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1.
J Orofac Orthop ; 81(4): 267-285, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32556368

RESUMEN

PURPOSE: To systematically search the scientific literature concerning the influence of playing a wind instrument on tooth position and/or facial morphology. METHODS: The PubMed, EMBASE and Cochrane databases were searched up to September 2019. Orthodontic journals were hand searched and grey literature was sought via Google Scholar. Observational studies and (randomized) controlled clinical trials that assessed tooth position and/or facial morphology by profile cephalograms, dental casts or clinical examination were included. The potential risk of bias was assessed. Data from wind instrument players and controls were extracted. Descriptive analysis and meta-analysis were performed. RESULTS: In total, 10 eligible studies with a cross-sectional (n = 7) or longitudinal design (n = 3) and an estimated low to serious risk of bias were included. Sample sizes ranged from 36 to 170 participants, varying from children to professional musicians. Descriptive analysis indicated that adults playing a single-reed instrument may have a larger overjet than controls. Playing a brass instrument might be associated with an increase in maxillary and mandibular intermolar width among children. Longitudinal data showed less increase in anterior facial height among brass and single-reed players between the age of 6 and 15. Children playing a wind instrument showed thicker lips than controls. Meta-analysis revealed that after a follow-up of 6 months to 3 years, children playing brass instruments had a significant reduction in overjet as compared to controls. The magnitude of the effect was of questionable clinical relevance and the generalizability was limited. CONCLUSIONS: Playing a wind instrument can influence tooth position and facial morphology in both children and adults. Aspects that stand out are overjet, arch width, facial divergence/convergence and lip thickness. However, evidence was sparse and the strength of the premise emerging from this review was graded to be "very low".


Asunto(s)
Música , Sobremordida , Diente , Adulto , Niño , Estudios Transversales , Cara , Humanos
2.
Int J Dent Hyg ; 16(1): 24-35, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28573755

RESUMEN

OBJECTIVE: The aim of this systematic review was to assess the effect of a whitening dentifrice (WDF) relative to a regular dentifrice (RDF) on the reduction of natural extrinsic tooth surface discoloration (ETD). MATERIALS AND METHODS: The MEDLINE-PubMed, Cochrane-CENTRAL and EBSCO-Dentistry and Oral Sciences databases were searched, up to April 2017. The inclusion criteria were as follows:(randomized)controlled clinical trials, healthy subjects ≥18 years of age, studies comparing WDF with RDF, a follow-up period of at least 6 weeks and studies scoring ETD as the stain area/extent, stain intensity or a composite score. Studies using an induced staining model were excluded. RESULTS: Independent screening of 851 unique papers resulted in 21 eligible publications, which included 32 comparisons. The descriptive analysis illustrated that the majority of comparisons showed a significant effect on ETD, in favour of WDF over RDF. The meta-analysis substantiated this observation and revealed that the difference of means (diffM) comparing WDF and RDF was a reduction for stain area of -0.44 [(95% CI: -0.55; -0.339) (P<.00001)] according to the original Lobene Stain Index; this result is in favour of the WDF. For the modified Lobene Stain Index, the diffM was -0.41 [(95% CI: -0.71; -0.10) (P=.009)]. For overall stain intensity, the diffM was -0.35 [(95% CI: -0.44; -0.25) (P<.00001)], and the composite score was -0.39 [(95% CI: -0.57; -0.21) (P<.0001)] and -0.54 [(95% CI: -0.66; -0.43) (P<.00001)]. Subgroup analysis differentiating between products that contained added chemical antidiscoloration agents showed a similar pattern. CONCLUSION: In this review, nearly all dentifrices that are specifically formulated for tooth whitening were shown to have a beneficial effect in reducing ETD, irrespective of whether or not a chemical discoloration agent was added.


