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1.
Am J Med Genet A ; 191(5): 1412-1417, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36863699

RESUMEN

We report three unrelated individuals, each exposed to maternal autoantibodies during gestation and found to have elevated very long-chain fatty acids (VLCFAs) in the newborn period after screening positive by California newborn screening (NBS) for X-linked adrenoleukodystrophy (ALD). Two probands presented with clinical and laboratory features of neonatal lupus erythematosus (NLE); the third had features suggestive of NLE and a known maternal history of Sjogren's syndrome and rheumatoid arthritis. In all three individuals, subsequent biochemical and molecular evaluation for primary and secondary peroxisomal disorders was nondiagnostic with normalization of VLCFAs by 15 months of age. These cases add to the expanding differential diagnosis to consider in newborns who screen positive for ALD via elevated C26:0-lysophosphatidylcholine. Though the pathophysiology of how transplacental maternal anti-Ro antibodies damage fetal tissue is not well-understood, we postulate that the VLCFA elevations reflect a systemic inflammatory response and secondary peroxisomal dysfunction that improves once maternal autoantibodies wane after birth. Additional evaluation of this phenomenon is warranted to better understand the intricate biochemical, clinical, and possible therapeutic overlap between autoimmunity, inflammation, peroxisomal dysfunction, and human disease.


Asunto(s)
Adrenoleucodistrofia , Lupus Eritematoso Sistémico , Humanos , Recién Nacido , Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/complicaciones , Tamizaje Neonatal , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/complicaciones , Autoanticuerpos
2.
Am J Med Genet A ; 191(6): 1492-1501, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36883293

RESUMEN

Although decreased citrulline is used as a newborn screening (NBS) marker to identify proximal urea cycle disorders (UCDs), it is also a feature of some mitochondrial diseases, including MT-ATP6 mitochondrial disease. Here we describe biochemical and clinical features of 11 children born to eight mothers from seven separate families who were identified with low citrulline by NBS (range 3-5 µM; screening cutoff >5) and ultimately diagnosed with MT-ATP6 mitochondrial disease. Follow-up testing revealed a pattern of hypocitrullinemia together with elevated propionyl-(C3) and 3-hydroxyisovaleryl-(C5-OH) acylcarnitines, and a homoplasmic pathogenic variant in MT-ATP6 in all cases. Single and multivariate analysis of NBS data from the 11 cases using Collaborative Laboratory Integrated Reports (CLIR; https://clir.mayo.edu) demonstrated citrulline <1st percentile, C3 > 50th percentile, and C5-OH >90th percentile when compared with reference data, as well as unequivocal separation from proximal UCD cases and false-positive low citrulline cases using dual scatter plots. Five of the eight mothers were symptomatic at the time of their child(ren)'s diagnosis, and all mothers and maternal grandmothers evaluated molecularly and biochemically had a homoplasmic pathogenic variant in MT-ATP6, low citrulline, elevated C3, and/or elevated C5-OH. All molecularly confirmed individuals (n = 17) with either no symptoms (n = 12), migraines (n = 1), or a neurogenic muscle weakness, ataxia, and retinitis pigmentosa (NARP) phenotype (n = 3) were found to have an A or U mitochondrial haplogroup, while one child with infantile-lethal Leigh syndrome had a B haplogroup.


Asunto(s)
Enfermedades Mitocondriales , ATPasas de Translocación de Protón Mitocondriales , Tamizaje Neonatal , Humanos , Recién Nacido , ATPasas de Translocación de Protón Mitocondriales/genética , Enfermedades Mitocondriales/sangre , Enfermedades Mitocondriales/diagnóstico , Enfermedades Mitocondriales/genética , Citrulina/sangre , Linaje , Trastornos Innatos del Ciclo de la Urea/diagnóstico
3.
Am J Med Genet A ; 185(6): 1848-1853, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33683010

