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1.
Sci Rep ; 11(1): 168, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420221

RESUMO

Since the first studies on bowhead whale singing behaviour, song variations have been consistently reported. However, there has been little discussion regarding variability in bowhead whale singing display and its ecological significance. Unlike the better studied humpback whales, bowhead whales do not appear to share songs at population level, but several studies have reported song sharing within clusters of animals. Over the winter season 2013-2014, in an unstudied wintering ground off Northeast Greenland, 13 song groups sharing similar hierarchical structure and units were identified. Unit types were assessed through multidimensional maps, showing well separated clusters corresponding to manually labelled units, and revealing the presence of unit subtypes. Units presented contrasting levels of variability over their acoustic parameters, suggesting that bowhead whales keep consistency in some units while using a continuum in values of frequency, duration and modulation parameters for other unit types. Those findings emphasise the need to account for variability in song analysis to better understand the behavioural ecology of this endangered species. Additionally, shifting from song toward units or phrase-based analysis, as it has been suggested for humpback whales, offers the opportunity to identify and track similarities in songs over temporal and geographical scales relevant to population monitoring.


Assuntos
Baleia Franca , Fenômenos Ecológicos e Ambientais , Vocalização Animal , Animais , Estações do Ano
2.
Sci Rep ; 7: 45517, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28401960

RESUMO

Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems.

3.
Mar Pollut Bull ; 63(1-4): 18-26, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21665016

RESUMO

The development and broad use of passive acoustic monitoring techniques have the potential to help assessing the large-scale influence of artificial noise on marine organisms and ecosystems. Deep-sea observatories have the potential to play a key role in understanding these recent acoustic changes. LIDO (Listening to the Deep Ocean Environment) is an international project that is allowing the real-time long-term monitoring of marine ambient noise as well as marine mammal sounds at cabled and standalone observatories. Here, we present the overall development of the project and the use of passive acoustic monitoring (PAM) techniques to provide the scientific community with real-time data at large spatial and temporal scales. Special attention is given to the extraction and identification of high frequency cetacean echolocation signals given the relevance of detecting target species, e.g. beaked whales, in mitigation processes, e.g. during military exercises.


Assuntos
Monitoramento Ambiental/métodos , Ruído/efeitos adversos , Vocalização Animal , Baleias/fisiologia , Acústica , Animais , Percepção Auditiva , Ecolocação , Monitoramento Ambiental/instrumentação , Ruído/prevenção & controle , Oceanos e Mares
4.
J Aquat Anim Health ; 22(3): 190-218, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21192549

RESUMO

Skin lesions and spring mortality events of smallmouth bass Micropterus dolomieu and selected other species were first noted in the South Branch of the Potomac River in 2002. Since that year morbidity and mortality have also been observed in the Shenandoah and Monocacy rivers. Despite much research, no single pathogen, parasite, or chemical cause for the lesions and mortality has been identified. Numerous parasites, most commonly trematode metacercariae and myxozoans; the bacterial pathogens Aeromonas hydrophila, Aeromonas salmonicida, and Flavobacterium columnare; and largemouth bass virus have all been observed. None have been consistently isolated or observed at all sites, however, nor has any consistent microscopic pathology of the lesions been observed. A variety of histological changes associated with exposure to environmental contaminants or stressors, including intersex (testicular oocytes), high numbers of macrophage aggregates, oxidative damage, gill lesions, and epidermal papillomas, were observed. The findings indicate that selected sensitive species may be stressed by multiple factors and constantly close to the threshold between a sustainable (healthy) and nonsustainable (unhealthy) condition. Fish health is often used as an indicator of aquatic ecosystem health, and these findings raise concerns about environmental degradation within the Potomac River drainage. Unfortunately, while much information has been gained from the studies conducted to date, due to the multiple state jurisdictions involved, competing interests, and other issues, there has been no coordinated approach to identifying and mitigating the stressors. This synthesis emphasizes the need for multiyear, interdisciplinary, integrative research to identify the underlying stressors and possible management actions to enhance ecosystem health.


