Wireless micro current stimulation – an innovative electrical stimulation method for the treatment of patients with leg and diabetic foot ulcers

Clinical experience with a new electrical stimulation (ES) technique, the wireless micro current stimulation (WMCS), for the treatment of chronic wounds is described. WMCS transfers the current to any surface wound from a distance, by using oxygen's and nitrogen's ability to exchange electrons. We studied 47 patients with hard‐to‐heal wounds. Patients with venous, arterial and mixed leg ulcers were predominant; other aetiologies such as diabetic foot lesions, pressure ulcers, vasculitis and pyoderma were also included. WMCS treatment protocol specified treatment twice or thrice per week, for 45–60 minutes per session, with 1·5 μA current intensity. Standard wound care was applied to all patients, including compression bandages, if necessary. Clear progress of wound healing, even after 2 weeks, was observed in all cases. The mean reduction of the wound surface after WMCS treatment was 95% in 8 weeks. Complete healing was achieved within 3 months for the majority of the cases. No clinical side effects were observed. WMCS technology significantly accelerated wound healing for patients with hard‐to‐heal wounds of different aetiologies. This new therapy offers multiple advantages compared with the previous methods of ES, as it is contactless, free of pain and very easy to use.     

控制性低中心静脉压对脊柱手术患者血管外肺水和失血量的影响

目的观察术中行控制性低中心静脉压(controlled low central venous pressure,CLCVP)对脊柱手术患者血管外肺水(extravascular lung water,EVLW)和失血量的影响。方法 36例择期行腰椎后路椎管减压植骨融合术的患者随机分为CLCVP组(L组)和对照组(C组),每组18例。L组于手术开始后通过限制输液联合静脉输注硝酸甘油使CVP维持在2~4cm H2O,植骨融合完成后迅速扩容使CVP恢复正常。C组常规补液,维持CVP在6~12cm H2O。分别于麻醉诱导后仰卧位(T0)、降压前俯卧位(T1)、CLCVP后30min(T2)、60min(T3)、90min(T4)和手术结束时(T5)记录血流动力学和EVLWI的变化;记录术毕总失血量和总输血量,单独记录CLCVP期间失血量与CVP和MAP相关性。结果与T0时比较,T1时两组CVP、T2时L组SVRI明显升高(P0.05)。与T1时比较,T4时两组HR明显增快、CI明显升高(P0.05),T2~T4时L组MAP、CVP、ITBVI和T4时C组MAP、CVP明显降低(P0.05)。与C组比较,L组T2~T4时MAP、CVP,T3、T4时SI明显降低(P0.05),而SVRI明显升高(P0.05),术中L组总失血量、总输血量和总输液量、尿量均明显减少(P0.05)。结论脊柱外科手术中应用CLCVP在减少术中失血量和输血量的同时,对患者的血流动力学和EVLW无不良影响。     

