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1.
J Mater Chem B ; 12(21): 5111-5127, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38687208

RESUMO

Recently, bacterial infections have become a global crisis, greatly threatening the health of human beings. The development of a non-antibiotic biomaterial is recognized as an alternative way for the effective treatment of bacterial infections. In the present work, a multifunctional copper peroxide (CP) nanodot-decorated gold nanostar (GNS)/silica nanorod (SiNR) Janus nanostructure (GNS@CP/SiNR) with excellent antibacterial activity was reported. Due to the formation of the Janus nanostructure, GNS@CP/SiNR displayed strong plasmonic resonance absorbance in the near infrared (NIR)-II region that enabled the nanosystem to achieve mild photothermal therapy (MPTT). In acidic conditions, CP decorated on GNS@CP/SiNR dissociated rapidly by releasing Cu2+ and H2O2, which subsequently transformed to ˙OH via the Fenton-like reaction for chemodynamic therapy (CDT). As a result, GNS@CP/SiNR could effectively inhibit both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), and eradicate the associated bacterial biofilms by exerting the synergistic MPTT/CDT antibacterial effect. Moreover, GNS@CP/SiNR was also demonstrated to be effective in treating wound infections, as verified on the S. aureus-infected full thickness excision wound rat model. Our mechanism study revealed that the synergistic MPTT/CDT effect of GNS@CP/SiNR firstly caused bacterial membrane damage, followed by boosting intracellular ROS via the severe oxidative stress effect, which subsequently caused the depletion of intracellular GSH and DNA damage, finally leading to the death of bacteria.


Assuntos
Antibacterianos , Cobre , Escherichia coli , Ouro , Radical Hidroxila , Nanotubos , Dióxido de Silício , Staphylococcus aureus , Ouro/química , Ouro/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Animais , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Nanotubos/química , Radical Hidroxila/metabolismo , Radical Hidroxila/química , Cobre/química , Cobre/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Ratos , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Terapia Fototérmica , Raios Infravermelhos , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Ratos Sprague-Dawley , Biofilmes/efeitos dos fármacos
2.
Curr Eye Res ; 49(4): 368-379, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38164922

RESUMO

PURPOSE: Circular RNAs (circRNAs) are products of alternative splicing with roles as competitive endogenous RNAs or microRNA sponges, regulating gene expression and biological processes. However, the involvement of circRNAs in herpes simplex keratitis remains largely unexplored. METHODS: This study examines circRNA and miRNA expression profiles in primary human corneal epithelial cells infected with HSV-1, compared to uninfected controls, using microarray analysis. Bioinformatic analysis predicted the potential function of the dysregulated circRNAs and microRNA response elements (MREs) in these circRNAs, forming an interaction network between dysregulated circRNAs and miRNAs. RESULTS: A total of 332 circRNAs and 16 miRNAs were upregulated, while 80 circRNAs and six miRNAs were downregulated (fold change ≥2.0 and p < 0.05). Gene ontology (GO) and KEGG pathway analyses were performed on parental genes of dysregulated circRNAs to uncover potential functions in HSV-1 infection. Notably, miR-181b-5p, miR-338-3p, miR-635, and miR-222-3p emerged as pivotal miRNAs interacting with multiple dysregulated circRNAs. CONCLUSIONS: This comprehensive study offers insights into differentially expressed circRNAs and miRNAs during HSV-1 infection in corneal epithelial cells, shedding light on circRNA-miRNA interactions' potential role in herpes simplex keratitis pathogenesis.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Ceratite Herpética , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , Herpesvirus Humano 1/genética , Células Epiteliais/metabolismo , Ceratite Herpética/genética
3.
MAbs ; 15(1): 2292305, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38095560

