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1.
J Acoust Soc Am ; 155(5): 2973-2989, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38717202

ABSTRACT

The detection probability of underwater weak targets using active sonar is low, and inter-pulse coherent integration can improve the signal-to-noise ratio of echoes. When a target executes a maneuvering turn, complex range and Doppler frequency migrations occur during the coherent integration time that decrease the coherent integration gain. Most existing integration methods simplify the target motion to a finite-order polynomial model but fail to integrate a maneuvering turning target (MTT) due to model mismatch. Hence, this study proposes an underwater MTT integration method based on the modified Radon-Fourier transform. The proposed method constructs a theoretically accurate motion model for the MTT and a phase compensation function to compensate for the Doppler frequency migration. Furthermore, it yields a well-focused integration peak in the range-velocity and offset angle-turn rate dimensions and accurately estimates the target motion parameters. Moreover, the proposed method is suitable for targets with radial and oblique uniform motions. The effectiveness of the proposed method is demonstrated through simulations and a lake test. The proposed method demonstrates good integration performance, with an integration gain approximately 4-7 dB higher than that of traditional methods when using 30 integration pulses.

2.
J Acoust Soc Am ; 154(5): 2843-2857, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37930179

ABSTRACT

Noncooperative maneuvering target motion analysis is one of the challenging tasks in the field of underwater target localization and tracking for passive sonar. Underwater noncooperative targets often perform various maneuvers, and the targets are commonly modeled as a combination of constant-velocity models and coordinate-turn models with unknown turning rates. Traditional algorithms for Doppler-bearing target motion analysis are incapable of processing noncooperative maneuvering targets because the algorithms rely on a priori information of the turning rate and the center frequency. To address these shortcomings, this paper proposes the joint estimated adaptive unscented Kalman filter (JE-AUKF) algorithm. The JE-AUKF places the center frequency and turning rate into the state vector and constructs a time-varying state model that self-adapts to a maneuvering target. The JE-AUKF also introduces a time-varying fading factor into the process noise covariance matrix to improve the tracking performance. Simulations and sea trials are conducted to compare the performance of the JE-AUKF with the iterative unscented Kalman filter, the interacting multiple model-unscented Kalman filter, the interacting multiple model-iterative unscented Kalman filter, and the interacting multiple model-joint estimated unscented Kalman filter. The result shows that the JE-AUKF achieves better tracking performance for noncooperative maneuvering targets.

3.
Clin Pharmacol Ther ; 114(5): 1134-1141, 2023 11.
Article in English | MEDLINE | ID: mdl-37669218

ABSTRACT

Oral extended-release (ER) dosage forms have been used to sustain blood drug levels, reduce adverse events, and improve patient compliance. We investigated potential effects of comedication on pharmacokinetic exposure of nifedipine ER products with different formulation designs and manufacturing processes. A clinical study compared a generic version of nifedipine ER tablet with pH-dependent dissolution behavior with an osmotic pump product with pH independent drug release under fasting condition. In this study, two nifedipine tablet products were tested with or without short-term omeprazole comedication in healthy subjects. Seven-day administration of omeprazole before nifedipine dosing significantly increased the gastric pH, and subsequently increased the geometric least square (LS) means of area under the concentration-time curve from time zero to the last measurable timepoint (AUC0-t ) and maximum plasma concentration (Cmax ) of nifedipine to 132.6% (90% confidence interval (CI): 120.6-145.7%) and 112.8% (90% CI: 100.8-126.3%) for pH-dependent ER tablets, and 120.6% (90% CI: 109.7-132.5%) and 122.5% (90% CI: 113.7-131.9%) for the pH-independent ER tablets, respectively. Similar extent of increase in AUC0-t and Cmax was confirmed in the subpopulations whose gastric pH was ≥ 4 or ≤ 3 in subjects with or without omeprazole administration. Given that similar increases in drug exposures were observed for both pH-dependent and pH-independent nifedipine formulations and the geometric LS mean ratios were between 112% and 133% with and without short-term omeprazole comedication, the gastric pH may have limited effects on omeprazole-induced nifedipine PK changes on the tested formulations. The inhibition of cytochrome P450 3A4 activity may play a significant role causing nifedipine exposure changes for both formulations, which would warrant additional assessment.


