Mechanism of Reductive Metabolism and Chiral Inversion of Proton Pump Inhibitors

Racemic proton pump inhibitors (PPIs) have been developed into pure enantiomers given superior pharmacokinetic profiles. However, after doses of single enantiomer PPIs, different degrees of chiral inversion were observed. We investigated the relationship between chiral inversion and reductive metabolism of PPIs, as well as the mechanism of reductive metabolism. In liver microsomes and Sprague-Dawley rats, PPI thioethers were stereoselectively oxidized to (R)- and (S)-PPIs, indicating that thioethers could be the intermediates of chiral inversion. By comparing the area under the plasma concentration-time curve ratios of thioether to rabeprazole under different routes of administration and blood sampling site, it was determined that thioether was mainly formed in the liver rather than the intestine. The formation rate of PPI thioethers in liver subcellular fractions was significantly higher than that in buffers. Sulfhydryl-blocking agents, such as N-ethylmaleimide, menadione, and ethacrynic acid, inhibited the reductive metabolism of PPIs in vitro, and their corresponding glutathione conjugates were observed. Similar amounts of thioethers were formed in glutathione solutions as in liver subcellular fractions, indicating that biologic reducing agents, instead of reductases, accelerated the reductive metabolism of PPIs. The reduction rates in glutathione solutions were ordered as follows: rabeprazole > omeprazole > lansoprazole > pantoprazole, which was consistent with the natural bond orbital charges of sulfur atoms in these compounds. In conclusion, PPIs were transformed into thioethers by biologic reducing agents in liver, and thioethers continued to be oxidized to two enantiomers, leading to chiral inversion. Furthermore, inhibiting oxidative metabolism of PPIs enhanced reductive metabolism and chiral inversion.

Birth population survey in Huai'an in 2015: perinatal-neonatal mortality and preterm birth rate in emerging regions in China

Objective: This survey followed the birth population-based study conducted in 2010 in Huai'an, Jiangsu Province, with the aim to estimate perinatal-neonatal mortality and preterm birth rate in emerging regions with similar maternal-fetal and neonatal care conditions in China.Materials and methods: Data of total births in 2015 were prospectively collected by regional perinatal network collaboration in Huai'an, a subprovincial region with a population of 5,644,500 and gross domestic production of 9082 USD per capita.Results: The 59,424 birth registries (including 59,023 live births and 167 stillbirths) corresponded to a birth rate of 10.5‰ and a Male-to-female ratio of 113.7:100. All births there were from 85, 16, and 6 level I, II, and III hospitals, with a delivery rate of 30.4, 40.2, and 29.4%, respectively. Of all births, 14.1% had pregnancy-associated comorbidities and complications, 54.4% (32,226/59,190) had cesarean delivery, and multiple pregnancies and birth defects occurred in 2.1% (1,250) and 5.5‰ (324), respectively. The mean birth weight was 3448 ± 507 g with 13.9% being macrosomia, and 2.86% (1695/59,190) low birth weight. Preterm birth rate was 4.06% (2404/59,190) with a mortality rate of 8.5%. There were 94.5% recorded as healthy newborns and 5.5% (3263) requiring hospitalization after birth. The perinatal and neonatal mortality rate was 5.2‰ (167 stillbirths, 139 early neonatal deaths) and 4.0‰, respectively. Compared with the 2010 survey, these data demonstrated generally improved status of perinatal-neonatal healthcare.Conclusions: The low rates of perinatal-neonatal mortality, preterm birth and preterm mortality suggest that the concept and study protocol of perinatal-neonatal healthcare in Huai'an may serve as the benchmark for estimating regional vital statistics and perinatal and neonatal outcomes.

[Effect of interleukin-6 promoter DNA methylation on the pathogenesis of systemic lupus erythematosus]

Objective: To analyze peripheral blood interleukin-6 (IL-6) promoter DNA methylation status and its clinical significance in patients with systemic lupus erythematosus (SLE). Methods: Blood samples of 41 adult patients with SLE and 20 healthy controls were collected.The methylation status of IL-6 promoter was determined by methylation specific polymerase chain reaction (MSP). The IL-6 expression was detected by real-time PCR.Correlations between IL-6 promoter methylation status and clinical features or laboratory findings in patients with SLE were analyzed. Results: The levels of IL-6 mRNA were significantly higher in peripheral blood of SLE.DNA methylation levels of IL-6 promoter were reduced in SLE patients as compared with healthy controls.The methylation status and expression of IL-6 in peripheral blood reflected the levels in peripheral blood mononuclear cells (PBMCs). Significantly positive correlation was found between IL-6 hypomethylation and renal disorder, as well as hypocomplementemia in patients with SLE. Conclusion: Hypomethylation of interleukin-6 promoter in peripheral blood might be involved in the etiology of SLE.

Herpes zoster-induced acute urinary retention: Two cases and literature review

We report two uncommon cases of acute urinary retention in Chinese patients caused by reactivation of sacral herpes zoster and requiring bladder drainage. Indwelling urinary catheterization, antiviral medication (ganciclovir), and physiotherapy with infrared light (830 nm) led to successful recovery of the micturition reflex in both cases.

