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A History Of The Impacts Of Discriminatory Policies On Housing And Maternal And Infant Health In An Ohio Neighborhood. Health Aff (Millwood) 2024; 43:181-189. [PMID: 38315922 DOI: 10.1377/hlthaff.2023.01045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Community-level disinvestment and de facto segregation rooted in decades of discriminatory race-based policies and racism have resulted in unacceptably large infant mortality rates in racial minority neighborhoods across the US. Most community development and housing work, implemented with the goal of addressing health and social inequities, is designed to tackle current challenges in the condition of neighborhoods without a race-conscious lens assessing structural racism and discrimination. Using one historically segregated neighborhood-Linden, in Columbus, Ohio-we detail how state and local policies have affected the neighborhood and shaped neighborhood-level demographics and resources during the past 100 years. We explore how structural racism- and discrimination-informed strategic community reinvestment could provide a solution and yield lasting change.
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Abstract
Deep learning generative approaches provide an opportunity to broadly explore protein structure space beyond the sequences and structures of natural proteins. Here, we use deep network hallucination to generate a wide range of symmetric protein homo-oligomers given only a specification of the number of protomers and the protomer length. Crystal structures of seven designs are very similar to the computational models (median root mean square deviation: 0.6 angstroms), as are three cryo-electron microscopy structures of giant 10-nanometer rings with up to 1550 residues and C33 symmetry; all differ considerably from previously solved structures. Our results highlight the rich diversity of new protein structures that can be generated using deep learning and pave the way for the design of increasingly complex components for nanomachines and biomaterials.
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Connecting past to present: Examining different approaches to linking historical redlining to present day health inequities. PLoS One 2022; 17:e0267606. [PMID: 35587478 PMCID: PMC9119533 DOI: 10.1371/journal.pone.0267606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 04/12/2022] [Indexed: 11/18/2022] Open
Abstract
In the 1930’s, the Home Owner Loan Corporation (HOLC) drafted maps to quantify variation in real estate credit risk across US city neighborhoods. The letter grades and associated risk ratings assigned to neighborhoods discriminated against those with black, lower class, or immigrant residents and benefitted affluent white neighborhoods. An emerging literature has begun linking current individual and community health effects to government redlining, but each study faces the same measurement problem: HOLC graded area boundaries and neighborhood boundaries in present-day health datasets do not match. Previous studies have taken different approaches to classify present day neighborhoods (census tracts) in terms of historical HOLC grades. This study reviews these approaches, examines empirically how different classifications fare in terms of predictive validity, and derives a predictively optimal present-day neighborhood redlining classification for neighborhood and health research.
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Experiences of racial discrimination in the medical setting and associations with medical mistrust and expectations of care among black patients seeking addiction treatment. J Subst Abuse Treat 2021; 133:108551. [PMID: 34244014 DOI: 10.1016/j.jsat.2021.108551] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 06/16/2021] [Accepted: 06/20/2021] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Experiences of racial discrimination in the medical setting are common among Black patients and may be linked to mistrust in medical recommendations and poorer clinical outcomes. However, little is known about the prevalence of experiences of racial mistreatment by healthcare workers among Black patients seeking addiction treatment, or how these experiences might influence Black patients' medical mistrust or expectations of care. METHODS Participants were 143 Black adults recruited consecutively from two university addiction treatment facilities in Columbus, Ohio. All participants completed validated surveys assessing perceptions of prior racial discrimination in the medical setting and group-based medical mistrust. Participants were also asked a series of questions about their expectations of care with regard to racial discrimination and addiction treatment. Descriptive analyses were used to characterize the sample with regard to demographics, perceived racial discrimination and medical mistrust. Kendall tau-b correlations assessed relationships between racial discrimination, mistrust and expectations of care. RESULTS Seventy-nine percent (n = 113) of participants reported prior experiences of racial discrimination during healthcare. Racial discrimination in the medical setting was associated with greater mistrust in the medical system and worse expectations regarding racial discrimination in addiction treatment including delays in care-seeking due to concern for discrimination, projected non-adherence and fears of discrimination-precipitated relapse. CONCLUSIONS Black patients seeking addiction treatment commonly report experiencing racial discrimination by healthcare workers which may be associated with mistrust in the medical system and expectations of care. Strategies to eliminate and mitigate experiences of racial discrimination may improve addiction treatment receptivity and engagement.
