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1.
Adv Ther ; 40(1): 349-366, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36348142

ABSTRACT

INTRODUCTION: Long-acting injectable antipsychotic agents have been suggested to improve adherence and patient outcomes in schizophrenia or schizoaffective disorder. The purpose of this study was to assess medication use patterns (i.e., medication adherence, persistence), hospital and emergency department readmissions, and total direct medical costs of Oklahoma Medicaid members with schizophrenia or schizoaffective disorder switching from an oral antipsychotic (OAP) to once-monthly paliperidone palmitate (PP1M) or to another OAP (OAP-switch). METHODS: A historical cohort analysis was conducted from 1 January 2016 to 31 December 2020 among adults aged ≥ 18 and ≤ 64 years with schizophrenia or schizoaffective disorder who were previously treated with an OAP. The first claim for PP1M or a new OAP defined the study index date. Members who transitioned from PP1M to 3-month formulation (PP3M) were included (i.e., PP1M/PP3M). Proportion of days covered (PDC), 45-day treatment gaps, 30-day readmissions to hospitals or emergency department, and total direct medical costs were assessed using multivariable, machine-learning least absolute shrinkage, and selection operator (Lasso) regressions controlling for numerous demographic, clinical, mental health, and provider characteristics. RESULTS: Among 295 Medicaid members meeting full inclusion criteria, 183 involved PP1M/PP3Ms (44 PP1M cases transitioned to PP3M) and 112 involved an OAP-switch. The multivariable-adjusted odds of readmission were significantly associated with a 45-day treatment gap (p < 0.05) and non-adherence (i.e., PDC < 80%) (p < 0.05). Relative to PP1M/PP3Ms, the multivariable analyses also indicated that OAP-switch was associated with an 18.5% lower PDC, 92.3% higher number of 45-day treatment gaps, and an approximately 90% higher odds of all-cause 30-day readmission (p < 0.05). The adjusted pre- to post-index change in cost was approximately 49% lower for OAP-switches versus PP1M/PP3Ms (p < 0.001), although unadjusted post-index costs did not differ between groups (p = 0.440). CONCLUSION: This real-world investigation of adult Medicaid members with schizophrenia or schizoaffective disorder observed improved adherence and persistence with fewer readmissions with PP1M/PP3Ms versus OAP-switches.


Subject(s)
Antipsychotic Agents , Psychotic Disorders , Schizophrenia , Adult , United States , Humans , Paliperidone Palmitate/therapeutic use , Antipsychotic Agents/therapeutic use , Schizophrenia/drug therapy , Patient Readmission , Retrospective Studies , Medicaid , Administration, Oral , Psychotic Disorders/drug therapy
2.
J Chromatogr A ; 1629: 461505, 2020 Oct 11.
Article in English | MEDLINE | ID: mdl-32861092

ABSTRACT

Immobilized metal affinity chromatography (IMAC) is a technique primarily used in research and development laboratories to purify proteins containing engineered histidine tags. Although this type of chromatography is commonly used, it can be problematic as differing combinations of resins and metal chelators can result in highly variable chromatographic performance and product quality results. To generate a robust IMAC purification process, the binding differences of resin and metal chelator combinations were studied by generating breakthrough curves with a poly-histidine tagged bispecific protein. The optimal binding combination was statistically analyzed to determine the impact of chromatographic parameters on the operation. Additionally, equilibrium uptake isotherms were created to further elucidate the impact of chromatographic parameters on the binding of protein. It was found that for protein expressed in CHO cells, Millipore Sigma's Fractogel EMD Chelate (M) charged with Zn2+ and GE's pre-charged Ni Sepharose Excel displayed the highest binding capacities. When the protein was expressed in HEK-293, GE's IMAC Sepharose 6 Fast Flow charged with either Co2+ or Zn2+ bound the greatest amount of protein. The study further identified the metal binding capacity of the resin lot, the protein capacity to which the resin is loaded, and the ratio of poly-histidine tag residues on the protein all impacted the chromatographic performance and product quality. These findings enabled the development of a robust and scalable process. The CHO expressed cell culture product was directly loaded at a high capacity onto variable metal binding affinity Fractogel EMD Chelate (M). A 250 mM imidazole elution condition ensured the product contained monomeric 4 and 6-histidine tagged bispecific proteins. The optimized IMAC process conditions determined in this study can be applied to a wide variety of poly-histidine tagged proteins in research and development laboratories as various poly-histidine tagged proteins of differing molecular weights and formats expressed in either HEK-293 or CHO cells were successfully purified.


