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1.
Clin Psychopharmacol Neurosci ; 19(2): 355-360, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-33888664

RESUMO

OBJECTIVE: Although evidence implicates striatal cholinergic impairment as a mechanism underlying tardive dyskinesia, trials of nonspecific cholinergic agents have been inconclusive. As a partial agonist at specific nicotinic receptor subtypes, varenicline reduces drug-induced dyskinesias in animal models suggesting promise as a treatment for tardive dyskinesia. METHODS: Three schizophrenia patients with tardive dyskinesia who were smokers underwent an open trial of varenicline. After a 2-week baseline, subjects received varenicline 1 mg twice daily. Changes from baseline on the Abnormal Involuntary Movement Scale were measured after a 4-week varenicline stabilization period, and 6 weeks after the smoking quit date in one patient. RESULTS: Varenicline had no effect on mean Abnormal Involuntary Movement Scale scores after 4 weeks. Although smoking decreased after 4 weeks on varenicline and diminished further in one patient after 10 weeks, this also appeared to have no effect on ratings of tardive dyskinesia. CONCLUSION: In contrast to animal models, no significant change in tardive dyskinesia occurred in response to varenicline replacement in three schizophrenia patients. Further investigations of cholinergic mechanisms in tardive dyskinesia are worthwhile as agents for specific cholinergic targets become available for treatment. In addition, treatment trials of tardive dyskinesia should control for smoking status, while patients on antipsychotics receiving nicotine replacement therapies for smoking should be studied further for changes in movement.

4.
J Nerv Ment Dis ; 205(1): 54-57, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27977500

RESUMO

New community-based initiatives being developed to address violent extremism in the United States are utilizing mental health services and leadership. This article reviews current approaches to preventing violent extremism, the contribution that mental illness and psychosocial problems can make to violent extremism, and the rationale for integrating mental health strategies into preventing violent extremism. The authors describe a community-based targeted violence prevention model and the potential roles of mental health professionals. This model consists of a multidisciplinary team that assesses at-risk individuals with comprehensive threat and behavioral evaluations, arranges for ongoing support and treatment, conducts follow-up evaluations, and offers outreach, education, and resources for communities. This model would enable mental health professionals in local communities to play key roles in preventing violent extremism through their practice and leadership.


Assuntos
Programas Governamentais/organização & administração , Serviços de Saúde Mental/organização & administração , Política , Características de Residência , Violência/prevenção & controle , Humanos , Terrorismo/prevenção & controle , Estados Unidos
5.
J Natl Med Assoc ; 103(7): 560-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21999030

RESUMO

Posttraumatic stress disorder (PTSD) has previously been associated with increased risk for a variety of chronic medical conditions and it is often underdiagnosed in minority civilian populations. The current study examined the effects of resilience on the likelihood of having a diagnosis of PTSD in an inner-city sample of primary care patients (n=767). We measured resilience with the Connor-Davidson Resilience Scale, trauma with the Childhood Trauma Questionnaire and Trauma Events Inventory, and assessed for PTSD with the modified PTSD symptom scale. Multiple logistic regression model with presence/absence of PTSD as the outcome yielded 3 significant factors: childhood abuse, nonchild abuse trauma, and resilience. One type of childhood abuse in moderate to severe range (OR, 2.01; p = .0001), 2 or more types of childhood abuse in moderate to severe range (OR, 4.00; p < or = .0001), and 2 or more types of nonchildhood abuse trauma exposure (OR, 3.33; p < or = .0001), were significantly associated with an increased likelihood of PTSD, while resilience was robustly and significantly associated with a decreased likelihood of PTSD (OR, 0.93; p < or = .0001). By understanding the role of resilience in recovery from adverse experiences, improved treatment and interventional methods may be developed. Furthermore, these results suggest a role for assessing resilience in highly traumatized primary care populations as a way to better characterize risk for PTSD and direct screening/psychiatric referral efforts.


