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1.
Rhinology ; 59(5): 470-474, 2021 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-34398939

RÉSUMÉ

BACKGROUND: Cystic fibrosis (CF) carriers seem to have a higher risk to develop chronic rhino-sinusitis (CRS), although the full underlying mechanisms are unknown. Ion concentrations in nasal airway surface liquid (ASL) may be influenced by the heterozygosity for CF gene mutation, with possible impacts on the development of CRS. METHODS: A cheap and feasible standardized technique was designed to measure the ion levels in nasal ASL. With this purpose we collected, under basal conditions, samples from the nasal cavity of 165 adults: 14 homozygous for CF, 83 carriers and 68 healthy controls. Sodium (Na) and Chlorine (Cl) concentrations were then evaluated among different groups. RESULTS: Statistical analysis revealed a significant difference of Na and Cl values between controls and carriers and between controls and homozygotes. Receiver operating characteristic (ROC) curves and derived indicators (Youden's index and Area Under the Curve, AUC) were used to further evaluate the diagnostic capability of Na and Cl concentrations to differentiate heterozygotes from controls. ROC curves demonstrated that the optimal diagnostic cut-off value of Na is at 124, and the optimal cut-off value of Cl is at 103,2. CONCLUSION: ASL sampling can be considered a new diagnostic tool for providing quantitative information on nasal ion composition. According to our findings, Na and Cl concentrations of nasal ASL could represent a useful tool to assess heterozygotes and healthy controls.


Sujet(s)
Mucoviscidose , Sinusite , Adulte , Mucoviscidose/génétique , Hétérozygote , Humains , Appareil respiratoire , Sodium
2.
Int J Lab Hematol ; 39(6): 663-670, 2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-28990291

RÉSUMÉ

INTRODUCTION: Recent automated hematology analyzers (HAs) can identify and report nucleated red blood cells (NRBC) count as a separate population out of white blood cells (WBC). The aim of this study was to investigate the analytical performances of NRBC enumeration on five top of the range HAs. METHODS: We evaluated the within-run and between-day precision, limit of blank (LoB), limit of detection (LoD), and limit of quantitation (LoQ) of XE-2100 and XN-module (Sysmex), ADVIA 2120i (Siemens), BC-6800 (Mindray), and UniCel DxH 800 (Beckman Coulter). Automated NRBC counts were also compared with optical microscopy (OM). RESULTS: The limits of detection for NRBC of the BC-6800, XN-module, XE-2100, UniCel DxH 800, and ADVIA 2120i are 0.035×109 /L, 0.019×109 /L, 0.067×109 /L, 0.038×109 /L, and 0.167×109 /L, respectively. Our data indicated excellent performance in terms of precision. The agreement with OM was excellent for BC-6800, XN-module, and XE-2100 (Bias 0.023, 0.019, and 0.033×109 /L, respectively). ADVIA 2120i displayed a significant constant error and UniCel DxH 800 both proportional and small constant error. CONCLUSION: Regards to NRBC counting, the performances shown by BC-6800, XN-module, and XE-2100 are excellent also a low count, ADVIA 2120i and UniCel DxH 800 need to be improved.


Sujet(s)
Érythroblastes/anatomopathologie , Tests hématologiques/instrumentation , Femelle , Tests hématologiques/méthodes , Humains , Mâle
3.
Int J Lab Hematol ; 39(6): 645-652, 2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-28975714

RÉSUMÉ

BACKGROUND: The aims of this study were to compare the diagnostic accuracy of blood smear review criteria, by means of three different panel rules, those proposed by: the International Consensus Group for Hematology [41-ICGH rules], the Italian Survey [IS rules] and the Working Group on Hematology-SIBioC (WGH) consensus rules (WGH rules). METHODS: This study is based on 2707 peripheral blood (PB) samples referred for routine hematological testing to the WGH-associated laboratories displaced all over the Italian territory. The PB samples were processed on seven different hematology analyzers (HAs): Advia 2120i, XE-2100, BC-6800, ABX Pentra, XN-1000, Cell-DYN Sapphire, and DxH800, respectively. All the results provided by the HAs were analyzed through the application of three different blood smear review criteria: that is, the 41-ICGH, IS, and WGH rules. Finally, data were compared with those obtained by optical microscopy (OM), as the current gold standard. RESULTS: The overall the agreement OM classification with ICGH, IS, and WGH panel rules is 0.83, 0.83, and 0.85, respectively. The false negatives are 2.1%, 3.0%, and 2.9%, while false positives are 15.1%, 13.7%, and 11.7%, respectively. All the seven HAs showed variable interinstrument performance, as three different criteria for OM review were adopted on each of them from time to time. CONCLUSION: These results presented show that the customization of validation rules is necessary for enhancing the quality of hematological testing and optimizing workflow.


