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1.
Eur J Neurol ; 27(12): 2463-2472, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32697875

RESUMO

BACKGROUND AND PURPOSE: Urinary liver-type fatty-acid binding protein (L-FABP), which is a biomarker of kidney tubule injury, has been studied extensively and established as a risk marker of acute kidney injury (AKI). The aim of this study was to investigate whether kidney tubule injury is associated with the development of AKI and mortality in patients with acute ischaemic stroke. METHODS: Acute ischaemic stroke patients hospitalized in the stroke care unit (SCU) within 24 h after symptom onset were prospectively investigated. AKI was defined on the basis of Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Baseline urinary L-FABP was measured on admission. We evaluated the associations among urinary L-FABP, incidence of AKI, and 90-day mortality adjusted for renal function, albuminuria and other potentially predictive variables, using multivariable analysis. RESULTS: In total, 527 acute ischaemic stroke patients (342 men, median age 74 years) were enrolled in the study. Twenty-seven patients (5.1%) experienced AKI within 7 days of admission. In the univariate analysis, high urinary L-FABP level had positive associations with AKI [53.8 µg/g creatinine (Cr) vs. 3.9 µg/g Cr; P < 0.001] and 90-day mortality (15.5 µg/g Cr vs. 4.0 µg/g Cr; P < 0.001). In the multivariate analysis, elevated urinary L-FABP level (per 10-µg/g Cr increase) was independently associated with AKI (odds ratio 1.225, 95% confidence interval (CI) 1.083-1.454; P = 0.003) and 90-day mortality (hazard ratio 1.091, 95% CI 1.045-1.138; P < 0.001). CONCLUSION: Urinary biomarkers of kidney tubule injury are independently associated with the development of AKI and 90-day mortality in patients with acute ischaemic stroke treated at the SCU.


Assuntos
Injúria Renal Aguda , Isquemia Encefálica , AVC Isquêmico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Idoso , Biomarcadores , Isquemia Encefálica/complicações , Feminino , Humanos , Túbulos Renais , Masculino
2.
Eur J Neurol ; 24(11): 1399-1406, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28799181

RESUMO

BACKGROUND AND PURPOSE: Anticoagulant treatment with a vitamin K antagonist (VKA) has been reported to reduce stroke severity when patients with atrial fibrillation (AF) suffer acute ischaemic stroke (AIS). Direct oral anticoagulant (DOAC) therapy also has the potential to reduce the initial severity of AIS. However, the effect of DOAC therapy on the severity of AIS is not well known. The aim of the present study was to investigate the effect of DOACs on initial stroke severity in patients with AIS and non-valvular AF. METHODS: From March 2011 to July 2016, consecutive patients with AIS having non-valvular AF were recruited. The effects of prior DOAC treatment on severity were assessed by multivariate logistic regression analyses. RESULTS: A total of 484 patients [208 women; median age 79 (interquartile range, 71-85) years; National Institutes of Health Stroke Scale (NIHSS) score 9 (interquartile range, 3-20)] were enrolled. Of these, 352 (73%) were on no anticoagulant medication, 54 (11%) were undertreated with a VKA, 35 (7%) were sufficiently treated (admission prothrombin time-international normalized ratio: ≥2.0 for patients <70 years old and ≥1.6 for ≥70 years old) with a VKA and 43 (9%) were on a DOAC. The initial NIHSS score (median 10 in patients with no anticoagulation, 13 in undertreated VKA, 7 in sufficient VKA and 6 in DOAC, P = 0.018) was different among the groups. Multivariate analysis showed that DOAC was independently and negatively associated with severe (initial NIHSS score ≥ 10) stroke (odds ratio, 0.39; P = 0.041), compared with no anticoagulant therapy. CONCLUSIONS: Direct oral anticoagulant treatment prior to the event should reduce initial stroke severity in patients with AIS and non-valvular AF.


