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1.
Cell ; 154(3): 505-17, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23911318

RESUMO

Purine biosynthesis and metabolism, conserved in all living organisms, is essential for cellular energy homeostasis and nucleic acid synthesis. The de novo synthesis of purine precursors is under tight negative feedback regulation mediated by adenosine and guanine nucleotides. We describe a distinct early-onset neurodegenerative condition resulting from mutations in the adenosine monophosphate deaminase 2 gene (AMPD2). Patients have characteristic brain imaging features of pontocerebellar hypoplasia (PCH) due to loss of brainstem and cerebellar parenchyma. We found that AMPD2 plays an evolutionary conserved role in the maintenance of cellular guanine nucleotide pools by regulating the feedback inhibition of adenosine derivatives on de novo purine synthesis. AMPD2 deficiency results in defective GTP-dependent initiation of protein translation, which can be rescued by administration of purine precursors. These data suggest AMPD2-related PCH as a potentially treatable early-onset neurodegenerative disease.


Assuntos
AMP Desaminase/metabolismo , Atrofias Olivopontocerebelares/metabolismo , Purinas/biossíntese , AMP Desaminase/química , AMP Desaminase/genética , Animais , Tronco Encefálico/patologia , Cerebelo/patologia , Criança , Feminino , Guanosina Trifosfato/metabolismo , Humanos , Masculino , Camundongos , Camundongos Knockout , Mutação , Células-Tronco Neurais/metabolismo , Atrofias Olivopontocerebelares/genética , Atrofias Olivopontocerebelares/patologia , Biossíntese de Proteínas , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo
2.
Pharm Res ; 40(11): 2555-2566, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37442882

RESUMO

INTRODUCTION: The unbound brain extracelullar fluid (brainECF) to plasma steady state partition coefficient, Kp,uu,BBB, values provide steady-state information on the extent of blood-brain barrier (BBB) transport equilibration, but not on pharmacokinetic (PK) profiles seen by the brain targets. Mouse models are frequently used to study brain PK, but this information cannot directly be used to inform on human brain PK, given the different CNS physiology of mouse and human. Physiologically based PK (PBPK) models are useful to translate PK information across species. AIM: Use the LeiCNS-PK3.0 PBPK model, to predict brain extracellular fluid PK in mice. METHODS: Information on mouse brain physiology was collected from literature. All available connected data on unbound plasma, brainECF PK of 10 drugs (cyclophosphamide, quinidine, erlotonib, phenobarbital, colchicine, ribociclib, topotecan, cefradroxil, prexasertib, and methotrexate) from different mouse strains were used. Dosing regimen dependent plasma PK was modelled, and Kpuu,BBB values were estimated, and provided as input into the LeiCNS-PK3.0 model to result in prediction of PK profiles in brainECF. RESULTS: Overall, the model gave an adequate prediction of the brainECF PK profile for 7 out of the 10 drugs. For 7 drugs, the predicted versus observed brainECF data was within two-fold error limit and the other 2 drugs were within five-fold error limit. CONCLUSION: The current version of the mouse LeiCNS-PK3.0 model seems to reasonably predict available information on brainECF from healthy mice for most drugs. This brings the translation between mouse and human brain PK one step further.


Assuntos
Líquido Extracelular , Modelos Biológicos , Humanos , Barreira Hematoencefálica , Encéfalo , Farmacocinética , Quinidina , Animais , Camundongos
3.
Pharm Res ; 39(7): 1343-1361, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35258766

RESUMO

Micrometastatic brain tumor cells, which cause recurrence of malignant brain tumors, are often protected by the intact blood-brain barrier (BBB). Therefore, it is essential to deliver effective drugs across not only the disrupted blood-tumor barrier (BTB) but also the intact BBB to effectively treat malignant brain tumors. Our aim is to predict pharmacokinetic (PK) profiles in brain tumor regions with the disrupted BTB and the intact BBB to support the successful drug development for malignant brain tumors. LeiCNS-PK3.0, a comprehensive central nervous system (CNS) physiologically based pharmacokinetic (PBPK) model, was extended to incorporate brain tumor compartments. Most pathophysiological parameters of brain tumors were obtained from literature and two missing parameters of the BTB, paracellular pore size and expression level of active transporters, were estimated by fitting existing data, like a "handshake". Simultaneous predictions were made for PK profiles in extracellular fluids (ECF) of brain tumors and normal-appearing brain and validated on existing data for six small molecule anticancer drugs. The LeiCNS-tumor model predicted ECF PK profiles in brain tumor as well as normal-appearing brain in rat brain tumor models and high-grade glioma patients within twofold error for most data points, in combination with estimated paracellular pore size of the BTB and active efflux clearance at the BTB. Our model demonstrated a potential to predict PK profiles of small molecule drugs in brain tumors, for which quantitative information on pathophysiological alterations is available, and contribute to the efficient and successful drug development for malignant brain tumors.


