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1.
J Infect Dis ; 229(1): 262-272, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-37855446

RESUMEN

Periodontitis is an exemplar of dysbiosis associated with the coordinated action of multiple members within the microbial consortium. The polymicrobial synergy and dysbiosis hypothesis proposes a dynamic host-microbiome balance, with certain modulators capable of disrupting eubiosis and driving shifts towards dysbiosis within the community. However, these factors remain to be explored. We established a Porphyromonas gingivalis- or Aggregatibacter actinomycetemcomitans-modified subgingival microbiome model and 16S rRNA sequencing revealed that P. gingivalis and A. actinomycetemcomitans altered the microbiome structure and composition indicated by α and ß diversity metrics. P. gingivalis increased the subgingival dysbiosis index (SDI), while A. actinomycetemcomitans resulted in a lower SDI. Furthermore, P. gingivalis-stimulated microbiomes compromised epithelium function and reduced expression of tight junction proteins, whereas A. actinomycetemcomitans yielded mild effects. In conclusion, by inoculating P. gingivalis, we created dysbiotic microcosm biofilms in vitro resembling periodontitis-related subgingival microbiota, exhibiting enhanced dysbiosis and impaired epithelium integrity.


Asunto(s)
Microbiota , Periodontitis , Humanos , Porphyromonas gingivalis , Aggregatibacter actinomycetemcomitans/genética , ARN Ribosómico 16S/genética , Disbiosis
2.
Can J Neurol Sci ; : 1-12, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38178730

RESUMEN

OBJECTIVES: Spinal muscular atrophy (SMA) is a leading genetic cause of infant death and represents a significant burden of care. An improved understanding of the epidemiology of SMA in Canada may help inform strategies to improve the standard of care for individuals living with SMA. METHODS: We employed a multisource approach to estimate the minimal incidence and prevalence of 5q SMA and to gain greater insight into recent clinical practices and treatment trends for the Canadian SMA population. Data sources included the Canadian Paediatric Surveillance Program (CPSP), Canadian Neuromuscular Disease Registry (CNDR), and molecular genetics laboratories in Canada. RESULTS: The estimated annual minimum incidence of 5q SMA was 4.38, 3.44, and 7.99 cases per 100,000 live births in 2020 and 2021, based on CPSP, CNDR, and molecular genetics laboratories data, respectively, representing approximately 1 in 21,472 births (range 12,516-29,070) in Canada. SMA prevalence was estimated to be 0.85 per 100,000 persons aged 0-79 years. Delay in diagnosis exists across all SMA subtypes. Most common presenting symptoms were delayed milestones, hypotonia, and muscle weakness. Nusinersen was the most common disease-modifying treatment received. Most patients utilized multidisciplinary clinics for management of SMA. CONCLUSION: This study provides data on the annual minimum incidence of pediatric 5q SMA in Canada. Recent therapeutic advances and newborn screening have the potential to drastically alter the natural history of SMA. Findings underline the importance of ongoing surveillance of the epidemiology and long-term health outcomes of SMA in the Canadian population.

3.
Clin Genet ; 103(3): 288-300, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36353900

RESUMEN

We examined the utility of clinical and research processes in the reanalysis of publicly-funded clinical exome sequencing data in Ontario, Canada. In partnership with eight sites, we recruited 287 families with suspected rare genetic diseases tested between 2014 and 2020. Data from seven laboratories was reanalyzed with the referring clinicians. Reanalysis of clinically relevant genes identified diagnoses in 4% (13/287); four were missed by clinical testing. Translational research methods, including analysis of novel candidate genes, identified candidates in 21% (61/287). Of these, 24 families have additional evidence through data sharing to support likely diagnoses (8% of cohort). This study indicates few diagnoses are missed by clinical laboratories, the incremental gain from reanalysis of clinically-relevant genes is modest, and the highest yield comes from validation of novel disease-gene associations. Future implementation of translational research methods, including continued reporting of compelling genes of uncertain significance by clinical laboratories, should be considered to maximize diagnoses.