Assuntos
Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Isquemia Encefálica/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Feminino , Humanos , Coeficiente Internacional Normatizado , Masculino , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico
4.
Pharmacopsychiatry ; 44(7): 346-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21989600

RESUMO

A case of pharmacoresistant convulsions after selegiline overdose is reported. A 50-year-old male having been suffering from bipolar II disorder for 16 years attempted suicide by taking an overdose of 195 mg selegiline with other psychotropics. He developed recurrent pharmacoresistant seizure from 12th day to 19th day after selegiline overdose. He also had visual hallucinations and temporary high blood pressure. The authors suspect that the catecholamine-influenced convulsions and visual hallucinations that manifested during the period increased by the MAO-inhibiting action of selegiline which lasts about 2 weeks.


Assuntos
Overdose de Drogas/complicações , Alucinações/induzido quimicamente , Inibidores da Monoaminoxidase/intoxicação , Convulsões/induzido quimicamente , Selegilina/intoxicação , Anticonvulsivantes/uso terapêutico , Transtorno Bipolar/complicações , Transtorno Bipolar/tratamento farmacológico , Coma/induzido quimicamente , Diazepam/uso terapêutico , Resistência a Medicamentos , Alucinações/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Fenitoína/uso terapêutico , Convulsões/tratamento farmacológico , Tentativa de Suicídio
5.
Br J Psychiatry ; 193(4): 338-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18827301

RESUMO

Immune dysfunction has been proposed as a mechanism for the pathophysiology of autistic-spectrum disorders. The selectin family of adhesion molecules plays a prominent role in immune/inflammatory responses. We determined the serum levels of three types of soluble-form selectin (sP, sL and sE) in 15 men with high-functioning autism and 22 age-matched healthy controls by enzyme-linked immunosorbent assay. Levels of sP-selectin and sL-selectin were significantly lower in patients than in controls. Furthermore, sP-selectin levels were negatively correlated with impaired social development during early childhood.


Assuntos
Transtorno Autístico/sangue , Selectina-P/sangue , Estudos de Casos e Controles , Selectina E/sangue , Ensaio de Imunoadsorção Enzimática , Humanos , Selectina L/sangue , Masculino , Adulto Jovem
6.
Acta Psychiatr Scand ; 118(6): 503-4, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18764838

RESUMO

OBJECTIVE: Burning mouth syndrome (BMS) is an orofacial pain disorder characterized by a chronic, idiopathic burning sensation of the oral mucosa that mostly affects middle-aged women. Although both psychological and neuropathological factors have been postulated to underlie BMS, the pathogenic mechanism of the condition remains controversial, as do the treatment strategies. METHOD: A single case was reported. RESULTS: Ms A, a 66-year-old woman with BMS type 1, which is characterized by daily burning pain associated with circadian variation, underwent electroconvulsive therapy (ECT). After the completion of 12 ECTs, the pain markedly diminished and the pronounced ECT effect persisted over the subsequent 24-week period of observation. CONCLUSION: To our knowledge, this is the first clinical report on the efficacy of ECT for treating pain associated with BMS. ECT can be considered to be an option for treating individuals with enduring and intractable intraoral burning pain.


Assuntos
Síndrome da Ardência Bucal/terapia , Eletroconvulsoterapia , Idoso , Síndrome da Ardência Bucal/diagnóstico , Síndrome da Ardência Bucal/psicologia , Feminino , Humanos , Medição da Dor
7.
Oper Dent ; 43(4): E166-E172, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29513639

