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61.
In the past, intercellular penetration was assumed to be the most important penetration pathway of topically applied substances. First hints that follicular penetration needs to be taken into consideration were confirmed by recent investigations, presented during the workshop "Follicular Penetration and Targeting" at the 4th Intercontinental Meeting of Hair Research Societies", in Berlin 2004. Hair follicles represent an efficient reservoir for the penetration of topically applied substances with subsequent targeting of distinct cell populations, e.g., nestin-expressing follicular bulge cells. The volume of this reservoir can be determined by differential stripping technology. The follicular penetration processes are significantly influenced by the state of the follicular infundibulum; recent experimental investigations could demonstrate that it is essential to distinguish between open and closed hair follicles. Topically applied substances can only penetrate into open hair follicle. Knowledge of follicular penetration is of high clinical relevance for functional targeting of distinct follicular regions. Human hair follicles show a hair-cycle-dependent variation of the dense neuronal and vascular network. Moreover, during hair follicle cycling with initiation of anagen, newly formed vessels occur. Thus, the potential of nestin-expressing hair follicle stem cells to form neurons and blood vessels was investigated.  相似文献   
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Dermal dendritic cells (DCs) play a central role in the immunopathology of psoriasis. We previously identified slanDCs as pro‐inflammatory TNF‐α, IL‐23‐ and IL‐12‐producing DCs in human blood and as prominent inflammatory dermal TNF‐α secreting and CD11c‐positive DC subset in psoriasis. Here, we ask for the effects of TNF‐α‐inhibition on inflammatory slanDCs in skin and blood of 10 patients with psoriasis during 24 weeks of treatment with etanercept. Treatment with etanercept reduced the frequency of dermal slanDCs but did not induce apoptosis as determined by lack of increased active caspase‐3‐expression. In parallel, we found increased frequencies of slanDCs in blood which expressed lower levels of HLA‐DR. Stimulating slanDCs isolated from the blood of healthy donors in vitro induced a strong production of IL‐1β, IL‐6, IL‐23 and IL‐12p70. This capacity was efficiently reduced in the presence of etanercept, thereby indicating that TNF‐α is an autocrine stimulus for maturation and pro‐inflammatory cytokine production of slanDCs. In vivo, we noticed that treatment with etanercept did reduce the number of dermal slanDCs in parallel to the overall expression of TNF‐α and IL‐23p19. However, successful treatment did not down‐regulated the percentage of dermal slanDCs that stained positive for TNF‐α and IL‐23p19 indicating that remaining slanDCs kept their pro‐inflammatory capacity. This study provides novel insights into the immune regulatory properties of etanercept at the level of inflammatory slanDCs in vivo in skin and blood as well as in vitro.  相似文献   
63.
We investigated the effects of viral infection on Tissue Factor (TF) expression and activity in mice within the myocardium to understand increased thrombosis during myocarditis. Mice were infected with coxsackie virus B3 (CVB3) and the hearts were collected at day 4, 8 and 28 post infection (p.i.). Myocardial TF expression and cellular activity as well as plasma activity were analyzed from CVB3 infected mice by Western blot, chromogenic Factor Xa generation assay, in situ staining for active TF and immunohistochemistry. In addition to TF expression, hemodynamic parameters were measured during the time course of infection. Furthermore, we analyzed myocardial tissues from patients with suspected inflammatory cardiomyopathy. TF protein expression was maximally 5-fold elevated 8 days p.i. in mice and remained increased on day 28 p.i. (P < 0.001 vs. non-infected controls). Alterations in TF expression were associated with fibrin deposits within the myocardium. The TF pathway inhibitor protein expression in the myocardium was not altered during myocarditis. Active cellular TF co-localized with CD3 positive cells and VCAM-1 positive endothelial cells in the myocardium. The TF expression was positively correlated with the amount of infiltrating CD3 and Mac3 positive cells (Spearman-Rho ρ = 0.749 P < 0.0001 for CD3+ and ρ = 0.775 P < 0.0001 for Mac3+; N = 35). Increased myocardial TF expression was associated with a 2-fold elevated plasma activity (P < 0.05 vs. non-infected controls). In the human hearts, the TF expression correlated postively with an endothelial cell activation marker (ρ = 0.523 P < 0.0001 for CD62E; N = 54). Viral myocarditis is a hypercoagulative state which is associated with increased myocardial TF expression and activity. Upregulation of TF contributes to a systemic activation of the coagulation cascade.  相似文献   
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The aim of the study was to assess the quantity and nature of emergencies affecting adults with congenital cardiac disease (CCD) and evaluate infrastructural requirements for adequate management. There is an increasing number of adults with CCD requiring specialized complex care. This multicenter study evaluated all emergency admissions to 1 of 5 centers for adults with CCD within 1 year. Within 1 year, there were 1,033 admissions of adults with CCD, and 201 (160 patients; age 16 to 71 years) were emergencies. Underlying cardiac anomalies were univentricular heart (22%), complete transposition (14%), tetralogy of Fallot (21%), and others (43%). Seventy percent of patients had undergone previous cardiac surgery. The main reason for acute admission was cardiovascular (arrhythmia, heart failure, syncope, aortic dissection, and endocarditis). Diagnostic procedures most often assigned were echocardiography (n = 223), chest x-ray (n = 95), Holter electrocardiography (n = 85), cardiac catheterization/electrophysiologic study (n = 39), and others (n = 143). Forty-six patients underwent surgery (cardiovascular n = 41, general n = 5) or electrophysiologic treatment (n = 41). One hundred twenty-six of 201 emergencies (63%) required cooperation with another specialized department: surgery (n = 46), internal medicine (n = 42), neurology (n = 12), ophthalmology (n = 6), otorhinolaryngology (n = 5), gynecology (n = 5), psychiatry (n = 4), radiology (n = 3), dermatology (n = 2), and orthopedics (n = 2). In conclusion, physicians and consultants attending adult patients with CCD need a high degree of specialized experience concerning the cardiac anomaly to manage emergencies properly. Furthermore, a wide range of noncardiac diagnostic and therapeutic procedures must be available. Data support the demand for a multidisciplinary approach in specialized centers for adequate care of adults with CCD.  相似文献   
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Herein we report the copolymerization of CHO with CO2 in the presence of various zinc compounds R2Zn (R = Et, Bu, iPr, Cy and Ph). Several zinc organyls proved to be efficient catalysts for this reaction in the absence of water and co-catalyst. Notably, readily available Bu2Zn reached a TON up to 269 and an initial TOF up to 91 h−1. The effect of various parameters on the reaction outcome has been investigated. Poly(ether)carbonates with molecular weights up to 79.3 kg mol−1 and a CO2 content of up to 97% were obtained. Under standard reaction conditions (100 °C, 2.0 MPa, 16 h) the influence of commonly employed co-catalysts such as PPNCl and TBAB has been investigated in the presence of Et2Zn (0.5 mol%). The reaction of other epoxides (e.g. propylene and styrene oxide) under these conditions led to no significant conversion or to the formation of the respective cyclic carbonate as the main product.