Assuntos
Neoplasias Encefálicas , Glioma , Animais , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Ratos
4.
Pharm Res ; 39(7): 1303-1319, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35606598

RESUMO

BACKGROUND: Very little knowledge exists on the impact of Alzheimer's disease on the CNS target site pharmacokinetics (PK). AIM: To predict the CNS PK of cognitively healthy young and elderly and of Alzheimer's patients using the physiologically based LeiCNS-PK3.0 model. METHODS: LeiCNS-PK3.0 was used to predict the PK profiles in brain extracellular (brainECF) and intracellular (brainICF) fluids and cerebrospinal fluid of the subarachnoid space (CSFSAS) of donepezil, galantamine, memantine, rivastigmine, and semagacestat in young, elderly, and Alzheimer's patients. The physiological parameters of LeiCNS-PK3.0 were adapted for aging and Alzheimer's based on an extensive literature search. The CNS PK profiles at plateau for clinical dose regimens were related to in vitro IC50 values of acetylcholinesterase, butyrylcholinesterase, N-methyl-D-aspartate, or gamma-secretase. RESULTS: The PK profiles of all drugs differed between the CNS compartments regarding plateau levels and fluctuation. BrainECF, brainICF and CSFSAS PK profile relationships were different between the drugs. Aging and Alzheimer's had little to no impact on CNS PK. Rivastigmine acetylcholinesterase IC50 values were not reached. Semagacestat brain PK plateau levels were below the IC50 of gamma-secretase for half of the interdose interval, unlike CSFSAS PK profiles that were consistently above IC50. CONCLUSION: This study provides insights into the relations between CNS compartments PK profiles, including target sites. CSFSAS PK appears to be an unreliable predictor of brain PK. Also, despite extensive changes in blood-brain barrier and brain properties in Alzheimer's, this study shows that the impact of aging and Alzheimer's pathology on CNS distribution of the five drugs is insignificant.


Assuntos
Doença de Alzheimer , Acetilcolinesterase , Idoso , Envelhecimento , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide , Encéfalo , Butirilcolinesterase , Inibidores da Colinesterase/farmacocinética , Humanos , Indanos/farmacocinética , Piperidinas/farmacocinética , Rivastigmina
5.
Cell Mol Biol (Noisy-le-grand) ; 68(9): 129-134, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36905263

RESUMO

Begomovirus is the largest genus in the family Geminiviridae and constitutes more than 445 virus species. Begomoviruses are characterized by single-stranded circular genomes with monopartite or bipartite components and transmitted by whitefly (Bemisia tabaci). Begomoviruses cause severe diseases in many economically important crops throughout the world. Typical symptoms of a begomovirus infection including severe leaf curling, vein thickening, vein darkening and reduced leaf size were observed in papaya plants in the Dammam district of the Eastern Province of Saudi Arabia during the growing season in 2022. A total of 10 samples were collected, and total genomic DNA was isolated from naturally infected papaya tree samples and subjected to PCR amplification using universal diagnostic primers for begomoviruses and associated satellites. Three PCR-amplified genomic components of begomoviruses and betasatellite namely P61Begomo (645 bp), P62Begomo (341 bp) and P62Beta (563 bp) were sent for Sanger DNA sequencing to Macrogen Inc. These partial viral genome sequences were submitted to Genbank database and accession numbers ON206051, ON206052 and ON206050 were assigned to P61Begomo, P62Begomo and P62Beta respectively. Phylogenetic analysis and pairwise nucleotide sequence identity studies identified P61Begomo was identified as Tomato yellow leaf curl virus, P62Begomo as DNA A component of a bipartite begomovirus Watermelon chlorotic stunt virus and P62Beta as begomovirus associated betasatellite; Cotton leaf curl Gezira betasatellite. To the best of our knowledge, this is the first report of a begomovirus complex infecting papaya (Carica papaya) in the Kingdom of Saudi Arabia.