Asunto(s)
Pruebas Genéticas , Humanos , Pruebas Genéticas/métodos , Ontario/epidemiología , Secuenciación del Exoma
4.
Am J Med Genet A ; 191(2): 338-347, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36331261

RESUMEN

The introduction of clinical exome sequencing (ES) has provided a unique opportunity to decrease the diagnostic odyssey for patients living with a rare genetic disease (RGD). ES has been shown to provide a diagnosis in 29%-57% of patients with a suspected RGD, with as many as 70% remaining undiagnosed. There is a need to advance the clinical model of care by more formally integrating approaches that were previously considered research into an enhanced diagnostic workflow. We developed an Exome Clinic, which set out to evaluate a workflow for improving the diagnostic yield of ES for patients with an undiagnosed RGD. Here, we report the outcomes of 47 families who underwent clinical ES in the first year of the clinic. The diagnostic yield from clinical ES was 40% (19/47). Families who remained undiagnosed after ES had the opportunity for follow-up studies that included phenotyping and candidate variant segregation in relatives, genomic matchmaking, and ES reanalysis. This enhanced diagnostic workflow increased the diagnostic yield to 55% (26/47), predominantly through the resolution of variants and genes of uncertain significance. We advocate that this approach be integrated into mainstream clinical practice and highlight the importance of a coordinated translational approach for patients with RGD.


Asunto(s)
Genómica , Enfermedades Raras , Humanos , Secuenciación del Exoma , Canadá , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Oligopéptidos/genética , Pruebas Genéticas
5.
Int J Mol Sci ; 24(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36982143

RESUMEN

A large amount of cyanide-containing wastewater is discharged during electrode material synthesis. Among them, cyanides will form metal-cyanide complex ions which possess high stability, making it challenging to separate them from these wastewaters. Therefore, it is imperative to understand the complexation mechanism of cyanide ions and heavy metal ions from wastewater in order to obtain a deep insight into the process of cyanide removal. This study employs Density Functional Theory (DFT) calculations to reveal the complexation mechanism of metal-cyanide complex ions formed by the interaction of Cu+ and CN- in copper cyanide systems and its transformation patterns. Quantum chemical calculations show that the precipitation properties of Cu(CN)43- can assist in the removal of CN-. Therefore, transferring other metal-cyanide complex ions to Cu(CN)43- can achieve deep removal. OLI studio 11.0 analyzed the optimal process parameters of Cu(CN)43- under different conditions and determined the optimal process parameters of the removal depth of CN-. This work has the potential to contribute to the future preparation of related materials such as CN- removal adsorbents and catalysts and provide theoretical foundations for the development of more efficient, stable, and environmentally friendly next-generation energy storage electrode materials.


Asunto(s)
Complejos de Coordinación , Contaminantes Químicos del Agua , Aguas Residuales , Cobre/química , Cianuros/química , Agua , Especificidad de la Especie , Iones , Contaminantes Químicos del Agua/química
6.
Molecules ; 28(9)2023 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-37175356

RESUMEN

Oral health is crucial to daily life, yet many people worldwide suffer from oral diseases. With the development of oral tissue engineering, there is a growing demand for dental biomaterials. Addressing oral diseases often requires a two-fold approach: fighting bacterial infections and promoting tissue growth. Hydrogels are promising tissue engineering biomaterials that show great potential for oral tissue regeneration and drug delivery. In this review, we present a classification of hydrogels commonly used in dental research, including natural and synthetic hydrogels. Furthermore, recent applications of these hydrogels in endodontic restorations, periodontal tissues, mandibular and oral soft tissue restorations, and related clinical studies are also discussed, including various antimicrobial and tissue growth promotion strategies used in the dental applications of hydrogels. While hydrogels have been increasingly studied in oral tissue engineering, there are still some challenges that need to be addressed for satisfactory clinical outcomes. This paper summarizes the current issues in the abovementioned application areas and discusses possible future developments.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Humanos , Materiales Biocompatibles/farmacología , Hidrogeles/farmacología , Periodoncio
7.
Hum Mol Genet ; 28(6): 952-960, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30476144

