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Chamaecrista diphylla (L.) Greene (Fabaceae/Caesalpiniaceae) is a herbaceous plant that is widely distributed throughout the Americas. Plants from this genus have been used in traditional medicine as a laxative, to heal wounds, and to treat ulcers, snake and scorpion bites. In the present study, we investigated the chemical composition of Chamaecrista diphylla leaves through a mass spectrometry molecular network approach. The oxygen radical absorbance capacity (ORAC) for the ethanolic extract, enriched fractions and isolated compounds was assessed. Overall, thirty-five compounds were annotated for the first time in C. diphylla. Thirty-two of them were reported for the first time in the genus. The isolated compounds 9, 12, 24 and 33 showed an excellent antioxidant capacity, superior to the extract and enriched fractions. Bond dissociation energy calculations were performed to explain and sustain the antioxidant capacity found. According to our results, the leaves of C. diphylla represent a promising source of potent antioxidant compounds.
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Stryphnodendron pulcherrimum is a species known to have a high content of tannins. Accordingly, its preparations are used in southern Pará, Brazil, for their anti-inflammatory and antimicrobial activities, but so far, its chemical profile composition remains essentially unknown. We herein describe the compounds present in a hydro-acetonic extract from S. pulcherrimum leaves as revealed by dereplication via ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry. The data were combined with spectral organization, spectral matching through the Global Natural Products Social platform, in silico annotation and taxonomical ponderation. Several types of phenolic compounds were identified such as gallic acids, flavan-3-ols and flavone-like compounds. From these, 5 have been recently reported by our group, whereas 44 are reported here for the first time in this tree species, and 41 (out of 49) for this genus. The results highlight the possible role of Stryphnodendron pulcherrimum as a renewable source for natural bioactive products with potential pharmaceutical applications.
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The main challenge of plant chemical diversity exploration is how to develop tools to study exhaustively plant tissues. Their sustainable sourcing is a limitation as bioguided strategies and dereplication need quite large amounts of plant material. We examine if alternative solutions could overcome these difficulties by obtaining a secure, sustainable, and scalable source of tissues able to biosynthesize an array of metabolites. As this approach would be as independent of the botanical origin as possible, we chose eight plant species from different families. We applied a four steps culture establishment procedure, monitoring targeted compounds through mass spectrometry-based analytical methods. We also characterized the capacities of leaf explants in culture to produce diverse secondary metabolites. In vitro cultures were successfully established for six species with leaf explants still producing a diversity of compounds after the culture establishment procedure. Furthermore, explants from leaves of axenic plantlets were also analyzed. The detection of marker compounds was confirmed after six days in culture for all tested species. Our results show that the first stage of this approach aiming at easing exploration of plant chemodiversity was completed, and leaf tissues could offer an interesting alternative providing a constant source of natural compounds.
Assuntos
Produtos Biológicos/metabolismo , Folhas de Planta/metabolismo , Plantas/metabolismo , Produtos Biológicos/química , Espectrometria de Massas , Folhas de Planta/química , Plantas/químicaRESUMO
The screening and testing of extracts against a variety of pharmacological targets in order to benefit from the immense natural chemical diversity is a concern in many laboratories worldwide. And several successes have been recorded in finding new actives in natural products, some of which have become new drugs or new sources of inspiration for drugs. But in view of the vast amount of research on the subject, it is surprising that not more drug candidates were found. In our view, it is fundamental to reflect upon the approaches of such drug discovery programs and the technical processes that are used, along with their inherent difficulties and biases. Based on an extensive survey of recent publications, we discuss the origin and the variety of natural chemical diversity as well as the strategies to having the potential to embrace this diversity. It seemed to us that some of the difficulties of the area could be related with the technical approaches that are used, so the present review begins with synthetizing some of the more used discovery strategies, exemplifying some key points, in order to address some of their limitations. It appears that one of the challenges of natural product-based drug discovery programs should be an easier access to renewable sources of plant-derived products. Maximizing the use of the data together with the exploration of chemical diversity while working on reasonable supply of natural product-based entities could be a way to answer this challenge. We suggested alternative ways to access and explore part of this chemical diversity with in vitro cultures. We also reinforced how important it was organizing and making available this worldwide knowledge in an "inventory" of natural products and their sources. And finally, we focused on strategies based on synthetic biology and syntheses that allow reaching industrial scale supply. Approaches based on the opportunities lying in untapped natural plant chemical diversity are also considered.