Subject(s)
Nifedipine , Omeprazole , Humans , Omeprazole/pharmacokinetics , Nifedipine/adverse effects , Nifedipine/pharmacokinetics , Healthy Volunteers , Biological Availability , Tablets , Area Under Curve , Cross-Over Studies , Administration, Oral
4.
J Acoust Soc Am ; 153(2): 1027, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36859115

ABSTRACT

Conventional double differential phase-shift keying modulation amplifies the phase noise and performs poorly under the time-varying direct-sequence spread-spectrum (DSSS) communication system. Therefore, the authors propose an iterative reception for DSSS communication in time-varying underwater acoustic channels. First, bit-interleaved coded modulation with iterative decoding integrated with multi-symbol differential detection is used. Second, this paper uses cross correlation method to estimate and track the Doppler shift of each symbol. Based on Doppler estimates, a dynamic linear prediction model is proposed to estimate and track the channel phase variation. Third, an algorithm for adaptive selection of reference signals is utilized to recover the magnitude attenuation of correlation peaks. Numerical simulation results demonstrate that the proposed reception achieves around 9 dB gain compared to conventional differential decision reception under constant acceleration of 0.14 m/s2. During the acoustic communication experiment in Songhua Lake, the proposed reception was tested by using a moving source at a speed of 1-6 knots at 2-m depth and the farthest distance between the transceivers is 2.8 km. The proposed reception achieves only one frame error from a total of 205 frames collected in the lake experiment, and it also achieves error-free communications over 96 frames during a 10 km depth deep-sea experiment.

5.
Int Ophthalmol ; 43(2): 411-422, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35947253

ABSTRACT

PURPOSE: To investigate the pterygium prevalence and evaluate risk factors of pterygium in rural type 2 diabetic (D2M) patients aged 50 years and above in Funing Country, Jiangsu Province, China. METHODS: A cross-sectional ophthalmic survey was conducted in type 2 diabetes mellitus (D2M) patients aged ≥ 50 years in Funing County, Jiangsu Province, China, which was named Jiangsu Diabetic Eye Disease Study (JDEDS). All participants underwent a comprehensive questionnaire and ocular examination. Pterygium was diagnosed by slit lamp examination. The risk factors associated with pterygium were evaluated with logistic regression models. RESULTS: The prevalence of pterygium was 22.37% (n = 427) and 95% confidence interval (CI) (20.50-24.24%) in D2M patients aged 50 years and above in JDEDS. The prevalence of pterygium was 18.32% (95% CI 15.33-21.32%) in men and 24.43% (95% CI 22.06-26.80%) in women. Women had a higher prevalence than men (p = 0.001). Multivariate analysis showed, for male participants with D2M, pterygium was independently associated with increasing age [70-79 years: OR and 95% CI 2.49(1.20-5.18), p = 0.014; ≥ 80 years: 4.84(2.04-11.47), p < 0.001], while cigarette smoking was the protective factors, especially in current smoker [OR and 95% CI 0.79(0.67-0.92); p = 0.003]. For female participants with D2M, age [60-69 years OR and 95% CI 1.68(1.07-2.62), p = 0.023; 70-79 years: 2.62(1.69-4.06), p < 0.001; ≥ 80 years:3.24(1.70-5.90), p < 0.001], hypertension [OR and 95% CI 1.40(1.05-1.87), p = 0.024], BMI 24-27.9 [OR and 95% CI 1.20(1.00-1.44), p = 0.047], higher HbA1c [(5.6-7.9) % OR and 95% CI 1.42(1.10-1.82), p = 0.006; (8.0-9.9) %: 1.32(1.10-1.58), p = 0.003] were risk factors. CONCLUSIONS: D2M patients aged over 50 years has a high prevalence of pterygium in JDEDS. The pterygium prevalence is higher in female D2M participants. Diabetes and related factors may be risk factors of pterygium in female D2M patients. Further studies are needed to explore the gender difference in the pathogenesis of pterygium in D2M subjects.


