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Notes: Summary To assess the risk and possible mechanisms of hypoglycaemia during moderate exercise in Type I (insulin-dependent) diabetic patients receiving constant insulin infusion, five insulin-dependent male diabetic patients were exercised 18 h after their last meal and 30 h after their last injection of intermediate acting insulin. Intravenous insulin was initially delivered via a closed-loop infusion system programmed to lower mean blood glucose from 11.3 ± 1.8 to 4.8 ± 0.4 mmol/l over approximately 3.5 h. Blood glucose was then maintained at this level for 4 h. At this time, the closed-loop infusion was discontinued and replaced by an open-loop system. The average amount of insulin infused per min during the 4 h normoglycaemic closed-loop period was calculated and this amount was infused at a constant rate during both a 30 min period of exercise on a bicycle ergometer (approximately 65% maximum oxygen uptake) and a 30 min rest period which followed. Five nondiabetic males served as control subjects. Despite significantly higher free insulin concentrations (p 〈 0.05) and identical preexercise blood glucose concentrations, blood glucose rose during exercise only in the diabetic group (0.5 ± 0.2 mmol/l; p 〈 0.01). Changes in the serum concentrations of lactate, glycerol, glucagon, cortisol, non-esterified fatty acids and growth hormone were similar in the two groups and did not account for the increment of blood glucose in the diabetic patients. Beta-hydroxybutyrate concentrations were, however, higher in the diabetic patients at the onset of exercise (p 〈 0.01) and decreased significantly more than the control subjects during exercise. We conclude that exercise under these conditions in diabetic patients is not attended by hypoglycaemia.

Notes: Abstract. Aim and Design: In addition to a deficiency of endogenous prostaglandins due to inhibition of cyclo-oxygenase and a host of prostaglandin-mediated effects on mucosal protection, it has recently been proposed that neutrophil- and oxygen radical - dependent microvascular injuries may be important prime events that lead to mucosal injury induced by non-steroidal anti-inflammatory drugs. Therefore, we evaluated the role of oxygen free radicals in the pathogenesis of acute gastric ulceration induced by meloxicam, a preferential COX-2 inhibitor.¶Material: Studies were performed in Wistar rats.¶Treatment: Meloxicam was given by oral administration (3.75-30 mg/kg body weight).¶Methods: Determinations were made of gastric mucosal injury, xanthine-oxidase, myeloperoxidase and superoxide dismutase activities, as well as the effect of meloxicam on gastric prostaglandin synthesis (PGE2 levels) and glutathione homeostasis.¶Results: Oral administration of meloxicam dose-dependently (3.75-30 mg/kg) caused acute gastric haemorrhage erosions. The total area of gastric lesions increased with time until 24 hours after dosing. Xanthine-oxidase activity increased significantly after administration of the drug. Myeloperoxidase activity, as an index of neutrophil infiltration, as well as glutathione peroxidase, an important enzyme that scavenges lipid peroxides, were unaffected by meloxicam administration. In addition, superoxide dismutase activity, PGE2 and glutathione levels were significantly reduced.¶Conclusion: These results support the hypothesis that in addition to suppresion of prostaglandin synthesis, oxygen free radicals, probably derived via the action of xanthine oxidase, the decrease in superoxide dismutase activity, and the depletion of mucosal glutathione contribute to the pathogenesis of meloxicam-induced ulceration.

