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Recent work has shown that an amorphous drug-polymer salt can be highly stable against crystallization under hot and humid storage conditions (e.g., 40 °C/75% RH) and provide fast release and that these advantages depend on the degree of salt formation. Here, we investigate the salt formation between the basic drug lumefantrine (LMF) and several acidic polymers: poly(acrylic acid) (PAA), hypromellose phthalate (HPMCP), hypromellose acetate succinate (HPMCAS), cellulose acetate phthalate (CAP), Eudragit L100, and Eudragit L100-55. Salt formation was performed by "slurry synthesis" where dry components were mixed at room temperature in the presence of a small quantity of an organic solvent, which was subsequently removed. This method achieved more complete salt formation than the conventional methods of hot-melt extrusion and rotary evaporation. The acidic group density of a polymer was determined by nonaqueous titration in the same solvent used for slurry synthesis; the degree of LMF protonation was determined by X-ray photoelectron spectroscopy. The polymers studied show very different abilities to protonate LMF when compared at a common drug loading, following the order PAA > (HPMCP â¼ CAP â¼ L100 â¼ L100-55) > HPMCAS, but the difference largely disappears when the degree of protonation is plotted against the concentration of the available acidic groups for reaction. This indicates that the extent of salt formation is mainly controlled by the acidic group density and is less sensitive to the polymer architecture. Our results are relevant for selecting the optimal polymer to control the degree of ionization in amorphous solid dispersions.
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Polímeros , Polímeros/química , Metilcelulose/química , Metilcelulose/análogos & derivados , Cristalização/métodos , Celulose/química , Celulose/análogos & derivados , Resinas Acrílicas/química , Sais/química , Derivados da Hipromelose/química , SolubilidadeRESUMO
Amorphous solid dispersions (ASDs) can be used to enhance the solubility and bioavailability of poorly soluble drugs. An ASD is often a ternary system containing a drug, a surfactant, and a polymer. Recent work on binary ASDs has observed significant differences between surface and bulk compositions, with impacts on wettability and stability. Here we investigate a ternary ASD composed of the antifungal posaconazole, the surfactant Span 80, and a dispersion polymer (PVP or PVP/VA). The surfactant loading was fixed at the typical level of 5 wt %, and the drug/polymer ratio was varied. We observed strong surface enrichment of the surfactant and simultaneous depletion of the drug. This effect is already pronounced in the binary drug-surfactant system and is enhanced by the addition of the polymers. Between the two polymers, the more hydrophilic PVP causes a stronger enhancement of the surface enrichment effect. These results demonstrate the impact of component interactions on the surface composition of ASDs and the performance.
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Interações Hidrofóbicas e Hidrofílicas , Polímeros , Solubilidade , Tensoativos , Tensoativos/química , Polímeros/química , Molhabilidade , Triazóis/química , Antifúngicos/química , Povidona/química , HexosesRESUMO
OBJECTIVE: This study aims to systematically evaluate the efficacy of probiotics in treating minimum hepatic encephalopathy (MHE). METHODS: A systematic search was conducted across three major databases: PubMed, China National Knowledge Infrastructure and Wanfang. The search period spanned from the inception of each database to 9 March 2023. The objective was to identify all randomised controlled trials (RCTs) examining the efficacy of probiotic preparations in treating MHE. The search terms included 'probiotics' along with other clinically relevant terms to comprehensively capture all pertinent studies. RESULTS: A total of 18 RCTs were included. The meta-analysis showed that probiotic treatment outperformed control groups in reducing blood ammonia levels (standard mean difference [MD] = -2.68, 95% confidence interval [CI]: -3.90 to -1.46, p < .0001), improving the remission rate of MHE (risk ratio [RR] = 2.79, 95% CI: 1.23-6.35, p = .01) and lowering alanine aminotransferase levels (MD = -11.10, 95% CI: -16.17 to -6.03, p < .0001). It also significantly reduced the Model for End-Stage Liver Disease scores (MD = -2.55, 95% CI: -3.56 to -1.54, p < .00001) and the incidence of MHE (RR = .18, 95% CI: .09-.34, p < .00001). CONCLUSION: Our study demonstrates that probiotics effectively improve blood ammonia levels, liver function and cognitive function in patients with MHE. They significantly enhance the remission rate of MHE and effectively reduce its incidence, providing solid new evidence for treating MHE with probiotics.