Simple zinc organyls (R2Zn) efficiently catalyze the copolymerization of CO2 and cyclohexene oxide. The effect of various reaction parameters has been studied. The reaction proceeds under halogen-free conditions and no co-catalyst is required.  相似文献   
69.

Background

Venous thromboembolism (VTE) is a relatively rare condition in childhood with treatment mainly based on extrapolation from studies in adults. Therefore, clinical trials of anticoagulation in children require novel approaches to deal with numerous challenges. The EINSTEIN-Jr program identified pediatric rivaroxaban regimens commencing with in vitro dose finding studies followed by evaluation of children of different ages through phase I and II studies using extensive modeling to determine bodyweight-related doses. Use of this approach resulted in drug exposure similar to that observed in young adults treated with rivaroxaban 20?mg once-daily.

Methods

EINSTEIN-Jr phase III is a randomized, open-label, study comparing the efficacy and safety of rivaroxaban 20?mg-equivalent dose regimens with those of standard anticoagulation for the treatment of any types of acute VTE in children aged 0–18?years.A total of approximately 500 children are expected to be included during the 4-year study window. Flexibility of treatment duration is allowed with study treatment to be given for 3?months with the option to continue treatment in 3-month increments, up to a total of 12?months. However, based on most common current practice, children younger than 2?years with catheter-related thrombosis will have a main treatment period of 1?month with the option to prolong treatment in 1-month increments, up to a total of 3?months.

Conclusions

EINSTEIN-Jr will compare previously established 20?mg-equivalent rivaroxaban dosing regimens with standard anticoagulation for the treatment of VTE in children. Demonstration of similarity of disease, as well as equivalent rivaroxaban exposure and exposure-response will enable extrapolation of efficacy from adult trials, which is critical given the challenges of enrollment in pediatric anticoagulation trials.

Trial registration

Clinicaltrials.gov NCT02234843, registered on 9 September 2014.
  相似文献   
70.
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