Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Spinal Cord ; 52 Suppl 1: S17-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24513720

RESUMO

STUDY DESIGN: We present a case report describing the multidisciplinary treatment of a tetraplegic spinal cord injury (SCI) patient who developed an acute exacerbation of chronic central pain. OBJECTIVE: To bring further awareness to the importance of using a comprehensive, multidisciplinary approach in treating acute exacerbation of chronic central pain in SCI patients. SETTING: University of California Irvine Medical Center, Orange, CA, USA. CASE REPORT: We present a 34-year-old man with a past medical history of C5 American Spinal Injury Association B tetraplegia secondary to a surfing accident 8 years prior, central pain syndrome, spasticity, autonomic dysreflexia and anxiety who arrived at the emergency room with a 1-month history of worsening acute on chronic pain refractory to opioid escalation. The multispecialty treatment plan included treatment of the patient's urinary tract infection by the primary medicine service, management of the patient's depression by the psychiatric service, treatment of bowel obstruction by general surgery and adjustment of pain medications by pain management. The patient was found to have stable neurological findings, neuroimaging unchanged from prior imaging and a urinary tract infection. Hospitalization was complicated by severe colonic dilation that required disimpaction by general surgery. CONCLUSION: The treatment of this patient's acutely worsened central pain highlights the importance of applying a multidisciplinary approach to SCI patients with an acute exacerbation of chronic central pain. In this case, the multispecialty treatment plan included treatment of the patient's urinary tract infection by the primary medicine service, management of the patient's depression by the psychiatric service, treatment of bowel obstruction by general surgery, and adjustment of pain medications by pain management.


Assuntos
Sistema Nervoso Central/fisiopatologia , Manejo da Dor , Dor/etiologia , Quadriplegia/complicações , Adulto , Ansiedade/etiologia , Disreflexia Autonômica/etiologia , Humanos , Masculino
2.
Curr Rev Musculoskelet Med ; 3(1-4): 3-10, 2010 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-21063493

RESUMO

Posterior knee pain is a common patient complaint. There are broad differential diagnoses of posterior knee pain ranging from common causes such as injury to the musculotendinous structures to less common causes such as osteochondroma. A precise understanding of knee anatomy, the physical examination, and of the differential diagnosis is needed to accurately evaluate and treat posterior knee pain. This article provides a review of the anatomy and important aspects of the history and physical examination when evaluating posterior knee pain. It concludes by discussing the causes and management of posterior knee pain.

3.
Talanta ; 77(5): 1821-9, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19159805

RESUMO

In this paper, we describe a validation procedure for chemical fractionation analysis of elements (Al, As, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, S, Sb, Si, Sr, Ti and V) and soluble ions (Cl(-), NO(3)(-), SO(4)(2-), Na(+), NH(4)(+), Mg(2+), Ca(2+)) in suspended particulate matter (PM). The procedure applies three distinct measurement techniques (XRF, IC and ICP-OES) to the analysis of individual samples. The techniques used generate different outputs at different stages in the procedure. This makes it possible to identify the contributions of specific parameters to measurement uncertainty. On this basis, we propose a scheme for controlling the analytical quality of data from individual samples in which inter-technique comparisons is used in the same way many analytical methods use surrogates. We apply this scheme to about 310 samples of PM(10) and PM(2.5) identifying and assessing the main factors contributing to measurement uncertainty. This procedure successfully resolved a number of difficulties frequently encountered during the analysis of PM, including lack of appropriate reference materials and the low reliability of alternative techniques of quality control. The results demonstrate the critical importance of sample treatment prior to destructive analysis by IC and ICP.


Assuntos
Técnicas de Química Analítica/métodos , Íons/análise , Metais/análise , Material Particulado/análise , Controle de Qualidade
4.
Theor Appl Genet ; 111(8): 1514-23, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16187118

