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1.
Diagnostics (Basel) ; 14(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611637

RESUMO

The early diagnosis of malaria is crucial to controlling morbidity and mortality. The World Health Organization (WHO) recommends diagnosing malaria either using light microscopy or a malaria rapid diagnostic test (RDT). Most RDTs use antibodies to detect two P. falciparum histidine-rich proteins named PfHRP2 and PfHRP3. However, false-negative results are known to occur due to the poor performance of RDTs depending on the species and the deletion of the Pfhrp2 and Pfhrp3 genes. This study evaluated new malaria RDTs for the detection of the human Plasmodium species. The Acro Malaria P.f./P.v./Pan Rapid Test Cassette allows the qualitative detection of parasite antigens, such as PfHRP2 specific to Plasmodium falciparum, PvLDH specific to Plasmodium vivax, and/or panLDH Plasmodium genus lactate dehydrogenase, in the blood of infected individuals. This RDT was assessed against 229 samples collected from imported malaria cases, mainly from Africa. The samples were previously diagnosed using light microscopy and RDT (SD Malaria Ag P.f./Pan, SD Bioline Alere Abbott), then confirmed using real time PCR. The two RDTs were evaluated using a comparison with real time PCR as the reference method, and their performances were compared with each other. Compared to SD RDT, the Acro RDT showed a better sensitivity to P. falciparum (96.8% vs. 89.8%), P. vivax (78.6% vs. 64.3%), P. ovale (73.7% vs. 5.3%), and P. malariae (20.0% vs. 0%). The respective specificities of the Acro RDT and SD RDT are 90.7% vs. 95.3% to P. falciparum, 100% to P. vivax, and 100% vs. 100% to Plasmodium genus. Therefore, Acro RDT showed better performance in the identification of P. ovale and low parasitaemia of P. falciparum. In addition, Acro RDT has the advantage of detecting PvLDH-specific antigens. The Acro Malaria RDT presents the benefits of detecting a P. falciparum antigen (PfHRP2) and a P. vivax antigen (PvLDH) with high sensitivity (96.8% and 73.7%, respectively) and specificity (90.7% and 100%, respectively). Acro Malaria P.f./P.v./Pan rapid diagnostic tests could be effectively used in endemic areas, especially when microscopic examination cannot be performed.

3.
Vox Sang ; 119(2): 134-143, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37997609

RESUMO

BACKGROUND AND OBJECTIVES: Most research studies on the effects of repeated plasma donation are observational with different study limitations, resulting in high uncertainty on the link between repeated plasma donation and health consequences. Here, we prospectively investigated the safety of intensive or less intensive plasma donation protocols. MATERIALS AND METHODS: Sixty-three male subjects participated in this randomized controlled trial and were divided into low-frequency (LF, once/month, n = 16), high-frequency (HF, three times/month, n = 16), very high-frequency (VHF, two times/week, n = 16) and a placebo (P, once/month, n = 15) groups. Biochemical, haematological, clinical, physiological and exercise-related data were collected before (D0), after 1½ months (D42) and after 3 months (D84) of donation. RESULTS: In VHF, red blood cells, haemoglobin and haematocrit levels decreased while reticulocyte levels increased from D0 to D84. In both HF and VHF, plasma ferritin levels were lower at D42 and D84 compared to D0. In VHF, plasma levels of albumin, immunoglobulin G (IgG), immunoglobulin A (IgA) and immunoglobulin M (IgM) dropped from D0 to D42 and remained lower at D84 than at D0. In HF, plasma IgG, IgA and IgM were lower at D42, and IgG and IgM were lower at D84, compared to D0. Few adverse events were reported in HF and VHF. Repeated plasma donation had no effect on blood pressure, body composition or exercise performance. CONCLUSION: VHF plasmapheresis may result in a large reduction in ferritin and IgG levels. HF and VHF plasmapheresis may result in little to no difference in other biochemical, haematological, clinical, physiological and exercise-related parameters.