RESUMEN

THOC6 encodes a subunit of the THO complex that is part of a highly conserved transcription and export complex known to have roles in mRNA processing and export. Few homozygous or compound heterozygous variants have been identified in the THOC6 gene in patients with a syndromic form of intellectual disability [Beaulieu-Boycott-Innes syndrome (BBIS); MIM: 613680]. Here we report two additional individuals affected with BBIS originating from the north of Europe and sharing a haplotype composed of three very rare missense changes in the THOC6 gene-Trp100Arg, Val234Leu, Gly275Asp. The first individual is a boy who is homozygous for the three-variant haplotype due to a maternal uniparental disomy event. The second is a girl who is compound heterozygous for this haplotype and a previously reported Gly190Glu missense variant. We analyzed the impact of these different amino acid changes on THOC6 protein expression, cellular localization and interaction with the other THO complex subunits. We show that the different THOC6 variants alter the physiological nuclear localizationof the protein and its interaction with at least two THO subunits, THOC1 and THOC5. Two amino acid changes from the three-variant haplotype alone have specific effects and might contribute to the pathogenicity of the haplotype. Overall, we expanded the cohort of currently known individuals with BBIS by reporting two individuals carrying the same recurrent European haplotype composed of three amino acid changes, affecting THOC6 localization and interaction with THO protein partners.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Mutación Missense , Fenotipo , Proteínas de Unión al ARN/genética , Alelos , Línea Celular , Preescolar , Europa (Continente) , Femenino , Expresión Génica , Estudios de Asociación Genética/métodos , Genotipo , Haplotipos , Humanos , Masculino , Modelos Biológicos , Linaje , Conformación Proteica , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/metabolismo , Relación Estructura-Actividad
8.
Hum Genet ; 140(2): 289-297, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32627054

RESUMEN

Whole exome sequencing (WES)-based assays undergo rigorous validation before being implemented in diagnostic laboratories. This validation process generates experimental evidence that allows laboratories to predict the performance of the intended assay. The NA12878 Genome in a Bottle (GIAB) HapMap reference sample is commonly used for validation in diagnostic laboratories. We investigated what data points should be taken into consideration when validating WES-based assays using the GIAB reference in a diagnostic setting. We delineate specific factors that require special consideration and identify OMIM genes associated with diseases that may 'bypass' validation. Four replicates of the NA12878 sample were sequenced at the CHEO Genetics Diagnostic Laboratory on a NextSeq 500; the data were analyzed using the bcbio_nexgen v1.1.2 pipeline. The hap.py validation engine, Real Time Genomics vcfeval tool, and high confidence (HC) variant calls in HC regions available for the GIAB sample were used to validate the obtained variant calls. The same validation process was then used to evaluate variant calls obtained for the same sample by two other clinical diagnostic laboratories. We showed that variant calls in NA12878 can be confidently measured only in the regions that intersect between the GIAB HC regions and the target regions of exome capture. Of the 4139 (as of October 2019) OMIM genes associated with a phenotype and having a known molecular basis of disease, 84 were fully outside of the GIAB HC regions and many of the remaining OMIM genes were only partially covered by the HC regions. A significant proportion of variants identified in the NA12878 sample outside of the HC regions have unknown (UNK) status due to the absence of HC reference alleles. Verification of such calls is possible either by an alternative truth set or by orthogonal testing. Similarly, many variants outside of exome capture regions, if not accounted for, will be deemed false negatives due to insufficient probe coverage. Our results demonstrate the importance of the intersection between genomic regions of interest, capture regions, and the high confidence regions. If not considered, false and ambiguous variant calls could have a negative impact on diagnostic accuracy of the intended WES-based diagnostic assay and increase the need for confirmatory testing. To enable laboratories to identify 'problematic' regions and optimize validation efforts, we have made our VCF and BED files available in UCSC Genome Browser: NA12878 WES Benchmark. Relevant genes and genome annotations are evolving, we implemented a general purpose algorithm to cross-reference OMIM genes with the genomic regions of interest that can be applied to capture genes/regions outside HC regions (see repository of data material section).


Asunto(s)
Secuenciación del Exoma/métodos , Genoma Humano/genética , Alelos , Exoma/genética , Variación Genética/genética , Genómica/métodos , Humanos , Anotación de Secuencia Molecular/métodos
9.
Am J Hum Genet ; 103(5): 727-739, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30388400