Assuntos
Resiliência Psicológica , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Adaptação Psicológica , Adolescente , Adulto , Idoso , Criança , Maus-Tratos Infantis/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Transtornos de Estresse Pós-Traumáticos/diagnóstico , População Urbana , Adulto Jovem
6.
J Affect Disord ; 126(3): 411-4, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20488545

RESUMO

BACKGROUND: Influences of resilience on the presence and severity of depression following trauma exposure are largely unknown. Hence, we examined effects of resilience on depressive symptom severity in individuals with past childhood abuse and/or other trauma exposure. METHODS: In this cross-sectional study of 792 adults, resilience was measured with the Connor-Davidson Resilience Scale, depression with the Beck Depression Inventory (BDI), childhood abuse with the Childhood Trauma Questionnaire, and other traumas with the Trauma Events Inventory. RESULTS: Multiple linear regression modeling with depression severity (BDI score) as the outcome yielded 4 factors: childhood abuse (ß=2.5, p<0.0001), other trauma (ß=3.5, p<0.0001), resilience (ß=-0.5, p<0.0001), and other trauma × resilience interaction term (ß=-0.1, p=0.0021), all of which were significantly associated with depression severity, even after adjusting for age, sex, race, education, employment, income, marital status, and family psychiatric history. Childhood abuse and trauma exposure contributed to depressive symptom severity while resilience mitigated it. CONCLUSIONS: Resilience moderates depressive symptom severity in individuals exposed to childhood abuse or other traumas both as a main effect and an interaction with trauma exposure. Resilience may be amenable to external manipulation and could present a potential focus for treatments and interventions.


Assuntos
População Negra/psicologia , Maus-Tratos Infantis/psicologia , Transtorno Depressivo Maior/psicologia , Transtorno Depressivo/psicologia , Acontecimentos que Mudam a Vida , Resiliência Psicológica , População Branca/psicologia , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/etnologia , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/etnologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade/estatística & dados numéricos , Gravidez , Fatores Socioeconômicos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto Jovem
7.
Neuropsychopharmacology ; 34(2): 509-21, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18580872

RESUMO

The endocannabinoid system and the cannabinoid type 1 receptor (CB1R) are required for the extinction of conditioned fear. CB1 antagonists have been shown to prevent extinction when delivered both systemically and within the amygdala. Anatomical studies suggest that CB1Rs in the basolateral amygdala (BLA) are expressed on GABAergic interneurons expressing the anxiogenic peptide cholecystokinin (CCK). Pre-synaptic CB1Rs inhibit neurotransmitter release, suggesting that CB1R activation during extinction may decrease CCK peptide release as well as GABA release. Thus, we examined whether extinction involves the CB1R modulation of CCK2 receptor activation. We found that intracerebroventricular administration of the CCK2 agonist pentagastrin dose-dependently impaired extinction of conditioned fear. Systemic administration of a CB1 antagonist, rimonabant (SR141716), also potently inhibited extinction learning. This effect was ameliorated with systemic administration of a CCK2 antagonist, CR2945. Furthermore, the extinction blockade by systemic SR141716 was reversed with intra-BLA, but not intrastriatal, infusion of CR2945. Lastly, as extinction usually leads to an increase in Akt phosphorylation, a biochemical effect antagonized by systemic CB1 antagonist treatment, we examined whether CR2945 co-administration would increase extinction-induced p-Akt levels. We observed that extinction-trained animals showed increased Akt phosphorylation following extinction, CB1 antagonist-treated animals showed p-Akt levels similar to those of non-extinction trained animals, and co-administration of CR2945 with SR141716 led to levels of p-Akt similar to those of vehicle-treated, extinction-trained controls. Together, these data suggest that interactions between the endocannabinoid and CCKergic transmitter systems may underlie the process of extinction of conditioned fear.