Assuntos
Imunoglobulina G , Plasmaferese , Humanos , Masculino , Plasmaferese/efeitos adversos , Imunoglobulina A , Imunoglobulina M , Ferritinas , Nível de Saúde
4.
Case Rep Oncol ; 16(1): 1395-1401, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028579

RESUMO

Introduction: Cardiac metastasis (CM) is a rare lung cancer location. It often remains clinically silent but may cause life-threatening complications. Better survival rates thanks to the immunotherapy revolution and the improving performance of imaging lead to an increasing number of CM diagnosis. Case Presentation: We report a case of a 54-year-old woman who was diagnosed with a stage IIIa non-small cell lung cancer. She developed a right ventricular CM without symptoms during treatment by immunotherapy after concurrent chemoradiotherapy. Cardiac magnetic resonance imaging confirmed the presence of an endocavitary lesion in the right ventricle apex. Complete surgical resection through a right ventriculotomy was performed. Conclusion: The diagnosis of similar cases has become more frequent due to immunotherapy and more advanced imaging technology. Our case report also highlights the fact that CM surgery has to be considered as a successful therapeutic option in those oligo-progression situations. Guidelines on the management and treatment of lung cancer CM are needed as well as larger studies to evaluate the survival benefit from surgical treatment.

6.
Mol Ecol Resour ; 23(2): 410-423, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36161270

RESUMO

Emerging and endemic mosquito-borne viruses can be difficult to detect and monitor because they often cause asymptomatic infections in human or vertebrate animals or cause nonspecific febrile illness with a short recovery waiting period. Some of these pathogens circulate into complex cryptic cycles involving several animal species as reservoir or amplifying hosts. Detection of cases in vertebrate hosts can be complemented by entomological surveillance, but this method is not adapted to low infection rates in mosquito populations that typically occur in low or nonendemic areas. We identified West Nile virus circulation in Camargue, a wetland area in South of France, using a cost-effective xenomonitoring method based on the molecular detection of virus in excreta from trapped mosquitoes. We also succeeded at identifying the mosquito species community on several sampling sites, together with the vertebrate hosts on which they fed prior to being captured using amplicon-based metabarcoding on mosquito excreta without processing any mosquitoes. Mosquito excreta-based virus surveillance can complement standard surveillance methods because it is cost-effective and does not require personnel with a strong background in entomology. This strategy can also be used to noninvasively explore the ecological network underlying arbovirus circulation.


Assuntos
Arbovírus , Culicidae , Flavivirus , Vírus do Nilo Ocidental , Animais , Humanos , Arbovírus/genética , Biodiversidade
7.
Diagnostics (Basel) ; 12(11)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36359590

RESUMO

Malaria is the most common human parasitic disease in the world with the highest morbidity and mortality. Due to the severity of malaria caused by Plasmodium falciparum and the urgency of therapeutic management, quick and reliable diagnosis is required for early detection. Blood smear microscopy remains the gold standard for malaria diagnosis. Molecular diagnosis techniques are the most sensitive and specific in cases of low parasitaemia and in the detection of mixed infections. The purpose of this study was to evaluate a new commercial test involving the molecular diagnostic technique to detect the five human Plasmodium species. The Vitassay qPCR Malaria 5 test is based on the multiplex real-time PCR of a conserved target region of the 18S rRNA gene for the five human Plasmodium species. A total of 190 samples collected from imported cases of malaria were diagnosed using this test and compared against a homemade reference real-time PCR. The sensitivities of the Vitassay qPCR Malaria 5 test for all Plasmodium species ranged from 93.8% to 100% and specificity ranged from 97.7% to 100%. Based on these criteria, this test is recommended for the diagnosis of the human Plasmodium species.

