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1.
Am J Hum Genet ; 109(12): 2185-2195, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36356581

RESUMEN

By combining data from 160,500 individuals with breast cancer and 226,196 controls of Asian and European ancestry, we conducted genome- and transcriptome-wide association studies of breast cancer. We identified 222 genetic risk loci and 137 genes that were associated with breast cancer risk at a p < 5.0 × 10-8 and a Bonferroni-corrected p < 4.6 × 10-6, respectively. Of them, 32 loci and 15 genes showed a significantly different association between ER-positive and ER-negative breast cancer after Bonferroni correction. Significant ancestral differences in risk variant allele frequencies and their association strengths with breast cancer risk were identified. Of the significant associations identified in this study, 17 loci and 14 genes are located 1Mb away from any of the previously reported breast cancer risk variants. Pathways analyses including 221 putative risk genes identified multiple signaling pathways that may play a significant role in the development of breast cancer. Our study provides a comprehensive understanding of and new biological insights into the genetics of this common malignancy.


Asunto(s)
Neoplasias de la Mama , Estudio de Asociación del Genoma Completo , Femenino , Humanos , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Transcriptoma/genética , Neoplasias de la Mama/genética , Estudios de Casos y Controles
2.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-37653437

RESUMEN

S-methyl-methionine (SMM), also known as vitamin U, is an important food supplement produced by various plants. In this study, we attempted to produce it in an engineered microorganism, Saccharomyces cerevisiae, by introducing an MMT gene encoding a methionine S-methyltransferase from Arabidopsis thaliana. The S. cerevisiae sake K6 strain, which is a Generally Recognized as Safe (GRAS) strain, was chosen as the host because it produces a significant amount of S-adenosylmethionine (SAM), a precursor of SMM. To increase SMM production in the host, MHT1 and SAM4 genes encoding homocysteine S-methyltransferase were knocked out to prevent SMM degradation. Additionally, MMP1, which encodes S-methyl-methionine permease, was deleted to prevent SMM from being imported into the cell. Finally, ACS2 gene encoding acetyl-CoA synthase was overexpressed, and MLS1 gene encoding malate synthase was deleted to increase SAM availability. Using the engineered strain, 1.92 g/L of SMM was produced by fed-batch fermentation. ONE-SENTENCE SUMMARY: Introducing a plant-derived MMT gene encoding methionine S-methyltransferase into engineered Saccharomyces cerevisiae sake K6 allowed microbial production of S-methyl-methionine (SMM).


Asunto(s)
Vitamina U , Saccharomyces cerevisiae/genética , Metionina , Racemetionina , S-Adenosilmetionina , Metiltransferasas
3.
Sensors (Basel) ; 22(23)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36502152

RESUMEN

Although hydraulic accumulators play a vital role in the hydraulic system, they face the challenges of being broken by continuous abnormal pulsating pressure which occurs due to the malfunction of hydraulic systems. Hence, this study develops anomaly detection algorithms to detect abnormalities of pulsating pressure for hydraulic accumulators. A digital pressure sensor was installed in a hydraulic accumulator to acquire the pulsating pressure data. Six anomaly detection algorithms were developed based on the acquired data. A threshold averaging algorithm over a period based on the averaged maximum/minimum thresholds detected anomalies 2.5 h before the hydraulic accumulator failure. In the support vector machine (SVM) and XGBoost model that distinguish normal and abnormal pulsating pressure data, the SVM model had an accuracy of 0.8571 on the test set and the XGBoost model had an accuracy of 0.8857. In a convolutional neural network (CNN) and CNN autoencoder model trained with normal and abnormal pulsating pressure images, the CNN model had an accuracy of 0.9714, and the CNN autoencoder model correctly detected the 8 abnormal images out of 11 abnormal images. The long short-term memory (LSTM) autoencoder model detected 36 abnormal data points in the test set.