RESUMO

The aim of this study was to use ultrasonography to evaluate the effect of the self-assembling peptide P11-4 on acid erosion prevention. Curodont Repair (CR), which includes peptide P11-4, was used. Rectangular prisms of bovine enamel (4×1×1 mm) were immersed in pure orange juice for a period of 5 minutes six times per day for 28 days. These samples were divided into four groups of six specimens each and treated differently for an additional period of 28 days: 1) baseline group specimens were stored in artificial saliva; 2) CR group specimens were exposed to curodont without acid challenge; 3) NCRA (no curodont+acid challenge) specimens were treated with orange juice without curodont exposure; and 4) CRA (CR+acid challenge) specimens were treated with curodont before treatment with orange juice. The propagation time of longitudinal ultrasonic velocity (UV) was measured. Ultrastructural observation of each tested enamel surface was carried out using field-emission scanning electron microscopy (SEM). The UV data were analyzed using two-way analysis of variance with time and treatment as confounding factors. Post hoc pairwise tests among groups were performed using the Tukey honestly significant difference test. The average UV in intact bovine enamel for the baseline group ranged from 4,483 to 4,549 m/s and did not vary significantly within the test period. The average ultrasonic velocity (UV) in all samples decreased after the initial erosion. The UV in NCRA decreased further over time. Increased UVs were found for CR and CRA. For CR and CRA, there was no significant difference in UV at the end of the experiment from the initial value before erosion. In the results of SEM observation, the CR and CRA groups had similar morphologic features in that etching patterns were not clearly due to precipitation between the enamel rods. From the results of this in vitro study, it might be concluded that applying enamel matrix derivatives and self-assembling peptides on erosive lesions can improve remineralization.


Assuntos
Oligopeptídeos/química , Erosão Dentária/prevenção & controle , Animais , Bovinos , Citrus/química , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Saliva Artificial/química , Erosão Dentária/diagnóstico por imagem , Ultrassonografia/métodos
8.
J Clin Invest ; 100(8): 2015-21, 1997 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9329965

RESUMO

The Long-Evans Tokushima Lean (LETL) rat, characterized by rapid onset of insulin-dependent (type I) diabetes mellitus (IDDM), no sex difference in the incidence of IDDM, autoimmune destruction of pancreatic beta cells, and no significant T cell lymphopenia, is a desirable animal model for human IDDM. We have established a diabetes-prone substrain of the LETL rat, named Komeda Diabetes-Prone (KDP) rat, showing a 100% development of moderate to severe insulitis within 220 d of age. The cumulative frequency of IDDM was 70% at 120 d of age, and reached 82% within 220 d of age. Here, we performed the first genome-wide scan for non-MHC IDDM susceptibility genes in this strain. The analysis of three crosses has led to the revelation of a major IDDM susceptibility gene, termed Iddm/kdp1, on rat chromosome (Chr) 11. Homozygosity for the KDP allele at this locus is shown to be essential for the development of moderate to severe insulitis and the onset of IDDM. Comparative mapping suggests that the homologues of Iddm/ kdp1 are located on human Chr 3 and mouse Chr 16 and would therefore be different from previously reported IDDM susceptibility genes.


Assuntos
Diabetes Mellitus Tipo 1/genética , Ilhotas Pancreáticas/patologia , Pancreatite/genética , Animais , Mapeamento Cromossômico , Cromossomos Humanos Par 3 , Cruzamentos Genéticos , Diabetes Mellitus Tipo 1/etiologia , Suscetibilidade a Doenças , Ligação Genética , Marcadores Genéticos , Genoma , Genótipo , Haplótipos , Homozigoto , Humanos , Camundongos , Ratos , Ratos Endogâmicos , Índice de Gravidade de Doença , Especificidade da Espécie
9.
Oncogene ; 36(9): 1191-1199, 2017 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-27797375

RESUMO

Long non-coding RNAs (lncRNAs) are frequently dysregulated in a variety of human cancers. However, their biological roles in these cancers remain incompletely understood. In this study, we analyze the gene expression profiles of colon cancer tissues and identify a previously unannotated lncRNA, FLJ39051, that we term GSEC (G-quadruplex-forming sequence containing lncRNA), as a lncRNA that is upregulated in colorectal cancer. We further demonstrate that knockdown of GSEC results in the reduction of colon cancer cell motility. We also show that GSEC binds to the DEAH box polypeptide 36 (DHX36) RNA helicase via its G-quadruplex-forming sequence and inhibits DHX36 G-quadruplex unwinding activity. Moreover, knockdown of DHX36 restores the reduced migratory activity of colon cancer cells caused by GSEC knockdown. These results suggest that GSEC plays an important role in colon cancer cell migration by inhibiting the function of DHX36 via its G-quadruplex structure.