8.
Diagnostics (Basel) ; 12(9)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36140641

RESUMO

Malaria is one of the most common tropical diseases encountered by members of the French military who are deployed in operations under constrained conditions in malaria-endemic areas. Blood smear microscopy-the gold standard for malaria diagnosis-is often not available in such settings, where the detection of malaria relies on rapid diagnostic tests (RDTs). Ten RDTs (from Biosynex, Carestart, Humasis, SD Bioline, and CTK Biotech), based on the detection of the Plasmodium falciparum histidine-rich protein 2 (HRP2) or lactate dehydrogenase (pLDH, PfLDH, or PvLDH), were assessed against 159 samples collected from imported malaria cases, including 79 P. falciparum, 37 P. vivax, 22 P. ovale, and 21 P. malariae parasites. Samples had been previously characterised using microscopy and real-time PCR. The overall sensitivities for the Plasmodium test ranged from 69.8% (111/159) to 95% (151/159). There was no significant difference for the specific detection of P. falciparum (96.2% to 98.7%, p = 0.845). No significant difference was found between sensitivities to P. vivax by pan LDH or pvLDH (81.1% (30/37) to 94.6% (35/37) (p = 0.845)). Some of the RDTs missed most of P. ovale and P. malariae, with sensitivities for all RDTs ranging respectively from 4.5% (1/22) to 81.8% (18/22) and 14.3% (3/21) to 95.2% (20/21). Carestart Malaria Pf/Pan (pLDH) Ag G0121, a pLDH-based RDT (PfLDH and pLDH), showed the highest sensitivities to P. falciparum (98.7%, 78/79), P. vivax (94.6%, 35/37), P. ovale (81.8%, 18/22), and P. malariae (95.2%, 20/21) and meets the requirements for military deployments in malaria-endemic areas.

9.
Dig Dis Sci ; 67(11): 5213-5219, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35244825

RESUMO

BACKGROUND: Treatment options for acute severe ulcerative colitis (ASUC) are limited. Tofacitinib, an approved treatment for moderate to severe ulcerative colitis, could be a potential rescue therapy for ASUC given its rapid onset of action. OBJECTIVE: To evaluate the effectiveness of tofacitinib in hospitalized patients with ASUC refractory to standard therapy in a real-world setting. METHODS: Retrospective observational study of hospitalized adult patients with ASUC treated with tofacitinib between January 2019 and September 2020 at five Canadian centers. We extracted patient demographics, clinical status, biomarkers (C-reactive protein and fecal calprotectin), endoscopic findings, and colectomy-free rate at admission, 30 days, 90 days, and 6 months after tofacitinib initiation. RESULTS: Eight patients with symptoms refractory to standard rescue therapy (corticosteroids ± infliximab if infliximab-naïve prior to admission) were treated with tofacitinib. During index hospitalization, clinical response was observed in 5/8 patients. The median time to discharge post-tofacitinib initiation was 5 days (IQR 5.0-6). At 30 and 90 days, all five responders were in clinical remission. At 6 months, only 3/5 responders remained in clinical remission. The colectomy-free rate was 37.5% during the follow-up period (two colectomies occurred within 30 days; one occurred within 90 days). No drug-related adverse reaction occurred. CONCLUSION: In this small case-series, tofacitinib was an effective rescue therapy in patients with refractory ASUC. These findings need to be evaluated in a randomized controlled trial.


Assuntos
Colite Ulcerativa , Adulto , Humanos , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Infliximab/uso terapêutico , Proteína C-Reativa/metabolismo , Canadá , Complexo Antígeno L1 Leucocitário , Corticosteroides/uso terapêutico , Biomarcadores
10.
J Clin Med ; 11(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35053990

RESUMO

SARS-CoV-2 has caused a large outbreak since its emergence in December 2019. COVID-19 diagnosis became a priority so as to isolate and treat infected individuals in order to break the contamination chain. Currently, the reference test for COVID-19 diagnosis is the molecular detection (RT-qPCR) of the virus from nasopharyngeal swab (NPS) samples. Although this sensitive and specific test remains the gold standard, it has several limitations, such as the invasive collection method, the relative high cost and the duration of the test. Moreover, the material shortage to perform tests due to the discrepancy between the high demand for tests and the production capacities puts additional constraints on RT-qPCR. Here, we propose a PCR-free method for diagnosing SARS-CoV-2 based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling and machine learning (ML) models from salivary samples. Kinetic saliva samples were collected at enrollment and ten and thirty days later (D0, D10 and D30), to assess the classification performance of the ML models compared to the molecular tests performed on NPS specimens. Spectra were generated using an optimized protocol of saliva collection and successive quality control steps were developed to ensure the reliability of spectra. A total of 360 averaged spectra were included in the study. At D0, the comparison of MS spectra from SARS-CoV-2 positive patients (n = 105) with healthy healthcare controls (n = 51) revealed nine peaks that significantly distinguished the two groups. Among the five ML models tested, support vector machine with linear kernel (SVM-LK) provided the best performance on the training dataset (accuracy = 85.2%, sensitivity = 85.1%, specificity = 85.3%, F1-Score = 85.1%). The application of the SVM-LK model on independent datasets confirmed its performances with 88.9% and 80.8% of correct classification for samples collected at D0 and D30, respectively. Conversely, at D10, the proportion of correct classification had fallen to 64.3%. The analysis of saliva samples by MALDI-TOF MS and ML appears as an interesting supplementary tool for COVID-19 diagnosis, despite the mitigated results obtained for convalescent patients (D10).