Sujet(s)
Tests hématologiques/instrumentation , Tests hématologiques/méthodes , Tests hématologiques/normes , Femelle , Humains , Italie , Mâle
4.
B-ENT ; 12(3): 245-247, 2016.
Article de Anglais | MEDLINE | ID: mdl-29727131

RÉSUMÉ

The aim of this paper is to present a unique case of neck-necrotizing fasciitis caused by Listeria Monocytogenes in a young woman, successfully treated by surgery and IV antibiotic therapy. Necrotizing fasciitis is a rare, rapidly progressing and potentially life-threatening infection that infrequently occurs in the head and neck region. Pathogens involved in necrotizing fasciitis are heterogeneous and include aerobic and anaerobic bacteria. To the best of our knowledge, this is the only case of neck necrotizing fasciitis caused by Listeria Monocytogenes studied in literature so far.


Sujet(s)
Fasciite nécrosante/microbiologie , Infections à Listeria/diagnostic , Adulte , Antibactériens/usage thérapeutique , Fasciite nécrosante/thérapie , Femelle , Humains , Lévofloxacine/usage thérapeutique , Listeria monocytogenes , Infections à Listeria/thérapie , Cou , Infections opportunistes/microbiologie
5.
Rev. bras. plantas med ; 18(2): 558-562, 2016. graf
Article de Portugais | LILACS | ID: lil-787954

RÉSUMÉ

RESUMO O presente trabalho teve como objetivo principal avaliar o potencial do uso do óleo essencial de Aloysia citriodora no controle in vitro de Fusarium sp., isolado de plântulas de beterraba infectadas com o mesmo. O trabalho foi realizado por meio de dois experimentos: um sobre o efeito do óleo essencial no crescimento micelial, e outro sobre o efeito na germinação de conídios do fungo. No primeiro trabalho, avaliou-se em delineamento inteiramente ao acaso, o efeito das concentrações 0,0155%; 0,0315%; 0,0625%; 0,125%; 0,250% e 0,500% do óleo essencial de A. citriodora em placas de Petri® com meio de cultivo BDA, mais a testemunha, com meio BDA puro. Cada placa foi considerada uma repetição, as quais foram incubadas a 24ºC±1ºC e submetidas a fotoperíodo de doze horas. Avaliou-se o crescimento radial do patógeno em função do crescimento micelial do patógeno quando este atingia as bordas da primeira placa. No segundo experimento, as mesmas concentrações foram testadas, nas mesmas condições de incubação, no entanto, em lâminas de microscopia com meio BD. Utilizou-se delineamento inteiramente ao acaso, sendo considerada como unidade experimental cada lâmina utilizada. Avaliou-se 24 horas após a incubação, em microscópio óptico, a germinação dos primeiros vinte conídios visualizados a partir do canto esquerdo superior para o direito. Os resultados do segundo experimento foram expressos em porcentagem de germinação de conídios. Os resultados obtidos permitiram concluir que este óleo essencial possui efeito fungistático e fungicida sobre o crescimento micelial e na germinação de conídios de Fusarium sp.. Além disso este efeito é maior em função do aumento da concentração do óleo essencial.


ABSTRACT This study aimed to evaluate the potential use of Aloysia citriodora essential oilisolated from beet seedlings infected with it. The study was performed by conducting two experiments evaluating the effect of the essential oil on mycelial growth and fungus conidia germination. In the first study, in a completely randomized design, the effect concentrations (0.0155%; 0.0315%; 0.0625%; 0.125%; 0.250% and 0.500%) of essential oil of A. citriodorawas evaluated on Petri® dish with a PDA cultivation medium, plus the control, with half pure PDA. Each plate was taken as a repeat, and incubated at 24°C±1°C and a photoperiod of twelve hours. The radial growth of the pathogen, when the first plate was hit by the mycelial growth of the pathogen on its edges was evaluated. In the second experiment, the same concentrations were tested under the same incubationconditions, however, on microscope slides with half PD medium. The design was used completely randomized, each microscope slide used was considered as one experimental unit. Germination of the first 2 conidia strains, viewed from the upper left to the right was evaluated24 hours after incubation, using an optical microscope. The results of the second experiment were expressed as a percentage of conidia germination. The results obtained showed that this essential oil has fungistatic and fungicidal effect on the mycelial growth and at the conidia germination of Fusarium sp., which has a greater effect with increasing concentrations.


