RESUMO
Aromatic amino acid decarboxylases (AAADs) are pyridoxal-5'-phosphate (PLP)-dependent enzymes that catalyze the decarboxylation of aromatic amino acid l-amino acids. In plants, apart from canonical AAADs that catalyze the straightforward decarboxylation reaction, other members of the AAAD family function as aromatic acetaldehyde synthases (AASs) and catalyze more complex decarboxylation-dependent oxidative deamination. The interconversion between a canonical AAAD and an AAS can be achieved by a single tyrosine-phenylalanine mutation in the large catalytic loop of the enzymes. In this work, we report implicit ligand sampling (ILS) calculations of the canonical l-tyrosine decarboxylase from Papaver somniferum (PsTyDC) that catalyzes l-tyrosine decarboxylation and its Y350F mutant that instead catalyzes the decarboxylation-dependent oxidative deamination of the same substrate. Through comparative analysis of the resulting three-dimensional (3D) O2 free energy profiles, we evaluate the impact of the key tyrosine/phenylalanine mutation on oxygen accessibility to both the wild type and Y350F mutant of PsTyDC. Additionally, using molecular dynamics (MD) simulations of the l-tryptophan decarboxylase from Catharanthus roseus (CrTDC), we further investigate the dynamics of a large catalytic loop known to be indispensable to all AAADs. Results of our ILS and MD calculations shed new light on how key structural elements and loop conformational dynamics underlie the enzymatic functions of different members of the plant AAAD family.
Assuntos
Descarboxilases de Aminoácido-L-Aromático , Domínio Catalítico , Simulação de Dinâmica Molecular , Oxigênio , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/química , Oxigênio/metabolismo , Oxigênio/química , Papaver/enzimologia , Papaver/genética , Papaver/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Tirosina/metabolismo , Tirosina/química , Tirosina/genéticaRESUMO
INTRODUCTION: In gene therapy with adeno-associated virus (AAV) vectors for diseases of the central nervous system, the vectors can be administered into blood vessels, cerebrospinal fluid space, or the brain parenchyma. When gene transfer to a large area of the brain is required, the first two methods are used, but for diseases in which local gene transfer is expected to be effective, vectors are administered directly into the brain parenchyma. AREAS COVERED: Strategies for intraparenchymal vector delivery in gene therapy for Parkinson's disease, aromatic l-amino acid decarboxylase (AADC) deficiency, and epilepsy are reviewed. EXPERT OPINION: Stereotactic intraparenchymal injection of AAV vectors allows precise gene delivery to the target site. Although more surgically invasive than intravascular or intrathecal administration, intraparenchymal vector delivery has the advantage of a lower vector dose, and preexisting neutralizing antibodies have little effect on the transduction efficacy. This approach improves motor function in AADC deficiency and led to regulatory approval of an AAV vector for the disease in the EU. Although further validation through clinical studies is needed, direct infusion of viral vectors into the brain parenchyma is expected to be a novel treatment for Parkinson's disease and drug-resistant epilepsy.
Assuntos
Dependovirus , Terapia Genética , Vetores Genéticos , Humanos , Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos/genética , Animais , Doença de Parkinson/terapia , Doença de Parkinson/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/terapia , Técnicas de Transferência de Genes , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/deficiência , Erros Inatos do Metabolismo dos AminoácidosRESUMO
Orthostatic hypotension (OH) is a common condition. Many potential etiologies of OH have been identified, but in clinical practice the underlying cause of OH is often unknown. In the present study, we identified a novel and extraordinary etiology of OH. We describe a first case of acquired severe OH with syncope, and the female patient had extremely low levels of catecholamines and serotonin in plasma, urine and cerebrospinal fluid (CSF). Her clinical and biochemical evidence showed a deficiency of the enzyme aromatic l-amino acid decarboxylase (AADC), which converts l-DOPA to dopamine, and 5-hydroxytryptophan to serotonin, respectively. The consequence of pharmacologic stimulation of catecholaminergic nerves and radionuclide examination revealed her catecholaminergic nerves denervation. Moreover, we found that the patient's serum showed presence of autoantibodies against AADC, and that isolated peripheral blood mononuclear cells (PBMCs) from the patient showed cytokine-induced toxicity against AADC. These observations suggest that her autoimmunity against AADC is highly likely to cause toxicity to adrenal medulla and catecholaminergic nerves which contain AADC, resulting in hypocatecholaminemia and severe OH. Administration of vitamin B6, an essential cofactor of AADC, enhanced her residual AADC activity and drastically improved her symptoms. Our data thus provide a new insight into pathogenesis and pathophysiology of OH.
