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1.
Environ Geochem Health ; 45(6): 3155-3169, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36166169

RESUMO

In this study, the concentration of six metal(loid)s was examined in the fish Oreochromis aureus collected from El Comedero dam during a massive mortality event induced by a mine tailing spill. A major spill (~ 300,000 m3) of waste was released into the San Lorenzo River System following a rupture in the tailing dam of a mining plant in NW Mexico; consequently, the discharged material flowed into El Comedero dam. The accumulation of metal(oid)s in the tissues of O. aureus showed higher levels in the liver than in the guts and muscle. Concentrations in the liver were high (As, 1.1-1063; Cd, 8.9-392; Cu, 372-59,129; Hg, 0.46-19.79; Se, 8.7-748; and Zn, 116-820 µg g-1), revealing that these fish were exposed to high concentrations of these elements. The mortality of fish could have resulted from the combined effect of the six analyzed metal(loid)s, as well as other residues present in mine tailings.


Assuntos
Metaloides , Metais Pesados , Tilápia , Animais , Metaloides/toxicidade , Metaloides/análise , Monitoramento Ambiental , Metais/toxicidade , Metais/análise , Fígado , Metais Pesados/análise
2.
Environ Geochem Health ; 45(7): 4533-4548, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36853523

RESUMO

The failure of a tailings dam occurred in January 2013 at the Santa María de Otáez mining region (Mexico) released a spill (~ 300,000 m3) on Los Remedios River, which was transported through the San Lorenzo River, and finally to El Comedero (EC) dam. The concentrations of metal(loid)s in the muscle, liver, gills, and guts of three fish species (Cyprinus carpio, Oreochromis aureus, Micropterus salmoides) collected from EC dam were examined twenty months later to assess the performance of the cleaning operations. The bioaccumulation patterns of the metal(loid)s in the tissues were different in the three fish species. Tilapia had the highest Cd (11.23 ± 8.53 µg g-1) and Cu (871 ± 1261 µg g-1) concentrations in the liver, as well as As concentration (83.6 ± 61.7 µg g-1) in the gut, while the highest Zn concentration (745 ± 356 µg g-1) was measured in the gills of the carp. Such variability can be caused by the variant bioavailability of the metal(loid)s and by the feeding habits of each species; and also by the fact that some metals are essential and better regulated by organisms than other non-essential. Compared to a study of tilapia carried out 90 days after mine spill, a decrease was evident in the liver for As, Cd, Cu, and Zn by 129, 5, 10, and 1.7 times, respectively. This revealed that cleaning operations were more efficient for As. The target hazard quotient and the hazard index were < 1, which indicates there will be no risk of consuming muscle in moderated rations of the three fish species.


Assuntos
Carpas , Metais Pesados , Poluentes Químicos da Água , Animais , Metais Pesados/análise , Cádmio , Bioacumulação , Monitoramento Ambiental , Zinco/análise , Poluentes Químicos da Água/análise
3.
Bioprocess Biosyst Eng ; 44(7): 1525-1538, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33860372

RESUMO

A biofertilizer of Azospirillum brasilense was produced in solid-state culture (SSC) from laboratory to pilot scale. Similar operation conditions (continuous aeration and mild intermittent mixing) and two dimensionless numbers with similar L/D ratio and a similar working volume were applied to reach a scale-up factor of 75. An innovative bioreactor with rotating helical ribbons (15 kg wet matter) was used at pilot scale. A mathematical model was proposed and validated to evaluate the respirometry trends at laboratory and pilot scale exhibiting similar behavior. The cell viability was (1.3 ± 0.4) × 109 and (1.3 ± 0.3) × 109 colony-forming units per gram of initial dry mass at laboratory and pilot scale, at 36 and 43 h, respectively. A. brasilense maintains its viability twelve months of storage at 4 and 30 °C. This is the first report of A. brasilense being cultivated in SSC under controlled conditions. SSC processes involving unicellular microorganisms with tolerance to agitation are a promising technology to produce biofertilizers.


