强脉冲光嫩肤疗效评价及病理变化的研究

目的比较强脉冲光嫩肤治疗前后照片、组织学检查及皮肤纹理数字化图像分析等变化,为研究强脉冲光改善皮肤纹理质地的机制和建立临床疗效评价方法提供可参考依据。方法对58例强脉冲光嫩肤患者治疗前后照片行主观评价;4例行病理检查及胶原纤维免疫组化检查,并对弹力、胶原纤维特殊染色病理片行图像定量分析;2例行透射电镜研究;34例行皮肤纹理数字化图像分析。结果皮肤纹理质地改善有效率62．1％,色素性病变改善有效率84．60％,血管性病变改善有效率81．25％。组织学示真皮Ⅰ、Ⅲ型胶原纤维增多,弹力纤维总量减少,排列均较前整齐;电镜示幼稚成纤维细胞数量增加,成纤维细胞分泌活性增强,胶原纤维排列整齐致密编织成网状。皮肤纹理的数字化图像分析示治疗前后皮肤纹理深度及宽度改善,皮肤平均粗糙度、皮肤算术平均粗糙度及皮肤平均光滑度差异均有统计学意义（均P〈0．01）。结论强脉冲光嫩肤技术对改善皮肤纹理质地的疗效肯定;其机制可能与成纤维细胞活性增强,胶原纤维和弹力纤维的增生与重排有关。     

Characterization of Polyelectrolyte Complexes Based on Maleic Anhydride Alternating Copolymers by Static and Dynamic Light Scattering

The influence of the hydrophobicity of oppositely charged polyelectrolytes based on maleic anhydride alternating copolymers on the complex formation has been investigated by means of DLS and SLS. The change of hydrophobicity of the stock polyions was provided by variation of the comonomer (ethylene, isobutylene and styrene) in the polymer backbone. The particle size and the polydispersity at certain mixing ratios increase with increasing hydrophobicity of the used polyelectrolytes. Below the isoelectric point (1:1 interaction stoichiometry) an increase in the mixing ratio n^?/n⁺ leads to an increasing molar mass and density of the PECs within separate series while the polydispersity is decreasing. The radius of gyration and the hydrodynamic radius are less affected by the mixing ratio in this range. Above the isoelectric point, size and molar mass of the PECs increase strongly and depend on the amount and stabilizing efficiency of the added stabilizing polyelectrolyte. All studied PECs are found to be of spherical shape with different internal structure depending on the used polymers and the mixing ratio.

     

Mesh Size Control of Organic‐Inorganic Hybrid Gels by Means of a Hydrosilylation Co‐Gelation of Siloxane or Silsesquioxane and α, ω‐Non‐Conjugated Dienes

Organic‐inorganic hybrid gels have been synthesized by means of co‐gelation of multi‐functional cyclic siloxane, 1,3,5,7‐tetramethylcyclotetrasiloxane (TMCTS), or cubic silsesquioxane, 1,3,5,7,9,11,13,15‐octakis(dimethylsilyloxy)pentacyclo‐[9,5,1,1,1,1]octasilsesquioxane (POSS), as crosslinking reagents with α,ω‐non‐conjugated dienes, a hexa‐1,5‐diene (HD) and deca‐1,9‐diene (DD) mixture, using hydrosilylation reaction with Pt catalyst. Network structures of the resulting co‐gels have been quantitatively characterized by means of a novel scanning microscopic light scattering system. The feed ratio of HD to DD strongly affects the gelation and mesh size of the co‐gels. The critical concentration of gelation has maximum values in the co‐gelation with a feed ratio of [HD]/[DD] = 1. The mesh‐size of the resulting co‐gels underwent changes with the [HD]/[DD] ratio in the feed, and the structure (geometry) of the crosslinking reagents affect the trend of the mesh size change. The TMCTS‐HD/DD co‐gel obtained with a feed ratio of [HD]/[DD] = 1, showed the minimum mesh size. Whereas the mesh size of the POSS‐HD/DD co‐gel increased with an increase of DD in the feed ratio. The mesh‐size distribution of the co‐gels was narrower than the gels synthesized from single α,ω‐non‐conjugated dienes. Co‐gelation of a TMCT/POSS‐DD system was also investigated, and the critical gelation concentration showed maximum values for the co‐gelation with a feed ratio of [TMCTS]/[POSS] = 1. The mesh size of the co‐gel increased with increasing POSS ratio in the feed.

