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1.
bioRxiv ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38659832

RESUMEN

Background: Ps48/45, a Plasmodium gametocyte surface protein, is a promising candidate for malaria transmission-blocking (TB) vaccine. Due to its relevance for a multispecies vaccine, we explored the cross-reactivity and TB activity of a recombinant P. vivax Ps48/45 protein (rPvs48/45) with sera from P. falciparum-exposed African donors. Methods: rPvs48/45 was produced in Chinese hamster ovary cell lines and tested by ELISA for its cross-reactivity with sera from Burkina Faso, Tanzania, Mali, and Nigeria - In addition, BALB/c mice were immunized with the rPvs48/45 protein formulated in Montanide ISA-51 and inoculated with a crude extract of P. falciparum NF-54 gametocytes to evaluate the parasite-boosting effect on rPvs48/45 antibody titers. Specific anti-rPvs48/45 IgG purified from African sera was used to evaluate the ex vivo TB activity on P. falciparum, using standard mosquito membrane feeding assays (SMFA). Results: rPvs48/45 protein showed cross-reactivity with sera of individuals from all four African countries, in proportions ranging from 94% (Tanzania) to 40% (Nigeria). Also, the level of cross-reactive antibodies varied significantly between countries (p<0.0001), with a higher antibody level in Mali and the lowest in Nigeria. In addition, antibody levels were higher in adults (≥ 17 years) than young children (≤ 5 years) in both Mali and Tanzania, with a higher proportion of responders in adults (90%) than in children (61%) (p<0.0001) in Mali, where male (75%) and female (80%) displayed similar antibody responses. Furthermore, immunization of mice with P. falciparum gametocytes boosted anti-Pvs48/45 antibody responses, recognizing P. falciparum gametocytes in indirect immunofluorescence antibody test. Notably, rPvs48/45 affinity-purified African IgG exhibited a TB activity of 61% against P. falciparum in SMFA. Conclusion: African sera (exposed only to P. falciparum) cross-recognized the rPvs48/45 protein. This, together with the functional activity of IgG, warrants further studies for the potential development of a P. vivax and P. falciparum cross-protective TB vaccine.

2.
Sci Rep ; 14(1): 2790, 2024 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-38307966

RESUMEN

Malaria sterile immunity has been reproducibly induced by immunization with Plasmodium radiation-attenuated sporozoites (RAS). Analyses of sera from RAS-immunized individuals allowed the identification of P. falciparum antigens, such as the circumsporozoite protein (CSP), the basis for the RTS, S and R21Matrix-M vaccines. Similar advances in P. vivax (Pv) vaccination have been elusive. We previously reported 42% (5/12) of sterile protection in malaria-unexposed, Duffy-positive (Fy +) volunteers immunized with PvRAS followed by a controlled human malaria infection (CHMI). Using a custom protein microarray displaying 515 Pv antigens, we found a significantly higher reactivity to PvCSP and one hypothetical protein (PVX_089630) in volunteers protected against P. vivax infection. In mock-vaccinated Fy + volunteers, a strong antibody response to CHMI was also observed. Although the Fy- volunteers immunized with non-irradiated Pv-infected mosquitoes (live sporozoites) did not develop malaria after CHMI, they recognized a high number of antigens, indicating the temporary presence of asexual parasites in peripheral blood. Together, our findings contribute to the understanding of the antibody response to P. vivax infection and allow the identification of novel parasite antigens as vaccine candidates.Trial registration: ClinicalTrials.gov number: NCT01082341.


Asunto(s)
Vacunas contra la Malaria , Malaria Falciparum , Malaria Vivax , Malaria , Animales , Humanos , Plasmodium vivax , Esporozoítos , Formación de Anticuerpos , Inmunización , Vacunación , Malaria/prevención & control , Malaria Falciparum/parasitología , Malaria Vivax/parasitología , Plasmodium falciparum
3.
Expert Opin Pharmacother ; 23(7): 759-768, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35379070

