Isolation of translactone-containing triterpenes with thrombin inhibitory activities from the leaves of Lantana camara

Methanolic extracts prepared from the leaves of Lantana camara have been found to inhibit human thrombin. An assay, in which thrombin activity is measured as a function of clot formation from fibrinogen, was used to guide the fractionation and purification of five principal active constituents (1-5), which were all characterized as 5,5-trans-fused cyclic lactone-containing euphane triterpenes.     

English teaching in the Italian medical faculties: results of a survey

BACKGROUND: Although a compulsory examination in medical English has been present in the medical degree curriculum in Italy since 1990, guidelines indicating what should be learnt and suggesting some means of overcoming the various problems this entails are still lacking. OBJECTIVE: To investigate the main features of teaching English in the Medical Faculties and enquire into how the various problems are solved in the individual English teaching units. METHOD: A questionnaire addressing the above issues was sent out to all the Italian Universities with a Medical Faculty. RESULTS: The first finding of our survey was that response was very poor: less than 30% of the survey volunteered any reply. Within the very reduced sample which responded, there was a high degree of variation among the solutions adopted, although the underlying problems were perceived to be much the same throughout Italy. CONCLUSIONS: The general objective of the English course for medicine should be more precisely defined, together with a series of specific minimum skills the student should possess to pass the final examination. A closer collaboration among the English teaching units might help to standardize these requirements, improve the quality of the teaching and hence the level of proficiency in English for the specific purpose of medical practice.     

Cortical variations of the dimension of correlation in children with attention deficit hyperactivity syndrome

INTRODUCTION AND OBJECTIVE: The syndrome of deficient attention and hyperactivity affects approximately 5% of children of school age. Clinically it is characterized by deficient attention, impulsiveness and excessive motor activity. Developments in nonlinear dynamic theory have made it possible to think of modelling cerebral activity as a dynamic system of chaotic type. One the most widely standardized measurements is the dimension of correlation (D2). In this paper we study the electroencephalographic traces of a control group of 9 healthy children and another group of 19 children with the syndrome of deficient attention, at rest and whilst carrying out a visuomotor task (Test of perception of differences). MATERIAL AND METHODS: The dimension of correlation was estimated for both groups. Statistical comparison was made between the cortical distributions of the D2 between both types of recordings and between both groups. RESULTS: The children with lack of attention showed a larger number of activated cortical areas than those of the control group when carrying out the same task. However, during the resting state there were no differences in the D2 between the control children and the children with deficient attention. The indicates that both groups have the same basal level of activation. CONCLUSION: The dimension of correlation is a method which permits the demonstration of an increase in neuronal activity in the stimulated areas, in this case in the occipital region.     

Characterization of a negative cis-acting DNA element regulating the transcription of CYP2B1/B2 gene in rat liver

Polymeric films were deposited from hydroxyethylmethacrylate (HEMA) plasma on non-woven poly(butyleneterephtalate) (PBT) filter materials. To test the effect of deposition conditions on surface properties, film were deposited using a constant monomer flow rate and a discharge power ranging from 40-100 W. Surface composition and surface energetics were evaluated by Electron Spectroscopy for Chemical Analysis (ESCA) and contact angle measurement, respectively. Albumin (Alb) and fibrinogen (Fg) adsorption from single protein solutions to the plasma-coated filters was measured. Results illustrate the marked effects of the deposition condition on the surface composition, the surface field of forces, and the protein adsorption behavior. The latter is modeled by the application of the Good-van Oss-Chaudhury theory of Lewis acid-base contribution to interfacial energetics. Materials endowed with widely different properties are obtained from the same monomer and different deposition conditions, a result that must be taken into account both in the production step, to assure constant quality, and in the development of specifically tailored materials.     

