Protein Binding Characteristics of the Principal Green Tea Catechins: A QCM Study Comparing Crude Extract to Pure EGCG.

Label-free detection methods such as the quartz crystal microbalance (QCM) are well suited to the analysis of molecular interactions in complex mixtures such as crude botanical extracts. In the present study, the binding characteristics of epigallocatechin gallate (EGCG) and crude green tea extract solutions to bovine serum albumin (BSA) have been investigated. The adsorbed mass levels onto BSA-functionalized surfaces were measured at various solution concentrations. Langmuir and Freundlich isotherms were used to model the adsorption data. The Langmuir isotherm better described the adsorption behavior with correlations of 0.68 and 0.70 for the EGCG and the crude extract solutions, respectively. The better fit of the Langmuir model indicates that adsorption occurs homogeneously and that aggregation is negligible. The mass saturation is estimated to be 58% higher for the crude green tea solution as compared to the pure EGCG solution (7.9 ng/cm2 for green tea and 5 ng/cm2 for EGCG). The increased adsorption for the crude extract indicates that the additional tea chemical constituents are binding to alternate sites on the protein molecule and that competitive binding is a nondominant effect. However, a reduced adsorption rate for the crude extract was also observed, indicating some presence of competitive mechanisms. The results demonstrate the utility of the QCM for the analysis of protein binding in crude mixtures as well as pure compounds.

Economic Evaluation of Quality Improvement Interventions Designed to Improve Glycemic Control in Diabetes: A Systematic Review and Weighted Regression Analysis.

OBJECTIVE: Quality improvement (QI) interventions can improve glycemic control, but little is known about their value. We systematically reviewed economic evaluations of QI interventions for glycemic control among adults with type 1 or type 2 diabetes. RESEARCH DESIGN AND METHODS: We used English-language studies from high-income countries that evaluated organizational changes and reported program and utilization-related costs, chosen from PubMed, EconLit, Centre for Reviews and Dissemination, New York Academy of Medicine's Grey Literature Report, and WorldCat (January 2004 to August 2016). We extracted data regarding intervention, study design, change in HbA1c, time horizon, perspective, incremental net cost (studies lasting ≤3 years), incremental cost-effectiveness ratio (ICER) (studies lasting ≥20 years), and study quality. Weighted least-squares regression analysis was used to estimate mean changes in HbA1c and incremental net cost. RESULTS: Of 3,646 records, 46 unique studies were eligible. Across 19 randomized controlled trials (RCTs), HbA1c declined by 0.26% (95% CI 0.17-0.35) or 3 mmol/mol (2 to 4) relative to usual care. In 8 RCTs lasting ≤3 years, incremental net costs were $116 (95% CI -$612 to $843) per patient annually. Long-term ICERs were $100,000-$115,000/quality-adjusted life year (QALY) in 3 RCTs, $50,000-$99,999/QALY in 1 RCT, $0-$49,999/QALY in 4 RCTs, and dominant in 1 RCT. Results were more favorable in non-RCTs. Our limitations include the fact that the studies had diverse designs and involved moderate risk of bias. CONCLUSIONS: Diverse multifaceted QI interventions that lower HbA1c appear to be a fair-to-good value relative to usual care, depending on society's willingness to pay for improvements in health.

Isolation and identification of three new chromones from the leaves of Pimenta dioica with cytotoxic, oestrogenic and anti-oestrogenic effects.