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AIMS: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections poses a significant threat to human health, necessitating urgent development of new antimicrobial agents. Silver nanoparticles (AgNPs), which are among the most widely used engineered nanomaterials, have been extensively studied. However, the impact of AgNPs on CRKP and the potential for drug resistance development remain inadequately explored. METHODS AND RESULTS: In this study, broth dilution method was used to determine the minimum inhibitory concentration (MIC) was determined using the broth dilution method. Results indicated MIC values of 93.1 ± 193.3 µg ml-1 for AgNPs, 2.3 ± 5.1 µg ml-1 for AgNO3, and 25.1 ± 48.3 µg ml-1 for imipenem (IMI). The combined inhibitory effect of AgNPs and IMI on CRKP was assessed using the checkerboard method. Moreover, after 6-20 generations of continuous culture, the MIC value of AgNPs increased 2-fold. Compared to IMI, resistance of Kl. pneumoniae to AgNPs developed more slowly, with a higher fold increase in MIC observed after 20 generations. Whole-genome sequencing revealed four nonsynonymous single nucleotide polymorphism mutations in CRKP after 20 generations of AgNP treatment. CONCLUSION: We have demonstrated that AgNPs significantly inhibit CRKP isolates and enhance the antibacterial activity of imipenem against Kl. pneumoniae. Although the development of AgNP resistance is gradual, continued efforts are necessary for monitoring and studying the mechanisms of AgNP resistance.
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Antibacterianos , Carbapenêmicos , Imipenem , Klebsiella pneumoniae , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Imipenem/farmacologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Prata/farmacologia , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/tratamento farmacológico , Humanos , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Farmacorresistência Bacteriana/genéticaRESUMO
OBJECTIVE: To review the effectiveness of different physical therapies for acute and sub-acute low back pain supported by evidence, and create clinical recommendations and expert consensus for physiotherapists on clinical prescriptions. DATA SOURCES: A systematic search was conducted in PubMed and the Cochrane Library for studies published within the previous 15 years. REVIEW METHODS: Systematic review and meta-analysis, randomized controlled trials assessing patients with acute and sub-acute low back pain were included. Two reviewers independently screened relevant studies using the same inclusion criteria. The Physiotherapy Evidence Database and the Assessment of Multiple Systematic Reviews tool were used to grade the quality assessment of randomized controlled trials and systematic reviews, respectively. The final recommendation grades were based on the consensus discussion results of the Delphi of 22 international experts. RESULTS: Twenty-one systematic reviews and 21 randomized controlled trials were included. Spinal manipulative therapy and low-level laser therapy are recommended for acute low back pain. Core stability exercise/motor control, spinal manipulative therapy, and massage can be used to treat sub-acute low back pain. CONCLUSIONS: The consensus statements provided medical staff with appliable recommendations of physical therapy for acute and sub-acute low back pain. This consensus statement will require regular updates after 5-10 years.
