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1.
J Clin Microbiol ; : e0052424, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934589

RESUMO

This study compared the performance of two commercial molecular assays, the STANDARD M10 Clostridioides difficile assay (M10) and the Xpert C. difficile assay (Xpert), for detecting toxigenic C. difficile in stool specimens. A total of 487 consecutive stool specimens submitted for routine C. difficile testing between June and November 2023 were included. Following routine testing using C. DIFF QUIK CHEK COMPLETE (QCC), M10 and Xpert were tested in parallel, alongside toxigenic culture (reference standard). Additionally, two-step algorithms, using QCC on the first step and either M10 or Xpert on the second step, were assessed. Both M10 and Xpert demonstrated a sensitivity and negative predictive value (NPV) of 100%. M10 exhibited significantly higher specificity and positive predictive value (PPV; 91.9% and 64.2%, respectively) than Xpert (90.3% and 59.8%, respectively). Both two-step algorithms showed a sensitivity and NPV of 98.4% and 99.8%, respectively. The specificity and PPV of the two-step algorithm using M10 (95.2% and 75.0%, respectively) were slightly higher than those of the one using Xpert (94.8% and 73.2%, respectively), without statistical significance. Receiver operating characteristic curve analysis, assessing the predictive ability of cycle threshold (Ct) values for the detection of free toxin, exhibited an area under the curve of 0.825 for M10 and 0.843 for Xpert. This indicates the utility of Ct values as predictors for the detection of free toxin in both assays. In conclusion, M10 proves to be an effective diagnostic tool with performance comparable to Xpert, whether utilized independently or as part of a two-step algorithm.

2.
J Clin Lab Anal ; 38(9): e25043, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38804639

RESUMO

BACKGROUND: Rapid antimicrobial susceptibility testing (AST) for bloodstream infections (BSIs) facilitates the optimization of antimicrobial therapy, preventing antimicrobial resistance and improving patient outcomes. QMAC-dRAST (QuantaMatrix Inc., Korea) is a rapid AST platform based on microfluidic chip technology that performs AST directly using positive blood culture broth (PBCB). This study evaluated the performance of QMAC-dRAST for Gram-negative bacteria using PBCB and subcultured colony isolates, comparing it with that of VITEK 2 (bioMérieux, France) using broth microdilution (BMD) as the reference method. METHODS: We included 141 Gram-negative blood culture isolates from patients with BSI and 12 carbapenemase-producing clinical isolates of Enterobacterales spiked into blood culture bottles. QMAC-dRAST performance was evaluated using PBCB and colony isolates, whereas VITEK 2 and BMD were tested only on colony isolates. RESULTS: For PBCB, QMAC-dRAST achieved 92.1% categorical agreement (CA), 95.3% essential agreement (EA), with 1.8% very major errors (VMEs), 3.5% major errors (MEs), and 5.2% minor errors (mEs). With colony isolates, it exhibited 92.5% CA and 95.1% EA, with 2.0% VMEs, 3.2% MEs, and 4.8% mEs. VITEK 2 showed 94.1% CA and 96.0% EA, with 4.3% VMEs, 0.4% MEs, and 4.3% mEs. QMAC-dRAST yielded elevated error rates for specific antimicrobial agents, with high VMEs for carbapenems and aminoglycosides. The median time to result for QMAC-dRAST was 5.9 h for PBCB samples and 6.1 h for subcultured colony isolates. CONCLUSIONS: The QMAC-dRAST system demonstrated considerable strengths and comparable performance to the VITEK 2 system; however, challenges were discerned with specific antimicrobial agents, underlining a necessity for improvement.


Assuntos
Antibacterianos , Hemocultura , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana , Testes de Sensibilidade Microbiana/métodos , Humanos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Hemocultura/métodos , Antibacterianos/farmacologia
3.
Clin Infect Dis ; 77(3): 414-418, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37017075

RESUMO

In this international, multicenter open-label study (ACTG A5379) of HepB-CpG vaccine in people with human immunodeficiency virus (HIV) without prior hepatitis B virus (HBV) vaccination, all 68 participants achieved HBV seroprotective titers after the 3-dose series in the primary analysis. No unexpected safety issues were observed.


