Insulin resistance causes impaired vasodilation and hypofibrinolysis in young women with polycystic ovary syndrome

INTRODUCTION: Insulin resistance, a novel cardiovascular risk factor, is often associated with increased plasminogen activator inhibitor-1 levels and impaired vasodilation. Insulin infusion in the forearm induces plasminogen activator inhibitor-1 and tissue plasminogen activator expression and endothelium-dependent vasodilation in normal subjects. The present study explores the relationship between insulin-induced vasodilatory and fibrinolytic properties of the endothelium in women with polycystic ovary syndrome, frequently affected by insulin resistance and early atherosclerosis. MATERIALS AND METHODS: Metabolic, hormonal and fibrinolytic parameters were evaluated in 64 patients with polycystic ovary syndrome (19 insulin-resistant and 45 insulin-sensitive) and in 25 controls. In 16 women with polycystic ovary syndrome, 8 insulin-resistant and 8 insulin-sensitive, blood flow, plasminogen activator inhibitor-1 and tissue plasminogen activator expression were evaluated during insulin infusion into the forearm. RESULTS: Elevated basal plasminogen activator inhibitor-1 levels were found in women with polycystic ovary syndrome, correlating directly with insulin levels. Plasminogen activator inhibitor-1 expression increased during insulin infusion in all women with polycystic ovary syndrome, but was delayed and sustained in insulin-resistant patients (p<0.01). Vasodilatory response to insulin was blunted (p<0.01) and tissue plasminogen activator expression abolished in insulin-resistant patients (p<0.01). CONCLUSION: Our study demonstrates that women with polycystic ovary syndrome and insulin resistance show a blunted endothelial-dependent vasodilation. The impaired endothelial release of tissue-plasminogen activator and the sustained plasminogen activator inhibitor-1 release during insulin infusion suggest a hypofibrinolytic state in PCOS patients with insulin resistance. This hemodynamic and fibrinolytic derangement may contribute to the pathogenesis of early atherosclerosis in insulin resistance.     

Structural Effect on Thermal Cure and Property of Naphthalene‐Based Epoxies: Preparation and Characterization

Summary: Three naphthalene‐based epoxy monomers containing different size of linkages between two naphthalene rings: C? C covalent bond ( 1 ), methylene ( 2 ), cycloaliphatic hydrocarbon derived from limonene ( 3 ) were prepared, and the effect of molecular structure on thermal cure behavior and property analyzed. Judged from the combination of the dynamic DSC and isothermal FTIR results, the cure reactivities were found to increase in the order of 1 > 2 > 3 when dicyandiamide was used in the curing systems, and the situation was slightly different in the monomer/4,4′‐methylenedianiline systems. The differences in reactivity as well as in thermal and mechanical properties for the epoxies can be attributed to the differences of configuration and conformational changes during the formation of crosslinked networks. These thermosets exhibited high glass transition temperature (T_g) and had excellent thermal oxidative resistance.

DSC thermograms for epoxy/dicyandiamide systems at a heating rate of 10 °C · min^?1.     

Mechanisms of Moisture Sorption in Barrier Polymers Used in Food Packaging: Amorphous Polyamide vs. High‐Barrier Ethylene‐Vinyl Alcohol Copolymer Studied by Vibrational Spectroscopy

The nature of the association between sorbed water and two high‐barrier hydrophilic polymers used in oxygen‐sensitive food packaging, and exhibiting opposite oxygen barrier behavior in the presence of moisture, has been studied by FT‐Raman and FT‐Infrared spectroscopy. The polymers considered in this work were an ethylene‐vinyl alcohol copolymer with superior oxygen barrier properties (32 mol‐% of ethylene EVOH) and an amorphous polyamide (aPA). The results revealed that for the latter glassy amorphous polymer, water molecules associate with the C?O and N? H groups of the ca. 10% “free” amide moieties, being the excess sorbed water self‐associated in clusters; thus, moisture sorption does not appear to disrupt the originally present hydrogen‐bonded amide groups. This “unusual” behavior leads to an overall increase in the extension of the hydrogen‐bonding, which may help explain the lower oxygen permeability displayed by the aPA with increasing relative humidity on the basis of the known free‐volume competing mechanism. Differently, water sorption appears to progressively disrupt the strong polymer self‐association present in the very efficient high‐barrier semicrystalline EVOH material by hydrogen‐bonding to hydroxyl groups, hence leading to the well‐known highly plasticized rubbery structure with much lower intermolecular cohesion and oxygen barrier.

FT‐IR spectra of severely dried, dry (dotted), and water‐equilibrated (thicker line) aPA in the range 2 600–3 800 cm^?1.     