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Dor Lombar , Modalidades de Fisioterapia , Humanos , Dor Lombar/reabilitação , Dor Lombar/terapia , Consenso , Ensaios Clínicos Controlados Aleatórios como Assunto , Feminino , Dor Aguda/terapia , Dor Aguda/reabilitação , MasculinoRESUMO
Silver nanoparticles (AgNPs) have wide clinical applications because of their excellent antibacterial properties; however, they can cause liver inflammation in animals. Macrophages are among the main cells mediating inflammation and are also responsible for the phagocytosis of nanomaterials. The NLRP3 inflammasome is a major mechanism of inflammation, and its activation both induces cytokine release and triggers inflammatory cell death (i.e., pyroptosis). In previous studies, we demonstrated that mitophagy activation plays a protective role against AgNP-induced hepatotoxicity. However, the exact molecular mechanisms underlying these processes are not fully understood. In this study, we demonstrate that AgNP exposure induces NLRP3 inflammasome activation, mitochondrial damage and pyroptosis in vivo and in vitro. NLRP3 silencing or inhibiting mitochondrial reactive oxygen species (ROS) overproduction reduces PINK1-Parkin-mediated mitophagy. Meanwhile, the inhibition of mitophagy ROS production, mitochondrial, NLRP3-mediated inflammation, and pyroptosis in RAW264.7 cells were more pronounced than in the control group. These results suggest that PINK1-Parkin-mediated mitophagy plays a protective role by reducing AgNP-induced mitochondrial ROS and subsequent NLRP3 inflammasome activation.
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Doença Hepática Induzida por Substâncias e Drogas , Nanopartículas Metálicas , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Mitofagia , Inflamação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas QuinasesRESUMO
Physical vapor deposition can be used to prepare highly stable organic glass systems where the molecules show orientational and translational ordering at the nanoscale. We have used low-dose four-dimensional scanning transmission electron microscopy (4D STEM), enabled by a fast direct electron detector, to map columnar order in glassy samples of a discotic mesogen using a 2 nm probe. Both vapor-deposited and liquid-cooled glassy films show domains of similar orientation, but their size varies from tens to hundreds of nanometers, depending on processing. Domain sizes are consistent with surface-diffusion-mediated ordering during film deposition. These results demonstrate the ability of low-dose 4D STEM to characterize a mesoscale structure in a molecular glass system which may be relevant to organic electronics.
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As chloride (Cl-) is a commonly found anion in natural water, it has a significant impact on electrocatalytic oxidation processes; yet, the mechanism of radical transformation on different types of anodes remains unexplored. Therefore, this study aims to investigate the influence of chlorine-containing environments on the electrocatalytic degradation performance of levofloxacin using BDD, Ti4O7, and Ru-Ti electrodes. The comparative analysis of the electrode performance demonstrated that the presence of Cl- improved the removal and mineralization efficiency of levofloxacin on all the electrodes. The enhancement was the most pronounced on the Ti4O7 electrode and the least significant on the Ru-Ti electrode. The evaluation experiments and EPR characterization revealed that the increased generation of hydroxyl radicals and active chlorine played a major role in the degradation process, particularly on the Ti4O7 anode. The electrochemical performance tests indicated that the concentration of Cl- affected the oxygen evolution potentials of the electrode and consequently influenced the formation of hydroxyl radicals. This study elucidates the mechanism of Cl- participation in the electrocatalytic degradation of chlorine-containing organic wastewater. Therefore, the highly chlorine-resistant electrocatalytic anode materials hold great potential for the promotion of the practical application of the electrocatalytic treatment of antibiotic wastewater.
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BACKGROUND: Recent human and animal studies have demonstrated that Nod-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome is closely involved in the development of allergic diseases. OBJECTIVE: To identify the mechanism underlying the activation of NLRP3 inflammasome signaling pathway in an ovalbumin (OVA)-induced allergic rhinitis (AR) mice model and to validate the effect of a specific inhibitor of the NLRP3, MCC950. METHODS: Mice were divided into three groups and each group consisted of ten mice (saline group, the negative control group; OVA group, the OVA-induced AR model group; and OVA+MCC group, treated with 10 mg/kg MCC950). MCC950 was administered intraperitoneally every second day. Multiple parameters of AR, including NLRP3, caspase-1, interleukin (IL)-1ß, and IL-18 were evaluated by using ELISA, RT-qPCR, histopathology, and immunohistochemistry. RESULTS: The mRNA and protein levels of NLRP3, caspase-1, IL-1ß and IL-18 were upregulated in the OVA group compared with those of the saline group. MCC950 significantly inhibited the mRNA and protein levels of NLRP3, caspase-1, IL-1ß and IL-18 in nasal tissue. Further, AR symptoms and eosinophil count were normalized after MCC950 treatment. However, OVA-specific IgE was not restored in the OVA+MCC group. CONCLUSION: NLRP3 inflammasome signaling pathway may be an alternative pathway to induce AR symptoms in OVA-induced AR model. MCC950 is a specific inhibitor of NLRP3 cascade, which attenuates AR symptoms regardless of IgE.