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Racial And Ethnic Inequities In Children's Neighborhoods: Evidence From The New Child Opportunity Index 2.0. Health Aff (Millwood) 2021; 39:1693-1701. [PMID: 33017244 DOI: 10.1377/hlthaff.2020.00735] [Citation(s) in RCA: 105] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neighborhoods influence children's health, so it is important to have measures of children's neighborhood environments. Using the Child Opportunity Index 2.0, a composite metric of the neighborhood conditions that children experience today across the US, we present new evidence of vast geographic and racial/ethnic inequities in neighborhood conditions in the 100 largest metropolitan areas in the US. Child Opportunity Scores range from 20 in Fresno, California, to 83 in Madison, Wisconsin. However, more than 90 percent of the variation in neighborhood opportunity happens within metropolitan areas. In 35 percent of these areas the Child Opportunity Gap (the difference between Child Opportunity Scores in very low- and very high-opportunity neighborhoods) is higher than across the entire national neighborhood distribution. Nationally, the Child Opportunity Score for White children (73) is much higher than for Black (24) and Hispanic (33) children. To improve children's health and well-being, the health sector must move beyond a focus on treating disease or modifying individual behavior to a broader focus on neighborhood conditions. This will require the health sector to both implement place-based interventions and collaborate with other sectors such as housing to execute mobility-based interventions.
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Neighborhood-Level Lead Paint Hazard for Children under 6: A Tool for Proactive and Equitable Intervention. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18052471. [PMID: 33802321 PMCID: PMC7967606 DOI: 10.3390/ijerph18052471] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/24/2021] [Accepted: 02/27/2021] [Indexed: 11/18/2022]
Abstract
Lead is well known for its adverse health effects on children, particularly when exposure occurs at earlier ages. The primary source of lead hazards among young children is paint used in buildings built before 1978. Despite being 100% preventable, some children remain exposed and state and local policies often remain reactive. This study presents a methodology for planners and public health practitioners to proactively address lead risks among young children. Using geospatial analyses, this study examines neighborhood level measurement of lead paint hazard in homes and childcare facilities and the concentration of children aged 0–5. Results highlight areas of potential lead paint hazard hotspots within a county in the Midwestern state studied, which coincides with higher concentration of non-white children. This places lead paint hazard in the context of social determinants of health, where existing disparity in distribution of social and economic resources reinforces health inequity. In addition to being proactive, lead poisoning intervention efforts need to be multi-dimensional and coordinated among multiple parties involved. Identifying children in higher lead paint hazard areas, screening and treating them, and repairing their homes and childcare facilities will require close collaboration of healthcare professionals, local housing and planning authorities, and community members.
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The child opportunity index: improving collaboration between community development and public health. Health Aff (Millwood) 2016; 33:1948-57. [PMID: 25367989 DOI: 10.1377/hlthaff.2014.0679] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Improving neighborhood environments for children through community development and other interventions may help improve children's health and reduce inequities in health. A first step is to develop a population-level surveillance system of children's neighborhood environments. This article presents the newly developed Child Opportunity Index for the 100 largest US metropolitan areas. The index examines the extent of racial/ethnic inequity in the distribution of children across levels of neighborhood opportunity. We found that high concentrations of black and Hispanic children in the lowest-opportunity neighborhoods are pervasive across US metropolitan areas. We also found that 40 percent of black and 32 percent of Hispanic children live in very low-opportunity neighborhoods within their metropolitan area, compared to 9 percent of white children. This inequity is greater in some metropolitan areas, especially those with high levels of residential segregation. The Child Opportunity Index provides perspectives on child opportunity at the neighborhood and regional levels and can inform place-based community development interventions and non-place-based interventions that address inequities across a region. The index can also be used to meet new community data reporting requirements under the Affordable Care Act.
