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1.
Brain Dev ; 46(5): 207-212, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38448301

RESUMO

BACKGROUND AND OBJECTIVES: Niemann-Pick type C (NPC) is a rare lysosomal storage disease characterized by hepatosplenomegaly and progressive neurological deterioration due to abnormal intracellular cholesterol transport. Cyclic oligosaccharide 2-hydroxypropyl-ß-cyclodextrin (HPBCD) is an effective treatment for NPC; however, few reports have shown its long-term efficacy and safety. To demonstrate long-term efficacy and safety of intrathecal HPBCD (IT-HPBCD) treatment for NPC, we herein reports five patients with NPC treated using IT-HPBCD for 4-11 years. CASES AND RESULTS: Patients' ages at the onset ranged from 1.5 to 20 years. Notably, all patients showed rapid disease progression despite treatment with miglustat before IT-HPBCD treatment. Similarly, some patients showed transient improvement; however, all patients' conditions stabilized after long-term IT-HPBCD therapy. Mild-to-moderate hearing loss was observed in three patients. Furthermore, long-term treatment with IT-HPBCD may suppress neurological deterioration in patients with NPC; however, patients still experience some disease progression. CONCLUSIONS: Long-term treatment with IT-HPBCD may suppress neurological deterioration in patients with NPC; however, the treatment outcome is dependent on the neurological status at the time of diagnosis, and disease progression is not completely inhibited. Awareness of the disease and newborn screening is needed for earlier disease detection. In addition, further optimization of the treatment protocol and additional treatments are needed to improve patient outcomes.


Assuntos
Ciclodextrinas , Doença de Niemann-Pick Tipo C , Recém-Nascido , Humanos , Doença de Niemann-Pick Tipo C/tratamento farmacológico , Ciclodextrinas/uso terapêutico , 2-Hidroxipropil-beta-Ciclodextrina/uso terapêutico , Resultado do Tratamento , Progressão da Doença
2.
Front Neurol ; 13: 918255, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36247789

RESUMO

Objective: This study evaluated the feasibility of a matching-pair test using eye-tracking technology to assess nusinersen effectiveness in patients with advanced spinal muscular atrophy (SMA) type I. Methods: This prospective, observational study enrolled patients with 5q-SMA type I who had lost gross motor function. Three different levels of matching-pair tests were conducted using the eye-gaze system (My Tobii; TobiiDynavox Inc.) at baseline, and after 9 and 24 weeks of nusinersen treatment. The primary endpoint was the change from baseline in matching-pair test scores and response times (i.e., the time to answer matching-pair test) at 24 weeks from baseline. Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND), Pediatric Quality of Life inventory for patients with Neuromuscular Disease (PedsQL-NM) and Numerical Rating Scale (NRS) scores were also assessed as secondary endpoints. Analysis of ocular fixation was performed as an additional analysis. This study was registered at https://www.umin.ac.jp/ctr/ (UMIN000033935). Results: Seven patients (one male, six female) aged 5-21 years (median 11 years) were enrolled; all patients were bedridden and six patients were ventilated. All seven patients were able to conduct level 1 matching-pair tests at each assessment; five patients were also able to conduct levels 2 and 3. Two patients (those with the highest CHOP-INTEND scores) were able to complete all tests correctly within 60 s. There was a non-significant trend toward improvement in CHOP-INTEND, PedsQL-NM, and NRS scores over the 6-month period. There were no significant differences in the number of actions, errors, correct answers, or response times between baseline and Week 9 or 24 at any level. However, the result of an additional analysis suggests that detection of eye movement would be useful to evaluate for advanced SMA. Conclusions: Eye-tracking systems are possibly feasible for the assessment of treatment efficacy in patients with advanced SMA type I.