Assuntos
Begomovirus , Carica , Carica/genética , Begomovirus/genética , Arábia Saudita , Filogenia , Doenças das Plantas , DNA
6.
Appl Opt ; 61(21): 6110-6118, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256222

RESUMO

The D-shaped optical fiber is a base for the magnetite-based graphene nanocomposite (rGO/Fe3O4) for a Pb heavy metal sensing layer. The designed sensor was studied under the effects of rapid annealing, water circulation, and plasmonic tuning. Various annealing temperatures (100°C, 200°C, 300°C, and 400°C) were investigated. The effect of rapid thermal annealing (RTA) temperature on the transmission results were found at a short wavelength of 300 nm and a minimum point of ∼380nm. The bandgap energy was verified between 2.3 and 3.17 eV for 100°C and 400°C, respectively. The sensor results show modification toward a short wavelength by increasing the rapid annealing temperature. Compared with furnace methods, the transmittance shift of the plasmonic effect showed the best performance under the influence of RTA. RTA at 300°C and 400°C offered an acceptable degree of stability at the beginning (1-50 min). The best performance of the proposed sensor was improved by introducing a circulating liquid chamber into the initial design. The resonance shifts due to Pb ion concentration (5, 10, and 15 ppm) were studied for transmission and wavelength shifts. The sensor shift was enhanced by using a free space polarizer controller attached to the second design. The results give detection and sensing potential in the visible range at a possible remarkable response time. The figure of merit was 62.5 a.u., and the maximum sensitivity was 1 a.u./ppm by using a polarizer controller. This article presents the optical characterizations of plasmonic sensor-based rGO/Fe3O4 for detecting Pb ions and enhancing the resonance shift. RTA for composite material and water circulation associated with D-shaped optical fiber enhances response time and stability designed using a polarizer controller.

7.
Am J Med Genet A ; 185(8): 2455-2463, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33963797

RESUMO

Pycnodysostosis is characterized by short stature, osteosclerosis, acro-osteolysis, increased tendency of fractures, and distinctive dysmorphic features. It is a rare autosomal recessive disease caused by biallelic CTSK mutations. The clinical details of 18 patients from Saudi Arabia were reviewed. Short stature, osteopetrosis, acro-osteolysis, and distinctive facial dysmorphism were documented in all cases. Our results highlight the significant complications associated with this disease. The large anterior fontanelle is one of the cardinal signs of this disease; however, half of our patients had small fontanelles and a quarter had craniosynostosis, which caused optic nerve compression. Sleep apnea was of the major complications in three patients. Bone fracture can be a presenting symptom, and in our patients it mainly occurred after the age of 3 years. Bone marrow suppression was seen in a single patient of our cohort who was misdiagnosed initially with malignant osteopetrosis. In this study, we also describe two novel (c.5G > A [p.Trp2Ter], c.538G > A [p.Gly180Ser]) and two reported (c.244-29 A > G, c.830C > T [p.Ala277Val]) CTSK mutations. Our results indicate that the recurrent intronic variant, c.244-29 A > G is likely to be a founder mutation, as it was found in 78% (14/18 patients) of our cohort belonging to the same tribe.


Assuntos
Alelos , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Fenótipo , Picnodisostose/diagnóstico , Picnodisostose/genética , Catepsina K/genética , Pré-Escolar , Consanguinidade , Fácies , Feminino , Estudos de Associação Genética/métodos , Genótipo , Humanos , Imageamento Tridimensional , Masculino , Mutação , Linhagem , Radiografia , Arábia Saudita , Tomografia Computadorizada por Raios X
8.
Anesth Analg ; 132(3): 726-734, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33122543

RESUMO

BACKGROUND: Optimal analgesic treatment following cardiac surgery is crucial for both patient comfort and successful postoperative recovery. While knowledge of both the pharmacokinetics and pharmacodynamics of analgesics is required to predict optimal drug dosing, models quantifying the pharmacodynamics are scarce. Here, we quantify the pharmacodynamics of morphine by modeling the need for rescue morphine to treat unacceptable pain in 118 patients after cardiac surgery. METHODS: The rescue morphine event data were analyzed with repeated time-to-event (RTTE) modeling using NONMEM. Postoperative pain titration protocol consisted of continuous morphine infusions (median duration 20.5 hours) with paracetamol 4 times daily and rescue morphine in case of unacceptable pain (numerical rating scale ≥4). RESULTS: Patients had a median age of 73 years (interquartile range [IQR]: 63-77) and median bodyweight of 80 kg (IQR: 72-90 kg). Most patients (55%) required at least 1 rescue morphine dose. The hazard for rescue morphine following cardiac surgery was found to be significantly influenced by time after surgery, a day/night cycle with a peak at 23:00 (95% confidence interval [CI], 19:35-02:03) each day, and an effect of morphine concentration with 50% hazard reduction at 9.3 ng·mL-1 (95% CI, 6.7-16). CONCLUSIONS: The pharmacodynamics of morphine after cardiac surgery was successfully quantified using RTTE modeling. Future studies can be used to expand the model to better predict morphine's pharmacodynamics on the individual level and to include the pharmacodynamics of other analgesics so that improved postoperative pain treatment protocols can be developed.