Assuntos
Vírus da Hepatite B , Hepatite B , Humanos , HIV , Receptor Toll-Like 9/agonistas , Hepatite B/prevenção & controle , Vacinas contra Hepatite B/efeitos adversos , Adjuvantes Imunológicos/efeitos adversos , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B
4.
Appl Microbiol Biotechnol ; 107(22): 6789-6798, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37725139

RESUMO

Congenital cytomegalovirus (CMV) infection is a common cause of sensorineural hearing loss and neurodevelopmental impairment in newborns. However, congenital CMV infection cannot be diagnosed using samples collected more than 3 weeks after birth because testing after this time cannot distinguish between congenital infection and postnatal infection. Herein, we developed a robust loop-mediated isothermal amplification (LAMP) assay for the large-scale screening of newborns for congenital CMV infection. In contrast to conventional quantitative polymerase chain reaction (qPCR), which detects CMV within a dynamic range of 1.0 × 106 to 1.0 × 102 copies/µL, our quantitative LAMP assay (qLAMP) detects CMV within a dynamic range of 1.1 × 108 to 1.1 × 103 copies/µL. Moreover, the turnaround time for obtaining results following DNA extraction is 90 min in qPCR but only 15 min in qLamp. The colorimetric LAMP assay can also detect CMV down to 1.1 × 103 copies/µL within 30 min, irrespective of the type of heat source. Our LAMP assay can be utilized in central laboratories as an alternative to conventional qPCR for quantitative CMV detection, or for point-of-care testing in low-resource environments, such as developing countries, via colorimetric naked-eye detection. KEY POINTS: • LAMP assay enables large-scale screening of newborns for congenital CMV infection. • LAMP allows colorimetric or quantitative detection of congenital CMV infection. • LAMP assay can be used as a point-of-care testing tool in low-resource environments.

5.
Int J Mol Sci ; 24(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37894838

RESUMO

Ovarian aging is a major obstacle in assisted reproductive medicine because it leads to ovarian dysfunction in women of advanced age. Currently, there are no effective treatments to cure age-related ovarian dysfunction. In this study, we investigated the effect of MIT-001 on the function of aged ovaries. Young and old mice were utilized in this study. MIT-001 was intraperitoneally administered, and the number of follicles and oocytes was analyzed. Each group was then retrieved for RNA and protein isolation. Total RNA was subjected to mRNA next-generation sequencing. Protein extracts from ovarian lysates were used to evaluate various cytokine levels in the ovaries. MIT-001 enhanced follicles and the number of oocytes were compared with non-treated old mice. MIT-001 downregulated immune response-related transcripts and cytokines in the ovaries of old mice. MIT-001 modulates the immune complex responsible for generating inflammatory signals and has the potential to restore the function of old ovaries and improve female fertility.


Assuntos
Oócitos , Doenças Ovarianas , Feminino , Camundongos , Animais , Humanos , Idoso , Envelhecimento , Citocinas/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , RNA/farmacologia
6.
Clin Trials ; 19(3): 285-291, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35257600