Viscosity of deeply supercooled water and its coupling to molecular diffusion

The viscosity of a liquid measures its resistance to flow, with consequences for hydraulic machinery, locomotion of microorganisms, and flow of blood in vessels and sap in trees. Viscosity increases dramatically upon cooling, until dynamical arrest when a glassy state is reached. Water is a notoriously poor glassformer, and the supercooled liquid crystallizes easily, making the measurement of its viscosity a challenging task. Here we report viscosity of water supercooled close to the limit of homogeneous crystallization. Our values contradict earlier data. A single power law reproduces the 50-fold variation of viscosity up to the boiling point. Our results allow us to test the Stokes–Einstein and Stokes–Einstein–Debye relations that link viscosity, a macroscopic property, to the molecular translational and rotational diffusion, respectively. In molecular glassformers or liquid metals, the violation of the Stokes–Einstein relation signals the onset of spatially heterogeneous dynamics and collective motions. Although the viscosity of water strongly decouples from translational motion, a scaling with rotational motion remains, similar to canonical glassformers.Water, considered as a potential glassformer, has been a long-lasting topic of intense activity. Its possible liquid–glass transition was reported 50 years ago to be in the vicinity of 140?K (1, 2). However, ice nucleation hinders the access to this transition from the liquid side. Bypassing crystallization requires hyperquenching the liquid at tremendous cooling rates, ca. 10⁷?K ? s^?1 (3). As a consequence, many questions about supercooled and glassy water and its glass–liquid transition remain open (4–7).As an example, crystallization of water is accompanied by one of the largest known relative changes in sound velocity, which has been attributed to the relaxation effects of the hydrogen bond network (8, 9). Indeed, whereas the sound velocity is around 1,400 m⋅s−1 in liquid water at 273?K, it reaches around 3,300 m⋅s−1 in ice at 273?K and a similar value in the known amorphous phases of ice at 80?K (10). Such a large jump is usually the signature of a strong glass, i.e., one in which relaxation times or viscosity follow an Arrhenius law upon cooling. However, pioneering measurements on bulk supercooled water by NMR (11) and quasi-elastic neutron scattering (12), as well as recent ones by optical Kerr effect (8, 9), reveal a large super-Arrhenius behavior between 340 and 240?K, similar to what is observed in fragile glassformers (13, 14). The temperature dependence of the relaxation time is well described by a power law (8, 9), as expected from mode-coupling theory (15, 16), which usually applies well to liquids with a small change of sound velocity upon vitrification. Based on these and other observations, it has been hypothesized that supercooled water experiences a fragile-to-strong transition (17). This idea has motivated experimental efforts to measure dynamic properties of supercooled water and has received some indirect support from experiments on nanoconfined water (18–20) and from simulations (21, 22).In usual glassformers, many studies have focused on the coupling or decoupling between the following dynamic quantities: viscosity (η) and self or tracer diffusion coefficients for translation (D_t) and rotation (D_r). If objects as small as molecules were to follow macroscopic hydrodynamics, one would expect that the preceding quantities would be related through the Stokes–Einstein (SE), D_t ∝ T/η, and Stokes–Einstein–Debye (SED), D_r ∝ T/η, relations, where T is the temperature. These relations are indeed obeyed by many liquids at sufficiently high temperature. However, they might break down at low temperature. Pioneering experiments were performed by the groups of Sillescu (23–25) and Ediger (26–28) where a series of molecular glassformers were investigated. SE relation is obeyed at sufficiently high temperature but violated around 1.3T_g, where T_g is the glass transition temperature, thus indicating decoupling between translational diffusion and viscosity. In contrast, it was observed for ortho-terphenyl (23, 24, 26) that rotational diffusion and viscosity remain strongly coupled (i.e., obey the SED relation) even very close to T_g. A corollary is that translational and rotational diffusion decouple from each other at low temperature. These observations imply that deeply supercooled liquids exhibit spatially heterogeneous dynamics (29–31). Dynamic heterogeneities have been confirmed by direct observations of several single fluorescent molecules immersed in ortho-terphenyl (32) or nanorods immersed in glycerol (33). Physically different systems also show analogous behavior. Colloids near the colloidal glass transition violate SE but obey SED (34). In the metallic alloy Zr₆₄Ni₃₆, SE relation is even violated without supercooling, more than 35% above the liquidus temperature (35). This has also been related to the emergence of dynamic heterogeneities (36).For water, SE already breaks down at ambient temperature, which corresponds to around 2.1?T_g (T_g ? 136?K). Molecular dynamics simulations (37–39) have proposed that this occurs concurrently to dynamic heterogeneities caused by a putative liquid–liquid critical point. However, SE and SED also fail by application of high pressure at 400?K (40) where no liquid–liquid transition is expected. To gain more insight, the test of SE and SED in supercooled water deserves further investigation. Translational self-diffusion coefficient D_t (41) and rotational correlation time τ_r (assumed to scale as 1/D_r) (42) have thus been measured down to the homogeneous crystallization temperature (238?K) at ambient pressure. Their comparison reveals a decoupling between rotation and translation that increases with supercooling (42), similar to glassformers. However, viscosity data are needed for a direct test of SE and SED relations. Quite surprisingly, there are only two sets of data for the viscosity η at significant supercooling. Using Poiseuille flow in capillaries, Hallett (43) reached 249.35?K, and Osipov et al. (44) reached 238.15?K. However, the two sets disagree below 251?K, with an 8% difference at 249?K, beyond the reported uncertainties. The measurements in ref. 44 are suspected of errors (45) because of the small capillary diameter used. Here we report η at ambient pressure down to 239.27?K. Our study completes the knowledge of the main dynamic parameters of water down to the homogeneous crystallization limit and allows us to check the coupling of viscosity to molecular translation or rotation, as has been done for usual glassformers.     