The production characteristics of volatile organic compounds and their relation to growth status of Staphylococcus aureus in milk environment

In our previous research, 3-methyl-butanal and 3-methyl-butanoic acid were identified as representative and specific volatile organic compounds released by Staphylococcus aureus in broth. In this study, we explored the production of the 2 volatiles and their correlation to Staph. aureus growth in milk under different conditions. We found significant correlations between the production of 3-methyl-butanoic acid and cell counts of 5 Staph. aureus strains in sterile milk, and there were no obvious differences for its production among 5 tested strains. The intensities of the 2 volatiles were similar and positively correlated with bacterial counts in cultures at 25°C and 37°C despite delayed production of volatiles at 25°C; however, neither compound could be detected at 4°C. The production of 3-methyl-butanoic acid was strongly correlated with growth of Staph. aureus mixed with Streptococcus agalactiae, Escherichia coli O157:H7, and Shigella flexneri, whereas correlations for 3-methyl-butanal were not statistically significant. Compared with the monoculture of Staph. aureus, in mixed cultures, production of 3-methyl-butanal was decreased and that of 3-methyl-butanoic acid was comparatively higher. In pasteurized and raw milks, production of 3-methyl-butanoic acid was correlated with growth of Staph. aureus, and 3-methyl-butanoic acid could be detected when Staph. aureus populations reached 10⁶ to 10⁷ cfu/mL in pasteurized milk and 10⁵ to 10⁶ cfu/mL in raw milk; the correlations for 3-methyl-butanal were not statistically significant. Our results suggest that 3-methyl-butanoic acid is a more suitable marker for high counts of Staph. aureus in milk, whereas 3-methyl-butanal is a transient metabolite and easily depressed by environmental factors.

Abstract GS2-01: Discovery and characterization of an estrogen bound LncRNA in late-Stage breast cancer

Breast cancer is the second most common newly diagnosed cancer and the second leading cause of cancer death among women in the United States. Despite the proven benefits of adjuvant endocrine therapy in women with hormone receptor positive breast cancer, relapses still occur over 5 years after initial treatment with endocrine therapy, referred to as late-stage relapse. Currently, the mechanisms of driving late-stage relapse are poorly characterized. To date, breast cancer research has primarily focused on protein-coding genes thereby missing the emerging class of long intergenic non-coding RNAs (lncRNAs) that may serve as critical regulators of relapse. Furthermore, the current understanding of lncRNA function is still in its infancy representing a critical gap for translating lncRNA discoveries into real-world applications to benefit patient care. Several well-described examples indicate that lncRNAs may be master epigenetic regulators in cancer biology through their interactions with proteins regulating target gene expression. Therefore, we hypothesize that lncRNAs may interact with estrogen receptor alpha 1 (ESR1) to regulate genes promoting late-stage relapse. To address this, we performed a transcriptome analysis of tumors from a unique cohort of 24 patients that had late-stage relapse to discover a novel set of lncRNAs, most of which have not yet been characterized. Next, we used RNA Immunoprecipitation coupled with transcriptome sequencing (RIP-Seq) to identify transcripts bound to ESR1 in T47D cells. We discovered 217 lncRNAs bound to ESR1 of which 50 were up-regulated in late-stage breast cancer. We chose to focus the most up-regulated lncRNA in late-stage relapse. Since it is an unannotated lncRNA we will refer to it as 'LAte-Stage relapse ESR1-Bound lncRNA 1', or LASER-1. To further understand the interplay between LASER-1 and ESR1, cells endogenously expressing LASER-1 were subjected to partial digestion to preserve lncRNA and protein interactions. Protected RNA fragments were subsequently immunoprecipitated with ESR1 and quantified by qPCR to reveal specific ESR1 interaction sites within LASER-1. Next, we observed increased expression of LASER-1 in ER+ breast cancer cell lines. Notably, LASER-1 expression was elevated in MCF7 long-term estrogen deprived (MCF7 LTED) cells -- that have amplified ESR1 -- relative to parental MCF7 cells. To demonstrate that LASER-1 promotes oncogenic phenotypes we transiently silenced LASER-1 in two cell lines with high endogenous expression of LASER-1 (including MCF LTED) and observed a decrease in cellular proliferation and invasion. Subsequent gene expression analysis after silencing LASER-1 altered mRNA and protein levels of critical cell cycle genes (i.e., p27). Overall, this is the first study to discover ESR1 bound lncRNAs that may be contributing to late-stage relapse in breast cancer. In the short-term, our ongoing research may lead to significant breakthroughs establishing the importance of LASER-1 as a master regulator in late-stage relapse. In the longer-term, we envision this research may lead to the development of novel therapeutics targeting LASER-1 with the potential for rapid clinical translation.

Citation Format: Maher CA, Silva-Fisher J, Eteleeb A, Tang C, Perou C, Reis-Filho JS, Mardis ER, Ellis MJ. Discovery and characterization of an estrogen bound LncRNA in late-Stage breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr GS2-01.

