The identification of the UV degradants of melatonin and their ability to scavenge free radicals

Ultraviolet (UV) light is known to induce the generation of free radicals in biological tissues such as skin. Of these free radicals, the O2-. and particularly the.OH radical can induce cellular damage including lipid peroxidation. Thus, the use of antioxidants to prevent such damage induced by UV irradiation has received much attention recently. One such antioxidant, which has the potential to be incorporated into sunscreens, is the pineal secretory product melatonin. One of the concerns of using melatonin in sunscreens is its photostability. In the present study, we investigated the photostability of melatonin subjected to UV irradiation. In addition, we used liquid chromatography mass spectrometry (LC-MS) to identify the degradants and we also assessed the ability of the degradants to inhibit O2-. generation as well as lipid peroxidation in rat brain homogenate. The results show that UV irradiation of melatonin (0.1 mg/mL) using a 400-W lamp for 2 hr caused a significant decline of melatonin to 18% of its original concentration after 20 min, with the decline continuing until the melatonin concentration reaches zero at 120 min. The LC-MS results show that the degradants of melatonin are 6-hydroxymelatonin and N1-acetyl-N2-formyl-5-methoxykynurenamine (AFMK). These degradants were able to provide equipotent activity against potassium cyanide (KCN)-induced superoxide generation compared to non-irradiated melatonin. Thus, the study shows that although melatonin is rapidly degraded by UV irradiation, the degradants retain antioxidant activity, making melatonin a likely candidate for inclusion in sunscreens.     

Therapeutic Benefit and Gene Network Regulation by Combined Gene Transfer of Apelin,FGF2, and SERCA2a into Ischemic Heart

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Safety,Tolerability, and Pharmacokinetics of Single and Repeat Doses of Nemiralisib Administered via the Ellipta Dry Powder Inhaler to Healthy Subjects

Purpose

Novel therapies to treat chronic obstructive pulmonary disease are highly desirable. The safety, tolerability, and pharmacokinetic (PK) parameters of nemiralisib, a phosphoinositide 3-kinase δ inhibitor, administered via the Ellipta dry powder inhaler (GlaxoSmithKline, Research Triangle Park, North Carolina) was evaluated, including an assessment of oral bioavailability.

HIV Sexual Risk and Syndemics among Women in Three Urban Areas in the United States: Analysis from HVTN 906

Limited data are available on the longitudinal occurrence of syndemic factors among women at risk for HIV infection in the USA and how these factors relate to sexual risk over time. HVTN 906 was a longitudinal study enrolling 799 HIV-uninfected women in three cities. Assessments were done at baseline, 6, 12, and 18 months to assess syndemic factors (low education, low income, unemployment, lack of health insurance, housing instability, substance use, heavy alcohol use, partner violence, incarceration) and sexual risk outcomes. For each sexual risk outcome, a GEE model was fit with syndemic factors or syndemic score (defined as sum of binary syndemics, ranging from 0 to 9), visit, study site, age and race/ethnicity as predictors to examine the multivariable association between syndemic factors and outcomes over time. Odds of unprotected sex while drunk or high were significantly higher when women reported lack of health insurance, substance and heavy alcohol use and partner violence. Housing instability, substance and heavy alcohol use, partner violence and recent incarceration were associated with higher odds of having multiple sexual partners. Odds of sex exchange were significantly higher in the presence of unemployment, housing instability, low education, lack of health insurance, substance and heavy alcohol use, partner violence and incarceration. Housing instability, substance and heavy alcohol use, and partner violence were significantly associated with higher odds of unprotected anal sex. Odds of having a recent STI were significantly higher when women reported housing instability and partner violence. There were significantly higher odds of the reporting of any risk outcomes during follow-up with higher syndemic score. This study highlights a group of women experiencing multiple poor social and health outcomes who need to be the focus of comprehensive interventions.     

Former uranium mine-induced effects in caged roach: a multiparametric approach for the evaluation of in situ metal toxicity

Ecotoxicology - To characterize environmental risks linked to former uranium mines in the Limousin region of France, a study was conducted on fish health effects from uranium releases. Two private...     

Clinical presentations and outcomes in pulmonary embolism patients with cancer

Journal of Thrombosis and Thrombolysis - To study whether a diagnosis of cancer affects the clinical presentation and outcomes of patients with pulmonary embolism (PE). A retrospective analysis was...