RESUMO

Pharmaceutical companies have recently focused on accelerating the timeline for initiating first-in-human (FIH) trials to allow quick assessment of biologic drugs. For example, a stable cell pool can be used to produce materials for the toxicology (Tox) study, reducing time to the clinic by 4-5 months. During the coronavirus disease 2019 (COVID-19) pandemic, the anti-COVID drugs timeline from DNA transfection to the clinical stage was decreased to 6 months using a stable pool to generate a clinical drug substrate (DS) with limited stability, virus clearance, and Tox study package. However, a lean chemistry, manufacturing, and controls (CMC) package raises safety and comparability risks and may leave extra work in the late-stage development and commercialization phase. In addition, whether these accelerated COVID-19 drug development strategies can be applied to non-COVID projects and established as a standard practice in biologics development is uncertain. Here, we present a case study of a novel anti-tumor drug in which application of "fast-to-FIH" approaches in combination with BeiGene's de-risk strategy achieved successful delivery of a complete CMC package within 10 months. A comprehensive comparability study demonstrated that the DS generated from a stable pool and a single-cell-derived master cell bank were highly comparable with regards to process performance, product quality, and potency. This accomplishment can be a blueprint for non-COVID drug programs that approach the pace of drug development during the pandemic, with no adverse impact on the safety, quality, and late-stage development of biologics.


Assuntos
Antineoplásicos , Produtos Biológicos , COVID-19 , Humanos , Anticorpos Monoclonais , Preparações Farmacêuticas , Antineoplásicos/uso terapêutico
4.
J Mater Chem B ; 11(7): 1495-1505, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36655922

RESUMO

Currently, multidrug resistant (MDR) bacterial infections are a great threat to public health, and the development of novel strategies for high efficiency combatting of MDR bacteria is in urgent demand. Hydrogen (H2) is a small gas with a high reducing ability, and plenty of recent studies have demonstrated its therapeutic effect on many diseases. However, the antibacterial effectiveness and mechanism of H2 against MDR bacteria are still unknown. In the present work, using PdH nanohydride with a temperature responsive H2-releasing property as the H2 source, we demonstrated that H2 was not only able to inhibit the growth of normal Staphylococcus aureus (S. aureus), but could also effectively eliminate single drug resistant S. aureus (CRSA) and multidrug resistant S. aureus (MRSA), as well as the biofilms formed by those bacteria. Moreover, an in-depth mechanism regarding the anti-antibiotic-resistance activity of H2 was elucidated by us, in which H2 exerted its antibacterial effect by firstly causing severe membrane damage, followed by boosting generation of intracellular ROS, which subsequently triggered DNA damage and finally led to bacterial death. The proposed mechanism was further verified by genomic analysis, where a cluster of genes related to bacterial membrane integrity, biofilm formation, metabolism and DNA functions was significantly perturbed by the released H2. In particular, H2 boosted intracellular ROS generation by destroying the redox homeostasis of bacterial metabolism. More importantly, we revealed that H2 was able to alleviate the antibiotic resistance of CRSA and MRSA by significantly down-regulating the expression of many drug-resistant genes, e.g. the norG gene of CRSA, and fmtA, gpsB, sarA and marR genes of MRSA, as well as reducing the minimal inhibitory concentration (MIC) of ciprofloxacin/ampicillin against CRSA/MRSA. The findings in our work suggested that H2 therapy is a promising tool for combating antibiotic-resistant bacteria.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Espécies Reativas de Oxigênio , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico
5.
Nanoscale ; 13(25): 11169-11187, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34137412