Assuntos
Descarboxilases de Aminoácido-L-Aromático , Autoimunidade , Hipotensão Ortostática , Feminino , Humanos , Pessoa de Meia-Idade , Descarboxilases de Aminoácido-L-Aromático/deficiência , Autoanticorpos/sangue , Autoanticorpos/imunologia , Catecolaminas , Dopamina/metabolismo , Hipotensão Ortostática/etiologia , Hipotensão Ortostática/fisiopatologia , Serotonina/metabolismoRESUMO
A 7-year-old girl presented with persistent anxiety symptoms for several years following gene therapy for an ultrarare neurometabolic disorder (aromatic L-amino acid decarboxylase [AADC] deficiency). AADC is the final enzyme in the monoamine synthesis pathway (Figure 1).1 Its absence results in a severe combined deficiency in serotonin, dopamine, epinephrine, and norepinephrine, causing significant developmental delays, hypotonia, and dystonia. The incidence of AADC deficiency is estimated at â¼1 in 500,000,2 and â¼200 cases have been described.1 Recently available disease-modifying gene therapy for this condition dramatically improves motor symptoms, and received regulatory approval in some regions in 2022.2 There are no data to guide psychiatric care post gene therapy for AADC or other neurologic disorders to date.3.
Assuntos
Descarboxilases de Aminoácido-L-Aromático , Terapia Genética , Inibidores Seletivos de Recaptação de Serotonina , Humanos , Feminino , Criança , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Descarboxilases de Aminoácido-L-Aromático/deficiência , Descarboxilases de Aminoácido-L-Aromático/genética , Terapia Genética/métodos , Erros Inatos do Metabolismo dos Aminoácidos/genética , Erros Inatos do Metabolismo dos Aminoácidos/terapiaRESUMO
Parkinson's disease (PD) starts at the molecular and cellular level long before motor symptoms appear, yet there are no early-stage molecular biomarkers for diagnosis, prognosis prediction, or monitoring therapeutic response. This lack of biomarkers greatly impedes patient care and translational research-L-DOPA remains the standard of care more than 50 years after its introduction. Here, we performed a large-scale, multi-tissue, and multi-platform proteomics study to identify new biomarkers for early diagnosis and disease monitoring in PD. We analyzed 4877 cerebrospinal fluid, blood plasma, and urine samples from participants across seven cohorts using three orthogonal proteomics methods: Olink proximity extension assay, SomaScan aptamer precipitation assay, and liquid chromatography-mass spectrometry proteomics. We discovered that hundreds of proteins were upregulated in the CSF, blood, or urine of PD patients, prodromal PD patients with DAT deficit and REM sleep behavior disorder or anosmia, and non-manifesting genetic carriers of LRRK2 and GBA mutations. We nominate multiple novel hits across our analyses as promising markers of early PD, including DOPA decarboxylase (DDC), also known as L-aromatic acid decarboxylase (AADC), sulfatase-modifying factor 1 (SUMF1), dipeptidyl peptidase 2/7 (DPP7), glutamyl aminopeptidase (ENPEP), WAP four-disulfide core domain 2 (WFDC2), and others. DDC, which catalyzes the final step in dopamine synthesis, particularly stands out as a novel hit with a compelling mechanistic link to PD pathogenesis. DDC is consistently upregulated in the CSF and urine of treatment-naïve PD, prodromal PD, and GBA or LRRK2 carrier participants by all three proteomics methods. We show that CSF DDC levels correlate with clinical symptom severity in treatment-naïve PD patients and can be used to accurately diagnose PD and prodromal PD. This suggests that urine and CSF DDC could be a promising diagnostic and prognostic marker with utility in both clinical care and translational research.
Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Dopa Descarboxilase/genética , Proteômica , Biomarcadores/líquido cefalorraquidiano , Plasma/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Descarboxilases de Aminoácido-L-AromáticoRESUMO
BACKGROUND: Aromatic l-amino acid decarboxylase deficiency (AADCD) is a rare, autosomal-recessive neurometabolic disorder caused by variants in dopa decarboxylase (DDC) gene, resulting in a severe combined deficiency of serotonin, dopamine, norepinephrine, and epinephrine. Birth prevalence of AADCD varies by population. In pilot studies, 3-O-methyldopa (3-OMD) was shown to be a reliable biomarker for AADCD in high-throughput newborn screening (NBS) allowing an early diagnosis and access to gene therapy. To evaluate the usefulness of this method for routine NBS, 3-OMD screening results from the largest three German NBS centers were analyzed. METHODS: A prospective, multicenter (n = 3) NBS pilot study evaluated screening for AADCD by quantifying 3-OMD in dried blood spots (DBS) using tandem mass spectrometry (MS/MS). RESULTS: In total, 766,660 neonates were screened from January 2021 until June 2023 with 766,647 with unremarkable AADCD NBS (766,443 by 1st-tier analysis and 204 by 2nd-tier analysis) and 13 with positive NBS result recalled for confirmatory diagnostics (recall-rate about 1:59,000). Molecular genetic analysis confirmed AADCD (c.79C > T p.[Arg27Cys] in Exon 2 und c.215 A > C p.[His72Pro] in Exon 3) in one infant. Another individual was highly suspected with AADCD but died before confirmation (overall positive predictive value 0.15). False-positive results were caused by maternal L-Dopa use (n = 2) and prematurity (30th and 36th week of gestation, n = 2). However, in 63% (n = 7) the underlying etiology for false positive results remained unexplained. Estimated birth prevalence (95% confidence interval) was 1:766,660 (95% CI 1:775,194; 1:769,231) to 1:383,330 (95% CI 1:384,615; 1:383,142). The identified child remained asymptomatic until last follow up at the age of 9 months. CONCLUSIONS: The proposed screening strategy with 3-OMD detection in DBS is feasible and effective to identify individuals with AADCD. The estimated birth prevalence supports earlier estimations and confirms AADCD as a very rare disorder. Pre-symptomatic identification by NBS allows a disease severity adapted drug support to diminish clinical complications until individuals are old enough for the application of the gene therapy.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Descarboxilases de Aminoácido-L-Aromático/deficiência , Espectrometria de Massas em Tandem , Lactente , Recém-Nascido , Criança , Humanos , Triagem Neonatal/métodos , Projetos Piloto , Prevalência , Estudos Prospectivos , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/epidemiologia , Erros Inatos do Metabolismo dos Aminoácidos/genéticaAssuntos
Erros Inatos do Metabolismo dos Aminoácidos , Descarboxilases de Aminoácido-L-Aromático/deficiência , Doenças Metabólicas , Humanos , Prevalência , Erros Inatos do Metabolismo dos Aminoácidos/epidemiologia , Erros Inatos do Metabolismo dos Aminoácidos/genética , Erros Inatos do Metabolismo dos Aminoácidos/metabolismoRESUMO
Parkinson's disease (PD) is a neurodegenerative illness characterized by specific loss of dopaminergic neurons, resulting in impaired motor movement. Its prevalence is twice as compared to the previous 25 years and affects more than 10 million individuals. Lack of treatment still uses levodopa and other options as disease management measures. Treatment shifts to gene therapy (GT), which utilizes direct delivery of specific genes at the targeted area. Therefore, the use of aromatic L-amino acid decarboxylase (AADC) and glial-derived neurotrophic factor (GDNF) therapy achieves an effective control to treat PD. Patients diagnosed with PD may experience improved therapeutic outcomes by reducing the frequency of drug administration while utilizing provasin and AADC as dopaminergic protective therapy. Enhancing the enzymatic activity of tyrosine hydroxylase (TH), glucocorticoid hormone (GCH), and AADC in the striatum would be useful for external L-DOPA to restore the dopamine (DA) level. Increased expression of glutamic acid decarboxylase (GAD) in the subthalamic nucleus (STN) may also be beneficial in PD. Targeting GDNF therapy specifically to the putaminal region is clinically sound and beneficial in protecting the dopaminergic neurons. Furthermore, preclinical and clinical studies supported the role of GDNF in exhibiting its neuroprotective effect in neurological disorders. Another Ret receptor, which belongs to the tyrosine kinase family, is expressed in dopaminergic neurons and sounds to play a vital role in inhibiting the advancement of PD. GDNF binding on those receptors results in the formation of a receptor-ligand complex. On the other hand, venous delivery of recombinant GDNF by liposome-based and encapsulated cellular approaches enables the secure and effective distribution of neurotrophic factors into the putamen and parenchyma. The current review emphasized the rate of GT target GDNF and AADC therapy, along with the corresponding empirical evidence.
