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1.
Int J Mol Sci ; 24(18)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37762467

RESUMO

Nutritional imbalances have been associated with a higher risk for cognitive impairment. This study determined the red blood cell (RBC) fatty acid profile of newly diagnosed mild cognitive impairment (MCI) and Alzheimer's disease (AD) patients compared to age and gender-matched controls. There was a significant increase in palmitic acid (p < 0.00001) for both MCI and AD groups. Saturated fatty acids were significantly elevated in the MCI group, including stearic acid (p = 0.0001), arachidic acid (p = 0.003), behenic acid (p = 0.0002), tricosanoic acid (p = 0.007) and lignoceric acid (p = 0.001). n-6 polyunsaturated fatty acids (PUFAs) were significantly reduced in MCI, including linoleic acid (p = 0.001), γ-linolenic acid (p = 0.03), eicosatrienoic acid (p = 0.009) and arachidonic acid (p < 0.00004). The n-3 PUFAs, α-linolenic acid and docosahexaenoic acid, were both significantly reduced in MCI and AD (p = 0.0005 and p = 0.00003). A positive correlation was evident between the Mini-Mental State Examination score and nervonic acid in MCI (r = 0.54, p = 0.01) and a negative correlation with γ-linolenic acid in AD (r = -0.43, p = 0.05). Differences in fatty acid profiles may prove useful as potential biomarkers reflecting increased risk for dementia.

2.
BMC Genomics ; 23(1): 422, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668367

RESUMO

BACKGROUND: After an infection, human cells may contain viral genomes in the form of episomes or integrated DNA. Comparing the genomic sequences of different strains of a virus in human cells can often provide useful insights into its behaviour, activity and pathology, and may help develop methods for disease prevention and treatment. To support such comparative analyses, the viral genomes need to be accurately reconstructed from a large number of samples. Previous efforts either rely on customized experimental protocols or require high similarity between the sequenced genomes and a reference, both of which limit the general applicability of these approaches. In this study, we propose a pipeline, named ASPIRE, for reconstructing viral genomes accurately from short reads data of human samples, which are increasingly available from genome projects and personal genomics. ASPIRE contains a basic part that involves de novo assembly, tiling and gap filling, and additional components for iterative refinement, sequence corrections and wrapping. RESULTS: Evaluated by the alignment quality of sequencing reads to the reconstructed genomes, these additional components improve the assembly quality in general, and in some particular samples quite substantially, especially when the sequenced genome is significantly different from the reference. We use ASPIRE to reconstruct the genomes of Epstein Barr Virus (EBV) from the whole-genome sequencing data of 61 nasopharyngeal carcinoma (NPC) samples and provide these sequences as a resource for EBV research. CONCLUSIONS: ASPIRE improves the quality of the reconstructed EBV genomes in published studies and outperforms TRACESPipe in some samples considered.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Infecções por Vírus Epstein-Barr/genética , Genoma Viral , Genômica/métodos , Herpesvirus Humano 4/genética , Humanos , Filogenia , Análise de Sequência de DNA/métodos
3.
BMC Cancer ; 22(1): 1317, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36527000

RESUMO

BACKGROUND: Acquired chemo-drug resistance constantly led to the failure of chemotherapy for malignant cancers, consequently causing cancer relapse. Hence, identifying the biomarker of drug resistance is vital to improve the treatment efficacy in cancer. The clinical prognostic value of CYP24A1 remains inconclusive, hence we aim to evaluate the association between CYP24A1 and the drug resistance in cancer patients through a meta-analysis approach. METHOD: Relevant studies detecting the expression or SNP of CYP24A1 in cancer patients up till May 2022 were systematically searched in four common scientific databases including PubMed, EMBASE, Cochrane library and ISI Web of Science. The pooled hazard ratios (HRs) indicating the ratio of hazard rate of survival time between CYP24A1high population vs CYP24A1low population were calculated. The pooled HRs and odds ratios (ORs) with 95% confidence intervals (CIs) were used to explore the association between CYP24A1's expression or SNP with survival, metastasis, recurrence, and drug resistance in cancer patients. RESULT: Fifteen studies were included in the meta-analysis after an initial screening according to the inclusion and exclusion criteria. There was a total of 3784 patients pooled from all the included studies. Results indicated that higher expression or SNP of CYP24A1 was significantly correlated with shorter survival time with pooled HRs (95% CI) of 1.21 (1.12, 1.31), metastasis with pooled ORs (95% CI) of 1.81 (1.11, 2.96), recurrence with pooled ORs (95% CI) of 2.14 (1.45, 3.18) and drug resistance with pooled HRs (95% CI) of 1.42 (1.17, 1.68). In the subgroup analysis, cancer type, treatment, ethnicity, and detection approach for CYP24A1 did not affect the significance of the association between CYP24A1 expression and poor prognosis. CONCLUSION: Findings from our meta-analysis demonstrated that CYP24A1's expression or SNP was correlated with cancer progression and drug resistance. Therefore, CYP24A1 could be a potential molecular marker for cancer resistance.


