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1.
Clin Exp Med ; 24(1): 11, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38244120

RESUMEN

Polycythemia Vera (PV) is typically caused by V617F or exon 12 JAK2 mutations. Little is known about Polycythemia cases where no JAK2 variants can be detected, and no other causes identified. This condition is defined as idiopathic erythrocytosis (IE). We evaluated clinical-laboratory parameters of a cohort of 56 IE patients and we determined their molecular profile at diagnosis with paired blood/buccal-DNA exome-sequencing coupled with a high-depth targeted OncoPanel to identify a possible underling germline or somatic cause. We demonstrated that most of our cohort (40/56: 71.4%) showed no evidence of clonal hematopoiesis, suggesting that IE is, in large part, a germline disorder. We identified 20 low mutation burden somatic variants (Variant allelic fraction, VAF, < 10%) in only 14 (25%) patients, principally involving DNMT3A and TET2. Only 2 patients presented high mutation burden somatic variants, involving DNMT3A, TET2, ASXL1 and WT1. We identified recurrent germline variants in 42 (75%) patients occurring mainly in JAK/STAT, Hypoxia and Iron metabolism pathways, among them: JAK3-V722I and HIF1A-P582S; a high fraction of patients (48.2%) resulted also mutated in homeostatic iron regulatory gene HFE-H63D or C282Y. By generating cellular models, we showed that JAK3-V722I causes activation of the JAK-STAT5 axis and upregulation of EPAS1/HIF2A, while HIF1A-P582S causes suppression of hepcidin mRNA synthesis, suggesting a major role for these variants in the onset of IE.


Asunto(s)
Policitemia Vera , Policitemia , Humanos , Policitemia/diagnóstico , Policitemia/genética , Policitemia Vera/genética , Mutación , Hierro , Células Germinativas
2.
Artículo en Inglés | MEDLINE | ID: mdl-32347669

RESUMEN

This clinical study evaluated the survival of monolithic lithium disilicate (MLD) single crowns. Between January-2010 and January-2015, 87 patients received 122 MLD (IPS e.max CAD) single crowns on natural teeth with knife-edge finish lines that were adhesively bonded (Maxcem Elite). MLD single crowns (N=122) were bonded on 60 molars (maxilla:35, mandible:25), 53 premolars (maxilla:27, mandible:26), 4 canines (maxilla:2, mandible:2), 3 laterals and 2 centrals (maxilla). One crown fracture, one retention loss and one endodontic complication were experienced (survival rate: 97.5%). MLD single crowns could be safely indicated on teeth with knife-edge preparations.


Asunto(s)
Porcelana Dental , Diseño de Prótesis Dental , Cerámica , Diseño Asistido por Computadora , Coronas , Humanos , Ensayo de Materiales , Reproducibilidad de los Resultados , Estudios Retrospectivos
3.
Eur Phys J C Part Fields ; 78(6): 505, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30956555

RESUMEN

Inelastic nuclear interaction probability of 400 GeV/c protons interacting with bent silicon crystals was investigated, in particular for both types of crystals installed at the CERN Large Hadron Collider for beam collimation purposes. In comparison to amorphous scattering interaction, in planar channeling this probability is ∼ 36 % for the quasi-mosaic type (planes (111)), and ∼ 27 % for the strip type (planes (110)). Moreover, the absolute inelastic nuclear interaction probability in the axial channeling orientation, along the ⟨ 110 ⟩ axis, was estimated for the first time, finding a value of 0.6 % for a crystal 2 mm long along the beam direction, with a bending angle of 55 µ rad. This value is more than two times lower with respect to the planar channeling orientation of the same crystal, and increases with the vertical angular misalignment. Finally, the correlation between the inelastic nuclear interaction probability in the planar channeling and the silicon crystal curvature is reported.