3.
Brain Dev ; 44(8): 583-587, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35562277

RESUMO

BACKGROUND: Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) with aphasia is a rare disorder, with the associated aphasia reported as either Wernicke's or Broca's. Herein, we report a patient with MELAS complicated by thalamic aphasia. CASE: A 15-year-old right-handed girl presented with headache, nausea, right homonymous hemianopsia, and aphasia. She could repeat words said by others, but had word-finding difficulty, paraphasia, and dysgraphia. Brain MRI revealed abnormal signals from the left occipital lobe to the temporal lobe and left thalamus, but Wernicke's area and Broca's area were not involved. Additionally, she had short stature, lactic acidosis, bilateral sensorineural hearing loss, and a maternal family history of diabetes and mild deafness. Based on clinical findings and the presence of a mitochondrial A3243G mutation, she was diagnosed with MELAS. With treatment, the brain MRI lesions disappeared and her symptoms improved. Her aphasia was classified as amnesic aphasia because she could repeat words, despite having word-finding difficulty, paraphasia, and dysgraphia. Based on MRI findings of a left thalamic lesion, we diagnosed her with thalamic aphasia. CONCLUSION: Thalamic aphasia may be caused by MELAS. Assessment of whether repetition is preserved is important for classifying aphasia.


Assuntos
Acidose Láctica , Agrafia , Afasia , Síndrome MELAS , Acidente Vascular Cerebral , Acidose Láctica/complicações , Adolescente , Afasia/etiologia , Feminino , Humanos , Síndrome MELAS/complicações , Síndrome MELAS/diagnóstico , Encefalomiopatias Mitocondriais , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Tálamo/diagnóstico por imagem
4.
Brain Dev ; 44(1): 36-43, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34362595

RESUMO

OBJECTIVE: To clarify the incidence and risk factors of acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) in pediatric patients with febrile status epilepticus (FSE). METHODS: We retrospectively surveyed patients with FSE (≥20 min and ≥40 min) who were younger than 6 years by mailing a questionnaire to 1123 hospitals in Japan. The survey period was 2 years. We then collected clinical data on patients with prolonged febrile seizures (PFS) ≥40 min and those with AESD, and compared clinical data between the PFS and AESD groups. RESULTS: The response rate for the primary survey was 42.3%, and 28.0% of hospitals which had applicable cases responded in the secondary survey. The incidence of AESD was 4.3% in patients with FSE ≥20 min and 7.1% in those with FSE ≥40 min. In the second survey, a total of 548 patients had FSE ≥40 min (AESD group, n = 93; PFS group, n = 455). Univariate analysis revealed significant between-group differences in pH, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine kinase, NH3, procalcitonin (PCT), uric acid, blood urea nitrogen, creatinine (Cr), and lactate. Multivariate analysis using stratified values showed that high PCT was an only risk factor for AESD. A prediction score of ≥3 was indicative of AESD, as determined using the following indexes: HCO3- < 20 mmol/L (1 point), Cl <100 mEq/L (1 point), Cr ≥0.35 mg/dL (1 point), glucose ≥200 mg/dL (1 point), and PCT ≥1.7 pg/mL (2 points). The scoring system had sensitivity of 84.2% and specificity of 81.0%. CONCLUSION: Incidence data and prediction scores for AESD will be useful for future intervention trials for AESD.


Assuntos
Encefalopatias/diagnóstico , Encefalopatias/epidemiologia , Convulsões Febris/diagnóstico , Convulsões Febris/epidemiologia , Estado Epiléptico/diagnóstico , Estado Epiléptico/epidemiologia , Pré-Escolar , Epilepsia/diagnóstico , Feminino , Hospitais/estatística & dados numéricos , Humanos , Incidência , Lactente , Japão/epidemiologia , Masculino , Estudos Retrospectivos , Fatores de Risco
5.
Brain Dev ; 43(7): 809-813, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33958241

RESUMO

BACKGROUND: Transient periictal MRI abnormalities (TPMA) are caused by seizures, and may completely or partially reverse within a few days following seizure. Although TPMA are usually observed in patients with status epilepticus (SE), they have also been rarely reported after isolated/recurrent seizures not fulfilling the criteria for SE. Herein, we present a case of a 1-year-old girl with TPMA. CASE: A 1-year-old girl with Apert syndrome and epilepsy showed MRI abnormalities in the cortico-subcortical areas of the left temporal, occipital and parietal lobes, as well as the left thalamus. These abnormalities showed as a hyperintense signal on diffusion-weighted imaging and a hypointense signal on apparent-diffusion coefficient maps. On follow-up MRI after 3 days, the abnormal signals were completely reversed. We confirmed TPMA after eliminating other possibilities. When treatment was withdrawn, the patient regained consciousness immediately and did not show any abnormality on subsequent MRI. CONCLUSION: TPMA may occur in young children; recognizing this possibility is important for making the diagnosis and conducting appropriate treatment. As a previous study revealed, the distribution of signal changes in cortico-subcortical areas and the ipsilateral thalamus may be a characteristic feature of TPMA.


