Metabolisation of thiamethoxam (a neonicotinoid pesticide) and interaction with the Chronic bee paralysis virus in honeybees.

Pathogens and pesticides are likely to co-occur in honeybee hives, but much remains to be investigated regarding their potential interactions. Here, we first investigated the metabolisation kinetics of thiamethoxam in chronically fed honeybees. We show that thiamethoxam, at a dose of 0.25ng/bee/day, is quickly and effectively metabolised into clothianidin, throughout a 20day exposure period. Using a similar chronic exposure to pesticide, we then studied, in a separate experiment, the impact of thiamethoxam and Chronic bee paralysis virus (CBPV) co-exposure in honeybees. The honeybees were exposed to the virus by contact, mimicking the natural transmission route in the hive. We demonstrate that a high dose of thiamethoxam (5.0ng/bee/day) can cause a synergistic increase in mortality in co-exposed honeybees after 8 to 10days of exposure, with no increase in viral loads. At a lower dose (2.5ng/bee/day), there was no synergistic increase of mortality, but viral loads were significantly higher in naturally dead honeybees, compared with sacrificed honeybees exposed to the same conditions. These results show that the interactions between pathogens and pesticides in honeybees can be complex: increasing pesticide doses may not necessarily be linked to a rise in viral loads, suggesting that honeybee tolerance to the viral infection might change with pesticide exposure.

Effectiveness of mRNA BNT162b2 COVID-19 vaccine against SARS-CoV-2 Delta variant among elderly residents from a long-term care facility, South of France, May 2021.

OBJECTIVE: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Delta variant was classified as a variant of concern in May 2021 due to its increased transmissibility. It became dominant in Europe during the summer, raising concerns on the effectiveness of vaccines. We assessed the vaccine effectiveness (VE) of mRNA BNT162b2 (BioNTech-Pfizer) against SARS-CoV-2 Delta variant during an outbreak affecting long-term care facility (LTCF) residents in southern France, May 2021. MATERIALS AND METHODS: We conducted a retrospective cohort study among LTCF residents. We described sex, age, dependency level, reverse transcription PCR and sequencing results, clinical evolution, vaccination status. We compared attack rates of SARS-CoV-2 infection, symptomatic coronavirus disease 2019 (COVID-19), and severe COVID-19 (respiratory support, hospitalization, and/or death) by vaccination status (two doses administered vs. none) to estimate VE (1 - Relative Risk [RR]) with 95% confidence intervals (CI). VE was adjusted by age (Poisson regression). RESULTS: Among 72 LTCF residents, 75.0% (n=54) were women, mean age was 88.7 (SD 8.1) years, 69% (n=49/71) were severely dependent. SARS-CoV-2 infections were identified in 39 residents (54.2%), 11 with symptomatic, and eight with severe COVID-19. All sequenced samples (n=19, 48.7%) had the same Delta variant genomic sequence. Age-adjusted BNT162b2 VE against SARS-CoV-2 Delta variant infection was 11.2% (95% CI: 0.0-61.1%), it was 88.4% (95% CI: 59.9-96.7%) against symptomatic, and 93.5% (95% CI: 67.2-98.7%) against severe COVID-19. CONCLUSIONS: We found a high BNT162b2 VE against symptomatic and severe COVID-19 caused by SARS-CoV-2 Delta variant among LTCF elderly residents, but not against Delta variant infection. This supports vaccination rollout and the implementation of control measures for close contacts among vaccinated LTCF elderly residents.

Power spectra for laser-extinction measurements.

Recent laser technology provides accurate measures of the dynamics of fluids and embedded particles. For instance, the laser-extinction measurements (LEM) uses a laser beam passing across the fluid and measures the residual laser light intensity at the fluid output. The particle concentration is estimated from this measurement. However, the particle flow is submitted to random time-varying fluctuations. This study thus proposes to model the received intensity by an appropriate random process. This paper first models the particle flow by a queueing process. Second, the measured intensity power spectrum is derived according to this random model. Finally, the simple case of a constant particle velocity is developped. The proposed model allows to generalize results previously obtained in the litterature with simplified models. Moreover, the particle celerity estimate is provided.

Poly(ADPR)polymerase expression and activity during proliferation and differentiation of rat astrocyte and neuronal cultures.