RESUMEN

Primary defects in motile cilia result in dysfunction of the apparatus responsible for generating fluid flows. Defects in these mechanisms underlie disorders characterized by poor mucus clearance, resulting in susceptibility to chronic recurrent respiratory infections, often associated with infertility; laterality defects occur in about 50% of such individuals. Here we report biallelic variants in LRRC56 (known as oda8 in Chlamydomonas) identified in three unrelated families. The phenotype comprises laterality defects and chronic pulmonary infections. High-speed video microscopy of cultured epithelial cells from an affected individual showed severely dyskinetic cilia but no obvious ultra-structural abnormalities on routine transmission electron microscopy (TEM). Further investigation revealed that LRRC56 interacts with the intraflagellar transport (IFT) protein IFT88. The link with IFT was interrogated in Trypanosoma brucei. In this protist, LRRC56 is recruited to the cilium during axoneme construction, where it co-localizes with IFT trains and is required for the addition of dynein arms to the distal end of the flagellum. In T. brucei carrying LRRC56-null mutations, or a variant resulting in the p.Leu259Pro substitution corresponding to the p.Leu140Pro variant seen in one of the affected families, we observed abnormal ciliary beat patterns and an absence of outer dynein arms restricted to the distal portion of the axoneme. Together, our findings confirm that deleterious variants in LRRC56 result in a human disease and suggest that this protein has a likely role in dynein transport during cilia assembly that is evolutionarily important for cilia motility.


Asunto(s)
Transporte Biológico/genética , Flagelos/genética , Depuración Mucociliar/genética , Mutación/genética , Proteínas/genética , Adulto , Alelos , Axonema/genética , Línea Celular , Chlamydomonas/genética , Cilios/genética , Dineínas/genética , Células Epiteliales/patología , Femenino , Células HEK293 , Humanos , Lactante , Masculino , Fenotipo , Trypanosoma brucei brucei/genética
10.
Sensors (Basel) ; 21(13)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202766

RESUMEN

At present, synthetic aperture radar (SAR) automatic target recognition (ATR) has been deeply researched and widely used in military and civilian fields. SAR images are very sensitive to the azimuth aspect of the imaging geomety; the same target at different aspects differs greatly. Thus, the multi-aspect SAR image sequence contains more information for classification and recognition, which requires the reliable and robust multi-aspect target recognition method. Nowadays, SAR target recognition methods are mostly based on deep learning. However, the SAR dataset is usually expensive to obtain, especially for a certain target. It is difficult to obtain enough samples for deep learning model training. This paper proposes a multi-aspect SAR target recognition method based on a prototypical network. Furthermore, methods such as multi-task learning and multi-level feature fusion are also introduced to enhance the recognition accuracy under the case of a small number of training samples. The experiments by using the MSTAR dataset have proven that the recognition accuracy of our method can be close to the accruacy level by all samples and our method can be applied to other feather extraction models to deal with small sample learning problems.


Asunto(s)
Reconocimiento de Normas Patrones Automatizadas , Radar , Algoritmos
11.
Am J Med Genet A ; 182(3): 498-503, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31840929

RESUMEN

Renpenning syndrome (OMIM: 309500) is a rare X-linked disorder that causes intellectual disability, microcephaly, short stature, a variety of eye anomalies, and characteristic craniofacial features. This condition results from pathogenic variation of PQBP1, a polyglutamine-binding protein involved in transcription and pre-mRNA splicing. Renpenning syndrome has only been reported in affected males. Carrier females do not usually have clinical features, and in reported families with Renpenning syndrome, most female carriers exhibit favorable skewing of X-chromosome inactivation. We describe a female with syndromic features typical of Renpenning syndrome. She was identified by exome sequencing to have a de novo heterozygous c.459_462delAGAG mutation in PQBP1 (Xp11.23), affecting the AG hexamer in exon 4, which is the most common causative mutation in this syndrome. Streaky hypopigmentation of the skin was observed, supporting a hypothesized presence of an actively expressed, PQBP1 mutation-bearing X-chromosome in some cells. X-inactivation studies on peripheral blood cells demonstrated complete skewing in both the proband and her mother with preferential inactivation of the maternal X chromosome in the child. We demonstrated expression of the PQBP1 mutant transcript in leukocytes of the affected girl. Therefore, it is highly likely that the PQBP1 mutation arose from the paternal X chromosome.