Assuntos
Descarboxilases de Aminoácido-L-Aromático , Terapia Genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Doença de Parkinson , Putamen , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/terapia , Descarboxilases de Aminoácido-L-Aromático/genética , Terapia Genética/métodos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/uso terapêutico , Putamen/metabolismo , Animais , Levodopa/uso terapêutico , Dopamina/metabolismoRESUMO
Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare genetic disorder of monoamine neurotransmitter synthesis that presents with a range of symptoms, including motor dysfunction and limited attainment of developmental motor milestones. The approval of eladocagene exuparvovec, a gene therapy for AADC deficiency with demonstrated efficacy for motor improvements, now expands the range of motor outcomes possible for patients with this disorder. However, recommendations and guidelines for therapy following treatment with gene therapy are lacking. To ensure patients can reach their full potential following treatment with gene therapy, it is essential they receive rehabilitation therapies designed specifically with their impairments and goals in mind. Therefore, we highlight specific rehabilitative needs of patients following gene therapy and propose a set of recommendations for the post-treatment period based on collective experiences of therapists, physicians, and caregivers treating and caring for patients with AADC deficiency who have been treated with gene therapy. These recommendations include a focus on periods of intensive therapy, facilitating active movements, training for functional abilities, cognitive and communication training, parent/caregiver empowerment, collaboration between therapists and caregivers to develop in-home programs, and the incorporation of supplemental forms of therapy that patients and their families may find more enjoyable and engaging. Many of these rehabilitative strategies may be employed prior to gene therapy. However, these recommendations will be valuable for therapists, caregivers, and wider treatment teams as they prepare for the post-treatment journey with these patients. Furthermore, the considerations and recommendations presented here may prove beneficial outside the AADC deficiency community as gene therapies and other treatments are developed and approved for other rare diseases.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Humanos , Erros Inatos do Metabolismo dos Aminoácidos/genética , Erros Inatos do Metabolismo dos Aminoácidos/terapia , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Descarboxilases de Aminoácido-L-Aromático/genética , Terapia Genética , AminoácidosRESUMO
The ancient anti-alcohol drug disulfiram (DSF) has gained widespread attention for its highly effective anti-tumor effects in cancer treatment. Our previous studies have developed liposome of Cu (DDC)2 to overcome the limitations, like the poor water solubility. However, Cu (DDC)2 liposomes still have shown difficulties in severe hemolytic reactions at high doses and systemic toxicity, which have limited their clinical use. Therefore, this study aims to exploratively investigate the feasibility of using DSF or DDC in combination also can chelate Zn2+ to form zinc diethyldithiocarbamate (Zn (DDC)2). Furthermore, this study prepared stable and homogeneous Zn (DDC)2 liposomes, which were able to be released in the tumor microenvironment (TME). The released Zn (DDC)2 was converted to Cu (DDC)2 with the help of endogenous Cu2+-switch enriched in the TME, which has a higher stability constant compared with Zn (DDC)2. In other words, the Cu2+-switch is activated at the tumor site, completing the conversion of the less cytotoxic Zn (DDC)2 to the more cytotoxic Cu (DDC)2 for effective tumor therapy so that the Zn (DDC)2 liposomes in vivo achieved the comparable therapeutic efficacy and provided a safer alternative to Cu (DDC)2 liposomes in cancer therapy.