Poly(ADPR)polymerase (poly(ADPR)P) mRNA and enzymatic activity levels were investigated in primary cultures of rat astrocytes and neurons in the absence or presence of basic fibroblast growth factor (bFGF) and nerve growth factor (NGF), respectively. In cultured rat astrocytes, a biphasic increase in poly(ADPR)P mRNA, associated with enhanced nuclear poly(ADPR)P enzymatic activity, were observed. The first rise in poly(ADPR)P mRNA and enzymatic activity is at the beginning of cell proliferation and the second with the occurrence of cell differentiation. In the presence of bFGF (5 ng/ml) the mRNA peaks and the differentiation-associated poly(ADPR)P enzymatic activity undergoes a 2-fold increase. In neuronal cultures an initial high level of poly(ADPR)P mRNA is followed by a decrease while differentiation is progressively achieved. A limited increase of poly(ADPR)P activity is observed during this phase. In the presence of NGF (50 ng/ml), similar poly(ADPR)P mRNA expression and enzymatic activity patterns are observed. The results suggest that poly(ADPR)P is involved at the onset of nerve-cell proliferation and differentiation.

Cephalic phase responses to sweet taste.

The sweet taste of nonnutritive sweeteners has been reported to increase hunger and food intake through the mechanism of cephalic-phase insulin release (CPIR). We investigated the effect of oral sensation of sweetness on CPIR and other indexes associated with glucose metabolism using nutritive and nonnutritive sweetened tablets as stimuli. At lunchtime, 12 normal-weight men sucked for 5 min a sucrose, an aspartame-polydextrose, or an unsweetened polydextrose tablet (3 g) with no added flavor. The three stimuli were administered in a counterbalanced order, each on a separate day at 1-wk intervals. Blood was drawn continuously for 45 min before and 25 min after the beginning of sucking and samples were collected at 1-min intervals. Spontaneous oscillations in glucose, insulin, and glucagon concentrations were assessed as were increments (slopes) of fatty acid concentrations during the baseline period. The nature of the baseline (oscillations: glucose, insulin, and glucagon; and slopes: fatty acids) was taken into account in the analyses of postexposure events. No CPIR and no significant effect on plasma glucagon or fatty acid concentrations were observed after the three stimuli. However, there was a significant decrease in plasma glucose and insulin after all three stimuli. Only the consumption of the sucrose tablet was followed by a postabsorptive increase in plasma glucose and insulin concentrations starting 17 and 19 min, respectively, after the beginning of sucking. In conclusion, this study suggested that oral stimulation provided by sweet nonflavored tablets is not sufficient for inducing CPIR.

An endocrine and metabolic definition of the intermeal interval in humans: evidence for a role of leptin on the prandial pattern through fatty acid disposal.

BACKGROUND: It has been proposed that leptin provides a hormonal link between adipose stores and food intake. OBJECTIVE: This study investigated the role of leptin in the prandial pattern. DESIGN: In experiment 1, a spontaneous prandial pattern was recreated in 6 young, normal-weight men who were deprived of time cues and had blood withdrawn continuously at a frequency of one tube every 5 min. Meals were consumed ad libitum and dinner was requested voluntarily. Data from a second experiment, conducted in 8 subjects, were used to confirm the changes in leptin during the intermeal interval (IMI). RESULTS: Plasma leptin gradually rose to a peak (62 +/- 18% of the lunch concentration) during the IMI and declined before the dinner request (-21 +/- 4% of the peak concentration). This preprandial decline was confirmed in experiment 2 (-15 +/- 9%). The leptin concentration at lunch and fat-free mass were the only significant predictors of the IMI (both: r(2) = 0.91, P = 0.03). With fat intake at lunch, the leptin concentration at lunch was a positive predictor of the area under the curve of plasma fatty acids during the IMI (r(2) = 0.95, P = 0.01). Moreover, the leptin concentration at lunch was negatively correlated with energy intake in the first course of this meal (r = -0.95, P < 0.005). A similar result was found at dinner (r = -0.85, P < 0.05). Last, the change in leptin was predicted accurately by changes in glucose, triacylglycerol, and fatty acids (r(2) = 0.87, P < 10(-5)). CONCLUSION: Plasma leptin concentrations increase during a spontaneous IMI and decline before the onset of a meal. The results argue for a role of leptin in the prandial pattern through fatty acid peripheral disposal.