Intonational speech prosody encoding in the human auditory cortex

Speakers of all human languages regularly use intonational pitch to convey linguistic meaning, such as to emphasize a particular word. Listeners extract pitch movements from speech and evaluate the shape of intonation contours independent of each speaker's pitch range. We used high-density electrocorticography to record neural population activity directly from the brain surface while participants listened to sentences that varied in intonational pitch contour, phonetic content, and speaker. Cortical activity at single electrodes over the human superior temporal gyrus selectively represented intonation contours. These electrodes were intermixed with, yet functionally distinct from, sites that encoded different information about phonetic features or speaker identity. Furthermore, the representation of intonation contours directly reflected the encoding of speaker-normalized relative pitch but not absolute pitch.

Experimental warming and antecedent fire alter leaf element composition and increase soil C:N ratio in sub-alpine open heathland

Plant communities in alpine ecosystems worldwide are being altered by climate warming. In the alpine open heathland of the Bogong High Plains, Australia, warming and fire have affected the growth and phenology of plants, and have recently been found to alter soil nutrient availability. We examined the effects of nine years of passive warming by open-top chambers and nine years post-fire on (i) the soluble and extractable nutrients and toxic elements available for plant uptake in the soil and (ii) on the element composition of leaves of seven dominant sub-alpine open heathland plants. Warming increased soil C, soil C:N, and decreased soil δ¹³C, indicating an accumulation of soil organic matter and C sequestration. Warming increased soil δ¹⁵N, indicating increased N mineralization, which concurred with the increased availability of NH₄⁺ (measured by ion-exchange membranes). Leaf element composition varied among the plant species in response to changes in soil element availabilities, suggesting the importance of species-specific knowledge. Warming decreased leaf N concentration and increased leaf C:N, generally in the plant community, and specifically in Asterolasia trymalioides, Carex breviculmis, Poa hiemata, and Rytidosperma nudiflorum. Warming increased soil P availability, but did not significantly affect leaf P in any species. Antecedent fire increased soil C:N, and decreased concentrations of Ca and Mg in Celmisia pugioniformis more than in the other species. The results suggest that warming and fire changed the nutrient composition of plants and increased soil C:N, which might lead to progressive N limitation in the alpine ecosystem.

[Application of " Internet Plus" AIDS prevention services among men who have sex with men in Guangzhou, China: results from 2010 to 2015]

Objective: To introduce the development strategy of " Internet Plus" AIDS prevention services and its implementation results from 2010 to 2015 in Guangzhou, China. Methods: A gay men's health column was created for an active website aimed at men who have sex with men(MSM), in collaboration with local community organizations and the Guangzhou CDC. We designed intervention tools(including scenario-based applications and HIV risk self-assessment systems)and an online HIV testing service platform, integrated with applied psychology and behavioral theory as well as the " Internet Plus" concept, to intervene in HIV infection risk factors among MSM. Data of clients who accessed the " Internet Plus" AIDS services from 2010 to 2015 were used to evaluate service operation. Six-year consecutive surveys, conducted between April and July of each service year, were collected using a national AIDS sentinel surveillance questionnaire. For each year of surveillance, information on HIV prevalence, HIV interventions received during the past year, unprotected anal intercourse in the past 6 months, and HIV testing in the past year were compared using the chi-squared(χ²)test, to roughly reflect the effect of"Internet Plus" AIDS prevention services. Results: As of 31 December 2015, a total of 34 395 MSM had received " Internet Plus" services and HIV testing. The number of MSM tested increased from 2 338 in 2010 to 8 054 in 2015. From 2010 to 2015, newly identified HIV cases in each year were 59, 166, 312, 283, 291, and 270, which accounted for 25.0%, 32.8%, 38.8%, 35.1%, 30.5%, and 23.2% of MSM HIV cases of Guangzhou, respectively. Sentinel surveillance data showed that during the study period, 3 047 MSM were investigated, with 405, 400, 401, 633, 608, and 600 each year, respectively. The proportion of participants who had received any HIV intervention during the past year was 74.3%(301), 70.8%(283), 83.3%(334), 85.0%(538), 69.1%(420), and 83.8%(503)each year, respectively(trend χ²=6.53, P=0.011). HIV testing done during the past year accounted for 44.0%(178), 44.3%(177), 49.4%(198), 53.4%(338), 56.1%(341), and 60.2%(361)each year, respectively(trend χ²=40.83, P<0.001). Unprotected anal intercourse in the past 6 months accounted for 59.3%(240), 62.0%(248), 56.6%(227), 57.0%(361), 48.4%(294), and 43.7%(262)each year, respectively(trend χ²=42.21, P<0.001). Conclusion: The"Internet Plus"AIDS prevention services in this study represent a manner to enhance traditional HIV prevention strategies. We found these services to be effective in implementation of the national AIDS control and prevention strategy, especially for the expansion of intervention, testing, and case identification among high-risk populations.