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A validated web-based tool to display individualised Crohn's disease predicted outcomes based on clinical, serologic and genetic variables. Aliment Pharmacol Ther 2016; 43:262-71. [PMID: 26567467 DOI: 10.1111/apt.13460] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 08/25/2015] [Accepted: 10/11/2015] [Indexed: 12/12/2022]
Abstract
BACKGROUND Early treatment for Crohn's disease (CD) with immunomodulators and/or anti-TNF agents improves outcomes in comparison to a slower 'step up' algorithm. However, there remains a limited ability to identify those who would benefit most from early intensive therapy. AIM To develop a validated, individualised, web-based tool for patients and clinicians to visualise individualised risks for developing Crohn's disease complications. METHODS A well-characterised cohort of adult patients with CD was analysed. Available data included: demographics; clinical characteristics; serologic immune responses; NOD2 status; time from diagnosis to complication; and medication exposure. Cox proportional analyses were performed to model the probability of developing a CD complication over time. The Cox model was validated externally in two independent CD cohorts. Using system dynamics analysis (SDA), these results were transformed into a simple graphical web-based display to show patients their individualised probability of developing a complication over a 3-year period. RESULTS Two hundered and forty three CD patients were included in the final model of which 142 experienced a complication. Significant variables in the multivariate Cox model included small bowel disease (HR 2.12, CI 1.05-4.29), left colonic disease (HR 0.73, CI 0.49-1.09), perianal disease (HR 4.12, CI 1.01-16.88), ASCA (HR 1.35, CI 1.16-1.58), Cbir (HR 1.29, CI 1.07-1.55), ANCA (HR 0.77, CI 0.62-0.95), and the NOD2 frameshift mutation/SNP13 (HR 2.13, CI 1.33-3.40). The Harrell's C (concordance index for predictive accuracy of the model) = 0.73. When applied to the two external validation cohorts (adult n = 109, pediatric n = 392), the concordance index was 0.73 and 0.75, respectively, for adult and pediatric patients. CONCLUSIONS A validated, web-based tool has been developed to display an individualised predicted outcome for adult patients with Crohn's disease based on clinical, serologic and genetic variables. This tool can be used to help providers and patients make personalised decisions about treatment options.
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270. AEG-1 is associated with invasion and poor prognosis in colorectal cancer. Eur J Surg Oncol 2014. [DOI: 10.1016/j.ejso.2014.08.262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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273. Single port transanal minimally invasive surgery for rectal tumours under spinal anesthesia. Eur J Surg Oncol 2014. [DOI: 10.1016/j.ejso.2014.08.265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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1146 POSTER Pro-angiogenic Factor Cyr61 is Linked to Colorectal Cancer Development and Prognosis. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)70789-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Factors influencing the cytotoxicity of zinc oxide nanoparticles: particle size and surface charge. ACTA ACUST UNITED AC 2011. [DOI: 10.1088/1742-6596/304/1/012044] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Abstract
446 Background: Angiogenic factorCysteine-rich 61 (Cyr61) is a member of the CCN protein family that has been implicated in diverse biological processes such as cell adhesion, proliferation, angiogenesis, and tumorigenesis. An altered expression of Cyr61 is found to be associated with several human cancers. However, the correlation of expression of Cyr61 protein and clinical features of colorectal cancer remains unknown. Methods: Cyr61 expression in colorectal cancer and normal tissues was evaluated by Western blot analysis. Immunohistochemical staining was carried out using tissue microassay (TMA) to examine the expression status of Cyr61. Correlations of Cyr61 over-expression with various clinicopathologic factors were also determined. Statistical analysis was performed to explore the links between expression of the Cyr61 and clinicopathological parameters. Results: On Western blot analysis Cyr61 up-regulation was observed in colorectal cancer tissues (17/21, 80.9%). In 234 colorectal cancers, tumor tissue microarray revealed significantly up-regulated Cyr61 protein expression in colorectal cancer tissues versus normal tissues adjacent to tumor. Cyr61 expression was high in 136 of 234 cases of colorectal carcinomas (58.1%). Cyr61 over-expression was significantly associated with TNM stage (p=0.012) and regional lymph node involvement (p=0.018). Kaplan-Meier survival analysis showed that over-expression of Cyr61 was related to poor survival of colorectal cancer patients (p=0.031). But significant associations were not found between CYR61 expression versus tumor grade, age and gender. Conclusions: Our results suggest that Cyr61 is highly expressed in colorectal carcinomas and Cyr61 may play a role in the progression of colorectal cancers. Also, Cyr61 might be a new molecular marker to predict the prognosis and serve as valuable targets for therapeutic intervention of patients with colorectal carcinoma. No significant financial relationships to disclose.