Assuntos
Analgésicos Opioides/farmacocinética , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Modelos Teóricos , Morfina/farmacocinética , Manejo da Dor , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Idoso , Analgésicos Opioides/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morfina/administração & dosagem , Dor Pós-Operatória/diagnóstico , Medição de Risco , Fatores de Risco , Resultado do Tratamento
9.
J Pharmacokinet Pharmacodyn ; 48(5): 725-741, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34142308

RESUMO

Predicting brain pharmacokinetics is critical for central nervous system (CNS) drug development yet difficult due to ethical restrictions of human brain sampling. CNS pharmacokinetic (PK) profiles are often altered in CNS diseases due to disease-specific pathophysiology. We previously published a comprehensive CNS physiologically-based PK (PBPK) model that predicted the PK profiles of small drugs at brain and cerebrospinal fluid compartments. Here, we improved this model with brain non-specific binding and pH effect on drug ionization and passive transport. We refer to this improved model as Leiden CNS PBPK predictor V3.0 (LeiCNS-PK3.0). LeiCNS-PK3.0 predicted the unbound drug concentrations of brain ECF and CSF compartments in rats and humans with less than two-fold error. We then applied LeiCNS-PK3.0 to study the effect of altered cerebrospinal fluid (CSF) dynamics, CSF volume and flow, on brain extracellular fluid (ECF) pharmacokinetics. The effect of altered CSF dynamics was simulated using LeiCNS-PK3.0 for six drugs and the resulting drug exposure at brain ECF and lumbar CSF were compared. Simulation results showed that altered CSF dynamics changed the CSF PK profiles, but not the brain ECF profiles, irrespective of the drug's physicochemical properties. Our analysis supports the notion that lumbar CSF drug concentration is not an accurate surrogate of brain ECF, particularly in CNS diseases. Systems approaches account for multiple levels of CNS complexity and are better suited to predict brain PK.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Líquido Cefalorraquidiano/metabolismo , Líquido Extracelular/metabolismo , Animais , Transporte Biológico/fisiologia , Humanos , Modelos Biológicos , Ratos
10.
Plant Dis ; 105(9): 2410-2417, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33599515

RESUMO

Begomoviruses infect food, fiber, and vegetable crop plants, including tomato, potato, bean, cotton, cucumber, and pumpkin, and damage many economically important crop plants worldwide. Tomato leaf curl Sudan virus (ToLCSDV) is the most widespread tomato-infecting begomovirus in Saudi Arabia. Using phage display technology, this study isolated two camel-derived nanobodies against purified ToLCSDV virions from a library of antigen-binding fragments (VHH or nanobody) of heavy-chain antibodies built from an immunized camel. The isolated nanobodies also cross-reacted with purified tomato yellow leaf curl virus virions and showed significant enzyme-linked immunosorbent assay reactivity with extracts from plants with typical begomovirus infection symptoms. The results can pave the way to developing diagnostics for begomovirus detection, design, and characterization of novel nanomaterials based on virus-like particles, in addition to nanobody-mediated begomovirus resistance in economically important crops, such as tomato, potato, and cucumber.