RESUMEN

INTRODUCTION: Plasmodium vivax malaria causes significant disease burden worldwide, especially in Latin America, Southeast Asia, and Oceania. P. vivax is characterized by the production of liver hypnozoites that cause clinical relapses upon periodic activation. Primaquine, an 8-aminoquinoline drug, has been the standard of care for decades to treat liver-stage P. vivax malaria; however, it requires long treatment regimens (one to two weeks) that lead to poor adherence and thus clinical relapses. Tafenoquine (TFQ), a newly available and efficacious single-dose 8-aminoquinoline, aims to address this challenge. Safe administration is possible when paired with the use of glucose-6-phosphate dehydrogenase (G6PD) diagnostics to prevent 8-aminoquinoline-induced hemolysis in patients with underlying G6PD deficiency (G6PDd). AREAS COVERED: In this review, the authors present the recent literature regarding the pharmacology, efficacy, safety, and tolerability of TFQ and highlight regional differences in these areas. The authors also discuss the potential for TFQ, complemented with primaquine PQ and effective screening for G6PDd, to improve P. vivax clinical management and facilitate targeted mass drug administration in communities to decrease transmission. EXPERT OPINION: Clinical studies show therapeutic efficacy of TFQ as well as a good performance in terms of safety and tolerability. Additional research regarding the effectiveness and safety TFQ in malaria elimination strategies, such as targeted or mass drug administration, are needed.


Asunto(s)
Antimaláricos , Malaria Vivax , Aminoquinolinas , Antimaláricos/efectos adversos , Humanos , Malaria Vivax/tratamiento farmacológico , Malaria Vivax/prevención & control , Plasmodium vivax , Primaquina/efectos adversos , Recurrencia
4.
Nat Commun ; 13(1): 1603, 2022 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-35338131

RESUMEN

A randomized, double-blind, controlled vaccine clinical trial was conducted to assess, as the primary outcome, the safety and protective efficacy of the Plasmodium vivax circumsporozoite (CS) protein in healthy malaria-naïve (phase IIa) and semi-immune (phase IIb) volunteers. Participants (n = 35) were randomly selected from a larger group (n = 121) and further divided into naïve (n = 17) and semi-immune (n = 18) groups and were immunized at months 0, 2, and 6 with PvCS formulated in Montanide ISA-51 adjuvant or placebo (adjuvant alone). Specific antibodies and IFN-γ responses to PvCS were determined as secondary outcome; all experimental volunteers developed specific IgG and IFN-γ. Three months after the last immunization, all participants were subjected to controlled human malaria infection. All naive controls became infected and drastic parasitemia reduction, including sterile protection, developed in several experimental volunteers in phase IIa (6/11) (54%, 95% CI 0.25-0.84) and phase IIb (7/11) (64%, 95% CI 0.35-0.92). However, no difference in parasitemia was observed between the phase IIb experimental and control subgroups. In conclusion, this study demonstrates significant protection in both naïve and semi-immune volunteers, encouraging further PvCS vaccine clinical development. Trial registration number NCT02083068. This trial was funded by Colciencias (grant 529-2009), NHLBI (grant RHL086488 A), and MVDC/CIV Foundation (grant 2014-1206).


Asunto(s)
Vacunas contra la Malaria , Malaria , Anticuerpos Antiprotozoarios , Humanos , Aceite Mineral , Parasitemia , Plasmodium vivax , Proteínas Protozoarias , Vacunas Sintéticas
5.
Malar J ; 19(1): 113, 2020 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-32183833

RESUMEN

BACKGROUND: New strategies are needed to reduce the incidence of malaria, and promising approaches include the development of vaccines and monoclonal antibodies (mAbs) that target the circumsporozoite protein (CSP). To select the best candidates and speed development, it is essential to standardize preclinical assays to measure the potency of such interventions in animal models. METHODS: Two assay configurations were studied using transgenic Plasmodium berghei expressing Plasmodium falciparum full-length circumsporozoite protein. The assays measured (1) reduction in parasite infection of the liver (liver burden) following an intravenous (i.v) administration of sporozoites and (2) protection from parasitaemia following mosquito bite challenge. Two human CSP mAbs, AB311 and AB317, were compared for their ability to inhibit infection. Multiple independent experiments were conducted to define assay variability and resultant impact on the ability to discriminate differences in mAb functional activity. RESULTS: Overall, the assays produced highly consistent results in that all individual experiments showed greater functional activity for AB317 compared to AB311 as calculated by the dose required for 50% inhibition (ID50) as well as the serum concentration required for 50% inhibition (IC50). The data were then used to model experimental designs with adequate statistical power to rigorously screen, compare, and rank order novel anti-CSP mAbs. CONCLUSION: The results indicate that in vivo assays described here can provide reliable information for comparing the functional activity of mAbs. The results also provide guidance regarding selection of the appropriate experimental design, dose selection, and group sizes.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Parasitemia/prevención & control , Plasmodium falciparum/inmunología , Proteínas Protozoarias/inmunología , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Antiprotozoarios/sangre , Modelos Animales de Enfermedad , Femenino , Concentración 50 Inhibidora , Hígado/parasitología , Malaria Falciparum/inmunología , Malaria Falciparum/terapia , Ratones , Ratones Endogámicos C57BL , Organismos Modificados Genéticamente , Carga de Parásitos , Plasmodium berghei/genética , Plasmodium falciparum/genética , Proteínas Protozoarias/genética
6.
Malar J ; 18(1): 426, 2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-31849326

