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1.
J Phys Chem A ; 122(6): 1574-1583, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29356525

RESUMEN

In this work we study the double ionization yields and kinetic energy spectra of a two-electron spherical quantum dot (QD) exposed in laser fields. The theoretical description is based on an ab initio nonperturbative configuration interaction theory capable of describing the two-electron QD dynamics in THz and mid-IR ultrashort laser fields. The QD's confinement potential is approximated to have a Gaussian-like spatial dependence. We have found that significant variations of the two-electron kinetic energy patterns and two-photon double ionization yields occur as we vary the QD's size. For a given laser pulse, the double ionization yield increases by orders of magnitude when the dot size is reduced. The size of the QD determines the sequential or direct character of the two-photon double ionization process. Provided that it is energetically allowed, the sequential two-photon double ionization process, requiring minimal interelectronic correlations, becomes dominant over the direct one. In the sequential regime, the corresponding two-electron kinetic energy spectrum changes from a broadened single-peaked to a doubly peaked one. Moreover, we also have identified features in the spectrum that are distinctively different than those in its atomic counterpart.

2.
Materials (Basel) ; 16(4)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36837035

RESUMEN

Using an ab initio, time-dependent calculational method, we study the non-linear dynamics of a two-electron quantum dot in the presence of ultrashort Thz laser pulses. The analysis of the contribution of the various partial waves to two-electron joint radial and energy distribution patterns revealed strongly correlated electron ejection channels. In the double-ionization process, regardless of the photon energy, the two-electron wave packets are born and remain concentrated until the pulse's peak; at later times, and depending on the photon energy of the field, distinctly different patterns emerge. Our calculations also showed the gradual transition of the radial and energy patterns from a single-peak to a doubly peaked structure, associated with the direct and the sequential double-ionization mechanisms, respectively.

3.
Biomolecules ; 13(6)2023 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-37371535

RESUMEN

Asthma is a heterogeneous disease, characterized by chronic inflammation and oxidative stress of the airways. Several inflammatory pathways including activation of the receptor for advanced glycation end products (RAGE) have been described in the course of the disease. DJ-1 is a redox-sensitive protein with multifaceted roles in mast cell homeostasis and an emerging role in the pathogenesis of asthma. Moreover, cardiac function abnormalities have been described via echocardiography in patients with asthma. The main aim of this study was to investigate the plasma levels of RAGE, its ligands and DJ-1 in asthmatic patients pre- and post-treatment along with echocardiographic indices of cardiovascular function. The study population was divided into two groups. Group A included 13 patients with newly diagnosed bronchial asthma who were free of treatment for at least two weeks and Group B included 12 patients without asthma. An echocardiography examination was performed on all patients. The plasma levels of RAGE, its ligands (AGEs, S100A12, S100B, S100A8/A9), the interleukins (IL-6, IL-1ß) and DJ-1 were measured. No differences were noted among the two groups for baseline characteristics and echocardiographic indices of cardiac function. In Group A, 31% suffered from mild asthma, 54% from moderate asthma and 15% from severe asthma. Plasma levels of IL-6, AGEs and AGE/RAGE ratio were increased and those of S100A12 and DJ-1 were decreased in asthmatics. Pharmacotherapy with corticosteroids/ß2-agonists decreased IL-6, and AGEs, and increased DJ-1. In search of novel approaches in diagnosing and treating patients with asthma, S100A12, ratio AGE/sRAGE, and DJ-1 in addition to IL-6 may prove to be useful tools.