Asunto(s)
Dentífricos , Blanqueadores Dentales , Blanqueamiento de Dientes , Decoloración de Dientes/prevención & control , Humanos
3.
J Chromatogr B Biomed Sci Appl ; 691(1): 145-53, 1997 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-9140768

RESUMEN

An analytical method for the determination of artemether (A) and its metabolite dihydroartemisinin (DHA) in human plasma has been developed and validated. The method is based on high-performance liquid chromatography (HPLC) and electrochemical detection in the reductive mode. A, DHA and artemisinin, the internal standard (I.S.), were extracted from plasma (1 ml) with 1-chlorobutane-isooctane (55:45, v/v). The solvent was transferred, evaporated to dryness under nitrogen and the residue dissolved in 600 microliters of water-ethyl alcohol (50:50, v/v). Chromatography was performed on a Nova-Pak CN, 4 microns analytical column (150 mm x 3.9 mm I.D.) at 35 degrees C. The mobile phase consisted of pH 5 acetate-acetonitrile (85:15, v/v) at a flow-rate of 1 ml/min. The analytes were detected by electrochemical detection in the reductive mode at a potential of -1.0 V. Intra-day accuracy and precision were assessed from the relative recoveries (found concentration in % of the nominal value) of spiked samples analysed on the same day (concentration range 10.9 to 202 ng/ml of A and 11.2 to 206 ng/ml of DHA in plasma). The mean recoveries over the entire concentration range were from 96 to 100% for A with C.V. from 6 to 13%, from 92% to 100% for DHA (alpha-tautomer) with C.V. from 4 to 16%. For A, the mean recovery was 96% at the limit of quantitation (LOQ) of 10.9 ng/ml with a C.V. of 13%. For DHA, the mean recovery was 100% at the LOQ of 11.2 ng/ml with a C.V. of 16%.


Asunto(s)
Antimaláricos/sangre , Artemisininas , Cromatografía Líquida de Alta Presión/métodos , Sesquiterpenos/sangre , Acetatos , Acetonitrilos , Arteméter , Autoanálisis , Cromatografía Líquida de Alta Presión/estadística & datos numéricos , Estabilidad de Medicamentos , Humanos , Control de Calidad , Sensibilidad y Especificidad
4.
Mutat Res ; 307(1): 61-6, 1994 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-7513825

RESUMEN

A methodology is described for the quantitation of 7-alkyl- and O6-alkylguanine in DNA isolated from experimental animals exposed to alkylating agents. Following purification, the DNA is hydrolysed under acid conditions after which 7-alkyl- and O6-alkylguanine are separated from unmodified bases by HPLC using a strong cation exchange column. The fractions containing the methylated purines are subsequently analyzed by HPLC using a reverse phase column coupled to an electrochemical detector (amperometric). This method allows the detection of 10-20 fmoles 7-alkyl- and O6-alkylguanine, when pure markers are analyzed. In practice, the detection limit is 0.5 adducts per 10(6) nucleotides for the methylated and 1 adduct per 10(6) nucleotides for the ethylated form of 7-alkyl- and O6-alkylguanine using 25 micrograms DNA.


Asunto(s)
ADN/química , Guanina/análogos & derivados , Alquilantes/farmacología , Animales , Cromatografía Líquida de Alta Presión , ADN/efectos de los fármacos , ADN/aislamiento & purificación , Electroquímica , Guanina/análisis
5.
Int J Rad Appl Instrum B ; 19(7): 759-63, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1399697

RESUMEN

Radioiodinated spiperone is of interest for dopamine (DA) receptor studies in the living human brain by single photon emission computed tomography (SPECT). Stimulated by data obtained with [11C]-N-methyl-spiperone we synthesized 4-[123I]iodospiperone and investigated the in vitro binding characteristics of this ligand to the striatal membrane of the rat and the in vivo distribution over various rat brain regions. The in vitro binding experiments showed that this radioligand displays about 10 times less affinity for the DA receptor than spiperone and specific binding, as shown with [3H]spiperone, was not observed. Displacement by butaclamol was not observed. The in vivo studies demonstrated that both 4-[123I]iodospiperone and [3H]spiperone concentrate in striatal tissue, respectively, 1.9 and 3.5 times as high as in cerebellar tissue. Haloperidol pretreatment largely prevented this accumulation. In view of the obtained target-to-non-target ratios we believe, however, that this accumulation in brain areas rich in DA-receptors does not offer prospects for clinical receptor imaging with SPECT.