Subject(s)
Chromatography, Affinity/methods , Histidine/metabolism , Metals/chemistry , Recombinant Proteins/isolation & purification , Animals , CHO Cells , Chelating Agents/chemistry , Chromatography, Reverse-Phase , Cobalt/chemistry , Cricetinae , Cricetulus , HEK293 Cells , Histidine/genetics , Humans , Recombinant Proteins/biosynthesis , Zinc/chemistry
3.
J Am Chem Soc ; 142(10): 4833-4841, 2020 Mar 11.
Article in English | MEDLINE | ID: mdl-32070102

ABSTRACT

Metal-organic frameworks are a class of porous compounds with potential applications in molecular sieving, gas sequestration, and catalysis. One family of MOFs, zeolitic imidizolate frameworks (ZIFs), is of particular interest for carbon dioxide sequestration. We have previously reported the heat capacity of the sodalite topology of the zinc 2-methylimidazolate framework (ZIF-8), and in this Article we present the first low-temperature heat capacity measurements of ZIF-8 with various amounts of sorbed CO2. Molar heat capacities from 1.8 to 300 K are presented for samples containing up to 0.99 mol of CO2 per mol of ZIF-8. Samples with at least 0.56 mol of CO2 per mol of ZIF-8 display a large, broad anomaly from 70 to 220 K with a shoulder on the low-temperature side, suggesting sorption-induced structural transitions. We attribute the broad anomaly partially to a gate-opening transition, with the remainder resulting from CO2 rearrangement and/or lattice expansion. The measurements also reveal a subtle anomaly from 0 to 70 K in all samples that does not exist in the sorbate-free material, which likely reflects new vibrational modes resulting from sorbate/ZIF-8 interactions. These results provide the first thermodynamic evidence of structural transitions induced by CO2 sorption in the ZIF-8 framework.

4.
Biotechnol Prog ; 36(1): e2921, 2020 01.
Article in English | MEDLINE | ID: mdl-31587529

ABSTRACT

Viral contamination is an inherent risk during the manufacture of biopharmaceuticals. As such, biopharmaceutical companies must demonstrate the viral clearance efficacy of their downstream process steps prior to clinical trials and commercial approval. This is accomplished through expensive and logistically challenging spiking studies, which utilize live mammalian viruses. These hurdles deter companies from analyzing viral clearance during process development and characterization. We utilized a noninfectious minute virus of mice-mock virus particle (MVM-MVP) as a surrogate spiking agent during small scale viral filtration (VF) and anion exchange chromatography (AEX) studies. For VF experiments, in-process mAb material was spiked and processed through Asahi Kasei P15, P20, P35, and BioEX nanofilters. Across each filter type, flux decay profiles and log reduction values (LRVs) were nearly identical for either particle. For AEX experiments, loads were conditioned with various amounts of sodium chloride (9, 20, 23, and 41 mS/cm), spiked with either particle and processed through a Q-SFF packed column. LRV results met our expectations of predicting MVM removal.


Subject(s)
Chromatography, Ion Exchange , Filtration , Minute Virus of Mice/isolation & purification , Anions , Minute Virus of Mice/chemistry , Sodium Chloride/chemistry , Virion/chemistry
5.
Int J Pharm ; 565: 162-173, 2019 Jun 30.
Article in English | MEDLINE | ID: mdl-31054877