Asunto(s)
Asma , Proteína S100A12 , Humanos , Ligandos , Interleucina-6 , Receptor para Productos Finales de Glicación Avanzada , Productos Finales de Glicación Avanzada , Asma/diagnóstico por imagen , Asma/tratamiento farmacológico , Ecocardiografía
4.
Eur J Med Genet ; 64(2): 104141, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33450337

RESUMEN

Multiple endocrine neoplasia type 2 (MEN2) is a dominantly inherited condition with defined correlations between the genetic variant and clinical presentations. The location of pathogenic variants in the RET gene is a significant determinant of disease presentation and is associated with variable gene activation. Heterozygous pathogenic variants in codon 634 result in earlier onset of medullary thyroid carcinoma and higher incidence of phaeochromocytoma. Here we describe a consanguineous family with MEN2A that includes two children homozygous for the established pathogenic variant p. Cys634Trp. Both parents and a sibling were confirmed to being heterozygotes. Previous reports of biallelic or multiple RET variants have been limited to weakly activating variants. We present the first report of individuals homozygous for the highly activating RET p. Cys634Trp pathogenic variant and discuss disease severity and onset in this rare occurrence.


Asunto(s)
Neoplasia Endocrina Múltiple Tipo 2a/genética , Mutación Missense , Proteínas Proto-Oncogénicas c-ret/genética , Adolescente , Adulto , Niño , Consanguinidad , Femenino , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple Tipo 2a/patología , Linaje
5.
Rev Med Interne ; 42(4): 258-268, 2021 Apr.
Artículo en Francés | MEDLINE | ID: mdl-32868117

RESUMEN

Infections are a frequent cause of cerebral vasculitis, important to diagnose because a specific treatment may be required. Infection-associated vasculitis can be caused by angiotropic pathogens (varicella zoster virus, syphilis, aspergillus). They can be associated with subarachnoidal meningitis (tuberculosis, pyogenic meningitis, cysticercosis). They can appear contiguously to sinuses or orbital infection (aspergillosis, mucormycosis). Finally, they also may be due to an immune mechanism in the context of chronic infections (hepatitis B virus, hepatitis C virus, human immunodeficiency virus). Cerebral vasculitis are severe conditions and their prognosis is directly linked to early recognition and diagnosis. Infectious causes must therefore be systematically considered ahead of cerebral vasculitis, and the appropriate investigations must be determined according to the patient's clinical context. We propose here an update on the infectious causes of cerebral vasculitis, their diagnosis modalities, and therapeutic options.


Asunto(s)
Infecciones por VIH , Sífilis , Tuberculosis , Vasculitis del Sistema Nervioso Central , Herpesvirus Humano 3 , Humanos , Vasculitis del Sistema Nervioso Central/complicaciones , Vasculitis del Sistema Nervioso Central/diagnóstico
6.
Rev Med Interne ; 41(6): 360-367, 2020 Jun.
Artículo en Francés | MEDLINE | ID: mdl-31982256

RESUMEN

INTRODUCTION: Patients with psychiatric disorders suffer from a higher rate of somatic disorders than those without psychiatric disorder, often inappropriately managed. Our study aimed to describe patients with psychiatric comorbidity in post-emergency internal medicine units and to compare their length of hospital stay to patients without psychiatric disease. METHODS: This French cross sectional study used the data warehouse of the greater Paris hospitals. It included, all patients hospitalized through the emergency department in 9 internal medicine departments during the year 2017. Psychiatric disorders and the burden of somatic disorders (Charlson score) were determined through diagnostic coding. Charlson score and hospital length of stay were compared between patients with and without psychiatric comorbidity. RESULTS: In total, 8981 hospital stays (8001 patients) were included, 1867 (21%) with psychiatric comorbidity. After adjusting for age, gender, hospital and main diagnosis, the Charlson score was on average 0.68 higher in the psychiatric comorbidity group (P<0.001) and the length of hospital stay was 30% higher after further adjustment on the Charlson score (P<0.001). These differences were consistent for each main diagnosis. CONCLUSION: Patients with psychiatric comorbidity are frequent in post-emergency internal medicine wards. They experience longer hospital stays, only partly related with a higher burden of somatic disorders. Special attention should be paid to this vulnerable population.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Medicina Interna/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Trastornos Mentales/epidemiología , Transferencia de Pacientes/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Estudios Transversales , Femenino , Humanos , Medicina Interna/organización & administración , Masculino , Persona de Mediana Edad , Paris/epidemiología , Estudios Retrospectivos
7.
Eur J Hum Genet ; 14(2): 151-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16319823