Assuntos
Acrocefalossindactilia/cirurgia , Epilepsia/diagnóstico por imagem , Epilepsia/patologia , Eletroencefalografia , Epilepsia/fisiopatologia , Epilepsia/terapia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética
6.
Sci Rep ; 11(1): 1552, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33452387

RESUMO

Moyamoya disease (MMD) is characterized by progressive bilateral stenotic changes in the terminal portion of the internal carotid arteries. Although RNF213 was identified as a susceptibility gene for MMD, the exact pathogenesis remains unknown. Immunohistochemical analysis of autopsy specimens from a patient with MMD revealed marked accumulation of hyaluronan and chondroitin sulfate (CS) in the thickened intima of occlusive lesions of MMD. Hyaluronan synthase 2 was strongly expressed in endothelial progenitor cells in the thickened intima. Furthermore, MMD lesions showed minimal staining for CS and hyaluronan in the endothelium, in contrast to control endothelium showing positive staining for both. Glycosaminoglycans of endothelial cells derived from MMD and control induced pluripotent stem cells demonstrated a decreased amount of CS, especially sulfated CS, in MMD. A computational fluid dynamics model showed highest wall shear stress values in the terminal portion of the internal carotid artery, which is the predisposing region in MMD. Because the peri-endothelial extracellular matrix plays an important role in protection, cell adhesion and migration, an altered peri-endothelial matrix in MMD may contribute to endothelial vulnerability to wall shear stress. Invading endothelial progenitor cells repairing endothelial injury would produce excessive hyaluronan and CS in the intima, and cause vascular stenosis.


Assuntos
Células Endoteliais/metabolismo , Doença de Moyamoya/fisiopatologia , Adenosina Trifosfatases/metabolismo , Adolescente , Idoso , Fenômenos Biomecânicos/fisiologia , Artéria Carótida Interna/patologia , Espessura Intima-Media Carotídea , Sulfatos de Condroitina/análise , Células Endoteliais/fisiologia , Endotélio/metabolismo , Feminino , Predisposição Genética para Doença , Humanos , Ácido Hialurônico/análise , Hidrodinâmica , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Doença de Moyamoya/metabolismo , Resistência ao Cisalhamento/fisiologia , Estresse Mecânico , Ubiquitina-Proteína Ligases/metabolismo
7.
Front Psychiatry ; 12: 801641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095615

RESUMO

The negative and cognitive symptoms of schizophrenia and related disorders may be due to reduced dopaminergic tone in cortical brain areas. Alteration in the function of dopamine (DA) D3 receptors may play a role in this cortical hypofunctionality and underlie the deficits in social behaviors and cognitive functions in schizophrenia. Cariprazine is a potent DA D3-preferring D3/D2 receptor partial agonist that is approved for the treatment of schizophrenia and bipolar disorder. The objective of the study was to compare the abilities of cariprazine, aripiprazole (another DA receptor partial agonist with more D2 receptor preference), and ABT-925 (a selective DA D3 antagonist) to counteract the social deficit and neurochemical alterations induced by the D3 receptor-preferring agonist (+)-PD 128907 (PD) in rats. Administration of PD (0.16 mg/kg; s.c.) induced a marked (-72%) but short-lasting disruption of the defensive social aggregation behavior (huddling) in the first 10-min period. Cariprazine at all doses (0.1, 0.3, 1 mg/kg; p.o.) almost completely abolished the PD-induced disruption of huddling. Likewise, ABT-925 (3 mg/kg; p.o.) and to a lesser extent aripiprazole (20 mg/kg; p.o.) were effective in blocking the PD-induced disruption of huddling. As measured by microdialysis, the highest dose of cariprazine prevented a PD-induced decrease in DA levels (40-80 min post PD dose) in the medial prefrontal cortex (mPFC), whereas aripiprazole did not have a significant effect. ABT-925 significantly counteracted the effect of PD at 80 min post-dose. In the nucleus accumbens (nAcc) shell, the highest dose of cariprazine, as well as ABT-925 and aripiprazole, significantly reversed the PD-induced decrease in DA levels. Taken together, these data provide behavioral and in vivo neurochemical evidence for the preferential DA D3 receptor action of cariprazine in the rat. This property of cariprazine may offer therapeutic benefits against the cognitive deficits and negative/depressive symptoms of schizophrenia and related disorders.