RESUMEN

BACKGROUND: The circumsporozoite protein (CSP) of Plasmodium is a key surface antigen that induces antibodies and T-cells, conferring immune protection in animal models and humans. However, much of the work on CSP and immunity has been developed based on studies using rodent or non-human primate CSP antigens, which may not be entirely translatable to CSP expressed by human malaria parasites, especially considering the host specificity of the different species. METHODS: Using a genetically engineered strain of Plasmodium berghei that expresses luciferase, GFP and the Plasmodium falciparum orthologue of CSP, the effect of laboratory preparation, mosquito treatment and mouse factors on sporozoite infectivity was assessed using an in vivo bioluminescence assay on mice. This assay was compared with a PCR-based protection assay using an already described monoclonal antibody that can provide sterile protection against sporozoite challenge. RESULTS: Bioluminescence assay demonstrated similar detection levels of the quantity and kinetics of liver-stage infection, compared to PCR-based detection. This assay was used to evaluate treatment of sporozoite and delivery method on mouse infectivity, as well as the effects of age, sex and strain of mice. Finally, this assay was used to test the protective capacity of monoclonal antibody AB317; results strongly recapitulate the findings of previous work on this antibody. CONCLUSIONS: The PbGFP-Luc line and in vivo bioluminescence imaging provide highly sensitive read-outs of liver-stage infection in mice, and this method can be useful to reliably evaluate potency of pre-erythrocytic interventions.


Asunto(s)
Malaria/inmunología , Plasmodium berghei/fisiología , Animales , Anopheles/parasitología , Femenino , Ensayos Analíticos de Alto Rendimiento , Hígado/parasitología , Luciferasas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Microorganismos Modificados Genéticamente/genética , Microorganismos Modificados Genéticamente/fisiología , Plasmodium berghei/genética , Plasmodium falciparum/genética , Proteínas Protozoarias/metabolismo , Esporozoítos/crecimiento & desarrollo
8.
Malar J ; 16(1): 273, 2017 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-28676055

RESUMEN

In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an important public health concern in the region. Most malaria cases in South America come from Amazon rain forest areas in northern countries, where more than half of malaria is caused by Plasmodium vivax, while Plasmodium falciparum malaria incidence has decreased in recent years. This review discusses current malaria data, policies and challenges in four South American Amazon countries: Brazil, Colombia, Peru and the Bolivarian Republic of Venezuela. Challenges to continuing efforts to further decrease malaria incidence in this region include: a significant increase in malaria cases in recent years in Venezuela, evidence of submicroscopic and asymptomatic infections, peri-urban malaria, gold mining-related malaria, malaria in pregnancy, glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine use, and possible under-detection of Plasmodium malariae. Some of these challenges underscore the need to implement appropriate tools and procedures in specific regions, such as a field-compatible molecular malaria test, a P. malariae-specific test, malaria diagnosis and appropriate treatment as part of regular antenatal care visits, G6PD test before primaquine administration for P. vivax cases (with weekly primaquine regimen for G6PD deficient individuals), single low dose of primaquine for P. falciparum malaria in Colombia, and national and regional efforts to contain malaria spread in Venezuela urgently needed especially in mining areas. Joint efforts and commitment towards malaria control and elimination should be strategized based on examples of successful regional malaria fighting initiatives, such as PAMAFRO and RAVREDA/AMI.