11.
Diagnostics (Basel) ; 11(8)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34441239

RESUMO

SARS-CoV-2 outbreak led to unprecedented innovative scientific research to preclude the virus dissemination and limit its impact on life expectancy. Waiting for the collective immunity by vaccination, mass-testing, and isolation of positive cases remain essential. The development of a diagnosis method requiring a simple and non-invasive sampling with a quick and low-cost approach is on demand. We hypothesized that the combination of saliva specimens with MALDI-TOF MS profiling analyses could be the winning duo. Before characterizing MS saliva signatures associated with SARS-CoV-2 infection, optimization and standardization of sample collection, preparation and storage up to MS analyses appeared compulsory. In this view, successive experiments were performed on saliva from healthy healthcare workers. Specimen sampling with a roll cotton of Salivette® devices appeared the most appropriate collection mode. Saliva protein precipitation with organic buffers did not improved MS spectra profiles compared to a direct loading of samples mixed with acetonitrile/formic acid buffer onto MS plate. The assessment of sample storage conditions and duration revealed that saliva should be stored on ice until MS analysis, which should occur on the day of sampling. Kinetic collection of saliva highlighted reproducibility of saliva MS profiles over four successive days and also at two-week intervals. The intra-individual stability of saliva MS profiles should be a key factor in the future investigation for biomarkers associated with SARS-CoV-2 infection. However, the singularity of MS profiles between individuals will require the development of sophisticated bio-statistical analyses such as machine learning approaches. MALDI-TOF MS profiling of saliva could be a promising PCR-free tool for SARS-CoV-2 screening.

12.
Diagnostics (Basel) ; 11(8)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34441446

RESUMO

BACKGROUND: A previous study demonstrated the performance of the Salivette® (SARSTEDT, Numbrecht, Germany) as a homogeneous saliva collection system to diagnose COVID-19 by RT-qPCR, notably for symptomatic and asymptomatic patients. However, for convalescent patients, the corroboration of molecular detection of SARS-CoV-2 in paired nasopharyngeal swabs (NPS) and saliva samples was unsatisfactory. OBJECTIVES: The aim of the present work was to assess the concordance level of SARS-CoV-2 detection between paired sampling of NPSs and saliva collected with Salivette® at two time points, with ten days of interval. RESULTS: A total of 319 paired samples from 145 outpatients (OP) and 51 healthcare workers (HW) were collected. Unfortunately, at day ten, 73 individuals were lost to follow-up, explaining some kinetic missing data. Due to significant waiting rates at hospitals, most of the patients ate and/or drank while waiting for their turn. Consequently, mouth washing was systematically proposed prior to saliva collection. None of the HW were diagnosed as SARS-CoV-2 positive using NPS or saliva specimens at both time points (n = 95) by RT-qPCR. The virus was detected in 56.3% (n = 126/224) of the NPS samples from OP, but solely 26.8% (n = 60/224) of the paired saliva specimens. The detection of the internal cellular control, the human RNase P, in more than 98% of the saliva samples, underlined that the low sensitivity of saliva specimens (45.2%) for SARS-CoV-2 detection was not attributed to an improper saliva sample storing or RNA extraction. CONCLUSIONS: This work revealed that mouth washing decreased viral load of buccal cavity conducting to impairment of SARS-CoV-2 detection. Viral loads in saliva neo-produced appeared insufficient for molecular detection of SARS-CoV-2. At the time when saliva tests could be a rapid, simple and non-invasive strategy to assess large scale schoolchildren in France, the determination of the performance of saliva collection becomes imperative to standardize procedures.

