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The structural uniqueness of covalent organic frameworks (COFs) has brought great potential for their applications in photocatalysis. Two novel azo‐linked COFs AZO‐B‐COF and AZO‐T‐COF were successfully constructed by the monomer exchange method. Significantly, two as‐synthesized azo COFs presented a much higher photodegradation rate of 96 % and 51 % for AZO‐T‐COF and AZO‐B‐COF, respectively, which was in sharp contrast to the almost 0 degradation rate of imine COFs. And as expected, AZO‐T‐COF could be cycled at least 5 runs without a significant decrease in catalytic efficiency. Systematical experiments and theoretical calculations showed that comparing with imine COFs, conjugated structure of azo COFs broadened the visible‐light absorption range and improved the transfer efficiency of the photocarriers. The N‐rich azo bonds acted as an electron acceptor and made the materials better planarity. This work not only enriches COFs family but also demonstrated the superiority of azo‐linked COFs. [ABSTRACT FROM AUTHOR]

BACKGROUND The prevalence of many chronic conditions has increased among US adults. Many adults with hypertension have other chronic conditions. METHODS We estimated changes in the age-adjusted prevalence of multiple (≥3) chronic conditions, not including hypertension, using data from the National Health and Nutrition Examination Survey, from 1999–2000 to 2017–2020, among US adults with (n = 24,851) and without (n = 24,337 hypertension. Hypertension included systolic blood pressure (BP) ≥130 mm Hg, diastolic BP ≥80 mm Hg, or antihypertensive medication use. We studied 14 chronic conditions: arthritis, asthma, cancer, coronary heart disease, chronic kidney disease, depression, diabetes, dyslipidemia, hepatitis B, hepatitis C, heart failure, lung disease, obesity, and stroke. RESULTS From 1999–2000 to 2017–2020, the age-adjusted mean number of chronic conditions increased more among US adults with vs. without hypertension (2.2 to 2.8 vs. 1.7 to 2.0; P -interaction <0.001). Also, the age-adjusted prevalence of multiple chronic conditions increased from 39.0% to 52.0% among US adults with hypertension and from 26.0% to 30.0% among US adults without hypertension (P -interaction = 0.022). In 2017–2020, after age, gender, and race/ethnicity adjustment, US adults with hypertension were 1.94 (95% confidence interval: 1.72–2.18) times as likely to have multiple chronic conditions compared to those without hypertension. In 2017–2020, dyslipidemia, obesity, and arthritis were the most common 3 co-occurring chronic conditions among US adults with and without hypertension (age-adjusted prevalence 16.5% and 3.1%, respectively). CONCLUSIONS In 2017–2020, more than half of US adults with hypertension had ≥3 additional chronic conditions, a substantial increase from 20 years ago. [ABSTRACT FROM AUTHOR]

Metformin, the most widely prescribed antidiabetic drug, requires transporters to enter tissues involved in its pharmacologic action, including liver, kidney, and peripheral tissues. Organic cation transporter 3 (OCT3, SLC22A3), expressed ubiquitously, transports metformin, but its in vivo role in metformin response is not known. Using Oct3 knockout mice, the role of the transporter in metformin pharmacokinetics and pharmacodynamics was determined. After an intravenous dose of metformin, a 2-fold decrease in the apparent volume of distribution and clearance was observed in knockout compared with wild-type mice (P < 0.001), indicating an important role of OCT3 in tissue distribution and elimination of the drug. After oral doses, a significantly lower bioavailability was observed in knockout compared with wild-type mice (0.27 versus 0.58, P < 0.001). Importantly, metformin's effect on the plasma glucose concentration-time curve was reduced in knockout compared with wild-type mice (12 versus 30% reduction, respectively, P < 0.05) along with its accumulation in skeletal muscle and adipose tissue (P < 0.05). Furthermore, the effect of metformin on phosphorylation of AMP activated protein kinase, and expression of glucose transporter type 4 was absent in the adipose tissue of Oct3(-/-) mice. Additional analysis revealed that an OCT3 3' untranslated region variant was associated with reduced activity in luciferase assays and reduced response to metformin in 57 healthy volunteers. These findings suggest that OCT3 plays an important role in the absorption and elimination of metformin and that the transporter is a critical determinant of metformin bioavailability, clearance, and pharmacologic action.

Organic cation transporter 1, OCT1 (SLC22A1), is the major hepatic uptake transporter for metformin, the most prescribed antidiabetic drug. However, its endogenous role is poorly understood. Here we show that similar to metformin treatment, loss of Oct1 caused an increase in the ratio of AMP to ATP, activated the energy sensor AMP-activated kinase (AMPK), and substantially reduced triglyceride (TG) levels in livers from healthy and leptin-deficient mice. Conversely, livers of human OCT1 transgenic mice fed high-fat diets were enlarged with high TG levels. Metabolomic and isotopic uptake methods identified thiamine as a principal endogenous substrate of OCT1. Thiamine deficiency enhanced the phosphorylation of AMPK and its downstream target, acetyl-CoA carboxylase. Metformin and the biguanide analog, phenformin, competitively inhibited OCT1-mediated thiamine uptake. Acute administration of metformin to wild-type mice reduced intestinal accumulation of thiamine. These findings suggest that OCT1 plays a role in hepatic steatosis through modulation of energy status. The studies implicate OCT1 as well as metformin in thiamine disposition, suggesting an intriguing and parallel mechanism for metformin and its major hepatic transporter in metabolic function.