RESUMO

Recently, alkyl radicals have attracted much attention in cancer therapy due to their oxygen-independent generation property. For the first time, alkyl radical and nitric oxide (NO) combined therapy is demonstrated as an effective strategy for tumor inhibition. As a proof of concept, a biocompatible free radical nanogenerator with near-infrared (NIR) II laser-induced simultaneous NO and alkyl radical release property was elaborately fabricated. In particular, an NIR II molecule (IR 1061), NO donor (BNN6) and alkyl radical initiator (AIPH) were firstly encapsulated in a natural lecithin stabilized phase change material, and then further functionalized by an amphiphile of DSPE-PEG-RGD with specific tumor targeting ability, finally obtaining biocompatible P(IR/BNN6/AIPH)@Lip-RGD. Upon NIR II laser irradiation, the photothermal effect generated from IR 1061 could trigger the phase change of the nanogenerator by releasing the encapsulated BNN6 and AIPH, and subsequently decompose them to generate highly active NO and alkyl radicals. Remarkably, NO and alkyl radical release profiles of P(IR/BNN6/AIPH)@Lip-RGD could be precisely controlled using intermittent NIR II laser irradiation. Moreover, P(IR/BNN6/AIPH)@Lip-RGD displayed a synergistic NO and alkyl radicals' anticancer effect by significantly inhibiting the growth of breast tumors, upon NIR II laser exposure. Furthermore, an in depth mechanistic study revealed that synergistic NO and alkyl radical effect induced cancer cell apoptosis through a mitochondria-mediated apoptotic pathway. The synergistic effect jointly caused a burst generation of mitochondrial ROS, which significantly down-regulated Bcl-2 protein expression, accelerated cytochrome c release and triggered a cascade of apoptosis-related proteins of Caspase-3 and Caspase-9.


Assuntos
Neoplasias da Mama , Nanopartículas , Apoptose , Linhagem Celular Tumoral , Feminino , Radicais Livres , Humanos , Raios Infravermelhos , Lasers , Óxido Nítrico
6.
J Agric Food Chem ; 68(31): 8286-8294, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32640796

RESUMO

Diabetic cataract is one of the most important causes of blindness worldwide. Cyanidin-3-O-glucoside (C3G) is found to exert beneficial effects on many diabetic complications. However, its effect on diabetic cataract is not well known. Herein, we investigated the effect of C3G on high glucose-induced lens epithelial cell (SRA01/04) apoptosis and cataract formation as well as the involved mechanisms. We found C3G (20 µM) could preserve cell viability in SRA01/04 cells exposed to high glucose (100 µM). Meanwhile, C3G inhibited SRA01/04 cell apoptosis and regulated the Bcl-2/Bax ratio. Additionally, C3G suppressed NF-κB activation and subsequent cyclooxygenases-2 (Cox-2) expression, which are associated with the protection against apoptosis. Moreover, C3G attenuated lens opacity and protein aggregation in lens culture exposed to high glucose. In conclusion, C3G protected against high glucose-induced SRA01/04 cell apoptosis and cataract formation, which indicated the potential protection of anthocyanins on diabetic cataract.


Assuntos
Antocianinas/administração & dosagem , Catarata/prevenção & controle , Ciclo-Oxigenase 2/metabolismo , Retinopatia Diabética/prevenção & controle , Glucose/efeitos adversos , NF-kappa B/metabolismo , Animais , Apoptose/efeitos dos fármacos , Catarata/metabolismo , Catarata/fisiopatologia , Ciclo-Oxigenase 2/genética , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Retinopatia Diabética/fisiopatologia , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Humanos , Cristalino/citologia , Cristalino/efeitos dos fármacos , Cristalino/metabolismo , NF-kappa B/genética , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
7.
J Cell Physiol ; 235(6): 5130-5140, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691974

RESUMO

Inflammation is considered to be critical in the pterygium progression and recurrence. However, the underlying molecular mechanism is not well understood. Herein, we investigated the potential role of RNA binding protein human antigen R (HuR) responsible for the impact of inflammation on pterygium development. The expression of HuR and matrix metallopeptidase-9 (MMP-9) in pterygium and normal conjunctiva was detected with immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The influence of interleukin-1ß (IL-1ß) on HuR expression and cellular distribution was determined with western blot and immunofluorescence. The pterygium fibroblast (PTF) migration was determined with scratch wound healing assay and Transwell migration assay. MMP-9 production was determined with qRT-PCR and gelatin zymography. The interaction between HuR and MMP-9 was investigated with RNP immunoprecipitation (IP) followed by RT-PCR and messenger RNA (mRNA) stability analysis. HuR and MMP-9 expression are elevated in pterygium, especially progressive pterygium compared with normal conjunctiva. IL-1ß could increase the expression and nucleus-cytoplasm shuttle of HuR in cultured PTFs. HuR mediated the stimulatory effect of IL-1ß on PTF migration and MMP-9 production. HuR bound to MMP-9 mRNA and in turn increased it stability. Our results suggest that posttranscriptional regulation of MMP-9 via stabilizing mRNA by HuR might contribute to the stimulatory effect of inflammatory factor IL-1ß on pterygium progression. These findings shed light on the pathogenesis of pterygium and provide a promising target for adjuvant treatment of pterygium.