Asunto(s)
Redes Neurales de la Computación , Máquina de Vectores de Soporte , Factores de Tiempo , Algoritmos
4.
J Cell Physiol ; 236(3): 1822-1839, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32716094

RESUMEN

Obesity is associated with an increase in adipose tissue, which is mediated by hyperplasia and hypertrophy. Therefore, inhibiting cell proliferation during mitotic clonal expansion (MCE) is one of the major strategies for preventing obesity. The antagonistic effects of Garcinia cambogia (G. cambogia) on obesity have been studied in animal experimental models. However, the effects of G. cambogia extract on MCE, and the underlying molecular mechanisms, are poorly understood. In this study, 3T3-L1 cells were used to investigate whether G. cambogia extract affected cell proliferation during MCE and to identify target molecules for any anti-adipogenic activity. G. cambogia extract suppressed isobutylmethylxanthine and dexamethasone-and-insulin (MDI)-induced adipogenesis at an early stage by attenuating MCE. In G. cambogia extract-treated preadipocytes, MDI-induced cell proliferation and cell cycle progression were inhibited by G0 /G1 arrest due to an increase in p21 and p27 expression, and inhibition of cyclin-dependent kinase 2, cyclin E1 expression, and retinoblastoma (Rb) phosphorylation. In addition, the MDI-induced phosphorylation and subsequent translocation into the nucleus of p90 ribosomal S6 kinase (p90RSK) and signal transducer and activator of transcription (Stat) 3 were suppressed. Specific inhibitors of p90RSK (FMK) and Stat3 (stattic) regulated cell proliferation and adipogenesis. In conclusion, this study demonstrated that G. cambogia extract inhibited MCE by regulating p90RSK, Stat3, and cell cycle proteins, leading to G0 /G1 arrest. These findings provide new insight into the mechanism by which G. cambogia suppresses adipocyte differentiation and show that p90RSK is critical for adipogenesis as a new molecular target.


Asunto(s)
Adipogénesis , Garcinia cambogia/química , Mitosis , Proteínas Quinasas S6 Ribosómicas 90-kDa/antagonistas & inhibidores , Factor de Transcripción STAT3/antagonistas & inhibidores , 1-Metil-3-Isobutilxantina/farmacología , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipogénesis/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Células Clonales , Dexametasona/farmacología , Insulina/farmacología , Ratones , Mitosis/efectos de los fármacos , Modelos Biológicos , Fosforilación/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Factor de Transcripción STAT3/metabolismo
5.
Molecules ; 26(4)2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33671835

RESUMEN

Sulfasalazine (SAS), an anti-inflammatory drug with potent cysteine/glutamate antiporter system xc-(SXC) inhibition has recently shown beneficial effects in brain-related diseases. Despite many reports related to central nervous system (CNS) effect of SAS, pharmacokinetics (PK) and metabolite identification studies in the brain for SAS were quite limited. The aim of this study was to investigate the pharmacokinetics and metabolite identification of SAS and their distributions in mouse brain. Using in vivo brain exposure studies (neuro PK), the PK parameters of SAS was calculated for plasma as well as brain following intravenous and oral administration at 10 mg/kg and 50 mg/kg in mouse, respectively. In addition, in vivo metabolite identification (MetID) studies of SAS in plasma and brain were also conducted. The concentration of SAS in brain was much lower than that in plasma and only 1.26% of SAS was detected in mouse brain when compared to the SAS concentration in plasma (brain to plasma ratio (%): 1.26). In the MetID study, sulfapyridine (SP), hydroxy-sulfapyridine (SP-OH), and N-acetyl sulfapyridine (Ac-SP) were identified in plasma, whereas only SP and Ac-SP were identified as significant metabolites in brain. As a conclusion, our results suggest that the metabolites of SAS such as SP and Ac-SP might be responsible for the pharmacological effect in brain, not the SAS itself.


Asunto(s)
Encéfalo/metabolismo , Sulfasalazina/análisis , Sulfasalazina/metabolismo , Animales , Masculino , Espectrometría de Masas , Ratones , Ratones Endogámicos ICR , Sulfasalazina/farmacocinética , Factores de Tiempo
6.
Biomed Chromatogr ; 34(8): e4855, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32304111