RESUMEN

We report three unrelated probands, two male and one female, diagnosed with Aicardi-Goutières syndrome (AGS) after screening positive on California newborn screening (CA NBS) for X-linked adrenoleukodystrophy (X-ALD) due to elevated C26:0 lysophosphatidylcholine (C26:0-LPC). Follow-up evaluation was notable for elevated C26:0, C26:1, and C26:0/C22:0 ratio, and normal red blood cell plasmalogens levels in all three probands. Diagnoses were confirmed by molecular sequencing prior to 12 months of age after clinical evaluation was inconsistent with X-ALD or suggestive of AGS. For at least one proband, the early diagnosis of AGS enabled candidacy for enrollment into a therapeutic clinical trial. This report demonstrates the importance of including AGS on the differential diagnosis for individuals who screen positive for X-ALD, particularly infants with abnormal neurological features, as this age of onset would be highly unusual for X-ALD. While AGS is not included on the Recommended Universal Screening Panel, affected individuals can be identified early through state NBS programs so long as providers are aware of a broader differential that includes AGS. This report is timely, as state NBS algorithms for X-ALD are actively being established, implemented, and refined.


Asunto(s)
Adrenoleucodistrofia/sangre , Enfermedades Autoinmunes del Sistema Nervioso/sangre , Enfermedades Genéticas Ligadas al Cromosoma X/sangre , Tamizaje Neonatal , Malformaciones del Sistema Nervioso/sangre , Adrenoleucodistrofia/complicaciones , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/patología , Enfermedades Autoinmunes del Sistema Nervioso/complicaciones , Enfermedades Autoinmunes del Sistema Nervioso/genética , Enfermedades Autoinmunes del Sistema Nervioso/patología , Pruebas con Sangre Seca , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/complicaciones , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Humanos , Lactante , Recién Nacido , Lisofosfatidilcolinas/sangre , Masculino , Malformaciones del Sistema Nervioso/complicaciones , Malformaciones del Sistema Nervioso/genética , Malformaciones del Sistema Nervioso/patología , Espectrometría de Masas en Tándem
4.
Inorg Chem ; 56(8): 4496-4504, 2017 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-28383884

RESUMEN

The defective fluorite-related Y3NbO7 host lattice was doped with Eu3+ ions to understand the influence of spark plasma sintering (SPS) process on this host lattice. The intrinsic disorder due to the occurrence of oxygen vacancies results in amorphous-type responses of the luminescent cations, and the spectral distribution varies as a function of the niobium content. Two spectral fingerprints of europium emissions were clearly enhanced. The correlation between luminescence, X-ray diffraction, and electron diffraction characterizations shows the existence of local inhomogeneity. Indeed, the particular nonequilibrium sintering conditions allowed pointing out a lack of miscibility within the Y3NbO7 solid solution domain. Thus, the SPS pellet is a composite of two extreme compositions. This phase demixing is mainly induced by the pressure coupled with a current effect that makes possible ionic migration in this Y3NbO7 ionic conductive matrix.

5.
Osteoarthritis Cartilage ; 24(4): 688-97, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-26596790

RESUMEN

OBJECTIVE: Prevalence of ankle osteoarthritis (OA) is lower than that of knee OA, however, the molecular mechanisms underlying the difference remain unrevealed. In the present study, we developed mouse ankle OA models for use as tools to investigate pathophysiology of ankle OA and molecular characteristics of ankle cartilage. DESIGN: We anatomically and histologically examined ankle and knee joints of C57BL/6 mice, and compared them with human samples. We examined joints of 8-week-old and 25-month-old mice. For experimental models, we developed three different ankle OA models: a medial model, a lateral model, and a bilateral model, by resection of respective structures. OA severity was evaluated 8 weeks after the surgery by safranin O staining, and cartilage degradation in the medial model was sequentially examined. RESULTS: Anatomical and histological features of human and mouse ankle joints were comparable. Additionally, the mouse ankle joint was more resistant to cartilage degeneration with aging than the mouse knee joint. In the medial model, the tibiotalar joint was markedly affected while the subtalar joint was less degenerated. In the lateral model, the subtalar joint was mainly affected while the tibiotalar joint was less altered. In the bilateral model, both joints were markedly degenerated. In the time course of the medial model, TdT-mediated dUTP nick end labeling (TUNEL) staining and Adamts5 expression were enhanced at early and middle stages, while Mmp13 expression was gradually increased during the OA development. CONCLUSION: Since human and mouse ankles are comparable, the present models will contribute to ankle OA pathophysiology and general cartilage research in future.