Assuntos
Proteína Semelhante a ELAV 1/genética , Inflamação/genética , Interleucina-1beta/genética , Metaloproteinase 9 da Matriz/genética , Pterígio/genética , Idoso , Movimento Celular/genética , Túnica Conjuntiva/crescimento & desenvolvimento , Túnica Conjuntiva/patologia , Progressão da Doença , Feminino , Fibroblastos/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Processamento de Proteína Pós-Traducional/genética , Pterígio/metabolismo , Pterígio/patologia , Estabilidade de RNA/genética
8.
Curr Eye Res ; 43(12): 1422-1431, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30032655

RESUMO

PURPOSE: Long noncoding RNAs (lncRNAs) have been demonstrated to have important regulatory functions in diverse cellular processes; however, the role of lncRNAs in the pathogenesis of herpes simplex keratitis (HSK) remains poorly understood. METHODS: Primary human corneal epithelial cells (HCECs) were infected with herpes simplex virus-1 (HSV-1) and the total RNAs extracted from both the infected group and the mock-infected group subjected to microarray analysis to identify the differential expression of lncRNAs and mRNAs. We also performed bioinformatic analysis including gene ontology (GO) analysis, pathway analysis and co-expression network analysis. RESULTS: Compared with mock-infected group, the expression of thousands of lncRNAs and mRNAs were significantly changed, and the microarray results were validated by qRT-PCR. The most enriched GOs targeted by up-regulated transcripts were defense response, intrinsic component of plasma membrane and cytokine activity,and the most enriched GOs targeted by the down-regulated transcripts were cellular metabolic process, intracellular part and poly (A) RNA binding. Pathway analysis indicated that the most correlated pathways for up- and down-regulated transcripts were cytokine-cytokine receptor interaction and RNA transport, respectively. CONCLUSIONS: Our study identified the genome-wide profile of lncRNAs and mRNAs expression in primary corneal epithelial cells with HSV-1 infection. These transcriptomic data together with subsequent bioinformatic analysis will provide us with novel clue to the insight into molecular mechanism and potential therapeutic targets of HSK. Further studies are expected to verify the potentially functional genes and pathways and explore the critical lncRNAs. ABBREVIATIONS: Long noncoding RNAs: lncRNAs; herpes simplex virus-1: HSV-1; herpes simplex virus keratitis: HSK; human corneal epithelial cells: HCECs.


Assuntos
Epitélio Corneano/metabolismo , Infecções Oculares Virais/genética , Perfilação da Expressão Gênica/métodos , Herpesvirus Humano 1 , Ceratite Herpética/genética , RNA Longo não Codificante/genética , Transcriptoma/genética , Células Cultivadas , Regulação para Baixo , Epitélio Corneano/patologia , Epitélio Corneano/virologia , Infecções Oculares Virais/metabolismo , Infecções Oculares Virais/patologia , Humanos , Ceratite Herpética/metabolismo , Ceratite Herpética/patologia , RNA Longo não Codificante/metabolismo , Regulação para Cima
9.
Nanotoxicology ; 12(4): 312-324, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29463199