Notes: Abstract In the present report we studied the formation of severe gastric erosions produced in fasted rats by intragastric administration of piroxicam (PRX), an enolic acid-derived NSAID. The time course of gastric damage and the possible role of mucus secretion, endogenous sulphydryl compounds, changes of gastric vascular permeability and neutrophil infiltration in the development of PRX-induced gastric lesions were also investigated. PRX dose-dependently (1.25–20 mg/kg) caused acute gastric haemorrhagic erosion in the rat. The lesions increased with time until 9 hr after dosing. Mucus secretion did not change significantly with respect to the control group with 5, 10 and 20 mg/kg of PRX at different times (3 and 6 hours) of treatment. There was also no increase in the concentration of its components. In addition, oral pretreatment of the animals with PRX did not significantly change the amount of dye trapped in the stomach. In contrast, non-protein SH fraction was decreased after administration of PRX and MPO activity as an index of neutrophil infiltration was significantly increased. These results suggest that independently of the PRX dose, depletion of endogenous non-protein SH and neutrophil infiltration could play an important part in the pathogenesis of gastric mucosal injury induced by PRX.

Notes: Abstract. Objective and Design: The aim of the present study was to examine the effects of cinitapride, a novel prokinetic benzamide-stimulating gastrointestinal motility agent, on gastric secretion and ulceration in rats and elucidate some possible vascular and anti-oxidant mechanisms of such protection.¶Material: Male Wistar rats.¶Treatment: Cinitapride (CNT, Lab. Almirall, S.A.) (0.25, 0.5, and 1 mg/kg) and 5-hydroxytryptamine (5-HT, Sigma Chemical Co., St. Louis, MO, USA) (10 mg/kg), administered intraperitoneally (i.p.).¶Methods: Gastric ulceration was induced by instillation of 1 mL/100 g animal of 50% (v/v) ethanol in distilled water and by pylorus-ligated rat model. Gastric microvascular changes, and the activity of myeloperoxidase (as a marker of neutrophil infiltration) and glutathione peroxidase (an important enzyme in scavenging of lipid peroxides) were determined. The results were compared with those of 5-HT. The data were evaluated using Student’s t-test for paired data and the non-parametric Mann-Whitney U-test.¶Results: In 4 h pyloric-ligated animals, i.p. CNT did not significantly reduce the incidence of gastric mucosal damage, and no significant differences were found in the values of total volume and acidity. However, CNT caused a marked and dose-dependent reduction of haemorrhagic lesions induced by 50% v/v ethanol. These protective effects were specifically related to a reduction of neutrophil infiltration. CNT at the dose of 1 mg/kg raised the decreased glutathione peroxidase activity to the control level. In contrast, pretreatment with 5-HT worsened the ethanol-induced erosions, but did not significantly induce any gastric microvascular changes. However, the myeloperoxidase activity rose markedly and the glutathione peroxidase levels decreased significantly in the mucosa injured by 50% v/v ethanol.¶Conclusions: This study demonstrates a new gastroprotective feature of CNT that could be partly explained not only through reduction of neutrophil toxicity but also by an increased synthesis of free-radical scavenging enzymes such as glutathione peroxidase. Furthermore, it is likely that serotonergic-dependent mechanisms are also involved via 5-HT2-receptor blockade and 5-HT1 receptor activation.

Notes: Abstract The availability of fast and accurate sequencing procedures along with the use of PCR has led to a proliferation of studies of variability at the molecular level in populations. Nevertheless, it is often impractical to examine long genomic stretches and a large number of individuals at the same time. In order to optimize this kind of study, we suggest a heuristic procedure for detection of the shortest region whose informational content can be considered sufficient for significant phylogenetic reconstruction. The method is based on the comparison of the pairwise genetic distances obtained from a set of sequences of reference to those obtained for different windows of variable size and position by means of a simple index. We also present an approach for testing whether the informative content in the stretches selected in this way is significantly different from the corresponding content shown by the larger genomic regions used as reference. Application of this test to the analysis of the VP1 protein gene of foot-and-mouth-disease type C virus allowed us to define optimal stretches whose informative content is not significantly different from that displayed by the complete VP1 sequence. We showed that the predictions made for type C sequences are valid for type O sequences, indicating that the results of the procedure are consistent.