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This study investigated the effect of trametenolic acid(TA) on the migration and invasion of human hepatocellular carcinoma HepG2.2.15 cells by using Ras homolog gene family member C(RhoC) as the target and probed into the mechanism, aiming to provide a basis for the utilization of TA. The methyl thiazolyl tetrazolium(MTT) assay was employed to examine the proliferation of HepG2.2.15 cells exposed to TA, and scratch and Transwell assays to examine the cell migration and invasion. The pull down assay was employed to determine the impact of TA on RhoC GTPase activity. Western blot was employed to measure the effect of TA on the transport of RhoC from cytoplasm to cell membrane and the expression of RhoC/Rho-associated kinase 1(ROCK1)/myosin light chain(MLC)/matrix metalloprotease 2(MMP2)/MMP9 pathway-related proteins. RhoC was over-expressed by transient transfection of pcDNA3.1-RhoC. The changes of F-actin in the cytoskeleton were detected by Laser confocal microscopy. In addition, the changes of cell migration and invasion, expression of proteins in the RhoC/ROCK1/MLC/MMP2/MMP9 pathway, and RhoC GTPase activity were detected. The subcutaneously transplanted tumor model of BALB/c nude mice and the low-, medium-, and high-dose(40, 80, and 120 mg·kg~(-1), respectively) TA groups were established and sorafenib(20 mg·kg~(-1)) was used as the positive control. The tumor volume and weight in each group were measured, and the expression of related proteins in the tumor tissue was determined by Western blot. The results showed that TA inhibited the proliferation of HepG2.2.15 cells in a concentration-dependent manner, with the IC_(50) of 66.65 and 23.09 µmol·L~(-1) at the time points of 24 and 48 h, respectively. The drug administration groups had small tumors with low mass. The tumor inhibition rates of sorafenib and low-, medium-and high-dose TA were 62.23%, 26.48%, 55.45%, and 62.36%, respectively. TA reduced migrating and invading cells and inhibited RhoC protein expression and RhoC GTPase activity in a concentration-dependent manner, dramatically reducing RhoC and membrane-bound RhoC GTPase. The expression of ROCK1, MLC, p-MLC, MMP2, and MMP9 downstream of RhoC can be significantly inhibited by TA, as confirmed in both in vitro and in vivo experiments. After HepG2.2.15 cells were transfected with pcDNA3.1-RhoC to overexpress RhoC, TA down-regulated the protein levels of RhoC, ROCK1, MLC, p-MLC, MMP2, and MMP9 and decreased the activity of RhoC GTPase, with the inhibition level comparable to that before overexpression. In summary, TA can inhibit the migration and invasion of HepG2.2.15 cells. It can inhibit the RhoC/ROCK1/MLC/MMP2/MMP9 signaling pathway by suppressing RhoC GTPase activity and down-regulating RhoC expression. This study provides a new idea for the development of autophagy modulators targeting HSP90α to block the proliferation and inhibit the invasion and migration of hepatocellular carcinoma cells via multiple targets of active components in traditional Chinese medicines.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Proteína de Ligação a GTP rhoC/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Metaloproteinase 9 da Matriz/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo , Sorafenibe , Camundongos Nus , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Linhagem Celular Tumoral , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Movimento Celular , Proliferação de CélulasRESUMO