Assuntos
Movimento Celular , Neoplasias do Colo/patologia , RNA Helicases DEAD-box/antagonistas & inibidores , Quadruplex G , RNA Longo não Codificante/genética , RNA Neoplásico/metabolismo , Apoptose , Sítios de Ligação , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Humanos , Estadiamento de Neoplasias , Prognóstico , Ligação Proteica , RNA Longo não Codificante/metabolismo , RNA Neoplásico/genética , Células Tumorais Cultivadas
10.
Oper Dent ; 42(6): E177-E187, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28976846

RESUMO

The present study determined the mechanical properties and volumetric polymerization shrinkage of different categories of resin composite. Three high viscosity bulk fill resin composites were tested: Tetric EvoCeram Bulk Fill (TB, Ivoclar Vivadent), Filtek Bulk Fill posterior restorative (FB, 3M ESPE), and Sonic Fill (SF, Kerr Corp). Two low-shrinkage resin composites, Kalore (KL, GC Corp) and Filtek LS Posterior (LS, 3M ESPE), were used. Three conventional resin composites, Herculite Ultra (HU, Kerr Corp), Estelite ∑ Quick (EQ, Tokuyama Dental), and Filtek Supreme Ultra (SU, 3M ESPE), were used as comparison materials. Following ISO Specification 4049, six specimens for each resin composite were used to determine flexural strength, elastic modulus, and resilience. Volumetric polymerization shrinkage was determined using a water-filled dilatometer. Data were evaluated using analysis of variance followed by Tukey's honestly significant difference test (α=0.05). The flexural strength of the resin composites ranged from 115.4 to 148.1 MPa, the elastic modulus ranged from 5.6 to 13.4 GPa, and the resilience ranged from 0.70 to 1.0 MJ/m3. There were significant differences in flexural properties between the materials but no clear outliers. Volumetric changes as a function of time over a duration of 180 seconds depended on the type of resin composite. However, for all the resin composites, apart from LS, volumetric shrinkage began soon after the start of light irradiation, and a rapid decrease in volume during light irradiation followed by a slower decrease was observed. The low shrinkage resin composites KL and LS showed significantly lower volumetric shrinkage than the other tested materials at the measuring point of 180 seconds. In contrast, the three bulk fill resin composites showed higher volumetric change than the other resin composites. The findings from this study provide clinicians with valuable information regarding the mechanical properties and polymerization kinetics of these categories of current resin composite.


Assuntos
Resinas Compostas/química , Metacrilatos/química , Elasticidade , Humanos , Polimerização , Resistência à Tração
11.
Endocrinology ; 141(10): 3774-82, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11014233