RESUMO

BACKGROUND: Cornea is the outmost structure of the eye and exposed directly to the air pollution. However, little is known about the effect of PM2.5 on corneal epithelium, which is critical for maintenance of cornea homeostasis and visual function. OBJECTIVE: We investigated the influence of PM2.5 exposure on corneal epithelial migration and the possible mechanisms involved in the process. METHODS: We observed wound healing in mouse model of cornea abrasion, evaluated the migration and mobility of cultured corneal epithelial cells with wound scratch assay and Transwell migration assay, detected the phosphorylation and interaction of FAK/paxillin with immunofluorescence and immunoprecipitation, and determined the RhoA activity and actin reorganization, in response to PM2.5 exposure. RESULTS: Exposure to PM2.5 remarkably inhibited corneal epithelial cell migration both in mouse model of corneal abrasion and in cell culture model. We found the phosphorylation and interaction of FAK/paxillin, RhoA activity as well as actin reorganization were suppressed by PM2.5 exposure. Moreover, formation of ROS might play a role in the action of PM2.5. CONCLUSIONS: PM2.5 exposure could result in delay of corneal epithelium wound healing by inhibiting cell migration, thus more attention should be paid to the potential risk of corneal infection and effort should be made to protect eyes against impairment induced by PM2.5.


Assuntos
Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Epitélio Corneano/efeitos dos fármacos , Epitélio Corneano/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Material Particulado/toxicidade , Proteína rhoA de Ligação ao GTP/metabolismo , Actinas/metabolismo , Animais , Células Epiteliais/efeitos dos fármacos , Epitélio Corneano/citologia , Epitélio Corneano/enzimologia , Humanos , Camundongos , Paxilina/metabolismo , Fosforilação , Transdução de Sinais , Cicatrização/efeitos dos fármacos
10.
Int J Ophthalmol ; 10(6): 973-981, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28730091

RESUMO

Pterygium is a common ocular surface disease induced by a variety of factors. The exact pathogenesis of pterygium remains unclear. Numbers of genes and proteins are discovered in pterygium and they function differently in the occurrence and development of this disease. We searched the Web of Science and PubMed throughout history for literatures about the subject. The keywords we used contain pterygium, gene, protein, angiogenesis, fibrosis, proliferation, inflammation, pathogenesis and therapy. In this review, we summarize the aberrant expression of a range of genes and proteins in pterygium compared with normal conjunctiva or cornea, including growth factors, matrix metalloproteinases and tissue inhibitors of metalloproteinases, interleukins, tumor suppressor genes, proliferation related proteins, apoptosis related proteins, cell adhesion molecules, extracellular matrix proteins, heat shock proteins and tight junction proteins. We illustrate their possible mechanisms in the pathogenesis of pterygium as well as the related intervention based on them for pterygium therapy.

11.
Invest Ophthalmol Vis Sci ; 57(7): 3093-102, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27286367

RESUMO

PURPOSE: To assess the genotoxic effect of airborne particulate matter on corneal epithelial cells and investigate the role of reactive oxygen species (ROS) formation in this process. METHODS: Immortalized human corneal epithelial cells (HCECs) and primary bovine corneal epithelial cells were exposed to airborne particulate matter collected from Guangzhou for 24 hours. The cell viability and toxicity were measured by the CCK-8 test and lactate dehydrogenase (LDH) release, respectively. The DNA breaks and DNA repair were examined by alkaline comet assay and by immunofluorescence staining of the phosphorylated histone variant H2AX (γH2AX), respectively. Reactive oxygen species production was assessed by the fluorescent probe, CM-H2DCFDA. Cell senescence was evaluated with senescence-associated ß-Galactosidase staining, and cell ultrastructure was observed with transmission electron microscopy. RESULTS: Exposure to PM2.5 at the concentration of 20 µg/mL to 200 µg/mL decreased cell viability and increased LDH release. Remarkably increased DNA double-stand breaks, increased expression of DNA repair-related protein γH2AX, elevated ROS formation, and altered cell ultrastructure were observed in HCECs after treatment with PM2.5. The genotoxic effect of PM2.5 was attenuated by the ROS inhibitor N-acetyl-l-cysteine (NAC). CONCLUSIONS: Particulate matter 2.5 could induce DNA damage and cell senescence in corneal epithelial cells, probably by promoting ROS formation. Thus, whether long-term exposure of PM2.5 might be related to potential risk of abnormality in corneal epithelium renewal and regeneration should be further investigated.