RESUMEN

MMAE is a potent antimitotic drug used as payload of an antibody-drug conjugate which shows potent activity in preclinical and clinical studies against a range of lymphomas, leukemia and solid tumors. Liquid chromatography-high resolution mass spectrometric method was developed for the quantification of MMAE and its preclinical pharmacokinetics. The method consisted of protein precipitation using acetonitrile (ACN) for sample preparation and liquid chromatography - quadrupole - time-of-flight - tandem mass spectrometry (LC-qTOF-MS/MS) analysis in the positive ion mode. A quadratic regression (weighted 1/concentration2 ), with an equation y = ax2 + bx + c, was used to fit calibration curves over the concentration range of 1.01-2,200 ng/mL for MMAE. The qualification run met the acceptance criteria of ±25% accuracy and precision values for QC samples. Recovery was 42.84%. The dilution integrity was determined for 5-fold dilution and the accuracy and precision ranged within ±25%. The stability results indicated that MMAE was stable for the following conditions: short-term (4 h), long-term (4 weeks), freeze/thaw (3 cycles) and post-preparative stability (12 h). This qualified method was successfully applied to a pharmacokinetic study of MMAE in rat as a preclinical animal model. The PK results suggest that MMAE has moderate CL and low BA.Also, these results would be helpful in having a comprehensive understanding of the PK characteristics of MMAE and developing ADC in future.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Oligopéptidos/sangre , Oligopéptidos/farmacocinética , Animales , Modelos Animales de Enfermedad , Inmunoconjugados , Modelos Lineales , Masculino , Oligopéptidos/administración & dosificación , Oligopéptidos/química , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Molecules ; 25(9)2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32397307

RESUMEN

5-Amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c) pyrimidine (SCH 58261) is one of the new chemical entities that has been developed as an adenosine A2A receptor antagonist. Although SCH 58261 has been reported to be beneficial, there is little information about SCH 58261 from a drug metabolism or pharmacokinetics perspective. This study describes the metabolism and pharmacokinetic properties of SCH 58261 in order to understand its behaviors in vivo. Rats were used as the in vivo model species. First, an LC-MS/MS method was developed for the determination of SCH 58261 in rat plasma. A GastroPlus™ simulation, in vitro microsomal metabolic stability, and bile duct-cannulated studies were also performed to understand its pharmacokinetic profile. The parameter sensitivity analysis of GastroPlus™ was used to examine the factors that influence exposure when the drug is orally administered. The factors are as follows: permeability, systemic clearance, renal clearance, and liver first-pass effect. In vitro microsomal metabolic stability indicates how much the drug is metabolized. The extrapolated hepatic clearance value of SCH 58261 was 39.97 mL/min/kg, indicating that the drug is greatly affected by hepatic metabolism. In vitro microsomal metabolite identification studies revealed that metabolites produce oxidized and ketone-formed metabolites via metabolic enzymes in the liver. The bile duct-cannulated rat study, after oral administration of SCH 58261, showed that a significant amount of the drug was excreted in feces. These results imply that the drug is not absorbed well in the body after oral administration. Taken together, SCH 58261 showed quite a low bioavailability when administered orally and this was likely due to significantly limited absorption, as well as high metabolism in vivo.


Asunto(s)
Antagonistas de Receptores Purinérgicos P1 , Pirimidinas , Espectrometría de Masas en Tándem , Triazoles , Animales , Disponibilidad Biológica , Cromatografía Liquida , Hígado/metabolismo , Masculino , Microsomas Hepáticos/metabolismo , Antagonistas de Receptores Purinérgicos P1/química , Antagonistas de Receptores Purinérgicos P1/farmacocinética , Antagonistas de Receptores Purinérgicos P1/farmacología , Pirimidinas/química , Pirimidinas/farmacocinética , Pirimidinas/farmacología , Ratas , Ratas Sprague-Dawley , Triazoles/química , Triazoles/farmacocinética , Triazoles/farmacología
8.
Molecules ; 25(7)2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32225092

RESUMEN

The novel prenyl transferase-mediated, site-specific, antibody-drug conjugate LCB14-0110 is comprised of a proprietary beta-glucuronide linker and a payload (Monomethyl auristatin F, MMAF, an inhibitor for tubulin polymerization) attached to human epidermal growth factor receptor 2 (HER2)-targeting trastuzumab. A LC-MS/MS method was developed to quantify the antibody-conjugated drug (acDrug) for in vitro linker stability and preclinical pharmacokinetic studies. The method consisted of affinity capture, enzymatic cleavage of acDrug, and LC-MS/MS analysis in the positive ion mode. A quadratic regression (weighted 1/concentration2), with the equation y = ax2 + bx + c, was used to fit calibration curves over the concentration range of 19.17~958.67 ng/mL for acDrug. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control (QC) samples. The overall recovery was 42.61%. The dilution integrity was for a series of 5-fold dilutions with accuracy and precision values ranging within ±25%. The stability results indicated that acDrug was stable at all stability test conditions (short-term: 1 day, long-term: 10 months, Freeze/Thaw (F/T): 3 cycles). This qualified method was successfully applied to in vitro linker stability and pharmacokinetic case studies of acDrug in rats.