Assuntos
Moduladores de Receptores de Canabinoides/metabolismo , Colecistocinina/metabolismo , Endocanabinoides , Extinção Psicológica/fisiologia , Receptor CB1 de Canabinoide/metabolismo , Receptor de Colecistocinina B/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Benzodiazepinas/administração & dosagem , Benzodiazepinas/farmacologia , Condicionamento Psicológico/fisiologia , Corpo Estriado/metabolismo , Extinção Psicológica/efeitos dos fármacos , Medo/psicologia , Aprendizagem/fisiologia , Masculino , Pentagastrina/farmacologia , Piperidinas/farmacologia , Pirazóis/farmacologia , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor de Colecistocinina B/agonistas , Receptor de Colecistocinina B/antagonistas & inibidores , Reflexo de Sobressalto/efeitos dos fármacos , Reflexo de Sobressalto/fisiologia , Rimonabanto
8.
J Neurosci ; 28(48): 12682-90, 2008 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-19036961

RESUMO

Neuropeptides are a promising target for novel treatments for anxiety and other psychiatric disorders and neuropeptide Y (NPY) has emerged as a key component of anxiolytic circuits in the brain. For this reason, we have evaluated the role of NPY in the expression and extinction of conditioned fear. We found that intracerebroventricular administration of NPY inhibits both baseline acoustic startle and the expression of fear-potentiated startle. Infusion of NPY (10 pmol/side) into the basolateral, but not the medial, nucleus of the amygdala reproduced the intracerebroventricular effect. Central administration of NPY (10 microg) also enhanced within-session extinction of fear-potentiated startle. This finding, coupled with the growing body of literature correlating NPY with resilience in humans, led us to the hypothesis that NPY may enhance the extinction of conditioned fear. When NPY (10 microg) is administered intracerebroventricularly before extinction training, extinction retention for both the contextual and cued components of conditioned fear is enhanced when tested 48 h later off drug. Additionally, we found that intra-basolateral amygdala administration of the NPY Y(1) receptor antagonist BIBO 3304 (200 pmol/side) before extinction training led to a profound deficit in extinction retention. This is the first evidence that NPY facilitates and an NPY antagonist blocks the extinction of conditioned fear. We believe that the role of NPY in the extinction of conditioned fear may, at least in part, explain the mechanism underlying the association between NPY and psychobiological resilience in humans.


Assuntos
Transtornos de Ansiedade/metabolismo , Encéfalo/metabolismo , Extinção Psicológica/fisiologia , Medo/fisiologia , Neuropeptídeo Y/metabolismo , Reflexo de Sobressalto/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Transtornos de Ansiedade/fisiopatologia , Arginina/análogos & derivados , Arginina/farmacologia , Encéfalo/anatomia & histologia , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Sinais (Psicologia) , Extinção Psicológica/efeitos dos fármacos , Medo/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Neuropeptídeo Y/farmacologia , Testes Neuropsicológicos , Ratos , Ratos Sprague-Dawley , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Receptores de Neuropeptídeo Y/metabolismo , Reflexo de Sobressalto/efeitos dos fármacos
9.
J Hum Genet ; 52(7): 599-606, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17534573

RESUMO

Mutations in 12 different PEX genes can cause a generalized peroxisomal biogenesis disorder with clinical phenotypes ranging from Zellweger syndrome to infantile Refsum disease. To identify the specific PEX gene to be sequenced, complementation analysis is first performed in fibroblasts using catalase immunofluorescence. A patient with a relatively mild phenotype of infantile cholestasis, hypotonia and motor delay had elevated plasma very long-chain fatty acids and bile acid precursors, but fibroblast studies revealed normal or only mildly abnormal peroxisomal parameters and mosaic catalase immunofluorescence. This mosaicism persisted even when the incubation temperature was increased from 37 degrees C to 40 degrees C, a maneuver previously shown to abolish mosaicism by exacerbating peroxisomal dysfunction. As mosaicism precludes complementation analysis, a candidate gene approach was employed. After PEX1 sequencing was unrewarding, PEX12 sequencing revealed homozygosity for a novel c.102A>T (p.R34S) missense mutation affecting a partially conserved residue in the N-terminal region important for localization to peroxisomes. Transfection of patient fibroblasts with wild-type PEX12 cDNA confirmed that a PEX12 defect was the basis for the PBD. Homozygosity for c.102A>T was identified in a second patient of similar ethnic origin also presenting with a mild phenotype. PEX12 is a highly probable candidate gene for direct sequencing in the context of a mild clinical phenotype with mosaicism and minimally abnormal peroxisomal parameters in fibroblasts.