RESUMO

BACKGROUND: International Council for Harmonisation (ICH) E9 Statistical Principles for Clinical Trials was developed as a consensus guidance document to encourage worldwide harmonization of the principles of statistical methodology in clinical trials. Addendum E9 (R1) clarified and extended ICH E9 with a focus on estimands and sensitivity analyses. Since the release of E9 (R1), clinical trial protocols have included estimands, but there is variation in how they are presented. Statistical analysis plans (SAPs) are increasingly becoming publicly available (e.g. posting on ClinicalTrials.gov) and present an opportunity to link estimands with planned analyses to present the alignment of trial objectives, design, conduct, and analysis. METHODS: A table format was used to create a template for inclusion in SAPs that satisfies ICH E9 (R1) guidance to align statistical analysis to the estimand. The template provides a consistent structure for presentation of estimands and the associated analysis, and is applicable to a wide range of trial designs. We illustrate use of the template with a hypothetical clinical trial in HIV-1. RESULTS: The estimand-to-analysis table template starts with the study objective describing the clinical question of interest as written in the trial protocol. The remainder of the table describes each attribute of the estimand (treatment, target population, variable, intercurrent events, and population-level summary) in the left column (ESTIMAND), while the right column describes how each attribute will be handled using the data collected in the clinical trial (ANALYSIS). The template was applied to a hypothetical, early-phase single-arm trial, modeled after a pediatric trial in HIV, where the objective was to determine the safety of a new antiretroviral drug as part of a combination antiretroviral treatment regimen in the pediatric population. Three intercurrent events were illustrated in the table: death, premature treatment discontinuation before 24 weeks, and pregnancy. An estimand-to-analysis table from a grant application that addresses the primary objective of a placebo-controlled randomized trial is also presented to demonstrate an alternative usage. CONCLUSION: We found the template to be useful in study design, providing a snapshot of the objective, target population, potential intercurrent events, analysis plan, and considerations for missing data in one place and facilitating discussion among stakeholders. The proposed standardized presentation of estimand attributes and analysis considerations in SAPs will provide guidance to SAP authors and consistency across studies to facilitate reviews.


Assuntos
Modelos Estatísticos , Projetos de Pesquisa , Criança , Consenso , Interpretação Estatística de Dados , Humanos
7.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430821

RESUMO

In mice, zygotic genome activation (ZGA) occurs in two steps: minor ZGA at the one-cell stage and major ZGA at the two-cell stage. Regarding the regulation of gene transcription, minor ZGA is known to have unique features, including a transcriptionally permissive state of chromatin and insufficient splicing processes. The molecular characteristics may originate from extremely open chromatin states in the one-cell stage zygotes, yet the precise underlying mechanism has not been well studied. Recently, the R-loop, a triple-stranded nucleic acid structure of the DNA/RNA hybrid, has been implicated in gene transcription and DNA replication. Therefore, in the present study, we examined the changes in R-loop dynamics during mouse zygotic development, and its roles in zygotic transcription or DNA replication. Our analysis revealed that R-loops persist in the genome of metaphase II oocytes and preimplantation embryos from the zygote to the blastocyst stage. In particular, zygotic R-loop levels dynamically change as development proceeds, showing that R-loop levels decrease as pronucleus maturation occurs. Mechanistically, R-loop dynamics are likely linked to ZGA, as inhibition of either DNA replication or transcription at the time of minor ZGA decreases R-loop levels in the pronuclei of zygotes. However, the induction of DNA damage by treatment with anticancer agents, including cisplatin or doxorubicin, does not elicit genome-wide changes in zygotic R-loop levels. Therefore, our study suggests that R-loop formation is mechanistically associated with the regulation of mouse ZGA, especially minor ZGA, by modulating gene transcription and DNA replication.


Assuntos
Estruturas R-Loop , Zigoto , Camundongos , Animais , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Cromatina/genética
8.
Anal Chem ; 93(8): 3677-3685, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33606501

RESUMO

We construct a multiplex surface-enhanced Raman scattering (SERS) platform based on a plasmonic paper substrate and a double-labeled probe for the detection of multiple fluorescent dyes at high sensitivity in a single-wavelength light source system. Plasmonic paper, made of silver nanodots on three-dimensional cellulose fibers, enables highly sensitive SERS biosensing based on localized surface plasmon resonance (LSPR). The proposed method enables the identification and quantification of a range of fluorescent dyes ranging from picomolar to millimolar concentrations. The use of 5' fluorescent dyes and 3' biotin-modified probes as SERS-coded probes renders possible the separation of fluorescent dyes with streptavidin-coated magnetic beads (SMBs) and the sensitive detection of multiple dyes after the reverse transcription polymerase chain reaction (RT-PCR). This experimental study reveals the multiplex detection capability of PCR-based SERS under existing PCR conditions without modifying primer and probe sequences. The combination of magnetic bead-based separation and paper SERS platform is efficient, economical, and can be used for the simultaneous detection of two or more pathogens.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Reação em Cadeia da Polimerase , Prata , Estreptavidina , Ressonância de Plasmônio de Superfície
9.
Nano Lett ; 20(11): 7973-7979, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33104350