Asunto(s)
Cromatografía Liquida , Inmunoconjugados/química , Inmunoconjugados/farmacocinética , Neopreno , Espectrometría de Masas en Tándem , Transferasas , Animales , Monitoreo de Drogas , Estabilidad de Medicamentos , Humanos , Estructura Molecular , Neopreno/química , Ratas , Transferasas/química , Trastuzumab/química , Trastuzumab/farmacocinética
9.
Molecules ; 25(5)2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32131453

RESUMEN

Parkinson's disease is one of the most common neurodegenerative diseases. Adenosine regulates the response to other neurotransmitters in the brain regions related to motor function. In the several subtypes of adenosine receptors, especially, adenosine 2A receptors (A2ARs) are involved in neurodegenerative conditions. ZM241385 is one of the selective non-xanthine A2AR antagonists with high affinity in the nanomolar range. This study describes the in vitro and in vivo pharmacokinetic properties of ZM241385 in rats. A liquid chromatography-quadrupole time-of-flight mass spectrometric (LC-qToF MS) method was developed for the determination of ZM241385 in rat plasma. In vivo IV administration studies showed that ZM241385 was rapidly eliminated in rats. However, the result of in vitro metabolic stability studies showed that ZM241385 had moderate clearance, suggesting that there is an extra clearance pathway in addition to hepatic clearance. In addition, in vivo PO administration studies demonstrated that ZM241385 had low exposure in rats. The results of semi-mass balance studies and the in silico PBPK modeling studies suggested that the low bioavailability of ZM241385 after oral administration in rats was due to the metabolism and by liver, kidney, and gut.


Asunto(s)
Antagonistas del Receptor de Adenosina A2 , Simulación por Computador , Triazinas , Triazoles , Antagonistas del Receptor de Adenosina A2/farmacocinética , Antagonistas del Receptor de Adenosina A2/farmacología , Animales , Masculino , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Ratas , Ratas Sprague-Dawley , Receptor de Adenosina A2A/metabolismo , Triazinas/farmacocinética , Triazinas/farmacología , Triazoles/farmacocinética , Triazoles/farmacología
10.
BMC Public Health ; 19(1): 267, 2019 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-30841877

RESUMEN

BACKGROUND: Cigarette smoking is a major health risk, particularly in male South Koreans. Smoking cessation can benefit health; however, the process of quitting smoking is difficult to some smokers and shows its relationship to their stress level. The hypothesis of this study is that who has failed attempts to stop smoking induce more stress than habitual smoking. METHODS: To test this, the analysis on the association between smoking cessation attempts and stress levels in smokers was performed. The Korean Community Health Survey (2011-2016) data with the total of 488,417 participants' data were used for this study. Survey data were analyzed using the chi-square test and logistic regression. As the dependent variable, self-reported level of stress was selected. RESULTS: Of the subject population, 78.3% (63.3% males, 81.4% females) felt stressed. Among participants who successfully stopped smoking, 73.0% (72.6% males, 78.1% females) reported feeling stressed. In contrast, of those who failed to stop smoking, 83.3% (83.6% males, 86.3% females) reported high stress levels. Among those who did not attempt smoking cessation, 81.1% (81.2% males, 80.3% females) responded that they experienced stress. Those who failed to stop smoking had higher odds of stress than those who did not attempt smoking cessation [odds ratio (OR) 1.11, 95% confidence interval (CI) 1.09-1.14, p < 0.001]. Those who successfully stopped smoking had lower odds of stress than those who did not attempt smoking cessation (OR 0.87, 95% CI 0.86-0.89, p < 0.001). CONCLUSION: The study found an association between unsuccessful smoking cessation and stress level. As the result, people who failed smoking cessation showed higher stress. These data should be considered in health policy recommendations for smokers.