Sujet(s)
Huile essentielle/analyse , Lippia/classification , Fusarium/classification , Plantes médicinales/classification , Beta vulgaris/classification , Verbenaceae/classification
6.
Int J Immunopathol Pharmacol ; 28(3): 434-9, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-25875601

RÉSUMÉ

Sinonasal polyposis (SNP) is a chronic inflammatory disease of nasal and paranasal cavities. Human leukocyte antigen-G molecules (HLA-G) are non-classic HLA-I molecules with anti-inflammatory and tolerogenic properties. HLA-G production is mainly induced by interleukin (IL)-10. IL-10 is an anti-inflammatory cytokine that inhibits the production of proinflammatory cytokines and induces HLA-class II down-modulation. Recent studies suggest that HLA-G could play a role in SNP pathogenesis; in SNP patients physiological levels of IL-10 (produced by activated peripheral blood CD14+ monocytes) are not able to induce production of HLA-G. Different mechanisms could justify these findings: genomic or amino-acidic sequence alterations in IL-10 lower IL-10 receptor expression, lower IL-10 receptor affinity, or alterations of the intracellular signal transmission. This study analyzes nucleotidic sequence of IL-10 gene in SNP patients. Sequencing of IL-10 gene shows that the lack of HLA-G production by peripheral blood CD14+ monocytes is not related to alterations in IL-10 gene nucleotidic sequence.


Sujet(s)
Interleukine-10/génétique , Polypes du nez/génétique , Adulte , Cytokines/génétique , Femelle , Antigènes HLA-G/génétique , Antigènes d'histocompatibilité de classe I/génétique , Humains , Antigènes CD14/génétique , Mâle , Monocytes/métabolisme , Récepteurs à l'interleukine-10/génétique
7.
Eur J Med Chem ; 95: 267-76, 2015 May 05.
Article de Anglais | MEDLINE | ID: mdl-25827397

RÉSUMÉ

The development of biocompatible polymeric nanoparticles has become an important strategy for optimizing the therapeutic efficacy of many classical drugs, as it may expand their activities, reduce their toxicity, increase their bioactivity and improve biodistribution. In this study, nanoparticles of Amphotericin B entrapped within poly (lactic-co-glycolic) acid and incorporated with dimercaptosuccinic acid (NANO-D-AMB) as a target molecule were evaluated for their physic-chemical characteristics, pharmacokinetics, biocompatibility and antifungal activity. We found high plasma concentrations of Amphotericin B upon treatment with NANO-D-AMB and a high uptake of nanoparticles in the lungs, liver and spleen. NANO-D-AMB exhibited antifungal efficacy against Paracoccidioides brasiliensis and induced much lower cytotoxicity levels compared to D-AMB formulation in vivo and in vitro. Together, these results confirm that NANO-D-AMB improves Amphotericin B delivery and suggest this delivery system as a potential alternative to the use of Amphotericin B sodium deoxycholate.


Sujet(s)
Amphotéricine B/composition chimique , Amphotéricine B/pharmacologie , Antifongiques/composition chimique , Antifongiques/pharmacologie , Acide désoxycholique/composition chimique , Acide désoxycholique/pharmacologie , Vecteurs de médicaments/composition chimique , Acide lactique/composition chimique , Nanoparticules/composition chimique , Acide polyglycolique/composition chimique , Amphotéricine B/effets indésirables , Amphotéricine B/usage thérapeutique , Animaux , Antifongiques/effets indésirables , Antifongiques/usage thérapeutique , Acide désoxycholique/effets indésirables , Acide désoxycholique/usage thérapeutique , Vecteurs de médicaments/pharmacocinétique , Association médicamenteuse , Libération de médicament , Acide lactique/pharmacocinétique , Test de matériaux , Souris , Paracoccidioides/effets des médicaments et des substances chimiques , Paracoccidioides/physiologie , Blastomycose sud-américaine/traitement médicamenteux , Acide polyglycolique/pharmacocinétique , Copolymère d'acide poly(lactique-co-glycolique) , Sécurité , Succimer/composition chimique , Distribution tissulaire
8.
Int J Immunopathol Pharmacol ; 26(4): 965-71, 2013.
Article de Anglais | MEDLINE | ID: mdl-24355233