Assuntos
Catalase/metabolismo , Fibroblastos/química , Fibroblastos/metabolismo , Proteínas de Membrana/genética , Mosaicismo , Peroxissomos/genética , Peroxissomos/metabolismo , Doença de Refsum Infantil/genética , Catalase/química , Catalase/genética , Células Cultivadas , Pré-Escolar , Colestase/genética , Colestase/patologia , Fibroblastos/patologia , Imunofluorescência , Temperatura Alta , Humanos , Lactente , Recém-Nascido , Masculino , Peroxissomos/patologia , Fenótipo , Doença de Refsum Infantil/enzimologia , Doença de Refsum Infantil/metabolismo
10.
Eur J Paediatr Neurol ; 11(2): 81-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17188916

RESUMO

Glutaric aciduria type 1 (GA1) is a rare cerebral organic aciduria which typically manifests as an acute encephalopathic crisis followed by profound long-term neurological handicap. We report the diagnosis of 12 new patients from a single laboratory in Israel during a 5-year period. Eleven of the 12 were of Palestinian origin, and only two were related. One patient was asymptomatic whilst one was mildly, one moderately and nine severely affected, two of whom had unusual MRI findings. Two patients had normal glutaric acid excretion and normal blood glutarylcarnitine levels yet glutarylcarnitine excretion was increased, indicating its utility as a diagnostic marker. Four novel GCDH mutations (Thr193_Arg194insHis, Asn329Ser, Thr341Pro, Met405Val) and five previously reported mutations (Ser119Leu, Leu283Pro, Ala293Thr, Gly390Arg and Thr416Ile) were identified. Severely and mildly affected or even asymptomatic patients shared the same genotypes (Thr416Ile/Thre416Ile and Aal293Thr/Thr193_Arg194insHis). Knowledge of the responsible mutation enabled successful prenatal diagnosis on chorionic villous DNA in three families. In conclusion, GA1 is genetically heterogeneous and has a relatively high incidence in the Palestinian population, reflecting the historical tradition of marriages within extended kindreds, particularly in isolated villages. Additional genetic and/or environmental factors must account for the phenotypic heterogeneity in patients with the same genotype. The diagnosis was not suspected in the majority of cases despite typical clinical and/or neuroimaging features, suggesting that glutaric aciduria may be under-diagnosed. Greater awareness of glutaric aciduria amongst pediatricians, neonatologists and radiologists is the key to identifying the disorder in the presymptomatic phase and preventing its catastrophic consequences.


Assuntos
Encefalopatias Metabólicas Congênitas/genética , Glutaratos/urina , Glutaril-CoA Desidrogenase/genética , Glutaril-CoA Desidrogenase/metabolismo , Mutação , Adolescente , Adulto , Encefalopatias Metabólicas Congênitas/metabolismo , Encefalopatias Metabólicas Congênitas/urina , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Isoleucina/genética , Israel/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Treonina/genética
11.
Mol Genet Metab ; 89(4): 332-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16919490