RESUMO

We constructed a Brassica napus genetic map with 240 simple sequence repeats (SSR) primer pairs from private and public origins. SSR, or microsatellites, are highly polymorphic and efficient markers for the analysis of plant genomes. Our selection of primer pairs corresponded to 305 genetic loci that we were able to map. In addition, we also used 52 sequence-characterized amplified region primer pairs corresponding to 58 loci that were developed in our lab. Genotyping was performed on six F2 populations, corresponding to a total of 574 F2 individual plants, obtained according to an unbalanced diallel cross design involving six parental lines. The resulting consensus map presented 19 linkage groups ranging from 46.2 to 276.5 cM, which we were able to name after the B. napus map available at http://ukcrop.net/perl/ace/search/BrassicaDB , thus enabling the identification of the A genome linkage groups originating from the B. rapa ancestor and the C genome linkage groups originating from the B. oleracea ancestor in the amphidiploid genome of B. napus. Some homologous regions were identified between the A and the C genomes. This map could be used to identify more markers, which would eventually be linked to genes controlling important agronomic characters in rapeseed. Furthermore, considering the good genome coverage we obtained, together with an observed homogenous distribution of the loci across the genome, this map is a powerful tool to be used in marker-assisted breeding.


Assuntos
Brassica napus/genética , Mapeamento Cromossômico , Repetições de Microssatélites/genética , Polimorfismo Genético , Cruzamentos Genéticos , Genótipo , Sintenia/genética
7.
Water Sci Technol ; 50(12): 1-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15685997

RESUMO

State-of-the-art information is presented on the analysis, by transmission electron microscopy (TEM), of aquatic colloidal particles in the size range of 3 to 500 nm least dimension, with a focus on nanoparticles (1-100 nm). Case studies include selections from both natural waters and waters undergoing treatment. The "species" of nano-particles receiving the greatest attention are: humic substances, polysaccharide fibrils, hydrous iron oxides, viruses, clay minerals, refractory cell debris, and heavy metal agglomerates on biological surfaces. Artifacts and how to both detect and minimize them are outlined. Correlative use of TEM with other imaging techniques is emphasized, along with associated spectroscopy. Noted is the potential of computerized image analysis for quantifying colloids on a "per colloid species" basis, using water samples centrifuged onto electron microscope grids.


Assuntos
Microscopia Eletrônica/métodos , Purificação da Água/métodos , Água/química , Coloides/química , Nanotecnologia , Tamanho da Partícula , Água/análise
8.
J Microsc ; 207(Pt 3): 180-90, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12230488

RESUMO

Analytical electron microscopy was used to characterize aquatic iron-rich colloids. We focused our attention on a redox transition medium in the drainage water of a peat soil. In the anoxic peat water, observations by transmission electron microscopy and associated energy dispersive analyses (TEM-EDS) highlight the presence of spherical entities (approximately 100-600 nm), containing only traces of iron. The increase of dissolved oxygen concentration favours the formation of iron oxy(hydr)oxides. In the oxygenated drain, particles with the same morphology and size range are present. Statistical TEM-EDS analyses show that they represent the only colloidal form of iron in the drain samples. Nevertheless, although Fe-K peaks appear clearly on EDS spectra, the proportion of iron in these colloids reaches at most 4% at. (whereas C + O > 90% at.). Structural information completes this study. Both electron spectroscopic imaging (ESI) and electron energy-loss spectroscopy (EELS) reveal the disparity between element distributions within the drain entities. Iron and calcium are preferably distributed on the outer sphere of the particle, whereas carbon and oxygen follow the theoretical variation of the signal intensity within a plain sphere. The implication of organic matter as nucleation site for iron precipitation is spectacularly demonstrated by the presence of nanometre-sized iron-rich phases highlighted by EELS line scans.


Assuntos
Coloides/química , Microscopia Eletrônica/métodos , Água/química , Elétrons
9.
J AOAC Int ; 84(5): 1407-12, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11601459

RESUMO

A simple method is described for the simultaneous determination of residues of 2 carbamate herbicides (phenmedipham and desmedipham) and related metabolites (m-aminophenol, aniline, and m-toluidine) in soil. The analytes are extracted from spiked soils with methanol. The solvent/soil suspension is centrifuged, and the supernatant is directly injected, without any further cleanup, into a reversed-phase liquid chromatography/mass spectrometry apparatus equipped with a TurbolonSpray interface. The method was tested on 5 soils having different physicochemical properties. Recoveries from the soil types, spiked over the range of 50-200 ppb, were essentially quantitative for each analyte. The detection limits of the method are < or = 25 ng/g.