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Expression changes of angiogenic factors in rectal carcinomas after neoadjuvant chemoradiotherapy. J Clin Oncol 2010. [DOI: 10.1200/jco.2010.28.15_suppl.e14061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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MP-12.10: The Effect of Orchiectomy on Contralateral Testicular Injury after Testicular Torsion in the Rat. Urology 2009. [DOI: 10.1016/j.urology.2009.07.897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6103 Expression and role of placenta growth factor (PlGF) on colorectal carcinomas. EJC Suppl 2009. [DOI: 10.1016/s1359-6349(09)71198-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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The association of expression level of PRL-3 mRNA and liver metastasis in primary colorectal cancer. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71653-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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POS-02.67: The efficacy of transurethral resection of the prostate in patients with large prostate (over 80 g). Urology 2007. [DOI: 10.1016/j.urology.2007.06.708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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MP-16.18. Urology 2006. [DOI: 10.1016/j.urology.2006.08.400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Cyclin G1 overcomes radiation-induced G2 arrest and increases cell death through transcriptional activation of cyclin B1. Cell Death Differ 2005; 13:1475-84. [PMID: 16322753 DOI: 10.1038/sj.cdd.4401822] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Although cyclin G1 has been implicated in certain p53-related biological phenomena, other aspects of its function remain unclear. Here we report hitherto unknown mechanism by which cyclin G1 increases radiation sensitivity by regulating the level of cyclin B1. Overexpression of cyclin G1 was observable in lung carcinoma tissues. Irradiation of human lung cells with cyclin G1 overexpression resulted in increased cell death and gamma-H2AX foci suggesting that cyclin G1 rendered the cells more susceptible to DNA damage. Enhanced radiosensitivity by cyclin G1 was correlated with increased cyclin B1, CDC2/cyclin B1 complex, and MPM2. Cell cycle synchronization clearly showed coexpression of cyclin G1 and cyclin B1 in G2/M phase. Depletion of cyclin G1 by interference RNA revealed that cyclin G1 regulated transcription of cyclin B1 in a p53-independent manner, and confirmed that the increased mitotic cells and cell death by cyclin G1 were dependent upon cyclin B1. Therefore, our data suggest that cyclin G1 enhanced radiation sensitivity by overriding radiation-induced G2 arrest through transcriptional upregulation of cyclin B1.
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Quantitation of niflumic acid in human plasma by high-performance liquid chromatography with ultraviolet absorbance detection and its application to a bioequivalence study of talniflumate tablets. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 821:215-20. [PMID: 15921965 DOI: 10.1016/j.jchromb.2005.05.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2005] [Accepted: 05/11/2005] [Indexed: 11/18/2022]
Abstract
A rapid and simple HPLC method with UV detection (288 nm) was developed and validated for quantitation of niflumic acid in human plasma, the active metabolite of talniflumate. After precipitation with 100% methanol containing the internal standard, indomethacin, the analysis of the niflumic acid level in the plasma samples was carried out using a reverse phase C18 CAPCELL PAK (5 microm, 4.6 mm x 250 mm) column. The chromatographic separation was accomplished with an isocratic mobile phase consisting of a mixture of 0.1M sodium acetate in water and acetonitrile (37:63, v/v), adjusted to pH 6.4. This HPLC method was validated by examining its precision and accuracy for inter- and intra-day runs in a linear concentration range of 0.02-5.00 microg/mL. Stability of niflumic acid in plasma was excellent, with no evidence of degradation during sample processing (autosampler) and 30 days storage in a freezer. This validated method was successfully applied to the bioequivalence study of talniflunate in healthy volunteers.