This article analyzed the mechanism of Huangqi Simiao Decoction(HSD) for the treatment of type 2 diabetes mellitus(T2DM). The component targets of HSD and the related disease targets of T2DM were screened through network pharmacology. The protein-protein interaction(PPI) network of intersecting targets and the drug-component-intersecting target network were constructed to screen the potential active ingredients and targets. Molecular docking was performed using AutoDock Vina software to verify the interaction between potential components and core targets. The serum was tested by ultra performance liquid chromatography-tandem mass spectrometry, and multivariate statistical analyses, such as principal component analysis(PCA) and partial least squares discriminant analysis(PLS-DA), were used to search for the differential metabolites and related metabolic pathways of each group by combining with the MetaboAnalyst database. The same metabolic pathways were analyzed by combining the screened differential metabolites with the intersecting targets screened by network pharmacology. Network pharmacology showed that the nine core components of HSD for the treatment of T2DM were quercetin, kaempferol, stigmasterol, baicalein, ß-sitosterol, flavodoxin, canthaxanthin, canthaxanthin, berberine, and berberine, and the five core targets included AKT1, TP53, TNF, IL6, and VEGFA. Molecular docking showed that the core components bound well to the target genes. Metabolomics showed that a total of 112 common differential metabolites were identified, of which 88 metabolites exhibited increased concentration and 24 metabolites decreased concentration after treatment with HSD. Enrichment analysis showed that HSD regulated the body metabolism of patients with T2DM, mainly related to seven metabolic pathways, such as amino acid metabolism and tricarboxylic acid cycle. The joint analysis of metabolomics and network pharmacology showed that both involved histidine metabolism, arginine and proline metabolic pathways. This study suggests that HSD has a good efficacy for T2DM. Based on the combined analysis of metabolomics and network pharmacology, it was found that the mechanism may be that the pharmacodynamic bases of quercetin, kaempferol, and stigmasterol in HSD enhance the effects on histidine metabolism, arginine and proline metabolic pathways by modulating a variety of metabolites, which provides the basis for further prevention and treatment of T2DM.
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Diabetes Mellitus Tipo 2 , Medicamentos de Ervas Chinesas , Metabolômica , Farmacologia em Rede , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Simulação de Acoplamento MolecularRESUMO
Treatments for NSCLC patients with EGFR-TKI resistance are limited. Given that immunotherapy and antiangiogenic agents may have synergistic antitumor effects, we aimed to analyze the effect of multi-target angiogenesis inhibitor anlotinib and immune checkpoint inhibitors (ICIs) combination therapy in NSCLC patients who failed EGFR-TKI. The medical records of lung adenocarcinoma (LUAD) patients with EGFR-TKI resistance were reviewed. After EGFR-TKI resistance, patients who simultaneously received anlotinib and ICIs were enrolled in the observation group, and those who received platinum-pemetrexed chemotherapy were included in the control group. A total of 80 LUAD patients were reviewed and allocated to the anlotinib and ICIs combination therapy (n = 38) and chemotherapy (n = 42) groups. A re-biopsy was performed in all patients in the observation group before the administration of anlotinib and ICIs. The median follow-up was 15.63 months (95% CI: 12.19-19.08). Combination therapy exhibited better PFS (median PFS: 4.33 months [95% CI: 2.62-6.05] vs 3.60 months [95% CI: 2.48-4.73], P = .005), and better OS (median OS: 14.17 months [95% CI: 10.17-18.17] vs 9.00 months [95% CI: 6.92-11.08], P = .029) than chemotherapy. Most patients (73.7%) received combination therapy as fourth and later lines of therapy, with a median PFS of 4.03 months (95% CI: 2.05-6.02) and a median OS of 13.80 months (95% CI: 8.25-19.36). The disease control rate was 92.1%. Four patients discontinued the combination therapy due to adverse events, but the other adverse reactions were manageable and reversible. The combination of anlotinib and PD-1 inhibitors is a promising regimen for the late-line treatment of LUAD patients with EGFR-TKI resistance.
