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1.
Kyobu Geka ; 64(4): 305-10, 2011 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-21491726

RESUMO

Thoracoscopic surgery under epidural and local anesthesia for intractable pneumothorax were performed in 26 patients. A total of 29 thoracoscopic operation were performed in 26 patients. Twenty-three patients undervent only a single thoracoscopic operation, and 3 patients underwent twice thoracoscopic operations. We could control the air leak of intractable pneumothorax with the covering of polyglycolic acid sheets using aerosolized fibrin glue in 25 patients. In all patients postoperative course was uneventful and there was no operative death.


Assuntos
Anestesia Epidural , Anestesia Local , Pneumotórax/cirurgia , Toracoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Adesivo Tecidual de Fibrina , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Poliglicólico
3.
Chemosphere ; 69(4): 585-94, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17459453

RESUMO

Evaporation basins (or ponds) are the most commonly used facilities for disposal of selenium-laden saline agricultural drainage in the closed hydrologic basin portion of the San Joaquin Valley, California. However concerns remain for potential risk from selenium (Se) toxicity to water fowl in these evaporation basins. In this study, we examined the chemical status of Se in both waters and sediments in two currently operating evaporation pond facilities in the Tulare Lake Drainage District. Some of the saline ponds have been colonized by brine-shrimp (Artemia), which have been harvested since 2001. We evaluated Se concentration and speciation, including selenate [Se(VI)], selenite [Se(IV)], and organic Se [org-Se or Se(-II)] in waters and sediment extracts, and fractionation (soluble, adsorbed, organic matter (OM)-associated, and Se(0) and other resistant forms) in sediments and organic-rich surface detrital layers from the decay of algal blooms. Selenium in ponds without vascular plants exhibited similar behavior to wetlands with vascular plant present, indicating that similar Se transformation processes and mechanisms had resulted in Se immobilization and an increase of reduced Se species [Se(IV), org-Se, and Se(0)] from Se(VI)-dominated input waters. Selenium concentrations in most pond waters were significantly lower than the influent drainage water. This decrease of dissolved Se concentration was accompanied by the increase of reduced Se species. Selenium accumulated preferentially in sediments of the initial pond cell receiving drainage water. Brine-shrimp harvesting activities did not affect Se speciation but may have reduced Se accumulation in surface detrital and sediments.


Assuntos
Agricultura , Compostos de Selênio/análise , Selênio/análise , Selenito de Sódio/análise , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Adsorção , Animais , Aquicultura , Artemia , Sedimentos Geológicos/análise , Ácido Selênico
4.
Phytochemistry ; 57(2): 209-21, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11382236

RESUMO

Root exudates released into soil have important functions in mobilizing metal micronutrients and for causing selective enrichment of plant beneficial soil micro-organisms that colonize the rhizosphere. Analysis of plant root exudates typically has involved chromatographic methods that rely on a priori knowledge of which compounds might be present. In the research reported here, the combination of multinuclear and 2-D NMR with GC-MS and high-resolution MS provided de novo identification of a number of components directly in crude root exudates of different plant types. This approach was applied to examine the role of exudate metal ion ligands (MIL) in the acquisition of Cd and transition metals by barley and wheat. The exudation of mugineic acids and malate was enhanced by Fe deficiency. which in turn led to an increase in the tissue content of Cu, Mn, and Zn. The presence of elevated Cd maintained at a free activity pCd of 8.8 (10(-8.8) M), resulted in reduced phytosiderophore production by Fe deficient plants. The buffer morpholinoethane sulfonate (MES), which is commonly used in chelator-buffering nutrient solutions, was detected in the root exudate mixture, suggesting uptake and re-secretion of this compound by the roots. The ability to detect this compound in complex mixtures containing organic acids, amino acids, and other substances suggests that the analytical methods used here provide an unbiased method for simultaneous detection of all major components contained in root exudates.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/análise , Raízes de Plantas/química
5.
J Lipid Res ; 35(4): 678-89, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8006523