4.
Leukemia ; 24(8): 1445-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20520635

RESUMEN

Chronic myeloid leukemia (CML) is caused by the BCR-ABL hybrid gene. The molecular mechanisms leading from chronic phase (CP) to blast crisis (BC) are not understood. However, both the presence and the levels of BCR-ABL seem to be important for CML progression. BCR-ABL is under the transcriptional control of BCR promoter. Here we focused on the gene expression control of BCR and BCR-ABL upon myeloid differentiation in healthy donors (HDs), CP and BC patients. As previously reported, BCR-ABL is downregulated during myeloid maturation in CP patients. A similar pattern was detected for BCR (but not for ABL) in CP-CML and in HD, thus suggesting that the two genes may be under a similar transcriptional control. In BC this mechanism is similarly impaired for both BCR-ABL and BCR. These data indicate the presence of an 'in trans' deregulated transcription of both BCR and BCR-ABL promoters, associated with CML progression.


Asunto(s)
Crisis Blástica , Diferenciación Celular , Proteínas de Fusión bcr-abl/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Proteínas Proto-Oncogénicas c-bcr/metabolismo , Secuencia de Bases , Cartilla de ADN , Proteínas de Fusión bcr-abl/genética , Humanos , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-bcr/genética
6.
Brain Res Bull ; 82(1-2): 25-8, 2010 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-20152887

RESUMEN

Autism is a strong genetic disorder, with an estimated heritability greater than 90%. Nonetheless, its specific genetic aetiology remains largely unknown. Autism is associated with epilepsy in early childhood and epilepsy occurs in 10-30% of individuals with autism. Here we report the case of a woman affected by a severe epileptic disorder with an onset at 14 years old. She is affected by a cryptogenetic focal epilepsy with complex partial (psychomotor) and secondarily generalized tonic-clonic seizures, which are drug resistant. The woman is married to a healthy man and has six children: two girls are healthy, a girl and two boys are affected by autism while one boy shows partial seizures. The three children with autism show moderate mental retardation and an EEG with no epileptiform alterations. The child with epileptic seizures shows an asymmetric EEG that is not necessarily pathological. In this family, no chromosomal rearrangements were detected by means of classical cytogenetic analyses. The presence of FRAXA alterations and of microdeletions of the 15q11-q13 chromosome region were also excluded. A genome-wide linkage analysis using microsatellite markers revealed several chromosome regions as possible susceptibility loci.


Asunto(s)
Trastorno Autístico , Epilepsia , Adolescente , Adulto , Edad de Inicio , Trastorno Autístico/genética , Trastorno Autístico/fisiopatología , Niño , Cromosomas Humanos/genética , Electroencefalografía , Epilepsia/genética , Epilepsia/fisiopatología , Femenino , Ligamiento Genético , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Linaje , Embarazo
7.
Oncogene ; 28(15): 1807-11, 2009 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-19287454

RESUMEN

Glioblastomas (GBMs) contain transformed, self-maintaining, multipotent, tumour-initiating cancer stem cells, whose identification has radically changed our perspective on the physiology of these tumours. Currently, it is unknown whether multiple types of transformed precursors, which display alternative sets of the complement of properties of true cancer stem cells, can be found in a GBM. If different subsets of such cancer stem-like cells (CSCs) do exist, they might represent distinct cell targets, with a differential therapeutic importance, also depending on their characteristics and lineage relationship. Here, we report the presence of two types of CSCs within different regions of the same human GBM. Cytogenetic and molecular analysis shows that the two types of CSCs bear quite diverse tumorigenic potential and distinct genetic anomalies, and, yet, derive from common ancestor cells. This provides critical information to unravel the development of CSCs and the key molecular/genetic components underpinning tumorigenicity in human GBMs.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Glioblastoma/genética , Glioblastoma/patología , Células Madre Neoplásicas/patología , Animales , Línea Celular Tumoral , Aberraciones Cromosómicas , Genoma , Humanos , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad
8.
Clin Exp Pharmacol Physiol ; 34(3): 205-9, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17250640

