38 research outputs found
Molecular Tools for Understanding Eco-Epidemiology, Diversity and Pathogenesis of Leishmania Parasites
Solid pseudopapillary tumor of the pancreas: Ecadherin, β-catenin, CD99 new useful markers with characteristic expression (about two case reports)
Solid pseudopapillary neoplasm of the pancreas is a rare tumor that has favorable prognosis. It poses frequently diagnostic challenges. We describe two cases of solid pseudopapillary tumor of the pancreas managed in our department between 2007 and 2011. Two females have mean age of 36.5 years. Clinical presentation include: abdominal pain, bloating and palpable abdominal mass. Tumor is localized in the head of the pancreas in one case and in the tail in the other case. The mean size of the mass was 6 cm (range: 5 to 7 cm). Surgical treatment was performed in two cases. Histological examination confirms the diagnosis of solid pseudopapillary tumor of the pancreas. Immunohistochemical analysis was concordant to the literature data especially concerning CD99 which positivity was in dot, loss of positivity of E-cadherin and nuclear staining of β-catenin. CD10 and α-1-antitrypsin were also positive. One patient was dead 3 days postoperative and neither cancer recurrence nor distant metastases were detected on the follow up of the other. However, solid pseudo-papillary tumor of the pancreas has a distinctive histological appearance; some cases are problematic requiring the use of immunohistochemistry to distinguish it from other pancreatic neoplasm which prognosis is different
The effect of a daytime 60-min nap opportunity on postural control in highly active individuals
Although napping is commonly used as a strategy to improve numerous physical and cognitive performances, the efficacy of this strategy for improving postural balance has not yet been elucidated. Thus, the aim of this study was to conduct a comprehensive examination of the effect of a 60 min nap opportunity (N60) on different components of postural control. Ten highly active individuals (age = 27 ± 3.5 y, height = 1.75 ± 0.52 m, weight = 66.02 ± 8.63 kg) performed, in a randomized order, two afternoon test sessions following no nap (NN) and N60. Postural balance was assessed using the sensory organisation test (SOT), the unilateral stance test (UST), and the limits of Stability Test performed on NeuroCom(®) Smart Balance Master. The subjective rating of sleepiness before and after the nap conditions was also assessed. Compared to NN, N60 improved the composite balance score (p 0.05). Overall, a 60 min post lunch nap opportunity may be viable for improving static balance, although further work, involving larger samples and more complex motor activities, is warranted
The effect of post-lunch napping on mood, reaction time, and antioxidant defense during repeated sprint exercice
To compare the effects of two nap opportunities (20 and 90 min) to countermeasure the transient naturally occurring increased sleepiness and decreased performances during the post-lunch dip (PLD). Fourteen highly trained judokas completed in a counterbalanced and randomized order three test sessions (control (No-nap), 20- (N20) and 90-min (N90) nap opportunities). Test sessions consisted of the running-based anaerobic sprint test (RAST), simple and multiple-choice reaction times (MCRT) and the Epworth sleepiness scale (ESS). From the RAST, the maximum (Pmax), mean (Pmean) and minimum (Pmin) powers were calculated. Blood samples were taken before and after the RAST to measure the effect of pre-exercise napping on energetic and muscle damage biomarkers and antioxidant defense. N20 increased Pmax and Pmean compared to No-nap (p < 0.001, d = 0.59; d = 0.66) and N90 (p < 0.001, d = 0.98; d = 0.72), respectively. Besides, plasma lactate and creatinine increased only when the exercise was performed after N20. Both N20 (p < 0.001, d = 1.18) and N90 (p < 0.01, d = 0.78) enhanced post-exercise superoxide dismutase activity compared to No-nap. However, only N20 enhanced post-exercise glutathione peroxidase activity (p < 0.001, d = 1.01) compared to pre-nap. Further, MCRT performance was higher after N20 compared to No-nap and N90 (p < 0.001, d = 1.15; d = 0.81, respectively). Subjective sleepiness was lower after N20 compared to No-nap (p < 0.05, d = 0.92) and N90 (p < 0.01, d = 0.89). The opportunity to nap for 20 min in the PLD enhanced RAST, MCRT performances, and antioxidant defense, and decreased sleepiness. However, the opportunity of 90 min nap was associated with decreased repeated sprint performances and increased sleepiness, probably because of the sleep inertia
Training during the COVID-19 lockdown : knowledge, beliefs, and practices of 12,526 athletes from 142 countries and six continents
OBJECTIVE Our objective was to explore the training-related knowledge, beliefs, and practices of athletes and the influence of
lockdowns in response to the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome
coronavirus 2 (SARS-CoV-2).
METHODS Athletes (n = 12,526, comprising 13% world class, 21% international, 36% national, 24% state, and 6% recreational)
completed an online survey that was available from 17 May to 5 July 2020 and explored their training behaviors (training
knowledge, beliefs/attitudes, and practices), including specific questions on their training intensity, frequency, and session
duration before and during lockdown (March–June 2020).
RESULTS Overall, 85% of athletes wanted to “maintain training,” and 79% disagreed with the statement that it is “okay to not
train during lockdown,” with a greater prevalence for both in higher-level athletes. In total, 60% of athletes considered “coaching
by correspondence (remote coaching)” to be sufficient (highest amongst world-class athletes). During lockdown, < 40%
were able to maintain sport-specific training (e.g., long endurance [39%], interval training [35%], weightlifting [33%], most (83%) training for “general fitness and health maintenance” during lockdown. Athletes trained alone (80%) and focused
on bodyweight (65%) and cardiovascular (59%) exercise/training during lockdown. Compared with before lockdown, most
athletes reported reduced training frequency (from between five and seven sessions per week to four or fewer), shorter training
sessions (from ≥ 60 to < 60 min), and lower sport-specific intensity (~ 38% reduction), irrespective of athlete classification.