Assuntos
Biomarcadores Tumorais , Neoplasias , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Resistência a Medicamentos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Prognóstico , Vitamina D3 24-Hidroxilase
4.
Nutr Cancer ; 74(9): 3058-3076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35675271

RESUMO

Plant extracts comprise a complex mixture of natural compounds with diverse biological activities including anticancer activities. This has made the use of plant extracts a trending strategy in cancer treatment. In addition, plants' active constituents such as polyphenols could confer protective effects on normal cells against damage by free radicals as well as lessen the toxicity of chemotherapeutic drugs. Recently, many emerging studies revealed the combinatory uses of plant extracts and individual therapeutic compounds that could be a promising panacea in hampering multiple signaling pathways involved in cancer development and progression. Besides enhancing the therapeutic efficacy, this has also been proven to reduce the dosage of chemotherapeutic drugs used, and hence overcome multiple drug resistance and minimize treatment side effects. Notably, combined use of plant extracts with chemotherapeutics drugs was shown to enhance anticancer effects through modulating various signaling pathways, such as P13K/AKT, NF-κB, JNK, ERK, WNT/ß-catenin, and many more. Hence, this review aims to comprehensively summarize both In Vitro and In Vivo mechanisms of actions of well-studied plant extracts, such as Ganoderma Lucidum, Korean red ginseng, Garcinia sp., curcumin, and luteolin extracts in augmenting anticancer properties of the conventional chemotherapeutic drugs from an extensive literature search of recent publications.


Assuntos
Curcumina , Neoplasias , Curcumina/uso terapêutico , Humanos , NF-kappa B , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Polifenóis/farmacologia , Polifenóis/uso terapêutico
5.
Rapid Commun Mass Spectrom ; 36(11): e9273, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35178789

RESUMO

RATIONALE: Systemic absorption of UV-filtering chemicals following topical application of sunscreens may present a safety concern. The Food and Drug Administration (FDA) had recommended an in vitro skin permeation test (IVPT) to evaluate the potential of this safety risk for the evaluation of sunscreens prior to clinical studies. Therefore, a sensitive and robust bioanalytical method(s) were required for IVPT studies of different topical sunscreen products. METHODS: An analytical procedure to quantitate sunscreen UV-filtering components and excipients in IVPT samples including avobenzone, octocrylene, oxybenzone, ecamsule, methylparaben and propylparaben was developed employing a RapidFire 360 robotic sample delivery system coupled with a triple quadrupole mass spectrometer. The analytical procedure was developed and validated according to the requirements of the FDA Bioanalytical Method Validation Guidance for Industry (2018). RESULTS: The analytical method provided a turnaround time of 12 seconds per sample and was determined to be accurate, precise, specific, and linear over the corresponding analytical ranges. The validated method was successfully applied for two IVPT studies for evaluating the skin permeation potential of UV-filtering chemicals and assisting with the selection of the sunscreen products for the clinical study conducted by the FDA. CONCLUSIONS: This work highlights the first analytical procedure that has applied a non-chromatographic-MS/MS automation platform to an in vitro biopharmaceutics study. The analytical platform simultaneously quantitated four UV filters and two excipients in complex media to evaluate their permeation in IVPT studies. The sample throughput and analytical performance of advanced automation platforms indicate their analytical procedure has the potential to significantly advance the efficiency of IVPT studies to evaluate permeation of a wide variety of UV chemical filters and excipients for topical OTC sunscreen products.