RESUMO

Using mouse osteoclast-like cells (OCs), we have shown that short exposure to calcitonin (CT) resulted in prolonged reduction of CT binding by inhibiting de novo CT receptor (CTR) synthesis. Additionally, CT-treated OCs demonstrated resistance to CT rechallenge on the inhibitory effect of CT in osteoclastic bone resorption. There is, however, scant information on CT effects on human osteoclasts. In this study, we examined the features of CTR down-regulation and its recovery after short exposure to CT of human OCs. OCs were prepared by treatment of peripheral blood mononuclear cells in vitro with osteoclast differentiation factor and macrophage colony-stimulating factor. Treatment of OCs with salmon CT (sCT) and human CT (hCT) resulted in a dose-dependent reduction in [125I]sCT binding capacity. Continued receptor occupancy by ligand was excluded by using a glycine-acid washing procedure. Treatment with sCT reduced CTR messenger RNA expression, suggesting that CTR down-regulation is, at least partly, attributable to an inhibition of de novo CTR synthesis. To investigate the intracellular signal transduction pathways that mediate these effects, we examined the effects of activation of the protein kinase (PK)A, PKC, and Ca2+-calmodulin-dependent kinases. Treatment with PKC activators mimicked CT, whereas neither activation of PKA nor elevation of intracellular Ca2+ did so. We further investigated the intracellular signaling pathways responsible for the inhibitory effects of CT on bone resorption, which showed that treatment with PKC activators reproduced the effects of CT. These data suggest that the PKC pathway plays an important role in homologous CTR down-regulation, as well as inhibition of bone-resorbing activity by CT, in human OCs. Short exposure of OCs to CT (10(-9) M, 1 h) reduced [125I]sCT-specific binding for a prolonged period, as we have shown previously in mouse OCs. The reduced specific binding, CTR messenger RNA levels, and CT-sensitive adenylate cyclase responsiveness returned to the control levels by 96 h after removal of CT. These results strongly support the notion that escape from CT inhibition of osteoclastic bone resorption in humans is attributable to the development of resistance by OCs to CT. This study also showed that even short exposure to CT induced prolonged desensitization to CT rechallenge, although the OCs eventually regained responsiveness to sCT rechallenge.


Assuntos
Calcitonina/farmacologia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Osteoclastos/metabolismo , Receptores da Calcitonina/efeitos dos fármacos , Receptores da Calcitonina/metabolismo , Animais , Reabsorção Óssea/fisiopatologia , Células Cultivadas , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ativação Enzimática/fisiologia , Ativadores de Enzimas/farmacologia , Humanos , Ligantes , NF-kappa B/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Inibidores de Proteases/farmacologia , Proteína Quinase C/metabolismo , RNA Mensageiro/metabolismo , Receptores da Calcitonina/genética , Salmão
12.
Endocrinology ; 142(4): 1471-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11250927

RESUMO

Using mouse osteoclast-like cells (OCs), we have shown that treatment with glucocorticoids (GCs) resulted in an increase in calcitonin (CT) binding by enhancing CT receptor (CTR) gene transcription. Additionally, treatment with GCs demonstrated increased sensitivity to CT. There is, however, scant information on the effects of GC or CTR regulation by GCs in human osteoclasts. In this study we examined CTR regulation by GCs and the effects of GCs and CT together in human OCs. OCs were prepared by treatment of peripheral blood mononuclear cells in vitro with soluble receptor activator of nuclear factor-kappaB ligand and macrophage colony-stimulating factor. Treatment of mature OCs with dexamethasone (Dex) resulted in a dose- and time-dependent increase in [(125)I]salmon CT (sCT) binding capacity. Treatment with Dex enhanced CTR messenger RNA (mRNA) expression, suggesting that CTR up-regulation is at least partly due to an increase in de novo CTR synthesis. Triamcinolone and prednisolone reproduced the Dex effect on [(125)I]sCT-specific binding and CTR mRNA expression, but 17beta-estradiol, progesterone, dehydroepiandrosterone, and aldosterone did not. A Scatchard plot analysis showed that Dex enhanced CTR number with a minimal change in the affinity to sCT. Autoradiographic studies using [(125)I]sCT showed that Dex enhanced the CTR density on individual multinuclear OCs. Up-regulation of [(125)I]sCT-specific binding and CTR mRNA expression was seen even in the presence of sCT, but the enhancement diminished subsequently at later times (36-48 h after sCT removal), which was consistent with our previous observation in mouse OCs. This suggests that GCs and CTs act on CTR expression differently, consistent with our previous work using mouse OCs, in which we found that GCs increased transcription of CTR gene expression, whereas CT reduced CTR mRNA stability. The results obtained in this study show that GC increased CTR expression and sensitivity to CT in cells of the human osteoclast lineage and provide the basis for understanding the beneficial effects of combination treatment with GCs and CTs in malignancy-associated hypercalcemia.