RESUMO

The proximity of two different materials leads to an intricate coupling of quasiparticles so that an unprecedented electronic state is often realized at the interface. Here, we demonstrate a resonance-type many-body ground state in graphene, a nonmagnetic two-dimensional Dirac semimetal, when grown on SmB6, a Kondo insulator, via thermal decomposition of fullerene molecules. This ground state is typically observed in three-dimensional magnetic materials with correlated electrons. Above the characteristic Kondo temperature of the substrate, the electron band structure of pristine graphene remains almost intact. As temperature decreases, however, the Dirac Fermions of graphene become hybridized with the Sm 4f states. Remarkable enhancement of the hybridization and Kondo resonance is observed with further cooling and increasing charge-carrier density of graphene, evidencing the Kondo screening of the Sm 4f local magnetic moment by the conduction electrons of graphene at the interface. These findings manifest the realization of the Kondo effect in graphene by the proximity of SmB6 that is tuned by the temperature and charge-carrier density of graphene.

10.
J Am Chem Soc ; 142(8): 3997-4007, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-31991083

RESUMO

Water dynamics on the protein surface mediate both protein structure and function. However, many questions remain about the role of the protein hydration layers in protein fluctuations and how the dynamics of these layers relate to specific protein properties. The fish eye lens protein γM7-crystallin (γM7) is found in vivo at extremely high concentrations nearing the packing limit, corresponding to only a few water layers between adjacent proteins. In this study, we conducted a site-specific probing of hydration water motions and side-chain dynamics at nine selected sites around the surface of γM7 using a tryptophan scan with femtosecond spectroscopy and NMR nuclear spin relaxation (NSR). We observed correlated fluctuations between hydration water and protein side chains on the time scales of a few picoseconds and hundreds of picoseconds, corresponding to local reorientations and network restructuring, respectively. These motions are heterogeneous over the protein surface and relate to the various steric and chemical properties of the local protein environment. Overall, we found that γM7 has relatively slower water dynamics within the hydration shell than a similar ß-sheet protein, which may contribute to the high packing limit of this unique protein.


Assuntos
Cristalinas/química , Proteínas/química , Água/química , Modelos Moleculares , Espectrometria de Fluorescência , Propriedades de Superfície
11.
Int J Mol Sci ; 21(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947930

RESUMO

Neuroblastoma is the most common extracranial solid tumor in childhood. The different treatments available for neuroblastoma are challenged by high rates of resistance, recurrence, and progression, most notably in advanced cases and highly malignant tumors. Therefore, the development of more targeted therapies, which are biocompatible and without undesired side effects, is highly desirable. The mechanisms of actions of platinum nanoparticles (PtNPs) and retinoic acid (RA) in neuroblastoma have remained unclear. In this study, the anticancer effects of PtNPs and RA on neuroblastoma were assessed. We demonstrated that treatment of SH-SY5Y cells with the combination of PtNPs and RA resulted in improved anticancer effects. The anticancer effects of the two compounds were mediated by cytotoxicity, oxidative stress (OS), mitochondrial dysfunction, endoplasmic reticulum stress (ERS), and apoptosis-associated networks. Cytotoxicity was confirmed by leakage of lactate dehydrogenase (LDH) and intracellular protease, and oxidative stress increased the level of reactive oxygen species (ROS), 4-hydroxynonenal (HNE), malondialdehyde (MDA), and nitric oxide (NO), and protein carbonyl content (PCC). The combination of PtNPs and RA caused mitochondrial dysfunction by decreasing the mitochondrial membrane potential (MMP), adenosine triphosphate (ATP) content, number of mitochondria, and expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). Endoplasmic reticulum-mediated stress and apoptosis were confirmed by upregulation of protein kinase RNA-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1 (IRE1), activating transcription factor 6 (ATF6), activating transcription factor 4 (ATF4), p53, Bax, and caspase-3 and down regulation of B-cell lymphoma 2 (BCl-2). PtNPs and RA induced apoptosis, and oxidative DNA damage was evident by the accumulation of 8-hydroxy-2-deoxyguanosine (8-OHdG) and 8-hydroxyguanosine (8-OHG). Finally, PtNPs and RA increased the differentiation and expression of differentiation markers. Differentiated SH-SY5Y cells pre-treated with PtNPs or RA or the combination of both were more sensitive to the cytotoxic effect of cisplatin than undifferentiated cells. To our knowledge, this is the first study to demonstrate the effect of the combination of PtNPs and RA in neuroblastoma cells. PtNPs may be a potential preconditioning or adjuvant compound in chemotherapeutic treatment. The results of this study provide a rationale for clinical evaluation of the combination of PtNPs and RA for the treatment of children suffering from high-risk neuroblastoma.