Assuntos
Begomovirus , Anticorpos de Domínio Único , Solanum lycopersicum , Begomovirus/genética , Filogenia , Doenças das Plantas , Anticorpos de Domínio Único/genética
11.
Am J Hum Genet ; 100(1): 117-127, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28017373

RESUMO

From a GeneMatcher-enabled international collaboration, we identified ten individuals affected by intellectual disability, speech delay, ataxia, and facial dysmorphism and carrying a deleterious EBF3 variant detected by whole-exome sequencing. One 9-bp duplication and one splice-site, five missense, and two nonsense variants in EBF3 were found; the mutations occurred de novo in eight individuals, and the missense variant c.625C>T (p.Arg209Trp) was inherited by two affected siblings from their healthy mother, who is mosaic. EBF3 belongs to the early B cell factor family (also known as Olf, COE, or O/E) and is a transcription factor involved in neuronal differentiation and maturation. Structural assessment predicted that the five amino acid substitutions have damaging effects on DNA binding of EBF3. Transient expression of EBF3 mutant proteins in HEK293T cells revealed mislocalization of all but one mutant in the cytoplasm, as well as nuclear localization. By transactivation assays, all EBF3 mutants showed significantly reduced or no ability to activate transcription of the reporter gene CDKN1A, and in situ subcellular fractionation experiments demonstrated that EBF3 mutant proteins were less tightly associated with chromatin. Finally, in RNA-seq and ChIP-seq experiments, EBF3 acted as a transcriptional regulator, and mutant EBF3 had reduced genome-wide DNA binding and gene-regulatory activity. Our findings demonstrate that variants disrupting EBF3-mediated transcriptional regulation cause intellectual disability and developmental delay and are present in ∼0.1% of individuals with unexplained neurodevelopmental disorders.


Assuntos
Ataxia/genética , Face/anormalidades , Deficiência Intelectual/genética , Transtornos do Desenvolvimento da Linguagem/genética , Mutação , Transtornos do Neurodesenvolvimento/genética , Fatores de Transcrição/genética , Transcrição Gênica/genética , Adolescente , Adulto , Substituição de Aminoácidos , Criança , Pré-Escolar , Cromatina/genética , Cromatina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Deficiências do Desenvolvimento/genética , Exoma/genética , Feminino , Regulação da Expressão Gênica/genética , Genes Reporter , Células HEK293 , Humanos , Masculino , Modelos Moleculares , Mosaicismo , Transporte Proteico/genética , Síndrome , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
12.
Am J Hum Genet ; 98(3): 562-570, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26942288

RESUMO

The paradigm of a single gene associated with one specific phenotype and mode of inheritance has been repeatedly challenged. Genotype-phenotype correlations can often be traced to different mutation types, localization of the variants in distinct protein domains, or the trigger of or escape from nonsense-mediated decay. Using whole-exome sequencing, we identified homozygous variants in EMC1 that segregated with a phenotype of developmental delay, hypotonia, scoliosis, and cerebellar atrophy in three families. In addition, a de novo heterozygous EMC1 variant was seen in an individual with a similar clinical and MRI imaging phenotype. EMC1 encodes a member of the endoplasmic reticulum (ER)-membrane protein complex (EMC), an evolutionarily conserved complex that has been proposed to have multiple roles in ER-associated degradation, ER-mitochondria tethering, and proper assembly of multi-pass transmembrane proteins. Perturbations of protein folding and organelle crosstalk have been implicated in neurodegenerative processes including cerebellar atrophy. We propose EMC1 as a gene in which either biallelic or monoallelic variants might lead to a syndrome including intellectual disability and preferential degeneration of the cerebellum.


Assuntos
Atrofia/genética , Deficiências do Desenvolvimento/genética , Variação Genética , Hipotonia Muscular/genética , Proteínas/genética , Escoliose/genética , Adolescente , Alelos , Sequência de Aminoácidos , Atrofia/diagnóstico , Cerebelo/patologia , Criança , Pré-Escolar , Deficiências do Desenvolvimento/diagnóstico , Degradação Associada com o Retículo Endoplasmático , Feminino , Estudos de Associação Genética , Heterozigoto , Humanos , Imageamento por Ressonância Magnética , Masculino , Proteínas de Membrana , Dados de Sequência Molecular , Hipotonia Muscular/diagnóstico , Mutação , Linhagem , Dobramento de Proteína , Proteínas/metabolismo , Escoliose/diagnóstico
13.
Clin Chem Lab Med ; 57(4): 442-451, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30183665

RESUMO

Appropriate antibiotic treatment for respiratory tract infections (RTIs) necessitates rapid and accurate diagnosis of microbial etiology, which remains challenging despite recent innovations. Several host response-based biomarkers due to infection have been suggested to allow discrimination of bacterial and non-bacterial microbial RTI etiology. This review provides an overview of clinical studies that investigated the diagnostic performance of host-response proteomic biomarkers to identify RTI microbial etiology. Procalcitonin and C-reactive protein have been studied most extensively; whereof procalcitonin has demonstrated the strongest diagnostic performance compared to other biomarkers. Proadrenomedullin, soluble triggering receptor expressed on myeloid cells-1, neopterin and pentraxin-3 need more studies to confirm their diagnostic value. For syndecan-4 and lipocalin-2 currently insufficient evidence exists. Common limitations in several of the studies were the relatively small scale setting, heterogeneous patient population and the absence of statistical power calculation.