13.
Pharmaceutics ; 13(8)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34452235

RESUMO

BACKGROUND: Artemisinin-based combination therapy (ACT) was recommended to treat uncomplicated falciparum malaria. Unlike the situation in Asia where resistance to ACT has been reported, artemisinin resistance has not yet emerged in Africa. However, some rare failures with ACT or patients continuing to be parasitaemic on day 3 after ACT treatment have been reported in Africa or in travellers returning from Africa. Three mutations (G50E, R100K, and E107V) in the pfcoronin gene could be responsible for artemisinin resistance in Africa. METHODS: The aims of this study were first to determine the prevalence of mutations in the pfcoronin gene in African P. falciparum isolates by Sanger sequencing, by targeting the 874 samples collected from patients hospitalised in France after returning from endemic areas in Africa between 2018 and 2019, and secondly to evaluate their association with in vitro reduced susceptibility to standard quinoline antimalarial drugs, including chloroquine, quinine, mefloquine, desethylamodiaquine, lumefantrine, piperaquine, and pyronaridine. RESULTS: The three mutations in the pfcoronin gene (50E, 100K, and 107V) were not detected in the 874 P. falciparum isolates. Current data show that another polymorphism (P76S) is present in many countries of West Africa (mean prevalence of 20.7%) and Central Africa (11.9%) and, rarely, in East Africa (4.2%). This mutation does not appear to be predictive of in vitro reduced susceptibility to quinolines, including artemisinin derivative partners in ACT such as amodiaquine, lumefantrine, piperaquine, pyronaridine, and mefloquine. Another mutation (V62M) was identified at low prevalence (overall prevalence of 1%). CONCLUSIONS: The 76S mutation is present in many African countries with a prevalence above 10%. It is reassuring that this mutation does not confer in vitro resistance to ACT partners.

14.
FASEB J ; 35(8): e21773, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34324735

RESUMO

Acute hypoxia has previously been suggested to potentiate resistance training-induced hypertrophy by activating satellite cell-dependent myogenesis rather than an improvement in protein balance in human. Here, we tested this hypothesis after a 4-week hypoxic vs normoxic resistance training protocol. For that purpose, 19 physically active male subjects were recruited to perform 6 sets of 10 repetitions of a one-leg knee extension exercise at 80% 1-RM 3 times/week for 4 weeks in normoxia (FiO2 : 0.21; n = 9) or in hypoxia (FiO2 : 0.135, n = 10). Blood and skeletal muscle samples were taken before and after the training period. Muscle fractional protein synthetic rate was measured over the whole period by deuterium incorporation into the protein pool and muscle thickness by ultrasound. At the end of the training protocol, the strength gain was higher in the hypoxic vs the normoxic group despite no changes in muscle thickness and in the fractional protein synthetic rate. Only early myogenesis, as assessed by higher MyoD and Myf5 mRNA levels, appeared to be enhanced by hypoxia compared to normoxia. No effects were found on myosin heavy chain expression, markers of oxidative metabolism and lactate transport in the skeletal muscle. Though the present study failed to unravel clearly the mechanisms by which hypoxic resistance training is particularly potent to increase muscle strength, it is important message to keep in mind that this training strategy could be effective for all athletes looking at developing and optimizing their maximal muscle strength.


Assuntos
Proteínas Musculares/metabolismo , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Oxigênio/metabolismo , Treinamento de Força/métodos , Regulação da Expressão Gênica , Humanos , Masculino , Músculo Esquelético/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Satélites de Músculo Esquelético/fisiologia , Adulto Jovem
15.
J Oral Microbiol ; 13(1): 1920226, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33986939

RESUMO

Background: The gold standard for COVID-19 diagnosis relies on quantitative reverse-transcriptase polymerase-chain reaction (RT-qPCR) from nasopharyngeal swab (NPS) specimens, but NPSs present several limitations. The simplicity, low invasive and possibility of self-collection of saliva imposed these specimens as a relevant alternative for SARS-CoV-2 detection. However, the discrepancy of saliva test results compared to NPSs made of its use controversial. Here, we assessed Salivettes®, as a standardized saliva collection device, and compared SARS-CoV-2 positivity on paired NPS and saliva specimens. Methods: A total of 303 individuals randomly selected among those investigated for SARS-CoV-2 were enrolled, including 30 (9.9%) patients previously positively tested using NPS (follow-up group), 90 (29.7%) mildly symptomatic and 183 (60.4%) asymptomatic. Results: The RT-qPCR revealed a positive rate of 11.6% (n = 35) and 17.2% (n = 52) for NPSs and saliva samples, respectively. The sensitivity and specificity of saliva samples were 82.9% and 91.4%, respectively, using NPS as reference. The highest proportion of discordant results concerned the follow-up group (33.3%). Although the agreement exceeded 90.0% in the symptomatic and asymptomatic groups, 17 individuals were detected positive only in saliva samples, with consistent medical arguments. Conclusion Saliva collected with Salivette® was more sensitive for detecting symptomatic and pre-symptomatic infections.