Assuntos
Azospirillum brasilense/metabolismo , Reatores Biológicos , Biotecnologia/métodos , Glicerol/química , Microbiologia Industrial/métodos , Fermentação , Fertilizantes , Concentração de Íons de Hidrogênio , Cinética , Laboratórios , Microscopia Eletrônica de Varredura , Modelos Teóricos , Consumo de Oxigênio , Células-Tronco
4.
J Insect Sci ; 17(4)2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28973492

RESUMO

Factors limiting distribution range for most species are generally unknown regardless of whether they are native or invasive. We studied factors that could enable or restrict the distribution of two cosmopolitan invasive leafminer fly species, Liriomyza huidobrensis (Blanchard) and Liriomyza sativae (Blanchard) in their native niche. In order to test which ecological and environmental factors affect leafminer distribution we conducted thermal tolerance assays, sampled along elevation gradients and modeled species distribution. Findings from the field and rearing chambers showed a physiological restriction due to high temperatures for L. huidobrensis at 28-29 °C, above which adult emergence is compromised. We also found that maximum temperatures below 22 °C, typical of tropical highlands, favored L. huidobrensis. L. sativae was found across a wider temperature range (i.e., from 21 to 36 °C) in Guatemala. Our finding of a physiological threshold in temperature for L. huidobrensis may enable us to predict its invasive risk when combined with the environmental conditions at horticultural ports of entry and the global agricultural landscape. Further, it strengthens our predictions on shifts in distribution of the leafminer fly under future climate. We also found a temperature mediated competitive exclusion interaction between the two herbivore species, where L. sativae occurred at temperatures < 22 °C only in the absence of L. huidobrensis. We show that parasitoids had a negative effect on the leafminer flies, which varied with host plant. Finally, we show the importance of taking a multiaspect approach when investigating what limits distribution and invasiveness of a species.


Assuntos
Dípteros , Ecossistema , Temperatura , Altitude , Animais , Clima , Produtos Agrícolas , Guatemala
5.
Environ Monit Assess ; 189(8): 395, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28710691

RESUMO

This study evaluated the suitability of 21 inland waters (16 well waters and 5 surface waters) from Northwest Mexico via short- (48 h) and medium-term (28 days) tests using postlarvae (PL18) of Litopenaeus vannamei. In the short test, survival was assessed at 48 h after shrimp were placed in groups of 10 postlarvae into 2-L containers of inland water, to which they had been previously acclimated. The second, medium-term test consisted of four replicates with 10 postlarvae, and each group was placed in 15-L containers with the treatment water. Weights (initial and final) and survival were evaluated weekly for 28 days. In those waters for which the short test was positive and the medium-term test was negative and which also had a deficiency of potassium and/or magnesium, a third test was conducted. These last waters were supplemented with salts, and the shrimp survival and weights (initial and final) were recorded for 28 days. The water samples from San Jose, Mochicahui, Sinaloa River, Caimanero inner Lagoon, La Pipima, Campo Santa Fe, Escopama, and Fitmar had >60% survival in the short test. The Caimanero inner Lagoon water had the highest survival (87.5 ± 9.6%) and final mean weight (201.3 ± 86.2 mg). In the third test, it was found that shrimp in the water from La Pipima, Campo Santa Fe, and Fitmar exhibited 100% survival for 2 weeks. Finally, in this work, a decision tree to evaluate the suitability of low-salinity water for shrimp farming was proposed, which can be applied in other regions.


Assuntos
Monitoramento Ambiental , Penaeidae/fisiologia , Frutos do Mar , Água/química , Animais , Aquicultura , Suplementos Nutricionais , Magnésio/metabolismo , México , Penaeidae/crescimento & desenvolvimento , Potássio/metabolismo , Sais/metabolismo , Qualidade da Água
6.
Public Health ; 137: 124-30, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27003670