CONTEXT: Pimenta dioica (L.) Merr. (Myrtaceae) is used in Costa Rican traditional medicine for women's health. Our previous work showed that P. dioica extracts were oestrogenic. OBJECTIVES: This work identifies phytochemicals from P. dioica that are responsible for the plant's oestrogen-like activities. MATERIALS AND METHODS: P. dioica leaves were collected in Costa Rica in 2005. Fractions resulting from chromatographic separation of a methanol extract were tested at 50 µg/mL in a competitive oestrogen receptor-binding assay. Active compounds were isolated by HPLC and identified by NMR and MS. Pure compounds were tested at 1 µM in the oestrogen-responsive SEAP reporter gene assay. The effects on cell viability, cytotoxicity and apoptosis were investigated in breast cancer (MCF-7 and SK-BR3) and gastric cancer (AGS and NCI-N87) cell lines using the ApoTox-Glo and Caspase-Glo assays and qPCR. RESULTS: Quercitrin and three new chromones, including a 2-phenoxychromone, 6,8-di-C-methylcapillarisin (1) were isolated and identified. Compound 1 caused a 6.2-fold increase in SEAP expression at 1 µM (p < 0.05). This activity was blocked by the ER antagonist ICI 182,780. Compound 2 caused a 6.0-fold increase in SEAP, inhibited the growth of MCF-7, AGS and NCI-N87 cells (IC50 54.27, 38.13 and 51.22 µg/mL, respectively), and induced apoptosis via caspase 8 and increased the Bax/Bcl-2 mRNA ratio in MCF-7 cells. Compound 3 was anti-oestrogenic in MCF-7 cells. DISCUSSION AND CONCLUSIONS: Compounds from P. dioica have oestrogenic, anti-oestrogenic and cytotoxic effects that may explain the ethnomedical use of this plant.

Economic Evaluation of Quality Improvement Interventions Designed to Prevent Hospital Readmission: A Systematic Review and Meta-analysis.

Importance: Quality improvement (QI) interventions can reduce hospital readmission, but little is known about their economic value. Objective: To systematically review economic evaluations of QI interventions designed to reduce readmissions. Data Sources: Databases searched included PubMed, Econlit, the Centre for Reviews & Dissemination Economic Evaluations, New York Academy of Medicine's Grey Literature Report, and Worldcat (January 2004 to July 2016). Study Selection: Dual reviewers selected English-language studies from high-income countries that evaluated organizational or structural changes to reduce hospital readmission, and that reported program and readmission-related costs. Data Extraction and Synthesis: Dual reviewers extracted intervention characteristics, study design, clinical effectiveness, study quality, economic perspective, and costs. We calculated the risk difference and net costs to the health system in 2015 US dollars. Weighted least-squares regression analyses tested predictors of the risk difference and net costs. Main Outcomes and Measures: Main outcomes measures included the risk difference in readmission rates and incremental net cost. This systematic review and data analysis is reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Results: Of 5205 articles, 50 unique studies were eligible, including 25 studies in populations limited to heart failure (HF) that included 5768 patients, 21 in general populations that included 10 445 patients, and 4 in unique populations. Fifteen studies lasted up to 30 days while most others lasted 6 to 24 months. Based on regression analyses, readmissions declined by an average of 12.1% among patients with HF (95% CI, 8.3%-15.9%; P < .001; based on 22 studies with complete data) and by 6.3% among general populations (95% CI, 4.0%-8.7%; P < .001; 18 studies). The mean net savings to the health system per patient was $972 among patients with HF (95% CI, -$642 to $2586; P = .23; 24 studies), and the mean net loss was $169 among general populations (95% CI, -$2610 to $2949; P = .90; 21 studies), reflecting nonsignificant differences. Among general populations, interventions that engaged patients and caregivers were associated with greater net savings ($1714 vs -$6568; P = .006). Conclusions and Relevance: Multicomponent QI interventions can be effective at reducing readmissions relative to the status quo, but net costs vary. Interventions that engage general populations of patients and their caregivers may offer greater value to the health system, but the implications for patients and caregivers are unknown.

Association of a let-7 miRNA binding region of TGFBR1 with hereditary mismatch repair proficient colorectal cancer (MSS HNPCC).