Assuntos
Absorção Cutânea , Protetores Solares , Automação , Excipientes , Humanos , Pele/química , Protetores Solares/análise , Espectrometria de Massas em Tandem/métodos
6.
PLoS Genet ; 15(4): e1008038, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30946743

RESUMO

Ankylosing spondylitis (AS) is a highly heritable immune-mediated arthritis common in Turkish and Iranian populations. Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disease most common in people of Mediterranean origin. MEFV, an FMF-associated gene, is also a candidate gene for AS. We aimed to identify AS susceptibility loci and also examine the association between MEFV and AS in Turkish and Iranian cohorts. We performed genome-wide association studies in 1001 Turkish AS patients and 1011 Turkish controls, and 479 Iranian AS patients and 830 Iranian controls. Serum IL-1ß, IL-17 and IL-23 cytokine levels were quantified in Turkish samples. An association of major effect was observed with a novel rare coding variant in MEFV in the Turkish cohort (rs61752717, M694V, OR = 5.3, P = 7.63×10(-12)), Iranian cohort (OR = 2.9, P = 0.042), and combined dataset (OR = 5.1, P = 1.65×10(-13)). 99.6% of Turkish AS cases, and 96% of those carrying MEFV rs61752717 variants, did not have FMF. In Turkish subjects, the association of rs61752717 was particularly strong in HLA-B27-negative cases (OR = 7.8, P = 8.93×10(-15)), but also positive in HLA-B27-positive cases (OR = 4.3, P = 7.69×10(-8)). Serum IL-1ß, IL-17 and IL-23 levels were higher in AS cases than controls. Among AS cases, serum IL-1ß and IL-23 levels were increased in MEFV 694V carriers compared with non-carriers. Our data suggest that FMF and AS have overlapping aetiopathogenic mechanisms. Functionally important MEFV mutations, such as M694V, lead to dysregulated inflammasome function and excessive IL-1ß function. As IL-1 inhibition is effective in FMF, AS cases carrying FMF-associated MEFV variants may benefit from such therapy.


Assuntos
Febre Familiar do Mediterrâneo/genética , Pirina/genética , Espondilite Anquilosante/genética , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Febre Familiar do Mediterrâneo/imunologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Antígeno HLA-B27/genética , Antígeno HLA-B51/genética , Humanos , Interleucina-1beta/sangue , Interleucina-23/sangue , Irã (Geográfico) , Masculino , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Espondilite Anquilosante/imunologia , Turquia
7.
Am Heart J ; 240: 101-113, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34175315

RESUMO

BACKGROUND: The presence and extent of left ventricular hypertrophy (LVH) is a major determinant of symptoms in patients with hypertrophic cardiomyopathy (HCM). There is increasing evidence to suggest that myocardial energetic impairment represents a central mechanism leading to LVH in HCM. There is currently a significant unmet need for disease-modifying therapy that regresses LVH in HCM patients. Perhexiline, a potent carnitine palmitoyl transferase-1 (CPT-1) inhibitor, improves myocardial energetics in HCM, and has the potential to reduce LVH in HCM. OBJECTIVE: The primary objective is to evaluate the effects of perhexiline treatment on the extent of LVH, in symptomatic HCM patients with at least moderate LVH. METHODS/DESIGN: RESOLVE-HCM is a prospective, multicenter double-blind placebo-controlled randomized trial enrolling symptomatic HCM patients with at least moderate LVH. Sixty patients will be randomized to receive either perhexiline or matching placebo. The primary endpoint is change in LVH, assessed utilizing cardiovascular magnetic resonance (CMR) imaging, after 12-months treatment with perhexiline. SUMMARY: RESOLVE-HCM will provide novel information on the utility of perhexiline in regression of LVH in symptomatic HCM patients. A positive result would lead to the design of a Phase 3 clinical trial addressing long-term effects of perhexiline on risk of heart failure and mortality in HCM patients.


Assuntos
Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/fisiopatologia , Fármacos Cardiovasculares/uso terapêutico , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Perexilina/uso terapêutico , Adulto , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Método Duplo-Cego , Ecocardiografia , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos
8.
Immunity ; 37(5): 880-92, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23159227

RESUMO

Overactivity of the germinal center (GC) pathway resulting from accumulation of follicular helper T (Tfh) cells causes autoimmunity, underscoring the need to understand the factors that control Tfh cell homeostasis. Here we have identifed posttranscriptional repression of interferon-γ (Ifng) mRNA as a mechanism to limit Tfh cell formation. By using the sanroque lupus model, we have shown that decreased Ifng mRNA decay caused excessive IFN-γ signaling in T cells and led to accumulation of Tfh cells, spontaneous GC, autoantibody formation, and nephritis. Unlike ICOS and T-bet deficiency that failed to rescue several autoimmune manifestations, interferon-γ receptor (IFN-γR) deficiency prevented lupus development. IFN-γ blockade reduced Tfh cells and autoantibodies, demonstrating that IFN-γ overproduction was required to sustain lupus-associated pathology. Increased IFN-γR signaling caused Bcl-6 overexpression in Tfh cells and their precursors. This link between IFN-γ and aberrant Tfh cell formation provides a rationale for IFN-γ blockade in lupus patients with an overactive Tfh cell-associated pathway.