RESUMO

OBJECTIVES: This study aims to examine current hookah users' perceptions, attitudes, and normative beliefs regarding hookah smoking to further elucidate the rise in hookah smoking prevalence among young adults (aged 18-24 years) and reveal why hookah smoking is perceived as less harmful than other forms of tobacco consumption. STUDY DESIGN: Qualitative. METHODS: Data from six focus group interviews with hookah smokers aged between 18 and 24 years were analyzed using a grounded theory approach. Focus groups were evenly split between frequent and infrequent hookah users, and were predominantly composed of college students, with two groups of hookah users consisting of 18-24 year olds of non-student status. RESULTS: Hookah users shared a much larger set of positive hookah smoking behavioral beliefs as opposed to negative behavioral beliefs. Generational traits served as the overarching commonality among the behavior performance initiation determinants observed. The most notable generational trends observed were within the cultural category, which included the following millennial characteristics: autonomy, personalization, novelty appeal, convenience, globally oriented, entertainment, collaboration, health conscious, and valuing their social network. CONCLUSIONS: Millennial hookah users revealed mindfulness regarding both potential negative and positive reasons stemming from continued hookah use; however, behavioral beliefs were primarily fixated on the perception that hookah smoking was a healthier alternative to cigarette smoking. Future implications for this study's findings include generating more positive ways to express these traits for young adults; policy implications include raising hookah bar age limits, implementing indoor smoking restrictions, and limiting the ease of accessibility for purchasing hookah supplies.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Fumar/psicologia , Adolescente , Feminino , Florida/epidemiologia , Grupos Focais , Humanos , Masculino , Prevalência , Pesquisa Qualitativa , Medição de Risco , Fumar/epidemiologia , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Universidades , Adulto Jovem
7.
Int J Food Microbiol ; 404: 110320, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37490784

RESUMO

The Gram-positive bacteria lactic acid bacteria (LAB) are used in the food industry but are also known for inhibiting certain food spoilage microorganisms, especially fungi. Sources of nitrogen (N) for culture media are generally organic and expensive. Many attempts have been made to formulate economical culture media with alternative N sources obtained from agricultural and industrial byproducts. This study describes the design and optimization of an inexpensive culture medium for Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) MZ809351 strain B31. The culture medium was optimized using statistical experimental designs to identify the factors with the most significant effects on biomass concentration to reduce the overall cost, aiming to obtain a biomass concentration similar to that obtained with the reference LAB culture medium (de Man, Rogosa and Sharpe; MRS). Sodium acetate and magnesium sulfate were the most significant factors (p < 0.005), and their contents were reduced by 22 % and 40 %, respectively, without affecting biomass concentration. Malt germ extract (MGE) was used as an alternative nitrogen source to replace meat extract (ME) and proteose peptone (PP). Through these experiments, the composition of a culture medium that is less expensive than MRS broth was defined, which produced a biomass concentration (3.8 g/L) similar to that obtained with MRS medium. The inhibitory effects of two LAB strains isolated from the Ivory Coast and Mexico on the growth and production of ochratoxin A (OTA) in an ochratoxigenic fungus was tested. The minimum cellular concentration of the LAB to prevent the development of Aspergillus carbonarius Ac 089 and the production of OTA was determined in a model assay in Petri dishes. The conditions to inhibit the germination of A. carbonarius Ac 089 and the production of OTA were found. Using the optimized medium and a ratio of 2 × 104 LAB/spore (1 × 108 CFU/mL) strain B7 (L. plantarum MZ809351) and 2 × 103 LAB/spore (1 × 107 CFU/mL) strain B31 (L. plantarum MN922335) completely inhibited the growth of the fungus. A ratio of 2 × 105 LAB/spore (1 × 109 CFU/mL) was required to inhibit OTA production with strains B7 and B31. This study indicates the potential of cultivating LAB in an optimized and inexpensive culture medium for use as a biological control agent against ochratoxigenic fungi in food.


Assuntos
Lactobacillales , Ocratoxinas , Humanos , Meios de Cultura , Nitrogênio/farmacologia , Extratos Vegetais
8.
J Evol Biol ; 25(3): 532-46, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22268676

RESUMO

Host-parasite systems have been models for understanding the connection between shifts in resource use and diversification. Despite theoretical expectations, ambiguity remains regarding the frequency and importance of host switches as drivers of speciation in herbivorous insects and their parasitoids. We examine phylogenetic patterns with multiple genetic markers across three trophic levels using a diverse lineage of geometrid moths (Eois), specialist braconid parasitoids (Parapanteles) and plants in the genus Piper. Host-parasite associations are mapped onto phylogenies, and levels of cospeciation are assessed. We find nonrandom patterns of host use within both the moth and wasp phylogenies. The moth-plant associations in particular are characterized by small radiations of moths associated with unique host plants in the same geographic area (i.e. closely related moths using the same host plant species). We suggest a model of diversification that emphasizes an interplay of factors including host shifts, vicariance and adaptation to intraspecific variation within hosts.


