Adhesiveness of human uterine epithelial RL95-2 cells to trophoblast: rho protein regulation

Embryo implantation involves adhesion of trophoblast cells to the epithelial lining of the endometrium. Using an in-vitro model to simulate this initial interaction, we previously reported that attachment of human trophoblast-like JAR spheroids to human uterine epithelial RL95-2 cells provokes a Ca(2+) influx in RL95-2 cells depending on apically localized integrin receptors. Here, we demonstrate that adhesiveness of RL95-2 cells for JAR spheroids, measured by a centrifugal force-based adhesion assay, is dependent on Rho GTPases, most likely RhoA. Cellular expression and distribution of RhoA were studied by fluorescence confocal microscopy, focusing on the localization of RhoA and F-actin within the adhesion sites between JAR and RL95-2 cells. Contact areas contained high amounts of RhoA and F-actin fibres near the plasma membrane. To determine whether Rho GTPases may influence JAR cell binding, we treated RL95-2 cells with Clostridium difficile toxin A, which specifically inactivates Rho GTPases. Toxin A treatment changed the subcellular distribution of endogenous RhoA in RL95-2 cells and altered RhoA and F-actin colocalization. Adhesion of JAR spheroids to RL95-2 cells treated with toxin A was largely suppressed. These data indicate that Rho GTPases, most likely RhoA, play an important role in uterine epithelial RL95-2 cells for trophoblast binding, and suggest that RhoA may be involved in local signalling cascades during early embryo implantation in vivo.     

Effect of cholesterol feeding on tissue lipid perioxidation, glutathione peroxidase activity and liver microsomal functions in rats and guinea pigs.

The effect of cholesterol feeding on liver and aortic nonenzymatic lipid peroxidation and glutathione peroxidase activities, and on liver microsomal NADPH-dependent lipid peroxidation, codeine hydroxylation and cytochrome P-450 levels was examined in rats and guinea pigs. One percent cholesterol was added to a casein-sucrose-soybean oil basal diet for rats or a stock diet with 2% soybean oil for guinea pigs. The effect of vitamin E and cholestyramine was also examined in some experiments. Cholesterol feeding increased the rate of lipid peroxidation in liver and aortic homogenate both in rats and guinea pigs when fed non-vitamin E supplemented basal diets. Vitamin E supplementation prevented the increase in the aorta, but not as completely in the liver in rats, while the reverse was true in guinea pigs. The effect of cholestyramine was dependent on the level of vitamin E in the diet. Cholesterol feeding decreased glutathione peroxidase activities in rats and guinea pigs. In guinea pigs, cholesterol feeding also markedly decreased liver microsomal NADPH-dependent lipid peroxidation, codein hydroxylation and cytochrome P-450 levels especially when fed non-vitamin E supplemented basal diets. In rats, cholesterol feeding reduced liver microsomal NADPH-dependent lipid peroxidation and in some cases, increased microsomal codeine hydroxylation activities, but had no effect on microsomal cytochrome P-450 levels. Vitamin E supplementation increased liver and serum cholesterol levels in guinea pigs, but had no such effect in rats. Results of this study indicate that cholesterol feeding can result in various metabolic alterations in rats and guinea pigs. The implication of these alterations in atherogenesis requires further investigations.     

Vertebrobasilar ischemia. Value of Doppler ultrasound in the acute phase]

We prospectively studied patients with acute vertebrobasilar ischaemia to assess the value of Doppler ultrasound compared to cerebral angiography during initial evaluation. Doppler ultrasound was diagnostic in 11 of 14 patients (79%). Transcranial ultrasonic examination yielded important information in addition to extracranial findings in 8 of 11 patients. Depending on the underlying vascular pathology, Doppler ultrasound proved to be a useful screening instrument to support acute management of vertebrobasilar ischaemia. With regard to clinical symptoms and ultrasonic findings, practical consequences for diagnostic evaluation are proposed.     

Degree of fractal behavior as a diagnostic aid in quantitative image analyses.

PURPOSE: Multiple strategies in diagnoses of different diseases from images can include their histogram analyses. Any fractal behavior in the latter is to be quantified as to extent here, with a view toward contributing to a diagnostic process. PROCEDURE: One tool in quantitative image analyses is the fractal dimension D of the pixel histogram, a measure of self-similarity over various scales in a fitted power-law behavior of pixel intensity cumulative probability distribution. Proposed and developed here as diagnostic markers are features of its determination process that indicate to what extent there is fractal behavior. One of these is the curvature c that exists in log-log plots used for extracting the fractal exponent D of power-law behavior. RESULTS: Specific implementations are given both for a general lognormal pixel intensity distribution and for lung images. Both Ds and cs are determined for: normals, pulmonary embolism, cystic fibrosis, as well as a theoretical lognormal distribution. It is shown that D and heterogeneity described by a standard deviation are reciprocally related and not typically independent markers. The added independent information from c has possibilities of assisting in discrimination of normal and pathologic conditions, such as in lung diseases. CONCLUSION: In addition to a histogram's fractal dimension itself, there are indications that measures of the degree of fractal behavior may also hold promise in image diagnoses.     