Asunto(s)
Erradicación de la Enfermedad/tendencias , Política de Salud/legislación & jurisprudencia , Malaria/prevención & control , Plasmodium , Animales , Antimaláricos/uso terapéutico , Brasil/epidemiología , Colombia/epidemiología , Humanos , Incidencia , Malaria/tratamiento farmacológico , Malaria/epidemiología , Malaria/parasitología , Perú/epidemiología , Plasmodium/aislamiento & purificación , Plasmodium/fisiología , Vigilancia de la Población , Prevalencia , Venezuela/epidemiología
10.
J Hazard Mater ; 292: 34-43, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25796038

RESUMEN

The continuous ozonation of the antibiotic ofloxacin (OFX) has been performed using a synthetic water matrix and in a sewage treatment plant (STP) effluent. The aim was to study the effect of the water matrix on the ozonation with particular emphasis on the aquatic toxicity of treated water. OFX was completely removed in both water matrices, although the amount of ozone consumed for its depletion was strongly matrix-dependent. The extent of mineralization was limited and a number of intermediate transformation products (TPs) appeared, twelve of which could be identified. OFX reaction pathway includes the degradation of piperazinyl and quinolone moieties. The further oxidation of TPs gave rise to the formation and accumulation of carboxylic acids, aldehydes, nitrogen-containing organic compounds and inorganic ions. Aquatic toxicity of treated mixtures was assessed using four standard species: the bacteria Vibrio fischeri and Pseudomonas putida as target organisms and the algae Pseudokirchneriella subcapitata and the protozoan Tetrahymena thermophila as non-target organisms. OFX was toxic for the bacteria and the microalgae at the spiked concentration in untreated water. However, the continuous ozonation at the upper operational limit removed its toxic effects. T. thermophila was not affected by OFX, but was sensitive to STP effluent.


Asunto(s)
Antibacterianos/química , Ofloxacino/química , Ozono/química , Contaminantes Químicos del Agua/química
11.
Talanta ; 134: 415-424, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25618688

RESUMEN

In this study, a very sensitive method was validated to determine pesticides residues in fruit jams using micro flow liquid chromatography-tandem mass spectrometry (µLC-MS/MS). A slurry of the fruit jams and water was prepared to yield homogeneous samples. Because of the high sensitivity achieved with the µLC-MS/MS equipment and to minimize matrix effects, the QuEChERS extracts were diluted 30-fold before the analysis. The validation was performed analyzing spiked samples at 9 and 45 µg kg(-1) (n=5). The method met validation criteria of 70-120% recovery and RSD≤20% for 92% of the 107 pesticides evaluated. The reporting limit (RL) was 9 and 45 µg kg(-1) for respectively 66% and 26% of the analytes, 5% of the compounds did not fulfill the requirements for validation and 3% were not detected at the studied concentrations. The validated method was applied to the analysis of 51 different fruit jam samples from Brazil and Spain and pesticide residues were detected in 41 samples, 26 of which contained at least one pesticide at concentration >10 µg kg(-1).


Asunto(s)
Contaminación de Alimentos/análisis , Alimentos en Conserva/análisis , Frutas , Residuos de Plaguicidas/análisis , Cromatografía Liquida/métodos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos
12.
Sci Total Environ ; 472: 273-81, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24291627

RESUMEN

In the present work, the sorption of pharmaceutical and personal care products (PPCPs) (acetaminophen, atenolol, carbamazepine, caffeine, naproxen and sulphamethoxazole) onto the natural organic matter (NOM) and the inorganic surfaces of a natural sandy loam sediment was quantified separately. The quantification was based on the PPCP charge, their degree of ionisation, their octanol-water partitioning coefficient (KOW) and the sediment organic carbon fraction (ƒOC). PPCP desorption from the sediment was examined under conditions of infiltrating water containing a high concentration of inorganic ions (mimicking infiltrating reclaimed water), and a low concentration (and smaller diversity) of inorganic ions (mimicking rainwater infiltration). Batch tests were performed using a sediment/water ratio of 1:4 and a PPCP initial concentration ranging from 1 to 100 µg L(-1). The results showed the type and degree of PPCP ionisation to strongly influence the sorption of these compounds onto the sediment. The sorption of cationic species onto the sediment was higher than that of anionic species and mostly reversible; the sorption of neutral species was negligible. The anionic species sorbed less onto the sediment, but also desorbed less easily. More than 70% of the total sorption was due to interaction with mineral surfaces. This holds especially true for cationic species (atenolol and caffeine) which sorption was enhanced by the negative surface charge of the sediment. The presence of inorganic ions had no impact on the desorption of the PPCPs from the sediment. According to the calculated percentages of removal, the mobility followed the order: carbamazepine>acetaminophen>naproxen>atenolol>sulfamethoxazole>caffeine.