药用矿物蒙脱石的红外光谱分析

目的：弄清蒙脱石层状晶体结构中水的变化规律,为其药用机制研究和药物的开发利用提供依据。方法：从粘土矿物中分离纯化蒙脱石,运用红外光谱分析技术,对蒙脱石的化学结构进行分析。结果：得到了有关蒙脱石分子水的信息和化学结构变化的基本规律。结论：蒙脱石是一种膨胀吸附性粘土矿物,可作为药物活性成分或赋形剂。     

Afferent synaptic contacts on glycine-immunoreactive neurons in the rat cuneate nucleus

This study was aimed to clarify whether the primary afferent terminals (PATs), GABAergic terminals, and glutamatergic terminals made direct synaptic contacts with glycine-IR neurons in the cuneate nucleus of rats. In this connection, injection of the anterograde tracer WGA-HRP into brachial plexus, antiglycine preembedding immunoperoxidase, and anti-GABA, along with antiglutamate postembedding immunogold labeling, were used to identify the PATs, glycine-IR neurons, GABA-IR terminals, and glutamate-IR terminals, respectively. The present results showed that HRP-labeled PATs, immunoperoxidase-labeled glycine-IR terminals, immunogold-labeled GABA-IR, and glutamate-IR terminals made axodendritic synaptic contacts with immunoperoxidase-labeled glycine-IR neurons. The latter three presynaptic elements also formed axosomatic synapses with glycine-IR neurons. Statistical analysis has shown that the minimum diameter of the glycine-IR dendrites postsynaptic to the above-mentioned four presynaptic elements did not differ significantly. In addition, the synaptic ratio of the glutamate-IR terminals on the glycine-IR dendrites was higher than that of GABA-IR terminals. The synaptic ratio of the GABA-IR terminals on glycine-IR dendrite was in turn higher than that of the PATs and glycine-IR terminals. It is suggested that the PATs and glutamate-IR terminals on the glycine-IR neurons may be involved in subsequent postsynaptic inhibition for spatial precision of lateral inhibition. On the other hand, the GABA-IR and glycine-IR terminals which make synaptic contacts with the dendrites of glycine-IR neurons may provide a putative means for disinhibition or facilitation to maintain the baseline neuronal activity in the rat cuneate nucleus. The results of quantitative analysis suggest that glutamate act as the primary excitatory neurotransmitter, while GABA, when compared with glycine, may serve as a more powerful inhibitory neurotransmitter on glycine-IR neurons in the rat cuneate nucleus.     

氟比洛芬磷脂固体分散体的制备和特性

以氟比洛芬（1）磷脂固体分散体在水中45min时的溶出度为指标，用正交试验优化制备工艺；对固体分散体进行差示扫描量热分析和红外扫描，并考察了溶解度与不同pH条件的溶出度。结果表明，所得1固体分散体能显著改善1的溶解度，其在pH4．0、7．2的缓冲溶液及蒸馏水中45min时的溶出度均在70％以上。     

药用菊花不同提取部位的红外光谱分析

目的:考察不同提取部位药用菊花的红外光谱,全面描述药用菊花红外图谱特征。方法:不同极性溶剂提取得到药用菊花不同提取部位,利用现代红外光谱技术,在对谱图进行小波消噪的基础上,分析不同提取部位的红外谱图,提取红外谱图特征。结果:不同提取部位(挥发油部位、乙酸乙酯部位、水部位)药用菊花红外谱图的特征明显。结论:红外光谱技术结合溶剂提取分析药材宏观特征,是对中药材无损分析的有利补充,可进一步完善中药材红外数据库,能够科学的描述中药材。     

银柴胡类生药的光谱鉴定研究

目的：对来源于石竹科４属（繁缕属、蚤缀属、蝇子草属、丝石竹属）９种植物披针叶繁缕、叉歧繁缕、灯心草蚤缀、腺毛蚤缀、蝇子草、旱麦瓶草、大叶丝石竹、长蕊丝石竹、尖叶丝石竹根的银柴胡类生药进行鉴定研究。方法：测定９种生药乙醇提取物的紫外及红外光谱。结果：各属植物根的紫外及红外光谱有一定差异。结论：利用紫外光谱及一阶导数光谱均可鉴别《中国药典》品种和非《中国药典》品种,并可区分不同的属,红外光谱法能够将繁缕属与其它属区别开来。     

Dark-Blood Delayed Enhancement Cardiac Magnetic Resonance of Myocardial Infarction

Objectives

This study introduced and validated a novel flow-independent delayed enhancement technique that shows hyperenhanced myocardium while simultaneously suppressing blood-pool signal.

绞股蓝多糖的分离纯化及红外光谱、气相色谱分析

目的:绞股蓝多糖的分离纯化及单糖组成的研究。方法:采用水提醇沉和DEAE52纤维素柱层析等方法,得精制绞股蓝多糖(GPM2)。利用红外光谱(IR)和气相色谱(GC)分析多糖的糖键结构和单糖的组成及摩尔比值。结果:DEAE52纤维素柱层析分离纯化多糖效果显著,得精制多糖(GPM2)。IR分析显示GPM2具有典型的多糖吸收峰。GC分析得出该单糖组成为鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖,摩尔比为3.23:7.71:1.00:2.29:2.88:14.84,其中半乳糖的含量最高。结论:分析绞股蓝多糖的结构和组成,对绞股蓝产品的功能和生产有着重大指导意义。