ABSTRACT

Determining the stability of downstream process (DSP) intermediates is an extremely important parameter used to maintain product quality attributes within their acceptance ranges. The IgG4 monoclonal antibody studied (mAb1) showed aggregation under acidic conditions, inhibiting the use of low pH treatment to inactivate endogenous retroviruses, and poor virus filtration performance. Both manufacturing steps are included in mAb DSP for viral clearance. The impact of several new compounds on the aggregation and stabilization of mAb1 in process intermediate pools encountered during these critical DSP steps was investigated. Results showed that, in the presence of a protein stabilizer at pH 3.2, 27% less aggregation was observed compared to controls, during the low pH treatment for viral inactivation. The impact of a novel protein stabilizer on virus filter throughput during mAb1 filtration was compared to L-arginine using an innovative high-throughput automation technique. Compared to control experiments without additives, conditions were found where a 70% increase in filter volumetric throughput was achieved in the presence of the novel stabilizer, and a 56% decrease in volumetric throughput observed with L-arginine. These findings present the possibility of using these novel compounds to stabilize proteins during DSP and permitting the use of platform DSP elements such as low pH treatment and high-throughput virus filtration to challenging and unstable proteins.


Subject(s)
Antibodies, Monoclonal/chemistry , Immunoglobulin G/chemistry , Chemistry, Pharmaceutical , Drug Stability , Filtration , Hydrogen-Ion Concentration , Viruses
6.
Biologicals ; 58: 28-34, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30661901

ABSTRACT

Virus removal by ion exchange chromatography enhances the safety profile of therapeutic protein products. The robustness of virus removal depends on electrostatic binding between virus and oppositely charged chromatography media. However, model retrovirus Xenotropic Murine Leukemia Virus (XMuLV) binding remains robust even when virus and media are both positively charged. We investigated this counter-intuitive phenomenon using side-by-side comparison of virus-media binding behavior of XMuLV versus parvovirus, two viruses very different in size and structure but comparable in isoelectric point. When both viruses were negatively charged, XMuLV bound to positive anion exchange media with higher strength than parvovirus. When both viruses were positively charged, XMuLV remained tightly bound to positive media but parvovirus was dissociated. Likewise, XMuLV binding to media was much stronger than parvovirus under cation exchange conditions. These findings suggest that XMuLV binding could be enhanced by localized charge distribution not possessed by parvovirus, which is an important consideration for designing chromatography processes with robust virus removal capacity.


Subject(s)
Virus Inactivation , Viruses , Animals , CHO Cells , Chromatography, Ion Exchange/methods , Cricetinae , Cricetulus
7.
Genes Dev ; 31(17): 1770-1783, 2017 09 01.
Article in English | MEDLINE | ID: mdl-28982760

ABSTRACT

Direct reprogramming of fibroblasts to cardiomyocytes represents a potential means of restoring cardiac function following myocardial injury. AKT1 in the presence of four cardiogenic transcription factors, GATA4, HAND2, MEF2C, and TBX5 (AGHMT), efficiently induces the cardiac gene program in mouse embryonic fibroblasts but not adult fibroblasts. To identify additional regulators of adult cardiac reprogramming, we performed an unbiased screen of transcription factors and cytokines for those that might enhance or suppress the cardiogenic activity of AGHMT in adult mouse fibroblasts. Among a collection of inducers and repressors of cardiac reprogramming, we discovered that the zinc finger transcription factor 281 (ZNF281) potently stimulates cardiac reprogramming by genome-wide association with GATA4 on cardiac enhancers. Concomitantly, ZNF281 suppresses expression of genes associated with inflammatory signaling, suggesting the antagonistic convergence of cardiac and inflammatory transcriptional programs. Consistent with an inhibitory influence of inflammatory pathways on cardiac reprogramming, blockade of these pathways with anti-inflammatory drugs or components of the nucleosome remodeling deacetylase (NuRD) complex, which associate with ZNF281, stimulates cardiac gene expression. We conclude that ZNF281 acts at a nexus of cardiac and inflammatory gene programs, which exert opposing influences on fibroblast to cardiac reprogramming.


