The long periodicity phase (LPP) controversy part I: The influence of a natural-like ratio of the CER[EOS] analogue [EOS]-br in a CER[NP]/[AP] based stratum corneum modelling system: A neutron diffraction study

This study used neutron diffraction to investigate a ceramide-[NP] C24/[AP] C24 /[EOS]-br C30/cholesterol/lignoceric acid (0.6: 0.3: 0.1: 0.7: 1) based stratum corneum modelling system. By adding specifically deuterated ceramides-[NP]-D₃, [AP]-D₃, and [EOS]-br-D₃, detailed information on the lamellar and the nanostructure of the system was obtained. For the short periodicity phase a natural-like lamellar repeat distance of 5.47?±?0.02?nm was observed, similar to the [NP]/[AP] base system without the [EOS]-br. Unlike in this system the ceramides here were slightly tilted, hinting towards a slightly less natural arrangement. Due to the deuteration it was possible to observe that the long ceramide chains were overlapping in the lamellar mid-plane. This is considered to be an important feature for the natural stratum corneum. Despite the presence of a ceramide [EOS] analogue – able to form a long phase arrangement – no distinct long periodicity phase was formed, despite a slightly higher than natural ω-acyl ceramide ratio of 10?mol%. The deuterated variant of this ceramide determined that the very long ceramide was integrated into the short periodicity phase, spanning multiple layers instead. The – compared to the base system – unchanged repeat distance highlights the stability of this structure. Furthermore, the localisation of the very long ceramide in the short periodicity phase indicates the possibility of a crosslinking effect and thus a multilayer stabilizing role for the ceramide [EOS]. It can be concluded, that additionally to the mere presence of ceramide-[EOS] more complex conditions have to be met in order to form this long phase. This has to be further investigated in the future.     

Blau syndrome polymorphisms in NOD2 identify nucleotide hydrolysis and helical domain 1 as signalling regulators

Understanding how single nucleotide polymorphisms (SNPs) lead to disease at a molecular level provides a starting point for improved therapeutic intervention. SNPs in the innate immune receptor nucleotide oligomerisation domain 2 (NOD2) can cause the inflammatory disorders Blau Syndrome (BS) and early onset sarcoidosis (EOS) through receptor hyperactivation. Here, we show that these polymorphisms cluster into two primary locations: the ATP/Mg²⁺-binding site and helical domain 1. Polymorphisms in these two locations may consequently dysregulate ATP hydrolysis and NOD2 autoinhibition, respectively. Complementary mutations in NOD1 did not mirror the NOD2 phenotype, which indicates that NOD1 and NOD2 are activated and regulated by distinct methods.     

Hymenolepis diminuta: Effect of infection on ion transport in colon and blood picture of rats

The aim of this study was to examine the effect of an infection with Hymenolepis diminuta on ion transport in an isolated colon and blood picture of rats. Fifty rats were orally infected with five cysticercoids of H. diminuta. The experimental groups of rats were assigned to four groups: group I - 8 days post-infection (dpi), group II - 16 dpi, group III - 40 dpi and group IV- 60 dpi. The control group comprised non-infected rats. The experiments consisted of measuring the transepithelial electrical potential difference (PD) and the transepithelial electrical resistance (R) of the rat colon under controlled conditions as well as during mechanical stimulation (MS) using a modified Ussing chamber. Ion transport was modified using inhibitors of the epithelial sodium channel (amiloride - AMI) and the epithelial chloride channel (bumetanide - BUME), and also using capsaicin (CAPSA), a substance which activates C-fibres. The experimental data presented in this study indicates that experimental hymenolepidosis inhibits sodium and chloride ion transport in the epithelium of the rat colon, with preserved tight junction continuity (except at 40 dpi) and a decreased mechanical sensitivity. The effect of capsaicin on ion transport in the rat colon was varied. In control rats it increased ionic current, and in H. diminuta-infected rats it did not cause any changes in PD.Blood picture in this study showed a statistically significantly lower red blood cells (RBC) count and haemoglobin (HGB) concentration in infected rats in comparison to non-infected. Red cell distribution width (RDW) values and platelet (PLT) count were negatively correlated with the duration of infection, whereas mean corpuscular volume (MCV) value was positively correlated. We did not observe leukocytosis during infection, and amongst the differential leukocyte counts eosinophils and basophils showed statistically significant lower values in infected rats in comparison to non-infected.Our results indicate that hymenolepidosis is associated with the activation of inflammatory mediators and stimulation of nervous fibres, which significantly affects the function of ion channels in the epithelium of the colon in the host. At the same time, a significant decrease in eosinophil count during infection suggests that such an infection did not trigger a strong immunological reaction in rats.     