Assuntos
Proteínas de Transporte/farmacologia , Glucocorticoides/farmacologia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Glicoproteínas de Membrana/farmacologia , Osteoclastos/metabolismo , Receptores da Calcitonina/biossíntese , Fosfatase Ácida/metabolismo , Autorradiografia , Linhagem Celular , AMP Cíclico/biossíntese , Humanos , Hipercalcemia/metabolismo , Isoenzimas/metabolismo , Osteoclastos/efeitos dos fármacos , Ligante RANK , RNA Mensageiro/biossíntese , Receptor Ativador de Fator Nuclear kappa-B , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fosfatase Ácida Resistente a Tartarato
13.
Hypertension ; 11(5): 483-90, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-2966770

RESUMO

The relationship between kidney function and plasma immunoreactive atrial natriuretic factor (irANF) levels as well as the effects of synthetic human ANF-(99-126) were investigated in 13 patients with mild to moderate chronic renal failure. Under basal conditions, glomerular filtration rate averaged 39 +/- 5 (SEM) ml/min/1.73 m2 and blood pressure (BP) averaged 166/107 +/- 7/2 mm Hg; 12 patients were hypertensive. Plasma irANF levels were significantly increased (98 +/- 16 vs 42 +/- 4 pg/ml in healthy control subjects; p less than 0.001) and correlated (p less than 0.05-0.005) inversely with hematocrit (r = -0.65) and positively with systolic BP (r = 0.75) or fractional sodium excretion (r = 0.75). Human ANF-(99-126) infusion for 45 minutes at 0.034 microgram/kg/min augmented (p less than 0.05-0.01) diuresis and urinary sodium, chloride, calcium, phosphate, and magnesium excretion. During the subsequent 45 minutes of human ANF-(99-126) infusion at a rate of 0.077 microgram/kg/min, diuresis and electrolyte excretion remained elevated (p less than 0.05-0.01). Glomerular filtration rate and effective renal plasma flow were not significantly modified, but filtration fraction rose progressively (p less than 0.01). Human ANF-(99-126) infusion decreased BP (p less than 0.05-0.01), produced hemoconcentration (hematocrit + 7%; p less than 0.01) without negative body fluid balance, and increased (p less than 0.01-0.001) plasma norepinephrine, insulin, and serum free fatty acids; plasma aldosterone and renin activity were unaltered during but rose after cessation of human ANF-(99-126) infusion.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fator Natriurético Atrial/sangue , Falência Renal Crônica/sangue , Rim/fisiologia , Adulto , Idoso , Aldosterona/sangue , Fator Natriurético Atrial/imunologia , Fator Natriurético Atrial/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Hematócrito , Homeostase , Humanos , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Fragmentos de Peptídeos/farmacologia , Renina/sangue , Sódio/urina
14.
J Cereb Blood Flow Metab ; 5(1): 58-64, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3972924

RESUMO

The relationship between local cerebral glucose utilization (LCGU) and local CBF (LCBF) was examined during the action of gamma-hydroxybutyrate (GHB) (900 mg/kg i.v.) in conscious rats. GHB induced discrepant effects on blood flow and metabolism. LCGU was markedly depressed in all structures examined, whereas LCBF was differently affected in that no related changes were observed. Global glucose utilization was markedly depressed (-51%), whereas global blood flow was not significantly altered. The marked dissociation between the changes in global glucose utilization and global blood flow induced by GHB is reflected only to a minor degree in the local values inasmuch as the correlation between LCGU and LCBF was only slightly weakened and its heterogeneity was increased.