Asunto(s)
Articulación del Tobillo/anatomía & histología , Artritis Experimental/etiología , Inestabilidad de la Articulación/complicaciones , Osteoartritis/etiología , Envejecimiento/patología , Animales , Articulación del Tobillo/diagnóstico por imagen , Artritis Experimental/diagnóstico por imagen , Artritis Experimental/patología , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/patología , Progresión de la Enfermedad , Femenino , Humanos , Articulación de la Rodilla/anatomía & histología , Articulación de la Rodilla/patología , Ligamentos Articulares/cirugía , Masculino , Ratones Endogámicos C57BL , Osteoartritis/diagnóstico por imagen , Osteoartritis/patología , Especificidad de la Especie , Tendones/cirugía , Microtomografía por Rayos X/métodos
7.
Opt Express ; 22(19): 23034-42, 2014 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-25321774

RESUMEN

We show experimentally that poly-crystalline TiO2 spheres, 20-30 µm in diameter, exhibit a magnetic dipole Mie resonance in the terahertz (THz) frequency band (1.0-1.6 THz) with a narrow line-width (<40 GHz). We detect and investigate the magnetic dipole and electric dipole resonances in single high-permittivity TiO2 microspheres, using a near-field probe with a sub-wavelength (~λ/50) size aperture and THz time-domain spectroscopy technique. The Mie resonance signatures are observed in the electric field amplitude and phase spectra, as well as in the electric field distribution near the microspheres. The narrow line-width and the sub-wavelength size (λ/10) make the TiO2 microspheres excellent candidates for realizing low-loss THz metamaterials.


Asunto(s)
Simulación por Computador , Microesferas , Espectroscopía de Terahertz/instrumentación , Titanio/química , Diseño de Equipo , Radiación Terahertz
8.
J Investig Med High Impact Case Rep ; 12: 23247096241267154, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39143735

RESUMEN

Here, we report an individual, eventually diagnosed with HMG-CoA synthase deficiency, who presented with a cyclic vomiting phenotype. HMG-CoA synthase deficiency is a rare disorder affecting ketone body synthesis in which affected individuals typically present at a young age with hypoketotic hypoglycemia, lethargy, encephalopathy, and hepatomegaly, usually triggered by catabolism (e.g., infection or prolonged fasting). This individual presented with recurrent episodes of vomiting and lethargy, often associated with hypoglycemia or hyperglycemia, at 3 years of age. Metabolic labs revealed nonspecific abnormalities in her urine organic acids (showing mild elevation of dicarboxylic acids with relatively low excretion of ketones) and a normal acylcarnitine profile. Given her clinical presentation, as well as a normal upper gastrointestinal series, esophagogastroduodenoscopy with biopsies, and abdominal ultrasound, she was diagnosed with cyclic vomiting syndrome at 3 years of age. Molecular testing completed at 7 years of age revealed a previously reported pathogenic sequence variant (c.1016+1G>A) and a novel likely pathogenic deletion (1.57 kB deletion, including exon 1) within HMGCS2 consistent with HMG-CoA synthase deficiency. This individual's presentation, mimicking cyclic vomiting syndrome, widens the clinical spectrum of HMG-CoA synthase deficiency. In addition, this case highlights the importance of molecular genetic testing in such presentations, as this rare disorder lacks specific metabolic markers.


Asunto(s)
Hidroximetilglutaril-CoA Sintasa , Vómitos , Humanos , Vómitos/etiología , Femenino , Hidroximetilglutaril-CoA Sintasa/genética , Hidroximetilglutaril-CoA Sintasa/deficiencia , Preescolar , Biomarcadores/orina , Biomarcadores/sangre , Errores Innatos del Metabolismo Lipídico/diagnóstico , Errores Innatos del Metabolismo Lipídico/genética , Errores Innatos del Metabolismo Lipídico/complicaciones , Diagnóstico Diferencial , Acetil-CoA C-Acetiltransferasa/deficiencia , Errores Innatos del Metabolismo de los Aminoácidos
9.
Nat Mater ; 11(4): 301-5, 2012 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-22367002

