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Extending the bandwidth of triplet excited-state absorption in transition-metal complexes is appealing for developing broadband reverse saturable absorbers. Targeting this goal, five bis-terdentate iridium(III) complexes ( Ir1 - Ir5 ) bearing trans -bis-cyclometalating (C^N^C) and 4'-R-2,2':6',2″-terpyridine (4'-R-tpy) ligands were synthesized. The effects of the structural variation in cyclometalating ligands and substituents at the tpy ligand on the photophysics of these complexes have been systematically explored using spectroscopic methods (i.e., UV-vis absorption, emission, and transient absorption spectroscopy) and time-dependent density functional theory (TDDFT) calculations. All complexes exhibited intensely structured 1 π,π* absorption bands at <400 nm and broad charge transfer ( 1 CT)/ 1 π,π* transitions at 400-600 nm. Ligand structural variations exerted a very small effect on the energies of the 1 CT/ 1 π,π* transitions; however, they had a significant effect on the molar extinction coefficients of these absorption bands. All complexes emitted featureless deep red phosphorescence in solutions at room temperature and gave broad-band and strong triplet excited-state absorption ranging from the visible to the near-infrared (NIR) spectral regions, with both originating from the 3 π,π*/ 3 CT states. Although alteration of the ligand structures influenced the emission energies slightly, these changes significantly affected the emission lifetimes and quantum yields, transient absorption spectral features, and the triplet excited-state quantum yields of the complexes. Except for Ir3 , the other four complexes all manifested reverse saturable absorption (RSA) upon nanosecond laser pulse excitation at 532 nm, with the decreasing trend of RSA following Ir2 ≈ Ir4 > Ir1 > Ir5 > Ir3 . The RSA trend corresponded well with the strength of the excited-state and ground-state absorption differences (ΔOD) at 532 nm for these complexes.

Background: Cigarette smoking is associated with shorter telomere lengths in adults, but evidence on the effect of prenatal tobacco exposure is limited. We aimed to investigate the association between prenatal second-hand smoke exposure and newborn telomere length., Methods: We recruited 762 mother-newborn pairs from Wuhan Children's Hospital (Wuhan Maternal and Child Healthcare Hospital) between November 2013 and March 2015. Information on second-hand smoke exposure was obtained via questionnaires. Relative telomere length was measured in DNA extracted from umbilical cord blood. We used linear regression to assess the associations between prenatal second-hand smoke exposure and newborn telomere length., Results: In the fully adjusted model, prenatal second-hand smoke exposure was associated with 9.7% shorter newborn telomere length (percent difference: -9.7%; 95% confidence interval (CI): -15.0, -4.0). The estimate for boys was lower (percent difference: -10.9%; 95% CI: -18.6, -2.5) than that for girls (percent difference: -8.5%; 95% CI: -15.8, -0.5), but the interaction term between newborn sex and prenatal second-hand smoke was not significant (P = 0.751)., Conclusions: This study demonstrated that prenatal second-hand smoke exposure may be a preventable risk factor for accelerated biological aging in the intrauterine stage, and further suggested possible sex differences in the susceptibility to prenatal second-hand smoke.

Purpose of Review: To evaluate the status of elevated blood pressure in Chinese children and adolescents, and identify potential influence factors., Recent Findings: We searched PubMed, the Web of science, the WanFang, the VIP, and the CNKI to identify articles that were published from Jan 1, 1997, to May 30, 2019. We used random effects models to estimate the pooled prevalence of elevated blood pressure, and heterogeneity among the studies was assessed with Cochran's Q statistic. The potential source of heterogeneity was explored by meta-regression and subgroup comparisons using Q test based on ANOVA. Fifty-nine studies were included in the qualitative synthesis and the prevalence of elevated blood pressure ranged from 2.2 to 26.4%. The meta-analysis included 25 studies (341,281 participants), and the pooled prevalence of elevated blood pressure was 9.8% (95% CI 7.9, 11.9). The prevalence of elevated blood pressure in the obese children (34.1%, 95% CI 26.9, 41.7) and overweight children (15.5%, 95% CI 10.1, 21.7) was much higher than that in the normal or underweight children (5.0%, 95% CI 2.4, 8.4). Fluctuating trends in the prevalence of elevated blood pressure both in the total sample of Chinese children and adolescents and in each subgroup were observed from 2007 to 2014. Our study showed that prevalence of elevated blood pressure in children and adolescents in China was in the medium level in the world. Primary prevention for childhood hypertension should be implemented and focus on weight control and healthy lifestyle habits.