Assuntos
Poluição do Ar/efeitos adversos , Senescência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Epitélio Corneano/citologia , Material Particulado/toxicidade , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , China , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Epitélio Corneano/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/metabolismo
12.
J Pharm Sci ; 101(12): 4597-607, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23027587

RESUMO

Multivariate data analysis methods such as partial least square (PLS) modeling have been increasingly applied to pharmaceutical product development. This study applied the PLS modeling to analyze a product development dataset generated from a design of experiment and historical batch data. Attention was paid in particular to the assessment of the importance of predictor variables, and subsequently the variable selection in the PLS modeling. The assessment indicated that irrelevant and collinear predictors could be extensively present in the initial PLS model. Therefore, variable selection is an important step in the optimization of the pharmaceutical product process model. The variable importance for projections (VIP) and coefficient values can be employed to rank the importance of predictors. On the basis of this ranking, the irrelevant predictors can be removed. To further reduce collinear predictors, multiple rounds of PLS modeling on different combinations of predictors may be necessary. To this end, stepwise reduction of predictors based on their VIP/coefficient ranking was introduced and was proven to be an effective approach to identify and remove redundant collinear predictors. Overall, the study demonstrated that the variable selection procedure implemented herein can effectively evaluate the importance of variables and optimize models of drug product processes.


Assuntos
Química Farmacêutica/métodos , Análise Multivariada , Análise dos Mínimos Quadrados , Modelos Químicos , Modelos Estatísticos
13.
J Pharm Sci ; 101(5): 1865-76, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22290332

RESUMO

One common challenge in pharmaceutical product development is mapping the potential effects of a large number of variables. Conventional experimental tools such as design-of-experiment (DoE) approach demand study scales too large to be practical. In comparison, nonexperimental studies have the advantage to evaluate a large number of variables, but may suffer from the inability to define causal relationships. Given this situation, the current study sought to divide the mapping operation into two steps. The first step screens out potential significant variables and confirms the causal relationships, and the second step involves DoE studies to define the design space. This report demonstrates that nonexperiments can be effectively applied in the first step. The screening task was performed on the nonexperimental dataset consisting of data collected from historical batches manufactured as clinical testing materials. A combination of statistical analysis and technical assessment was applied in the screening. By invoking the variable selection procedure embedded in the multivariate regression analysis, the significance of variables to the responses was assessed. Potential technical mechanisms and variable confounding were then examined for the significant correlations identified. Experimental confirmation was performed to confirm the causal relationships. The last two measures were introduced to remedy the weakness of the nonexperiments in defining causal relationships. Through this effort, the relationships among a large number of variables were quantitatively evaluated and the variables of potential risks to product quality and manufacturability were identified. The results effectively directed further DoE studies to the high-risk variables. Overall, the nonexperimental analysis improve the mapping efficiency and may provide a data-driven decision-making platform to enhance quality risk assessment.


Assuntos
Interpretação Estatística de Dados , Causalidade , Tamanho da Partícula , Solubilidade
14.
J Pharm Sci ; 101(1): 312-21, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21918985

RESUMO

In quality by design (QbD) paradigm, specifications on active pharmaceutical ingredients (APIs) are a critical component of the overall control strategy to ensure drug product quality. In establishing appropriate specifications for highly correlated API properties, multivariate specifications were advocated recently (Duchesne C, MacGregor JF. 2004. J Qual Technol 36:78-94). In this text, we reviewed several scenarios where API properties are of varying degrees of intercorrelation, and discussed the corresponding control strategies. One scenario was further analyzed, in which high degree of property intercorrelation could afford a single univariate specification and, thereby, simplify the control strategy. In the case study provided, we first mapped the potential design space of the API physical properties, and subsequently compared the effectiveness of univariate and multivariate control strategies. On the basis of the comparison, a single univariate control scheme was proposed and boundary was defined. Finally, width of the design space for API physical properties was assessed, and the effectiveness of the API manufacturing process control was preliminarily evaluated.