Subject(s)
Diabetes Complications , Diabetes Mellitus, Type 2 , Pterygium , Female , Humans , Male , Middle Aged , China/epidemiology , Cross-Sectional Studies , Diabetes Complications/complications , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , East Asian People , Prevalence , Pterygium/diagnosis , Pterygium/epidemiology , Pterygium/etiology , Risk Factors , Rural Population , Aged , Aged, 80 and over
6.
J Acoust Soc Am ; 151(5): 3426, 2022 May.
Article in English | MEDLINE | ID: mdl-35649933

ABSTRACT

Direction-of-arrival (DOA) estimation is widely used in underwater detection and localization. To address the high-resolution DOA estimation problem, a DenseBlock-based U-net structure is proposed in this paper. U-net is a U-shaped fully convolutional neural network, which yields a two-dimensional image. DenseBlock is a more efficient structure than typical convolutional layers. The proposed network replaces the concatenated convolutional layers in the original U-net with DenseBlocks. Through training, the network can remove the interference of sidelobes and noise in a conventional beam forming bearing-time record (BTR) and get a clean BTR; hence, this method has narrow beam width and few sidelobes. In addition, the network can be trained by simulation data and applied in actual data when the simulated and actual data are similar in BTR features, so the method has high generalization. For a multi-target problem, the network does not need to be trained on all cases with different target quantities and therefore can reduce the training set size. As a data-driven method, it does not rely on prior assumptions of the array model and possesses better robustness to array imperfections than typical model-based DOA algorithms. Simulations and experiments verify the advantages of the proposed method.

7.
Ann Transl Med ; 10(10): 547, 2022 May.
Article in English | MEDLINE | ID: mdl-35722410

ABSTRACT

Background: N6-methyladenosine (m6A) is found in almost all nuclear RNAs of eukaryotes, playing an important and diverse role in many biological processes. Nonetheless, the roles of m6A regulators in abdominal aortic aneurysm (AAA) unknown. Therefore, there is a pressing need to identify m6A RNA methylation regulators in the diagnosis of AAA, determination of individualized risk, discovery of therapeutic targets, and improve understanding of pathogenesis. Methods: The GSE98278 dataset were obtained from the Gene Expression Omnibus (GEO) database to perform differential analysis of m6A-related regulators between elective stable abdominal aortic aneurysms (eAAA) and abdominal aortic aneurysm ruptured (rAAA). The random forest model was used to screen candidate m6A regulators to predict the risk of rAAA. The single sample gene set enrichment analysis (ssGSEA) method was then used to evaluate the abundance of 23 immune cells in AAA. The m6A RNA Methylation Quantification Kit was used to measure the total m6A levels of AAA and normal abdominal aorta. The terminal deoxynucleotidyl transferase mediated dUTP Nick-End Labeling (TUNEL) apoptosis assay kit was used to detect the human aortic smooth muscle cells (HASMCs) apoptotic after RBM15 knockdown. Mechanically, RBM15 knockdown was found to reduce the expression of CASP3 in an m6A-dependent manner by Western blotting, RNA immunoprecipitation (RIP), and methylated RNA immunoprecipitation-quantitative polymerase chain reaction (MeRIP-RT-PCR). Results: RBM15, WTAP, ALKBH5, and IGFBP3 were highly expressed in rAAA. In contrast, RBM15B showed opposite results (P<0.05). The high m6A level in the rAAA compared with eAAA and normal abdominal aorta (P<0.05). The random forest model was used to screen 5 candidate m6A regulators to predict the risk of rAAA. Expression of the 5 m6A methylation regulators was validated in AAA samples (P<0.05). RBM15 knockdown inhibited the apoptosis of HASMCs. RBM15 knockdown reduced the expression of CASP3 in an m6A-dependent manner. A strong correlation between the five m6A methylation regulators and immune cell infiltration was identified. Conclusions: In summary, m6A regulators play nonnegligible roles in the occurrence of rAAA. Our investigation of m6A patterns may be able to guide future immunotherapy strategies for AAA.

8.
J Acoust Soc Am ; 150(2): 952, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34470307

ABSTRACT

Underwater platforms provide long-term detection of undersea targets. In this paper, we propose a method for the estimation of target motion parameters by submerged static acoustic detection equipment. The proposed method is based on the Radon transform of modeling the target moving in a uniform straight line. The heading angle, the time to the closest point of approach (CPA), and the ratio of velocity to the horizontal range of the target at the CPA to the sensor are obtained by applying the generalized Radon transform (GRT) to bearing-time records. The velocity of the target is determined by applying the GRT to the line-spectrum-time records. Furthermore, the motion trajectory of the target with respect to the detection equipment can be calculated from the above parameters. To validate the feasibility and performance of the proposed method, computer simulations and sea trials based on a fixed single vector measurement system were analyzed in this paper. The results suggest that the proposed method can accurately estimate the motion parameters and can calculate the trajectory of the moving vessel along a straight line at constant velocity.

