Methanol extract of Terminalia superba induces endothelium-independent relaxation of rat thoracic aorta

Terminalia superba is highly regarded in some parts of Cameroon in traditional medical practice. We have studied the vasorelaxant effects of the stem bark methanol extract of T. superba on rat vascular smooth muscle. The results demonstrated that T. superba extract provoked a time-dependent relaxation of aortic rings precontracted with norepinephrine (10(-6) M). The vasorelaxant effect of the plant extract was not affected by endothelium removal or by pretreatment with indomethacin or N(W)-nitro-Larginine methyl ester (L-NAME). T. superba extract did not significantly, affect the contraction induced by 30 mM or 60 mM KCl as compared to those induced by NE. Relaxations elicited by T. superba extract were markedly reduced by glibenclamide, a putative blocker for K(ATP) channels and by tetraethylammonium, the non-specific K+ channel inhibitor. T. superba caused a time- and concentration-dependent relaxation of the rat aortic rings that were inhibited by charybdotoxin and iberotoxin but not by apamin. These finding indicate that T. superba extract at least partially relaxes the rat aorta by activating K+ channels, mainly KATP channels and large-conductance Ca2+ -activated K+ channels in rat aorta.

Measurement of cardiac ventricular volumes using multidetector row computed tomography: comparison of two- and three-dimensional methods

This study compared a three-dimensional volumetric threshold-based method to a two-dimensional Simpson's rule based short-axis multiplanar method for measuring right (RV) and left ventricular (LV) volumes, stroke volumes, and ejection fraction using electrocardiography-gated multidetector computed tomography (MDCT) data sets. End-diastolic volume (EDV) and end-systolic volume (ESV) of RV and LV were measured independently and blindly by two observers from contrast-enhanced MDCT images using commercial software in 18 patients. For RV and LV the three-dimensionally calculated EDV and ESV values were smaller than those provided by two-dimensional short axis (10%, 5%, 15% and 26% differences respectively). Agreement between the two methods was found for LV (EDV/ESV: r=0.974/0.910, ICC=0.905/0.890) but not for RV (r=0.882/0.930, ICC=0.663/0.544). Measurement errors were significant only for EDV of LV using the two-dimensional method. Similar reproducibility was found for LV measurements, but the three-dimensional method provided greater reproducibility for RV measurements than the two-dimensional. The threshold value supported three-dimensional method provides reproducible cardiac ventricular volume measurements, comparable to those obtained using the short-axis Simpson based method.

[Pleural mesothelioma: imaging contribution]

Imaging plays an essential role in management of patients of with pleural mesothelioma. In this article, we discuss the respective roles for ultrasonography, computed tomography, magnetic resonance imaging, and positon emission tomography for the diagnosis, staging, and postherapeutic evaluation of pleural mesothelioma.

Effect of temperature and bacteria on sporulation of Phytophthora alni in river water

In order to evaluate the role of river water on the spread of the alder disease caused by Phytophthora alni, water samples were collected at different periods of the year 2004 in two rivers displaying contrasting biological quality indices. Sporangia were produced from isolates of P. alni belonging to the three subspecies, at the river temperature (between 8 and 15 degrees C according to the sampling period). The sporulation efficiency was evaluated according to a scale of 0-9, based on the amount of sporangia produced on mycelium plugs immersed in the water for two days. Sporulation was also evaluated in river water sterilised by filtration. The amount of sporangia increased with the water temperature for both rivers, regardless of the biological quality. No sporangium was produced at the lowest temperature (8 degrees C). Sterilisation of the water drastically reduced the sporangia-stimulating effect for most of the P. alni isolates.

Liposarcoma of the pleural cavity. An exceptional tumour

Primitive liposarcomas of the pleura are exceptional tumours. We report a new case of primitive liposarcoma of the pleura revealed by chest pains in a 50 year old man. Computed tomography showed a large fat density mass in the left pleural cavity. Surgical resection was performed, completed with adjuvant radiotherapy. Few reports are available in the literary world. We present our case, review previously reported cases and discuss treatment.