RESUMO

Carnitine-acylcarnitine translocase (CACT) deficiency is a rare disorder of fatty acid oxidation associated with high mortality. Two female newborns of different ethnic origin (the first Anglo-Celtic and the second Palestinian Arab) both died after sudden collapse on day 2 of life. Both had elevated bloodspot long-chain acylcarnitines consistent with either CACT or carnitine palmitoyltransferase II (CPT2) deficiency; the latter was excluded by demonstrating normal CPT2 activity in fibroblasts. Direct sequencing of all SLC25A20 (CACT) gene exons and exon-intron boundaries revealed that Patient 1 was compound heterozygous for a novel c.609-3c>g (IVS6-3c>g) mutation on the paternal allele and a previously described c.326delG mutation on the maternal allele. Patient 2 was homozygous for the same, novel c.609-3c>g mutation. Previously reported SLC25A20 mutations have been almost exclusively confined to a single family or ethnic group. Analysis of fibroblast cDNA by RT-PCR, agarose gel electrophoresis and sequencing of extracted bands showed that both mutations produce aberrant splicing. c.609-3C>G results in exon 7 skipping leading to a frameshift with premature termination seven amino acids downstream. c.326delG was confirmed to produce skipping of exons 3 or 3 plus 4. CACT activity in both patients' fibroblasts was near-zero. For both families, prenatal diagnosis of an unaffected fetus was performed by mutation analysis on CVS tissue in a subsequent pregnancy. Due to the urgency of prenatal diagnosis in the second family, molecular diagnosis was performed prior to demonstration of CACT enzyme deficiency, illustrating that mutation analysis is a rapid and reliable approach to first-line diagnosis of CACT deficiency.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Genes Letais , Proteínas de Membrana Transportadoras/deficiência , Proteínas de Membrana Transportadoras/genética , Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Erros Inatos do Metabolismo dos Aminoácidos/etnologia , DNA Complementar/genética , Evolução Fatal , Feminino , Humanos , Recém-Nascido , Proteínas de Membrana Transportadoras/análise , Mutação , Splicing de RNA/genética , Análise de Sequência de DNA
12.
Ann Neurol ; 59(2): 411-5, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16404748

RESUMO

OBJECTIVE: To determine whether the devastating outcome of neonatal-onset glycine encephalopathy (NKH) could be improved by instituting treatment immediately at birth rather than after symptoms are already well established. METHODS: A newborn with NKH diagnosed prenatally following the neonatal death of a previous affected sibling was treated from birth with oral sodium benzoate (250 mg/kg/day) and the NMDA receptor antagonist ketamine (15 mg/kg/day) immediately after sampling cord blood and cerebrospinal fluid (CSF) for glycine determination. Glycine cleavage system (CGS) activity was determined in placental tissue. Mutation analysis was performed by sequencing all GLDC, GCSH and AMT exons. RESULTS: CSF glycine (99 micromol/L, reference 3.8-8.0) was already markedly elevated at birth. GCS activity in placental tissue was severely reduced (2.6% of controls). A novel homozygous GLDC c.482A-->G(Y161C) missense mutation was identified. Neonatal hypotonia and apnea did not occur but the long-term outcome was poor, with intractable seizures and severe psychomotor retardation. This contrasts with the favorable outcome with early treatment in variant NKH with mild GCS deficiency (Ann Neuol 2004;56:139-143). INTERPRETATION: Prospective treatment with this regimen can favorably modify the early neonatal course of severe NKH but does not prevent the poor long-term outcome, suggesting glycine-induced prenatal injury and/or ongoing postnatal damage.


Assuntos
Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Glicina Desidrogenase/genética , Hiperglicinemia não Cetótica/tratamento farmacológico , Hiperglicinemia não Cetótica/genética , Ketamina/uso terapêutico , Mutação , Benzoato de Sódio/uso terapêutico , Aldeídos/líquido cefalorraquidiano , Aminoácido Oxirredutases/metabolismo , Proteínas de Transporte/metabolismo , Análise Mutacional de DNA/métodos , Compostos de Epóxi/líquido cefalorraquidiano , Feminino , Seguimentos , Humanos , Hiperglicinemia não Cetótica/líquido cefalorraquidiano , Recém-Nascido , Complexos Multienzimáticos/metabolismo , Estudos Prospectivos , Transferases/metabolismo
13.
J Neurosci ; 25(49): 11479-88, 2005 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-16339041