Asunto(s)
Encéfalo/metabolismo , Cuerpo Estriado/metabolismo , Radioisótopos de Yodo , Receptores Dopaminérgicos/metabolismo , Espiperona/análogos & derivados , Espiperona/metabolismo , Animales , Unión Competitiva , Membrana Celular/metabolismo , Masculino , Especificidad de Órganos , Ratas , Ratas Wistar , Receptores Dopaminérgicos/análisis , Tritio
6.
Histochem J ; 22(6-7): 353-7, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1698751

RESUMEN

The fixation of the neurotransmitter dopamine in the central nervous system by perfusion with formalin solutions seems to take place mainly via the formalin-induced condensation product norsalsolinol. In the present investigation the influence of microwave irradiation of the formalin-induced condensation of dopamine was studied in vitro and in vivo by making use of different, relatively low, formalin concentrations. It appeared that in vitro and in vivo the dopamine conversion was complete with 4% formalin and no influence of microwaves was noted. However, by making use of much lower formalin concentrations (0.2% and 0.4%) the condensation of dopamine was strongly augmented, in vitro (200%) and in vivo (at least 500%) using microwave techniques. There was a considerable loss in non-microwaved tissue (30%) after perfusion in vivo. This was lower (10%) in microwaved tissue. In experiments with perfused brain tissue which allowed a more complete calculation, a loss was found. This might be caused by a strong binding of dopamine and/or norsalsolinol to tissue components or to side reactions that could not be traced by the present experimental techniques.


Asunto(s)
Encéfalo/anatomía & histología , Dopamina/química , Formaldehído , Microondas , Alcaloides de Salsolina/química , Animales , Química Encefálica , Cromatografía Liquida , Cuerpo Estriado/anatomía & histología , Dopamina/efectos de la radiación , Femenino , Ratas , Ratas Endogámicas , Alcaloides de Salsolina/efectos de la radiación , Coloración y Etiquetado
7.
Eur J Pharmacol ; 158(1-2): 29-35, 1988 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-3220118

RESUMEN

Repeated administration of 1-hydroxy-3-amino-pyrrolidone-2 (HA-966) to rats induces tolerance, as shown by a decreased, drug-stimulated accumulation of dopamine (DA) in the striatum. In the present study we compared the adaptive response of the striatal dopaminergic system to repeated administration of HA-966 with the adaptive response observed after repeated haloperidol. These treatments deprive dopamine (DA) receptors from their agonist and cause a blockade of DA receptors, respectively. Tolerance to HA-966 was not accompanied by a change in the specific binding of [3H]spiperone to striatal membranes. This is in contrast to the well-documented up-regulation of DA receptors that occurs with tolerance to haloperidol. Repeated haloperidol pretreatment also diminished DA accumulation following a challenge dose of HA-966, to a similar extent as that caused by repeated pretreatment with HA-966. These similar effects of pretreatment with HA-966 or haloperidol on the response to the HA-966 challenge are in line with, and strengthen, the idea that an increased sensitivity of presynaptic DA receptors is responsible for the decreasing effect of HA-966 after its repeated administration. Haloperidol and HA-966 clearly have different effects on postsynaptic DA receptors, as is shown by their differential effects on striatal [3H]spiperone binding.


Asunto(s)
Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Haloperidol/administración & dosificación , Pirrolidinonas/administración & dosificación , Ácido 3,4-Dihidroxifenilacético/metabolismo , Animales , Cuerpo Estriado/metabolismo , Tolerancia a Medicamentos , Ácido Homovanílico/metabolismo , Masculino , Ratas , Ratas Endogámicas , Receptores Dopaminérgicos/efectos de los fármacos , Receptores Dopaminérgicos/metabolismo , Espiperona/metabolismo
8.
J Chromatogr ; 427(1): 9-17, 1988 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-3410905

RESUMEN

A tritium isotope effect has been demonstrated in the high-performance liquid chromatographic analysis of dopamine and its acidic metabolite dihydroxyphenylacetic acid. The chromatographic system consisted of tributyl-n-phosphate, bound to a ChromSpher C8 column, as stationary phase, and a citrate buffer, containing the ion-pairing agent perchlorate, as the mobile phase. For detection we used continuous electrochemical monitoring (for the total amount of solutes) and discontinuous liquid scintillation counting (for radiolabelled molecules) of the column effluent. [3H]Dopamine and [3H]dihydroxyphenylacetic acid were biosynthesized by incubation of homogenates of striatal tissue from rat brains with 3H-labelled L-tyrosine. The tritium-labelled compounds were eluted before the corresponding unlabelled analogues. The capacity factor reduction increased with the number of tritium atoms incorporated in the molecules: for single, double and triple tritium-labelled dopamine the separation factors amounted to 1.015, 1.028 and 1.033, respectively. No isotope separation was observed for 7-14C-labelled dopamine and dihydroxyphenylacetic acid. The isotope effect observed is ascribed to a decrease in lipophilicity following tritium substitution for hydrogen.


