Dielectric behavior of pulmonary edema induced in the rat lung

The dielectric properties (conductivity, kappa and relative permittivity, epsilon) of excised rat lung are modified by lung air and water content. The measurements of these quantities were made over the frequency range of 10 kHz to 100 MHz with an open-ended coaxial probe. The following relationships were analyzed in an oleic acid-induced pulmonary edema model using 18 animals: the spectra of kappa, epsilon and the loss tangent as a function of lung air and water content. Secondly, an isolated-perfused lung system was produced to induce a gradual increase in lung water. The time course of kappa, epsilon and the loss tangent for one excised lung was analyzed. The principal findings were: (i) a decrease in kappa and epsilon with increasing air content, (ii) an increase in kappa and epsilon with increasing water content, and (iii) a good correlation between lung water content and maximum loss tangent that was insensitive to changes in air content. We conclude that this technique could provide a quantitative assessment of lung water during pulmonary edema formation.     

Nitric oxide used to test pulmonary gas exchange in rabbits

 To evaluate whether nitric oxide (NO) is an appropriate test gas for assessing pulmonary gas exchange, we determined the rates of disappearance from the alveolar space (λ) of NO and singly and doubly ¹⁸O-labelled carbon dioxide (C¹⁶O¹⁸O, C¹⁸O₂) by performing single-breath manoeuvres on seven artificially ventilated rabbits. By exploiting unique features of both isotopic species and by analysing pulmonary gas transport and λ values with a commonly used model, we found that diffusion forms 98±6% (mean ± SD) of the overall resistance to alveolar-capillary NO transfer. This means that measurements of pulmonary NO uptake reveal the entire diffusive properties of the alveolar-capillary membrane, because the extremely fast binding of NO to haemoglobin negates the ”reactive” component within red blood cells of pulmonary capillaries. Received: 8 May 1998 / Received after revision: 12 August 1998 / Accepted: 17 August 1998     

Fear of Movement/Injury in the General Population: Factor Structure and Psychometric Properties of an Adapted Version of the Tampa Scale for Kinesiophobia

In recent years, several studies have pointed out the importance of pain-related fear in the development and maintenance of chronic pain. An important instrument for measuring pain-related fear in the context of low back pain is the Tampa Scale for Kinesiophobia (TSK). Recently, a version of this questionnaire has been developed for administration among the general population (TSK-G). To determine the factor structure of the TSK-G, data from a random sample of the Dutch general population were studied separately for people who had had back complaints in the previous year, and people who had been without back complaints. For both groups the TSK-G appeared to consist of one, internally consistent, factor of 12 items. The one-factor TSK-G also appeared valid after comparison with scores on measures of catastrophizing and general health status.     

Novel Semi‐Fluorinated Poly(ether imide)s Derived From 4‐(p‐Aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl

An unsymmetrical diamine monomer 4‐(p‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl has been synthesized successfully. This monomer leads to the synthesis of different novel poly(ether imide)s when reacted with different dianhydrides like pyromellatic dianhydride (PMDA), benzophenone tetracarboxylic acid dianhydride (BTDA), 2,2‐bis(3,4‐dicarboxyphenyl) hexafluoropropane (6FDA), and oxy diphthalic anhydride (ODA). The poly(ether imide) prepared from this monomer on reaction with 6FDA is soluble in several organic solvents such as N‐methylpyrolidinone (NMP), dimethylformamide (DMF), N,N‐dimethylacetamide (DMAc), tetrahydrofuran (THF), and CHCl₃. The poly(ether imide)s prepared from BTDA and ODA are soluble in NMP, DMF, and DMAc but not in THF or CHCl₃, whereas the polymer prepared from PMDA is soluble only in NMP. The water uptake value for these poly(ether imide) films is very low (0.2–0.5%), and exhibited low dielectric constants (2.81 at 1 MHz). The polymers exhibited high thermal stability up to 532 °C in air for 5% weight loss, and high glass transition temperatures up to 288 °C. The polymer exhibited high tensile strength up to 135 MPa, modulus 3.2 GPa, and elongation at break up to 25%, depending on the exact polymer structure.