Notes: A detailed study of bipolar transport under forward-bias conditions is evaluated by Ensemble Monte Carlo simulation in two structures (p+n and pn+ junctions). The static characteristics of both structures are presented. In particular, this study focuses on a microscopic analysis of current fluctuations. A decomposition of the autocorrelation function of the total current fluctuations in electron, hole and crossed contributions is performed. In this way, the importance of each type of carrier in the spectral density of current fluctuations in both structures for a wide frequency range is determined. In the low frequency range, the presence of shot, thermal and excess noise was found. The Ensemble Monte Carlo method also permits ready evaluation of the noise equivalent temperature in both structures. © 1996 American Institute of Physics.

Notes: KTiOPO4 (KTP) samples heated in vacuum at temperatures in the 400–650 °C range show a broad optical absorption similar to that observed by H2 reduction. The position of the maximum depends on the reduction degree. The transparency of the sample is recovered by heating in air at high temperature (600 °C). Vacuum annealing leads to the reduction of Ti4+ to Ti3+ and also to the reduction of Fe, W, and Rh impurities present in the samples, as inferred from electron paramagnetic resonance measurements. X-ray irradiation at 15 K induces an optical absorption peaking at 585 nm. This absorption has been ascribed to the superposition of the 2T2→2E transition of Ti3+ in the two different Ti sites of the lattice. It is suggested that the absorption observed in vacuum-reduced samples consists of the overlapping of the latter contribution and a charge transfer band of Fe-Ti pairs. A loss of K and P ions has been observed after the annealing of KTP in vacuum at 800 °C forming a surface layer that scatters light. Moreover, the K and P loss decreases the optical absorption induced at lower temperature (T〈650 °C). © 1994 American Institute of Physics.

Notes: Bi12(GaxBi1−x)O19.5 (BGaO) films with thickness in the range 100–1000 nm have been deposited on (100) Y-stabilized zirconia (YSZ) and (100) Bi12GeO20 (BGO) substrates using a KrF excimer pulsed laser and polycrystalline targets with composition x=0.63–0.72. The laser power density threshold for ablation of the targets has been determined to be J0=4.8 J/cm2. A deposition rate of 0.03 A(ring)/pulse was found for the substrate-target distance (6 cm) and laser fluence (J=7 J/cm2) used. Transparent and crystalline films were obtained heating the substrate in the 450–550 °C range under 1.5×10−1 mbar of oxygen pressure. Films deposited on hot substrates have a Ga stoichiometry x=0.5 but a Bi content slightly lower than that corresponding to sillenite. Films deposited on YSZ show preferential orientation. From the x-ray diffraction results and the comparison of the ionic distributions, it has been concluded that the most likely orientation between both lattices is 〈310〉{130}BGaO(parallel)〈011〉{100}YSZ. A {100}BGaO(parallel){100}BGO epitaxy has been inferred from Rutherford backscattering analysis. On both substrates the films behave as step waveguides with refractive index close to the value determined in bulk BGaO. © 1996 American Institute of Physics.

Notes: Summary.  Factor V deficiency is a rare hereditary bleeding disorder. Currently, FV concentrates are not available, and the treatment of spontaneous bleeding or bleeding associated with invasive procedures is transfusion of fresh frozen plasma (FFP). However, FFP transfusion can lead to the development of inhibitor to FV, and is associated with several potential transfusion reactions including allergic reactions. We report a patient with congenital severe FV deficiency with repeated haemarthroses of a shoulder joint, and progressively severe allergic reactions to FFP transfusions. In addition, the patient also developed acute pulmonary oedema. Activated recombinant coagulation factor VII (rFVIIa) was used as an alternative haemostatic agent to FFP. We describe the use of rFVIIa in this patient during haemarthroses, synovectomy, and physiotherapy.