Assuntos
Doenças dos Peixes/mortalidade , Perciformes , Rios , Animais , Ecossistema , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/microbiologia , Fatores de Tempo
5.
Bull Environ Contam Toxicol ; 82(6): 653-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19290448

RESUMO

Four wells downgradient from a landfill near Elkhart, Indiana were sampled during 2000-2002 to evaluate the presence of waste-indicator and pharmaceutical compounds in landfill-leachate-affected ground water. Compounds detected in leachate-affected ground water included detergent metabolites (p-nonylphenol, nonylphenol monoethoxylate, nonylphenol diethoxylate, and octylphenol monoethoxylate), plasticizers (ethanol-2-butoxy-phosphate and diethylphthalate), a plastic monomer (bisphenol A), disinfectants (1,4-dichlorobenzene and triclosan), an antioxidant (5-methyl-1H-benzotriazole), three fire-retardant compounds (tributylphosphate and tri(2-chloroethyl)phosphate, and tri(dichlorisopropyl)phosphate), and several pharmaceuticals and metabolites (acetaminophen, caffeine, cotinine, 1,7-dimethylxanthine, fluoxetine, and ibuprofen). Acetaminophen, caffeine, and cotinine detections confirm prior indications of pharmaceutical and nicotinate disposal in the landfill.


Assuntos
Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Resíduos Perigosos/análise , Indiana , Resíduos Industriais/análise , Resíduos de Serviços de Saúde/análise
6.
Chemosphere ; 61(5): 610-22, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16219498

RESUMO

Four water samples collected using standard depth and width water-column sampling methodology were compared to an innovative passive, in situ, sampler (the polar organic chemical integrative sampler or POCIS) for the detection of 96 organic wastewater-related contaminants (OWCs) in a stream that receives agricultural, municipal, and industrial wastewaters. Thirty-two OWCs were identified in POCIS extracts whereas 9-24 were identified in individual water-column samples demonstrating the utility of POCIS for identifying contaminants whose occurrence are transient or whose concentrations are below routine analytical detection limits. Overall, 10 OWCs were identified exclusively in the POCIS extracts and only six solely identified in the water-column samples, however, repetitive water samples taken using the standard method during the POCIS deployment period required multiple trips to the sampling site and an increased number of samples to store, process, and analyze. Due to the greater number of OWCs detected in the POCIS extracts as compared to individual water-column samples, the ease of performing a single deployment as compared to collecting and processing multiple water samples, the greater mass of chemical residues sequestered, and the ability to detect chemicals which dissipate quickly, the passive sampling technique offers an efficient and effective alternative for detecting OWCs in our waterways for wastewater contaminants.


Assuntos
Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Compostos Orgânicos/análise , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , New Jersey , Rios
7.
J Pharm Biomed Anal ; 24(5-6): 785-99, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11248471

RESUMO

The capillary electrophoretic separation and immunochemical recognition of the two naturally fluorescing, cationic diastereomers quinine (QN) and quinidine (QD), their hydroderivatives and two major QD metabolites (3-hydroxyquinidine and quinidine-N-oxide) was investigated. Plain aqueous phosphate buffers and an alkaline buffer containing dodecyl sulfate micelles are shown to be incapable of resolving the two diastereomers. However, incorporation of an additional chemical equilibrium (with beta-cyclodextrin) in the case of capillary zone electrophoresis (CZE) and the presence of a small amount of an organic solvent as buffer modifier (2-propanol) in dodecyl sulfate based micellar electrokinetic capillary chromatography (MECC), were found to provide separation media which lead to complete resolution of QN, QD and the other compounds of interest. Furthermore, for MECC- and CZE-based immunoassay formats, a commercially available antibody against QD was found to be a perfect discriminator between QD and QN. It was determined to recognize QD and the two QD metabolites (cross reactivity of 20--30%) but not QN. MECC and CZE with laser induced fluorescence (LIF) detection are shown to be suitable to determine QD and metabolites in urine and plasma (quinidine-N-oxide only) collected after single dose intake of 50 mg QD sulfate and of QN in urine, saliva and serum samples that were collected after self-administration of 0.5 l of quinine water (25 mg of QN). With direct injection of a body fluid, MECC with LIF was found to provide 10 ng/ml detection limits for QD and QN. This ppb sensitivity is comparable to that obtained in HPLC assays that are based upon drug extraction. Furthermore, MECC and CZE assays with UV detection are shown to provide the ppm sensitivity required for therapeutic drug monitoring and clinical toxicology of QD and QN.