Assuntos
Antineoplásicos/farmacologia , Nanopartículas Metálicas/uso terapêutico , Neuroblastoma/tratamento farmacológico , Platina/farmacologia , Tretinoína/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/análise , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Proteínas de Neoplasias/metabolismo , Neuroblastoma/patologia , Estresse Oxidativo/efeitos dos fármacos , Peptídeo Hidrolases/análise , Platina/administração & dosagem , Platina/toxicidade , Tretinoína/administração & dosagem , beta Caroteno/farmacologia
12.
Anal Chem ; 91(19): 12275-12282, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31356055

RESUMO

A surface-enhanced Raman scattering-based lateral flow assay (SERS-LFA) technique has been developed for the rapid and accurate diagnosis of scrub typhus. Lateral flow kits for the detection of O. tsutsugamushi IgG (scrub typhus biomarker) were fabricated, and the calibration curve for various standard clinical sera concentrations were obtained by Raman measurements. The clinical sera titer values were determined by fitting the Raman data to the calibration curve. To assess the clinical feasibility of the proposed method, SERS-LFA assays were performed on 40 clinical samples. The results showed good agreement with those of the standard indirect immunofluorescence assay (IFA) method. SERS-LFA has many advantages over IFA including the less sample volume, simpler assay steps, shorter assay time, more systematic quantitative analysis, and longer assay lifetime. As SERS strips can be easily integrated with a miniaturized Raman spectrophotometer, field serodiagnosis is also more feasible.


Assuntos
Tifo por Ácaros/diagnóstico , Testes Sorológicos/instrumentação , Testes Sorológicos/métodos , Análise Espectral Raman/instrumentação , Calibragem , Células Imobilizadas , Desenho de Equipamento , Humanos , Imunoglobulina G/sangue , Orientia tsutsugamushi/genética , Orientia tsutsugamushi/imunologia , Proteínas Recombinantes/genética , Tifo por Ácaros/sangue , Tifo por Ácaros/imunologia , Análise Espectral Raman/métodos
13.
Analyst ; 144(17): 5308, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31393464

RESUMO

Correction for 'A new point-of-care test for the diagnosis of infectious diseases based on multiplex lateral flow immunoassays' by Hanbi Kim et al., Analyst, 2019, 144, 2460-2466.

14.
Analyst ; 144(8): 2460-2466, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30849145

RESUMO

Infectious diseases are transmissible or communicable illnesses and can spread quickly in some areas and become epidemics. It is critical to quickly diagnose initial infections and prevent further spread through in vitro diagnosis. However, current detection strategies have exhibited a lack of balance with regard to accuracy, time consumption, and portability until recently (e.g. serology, culturing, molecular tests, etc.). Alternatively, many studies have focused on point-of-care testing (POCT), which combines simple, rapid, and exact on-site diagnostic platforms. Moreover, multiplex detectability is necessary for emergency treatment depending on the stage of the disease or interactional infections. The lateral flow assay (LFA) is the most popular diagnostic tool that meets the required standards for colorimetric assays. Here, we review lateral flow assays based on the immune reactions for the simultaneous diagnosis of infectious diseases as the POC test. The assays employed various forms and approaches in terms of the multiplexing level system for improving the sensitivity and specificity. We briefly describe the state-of-the-art infection diagnostic methods and published performances that have been classified into three categories based on the application forms of the lateral flow immunoassay. Also, we discuss further uses of LFA and other technologies for more effective infectious disease POCT.