The synthesis, photophysics, and photobiological activities of a series of novel neutral heteroleptic cyclometalated iridium(iii) complexes incorporating boron dipyrromethene (BODIPY) substituted N-heterocyclic carbene (NHC) ligands (Ir1-Ir5) are reported. The effect of the substitution position of BODIPY on the NHC ligands, either on C4 of the phenyl ring (Ir1-Ir3) or C5 of the benzimidazole unit (Ir4 and Ir5), and its linker type (single or triple bond) on the photophysical properties was studied. Ir1-Ir5 exhibited BODIPY-localized intense 1IL (intraligand transition)/1MLCT (metal-to-ligand charge transfer) absorption at 530-543 nm and 1,3IL/1,3CT (charge transfer) emission at 582-610 nm. The nanosecond transient absorption results revealed that the lowest triplet excited states of these complexes were the BODIPY-localized 3π,π* states. Complexes Ir4 and Ir5 exhibited blue-shifted 1IL absorption and 1,3IL/1,3CT emission bands compared to the corresponding absorption and emission bands in complexes Ir1 and Ir3. However, replacing the methyl substituents on N3 of benzimidazole in complexes Ir1 and Ir4 with oligoether substituents in Ir3 and Ir5, respectively, did not impact the energies of the low-energy absorption and emission bands in the corresponding complexes. Water-soluble complexes Ir3 and Ir5 have been explored as photosensitizers for in vitro photodynamic therapy (PDT) effects toward human SKMEL28 melanoma cells. Ir3 showed no dark cytotoxicity (EC50 > 300 μM) but good photocytotoxic activity (9.66 ± 0.28 μM), whereas Ir5 exhibited a higher dark cytotoxicity (20.2 ± 1.26 μM) and excellent photocytotoxicity (0.15 ± 0.01 μM). The phototherapeutic indices with visible light (400-700 nm) activation were >31 for Ir3 and 135 for Ir5. Ir3 and Ir5 displayed 1O2 quantum yields of 38% and 22% in CH3CN, respectively, upon 450 nm excitation. Ir5 was more effective at generating reactive oxygen species (ROS) in vitro. Ir5 was also active against Staphylococcus aureus upon visible light activation, with a phototherapeutic index of >15 and EC50 value of 6.67 μM. These photobiological activities demonstrated that these neutral Ir(iii) complexes are promising in vitro PDT reagents, and substitution at C5 on the benzimidazole group of the NHC ligand was superior to C4 substitution on the phenyl ring.