The structure of the poly(ether imide) synthesised from 4‐(p‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl and 2,2‐bis(3,4‐dicarboxyphenyl) hexafluoropropane. This polymer was soluble in many organic solvents.     

Pretherapeutic flow cytometric DNA investigations in radiotherapy patients with maxillo-facial carcinomas

In order to analyze the possible meaning of cellular DNA content and cell cycle phases for the radiosensitivity and the prognosis of human malignant tumors, flow cytometric measurements have been performed in biopsies of 131 patients with histologically proven squamous cell carcinomas of the maxillo-facial region. In two-thirds of the patients (88/131; 67%), aneuploid tumor cell lines have been found, only 33% (43/131) had a diploid DNA distribution pattern. The average DNA index (DI) of the aneuploid carcinomas was 3.4 +/- 0.6 (normal nonmalignant tissue DI = 2.0). The frequency of S-phase cells, which represents the "proliferative activity", was between 4.8 and 63.2%, regardless of the ploidy stages. The aneuploid carcinomas had about twice as many S-phase cells (mean 23.7 +/- 11.8%) than diploid tumors (mean 12.7 +/- 4.8%). Mean survival for patients with diploid carcinoma and aneuploid carcinoma was 12 and 9.5 months, respectively. Concerning the relationship of S-phase frequency and survival times in our material there was a high negative statistical correlation (Spearman-Rank test) in patients with diploid carcinomas. A high S-phase fraction resulted in short survival times. No correlation was found in the aneuploid carcinomas: patients with tumors in high S-phase values in their biopsies showed no difference in prognosis in comparison to tumors with lower S-phase fractions.     

Optimum support properties for protein separations by high-performance size exclusion chromatography

Optimum chromatographic properties of high performance size exclusion chromatography (HPSEC) of proteins, such as resolution, molecular weight accuracy and recovery, are obtained on packings and columns with tailor-made physical and chemical structures, employed at properly adjusted eluent compositions and operation conditions. SEC-theory suggests that a broad molecular weight fractionation range and high linearity of the log-linear calibration plot can be achieved by the use of two packings (10- and 80-nm pore size, characterized by a pore-size distribution (psd) equal to or less than 1 decade and by equal internal column porosity (p)), rather than a single 30- to 50-nm pore-size packing with a wide psd. Favourably high-phase ratios of (p)/(o)/ 1.0 for HPSEC columns were accomplished with a minimum interstitial column porosity (o) and a high value for the internal column porosity (p) (the specific pore volume, nu(p), multiplied by the packing density, varrho(p).) Ligands such as diol, N-acetoxyamino and oligomeric ether with a propyl- or propoxy-spacer bonded to the silica at the highest density appear to provide high mass recovery and bioactivity as well as chemical stability. Such packings, available in 3-5 mum particle size ranges of narrow distribution, packed into columns 6 mm i.d. and 500 mm in length, offer the best compromise with respect to resolution, speed and pressure drop. More careful studies are required to explain the effects of protein conformational changes and interconversions during elution on HPSEC columns.     

一种复合微生物菌肥对穿心莲生长、品质及土壤性质的影响

目的：研究一种微生物复合菌肥对穿心莲生长、品质及土壤性质的影响,旨在为穿心莲栽培生产中微生物复合菌肥的应用提供依据。方法：通过盆栽的共5个处理试验,CK（不施肥）组、A处理（施化肥）组、B处理（施微生物菌肥,施用量为2.5 g·kg-1土）组、C处理（施微生物菌肥,施用量为7.5 g·kg-1土）组、D处理（施微生物菌肥,施用量为12.5 g·kg-1土）组,研究一种复合微生物菌肥对穿心莲的农艺性状、有效成分含量及根际土壤细菌、放线菌、真菌的数量和土壤理化性质的影响。结果：施加一定量的复合微生物菌肥,穿心莲的株高、叶片数、叶面积、地上部、地下部鲜重较CK组和A处理组显著升高,不同生长期有差异。复合微生物菌肥对穿心莲内酯、脱水穿心莲内酯、新穿心莲内酯及14-去氧穿心莲内酯含量影响有差异,与CK组、A处理组比较,C处理组的穿心莲内酯分别明显升高26.13%、13.23%(P<0.05);新穿心莲内酯的含量随微生物菌肥施加量的增加而增加,在D处理组下的效应最显著,与CK组、A处理组比较,分别明显升高9.06%、50.33%(P<0.05);B处理组的14-去氧穿心莲内酯较A处理组...     