Subject(s)
Cellular Reprogramming/genetics , Gene Expression Regulation/genetics , Transcription Factors/metabolism , Anti-Inflammatory Agents/pharmacology , Cellular Reprogramming/drug effects , Fibroblasts/physiology , GATA4 Transcription Factor/metabolism , Gene Expression Regulation/drug effects , Genome-Wide Association Study , Mi-2 Nucleosome Remodeling and Deacetylase Complex/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/physiology , Repressor Proteins , Transcriptome
8.
Biotechnol Prog ; 33(1): 140-145, 2017 01.
Article in English | MEDLINE | ID: mdl-27798957

ABSTRACT

Recombinant therapeutic monoclonal antibodies (mAbs) must be purified from host cell proteins (HCPs), DNA, and other impurities present in Chinese hamster ovary (CHO) cell culture media. HCPs can potentially result in adverse clinical responses in patients and, in specific cases, have caused degradation of the final mAb product. As reported previously, residual traces of cathepsin D caused particle formation in the final product of mAb-1. The current work was focused on identification of a primary sequence in mAb-1 responsible for the binding and consequent co-purification of trace levels of CHO cathepsin D. Surface plasmon resonance (SPR) was used to detect binding between immobilized CHO cathepsin D and a panel of mAbs. Out of 13 mAbs tested, only mAb-1 and mAb-6 bound to cathepsin D. An LYY motif in the HC CDR2 was common, yet unique, to only these two mAbs. Mutation of LYY to AAA eliminated binding of mAb-1 to cathepsin D providing confirmation that this sequence motif was involved in the binding to CHO cathepsin D. Interestingly, the binding between mAb-1 and cathepsin D was weaker than that of mAb-6, which may be related to the fact that two aspartic acid residues near the LYY motif in mAb-1 are replaced with neutral serine residues in mAb-6. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:140-145, 2017.


Subject(s)
Antibodies, Monoclonal/isolation & purification , Cathepsin D/isolation & purification , Culture Media/chemistry , Immunoglobulin G/isolation & purification , Recombinant Proteins/isolation & purification , Animals , Antibodies, Monoclonal/chemistry , CHO Cells , Cathepsin D/chemistry , Cathepsin D/genetics , Cricetulus , Immobilized Proteins/chemistry , Immunoglobulin G/chemistry , Immunoglobulin G/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/genetics
9.
Int J Cardiovasc Imaging ; 32(7): 1121-30, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27076226

ABSTRACT

Right-sided heart failure is the most common cause of death in pulmonary hypertension (PH). Echocardiographic measurements of right atrial (RA) size are associated with worse outcome in PH, however the association between RA function and death in PH has not been well-described. 160 PH patients (World Health Organization groups 1-5) underwent cardiac magnetic resonance imaging (cMRI) and right heart catheterization (RHC) within 6 weeks of each other at a tertiary care academic medical center in the United States. We measured cMRI RA maximum and minimum volumes indexed to body surface area and calculated RA emptying fraction (RAEF). We evaluated the relationship between RAEF and clinical variables with death using Cox proportional hazard models. 57 deaths occurred during a median follow-up of 3.5 years (36 % died overall, 10 % per year). RAEF was directly correlated in univariate analyses with right ventricular (RV) ejection fraction, left ventricular (LV) ejection fraction, LV size, cardiac index, absence of tricuspid and pulmonic regurgitation, absence of pericardial effusion, estimated glomerular filtration rate, 6-minute walk distance, and pulmonary arterial oxygen saturation, whereas it was inversely correlated with death, BNP, heart rate, mean RA pressure, mean PA pressure, pulmonary and systemic vascular resistance, RV size, and RA size. Using multivariate analyses, RAEF had a robust inverse association with death after adjusting for measured risk factors (HR per 5 % change in RAEF: 0.83 [95 % CI 0.73-0.94], p = 0.003). In PH patients, decreased RAEF by cMRI is independently associated with worse survival after adjustment for other risk factors.