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Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
A lanthanide-based three-dimensional metal-organic framework with excellent water, acid/base, and solvent stability, namely {[(CH3)2NH2]0.7[Eu2(BTDBA)1.5(lac)0.7(H2O)2]·2H2O·2DMF·2CH3CN}n (JXUST-29, H4BTDBA = 4',4â´-(benzo[c][1,2,5]thiadiazole-4,7-diyl)bis([1,1'-biphenyl]-3,5-dicarboxylic acid), Hlac = lactic acid), has been synthesized and characterized. Since the N atoms of the thiadiazole group will not coordinate with lanthanide ions, JXUST-29 has a free basic N-site accessible to small H+ ions, which allows it to be used as a promising pH fluorescence sensor. Interestingly, the luminescence signal was significantly enhanced, with an approximately 54-fold enhancement in the emission intensity when the pH value was increased from 2 to 5, which is the typical behavior of pH probes. In addition, JXUST-29 can also be used as a luminescence sensor to detect l-arginine (Arg) and l-lysine (Lys) in an aqueous solution through fluorescence enhancement and the blue-shift effect. The detection limits were 0.023 and 0.077 µM, respectively. In addition, JXUST-29-based devices were designed and developed to facilitate detection. Importantly, JXUST-29 is also capable of detecting and sensing Arg and Lys in living cells.
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Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Lisina , Elementos da Série dos Lantanídeos/química , Íons , Água/química , Concentração de Íons de HidrogênioRESUMO
Influenza virus infection can cause kidney damage. However, the link between influenza infection and disease is still unclear. The purpose of this study was to analyze the relationship between heterophilic epitopes on H5N1 hemagglutinin (HA) and disease. The monoclonal antibody (mAb) against H5N1 was prepared, mAbs binding to human kidney tissue were screened, and the reactivities of mAbs with five different subtypes of influenza virus were detected. Design and synthesize the peptides according to the common amino acid sequence of these antigens, and analyze the distribution of the epitope on the crystal structure of HA. Immunological methods were used to detect whether the heterophilic epitopes could induce the production of antibodies that cross-react with kidney tissue. The results showed that H5-30 mA b binding to human kidney tissue recognized the heterophilic epitope 191-LVLWGIHHP-199 on the head of HA. The key amino acid were V192, L193, W194 and I196, which were highly conserved in human and avian influenza virus HA. The heterophilic epitope could induce mice to produce different mAbs binding to kidney tissue. Such heterophilic antibodies were also detected in the serum of the patients. It can provide materials for the mechanism of renal diseases caused by influenza virus infection.