Assuntos
Centro Germinativo/metabolismo , Interferon gama/genética , Interferon gama/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Autoanticorpos/imunologia , Autoimunidade/genética , Autoimunidade/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Feminino , Centro Germinativo/imunologia , Centro Germinativo/patologia , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Nefrite/genética , Nefrite/imunologia , Nefrite/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/imunologia , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Receptores de Interferon/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/patologia , Receptor de Interferon gama
9.
Clin Genet ; 97(5): 747-757, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32022900

RESUMO

FLNC-related myofibrillar myopathy could manifest as autosomal dominant late-onset slowly progressive proximal muscle weakness; involvements of cardiac and/or respiratory functions are common. We describe 34 patients in nine families of FLNC-related myofibrillar myopathy in Hong Kong ethnic Chinese diagnosed over the last 12 years, in whom the same pathogenic variant c.8129G>A (p.Trp2710*) was detected. Twenty-six patients were symptomatic when diagnosed; four patients died of pneumonia and/or respiratory failure. Abnormal amorphous material or granulofilamentous masses were detected in half of the cases, with mitochondrial abnormalities noted in two-thirds. We also show by haplotype analysis the founder effect associated with this Hong Kong variant, which might have occurred 42 to 71 generations ago or around Tang and Song dynasties, and underlain a higher incidence of myofibrillar myopathy among Hong Kong Chinese. The late-onset nature and slowly progressive course of the highly penetrant condition could have significant impact on the family members, and an early diagnosis could benefit the whole family. Considering another neighboring founder variant in FLNC in German patients, we advocate development of specific therapies such as chaperone-based or antisense oligonucleotide strategies for this particular type of myopathy.


Assuntos
Filaminas/genética , Músculo Esquelético/patologia , Miopatias Congênitas Estruturais/genética , Adulto , Idoso , Povo Asiático , Eletromiografia , Feminino , Efeito Fundador , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/diagnóstico por imagem , Debilidade Muscular/genética , Debilidade Muscular/patologia , Músculo Esquelético/diagnóstico por imagem , Mutação/genética , Miopatias Congênitas Estruturais/epidemiologia , Miopatias Congênitas Estruturais/patologia , Linhagem , Fenótipo
10.
Jpn J Clin Oncol ; 50(10): 1108-1116, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32579167

RESUMO

BACKGROUND: Patient-derived xenograft model is a powerful and promising tool for drug discovery and cancer biology studies. The application of previous metastatic colorectal cancer models has been greatly limited by its low success rate and long time to develop metastasis. Therefore, in this study, we aim to describe an optimized protocol for faster establishment of colorectal cancer metastatic patient-derived xenograft mouse models. METHODS: Smaller micro tissues (˂150 µm in diameter) mixed with Matrigel were engrafted subcutaneously into NSG mice to generate the passage 1 (P1) patient-derived xenograft. The micro tumours from P1 patient-derived xenograft were then excised and orthotopically xenografted into another batch of NSG mice to generate a metastatic colorectal cancer patient-derived xenograft, P2. Haematoxylin and eosin and immunohistochemistry staining were performed to compare the characters between patient-derived xenograft tumours and primary tumours. RESULTS: About 16 out of 18 P1 xenograft models successfully grew a tumour for 50.8 ± 5.1 days (success rate 89.9%). Six out of eight P1 xenograft models originating from metastatic patients successfully grew tumours in the colon and metastasized to liver or lung in the NSG recipients for 60.9 ± 4.5 days (success rate 75%). Histological examination of both P1 and P2 xenografts closely resembled the histological architecture of the original patients' tumours. Immunohistochemical analysis revealed similar biomarker expression levels, including CDH17, Ki-67, active ß-catenin, Ki-67 and α smooth muscle actin when compared with the original patients' tumours. The stromal components that support the growth of patient-derived xenograft tumours were of murine origin. CONCLUSIONS: Metastatic patient-derived xenograft mouse model could be established with shorter time and higher success rate. Although the patient-derived xenograft tumours were supported by the stromal cells of murine origin, they retained the dominant characters of the original patient tumours.