RESUMEN

The composition of amorphous oxide semiconductors, which are well known for their optical transparency, can be tailored to enhance their absorption and induce photoconductivity for irradiation with green, and shorter wavelength light. In principle, amorphous oxide semiconductor-based thin-film photoconductors could hence be applied as photosensors. However, their photoconductivity persists for hours after illumination has been removed, which severely degrades the response time and the frame rate of oxide-based sensor arrays. We have solved the problem of persistent photoconductivity (PPC) by developing a gated amorphous oxide semiconductor photo thin-film transistor (photo-TFT) that can provide direct control over the position of the Fermi level in the active layer. Applying a short-duration (10 ns) voltage pulse to these devices induces electron accumulation and accelerates their recombination with ionized oxygen vacancy sites, which are thought to cause PPC. We have integrated these photo-TFTs in a transparent active-matrix photosensor array that can be operated at high frame rates and that has potential applications in contact-free interactive displays.

10.
Opt Express ; 21(12): 14047-55, 2013 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-23787594

RESUMEN

We propose a hogel overlapping method for the holographic printer to enhance the lateral resolution of holographic stereograms. The hogel size is directly related to the lateral resolution of the holographic stereogram. Our analysis by computer simulation shows that there is a limit to decreasing the hogel size while printing holographic stereograms. Instead of reducing the size of hogel, the lateral resolution of holographic stereograms can be enhanced by printing overlapped hogels, which makes it possible to take advantage of multiplexing property of the volume hologram. We built a holographic printer, and recorded two holographic stereograms using the conventional and proposed overlapping methods. The images and movies of the holographic stereograms experimentally captured were compared between the conventional and proposed methods. The experimental results confirm that the proposed hogel overlapping method improves the lateral resolution of holographic stereograms compared to the conventional holographic printing method.


Asunto(s)
Diseño Asistido por Computadora , Holografía/instrumentación , Aumento de la Imagen/instrumentación , Imagenología Tridimensional/instrumentación , Modelos Teóricos , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Dispersión de Radiación
11.
Pharmacopsychiatry ; 46(4): 137-46, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23364873

RESUMEN

Given the shortage of studies on parental perceived benefits of OROS-methylphenidate treatment in Asian populations, we assessed parental response to OROS-methylphenidate treatment of Korean children with attention-deficit/hyperactivity disorder (ADHD), in relation to children's academic performance and behavioral symptoms as well as parental rearing stress and depressive symptoms.We enrolled 132 medication-naïve children with ADHD into a multicenter, open-label, 12-week trial of OROS-MPH. The outcome measures were the ADHD rating scale-IV (ADHD-RS), the comprehensive attention test and academic performance rating scale, and the clinical global impression (CGI)-severity/improvement instrument (for the children) and Beck depression inventory and parenting stress index (for their parents).We found parent-perceived improvements in children's ADHD-related behavioral symptoms and academic function and their parents' depressive symptoms and parenting stress. Investigator-rated ADHD symptoms and subjects' neuropsychological function were also improved (p<0.001).Parents of Korean children with ADHD perceive that OROS-methylphenidate treatment improves their children's academic function and behavior as well as their own child-rearing stress and emotional state. These findings must be interpreted with caution, due to a non-comparative open-label trial.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Metilfenidato/uso terapéutico , Padres/psicología , Adulto , Pueblo Asiatico , Atención/fisiología , Trastorno por Déficit de Atención con Hiperactividad/psicología , Cuidadores/psicología , Estimulantes del Sistema Nervioso Central/administración & dosificación , Estimulantes del Sistema Nervioso Central/efectos adversos , Niño , Depresión/psicología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Escolaridad , Femenino , Humanos , Masculino , Metilfenidato/administración & dosificación , Metilfenidato/efectos adversos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Responsabilidad Parental/psicología , República de Corea , Estrés Psicológico/psicología , Resultado del Tratamiento
12.
Nat Mater ; 10(8): 625-30, 2011 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-21743450