A Weight Index for the Standardized Uptake Value in 2-Deoxy-2-[F-18]fluoro-<Emphasis Type="SmallCaps">d</Emphasis>-glucose-Positron Emission Tomography

Introduction Known errors in the standardized uptake value (SUV) caused by variations in subject weights W encountered can be corrected by lean body mass or body surface area (bsa) algorithms replacing W in calculations. However this is infrequently done. The aims of the work here are: quantify sensitivity to W, encourage SUV correction with an approach minimally differing from tradition, and show what improvements in the SUV coefficient of variation (cv) for a population can be expected. Methods Selected for analyses were 2-deoxy-2-[F-18]fluoro-d-glucose (FDG) SUV data from positron emission tomography (PET) and PET/computed tomography (CT) scans at the University of Tennessee as well as from the literature. A weight sensitivity index was defined as −n=slope of ln(SUV/W) vs. lnW. The portion of the SUV variability due to this trend is removed by using the defined , or a virtually equal SUV _m using , with Q and ID being tissue specific-activity and injected dose. measures performance. Adapting to animal studies’ tradition, is preferred over the conventional . Results For FDG in adults from averaging over most tissues. In children, however, . Tissues have the same index if their influx constants are independent of W. Suggested, therefore, is a very simplified , which is dimensionless and keeps the same population averages as traditional SUVs. It achieves . Hence, for cv’s of SUVs below ∼1/3 improvements over tradition are possible, leading to F’s<0.95. Accounting additionally for height, as in SUV_bsa, gives very little improvement over the simplified approach here and gives essentially the same F’s as SUV _m . Conclusions Introduced here is a weight index useful in reducing variability and further understanding the SUV. Addressing weight sensitivity is appropriate where the cv of the SUVs is below about 1/3. Proposed is the very simple approach of using an average of an adult patient’s weight and ∼70 kg for FDG SUV calculations. Unlike other approaches the dimensionless population average of SUV _m s is unchanged from tradition.     

Transcranial Doppler evaluation of common and classic migraine. Part II. Ultrasonic features during attacks

Transcranial Doppler (TCD) examinations were performed in 13 patients with common and 5 patients with classic migraine during attacks and compared to TCD findings during the headache-free period. Two distinct patterns of flow changes were detected to distinguish common from classic migraine on the basis of TCD findings. During attacks, patients with common migraine exhibited reduction of flow velocities associated with an increase of pulse wave amplitudes. Vascular bruits that were heard during the headache-free interval often disappeared. Opposite changes were found in attacks of classic migraine during the headache phase with increase of flow velocities, decrease of pulsatility and more prominent or newly appearing bruits. These findings were often diffuse and did not appear to correlate with side of headache or side of neurological aura. Uniform changes occurred in the cervical internal carotid artery and the basal cerebral arteries in either form of migraine. We propose that these changes represent caliber fluctuations of the large arteries, suggesting vasodilatation during attacks of common migraine and vasoconstriction during attacks of classic migraine. We do not intend to imply a casual role of these preliminary findings in migraine pathogenesis, but we suggest that TCD be used in combination with other methods to study vascular changes in migrainous disorders.     

Improving reproducibility of VEP recording in rats: electrodes,stimulus source and peak analysis

The aims of this study were to evaluate and improve the reproducibility of visual evoked potential (VEP) measurement in rats and to develop a mini-Ganzfeld stimulator for rat VEP recording. VEPs of Sprague–Dawley rats were recorded on one randomly selected eye on three separate days within a week, and the recordings were repeated three times on the first day to evaluate the intrasession repeatability and intersession reproducibility. The VEPs were recorded with subdermal needle and implanted skull screw electrodes, respectively, to evaluate the effect of electrode configuration on VEP reproducibility. We also designed a mini-Ganzfeld stimulator for rats, which provided better eye isolation than the conventional visual stimuli such as flash strobes and large Ganzfeld systems. The VEP responses from mini-Ganzfeld were compared with PS33-PLUS photic strobe and single light-emitting diode (LED). The latencies of P1, N1, P2, N2, and P3 and the amplitude of each component were measured and analysed. Intrasession and intersession within-subject standard deviations (Sw), coefficient of variation, repeatability (R₉₅) and intraclass correlation coefficient (ICC) were calculated. The VEPs recorded using the implanted skull electrodes showed significantly larger amplitude and higher reproducibility compared to the needle electrodes (P < 0.05). The mini-Ganzfeld stimulator showed superior repeatability and reproducibility in VEP recording. The intra/intersession ICCs of latency were 0.85/0.70 for mini-Ganzfeld, 0.72/0.62 for PS33-PLUS and only 0.59/0.42 for single LED. The latencies of the early peaks (N1 and P2) demonstrated better reproducibility than the later waves. The mean intrasession and intersession ICCs were 0.96 and 0.86 for the early peaks. Using a combination of skull screw electrodes, mini-Ganzfeld stimulator and early peak analysis, we achieved a high reproducibility in the rat VEP measurement. The latencies of the early peaks of rat VEPs were more consistent, which may be due to their generation in the primary visual cortex via the retino-geniculate fibres.