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Molecular cloning and functional characterization of a type-I neurotensin receptor (NTR) and a novel NTR from the bullfrog brain. J Mol Endocrinol 2005; 34:793-807. [PMID: 15956348 DOI: 10.1677/jme.1.01709] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Neurotensin (NT) is a tridecapeptide that functions as a neurotransmitter and neuromodulator in the nervous system. To date, three different types of NT receptor (NTR), NTR1, NTR2 and NTR3, have been identified only in mammalian species. In the present study we isolated the cDNAs for an NTR1 and a novel NTR in the bullfrog brain, designated bfNTR1 and bfNTR4 respectively. bfNTR1 and bfNTR4 encode 422- and 399-amino acid residue proteins respectively. bfNTR1 has a 64% amino acid identity with mammalian NTR1, and 34-37% identity with mammalian NTR2. bfNTR4 exhibits 43% and 45-47% identity with mammalian NTR1 and NTR2 respectively. Both receptors are mainly expressed in the brain and pituitary. bfNTR1 triggers both CRE-luc, a protein kinase A (PKA)-specific reporter, and c-fos-luc, a PKC-specific reporter, activities, indicating that bfNTR1 can activate PKA- and PKC-linked signaling pathways. However, bfNTR4 appears to be preferentially coupled to the PKA-linked pathway as it induces a higher CRE-luc activity than c-fos-luc activity. bfNTRs exhibit different pharmacological properties as compared with mammalian NTRs. Mammalian NTR1 but not NTR2 responds to NT, whereas both bfNTR1 and bfNTR4 show a high sensitivity to NT. SR 48692 and SR 142948A, antagonists for mammalian NTR1 but agonists for mammalian NTR2, function as antagonists for both bfNTR1 and bfNTR4. In conclusion, this report provides the first molecular, pharmacological and functional characterization of two NTRs in a non-mammalian vertebrate. These data should help to elucidate the phylogenetic history of the G protein-coupled NTRs in the vertebrate lineage as well as the structural features that determine their pharmacological properties.
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Serum response factor is alternatively spliced in colon cancer. J Surg Res 2003. [DOI: 10.1016/j.jss.2003.08.168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Characterization of the selectivity and mechanism of cytochrome P450 inhibition by dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate. Drug Metab Dispos 2001; 29:1555-60. [PMID: 11717174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
In vitro studies with human liver microsomes and cytochrome P450 (P450) prototype substrates were performed to characterize the selectivity and mechanism of inhibition of P450 by dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate (DDB). DDB was found to be a strong inhibitor of testosterone 6beta-hydroxylation activity (CYP3A4) with a K(i) value of 0.27 +/- 0.21 microM. At higher concentrations, DDB marginally inhibited caffeine N(3)-demethylation (CYP1A2), diclofenac 4'-hydroxylation (CYP2C9), and dextromethorphan O-demethylation (CYP2D6) activities, but this compound had no effect on CYP2A6-, CYP2C19-, and CYP2E1-mediated reactions. Spectral analysis indicated that the formation of metabolite-P450 complex having absorbance at 456 nm was concentration-dependent; 5 to 33% of the total P450 was complexed in rat and human liver microsomes after a 5-min incubation with DDB. In addition, microsomal incubations with DDB in the presence of NADPH resulted in a loss of spectral P450 content, which was restored after adding K(3)Fe(CN)(6). This complex formation resulted in a time-dependent loss of CYP3A-catalyzed marker activity (testosterone 6beta-hydroxylation) in human liver microsomes. The inhibition was only partially restored upon dialysis. These results collectively suggest that formation of a metabolite-CYP3A complex with DDB was responsible for the CYP3A-selective time-dependent loss of catalytic function of CYP3A.
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Abstract
The 1400 kb genomic sequence between the markers D16S406 and D16S423 on chromosome 16p13.3 has been recently sequenced and the interval contains a transcription factor, AP-4, that was identified as a ligand for immunoglobulin-kappa promoter E-box elements,(1)suggesting that AP-4 may be related to immunodeficiency diseases. In addition, chromosome 16p13.3 includes a number of genes including the PKD1 gene,(2,3)the autosomal dominant polycystic kidney disease (ADPKD) gene. ADPKD is characterized by progressive development and enlargement of renal cysts.(4)The size and genomic complexity of the PKD1 gene makes it impractical to detect mutations for prenatal diagnosis. Therefore, pedigree-based linkage analysis remains useful for diagnosis of ADPKD. To increase the number of polymorphic markers in the region around AP-4 gene, we performed database searches of 1400 kb of genomic sequence (from contig NT000677 to NT001573: http://www.ncbi.gov/genome/seq.cgi) across the 16p13.3. A number of dinucleotide or tetranucleotide repeats were found, and 20 microsatellites that contain more than 15 contiguous repeats were chosen for further investigation.
