Crude merozoite antigens from Plasmodium falciparum were used to evaluate the proliferative response of peripheral mononuclear cells (PBMCs) from 114 inhabitants of the village of Dielmo (Senegal, ...West Africa) exposed continuously to malaria transmission. The high or low responses to merozoite antigens obtained in lymphocyte stimulation assays were correlated with the presence or absence of parasites, IFN-gamma production and HLA phenotype. The high responders produced high levels of IFN-gamma, in contrast to the low responders, most of whom did not secrete IFN-gamma (23/27). Among others, the two HLA phenotypes HLA-B51 and HLA-DR1 were significantly associated with a high response (P < 0.05).
Patients suffering from lepromatous leprosy fail to develop an efficient cell-mediated immunity towards Mycobacterium leprae, the causative agent. The mechanism of such a specific T-cell tolerance to ...the bacillus remains a key question in the pathophysiology of leprosy. Macrophages do not show any intrinsic defect in phagocytizing and killing M. leprae or in presenting antigen to helper T-cells. On the other hand, M. leprae-reactive helper T-cells do persist in lepromatous patients, but their activation appears to prevented by active suppressor mechanisms, involving both suppressor T-cells and macrophages. The target of this specific suppression could be the interleukin 2-producing T-cell subset. A better molecular definition of M. leprae antigens, both by monoclonal antibodies and T-cell clones, should open new perspectives for further analysis of the regulation of immune responses to M. leprae.
The European Water Framework Directive clearly indicates that fish is one of the “quality elements” to be considered for the assessment of lentic systems. However, few fish-based indices (FBIs) of ...biotic integrity have been developed for lakes so far.
Hence, the aim of our study was to develop such a tool for French lakes. Fish surveys, lakes natural environmental parameters, catchment-scale anthropogenic pressures, and local pressures were collected for 67 reservoirs and 24 natural lakes throughout France. After assigning fish species into trophic, reproductive, and tolerance guilds, we derived a set of metrics reflecting complementary aspects of community functioning and condition. Other community-level traits such as richness and evenness were added. These metrics were modeled vs. natural environmental variables and pressures. Reference conditions at each site were then assessed using hindcasting modeling. Separate indices were eventually obtained for natural and artificial lakes by combining selected metrics. Fifteen out of 73 candidate fish metrics, covering all three groups of functional traits, displayed a significant response to anthropogenic pressures. After removal of the redundant traits, the final indices for natural lakes and reservoirs included three and six metrics, respectively. Agricultural-related impacts were prominent for reservoirs, whereas for natural lakes urban and local pressures displayed the most significant effects.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A simple preparation procedure to produce conductive graphene coatings from graphenide solution under inert atmosphere is achieved. The obtained graphene films exhibit reasonably low surface ...resistivity of 5 kohms/Square at 60% transmittance at 550 nm that can be largely improved by thermal treatment. XPS, Raman spectroscopy and X-ray diffraction measurements demonstrate that annealing vastly improves the quality of the graphene films. Heat treatment at low temperature (120 °C) demonstrates a 60% resistivity decrease, an impressive and promising improvement for films deposited onto flexible polymer substrate.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Sleep Apnea Syndrome (SAS) prevalence increases with age. In the elderly, symptoms are less specific (falls, cognitive or functional decline, polymedication). Polysomnography, the gold standard ...technique to diagnose SAS, is challenged by sleep laboratories' waiting lists and high associated costs. Nocturnal oximetry is an easy-to-use tool widely available outside the sleep medicine field identifying intermittent hypoxia, the landmark of SAS. It might be an interesting and easy way to screen for SAS in the functionally and cognitively impaired elderly living in long-term care settings.
The primary goal of this study was to assess the accuracy of the variability index of nocturnal pulse oximetry to detect moderate to severe SAS in patients older than 75 hospitalized in stable condition. The secondary goals were to assess the accuracy of the other indices of pulse oximetry (oxygen desaturation index ODI), and to determine the prevalence of moderate to severe SAS in our population.
In-hospital sleep studies with simultaneous respiratory polygraphy and nocturnal pulse oximetry were performed. Comorbidities were assessed by the Cumulative Illness Rating Scale for Geriatrics (CIRS-G) in association with a comprehensive geriatric assessment.
Eighty patients (mean age 85.3 ± 5.3 years) were included. Seventy-two percent of the patients exhibited moderate to severe SAS (95% CI 58.9-82.9), including 59.5% of severe SAS (apnea + hypopnea index >30/hour). SaO2 variability index using a threshold of 0.51, the sensitivity and negative predictive value (NPV) were 100%. With a value above 0.88, positive predictive value and specificity were high (respectively 96.6% and 93.8%). ODI of 3% or higher and 4% or higher were highly specific but less sensitive.
Prevalence of moderate to severe SAS in multimorbid hospitalized elderly patients is high. Automatic analysis of the variability of nocturnal SaO2 is a reliable tool for geriatricians to screen and rule out moderate to severe SAS. Our study suggests an important role of pulse oximetry as the first step in the diagnostic strategy for moderate to severe SAS in this population.
In France, pneumococcal vaccination in adults is recommended for risk groups (chronic conditions/immunosuppression). We conducted a study on invasive pneumococcal disease (IPD) in adults to identify ...factors associated with disease severity and death.
We included IPD cases, excluding meningitis, from 25 acute care hospitals in 6 regions. We defined severe cases as those with shock or severe sepsis or intensive care unit admission/mechanical ventilation. We included deaths occurring within 30 days of hospitalization. Infectious disease specialists collected clinical/microbiological data on cases.
During 2014-2017, 908 nonmeningitis IPD cases were diagnosed; 48% were severe, 84% had comorbidities, 21% died. Ninety percent of cases with comorbidities who previously sought health care were not vaccinated against pneumococcus. Compared with previously healthy cases, the risk of severe IPD increased from 20% (adjusted risk ratio aRR, 1.2; 95% confidence interval CI, 1.0-1.4) in cases with 1-2 chronic diseases to 30% (aRR, 1.3; 95% CI, 1.0-7.0) in those with >2 chronic diseases. Among risk groups, 13-valent pneumococcal conjugate vaccine (PCV13) serotypes and 23-valent pneumococcal polysaccharide vaccine (PPSV23) nonPCV13 serotypes were more likely to induce severe IPD compared with nonvaccine serotypes (aRR, 1.5; 95% CI, 1.3-1.9; aRR, 1.3; 95% CI, 1.0-1.5, respectively).
We observed a cumulative effect of concurrent comorbidities on severe IPD. Vaccine serotypes were more likely to induce severe IPD among risk groups. The missed opportunities for vaccination underscore the need to enhance vaccination in risk groups.
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