Increases in insulin-like growth factor-1 level and peroxidative damage after gestational ethanol exposure in rats.

Ethanol exposure during pregnancy elicits profound detrimental developmental and behavioral effects such as reduced levels of insulin-like growth factor-1 (IGF-1) in the fetus. However, few reports have addressed its impact on postpartum dams. This study was designed to examine the influence of gestational ethanol exposure on postpartum maternal organ oxidative damage and IGF-1 level. Pregnant female rats were pair-fed from Day 2 of gestation until labor with control or ethanol (6.36% (v/v)) liquid diets and were sacrificed 6 weeks after parturition (ethanol withdrawn after parturition). There was no difference in body weight during or after the gestational period between the control and ethanol groups. Litter size was significantly less for ethanol-fed dams. One-week postnatal pup survival was significantly lower in the ethanol-fed (57.1%) than the control (97.8%) group. Liver and kidney tissue IGF-1 levels and mRNA were elevated in the ethanol-fed mothers, accompanied by hepatic but not renal oxidative damage, indicated by profound lipid peroxidation (measured by malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE)) and protein carbonyl formation. The levels of glutathione (GSH), glutathione disulfide (GSSG) and GSH/GSSG ratios in liver and kidney were not different between the ethanol-fed and control dams. Collectively, these data suggest that gestational ethanol exposure may lead to postpartum oxidative organ damage and a possible compensatory increase in organ IGF-1 levels.     

In Vivo and in vitro EPR oximetry with fusinite: A new coal-derived,particulate EPR probe

The peak-to-peak line width (LW) of the first derivative electron spin resonance (EPR) spectrum of the coal maceral fusinite is reversibly broadened by O₂. The extent of broadening per unit of partial pressure of oxygen (pO₂) is unusually large, exceeding that of nitroxides by almost two orders of magnitude. This paramagnetic properly of fusinite, combined with its very stable physicochemical properties and low toxicity, is shown to be of utility in the measurement of pO₂ in vitro and in vivo. Fusinite particles are endocytosed by Chinese hamster ovary (CHO) cells in vitro; this is useful for intracellular O₂ measurements with commercially available EPR spectrometers operating at 9.1-9.3 GHz. For measurement of oxygen in vivo using low frequency EPR (1.l-1.3 GHr), fusinite provides a sensitive and persistent means to measure pop in tissues. Particles implanted into the gastrocnemius muscle of NJ mice remained interstitially in the same position for months with undiminished sensitivity to pO₂ and no specific toxic effects.     

Simultaneous measurement of intracellular and extracellular oxygen concentrations using a nitroxide-liposome system

The concentration of oxygen within cells is important in many physiological and pathological processes, but such oxygendependent phenomena are generally studied as a function of the concentration of extracellular oxygen, due to a lack of suitable methods. Electron parmamagnetic resonance (EPR) oximetric techniques offer an attractive alternative to make such measurements. Previous EPR oximetric studies of extracellular-intracellular oxygen gradients have been hindered, however, by the fact that separate samples, prepared in slightly different ways, were required for individual measurements of extracellular and intracellular oxygen concentrations. In this study we demonstrate a technique that allows simultaneous measurement of intracellular and extracellular oxygen concentrations in a single sample: extracellular measurement is achieved using positively charged nitroxides encapsulated in liposomes, while intracellular oxygen is determined using a membrane-permeable nitroxide along with an extracellular broadening agent. Application of this system to the measurement of oxygen concentrations in suspensions of rat myoblast cells gave results which are consistent with nonsimultaneous measurements and which show substantial extracellular-intracellular oxygen gradients in these rapidly respiring cells.     

Nasal radioiodine activity: a prospective study of frequency, intensity, and pattern

The nose has been reported as a site of radioiodine accumulation on 131I whole-body scintigraphy. To determine the frequency, intensity, and pattern of nasal radioiodine accumulation, a prospective study was performed on 21 patients referred for 131I whole-body scintigraphy during a 26-mo interval. All patients were dosed with 5 mCi (18.5 MBq) of 131I p.o., and imaged 72 hr later. Ninety-five percent (20/21) of patients had nasal radioactivity greater than background, and in 75% (15/20) of positive patients the pattern of activity was round. Clinical follow-up of these patients has shown no evidence of tumor involvement in the nasal area. We conclude that nasal radioiodine activity is a normal finding. Radioiodine uptake in the nasal area, without clinical suspicion of metastatic disease, should not be considered a criterion for surgical intervention or radioiodine therapy.     

Magnetic resonance imaging of cerebrotendinous xanthomatosis

Cerebrotendinous xanthomatosis is a rare familial sterol storage disease with accumulation of cholestanol and cholesterol particularly in xanthomas, bile and brain. Magnetic resonance imaging is a useful modality for imaging the affected tissues. It contributes to the evaluation and management of the disease.     

5-单硝酸异山梨酯血药浓度测定及其在人的药代动力学

采用气相色谱-电子捕获检测法测定 5-单硝酸异山梨酯的血药浓度。样品经乙醚—正己烷混合溶剂提取,三氟醋酐进行衍生化后,用5% SE-30硅烷化玻璃填充柱分离,以硝酸异山梨酯为内标,⁶³Ni电子捕获检测器检测。此法操作简便,日内、日间误差分别小于4%和6.5%,平均回收率为99.62%±1.19%。在20～800ng·mL^-1血浆浓度范围内呈线性关系(γ=0.9995)。最低检测浓度为2.0ng·mL^-1。应用此法研究了10名健康志愿者单次口服20mg 5-单硝酸异山梨酯片后的药代动力学。     

Convergence of neural systems processing stimulus associations and coordinating motor responses

A sensory-sensory learning paradigm was used to measure neural changes in humans during acquisition of an association between an auditory and visual stimulus. Three multivariate partial least-squares (PLS) analyses of positron emission tomography data identified distributed neural systems related to (i) processing the significance of the auditory stimulus, (ii) mediating the acquisition of the behavioral response, and (iii) the spatial overlap between these two systems. The system that processed the significance of the tone engaged primarily right hemisphere regions and included dorsolateral prefrontal cortex, putamen, and inferior parietal and temporal cortices. Activity changes in left occipital cortex were also identified, most likely reflecting the learned expectancy of the upcoming visual event. The system related to behavior was similar to that which coded the significance of the tone, including dorsal occipital cortex. The PLS analysis of the concordance between these two systems showed substantial regional overlap, and included occipital, dorsolateral prefrontal, and limbic cortices. However, activity in dorsomedial prefrontal cortex was strictly related to processing the auditory stimulus and not to behavior. Taken together, the PLS analyses identified a system that contained a sensory-motor component (comprised of occipital, temporal association and sensorimotor cortices) and a medial prefrontallimbic component, that as a group simultaneously embodied the learning-related response to the stimuli and the subsequent change in behavior.