16.
Lung Cancer ; 157: 40-47, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33980420

RESUMO

OBJECTIVES: Immune checkpoint inhibitors have become the standard of care for metastatic non-small-cell lung cancer (NSCLC) progressing during or after platinum-based chemotherapy. Real-world clinical practice tends to represent more diverse patient characteristics than randomized clinical trials. We sought to evaluate overall survival (OS) outcomes in the total study population and in key subsets of patients who received nivolumab for previously treated advanced NSCLC in real-world settings in France, Germany, or Canada. MATERIALS AND METHODS: Data were pooled from two prospective observational cohort studies, EVIDENS and ENLARGE, and a retrospective registry in Canada. Patients included in this analysis were aged ≥18 years, had stage IIIB/IV NSCLC, and received nivolumab after at least one prior line of systemic therapy. OS was estimated in the pooled population and in various subgroups using the Kaplan-Meier method. Timing of data collection varied across cohorts (2015-2019). RESULTS: Of the 2585 patients included in this analyses, 1235 (47.8 %) were treated in France, 881 (34.1 %) in Germany, and 469 (18.1 %) in Canada. Median OS for the total study population was 11.3 months (95 % CI: 10.5-12.2); this was similar across France, Germany, and Canada. The OS rate was 49 % at 1 year and 28 % at 2 years for the total study population. In univariable Cox analyses, the presence of epidermal growth factor receptor mutations in nonsquamous disease, liver, or bone metastases were associated with significantly shorter OS, whereas tumor programmed death ligand 1 expression and Eastern Cooperative Oncology Group performance status 0-1 were associated with significantly prolonged OS. Similar OS was noted across subgroups of age and prior lines of therapy. CONCLUSION: OS rates in patients receiving nivolumab for previously treated advanced NSCLC in real-world clinical practice closely mirrored those in phase 3 studies, suggesting similar effectiveness of nivolumab in clinical trials and clinical practice.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adolescente , Adulto , Canadá , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , França/epidemiologia , Alemanha/epidemiologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico , Estudos Retrospectivos
17.
Emerg Infect Dis ; 27(6): 1697-1700, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34013869

RESUMO

Anopheles stephensi mosquitoes share urban breeding sites with Aedes aegypti and Culex quinquefasciatus mosquitoes in the Republic of Djibouti. We present evidence that A. stephensi mosquitoes might be responsible for an increase in malaria incidence in this country. We also document resistance of Plasmodium falciparum to dihydroartemisinin/piperaquine.


Assuntos
Aedes , Anopheles , Culex , Malária , Animais , Surtos de Doenças , Djibuti , Malária/epidemiologia
18.
Pharmaceuticals (Basel) ; 14(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918981

RESUMO

Half the human population is exposed to malaria. Plasmodium falciparum antimalarial drug resistance monitoring and development of new drugs are major issues related to the control of malaria. Methylene blue (MB), the oldest synthetic antimalarial, is again a promising drug after the break of its use as an antimalarial drug for more than 80 years and a potential partner for triple combination. Very few data are available on the involvement of polymorphisms on genes known to be associated with standard antimalarial drugs and parasite in vitro susceptibility to MB (cross-resistance). In this context, MB susceptibility was evaluated against 482 isolates of imported malaria from Africa by HRP2-based ELISA chemosusceptibility assay. A total of 12 genes involved in antimalarial drug resistance (Pfcrt, Pfdhfr, Pfmdr1, Pfmdr5, Pfmdr6, PfK13, Pfubq, Pfcarl, Pfugt, Pfact, Pfcoronin, and copy number of Pfpm2) were sequenced by Sanger method and quantitative PCR. On the Pfmdr1 gene, the mutation 86Y combined with 184F led to more susceptible isolates to MB (8.0 nM vs. 11.6 nM, p = 0.03). Concerning Pfmdr6, the isolates bearing 12 Asn repetitions were more susceptible to MB (4.6 nM vs. 11.6 nM, p = 0.005). None of the polymorphisms previously described as involved in antimalarial drug resistance was shown to be associated with reduced susceptibility to MB. Some genes (particularly PfK13, Pfugt, Pfact, Pfpm2) did not present enough genetic variability to draw conclusions about their involvement in reduced susceptibility to MB. None of the polymorphisms analyzed by multiple correspondence analysis (MCA) had an impact on the MB susceptibility of the samples successfully included in the analysis. It seems that there is no in vitro cross-resistance between MB and commonly used antimalarial drugs.