RESUMO

Individual differences in resiliency to particular stressors may be mediated by specific neuropeptide receptor patterns in the brain. Here, we explored this issue by using a multivariate approach to identify brain sites in which oxytocin (OTR), vasopressin (V1aR), and corticotropin-releasing factor type 1 (CRF1) or type 2 receptor binding covaried with a measure of isolation-induced anxiety: isolation potentiated startle (IPS). Partial least squares (PLS) analysis identified three binding sites, the shell of the nucleus accumbens (AccSh), lateral bed nucleus of the stria terminalis, and intermediate zone of the lateral septum, in which CRF1, V1aR, and OTR receptors, respectively, covaried with IPS. Multiple regression analysis demonstrated that the three binding sites accounted for more of the variation in IPS as a linear combination than when considered individually. Using the same multiple regression model, the linear combination of the same three binding sites/peptide receptors measured in a new group of animals successfully predicted their IPS values. There were no differences in binding between grouped and isolated animals, suggesting that the patterns are trait effects rather than a consequence of isolation. Based on the finding that CRF1 receptors in the AccSh were positively correlated with IPS, we infused CRF directly into the AccSh and found that it significantly potentiated startle after a short isolation period but not under grouped conditions. This result directly supported the predictions made by the combined PLS/regression approach. These results suggest that the integrated activity of neuropeptide systems mediating both social behavior and anxiety underlie IPS.


Assuntos
Prosencéfalo/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Receptores de Ocitocina/metabolismo , Receptores de Vasopressinas/metabolismo , Reflexo de Sobressalto/fisiologia , Isolamento Social , Estimulação Acústica/métodos , Animais , Masculino , Valor Preditivo dos Testes , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley
14.
Mol Genet Metab ; 86(3): 337-43, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16146704

RESUMO

Detection of hepatic carnitine palmitoyltransferase I (CPT IA) deficiency by metabolite screening may be problematic. The urine organic acid profile is generally said to be normal and no abnormal or increased acylcarnitine species are evident on bloodspot tandem MS examination. We diagnosed CPT IA deficiency presenting with acute encephalopathy +/- hypoglycemia and hepatomegaly in one Bukharan Jewish and two Palestinian Arab infants from consanguineous families. CPT1A mutation analysis identified two novel nonsense mutations, c.1737C>A (Y579X) and c.1600delC (L534fsX), extending the known genetic heterogeneity in this disorder. A distinctive organic aciduria was observed in all three patients, even several days after initiation of treatment and resolution of symptoms. Abnormal findings included a hypoketotic dicarboxylic aciduria with prominence of the C12 dicarboxylic (dodecanedioic) acid. This C12 dicarboxylic aciduria suggests that CPT I may play a role in uptake of long-chain dicarboxylic acids by mitochondria after their initial shortening by beta-oxidation in peroxisomes. In addition, increased excretion of 3-hydroxyglutaric acid was detected in all three patients, a finding previously observed only in glutaric aciduria type 1, ketosis, and short-chain hydroxyacyl-CoA dehydrogenase deficiency. Examination of urine organic acids with awareness of these metabolic findings may lead to improved diagnosis of this seemingly rare disorder.


Assuntos
Carnitina O-Palmitoiltransferase/deficiência , Ácidos Dicarboxílicos/metabolismo , Glutaratos/metabolismo , Adulto , Carnitina/análogos & derivados , Carnitina/sangue , Carnitina O-Palmitoiltransferase/genética , Carnitina O-Palmitoiltransferase/metabolismo , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Mutação , Palmitatos
15.
Clin Chem ; 51(3): 610-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15615815

RESUMO

BACKGROUND: Isolated excretion of 2-methylbutyrylglycine (2-MBG) is the hallmark of short/branched-chain acyl-CoA dehydrogenase deficiency (SBCADD), a recently identified defect in the proximal pathway of L-isoleucine oxidation. SBCADD might be underdiagnosed because detection and recognition of urine acylglycines is problematic. Excretion of 2-ethylhydracrylic acid (2-EHA), an intermediate formed in the normally minor R-pathway of L-isoleucine oxidation, has not previously been described in SBCADD. METHODS: Samples from four patients with 2-MBG excretion were analyzed by gas chromatography-mass spectrometry for urine organic acids, quantification of 2-MBG, and chiral determination of 2-methylbutyric acid. Blood-spot acylcarnitines were measured by electrospray-tandem mass spectrometry. Mutations in the ACADSB gene encoding SBCAD were identified by direct sequencing. RESULTS: SBCADD was confirmed in each patient by demonstration of different ACADSB gene mutations. In multiple urine samples, organic acid analysis revealed a prominent 2-EHA peak usually exceeding the size of the 2-MBG peak. Approximately 40-46% of total 2-methylbutyric acid conjugates were in the form of the R-isomer, indicating significant metabolism via the R-pathway. CONCLUSIONS: If, as generally believed, SBCAD is responsible for R-2-MBG dehydrogenation in the R-pathway, 2-EHA would not be produced in SBCADD. Our observation of 2-ethylhydracrylic aciduria in SBCADD implies that a different or alternative enzyme serves this function. Increased flux through the R-pathway may act as a safety valve for overflow of accumulating S-pathway metabolites and thereby mitigate the severity of SBCADD. Awareness of 2-ethylhydracrylic aciduria as a diagnostic marker could lead to increased detection of SBCADD and improved definition of its clinical phenotype.