RÉSUMÉ

Fine-needle aspiration cytology (FNAC) is a minimally invasive procedure usually well tolerated, easy to perform, quick, cheap and easy to repeat in case of doubts or non-diagnostic results. Echography is also a fast, cheap and non-invasive tool; however, the role of FNAC and echography in the diagnosis of salivary gland pathology is not universally recognised. Three hundred and fifty-seven patients with a cytological diagnosis at FNAC, and 247 of these who were also studied with echography, were enrolled for this retrospective study. The final histopathological diagnoses, obtained after surgery, were then compared to the preoperative FNAC diagnoses and echographic findings. From the analysis of our data, the overall FNAC specificity resulted 93 percent, sensitivity 83 percent, and diagnostic accuracy 92 percent. Echography sensibility was 57.1 percent specificity 98.2 percent, while positive and negative predictive value were respectively 80 percent and 94.8 percent. While echography can be useful in order to provide a better characterization of salivary gland lesions, FNAC can then be considered a safe diagnostic tool with reliable sensitivity and specificity for the assessment of salivary gland pathology and thus for selecting patients and indicating the best surgical treatment.


Sujet(s)
Tumeurs des glandes salivaires/diagnostic , Glandes salivaires/anatomopathologie , Cytoponction , Humains , Études rétrospectives , Tumeurs des glandes salivaires/anatomopathologie , Tumeurs des glandes salivaires/ultrastructure
9.
Br J Cancer ; 107(8): 1286-94, 2012 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-22955853

RÉSUMÉ

BACKGROUND: Recently, we developed an apoptotic assay for expanding the monitoring capabilities of the circulating tumour cells (CTC) test during therapy. An automated platform for computing CTCs was integrated with a mAb (M30) targeting a neoepitope disclosed by caspase cleavage at cytokeratin 18 in early apoptosis; we showed that live CTCs were associated with progression, consistent with enhanced cell migration and invasion. The test was first applied here to mRCC. METHODS: Live/apoptotic CTCs changes were measured in mRCC patients receiving first-line Sunitinib and compared with circulating endothelial cell (CEC) levels. RESULTS: The presence of EpCAM-positive, live CTCs predicts progression in individual mRCC patient, being associated with distant metastasis under first-line Sunitinib. Synchronous detection of CTCs and CEC levels discloses for the first time an association between their dynamic changes and outcome: a rapid increase of the CEC number as early as the first cycle of therapy is associated with CTC decrease in non-progressed patients, whereas a delayed response of CECs is related to higher CTC values in the progressed group indicating treatment failure. CONCLUSION: We demonstrated that a delayed response to antiangiogenic treatment indicated by persistent detection of CECs correlates with persistent live CTCs and more aggressive disease.


Sujet(s)
Inhibiteurs de l'angiogenèse/usage thérapeutique , Cellules endothéliales/anatomopathologie , Indoles/usage thérapeutique , Tumeurs du rein/traitement médicamenteux , Cellules tumorales circulantes/anatomopathologie , Pyrroles/usage thérapeutique , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Apoptose , Marqueurs biologiques tumoraux , Évolution de la maladie , Femelle , Humains , Kératine-18 , Tumeurs du rein/anatomopathologie , Tumeurs du rein/secondaire , Mâle , Adulte d'âge moyen , Études prospectives , Sunitinib , Échec thérapeutique
10.
Audiol Neurootol ; 15(2): 111-5, 2010.
Article de Anglais | MEDLINE | ID: mdl-19657186