Assuntos
Neoplasias Colorretais/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Feminino , Xenoenxertos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica
11.
Pharmacoepidemiol Drug Saf ; 29(5): 575-581, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32134162

RESUMO

PURPOSE: In the late1990s, reacting to the outbreak of bovine spongiform encephalopathy (BSE) in the United Kingdom that caused a new variant of Creutzfeldt-Jakob disease (vCJD) in humans, manufacturers withdrew bovine heparin from the market in the United States. There have been growing concerns about the adequate supply and safety of porcine heparin. Since the BSE epidemic has been declining markedly, the US Food and Drug Administration reevaluates the vCJD risk via use of bovine heparin. METHODS: We developed a computational model to estimate the vCJD risk to patients receiving bovine heparin injections. The model incorporated information including BSE prevalence, infectivity levels in the intestines, manufacturing batch size, yield of heparin, reduction in infectivity by manufacturing process, and the dose-response relationship. RESULTS: The model estimates a median risk of vCJD infection from a single intravenous dose (10 000 USP units) of heparin made from US-sourced bovine intestines to be 6.9 × 10-9 (2.5-97.fifth percentile: 1.5 × 10-9 -4.3 × 10-8 ), a risk of 1 in 145 million, and 4.6 × 10-8 (2.5-97.fifth percentile: 1.1 × 10-8 -2.6 × 10-7 ), a risk of 1 in 22 million for Canada-sourced products. The model estimates a median risk of 1.4 × 10-7 (2.5-97.fifth percentile: 2.9 × 10-8 -9.3 × 10-7 ) and 9.6 × 10-7 (2.5-97.fifth percentile: 2.1 × 10-7 -5.6 × 10-6 ) for a typical treatment for venous thromboembolism (infusion of 2-4 doses daily per week) using US-sourced and Canada-sourced bovine heparin, respectively. CONCLUSIONS: The model estimates the vCJD risk from use of heparin when appropriately manufactured from US or Canadian cattle is likely small. The model and conclusions should not be applied to other medicinal products manufactured using bovine-derived materials.


Assuntos
Anticoagulantes/efeitos adversos , Síndrome de Creutzfeldt-Jakob/etiologia , Heparina/efeitos adversos , Animais , Bovinos , Aprovação de Drogas , Encefalopatia Espongiforme Bovina/epidemiologia , Humanos , Modelos Teóricos , Fatores de Risco , Reino Unido/epidemiologia , Estados Unidos , United States Food and Drug Administration
12.
Nucleic Acids Res ; 46(17): 8832-8847, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-29992318

RESUMO

Genomic sequencing of hepatocellular carcinoma (HCC) uncovers a paucity of actionable mutations, underscoring the necessity to exploit epigenetic vulnerabilities for therapeutics. In HCC, EZH2-mediated H3K27me3 represents a major oncogenic chromatin modification, but how it modulates the therapeutic vulnerability of signaling pathways remains unknown. Here, we show EZH2 acts antagonistically to AKT signaling in maintaining H3K27 methylome through epigenetic silencing of IGFBP4. ChIP-seq revealed enrichment of Ezh2/H3K27me3 at silenced loci in HBx-transgenic mouse-derived HCCs, including Igfbp4 whose down-regulation significantly correlated with EZH2 overexpression and poor survivals of HCC patients. Functional characterizations demonstrated potent growth- and invasion-suppressive functions of IGFBP4, which was associated with transcriptomic alterations leading to deregulation of multiple signaling pathways. Mechanistically, IGFBP4 stimulated AKT/EZH2 phosphorylation to abrogate H3K27me3-mediated silencing, forming a reciprocal feedback loop that suppressed core transcription factor networks (FOXA1/HNF1A/HNF4A/KLF9/NR1H4) for normal liver homeostasis. Consequently, the in vivo tumorigenicity of IGFBP4-silenced HCC cells was vulnerable to pharmacological inhibition of EZH2, but not AKT. Our study unveils chromatin regulation of a novel liver tumor suppressor IGFBP4, which constitutes an AKT-EZH2 reciprocal loop in driving H3K27me3-mediated epigenetic reprogramming. Defining the aberrant chromatin landscape of HCC sheds light into the mechanistic basis of effective EZH2-targeted inhibition.