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We obtained health surveillance epidemiologic data on malaria among French military personnel deployed to French Guiana during 1998-2008. Incidence of Plasmodium vivax malaria increased and that of P. falciparum remained stable. This new epidemiologic situation has led to modification of malaria treatment for deployed military personnel.
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Quimioprevenção/métodos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Plasmodium falciparum/fisiologia , Plasmodium vivax/fisiologia , Animais , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Surtos de Doenças/prevenção & controle , Reservatórios de Doenças/parasitologia , Guiana Francesa/epidemiologia , Humanos , Incidência , Insetos Vetores/parasitologia , Estudos Longitudinais , Malária Falciparum/tratamento farmacológico , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Malária Falciparum/transmissão , Malária Vivax/tratamento farmacológico , Malária Vivax/epidemiologia , Malária Vivax/prevenção & controle , Malária Vivax/transmissão , Militares , Plasmodium falciparum/efeitos dos fármacos , Plasmodium vivax/efeitos dos fármacosRESUMO
To perform epidemiological surveillance during deployments, the French military health service has developed a real-time surveillance approach. The objective was to identify the benefits and problems of this approach. A prototype of real-time surveillance has been set up in French Guiana since 2004. Its permanent evaluation has allowed identifying strengths and weaknesses. The experience has permitted expansion of the concept to French forces in Djibouti and also development of a global approach for the whole French armed forces. Real-time surveillance has shown its usefulness for early warning during different real and simulated situations. Functional and architectural choices have permitted interoperability with allied nations. However, the information produced was only the first step of the diagnostic epidemiological situation followed by other investigations. This first step of development has highlighted the required complementarity with traditional epidemiological surveillance.
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Surtos de Doenças/prevenção & controle , Militares , Vigilância da População/métodos , Interpretação Estatística de Dados , França/epidemiologia , Guiana Francesa , HumanosRESUMO
BACKGROUND: A dengue fever outbreak occured in French Guiana in 2006. The objectives were to study the value of a syndromic surveillance system set up within the armed forces, compared to the traditional clinical surveillance system during this outbreak, to highlight issues involved in comparing military and civilian surveillance systems and to discuss the interest of syndromic surveillance for public health response. METHODS: Military syndromic surveillance allows the surveillance of suspected dengue fever cases among the 3,000 armed forces personnel. Within the same population, clinical surveillance uses several definition criteria for dengue fever cases, depending on the epidemiological situation. Civilian laboratory surveillance allows the surveillance of biologically confirmed cases, within the 200,000 inhabitants. RESULTS: It was shown that syndromic surveillance detected the dengue fever outbreak several weeks before clinical surveillance, allowing quick and effective enhancement of vector control within the armed forces. Syndromic surveillance was also found to have detected the outbreak before civilian laboratory surveillance. CONCLUSION: Military syndromic surveillance allowed an early warning for this outbreak to be issued, enabling a quicker public health response by the armed forces. Civilian surveillance system has since introduced syndromic surveillance as part of its surveillance strategy. This should enable quicker public health responses in the future.
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Dengue/epidemiologia , Surtos de Doenças , Militares , Vigilância da População/métodos , Dengue/diagnóstico , Dengue/prevenção & controle , Surtos de Doenças/prevenção & controle , Diagnóstico Precoce , Guiana Francesa/epidemiologia , Humanos , Medicina MilitarRESUMO
To investigate if the characteristics of human intestinal Escherichia coli are changing with the environment of the host, we studied intestinal E. coli from subjects having recently migrated from a temperate to a tropical area. We determined the phylogenetic group, the prevalence of the antibiotic resistance, the presence of integrons and the strain diversity in faecal isolates from 25 subjects originally from metropolitan France and expatriated to French Guyana. These characteristics were compared with those of 25 previously studied Wayampi Amerindian natives of French Guyana and from 25 metropolitan French residents. The three groups of subjects were matched for age and sex, had not taken antibiotics for at least 1 month, nor had been hospitalized within the past year. In all, the characteristics of intestinal E. coli from Expatriates were intermediate between those found in residents from metropolitan France and those found in natives of French Guyana. Prevalence of carriage of resistant Gram-negative bacteria in Expatriates was intermediate between French residents and Wayampi as were the prevalence of integrons in E. coli (12.3% versus 16.3% and 7.8% respectively), and the intra-host diversity of E. coli (2.3 strains/subject versus 1.9 and 3.1, respectively); lastly, in Expatriates, the prevalence of carriage of phylogenetic group B2 strains was lower than in French residents (16% versus 56%, P = 0.005), while carriage of phylogenetic group A strains was lower than in Wayampi (56% versus 88%, P = 0.03). Our results suggest that the composition of the commensal intestinal flora of humans is not static but changes dynamically in response to new environmental conditions.