Asunto(s)
Anomalías Múltiples/genética , Parálisis Cerebral/genética , Proteínas de Unión al ADN/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Discapacidad Intelectual Ligada al Cromosoma X/genética , Anomalías Múltiples/diagnóstico , Anomalías Múltiples/patología , Parálisis Cerebral/diagnóstico , Parálisis Cerebral/patología , Niño , Cromosomas Humanos X/genética , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/diagnóstico , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Humanos , Masculino , Discapacidad Intelectual Ligada al Cromosoma X/diagnóstico , Discapacidad Intelectual Ligada al Cromosoma X/patología , Mutación/genética , Inactivación del Cromosoma X/genética
12.
Hum Mol Genet ; 26(9): 1706-1715, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334793

RESUMEN

There are over 150 known human proteins which are tethered to the cell surface via glycosylphosphatidylinositol (GPI) anchors. These proteins play a variety of important roles in development, and particularly in neurogenesis. Not surprisingly, mutations in the GPI anchor biosynthesis and remodeling pathway cause a number of developmental disorders. This group of conditions has been termed inherited GPI deficiencies (IGDs), a subgroup of congenital disorders of glycosylation; they present with variable phenotypes, often including seizures, hypotonia and intellectual disability. Here, we report two siblings with compound heterozygous variants in the gene phosphatidylinositol glycan anchor biosynthesis, class P (PIGP) (NM_153681.2: c.74T > C;p.Met25Thr and c.456delA;p.Glu153AsnFs*34). PIGP encodes a subunit of the enzyme that catalyzes the first step of GPI anchor biosynthesis. Both children presented with early-onset refractory seizures, hypotonia, and profound global developmental delay, reminiscent of other IGD phenotypes. Functional studies with patient cells showed reduced PIGP mRNA levels, and an associated reduction of GPI-anchored cell surface proteins, which was rescued by exogenous expression of wild-type PIGP. This work associates mutations in the PIGP gene with a novel autosomal recessive IGD, and expands our knowledge of the role of PIG genes in human development.


Asunto(s)
Hexosiltransferasas/genética , Proteínas de la Membrana/genética , Espasmos Infantiles/genética , Anomalías Múltiples/genética , Adulto , Línea Celular , Niño , Discapacidades del Desarrollo/genética , Glicosilfosfatidilinositoles/deficiencia , Glicosilfosfatidilinositoles/genética , Glicosilfosfatidilinositoles/metabolismo , Hemoglobinuria Paroxística/genética , Hexosiltransferasas/metabolismo , Humanos , Discapacidad Intelectual/genética , Proteínas de la Membrana/metabolismo , Hipotonía Muscular/genética , Mutación , Linaje , Convulsiones/genética , Espasmos Infantiles/metabolismo
13.
Sensors (Basel) ; 19(2)2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30669345

RESUMEN

This paper focuses on an improved imaging algorithm for spotlight synthetic aperture radar (SAR) with continuous Pulse Repetition Interval (PRI) variation in extremely high-resolution. Conventional SAR systems are limited in that a wide swath cannot be achieved with a high azimuth resolution in the meantime. This limitation can be overcome by Pulse Repetition Frequency (PRF) variation in a SAR system. However, there are problems such as the ambiguities of point targets or extended targets caused by nonuniform sampling. A reconstructive method, Nonuniform Discrete Fourier Transform (NUDFT) has been presented in the current literature, but it is rather computationally expensive. In this paper, a modified sinc interpolation based on NUDFT is proposed, which is used to reconstruct the uniformly sampled echo in time domain. Since the interpolation kernel length is relatively short, it is more computationally efficient. Then, the two-step processing approach combined with the modified sinc interpolation is further presented, which has much better accuracy than that combined with the conventional sinc interpolation. Both the simulated data and the extracted GF-3 data experiment demonstrate the validity and accuracy of the proposed approach.

14.
Sensors (Basel) ; 19(22)2019 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-31726674

RESUMEN

Circular synthetic aperture radar (CSAR) has a 360° observation capability on the central observation scenario. A typical way to process CSAR imaging is to cut data into small sub-apertures because most targets are only coherent at a very small observation angle. There are many sub-aperture imaging methods after development in recent years. The back-projection algorithm is widely used because it is simple and can be applied to an arbitrary trajectory. Because of the limitation of the Nyquist sampling frequency and influence of the antenna sidelobe, azimuth ambiguity is a phenomenon that may occur in the radar imaging process. The existing researches typically choose the back-projection (BP) imaging area according to the SAR platform flight path and the antenna beam width. The limitation of the CSAR imaging area and its azimuth ambiguity region are rarely analyzed theoretically. This paper focus on the sub-aperture imaging of CSAR, based on the BP algorithm, which derives the relationship of azimuth ambiguity with CSAR parameters such as the pause repeat frequency (PRF), slant range angle, velocity of radar platform, etc. This paper proposes an equation for the calculation of the azimuth ambiguity region and analyzes the limitations, which provides theoretical support for CSAR parameter design, imaging area selection, and azimuth ambiguity analysis.