Brain abscess caused by Nocardia cyriacigeorgica in a patient with human immunodeficiency virus infection

Nocardia cyriacigeorgica is a recently characterized species within the genus of Nocardia. We report a brain abscess, following a primary pulmonary colonization, due to this species in a human immunodeficiency virus-infected patient. This case confirms that isolation of Nocardia in sputum is associated with a high risk of disseminated infection in immunocompromised patients.

CT angiography of intrahepatic portal aneurysm

We report a case of an asymptomatic portal vein aneurysm diagnosed at ultrasonography and documented with multidetector computed tomography. We describe the features found at quadriphasic multidetector computed tomography with three-dimensional computed tomographic angiography.

Reproducibility of multi-detector spiral computed tomography in detection of sub-segmental acute pulmonary embolism

The aim of this study was to evaluate the inter-observer and intra-observer agreement of the diagnosis of sub-segmental acute pulmonary embolism (PE) in an inpatient population explored by 16 slice multi-detector spiral computed tomography (MDCT). Four hundred consecutive inpatients were referred for MDCT for the clinical suspicion of acute PE. One hundred and seventy seven (44.2%) had a known cardio-respiratory disease at the time of examination. Inter-observer and intra-observer agreements for the diagnosis of acute PE and of sub-segmental acute PE were assessed blind and independently by three experienced readers and by kappa statistics. Seventy-five patients were diagnosed as having acute PE findings (19.5%), and clots were located exclusively within sub-segmental arteries in nine patients (12%). When clots were limited to sub-segmental or more distal branches of the pulmonary arteries, kappa values were found to be moderate (0.56) to very good (0.85) for the diagnosis of sub-segmental acute PE, whereas for the diagnosis of acute PE in the whole population, kappa values ranged from 0.84 to 0.97. Intra-observer agreement was found to be perfect (kappa=1). MDCT is a reproducible technique for the diagnosis of sub-segmental acute PE as well as for acute PE. In this inpatient population, sub-segmental acute PE was not a rare event.

Behaviour of dioxin in pig adipocytes

Due to their lipophilic properties, dioxins can be integrated into the lipidic vacuole of adipocytes (fat cells). The aim of this study was to determine the kinetics of incorporation and release of 3H-labelled palmitic acid and 14C-labelled 2,3,7,8-TCDD in isolated adipocytes from pigs. The incorporation of 2,3,7,8-TCDD and palmitic acid was found to be concomitant under conditions of lipogenesis, under the effect of increasing quantities of insulin and in the presence of glucose. Release of these two compounds was found to be dependant on a lipolytic agent (epinephrine). These results suggest the risk of a strong increase of 2,3,7,8-TCDD, induced by lipolysis, in the blood of animals or humans previously exposed to this dioxin.

Metabolism of [14C]-2,4,6-trinitrotoluene in tobacco cell suspension cultures

The metabolism of 2,4,6-trinitrotoluene (TNT) was investigated in tobacco cell suspension cultures amended with [14C]-TNT. Five metabolites were purified and characterized. Temporal evolution of metabolites was monitored during a 120 h incubation period. Metabolites structure was identified by acid and enzymatic hydrolysis, followed by electrospray ionization mass spectrometry and 1H and 13C NMR spectroscopy analyses. The majority of metabolites were conjugates formed by glycose conjugation on the hydroxylamine group of either 2-hydroxylamino-4,6-dinitrotoluene (2-HADNT) or 4-hydroxylamino-2,6-dinitrotoluene (4-HADNT), which led to monoglycoside then to diglycoside. Various diglycosides were observed with gentiobioside or sophoroside formation. Bound residues represented a small fraction (<10% of initial 14C) irrespective of the interval after TNT amendment. Free ADNT was detected only in the medium. This study highlights the central role played by HADNT in the TNT metabolic pathway in tobacco cell suspension culture, and the key role of these compounds and of glycosyltransferases in TNT phytoremediation processes.