Asunto(s)
Cese del Hábito de Fumar/psicología , Estrés Psicológico/epidemiología , Adulto , Fumar Cigarrillos/psicología , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , República de Corea/epidemiología , Adulto Joven
11.
Molecules ; 24(15)2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31362431

RESUMEN

A simple liquid chromatography-quadrupole-time-of-flight-mass spectrometric assay (LC-TOF-MS/MS) has been developed for the evaluation of metabolism and pharmacokinetic (PK) characteristics of monomethyl auristatin F (MMAF) in rat, which is being used as a payload for antibody-drug conjugates. LC-TOF-MS/MS method was qualified for the quantification of MMAF in rat plasma. The calibration curves were acceptable over the concentration range from 3.02 to 2200 ng/mL using quadratic regression. MMAF was stable in various conditions. There were no significant matrix effects between rat and other preclinical species. The PK studies showed that the bioavailability of MMAF was 0% with high clearance. Additionally, the metabolite profiling studies, in vitro/in vivo, were performed. Seven metabolites for MMAF were tentatively identified in liver microsome. The major metabolic pathway was demethylation, which was one of the metabolic pathways predicted by MedChem Designer. Therefore, these results will be helpful to understand the PK, catabolism, and metabolism behavior of MMAF comprehensively when developing antibody-drug conjugates (ADCs) in the future.


Asunto(s)
Cromatografía Liquida , Metabolómica , Oligopéptidos/farmacocinética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Animales , Biomarcadores , Cromatografía Liquida/métodos , Monitoreo de Drogas , Humanos , Masculino , Redes y Vías Metabólicas , Metabolómica/métodos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Oligopéptidos/química , Oligopéptidos/metabolismo , Ratas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
12.
Molecules ; 24(7)2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30987056

RESUMEN

Tozadenant is one of the selective adenosine A2a receptor antagonists with a potential to be a new Parkinson's disease (PD) therapeutic drug. In this study, a liquid chromatography-mass spectrometry based bioanalytical method was qualified and applied for the quantitative analysis of tozadenant in rat plasma. A good calibration curve was observed in the range from 1.01 to 2200 ng/mL for tozadenant using a quadratic regression. In vitro and preclinical in vivo pharmacokinetic (PK) properties of tozadenant were studied through the developed bioanalytical methods, and human PK profiles were predicted using physiologically based pharmacokinetic (PBPK) modeling based on these values. The PBPK model was initially optimized using in vitro and in vivo PK data obtained by intravenous administration at a dose of 1 mg/kg in rats. Other in vivo PK data in rats were used to validate the PBPK model. The human PK of tozadenant after oral administration at a dose of 240 mg was simulated by using an optimized and validated PBPK model. The predicted human PK parameters and profiles were similar to the observed clinical data. As a result, optimized PBPK model could reasonably predict the PK in human.


Asunto(s)
Benzotiazoles/sangre , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Antagonistas del Receptor de Adenosina A2 , Animales , Benzotiazoles/farmacocinética , Ratas , Verapamilo/sangre , Verapamilo/farmacocinética
13.
Environ Monit Assess ; 192(1): 66, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31879803

RESUMEN

The potential of diffusive gradient in thin film (DGT) as a long-term monitoring tool to assess trace level mercury (Hg) in surface waters was evaluated. A piston type DGT sampler and a plate-type device that could hold 15 DGTs were designed. The device contained piston type DGT samplers with varying diffusive gel thicknesses, that is, 0.5, 0.75, and 1.0 mm, respectively. Three DGT devices were deployed in a lake for 5 weeks, and two were deployed in a stream for 3 weeks. In the lake, the total Hg (THg) mass accumulated in the DGT varied between 0.05 and 0.15 ng, which increased with an increase in deployment time and decreased with an increase in agarose diffusion gel thickness. The DGT concentration in the lake water for a 2 week period was estimated to be about 0.8-1.0 ng/L, which was close to the measured value of 1.1 (± 0.13) ng/L, using the grab sampling technique. However, the DGT estimated at 4 and 6 weeks showed a concentration of about 0.5-0.7 ng/L, which is about twice as small as that measured by grab sampling. This underestimation of the THg levels in water appear to be caused by additional thicknesses of the physical diffusive boundary layer (0.15, 0.5, 1.29 mm) and biofilm, outside the DGT filter. The predicted DGT concentration in the upper stream of the Nakdong River was estimated to be about 0.8-1.4 ng/L, which is similar to the value of 1.22 (± 0.29) ng/L measured in the field by grab sampling. The concentration of THg was estimated to be about 1.0-1.2 ng/L, which is similar to the values measured by grab sampling. The additional diffusion thickness formed outside the DGT filter was 0.018 mm and 0.093 mm at 1 and 3 weeks, respectively, which is not larger than the diffusion gel thickness (0.5-1.0 mm). This was because DGT was installed in a region where the flow velocity is high, and the thickness of the diffusion boundary layer outside the filter is negligible.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Lagos/química , Mercurio/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Difusión , Diseño de Equipo , República de Corea
14.
Rapid Commun Mass Spectrom ; 32(11): 889-896, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29578307