RESUMEN

Numerous candidates attempting to replace Si-based flash memory have failed for a variety of reasons over the years. Oxide-based resistance memory and the related memristor have succeeded in surpassing the specifications for a number of device requirements. However, a material or device structure that satisfies high-density, switching-speed, endurance, retention and most importantly power-consumption criteria has yet to be announced. In this work we demonstrate a TaO(x)-based asymmetric passive switching device with which we were able to localize resistance switching and satisfy all aforementioned requirements. In particular, the reduction of switching current drastically reduces power consumption and results in extreme cycling endurances of over 10(12). Along with the 10 ns switching times, this allows for possible applications to the working-memory space as well. Furthermore, by combining two such devices each with an intrinsic Schottky barrier we eliminate any need for a discrete transistor or diode in solving issues of stray leakage current paths in high-density crossbar arrays.

13.
Nanotechnology ; 23(22): 225702, 2012 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-22572757

RESUMEN

We report a physical model for multilevel switching in oxide-based bipolar resistive memory (ReRAM). To confirm the validity of the model, we conduct experiments with tantalum-oxide-based ReRAM of which multi-resistance levels are obtained by reset voltage modifications. It is also noticeable that, in addition to multilevel switching capability, the ReRAM exhibits extremely different switching timescales, i.e. of the order of 10(-7) s to 10(0) s, with regard to reset voltages of only a few volts difference which can be well explained by our model. It is demonstrated that with this simple model, multilevel switching behavior in oxide bipolar ReRAM can be described not only qualitatively but also quantitatively.

15.
Nano Lett ; 10(5): 1671-6, 2010 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-20377269

RESUMEN

We investigate peculiar dopant deactivation behaviors of Si nanostrucures with first principle calculations and reveal that surface dangling bonds (SDBs) on Si nanostructures could be fundamental obstacles in nanoscale doping. In contrast to bulk Si, as the size of Si becomes smaller, SDBs on Si nanostructures prefer to be charged and asymmetrically deactivate n- and p-type doping. The asymmetric dopant deactivation in Si nanostructures is ascribed to the preference for negatively charged SDBs as a result of a larger quantum confinement effect on the conduction band. On the basis of our results, we show that the control of the growth direction of silicon nanowire as well as surface passivation is very important in preventing dopant deactivation.


Asunto(s)
Modelos Químicos , Modelos Moleculares , Nanoestructuras/química , Nanoestructuras/ultraestructura , Silicio/química , Sitios de Unión , Simulación por Computador , Sustancias Macromoleculares/química , Conformación Molecular , Tamaño de la Partícula , Propiedades de Superficie
16.
Mol Genet Metab Rep ; 27: 100765, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34277355

RESUMEN

The phenotype of individuals with glycogen storage disease (GSD) IX appears to be highly variable, even within subtypes. Features include short stature, fasting hypoglycemia with ketosis, hepatomegaly, and transaminitis. GSD IXɑ2 is caused by hemizygous pathogenic variants in PHKA2, and results in deficiency of the phosphorylase kinase enzyme, particularly in the liver. Like other GSDs, GSD IXɑ2 can present with hypoglycemia and post-prandial lactic acidosis, but has never been reported in a newborn, nor with lactic acidosis as the presenting feature. Here we describe the clinical presentation and course of a newborn boy with profound neonatal lactic and metabolic acidosis, renal tubulopathy, and sensorineural hearing loss (SNHL) diagnosed with GSD IXɑ2 through exome sequencing. Review of the literature suggests this case represents an atypical and severe presentation of GSD IXɑ2 and proposes expansion of the phenotype to include neonatal lactic acidosis and renal tubulopathy.