RESUMEN

Heterozygous mutations of the homeobox genes ALX4 and MSX2 cause skull defects termed enlarged parietal foramina (PFM) and cranium bifidum (CB); a single MSX2 mutation has been documented in a unique craniosynostosis (CRS) family. However, the relative mutational contribution of these genes to PFM/CB and CRS is not known and information on genotype-phenotype correlations is incomplete. We analysed ALX4 and MSX2 in 11 new unrelated cases or families with PFM/CB, 181 cases of CRS, and a single family segregating a submicroscopic deletion of 11p11.2, including ALX4. We explored the correlations between skull defect size and age, gene, and mutation type, and reviewed additional phenotypic manifestations. Four PFM cases had mutations in either ALX4 or MSX2; including previous families, we have identified six ALX4 and six MSX2 mutations, accounting for 11/13 familial, but only 1/6 sporadic cases. The deletion family confirms the delineation of a mental retardation locus to within 1.1 Mb region of 11p11.2. Overall, no significant size difference was found between ALX4- and MSX2-related skull defects, but the ALX4 mutation p.R218Q tends to result in persistent CB and is associated with anatomical abnormalities of the posterior fossa. We conclude that PFM caused by mutations in ALX4 and MSX2 have a similar prevalence and are usually clinically indistinguishable. Mutation screening has a high pickup rate in PFM, especially in familial cases, but is not indicated in CRS.


Asunto(s)
Cromosomas Humanos Par 11/genética , Proteínas de Unión al ADN/genética , Proteínas de Homeodominio/genética , Mutación/genética , Fenotipo , Cráneo/anomalías , Factores de Transcripción/genética , Secuencia de Bases , Cromatografía Líquida de Alta Presión , Mapeo Cromosómico , Análisis Mutacional de ADN , Cartilla de ADN , Eliminación de Gen , Humanos , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Secuencias Repetidas en Tándem/genética
11.
Eur J Hum Genet ; 11(11): 892-5, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14571277

RESUMEN

The combination of skull defects in the form of enlarged parietal foramina (PFM) and deficient ossification of the clavicles is known as parietal foramina with cleidocranial dysplasia (PFMCCD). It is considered to be distinct from classical cleidocranial dysplasia (CCD) and is listed as a separate OMIM entry (168550). So far, only two families have been reported and the molecular basis of the disorder is unknown. We present a third family with PFMCCD, comprising four affected individuals in three generations, and demonstrate that a heterozygous tetranucleotide duplication in the MSX2 homeobox gene (505_508dupATTG) segregates with the phenotype. PFMCCD is indeed aetiologically distinct from CCD, which is caused by mutations in the RUNX2 gene, but allelic with isolated PFM, in which MSX2 mutations were previously identified. Our observations highlight the role of MSX2 in clavicular development and the importance of radiological examination of the clavicles in subjects with PFM.


Asunto(s)
Clavícula/anomalías , Displasia Cleidocraneal/genética , Proteínas de Unión al ADN/genética , Osteogénesis/genética , Hueso Parietal/anomalías , Adulto , Preescolar , Clavícula/diagnóstico por imagen , Displasia Cleidocraneal/diagnóstico por imagen , Femenino , Mutación del Sistema de Lectura , Proteínas de Homeodominio , Humanos , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Hueso Parietal/diagnóstico por imagen , Linaje , Radiografía
12.
Psychiatr Genet ; 13(2): 115-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12782970