Rasch Analysis of the Pediatric Quality of Life Inventory 4.0 Generic Core Scales Administered to Patients With Duchenne Muscular Dystrophy

ObjectivesThe objective of this study was to examine the psychometric properties of the Pediatric Quality of Life Inventory 4.0 Generic Core Scales (PedsQL 4.0 GCS) in Duchenne muscular dystrophy (DMD), a rare, severely debilitating, and ultimately fatal neuromuscular disease.MethodsPatients with DMD were recruited from 20 centers across 9 countries as part of the Cooperative International Neuromuscular Research Group Duchenne Natural History Study (NCT00468832). The psychometric properties of the PedsQL 4.0 GCS were examined using Rasch analysis.ResultsIn total, 329 patients with DMD (mean age 9 years, range 3–18 years, 75% ambulatory) completed the PedsQL 4.0 GCS. The most difficult instrument items, expressing the greatest loss in health-related quality of life, were those associated with emotional well-being (eg, being teased by other children, feeling sad, and not making friends), as opposed to somatic disability (eg, lifting heavy objects, participating in sports, and running). The mean item and person fit residuals were estimated at 0.301 (SD: 1.385) and −0.255 (1.504), respectively. In total, 87% (20 of 23) of items displayed disordered thresholds, and many exhibited nontrivial dependency. The overall item-trait interaction χ² value was 178 (115 degrees of freedom, P<.001). Our analysis also revealed significant issues with differential item functioning, and by investigating residual principal component loadings, the PedsQL 4.0 GCS total score was found to be multidimensional.ConclusionsThe PedsQL 4.0 GCS records information clinically relevant to patients with DMD, but the total scale score may not be fit for purpose as a measure health-related quality of life in this disease population.     

聚吡咯／聚合物固体电解质双层复合膜研究

在聚合物固体电解质（聚乙二醇不饱和聚酯网络－LiClO4)中进行吡咯聚合原位制得了聚吡咯／聚合物固体电解质双层复合膜。用扫描电镜观察复合膜的界面结构,用循环伏安和交流阻抗法研究了复合膜的电化学杂脱掺杂性能。结果表明,聚吡咯／聚合物固体电解质双层复合膜具有相互穿插渗透的固／固密接界面结构,这种界面结构改善了聚吡咯和聚俣物固体电解质间的界面接触,提高了聚吡咯在聚俣物固体电解质中的电化学掺杂脱掺杂性能。     

3味山姜属中药黄酮类成分对大鼠环核苷酸水平及交感神经-肾上腺轴的影响

目的：观察高良姜、大高良姜、红豆蔻黄酮类成分对胃溃疡寒证大鼠环核苷酸水平及交感神经-肾上腺轴的影响,探讨3味山姜属中药温热药性的物质基础。方法：采用灌服冰知母水煎液与15%冰乙酸制备大鼠胃溃疡寒证模型,以干姜姜辣素为阳性对照,采用酶联免疫吸附试验（ELISA）法测定腺苷酸环化酶（AC）、磷酸二酯酶2（PDE2）、环磷酸腺苷（cAMP）、环磷酸鸟苷（cGMP）、促肾上腺皮质激素（ACTH）、多巴胺β羟化酶（D-β-H）含量。结果：与空白组比较,胃溃疡寒证模型组大鼠胃组织AC、cAMP含量及cAMP/cGMP比值显著降低,PDE2含量显著升高（P<0.01）。与模型组比较,高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织AC含量升高;高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织PDE2含量显著降低,cAMP含量、cAMP/cGMP比值显著升高（P<0.01或P<0.05）。结论：3味山姜属中药黄酮类成分通过调节胃溃疡寒证大鼠环核苷酸水平从而促进交感神经-肾上腺轴功能活动的作用,也体现出黄酮类成分药性温热。