Asunto(s)
Ácido 3,4-Dihidroxifenilacético/análisis , Dopamina/análisis , Fenilacetatos/análisis , Animales , Cromatografía Líquida de Alta Presión , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Electroquímica , Técnicas In Vitro , Marcaje Isotópico , Masculino , Ratas , Ratas Endogámicas , Tritio
9.
Neurochem Int ; 12(2): 203-8, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-20501222

RESUMEN

It is still a matter of debate whether in dopaminergic nerve endings dopamine (DA) is present in different functional and/or metabolic compartments. To investigate this, DA metabolism was studied in vivo by measuring the specific activity of DA and its metabolites after intravenous administration of l-[3,5-(3)H]tyrosine (200 ?Ci/rat) to freely moving animals. The incorporation of (3)H into DA and metabolites was determined in striatum and olfactory tubercle at 5, 10, 20, 40, 60 and 80 min after [(3)H]tyrosine administration. In both structures the level of [(3)H]tyrosine initially declined monoexponentially, but deviated from that pattern later on. The curves representing the formation in time of [(3)H]DA and [(3)H]metabolites were very similar in both structures, although as a whole, the levels in the olfactory tubercle were higher. The relative patterns of the specific activities of DA and those of its metabolites, a possible clue to DA compartmentation, neither indicated a clearcut metabolic one-compartment, nor a two-compartment system. The flow of radioactivity through DA metabolism could in fact only be explained by assuming more complex metabolic relations.

10.
Am J Psychiatry ; 143(11): 1443-6, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3777238

RESUMEN

The authors performed structured psychiatric examinations of 188 former prisoners of war (POWs). Sixty-seven percent had had posttraumatic stress disorder. Of those affected, 29% had fully recovered, 39% still reported mild symptoms, 24% had improved but had moderate residual symptoms, and 8% had had no recovery or had deteriorated. Presence of posttraumatic stress disorder was not significantly correlated with other mental disorders. Delayed onset was not seen. The findings confirm the DSM-III concept of and criteria for posttraumatic stress disorder.


Asunto(s)
Prisioneros , Trastornos por Estrés Postraumático/diagnóstico , Guerra , Enfermedad Crónica , Estudios de Seguimiento , Humanos , Masculino , Trastornos Mentales/diagnóstico , Trastornos Mentales/epidemiología , Minnesota , Inventario de Personalidad , Escalas de Valoración Psiquiátrica , Trastornos por Estrés Postraumático/epidemiología
11.
Am J Psychiatry ; 143(6): 718-22, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3717392

RESUMEN

The authors examined the association of antisocial personality disorder, somatization disorder, and histrionic personality disorder, both within individuals and within families, in 250 patients. All three disorders overlapped considerably within individuals; the strongest relationship was between antisocial personality and histrionic personality. A high prevalence of antisocial personality was reported in the families of patients with somatization disorder but not in the families of patients with histrionic personality. The authors suggest that histrionic individuals develop antisocial personality if they are male and somatization disorder if female; moreover, all three conditions may represent alternative manifestations or different stages of the same underlying diathesis.