A method for long-term and accurate measurement and recording of the blood glucose level in man.

We describe a technique of continuous and long-term withdrawal of venous blood which permits a continuous measurement and recording of the blood glucose level. The preparation and setting up of a special double lumen catheter are detailed. This technique provides very accurate blood glucose time course determination and requires the withdrawal of small amounts of blood.

Effects of acute treadmill exercise and delayed access to food on food selection in rats.

Total energy intake and macronutrient self-selection were examined in rats following forced exercise (2 h treadmill, 15 m/min) or after a similar period of food deprivation without exercise. Acute exercise was realized at the end of the daytime. Return to the home cage for food access after exercise or after the same period of fasting was delayed for 0, 30, and 90 min. It has been shown that rats decreased body weight after all exercise situations. Food intake after deprivation was decreased in the first 3 h but was not modified over 24 h. The 24-h energy intake after exercise was identically reduced in the three situations. Carbohydrate and protein intakes were significantly reduced just after exercise. Protein decrease persisted all through the night and, to a lesser extent, during the following nycthemere. Fat decrease appeared later and was significant in the last part of the night. Increasing the delay to food access after exercise did not modify the total energy intake, but it significantly reduced carbohydrate intake. Those results show that exercise has a longer influence on food intake and, specifically, on macronutrient selection, than just food deprivation. Various hypotheses regarding central (cerebral neurotransmitters) and peripheral factors could be evoked in order to explain these modifications in the self-selected diet after an acute exercise.

Monosodium glutamate as a palatability enhancer in the European diet.

Can monosodium glutamate (MSG) augment palatability in foods of the occidental diet? Its effects on the palatability of two experimental foods were investigated in 36 healthy young men and women. MSG improved palatability ratings, with an optimum at 0.6%. Weekly tests of free intake showed that subjects fed the experimental foods with 0.6% MSG added ate progressively more and faster, indicating increasing palatability with repeated exposure. The effects of MSG on familiar foods were investigated in a group of 65 institutionalized elderly persons. Spontaneous intake was measured at lunch time on 12 test days. Target foods (soup and vegetable) were served either without or with 0.6% MSG added. MSG facilitated intake of some but not all target foods, and was associated with positive (increased calcium and magnesium intake) or adverse (increased fat intake) nutritional effects. It is concluded that MSG can act as a palatability enhancer in the context of the French diet. It can facilitate long-term intake in both young and elderly persons but it should be utilized cautiously so as to improve nutrition.

Laparoscopic repair of incisional hernia: a retrospective study of 159 patients.

BACKGROUND: In this long-term retrospective study, a laparoscopic technique was used for incisional hernia repair. METHODS: Over a 6-year period, we performed laparoscopic repairs with prosthetic mesh in 159 patients suffering from incisional hernia. Morbidity factors were noted and operative data were collected. In addition, early and long-term complications and recurrences were analyzed. RESULTS: There were no deaths as a result of the procedure. In 21 patients (13.8%), the operation was converted to an open procedure. Small bowel perforation occurred in three patients (1.9%). Mean hospital stay was 3.5 days. Early complications occurred in 61 patients (44%). The mean follow-up time was 49 months. There were no infections of the prosthetic mesh. Residual abdominal pain was reported in 31 patients (26%). Bowel obstructions requiring resection were found in two patients (1%), and hernia recurrence was observed in 19 patients (15.7%). CONCLUSIONS: Laparoscopic herniorraphy is a promising technique with all the advantages of minimal-invasive surgery. Nevertheless, close attention needs to be paid to the choice of the hernia and mesh size and to the fixing of the mesh.

3D reconstruction in electrical impedance imaging using a direct sensitivity matrix approach.

This paper represents a reconstruction algorithm using a direct sensitivity matrix (DSM) approach for fast 3D image reconstruction in electrical impedance imaging. The boundary element method (BEM) is used in the construction of this matrix. The first images of a conductivity perturbation inside a sphere are reconstructed, using theoretical data.

