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Lake Hammond posted an update 2 days, 19 hours ago
The skin is essential for terrestrial life. It is responsible for regulating water permeability and functions as a mechanical barrier that protects against environmental insults, such as microbial infection, ultraviolet light, injury and heat and cold, which could damage the cells of the body and compromise survival of the organism. This barrier is provided by the outer layer, the epidermis, which is composed predominantly of keratinocytes; keratinocytes undergo a program of differentiation to form the stratum corneum comprising the cornified squame “bricks” and lipid “mortar”. Dysregulation of this differentiation program can result in skin diseases, including psoriasis and non-melanoma skin cancers, among others. Accumulating evidence in the literature indicates that the water-, glycerol- and hydrogen peroxide-transporting channel aquaporin-3 (AQP3) plays a key role in various processes involved in keratinocyte function, and abnormalities in this channel have been observed in several human skin diseases. Here we discuss the data linking AQP3 to keratinocyte proliferation, migration, differentiation and survival as well as its role in skin properties and functions like hydration, water retention, wound healing, and barrier repair. We also discuss the mechanisms regulating AQP3 levels, localization, and function and the anomalies in AQP3 that are associated with various skin diseases.Essential hypertension is associated with impairments in vascular function and sympathetic nerve hyperactivity; however, the extent to which the lower limbs are affected remains unclear. We examined the leg vascular responsiveness to infusion of acetylcholine (ACh), sodium nitroprusside (SNP) and phenylephrine (PEP) in ten hypertensive men (HYP age 59.5±9.7 (mean±SD) years, clinical and night-time blood pressure 142±10/86±10 and 141±11/83±6 mmHg, respectively, BMI 29.2±4.0 kg∙m-2) and 8 age-matched normotensive counterparts (NORM age 57.9±10.8 years, clinical and night-time blood pressure 128±9/78±7 and 116±3/69±3 mmHg, respectively, BMI 26.3±3.1 kg∙m-2). The vascular responsiveness was evaluated before and after 6 weeks of 10-20-30 training, consisting of 3x 5×10-s sprint followed by 30 and 20 s of low- to moderate-intensity cycling, respectively, interspersed by 3 min of rest. Before training, the vascular responsiveness to infusion of SNP was lower (P less then 0.05) in HYP compared to NORM, with no difference in the responsiveness to infusion of ACh and PEP. The vascular responsiveness to infusion of SNP and ACh improved (P less then 0.05) with training in HYP, with no change in NORM. With training, intra-arterial systolic blood pressure decreased (P less then 0.05) by 9 mmHg in both HYP and NORM whereas diastolic blood pressure decreased (5 mmHg; P less then 0.05) in HYP only. We provide here the first line of evidence in humans that smooth muscle cell vasodilator responsiveness is blunted in the lower limbs of hypertensive men. This impairment can be reversed by 10-20-30 training, which is an effective intervention to improve the responsiveness of smooth muscle cells in men with essential hypertension.The objective of the current investigation was to develop a simple, rapid, and stability-indicating high-performance liquid chromatography method and to study the degradation behavior of sulfapyridine (SP) under different International Conference on Harmonization (ICH)-recommended conditions. The chromatographic method was developed using C18 (250 × 4.6 mm, 5 μ) column, and mobile phase consisting of acetonitrile-0.1% formic acid (3070 v/v) at ambient temperature, at a flow rate of 1 mL/min. The elution was monitored at 265 nm using a photodiode array detector. The developed method was subsequently validated as per ICH Q2 (R1) guidelines. The retention time of SP was observed as 4.56 min with the linearity range between 2 to 10 μg/mL. Vorinostat chemical structure Limit of detection and limit of quantitation for SP were 0.115 and 0.35 μg/mL, respectively. Forced degradation studies were carried out on bulk samples of SP using prescribed acidic, basic, oxidative, thermal, and photolytic conditions. Extent of degradation in 0.1 M hydrochloric acid and under photolytic conditions was found to be 21.56% and 28.57%, respectively. The degradation products formed in stress conditions were identified by liquid chromatography-mass spectrometry (LC-MS). The utility of the method was verified by quantification of SP in different laboratory-made pharmaceutical preparations. The proposed method could be successfully used to quantify SP in different pharmaceutical dosage forms.To exploit the high-temperature superinsulation potential of anisotropic thermal management materials, the incorporation of ceramic aerogel into the aligned structural networks is indispensable. However, the long-standing obstacle to exploring ultralight superinsulation ceramic aerogels is the inaccessibility of its mechanical elasticity, stability, and anisotropic thermal insulation. In this study, we report a recoverable, flexible ceramic fiber-aerogel composite with anisotropic lamellar structure, where the interfacial cross-linking between ceramic fiber and aerogel is important in its superinsulation performance. The resulting ultralight aerogel composite exhibits a density of 0.05 g/cm3, large strain recovery (over 50%), and low thermal conductivity (0.0224 W m-1 K-1), while its hydrophobicity is achieved by in situ trichlorosilane coating with the water contact angle of 135°. The hygroscopic tests of such aerogel composites demonstrate a reversible thermal insulation. The mechanical elasticity and stability of the anisotropic composites, with its soundproof performance, shed light on the low-cost superelastic aerogel manufacturing with scalability for energy saving building applications.Antibody-coupled photosensitive molecules can achieve an ideal tumor-specific photodynamic therapy (PDT) and show strong clinical application potential. However, some inherent disadvantages, such as long circulation half-life, poor permeation into solid tumors, and difficulty in obtaining uniform coupling products, present potential problems to clinical applications. In this study, we propose a novel design of targeting photosensitizers, based on a very small targeting protein (an affibody molecule) coupled with photosensitive compounds, to address these problems. In the synthesis, photosensitive pyropheophorbide-a (Pyro) is modified with a PEG linker (molecular weight of 727 Da) and then site specifically coupled to the anti-HER2 ZHER22891 affibody protein to provide a homogeneous protein-coupled photosensitizer via a convenient process. In vitro and in vivo experiments show that this molecule has an ideal selectivity for binding and photocytotoxicity against HER2-positive cells (more than 50-fold selectivity between HER2-high expression and HER2-low expression cells) and highly specific tumor accumulation; at a relatively low dose, it effectively eliminated HER2-high expression NCI-N87 tumors in a mouse model.