19.
Sports (Basel) ; 8(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33217937

RESUMO

BACKGROUND: Benefits of sprint interval training performed in hypoxia (SIH) compared to normoxia (SIN) have been assessed by studies mostly conducted around 3000 m of simulated altitude. The present study aims to determine whether SIH at an altitude as high as 4000 m can elicit greater adaptations than the same training at 2000 m, 3000 m or sea-level. METHODS: Thirty well-trained endurance male athletes (18-35 years old) participated in a six-week repeated sprint interval training program (30 s all-out sprint, 4 min 30 s recovery; 4-9 repetitions, 2 sessions/week) at sea-level (SL, n = 8), 2000 m (FiO2 16.7%, n = 8), 3000 m (FiO2 14.5%, n = 7) or 4000 m (FiO2 13.0%, n = 7). Aerobic and anaerobic exercise components were evaluated by an incremental exercise test, a 600 kJ time trial and a Wingate test before and after the training program. RESULTS: After training, peak power output (PPO) during the incremental exercise test increased (~6%) without differences between groups. The lactate threshold assessed by Dmax increased at 2000 m (+14 ± 12 W) and 4000 m (+12 ± 11 W) but did not change at SL and 3000 m. Mean power during the Wingate test increased at SL, 2000 m and 4000 m, although peak power increased only at 4000 m (+38 ± 38 W). CONCLUSIONS: The present study indicates that SIH using 30 s sprints is as efficient as SIN for improving aerobic and anaerobic qualities. Additional benefits such as lactate-related adaptations were found only in SIH and Wingate peak power only increased at 4000 m. This finding is of particular interest for disciplines requiring high power output, such as in very explosive sports.

20.
Int J Antimicrob Agents ; 56(6): 106190, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33045351

RESUMO

Due to resistance to chloroquine and sulfadoxine/pyrimethamine, treatment for uncomplicated Plasmodium falciparum malaria switched to artemisinin-based combination therapy (ACT) in 2006 in Senegal. Several mutations in the gene encoding the kelch13 helix (pfk13-propeller) have been identified as associated with in vitro and in vivo artemisinin resistance in Southeast Asia. Additionally, three mutations in the pfcoronin gene (G50E, R100K and E107V) have been identified in two culture-adapted Senegalese field isolates that became resistant in vitro to artemisinin after 4 years of intermittent selection with dihydroartemisinin. The aims of this study were to assess the prevalence of pfcoronin and pfk13 mutations in Senegalese field isolates from Dakar and to investigate their association with artemisinin derivative clinical failures. A total of 348 samples of P. falciparum from 327 patients, collected from 2015-2019 in Dakar, were successfully analysed. All sequences had wild-type pfk13 allele. The three mutations (G50E, R100K and E107V), previously identified in parasites with reduced susceptibility to artemisinin, were not found in this study, but a new mutation (P76S) was detected (mean prevalence 16.2%). The P76S mutation was identified in 5 (31.3%) of 16 isolates collected from patients still parasitaemic on Day 3 after ACT treatment and in 31 samples (15.3%) among 203 patients considered successfully cured. There was no significant association between in vivo reduced efficacy to artemisinin derivatives and the P76S mutation (P = 0.151, Fisher's exact test). These data suggest that polymorphisms in pfk13 and pfcoronin are not the best predictive markers for artemisinin resistance in Senegal.


Assuntos
Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Doxiciclina/uso terapêutico , Quimioterapia Combinada , Humanos , Lumefantrina/uso terapêutico , Proteínas dos Microfilamentos/genética , Plasmodium falciparum/isolamento & purificação , Polimorfismo de Nucleotídeo Único/genética , Proteínas de Protozoários/genética , Senegal
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