Comparison of rat epidermal keratinocyte organotypic culture (ROC) with intact human skin: Lipid composition and thermal phase behavior of the stratum corneum

The present report is a part of our continuing efforts to explore the utility of the rat epidermal keratinocyte organotypic culture (ROC) as an alternative model to human skin in transdermal drug delivery and skin irritation studies of new chemical entities and formulations. The aim of the present study was to compare the stratum corneum lipid content of ROC with the corresponding material from human skin. The lipid composition was determined by thin-layer chromatography (TLC) and mass-spectrometry, and the thermal phase transitions of stratum corneum were studied by differential scanning calorimetry (DSC). All major lipid classes of the stratum corneum were present in ROC in a similar ratio as found in human stratum corneum. Compared to human skin, the level of non-hydroxyacid-sphingosine ceramide (NS) was increased in ROC, while α-hydroxyacid-phytosphingosine ceramide (AP) and non-hydroxyacid-phytosphingosine ceramides (NP) were absent. Also some alterations in fatty acid profiles of ROC ceramides were noted, e.g., esterified ω-hydroxyacid-sphingosine contained increased levels of oleic acid instead of linoleic acid. The fraction of lipids covalently bound to corneocyte proteins was distinctly lower in ROC compared to human skin, in agreement with the results from DSC. ROC underwent a lipid lamellar order to disorder transition (T₂) at a slightly lower temperature (68 °C) than human skin (74 °C). These differences in stratum corneum lipid composition and the thermal phase transitions may explain the minor differences previously observed in drug permeation between ROC and human skin.     

孟鲁司特钠联合布地奈德混悬液对哮喘急性发作患儿血清EOS、ECP水平和肺功能的影响

目的:探索孟鲁司特钠联合布地奈德混悬液对哮喘急性发作患儿血清嗜酸性粒细胞(EOS)、嗜酸性粒细胞阳离子蛋白(ECP)水平和肺功能的影响。方法:选择自2015年10月至2016年10月我院收治的200例支气管哮喘急性发作患儿,按照随机数表法分成观察组和对照组各100例。对照组患儿口服孟鲁司特钠,观察组患儿在对照组基础上给予布地奈德气雾剂进行雾化治疗,两组均治疗1周。统计分析两组患儿的临床有效率,肺功能指标,包括第1秒用力呼气容积(FEV1)、用力肺活量(FVC)及FEV1/FVC,对比治疗前后两组患儿血清中EOS、ECP水平的变化。结果:治疗后,观察组的总有效率为97.00%,显著高于对照组的81.00%(P0.05);经治疗后两组患儿肺功能指标均较治疗前明显改善,且观察组患儿优于对照组(P0.05);两组患儿治疗后EOS、ECP水平均低于治疗前,而观察组患儿低于对照组,差异均有统计学意义(P0.05)。结论:孟鲁司特钠联合布地奈德对于小儿哮喘的急性发作具有良好的临床疗效,能显著改善患儿肺功能和血清中炎症因子的水平,减轻患儿体内的炎症反应,值得在临床上推广应用。     

Effect of the ω-acylceramides on the lipid organization of stratum corneum model membranes evaluated by X-ray diffraction and FTIR studies (Part I)