RÉSUMÉ

AIMS/HYPOTHESIS: Idiopathic sudden sensorineural hearing loss (ISSNHL) represents an acute inner ear disorder with an overall incidence of 5-20/100000 individuals per year in western countries. No clear causes for this disease have been found so far, but cochlear ischemia has been hypothesized as one of the etiopathological mechanisms. The aim of our study was to assess the role of diabetes and traditional cardiovascular risk factors in the pathogenesis of ISSNHL. MATERIALS/METHODS: Case-control study of 141 patients (75 males/66 females) matched for age and gender. Cases were affected by ISSNHL, defined as a sudden hearing loss > or =30 dB, within 3 frequencies, developing over 72 h. The control group was composed of 271 sex- and age-matched subjects (142 males/129 females) who agreed to participate in this observational study and provided blood samples for laboratory investigations. Cardiovascular risk factors examined were: diabetes mellitus, smoking history, hypercholesterolemia, hypertriglyceridemia and hypertension. RESULTS: On the univariate analysis, diabetes prevalence was higher in the ISSNHL group (15.6%) compared to controls (8.5%) (p = 0.03). Also hypercholesterolemia was significantly more frequent in the ISSNHL group compared to the control population. There were no statistically significant differences between the 2 populations concerning other cardiovascular risk factors. The risk of ISSNHL tended to increase as the number of cardiovascular risk factors increased (p for linear trend = 0.018). CONCLUSIONS: Our findings suggest that diabetes mellitus, hypercholesterolemia and a high burden of cardiovascular risk factors are associated with the risk of ISSNHL.


Sujet(s)
Maladies cardiovasculaires/épidémiologie , Diabète de type 2/épidémiologie , Perte auditive soudaine/épidémiologie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Maladies cardiovasculaires/complications , Études cas-témoins , Causalité , Comorbidité , Femelle , Perte auditive soudaine/étiologie , Humains , Hypercholestérolémie/complications , Hypercholestérolémie/épidémiologie , Hypertension artérielle/complications , Hypertension artérielle/épidémiologie , Hypertriglycéridémie/complications , Hypertriglycéridémie/épidémiologie , Italie , Mâle , Adulte d'âge moyen , Facteurs de risque , Fumer/effets indésirables , Fumer/épidémiologie , Jeune adulte
11.
J Appl Microbiol ; 106(2): 459-66, 2009 Feb.
Article de Anglais | MEDLINE | ID: mdl-19200313

RÉSUMÉ

AIMS: To evaluate the soybean polyphenol glucosides bioconversion to aglycone forms by different beta-glucosidases-producing filamentous fungi to enhance their antioxidant activity. METHODS AND RESULTS: Soybean defatted flour was submitted to solid-state fermentation with Aspergillus niger, Aspergillus niveus and Aspergillus awamori. The fungi studied produced approximately the same beta-glucosidase activity units amount when p-nitrophenyl-beta-d-glucopyranoside was used as substrate for the assay. However, electrophoretic analysis, using 4-methylumbellipheryl-beta-d-glucopyranoside as substrate, showed that beta-glucosidase produced by A. niveus was more active. Fermented methanolic extracts showed an increase in polyphenol and genistein contents and antioxidant activities. The highest genistein content was found in soybean fermented by A. niveus. Methanolic extracts of the soybean fermented by the different fungi showed a similar capacity of scavenging H(2)O(2) generated in vivo by the tumour promoter 12-O-tetradecanoyl phorbol-13-acetate. CONCLUSIONS: A. niveus synthesized a beta-glucosidase with higher specificity to hydrolyse genistin beta-glycosidic bond than those produced by A. awamori and A. niger. SIGNIFICANCE AND IMPACT OF THE STUDY: The utilization of these beta-glucosidases-producing fungi in soybean fermentation processes resulted in the obtaining of methanolic extracts with different antioxidant potentials that could be used either therapeutically or as an antioxidant in nonphysiological oxidative stress conditions, as the one induced in skin by UV radiation.


Sujet(s)
Aspergillus/enzymologie , Cellulases/métabolisme , Flavonoïdes/métabolisme , Farine , Glycine max/composition chimique , Phénols/métabolisme , Animaux , Antioxydants/métabolisme , Fermentation , Microbiologie alimentaire , Génistéine/analyse , Glucosides/métabolisme , Peroxyde d'hydrogène/métabolisme , Souris , Polyphénols , Produits alimentaires à base de soja
12.
Water Sci Technol ; 47(7-8): 275-82, 2003.
Article de Anglais | MEDLINE | ID: mdl-12793690