[Alteration of cardiovascular vagosympathetic control evaluated by spectral analysis of variations of heart rate and blood pressure in obesity]. / Altération du contrôle vagosympathique cardiovasculaire évalué par l'analyse spectrale des variations de fréquence cardiaque et de pression artérielle chez les obèses.

Several studies suggest alterations of parasympathetic and sympathetic control in obesity. We have already shown that more than 40% of non diabetic obese subjects have alterations of parasympathetic control of heart rate (HR) variations. The present study aimed to investigate parasympathetic and sympathetic cardiovascular control by using spectral analysis. Sixty-two non diabetic obese subjects were compared to 38 sex-matched healthy controls. Spectral analysis was performed by Anapres system and identified two particular peaks: the one of high frequency (0.20-0.25 Hz) for heart rate variations during controlled breathing which depends on parasympathetic activity, the other of low frequency (around 0.10 Hz) for systolic BP variations in the standing position which mainly depend on sympathetic activity. In control subjects the amplitude of the high frequency peak (r = -0.556, p < 0.0001) but not the amplitude of the low frequency peak correlated negatively with age. In the obese subjects both the high and low frequency peaks correlated negatively with age (r = -0.249; p = 0.05 and r = -0.289, p = 0.036 respectively) and did not correlate with body mass index. The high frequency peak was significantly lower than in controls (4.80 +/- 3.37 (SD) vs 8.38 +/- 4.14; p < 0.0001). In the 25 obese subjects over 40 years the low frequency peak was also significantly lower than in controls (10.00 +/- 3.10 vs 11.95 +/- 4.25; p < 0.05). This study suggests that 1) age must be taken into account when interpreting the cardiovascular parameters under vagosympathetic control; 2) in non diabetic obese subjects vagal activity is decreased and in those over 40 years sympathetic activity is also decreased.

[Calibrated side-to-side portacaval anastomosis in the treatment of bleeding from ruptured esophageal varices. Results in 38 cirrhotic patients]. / L'anastomose porto-cave latéro-latérale calibrée dans le traitement des hémorragies par rupture de varices oesophagiennes. Résultats à propos de 38 patients cirrhotiques.

We report the clinical results of 38 calibrated side-to-side portocaval shunts performed in patients with hemorrhagic liver cirrhosis (alcoholic in 90 percent of cases). The operative mortality (at 2 months) was 10.5 percent. The rate of recurrent bleeding was 2.6 percent; hepatic encephalopathy was encountered in 16 percent (acute encephalopathy: 6.5 percent; chronic encephalopathy: 9.6 percent; this rate decreased to 3.2 percent after anastomotic narrowing). Hepatopedal portal blood flow was maintained in 74.3 percent of cases in the early postoperative period (83.3 percent since the portacaval pressure gradient was maintained at 2/3 of the initial gradient) and disappeared with time in 75 percent of cases. The survival rates at 1 and 4 years were 79.4 percent and 60 percent, respectively, for all patients (94.4 and 83.3 percent for Child A patients) with a normal social activity in 90 percent of cases. Twelve patients developed hepatocellular carcinoma. These clinical results are similar to those observed after selective shunts and suggest that the side-to-side calibrated portacaval shunt is an excellent procedure for the treatment of bleeding esophageal varices in case of failure or contraindication to endoscopic sclerotherapy or in patients with chronic ascites and good liver function.

[Marion's calibrated latero-lateral portacaval anastomosis: a truncular shunt maintaining hepatopetal portal blood flow?]. / L'anastomose porto-cave latéro-latérale calibrée de Marion: une dérivation tronculaire maintenant un flux portal hépatopète?

The authors report the hemodynamic study of 22 cases of calibrated side-to-side portacaval shunts performed in patients with liver cirrhosis. In all patients, hepatopetal portal blood flow was present before the operation. According to the data obtained by scintiangiography and angiography, hepatopetal portal flow was maintained in 70 p. 100 of the patients immediately after the operation. After one year there was a discrepancy between the results of scintiangiography and those of conventional angiography: while portal flow seemed to be hepatopetal on the scintigraphy in 11 of controlled patients, it decreased or disappeared on the angiography in 6 other controlled patients. These results are comparable to those of selective shunts and suggest that the calibrated side-to-side portacaval shunt is a valuable procedure in maintaining hepatopetal portal flow. A controlled trial would be useful to assess the place of this operation in the treatment of portal hypertension due to cirrhosis.