Assuntos
Doenças Transmissíveis/diagnóstico , Imunoensaio/métodos , Anticorpos/imunologia , Bactérias/química , Bactérias/isolamento & purificação , Proteínas de Bactérias/imunologia , Técnicas Biossensoriais/métodos , Humanos , Nanopartículas Metálicas/química , Testes Imediatos , Proteínas Virais/imunologia , Vírus/química , Vírus/isolamento & purificação
15.
Nano Lett ; 18(6): 3661-3666, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29761696

RESUMO

The interaction between a magnetic impurity, such as cerium (Ce) atom, and surrounding electrons has been one of the core problems in understanding many-body interaction in solid and its relation to magnetism. Kondo effect, the formation of a new resonant ground state with quenched magnetic moment, provides a general framework to describe many-body interaction in the presence of magnetic impurity. In this Letter, a combined study of angle-resolved photoemission (ARPES) and dynamic mean-field theory (DMFT) on Ce-intercalated graphene shows that Ce-induced localized states near Fermi energy, EF, hybridized with the graphene π-band, exhibit gradual increase in spectral weight upon decreasing temperature. The observed temperature dependence follows the expectations from the Kondo picture in the weak coupling limit. Our results provide a novel insight how Kondo physics emerges in the sea of two-dimensional Dirac electrons.

16.
Int J Mol Sci ; 20(18)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505887

RESUMO

The extensive usage of silver nanoparticles (AgNPs) as medical products such as antimicrobial and anticancer agents has raised concerns about their harmful effects on human beings. AgNPs can potentially induce oxidative stress and apoptosis in cells. However, humanin (HN) is a small secreted peptide that has cytoprotective and neuroprotective cellular effects. The aim of this study was to assess the harmful effects of AgNPs on human neuroblastoma SH-SY5Y cells and also to investigate the protective effect of HN from AgNPs-induced cell death, mitochondrial dysfunctions, DNA damage, and apoptosis. AgNPs were prepared with an average size of 18 nm diameter to study their interaction with SH-SY5Y cells. AgNPs caused a dose-dependent decrease of cell viability and proliferation, induced loss of plasma-membrane integrity, oxidative stress, loss of mitochondrial membrane potential (MMP), and loss of ATP content, amongst other effects. Pretreatment or co-treatment of HN with AgNPs protected cells from several of these AgNPs induced adverse effects. Thus, this study demonstrated for the first time that HN protected neuroblastoma cells against AgNPs-induced neurotoxicity. The mechanisms of the HN-mediated protective effect on neuroblastoma cells may provide further insights for the development of novel therapeutic agents against neurodegenerative diseases.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Nanopartículas Metálicas/toxicidade , Mitocôndrias/metabolismo , Proteínas Mitocondriais/farmacologia , Prata/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Membrana Celular/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas Metálicas/química , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Estresse Oxidativo/efeitos dos fármacos , Prata/química
17.
Int J Mol Sci ; 20(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634552

RESUMO

Graphene and its derivatives are emerging as attractive materials for biomedical applications, including antibacterial, gene delivery, contrast imaging, and anticancer therapy applications. It is of fundamental importance to study the cytotoxicity and biocompatibility of these materials as well as how they interact with the immune system. The present study was conducted to assess the immunotoxicity of graphene oxide (GO) and vanillin-functionalized GO (V-rGO) on THP-1 cells, a human acute monocytic leukemia cell line. The synthesized GO and V-rGO were characterized by using various analytical techniques. Various concentrations of GO and V-rGO showed toxic effects on THP-1 cells such as the loss of cell viability and proliferation in a dose-dependent manner. Cytotoxicity was further demonstrated as an increased level of lactate dehydrogenase (LDH), loss of mitochondrial membrane potential (MMP), decreased level of ATP content, and cell death. Increased levels of reactive oxygen species (ROS) and lipid peroxidation caused redox imbalance in THP-1 cells, leading to increased levels of malondialdehyde (MDA) and decreased levels of anti-oxidants such as glutathione (GSH), glutathione peroxidase (GPX), super oxide dismutase (SOD), and catalase (CAT). Increased generation of ROS and reduced MMP with simultaneous increases in the expression of pro-apoptotic genes and downregulation of anti-apoptotic genes suggest that the mitochondria-mediated pathway is involved in GO and V-rGO-induced apoptosis. Apoptosis was induced consistently with the significant DNA damage caused by increased levels of 8-oxo-dG and upregulation of various key DNA-regulating genes in THP-1 cells, indicating that GO and V-rGO induce cell death through oxidative stress. As a result of these events, GO and V-rGO stimulated the secretion of various cytokines and chemokines, indicating that the graphene materials induced potent inflammatory responses to THP-1 cells. The harshness of V-rGO in all assays tested occurred because of better charge transfer, various carbon to oxygen ratios, and chemical compositions in the rGO. Overall, these findings suggest that it is essential to better understand the parameters governing GO and functionalized GO in immunotoxicity and inflammation. Rational design of safe GO-based formulations for various applications, including nanomedicine, may result in the development of risk management methods for people exposed to graphene and graphene family materials, as these nanoparticles can be used as delivery agents in various biomedical applications.