RÉSUMÉ

An integrated water resource management programme has been under way since 1999 to reduce agricultural water pollution in the River Mincio fluvial park. The experimental part of the programme consisted of: a) a monitoring phase to evaluate the impact of conventional and environmentally sound techniques (Best Management Practices, BMPs) on water quality; this was done on four representative landscape units, where twelve fields were instrumented to monitor the soil, surface and subsurface water quality; b) a modelling phase to extend the results obtained at field scale to the whole territory of the Mincio watershed. For this purpose a GIS developed in the Arc/Info environment was integrated into the CropSyst model. The model had previously been calibrated to test its ability to describe the complexity of the agricultural systems. The first results showed a variable efficiency of the BMPs depending on the interaction between management and pedo-climatic conditions. In general though, the BMPs had positive effects in improving the surface and subsurface water quality. The CropSyst model was able to describe the agricultural systems monitored and its linking with the GIS represented a valuable tool for identifying the vulnerable areas within the watershed.


Sujet(s)
Agriculture , Systèmes d'information géographique , Modèles théoriques , Azote/analyse , Polluants de l'eau/analyse , Italie , Appréciation des risques , Mouvements de l'eau , Pollution de l'eau/prévention et contrôle
13.
J Environ Qual ; 30(4): 1330-40, 2001.
Article de Anglais | MEDLINE | ID: mdl-11476512

RÉSUMÉ

Controlled drainage and wetlands could be very effective practices to control nitrogen pollution in the low-lying agricultural plains of northeast Italy, but they are not as popular as in other countries. An experiment on lysimeters was therefore carried out in 1996-1998, with the double aim of obtaining local information to encourage the implementation of these practices and to gain more knowledge on the effects involved. Controlled drainage + subirrigation and wetlands were all considered as natural systems where alternative water table management could ameliorate water quality, and were compared with a typical water management scheme for crops in the open field. Eight treatments were considered: free drainage on maize (Zea mays L.) and sugarbeet (Beta vulgaris L.), two treatments of controlled drainage on the same crops, and five wetland treatments using common reed [Phragmites australis (Cav.) Trin. ex Steud.], common cattail (Typha latifolia L.), and tufted sedge (Carex elata All.), with different water table or flooding levels. Lysimeters received about 130 g m 2 of N with fertilization and irrigation water, with small differences among treatments. The effects of treatments were more evident for NO3-N concentrations than for the other chemical parameters (total Kjeldahl nitrogen, pH, and electrical conductivity), with significantly different medians among free drainage (33 mg L(-1)), controlled drainage (1.6 and 2.6 mg L(-1)), and wetlands (0.5-0.7 mg L(-1)). Referring to free drainage, NO3-N losses were reduced by 46 to 63% in controlled drainage and 95% in the average of wetlands. Wetlands also reduced losses of total dissolved solids from 253 g m(-2) (average of crop treatments) to 175 g m(-2) (average of wetlands).


Sujet(s)
Agriculture , Azote/analyse , Polluants du sol/analyse , Pollution de l'eau/prévention et contrôle , Alimentation en eau , Catastrophes , Surveillance de l'environnement , Mouvements de l'eau
14.
Water Sci Technol ; 44(11-12): 523-30, 2001.
Article de Anglais | MEDLINE | ID: mdl-11804144

RÉSUMÉ

A study was conducted between December 1997 and December 1998 in NE Italy on a 3,200 m2 surface flow vegetated wetland receiving agricultural drainage water from a cultivated field of about 6 ha and occasional applications of organic wastes. The study aimed at evaluating: 1) biomass and seasonal nitrogen dynamics in above- and below-ground biomass of Phragmites australis Cav. (Trin.) and Typha latifolia (L.) grown in separate zones; 2) the effectiveness of the wetland in removing nutrients and sediments coming from the fields; 3) the possibility that wetland could treat occasional applications of organic wastes and 4) to collect some general information on whether the wetland can receive heavy loads coming from storm water runoff. Monthly observations showed that, in both species, aboveground biomass, nitrogen concentration and nitrogen content reached maximum values in summer and minimum values in winter. The contrary occurred in below-ground biomass. The total input of water in the wetland was 66,000 m3 ha(-1), of which 7,700 were drained. Total nitrogen input was 526 kg ha(-1), of which 58 were discharged out of the wetland.