The purpose of this study was to identify novel colorectal cancer (CRC)-causing alleles in unexplained familial CRC cases. In order to do so, coding regions in five candidate genes (MGMT, AXIN2, CTNNB1, TGFBR1 and TGFBR2) were sequenced in 11 unrelated microsatellite-stable hereditary non-polyposis CRC (MSS HNPCC) cases. Selected genetic variants were genotyped in a discovery set of 27 MSS HNPCC cases and 85 controls. One genetic variant, rs67687202, in TGFBR1 emerged as significant (P = 0.002), and it was genotyped in a replication set of 87 additional MSS HNPCC-like cases and 338 controls where it was also significantly associated with MSS HNPCC cases (P = 0.041). In the combined genotype data, rs67687202 was associated with a moderate increase in CRC risk (OR = 1.68; 95% CI = 1.13-2.50; P = 0.010). We tested a highly correlated SNP rs868 in 723 non-familial CRC cases compared with 629 controls, and it was not significantly associated with CRC risk (P = 0.370). rs868 is contained in a let-7 miRNA binding site in the 3'UTR of TGFBR1, which might provide a functional basis for the association in MSS HNPCC. In luciferase assays, the risk-associated allele for rs868 was associated with half the luciferase expression in the presence of miRNA let-7b-5p compared with protective allele, suggesting more binding of let-7b-5p and less TGFBR1 expression. Thus, rs868 potentially is a CRC risk-causing allele. Our results support the concept that rs868 is associated with lower TGFBR1 expression thereby increasing CRC risk.

Quartz crystal microbalance study of bovine serum albumin adsorption onto self-assembled monolayer-functionalized gold with subsequent ligand binding.

Adsorption characteristics of the model protein bovine serum albumin (BSA) onto gold surfaces were examined using a 5 MHz quartz crystal microbalance. Protein immobilization was executed in the presence and absence of a homogenous self-assembled monolayer (SAM) of NHS-terminated alkanethiols. BSA concentrations in the range of 3.2 × 10(-6) to 1.0 × 10(-3)mol/L were found to saturate both SAM-functionalized and non-functionalized surfaces with similar densities of 450 ± 26 ng/cm(2). The lack of functionalization dependence is attributed to the large protein size relative to the density of available binding sites in either surface condition. The BSA ligand 8-anilino-1-naphthalenesulfonic acid (ANS) was subsequently introduced to the immobilized BSA to determine any effects of the protein immobilization conditions on ligand binding. The rate of ANS binding to BSA was found to increase with increasing BSA concentration used in the immobilization step. This suggests that protein concentration affects morphology and ligand binding affinity without significantly altering adsorption quantity.

Analysis of the oxidative damage repair genes NUDT1, OGG1, and MUTYH in patients from mismatch repair proficient HNPCC families (MSS-HNPCC).

PURPOSE: Several studies have described molecular differences between microsatellite stable hereditary nonpolyposis colorectal cancer (MSS-HNPCC) and microsatellite unstable Lynch syndrome tumors (MSI-HNPCC). These differences highlight the possibility that other instability forms could explain cancer susceptibility in this group of families. The base excision repair (BER) pathway is the major DNA repair pathway for oxidative DNA damage. A defect in this pathway can result in DNA transversion mutations and a subsequent increased cancer risk. Mutations in MUTYH have been associated with increased colorectal cancer (CRC) risk while no association has been described for OGG1 or NUDT1. EXPERIMENTAL DESIGN: We performed mutational screening of the three genes involved in defense against oxidative DNA damage in a set of 42 MSS-HNPCC families. RESULTS: Eight rare variants and 5 frequent variants were found in MSS-HNPCC patients. All variants were previously described by other authors except variant c.285C>T in OGG1. Segregation studies were done and in silico programs were used to estimate the level of amino acid conservation, protein damage prediction, and possible splicing alterations. Variants OGG1 c.137G>A; MUTYH c.1187G>A were detected in Amsterdam I families and cosegregate with cancer. Analysis of OGG1 c.137G>A transcripts showed an inactivation of the splicing donor of exon 1. CONCLUSIONS: Two rare variants (OGG1 c.137G>A; MUTYH c.1187G>A) and one common polymorphism (NUDT1 c.426C>T) were associated with CRC risk. We show that the BER pathway can play a significant role in a number of MSS-HNPCC colorectal cancers. More studies could be of interest in order to gain further understanding of yet unexplained CRC susceptibility cases.

Susceptibility genetic variants associated with colorectal cancer risk correlate with cancer phenotype.