Assuntos
Cadeia Alimentar , Interações Hospedeiro-Patógeno/genética , Mariposas/genética , Mariposas/parasitologia , Piper/genética , Árvores , Vespas/genética , Animais , Sequência de Bases , Teorema de Bayes , Biologia Computacional , Costa Rica , DNA Mitocondrial/genética , Equador , Evolução Molecular , Especiação Genética , Interações Hospedeiro-Patógeno/fisiologia , Larva/parasitologia , Larva/fisiologia , Modelos Genéticos , Dados de Sequência Molecular , Mariposas/classificação , Mariposas/fisiologia , Filogenia , Análise de Sequência de DNA , Vespas/fisiologia
9.
Nat Commun ; 13(1): 1675, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35354815

RESUMO

The epidemiology of infectious causes of meningitis in sub-Saharan Africa is not well understood, and a common cause of meningitis in this region, Mycobacterium tuberculosis (TB), is notoriously hard to diagnose. Here we show that integrating cerebrospinal fluid (CSF) metagenomic next-generation sequencing (mNGS) with a host gene expression-based machine learning classifier (MLC) enhances diagnostic accuracy for TB meningitis (TBM) and its mimics. 368 HIV-infected Ugandan adults with subacute meningitis were prospectively enrolled. Total RNA and DNA CSF mNGS libraries were sequenced to identify meningitis pathogens. In parallel, a CSF host transcriptomic MLC to distinguish between TBM and other infections was trained and then evaluated in a blinded fashion on an independent dataset. mNGS identifies an array of infectious TBM mimics (and co-infections), including emerging, treatable, and vaccine-preventable pathogens including Wesselsbron virus, Toxoplasma gondii, Streptococcus pneumoniae, Nocardia brasiliensis, measles virus and cytomegalovirus. By leveraging the specificity of mNGS and the sensitivity of an MLC created from CSF host transcriptomes, the combined assay has high sensitivity (88.9%) and specificity (86.7%) for the detection of TBM and its many mimics. Furthermore, we achieve comparable combined assay performance at sequencing depths more amenable to performing diagnostic mNGS in low resource settings.


Assuntos
Meningite , Mycobacterium tuberculosis , Tuberculose Meníngea , Sistema Nervoso Central , Humanos , Meningite/microbiologia , Metagenômica , Mycobacterium tuberculosis/genética , Tuberculose Meníngea/líquido cefalorraquidiano , Tuberculose Meníngea/diagnóstico , Tuberculose Meníngea/genética
10.
Toxicol In Vitro ; 70: 105011, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33038467

RESUMO

Perfluorohexane sulfonate (PFHxS) is one of the most abundant perfluorinated compounds in the environment. Exposure to this compound has been correlated to a decrease in human fertility, although the molecular and cellular mechanisms underlying this correlation have not been described. The adverse reproductive effects of PFHxS could be based on alterations in oocyte maturation, the process rendering oocytes competent for fertilization. The aim of this study was to evaluate the effect of PFHxS on porcine oocyte viability and maturation in vitro, as well as on gap-junctional intercellular communication (GJIC) in cumulus-oocyte complexes (COCs), oocyte mitochondrial membrane potential (mΔΨ) and DNA damage in cumulus cells, as possible mechanisms of action. PFHxS caused cytotoxicity (medium lethal concentration, LC50 = 329.1 µM) and inhibition of oocyte maturation (medium inhibitory concentration, MIC50 = 91.68 µM). GJIC was not affected in exposed COCs. However, the mitochondrial membrane potential was significantly decreased in PFHxS-exposed oocytes at the germinal vesicle breakdown (GVBD) stage. In addition, exposure to PFHxS induced DNA damage in cumulus cells. Thus, inhibition of oocyte maturation by PFHxS could be attributed to a decreased oocyte mΔΨ at the GVBD and to DNA damage of the cumulus cells that support the oocyte.