Assuntos
Carcinogênese/genética , Carcinoma Hepatocelular/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Código das Histonas/genética , Histonas/metabolismo , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/deficiência , Neoplasias Hepáticas/genética , Proteínas Supressoras de Tumor/deficiência , Animais , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Feminino , Humanos , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Neoplasias Hepáticas Experimentais/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Terapia de Alvo Molecular , Prognóstico , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Neoplásico/genética , Análise de Sequência de RNA , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Anal Chem ; 91(22): 14170-14177, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31618017

RESUMO

Recent advances in high resolution mass spectrometry (MS) instrumentation and semi-automated software have led to a push toward the use of MS-based methods for quality control (QC) testing of therapeutic proteins in a cGMP environment. The approach that is most commonly being proposed for this purpose is known as the multi-attribute method (MAM). MAM is a promising approach that provides some distinct benefits compared to conventional methods currently used for QC testing of protein therapeutics, such as CEX, HILIC, and CE-SDS. Because MS-based methods have not been regularly used in this context in the past, new scientific and regulatory questions should be addressed prior to the final stages of implementation. We have categorized these questions into four major aspects for MAM implementation in a cGMP environment for both new and existing products: risk assessment, method validation, capabilities and specificities of the New Peak Detection (NPD) feature, and comparisons to conventional methods. This perspective outlines considerations for each of these main points and suggests approaches to help address potential issues.


Assuntos
Cromatografia Líquida/métodos , Eletroforese Capilar/métodos , Espectrometria de Massas/métodos , Peptídeos/análise , Proteínas/química , Animais , Anticorpos Monoclonais/química , Humanos , Controle de Qualidade
14.
Pharm Dev Technol ; 24(1): 105-117, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29336653

RESUMO

In this study, a novel three-compartmental population balance model (PBM) for a continuous twin screw wet granulation process is developed, combining the techniques of PBM and regression process modeling. The developed model links screw configuration, screw speed, and blend throughput with granule properties to predict the granule size distribution (GSD) and volume-average granule diameter. The granulator screw barrel was divided into three compartments along barrel length: wetting compartment, mixing compartment, and steady growth compartment. Different granulation mechanisms are assumed in each compartment. The proposed model therefore considers spatial heterogeneity, improving model prediction accuracy. An industrial data set containing 14 experiments is applied for model development. Three validation experiments show that the three-compartmental PBM can accurately predict granule diameter and size distribution at randomly selected operating conditions. Sixteen combinations of aggregation and breakage kernels are investigated in predicting the experimental GSD to best judge the granulation mechanism. The three-compartmental model is compared with a one-compartmental model in predicting granule diameter at different experimental conditions to demonstrate its advantage. The influence of the screw configuration, screw speed and blend throughput on the volume-average granule diameter is analyzed based on the developed model.


Assuntos
Química Farmacêutica/métodos , Modelos Teóricos , Tecnologia Farmacêutica/métodos , Tamanho da Partícula , Reprodutibilidade dos Testes
15.
AAPS PharmSciTech ; 20(3): 130, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30815748

RESUMO

For inhalation drug characterization, the traditionally used USP induction port provides limited in vivo predictive capability because it does not adequately mimic airway geometry. In this study, various bio-relevant mouth-throat (MT) models, including Alberta Idealized Throat (AIT), and 3D printed large/medium/small-sized VCU (Virginia Commonwealth University) models were evaluated using two metered dose inhaler (MDI) drug products: a solution MDI containing beclomethasone dipropionate (BDP-MDI) and a suspension MDI containing fluticasone propionate (FP-MDI). For BDP-MDI, use of VCU large and small MT models resulted in a significantly higher MT deposition and lower fine particle fraction (FPF) compared with the other MT models. In the case of FP-MDI, the three VCU models resulted in higher MT deposition and lower FPF compared with the USP induction port and AIT. Overall, the in vitro testing results for the suspension MDI were more sensitive to geometric differences of the MT models than those for the solution MDI. Our results suggest that in vitro characterization of MDI products can be influenced by many factors, including the type of formulation, the MT geometry, shape, internal space volume, and the material used to make the MT models.