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Portador Sadio/microbiologia , Escherichia coli/classificação , Escherichia coli/genética , Trato Gastrointestinal/microbiologia , Farmacorresistência Bacteriana/genética , Emigração e Imigração , Escherichia coli/efeitos dos fármacos , Feminino , França , Guiana Francesa , Humanos , Indígenas Sul-Americanos/etnologia , Masculino , Testes de Sensibilidade Microbiana , Filogenia , ViagemRESUMO
BACKGROUND: To evaluate a new military syndromic surveillance system (2SE FAG) set up in French Guiana. METHODS: The evaluation was made using the current framework published by the Centers for Disease Control and Prevention, Atlanta, USA. Two groups of system stakeholders, for data input and data analysis, were interviewed using semi-structured questionnaires to assess timeliness, data quality, acceptability, usefulness, stability, portability and flexibility of the system. Validity was assessed by comparing the syndromic system with the routine traditional weekly surveillance system. RESULTS: Qualitative data showed a degree of poor acceptability among people who have to enter data. Timeliness analysis showed excellent case processing time, hindered by delays in case reporting. Analysis of stability indicated a high level of technical problems. System flexibility was found to be high. Quantitative data analysis of validity indicated better agreement between syndromic and traditional surveillance when reporting on dengue fever cases as opposed to other diseases. CONCLUSIONS: The sophisticated technical design of 2SE FAG has resulted in a system which is able to carry out its role as an early warning system. Efforts must be concentrated on increasing its acceptance and use by people who have to enter data and decreasing the occurrence of the frequency of technical problems.
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Surtos de Doenças , Medicina Militar , Militares , Vigilância da População/métodos , Saúde Pública , Medicina Tropical , Feminino , Guiana Francesa , Humanos , Masculino , Medicina Militar/métodos , Militares/estatística & dados numéricos , Pesquisa Qualitativa , Inquéritos e Questionários , Síndrome , Fatores de Tempo , Medicina Tropical/métodos , Reino UnidoRESUMO
An outbreak of malaria occurred among 62 policemen following an operation against illegal gold panning in French Guiana. A retrospective cohort study was conducted. The objectives were to describe the outbreak and to identify factors related to the cases. The total number of initial cases was 37. Both Plasmodium falciparum and Plasmodium vivax were detected. Twenty-seven policemen presented with one to four recurrences. In bivariate analysis, factors related to malaria were a "medium to high" level of mosquito bites pollution at night, late washing in the evening and wearing a nonimpregnated Battle Dress Uniform (BDU). This investigation confirmed the low level of compliance with chemoprophylaxis among individuals on long-term assignment in French Guiana. Compliance with mosquito protection measures was satisfactory except for the use of impregnated BDU. Several recommendations were provided. Therefore, this outbreak reminds us that malaria remains a public health problem in French Guiana.
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Surtos de Doenças , Malária/etnologia , Polícia , Adulto , Feminino , França/etnologia , Guiana Francesa/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
Between 1967 and 1987 in the Southern Marquesas, a remote archipelago in French Polynesia, the detection rate of leprosy was 48.9 per 100,000 when it was 8.6 per 100,000 for French Polynesia as a whole. In 1988, a program of chemoprophylaxis of leprosy with a single dose of 25 mg/kg rifampin was implemented, and 2751 persons (98.7% of the population) were treated in the Southern Marquesas. In addition, 678 South Marquesans and 2466 members of their families living in the Northern Marquesas and in the Society Archipelago, received the same chemoprophylaxis. Among 2676 persons studied in the Southern Marquesas (97.4% of the treated population), 130 had elevated IgM anti-phenolic glycolipid-I antibodies by ELISA without any evidence of leprosy. The onset of a skin lesion of borderline leprosy in a boy 3 months after chemoprophylaxis raises the question of the nature of such a skin lesion and, indirectly, of the effectiveness of the chemoprophylaxis