[Comparative study of two methods permitting the detection of macroamylases. Application to the evaluation of macroamylasemia in a hospitalized population]. / Etude comparative de deux méthodes permettant la détection de macroamylases. Application à l'évaluation d'une macroamylasémie dans une population hospitalière.

It is of great importance to be able to distinguish hyperamylasemia linked to a pathological condition of the pancreas from one due to the presence of the macroamylase in the serum of the patient. We have evaluated both gel filtration chromatography and precipitation by PEG-6000 for the detection of serum macroamylase. Our study has enabled us to define a simple detection protocol, suitable for routine laboratory use. In this protocol, macroamylasemia is detected initially by precipitation with PEG-6000; if less than 60% of amylase activity is precipitated, there is no macroamylasemia. If more than 60% of amylase activity can be precipitated by PEG-6000, macroamylasemia is confirmed by gel filtration chromatography. The incidence of macroamylasemia in hospitalized patients was studied; it was 1.3% in cases where amylasemia was normal, and 4.5% in hyperamylasemic patients.

[Mechanical value of prostheses and fixation with staples in repair of abdominal eventrations]. / Etude expérimentale: valeur mécanique des prothèses et fixation par agrafes, dans la cure des éventrations abdominales.

From an experimental study on fresh corpses, using a system which allows reproductible measures, we evaluated the physical strain to which prosthetic meshes are subjected during the initial phase of repair of abdominal eventrations treated by mesh. We also studied the various systems of staple fixation. The adhesivity or resistance-to-tear of the mesh is minimally dependent on the texture of the plaque; additionall, we also demonstrated the role of the size of the mesh. Stapling may compensate for the lack in size and increase the resistance-to-slip with larger values for radial stapling as compared to tangential stapling. Other fields of applications are possible. The use of glue or absorbable staples is considered.

[Proposal for a polyvalent Simplified Acute Physiology Score of severity in biliary tract surgery]. / Proposition d'un score de gravité polyvalent "SAPS" en chirurgie biliaire.

The SAPS score proposed by Le Gall, was used in 128 patients undergoing biliary surgery between January 1987 and April 1988. The score is based on the laboratory data for the first day. The cumulative post-operative complication rate was established during hospital stay and at one month after discharge. There is a highly significant correlation between the SAPS score, the morbidity and the mean hospital stay. From this study it seems valuable to use this score in surgery reports.

[Trendelenburg's operation using an sternostomy approach for pulmonary embolectomy]. / Opération de Trendelenburg par sternotomie pour embolectomie pulmonaire.

Five cases of extremely serious pulmonary embolism treated by embolectomy without extracorporeal circulation have prompted to recall the Trendelenburg's operation through sternotomy. Rapid, simple and requiring little equipment, this technique is perfectly suited to emergency surgery. Its use should save the lives of several patients who would be condemned to death without surgical operation.

[Azygo-portal disconnection by the abdominal route]. / Déconnexion azygo-portale par voie abdominale.

Azygo-portal disconnection by the abdominal route consists of devascularization of the lower oesophagus, cardiac orifice and greater gastric tuberosity by ligation of the varices and section of the oesophagus, combined in every case with truncular vagotomy and gastric bypass. In emergencies the abdominal approach enables the bleeding points to be accurately localized. In the treatment of haemorrhages due to portal hypertension, this technique offers an alternative to porto-caval bypasses when these cannot be performed (thrombosis or portal cavernoma) or when the risk of encephalitis is too high. However, contrary to liver transplantation, it is a palliative technique for cirrhotic patients.

[Value of the peroperative association of echography, extemporaneous cytology and immediately available insulin blood levels of the portal vein. Apropos of 2 cases of insulinoma]. / Intérêt de l'association per-opératoire de l'échographie, de la cytologie extemporanée et des dosages d'insulinémie portale avec résultats immédiats. A propos de deux cas d'insulinome.

The authors report two cases of insulinoma managed by per-operative ultrasound and cytology, together with immediate portal vein insulin levels. They stress the value of these per-operative exploratory techniques which reduce the number of pre-operative invasive examinations while ensuring a greater efficacy in the localization and treatment of these tumors.