15.
Biofouling ; 34(8): 870-879, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30326724

RESUMEN

This study investigated how the physiological states of Aggregatibacter actinomycetemcomitans (Aa) and Streptococcus mitis affect their intracellular invasion capabilities and the resulting host cell responses. The physiological states included two forms of planktonic states, floating or sedimented (by centrifugation) and the biofilm state (with centrifugation). Confluent epithelial Ca9-22 cells were challenged with floating or sedimented planktonic cultures, or with 24-h biofilms for 3 h. The results show that intracellular invasion efficiencies were clearly affected by the bacterial physiological states. For both bacterial species, the sedimented-cells displayed 2-10 times higher invasion efficiency than the floating-cells (p < 0.05). The invasion efficiency of Aa biofilms was three fold lower than sedimented cells, whereas those of S. mitis biofilms were similar to sedimented cells. Unlike invasion, the metabolic activities of Ca9-22 were unaffected by different bacterial physiological states. However, Aa biofilms induced higher IL-1ß expression than planktonic cultures. In conclusion, different bacterial physiological states can affect the outcomes of (in vitro) host-microbe interaction in different ways.


Asunto(s)
Aggregatibacter actinomycetemcomitans/fisiología , Biopelículas/crecimiento & desarrollo , Células Epiteliales/microbiología , Interacciones Microbiota-Huesped/fisiología , Plancton/fisiología , Streptococcus mitis/fisiología , Línea Celular , Humanos
16.
Sensors (Basel) ; 18(12)2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30513763

RESUMEN

When the original echo data of SAR are saturated for quantization, the performance of the commonly used block adaptive quantization (BAQ) algorithm will be degraded, which will degrade the imaging quality. This article proposes an improved Llody-Max codec method, which only needs to change the codec look-up table to get better quantization performance when the original echo is saturated. The simulation results show that the proposed method can reduce the quantization power loss, improve the echo signal-to-noise ratio (SNR), and reduce the influence of quantization saturation on the scattering mechanism of polarized SAR data, which have good practical application value.

17.
Sensors (Basel) ; 18(4)2018 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-29565316

RESUMEN

Spotlight synthetic aperture radar (SAR) is a proven technique, which can provide high-resolution images as compared to those produced by traditional stripmap SAR. This paper addresses a high-resolution SAR focusing experiment based on Gaofen-3 satellite (GF-3) staring data with about 55 cm azimuth resolution and 240 MHz range bandwidth. In staring spotlight (ST) mode, the antenna always illuminates the same scene on the ground, which can extend the synthetic aperture. Based on a two-step processing algorithm, some special aspects such as curved-orbit model error correction, stop-and-go correction, and antenna pattern demodulation must be considered in image focusing. We provide detailed descriptions of all these aspects and put forward corresponding solutions. Using these suggested methods directly in an imaging module without any modification for other data processing software can make the most of the existing ground data processor. Finally, actual data acquired in GF-3 ST mode is used to validate these methodologies, and a well-focused, high-resolution image is obtained as a result of this focusing experiment.

18.
Hum Mutat ; 38(5): 511-516, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28185376

RESUMEN

Deleterious variants in the same gene present in two or more families with overlapping clinical features provide convincing evidence of a disease-gene association; this can be a challenge in the study of ultrarare diseases. To facilitate the identification of additional families, several groups have created "matching" platforms. We describe four individuals from three unrelated families "matched" by GeneMatcher and MatchMakerExchange. Individuals had microcephaly, developmental delay, epilepsy, and recessive mutations in TRIT1. A single homozygous mutation in TRIT1 associated with similar features had previously been reported in one family. The identification of these individuals provides additional evidence to support TRIT1 as the disease-causing gene and interprets the variants as "pathogenic." TRIT1 functions to modify mitochondrial tRNAs and is necessary for protein translation. We show that dysfunctional TRIT1 results in decreased levels of select mitochondrial proteins. Our findings confirm the TRIT1 disease association and advance the phenotypic and molecular understanding of this disorder.