Assuntos
Antineoplásicos , Neoplasias , Humanos , Lipossomos/uso terapêutico , Ditiocarb/uso terapêutico , Dissulfiram , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Zinco , Cobre/uso terapêutico , Microambiente Tumoral , Descarboxilases de Aminoácido-L-Aromático/uso terapêuticoRESUMO
Aromatic l-amino acid decarboxylase (AADC) deficiency is an autosomal recessive neurotransmitter disorder caused by pathogenic DOPA decarboxylase (DDC) variants. We previously reported Japanese siblings with AADC deficiency, which was confirmed by the lack of enzyme activity; however, only a heterozygous missense variant was detected. We therefore performed targeted long-read sequencing by adaptive sampling to identify any missing variants. Haplotype phasing and variant calling identified a novel deep intronic variant (c.714+255 C > A), which was predicted to potentially activate the noncanonical splicing acceptor site. Minigene assay revealed that wild-type and c.714+255 C > A alleles had different impacts on splicing. Three transcripts, including the canonical transcript, were detected from the wild-type allele, but only the noncanonical cryptic exon was produced from the variant allele, indicating that c.714+255 C > A was pathogenic. Target long-read sequencing may be used to detect hidden pathogenic variants in unresolved autosomal recessive cases with only one disclosed hit variant.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Descarboxilases de Aminoácido-L-Aromático/deficiência , Dopa Descarboxilase , Humanos , Dopa Descarboxilase/genética , Erros Inatos do Metabolismo dos Aminoácidos/genética , Íntrons , Mutação de Sentido IncorretoRESUMO
5-Hydroxytryptamine (5-HT) and its derivative bufotenine, which possess important physiological functions, are the primary active components in the secretions of toad parotid and skin gland. However, the biosynthetic pathway of these substances remains unclear in toads. To characterize toad's Aromatic-L-amino-acid decarboxylase (AADC), the key enzyme in the predicted 5-HT derivatives biosynthetic pathway, the full-length cDNA of AADC from Bufo bufo gargarizans (BbgAADC) was cloned from the parotoid gland of B. bufo gargarizans. The recombinant BbgAADC exhibited optimal expression in E. coli BL21 (DE3) containing pCold-BbgAADC after induction for 16 h at 15 °C with 0.3 mM IPTG, resulting in substantial yields of soluble proteins. The enzymological properties of BbgAADC were assessed, and it was determined that the optimal reaction temperature was 37 °C, the optimal pH was 8.6, and the optimum molar ratio of pyridoxal-5'-phosphate (PLP) to BbgAADC was found to be 3.6:1. Additionally, high substrate specificity was observed, as BbgAADC could catalyze the production of 5-HT from 5-hydroxytryptophan (5-HTP) but not dopamine or tryptamine from levodopa or tryptophan, respectively. The Km of the recombinant protein BbgAADC was 0.2918 mM and the maximum reaction rate (Vmax) was 1.182 µM·min-1 when 5-HTP was used as substrate. The Kcat was 0.0545 min-1, and Kcat/Km was 0.1868 mM-1·min-1. To elucidate the mechanism of BbgAADC, molecular docking was performed with PLP and 5-HTP, or the external aldimine formed by 5-HTP and PLP. The results indicated that the active sites for BbgAADC to bind with PLP were K303, H192, N300, A148, F309, T246, A273, and T147. W71, Y79, F80, P81, T82, H192, T246, N300, H302, F309, and R477 served as catalytically active sites for the binding of BbgAADC to 5-HTP. Furthermore, R447, W71, S149, N300, A148, and T147 of BbgAADC were involved in the decarboxylation reaction of the aldimine formed by PLP and 5-HTP.