17.
Osteoarthritis Cartilage ; 17(8): 1065-75, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19254740

RESUMEN

OBJECTIVE: Although SOX9 is a key molecule for chondrogenic differentiation, little is known about the upstream signal. The present study attempted to identify transcription factors to induce SOX9 expression and examined the mechanism. METHODS: Sequences of about 1 kb of 5'-end flanking regions were compared between human and mouse SOX9 genes. In vivo localization was examined by immunohistochemistry in the limb cartilage of fetal mice. Promoter activities of the SOX9, SOX6, and type II collagen (COL2A1) genes were determined in human non-chondrogenic HeLa cells and mouse chondrogenic ATDC5 cells transfected with a luciferase-reporter gene containing the promoter fragments. Protein-DNA binding was examined by electrophoretic mobility shift and chromatin immunoprecipitation assays. The chondrogenic differentiation was assessed by endogenous SOX9, SOX6, and COL2A1 mRNA levels, and by Alcian blue staining and alkaline phosphatase activity. RESULTS: Among transcription factors whose binding motifs were identified in the highly-conserved regions between human and mouse SOX9 promoters, a nuclear factor kappa B (NF-kappaB) member RelA strongly activated the promoter activity. RelA and SOX9 were co-localized in the limb cartilage. Deletion, mutagenesis, and tandem-repeat analyses identified the core region responsive to RelA at the NF-kappaB binding motif to be around -250bp of the human SOX9 promoter, and this was confirmed to show specific binding to RelA. RelA induced the chondrogenic differentiation parameters in HeLa and ATDC5 cells. CONCLUSION: We have identified RelA as a transcriptional factor for SOX9 induction and chondrogenic differentiation via binding to an NF-kappaB binding motif in the SOX9 promoter.


Asunto(s)
Colágeno Tipo II/metabolismo , FN-kappa B/genética , Regiones Promotoras Genéticas/genética , Factor de Transcripción SOX9/metabolismo , Factores de Transcripción/genética , Animales , Células Cultivadas , Colágeno Tipo II/genética , Humanos , Inmunohistoquímica , Ratones , FN-kappa B/metabolismo , Factor de Transcripción SOX9/genética , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/metabolismo , Factores de Transcripción/metabolismo
18.
J Clin Invest ; 107(3): 295-304, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11160153

RESUMEN

Vertebrate skeletogenesis requires a well-coordinated transition from chondrogenesis to osteogenesis. Hypertrophic chondrocytes in the growth plate play a pivotal role in this transition. Parathyroid hormone-related peptide (PTHrP), synthesized in the periarticular growth plate, regulates the site at which hypertrophy occurs. By comparing PTH/PTHrP receptor(-/-)/wild-type (PPR(-/-)/wild-type) chimeric mice with IHH(-/-);PPR(-/-)/wild-type chimeric and IHH(-/-)/wild-type chimeric mice, we provide in vivo evidence that Indian hedgehog (IHH), synthesized by prehypertrophic and hypertrophic chondrocytes, regulates the site of hypertrophic differentiation by signaling to the periarticular growth plate and also determines the site of bone collar formation in the adjacent perichondrium. By providing crucial local signals from prehypertrophic and hypertrophic chondrocytes to both chondrocytes and preosteoblasts, IHH couples chondrogenesis to osteogenesis in endochondral bone development.


Asunto(s)
Desarrollo Óseo/fisiología , Proteínas/fisiología , Transactivadores , Animales , Cartílago/embriología , Cartílago/crecimiento & desarrollo , Diferenciación Celular , Condrocitos/metabolismo , Condrocitos/fisiología , Condrogénesis , Inducción Embrionaria , Placa de Crecimiento/embriología , Placa de Crecimiento/crecimiento & desarrollo , Proteínas Hedgehog , Hibridación in Situ , Ratones , Osteogénesis , Proteína Relacionada con la Hormona Paratiroidea , Biosíntesis de Proteínas , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/análisis , Transducción de Señal , Tibia/embriología , Tibia/crecimiento & desarrollo
19.
Mech Dev ; 81(1-2): 151-61, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10330492

RESUMEN

A number of studies suggest a role for PTHrP and the classical PTH/PTHrP receptor (type I) in one of the first differentiation processes in mouse embryogenesis, i.e. the formation of parietal endoderm (PE). We previously reported that although in type I receptor (-/-) embryos PE formation seemed normal, the embryos were smaller from at least day 9.5 p.c. and 60% had died before day 12.5 p.c. Here we show that the observed growth defect commences even earlier, at day 8.5 p.c. Using two novel antibodies, we show that the expression of the type I receptor protein at this stage is confined to extraembryonic endoderm only. In addition, we show that large amounts of PTHrP protein are present in the adjacent trophoblast giant cells, suggesting a paracrine interaction of PTHrP and the type I PTH/PTHrP receptor in PE formation. The involvement in PE differentiation of other recently described receptors for PTHrP would explain a possible redundancy for the type I receptor in PE formation. However, deletion of the type I PTH/PTHrP receptor in ES cells by homologous recombination completely prevents PTHrP-induced PE differentiation. Based upon these observations, we propose that PTHrP and the type I PTH/PTHrP receptor, although not required for the initial formation of PE, are required for its proper differentiation and/or functioning.