Asunto(s)
Transferasas Alquil y Aril/genética , Alelos , Genes Recesivos , Enfermedades Mitocondriales/diagnóstico , Enfermedades Mitocondriales/genética , Mutación , Adolescente , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Niño , Preescolar , Facies , Femenino , Pruebas Genéticas , Homocigoto , Humanos , Imagen por Resonancia Magnética , Masculino , Fenotipo
19.
Am J Med Genet A ; 173(1): 126-134, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27633801

RESUMEN

Aminoacyl-tRNA synthetases (ARSs) are a group of ubiquitously expressed enzymes that are best known for their function in the first step of protein translation but have been increasingly associated with secondary functions including transcription and translation control and extracellular signaling. Mutations in numerous ARSs have been linked to a growing number of both autosomal dominant and autosomal recessive human diseases. The tyrosyl-tRNA synthetase (YARS) links the amino acid tyrosine to its cognate tRNA. We report two siblings who presented with failure to thrive (FTT), hypertriglyceridemia, developmental delay, liver dysfunction, lung cysts, and abnormal subcortical white matter. Using exome sequencing the siblings were found to harbor bi-allelic pathogenic-appearing variants within the YARS gene (NM_003680.3):c.638C>T p.(Pro213Leu) and c.1573G>A p.(Gly525Arg). These YARS variants occur in the catalytic domain and the C-terminal domain, respectively. Mutations in YARS have been previously associated with an autosomal dominant form of Charcot-Marie-Tooth (CMT); our findings suggest the disease spectrum associated with YARS dysregulation is broader than peripheral neuropathy. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Genes Dominantes , Estudios de Asociación Genética , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/genética , Mutación , Fenotipo , Tirosina-ARNt Ligasa/genética , Alelos , Facies , Genotipo , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Modelos Moleculares , Linaje , Conformación Proteica , Análisis de Secuencia de ADN , Hermanos , Tomografía Computarizada por Rayos X , Tirosina-ARNt Ligasa/química
20.
Hum Mutat ; 37(2): 148-54, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26507355

RESUMEN

Mandibulofacial dysostosis with microcephaly (MFDM) is a multiple malformation syndrome comprising microcephaly, craniofacial anomalies, hearing loss, dysmorphic features, and, in some cases, esophageal atresia. Haploinsufficiency of a spliceosomal GTPase, U5-116 kDa/EFTUD2, is responsible. Here, we review the molecular basis of MFDM in the 69 individuals described to date, and report mutations in 38 new individuals, bringing the total number of reported individuals to 107 individuals from 94 kindreds. Pathogenic EFTUD2 variants comprise 76 distinct mutations and seven microdeletions. Among point mutations, missense substitutions are infrequent (14 out of 76; 18%) relative to stop-gain (29 out of 76; 38%), and splicing (33 out of 76; 43%) mutations. Where known, mutation origin was de novo in 48 out of 64 individuals (75%), dominantly inherited in 12 out of 64 (19%), and due to proven germline mosaicism in four out of 64 (6%). Highly penetrant clinical features include, microcephaly, first and second arch craniofacial malformations, and hearing loss; esophageal atresia is present in an estimated ∼27%. Microcephaly is virtually universal in childhood, with some adults exhibiting late "catch-up" growth and normocephaly at maturity. Occasionally reported anomalies, include vestibular and ossicular malformations, reduced mouth opening, atrophy of cerebral white matter, structural brain malformations, and epibulbar dermoid. All reported EFTUD2 mutations can be found in the EFTUD2 mutation database (http://databases.lovd.nl/shared/genes/EFTUD2).


Asunto(s)
Anomalías Múltiples/genética , Pérdida Auditiva/genética , Discapacidad Intelectual/genética , Disostosis Mandibulofacial/genética , Microcefalia/genética , Mutación , Factores de Elongación de Péptidos/genética , Ribonucleoproteína Nuclear Pequeña U5/genética , Anomalías Múltiples/diagnóstico , Anomalías Múltiples/patología , Secuencias de Aminoácidos , Bases de Datos Genéticas , Expresión Génica , Haploinsuficiencia , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/patología , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/patología , Disostosis Mandibulofacial/diagnóstico , Disostosis Mandibulofacial/patología , Microcefalia/diagnóstico , Microcefalia/patología , Modelos Moleculares , Datos de Secuencia Molecular , Penetrancia , Fenotipo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Empalme del ARN , Empalmosomas/genética
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