Sujet(s)
Agriculture , Écosystème , Azote/métabolisme , Poaceae/physiologie , Élimination des déchets liquides/méthodes , Biomasse , Saisons , Mouvements de l'eau
15.
Phytochemistry ; 55(6): 559-65, 2000 Nov.
Article de Anglais | MEDLINE | ID: mdl-11130665

RÉSUMÉ

In the neotropics, one of the last biological frontiers, the major ecological concern should not involve local strategies, but global effects often responsible for irreparable damage. For a holistic approach, angiosperms are ideal model systems dominating most land areas of the present world in an astonishing variety of form and function. Recognition of biogeographical patterns requires new methodologies and entails several questions, such as their nature, dynamics and mechanism. Demographical patterns of families, modelled via species dominance, reveal the existence of South American angiosperm networks converging at the central Brazilian plateau. Biodiversity of habitats, measured via taxonomic uniqueness, reveal higher creative power at this point of convergence than in more peripheral regions. Compositional affinities of habitats, measured via bioconnectivity, reveal the decisive role of ecotones in the exchange or redistribution of information, energy and organisms among the ecosystems. Forming dynamic boundaries, ecotones generate and relay evolutionary novelty, and integrate all neotropical ecosystems into a single vegetation net. Connectivity in such plant webs may depend on mycorrhizal links. If sufficiently general such means of metabolic transfer will require revision of the chemical composition of many plants.


Sujet(s)
Écosystème , Magnoliopsida/physiologie , Modèles biologiques , Conservation des ressources naturelles/méthodes , Services d'information , Magnoliopsida/classification , Amérique du Sud
16.
Mem Inst Oswaldo Cruz ; 95(1): 115-20, 2000.
Article de Anglais | MEDLINE | ID: mdl-10656716

RÉSUMÉ

We live in a "Demon-Haunted World". Human health care requires the ever increasing resistance of pathogens to be confronted by a correspondingly fast rate of discovery of novel antibiotics. One of the possible strategies towards this objective involves the rational localization of bioactive phytochemicals. The conceptual basis of the method consists in the surprisingly little known gearings of natural products with morphology, ecology and evolution of their plant source, i. e. an introspection into the general mechanisms of nature.


Sujet(s)
Facteurs biologiques/métabolisme , Plantes médicinales/métabolisme , Résistance microbienne aux médicaments , Écologie , Magnoliopsida , Phytothérapie
17.
J Clin Pharmacol ; 39(8): 805-10, 1999 Aug.
Article de Anglais | MEDLINE | ID: mdl-10434232

RÉSUMÉ

The absolute bioavailability of clindamycin phosphate vaginal ovule with comparison to a reference treatment of clindamycin phosphate sterile solution, as well as the relative bioavailability of the ovule compared to clindamycin phosphate vaginal cream, was evaluated in 12 healthy adult female volunteers. Subjects were randomly assigned to receive either the ovule or cream formulation intravaginally for 3 consecutive days during the two-way crossover portion of the study. During a third treatment period, all subjects received 100 mg of clindamycin as a 4-minute intravenous infusion of clindamycin phosphate sterile solution (10 mg/mL). Clindamycin concentrations in serum were assayed by a high-performance liquid chromatography method with detection by mass spectrometry. Pharmacokinetic analyses of the serum data indicated low systemic absorption of clindamycin from the vaginal cream (about 4%), consistent with results of previous bioavailability studies. Following intravaginal administration of the clindamycin phosphate ovule, systemic absorption averaged 30%, which was approximately sevenfold greater than after dosing with the vaginal cream. The higher drug absorption for the ovule may be related to differences in formulation effects on the vaginal membrane. Nevertheless, systemic exposure to clindamycin from the ovule is still considerably lower than from a therapeutic oral dose.


Sujet(s)
Antibactériens/pharmacocinétique , Absorption , Administration par voie vaginale , Adolescent , Adulte , Aire sous la courbe , Clindamycine/sang , Clindamycine/pharmacocinétique , Études croisées , Femelle , Période , Humains , Injections veineuses , Taux de clairance métabolique , Adulte d'âge moyen , Crèmes, mousses et gels vaginaux
18.
Antimicrob Agents Chemother ; 42(11): 3014-7, 1998 Nov.
Article de Anglais | MEDLINE | ID: mdl-9797245