Assuntos
Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Glucose/metabolismo , Hidroxibutiratos/farmacologia , Oxibato de Sódio/farmacologia , Animais , Encéfalo/metabolismo , Masculino , Ratos , Ratos Endogâmicos
15.
J Cereb Blood Flow Metab ; 10(6): 765-73, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2211874

RESUMO

The lumped constant of the deoxyglucose method was determined by the steady-state, model-independent method in the brain of normal conscious rats with arterial plasma glucose concentrations varying from normoglycemia (i.e., 8 mM) to hyperglycemia (i.e., 31 mM). The lumped constant for brain was found to decrease very gradually with increasing arterial plasma glucose concentration from a value of approximately 0.45 in the midnormoglycemic range (i.e., 7-8 mM) to approximately 0.38 at 28-31 mM. 3-O-[14C]Methylglucose was used to assess the distribution of glucose within the brain structures in hyperglycemia; the results indicated that the glucose concentration, and therefore also the values for the lumped constant, remain relatively uniform in hyperglycemia with arterial plasma glucose concentrations as high as 34 mM. The values for the lumped constant for rat brain determined in the present studies were combined with those previously determined in this laboratory for hypoglycemia and normoglycemia by the same method to provide a single source for the values for the lumped constant to be used over the full range of arterial plasma glucose concentrations. In several rats the lumped constant for cephalic extracerebral tissues was also evaluated in parallel with those for the brain. The lumped constant for the cephalic extracerebral tissues was found to be about twice that for brain and to be unaffected by changes in arterial plasma glucose levels.


Assuntos
Glicemia/análise , Encéfalo/metabolismo , Desoxiglucose , Glucose/farmacocinética , Algoritmos , Animais , Hiperglicemia/metabolismo , Masculino , Ratos , Ratos Endogâmicos
16.
J Cereb Blood Flow Metab ; 10(4): 499-509, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2347881

RESUMO

The applicability of the [14C]deoxyglucose method for measuring local cerebral glucose utilization (lCMRglc) has been extended for use in hypoglycemia by determination of the values of the lumped constant to be used in rats with plasma glucose concentrations ranging from approximately 2 to 6 mM. Lumped constant values were higher in hypoglycemia and declined from a value of 1.2 at the lowest arterial plasma glucose level (1.9 mM) to about 0.48 in normoglycemia. The distribution of glucose, and therefore also of the lumped constant, was found to remain relatively uniform throughout the brain at the lowest plasma glucose levels studied. lCMRglc in moderate, insulin-induced hypoglycemia (mean arterial plasma glucose concentration +/- SD of 2.4 +/- 0.3 mM) was determined with the appropriate lumped constant corresponding to the animal's plasma glucose concentration and compared with the results obtained in six normoglycemic rats. The weighted average rate of glucose utilization for the brain as a whole was significantly depressed by 14% in the hypoglycemic animals, i.e., 61 mumols/100 g/min in hypoglycemia compared to 71 mumols/100 g/min in the normoglycemic controls (p less than 0.05). lCMRglc was lower in 47 of 49 structures examined but statistically significantly below the rate in normoglycemic rats in only six structures (p less than 0.05) by multiple comparison statistics. Regions within the brainstem were most prominently affected. The greatest reductions, statistically significant or not, occurred in structures in which glucose utilization is normally high, suggesting that glucose delivery and transport to the tissue became rate-limiting first in those structures with the greatest metabolic demands for glucose.


Assuntos
Encéfalo/metabolismo , Desoxiaçúcares , Desoxiglucose , Glucose/metabolismo , Hipoglicemia/metabolismo , Algoritmos , Animais , Masculino , Ratos , Ratos Endogâmicos
17.
FEMS Microbiol Lett ; 172(1): 15-21, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10079523

RESUMO

16S to 23S ribosomal DNA internal transcribed spacer sequences of 47 strains of the genus Microcystis were determined. Derived maximum likelihood and DNA distance trees indicated that Microcystis can be divided into three clusters. The first cluster included toxic and non-toxic strains, the second only toxic ones, and the third only non-toxic ones. The tree topologies were not necessarily correlated with morphospecies distinction or phycobilin pigment composition, and one genotype may have more than one morphotype. Phylogenetic analysis based on intergenic spacer sequences was thought to be effective for understanding relationships among closely related species and strains.