Short Communication: Study of Mammary Epithelial Role in Polycyclic Aromatic Hydrocarbons Transfer to Milk

Food would appear to be one of the main routes for animal and human contamination with polycyclic aromatic hydrocarbons (PAH). Many studies have shown the presence of PAH in milk and dairy products, suggesting that these foods can represent a part of this contamination. Our work aimed at defining, in vitro, the mammary barrier role in PAH transfer to milk. MAC T cells were cultivated on permeable filters to measure transepithelial permeability of 14C labeled benzo[a]pyrene (BaP), pyrene (Pyr), and phenanthrene (Phen), which differed in their physicochemical properties. The results showed that only 2 molecules, Phen and Pyr, were able to cross mammary cell layers. Phenanthrene radioactivity appeared more quickly in apical media, and its level after a 6-h exposure was 1.3 times higher than for Pyr and 7.7 times higher than for BaP. These findings suggested that mammary epithelium could play a key role in the selective transfer of PAH from food to milk.

Proteolysis in milk during experimental Escherichia coli mastitis

This work consisted of the intramammary infections (IMI) of 8 heifers by high doses of Escherichia coli to study both the proteolytic activity in milk and the resulting peptides. Therefore, a milking kinetic has been followed, and several parameters have been studied, such as proteose peptones (PP) fraction (quantitative and qualitative changes), plasmin activity (PA), milk somatic cell count (SCC), and bacterial count. A qualitative study of milk proteins and PP was performed by sodium dodecyl sulfate-PAGE, and the peptides recovered in PP during the acute phase of inflammation were amino-terminal micro-sequenced. A BSA increase in milk over time supported the hypothesis of an increase in the permeability of the epithelial barrier. A significant increase in PP content, considered to be an indicator of proteolysis, was observed from postinfusion hours (PIH) 12 to 48. Both the E. coli bacterial count and the SCC increased from PIH 3 to 216. Plasmin activity was increased noticeably from PIH 15 to 24. The respective increases in SCC, bacterial count, and PA suggest their involvement in a global mechanism responsible for the increase in proteolysis in milk after E. coli challenge. Somatic cell count and E. coli may be involved from PIH 3 to 216, and PA involvement might be highlighted during the maximum proteolysis, from PIH 15 to 24. A qualitative study of PP fraction by electrophoresis revealed the apparition of 5 peptide bands: P1 and P2 previously recovered during the lipopolysaccharide challenge, and E1 (27.0 kDa), E2 (15.5 kDa), and E3 (9.0 kDa) were specific to E. coli challenge; E1, E2, and E3 contained casein fragments. The roles played by leukocytes and E. coli are discussed.

Metabolic fate of [14C]-2,4-dichlorophenol in macrophytes

The metabolic fate of 2,4-dichlorophenol (DCP) was investigated in six macrophytes representing different life forms. Salvinia natans and Lemna minor were chosen as surface-floating plants, Glyceria maxima and Mentha aquatica as emergent species and Myriophyllum spicatum and Hippuris vulgaris as submerged aquatic plants. After uptake of a [U-phenyl-14C]-DCP solution followed by a 48 h water chase, whole plants (L. minor, S. natans) or excised shoots were harvested and aqueous extracts were analysed by high performance liquid chromatography (HPLC). Metabolites were then isolated, submitted to enzymatic or chemical hydrolyses and characterised by electrospray ionisation-mass spectrometric analyses. Whereas DCP monoglucosides or more complex monoglucoside esters, either malonyl or acetyl, were found in most species, an unusual glucosyl-pentose conjugate was identified as the DCP major metabolite in L. minor and G. maxima. Our results showed for the first time the ability of five macrophytes to uptake and metabolise DCP and the characterisation of their metabolic pathways of DCP biotransformation.

Severe peritonitis due to Balantidium coli acquired in France

The case reported here concerns an alcoholic pork-butcher who presented with severe colitis with peritonitis, caused by the only ciliate protozoan capable of infecting humans, Balantidium coli. This parasite is common in a variety of domestic and wild mammals, mainly pigs; however, its prevalence rate in humans is very low--particularly in industrialised, northern countries, including France. The infection is most frequently acquired by ingesting food or water contaminated by pig faeces, and it may be asymptomatic or may cause acute diarrhoea. Specific antibiotic treatment is efficacious, and it is important to consider the risk of this parasitic disease in susceptible patients presenting with bloody diarrhoea.