Short-Term Functional Adaptation of Aquaporin-1 Surface Expression in the Proximal Tubule,a Component of Glomerulotubular Balance

Transepithelial water flow across the renal proximal tubule is mediated predominantly by aquaporin-1 (AQP1). Along this nephron segment, luminal delivery and transepithelial reabsorption are directly coupled, a phenomenon called glomerulotubular balance. We hypothesized that the surface expression of AQP1 is regulated by fluid shear stress, contributing to this effect. Consistent with this finding, we found that the abundance of AQP1 in brush border apical and basolateral membranes was augmented >2-fold by increasing luminal perfusion rates in isolated, microperfused proximal tubules for 15 minutes. Mouse kidneys with diminished endocytosis caused by a conditional deletion of megalin or the chloride channel ClC-5 had constitutively enhanced AQP1 abundance in the proximal tubule brush border membrane. In AQP1-transfected, cultured proximal tubule cells, fluid shear stress or the addition of cyclic nucleotides enhanced AQP1 surface expression and concomitantly diminished its ubiquitination. These effects were also associated with an elevated osmotic water permeability. In sum, we have shown that luminal surface expression of AQP1 in the proximal tubule brush border membrane is regulated in response to flow. Cellular trafficking, endocytosis, an intact endosomal compartment, and controlled protein stability are the likely prerequisites for AQP1 activation by enhanced tubular fluid shear stress, serving to maintain glomerulotubular balance.     

红花标准汤剂的质量评价

目的:建立红花标准汤剂的质量控制方法。方法:收集有代表性的14批红花,制备红花标准汤剂,计算出膏率、指标成分转移率和溶液pH等参数,评价工艺的稳定性;建立指标成分含量测定和指纹图谱方法,采用UPLC-Q-TOF/MS对主要色谱峰进行结构确认,明确红花标准汤剂中的主要化学成分。结果:标准汤剂出膏率32.6%,羟基红花黄色素A的转移率61.2%,pH 4.1;标准汤剂中羟基红花黄色素A平均质量浓度3.6 g·L~(-1),指纹图谱相似度均0.9,标准汤剂的主要成分为黄酮类。结论:建立了系统评价红花标准汤剂的质量评价方法,为所有源于红花水煎液的制剂的质量标准制定提供参考,所得红花标准汤剂的指标成分转移率高、质量均一性良好。     

栀子标准汤剂的质量评价方法考察

目的:建立栀子标准汤剂的质量评价方法,为所有源于栀子水提液的制剂的质量标准制定提供参考。方法:制备15批栀子标准汤剂,测定其出膏率、指标成分转移率和pH;建立栀子标准汤剂的UPLC指纹图谱并对主要色谱峰进行质谱鉴定,离子化模式为正、负离子,离子源温度150℃,脱溶剂气体为高纯度氮气,温度550℃,流速800 L·h~(-1),毛细管电压1.0 kV,锥孔电压30 V,扫描范围m/z 50~1 200。结果:栀子标准汤剂的平均出膏率28.4%,栀子苷转移率77.7%,p H均为4。所有样品的指纹图谱相似度均0.99,栀子标准汤剂的主要成分为栀子苷。结论:建立的栀子标准汤剂的质量评价方法稳定可行、重复性好,该评价方法灵敏、准确,为所有源于栀子水煎剂的制剂的质量控制提供参考。     