CONCLUSIONS COVID-19-related lockdowns saw marked reductions in athletic training specificity, intensity, frequency, and
duration, with notable within-sample differences (by athlete classification). Higher classification athletes had the strongest
desire to “maintain” training and the greatest opposition to “not training” during lockdowns. These higher classification
athletes retained training specificity to a greater degree than others, probably because of preferential access to limited training
resources. More higher classification athletes considered “coaching by correspondence” as sufficient than did lower
classification athletes. These lockdown-mediated changes in training were not conducive to maintenance or progression of
athletes’ physical capacities and were also likely detrimental to athletes’ mental health. These data can be used by policy
makers, athletes, and their multidisciplinary teams to modulate their practice, with a degree of individualization, in the
current and continued pandemic-related scenario. Furthermore, the data may drive training-related educational resources
for athletes and their multidisciplinary teams. Such upskilling would provide athletes with evidence to inform their training
modifications in response to germane situations (e.g., COVID related, injury, and illness).A specific funding was provided by the National Sports Institute
of Malaysia for this study.The National Sports Institute of Malaysia.https://www.springer.com/journal/40279am2023Sports Medicin
COVID-19 lockdown : a global study investigating athletes’ sport classification and sex on training practices
PURPOSE : To investigate differences in athletes’ knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification. METHODS : Athletes (12,526; 66% male; 142 countries) completed an online survey (May–July 2020) assessing knowledge, beliefs, and practices toward training. Sports were classified as team sports (45%), endurance (20%), power/technical (10%), combat (9%), aquatic (6%), recreational (4%), racquet (3%), precision (2%), parasports (1%), and others (1%). Further analysis by sex was performed. RESULTS : During lockdown, athletes practiced body-weight-based exercises routinely (67% females and 64% males), ranging from 50% (precision) to 78% (parasports). More sport-specific technical skills were performed in combat, parasports, and precision (∼50%) than other sports (∼35%). Most athletes (range: 50% [parasports] to 75% [endurance]) performed cardiorespiratory training (trivial sex differences). Compared to prelockdown, perceived training intensity was reduced by 29% to 41%, depending on sport (largest decline: ∼38% in team sports, unaffected by sex). Some athletes (range: 7%–49%) maintained their training intensity for strength, endurance, speed, plyometric, change-of-direction, and technical training. Athletes who previously trained ≥5 sessions per week reduced their volume (range: 18%–28%) during lockdown. The proportion of athletes (81%) training ≥60 min/session reduced by 31% to 43% during lockdown. Males and females had comparable moderate levels of training knowledge (56% vs 58%) and beliefs/attitudes (54% vs 56%). CONCLUSIONS : Changes in athletes’ training practices were sport-specific, with few or no sex differences. Team-based sports were generally more susceptible to changes than individual sports. Policy makers should provide athletes with specific training arrangements and educational resources to facilitate remote and/or home-based training during lockdown-type events.https://journals.humankinetics.com/view/journals/ijspp/ijspp-overview.xmlhj2023Sports Medicin
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance
INTRODUCTION
Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic.
RATIONALE
We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs).
RESULTS
Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants.
CONCLUSION
Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
Computer Simulation of the Aerodynamic Structure of an Arched Roof Obstacle and Validation with Anterior Results
Abstract The present paper is dedicated to the numerical simulation of the aerodynamic structure of an arched roof obstacle with a height h=63 mm and a length L 2 =118 mm. The governing equations of mass and momentum in conjunction with the standard k-ε turbulence model are solved using the software "Solid Works Flow Simulation". A finite volume discretization is used. The numerical results are validated with anterior results developed in a wind tunnel. The numerical simulations agreed reasonably with the experimental results and the numerical model was validated
Numerical simulation and wind tunnel experiments on wind-induced natural ventilation in isolated building with patio
Development of a cost-effective medium for Photorhabdus temperata bioinsecticide production from wastewater and exploration of performance kinetic
Abstract This study investigates the optimization of the culture conditions for enhancing Photorhabdus temperata biopesticide production using wastewater (WS4) as a raw material. Box-Behnken design (BBD) was used to evaluate the effects of carbon to nitrogen ratio (C/N), sodium chloride concentration and inoculum size on P. temperata biomass production and insecticidal activity. For an enhanced biopesticide production, the optimum operating conditions were as follows: inoculum size = 4%; C/N ratio = 12.5 and [NaCl] = 4 g/L for two responses. 1.95 and 2.75 fold improvements in oral toxicity and biomass production were respectively obtained in the cost-effective medium developed in this study (WS4 I) using the three variables at their optimal values. Under the optimized conditions, WS4 I-grown cells exhibited higher membrane integrity according to flow cytometry analysis since dead cells presented only 9.2% compared to 29.2% in WS4. From batch fermentations carried out in WS4 I and WS4, P. temperata kinetic parameters in terms of biomass production and substrate consumption rates were modeled. The obtained results showed that the maximum specific growth rate in WS4 I was of 0.43 h−1 while that obtained in WS4 was of 0.14 h−1. In addition, the efficiency of P. temperata to metabolize organic carbon was enhanced by optimizing the culture conditions. It reached 72.66% instead of 46.18% in the control fermentation after 10 h of incubation. Under the optimized conditions, P. temperata cells showed the highest specific consumption rate resulting in a toxin synthesis improvement