Supramolecular room temperature phosphorescence (RTP) materials are attractive due to their excellent RTP characteristics and water resistance. By evaluating the photophysical properties of HA/BisNpI‐doped materials, it is proved that hyaluronic acid (HA) is a promising matrix and the rigid plane N,N′‐(1,4‐phenylene)‐bis(1,8‐naphthalimide) (Ph‐BisNpI) is an excellent luminescent guest molecule for constructing RTP materials. Moreover, it is found that γ‐cyclodextrin (γ‐CD) can successfully bind BisNpI guest molecule. Accordingly, a tightly arranged ternary supramolecular system with HA as matrix, Ph‐BisNpI as the guest, and γ‐CD as the host is constructed by host‐guest interaction and hydrogen bonding. As expected, the obtained ternary supramolecular system HA/Ph@CD8 displays a superior RTP performance (52.7 ms longer lifetime than HA/Ph), water‐resistance, and even aqueous RTP (τ = 207 µs), which significantly extends the application of RTP in aqueous solution. These results are possibly attributed to the inclusion of γ‐CD on Ph‐BisNpI guest molecules and the self‐assembly of γ‐CD and HA to form a rigid hydrogen bonding network, which effectively inhibits the non‐radiative decay of Ph‐BisNpI and shields the triplet excitons from water and oxygen. Furthermore, the prepared ternary supramolecular RTP materials are successfully used as anticounterfeiting ink and exhibit broader application prospects in water environments. [ABSTRACT FROM AUTHOR]

BACKGROUND: Death certificate data indicate that hypertension may have increased as a contributing cause of death among US adults. Hypertension is not commonly recorded on death certificates although it contributes to a substantial proportion of cardiovascular disease (CVD) deaths. METHODS: We estimated changes in all-cause, CVD, and non-CVD mortality over 5 years of follow-up among 4 cohorts of US adults with hypertension using mortality follow-up data from National Health and Nutrition Examination Survey III in 1988 to 1994, and National Health and Nutrition Examination Survey cycles from 1999 to 2000 through 2015 to 2016 (n=20 927). Hypertension was defined as systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or antihypertensive medication use. Participants were grouped according to the date of their National Health and Nutrition Examination Survey study visit (1988–1994, 1999–2004, 2005–2010, 2011–2016). RESULTS: There were 2646, 1048, and 1598 all-cause, CVD, and non-CVD deaths, respectively. After age, gender, and race/ethnicity adjustment and compared with the 1988 to 1994 cohort, the hazard ratio of all-cause mortality was 0.88 (95% CI, 0.76–1.01) for the 1999 to 2004 cohort, 0.82 (95% CI, 0.70–0.95) for the 2005 to 2010 cohort, and 0.89 (95% CI, 0.75–1.05) for the 2011 to 2016 cohort (P trend=0.123). The age, gender, and race/ethnicity-adjusted hazard ratios for CVD mortality compared with the 1988 to 1994 cohort were 0.74 (95% CI, 0.60–0.90) for the 1999 to 2004 cohort, 0.61 (95% CI, 0.50–0.74) for the 2005 to 2010 cohort, and 0.57 (95% CI, 0.44–0.74) for the 2011 to 2016 cohort (P trend <0.001). There was no evidence of a change in CVD mortality between the 2005 to 2010 and 2011 to 2016 cohorts (P =0.661). Noncardiovascular mortality did not decline over the study period (P trend=0.145). CONCLUSIONS: The decline in CVD mortality among US adults with hypertension stalled after 2005 to 2010. [ABSTRACT FROM AUTHOR]

Membrane transporters play crucial roles in the cellular uptake and efflux of an array of small molecules including nutrients, environmental toxins, and many clinically used drugs. We hypothesized that common genetic variation in the proximal promoter regions of transporter genes contribute to observed variation in drug response. A total of 579 polymorphisms were identified in the proximal promoters (-250 to +50 bp) and flanking 5' sequence of 107 transporters in the ATP Binding Cassette (ABC) and Solute Carrier (SLC) superfamilies in 272 DNA samples from ethnically diverse populations. Many transporter promoters contained multiple common polymorphisms. Using a sliding window analysis, we observed that, on average, nucleotide diversity (pi) was lowest at approximately 300 bp upstream of the transcription start site, suggesting that this region may harbor important functional elements. The proximal promoters of transporters that were highly expressed in the liver had greater nucleotide diversity than those that were highly expressed in the kidney consistent with greater negative selective pressure on the promoters of kidney transporters. Twenty-one promoters were evaluated for activity using reporter assays. Greater nucleotide diversity was observed in promoters with strong activity compared to promoters with weak activity, suggesting that weak promoters are under more negative selective pressure than promoters with high activity. Collectively, these results suggest that the proximal promoter region of membrane transporters is rich in variation and that variants in these regions may play a role in interindividual variation in drug disposition and response.