Assuntos
Carbamatos/análise , Herbicidas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Solo/análise , Fenômenos Químicos , Físico-Química , Cromatografia Líquida , Espectrometria de Massas , Padrões de Referência , Reprodutibilidade dos Testes , Solventes
10.
Fresenius J Anal Chem ; 370(7): 909-12, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11569874

RESUMO

For some saline environments (e.g. deeply percolating groundwater, interstitial water in marine sediments, water sample collected after several steps of fractionation) the volume of water sample available is limited. A technique is presented which enables simultaneous determination of major and trace elements after preconcentration of only 60 mL sample on chelating resins. Chelex-100 and Chelamine were used for the preconcentration of trace elements (Cd, Cu, Pb, Zn, Sc) and rare earth elements (La, Ce, Nd, Yb) from saline water before their measurement by inductively coupled plasma mass spectrometry. Retention of the major elements (Na, Ca, Mg) by the Chelamine resin was lower than by Chelex; this enabled their direct measurement in the solution after passage through the resin column. For trace metal recoveries both resins yield the same mass balance. Only Chelex resin enabled the quantitative recovery of rare earth elements. The major elements, trace metals and rare earth elements cannot be measured after passage through one resin only. The protocol proposes the initial use of Chelamine for measurement of trace and major elements and then passage the same sample through the Chelex resin for determination of the rare earth elements. The detection limit ranged from 1 to 12 pg mL(-1). At concentrations of 1 ng mL(-1) of trace metals and REE spiked in coastal water the precision for 10 replicates was in the range of 0.3-3.4% (RSD). The accuracy of the method was demonstrated by analyzing two standard reference waters, SLRS-3 and CASS-3.


Assuntos
Espectrometria de Massas/métodos , Resinas Vegetais/química , Cloreto de Sódio/química , Oligoelementos/análise , Soluções Tampão , Quelantes/química
11.
Water Res ; 35(10): 2429-34, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11394777

RESUMO

In this paper an experimental approach of aggregation in natural suspensions is presented. The suspensions are organic-matter-rich waters sampled in a brook which drains peat areas. The aggregation was conducted on raw samples in three different experiments lasting from 2 to 8 days. The particle size distribution (PSD) in the 0.5-10 microm size range was followed with a laser sizer and appeared to be almost constant along the whole experiment duration. Nevertheless, the volume of particles larger than 10 microm increased steadily, showing that aggregation occured. This appeared to be the consequence of a steady-state aggregation which allowed the removal of the whole particle set within a day. The use of an aggregation model adapted to calculations on PSD allowed estimation of the aggregation efficiency for such suspensions.


Assuntos
Água Doce/análise , Sedimentos Geológicos/análise , Suspensões/análise , Precipitação Química , Densitometria , Filtração , Água Doce/química , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Modelos Químicos , Tamanho da Partícula , Suspensões/química , Fatores de Tempo
12.
Cancer Res ; 61(10): 4272-7, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11358855

RESUMO

157Gd is a potential agent for neutron capture cancer therapy (GdNCT). We directly observed the microdistribution of Gd in cultured human glioblastoma cells exposed to Gd-diethylenetriaminepentaacetic acid (Gd-DTPA). We demonstrated, with three independent techniques, that Gd-DTPA penetrates the plasma membrane, and we observed no deleterious effect on cell survival. A systematic microchemical analysis revealed a higher Gd accumulation in cell nuclei compared with cytoplasm. This is significant for prospective GdNCT because the proximity of Gd to DNA increases the cell-killing potential of the short-range, high-energy electrons emitted during the neutron capture reaction. We also exposed Gd-containing cells to thermal neutrons and demonstrated the GdNC reaction effectiveness in inducing cell death. These results in vitro stimulated in vivo Gd-DTPA uptake studies, currently underway, in human glioblastoma patients.