Assuntos
DNA Ribossômico/genética , Microcystis/classificação , Microcystis/genética , Peptídeos Cíclicos/biossíntese , Filogenia , Sequência de Bases , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , Microcistinas , Microcystis/metabolismo , Dados de Sequência Molecular , Ficoeritrina/biossíntese , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Alinhamento de Sequência , Análise de Sequência de DNA
18.
Brain Res ; 324(2): 295-303, 1984 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-6543325

RESUMO

Daily administration of lidocaine results in progressive increases in frequency and duration of convulsions in response to a dose of drug which was previously subconvulsive--a pharmacological kindling phenomenon. The effects of such lidocaine-kindling on local cerebral glucose utilization were determined by the 2-[14C]deoxyglucose method. Lidocaine-treated animals, in the absence of convulsions, exhibited decreased glucose utilization in most brain structures compared to saline-treated animals and showed no increase in aggressive behavior. In animals displaying lidocaine-kindled convulsions there were marked increases in glucose utilization in either the hippocampus and amygdala or in perirhinal cortical areas during the seizure administration; these animals also displayed long-lasting increases in irritable behavior. Seizure duration was positively correlated with the rate of glucose utilization in the hippocampus, amygdala and septum, but inversely correlated in several non-limbic areas. These data suggest that lidocaine-kindled seizures are highly localized to limbic and perirhinal structures and are associated with important behavioral consequences.


Assuntos
Lidocaína/farmacologia , Sistema Límbico/metabolismo , Convulsões/induzido quimicamente , Agressão/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Eletrochoque , Glucose/metabolismo , Humanos , Masculino , Pentilenotetrazol/farmacologia , Ratos , Ratos Endogâmicos , Convulsões/metabolismo , Convulsões/psicologia
19.
Brain Res ; 268(2): 372-6, 1983 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-6871691

RESUMO

By comparing rates of glucose utilization in brains of monkeys in non-REM sleep and two types of awake controls, we attempted to reveal cerebral hypnogenic centers that drive organisms to sleep through increases in their neural activity. Instead we found that metabolic activity is reduced in all the putative hypnogenic centers during sleep as compared to wakefulness. The results thus offer no support for the notion of an active center that either maintains or triggers sleep.


Assuntos
Encéfalo/metabolismo , Glucose/metabolismo , Sono/fisiologia , Animais , Macaca mulatta , Especificidade de Órgãos , Vigília/fisiologia
20.
Neurosci Lett ; 163(1): 67-70, 1993 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-8295735

RESUMO

The effects of intravenous administration of physostigmine at doses of 0.03, 0.095, or 0.3 mg/kg on local cerebral glucose utilization (LCGU) were determined in 3 structures of the visual system of the rat brain by means of the quantitative 2-[14C]deoxyglucose method. LCGU was increased in the superior colliculus (superficial gray layer), but unchanged in the visual cortex and the lateral geniculate body. To determine whether the observed effect of physostigmine on the superior colliculus depended on input from the retina, the highest dose of physostigmine was administered to rats which had previously been enucleated bilaterally. Enucleation decreased LCGU in the superior colliculus of the animals not treated with physostigmine and blocked the effect of physostigmine on LCGU. The effect of physostigmine in the superior colliculus appears, therefore, to depend on input from the retina.


Assuntos
Química Encefálica/efeitos dos fármacos , Glucose/metabolismo , Fisostigmina/farmacologia , Visão Ocular/fisiologia , Animais , Gasometria , Glicemia/metabolismo , Desoxiglucose , Relação Dose-Resposta a Droga , Enucleação Ocular , Corpos Geniculados/efeitos dos fármacos , Corpos Geniculados/metabolismo , Hematócrito , Hemodinâmica/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Retina/fisiologia , Colículos Superiores/efeitos dos fármacos , Colículos Superiores/metabolismo , Córtex Visual/efeitos dos fármacos , Córtex Visual/metabolismo
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