9.
Pharm Res ; 38(7): 1263-1278, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34128146

ABSTRACT

A method to reproducibly mill abuse deterrent oxycodone hydrochloride (HCl) extended release (ER) tablets was developed for a nasal insufflation pharmacokinetic (PK) study. Several comminution methods were explored before determining that a conical mill resulted in controlled milling of tablets to a size range equal to or below 1000 µm. However, milling resulted in significant loss of oxycodone from abuse deterrent oxycodone HCl ER tablets compared to minimal oxycodone loss from oxycodone HCl immediate release (IR) tablets. Characterization of milled tablet powder showed that loss of oxycodone was not attributed to analytical procedures or oxycodone phase change during high intensity milling processes. The content uniformity of oxycodone in the milled tablet powder varied when ER and IR tablets were milled to a particle size distribution equal to or below 500 µm but did not vary when particles were sized above 500 µm to equal to or below 1000 µm. In addition, the initial excipient weight to drug substance weight ratio impacted the amount of oxycodone lost from the respective formulation. However, dissolution demonstrated that when oxycodone HCl ER tablets are milled, differences in excipient weight to drug substance weight ratio and particle size distribution of milled tablets did not result in significantly different release of oxycodone.


Subject(s)
Abuse-Deterrent Formulations , Analgesics, Opioid/chemistry , Drug Compounding/methods , Morphine Dependence/prevention & control , Oxycodone/chemistry , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/pharmacokinetics , Chemistry, Pharmaceutical , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/pharmacokinetics , Drug Liberation , Insufflation , Oxycodone/administration & dosage , Oxycodone/pharmacokinetics , Powders , Single Molecule Imaging , Tablets
10.
Clin Transl Sci ; 14(5): 1977-1987, 2021 09.
Article in English | MEDLINE | ID: mdl-33982418

ABSTRACT

This study assessed the impact of product particle sizes (fine: 106-500 µm; coarse: 500-1000 µm) on oxycodone pharmacokinetics (PK) following nasal insufflation of milled oxycodone extended-release (ER) abuse-deterrent (AD) tablets using immediate-release (IR) non-AD product as reference. Additionally, this study assessed the effects of different excipient to drug ratio (EDR) by comparing two products with fine particle size but different EDRs, again using IR non-AD as the control. Thirty milligrams of oxycodone were administered in each treatment. Coarsely milled 30 mg ER tablets demonstrated significantly lower maximum plasma concentration (Cmax ) and partial areas under the concentration-time curve (AUCs) than those of the finely milled IR tablets. Finely milled ER tablets demonstrated similar Cmax and partial AUCs but higher total systemic exposures than those of finely milled IR tablets. Finely milled 80 mg ER tablets were bioequivalent to IR tablet on all parameters. The finely milled 30 mg ER tablet was not bioequivalent to the coarsely milled 30 mg ER tablet and had higher values for all parameters. The finely milled 30 mg ER tablets (EDR 6.9) showed no PK differences with finely milled 80 mg ER tablets (EDR 4.9). No serious adverse events were reported. The study demonstrated a significant effect of particle sizes (106-1000 µm) on PK of milled and insufflated oxycodone ER AD tablets. EDR difference did not have any significant effects on the PK of finely milled oxycodone ER AD tablets. Particle size distribution should be considered when nasal AD properties of opioid drug products are investigated during drug development.


Subject(s)
Analgesics, Opioid/pharmacokinetics , Opioid-Related Disorders/etiology , Oxycodone/pharmacokinetics , Abuse-Deterrent Formulations , Administration, Intranasal , Adolescent , Adult , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/adverse effects , Area Under Curve , Cross-Over Studies , Delayed-Action Preparations/administration & dosage , Delayed-Action Preparations/adverse effects , Delayed-Action Preparations/pharmacokinetics , Female , Healthy Volunteers , Humans , Insufflation , Male , Middle Aged , Oxycodone/administration & dosage , Oxycodone/adverse effects , Particle Size , Tablets , Young Adult
11.
Mol Pharm ; 18(4): 1544-1557, 2021 04 05.
Article in English | MEDLINE | ID: mdl-33621099