Asunto(s)
Cosméticos/análisis , Sedimentos Geológicos/química , Preparaciones Farmacéuticas/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Adsorción , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Eliminación de Residuos Líquidos
13.
Artículo en Inglés | MEDLINE | ID: mdl-25834763

RESUMEN

OBJECTIVE: To evaluate the impact of the implementation of a guideline for the management of personality disorders on reducing the frequency of use of mechanical restraints in a psychiatric inpatient unit. METHOD: This retrospective study was conducted in a psychiatric inpatient unit with 42 beds, which serves an urban area of 330,000 inhabitants. The sample consisted of all patients with a clinical diagnosis of personality disorder (DSM-IV-TR criteria) who were admitted to the unit from January 2010 to December 2010 and from January 2011 to December 2011 (ie, before and after, respectively, the implementation of the guideline). The guideline focused on cluster B disorders and follows a psychodynamic perspective. RESULTS: Restraint use was reduced from 38 of 87 patients with personality disorders (43.7%) to 3 of 112 (2.7%), for a relative risk of 0.06 (95% CI, 0.02-0.19) and an absolute risk reduction of 41% (95% CI, 29.9%-51.6%). The risk of being discharged against medical advice increased after the intervention, with a relative risk of 1.84 (95% CI, 0.96-3.51). Restraint use in patients with other diagnoses was also reduced to a similar extent. CONCLUSIONS: The use of mechanical restraints was dramatically reduced after the implementation of a clinical practice guideline on personality disorders, suggesting that these coercive measures might be decreased in psychiatric inpatient units.

14.
Environ Sci Pollut Res Int ; 20(8): 5813-26, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23475443

RESUMEN

In order to evaluate the water quality at the surface/groundwater interface (hyporheic zone), the pattern of microcrustacean assemblages in response to environmental stress caused by urban industrial contamination was studied in the Jarama River basin (central Spain) during high water discharges (March and April 2011). The clustering of biological variables and the concentration of urban contaminants in hyporheic waters showed that pristine hyporheic waters have moderate species diversity (two to seven species) and dominance of k strategist stygobites, whereas excessively contaminated sites are devoid by crustaceans. An intermediate level of disturbance in hyporheic waters is associated with a peak of species taxonomic diversity (four to nine species) and proliferation of r strategist more tolerant species. Typical species found in hyporheic zone, e.g., Paracyclops imminutus (Copepoda, Cyclopoida), Cryptocandona vavrai (Ostracoda) and Herpetocypris chevreuxi (Ostracoda), were good indicators of high concentrations of Cr, Mn, Ni, Cd, Pb and VOCs; whereas the stygobites do not show any significant correlation. The effectiveness of hyporheic crustaceans as efficient bioindicators for assessing the current ecological status of river ecosystems is emphasised.


Asunto(s)
Crustáceos/clasificación , Contaminantes Químicos del Agua/análisis , Animales , Biodiversidad , Ciudades , Monitoreo del Ambiente , Agua Subterránea , Metales Pesados/análisis , Nitratos/análisis , Densidad de Población , Compuestos de Amonio Cuaternario/análisis , Ríos , España , Compuestos Orgánicos Volátiles/análisis , Eliminación de Residuos Líquidos
15.
Anal Bioanal Chem ; 404(6-7): 1993-2006, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22850896