BACKGROUND & AIMS: Ten common low-penetrant genetic variants have been consistently associated with colorectal cancer (CRC) risk; little is known about the correlation between these variants and CRC phenotype. Characterization of such a correlation would improve CRC management and prevention programs. We assessed the association between these genetic variants and CRC phenotype in patients and modeled pairwise combinations to detect epistasis. METHODS: The validation population corresponded to a prospective, multicenter, population-based cohort (EPICOLON I) of 1096 patients with newly diagnosed CRC. The replication set was an independent, prospective, multicenter Spanish cohort (EPICOLON II) of 895 patients with newly diagnosed CRC. For individual single nucleotide polymorphism (SNP) association analyses, a multivariate method using logistic regression was applied in EPICOLON I and subsequently prospectively validated in EPICOLON II. Interactions between SNPs were assessed using the likelihood ratio test. RESULTS: Validated results confirmed that the C allele on 8q23.3 (rs16892766) was significantly associated with advanced-stage tumors (odds ratio [OR], 1.48; 95% confidence interval [CI], 1.15-1.90; P value = 4.9 x 10(-3)). The G allele on 8q24.21 (rs6983267) was more common in patients with a familial history of CRC (OR, 2.02; 95% CI, 1.35-3.03; P value = 3.9 x 10(-4)). The combination of rs6983267 on 8q24.21 and rs9929218 on 16q22.2 was associated with a history of colorectal adenoma (carriers of GG and AA, respectively; OR, 2.28; 95% CI, 1.32-3.93; P = 5.0 x 10(-4)). CONCLUSIONS: CRC susceptibility variants at 8q23.3, 8q24.21, and 16q22.2 appear to be associated with cancer phenotype. These findings might be used to develop screening and surveillance strategies.

Estrogenic and progestagenic effects of extracts of Justicia pectoralis Jacq., an herbal medicine from Costa Rica used for the treatment of menopause and PMS.

OBJECTIVES: To investigate the biological activities of Justicia pectoralis Jacq. (Acanthaceae), an herbal medicine used in Costa Rica (CR) for the management of menopausal symptoms and dysmenorrhea. STUDY DESIGN: The aerial parts of J. pectoralis were collected, dried and extracted in methanol. To establish possible mechanisms of action of JP for the treatment of menopausal symptoms, the estrogenic and progesterone agonists, and antiinflammatory activities were investigated. MAIN OUTCOME MEASURES: The methanol extract (JP-M) was tested in ER and PR binding assays, a COX-2 enzyme inhibition assay, the ERbeta-CALUX assay in U2-OS cells, as well as reporter and endogenous gene assays in MCF-7 K1 cells. RESULTS: The JP-M extract inhibited COX-2 catalytic activity (IC(50) 4.8 microg/mL); bound to both ERalpha and ERbeta (IC(50) 50 microg/mL and 23.1 microg/mL, respectively); induced estrogen-dependent transcription in the ERbeta-CALUX; and bound to the progesterone receptor (IC(50) 22.8 microg/mL). The extract also modulated the expression of endogenous estrogen responsive genes pS2, PR, and PTGES in MCF-7 cells at a concentration of 20 microg/mL. Activation of a 2 ERE-construct in transiently transfected MCF-7 cells by the extract was inhibited by the estrogen receptor antagonist ICI 182,780, indicating that the effects were mediated through the estrogen receptor. Finally, the extract weakly enhanced the proliferation of MCF-7 cells, however this was not statistically significant as compared with DMSO controls. CONCLUSIONS: Extracts of J. pectoralis have estrogenic, progestagenic and anti-inflammatory effects, and thus have a plausible mechanism of action, explaining its traditional use for menopause and PMS.

Aberrant DNA methylation in hereditary nonpolyposis colorectal cancer without mismatch repair deficiency.