ABSTRACT

Complex iron nanoparticle-based drugs are one of the oldest and most frequently administered classes of nanomedicines. In the US, there are seven FDA-approved iron nanoparticle reference drug products, of which one also has an approved generic drug product (i.e., sodium ferric gluconate (SFG)). These products are indicated for the treatment of iron deficiency anemia and are administered intravenously. On the molecular level, iron nanomedicines are colloids composed of an iron oxide core with a carbohydrate coating. This formulation makes nanomedicines more complex than conventional small molecule drugs. As such, these products are often referred to as nonbiological complex drugs (e.g., by the nonbiological complex drugs (NBCD) working group) or complex drug products (e.g., by the FDA). Herein, we report a comprehensive study of the physiochemical properties of the iron nanoparticle product SFG. SFG is the single drug for which both an innovator (Ferrlecit) and generic product are available in the US, allowing for comparative studies to be performed. Measurements focused on the iron core of SFG included optical spectroscopy, inductively coupled plasma mass spectrometry (ICP-MS), X-ray powder diffraction (XRPD), 57Fe Mössbauer spectroscopy, and X-ray absorbance spectroscopy (XAS). The analysis revealed similar ferric-iron-oxide structures. Measurements focused on the carbohydrate shell comprised of the gluconate ligands included forced acid degradation, dynamic light scattering (DLS), analytical ultracentrifugation (AUC), and gel permeation chromatography (GPC). Such analysis revealed differences in composition for the innovator versus the generic SFG. These studies have the potential to contribute to future quality assessment of iron complex products and will inform on a pharmacokinetic study of two therapeutically equivalent iron gluconate products.


Subject(s)
Drugs, Generic/chemistry , Ferric Compounds/chemistry , Nanoparticles/chemistry , Anemia, Iron-Deficiency/drug therapy , Chemistry, Pharmaceutical , Chromatography, Gel , Drugs, Generic/administration & dosage , Drugs, Generic/pharmacokinetics , Drugs, Generic/standards , Dynamic Light Scattering , Equivalence Trials as Topic , Ferric Compounds/administration & dosage , Ferric Compounds/pharmacokinetics , Ferric Compounds/standards , Humans , Nanoparticles/administration & dosage , Nanoparticles/standards , Quality Control , Ultracentrifugation
12.
Eur J Drug Metab Pharmacokinet ; 46(1): 41-51, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33064292

ABSTRACT

BACKGROUND AND OBJECTIVES: Proton pump inhibitors (PPIs) can affect the intragastric release of other drugs from their dosage forms by elevating the gastric pH. They may also influence drug absorption and metabolism by interacting with P-glycoprotein or with the cytochrome P450 (CYP) enzyme system. Nifedipine is a Biopharmaceutics Classification System (BCS) class II drug with low solubility across physiologic pH and high permeability. Previous studies have demonstrated that drug-drug interaction (DDI) existed between omeprazole and nifedipine with significantly increased systemic exposure of nifedipine in subjects after pre-treatment for 7 days with omeprazole compared to the subjects without omeprazole treatment. It was shown that omeprazole not only induced an increase in intragastric pH, but also inhibited the CYP3A4 activity, while CYP3A4-mediated oxidation is the main metabolic pathway of nifedipine. The purpose of this study is to apply a physiologically based pharmacokinetic (PBPK) modeling approach to investigate the DDI mechanism for an immediate release formulation of nifedipine with omeprazole. METHODS: A previously published model for omeprazole was modified to integrate metabolites and to update CYP inhibition based on the most updated published in vitro data. We simulated the nifedipine pharmacokinetics in healthy subjects with or without the multiple-dose pretreatment of omeprazole (20 mg) following oral administrations of immediate-release (IR) (10 mg) nifedipine. Nifedipine solubility at different pHs was used to simulate the nifedipine pharmacokinetics for both clinical arms. Multiple sensitivity analyses were performed to understand the impact of gastric pH and the CYP3A4-mediated gut and liver first pass metabolism on the overall nifedipine pharmacokinetics. RESULTS: The developed PBPK model properly described the pharmacokinetics of nifedipine and predicted the inhibitory effect of multiple-dose omeprazole on CYP3A4 activity. With the incorporation of the physiologic effect of omeprazole on both gastric pH and CYP3A4 to the PBPK model, the verified PBPK model allows evaluating the impact of the increase in gastric pH and/or CYP3A4 inhibition. The simulated results show that the nifedipine metabolic inhibition by omeprazole may play an important role in the DDI between nifedipine and omeprazole for IR nifedipine formulation. CONCLUSION: The developed full PBPK model with the capability to simulate DDI by considering gastric pH change and metabolic inhibition provides a mechanistic understanding of the observed DDI of nifedipine with a PPI, omeprazole.