Assuntos
Líquidos Corporais/metabolismo , Eletroforese Capilar/métodos , Imunoensaio/métodos , Quinidina/metabolismo , Cromatografia Capilar Eletrocinética Micelar/métodos , Relação Dose-Resposta a Droga , Humanos , Quinidina/sangue , Quinidina/química , Quinidina/urina , Sensibilidade e Especificidade , Estereoisomerismo
8.
J Chromatogr B Biomed Sci Appl ; 752(1): 17-31, 2001 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11254191

RESUMO

Acetylsalicylic acid (Aspirin) is rapidly metabolized to salicylic acid (salicylate) and other compounds, including gentisic acid and salicyluric acid. Monitoring of salicylate and its metabolites is of toxicological, pharmacological and biomedical interest. Three capillary electrophoresis (CE) methods featuring alkaline aqueous buffers, laser-induced fluorescence (LIF) detection and no solute extraction or derivatization have been explored. A competitive binding, electrokinetic capillary-based immunoassay is developed that recognizes the presence of salicylate and gentisic acid in urine. Differentiation of the two compounds, however, is problematic. With appropriate ultraviolet excitation, many salicylate-related compounds are fluorescent so that CE with direct urine injection and LIF detection permits the determination of salicylate, gentisic acid and salicyluric acid. Using a HeCd laser with 325 nm produces interference-free monitoring of all three compounds. Using 257 nm excitation from a frequency doubled Ar ion laser, native fluorescence of an endogenous urinary compound that co-migrates with gentisic acid is observed. With wavelength-resolved fluorescence detection, however, the two substances are distinguished. Furthermore, this technique, with comparison to literature data, permits the putative assignment of several peaks to other salicylate metabolites, namely glucuronide conjugates of salicylate and salicyluric acid. All three CE-LIF techniques have been applied to toxicological patient urines and urines collected after ingestion of 500 mg acetylsalicylic acid. CE results compare favorably with those obtained by a commercial fluorescence polarization immunoassay and by a conventional photometric assay.


Assuntos
Aspirina/urina , Eletroforese Capilar/métodos , Gentisatos , Hipuratos/urina , Hidroxibenzoatos/urina , Humanos , Imunoensaio/métodos , Espectrometria de Fluorescência
9.
J Chromatogr A ; 875(1-2): 27-41, 2000 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-10839138

RESUMO

During the past decade, chiral capillary electrophoresis (CE) emerged as a promising, effective and economic approach for the enantioselective determination of drugs in body fluids, hair and microsomal preparations. This review discusses the principles and important aspects of CE-based chiral bioassays, provides a survey of the assays developed and presents an overview of the key achievements encountered. Applications discussed encompass the pharmacokinetics of drug enantiomers, the elucidation of the stereoselectivity of drug metabolism and bioanalysis of drug enantiomers of toxicological and forensic interest.


Assuntos
Líquidos Corporais/química , Eletroforese Capilar/métodos , Preparações Farmacêuticas/análise , Humanos , Estereoisomerismo
10.
J Chromatogr A ; 838(1-2): 237-49, 1999 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-10327641

RESUMO

Using capillary zone electrophoresis (CZE) with a 75 mM phosphate buffer at pH 8.5 containing 5 mM hydroxypropyl-gamma-cyclodextrin (OHP-gamma-CD) as chiral selector, the separation of the enantiomers of thiopental and its oxybarbiturate metabolite, pentobarbital, is reported. Enantiomer assignment was performed via preparation of enantiomerically enriched fractions using chiral recycling isotachophoresis (rITP) processing of racemic barbiturates and analysis of rITP fractions by chiral CZE and circular dichroism spectroscopy. Thiopental and pentobarbital enantiomers in plasma were extracted at low pH using dichloromethane and extracts were reconstituted in acetonitrile or 10-fold diluted, achiral running buffer. The stereoselectivity of the thiopental and pentobarbital metabolism was assessed via analysis of 12 plasma samples that stemmed from patients undergoing prolonged or having completed long-term racemic thiopental infusion. The data obtained revealed a modest stereoselectivity with R-(+)-thiopental/S-(-)-thiopental and R-(+)-pentobarbital/S-(-)-pentobarbital plasma ratios being < 1 (P < 0.05 compared to data obtained with racemic controls) and > 1 (P < 0.001), respectively. The total S-(-)-thiopental plasma concentration was found to be on average about 24% higher compared to the concentration of R-(+)-thiopental, whereas the total R-(+)-pentobarbital plasma level was observed to be on average 29% higher compared to the S-(-)-pentobarbital concentration.