Notes: A study has been made of the effect of properties and composition of soils on the adsorption of ethofumesate. Adsorption isotherms of ethofumesate by agricultural and natural soils and by montmorillonite and humic acid were obtained. The correlations between the Freundlich K constants, and Kd distribution coefficients and the soil parameters were determined. Significant correlations (P〈0.05) were found between K and clay content and between Kd and smectite content for the agricultural soils but the correlation with organic matter content was of borderline or no significance.Considering the agricultural and natural soils together or the soils with an organic matter content 〉2%, a highly significant correlation was found between K and the organic matter content. According to the r2 determination coefficient, the organic matter content accounts for 88.4% of the variability in adsorption in the first case, and 92.2% in the second case. The log10 Kdom values of soils with an organic matter content 〉2% were similar and confirm the importance of the organic matter as a determinant parameter in the adsorption of ethofumesate by these soils. The adsorption of the herbicide by montmorillonite and humic acid confirmed the results obtained with the soils and point to the importance of the exchangeable cation nature of the samples and of the temperature in the adsorption process. Adsorption de l'éthofumesate dans des sols agri-coles et naturels L'effet des propriétés et de la composition du sol sur l'adsorption de l'ethofumesate a étéétudié. Les isothermes d'adsorption de 1'éthofumesate par des sols agricoles et naturels ainsi que par la montmorillonite et des acides humiques ont été déterminés. Les corrélations entre les caractéris-tiques du sol, les constantes de Freundlich K d'une part et les coefficients de distribution Kd d'autre part ont été déterminées. Des corrélations significatives (P〈0.05) ont été mises en évidence entre K et la teneur en argile ainsi qu'entre Kd et la teneur en smectite pour les sols agricoles mais la correlation avec la teneur en matisre organique etait tout juste ou non significative.Lorsqu'on considérait les sols agricoles et naturels ensemble ou les sols dont la teneur en matière organique est supérieure à 2%, une corrélation hautement significative existait entre K et la teneur en matière organique. Le coefficient de détermination r2 montre que la teneur en matière organique explique 88.4% de la vari-abilité de l'adsorption dans le premier cas et 92.2% dans le second cas. Le log10 Kdométait similaire pour les sols de teneur en matière organique 〉2%, ce qui confirme l'importance du paramètre matière organique dans l'adsorption de 1'ethofumesate par ces sols. L'adsorption de I'herbicide par la montmorillonite et les acides humiques a confirmé les résultats obtenus avec les sols et a montre 1'importance de la température du process et de la nature des cations d'échange des échantillons. Adsorption von Ethofumesat in Acker- and natürlichen Böden Bei der Untersuchung der Wirkung der Eigen-schaften und der Zusammensetzung von Böden auf die Adsorption von Ethofumesat wurden Adsorplions-Isothermen mit Acker- und natürlichen Böden sowie mit Montmorillonit und Huminsäure ermittelt. Die Korrelationen zwischen den Freundlich-Konstanten K sowie den Verteilungskoeffizienten Kd und den Bodenparametern wurden bestimmt. Signifikante Korrelationen (P〈0.05) wurden für K und den Tongehall und für Kd und den Smectit-Gehalt in Ackerböden gefunden, doch die Korrelation mit dem Gehalt an organischer Substanz war marginal oder nicht signifikant. Für Acker-und natürliche Böden insgesamt oder Böden mit einem Gehalt an organischer Substanz von 〉2% wurde eine hochsignifikante Korrelation zwischen K und dem Corg.-Gehalt gefunden. Das Bestimmtheitsmaß (r2) für die organische Substanz lag swischen 88.4% im ersten und 92.2% im zweiten Fall. Die log10Koc-Werte Böden mit einem Corg.-Gehalt von 〉2 % waren ähnlich und bestätigen die Bedeutung der organischen Substanz als bestimmenden Parameter für die Adsorption von Ethofumesat in diesen Böden. Die Adsorption des Herbizids an Montmorillonit und Huminsäure unterstreichen die an den Böden gewonnenen Ergebnisse und die Bedeutung der Kationen-Austauschfähigkeit der Proben.