Asunto(s)
Trastorno de Personalidad Antisocial/complicaciones , Trastorno de Personalidad Histriónica/complicaciones , Trastornos Somatomorfos/complicaciones , Trastorno de Personalidad Antisocial/genética , Femenino , Trastorno de Personalidad Histriónica/genética , Humanos , Masculino , Factores Sexuales , Trastornos Somatomorfos/genética
13.
Naunyn Schmiedebergs Arch Pharmacol ; 327(3): 208-13, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6493361

RESUMEN

Administration of morphine results in efflux of dopamine provided that the nerve impulse flow of the dopaminergic neurones is impaired. In the present study we investigated whether the morphine-induced increase in dopamine metabolite levels is related to impulse flow in a similar way. Pretreatment with gamma-butyrolactone to impair nerve impulse flow, abolished the effect of morphine on the concentrations of dihydroxyphenylacetic acid and homovanillic acid. Pretreatment with apomorphine had a similar effect, as well as combined pretreatment with gamma-butyrolactone and apomorphine. Since gamma-butyrolactone and apomorphine both reduce nerve impulse flow, but gamma-butyrolactone increases while apomorphine decreases dopamine biosynthesis, it would appear that the antagonism of morphine-induced increases in dopamine metabolites is due to the common property of impulse flow reduction. It was also shown, however, that pretreatment with alpha-methyl-paratyrosine, which inhibits dopamine biosynthesis, resulted in antagonism of morphine's effect on dopamine metabolite levels. It is concluded, therefore, that morphine-induced dopamine efflux is observed under conditions when no effect on dopamine metabolism is observed, and vice versa. Three effects of morphine on dopaminergic neurones can be distinguished: an increase in impulse flow in nigrostriatal dopaminergic neurones, increased dopamine biosynthesis and catabolism, and efflux of dopamine. The first effect probably is effected in the cell body areas, while the latter two effects may be produced at the level of the nerve terminals.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Sistema Límbico/metabolismo , Morfina/farmacología , Neuronas/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , 4-Butirolactona/farmacología , Animales , Dopamina/fisiología , Ácido Homovanílico/metabolismo , Masculino , Ratas , Ratas Endogámicas
14.
J Clin Psychiatry ; 45(9): 367-9, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6469919

RESUMEN

Of a group of 288 depressed female inpatients, 43 (15%) had secondary panic attacks. Compared to other depressives, the subgroup with panic attacks had significantly higher frequencies of anorexia, weight loss, gastrointestinal disturbances, hypochondriasis, and psychomotor agitation, and significantly lower frequencies of melancholic symptoms, including loss of interest in usual activities, guilt feelings, delusional thinking, psychomotor retardation, and orientation or memory impairment. Patients with panic attacks were less likely to have a depressed parent and were more likely to be described as having been nervous, worrisome, sensitive, and sexually dysfunctional before the onset of depression. Phenomenologically, they resembled "anxious depressives" as described by other authors.


Asunto(s)
Trastornos de Ansiedad/diagnóstico , Trastorno Depresivo/diagnóstico , Miedo , Pánico , Adulto , Anorexia/psicología , Trastornos de Ansiedad/complicaciones , Trastornos de Ansiedad/psicología , Peso Corporal , Deluciones/psicología , Trastorno Depresivo/complicaciones , Trastorno Depresivo/psicología , Diagnóstico Diferencial , Femenino , Enfermedades Gastrointestinales/psicología , Culpa , Hospitalización , Humanos , Hipocondriasis/psicología , Agitación Psicomotora/psicología , Disfunciones Sexuales Psicológicas/psicología
15.
J Affect Disord ; 6(3-4): 287-95, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6235260

RESUMEN

In this clinical, psychometric and polysomnographic study, primary dysthymics (N = 20) were compared with anxious depressives (N = 22), and non-psychiatric controls (N = 11). Beck and MMPI depression scores were similar in the two affective groups. Prominent insomnia occurred in 82% of the anxious group; hypersomnia was more characteristic of the dysthymic group. On night 1, the anxious group had the poorest sleep efficiency (P less than 0.001), while dysthymics had the highest REM% (P less than 0.05) and shortest REM latency (P less than 0.01). On night 2, differences tended to be minimized, although the number of awakenings was still high (P less than 0.05) in the anxious group, and REM% was highest (P less than 0.01) and REM latency shortest (P less than 0.01) in the dysthymics. These findings suggest that patients with primary anxiety disorders experience greater sleep continuity difficulties on the adaptation night. Despite significant clinical overlap in depressive symptomatology between the two groups, REM% and REM latency appear as sturdy psychophysiological markers in differentiating primary dysthymics and anxious depressives on both nights. These data suggest that distinct anxious depressive and subaffective dysthymic subtypes can be distinguished within the universe of the atypical depressions.