Assuntos
Células do Cúmulo/efeitos dos fármacos , Ácidos Sulfônicos/toxicidade , Animais , Comunicação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células do Cúmulo/fisiologia , Dano ao DNA , Feminino , Fluorocarbonos , Junções Comunicantes/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Suínos
11.
Urol Case Rep ; 33: 101373, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33102072

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) infections are cases of urgent management that often leads to hospitalizations in intensive care and prolonged management of antibiotic therapy. In this occasion, we present the case of a 38-year-old female patient with sepsis secondary to banal dermal infection due MRSA that complicates with infectious thrombus of the left renal vein associated with multiple foci of bilateral renal abscesses. As an extreme and exceptional measure, emergency bilateral radical nephrectomy was performed to save the patient's life.

12.
Bioresour Technol ; 265: 291-298, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29909359

RESUMO

A novel bench-scale stirred bioreactor for solid-state fermentation was used to determine the effect of the stirring rate on growth and enzymes production by Trichoderma harzianum PBLA. Lab-scale static tubular bioreactors were first used to assess the effect of bioreactor diameter on heat accumulation, growth, and production of cellulases and xylanases. The increased diameters (1.8-4.2 cm) led to increases in temperature up to 36 °C (at a rate of 1.08 °C/cm), which negatively affected the growth and enzyme production. Afterward, in the bench-scale bioreactor operated at rates up to 3.0 rpm, maximum xylanases production (107 ±â€¯0.3 U/g dm) was attained at rates of 0.5 and 1.0 rpm, reaching a maximum of 34 ±â€¯0.3 °C. Cellulases production was reduced (up to 79%) due to stirring. Therefore, the production of xylanases by T. harzianum can be performed in this cross-flow stirred SSF bioreactor at rates up to 1.0 rpm, avoiding heat accumulation and damage on metabolic activity.


Assuntos
Reatores Biológicos , Fermentação , Trichoderma , Celulases , Temperatura
13.
Curr Opin Insect Sci ; 14: 73-80, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-27436650

RESUMO

Ants are keystone predators in terrestrial trophic cascades. Addressing ants' roles in multitrophic interactions across regional gradients is important for understanding mechanisms behind range limits of species. We present four hypotheses of trophic dynamics occurring when ants are rare: first, there is a shift in predator communities; second, plants decrease investments in ant attraction and increase production of secondary metabolites; third, lower herbivory at high elevations allows plants to tolerate herbivory; and fourth, distribution of ant-plants can be limited based on ant abundance. Conducting experiments on multitrophic effects of ants across elevational gradients, and incorporating these results to ecological niche modeling (ENM) will improve our knowledge of the impacts of global change on ants, trophic interactions, and biodiversity.


Assuntos
Formigas/fisiologia , Ecossistema , Herbivoria , Comportamento Predatório/fisiologia , Temperatura , Animais , Interações Hospedeiro-Parasita , Plantas/parasitologia
14.
O.F.I.L ; 30(4): 343-346, 2020. tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-197511

RESUMO

El uso conjunto de medicamentos anticolinérgicos e inhibidores de la colinesterasa no es recomendado por los fabricantes de los productos, ya que pueden afectar la función cognitiva de los pacientes, esto se ve acentuado en la población geriátrica polimedicada. Uno de los problemas relacionados a la medicación, en los que los farmacéuticos realizan con frecuencia intervenciones, es el número de interacciones farmacológicas potenciales que pueden expresarse con los distintos medicamentos que emplean los pacientes. Presentamos el caso de un paciente con diagnóstico de Parkinson y vejiga neurogénica que presentó pérdida de la concentración y memoria asociada a una interacción farmacológica entre un inhibidor directo de la colinesterasa (rivastigmina) y un anticolinérgico (tolterodina). El mecanismo descrito para la interacción es la disminución del efecto esperado de rivastigmina por efecto de inhibición de la tolterodina en los receptores colinérgicos, impidiendo la liberación de acetilcolina y quitando así el blanco terapéutico de la enzima que se inhibe por efecto de la tolterodina. La intervención oportuna y el manejo adecuado de las interacciones farmacológicas durante la atención sanitaria es de suma importancia para evitar daños en los pacientes, incluido la exacerbación de enfermedades que se encuentran controladas, debido a la adición de otros medicamentos a la farmacoterapia