The lipid organization in the outermost layer of the skin, the stratum corneum, is important for the skin barrier function. The stratum corneum lipids are composed of ceramides (CER), free fatty acids (FFA) and cholesterol (CHOL). In the present study Fourier transform infrared (FTIR) and small-angle X-ray scattering (SAXS) techniques were utilized to evaluate the effect of three C18 fatty acid esterified ω-acylceramides (CER EOS) on the lipid organization of stratum corneum model membranes. FTIR spectra (scissoring and rocking bands) showed as a function of temperature significant line-shape changes for both components assigned to the orthorhombic phase. Second-derivative analyzes revealed a significant decrease in the interchain coupling strength (Δν values) for the samples formed by CER EOS with the linoleate (CER EOS-L) and oleate (CER EOS-O) moiety around 28.5 °C. However, only a gradual decrease in the Δν values was noticed for the mixture formed with CER EOS with the stearate moiety (CER EOS-S) over the whole temperature range. In the absence of CER EOS the decrease started already at 25.5 °C, demonstrating that CER EOS stabilized the orthorhombic lattice. This stabilization was most pronounced for the CER EOS-S. Spectral fittings allowed to evaluate the orientation changes of the skeletal plane within the orthorhombic unit cell (θ values) for a given temperature range. From the best-fit parameters (peak area values), a decrease in the orthorhombic phase contribution to the scissoring band was also monitored as a function of the temperature. SAXS studies showed the coexistence of two lamellar phases with a periodicity of ∼5.5 nm (short periodicity phase, SPP) and ∼12 nm (LPP) in the presence of the CER EOS-L and CER EOS-O. However, no diffraction peaks associated to the LPP were detected for CER EOS-S. While CER EOS-S most efficiently stabilized the orthorhombic phase, CER EOS-L and CER EOS-O promoted the presence of the LPP. Therefore, the presence of all three CER EOS as observed in human stratum corneum may contribute to a proper skin barrier function.     

气管哮喘患者血清趋化因子CXCL12水平的表达及其与炎症因子和肺功能的相关性研究

摘要 目的：探讨支气管哮喘患者血清趋化因子CXCL12水平与炎症因子和肺功能的关系。方法：选择2017年10月至2019年10月我院收治的支气管哮喘患者共106例,其中急性发作期67例（急性发作组）、慢性持续期39例（慢性持续组）,另选择50例体检的健康志愿者为对照组,均进行血清CXCL12检测,分析CXCL12与炎症因子、肺功能、嗜酸性粒细胞（EOS）、免疫球蛋白E（IgE）、呼出气一氧化氮（FeNo）的相关性。结果：急性发作期组血清CXCL12、白介素-4（IL-4）、白介素-17A（IL-17A）、白介素-13（IL-13）、EOS、IgE、FeNO水平高于慢性持续期组和对照组（P＜0.05）,慢性持续期组血清CXCL12、IL-4、IL-17A、IL-13、EOS、IgE、FeNO水平高于对照组（P＜0.05）;急性发作期组第1秒用力呼气容积（FEV1）、第1秒用力呼气容积与用力肺活量比值（FEV1/FVC）、第1秒用力呼气容积占预计值百分数(FEV₁ %pred)低于慢性持续期组和对照组（P＜0.05）,慢性持续期组FEV FEV₁、FEV FEV₁/FVC、FEV FEV₁%pred低于对照组（P＜0.05）。多元线性回归分析结果显示血清CXCL12与支气管哮喘患者FEV FEV₁、FEV FEV₁/FVC呈负相关（P＜0.05）,与EOS、IgE、IL-4、IL-17A、IL-13呈正相关（P＜0.05）。结论：CXCL12在支气管哮喘进程中可能发挥促炎作用,血清CXCL12水平可反映患者病情严重程度和肺通气功能。     

Radionuclide transport model for risk evaluation of high-level radioactive waste in Northwestern China