     

Immunohistochemical and immunochemical study of amyloid in liver affected by systemic Alambda amyloidosis with antibodies against three different regions of immunoglobulin lambda light chain

The purpose of the present paper was to investigate the heterogeneous nature of amyloid deposits in the liver, by immunohistochemical and immunochemical examination of liver samples from cases of immunoglobulin lambda light chain amyloidosis (Alambda amyloidosis) with antibodies generated against the peptides corresponding to the three different regions of the lambda light chain. Amyloid deposits in the hepatic artery tended to react better with anti-lambda(118-134) than with anti-lambda(159-175). Amyloid deposits in the space of Disse tended to react weakly or partially with anti-lambda(118-134) but well with anti-lambda(159-175). Amyloid deposits in the portal vein reacted relatively well with both antibodies. By western blotting of water-extracted amyloid in which amyloid deposits were not stained with anti-lambda(118-134) immunohistochemically, the three antibodies detected 27 kDa bands consistent with the full-length Ig lambda chain and some smaller bands. These findings indicate that amyloid deposits may not be homogeneous in the liver of AL amyloidosis, and that molecular heterogeneity of amyloid fibril protein or a difference in the mode of deposition results in the histopathological heterogeneity of AL amyloid deposits even within a single patient.     

Fabrication of UV epoxy resin masters for the replication of PDMS-based microchips

This paper presents two methods for the fabrication of UV epoxy resin masters for the replication of PDMS-based microfluidic chips. In the first method, the epoxy resin master is fabricated from a negative glass template manufactured using conventional lithography and wet etching techniques. However, in the second method, the master is produced simply by exposing a layer of UV epoxy resin coated on a glass substrate. Although the first method enables the replication of multiple PDMS structures from a single master, the latter method avoids the requirement for a wet chemical etching process and enables the epoxy master to be produced in 40 min or less. The experimental results show that the epoxy resin masters enable the mass production of PDMS replicas with highly precise geometrical tolerances. A series of electrokinetic focusing experiments are performed using PDMS microchips replicated from the current epoxy resin masters. The experimental results obtained for the width of the electrokinetically-focused sample stream under different focusing ratios are found to be in good agreement with the theoretical predictions. The sample handling characteristics of the microfluidic chips are also investigated. It is shown that the sample flow can be electrokinetically pre-focused into a narrow stream and then guided to the desired outlet port by applying a simple voltage control model. Finally, it is demonstrated that through an appropriate alignment of the sample flow and the conductivity gradient, the electrokinetic instability phenomenon can be induced at a relatively low electrical field strength of 0.35 kV/cm.     

Robust circadian rhythm in heart rate and its variability: influence of exogenous melatonin and photoperiod

Heart rate (HR) and heart rate variability (HRV) undergo marked fluctuations over the 24-h day. Although controversial, this 24-h rhythm is thought to be driven by the sleep-wake/rest-activity cycle as well as by endogenous circadian rhythmicity. We quantified the endogenous circadian rhythm of HR and HRV and investigated whether this rhythm can be shifted by repeated melatonin administration while exposed to an altered photoperiod. Eight healthy males (age 24.4 +/- 4.4 years) participated in a double-blind cross-over design study. In both conditions, volunteers were scheduled to 16 h-8 h rest : wake and dark : light cycles for nine consecutive days preceded and followed by 29-h constant routines (CR) for assessment of endogenous circadian rhythmicity. Melatonin (1.5 mg) or placebo was administered at the beginning of the extended sleep opportunities. For all polysomnographically verified wakefulness periods of the CR, we calculated the high- (HF) and low- (LF) frequency bands of the power spectrum of the R-R interval, the standard deviation of the normal-to-normal (NN) intervals (SDNN) and the square root of the mean-squared difference of successive NN intervals (rMSSD). HR and HRV variables revealed robust endogenous circadian rhythms with fitted maxima, respectively, in the afternoon (16:36 hours) and in the early morning (between 05:00 and 06:59 hours). Melatonin treatment phase-advanced HR, HF, SDNN and rMSSD, and these shifts were significantly greater than after placebo treatment. We conclude that endogenous circadian rhythmicity influences autonomic control of HR and that the timing of these endogenous rhythms can be altered by extended sleep/rest episodes and associated changes in photoperiod as well as by melatonin treatment.     