Field study of the removal of linear alkylate sulfonate detergents by the activated sludge process

Field evaluation of the removal of linear alkylate sulfonate (LAS) detergents by the activated sludge process was carried out at the Kettle Moraine Boys’ School near Plymouth, Wisconsin. The procedures and controls afforded by the school’s central supply system along with its new and well-operated “extended aeration” activated sludge plant, provided an excellent arrangement for controlled field comparison of the removal of LAS and ABS (alkyl benzene sulfonate) material. In addition, the sewage treatment plant was operated intentionally to produce poor results in order to observe the effects of such conditions on removals. Previous work showed that, with products containing ABS in use at the school, removals of methylene blue active substance could be expected to fall in the region of 75 to 85%. Removals with LAS material in use at the school were shown to be from 95 to 99% as long as the plant was operated satisfactorily. Further, the results showed that there was a strong correlation between LAS removal and BOD removal with a one to one slope. The results support the conclusion that for biological treatment processes, the removal of LAS material corresponds to the removal of BOD.     

Crack Characterization Method with Invariance to Noise Features for Eddy Current Inspection of Fasterner Sites

There is a need for research in eddy current (EC) nondestructive evaluation (NDE) to improve the reliability to detect, locate and size cracks around fastener sites in multi-layer structures while minimizing the overall cost of inspection. The objective of this work is to develop feature extraction and classification algorithms for crack characterization with invariance to noise features for eddy current inspection of fastener sites. Model-based parametric studies were first performed to explore potential features under a wide array of crack, noise and material conditions. Through these studies, several features were identified to have some invariance to the characteristic asymmetric response due to gaps between the fastener and hole, probe liftoff variation, and probe skew. In particular, a promising feature with noise invariance to all non-flaw conditions considered in this study was found through investigating changes in the eddy current response along a circumferential direction in an annulus region away from the hole center. To obtain a measure of this localized crack feature, an approach was developed using a fit of a characteristic function to the data through nonlinear least squares estimation. A model-based optimization approach was also implemented to evaluate the best signal processing algorithm design to distinguish between several classes of crack size. Using this approach, an optimized measure was found to be well correlated with subsurface crack size and insensitive to noise conditions included in this study.     

Chemical Ecology of the host searching behavior in an Egg Parasitoid: are Common Chemical Cues exploited to locate hosts in Taxonomically Distant Plant Species?

Parasitoids are known to exploit volatile cues emitted by plants after herbivore attack to locate their hosts. Feeding and oviposition of a polyphagous herbivore can induce the emission of odor blends that differ among distant plant species, and parasitoids have evolved an incredible ability to discriminate them and locate their hosts relying on olfactive cues. We evaluated the host searching behavior of the egg parasitoid Cosmocomoidea annulicornis (Ogloblin) (Hymenoptera: Mymaridae) in response to odors emitted by two taxonomically distant host plants, citrus and Johnson grass, after infestation by the sharpshooter Tapajosa rubromarginata (Signoret) (Hemiptera: Cicadellidae), vector of Citrus Variegated Chlorosis. Olfactory response of female parasitoids toward plants with no herbivore damage and plants with feeding damage, oviposition damage, and parasitized eggs was tested in a Y-tube olfactometer. In addition, volatiles released by the two host plant species constitutively and under herbivore attack were characterized. Females of C. annulicornis were able to detect and significantly preferred plants with host eggs, irrespectively of plant species. However, wasps were unable to discriminate between plants with healthy eggs and those with eggs previously parasitized by conspecifics. Analysis of plant volatiles induced after sharpshooter attack showed only two common volatiles between the two plant species, indole and β-caryophyllene. Our results suggest that this parasitoid wasp uses common chemical cues released by many different plants after herbivory at long range and, once on the plant, other more specific chemical cues could trigger the final decision to oviposit.

     

The puncture and catheterization of the peripheral vessels using ultrasonic scanning

1% acetylcholine (5.5 10 M--acetylcholine chloride) applied directly to the cortex of conscious non-immobilized rabbits was established to produce neuroglial reaction in motor area. Following 30 min long application the number of astrocytes was significantly increased. Application lasting for 2 hrs resulted in a reverse effect. The above-mentioned changes were observed in surface and deep cortical layers. They were functional and could be attributed to the cell tinctorial properties.