RESUMEN

RATIONALE: The cassette-dosing technique is a technique that administers various drugs to a single animal at once and quantitated simultaneously. The purpose of this study was to evaluate the feasibility of cassette-dosing as a means of increasing throughput and decreasing animal usage for pharmacokinetic studies of biopharmaceuticals using liquid chromatography/time-of-flight mass spectrometric (LC/TOF-MS) analysis. METHODS: Brentuximab, trastuzumab, cetuximab and adalimumab were used as model biopharmaceuticals. The method consisted of immunoprecipitation followed by tryptic digestion for sample preparation and LC/TOF-MS analysis of specific signature peptides in the positive ion mode using electrospray ionization. The specific signature peptides used for quantification were from the complementarity-determining regions of each mAb. All rats received a single intravenous bolus injection containing either a single mAb or a mixture of four mAbs. RESULTS: The proposed method has been qualified in linearity range of 1-100 µg/mL with correlation coefficients higher than 0.990. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control (QC) samples. This qualified LC/TOF-MS method was successfully applied to a pharmacokinetic study in the rat. The PK properties of mAbs administered as a cassette-dosage were similar to the pharmacokinetics of each antibody drug when administered as a single entity. CONCLUSIONS: These findings suggest that the cassette-dosing approach could be used to evaluate the PK properties of biopharmaceuticals in the early drug discovery stage. Also, this method would be useful for other preclinical sample analysis without developing new reagents for sample preparation.


Asunto(s)
Anticuerpos Monoclonales Humanizados/sangre , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Adalimumab/administración & dosificación , Adalimumab/sangre , Animales , Anticuerpos Monoclonales Humanizados/administración & dosificación , Brentuximab Vedotina , Calibración , Cetuximab/administración & dosificación , Cetuximab/sangre , Inmunoconjugados/administración & dosificación , Inmunoconjugados/sangre , Límite de Detección , Ratones , Control de Calidad , Ratas Sprague-Dawley , Sensibilidad y Especificidad , Trastuzumab/administración & dosificación , Trastuzumab/sangre
15.
Eur J Cancer Care (Engl) ; 27(6): e12919, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30253019

RESUMEN

We investigated the symptom clusters and effects of symptom clusters on the quality of life of Korean breast cancer survivors. We recruited 241 breast cancer survivors and collected cross-sectional data on their symptoms. To determine inter-relationships among symptoms, a principal component analysis with varimax rotation was performed based on the patient's symptoms (fatigue, nausea/vomiting, pain, dyspnoea, insomnia, appetite loss, constipation, anxiety, depression, systemic therapy side effects, breast symptoms and arm symptoms). The first symptom cluster consisted of psychological (anxiety and depression) and general (appetite loss, fatigue, insomnia and dyspnoea) symptoms, whereas the second symptom cluster consisted of physical (arm symptom, breast symptom, pain and systemic therapy side effects) and gastrointestinal (nausea/vomiting and constipation) symptoms. Subgroup cluster analysis showed that breast cancer survivors with higher-scoring symptoms had significantly poorer quality of life in both psychological-general symptom cluster and physical-gastrointestinal symptom cluster subgroups, with subgroup-specific patterns. The symptom clusters differed depending on stage and functional status of breast cancer survivors. Breast cancer survivors may have a specific pattern of symptom clusters. Some symptom clusters may have a negative impact on the quality of life. Identifying symptom clusters of breast cancer survivors may have clinical implications by improving symptom management.