Assuntos
Gadolínio/farmacocinética , Gadolínio/uso terapêutico , Glioblastoma/metabolismo , Glioblastoma/radioterapia , Terapia por Captura de Nêutron , Morte Celular/efeitos da radiação , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Gadolínio DTPA/farmacocinética , Gadolínio DTPA/toxicidade , Humanos , Isótopos , Espectrometria de Massas , Espectrometria por Raios X , Células Tumorais Cultivadas
13.
Rapid Commun Mass Spectrom ; 15(6): 393-400, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11291116

RESUMO

A sensitive and specific analytical procedure for determining arylphenoxypropionic herbicides in soil samples, using Ionspray ionization (ISI) liquid chromatography/mass spectrometry (LC/MS), is presented. Arylphenoxypropionic acids are a new class of herbicides used for selective removal of most grass species from any non-grass crop, commercialized as herbicide esters. Previous studies have shown that the esters undergo fast hydrolysis in the presence of vegetable tissues and soil bacteria, yelding the corresponding free acid. The feasibility of rapidly extracting arylphenoxypropionic herbicides from soil by accelerated solvent extraction (ASE) techniques was evaluated. Four different soil samples were fortified with target compounds at levels of 5 and 20 ng/g by following a procedure able to mimic weathered soils. Herbicides were extracted by a methanol/water (80:20 v/v) solution (0.12 M) of NaCl at 90 degrees C. After clean-up using graphitized carbon black (GCB) as absorbent, the extract was analyzed by HPLC/ISI-MS. The effect of concentration of acid in the mobile phase on the response of ISI-MS was investigated. The effects of varying the orifice plate voltage on the production of diagnostic fragment ions, and on the response of the MS detector, were also investigated. The ISI-MS response was linearly related to the amounts of analytes injected between 1 and 200 ng. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides in soil samples was estimated to be less than 1 ng/g.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/análise , Espectrometria de Massas/métodos , Poluentes do Solo/análise , Solventes/química , Ácidos , Cromatografia Líquida de Alta Pressão/normas , Herbicidas/química , Herbicidas/isolamento & purificação , Espectrometria de Massas/normas , Poaceae , Sensibilidade e Especificidade , Poluentes do Solo/isolamento & purificação
14.
J Chromatogr A ; 874(2): 187-98, 2000 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-10817357

RESUMO

In this work we developed a sensitive and specific multiresidue method, based on reversed-phase liquid chromatography-mass spectrometry, with an ionspray interface (LC-ISI-MS), for determining 52 of most representative compounds of herbicides in water samples. The procedure used involved passing 0.5 l of surface water, 2 l of ground water and 4 l of drinking water samples, respectively, through a 0.5 g graphitized carbon black (GCB) extraction cartridge. Base-neutral and acid herbicides were differential eluted from GCB cartridge and follow analyzed by HPLC-ISI-MS apparatus. A conventional 4.6-mm-ID reversed-phase LC C18 column, operating with a mobile phase flow-rate of 1 ml/min, was used to chromatograph the analytes. A flow of 100 microl/min of the column effluent was diverted to the ISI source. The study demonstrates the sensitivity of the technique, with detection limit under 10 ng/l in drinking water samples. Performance data for the method such as recovery and precision are also reported.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Herbicidas/análise , Espectrometria de Massas/métodos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
J Chromatogr A ; 813(2): 285-97, 1998 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-9700928

RESUMO

A very sensitive and specific analytical procedure for determining arylphenoxypropionic herbicides in aqueous environmental samples, using pneumatically assisted electrospray (ESI) liquid chromatography-mass spectrometry (LC-MS) is presented. Arylphenoxypropionic acids are a new class of herbicides used for the selective removal of most grass species from any nongrass crop. These herbicides are commercialized as herbicide esters. It has been shown that the ester derivatives undergo fast hydrolysis in the presence of vegetable tissues and soil bacteria, yielding the corresponding free acid. The analytical procedure involves passing 1l of surface or ground water and 2l of drinking-water samples, through a 0.5-g graphitized carbon black (GCB) extraction cartridge. A conventional 4.6-mm I.D. reversed-phase LC C18, operating with a 1 ml/min mobile phase flow-rate, was used for chromatographing the analytes. A flow of 200 microliters/min of the column effluent was diverted to the ESI source. The ESI source was operated in positive-ion mode for neutral pesticides and in negative-ion mode for acid pesticides. For ion-signal optimization, the effect of the concentration of the acid in the mobile phase on the response of the ESI-MS detector was investigated. By evaluating the specificity and sensitivity of the method, the effects of varying the orifice plate voltage on the production of the diagnostic fragment and the response of the MS detector were also investigated. For the analyte considered, the response of the mass detector was linearly related to the amount of the analyte injected between 1 and 200 ng. In all cases, recoveries of the analytes were better than 91%. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides considered in drinking water samples was estimated to be about 3-10 ng/l.