Subject(s)
Cytochrome P-450 CYP3A Inhibitors/pharmacokinetics , Drug Interactions/physiology , Models, Biological , Nifedipine/pharmacokinetics , Omeprazole/pharmacokinetics , Proton Pump Inhibitors/pharmacokinetics , Calcium Channel Blockers/pharmacokinetics , Humans
13.
Vasa ; 50(2): 110-115, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32933402

ABSTRACT

Our meta-analysis focused on the relationship between homocysteine (Hcy) level and the incidence of aneurysms and looked at the relationship between smoking, hypertension and aneurysms. A systematic literature search of Pubmed, Web of Science, and Embase databases (up to March 31, 2020) resulted in the identification of 19 studies, including 2,629 aneurysm patients and 6,497 healthy participants. Combined analysis of the included studies showed that number of smoking, hypertension and hyperhomocysteinemia (HHcy) in aneurysm patients was higher than that in the control groups, and the total plasma Hcy level in aneurysm patients was also higher. These findings suggest that smoking, hypertension and HHcy may be risk factors for the development and progression of aneurysms. Although the heterogeneity of meta-analysis was significant, it was found that the heterogeneity might come from the difference between race and disease species through subgroup analysis. Large-scale randomized controlled studies of single species and single disease species are needed in the future to supplement the accuracy of the results.


Subject(s)
Aneurysm , Hyperhomocysteinemia , Hypertension , Homocysteine , Humans , Hyperhomocysteinemia/diagnosis , Hyperhomocysteinemia/epidemiology , Plasma
14.
AAPS PharmSciTech ; 21(2): 40, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-31897805

ABSTRACT

There is a need to develop in vitro dissolution methods that discriminate for particle size of the manipulated abuse deterrent formulation (ADF) and that can be used for in vivo predictive models since dissolution methods developed for intact formulation might not be suitable for manipulated ones. A vertical diffusion cell (VDC) and United States Pharmacopeia (USP) Apparatus 1, 2, and 4 were evaluated for measuring the dissolution of intact and manipulated metoprolol succinate tablets with abuse deterrent-like properties. These tablets were physically manipulated to produce fine (106-500 µm) and coarse (500-1000 µm) powder samples. The VDC method was not able to discriminate the effect of particle size on drug release with varied stirring rate (200 to 800 rpm), molecular weight cut-off (MWCO, 3-5 kDa to 12-14 kDa) of the diffusion membrane, or composition and ionic strength (0.45% and 0.9%) of receiver medium. Standard and modified USP Apparatus 1 and 2 methods were assessed; however, large variations (RSD > 20%) were observed with USP Apparatus 1 for manipulated product dissolution and floating powder samples caused failure of auto-sampling when using standard USP Apparatus 2. For the USP Apparatus 4 dissolution method, packing configuration (1, 3, 8 layers and blend), ionic strength of dissolution medium (0.017, 0.077, and 0.154 M additional NaCl), and flow rate (4, 8, 16 mL/min) were studied to discriminate the effect of particle size on release. The USP Apparatus 4 dissolution method was optimized by using a packaging configuration of 8 layers with 8 mL/min flow rate which exhibited low variability and complete drug release and it could be used for in vivo predictive models. The dissolution method variables can be optimized for a specific product for desirable reproducibility and discriminatory power when using USP Apparatus 4.


Subject(s)
Abuse-Deterrent Formulations , Drug Compounding/methods , Drug Liberation , Prescription Drug Misuse/prevention & control , Diffusion , Metoprolol/administration & dosage , Metoprolol/chemistry , Models, Theoretical , Molecular Weight , Particle Size , Powders , Solubility , Tablets
15.
Clin Pharmacol Ther ; 107(3): 650-661, 2020 03.
Article in English | MEDLINE | ID: mdl-31608434

ABSTRACT

Poor aqueous solubility and dissolution of drug candidates drive key decisions on lead series optimization during drug discovery, on formulation optimization, and clinical studies planning during drug development. The interpretation of the in vivo relevance of early pharmaceutical profiling is often confounded by the multiple factors affecting oral systemic exposure. There is growing evidence that in vitro drug solubility may underestimate the true in vivo solubility and lead to drug misclassification. Based on 10 poorly water-soluble tyrosine kinase inhibitors, this paper demonstrates the use of physiologically-based pharmacokinetic (PK) analysis in combination with early clinical PK data to identify drugs whose absorption is truly limited by solubility in vivo and, therefore, expected to exhibit food effect. Our study supports a totality of evidence approach using early clinical data to guide decisions on conducting drug interaction studies with food and acid-reducing agents.