RÉSUMÉ

Clindamycin, which is usually used in combination with pyrimethamine, has been proven effective in the treatment of cerebral toxoplasmosis in human immunodeficiency virus-infected patients. However, it is not known if clindamycin achieves inhibitory concentrations at the site of infection. Also, it has been hypothesized that the activity of clindamycin against Toxoplasma gondii may be due, at least in part, to a metabolite. We evaluated the penetration of clindamycin and its major metabolite, N-demethylclindamycin (NDC), into cerebrospinal fluid (CSF) of AIDS patients undergoing lumbar puncture for diagnostic purposes. A single, 1,200-mg dose of clindamycin was administered as a 45-min intravenous infusion beginning at 1.5 or 2.5 h before CSF sampling. The concentrations of clindamycin in CSF ranged from 0.091 to 0.429 mg/liter at 1.5 h and from 0.120 to 0.283 mg/liter at 2.5 h following the beginning of the infusion. The concentrations of clindamycin in CSF were well above the 50% inhibitory concentration of 0.001 mg/liter and the parasiticidal concentration of 0.006 mg/liter. NDC was undetectable both in plasma and in CSF. Our study provides a pharmacokinetic rationale for the clinical efficacy of clindamycin in the treatment of cerebral toxoplasmosis.


Sujet(s)
Syndrome d'immunodéficience acquise/métabolisme , Clindamycine/métabolisme , Adulte , Barrière hémato-encéphalique , Clindamycine/administration et posologie , Clindamycine/liquide cérébrospinal , Femelle , Humains , Perfusions veineuses , Mâle , Adulte d'âge moyen , Toxoplasmose cérébrale/traitement médicamenteux
19.
Pediatr Infect Dis J ; 17(9): 799-804, 1998 Sep.
Article de Anglais | MEDLINE | ID: mdl-9779765

RÉSUMÉ

BACKGROUND: Cefpodoxime, an oral third generation cephalosporin antibiotic, is used for the treatment of acute upper respiratory tract infection caused by susceptible bacteria in children 5 months to 12 years of age. We report the results of a randomized two-way crossover study designed to characterize the disposition of a single dose (10 mg/kg) of cefpodoxime proxetil oral suspension in children, under fed and fasted conditions. METHODS: Seventeen children (8.4 months to 12.2 years old, seven female) participated in this study. Each subject received a single 10-mg/kg dose of cefpodoxime proxetil oral suspension, after a predose fast and again coadministered with food. Repeated blood samples (n=10) were obtained during 12 h postdose and cefpodoxime was quantified from plasma by high performance liquid chromatography. Plasma concentration vs. time data were curve fit for each subject with a nonlinear weighted least squares algorithm, and pharmacokinetic parameters were determined from the polyexponential estimates. RESULTS: Cefpodoxime disposition was best characterized using a one-compartment open model with first order absorption. The area under the plasma concentration vs. time curve, Cmax and Ke were not significantly different between fed and fasted conditions. However, Tmax was significantly prolonged (fed=2.79+/-1.10 h vs. fasted=1.93+/-0.54 h) and Ka was significantly smaller (fed=0.42+/-0.14 h(-1) vs. fasted=0.81+/-0.72 h(-1)) in the fed state. CONCLUSIONS: Administration of cefpodoxime in the presence of food affected the rate but not the extent of absorption. Cefpodoxime proxetil oral suspension can be administered without regard to meals in children 6 months to 12 years of age.


Sujet(s)
Ceftizoxime/analogues et dérivés , Céphalosporines/pharmacocinétique , Promédicaments/pharmacocinétique , Aire sous la courbe , Ceftizoxime/sang , Ceftizoxime/pharmacocinétique , Céphalosporines/sang , Enfant , Enfant d'âge préscolaire , Études croisées , Consommation alimentaire , Jeûne , Femelle , Humains , Nourrisson , Mâle ,
20.
Phytochemistry ; 49(1): 1-15, 1998 Sep.
Article de Anglais | MEDLINE | ID: mdl-9745764

RÉSUMÉ

The controversies concerning the evolutionary mechanisms of flowering plants continue unabated in spite of the current trends toward the analysis of macromolecular data and of the growing body of distributional micromolecular data. The usual narrative approach to this latter effort is here replaced by a novel technique, quantitative phytochemistry. An evolutionary outline emerges and reveals modulation of antagonisms as the fundamental mechanism of angiosperm evolutionary ecology. Origin or operation of many systems can be rationalized analogously. It is concluded that the impact of opposing features possesses universal relevance.


Sujet(s)
Évolution biologique , Écologie , Magnoliopsida/génétique , Magnoliopsida/classification , Magnoliopsida/métabolisme
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