Effects of different levels of gum arabic, low methylated pectin and xylan on in vitro digestibility of beta-lactoglobulin

Plant hydrocolloids used in the food industry to improve texture and stability of food, such as dairy products, can reduce protein digestibility and, consequently, modify the bioavailability of amino acids. We studied the in vitro hydrolysis at 37 degrees C of beta-lactoglobulin (beta-lg) in mixed dispersions containing either gum arabic or low-methylated pectin or xylan at levels of 0, 1, 10, 20, 30, and 50% weight. Proteolysis used either pepsin alone by progressive reduction of pH during proteolysis or pepsin followed by trypsin and chymotrypsin in two different dialysis bags with a molecular weight (MW) cutoff of 1000 or 8000 Da. Results showed that beta-lg was almost resistant to pepsin digestion and that the three plant hydrocolloids inhibited significantly beta-lg digestibility as determined using dialysis bag with a 1000-Da MW cutoff. Among the three polysaccharides used, xylan showed a digestibility decrease greater than that obtained with gum arabic and low-methylated pectin. On the other hand, no significant effect of polysaccharides on the in vitro beta-lg digestibility was detected using the dialysis bag with an 8000 Da MW cutoff. This mainly suggests that peptides with MW in the range 1000 to 8000 Da may interact with polysaccharides more than peptides and proteins with a greater molecular weight to decrease the protein digestibility, and that the nature of the polysaccharides plays a role in the interaction.

Variations of trans octadecenoic acid in milk fat induced by feeding different starch-based diets to cows

The impact of starch sources differing in their velocities of ruminal degradation on the milk fat of dairy cows was studied. The animals received diets containing a slowly degradable (potatoes) or rapidly degradable (wheat) starch concentrate (40% of the dry matter) in a total mixed diet. Milk fat was the only animal performance factor affected: Cows produced significantly less milk fat when fed the wheat diet than the potato diet (-3.3 g/kg, -122 g/d; P < 0.05). With the wheat diet, milk fat was poorer in short-chain FA and richer in unsaturated long-chain FA, especially in trans octadecenoic acid (4.4 vs. 2.7% of the total FA, P < 0.05). A very large increase in the isomer trans-10 18:1 (+1.46% of the total FA) was observed. Because no difference in volatile FA concentrations in the rumen was revealed, the increase in trans octadecenoic acids, and particularly the isomer trans-10 18:1, was associated with the larger postprandial drop in ruminal pH with wheat. Similar concentrate levels and FA profiles in both diets indicated that the decrease in milk fat was due to changes in the ruminal environment. Quicker degradation of wheat starch, and hence a greater drop in pH with this diet associated with the absence of any effect on volatile FA, strengthen the hypothesis developed in the literature of enzyme inhibition via increased levels of trans octadecenoic acids, especially the trans-10 isomer. Hence, milk fat can be decreased with rapidly degradable starch sources and not only with high levels of concentrates in the diet or added fat. More detailed work is necessary to elucidate the microorganisms involved and to determine whether metabolic pathways similar to those reported for high-concentrate diets are involved.

Screening of nonpolyenic antifungal metabolites produced by clinical isolates of actinomycetes

The purpose of this work was to screen clinical isolates of actinomycetes producing nonpolyenic antifungals. This choice was made to limit the problem of rediscovery of well-known antifungal families, especially polyenic antifungals. One hundred and ten strains were tested, using two diffusion methods and two test media, against three yeast species and three filamentous fungi. Among 54 strains (49%) showing antifungal activity, five strains belonging to the genus Streptomyces were active against all test organisms and appeared promising. These results indicate that clinical and environmental isolates of actinomycetes could be an interesting source of antifungal bioactive substances. The production of nonpolyenic antifungal substances by these five active isolates was investigated using several criteria: antibacterial activity, ergosterol inhibition, and UV-visible spectra of active extracts. One active strain responded to all three selection criteria and produced potentially nonpolyenic antifungal metabolites. This strain was retained for further investigation, in particular, purification, structure elucidation, and mechanism of action of the active product.Key words: actinomycetes, Streptomyces, clinical isolates, antifungal, non-polyene.