Assuntos
Inaladores Dosimetrados , Modelos Anatômicos , Boca/anatomia & histologia , Faringe/anatomia & histologia , Administração por Inalação , Antiasmáticos/administração & dosagem , Antiasmáticos/química , Beclometasona/administração & dosagem , Beclometasona/química , Desenho de Equipamento , Fluticasona/administração & dosagem , Humanos , Tamanho da Partícula , Suspensões
16.
AAPS PharmSciTech ; 20(5): 209, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31161386

RESUMO

A tablet film coating and drying process was assessed by an experimentally validated thermodynamic balance model. Mass conservation equations were derived for the process air and the aqueous coating solution. Thermodynamic behavior of the solution was described by evaporation at the tablet surface and penetration into the tablet. Energy balance equations including heat loss to the atmosphere were coupled to the mass conservation equation. Experimental data using the ConsiGma™ coater (GEA, Belgium) were used for both parameter estimation and model validation. The results showed the proposed model can investigate primitive outlet variables and further internal variables representing evaporation and penetration. A sensitivity analysis revealed that evaporation depended more on the input parameters while penetration hinges on the tablet properties, particularly on the tablet volume affecting the tablet porosity.


Assuntos
Química Farmacêutica/métodos , Dessecação/métodos , Comprimidos com Revestimento Entérico/química , Cinética , Porosidade , Água/química
17.
Immunity ; 31(3): 457-68, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19631565

RESUMO

Follicular helper T (Tfh) cells provide selection signals to germinal center B cells, which is essential for long-lived antibody responses. High CXCR5 and low CCR7 expression facilitates their homing to B cell follicles and distinguishes them from T helper 1 (Th1), Th2, and Th17 cells. Here, we showed that Bcl-6 directs Tfh cell differentiation: Bcl-6-deficient T cells failed to develop into Tfh cells and could not sustain germinal center responses, whereas forced expression of Bcl-6 in CD4(+) T cells promoted expression of the hallmark Tfh cell molecules CXCR5, CXCR4, and PD-1. Bcl-6 bound to the promoters of the Th1 and Th17 cell transcriptional regulators T-bet and RORgammat and repressed IFN-gamma and IL-17 production. Bcl-6 also repressed expression of many microRNAs (miRNAs) predicted to control the Tfh cell signature, including miR-17-92, which repressed CXCR5 expression. Thus, Bcl-6 positively directs Tfh cell differentiation, through combined repression of miRNAs and transcription factors.


Assuntos
Linhagem da Célula , Proteínas de Ligação a DNA/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Citocinas/biossíntese , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Humanos , Camundongos , Camundongos Knockout , MicroRNAs/genética , Família Multigênica , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-6 , Linfócitos T Auxiliares-Indutores/citologia , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Regulação para Cima
18.
Intervirology ; 61(4): 193-203, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30541013

RESUMO

OBJECTIVE: Herpes simplex virus infection through the neuronal route is the most well-studied mode of viral encephalitis that can persists in a human host for a lifetime. However, the involvement of other possible infection mechanisms by the virus remains underexplored. Therefore, this study aims to determine the temporal effects and mechanisms by which the virus breaches the human brain micro-vascular endothelial cells of the blood-brain barrier. METHOD: An electrical cell-substrate impedance-sensing tool was utilized to study the real-time cell-cell barrier or morphological changes in response to the virus infection. RESULTS: Herpes simplex virus, regardless of type (i.e., 1 or 2), reduced the cell-cell barrier resistance almost immediately after virus addition to endothelial cells, with negligible involvement of cell-matrix adhesion changes. There is no exclusivity in the infection ability of endothelial cells. From 30 h after HSV infection, there was an increase in cell membrane capacitance with a subsequent loss of cell-matrix adhesion capability, indicating a viability loss of the infected endothelial cells. CONCLUSION: This study shows for the first time that destruction of human brain micro-vascular endothelial cells as an in vitro model of the blood-brain barrier could be an alternative invasion mechanism during herpes simplex virus infection.