RESUMEN

A new analytical method using stir-bar-sorptive extraction (SBSE) followed by liquid desorption (LD) and gas chromatography with triple-quadrupole mass spectrometric detection (GC-QqQ-MS-MS) has been used for quantitative determination of 25 chlorinated endocrine-disrupting compounds (EDCs) in river water and wastewater. The experimental conditions affecting the SBSE-LD performance were studied and are discussed in detail. Results from systematic assay revealed that a 100-mL water sample, stir bars coated with 47 µL PDMS, an extraction time of 14 h (at 900 rpm), 5 % MeOH as modifier and 10 % NaCl resulted in the best analytical recovery of all the target compounds studied. Use of 1:1 ACN-MeOH as back-extraction solvent and two successive sonication steps, each for 5 min, resulted in the best performance for monitoring EDCs in water matrices. The method detection limits for most of the target compounds were very good- ≤ 2 ng L(-1) and ≤10 ng L(-1) for river water and wastewater effluents respectively. Experimental recovery for all the compounds was >70 %, with the exception of simazine for which recovery from the matrix was 65 %. Signal enhancement observed for a few of the compounds in wastewater effluents was managed by use of matrix-matched standards and different injection liners. The method was successfully used for analysis of river water samples from Henares River (Spain) and wastewater effluent samples from wastewater-treatment plants (WWTP). Eleven of the 25 compounds studied were detected in both river water and wastewater effluents. Terbutylazine and methoxychlor were detected in almost all the river water and effluent samples; amounts varied between 37-58.5 ng L(-1) and 15.2-46.8 ng L(-1), respectively. This method was shown enable reliable, effective, and sensitive monitoring of chlorinated EDCs at nanogram levels in surface water and wastewater effluent.


Asunto(s)
Disruptores Endocrinos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Clorados/análisis , Ríos/química , Extracción en Fase Sólida/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Disruptores Endocrinos/aislamiento & purificación , Hidrocarburos Clorados/aislamiento & purificación , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/aislamiento & purificación
16.
Water Res ; 46(14): 4435-47, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22709983

RESUMEN

Synthetic musks have been reported in wastewaters at concentrations as high as tens of micrograms per litre. The two most significant polycyclic musk fragrance compounds are 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyran (HHCB, trade name galaxolide®) and 7-acetyl-1,1,3,4,4,6-hexamethyltetrahydronaphthalene (AHTN, trade name tonalide®). We report the result of several irradiation and advanced oxidation processes carried out on samples of the effluent of a wastewater treatment plant located in Alcalá de Henares, Madrid. Wastewater samples were pre-ozonated and spiked with 500 ng/L of tonalide or galaxolide in order to obtain final concentrations in the same order as the raw effluent. The treatments assayed were ozonation with and without the addition of hydrogen peroxide (O3, O3/H2O2), ultraviolet (254 nm low pressure mercury lamp) and xenon-arc visible light irradiation alone and in combination with ozone (UV, O3/UV, Xe, O3/Xe) and visible light photocatalytic oxidation using a Ce-doped titanium dioxide photocatalyst performed under continuous oxygen or ozone gas bubbling (O2/Xe/Ce-TiO2, O3/Xe/Ce-TiO2). In all cases, samples taken at different contact times up to 15 min were analyzed. An analytical method based on stir bar sorptive extraction (SBSE), followed by comprehensive two-dimensional gas chromatography (SBSE-GC × GC-TOF-MS), was used for the automatic searching and evaluation of the synthetic musks and other nonpolar or semipolar contaminants in the wastewater samples. In all cases tonalide was more easily removed than galaxolide. The best results for the latter (more than 75% removal after 5 min on stream) were obtained from ozonation (O3) and visible light photocatalytic ozonation (O3/Xe/Ce-TiO2). A significant removal of both pollutants (∼60% after 15 min) was also obtained during visible light photocatalysis (O2/Xe/Ce-TiO2). UV radiation was able to deplete tonalide (+90%) after 15 min but only reduced the concentration of galaxolide to about half of its initial concentration. The toxicity of treated samples decreased for O3/UV and O3/Ce-TiO2, but increased during irradiation processes UV, Xe and Xe/Ce-TiO2. Ozone treatments tend to decrease toxicity up to a certain dosage, from which point the presence of toxic transformation products has adverse effects on aquatic microorganisms.