Assuntos
Benzaldeídos , Grafite , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Nanopartículas , Óxidos , Apoptose/efeitos dos fármacos , Benzaldeídos/química , Biomarcadores , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Dano ao DNA/efeitos dos fármacos , Grafite/química , Humanos , Leucemia Monocítica Aguda , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanopartículas/química , Nanopartículas/ultraestrutura , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Óxidos/química , Espécies Reativas de Oxigênio/metabolismo
18.
Clin Infect Dis ; 67(2): 251-260, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29365083

RESUMO

Background: Mild-to-moderate AIDS-associated Kaposi sarcoma (KS) often responds to antiretroviral therapy (ART) alone; the role of chemotherapy is unclear. We assessed the impact of immediate vs as-needed oral etoposide (ET) among human immunodeficiency virus (HIV)-infected individuals with mild-to-moderate KS initiating ART. Methods: Chemotherapy-naive, HIV type 1-infected adults with mild-to-moderate KS initiating ART in Africa and South America were randomized to ART (tenofovir/emtricitabine/efavirenz) alone (chemotherapy "as-needed" arm) vs ART plus up to 8 cycles of oral ET (immediate arm). Participants with KS progression on ART alone received ET as part of the as-needed strategy. Primary outcome was ordinal as follows: failure, stable, and response at 48 weeks. Secondary outcomes included time to initial KS progression, KS-associated immune reconstitution inflammatory syndrome (KS-IRIS), and KS response. Results: Of 190 randomized participants (as-needed = 94, immediate = 96), the majority were men (71%) and African (93%). Failure (53.8% vs 56.6%), stable (16.3% vs 10.8%), and response (30% vs 32.5%) did not differ between arms (as-needed vs immediate) among those with week 48 data potential (N = 163, P = .91). Time to KS progression (P = .021), KS-IRIS (P = .003), and KS response (P = .003) favored the immediate arm. Twenty-five participants died (13%). Mortality, adverse events, CD4+ T-cell changes, and HIV RNA suppression were similar at 48 weeks. Conclusions: Among HIV-infected adults with mild-to-moderate KS, immediate ET provided early, nondurable clinical benefits. By 48 weeks, no clinical benefit was observed compared to use of ET as needed. Mortality was high and tumor response was low. Clinical Trials Registration: NCT01352117.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antineoplásicos Fitogênicos/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Etoposídeo/uso terapêutico , Sarcoma de Kaposi/tratamento farmacológico , Administração Oral , Adulto , África Subsaariana , Biópsia , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Recursos em Saúde , Humanos , Síndrome Inflamatória da Reconstituição Imune , Masculino , Pele/patologia , América do Sul
19.
Liver Int ; 38(6): 1010-1021, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29091342