Assuntos
Herbicidas/análise , Abastecimento de Água/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Indicadores e Reagentes , Espectrometria de Massas , Soluções
17.
Neurosci Lett ; 248(1): 9-12, 1998 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-9665651

RESUMO

We quantified the effect of the excitatory amino acids kainate and glutamate on the uptake of cobalt in primary rat cerebellar granule neurons, by using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). We quantitatively demonstrated that Co2+ uptake, although enhanced by glutamate and kainate also takes place in the absence of excitatory amino acids. We also found that cobalt uptake is not significantly altered by the presence of glutamate receptor competitive or noncompetitive antagonists, indicating that cobalt uptake in granule neurons does not require glutamate receptor stimulation. Our results suggest, therefore, that Co2+ may enter the cell by passive diffusion through the plasma membrane.


Assuntos
Cerebelo/metabolismo , Cobalto/metabolismo , Aminoácidos Excitatórios/farmacologia , Animais , Células Cultivadas , Cerebelo/citologia , Cerebelo/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Ácido Caínico/farmacologia , Ratos , Espectrometria por Raios X
18.
J Chromatogr A ; 800(1): 109-19, 1998 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-9561758

RESUMO

An evaluation was made of the feasibility of using reversed-phase liquid chromatography-mass spectrometry with an electrospray interface (LC-ESI-MS) to measure traces of imidazolinone herbicides in different natural water samples. The imidazolinones are a significant new class of low-use-rate, reduced-environmental-risk herbicides for the protection of a wide variety of agricultural commodities. The procedure used involved passing 0.5, 1, 2 1 of river, ground and drinking water samples, respectively, through a 0.5 g graphitized carbon black (GCB) extraction cartridge. Analytes were eluted from the GCB surface by 8 ml of a methylene chloride-methanol (80:20, v/v) solution acidified with formic acid, 25 mM. Recovery was higher than 89% irrespective of the aqueous matrix in which the analytes were dissolved. A conventional 4.6 mm I.D. reversed-phase LC C18 column operating with a mobile phase flow-rate of 1 ml/min was used to chromatograph the analytes. A flow of 50 microliters/min of the column effluent was diverted to the ESI source. The effects of acid concentration on ESI-MS detector response in the mobile phase were investigated. The effects on the production of diagnostic fragments produced by varying the orifice plate voltage and the response of the MS detector were also evaluated. For the analyte considered, the response of the mass detector was linearly related to the amount of analyte injected between 1 and 50 ng. The limit of detection (signal-to-noise ratio = 3) of the method for the pesticides considered in drinking water samples was estimated to be about 2-5 ng/l.


Assuntos
Cromatografia Líquida/métodos , Água Doce/química , Herbicidas/análise , Imidazóis/análise , Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análise , Herbicidas/química , Imidazóis/química , Niacina/análogos & derivados , Niacina/análise , Niacina/química , Ácidos Nicotínicos/análise , Ácidos Nicotínicos/química , Resíduos de Praguicidas/química , Quinolinas/análise , Quinolinas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Ann Fr Anesth Reanim ; 15(8): 1193-5, 1996.
Artigo em Francês | MEDLINE | ID: mdl-9636792

RESUMO

A young woman without remarkable medical history, experienced a life threatening anaphylactoid reaction after induction of general anaesthesia for an emergency curettage. Hypersensitivity reaction involving IgE antibodies against suxamethonium was proven by positive skin test and detection of specific IgE by radio-immuno assay. After intensive therapy for 2 to 3 hours, the patient exhibited rhabdomyolysis localized on both calves. This complication, which required fasciotomies, did not result in renal failure. Local and general outcome was good. Rhabdomyolysis was due to compartmental ischaemia following shock and local external compression in the lithotomy position.


Assuntos
Anafilaxia/etiologia , Fármacos Neuromusculares Despolarizantes/efeitos adversos , Rabdomiólise/induzido quimicamente , Succinilcolina/efeitos adversos , Adulto , Anafilaxia/complicações , Desbridamento , Feminino , Humanos , Perna (Membro)/cirurgia , Rabdomiólise/terapia , Testes Cutâneos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...