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Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Humanos , Animais , Camundongos , Epitopos , Hemaglutininas , Mapeamento de Epitopos/métodos , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Anticorpos Antivirais , Anticorpos Monoclonais , RimRESUMO
Amorphous drugs are used to improve bioavailability of poorly water-soluble drugs. Crystallization must be managed to take full advantage of this formulation strategy. Crystallization of amorphous drugs proceeds in a sequence of crystal nucleation and growth, with different kinetics. At low temperatures, crystal nucleation is fast, but crystal growth is slow. Therefore, amorphous drugs may generate dense but nanoscale crystal nuclei. Such tiny nuclei cannot be detected using routine powder X-ray diffraction (PXRD) and polarized light microscopy (PLM). However, they may negate the dissolution advantage of amorphous drugs. In this work, for the first time, the impact of crystal nuclei on dissolution of amorphous drugs was studied by monitoring the real-time dissolution from amorphous drug films, with and without crystal nuclei, and the evolving crystallinity in the films. Three model drugs (ritonavir/RTV, posaconazole/POS, and nifedipine/NIF) were chosen to represent different crystallization tendencies in the supercooled liquid state, namely, slow-nucleation-and-slow-growth (SN-SG), fast-nucleation-and-slow-growth (FN-SG), and fast-nucleation-and-fast-growth (FN-FG), respectively. We find that although the amorphous films containing nuclei do not show obvious differences from the nuclei-free films under PLM and PXRD before dissolution, they have inferior dissolution performance relative to the nuclei-free amorphous films. For SN-SG drug RTV, crystal nuclei have negligible impact on the crystallization of amorphous films, dissolution rate, and supersaturation achieved. However, they cause earlier de-supersaturation by inducing crystallization in solution as heterogeneous seeds. For FN-SG drug POS and FN-FG drug NIF, crystal nuclei accelerate crystallization in the amorphous films leading to lower supersaturation achieved with POS, and elimination of any supersaturation with NIF. Dissolution profiles of amorphous films can be further analyzed using a derivative function of the apparent dissolution rate, which yields amorphous solubility, initial intrinsic dissolution rate, and onset of crystallization in the amorphous films. This study highlights that although crystal nuclei are undetectable with routine analytical methods, they can significantly negate, or even eliminate, the dissolution advantage of amorphous drugs. Hence, understanding crystal nucleation process and developing approaches to prevent it are necessary to fully realize the benefits of amorphous solids.
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Ritonavir , Solubilidade , Cristalização , Ritonavir/química , Difração de Raios XRESUMO
An amorphous drug-polymer salt (ADPS) can be remarkably stable against crystallization at high temperature and humidity (e.g., 40°C/75% RH) and provide fast release. Here, we report that process conditions strongly influence the degree of proton transfer (salt formation) between a drug and a polymer and in turn the product's stability and release. For lumefantrine (LMF) formulated with poly(acrylic acid) (PAA), we first show that the amorphous materials prepared by slurry conversion and antisolvent precipitation produce a single trend in which the degree of drug protonation increases with PAA concentration from 0% for pure LMF to â¼100% above 70 wt % PAA, independent of PAA's molecular weight (1.8, 450, and 4000 kg/mol). This profile describes the equilibrium for salt formation and can be modeled as a chemical equilibrium in which the basic molecules compete for the acidic groups on the polymer chain. Relative to this equilibrium, the literature methods of hot-melt extrusion (HME) and rotary evaporation (RE) reached much lower degrees of salt formation. For example, at 40 wt % drug loading, HME reached 5% salt formation and RE 15%, both well below the equilibrium value of 85%. This is noteworthy given the common use of HME and RE in manufacturing amorphous formulations, indicating a need for careful control of process conditions to ensure the full interaction between the drug and the polymer. This need arises due to the low mobility of macromolecules and the mutual hindrance of adjacent reaction sites. We find that a high degree of salt formation enhances drug stability and release. For example, at 50% drug loading, an HME-like formulation with 19% salt formation crystallized faster and released only 20% of the drug relative to a slurry-prepared formulation with 70% salt formation. Based on this work, we recommend slurry conversion as the method for preparing ADPS for its ability to enhance salt formation and continuously adjust drug loading. While this work focused on salt formation, the impact of process conditions on the molecular-level interactions between a drug and a polymer is likely a general issue for amorphous solid dispersions, with consequences on product stability and drug release.