RESUMO

Lipid composition of body fat can be a key indicator of nutritional status and a number of human disorders. In vivo 13C NMR provides for repeated, noninvasive analysis of fatty acyl chain composition on individuals, which circumvents classical problems of individual variation and repetitive invasive sampling. It also offers a unique opportunity to examine acyl chain organization in situ. This approach was used to examine the fatty acyl chain composition in the perirenal fat pads of rats fed olive, safflower, and menhaden oil-containing diets. These changes were then monitored during a diet switch between olive and menhaden oil-fed rats. The fatty acid composition of perirenal fat pads and livers was also analyzed using gas chromatography for comparison with the in vivo NMR analysis. Both tissues assumed the general characteristics of diet fatty acyl chain and fatty acid composition and the diet switch induced a switchover of the perirenal composition in 30-45 days. These results indicate that a large portion of the diet fatty acyl chains were incorporated directly into adipose and liver tissues although some were also metabolized, particularly in menhaden oil-fed rats. Furthermore, changes in the in vivo spin-lattice relaxation times (T1) of fatty acyl carbons in the perirenal fat pads and their lipid extracts were followed and effective correlation times (tau eff) were calculated from the T1 data. The result indicated that the in vivo segmental mobility of acyl carbons was sensitive to changes in diet-derived fatty acyl chain composition and that the central region of the acyl chain was more sensitive to these changes. There was a qualitative similarity but quantitative differences in the tau eff of acyl carbons acquired in vivo and from extracts. These results suggest that adipose triacylglycerides experience an overall liquid-like microenvironment in vivo but with more restriction in their mobility, and that different factors may exist in governing their organization in situ versus in extracts.


Assuntos
Tecido Adiposo/química , Gorduras na Dieta/metabolismo , Óleos de Peixe/metabolismo , Óleos de Plantas/metabolismo , Triglicerídeos/química , Animais , Cromatografia Gasosa , Ácidos Graxos/análise , Rim , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley , Triglicerídeos/análise
6.
Biochim Biophys Acta ; 1135(1): 44-9, 1992 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-1591272

RESUMO

We have employed the driven 31P-NMR saturation transfer method to measure in vivo the temperature dependence of the forward and reverse unidirectional fluxes of the arginine kinase reaction in the tail muscle of a live shrimp, Sycionia ingentis. Our results indicated that neither the forward nor the reverse rate constants of this reaction were significantly temperature-dependent between 8 and 16 degrees C, in contrast to the kinetic characteristics of isolated arginine kinases.


Assuntos
Arginina Quinase/metabolismo , Músculos/enzimologia , Trifosfato de Adenosina/metabolismo , Animais , Crustáceos , Cinética , Espectroscopia de Ressonância Magnética/métodos , Modelos Teóricos , Fósforo , Temperatura
7.
Biochim Biophys Acta ; 1092(1): 39-47, 1991 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-2009311

RESUMO

We employed surface probe-localized 31P-NMR spectroscopy to examine in situ the impact of short-term emergence (hypoxia) and resubmergence on phosphate metabolites and intracellular pH (pHi) in intact mussels. The use of intact organisms ensured that all intrinsic responses remained active while monitoring of individuals minimized uncertainties resulting from stochastic behavior and other individual differences. The use of a photoetched, balanced-match foil probe combined with 1H-NMR images allowed 31P-NMR spectra to be acquired from the posterior adductor muscle with good signal-to-noise. Upon emergence, all mussels exhibited an increase in [Pi], a decline in [phosphoarginine] and pHi, and very little changes in [ATP] with time. The complementary behavior of [phosphoarginine] and [Pi] indicated a precursor-product relationship involved in the maintenance of [ATP] but the similarity between [phosphoarginine] and pHi time-courses cannot be so readily explained. Irregularity in the time-courses of some parameters could have reflected stochastic gaping activity. Resubmergence responses exhibited a reversal of the emergence responses, except that the pHi eventually became supraalkaline with irregular fluctuations. This might be related to the 'oxygen debt' phenomenon and increased oxidative phosphorylation.