RESUMO

BACKGROUND & AIMS: We report data from two similarly designed studies that evaluated the efficacy, safety, and optimal duration of ledipasvir/sofosbuvir (LDV/SOF) ± ribavirin (RBV) for retreatment of chronic hepatitis C virus (HCV) in individuals who failed to achieve sustained virological response (SVR) with prior SOF-based, non-NS5A inhibitor-containing regimens. METHODS: The RESCUE study enrolled HCV mono-infected adults with genotype (GT) 1 or 4. Non-cirrhotic participants were randomized to 12 weeks of LDV/SOF or LDV/SOF + RBV. Compensated cirrhotic participants were randomized to LDV/SOF + RBV (12 weeks) or LDV/SOF (24 weeks). The AIDS Clinical Trials Group A5348 study randomized genotype 1 adults with HCV/HIV co-infection to LDV/SOF + RBV (12 weeks) or LDV/SOF (24 weeks). Both studies used SVR at 12 weeks post-treatment (SVR12) as the primary endpoint. RESULTS: In the RESCUE study, 82 participants were randomized and treated, and all completed treatment. Overall, SVR12 was 88% (72/82); 81-100% in non-cirrhotic participants treated with LDV/SOF or LDV/SOF + RBV for 12 weeks and 80-92% in cirrhotic participants treated with LDV/SOF + RBV for 12 weeks or LDV/SOF for 24 weeks. Adverse events (AEs), mostly mild-to-moderate in severity, were experienced by 78% of participants, with headache and fatigue most frequently reported. One serious AE, not related to treatment, was observed. No premature discontinuations of study drug, or deaths occurred. In the A5348 study, seven participants were randomized (cirrhotic n = 1; GT1a n = 5) and all attained SVR12, with no serious AEs or premature discontinuations. CONCLUSIONS: In this SOF-experienced, NS5A inhibitor-naïve population, which included participants with cirrhosis or HCV/HIV co-infection, high SVR12 rates were achieved.


Assuntos
Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Coinfecção/tratamento farmacológico , Fluorenos/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Ribavirina/administração & dosagem , Uridina Monofosfato/análogos & derivados , Adulto , Idoso , Antivirais/efeitos adversos , Benzimidazóis/efeitos adversos , Coinfecção/virologia , Fadiga/etiologia , Feminino , Fluorenos/efeitos adversos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Cefaleia/etiologia , Hepacivirus/genética , Humanos , Cirrose Hepática , Masculino , Pessoa de Meia-Idade , Gravidez , Ribavirina/efeitos adversos , Sofosbuvir , Resposta Viral Sustentada , Uridina Monofosfato/administração & dosagem , Uridina Monofosfato/efeitos adversos
20.
Dig Dis Sci ; 63(11): 2969-2974, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30218427

RESUMO

BACKGROUND AND AIMS: The patatin-like phospholipase domain-containing 3 (PNPLA3) gene has been associated with the development of alcoholic and nonalcoholic steatohepatitis. Using a newly developed and validated assay for PNPLA3, we explored the prevalence of gene polymorphisms in a cohort of HCV/HIV-coinfected individuals to determine whether there was an association with insulin resistance or hepatic fibrosis. METHODS: A high-resolution melting point (HRM) assay was developed and validated. The assay was used to evaluate samples obtained in the context of a clinical trial performed at ACTG sites across the USA in HIV-infected patients. Clinical features and treatment outcomes were assessed in relation to the PNPLA3 genotype. RESULTS: The HRM methodology demonstrated 100% concordance with results obtained by Sanger sequencing. Among 241 participants tested, 66.0% had the wild-type allele (CC) and the remainder had the aberrant PNPLA3 gene polymorphism in the homozygotic (GG) or heterozygotic (CG) form. Race and ethnicity were associated with PNPLA3 genotype but fibrosis stage, Homeostatic Model Assessment of Insulin Resistance, and HCV treatment outcome were not. CONCLUSION: The HRM method is an effective, rapid technique for characterizing PNPLA3 genotype. In those with HCV/HIV infection, nearly 40% carry gene polymorphisms associated with the development of NASH or ASH. Prospective studies should focus on this group to determine whether they represent a subset of HIV-infected persons at increased risk of fibrotic progression.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/genética , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/genética , Lipase/genética , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Estudos de Coortes , Feminino , Infecções por HIV/diagnóstico , Hepatite C Crônica/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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