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Polímeros , Prótons , Polímeros/química , Sais , Química Farmacêutica/métodos , Solubilidade , Lumefantrina , Estabilidade de Medicamentos , Composição de Medicamentos/métodosRESUMO
A novel endophytic bacterium, designated strain BGMRC 0089T, was isolated from a surface-sterilized root of Sonneratia apetala. Cells were observed to be Gram-negative, rod-shaped and motile with polar flagella. Strain BGMRC 0089T was found to grow optimally at 28-30 °C, pH 7.0-8.0 and in the presence of 1â% (w/v) NaCl. Strain BGMRC 0089T contained ubiquinone Q-10 and the predominant fatty acid was summed feature 8. The polar lipid profile of strain BGMRC 0089T was found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmonomethylethanolamine and phosphatidylethanolamine. Based on the results of 16S rRNA gene analysis, this isolate has the closest phylogenetic relationships with Rhizobium lemnae L6-16T (96.5â%) and Allorhizobium oryziradicis N19T (96.4â%). Average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values of the isolate with the type strains of the genera Rhizobium and Allorhizobium were below 84.6, 73.9 and 22.1ââ%, respectively. Analysis the 4.55 Mb draft genome of strain BGMRC 0089T revealed several plant-associated genes, which may play important roles for the plant in the adaptation to the mangrove habitat. Based on its distinct phylogenetic, phenotypic and chemotaxonomic characteristics, strain BGMRC 0089T is proposed to represent a novel Allorhizobium species, for which the name Allorhizobium sonneratiae sp. nov. is proposed (type strain BGMRC 0089T=DSM 100171T=MCCC 1K04805T).
Assuntos
Ácidos Graxos , Rhizobium , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Composição de Bases , DNA Bacteriano/genética , Rhizobium/genética , ChinaRESUMO
A taxonomic study was carried out on strain BGMRC 0090T, which was isolated from seawater. The isolate was a Gram-negative, aerobic, flagellated, rod-shaped bacterium with algicidal activity. Optimal growth was observed at 30 °C, pH 6.0 and with 2â% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BGMRC 0090T belonged to the genus Parvularcula, with highest sequence similarity to Parvularcula lutaonensis CC-MMS-1T (98.4â%). Average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values between strain BGMRC 0090T and five strains of the genus Parvularcula with publicly available genomes were below 84.0, 69.2 and 21.4â%, respectively. The genome of strain BGMRC 0090T was 3.2 Mb with 64.8 mol% DNA G+C content and encoded 2905 predicted proteins, three rRNA, 42 tRNA and four ncRNA genes. Some algicidal biosynthesis-associated genes were detected in the genome. Strain BGMRC 0090T contained Q-10 as the major quinone. The predominant fatty acids were identified as summed feature 8 (C18â:â1ω7c/ω6c) and C16â:â0. Based on the polyphasic evidence presented in this paper, strain BGMRC 0090T is concluded to represent a novel species of the genus Parvularcula, for which the name Parvularcula maris sp. nov. is proposed. The type strain is BGMRC 0090T (= KCTC 92591T=MCCC 1K08100T).
Assuntos
Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/química , Filogenia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Água do Mar/microbiologiaRESUMO
During a survey of thermotolerant fungi in China, three isolates were obtained from soil samples. Phylogenetic analysis of a combined internal transcribed spacer and large subunit dataset showed that these isolates belong to the same species, which form a well-separated lineage distinct from the other genera in Latoruaceae. Morphologically, the isolates are characterized by having globose and smooth conidiogenous cells, verruculose mycelium and cymbiform conidia. Combining the phylogenetic analyses and morphological characteristics, Multiverruca gen. nov. is proposed and introduced to accommodate a single new species, Multiverruca sinensis sp. nov. Detailed descriptions, illustrations and notes are provided for the new genus and species.
Assuntos
Ascomicetos , Solo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Composição de Bases , Ácidos Graxos/químicaRESUMO
Aim: To elucidate the clinicopathological and prognostic values of interferon regulatory factor (IRF) family genes in acute myeloid leukemia (AML). Patients & methods: Differential expression analysis and survival analysis from several reliable databases were conducted and further validated using patients with AML. Results: The expression level of IRF1/2/4/5/7/8/9 in patients with AML was upregulated, while IRF3/6 expression was downregulated. High IRF1/7/9 expression indicated a worse overall survival rate. Conclusion: Overexpression of IRF1/7/9 may be associated with poor survival in patients with AML, suggesting that the IRF family may be a promising therapeutic target.