BACKGROUND & AIMS: Approximately half of the families that fulfill Amsterdam criteria for Lynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) do not have evidence of the germline mismatch repair gene mutations that define this syndrome and result in microsatellite instability (MSI). The carcinogenic pathways and the best diagnostic approaches to detect microsatellite stable (MSS) HNPCC tumors are unclear. We investigated the contribution of epigenetic alterations to the development of MSS HNPCC tumors. METHODS: Colorectal cancers were divided into 4 groups: (1) microsatellite stable, Amsterdam-positive (MSS HNPCC) (N = 22); (2) Lynch syndrome cancers (identified mismatch repair mutations) (N = 21); (3) sporadic MSS (N = 92); and (4) sporadic MSI (N = 46). Methylation status was evaluated for CACNAG1, SOCS1, RUNX3, NEUROG1, MLH1, and long interspersed nucleotide element-1 (LINE-1). KRAS and BRAF mutation status was analyzed. RESULTS: MSS HNPCC tumors displayed a significantly lower degree of LINE-1 methylation, a marker for global methylation, than any other group. Although most MSS HNPCC tumors had some degree of CpG island methylation, none presented a high index of methylation. MSS HNPCC tumors had KRAS mutations exclusively in codon 12, but none harbored V600E BRAF mutations. CONCLUSIONS: Tumors from Amsterdam-positive patients without mismatch repair deficiency (MSS HNPCC) have certain molecular features, including global hypomethylation, that distinguish them from all other colorectal cancers. These characteristics could have an important impact on tumor behavior or treatment response. Studies are underway to further assess the cause and effects of these features.

Estrogenic effects of herbal medicines from Costa Rica used for the management of menopausal symptoms.

OBJECTIVE: Outcomes from the Women's Health Initiative have demonstrated adverse effects associated with hormone therapy and have prioritized the need to develop new alternative treatments for the management of menopause and osteoporosis. To this end, we have been investigating natural herbal medicines used by Costa Rican women to manage menopausal symptoms. METHODS: Seventeen plant species were collected and extracted in Costa Rica. To establish possible mechanisms of action and to determine their potential future use for menopause or osteoporosis, we investigated the estrogenic activities of the herbal extracts in an estrogen-reporter gene estrogen receptor (ER) beta-Chemically Activated Luciferase Expression assay in U2-OS cells and in reporter and endogenous gene assays in MCF-7 cells. RESULTS: Six of the plant extracts bound to the ERs. Four of the six extracts stimulated reporter gene expression in the ER-beta-Chemically Activated Luciferase Expression assay. All six extracts modulated expression of endogenous genes in MCF-7 cells, with four extracts acting as estrogen agonists and two extracts, Pimenta dioica and Smilax domingensis, acting as partial agonist/antagonists by enhancing estradiol-stimulated pS2 mRNA expression but reducing estradiol-stimulated PR and PTGES mRNA expression. Both P. dioica and S. domingensis induced a 2ERE-luciferase reporter gene in transient transfected MCF-7 cells, which was inhibited by the ER antagonist ICI 182,780. CONCLUSIONS: This work presents a plausible mechanism of action for many of the herbal medicines used by Costa Rican women to treat menopausal symptoms. However, it further suggests that studies of safety and efficacy are needed before these herbs should be used as alternative therapies to hormone therapy.

Effects of cranberry extracts and ursolic acid derivatives on P-fimbriated Escherichia coli, COX-2 activity, pro-inflammatory cytokine release and the NF-kappabeta transcriptional response in vitro.

Cranberry, the fresh or dried ripe fruit of Vaccinium macrocarpon Ait. (Ericaceae), is currently used as adjunct therapy for the prevention and symptomatic treatment of urinary tract infections. Data from clinical trials suggest that extracts of cranberry or cranberry juice reduce the bacterial load of E. coli and also suppress the inflammatory symptoms induced by E. coli infections. A methanol extract prepared from 10 kg of dehydrated cranberries did not directly inhibit the growth of E coli strains ATCC 700336 or ATCC 25922 in concentrations up to 256 mug/mL in vitro. However, the methanol extract (CR-ME) inhibited the activity of cyclooxygenase-2, with an IC(50) of 12.8 mug/mL. Moreover, CR-ME also inhibited the NF-kappabeta transcriptional activation in human T lymphocytes with an IC(50) of 19.4 mug/mL, and significantly (p < 0.01) inhibited the release of interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor-alpha from E. coli lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells in vitro, at a concentration of 50 mug/mL. The extract had no effect on inducible nitric oxide synthase activity in the murine macrophage cell line RAW 264.7. The compounds responsible for this activity were identified using a novel LC-MS based assay as ursolic acid and ursolic acid derivatives. Taken together, these data suggest CR-ME and its constituent chemical compounds target specific pathways involved in E. coli-induced inflammation.