Assuntos
Infecções Bacterianas/diagnóstico , Proteína C-Reativa/análise , Pró-Calcitonina/análise , Infecções Respiratórias/diagnóstico , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Biomarcadores/análise , Humanos , Infecções Respiratórias/tratamento farmacológico
14.
Hum Mutat ; 39(4): 461-470, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29282788

RESUMO

Mitochondrial DNA (mtDNA) maintenance defects are a group of diseases caused by deficiency of proteins involved in mtDNA synthesis, mitochondrial nucleotide supply, or mitochondrial dynamics. One of the mtDNA maintenance proteins is MPV17, which is a mitochondrial inner membrane protein involved in importing deoxynucleotides into the mitochondria. In 2006, pathogenic variants in MPV17 were first reported to cause infantile-onset hepatocerebral mtDNA depletion syndrome and Navajo neurohepatopathy. To date, 75 individuals with MPV17-related mtDNA maintenance defect have been reported with 39 different MPV17 pathogenic variants. In this report, we present an additional 25 affected individuals with nine novel MPV17 pathogenic variants. We summarize the clinical features of all 100 affected individuals and review the total 48 MPV17 pathogenic variants. The vast majority of affected individuals presented with an early-onset encephalohepatopathic disease characterized by hepatic and neurological manifestations, failure to thrive, lactic acidemia, and mtDNA depletion detected mainly in liver tissue. Rarely, MPV17 deficiency can cause a late-onset neuromyopathic disease characterized by myopathy and peripheral neuropathy with no or minimal liver involvement. Approximately half of the MPV17 pathogenic variants are missense. A genotype with biallelic missense variants, in particular homozygous p.R50Q, p.P98L, and p.R41Q, can carry a relatively better prognosis.


Assuntos
DNA Mitocondrial/genética , Transtornos Heredodegenerativos do Sistema Nervoso , Hepatopatias , Proteínas de Membrana/genética , Doenças Mitocondriais , Proteínas Mitocondriais/genética , Doenças do Sistema Nervoso Periférico , Transtornos Heredodegenerativos do Sistema Nervoso/diagnóstico , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Transtornos Heredodegenerativos do Sistema Nervoso/metabolismo , Humanos , Fígado/metabolismo , Hepatopatias/diagnóstico , Hepatopatias/genética , Hepatopatias/metabolismo , Mitocôndrias/genética , Doenças Mitocondriais/diagnóstico , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Mutação , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/metabolismo
15.
Mol Genet Metab ; 125(3): 281-291, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30177229

RESUMO

An increasing number of mitochondrial diseases are found to be caused by pathogenic variants in nuclear encoded mitochondrial aminoacyl-tRNA synthetases. FARS2 encodes mitochondrial phenylalanyl-tRNA synthetase (mtPheRS) which transfers phenylalanine to its cognate tRNA in mitochondria. Since the first case was reported in 2012, a total of 21 subjects with FARS2 deficiency have been reported to date with a spectrum of disease severity that falls between two phenotypes; early onset epileptic encephalopathy and a less severe phenotype characterized by spastic paraplegia. In this report, we present an additional 15 individuals from 12 families who are mostly Arabs homozygous for the pathogenic variant Y144C, which is associated with the more severe early onset phenotype. The total number of unique pathogenic FARS2 variants known to date is 21 including three different partial gene deletions reported in four individuals. Except for the large deletions, all variants but two (one in-frame deletion of one amino acid and one splice-site variant) are missense. All large deletions and the single splice-site variant are in trans with a missense variant. This suggests that complete loss of function may be incompatible with life. In this report, we also review structural, functional, and evolutionary significance of select FARS2 pathogenic variants reported here.


