Faganswanson6576
This is a short paper on new ways to think about the structure and function of small heat shock proteins (sHSPs), perhaps the most enigmatic family among protein chaperones. The goal is to incorporate new observations regarding the disordered regions of small heat shock proteins (sHSPs) into the large body of structural information on the conserved structural alpha-crystallin domains (ACD) that define the sHSP family. Disordered regions (N-terminal region and C-terminal region or NTR and CTR, respectively) represent over 50% of the sHSP sequence space in the human genome and are refractory to traditional structural biology approaches, posing a roadblock on the path towards a mechanistic understanding of how sHSPs function. A model in which an ACD dimer serves as a template that presents three grooves into which other proteins or other segments of sHSPs can bind is presented. Short segments within the disordered regions are observed to bind into the ACD grooves. There are more binding segments than there are grooves, and each binding event is weak and transient, creating a dynamic equilibrium of tethered and untethered disordered regions. The ability of an NTR to be in dynamic equilibrium between tethered/sequestered and untethered states suggests several mechanistic alternatives that need not be mutually exclusive. New ways of thinking about (and approaching) the intrinsic properties of sHSPs may finally allow the veil of enigma to be removed from sHSPs.INTRODUCTION The current treatment concepts of fracture-related infection (FRI) [Consensus Conference (Anti-Infection Task Force (AITF)) on the definition of acute or chronic osteomyelitis (cOM)] are associated with unsolved challenges and problems, underlining the need for ongoing medical research. METHOD Literature review of treatments for FRI and description of own cases. RESULTS We could include eight papers with 394 patients reporting treatments and outcome in FRI. The infection was resolved in 92.9% (mean) of all treatments. The mean follow-up was 25 months with a persistent non-union in 7% of the patients. We diagnosed 35 (19f/16m; 56.4 ± 18.6 years) patients with bone infections anatomically allocated to the proximal and distal femur (12×), the pelvis (2×), distal tibia (3×), tibial diaphysis (11×), the ankle joint (4×) and calcaneus (3×). These 35 patients were treated (1) with surgical debridement; (2) with antibiotic-eluting ceramic bone substitutes; (3) bone stabilization (including nail fixation, arthrodesis nails, plates, or external ring fixation), (4) optionally negative pressure wound therapy (NPWT) and (5) optionally soft tissue closure with local or free flaps. The mean follow-up time was 14.9 ± 10.6 months (min/max 2/40 month). The overall recurrence rate is low (8.5%, 3/35). Motolimod solubility dmso Prolonged wound secretion was observed in six cases (17.1%, 6/35). The overall number of surgeries was a median of 2.5. CONCLUSION The results in the literature and in our case series are explicitly promising regarding the treatment of posttraumatic fracture-related infection.BACKGROUND AND OBJECTIVES Imeglimin (IMEG) is the first in a novel class of oral glucose-lowering agents with a unique mechanism of action targeting mitochondrial bioenergetics. We assessed whether repeated co-administration of IMEG and either metformin (MET) or sitagliptin (SITA) would influence the pharmacokinetics of either MET or SITA in healthy Caucasian men. METHODS Healthy Caucasian men received either MET 850 mg twice daily with placebo (n = 16) or SITA 100 mg once daily with placebo (n = 16) on days 1-6, followed by MET 850 mg twice daily with IMEG 1500 mg twice daily or SITA 100 mg once daily with IMEG 1500 mg twice daily on days 7-12. Pharmacokinetic parameters were determined from blood and urine; levels of all compounds were evaluated using liquid chromatography with tandem mass spectrometry. RESULTS Systemic exposure (AUC0-τ area under the plasma concentration-time curve over a dosing interval and maximum concentration) to MET was 14% and 10% lower, respectively, when administered with IMEG. Approximately 40% of MET was excreted unchanged in urine, decreasing to 34% when given with IMEG. The 90% confidence intervals for AUC0-τ and maximum concentration indicated no effect of co-administration on systemic exposure to MET. Mean AUC0-τ and maximum concentration of SITA were similar with or without IMEG. Median times to maximum concentration were 0.7 and 1.0 h and mean elimination half-lives were 8.2 and 8.7 h with and without IMEG, respectively. Systemic exposure to IMEG was similar to previous phase I studies. CONCLUSIONS Co-administration of IMEG with MET or SITA did not result in clinically relevant changes in systemic exposure to MET or SITA, although minor reductions in exposure (AUC0-τ and maximum concentration) and renal elimination were noted when MET was given with IMEG vs placebo. CLINICAL TRIAL REGISTRATION EudraCT2009-014520-40 (MET-IMEG DDI) and EudraCT2010-022926-34 (SITA-IMEG DDI).Statins, widely prescribed for cardiovascular diseases, are also being eyed for management of age-related macular degeneration (AMD). Poor bioavailability and blood-aqueous barrier may however limit significant ocular concentration of statins following oral administration. We for the first time propose and investigate local application of atorvastatin (ATS; representative statin) loaded into solid lipid nanoparticles (SLNs), as self-administrable eye drops. Insolubility, instability, and high molecular weight > 500 of ATS, and ensuring that SLNs reach posterior eye were the challenges to be met. ATS-SLNs, developed (2339/DEL/2014) using suitable components, quality-by-design (QBD) approach, and scalable hot high-pressure homogenization, were characterized and evaluated comprehensively for ocular suitability. ATS-SLNs were 8 and 12 times more bioavailable (AUC) in aqueous and vitreous humor, respectively, than free ATS. Three-tier (in vitro, ex vivo, and in vivo) ocular safety, higher corneal flux (2.5-fold), and improved stability (13.62 times) including photostability of ATS on incorporation in ATS-SLNs were established. Autoclavability and aqueous nature are the other highlights of ATS-SLNs. Presence of intact fluorescein-labeled SLNs (F-SLNs) in internal eye tissues post-in vivo application as eye drops provides direct evidence of successful delivery. Perinuclear fluorescence in ARPE-19 cells confirms the effective uptake of F-SLNs. Prolonged residence, up to 7 h, was attributed to the mucus-penetrating nature of ATS-SLNs. Graphical abstract.