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.

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.

Multicentre prospective feasibility study on the repair of hernias and incisional ventral hernias with an innovative Tintrap mesh.

BACKGROUND: The aim of this study is to assess an innovative prosthesis Tintrap Mesh and its inserter in the repair of hernias and incisional ventral hernias. The inserter helps the deployment of the mesh the same way an umbrella would open, which prevents the enlargement of the wound. METHOD: Four centres took part in this study. A questionnaire was completed preoperatively, postoperatively and after 1 month of surgery. Data on pain and complications, patients' satisfaction, as well as the ease of installation and the quality of deployment of the mesh was gathered and assessed. RESULTS: From January 2009 to December 2009, 80 patients were assessed. The prosthesis, ease of installation and the deployment quality were rated "very good" and "good". The average operating room time was 20.86 min (range: 10-50 min). Postoperative pain was rated level 0 and 3 on VAS score in 73 cases (91.25%). After 1 month, no occlusion or relapse were reported on 77 patients; 82.47% of patients had no pain. One seroma required the removal of the mesh. CONCLUSION: The first set of results on 80 cases is encouraging judging by the simplicity of implantation, low postoperative pain and patient's satisfaction.

Theoretical spectrum of noisy optical pulse trains.

The intensity of an ideal optical pulse train is often modeled as an exact periodic repetition of a given pulse-shape function with constant amplitude and width. Therefore, the ideal intensity power spectrum is a pure line power spectrum. However, spontaneous-emission noise due to amplification media, electronic noise due to modulators, or even intentional modulations result in period-to-period fluctuations of the pulse amplitude, width, or arrival time. The power spectrum of this so-called noisy optical pulse train is then composed of a line spectrum added to a band spectrum. This study shows that the optical pulse train intensity is cyclostationary under usual assumptions on the fluctuations. This property allows us to derive the exact optical pulse train power spectrum. A general closed-form expression that takes into account the three noise manifestations (jitter, amplitude, and width modulations) is provided. Particular expressions are given for usual cases of interest such as the jitter and amplitude modulation model, for given fluctuation probability distributions, and pulse-shape functions.

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.

Chaotic mixing in cross-channel micromixers.

In this article we concentrate on a particular micromixer that exploits chaotic trajectories to achieve mixing. The micromixer we consider here is a cross-channel intersection, in which a main stream is perturbed by an oscillatory flow, driven by an external source. Depending on the amplitude and frequency of the oscillatory flow, one obtains wavy and chaotic regimes, reminiscent of a tendril-whorl mapping. The chaotic states, in which material lines are stretched and folded, favour mixing. A spatiotemporal resonance phenomenon, in which the material-line deformation is transient, is shown. An experiment using soft lithography and integrated valves, in which the resonant states are revealed, is described. From a practical viewpoint, the cross-channel micromixer offers a variety of regimes, which can be exploited to mix fluids or separate particles of different sizes. In the context of microsystems, it can be viewed as a 'smart' elementary system.

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.

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.

[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.

Is pleasantness of biscuits and cakes related to their actual or to their perceived sugar and fat contents?

Perceptions of sugar, fat and moisture contents, as well as their influences on pleasantness were investigated in commercial foods. One-hundred-and-two-normal-weight men rated the "pleasantness", "flavour intensity", "moisture", "sweetness" and "fatness" of 39 different biscuits and cakes. Sugar content was accurately perceived up to a maximum content of about 33% weight/weight. The perception of fat content was less accurate and depended on both fat and sugar contents. High sugar contents seemed to decrease perception of fatness. Pleasantness was influenced mainly by sugar content and less by fat content. Pleasantness was better predicted by rated contents than by actual contents; it was even better predicted by the overall flavour intensity. Preferences for high fat stimuli did not appear to be based on conscious perception of their fat content. We conclude that the classical results obtained with simple experimental stimuli remain valid, as a first approximation, for commercial biscuits and cakes, despite their complex sensory characteristics.

[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.

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.

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.

Effect of a fat-reduced dish in a meal on 24-h energy and macronutrient intake.

A covertly fat-reduced and low-calorie dish was provided at lunchtime once a week to normal-weight human subjects. A normal-calorie version of the dish was served for the first 3 weeks, the low-calorie version for the following 4 weeks and the normal-calorie version again for the last 3 weeks. Participants did not compensate for the 840-kJ (201 kcal) fat reduction of their main dish during the lunchtime meal. This lack of compensation persisted after four successive weekly presentations. When the normal-caloric version was offered again, energy intake at lunch immediately recovered. There was 80% adjustment in 24-h energy intake from the first to the last test day on the low-calorie dish, and a return to the baseline level when the normal energy content of the dish was restored. No compensation specific to fat occurred after the consumption of the low-fat dish and so the proportion of energy intake derived from fat decreased from 39.6% in the period on the normal-caloric dish to 36.1% in the 4 weeks on the low-calorie dish. Thus, fat-reduced dishes seem a good means to improve the composition of the diet.

Age-associated changes of rat brain neuronal and astroglial poly(ADP-ribose) polymerase activity.

Nuclear poly(ADP-ribose) polymerase levels as well as the DNA strand break levels of whole-brain neuronal and astroglial cells were investigated. Three- and 30-month-old rats were used. Low-molecular-weight neurofilaments and glutamine synthetase served as neuronal and astroglial markers, respectively. A large increase in the poly(ADP-ribose) polymerase activity was observed in the neurons (threefold) and astrocytes (3.7-fold) derived from 30-month-old rats. Similarly, the amount of poly(ADP-ribose) polymerase, evaluated per milligram of DNA, increased approximately 3.5-fold in neurons and 3.9-fold in astrocytes prepared from 30-month-old rats. Whether the increase in the poly(ADP-ribose) polymerase activity was due to an enhanced rate of DNA strand break was investigated by determining the rate of DNA unwinding. A significant increase in DNA unwinding rate was detected in the neurons (2.7-fold), although a lower increase was observed in the astroglia (1.3-fold) of aged animals.

Cell culture of tumors alters endogenous poly(ADPR)polymerase expression and activity.

Poly(ADP-ribose)polymerase, a chromatin-bound enzyme, actively participates in processes such as cell proliferation, differentiation, and DNA repair and replication. This enzyme is also implicated in cell transformation, and its inhibition has been proposed to potentiate anti-cancer drug activity. Since cells prepared from tumor biopsies and established tumor cell lines are commonly used to evaluate the efficiency of anticancer therapies, we have compared poly(ADP-ribose)polymerase activity in animal tumor cells growing in vivo and in cell culture. Three tumor types were tested: a mastocytoma (P815), a lymphoma (RDM4), and a glioma (C6). Our results show that cell culture alters poly(ADP-ribose)polymerase levels and activity. Endogenous poly(ADP-ribose) activity was several fold higher in exponentially growing cells than in cells freshly recovered from solid or ascitic tumors. Moreover, polymerase activity increased with culture time, reaching a maximum when cells became confluent. Measurements of poly(ADP-ribose)polymerase gene expression and protein amount indicate that lower enzyme activity in tumors grown in vivo are sustained by decreases in poly(ADP-ribose)polymerase mRNA and protein amount. In contrast, the increase in endogenous poly(ADP-ribose)polymerase activity observed in cultured cells was due to enzyme activation and not to de novo protein synthesis. Such differences must be considered when assessing the applicability of cell-culture results to in vivo situations.