8.
Brain Dev ; 43(3): 482-485, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33248857

RESUMO

Paroxysmal abnormal eye movement in early infancy is one of the initial symptoms of glucose transporter 1 deficiency syndrome (GLUT1DS). We describe four early infants with transient hypoglycorrhachia presenting with abnormal eye movements. Their symptoms disappeared after the introduction of a ketogenic diet (KD), and their development was normal. Since no variants in SLC2A1 were detected, the CSF-to-blood glucose ratios (C/B) were re-examined, and within normal range. None of the four patients displayed recurrent symptoms after withdrawal from the KD. Because long-term KD has potential adverse effects and could affect the quality of life of patients and their families, re-examination of CSF glucose during late infancy should be considered in the case of absence of the SLC2A1 pathogenic variant.


Assuntos
Glucose/líquido cefalorraquidiano , Transtornos da Motilidade Ocular , Dieta Cetogênica , Humanos , Recém-Nascido , Masculino
9.
Front Pediatr ; 8: 438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32850551

RESUMO

Background: Ileocolic intussusception is the most common form of intussusception in children. Intussusception in the appendix or cecum without a lead point in a child is very rare and was found with total colonoscopy (TCS) and computed tomography. Case Presentation: A 9 year-old boy was admitted to our hospital with fever, vomiting, and two episodes of bloody diarrhea. Inflammatory bowel disease was suspected; TCS was performed and revealed intussusception whose advanced region was in the cecum. The diagnosis was idiopathic cecum intussusception. This case was unusual in that intussusception had occurred at a young age but without lead point; in addition, the intussusception had also occurred at the tip of the cecum. The intussusception was safely reduced by endoscopic procedures, and after improvement in the vomiting, the patient was safely discharged and has had no bloody stools since. Conclusion: We demonstrated cecal intussusception without lead point observed on TCS in a child.

10.
Psychopharmacology (Berl) ; 235(5): 1593-1607, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29637288

RESUMO

RATIONALE: Aberrant glutamatergic, dopaminergic, and GABAergic neurotransmission has been implicated in schizophrenia. Cariprazine reverses the behavioral effects observed in the rat phencyclidine (PCP)-induced model of schizophrenia; however, little is known about its in vivo neurochemistry. OBJECTIVES: The study aims to compare the effects of cariprazine and aripiprazole on PCP-induced changes in the extracellular levels of glutamate, dopamine, serotonin, noradrenaline, and GABA in the rat medial prefrontal cortex (mPFC), and on locomotor activation. METHODS: Microdialysis was performed in awake rats with probes placed into the mPFC. Rats (n = 7/group) received vehicle (saline), cariprazine (0.05, 0.2, or 0.8 mg/kg), or aripiprazole (3 or 20 mg/kg) via gavage. After 60 min, 5 mg/kg PCP was administered intraperitoneally (i.p.). Samples were taken before drug administration, during pretreatment, and after PCP injection. Locomotor activity recording and microdialysis sampling occurred simultaneously. RESULTS: PCP treatment increased extracellular levels of all the neurotransmitters tested except GABA, for which there were no significant changes. Cariprazine and aripiprazole dose-dependently inhibited the PCP-induced increases of tested neurotransmitters. Overall effects were significant for higher cariprazine doses and both aripiprazole doses for glutamate and noradrenaline, for higher cariprazine doses and 20 mg/kg aripiprazole for dopamine, and for 0.8 mg/kg cariprazine and 20 mg/kg aripiprazole for serotonin and locomotor activity. CONCLUSION: Both cariprazine and aripiprazole dose-dependently attenuated PCP-induced hyperlocomotion and acute increases in glutamate, dopamine, noradrenaline, and serotonin levels in the mPFC; cariprazine was approximately 5-fold more potent than aripiprazole.