Subject(s)
Atrial Function, Right , Heart Failure/mortality , Hypertension, Pulmonary/mortality , Adult , Aged , Cardiac Catheterization , Cause of Death , Female , Heart Failure/diagnosis , Heart Failure/physiopathology , Humans , Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/physiopathology , Kaplan-Meier Estimate , Magnetic Resonance Imaging, Cine , Male , Middle Aged , Multivariate Analysis , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Retrospective Studies , Risk Factors , Stroke Volume , Tertiary Care Centers , Texas , Time Factors , Ventricular Function, Left , Ventricular Function, Right
10.
Proc Natl Acad Sci U S A ; 112(38): 11864-9, 2015 Sep 22.
Article in English | MEDLINE | ID: mdl-26354121

ABSTRACT

Conversion of fibroblasts to functional cardiomyocytes represents a potential approach for restoring cardiac function after myocardial injury, but the technique thus far has been slow and inefficient. To improve the efficiency of reprogramming fibroblasts to cardiac-like myocytes (iCMs) by cardiac transcription factors [Gata4, Hand2, Mef2c, and Tbx5 (GHMT)], we screened 192 protein kinases and discovered that Akt/protein kinase B dramatically accelerates and amplifies this process in three different types of fibroblasts (mouse embryo, adult cardiac, and tail tip). Approximately 50% of reprogrammed mouse embryo fibroblasts displayed spontaneous beating after 3 wk of induction by Akt plus GHMT. Furthermore, addition of Akt1 to GHMT evoked a more mature cardiac phenotype for iCMs, as seen by enhanced polynucleation, cellular hypertrophy, gene expression, and metabolic reprogramming. Insulin-like growth factor 1 (IGF1) and phosphoinositol 3-kinase (PI3K) acted upstream of Akt whereas the mitochondrial target of rapamycin complex 1 (mTORC1) and forkhead box o3 (Foxo3a) acted downstream of Akt to influence fibroblast-to-cardiomyocyte reprogramming. These findings provide insights into the molecular basis of cardiac reprogramming and represent an important step toward further application of this technique.


Subject(s)
Cellular Reprogramming , Fibroblasts/metabolism , Myocytes, Cardiac/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Transcription, Genetic , Animals , Calcium/metabolism , Calcium Signaling , Cell Differentiation , Embryo, Mammalian/cytology , Fibroblasts/cytology , Mice , Myocardial Contraction , Myocytes, Cardiac/cytology , Sequence Analysis, RNA , Time Factors , Transcription Factors/metabolism
11.
Hypertension ; 56(5): 981-7, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20823378

ABSTRACT

Genetic and functional data support a role for angiotensinogen in blood pressure control, and many population studies have suggested that polymorphisms in the angiotensinogen gene contribute to hypertension. Two common haplotypes of the human angiotensinogen gene are -6A/235T and -6G/235M. To study their contributions to blood pressure regulation in a controlled model system, we developed triple-transgenic mice expressing either -6A/235T or -6G/235M human angiotensinogen, expressing either an overexpressed and poorly regulated (REN9) or a tightly regulated (PAC160) human renin, and all carrying a null mutation in the endogenous murine angiotensinogen gene. These humanized mice were then examined for blood pressure differences at baseline and after a high-salt diet, changes in cardiovascular organ weight, and differences in angiotensinogen and renin gene expression. Mice expressing the -6G/235M haplotype on the PAC160 background exhibited increased blood pressure and cardiac hypertrophy at baseline. In contrast, all of the mice with the REN9 background had equivalent baseline blood pressures. On the REN9 background, there was a greater increase in blood pressure in -6A/235T in response to a high-salt diet, providing evidence it may be a susceptibility allele. There were no differences in angiotensinogen expression between haplotypes on either background strain. The data suggest that the impact of angiotensinogen haplotypes on cardiovascular end points may be dependent on renin status and environmental influences, such as dietary sodium. These insights may help explain the discrepancies among observational studies that have examined roles for the -6A/235T and -6G/235M angiotensinogen haplotypes in varied human populations.


Subject(s)
Angiotensinogen/genetics , Blood Pressure/genetics , Alleles , Angiotensinogen/metabolism , Animals , Genetic Variation , Genotype , Haplotypes , Hypertension/genetics , Hypertension/metabolism , Mice , Mice, Transgenic , Renin/genetics , Renin/metabolism , Sodium, Dietary , Telemetry
12.
Circ Res ; 103(9): 940-7, 2008 Oct 24.
Article in English | MEDLINE | ID: mdl-18802024