Assuntos
Preparações Farmacêuticas/química , Química Farmacêutica/métodos , Controle de Qualidade
15.
Drug Metab Dispos ; 38(7): 1029-38, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20406853

RESUMO

Factors determining the pharmacokinetics of 2-chloro-N-(4-chloro-3-(pyridine-2-yl)phenyl)-4-(methylsulfonyl)benzamide (GDC-0449) were investigated using preclinical studies and physiologically based pharmacokinetic (PBPK) modeling. Multiple-dose studies where dogs were given twice-daily oral doses of either 7.5 or 25 mg/kg GDC-0449 showed less than dose-proportional increases in exposure on day 1. At steady state, exposures were comparable between the two dose groups. Oral administration of activated charcoal to dogs receiving oral or intravenous GDC-0449 (25 mg) showed a more rapid decrease in plasma concentrations, suggesting that the concentration gradient driving intestinal membrane permeation was reversible. The biliary clearance of GDC-0449 in dogs was low (0.04 ml/min/kg) and did not account for the majority of the estimated systemic clearance (approximately 19% of systemic clearance). Likewise, in vitro studies using sandwich-cultured human hepatocytes showed negligible biliary excretion. The effect of particle size on oral absorption was shown in a single-dose study where 150 mg of GDC-0449 of two particle sizes was administered. An oral PBPK model was used to investigate mechanisms determining the oral pharmacokinetics of GDC-0449. The overall oral absorption of GDC-0449 appears to depend on the interplay between the dissolution and intestinal membrane permeation processes. A unique feature of GDC-0449 distinguishing it from other Biopharmaceutical Classification System II compounds was that incorporation of the effects of solubility rate-limited absorption and nonsink permeation on the intestinal membrane permeation process was necessary to describe its pharmacokinetic behavior.


Assuntos
Anilidas/química , Anilidas/farmacocinética , Proteínas Hedgehog/antagonistas & inibidores , Piridinas/química , Piridinas/farmacocinética , Administração Oral , Anilidas/administração & dosagem , Animais , Carvão Vegetal/farmacologia , Simulação por Computador , Cães , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Interações Medicamentosas , Hepatócitos/metabolismo , Humanos , Injeções Intravenosas , Absorção Intestinal , Masculino , Tamanho da Partícula , Piridinas/administração & dosagem , Solubilidade
16.
J Chromatogr Sci ; 40(7): 321-5, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12201475

RESUMO

Direct gas chromatographic (GC) analysis of thermally labile N-carbamates is studied by using fast GC with cold on-column injection. With the greatly reduced injection temperature, short column lengths, high flow rate, and fast temperature-programming rate, the exposure of carbamates to high temperature is reduced and degradation can be avoided. Nine N-carbamates in EPA Method 531 are eluted without thermal decomposition. The relative standard deviation percentage for peak areas average 1.9% for all of the carbamates analyzed. A conventional GC instrument is employed to simplify the experiments. GC-mass spectrometry is used to monitor the decomposition peaks.

17.
J Chromatogr Sci ; 40(6): 321-5, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12137203

RESUMO

Direct gas chromatographic (GC) analysis of thermally labile N-carbamates is studied by using fast GC with cold on-column injection. With the greatly reduced injection temperature, short column lengths, high flow rate, and fast temperature-programming rate, the exposure of carbamates to high temperature is reduced and degradation can be avoided. Nine N-carbamates in EPA Method 531 are eluted without thermal decomposition. The relative standard deviation percentage for peak areas average 1.9% for all of the carbamates analyzed. A conventional GC instrument is employed to simplify the experiments. GC-mass spectrometry is used to monitor the decomposition peaks.

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