Assuntos
5-Hidroxitriptofano , Bufo bufo , Animais , Bufo bufo/metabolismo , 5-Hidroxitriptofano/genética , 5-Hidroxitriptofano/metabolismo , Serotonina/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Simulação de Acoplamento Molecular , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Bufonidae/metabolismo , Clonagem MolecularRESUMO
Aromatic L-amino acid decarboxylase deficiency (AADCd) is a rare autosomal recessive neurometabolic disorder caused by AADC deficiency, an enzyme encoded by the DDC gene. Since the enzyme is involved in the biosynthesis of serotonin and dopamine, its deficiency determines the lack of these neurotransmitters, but also of norepinephrine and epinephrine. Onset is early and the key signs are hypotonia, movement disorders (oculogyric crises, dystonia and hypokinesia), developmental delay and autonomic dysfunction. Taiwan is the site of a potential founder variant (IVS6+4A>T) with a predicted incidence of 1/32,000 births, while only 261 patients with this deficit have been described worldwide. Actually, the number of affected persons could be greater, given that the spectrum of clinical manifestations is broad and still little known. In our study we selected 350 unrelated patients presenting with different neurological disorders including heterogeneous neuromuscular disorders, cognitive deficit, behavioral disorders and autism spectrum disorder, for which the underlying etiology had not yet been identified. Molecular investigation of the DDC gene was carried out with the aim of identifying affected patients and/or carriers. Our study shows a high frequency of carriers (2.57%) in Sicilian subjects with neurological deficits, with a higher concentration in northern and eastern Sicily. Assuming these data as representative of the general Sicilian population, the risk may be comparable to some rare diseases included in the newborn screening programs such as spinal muscular atrophy, cystic fibrosis and phenylketonuria.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Transtorno do Espectro Autista , Doenças do Sistema Nervoso , Recém-Nascido , Humanos , Transtorno do Espectro Autista/genética , Descarboxilases de Aminoácido-L-Aromático/genética , Doenças do Sistema Nervoso/genética , Testes GenéticosRESUMO
Inborn errors of neurotransmitter (NT) metabolism are a group of rare, heterogenous diseases with predominant neurological features, such as movement disorders, autonomic dysfunction, and developmental delay. Clinical overlap with other disorders has led to delayed diagnosis and treatment, and some conditions are refractory to oral pharmacotherapies. Gene therapies have been developed and translated to clinics for paediatric inborn errors of metabolism, with 38 interventional clinical trials ongoing to date. Furthermore, efforts in restoring dopamine synthesis and neurotransmission through viral gene therapy have been developed for Parkinson's disease. Along with the recent European Medicines Agency (EMA) and Medicines and Healthcare Products Regulatory Agency (MHRA) approval of an AAV2 gene supplementation therapy for AADC deficiency, promising efficacy and safety profiles can be achieved in this group of diseases. In this review, we present preclinical and clinical advances to address NT-related diseases, and summarise potential challenges that require careful considerations for NT gene therapy studies.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Doença de Parkinson , Humanos , Criança , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Descarboxilases de Aminoácido-L-Aromático , Terapia Genética , NeurotransmissoresRESUMO
Childhood demyelinative diseases classification (DDC) with brain magnetic resonance imaging (MRI) is crucial to clinical diagnosis. But few attentions have been paid to DDC in the past. How to accurately differentiate pediatric-onset neuromyelitis optica spectrum disorder (NMOSD) from acute disseminated encephalomyelitis (ADEM) based on MRI is challenging in DDC. In this paper, a novel architecture M-DDC based on joint U-Net segmentation network and deep convolutional network is developed. The U-Net segmentation can provide pixel-level structure information, that helps the lesion areas location and size estimation. The classification branch in DDC can detect the regions of interest inside MRIs, including the white matter regions where lesions appear. The performance of the proposed method is evaluated on MRIs of 201 subjects recorded from the Children's Hospital of Zhejiang University School of Medicine. The comparisons show that the proposed DDC achieves the highest accuracy of 99.19% and dice of 71.1% for ADEM and NMOSD classification and segmentation, respectively.