ABSTRACT

Among naturally occurring polymorphisms in the 5' flanking region of the human angiotensinogen (AGT) gene, the -20 and -217 polymorphisms have the strongest effects on AGT regulation in AGT-expressing cells derived from liver, kidney, brain, and fat. These polymorphisms may affect allele-specific transcription factor binding, and the high-expressing alleles are both relatively common. We show herein that the -20C allele has higher transcriptional activity than -20A, and the -20A allele confers no additional transactivation potential beyond that of a mutated vector. Gel-shift assays show that upstream stimulatory factor (USF)1 and USF2 preferentially bind the -20C allele, whereas the -20A allele retains a low affinity USF binding site. Plasmid immunoprecipitation assays confirmed preferential association of USF1 with the -20C allele in transfected HepG2 cells. Chromatin immunoprecipitation confirmed that USF1 binds to the endogenous AGT -20C allele in CCF cells, the only cell line tested that carries the -20C allele, and to the human AGT promoter in liver and adipose tissue from transgenic mice. Transduction of AGT-expressing cells with short hairpin RNAs specifically targeting USF1 or USF2, resulted in cell- and allele-specific attenuation of AGT promoter activity. In vivo, knockdown of USF expression in the liver of transgenic mice expressing the -20C allele of AGT resulted in lower AGT expression, a decrease in circulating human AGT protein but no change in expression of GAPDH or hepatocyte nuclear factor-4alpha. We conclude that USF1 functionally and differentially regulates AGT expression via the -20 polymorphism and that the differential expression exhibited by -20 can be accounted for by differential association with USF1.


Subject(s)
5' Flanking Region , Angiotensinogen/metabolism , Polymorphism, Genetic , Promoter Regions, Genetic , Transcription, Genetic , Transcriptional Activation , Upstream Stimulatory Factors/metabolism , 3T3-L1 Cells , Adipose Tissue/metabolism , Angiotensinogen/genetics , Animals , Cell Line, Tumor , Chromatin Immunoprecipitation , Electrophoretic Mobility Shift Assay , Humans , Liver/metabolism , Mice , Mice, Transgenic , RNA Interference , RNA, Small Interfering/metabolism , Transfection , Upstream Stimulatory Factors/genetics
13.
Hypertension ; 49(3): 631-9, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17200439

ABSTRACT

A number of naturally occurring polymorphisms exist in the human angiotensinogen locus, some of which have been associated with essential hypertension, preeclampsia, and other medical disorders. However, to date there has been no comprehensive determination of the significance of specific haplotypes in relation to the regulation of angiotensinogen expression. We cloned the promoters extending from -1219 to +125 bp from 11 ethnically diverse individuals to acquire a representative cross-section of known haplotype diversity. Eight nonredundant haplotypes were identified, fused to luciferase, and studied for their effect on transcriptional regulation in human astrocyte, proximal tubule, and hepatocyte cell lines endogenously expressing angiotensinogen and in a mouse adipocyte cell line. The studies were carried out under baseline conditions, in the presence of the angiotensinogen enhancer, and in response to hormonal stimulation by dexamethasone, beta-estradiol, or testosterone. A statistical model was then constructed to assess the significance of individual polymorphisms. The polymorphisms with the greatest effect on transcription in these cell lines were located at -20 and -217. There were modest haplotype-specific effects of the angiotensinogen enhancer and no haplotype-specific effects of beta-estradiol, dexamethasone, or testosterone treatment. We conclude the following: (1) the -20 and -217 polymorphisms have the largest influence on angiotensinogen transcription, (2) other polymorphisms have a much smaller impact on angiotensinogen transcription, and (3) the transcriptional influence of the promoter polymorphisms may act cell specifically. Therefore, our data support a hypothesis that polymorphisms in the angiotensinogen promoter may act cell specifically to differentially regulate the level of angiotensinogen transcription in angiotensin-producing tissues.


Subject(s)
Angiotensinogen/biosynthesis , Angiotensinogen/genetics , Promoter Regions, Genetic/genetics , Adipose Tissue , Animals , Cell Line , Central Nervous System , Haplotypes , Humans , Kidney Tubules, Proximal , Liver , Mice , Neuroglia , Polymorphism, Genetic , Polymorphism, Single Nucleotide , Transcription, Genetic
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