Risk Factors for Dental Fluorosis in Pediatric Dental Patients

Objectives: Concerns have been raised recently about whether a substantial amount of dental fluorosis is resulting from the increased use of fluoride from various sources. The purposes of this study were to determine the prevalence and severity of dental fluorosis in a sample of pediatric patients seeking dental treatment in a university pediatric dental clinic and to evaluate sources of fluoride as risk factors for dental fluorosis. Methods : A convenience sample of 157 children aged 8 to 17 years were examined for dental fluorosis using the Tooth Surface Index of Fluorosis (TSIF). Fluoride history questionnaires assessing previous exposure to fluoride during the first eight years of life were completed by the children's parents. Fluoride exposures were compared among 54 cases and 54 matched controls using a case-control retrospective design. Results : Fluorosis was found in 72 percent of the children, but was generally quite mild. The risk of fluorosis was significantly greater for children who had greater exposure to fluoridated water and who used larger amounts of fluoridated toothpaste up to age eight. Conclusions : This study provided evidence that increased use of fluoride toothpaste may be a risk factor for dental fluorosis. The results suggest prudent use of dentifrice by young children to minimize the risk of fluorosis.     

Use of Hoy's solubility parameters to predict water sorption/solubility of experimental primers and adhesives

Self-etching primers and adhesives contain very hydrophilic acidic monomers that result in high water sorption/solubilities of their polymers. However, the chemical composition of these products varies widely. The purpose of this work was to vary the chemical composition of experimental self-etching primers and adhesives to determine if the water sorption/solubility of the polymers were affected in a predictable manner. The Hoy's solubility parameters of these mixtures were calculated to permit ranking of the degree of hydrophilicity of the polymers. Water sorption/solubility was measured according to ISO 4049. The results showed highly significant (R(2) = 0.86, P < 0.001) correlations between water sorption and Hoy's solubility parameter for polar forces (delta(p)) of the polymers. Similar correlations were obtained between polymer solubility and delta(p). When these results were compared with previously published results obtained with more hydrophobic resins, excellent correlations were obtained, indicating that Hoy's delta(p) values may be used to predict the water sorption behavior of methylmethacrylate polymers.     

北京市怀柔区儿童口腔健康状况的调查与分析--怀柔区调节水氟浓度预防龋齿可行性研究

目的 :通过对北京市怀柔区儿童的口腔健康流行病学调查 ,为该区开展调节水氟浓度预防龋齿提供可行性依据。方法 :采用随机、整群抽样方法调查 3～ 15岁 6个年龄组儿童共 15 62人 ,调查内容包括龋病患病状况、12岁和 15岁组氟牙症患病状况。结果 :怀柔区儿童 5岁乳牙患龋率 87.2 % ,龋均 5 .93 ,12岁恒牙患龋率67.7% ,龋均 1.73 ,均高于全国和北京市平均患龋水平。 12岁儿童氟牙症指数为 0 .0 2 ,15岁组氟牙症指数为 0。讨论 :怀柔区自来水覆盖区属于龋病较严重地区 ,氟牙症非流行区。已知所调查地区水氟浓度 <0 .2 ppm ,因此 ,从流行病学研究方面可以认为该地区适合于调节水氟浓度预防龋齿。     

Consumption of nonpublic water: implications for children's caries experience

There are concerns that the consumption of unfluoridated bottled and tank water may put children at increased risk of developing caries. OBJECTIVES: The aim of this study was to investigate the relationship between nonpublic water consumption (either from bottles or rainwater tanks) and socioeconomic status (SES) and both deciduous and permanent caries experience. METHODS: A random sample of children enrolled in the School Dental Service of South Australia participated in the study (response rate = 71.8%, n = 9988). RESULTS: Forty-five per cent of children had greater than 50% lifetime consumption of nonpublic water while 36% of children had 0% lifetime consumption. Increased use of nonpublic water occurred for children from lower socioeconomic groups, two-parent families and children from nonmetropolitan areas, with these results most likely a result of the residential location of the children. Multivariate modelling revealed a significant positive relationship between deciduous caries experience and consumption of nonpublic water, even after controlling for the age and sex of the child, SES and residential location. This relationship was significant only for those children with 100% lifetime availability of fluoridated water. The effect of consumption of nonpublic water on permanent caries experience was not significant. It is postulated that these findings may result from the lower caries activity in the permanent dentition of children aged 10-15 and possible dietary confounders. CONCLUSION: Recommendations are made for the addition of fluoride to bottled water, especially with regard to the oral health of younger children.