodies in the above clinical and animal model samples to identify a reliable approach for the accurate diagnosis of SARS-CoV-2 infection. Results showed that, regardless of clinical symptoms, the highest detection levels of viral nucleic acid were found in sputum and tracheal brush samples, resulting in a high and stable diagnosis rate. Anti-SARS-CoV-2 immunoglobulin M (IgM) and G (IgG) antibodies were not detected in 6.90% of COVID-19 patients. Furthermore, integration of nucleic acid detection results from the various sample types did not improve the diagnosis rate. Moreover, dynamic changes in SARS-CoV-2 viral load were more obvious in sputum and tracheal brushes than in nasal and throat swabs. Thus, SARS-CoV-2 nucleic acid detection in sputum and tracheal brushes was the least affected by infection route, disease progression, and individual differences. Therefore, SARS-CoV-2 nucleic acid detection using lower respiratory tract samples alone is reliable for COVID-19 diagnosis and study.


Assuntos
Teste para COVID-19/veterinária , COVID-19/diagnóstico , SARS-CoV-2/genética , Animais , Anticorpos Antivirais , Modelos Animais de Doenças , Haplorrinos , Humanos , Estudos Longitudinais , Faringe/virologia , Valor Preditivo dos Testes , SARS-CoV-2/imunologia , Manejo de Espécimes , Escarro/virologia
12.
Signal Transduct Target Ther ; 5(1): 294, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33361761

RESUMO

Understanding the processes of immune regulation in patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial for improving treatment. Here, we performed longitudinal whole-transcriptome RNA sequencing on peripheral blood mononuclear cell (PBMC) samples from 18 patients with coronavirus disease 2019 (COVID-19) during their treatment, convalescence, and rehabilitation. After analyzing the regulatory networks of differentially expressed messenger RNAs (mRNAs), microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) between the different clinical stages, we found that humoral immunity and type I interferon response were significantly downregulated, while robust T-cell activation and differentiation at the whole transcriptome level constituted the main events that occurred during recovery from COVID-19. The formation of this T cell immune response might be driven by the activation of activating protein-1 (AP-1) related signaling pathway and was weakly affected by other clinical features. These findings uncovered the dynamic pattern of immune responses and indicated the key role of T cell immunity in the creation of immune protection against this disease.


Assuntos
COVID-19/genética , Imunidade Humoral/genética , Linfócitos T/metabolismo , Transcriptoma/genética , COVID-19/epidemiologia , COVID-19/patologia , Feminino , Humanos , Imunidade Humoral/imunologia , Leucócitos Mononucleares/metabolismo , Masculino , MicroRNAs , RNA Longo não Codificante/genética , RNA-Seq , SARS-CoV-2/genética , SARS-CoV-2/patogenicidade , Linfócitos T/imunologia , Linfócitos T/patologia , Fator de Transcrição AP-1/genética
15.
Expert Rev Clin Pharmacol ; 12(6): 565-571, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31091116

RESUMO

Background: The combination of rilpivirine with methadone may result in complex interactions secondary to the induction of oxidative metabolism by rilpivirine. Research design and methods: TMC278IFD4007 was a single-center, prospective, open-label, multiple-dose study with 12 HIV-infected Chinese participants. The objective was to evaluate the potential effect of rilpivirine on the pharmacokinetics of methadone. The participants received a daily dose of 25 mg rilpivirine for 11 days with individualized methadone ranging from 25 to 100 mg. Pharmacokinetic studies of methadone were conducted on day 1 and 11. Opiate withdrawal symptoms were evaluated. Results: A large inter-subject variability was noted in methadone pharmacokinetics. Rilpivirine increased methadone minimum and maximum plasma concentrations (Cmin; Cmax) and area under the plasma concentration-time curve versus methadone alone (least-square mean ratio; 90% confidence interval) by 5% (1.05; 0.46, 2.39), 5% (1.05; 0.73, 1.52), and 6% (0.75; 0.74, 1.50) as measured in S-methadone, and 5% (1.05; 0.50, 2.22), 5% (1.05; 0.74, 1.50), and 5% (1.05; 0.76, 1.46) as measured in R-methadone, respectively. No opioid withdrawal symptoms or methadone dose adjustments were reported. Co-administration was well tolerated without serious adverse effects or discontinuations. Conclusion: Concomitant administration of rilpivirine was unlikely to have significant effects on the pharmacokinetics of methadone.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Metadona/farmacocinética , Rilpivirina/administração & dosagem , Adulto , Fármacos Anti-HIV/farmacologia , Área Sob a Curva , Povo Asiático , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Humanos , Masculino , Metadona/administração & dosagem , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Estudos Prospectivos , Rilpivirina/farmacologia
16.
Virol J ; 16(1): 5, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30621727