Six homo- or heteroleptic tricationic Ir(R 1 -tpy)(R 2 -tpy) 3+ complexes ( Ir1 - Ir6 , R 1 /R 2 = Ph, 4'-N(CH 3 ) 2 Ph, pyren-1-yl, or 4'-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}Ph, tpy = 2,2';6',2"-terpyridine) were synthesized and tested for photodynamic therapy (PDT) effects. The ground- and excited-state characteristics of these complexes were studied systematically via spectroscopic methods and quantum chemistry calculations. All complexes possessed intraligand charge transfer ( 1 ILCT) / metal-to-ligand charge transfer ( 1 MLCT) dominated transition(s) in their low-energy absorption bands, which red-shifted with the increased electron-releasing strength of the R 1 /R 2 substituent. Five of the complexes exhibited ligand-centered 3 π,π */ 3 ILCT/ 3 MLCT emission. With a stronger electron-releasing R 1 /R 2 substituent, the degree of charge transfer contribution increased, leading to a decrease of the emission quantum yield. When the 4'-N(CH 3 ) 2 Ph substituent was introduced on both tpy ligands, the emission of Ir3 was completely quenched. Our study on the transient absorption of these complexes demonstrated that they all possessed broadband triplet excited-state absorption in the 400-800 nm region. Pyrenyl substitution of one or more tpy ligands, as in Ir4 and Ir5 , increased the lifetimes of the lowest triplet excited state and the singlet oxygen ( 1 O 2 ) production efficiencies. Ir1 - Ir5 were nontoxic toward SK-MEL-28 cells, with photocytotoxicities that varied from 0.18 to 153 µ M. Among them, Ir4 had the highest 1 O 2 quantum yield (0.81) in cell-free conditions, showing the largest photocytotoxicity against SK-MEL-28 cells for Ir(III) PSs to date, and was the most efficient generator of reactive oxygen species (ROS) in vitro . Ir4 possessed a very large phototherapeutic index (PI = dark EC 50 / light EC 50 ) of >1657, the largest reported for an Ir(III) complex photosensitizer upon broadband visible light (400-700 nm) activation. Ir4 also exhibited a very strong PDT effect toward MCF-7 breast cancer cells and its xenograft tumor model. Upon 450-nm light activation, Ir4 dramatically inhibited the xenograft tumor growth and exhibited negligible side effects upon PDT treatment., Competing Interests: Notes The authors declare no competing financial interest.

A series of cationic heteroleptic iridium(III) complexes bearing tris-diimine ligands [Ir(phen) 2 (R-phen)] 3+ (R-phen = phenanthroline (1), 3,8-diphenylphenanthroline (2), 3,8-dipyrenylphenanthroline (3), 3-phenylphenanthroline (4), 3-pyrenylphenanthroline (5), and 3,8-diphenylethynylphenanthroline (6)) were synthesized and characterized. These complexes possessed phen ligand-localized 1 π,π* transitions below 300 nm, and charge transfer ( 1 CT) and/or 1 π,π* transitions between 300 and 520 nm. In 1, 2, 4, and 6, the low-energy bands were mixed 1 CT/ 1 π,π*. However, the increased π-donating ability of the pyrenyl substituent(s) in 3 and 5 split the low-energy bands into a pyrene-based 1 π,π* transition at 300-380 nm and an intraligand charge transfer ( 1 ILCT) transition at 380-520 nm. All complexes were emissive at room temperature in CH 3 CN, but the parentage of the emitting state varied depending on the R substituent(s). Complex 1 exhibited predominantly phen ligand-localized 3 π,π* emission mixed with metal-to-ligand charge transfer ( 3 MLCT) character, whereas the emission of 2, 4, and 6 was predominantly from the excited-state with 3 π,π*/ 3 ILCT/ 3 MLCT character. The emission from 3 and 5 was dominated by pyrene-based 3 π,π* states mixed with 3 ILCT character. The different natures of the lowest triplet excited states were also reflected by the different spectral features and lifetimes of the triplet transient absorption of these complexes. Complexes 3 and 5 had singlet oxygen quantum yields as high as 81 and 72%, respectively. Both gave submicromolar phototoxicities toward cancer cells (SK-MEL-28 human melanoma) and bacteria ( S. aureus and S. mutans) with visible-light activation (and marginal to no photobiological activity with red light). Their visible-light phototherapeutic indices (PIs) toward SK-MEL-28 cells were 248 for 3 and >435 for 5; PIs were lower in bacteria (≤62) because of their inherent antimicrobial activities. Both complexes were shown to produce substantial amounts of intracellular reactive oxygen species (ROS), which may account for their photobiological activities.

Novel N6-coordinated Ir(iii) complexes bearing polypyridyl ligands were synthesized and characterized. In comparison to their Ru(ii) analogs, these Ir(iii) complexes showed blue-shifted UV-vis absorption and emission spectra, but dramatically increased triplet lifetimes with much broader and stronger triplet excited-state absorption.