Assuntos
Eletroforese Capilar/métodos , Pentobarbital/sangue , Tiopental/sangue , beta-Ciclodextrinas , gama-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Soluções Tampão , Dicroísmo Circular , Ciclodextrinas , Humanos , Concentração de Íons de Hidrogênio , Cloreto de Metileno , Pentobarbital/química , Fosfatos , Estereoisomerismo , Tiopental/química
11.
Electrophoresis ; 18(2): 202-4, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9080126

RESUMO

Bacterial-facilitated depletion of cyanide is under development for remediation of heap leach operations in the gold mining industry. Capillary electrophoresis was found to be a powerful tool for quantifying cyanide depletion. Changes in cyanide concentration in aqueous suspensions of Pseudomonas alcaligenes bacteria and cyanide at elevated pH were easily monitored by capillary electrophoresis. The resulting data can be used to study rates of cyanide depletion by this strain of bacteria. Concentrations of these bacteria at 10(5) cells/mL were found to reduce cyanide from 100 ppm to less than 8 ppm in four days. In addition, other ions of interest in cyanide metabolism, such as formate, can be simultaneously analyzed. Direct UV detection of cyanide at 192 nm further simplifies the analytical method for these ions.


Assuntos
Cianetos/análise , Eletroforese Capilar , Pseudomonas/metabolismo , Meios de Cultura/química
12.
Anesth Analg ; 83(4): 760-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8831317

RESUMO

Postoperative analgesia may be prolonged by the addition of clonidine to local anesthetic solutions used for regional anesthesia. The purpose of this study was to test this hypothesis in a clinical trial of patients undergoing podiatric surgery. The study design was prospective, double-blinded, and randomized. Ninety ASA physical status I or II patients scheduled for bunionectomy or hammer toe repair were randomized to receive ankle or metatarsal blocks with plain 1.73% lidocaine (Group L), 1.73% lidocaine with 10 micrograms/mL of clonidine added (Group C10), or 1.73% lidocaine with 20 micrograms/mL clonidine (Group C20). Time from the performance of the block to 1) loss of sensation to pinprick, 2) return of sensation to pinprick, 3) onset of postsurgical pain, and 4) time of first oral pain medication intake were recorded. Beginning at 1 h after the completion of the block, visual analog scale (VAS) and verbal pain scores were recorded every 30 min. Additional postoperative oral pain medication required in the first 9 h after the block was also recorded. Analysis of variance (ANOVA) was used to analyze intergroup differences in the VAS and verbal pain scores, the time to first reported pain, the time to first oral pain medication, and the total amount of oral pain medications required. Repeated-measures ANOVA was used to analyze the VAS and verbal pain scores overall and integrated assessment of pain scores and rescue medication was per-formed. Adverse events were also recorded for each group. There were no differences among the three groups with regard to overall VAS pain scores although Group C10 had significantly better verbal pain scores after the first 3 h (P < 0.05). There was also no difference in time to loss or return of pinprick sensation. Group C10 had a longer time to first reported pain (P < 0.01), a longer time to first oral pain medication (P < 0.01), a lower average total dose of oral pain medication required (P < 0.05), and a lower integrated assessment of pain and medication (P < 0.01) than Group L. More patients in Group C10 reported no pain postoperatively (P < 0.01) and no pain medication taken (P < 0.01) than Group L. Group C20 results suggested no statistically significant improvement over plain lidocaine. One patient in Group C20 experienced significant hypotension postoperatively. pH determinations and chemical analysis by capillary electrophoresis showed no significant change in composition of the solutions when clonidine was mixed with lidocaine and stored at 4 degrees C for 1 wk. Compared to 1.73% lidocaine, combining clonidine (10 micrograms/mL) with lidocaine for local anesthetic block for foot surgery significantly increases the duration and quality of postoperative analgesia.


Assuntos
Agonistas alfa-Adrenérgicos/uso terapêutico , Analgesia , Analgésicos/uso terapêutico , Anestésicos Locais/uso terapêutico , Clonidina/uso terapêutico , Doenças do Pé/cirurgia , Lidocaína/uso terapêutico , Bloqueio Nervoso , Dor Pós-Operatória/tratamento farmacológico , Agonistas alfa-Adrenérgicos/administração & dosagem , Agonistas alfa-Adrenérgicos/efeitos adversos , Agonistas alfa-Adrenérgicos/química , Adulto , Analgésicos/administração & dosagem , Analgésicos/efeitos adversos , Analgésicos/química , Análise de Variância , Anestésicos Locais/administração & dosagem , Anestésicos Locais/efeitos adversos , Anestésicos Locais/química , Tornozelo/inervação , Clonidina/administração & dosagem , Clonidina/efeitos adversos , Clonidina/química , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Hallux Valgus/cirurgia , Humanos , Hipotensão/induzido quimicamente , Lidocaína/administração & dosagem , Lidocaína/efeitos adversos , Lidocaína/química , Masculino , Metatarso/inervação , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/etiologia , Estudos Prospectivos , Sensação/efeitos dos fármacos , Fatores de Tempo , Dedos do Pé/anormalidades , Dedos do Pé/cirurgia
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