Assuntos
Aminoacil-tRNA Sintetases/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Fenilalanina-tRNA Ligase/genética , Adolescente , Adulto , Aminoacil-tRNA Sintetases/deficiência , Criança , Pré-Escolar , Feminino , Deleção de Genes , Humanos , Masculino , Mitocôndrias/enzimologia , Mitocôndrias/patologia , Doenças Mitocondriais/enzimologia , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/química , Proteínas Mitocondriais/deficiência , Mutação/genética , Paraplegia/genética , Paraplegia/patologia , Fenilalanina/genética , Fenilalanina/metabolismo , Fenilalanina-tRNA Ligase/química , Fenilalanina-tRNA Ligase/deficiência , Isoformas de Proteínas/genética , Relação Estrutura-Atividade , Adulto Jovem
16.
Hum Mutat ; 38(12): 1649-1659, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28940506

RESUMO

F-box and leucine-rich repeat protein 4 (FBXL4) is a mitochondrial protein whose exact function is not yet known. However, cellular studies have suggested that it plays significant roles in mitochondrial bioenergetics, mitochondrial DNA (mtDNA) maintenance, and mitochondrial dynamics. Biallelic pathogenic variants in FBXL4 are associated with an encephalopathic mtDNA maintenance defect syndrome that is a multisystem disease characterized by lactic acidemia, developmental delay, and hypotonia. Other features are feeding difficulties, growth failure, microcephaly, hyperammonemia, seizures, hypertrophic cardiomyopathy, elevated liver transaminases, recurrent infections, variable distinctive facial features, white matter abnormalities and cerebral atrophy found in neuroimaging, combined deficiencies of multiple electron transport complexes, and mtDNA depletion. Since its initial description in 2013, 36 different pathogenic variants in FBXL4 were reported in 50 affected individuals. In this report, we present 37 additional affected individuals and 11 previously unreported pathogenic variants. We summarize the clinical features of all 87 individuals with FBXL4-related mtDNA maintenance defect, review FBXL4 structure and function, map the 47 pathogenic variants onto the gene structure to assess the variants distribution, and investigate the genotype-phenotype correlation. Finally, we provide future directions to understand the disease mechanism and identify treatment strategies.


Assuntos
DNA Mitocondrial/genética , Proteínas F-Box/genética , Estudos de Associação Genética , Encefalomiopatias Mitocondriais/genética , Ubiquitina-Proteína Ligases/genética , Acidose Láctica/genética , Cardiomiopatia Hipertrófica/genética , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Mitocôndrias/genética , Encefalomiopatias Mitocondriais/epidemiologia , Encefalomiopatias Mitocondriais/patologia , Proteínas Mitocondriais/genética , Hipotonia Muscular/genética , Mutação , Fosforilação Oxidativa , Proteoma/genética
17.
J Oral Maxillofac Surg ; 75(6): 1124-1135, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28236425

RESUMO

PURPOSE: To assess the effect of platelet-rich fibrin (PRF) on the healing process of the alveolar socket after surgical extraction of the mandibular third molars. MATERIALS AND METHODS: PubMed, the Cochrane Central Register of Controlled Trials, Scopus, and relevant journals were searched using a combination of specific keywords ("platelet-rich fibrin," "oral surgery," and "third molar"). The final search was conducted on November 2, 2015. Randomized controlled clinical trials, as well as controlled clinical trials, aimed at comparing the effect of PRF versus natural healing after extraction of mandibular third molars were included. RESULTS: Five randomized controlled trials and one controlled clinical trial were included. There were 335 extractions (168 with PRF and 167 controls) in 183 participants. Considerable heterogeneity in study characteristics, outcome variables, and estimated scales was observed. Positive results were generally recorded for pain, trismus, swelling, periodontal pocket depth, soft tissue healing, and incidence of localized osteitis, but not in all studies. However, no meta-analysis could be conducted for such variables because of the different measurement scales used. The qualitative and meta-analysis results showed no significant improvement in bone healing with PRF-treated sockets compared with the naturally healing sockets. CONCLUSIONS: Within the limitations of the available evidence, PRF seems to have no beneficial role in bone healing after extraction of the mandibular third molars. Future standardized randomized controlled clinical trials are required to estimate the effect of PRF on socket regeneration.