RESUMO

BACKGROUND: Understanding the prevalence and evolution of HIV-1 drug resistance (DR) and associated mutation patterns is critical to implementing free antiretroviral therapy in Yunnan, the first antiretroviral treatment location in China. Here We provide a basis for understanding the occurrence and development of HIV-1 resistance in Yunnan and a theoretical foundational for strategy to delay HIV-1 drug resistance and achieve successful individualized treatment. METHODS: Plasma samples from different cities/prefectures were collected at Yunnan Provincial Hospital of Infectious Disease from January 2010 to September 2016, and those from drug-resistant individuals were genotyped using in-house assays, 88 patients were selected for the study who had been on treatment for ≥6 months (and for whom drug resistance was then measured), and each patient had at least 3 genotype resistance tests and who were enrolled to analyze mutation and evolution of HIV resistance. RESULTS: 264 Pol sequences of 88 patients were obtained. Drug resistance levels to eight drugs increased to varying degrees with prolonged treatment. Resistance to efavirenz (EFV) and etravirine (ETR) showed the highest change, comparisons of resistant changes to second and first and to third and second agents showed altered level of drug resistance were 25 and 20 cases, 28 and 18 cases, respectively. The smallest change was Lopinavir/Ritonavir (LPV/r) present 2 and 3 cases; Resistance to lamivudine (3TC) and lopinavir/ritonavir (LPV/r) was high among patients detected thrice, whereas other drugs were distributed in all resistance levels. M184 V/I (26.14%), T69S (11.36%), and T215Y/I (10.23%) mutations were the most common in nucleoside reverse transcriptase inhibitors (NRTIs), and K103 N/R/S (21.59%), V179D/E (20.45%) in Non-NRTIs (NNRTIs). Furthermore, L10 V/F/I (6.82%), A71V (4.55%), and I54V (4.55%) mutations were common in protease inhibitors (PIs). CONCLUSIONS: We found dynamic genotypic changes in HIV-1 drug-resistance in Yunnan, with prolonged treatment, and drug resistance was inevitable. However, resistance to different drugs occurred at varying times, and mutation site emergence was the main cause. These findings enhance our understanding of evolution and regulation, and are valuable for developing HIV-1 DR prevention strategies in Yunnan.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral/genética , Evolução Molecular , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Falha de Tratamento , Adolescente , Adulto , Terapia Antirretroviral de Alta Atividade , Criança , China/epidemiologia , Feminino , Genótipo , Infecções por HIV/epidemiologia , HIV-1/genética , Humanos , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Adulto Jovem
17.
Methods Mol Biol ; 1776: 569-578, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29869266

RESUMO

Controlled synthesis of small and catalytically active noble metal nanoparticles under mild aqueous conditions is an unmet challenge. Genetically modified tobacco mosaic virus (TMV) can serve as a preferential precursor adsorption and growth sites for the controlled synthesis of palladium (Pd) nanoparticles with high catalytic activity. Here we describe detailed methods for the synthesis of Pd-TMV nanocomplexes as well as their integration into polymeric hydrogel microparticle platforms with controlled dimensions via a simple replica molding process. Such Pd-TMV-containing hydrogel particles may be useful in environmental remediation of toxic chemicals such as carcinogenic dichromate ions.