Asunto(s)
Neoplasias de la Mama/terapia , Supervivientes de Cáncer/estadística & datos numéricos , Calidad de Vida , Adulto , Anciano , Anorexia/epidemiología , Ansiedad/epidemiología , Ansiedad/psicología , Supervivientes de Cáncer/psicología , Análisis por Conglomerados , Estreñimiento/epidemiología , Estudios Transversales , Depresión/epidemiología , Depresión/psicología , Disnea/epidemiología , Fatiga/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Náusea/epidemiología , Dolor/epidemiología , Análisis de Componente Principal , República de Corea/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Síndrome , Centros de Atención Terciaria , Vómitos/epidemiología
16.
Biomed Chromatogr ; 32(7): e4229, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29505175

RESUMEN

A single hybrid affinity-captured-LC-TOF-MS/MS method was developed and applied for the quantification of total antibody, antibody conjugated drug and free payload of antibody drug conjugate (ADC). Adcetris®, a valine-citrulline monomethyl auristatin E conjugated ADC, was used as a model ADC compound. A quadratic regression (weighted 1/concentration) was used to fit calibration curves over the concentration range 30.65-613.00 ng/mL with an equation y = ax2 + bx + c for the antibody-conjugated drug of Adcetris®. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control samples. For the analysis of total antibody, a signature peptide (TTPPVLDSDGSFFLYSK, molecular weight 1874) was used after affinity capture using magnetic beads and on-bead trypsin digestion. A quadratic regression (weighted 1/concentration) was used to fit calibration curves over the concentration range 5.00-100.00 µg/mL with an equation y = ax2 + bx + c for total antibody. For free payload analysis of monomethyl auristatin E, a protein precipitation method followed by LC-TOF-MS/MS analysis was used. A quadratic regression (weighted 1/concentration) was used to fit calibration curves over the concentration range 1.01-2200 ng/mL with an equation y = ax2 + bx + c for free payload. Pharmacokinetic study samples and in vitro stability samples in rat were successfully analyzed by this a hybrid affinity-captured-LC-TOF-MS/MS method. This single platform method is a useful complementary method for the pharmacokinetics study of ADC with valine-citrulline linker at the early drug discovery stage.


Asunto(s)
Cromatografía Liquida/métodos , Inmunoconjugados/análisis , Inmunoconjugados/química , Espectrometría de Masas en Tándem/métodos , Animales , Brentuximab Vedotina , Estabilidad Proteica , Ratas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Biomed Chromatogr ; 32(3)2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28976575

RESUMEN

A liquid chromatographic-electrospray ionization-time-of-flight/mass spectrometric (LC-ESI-TOF/MS) method was developed and applied for the determination of WKYMVm peptide in rat plasma to support preclinical pharmacokinetics studies. The method consisted of micro-elution solid-phase extraction (SPE) for sample preparation and LC-ESI-TOF/MS in the positive ion mode for analysis. Phenanthroline (10 mg/mL) was added to rat blood immediately for plasma preparation followed by addition of trace amount of 2 m hydrogen chloride to plasma before SPE for stability of WKYMVm peptide. Then sample preparation using micro-elution SPE was performed with verapamil as an internal standard. A quadratic regression (weighted 1/concentration2 ), with the equation y = ax2 + bx + c was used to fit calibration curves over the concentration range of 3.02-2200 ng/mL for WKYMVm peptide. The quantification run met the acceptance criteria of ±25% accuracy and precision values. For quality control samples at 15, 165 and 1820 ng/mL from the quantification experiment, the within-run and the between-run accuracy ranged from 92.5 to 123.4% with precision values ≤15.1% for WKYMVm peptide from the nominal values. This novel LC-ESI-TOF/MS method was successfully applied to evaluate the pharmacokinetics of WKYMVm peptide in rat plasma.