Assuntos
Plaquetas/fisiologia , Fibrina/uso terapêutico , Dente Serotino/cirurgia , Extração Dentária , Alvéolo Dental/fisiologia , Dente Impactado/cirurgia , Cicatrização/fisiologia , Humanos , Mandíbula/cirurgia
18.
Plant Dis ; 101(5): 761-765, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-30678580

RESUMO

Applications of formulated bacteriophages with skim milk and sucrose or nonformulated bacteriophages combined with acibenzolar-S-methyl (ASM) were compared with copper bactericides applications for suppressing Asiatic citrus canker (ACC) caused by Xanthomonas citri subsp. citri (Xcc) on leaves under greenhouse and field conditions in Saudi Arabia. Bacteriophages were applied one day prior to inoculation of Mexican lime (Citrus aurantifolia) plants with Xcc, then twice a week until the end of the trials. Copper hydroxide was applied once prior to inoculation and then every seven days afterward, whereas ASM was applied one week prior to inoculation and then every 21 days afterward. Under greenhouse conditions, the incidence of ACC on leaves was reduced significantly from 75.2 to 12.8% or 18.3% for plants treated with copper hydroxide or bacteriophages in combination with ASM, respectively. Applications of formulated phages in combination with ASM as soil drench under field conditions significantly decreased disease incidence by 14.8% (Trial 1) and 16.8% (Trial 2) compared with untreated control plants. Overall, the Xcc-inoculated plants treated with bacteriophages + ASM combination showed significant ACC reduction under greenhouse and field conditions. The bacteriophages + ASM combination tested in these trials can be an effective tool in the integrated management programs of Asiatic citrus canker disease.

19.
Am J Med Genet A ; 170A(5): 1142-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26842963

RESUMO

ADAT3-related intellectual disability has been recently described in 24 individuals from eight Saudi families who had cognitive impairment and strabismus. Other common features included growth failure, microcephaly, tone abnormalities, epilepsy, and nonspecific brain abnormalities. A single homozygous founder mutation (c.382G>A:p.(V128M)) in the ADAT3 gene, which encodes a protein that functions in tRNA editing, was identified in all affected individuals. In this report, we present additional 15 individuals from 11 families (10 Saudis and 1 Emirati) who are homozygous for the same founder mutation. In addition to the universal findings of intellectual disability and strabismus, the majority exhibited microcephaly and growth failure. Additional features not reported in the original cohort include dysmorphic facial features (prominent forehead, up-slanted palpebral fissures, epicanthus, and depressed nasal bridge), behavioral problems (hyperactivity and aggressiveness), recurrent otitis media, and growth hormone deficiency. ADAT3-related intellectual disability is an important recognizable cause of intellectual disability in Arabia.


Assuntos
Adenosina Desaminase/genética , Disfunção Cognitiva/genética , Deficiência Intelectual/genética , Estrabismo/genética , Adolescente , Adulto , Criança , Pré-Escolar , Disfunção Cognitiva/complicações , Disfunção Cognitiva/fisiopatologia , Feminino , Efeito Fundador , Hormônio do Crescimento/genética , Humanos , Lactente , Deficiência Intelectual/complicações , Deficiência Intelectual/fisiopatologia , Masculino , Fenótipo , Estrabismo/complicações , Estrabismo/fisiopatologia
20.
Am J Orthod Dentofacial Orthop ; 150(4): 703-712, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27692428

RESUMO

INTRODUCTION: Our objectives were to assess reliability, validity, and time efficiency of semiautomatic segmentation using Segura software of the nasal and pharyngeal airways, against manual segmentation with point-based analysis with color mapping. METHODS: Pharyngeal and nasal airways from 10 cone-beam computed tomography image sets were segmented manually and semiautomatically using Segura (University of Alberta, Edmonton, Alberta, Canada). To test intraexaminer and interexaminer reliabilities, semiautomatic segmentation was repeated 3 times by 1 examiner and then by 3 examiners. In addition to volume and surface area, point-based analysis was completed to assess the reconstructed 3-dimensional models from Segura against manual segmentation. The times of both methods of segmentation were also recorded to assess time efficiency. RESULTS: The reliability and validity of Segura were excellent (intraclass correlation coefficient, >0.9 for volume and surface area). Part analysis showed small differences between the Segura and manually segmented 3-dimensional models (greatest difference did not exceed 4.3 mm). Time of segmentation using Segura was significantly shorter than that for manual segmentation, 49 ± 11.0 vs 109 ± 9.4 minutes (P <0.001). CONCLUSIONS: Semiautomatic segmentation of the pharyngeal and nasal airways using Segura was found to be reliable, valid, and time efficient. Part analysis with color mapping was the key to explaining differences in upper airway volume and provides meaningful and clinically relevant analysis of 3-dimensional changes.


Assuntos
Algoritmos , Tomografia Computadorizada de Feixe Cônico , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Cavidade Nasal/diagnóstico por imagem , Faringe/diagnóstico por imagem , Ventilação Pulmonar/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos
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