Assuntos
Antipsicóticos/uso terapêutico , Líquido Extracelular/metabolismo , Locomoção/fisiologia , Piperazinas/uso terapêutico , Córtex Pré-Frontal/metabolismo , Esquizofrenia/metabolismo , Animais , Antipsicóticos/farmacologia , Modelos Animais de Doenças , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Líquido Extracelular/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Microdiálise/métodos , Norepinefrina/metabolismo , Fenciclidina/toxicidade , Piperazinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Esquizofrenia/induzido quimicamente , Esquizofrenia/tratamento farmacológico , Serotonina/metabolismo , Ácido gama-Aminobutírico/metabolismo
11.
J Pediatr ; 196: 161-167.e1, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29499989

RESUMO

OBJECTIVE: To clarify the clinical, pathologic, and genetic features of neonatal Dubin-Johnson syndrome. STUDY DESIGN: Ten patients with neonatal Dubin-Johnson syndrome were recruited from 6 pediatric centers in Japan between September 2013 and October 2016. Clinical and laboratory course, macroscopic and microscopic liver findings, and molecular genetic findings concerning ATP-binding cassette subfamily C member 2 (ABCC2) were retrospectively and prospectively examined. RESULTS: All neonates exhibited cholestasis, evident as prolonged jaundice with or without acholic stools and elevations of serum direct bilirubin as well as γ-glutamyltransferase or total bile acids. Only 38% (3 of 8) of patients who underwent liver biopsy showed a grossly black liver or melanin-like pigment deposits in hepatocytes; their biopsies were performed in early infancy. Immunohistochemically, all liver specimens showed no expression of multidrug resistance-associated protein 2 but increased expression of the bile salt export pump protein. Homozygous or compound heterozygous pathogenic variants of ABCC2 were identified in all patients, representing 11 distinct pathogenic variants including 2 not previously reported. CONCLUSIONS: Immunohistochemical staining of the liver for multidrug resistance-associated protein 2 and molecular genetic analysis of ABCC2 are crucial for accurate diagnosis of neonatal Dubin-Johnson syndrome.


Assuntos
Icterícia Idiopática Crônica/diagnóstico , Icterícia Idiopática Crônica/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Ácidos e Sais Biliares/metabolismo , Bilirrubina/metabolismo , China , Feminino , Hepatócitos/metabolismo , Humanos , Recém-Nascido , Doenças do Recém-Nascido , Japão , Icterícia , Icterícia Idiopática Crônica/patologia , Icterícia Idiopática Crônica/cirurgia , Fígado/metabolismo , Fígado/patologia , Masculino , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Mutação , Estudos Prospectivos , Estudos Retrospectivos
12.
Toxicol Lett ; 176(3): 207-14, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18221844

RESUMO

The potential of carbon tetrachloride (CCl4) to induce pre-neoplastic lesions in rat liver using a medium-term liver assay (Ito method) for the prediction of carcinogenicity was examined by nose-only inhalation exposure of male rats (15/group) to CCl4 vapor at concentrations of 0, 1, 5, 25, 125 ppm for 6h/day, 6 day/week, for a period of 6 weeks. The numbers and area of glutathione S-transferase placental (GST-P) positive foci were then determined. Additionally, other histopathological observations on the livers were recorded and serum chemical parameters and CCl4 concentrations in blood were measured. The areas and numbers of GST-P positive foci significantly increased in the CCl4-exposed rats at 25 and 125 ppm; but not at concentrations of 1 and 5 ppm. CCl4 blood concentration 24h after initiation of exposure in the 125 ppm group remained at about 5% of the 6h maximum concentration. These data from CCl4-exposed rats clearly show that inhalation exposure can be used in the rat medium-term liver assay, the method is available for the screening of volatile chemicals and is therefore a useful tool in cancer risk assessment. This is the first report of the use of inhalation exposure in this medium-term predictive assay.