Subject(s)
Food-Drug Interactions , Models, Biological , Protein Kinase Inhibitors/administration & dosage , Administration, Oral , Chemistry, Pharmaceutical/methods , Drug Development/methods , Humans , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacokinetics , Solubility , Water/chemistry
16.
J Acoust Soc Am ; 146(5): 3159, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31795695

ABSTRACT

A vector sensor can provide measurements of ocean acoustic fields in terms of the acoustic pressure and three-dimensional particle velocity, providing potentially highly-informative data for applications such as geoacoustic inversion. This paper applies nonlinear Bayesian inversion to vector sensor data to estimate seabed geoacoustic properties and uncertainties in South China Sea. Linear-frequency-modulated source transmissions, recorded as acoustic pressure and vertical particle velocity, are processed to estimate the vertical phase gradient of acoustic pressure at multiple frequencies as the inversion data. An advantage of this type of data is that it can be modeled without knowledge of the source spectrum, allowing inversion with an unknown source and a single sensor. Geoacoustic inversion of phase-gradient data is carried out and compared to inversion of the vertical acoustic impedance, another type of vector-sensor data, independent of the source spectrum, which has been considered previously. Model selection for the optimal number of seabed sediment layers is carried out using Bayesian information criterion, and parameter estimates, uncertainties, and correlations are calculated using delayed-rejection adaptive Metropolis-Hastings sampling. Results indicate a three-layer seabed model (including the semi-infinite basement), with properties in agreement with independent measurements including a high-resolution seismic profile and surficial sediment type from a core.

17.
J Acoust Soc Am ; 145(6): EL483, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31255152

ABSTRACT

The received low frequency signals in the long range shallow water will suffer severe attenuation and modal dispersion effect, which will distort the signal and deteriorate the communication performance. In this letter, a modal dispersion compensation receiver is proposed, which exploits the de-dispersion transform to compensate intra-mode dispersion and the rake combination to combine the multi-mode components. With the proposed receiver, the waveform expansion of high order modes is compensated, and thus more modes can be distinguished from the noise and the rake combination gain is improved, which leads to high communication accuracy. Simulation results show that the proposed receiver can achieve about 3 dB gain for the 40 km range and signal with a center frequency 400 Hz.

18.
Hepatol Int ; 13(3): 277-292, 2019 May.
Article in English | MEDLINE | ID: mdl-31069760

ABSTRACT

BACKGROUND: The aim of our study was to explore how C1QTNF1-AS1 regulated miR-221-3p/SOCS3 axis in human hepatocellular carcinoma (HCC). METHODS: Differentially expressed lncRNAs and genes were examined via RNA-seq. GO analysis and KEGG pathway enrichment analysis were carried out based on the function of dys-regulated mRNAs. RT-qPCR was employed to detect the relative mRNA expression level of C1QTNF1-AS1, miR-221-3p, SOCS3 and key genes in the JAK/STAT signaling pathway in HCC tissues and cells, and western blot analysis was conducted to detect the relative protein expression levels of SOCS3 and key proteins in the JAK/STAT signaling pathway in HCC tissues and cells. MTT assay, transwell assay and flow cytometry were utilized to assess HCC cell proliferation, invasion, migration and apoptosis. Dual luciferase reporter gene assay was used to verify the targeted relationship between C1QTNF1-AS1 and miR-221-3p, as well as between miR-221-3p and SOCS3. A tumorigenicity assay in nude mice was conducted to investigate the effects of C1QTNF1-AS1 on HCC tumor growth in vivo. RESULTS: C1QTNF1-AS1 and SOCS3 were down-regulated, while miR-221-3p was up-regulated in HCC tissues and cells. In HepG2 and Huh7 cells, overexpression of C1QTNF1-AS1 or SOCS3, as well as silence of miR-221-3p inhibited HCC cell proliferation, migration, and invasion and promoted HCC cell apoptosis. The results of the dual luciferase reporter gene assay indicated that miR-221-3p could directly target both C1QTNF1-AS1 and SOCS3. In addition, up-regulation of C1QTNF1-AS1 suppressed HCC tumor growth in vivo. CONCLUSION: Overexpression of C1QTNF1-AS1 down-regulated miR-221-3p and subsequently up-regulated SOCS3, thereby inhibiting HCC cell proliferation, migration and invasion and promoting apoptosis through the JAK/STAT signaling pathway.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression Regulation, Neoplastic , Liver Neoplasms/genetics , MicroRNAs/genetics , Proteins/genetics , RNA, Long Noncoding/metabolism , Suppressor of Cytokine Signaling 3 Protein/genetics , Animals , Cell Line, Tumor , Humans , Mice , Mice, Nude
19.
J Cell Physiol ; 234(11): 21049-21059, 2019 11.
Article in English | MEDLINE | ID: mdl-31016760