The proper disposal of high-level radioactive waste (HLRW) is highly challenging. Numerical simulations are helpful methods of evaluating the risks of radionuclide transport. This paper examines the hydrogeological conditions of a prospective HLRW repository in China. A regional radionuclide transport model is first constructed using the TOUGH2-MP/EOS7R module at a site in northwestern China to evaluate radionuclide transport behavior. A flow model calibration under a steady state shows that the simulated and observed hydraulic heads match well. Hypothetical radionuclides (⁹⁰Sr, ¹³⁷Cs, ²³⁵U and ²³⁹Pu) are assumed to be instantaneously released at three locations with large groundwater velocities. Transport modeling shows that ²³⁵U is the most sensitive element and has the plume size (2400 m) after 10,000 years. Sensitivity analyses of parameters, including the permeability, distribution coefficient and diffusion coefficient, are carried out. The results show that the distribution coefficient is the most critical parameter for nuclide transport. These findings will provide a preliminary reference for the radionuclide migration process at a prospective HLRW disposal site, which could be informative for safety analyses and further transport in and around the repository system.     

AECOPD合并呼吸机相关性肺炎患者病原菌分布及EOS、RDW联合CPIS对预后的评估价值

摘要 目的：分析慢性阻塞性肺疾病急性加重期（AECOPD）合并呼吸机相关性肺炎（VAP）患者病原菌分布情况,并探讨嗜酸性粒细胞（EOS）、红细胞分布宽度（RDW）联合临床肺部感染评分（CPIS）对预后的评估价值。方法：选取2019年1月～2022年1月我院收治的82例AECOPD合并VAP患者（VAP组）,另选取同期55例未合并VAP的AECOPD患者（非VAP组）;根据VAP组患者治疗后28 d生存情况,将其分为死亡亚组33例和存活亚组49例。检测所有患者外周血EOS、RDW水平并计算CPIS评分,分析AECOPD合并VAP患者病原菌分布情况。采用单因素、多因素Logistic回归分析AECOPD合并VAP患者预后不良的影响因素,采用受试者工作特征（ROC）曲线分析外周血EOS、RDW联合CPIS评分对AECOPD合并VAP患者预后的评估价值。结果： 82例AECOPD合并VAP患者共检测出89株病原菌,革兰氏阴性菌、革兰氏阳性菌、真菌分别占比55.06％、42.70％、2.25％。与非VAP组比较,VAP组外周血EOS、RDW水平及CPIS评分更高（均P＜0.05）。与存活亚组比较,死亡亚组外周血EOS、RDW水平及CPIS评分更高（均P＜0.05）。多因素Logistic回归分析显示,年龄增加和降钙素原、外周血EOS、RDW水平及CPIS评分升高为AECOPD合并VAP患者预后不良的独立危险因素,第1秒用力呼气容积占预计值百分比（FEV₁％）升高为其独立保护因素（均P＜0.05）。ROC曲线分析显示,外周血EOS、RDW联合CPIS评分评估AECOPD合并VAP患者预后的曲线下面积（AUC）大于外周血EOS、RDW及CPIS评分单独评估。结论：AECOPD合并VAP患者病原菌以革兰氏阴性菌为主,外周血EOS、RDW水平及CPIS评分升高与患者预后不良密切相关,三者联合对AECOPD合并VAP患者预后的评估价值较高。     

The importance of the lipoxygenase-hepoxilin pathway in the mammalian epidermal barrier

This review covers the background to discovery of the two key lipoxygenases (LOX) involved in epidermal barrier function, 12R-LOX and eLOX3, and our current views on their functioning. In the outer epidermis, their consecutive actions oxidize linoleic acid esterified in ω-hydroxy-ceramide to a hepoxilin-related derivative. The relevant background to hepoxilin and trioxilin biochemistry is briefly reviewed. We outline the evidence that linoleate in the ceramide is the natural substrate of the two LOX enzymes and our proposal for its importance in construction of the epidermal water barrier. Our hypothesis is that the oxidation promotes hydrolysis of the oxidized linoleate moiety from the ceramide. The resulting free ω-hydroxyl of the ω-hydroxyceramide is covalently bound to proteins on the surface of the corneocytes to form the corneocyte lipid envelope, a key barrier component. Understanding the role of the LOX enzymes and their hepoxilin products should provide rational approaches to ameliorative therapy for a number of the congenital ichthyoses involving compromised barrier function. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.