Assuntos
Butiril-CoA Desidrogenase/deficiência , Glicina/análogos & derivados , Isoleucina/metabolismo , Valeratos/urina , Biomarcadores/urina , Butiratos/química , Butiratos/urina , Butiril-CoA Desidrogenase/genética , Cromatografia Gasosa-Espectrometria de Massas , Glicina/urina , Humanos , Recém-Nascido , Mutação , Oxirredução , Estereoisomerismo
16.
Prenat Diagn ; 24(11): 857-60, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15565656

RESUMO

Hyperargininemia is a progressive neurometabolic disorder caused by deficiency of hepatic cytosolic arginase I, resulting from mutations in the ARG1 gene. We diagnosed arginase deficiency in a three-year-old male child of first-cousin Palestinian Arab parents. Prenatal diagnosis of an unaffected fetus was achieved in the second trimester of a subsequent pregnancy by cordocentesis and analysis of arginase activity in fetal erythrocytes. ARG1 mutation analysis in the proband revealed homozygosity for a deletion of 10,753 bp extending from the first intron to beyond the poly (A) site of the gene. This is the first gross deletion in the ARG1 gene to be identified and the first mutation to be described in an arginase-deficient patient of this ethnic origin. The identification of the ARG1 deletion in this family enabled first-trimester prenatal diagnosis in a subsequent pregnancy by multiplex PCR analysis performed on chorionic villous DNA.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Predisposição Genética para Doença , Hiperargininemia , Diagnóstico Pré-Natal , Adulto , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/genética , Arginase/análise , Pré-Escolar , Diagnóstico Diferencial , Eritrócitos/enzimologia , Feminino , Humanos , Lactente , Masculino , Mutação , Linhagem , Reação em Cadeia da Polimerase , Gravidez , Segundo Trimestre da Gravidez
17.
Ann Neurol ; 56(1): 139-43, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15236413

RESUMO

Three of four nonketotic hyperglycinemia patients homozygous for a novel GLDC mutation (A802V) were treated by assisted respiration and/or sodium benzoate with or without ketamine and had transient neonatal or absent symptoms and normal developmental outcome, despite persisting biochemical evidence of nonketotic hyperglycinemia. This exceptional outcome may be related to the high residual activity of the mutant protein (32% of wild type) and therapeutic intervention during a critical period of heightened brain exposure and sensitivity to glycine.


Assuntos
Aminoácido Oxirredutases/genética , Hiperglicinemia não Cetótica/genética , Hiperglicinemia não Cetótica/fisiopatologia , Mutação Puntual , Adulto , Aminoácido Oxirredutases/metabolismo , Pré-Escolar , Análise Mutacional de DNA , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Feminino , Glicina/metabolismo , Glicina Desidrogenase (Descarboxilante) , Humanos , Hiperglicinemia não Cetótica/diagnóstico , Hiperglicinemia não Cetótica/terapia , Recém-Nascido , Ketamina/uso terapêutico , Espectroscopia de Ressonância Magnética , Masculino , Linhagem , Prognóstico , Respiração Artificial , Benzoato de Sódio/uso terapêutico , Resultado do Tratamento
19.
Mol Genet Metab ; 82(2): 121-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15171999