Assuntos
Tetracloreto de Carbono/toxicidade , Carcinógenos/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Fígado/efeitos dos fármacos , Animais , Bioensaio , Peso Corporal/efeitos dos fármacos , Tetracloreto de Carbono/sangue , Testes de Carcinogenicidade/métodos , Carcinógenos/farmacocinética , Relação Dose-Resposta a Droga , Glutationa S-Transferase pi/metabolismo , Imuno-Histoquímica , Exposição por Inalação , Fígado/enzimologia , Fígado/patologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Valor Preditivo dos Testes , Ratos , Ratos Endogâmicos F344
13.
Anal Sci ; 20(3): 557-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15068305

RESUMO

A highly sensitive and selective fluorometric method for the determination of histamine and histidine has been developed. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent followed by reversed-phase liquid chromatography. The analytes, containing two amino moieties in a molecule, were converted to the corresponding dipyrene-labeled derivatives by derivatization. The derivatives afforded intramolecular excimer fluorescence (440 - 540 nm), which can clearly be discriminated from the normal fluorescence (360 - 420 nm) emitted from reagent blanks. The detection limits (signal-to-noise ratio = 3) were femto mole levels.


Assuntos
Histamina/análise , Histidina/análise , Calibragem , Cromatografia Líquida , Corantes Fluorescentes , Indicadores e Reagentes , Espectrometria de Massas , Pirenos/química , Padrões de Referência , Soluções , Espectrometria de Fluorescência
14.
Biomed Chromatogr ; 17(8): 509-16, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14648607

RESUMO

A highly sensitive, selective and simple method is described for the determination of histamine by high-performance liquid chromatography (HPLC) with fluorescence detection. The method is based on an intramolecular excimer-forming fluorescence derivatization of histamine with 4-(1-pyrene)butyric acid N-hydroxysuccinimide ester (PSE), followed by reversed-phase HPLC. Histamine, having two amino moieties in a molecule, was converted to the dipyrene-labeled derivative by reaction with PSE. The derivative afforded intramolecular excimer fluorescence (450-540 nm), which can clearly be discriminated from the monomer fluorescence (370-420 nm) emitted from PSE. Typically, a 10 micro L sample solution was mixed with 100 micro L of derivatization reagent solution, which was a mixture of 0.5 mm PSE in acetonitrile and 0.5 mm potassium carbonate in water (8:2, v/v). The derivatization was carried out at 100 degrees C for 90 min. The PSE derivative of histamine could be separated by reversed-phase ODS column with isocratic elution using acetonitrile:water (82:18, v/v) containing 0.03% triethylamine. The detection limit (singnal-to-noise ratio = 3) of histamine was 0.5 fmol for a 30 micro L injection. The method was successfully applied to the determination of histamine in human urine, and had enough selectivity and sensitivity for urinary histamine quantification.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Histamina/urina , Espectrometria de Fluorescência/métodos , Adulto , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
J Neurosci Methods ; 127(1): 11-7, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12865144

RESUMO

This paper describes a sensitive and selective liquid chromatographic method with fluorescence detection for determination of histamine in brain microdialysis samples from awake rats. Samples containing histamine (10 microl) were derivatized with 20 microl of the reagent consisting of 3 mM 4-(1-pyrene)butyric acid N-hydroxysuccinimide ester (PSE), 3 mM potassium carbonate and acetonitrile (1:1:18, v/v), thereafter 20 microl volume was injected onto the microbore column packed with C18 silica gel. The histamine derivative contained two pyrene moieties, which generated intramolecular excimer fluorescence (450-540 nm) and allowed clear discrimination from the monomer fluorescence (360-420 nm) emitted by PSE itself. The separation of histamine-pyrene derivative was achieved within 25 min, the detection limit (S/N=3) was 0.3 fmol histamine in 20 microl injected. The basal extracellular levels of histamine collected in 10-min fractions (fmol per 10 microl, mean+/-S.D., not corrected for recovery, n=10 rats) were 35.45+/-4.56 (hypothalamus), 9.05+/-1.56 (prefrontal cortex), 7.83+/-0.86 (hippocampus) and 6.54+/-0.66 (striatum). The voltage-sensitive release of histamine was evaluated by perfusing the probes with high (100 mM) concentration of potassium ions or with sodium channel blocker tetrodotoxin (1 microM), and the calcium-dependent release was tested by perfusion with calcium-free Ringer solution. These data, together with physiologically induced increase of extracellular histamine in four examined brain regions during forced swimming demonstrate that this method is suitable for high-sensitive determination of neuronally released histamine under various pharmacological and physiological conditions.


Assuntos
Marcadores de Afinidade/análise , Encéfalo/metabolismo , Histamina/análise , Microdiálise/métodos , Pirenos/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Histamina/química , Masculino , Ratos , Ratos Sprague-Dawley
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