Aims: Epidemiological studies of the long-term maternal health outcomes of spontaneous miscarriages have been sparse and inconsistent. The objective of our study is to examine the association between spontaneous miscarriages and diabetes among middle-aged and older Chinese women., Methods: A total of 19,539 women from the Dongfeng-Tongji cohort study who completed a questionnaire and had medical examinations performed on were included in the analysis. History of spontaneous miscarriage was obtained by self-reporting in the first follow-up questionnaire interview. The presence of diabetes was determined by a fasting plasma glucose level, self-reported physician diagnosis and use of antidiabetic medication. A series of multivariate logistic regression models were used to calculate the odds ratios and 95% CI across spontaneous miscarriage categories (0, 1, 2, ≥ 3) after adjustment for potential confounding factors., Results: The prevalence rate of diabetes was 18.8% among the participants. In the fully adjusted logistic regression model, women who had 1, 2 or ≥ 3 spontaneous miscarriages had 0.86 times (95% CI 0.68, 1.08), 1.30 times (95% CI 0.82, 2.04) and 2.11 times (95% CI 1.08, 4.11) higher risk of diabetes, respectively, compared with women who had no history of spontaneous miscarriage., Conclusions: There is an increased risk of diabetes among women with a history of a higher number of spontaneous miscarriages. History of multiple spontaneous miscarriages should be taken into consideration when assessing the risk of diabetes.

Objectives: Earlier age at natural menopause has been associated with cardiovascular disease in several studies, but evidence of its association with hypertension is lacking. We aimed to examine the relationship between age at natural menopause and hypertension among middle-aged and older Chinese women., Methods: A total of 13 406 postmenopausal women (mean age 63.5 years) were enrolled from the Dongfeng-Tongji cohort study in Hubei province, China. Age at natural menopause was self-reported and was categorized into three groups (≤45, 46-52, or ≥53 years). Logistic regression models were used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for hypertension in relation to age at natural menopause., Results: Of the study participants, 6690 (49.9%) women were diagnosed as hypertension. The mean age at natural menopause was 49.3 ± 3.3 years. After adjustment for potential confounders, the ORs of hypertension for women who reached menopause at age 45 or less and 46-52 years were 1.27 (95% CI, 1.08, 1.50) and 1.14 (95% CI, 1.01, 1.29), respectively, compared with those who reached menopause at age at least 53 years. Each 1-year delay in menopause was associated with 2% decrease in prevalence of hypertension (OR, 0.98; 95% CI, 0.97, 0.99)., Conclusion: Our findings suggested that earlier age at natural menopause was related to prevalence of hypertension independent of potential confounders. Identification of women with earlier menopause offers a window of opportunity to improve women's health during the postmenopausal years.

Background: Menopause is identified as a risk factor for cardiovascular disease because of the change of estrogen. The objective of the study was to explore the associations between early age at natural menopause (menopause at an age≤45years) and the presence of CHD and stroke., Methods: The study subjects were from the first follow-up survey of the Dongfeng-Tongji cohort study. A total of 16,515 postmenopausal women were included for the analysis. Logistic regression models were used to examine the associations between age at natural menopause (≤45, 45-52, >52years) and the presence of CHD and stroke adjusted for sociodemographic characteristics, lifestyle, reproductive history and metabolic factors., Results: In the fully adjusted model, for each 1-year delay in menopausal age, the prevalence of CHD and stroke was reduced by 3% (OR, 0.97; 95% CI, 0.95-0.98) and 5% (OR, 0.95; 95% CI, 0.92-0.98), respectively. Women with early menopause (≤45years) had a higher prevalence of CHD (OR, 1.33; 95% CI, 1.13-1.57) compared with those with menopause at ages 45-52years. Similarly, women with early menopause (≤45years) was associated with higher prevalence of stroke (OR, 1.69; 95% CI, 1.25-2.30) compared with those with menopause at ages 45-52years., Conclusions: Early age at natural menopause is significantly associated with the presence of CHD and stroke among Chinese women., (Copyright © 2017. Published by Elsevier B.V.)