The use of anticholinergic and cholinesterase inhibitors set is not recommended by drug laboratory producers, because the use of the drugs can affect the cognitive function of the patients, this is more common in the elderly and polymedicated population. For the pharmacist is a challenge to have control of the number of potential drug interactions that can express with the different drugs that the patient has in a prescription. We present a case of an expression of drug-drug interaction between anticholinergic (tolterodine) and direct cholinesterase inhibitor (rivastigmine) in a patient with Parkinson disease and overactive bladder, the outcome of this interaction is the decrease the effect of rivastigmine by inhibition of cholinergic receptors, keep the inhibition of release acetylcholine and remove the target of the enzyme that rivastigmine inhibit, the expression of the interaction in the patient is expressed in loss of concentration and memory, the management and report of this interaction is very important for the patient with control of the disease


Assuntos
Humanos , Masculino , Idoso , Rivastigmina/farmacologia , Inibidores da Colinesterase/farmacologia , Tartarato de Tolterodina/farmacologia , Antagonistas Muscarínicos/farmacologia , Doença de Parkinson/tratamento farmacológico , Bexiga Urinária Hiperativa/tratamento farmacológico , Interações Medicamentosas , Escala de Coma de Glasgow , Resultado do Tratamento , Fatores de Tempo
15.
Bioresour Technol ; 193: 534-44, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26159377

RESUMO

With increasing focus on sustainable energy, bio-refining from lignocellulosic biomass has become a thrust area of research. With most of the works being focused on biofuels, significant efforts are also being directed towards other value added products. Feruloyl esterases (EC. 3.1.1.73) can be used as a tool for bio-refining of lignocellulosic material for the recovery and purification of ferulic acid and related hydroxycinnamic acids ubiquitously found in the plant cell wall. More and more genes coding for feruloyl esterases have been mined out from various sources to allow efficient enzymatic release of ferulic acid and allied hydroxycinnamic acids (HCAs) from plant-based biomass. A sum up on enzymatic extraction of HCAs and its recovery from less explored agro residual by-products is still a missing link and this review brushes up the achieved landmarks so far in this direction and also covers a detailed patent search on this biomass refining enzyme.


Assuntos
Biomassa , Biotecnologia/métodos , Hidrolases de Éster Carboxílico/metabolismo , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Fermentação
16.
Bioresour Technol ; 180: 112-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25594506

RESUMO

The effect of pH, C/N ratio, addition of a microbial consortium (MC) and temperature upon mineralisation of Organic Fraction of Municipal Solid Waste (OFMSW) was studied; mineralisation was measured through the CO2 production rate and total CO2 formation. Through this process up to 432.9mg of CO2g(-1) initial dry matter (IDM) after 2days of treatment was obtained. It was found that under a slightly acidic pH (5-6) and C/N of 30, the mineralisation process was accelerated. Moreover, temperature (27-50°C) had no effect on the total CO2 produced. The highest CO2 production rate (5.28d(-1)) was observed at 27°C, C/N ratio of 30 and 8% of microbial consortium; it is at least 3.52 times higher than that reported (1.5d(-1)). The highest release of reducing sugars was determined at 50°C, possibly due to an increase in hydrolytic enzymes. Results suggest the potential use of rapid mineralisation of OFMSW for further friendly environmental processes.


Assuntos
Consórcios Microbianos , Eliminação de Resíduos/métodos , Aerobiose , Carbono/metabolismo , Dióxido de Carbono/análise , Concentração de Íons de Hidrogênio , Minerais/química , Nitrogênio/metabolismo , Resíduos Sólidos , Temperatura
17.
Biotechnol Prog ; 18(4): 728-33, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12153305

RESUMO

Addition of toluene into slurry phase laboratory microcosm is proposed in order to increase desorption rate of hydrocarbons and as an alternative to improve bioavailability of hydrocarbon in aged soils. Our studies showed that toluene has a positive effect on desorption of total petroleum hydrocarbons (TPH). Addition of 14,000 mg toluene/kg of soil, in highly polluted soil, increased the consumption rate of hydrocarbons three times in comparison to control without solvent. In 30 days the initial TPH concentration in soil, 292,000 mg/kg, diminished 45%. Although toluene was able to dissolve complex organic compounds such as asphaltene fraction, it probably yielded a highly toxic toluene-hydrocarbons phase. The inhibitory effect of toluene-TPH was also studied. A substrate inhibition model was used: the k(m) and k(i) constants were 57 and 490 mg TPH/L liquid phase, respectively. Experimental data were well described when the proposed model included sequential desorption and biodegradation phenomena. Damköhler number evaluation showed that rate of mass transfer was the limiting step in overall biodegradation in nonsolvent control. When high concentration of toluene was added, then bioreaction was the limiting step, but inhibitory effect should be considered. However, toluene addition at low concentrations facilitates the biodegradation of aromatic compounds.