Immunoglobulin free light chains in saliva: a potential marker for disease activity in multiple sclerosis

A new procedure was developed and applied to study immunoglobulin free light chains (FLC) in saliva of healthy subjects and patients with multiple sclerosis (MS). The procedure was based on a Western blot analysis for detection and semiquantitative evaluation of monomeric and dimeric FLCs. The FLC indices accounting for the total FLC levels and for the monomer/dimer ratios of κ and λ FLC were calculated, and the cut‐off values of the FLC indices were determined to distinguish healthy state from MS disease. The obtained FLC index values were statistically different in the saliva of three groups: active MS patients, MS patients in remission and healthy subjects groups. Our FLC monomer–dimer analysis allowed differentiation between healthy state and active MS with specificity of 100% and a sensitivity of 88·5%. The developed technique may serve as a new non‐invasive complementary tool to evaluate the disease state by differentiating active MS from remission with sensitivity of 89% and specificity of 80%.     

天狼猩红饱和苦味酸染色在大鼠胰腺纤维化评价中的应用

目的 应用苦味酸天狼猩红-偏振光法评价长期高脂饮食导致的胰腺纤维化。 方法 建立18周高脂饮食大鼠模型，HE染色观察胰腺形态变化，苦味酸天狼猩红-偏振光法对胰腺纤维化特点进行评价。 结果 长期高脂饮食可以导致大鼠胰腺纤维化改变，对苦味酸天狼猩红染色结果进行图像分析显示胶原纤维含量较正常组明显增加 (p<0.01)，偏光镜下观察示以I、III胶原为主要成分。结论 苦味酸天狼猩红-偏振光法是评价胰腺纤维化胶原沉积的有效方法。     

Phenotypic plasticity of mesenchymal stem cells is crucial for mesangial repair in a model of immunoglobulin light chain-associated mesangial damage

Mesangiopathies produced by glomerulopathic monoclonal immunoglobulin light chains (GLCs) acting on the glomerular mesangium produce two characteristic lesions: AL-amyloidosis (AL-Am) and light chain deposition disease (LCDD). In both cases, the pathology is centered in the mesangium, where initial and progressive damage occurs. In AL-Am the mesangial matrix is destroyed and replaced by amyloid fibrils and in LCDD, the mesangial matrix is increased and remodeled. The collagen IV rich matrix is replaced by tenascin. In both conditions, mesangial cells (MCs) become apoptotic as a direct effect of the GLCs.

MCs were incubated in-vitro with GLCs and animal kidneys were perfused ex-vivo via the renal artery with GLCs, producing expected lesions, and then mesenchymal stem cells (MSCs) were added to both platforms. Each of the two platforms provided unique information that when put together created a comprehensive evaluation of the processes involved. A “cocktail” with growth and differentiating factors was used to study its effect on mesangial repair.

MSCs displayed remarkable phenotypic plasticity during the repair process. The first role of the MSCs after migrating to the affected areas was to dispose of the amyloid fibrils (in AL-Am), the altered mesangial matrix (in LCDD) and apoptotic MCs/debris. To accomplish this task, MSCs transformed into facultative macrophages acquiring an abundance of lysosomes and endocytotic capabilities required to engage in phagocytic functions. Once the mesangial cleaning was completed, MSCs transformed into functional MCs restoring the mesangium to normal. “Cocktail” made the repair process more efficient.     

Timing for the Introduction of Cycled Light for Extremely Preterm Infants: A Randomized Controlled Trial

Day‐night cycled light improves health outcomes in preterm infants, yet the best time to institute cycled light is unclear. The hypothesis of this study was that extremely preterm infants receiving early cycled light would have better health and developmental outcomes than infants receiving late cycled light. Infants born at ≤28 weeks gestation were randomly assigned to early cycled light (ECL) starting at 28 weeks postmenstrual age [PMA] or late cycled light (LCL), starting at 36 weeks PMA. Daylight was 200–600 lux and night was 5–30 lux. Primary outcomes were weight over time and length of hospitalization. Secondary outcomes were hospital costs, sleep development, and neurodevelopment at 9, 18, and 24 months corrected age. Of 121 infants randomized, 118 were included in analysis. Weight gain in the two groups did not differ significantly but increased across time in both groups. In PMA weeks 36–44, the mean weight gain was 193.8 grams in the ECL group compared to 176.3 grams in the LCL group. Effect sizes for weight were Cohen d = 0.26 and 0.36 for 36 and 44 weeks PMA. Infants in the ECL group went home an average of 5.5 days earlier than the LCL group, but this difference was not statistically significant. There were no group differences on neurodevelopmental outcomes. Although statistically non‐significant, clinically important differences of improved weight gain and decreased hospital stay were observed with ECL. The small observed effect sizes on weight during hospitalization should be considered in future cycled light research with extremely preterm infants. © 2017 Wiley Periodicals, Inc.