Assuntos
Bivalves/metabolismo , Fosfatos/metabolismo , Adaptação Fisiológica , Animais , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos
8.
J Biochem Toxicol ; 6(1): 45-56, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1880788

RESUMO

The sublethal biochemical effects of pentachlorophenol (PCP) were investigated in live, intact red abalones (Haliotis rufescens), using a flow-through exposure system, by in vivo 31P NMR spectroscopy. Based on rangefinding tests (6-hr LC50 = 1.6 mg/L; 6-hr no-observable-effect-level (NOEL) = 0.8 mg/L), three abalones were separately exposed to a sublethal concentration (1.2 mg/L) for 5 hr, followed by a 13 hr recovery period. Effects in foot muscle included both a decrease in phosphoarginine and an increase in inorganic monophosphate concentrations ([PA] and [Pi], respectively); both foot muscle concentrations of adenosine triphosphate [ATP] and intracellular pH (pHi) also declined. Parallel in vitro experiments revealed that concentrations of glycerol 3-phosphate, lactate, citrate, succinate, malate, and alanine (Ala) all increased, while those of glyceraldehyde 3-phosphate and glutamine (Gln) remained stable. Also, these effects were not evident until 2 hr into exposure, possibly the time required for PCP to attain an effective concentration in foot muscle. During recovery, while Pi declined to pre-exposure levels, [PA] completely recovered in only one individual. Also, realkalinization of pHi was similar to recovery of [Pi], and ATP returned to near-initial levels, as did glycerol 3-phosphate, lactate, succinate, malate, and Ala; glyceraldehyde 3-phosphate, citrate, and Gln levels declined. Recovery responses corresponded to the time for PCP clearance from foot muscle. The effects of PCP were similar to those of hypoxia, fatigue, hypersalinity, and arginine kinase inhibitors, and so sublethal PCP concentrations may also inhibit electron transport and arginine kinase as well as uncouple mitochondrial oxidative phosphorylation in intact molluscs. Thus, the effects of pollutants on key biochemical processes may now be measured in intact aquatic organisms as they occur, improving our ability to accurately assess the environmental effects of pollutants in the laboratory.


Assuntos
Crustáceos/metabolismo , Pentaclorofenol/toxicidade , Animais , Espectroscopia de Ressonância Magnética/métodos , Músculos/metabolismo , Pentaclorofenol/farmacocinética , Fosfatos/metabolismo , Fósforo , Fosforilação , Distribuição Tecidual
9.
Proc Natl Acad Sci U S A ; 86(24): 9856-60, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2557632

RESUMO

A Na+ uptake-associated vacuolar alkalinization was observed in roots of two barley cultivars (Arivat and the more salt-tolerant California Mariout) by using 23Na and 31P in vivo NMR spectroscopy. A NaCl uptake-associated broadening was also noted for both vacuolar Pi and intracellular Na NMR peaks, consistent with Na+ uptake into the same compartment as the vacuolar Pi. A close coupling of Na+ with H+ transport (presumably the Na+/H+ antiport) in vivo was evidenced by qualitative and quantitative correlations between Na+ accumulation and vacuolar alkalinization for both cultivars. Prolongation of the low NaCl pretreatment (30 mM) increased the activity of the putative antiport in Arivat but reduced it in California Mariout. This putative antiport also showed a dependence on NaCl concentration for California Mariout but not for Arivat. No cytoplasmic acidification accompanied the antiporter activity for either cultivar. The response of adenosine phosphates indicated that ATP utilization exceeded the capacity for ATP synthesis in Arivat, but the two processes seemed balanced in California Mariout. These comparisons provide clues to the role of the tonoplast Na+/H+ antiport and compensatory cytoplasmic adjustments including pH, osmolytes, and energy phosphates in governing the different salt tolerance of the two cultivars.


Assuntos
Proteínas de Transporte/metabolismo , Plantas/metabolismo , Sódio/metabolismo , Nucleotídeos de Adenina/metabolismo , Hordeum/metabolismo , Cinética , Espectroscopia de Ressonância Magnética/métodos , Fósforo , Cloreto de Sódio/metabolismo , Trocadores de Sódio-Hidrogênio
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