Assuntos
Hidrocarbonetos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Tolueno/química , Adsorção , Biodegradação Ambiental , Meios de Cultura , Hidrocarbonetos/química , Cinética , Modelos Biológicos , Petróleo/metabolismo , Solventes/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-12954390

RESUMO

A capillary zone electrophoretic (CZE) method was investigated for the determination of Gleevec and its main metabolite (N-demethylated piperazine derivative) in human urine using a fused-silica capillary (75 microm I.D.x60 cm total length, 10 cm effective length). The separation was performed with an hydrodynamic injection time of 10 s (0.5 p.s.i.) a voltage of -25 kV, a capillary temperature of 25 degrees C and a 100 mM phosphoric acid adjusted to pH 2 with the addition of triethanolamine. Under these conditions, the analysis takes about 5 min. A linear response over the 0.4-30.0 mg l(-1) concentration range was investigated for two compounds. A dilution of the sample was the only step necessary before the electrophoresis analysis. Detection limits of 0.1 mg l(-1) for Gleevec and its metabolite (S/N=3) were obtained. The developed method is easy, rapid and sensitive and has been applied to determine Gleevec and its main metabolite in clinical urine samples.


Assuntos
Antineoplásicos/urina , Eletroforese Capilar/métodos , Piperazinas/urina , Pirimidinas/urina , Benzamidas , Soluções Tampão , Humanos , Concentração de Íons de Hidrogênio , Mesilato de Imatinib , Reprodutibilidade dos Testes , Temperatura
19.
J Child Neurol ; 13(6): 283-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9660512

RESUMO

Numerous studies have suggested that epilepsy and asthma may be related conditions. There has, however, been little epidemiologic data published to support this association. We conducted a retrospective study to determine whether the prevalence of epilepsy is increased among children with asthma, and the prevalence of asthma is increased among children with epilepsy, in comparison with the general pediatric population. We reviewed the medical records, at a large city hospital, of two groups of pediatric outpatients: (1) 400 consecutive patients with asthma followed regularly at the asthma and allergy clinic; and (2) 201 consecutive patients with idiopathic epilepsy followed regularly at the pediatric neurology clinic. Patients with a history of birth prior to 36 weeks' gestational age were excluded. Among the 400 cases of asthma, there were three patients with idiopathic epilepsy (prevalence of 0.75%). The prevalence of epilepsy was similar in mild (0.79%) and moderate-to-severe (0.73%) asthma. Among the 201 cases of idiopathic epilepsy, there were 12 patients with asthma (prevalence of 5.97%). Similar percentages of epilepsy patients with and without asthma reported generalized tonic-clonic, complex partial, simple partial, and myoclonic seizures as their predominant type. The prevalence values in this study are consistent with the prevalence of epilepsy and asthma in the general pediatric population. Our findings therefore suggest that idiopathic epilepsy and asthma are not etiologically related or mutually predisposing conditions. Small samples, failure to exclude patients born prematurely, and the equation of electroencephalographic (EEG) abnormalities with epilepsy may account for the results of previous studies.


Assuntos
Asma/complicações , Epilepsia/complicações , Asma/diagnóstico , Eletroencefalografia , Epilepsia/diagnóstico , Humanos , Lactente , Prontuários Médicos , Estudos Retrospectivos , Índice de Gravidade de Doença
20.
Talanta ; 50(2): 261-8, 1999 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-18967716

RESUMO

A method for quantifying of ethinylestradiol (ETE) and levo-norgestrel (LEV) in pharmaceutical products by micellar electrokinetic chromatography (MEKC) is described. The separation was carried out at 25 degrees C and 25 kV, using a 20 mM borate buffer (pH 9.2), 15 mM sodium dodecylsulfate (SDS) in 30% acetonitrile/water (v/v). Under these conditions the analysis takes about 7 min. The method has been applied for quantifying both compounds in six different commercial contraceptives and the proposed method gave good results when compared with a reference liquid chromatographic (LC) method.

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