Asunto(s)
Benzopiranos/aislamiento & purificación , Procesos Fotoquímicos , Tetrahidronaftalenos/aislamiento & purificación , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Animales , Benzopiranos/química , Benzopiranos/toxicidad , Células Inmovilizadas/efectos de los fármacos , Daphnia/citología , Daphnia/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Radical Hidroxilo/química , Oxidación-Reducción/efectos de los fármacos , Oxidación-Reducción/efectos de la radiación , Ozono/química , Procesos Fotoquímicos/efectos de los fármacos , Procesos Fotoquímicos/efectos de la radiación , Tetrahidronaftalenos/química , Tetrahidronaftalenos/toxicidad , Pruebas de Toxicidad , Rayos Ultravioleta , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad
17.
Sci Total Environ ; 420: 134-45, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22326139

RESUMEN

This study aims to assess the occurrence, fate and temporal and spatial distribution of anthropogenic contaminants in a river subjected to different pressures (industrial, agricultural, wastewater discharges). For this purpose, the Henares River basin (central Spain) can be considered a representative basin within a continental Mediterranean climate. As the studied river runs through several residential, industrial and agricultural areas, it would be expected that the chemical water quality is modified along its course. Thereby the selection of sampling points and timing of sample collection are critical factors in the monitoring of a river basin. In this study, six different monitoring campaigns were performed in 2010 and contaminants were measured at the effluent point of the main wastewater treatment plant (WWTP) in the river basin and at five different points upstream and downstream from the WWTP emission point. The target compounds evaluated were personal care products (PCPs), polycyclic aromatic hydrocarbons (PAHs) and pesticides. Results show that the river is clearly influenced by wastewater discharges and also by its proximity to agricultural areas. The contaminants detected at higher concentrations were the PCPs. The spatial distribution of the contaminants indicates that the studied contaminants persist along the river. In the time period studied no great seasonal variations of PCPs at the river collection points were observed. In contrast, a temporal trend of pesticides and PAHs was observed. Besides the target compounds, other new contaminants were identified and evaluated in the water samples, some of them being investigated for the first time in the aquatic environment. The behaviour of three important transformation products was also evaluated: 9,10-anthracenodione, galaxolide-lactone and 4-amino-musk xylene. These were found at higher concentrations than their parent compounds, indicating the significance of including the study of transformation products in the monitoring programmes.


Asunto(s)
Ríos/química , Contaminantes del Agua/análisis , Contaminación del Agua/análisis , Calidad del Agua , Agricultura , España , Factores de Tiempo , Movimientos del Agua , Contaminantes del Agua/química
18.
Anal Chem ; 83(7): 2638-47, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21388147

RESUMEN

A new analytical method based on stir bar sorptive extraction (SBSE), followed by comprehensive two-dimensional gas chromatography (GCxGC-TOF-MS), has been developed for the automatic searching and evaluation of nonpolar or semipolar contaminants in wastewater and river water. The target compounds selected were 13 personal care products (PCPs), 15 polycyclic aromatic hydrocarbons (PAHs) and 27 pesticides. Excellent results have been obtained in terms of separation efficiency and also in terms of compound identification. Exceptional method detection limits were achieved applying the optimized method, at or below 1 ng/L for most of the compounds in real samples. The reliable confirmation of analyte identity was possible at this low concentration level, even for typically troublesome compounds such as the PAHs. The other validation parameters were good. In addition to obtaining analytical information such as identification and quantification of target analytes, it is also possible to screen for nontarget compounds or unknowns. New contaminants have been identified in the wastewater effluents and river water samples, such as cholesterol and its degradation products, pharmaceuticals, industrial products, other pesticides, and PCPs. The multidimensional information generated by the instrument can also be used by the researchers for contrasting samples and identifying, much more easily, the major differences between samples. We have used this feature to propose studies of comparison between the fingerprinting of different water samples, such as the contamination variation along a river affected by the discharge of urban wastewaters and also the contamination variation over a period of time in the effluent. Results show that the most frequently detected contaminants (and the contaminants detected at higher concentrations) were the PCPs. The musk fragrances galaxolide and tonalid were the most concentrated compounds in the samples. The pesticides and PAHs were present at much lower concentration than PCPs.


