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L’induction de la néoglucogenèse intestinale (NGI) par des stratégies nutritionnelles ou génétiques protège de l’obésité et du diabète de type 2 en activant l’hypothalamus par une boucle nerveuse. Ce glucose néoglucogénique libéré dans la veine diminue la taille du repas suivant indépendamment du nerf vague. Ces effets sur la prise alimentaire sont mimés par une perfusion portale de glucose au même débit que la NGI. Cependant, les mécanismes liant détection, transmission et intégration du signal nerveux restent à caractériser.

MEAs with various cathode Pt loadings were elaborated and aged using a multiple-stressor accelerated stress test (AST) in a segmented PEMFC. The thinnest (lowest Pt loading) cathodes have lower initial activity, owing to larger oxygen reduction reaction hindrance and oxygen transport resistance. Although the lowest cathode Pt loadings initially degrade faster, the overall loss of ECSA at end-of-test is nearly similar whatever the cathode Pt loading, with no local heterogeneities of aging detected along the gas channels. The cathode Pt/C catalyst degrades mostly by Ostwald ripening (which seems more pronounced for lower cathode Pt loading) and nanoparticles agglomeration, owing to superficial carbon functionalization and related Pt crystallite migration: no consequent carbon corrosion is witnessed in this AST. Also, the oxidized Pt2+ions formed by Pt corrosion diffuse/migrate roughly in a similar manner through the membrane for all cathode Pt loadings, and are re-deposited by crossover H2close to the cathodemembrane interface. Overall, the mechanisms of Pt/C degradation are not depending on the cathode Pt loading for the chosen AST.Keywords: Proton exchange membrane fuel cells (PEMFC); Cathode catalyst layer (CL); Platinum loading; Durability.

Polyurethane (PU) nanocomposites filled with inorganic particles, aiming at the improvement of mechanical and thermal properties, are well known. Unlike previous work we describe here the combination of two fillers, synthetic talc (silico-metallic mineral particles-SSMMP) with distinct hydrothermal processes (SSMMP 7 h and 24 h) and organically-modified commercial clay (SPR), aiming towards development of new polyurethane ternary nanocomposites by in situpolymerisation. Fillers were added 3 wt.% of the mass of pristine polymer, with a ranging of weight proportions (75:25/25:75) of SSMMP and SPR. Results were compared to those for nanocomposites containing pure SSMMP and SPR fillers. Dispersion degrees and filler interactions with the polyurethane matrix were followed by FTIR, XRD, SEM, TEM and AFM techniques. Results showed that the fillers presented a good dispersion and were exfoliated/ well dispersed in the polyurethane matrix. Thermal and mechanical properties of nanocomposites were evaluated in comparison to the binary nanocomposites (PU/SSMMP 7 h, PU/SSMMP 24 h and PU/ SPR). All nanocomposites presented superior values of Young's modulus to that of pristine PU. Results evidenced that the blend of SSMMP and SPR fillers is an interesting strategy to improve thermal and mechanical properties of nanocomposites.

In this study, we evaluated in field trials the effects on non-target species, of transgenic corn producing the Cry1Ab toxin of Bacillus thuringiensis (Bt). In 1998, we collected Ostrinia nubilalis(Hübner) larvae from transgenic Btcorn (Novartis Hybrid 176) and non-Btcorn at four geographical sites. We found a significant variation in parasitism by the tachinids Lydella thompsoni(Herting) and Pseudoperichaeta nigrolineata(Walker) among sites, and more parasitism in non-Btthan in Btfields. The Bteffect did not vary significantly among fields. In 1999, we performed a field experiment at two sites, comparing the temporal abundance of non-target arthropods in Btcorn (Monsanto Hybrid MON810) and non-Btcorn. The non-target insects studied included the aphids Metopolophium dirhodum(Walker), Rhopalosiphum padi(L.) and Sitobion avenae(F.), the bug Orius insidiosus(Say), the syrphid Syrphus corollae(Meigen), the ladybird Coccinella septempunctata(L.), the lacewing Chrysoperla carnea(Stephens), thrips and hymenopteran parasitoids. For all species but one, the number of individuals varied greatly over the season but did not differ between the types of corn. The only exception was thrips which, at one site, was significantly more abundant in Btcorn than in non-Btcorn. However this difference did not remain significant when we took the multiple tests into account. Implications for pest resistance management, population dynamics and risk assessment are discussed.

La néoglucogenèse intestinale (NGI) est une fonction bénéfique dans l’homéostasie énergétique. Chez la souris, son induction par les fibres diminue le poids et la masse grasse, alors que son absence favorise la prise de poids, suggérant ainsi qu’elle pourrait moduler le métabolisme du tissu adipeux. Nous proposons que la NGI pourrait améliorer le bilan énergétique en modulant la thermogenèse du tissu adipeux brun (TAB), en impliquant son principal régulateur: le système nerveux sympathique (SNS).

OBJECTIVE: Chronic Q fever is seldom recognized; before 1989, only 234 cases had been reported in the literature. The 92 cases of chronic Q fever collected at the French National Reference Center for Rickettsioses from 1982 through 1990 represent the largest series ever reported. PATIENTS: The patients included in the study were diagnosed between July 31, 1982, and August 1, 1990, at the French National Reference Center for Rickettsioses as having chronic Q fever by the following criteria: presence of antibody against Coxiella burnetii phase I antigen at a titer greater than or equal to 800 for IgG and 50 for IgA by the indirect immunofluorescence test. Epidemiologic, clinical, laboratory, and treatment data were collected from 39 different collaborative hospitals throughout France. MAIN OUTCOME MEASURE: For each serologically selected patient, a computerized questionnaire was utilized to record 188 different items of demographic, epidemiologic, clinical, laboratory, and therapeutic data, which were analyzed. RESULTS: Chronic Q fever occurs more frequently in city dwellers than in rural inhabitants, and exposure to domestic ruminants and raw milk is an important feature. Immunocompromising conditions (20.2%) and underlying heart disease (88.4%) or vascular disease are the most important risk factors to consider in potential cases of chronic Q fever. The mortality in these patients with endocarditis was high (23.5%). The clinical spectrum of 84 patients included 57 cases of endocarditis, three cases of vascular prosthesis infection, three cases of aneurysmal infection, three cases of osteoarthritis, four cases with lung localizations, nine asymptomatic cases, three cases of hepatitis, and two cases with cutaneous forms of the disease. CONCLUSIONS: In patients with unexplained fever, negative blood cultures, and a history of underlying vascular or cardiac disease, Q fever should be considered.(Arch Intern Med. 1993;153:642-648)

One hundred febrile episodes in neutropenic (PMN < 500/mm3) patients were treated with Timentin alone or in combination with amikacin. The overall response rate in 87 episodes was 82.9% with Timentin alone and 84.5% with the combination. Eleven out of 15 patients with septicaemia were cured by Timentin alone and 12 out of 13 by the combination, a response rate of 73.3% and 92.4% respectively (not-statistically significant P = 1.307). The rates of superinfection were low. Few side effects occurred. Timentin is a useful antibiotic in the treatment of febrile neutropenic patients and was, in this study, as effective alone as in combination with an aminoglycoside in the initial therapy.

Light and electron microscopic studies were performed on neuromuscular biopsy specimens from 12 neurologically affected seropositive patients, 7 with the acquired immune deficiency syndrome (AIDS), 2 with AIDS-related complex, and 3 with no symptoms except for neuropathy. All patients had an axonal injury associated or unassociated with demyelination and peripheral neurogenic atrophy. Capillary lesions were consistently present, which seems to be a new finding. Moreover, tubuloreticular inclusions (TRIs) were found in endomysial (9 of 12 cases) and endoneurial (7 of 12 cases) vessels. Statistical analysis showed that TRIs in more than 20% of endomysial vessels correlated with a survival time shorter than 12 months (P = 0.028). Thus the quantification of TRIs seems to be one of the vital prognostic elements in this patient population.

The major surface antigen from the proliferative form ofToxoplasma gondii(P-30 or SAG-1) was chosen as a target for exploration ofToxoplasma gondiireactivation in sera from immunocompromised patients. Samples were obtained from 37 HIV-infected subjects with lymphocyte levels of CD4+ <200/mm3. The prevalence of IgG antibodies toToxoplasma gondiiwas 64.9 %. Ten patients had clinical symptoms of reactivated toxoplasmosis; eight of these hadToxoplasmaencephalitis. The SAG-1 epitopes were found as circulating antigen in five cases with an immunocapture enzyme immunoassay (EIA). The EIA was improved with an IgG1 monoclonal antibody to SAG-1 and a streptavidinbiotin amplification. The sensitivity, specificity and positive predictive value were 30, 92 and 60 %, respectively. The SAG-1 levels were compared with different biological parameters such as HIV p24 antigen, β2microglobulin, CD4+ cell count and IgG antibodies toToxoplasma gondii.The levels of SAG-1 in these patients were significantly higher than those in the 75 healthy control persons with or without a chronicToxoplasma gondiiinfection. Therefore, SAG-1 may be involved as a marker of reactivated toxoplasmosis in HIV-infected patients.

Patients with HIV and hepatitis C virus (HCV) coinfection have more severe hepatitis-related disease than do patients with HCV infection alone. Highly active antiretroviral therapy (HAART) with protease inhibitor appears to restore pathogen-specific immune responses, especially in patients with persistent undetectable HIV viral load. To evaluate the potent impact of immune restoration induced by HAART on the course of HCVrelated disease, HCV viremia and levels of transaminases were compared between two groups of patients: 10 HIV/HCV-coinfected patients with persistently undetectable HIV viremia (group A) and 12 HIV/HCV-coinfected patients with persistent detectable HIV viremia. No difference was detected in HCV viral load in either group. An increase in transaminases was found only in patients with persistent undetectable HIV viral load, which was correlated with the increase in CD8+ T cells. This may suggest that the restoration of CD8+ T cell cytotoxicity could lead to an enhancement of hepatitis C-related disease in HCV/HIV-coinfected patients receiving HAART.