Asunto(s)
Ectodermo/fisiología , Proteínas/fisiología , Receptores de Hormona Paratiroidea/fisiología , Animales , Western Blotting , Células COS , Células Cultivadas , Embrión de Mamíferos/metabolismo , Embrión de Mamíferos/patología , Femenino , Técnica del Anticuerpo Fluorescente , Regulación del Desarrollo de la Expresión Génica , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Proteína Relacionada con la Hormona Paratiroidea , Proteínas/análisis , Receptor de Hormona Paratiroídea Tipo 1 , Receptores de Hormona Paratiroidea/análisis , Células Madre/metabolismo , Trombomodulina/metabolismo , Factores de Tiempo , Transfección
20.
J Bone Miner Res ; 15(6): 1033-44, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10841172

RESUMEN

The localization of PTH/PTH-related peptide (PTHrP) receptor (PTHR) has traditionally been performed by autoradiography. Specific polyclonal antibodies to peptides unique to the PTHR are now available, which allow a more precise localization of the receptor in cells and tissues. We optimized the IHC procedure for the rat PTHR using 5-microm sections of paraffin-embedded rat kidney, liver, small intestine, uterus, and ovary. Adjacent sections were analyzed for the presence of PTHR mRNA (by in situ hybridization) and PTHrP peptide. A typical pattern of staining for both receptor protein and mRNA was observed in kidney in cells lining the proximal tubules and collecting ducts. In uterus and gut, the receptor and its mRNA are present in smooth muscle layers (PTHrP target) and in glandular cuboidal cells and surface columnar epithelium. This suggests that PTH, or more likely PTHrP, plays a role in surface/secretory epithelia that is as yet undefined. In the ovary, PTHR was readily detectable in the thecal layer of large antral follicles and oocytes, and was present in the cytoplasm and/or nucleus of granulosa cells, regions that also contained receptor transcripts. PTHR protein and mRNA were found in the liver in large hepatocytes radiating outward from central veins. Immunoreactive cells were also present around the periphery of the liver but not within two or three cell layers of the surface. Clear nuclear localization of the receptor protein was present in liver cells in addition to the expected cytoplasmic/peripheral staining. PTHR immunoreactivity was present in the nucleus of some cells in every tissue examined. RT-PCR confirmed the presence of PTHR transcripts in these same tissues. Examination of the hindlimbs of PTHR gene-ablated mice showed no reaction to this antibody, whereas hindlimbs from their wild-type littermates stained positively. The results emphasize that the PTHR is highly expressed in diverse tissues and, in addition, show that the receptor protein itself can be localized to the cell nucleus. Nuclear localization of the receptor suggests that there is a role for PTH and/or PTHrP in the regulation of nuclear events, either on the physical environment (nucleoskeleton) or directly on gene expression.


Asunto(s)
Proteínas/análisis , Receptores de Hormona Paratiroidea/análisis , Secuencia de Aminoácidos , Animales , Western Blotting/métodos , Núcleo Celular/química , Femenino , Expresión Génica , Humanos , Intestino Delgado/metabolismo , Intestino Delgado/patología , Riñón/metabolismo , Riñón/patología , Ligandos , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Noqueados , Datos de Secuencia Molecular , Ovario/metabolismo , Ovario/patología , Proteína Relacionada con la Hormona Paratiroidea , Proteínas/genética , Ratas , Ratas Sprague-Dawley , Receptor de Hormona Paratiroídea Tipo 1 , Receptores de Hormona Paratiroidea/genética , Tibia/metabolismo , Tibia/patología , Distribución Tisular , Útero/metabolismo , Útero/patología
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