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Abstract
In this genomics and proteomics age, highly functionalized natural products or natural-product-like compounds are likely to play important roles in understanding the functions of emerging biological targets because they serve as small-molecule chemical probes in modulating a target's specific actions (i.e. activation or deactivation). Development of stereoselective reaction-derived methods on solid phase provides a means of obtaining functionalized chiral core structures that may be used for high-throughout syntheses.
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Determination of aloesin in rat plasma using a column-switching high-performance liquid chromatographic assay. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 754:121-6. [PMID: 11318406 DOI: 10.1016/s0378-4347(00)00593-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A column-switching high-performance liquid chromatography (HPLC) method for the determination of aloesin in rat plasma using column-switching and ultraviolet (UV) absorbance detection is described. Plasma was directly injected onto the HPLC system consisting of a clean-up column, a concentrating column, and an analytical column, which were connected with a six-port switching valve. The determination of aloesin was accurate and repeatable, with a limit of quantitation of 10 ng/ml in plasma. The standard calibration curve for aloesin was linear (r=0.998) over the concentration range of 10-1000 ng/ml in rat plasma. The intra- and inter-day assay variabilities of aloesin ranged from 1.0 to 4.7% and 1.1 to 8.8%, respectively. This highly sensitive and simple method has been successfully applied to a pharmacokinetic study after oral administration of aloesin to rats.
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Column-switching high-performance liquid chromatographic assay for determination of asiaticoside in rat plasma and bile with ultraviolet absorbance detection. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1999; 732:357-63. [PMID: 10517358 DOI: 10.1016/s0378-4347(99)00302-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A column-switching high-performance liquid chromatography (HPLC) method is described for the determination of asiaticoside in rat plasma and bile using column-switching and ultraviolet (UV) absorbance detection. Plasma was simply deproteinated with acetonitrile prior to injection and bile was directly injected onto the HPLC system consisting of a clean-up column, a concentrating column, and an analytical column, which were connected with two six-port switching valves. Detection of asiaticoside was accurate and repeatable, with a limit of quantification of 0.125 microg/ml in plasma and 1 microg/ml in bile. The calibration curves were linear in a concentration range of 0.125-2.5 microg/ml and 1-20 microg/ml for asiaticoside in rat plasma and bile, respectively. This method has been successfully applied to determine the level of asiaticoside in rat plasma and bile samples from pharmacokinetics and biliary excretion studies.
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Disposition and metabolism of 2-(2''(1'',3''-dioxolan-2-yl)-2- methyl-4-(2'-oxopyrrolidin-1-Yl)-6-nitro-2h-1-benzopyran (SKP-450) in rats. Drug Metab Dispos 1999; 27:510-6. [PMID: 10101146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
The disposition and metabolism of the new antihypertensive agent 2-(2"(1", 3"-dioxolan-2-yl)-2-methyl-4-(2'-oxopyrrolidin-1-yl)-6-nitro -2H-1-benzopyran (SKP-450) were investigated in male rats after single oral and i.v. doses of 14C-labeled compound. After an oral 2.0 mg/kg dose, mean radiocarbon recovery was 98.2 +/- 2.3% with 31.1 +/- 7.3% in the feces and 67.1 +/- 14.3% in the urine. Biliary excretion of radioactivity for the first 24-h period was approximately 40%, suggesting that SKP-450 is cleared either by hepatobiliary excretion or by renal excretion. SKP-450 was well absorbed; bioavailability calculated on the basis of radioactivity was 68 to 97%. Tissue distribution of the radioactivity was widespread with high concentrations in the liver and kidney but low central nervous system penetration. Radio-HPLC analysis of bile and urine from rats indicated the extensive metabolism of SKP-450 into oxidative metabolites. Oxidative metabolism of the dioxolanyl ring resulted in an aldehyde intermediate, subsequently confirmed in vitro, which was further oxidized to the corresponding carboxylic acid (M1) or reduced to the corresponding alcohol (M3). No parent drug was detected in the urine or bile. Glucuronide conjugate of M3 was also detected in urine and bile, accounting for 5.8 +/- 2.1 and 8.9 +/- 3. 7% of the excreted radioactivity, respectively. Quantitative data obtained from plasma samples suggest that the majority of circulating radioactivity was associated with metabolites. Our results suggest that the long duration of pharmacological activity of SKP-450 (>10 h) is largely attributable to its metabolites.
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