Assuntos
Barreira Hematoencefálica/fisiologia , Barreira Hematoencefálica/virologia , Células Endoteliais/fisiologia , Células Endoteliais/virologia , Simplexvirus/crescimento & desenvolvimento , Sobrevivência Celular , Impedância Elétrica , Humanos , Modelos Biológicos
19.
J Pathol ; 238(5): 651-64, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26800240

RESUMO

Enhancer of zeste homolog 2 (EZH2) catalyses histone H3 lysine 27 trimethylation (H3K27me3) to silence tumour-suppressor genes in hepatocellular carcinoma (HCC) but the process of locus-specific recruitment remains elusive. Here we investigated the transcription factors involved and the molecular consequences in HCC development. The genome-wide distribution of H3K27me3 was determined by chromatin immunoprecipitation coupled with high-throughput sequencing or promoter array analyses in HCC cells from hepatitis B virus (HBV) X protein transgenic mouse and human cell models. Transcription factor binding site analysis was performed to identify EZH2-interacting transcription factors followed by functional characterization. Our cross-species integrative analysis revealed a crucial link between Yin Yang 1 (YY1) and EZH2-mediated H3K27me3 in HCC. Gene expression analysis of human HBV-associated HCC specimens demonstrated concordant overexpression of YY1 and EZH2, which correlated with poor survival of patients in advanced stages. The YY1 binding motif was significantly enriched in both in vivo and in vitro H3K27me3-occupied genes, including genes for 15 tumour-suppressive microRNAs. Knockdown of YY1 reduced not only global H3K27me3 levels, but also EZH2 and H3K27me3 promoter occupancy and DNA methylation, leading to the transcriptional up-regulation of microRNA-9 isoforms in HCC cells. Concurrent EZH2 knockdown and 5-aza-2'-deoxycytidine treatment synergistically increased the levels of microRNA-9, which reduced the expression and transcriptional activity of nuclear factor-κB (NF-κB). Functionally, YY1 promoted HCC tumourigenicity and inhibited apoptosis of HCC cells, at least partially through NF-κB activation. In conclusion, YY1 overexpression contributes to EZH2 recruitment for H3K27me3-mediated silencing of tumour-suppressive microRNAs, thereby activating NF-κB signalling in hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Inativação Gênica , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Apoptose , Sítios de Ligação , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA , Proteína Potenciadora do Homólogo 2 de Zeste , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Lisina , Metilação , Camundongos Nus , Camundongos Transgênicos , MicroRNAs/genética , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , Interferência de RNA , Transdução de Sinais , Fatores de Tempo , Transativadores/genética , Transativadores/metabolismo , Transfecção , Carga Tumoral , Regulação para Cima , Proteínas Virais Reguladoras e Acessórias , Fator de Transcrição YY1/genética
20.
AAPS PharmSciTech ; 18(5): 1585-1594, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27624069

RESUMO

The full-resolution next generation impactor (NGI) and three abbreviated impactor systems were used to obtain the apparent aerodynamic particle size distribution (APSD) and other quality measures for marketed dry powder inhalers (DPIs) using the compendial method and efficient data analysis (EDA). APSD for the active pharmaceutical ingredient (API) in Spiriva® Handihaler®, Foradil® Aerolizer®, and Relenza® Diskhaler® was obtained using a full-resolution NGI at 39, 60, and 90 L/min, respectively. Two reduced NGI (rNGI) configurations, the filter-only configuration (rNGI-f) and the modified-cup configuration (rNGI-mc), and the fast-screening impactor (FSI) with appropriate inserts to provide a 5-µm cut size were evaluated. The fine particle dose (FPD) obtained using the FSI for Spiriva was statistically similar to that obtained using the full NGI. However, the FPD for both Foradil and Relenza obtained using the FSI was significantly different from that obtained using the full NGI. Despite this, no significant differences were observed for the fine particle fraction (FPF) obtained using the FSI relative to that obtained from the full NGI for any of the DPIs. The use of abbreviated impactor systems appears promising with good agreement observed with the full-resolution NGI, except for small differences observed for the rNGI-mc configuration. These small differences may be product- and/or flow rate-specific, and further evaluation will be required to resolve these differences.


Assuntos
Aerossóis , Inaladores de Pó Seco/métodos , Fumarato de Formoterol , Brometo de Tiotrópio , Zanamivir , Administração por Inalação , Aerossóis/química , Aerossóis/farmacologia , Fumarato de Formoterol/administração & dosagem , Fumarato de Formoterol/química , Humanos , Teste de Materiais/métodos , Inaladores Dosimetrados , Tamanho da Partícula , Medicamentos para o Sistema Respiratório/administração & dosagem , Medicamentos para o Sistema Respiratório/química , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/métodos , Brometo de Tiotrópio/administração & dosagem , Brometo de Tiotrópio/química , Zanamivir/administração & dosagem , Zanamivir/química
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