Photoinduced Energy and Electron-Transfer Reactions by Polypyridine Ruthenium(II) Complexes Containing a Derivatized Perylene Diimide

The [Ru­(II) (phen)₂(pPDIp)]²⁺ complex, where pPDIp is the symmetric bridging ligand phenanthroline–perylene–phenanthroline, shows strong electronic absorption bands attributed to the pPDIp and {Ru­(phen)₂}²⁺ moieties in acetonitrile. The charge-separated intermediate {Ru­(III) (phen)₂(pPDIp^–•)} was detected by transient absorption spectroscopy upon electronic excitation in either the pPDIp or the complex moieties. The charge-separated intermediate species decays to generate the triplet state ³*pPDIp-Ru­(II) (τ_P = 1.8 μs) that sensitizes the formation of singlet molecular oxygen with quantum yield ϕ_Δ = 0.57. The dyad in deaerated acetonitrile solutions is reduced by triethylamine (NEt₃) to the [Ru­(II) (phen)₂(pPDIp^•–)] radical anion in the dark. The electron-transfer reaction is accelerated by light absorption. By photolysis of the radical anion, a second electron transfer reaction occurs to generate the [Ru­(II) (phen)₂(pPDIp^2–)] dianion. The changes of the color of solution indicate the redox states of complexes and offer a sensitive reporter of each stage of redox reaction from start to finish. The reduced complexes can be converted to the initial complex, using methyl viologen or molecular oxygen as an electron acceptor. The accumulation of electrons in two well-separated steps opens promising opportunities such as in catalysis

Thermodynamic Study of Methylene Blue Adsorption on Carbon Nanotubes Using Isothermal Titration Calorimetry: A Simple and Rigorous Approach

In this article, a thermodynamic study of the methylene blue (MB) adsorption on carbon nanotubes (CNT), a known model system, was carried out by using a simple and rigorous experimental approach based on adsorption and isothermal titration calorimetry (ITC) experiments. Considering the thermodynamics of the process, the classical approach using the van’t Hoff approximation provided endothermic values for Δ_ads<i>H</i>⁰ while the ITC measurements revealed that the adsorption of MB on both unmodified and acid-modified CNTs is an exothermic process. The thermodynamic parameters for the systems were obtained using the infinite dilution regime and ITC data: Δ_ads<i>H</i>⁰ = −9.13 ± 0.02 kJ mol^–1, Δ_ads<i>G</i>⁰ = −21.18 ± 0.61 kJ mol^–1, and Δ_ads<i>S</i>⁰ = 40.42 ± 0.61 J K^–1 mol^–1 for u-CNT and Δ_ads<i>H</i>⁰ = −11.49 ± 0.34 kJ mol^–1, Δ_ads<i>G</i>⁰ = −27.88 ± 0.18 kJ mol^–1, and Δ_ads<i>S</i>⁰ = 54.97 ± 0.38 J K^–1 mol^–1 for f-CNT. The process is both enthalpically and entropically driven, having a more negative Δ_ads<i>G</i>⁰ for the system based on a modified nanotube. With this work, we expect to increase the interest of researchers in the study of other solid–liquid adsorption systems using calorimetric techniques and also contribute to a more accurate characterization of the thermodynamic properties without the use of an excessive number of approximations

Kidney and Cardiovascular Effects of Canagliflozin According to Age and Sex: A Post Hoc Analysis of the CREDENCE Randomized Clinical Trial

Rationale &amp; Objective: It is unclear whether the effect of canagliflozin on adverse kidney and cardiovascular events in those with diabetic kid-ney disease varies by age and sex. We assessed the effects of canagliflozin among age group categories and between sexes in the Canagli-flozin and Renal Endpoints in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) study.Study Design: Secondary analysis of a random-ized controlled trial. Setting &amp; Participants: Participants in the CREDENCE trial. Intervention: Participants were randomly assigned to receive canagliflozin 100 mg/d or placebo.Outcomes: Primary composite outcome of kid-ney failure, doubling of serum creatinine con-centration, or death due to kidney or cardiovascular disease. Prespecified secondary and safety outcomes were also analyzed. Out-comes were evaluated by age at baseline (&lt;60, 60-69, and &gt;_70 years) and sex in the intention-to-treat population using Cox regression models.Results: The mean age of the cohort was 63.0 &amp; PLUSMN; 9.2 years, and 34% were female. Older age and female sex were independently associ-ated with a lower risk of the composite of adverse kidney outcomes. There was no evidence that the effect of canagliflozin on the primary outcome (acomposite of kidney failure, a doubling of serum creatinine concentration, or death from kidney or cardiovascular causes) differed between age groups (HRs, 0.67 [95% CI, 0.52-0.87], 0.63 [0.4 8-0.82], and 0.89 [0.61-1.29] for ages &lt;60, 60-69, and &gt;_70 years, respectively; P = 0.3 for interaction) or sexes (HRs, 0.71 [95% CI, 0.5 4-0.95] and 0.69 [0.56-0.8 4] in women and men, respectively; P = 0.8 for interaction). No differences in safety outcomes by age group or sex were observed.Limitations: This was a post hoc analysis with multiple comparisons.Conclusions: Canagliflozin consistently reduced the relative risk of kidney events in people with diabetic kidney disease in both sexes and across age subgroups. As a result of greater background risk, the absolute reduction in adverse kidney outcomes was greater in younger participants.Funding: This post hoc analysis of the CREDENCE trial was not funded. The CREDENCE study was sponsored by Janssen Research and Development and was conducted collaboratively by the sponsor, an academic-led steering committee, and an academic research organization, George Clinical.Trial Registration: The original CREDENCE trial was registered at ClinicalTrials.gov with study number NCT02065791

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Background Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien-Dindo classification system. Results A total of 3288 patients were included in the analysis, of whom 301 (9 center dot 2 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4-7) and 7 (6-8) days respectively (P &lt; 0 center dot 001). There were no significant differences in rates of readmission between these groups (6 center dot 6 versus 8 center dot 0 per cent; P = 0 center dot 499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0 center dot 90, 95 per cent c.i. 0 center dot 55 to 1 center dot 46; P = 0 center dot 659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34 center dot 7 versus 39 center dot 5 per cent; major 3 center dot 3 versus 3 center dot 4 per cent; P = 0 center dot 110). Conclusion Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients