Progressive anticipation in behavior and brain activation of rats exposed to scheduled daily palatable food.

Scheduled and restricted access to a palatable snack, i.e. chocolate, elicits a brief and strong anticipatory activation and entrains brain areas related with reward and motivation. This behavioral and neuronal activation persists for more than 7days when this protocol is interrupted, suggesting the participation of a time-keeping system. The process that initiates this anticipation may provide a further understanding of the time-keeping system underlying palatable food entrainment. The aim of this study was to analyze how this entraining protocol starts and to dissect neuronal structures that initiate a chocolate-entrained activation. We assessed the development of anticipation of 5g of chocolate during the first 8days of the entrainment protocol. General activity of control and chocolate-entrained rats was continuously monitored with movement sensors. Moreover, motivation to obtain the chocolate was assessed by measuring approaches and interaction responses toward a wire-mesh box containing chocolate. Neuronal activation was determined with c-Fos in reward-related brain areas. We report a progressive increase in the interaction with a box to obtain chocolate parallel to a progressive neuronal activation. A significant anticipatory activation was observed in the prefrontal cortex on day 3 of entrainment and in the nucleus accumbens on day 5, while the arcuate nucleus and pyriform cortex reached significant activation on day 8. The gradual response observed with this protocol indicates that anticipation of a rewarding food requires repetitive and predictable experiences in order to acquire a temporal estimation. We also confirm that anticipation of palatable food involves diverse brain regions.

Growth and final product formation by Bifidobacterium infantis in aerated fermentations.

Fermentation conditions were developed to allow Bifidobacterium infantis to grow in the presence of air. Batch fermentations in TPYG medium, starting from anoxic conditions followed by the application of low airflow rates [0.02-0.1 air volume, per liquid media volume, per minute (vvm)], were analyzed for growth, oxygen uptake, and product formation by the bacterium. Under all aerated fermentations, B. infantis showed high aerotolerance, with a maximum oxygen-specific consumption rate of 0.34 mmol oxygen per gram dry cell weight per hour in the presence of 0.06 vvm. Similar growth yields were obtained under oxic and anoxic conditions (0.11-0.13 and 0.11 g dry cell weight per mmol glucose, respectively). Oxygen also influenced metabolite formation since lactate production and its molar relation to acetate increased and formate decreased with aeration rate. Under anoxic conditions, a maximum concentration of 8.1 mM lactate and an acetate/lactate ratio of 3.5:1 were obtained, while under oxic conditions the lactate concentration increased more than two-fold and the acetate/lactate molar ratio decreased to 1.5:1. The possibility of balancing acetate/lactate molar ratios for organoleptic purposes as well as for obtaining good growth under microaerated conditions was demonstrated.

The underestimated advantages of iliofemoral endarterectomy.

Iliofemoral endarterectomy was invented 50 years ago, but it is seldom practiced today for two reasons. The first is that it is technically challenging and the second is that outcome in early series was poor. Our preliminary experience having been more encouraging, we have continued to perform iliofemoral endarterectomy for the past 20 years. The purpose of this retrospective study was to evaluate our results and compare them with results of alternative techniques described in recent literature. We have performed a total of 176 iliofemoral endarterectomies in patients with normal or nearly normal aortas. The procedure involved the entire network including the common iliac artery, external iliac artery, and common femoral artery in 108 cases (group I), the common iliac artery with or without the external iliac artery in 40 cases (group II), and the external iliac arteries and the common femoral artery with or without the deep femoral artery in 28 cases (group III). From our results we conclude that iliofemoral endarterectomy should be used as a first-choice modality in patients with normal or nearly normal aortas who present with iliac lesions that are either too long for balloon angioplasty or impossible to recanalize. It eliminates the risk of graft infection and false aneurysm. Restenosis can be treated by balloon angioplasty. It also saves the cost of a prosthesis.

Are femoro-infrapopliteal bypasses worthwhile for limb salvage?

OBJECTIVE: This study was performed in order to determine if: 1-- femoral bypasses ending below the popliteal artery are justified in aged patients or in patients with poor general conditions, 2-- if the use of prosthetic material is justified when no vein is available, 3-- if reintervention is beneficial in case of bypass occlusion. EXPERIMENTAL DESIGN: Retrospective study of 162 infrapopliteal bypasses followed during 1 to 12 years (mean: 1.5). SETTING: Vascular Surgery Department of the University Hospital Henri Mondor based in a suburb of Paris, France. PATIENTS: All patients who underwent a femoral bypass ending below the popliteal artery for limb salvage from January 1984 to December 1995. INTERVENTION: These bypasses were performed with a vein in 131 cases and with a PTFE graft (with or without distal cuff) in 31 cases. MEASURES: All patients were followed with clinical evaluation and duplex scan. Primary and secondary patency, limb salvage and patient survival were studied. The survival rates at 1 and 5 years were 87+/-3.8% and 66+/-9.6% respectively. Preoperative mortality was 7.4%. Renal insufficiency requiring dialysis, not age over 80, was associated with high perioperative mortality. RESULTS: The primary patency rates of the total series at 1 and 5 years were 55 and 35% respectively for the total series. For venous bypasses, it was 58 and 37% while for prosthetic bypasses, it was 49 and 15%. The secondary patency rates at 1 and 5 years were 67 and 46% for the total series. For venous bypasses, it was 70 and 49% and for prosthetic bypasses, it was 53 and 21%. Limb salvage rates at 1 and 5 years were 65 and 61% for the total series, 73 and 65% for venous bypasses and 48 and 41% for prosthetic bypasses. CONCLUSION: 1-- Femorotibial or peroneal bypasses are worthwhile for limb salvage even in aged patients but renal insufficiency requiring dialysis may justify primary amputation. 2-- If no vein can be used, prosthetic or composite bypasses should be performed because they are associated with a 41% limb salvage rate at 5 years. 3-- If thrombosis occurs, the increase of patency after re-operation is 12% in case of venous bypass and 6% in case of prosthetic bypass.