Asunto(s)
Trastornos de Ansiedad/fisiopatología , Depresión/fisiopatología , Trastorno Depresivo/fisiopatología , Sueño , Adulto , Trastornos de Ansiedad/complicaciones , Depresión/etiología , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción , Sueño/fisiología , Sueño REM/fisiología
16.
J Neurosci Methods ; 11(1): 29-38, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6471906

RESUMEN

A procedure to determine the specific activities (s.a.) of the putative neurotransmitter dopamine (DA) and its metabolites in rat striatum is described. For this purpose 200 mu Ci L-[3,5-3H]tyrosine was injected via a jugular vein cannula into freely moving rats. Contents and radioactivity of striatal tyrosine, DA, 3,4-dihydroxyphenylacetic acid (DOPAC), 3-methoxytyramine (3-MT) and homovanillic acid (HVA) were determined by means of HPLC, electrochemical detection (ECD) and liquid scintillation counting. In the phase system applied DA, DOPAC, 3-MT and HVA can be separated in a single run after direct injection of striatal supernatants. The selectivity of the phase system was sufficient to analyse the supernatant of two rat striata over a 150 X 4.6 mm column, even when DA turnover was strongly stimulated. Tyrosine levels and radioactivity were measured by re-analysis of the front peak with divergent mobile phase parameters. In order to demonstrate the applicability of the present procedure, the s.a. of DA and its metabolites, as found 20 min after [3H]tyrosine administration, and the effect of haloperidol thereupon, are presented.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Ácido 3,4-Dihidroxifenilacético/metabolismo , Animales , Dopamina/análogos & derivados , Electroquímica , Ácido Homovanílico/metabolismo , Masculino , Ratas , Ratas Endogámicas , Conteo por Cintilación , Tritio , Tirosina/metabolismo
17.
J Chromatogr ; 282: 443-56, 1983 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-6201500

RESUMEN

A flexible and efficient system is described for reversed-phase ion-pair partition-chromatographic analysis of serotonin, its precursors tryptophan and 5-hydroxytryptophan, its main metabolite 5-hydroxyindoleacetic acid, and tryptamine. The chromatographic system consists of tri-n-butylphosphate as stationary phase and buffered water-methanol mixtures, containing perchlorate, as mobile phases. Retention can be selectively influenced by means of the pH, the perchlorate concentration, and the methanol content of the mobile phase, as well as the temperature of the phase system. The compounds of interest can be separated within 10 min and no interference from catecholamines and derivatives was observed. Compared with electrochemical detection, fluorometric detection yielded more favourable detection limits and was more selective when supernatants of brain tissue homogenates were directly injected. Both detection systems showed inadequate selectivity if urine samples were directly injected, but 5-hydroxyindoleacetic acid could readily be assayed.


Asunto(s)
Serotonina/análisis , Animales , Química Encefálica , Cromatografía Liquida/métodos , Cuerpo Estriado/análisis , Electroquímica , Femenino , Ácido Hidroxiindolacético/orina , Indoles/análisis , Matemática , Ratas , Ratas Endogámicas , Serotonina/orina , Espectrometría de Fluorescencia
20.
J Neurochem ; 39(4): 990-7, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6288866

RESUMEN

A method, based on reverse-phase liquid-liquid chromatography, has been developed for the determination, in a single run, of dopamine (DA) and its acidic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), combined with electrochemical detection (ECD). If applied to brain tissue, sample pretreatment can be reduced to centrifugation, filtration and adjustment of pH and perchlorate concentration prior to introduction into the liquid chromatograph. The relation between the perchlorate (counterion) concentration of the mobile phase and the retention (k') of the amines is linear, as is the relation between the H+ concentration of the mobile phase and the retention of the acidic metabolites. This flexible phase system, combined with a simple and therefore reproducible sample pretreatment, warrants a high throughput of samples. The procedure offers good possibilities for routine analysis of catecholamines and their acidic metabolites in the picogram range. Some typical examples of the behaviour of this phase system and the electrochemical detector are presented and discussed.


Asunto(s)
Química Encefálica , Dopamina/análisis , Animales , Cromatografía Líquida de Alta Presión/instrumentación , Femenino , Concentración de Iones de Hidrógeno , Percloratos , Ratas , Ratas Endogámicas
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