RESUMO

Virtually all patients with medium-chain acyl-CoA dehydrogenase deficiency (MCADD) are homozygous or compound heterozygous for the 985A > G mutation, which limits the study of a possible genotype/phenotype correlation. A newborn Palestinian infant died suddenly on the second day of life. A previous sibling had also died in similar circumstances aged 3 weeks. Urine organic acid and bloodspot acylcarnitine analysis were consistent with MCADD. He was homozygous for a novel MCAD splice mutation, IVS3-1G > C. This mutation leads to deletion of 7 bp and introduction of a premature termination codon as a result of complete missplicing of MCAD mRNA. This misspliced MCAD mRNA encodes a non-functional protein and is furthermore reduced in amounts due to nonsense-mediated decay, resulting in total lack of functional MCAD enzyme. This is the first molecular identification of MCADD in an Arab patient and the first reported splice mutation in the MCAD gene that has been functionally characterized. The association of homozygosity for a null mutation with lethal neonatal presentation in the index patient and presumably the previous infant suggested a genotype/phenotype correlation. However, a 6-year-old completely asymptomatic sibling also had the characteristic MCADD biochemical phenotype and was homozygous for the same IVS3-1G > C mutation. As a first candidate to modify the disease presentation, by modulating the overlapping enzyme activity, we tested the entire family for the prevalent SCAD gene 625G > A susceptibility variant. Interestingly, all family members were 625G > A homozygous. Additional genetic and/or environmental factors must play a major role in determining the phenotypic diversity of MCADD.


Assuntos
Acil-CoA Desidrogenase/genética , Processamento Alternativo/genética , Carnitina/análogos & derivados , Códon sem Sentido/genética , Homozigoto , Mutação/genética , Morte Súbita do Lactente/genética , Adulto , Árabes/genética , Sequência de Bases , Carnitina/sangue , Criança , Feminino , Humanos , Recém-Nascido , Masculino , Oxirredução , Linhagem , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Morte Súbita do Lactente/sangue
20.
J Neurol Sci ; 218(1-2): 53-8, 2004 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-14759633

RESUMO

Hyperornithinemia, hyperammonemia, and homocitrullinuria (HHH) syndrome is caused by mutations in the SLC25A15 (ORNT1) gene encoding the mitochondrial ornithine transporter, but the mechanism of pathogenesis of the encephalopathy, spastic paraparesis and hepatopathy remains undetermined. HHH syndrome was diagnosed in a 2-year-old Palestinian boy with developmental delay and seizures, and subsequently in his 13-year-old brother with developmental delay. Direct sequencing of the PCR products of SLC25A15 exon amplifications revealed that both brothers were homozygous for a novel 446G deletion in exon 3 as well as for a 760A>T (I254L) polymorphism in exon 5, which is downstream of a premature termination codon produced by the frameshift resulting from the 446G deletion. The index patient had elevated liver enzymes as well as hyperalaninemia, lactic acidemia with an elevated lactate to pyruvate ratio, and increased urinary excretion of lactate, glutarate and Krebs cycle intermediates. These findings are indicative of mitochondrial dysfunction and are in accordance with ultrastructural studies showing increased numbers of large and bizarre mitochondria in liver, muscle, leukocytes and fibroblasts of some HHH patients. Neurologic and hepatic manifestations are characteristic of some primary mitochondrial disorders. Secondary mitochondrial dysfunction may contribute to the pathogenesis of these same features in HHH syndrome.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Citrulina/análogos & derivados , Doenças Mitocondriais/genética , Mutação , Proteínas/genética , Adolescente , Alanina/metabolismo , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Sistemas de Transporte de Aminoácidos Básicos , Árabes/etnologia , Pré-Escolar , Citrulina/genética , Citrulina/metabolismo , Citrulina/urina , Análise Mutacional de DNA , Éxons , Saúde da Família , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glicina/genética , Humanos , Hiperamonemia/genética , Ácido Láctico/metabolismo , Masculino , Doenças Mitocondriais/complicações , Proteínas de Transporte da Membrana Mitocondrial , Ornitina/sangue , Ornitina/metabolismo , Reação em Cadeia da Polimerase/métodos
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