Assuntos
Imageamento por Ressonância Magnética , Neuromielite Óptica , Criança , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Neuromielite Óptica/diagnóstico por imagem , Neuromielite Óptica/patologia , Processamento de Imagem Assistida por Computador/métodos , Descarboxilases de Aminoácido-L-AromáticoRESUMO
OBJECTIVES: Electronic health record (EHR) data may facilitate the identification of rare diseases in patients, such as aromatic l-amino acid decarboxylase deficiency (AADCd), an autosomal recessive disease caused by pathogenic variants in the dopa decarboxylase gene. Deficiency of the AADC enzyme results in combined severe reductions in monoamine neurotransmitters: dopamine, serotonin, epinephrine, and norepinephrine. This leads to widespread neurological complications affecting motor, behavioral, and autonomic function. The goal of this study was to use EHR data to identify previously undiagnosed patients who may have AADCd without available training cases for the disease. MATERIALS AND METHODS: A multiple symptom and related disease annotated dataset was created and used to train individual concept classifiers on annotated sentence data. A multistep algorithm was then used to combine concept predictions into a single patient rank value. RESULTS: Using an 8000-patient dataset that the algorithms had not seen before ranking, the top and bottom 200 ranked patients were manually reviewed for clinical indications of performing an AADCd diagnostic screening test. The top-ranked patients were 22.5% positively assessed for diagnostic screening, with 0% for the bottom-ranked patients. This result is statistically significant at P < .0001. CONCLUSION: This work validates the approach that large-scale rare-disease screening can be accomplished by combining predictions for relevant individual symptoms and related conditions which are much more common and for which training data is easier to create.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Descarboxilases de Aminoácido-L-Aromático/deficiência , Processamento de Linguagem Natural , Doenças Raras , Humanos , Dopamina , Aprendizado de MáquinaRESUMO
Uterine corpus endometrial carcinoma (UCEC) is infiltrated by immune cells, which are involved in the growth and proliferation of malignant tumors and resistance to immunotherapy. This study suggested that RNA modification regulators played an important role in the development and prognosis of UCEC. Many studies confirmed that RNA modification played an essential role in tumor immune regulation, and abnormal RNA modification contributed to tumorigenesis and cancer progression. Based on the RNA modification regulatory factors, the UCEC samples from TCGA (The Cancer Genome Atlas) were classified into two clusters, namely Cluster A and Cluster B, using unsupervised consensus clustering. We obtained DEG (differentially expressed genes) between the two clusters, and constructed a risk model of RNA modification-related genes using DEGs. Cluster A had lower RNA modification regulatory factors, richer immune cell infiltration, and better prognosis. The differentially expressed genes between the two clusters were obtained, and these genes were used for modeling. This model divided patients with UCEC into two groups. The low-risk group had better immune infiltration, and the ROC (receiver operating characteristic) curve showed that this model had good predictive efficacy. The low-risk group had a better response to immunotherapy by immune checkpoint prediction. We obtained the key gene L-dopa decarboxylase (DDC) through the intersection of LASSO model genes and GEO dataset GSE17025. We evaluated the potential biological functions of DDC. The differences in the expression of DDC were verified by immunohistochemistry. We evaluated the relationship between DDC and immune cell infiltration and verified this difference using immunofluorescence. Cluster A with low expression of RNA modification regulators has better prognosis and richer immune cell infiltration, therefore, we believed that RNA modification regulators in UCEC were closely related to the tumor microenvironment. Also, the risk score could well predict the prognosis of patients and guide immunotherapy, which might benefit patients with UCEC.
Assuntos
Carcinoma Endometrioide , Neoplasias do Endométrio , Humanos , Feminino , Microambiente Tumoral/genética , Neoplasias do Endométrio/genética , Prognóstico , RNA , Descarboxilases de Aminoácido-L-AromáticoRESUMO
Screenings of cheese isolates revealed that the Latilactobacillus curvatus strain FAM25164 formed tryptamine and tyramine. In the present study, it was studied whether a tryptophan decarboxylase, which has rarely been described in bacteria, could be involved in the production of tryptamine. The genome of strain FAM25164 was sequenced and two amino acid decarboxylase genes of interest were identified by sequence comparisons and gene context analyses. One of the two genes, named tdc1, showed 99% identity to the tdcA gene that has recently been demonstrated by knockout studies to play a role in tyramine formation in L. curvatus. The second gene, named tdc2, was predicted to have an amino acid decarboxylase function, but could not be assigned to a metabolic function. Its protein sequence has 51% identity with Tdc1 and the tdc2 gene is part of a gene cluster not often found in publicly available genome sequences of L. curvatus. Among others, the gene cluster includes a tryptophan-tRNA ligase, indicating that tdc2 plays a role in tryptophan metabolism. To study decarboxylase activity, tdc1 and tdc2 were cloned and expressed as His6-tagged proteins in Escherichia coli. The recombinant E. coli expressing tdc1 produced tyramine, whereas E. coli expressing tdc2 produced tryptamine. The purified recombinant Tdc1 protein decarboxylated tyrosine and 2,3-dihydroxy-l-phenylalanine (l-DOPA), but not tryptophan and phenylalanine. In contrast, the purified Tdc2 was capable of decarboxylating tryptophan but not l-DOPA, tyrosine, or phenylalanine. This study describes a novel bacterial tryptophan decarboxylase (EC 4.1.1.105) that may be responsible for tryptamine formation in cheese.