Asunto(s)
Cromatografía Liquida/métodos , Oligopéptidos/sangre , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Animales , Modelos Lineales , Oligopéptidos/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
J Arthroplasty ; 33(8): 2512-2517, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29703678

RESUMEN

BACKGROUND: Patients with severe preoperative varus deformity have been reported to have high rates of loosening after total knee arthroplasty (TKA), primarily on the tibial side. This study investigated whether a short extension stem for the tibial component in severely varus knees would reduce the failure rate due to loosening on the tibial side. METHODS: Patients who underwent TKA, performed by a single surgeon using a single implant between November 1998 and January 2009, were retrospectively evaluated. Patients diagnosed with primary osteoarthritis, having a hip-knee-ankle axis greater than varus 8° on preoperative long-film radiographs, and postoperatively followed up for more than 2 years were included. Patients were divided into "stem" and "nonstem" groups, followed by 1:1 propensity score matching according to age, gender, body mass index, preoperative mechanical axis, and postoperative alignment. Tibial loosening rates in the 2 groups were compared. RESULTS: The study cohort included 602 patients, divided into "stem" and "nonstem" groups. Propensity score matching yielded 88 pairs of patients. Mean follow-up duration was similar in the stem and nonstem groups (109.22 vs 103.81 months, P = .451). None of the patients in the stem group, compared with 5 in the nonstem group, experienced aseptic loosening. The overall implant survival rate was significantly higher in the stem group than in the nonstem group (P = .0201). CONCLUSION: Using a short extension stem for the tibial component in primary TKA in patients with severe varus deformity greater than 8° may reduce the rate of loosening of the tibial side and increase the longevity of the implant. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Coxa Vara/complicaciones , Prótesis de la Rodilla/efectos adversos , Falla de Prótesis/etiología , Tibia/cirugía , Anciano , Índice de Masa Corporal , Femenino , Humanos , Rodilla/cirugía , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Osteoartritis/cirugía , Periodo Posoperatorio , Puntaje de Propensión , Diseño de Prótesis , Estudios Retrospectivos
19.
Sensors (Basel) ; 18(9)2018 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-30150577

RESUMEN

The emerging fog computing technology is characterized by an ultralow latency response, which benefits a massive number of time-sensitive services and applications in the Internet of things (IoT) era. To this end, the fog computing infrastructure must minimize latencies for both service delivery and execution phases. While the transmission latency significantly depends on external factors (e.g., channel bandwidth, communication resources, and interferences), the computation latency can be considered as an internal issue that the fog computing infrastructure could actively self-handle. From this view point, we propose a reinforcement learning approach that utilizes the evolution strategies for real-time task assignment among fog servers to minimize the total computation latency during a long-term period. Experimental results demonstrate that the proposed approach reduces the latency by approximately 16.1% compared to the existing methods. Additionally, the proposed learning algorithm has low computational complexity and an effectively parallel operation; therefore, it is especially appropriate to be implemented in modern heterogeneous computing platforms.

20.
Pharm Dev Technol ; 23(9): 857-864, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27881046

RESUMEN

Bee venom-loaded poly(lactic-co-glycolic acid) (PLGA) particles were prepared by double emulsion-solvent evaporation, and characterized for a sustained-release system. Factors such as the type of organic solvent, the amount of bee venom and PLGA, the type of PLGA, the type of polyvinyl alcohol, and the emulsification method were considered. Physicochemical properties, including the encapsulation efficiency, drug loading, particle size, zeta-potential and surface morphology were examined by Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The size of the bee venom-loaded PLGA particles was 500 nm (measured using sonication). Zeta-potentials of the bee venom-loaded PLGA particles were negative owing to the PLGA. FT-IR results demonstrated that the bee venom was completely encapsulated in the PLGA particles, indicated by the disappearance of the amine and amide peaks. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis indicated that the bee venom in the bee venom-loaded PLGA particles was intact. In vitro release of the bee venom from the bee venom-loaded PLGA particles showed a sustained-release profile over 1 month. Bee venom-loaded PLGA particles can help improve patients' quality of life by reducing the number of injections required.


Asunto(s)
Venenos de Abeja/síntesis química , Venenos de Abeja/farmacocinética , Portadores de Fármacos/síntesis química , Portadores de Fármacos/farmacocinética , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/síntesis química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacocinética , Venenos de Abeja/administración & dosificación , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/síntesis química , Preparaciones de Acción Retardada/farmacocinética , Portadores de Fármacos/administración & dosificación , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/administración & dosificación , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Difracción de Rayos X/métodos
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