Assuntos
Recuperação e Remediação Ambiental , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Biologia Molecular/métodos , Vírus do Mosaico do Tabaco/química , Catálise , Complexos de Coordenação/química , Hidrogéis/química , Nanopartículas Metálicas/química , Paládio/química
18.
Phytomedicine ; 39: 93-99, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29433688

RESUMO

BACKGROUND: Clinical methicillin-resistant Staphylococcus aureus (MRSA) is a thorny problem in current anti-infective therapeutics and a challenge of new drug development. Plant prenylflavonoids possess anti-MRSA activity, but few of the prenylflavonoids have been reported the synergistic anti-MRSA effect when they are used in combination with conventional antibacterial agents. PURPOSE: This study deals with anti-MRSA activity of four prenylflavonoids from the root bark of Morus alba and their synergism with 11 conventional antibacterial agents. METHODS: Chromatographic methods and spectral analysis were used to isolate and identify the prenylflavonoids. The antibacterial activity and synergism were assessed by the broth microdilution method, checkerboard dilution test, and time-kill curve assay, respectively. RESULTS: Four prenylflavonoids, i.e., cyclocommunol (Cy, 1), morusinol (Ml, 2), morusin (Mi, 3) and kuwanon E (Ku, 4), were isolated from Morus alba bark ethanol extract. Compounds 1, 3 and 4 showed high antimicrobial activity on both methicillin-susceptible S. aureus (MSSA) and MRSA strains with MICs/MBCs at 4-16/32-64 and 4-32/16-128 µg/ml, respectively. Ml (2) was not active. Compound 2 showed synergy with amikacin (AK) and streptomycin (SM) against all the ten MRSA isolates. Ml (2) and Ku (4) also showed synergy with ciprofloxacin (CI), etimicin (EM) and vancomycin (VA) against 7-9 isolates. The fractional inhibitory concentration indices (FICIs) ranged 0.09-1.00 and the dose reduction indices (DRIs) of these antibacterial agents ranged 2-128. Cy (1) and Mi (3) showed synergy with the tested antibacterial agents against only 1-3 MRSA isolates except VA. Furthermore, the MRSA resistance could be reversed in the combinations of AK with Cy, Ml, Mi and Ku; EM with Mi and Ku; and SM with Ml by the criteria of MIC interpretive standards for Staphylococcus spp. of CLSI. All the combinations showed only indifference in the 1 × MIC time-killing experiments. The prenylated substitutions play an important role in the activity of the compounds used alone and combined with the tested antibacterials. CONCLUSIONS: The study revealed for the first time the anti-MRSA synergism of prenylflavonoids 1-4 with eleven antibacterial agents and the reversal of MRSA resistance to aminoglycosides, especially amikacin. The results might be valuable for the development of new antibacterial drugs and synergists against MRSA infection.


Assuntos
Antibacterianos/farmacologia , Flavonoides/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Morus/química , Aminoglicosídeos/farmacologia , Antibacterianos/química , Linhagem Celular , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Meticilina/farmacologia , Testes de Sensibilidade Microbiana , Casca de Planta/química , Raízes de Plantas/química , Vancomicina/farmacologia
20.
AIDS Res Hum Retroviruses ; 32(5): 467-70, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26678279

RESUMO

Recombination contributes substantially to the genetic diversity of HIV-1. Recently, many kinds of circulating recombinant forms (CRFs) and unique recombinant forms (URFs) were identified in China, especially in areas with multiple subtypes of HIV-1 circulating. Yunnan, which borders the "Golden triangle" region of South China, is an epicenter of HIV-1 infections in China. Multiple subtypes, including subtypes B, CRF01_AE, CRF07_BC, and CRF08_BC, were found epidemic in the area. Many URFs composed of subtypes B and C genomes were identified in Yunnan; however, CRF01_AE/B recombinant form is relatively rare. In this study, we identified a novel recombinant form of CRF01_AE/B, which was isolated from a heterosexual transmitted individual. The genomic structure of the strain is distinctly different from any previously reported URFs. Three CRF01_AE segments were inserted into the subtype B backbone genome. In the past few years, many kinds of URFs and CRFs have emerged and spread quickly in China, which implies that coinfection or super infection of more than one HIV-1 subtype might be common in China, especially in Yunnan. Therefore, more work is needed to monitor the appearance of URFs and survey the epidemiologic significance of the new recombination.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/genética , RNA Viral/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética , Sequência de Bases , China/epidemiologia , Variação Genética , Genoma Viral/genética , Infecções por HIV/virologia , Humanos , Masculino , Recombinação Genética , Análise de Sequência de DNA , Carga Viral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...