Asunto(s)
Fraccionamiento Químico/métodos , Cromatografía de Gases/métodos , Espectrometría de Masas/métodos , Ríos/química , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Automatización , Compuestos Orgánicos/análisis , Compuestos Orgánicos/aislamiento & purificación , Factores de Tiempo
19.
Anal Chim Acta ; 665(1): 47-54, 2010 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-20381689

RESUMEN

This paper describes the development of an analytical procedure to determine malachite green (MG) residues in salmon samples using molecularly imprinted polymers (MIPs) as the extraction and clean-up material, followed by liquid chromatography-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS). MG and two structurally related compounds, crystal violet (CV) and brilliant green (BG) were employed for the selectivity test. The imprinted polymers exhibited high binding affinity for MG, while CV and BG showed less binding capacity: 47% and 34%, respectively. The recovery values of MG in salmon samples fortified with leucomalachite green (LMG) were determined by measuring the amount of MG in the sample, after carrying out the oxidation reaction with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), which converts the LMG back into chromic-form. The average recovery of MG in spiked salmon muscle over the concentration range 1-100 ng g(-1) was 98% with a relative standard deviation value (R.S.D.) below 12%. The method detection limits (MDLs) obtained for MG, CV, BG and their leuco-metabolites were in the range of 3-20 ng kg(-1) (ppt).


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Colorantes de Rosanilina/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Animales , Violeta de Genciana/análisis , Violeta de Genciana/aislamiento & purificación , Impresión Molecular , Compuestos de Amonio Cuaternario/análisis , Compuestos de Amonio Cuaternario/aislamiento & purificación , Colorantes de Rosanilina/aislamiento & purificación , Salmón/metabolismo , Extracción en Fase Sólida
20.
Rev. cientif. cienc. med ; 12(2): 23-25, 2009. ilus
Artículo en Español | LILACS | ID: lil-737957

RESUMEN

La Metformina comenzó a utilizarse en el tratamiento de la diabetes mellitus tipo 2 en 1957 en Europa y en 1995 en EE. UU. Actualmente es el antihiperglucemiante oral mas frecuentemente recetado en todo el mundo. En 1998 el United Kingdom Prospective Diabetes Study, demostró los efectos antiaterogénicos de metformina y más tarde se descubrió que mejoraba muchos componentes del síndrome de resistencia a insulina (síndrome metabólico). El US Diabetes Prevention Program, demostró el potencial de metformina en la prevención de la diabetes. Su eficacia, seguridad, múltiples beneficios cardiovasculares y metabólicos, y la capacidad de poder utilizarse en combinación con todos los demás fármacos antidiabéticos, incluida la insulina, han convertido a metformina en el fármaco oral de primera línea para el tratamiento de los pacientes con diabetes mellitus tipo 2. En los últimos años ha surgido evidencia para indicar metformina en pacientes no diabéticos, principalmente aquellos con síndrome metabólico, intolerantes a la glucosa y mujeres que buscan un embarazo y padecen del síndrome de ovario poliquístico. Además podría mejorar las características clínicas de los estados resistentes a insulina, aparte de la diabetes tipo 2. Su papel en la prevención del cáncer podría ser otro de los desarrollos de metformina en el futuro. El objetivo de esta revisión es actualizar sobre las nuevas directrices de este fármaco.


Metformin began to be used in the treatment of type 2 diabetes mellitus in 1957 in Europe and 1995 in EE. UU. He is currently the most frequently prescribed oral anti-hyperglycaemic worldwide. In 1998, the United Kingdom Prospective Diabetes Study demonstrated antiatherogenic effects of metformin and later discovered that improved many components of insulin resistance syndrome (metabolic syndrome). The U.S. Diabetes Prevention Program demonstrated the potential of metformin in preventing diabetes. Its efficacy, safety, multiple cardiovascular and metabolic benefits, and the ability to be used in combination with all other antidiabetic agents, including insulin, metformin has made in the first line oral drug for the treatment of patients with diabetes mellitus type 2. In recent years evidence has surfaced to indicate metformin in nondiabetic patients, primarily those with metabolic syndrome, glucose intolerant and women seeking a pregnancy and suffer from polycystic ovary syndrome. It could also improve the clinical characteristics of insulin resistant states, apart from type 2 diabetes. Its role in cancer prevention could be another of the developments of metformin in the future. The objective of this review is to update on the new guidelines of the drug.

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