RESUMEN

OBJECTIVES: The genetic basis of schizophrenia is obscure. In an XX male patient with schizophrenia we previously showed that one X;Y translocation breakpoint was in pseudoautosomal region 1 (PAR1) with the effect that the proximal segment of PAR1 from the PAR1 boundary to acetylserotonin N-methyl transferase (ASMT) distally was triplicated in this patient. This study determined whether dosage imbalances of X-Y homologous regions in general are associated with schizophrenia. METHODS: A multiplex semi-quantitative polymerase chain reaction assay was developed to quantify MIC2 gene as a representative of PAR1 and compare it with the SYBL1 gene which maps in pseudoautosomal region 2 (PAR2) and protocadherin XY (PCDHXY), located at Xq21.3. Each of these three loci was co-amplified with the autosomal gene MSX2 using Cy5-labelled primers and the products separated by electrophoresis in polyacrylamide gels. Results were expressed as ratios of peak area of the target gene to MSX2 which served as an internal dosage control. RESULTS: Using genomes with sex chromosome aneuploidies, the method was found sensitive enough to detect a two-fold difference in gene copy number. We confirmed the MIC2 triplication in the XX male patient but found no significant difference in gene dosage of MIC2, PCDHXY and SYBL1 in a panel of 17 patients with schizophrenia compared to controls. CONCLUSIONS: No evidence was obtained for gene dosage imbalances in MIC2, PCDHXY and SYBL1 in patients with schizophrenia.


Asunto(s)
Cromosomas Humanos X/genética , Cromosomas Humanos Y/genética , Reacción en Cadena de la Polimerasa/métodos , Esquizofrenia/genética , Antígeno 12E7 , Aneuploidia , Antígenos CD/genética , Secuencia de Bases , Moléculas de Adhesión Celular/genética , Mapeo Cromosómico , Cartilla de ADN , Dosificación de Gen , Humanos , Proteínas de la Membrana/genética , Proteínas R-SNARE , Translocación Genética/genética
13.
Immunotherapy ; 5(10): 1033-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24088073

RESUMEN

The only method aiming to permanently cure allergic disorders is allergen immunotherapy. Over the last 20 years there has been great progress in understanding the mechanisms that govern allergen immunotherapy in order to meet three basic prerequisites: safety, effectiveness and compliance. In the present summary report from the European Academy of Allergology and Clinical Immunology-World Allergy Organization Congress held last June in Milan, we review key points concerning the main axes as diagnosis, novel modalities, routes and protocols, as well as two important immunotherapy fields: food and insect venom allergy.


Asunto(s)
Alergia e Inmunología , Desensibilización Inmunológica/métodos , Hipersensibilidad/inmunología , Hipersensibilidad/terapia , Alérgenos/efectos adversos , Alérgenos/inmunología , Animales , Análisis Costo-Beneficio , Desensibilización Inmunológica/tendencias , Alimentos/efectos adversos , Humanos , Hipersensibilidad/diagnóstico , Insectos , Italia , Cumplimiento de la Medicación , Ponzoñas/efectos adversos
14.
Genet Test Mol Biomarkers ; 16(5): 453-5, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22288896

RESUMEN

TMC1, a second-tier deafness gene below GJB2, is an appreciable cause of recessive nonsyndromic hearing loss (DFNB7/11) in North Africa, the Middle East, and parts of South Asia. Additionally, a single founder mutation, c.100C>T (p.Arg34X), dominates the TMC1 mutation spectrum. We investigated the frequency of TMC1 c.100C>T in a large set of British Asians with hearing loss, collectively a group with high prevalence of genetic deafness and limited routine clinical testing options beyond GJB2, on a candidate basis. An estimate of 0.21% (95% confidence interval, 0.04%-1.18%) was gained, indicating no significant enrichment in our set. Identification of the common non-GJB2 deafness genes and mutations in British Asian communities would require data from autozygosity mapping and/or massively parallel sequencing of gene panels.