ABSTRACT

The potential usage of curcumin in diverse human diseases has been widely studied, including arteriosclerosis (AS). This study focused on investigating the relationship between curcumin and AS-associated microRNA, which may provide a better understanding of curcumin in a different mechanism. Human microvascular endothelial HMEC-1 cells were treated by curcumin alone or oxidized low-density lipoprotein (ox-LDL) plus curcumin, after which the following parameters were analyzed: cell viability, migration, and the expression of AS-associated factors. The regulatory effects of curcumin on miR-126 and signaling pathways involved in AS were then studied. Further, an animal model of AS was stimulated by feeding rabbits with 1% cholesterol diet. The effects of curcumin on the animal model were explored. We found that curcumin treatment significantly reduced HMEC-1 cells viability, migration, and the protein levels of MMP-2, MMP-9, and vascular endothelial growth factor (VEGF) in the presence or absence of ox-LDL. Meanwhile, the expression of VEGFR1 and VEGFR2 was repressed by curcumin. miR-126 was upregulated by curcumin. The abovementioned effects of curcumin on HMEC-1 cells were all attenuated when miR-126 was silenced. And also, VEGF was a target gene of miR-126, and curcumin could inhibit the activation of PI3K/AKT JAK2/STAT5 signaling pathways via miR-126. The effects of curcumin and its regulation on miR-126 and VEGF were confirmed in the animal model of AS. To sum up, curcumin exerted potent anti-AS property possibly via upregulating miR-126 and thereby inhibiting PI3K/AKT and JAK2/STAT5 signaling pathways.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Atherosclerosis/metabolism , Curcumin/pharmacology , Endothelial Cells/metabolism , MicroRNAs/metabolism , Animals , Cell Line , Cell Movement/drug effects , Cell Survival/drug effects , Endothelial Cells/drug effects , Humans , Rabbits , Signal Transduction/drug effects , Up-Regulation , Vascular Endothelial Growth Factor A/drug effects , Vascular Endothelial Growth Factor A/metabolism
20.
J Cell Physiol ; 234(11): 19921-19932, 2019 11.
Article in English | MEDLINE | ID: mdl-30982977

ABSTRACT

With the changing lifestyle, venous thrombosis (VT) is becoming increasingly prevalent and poses a burden on the health economy. Endothelial progenitor cells (EPCs) are recruited into resolving VT. We aimed to investigate the effect of plasminogen activator inhibitor 1 (PAI-1) silencing on the recanalization of VT in rat EPCs. EPCs and VT rat models were cultured and treated with negative control-siRNA vector and PAI-1-siRNA vector, respectively. 4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, wound-healing test, and Matrigel-induced tubular experiment were performed to detect the ability of cell proliferation, migration, and EPCs lumen formation. Immunohistochemistry was used to observe the recanalization of thrombus. The messenger RNA (mRNA) and protein expression of PAI-1 and vascular endothelial growth factor (VEGF) were determined by reverse transcription quantitative polymerase chain reaction and Western blot analysis. PAI-1-siRNA enhances the luminal formation ability of EPCs and significantly promotes EPCs homing. In response to PAI-1 gene silencing, tissues from inferior vena cava displayed reduced mRNA and protein expression of PAI-1, increased VEGF expression as well as promoted lumen-like structures. PAI-1 gene silencing can promote the recanalization of VT by enhancement of the luminal formation ability of rats' EPCs.


Subject(s)
Endothelial Progenitor Cells/metabolism , Gene Silencing , Plasminogen Activator Inhibitor 1/genetics , RNA, Small Interfering/metabolism , Venous Thrombosis/metabolism , AC133 Antigen/metabolism , Animals , Antigens, CD34/metabolism , Cell Movement , Cell Proliferation , Cells, Cultured , Neovascularization, Physiologic , Plasminogen Activator Inhibitor 1/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats, Sprague-Dawley , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism , Virus Assembly
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