Asunto(s)
Pueblo Asiatico/genética , Sordera/genética , Proteínas de la Membrana/genética , Mutación , Conexina 26 , Conexinas , Sordera/epidemiología , Sordera/etiología , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Prevalencia , Reino Unido/etnología
15.
Arch Dis Child ; 96(9): 798-803, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21586435

RESUMEN

OBJECTIVE: To determine the clinical sensitivity of DFNB1 genetic testing (analysis of the connexin 26 gene GJB2) for non-syndromic sensorineural hearing loss (SNHL) in British Pakistani children and extend to a comparison with British White children and literature data. DESIGN: Retrospective cohort study. SETTING: City of Bradford, UK. PATIENTS: Overall, 177 children (152 families) were eligible; 147 children (123 families) were British Pakistani, and 30 children (29 families) were British White. INTERVENTIONS: DFNB1 testing was offered. MAIN OUTCOME MEASURES: Detection rate for pathogenic bi-allelic GJB2 mutations. RESULTS: DFNB1 testing yielded positive results in 6.9% British Pakistani families compared with 15.4% British White families. Of 65 British Pakistani children tested (from 58 families), five children (from four families) were found to be homozygous for the common South Asian GJB2 mutation p.Trp24X. Of 14 British White children tested (from 13 families), bi-allelic pathogenic GJB2 mutations were seen in two children (from two families). CONCLUSIONS: The contribution of DFNB1 to non-syndromic SNHL in the Bradford British Pakistani children appears to be low when compared with a White peer group and White populations in general. The high prevalence of genetic deafness in this community, attributed to family structure and immigration history, points to a dilution effect in favour of other recessive deafness genes/loci.


Asunto(s)
Pueblo Asiatico/genética , Conexinas/genética , Pérdida Auditiva Sensorineural/genética , Mutación , Adolescente , Niño , Preescolar , Conexina 26 , Inglaterra/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Pérdida Auditiva Sensorineural/etnología , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Población Blanca/genética
16.
J Anat ; 204(6): 487-99, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15198690

RESUMEN

Alx4 and Msx2 encode homeodomain-containing transcription factors that show a clear functional overlap. In both mice and humans, loss of function of either gene is associated with ossification defects of the skull vault, although the major effect is on the frontal bones in mice and the parietal bones in humans. This study was undertaken to discover whether Alx4 and Msx2 show a genetic interaction in skull vault ossification, and to test the hypothesis that they interact with the pathway that includes the Fgfr genes, Twist1 and Runx2. We generated Alx4(+/-)/Msx2(+/-) double heterozygous mutant mice, interbred them to produce compound genotypes and analysed the genotype-phenotype relationships. Loss of an increasing number of alleles correlated with an incremental exacerbation of the skull vault defect; loss of Alx4 function had a marginally greater effect than loss of Msx2 and also affected skull thickness. In situ hybridization showed that Alx4 and Msx2 are expressed in the cranial skeletogenic mesenchyme and in the growing calvarial bones. Studies of the coronal suture region at embryonic day (E)16.5 revealed that Alx4 expression was decreased, but not abolished, in Msx2(-/-) mutants, and vice versa; expression of Fgfr2 and Fgfr1, but not Twist1, was reduced in both mutants at the same stage. Runx2 expression was unaffected in the coronal suture; in contrast, expression of the downstream ossification marker Spp1 was delayed. Double homozygous pups showed substantial reduction of alkaline phosphatase expression throughout the mineralized skull vault; they died at birth due to defects of the heart, lungs and diaphragm not previously associated with Alx4 or Msx2. Our observations suggest that Alx4 and Msx2 are partially functionally redundant, acting within a network of transcription factors and signalling events that regulate the rate of osteogenic proliferation and differentiation at a stage after the commitment of mesenchymal stem cells to osteogenesis.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Cráneo/embriología , Factores de Transcripción/fisiología , Animales , Animales Recién Nacidos , Proteínas de Unión al ADN/genética , Desarrollo Embrionario y Fetal/fisiología , Expresión Génica , Genotipo , Proteínas de Homeodominio , Hibridación in Situ , Ratones , Ratones Endogámicos BALB C , Ratones Mutantes , Osteogénesis/fisiología , Fenotipo , Cráneo/metabolismo , Factores de Transcripción/genética
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