RESUMEN

1. Angiotensin (Ang) II plays a major role in vascular remodelling. Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are involved in the tissue remodelling processes. The aim of the present study was to investigate whether AngII modulates TIMP-2 expression in rat aortic smooth muscle cells in vivo. 2. Angiotensin II (200 ng/kg per min, s.c.) or AngII + losartan (10 mg/kg per day, s.c.) or normal saline was administered continuously by osmotic minipumps to Sprague-Dawley rats for 1 week. In addition, the effect of endogenous AngII on TIMP-2 expression was evaluated in renovascular hypertensive rats (two kidney, one clip (2K1C) and one kidney, one clip (1K1C) models). Control rats (sham 2K1C and sham 1K1C rats) underwent sham-clipping of the left renal artery. At the end of the treatment, plasma renin activity was measured by radioimmunoassay, aortic TIMP-2 mRNA expression was evaluated by real-time polymerase chain reaction and/or northern blotting and protein expression was evaluated by immunohistochemistry. Systolic blood pressure (SBP) was measured twice a week by the tail-cuff method. 3. Exogenous AngII administration produced the expected increase in SBP (P = 0.02) compared with the control saline-treated group. The increase in SBP was abolished in AngII + losartan-treated rats. Administration of AngII caused a significant increase in TIMP-2 expression (P = 0.01) in rat aortic smooth muscle cells that was abolished in AngII + losartan-treated rats. In renovascular hypertensive rats, SBP was higher (P < 0.0001) in 2K1C and 1K1C rats compared with the corresponding sham-operated rats. Plasma renin activity was higher (P < 0.01) in 2K1C rats compared with the other groups. The expression of TIMP-2 was significantly (P < 0.05) increased only in 2K1C rats. 4. Our in vivo data demonstrate that exogenous and endogenous AngII increases TIMP-2 expression in rat aortic smooth muscle cells. This effect is not dependent on the AngII-induced increase in blood pressure and is mediated by angiotensin AT1 receptors.


Asunto(s)
Angiotensina II/farmacología , Presión Sanguínea/fisiología , Músculo Liso Vascular/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/biosíntesis , Animales , Aorta/citología , Aorta/efectos de los fármacos , Aorta/metabolismo , Northern Blotting , Células Cultivadas , Hipertensión Renovascular/patología , Inmunohistoquímica , Masculino , Músculo Liso Vascular/efectos de los fármacos , ARN Mensajero/biosíntesis , ARN Mensajero/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Renina/sangre , Sistema Renina-Angiotensina/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
Pediatr Med Chir ; 25(4): 266-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15070269

RESUMEN

BACKGROUND: Survival of neonates with critical pulmonary obstruction depends on cardiac morphology and function but also on proper perinatal management. METHODS: Postnatal outcome of five neonates with critical pulmonary stenosis or pulmonary atresia detected in utero is reported. RESULTS: Right ventricular morphology and ratio between tricuspid and mitral annulus at Fetal Echocardiography were the most important prognostic parameters. Increasing severity of obstruction and of right ventricular hypoplasia was documented in two fetuses. CONCLUSION: Prenatal diagnosis was useful for planning delivery; we hypothesize that it can be of benefit on postnatal outcome. In selected cases, earlier delivery and relief of obstruction could have beneficial effect on prognosis.


Asunto(s)
Atresia Pulmonar/diagnóstico por imagen , Estenosis de la Válvula Pulmonar/diagnóstico por imagen , Ultrasonografía Prenatal , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Embarazo , Pronóstico
10.
J Oral Rehabil ; 29(11): 1082-90, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12453263

RESUMEN

The aim of this study was to describe the distribution of occlusal contacts in subjects with signs or symptoms of temporomandibular disorder (TMD), and to assess whether any difference exists with healthy subjects. Twenty-five university dental students with complete natural dentition who exhibited TMD (13 females and 12 males, age from 19 to 30 years) and 25 age- and sex-matched controls entered the study. Occlusal contacts were evaluated in the intercuspal position and wax registrations were made in all subjects. Occlusal contacts were classified according to location and intensity. No differences were found between TMD and control groups for the overall number and distribution of contacts or for any side and intensity of contact. An intra-subject analysis showed that TMD subjects had significantly greater bilateral asymmetry in the number of contacts than controls. Median absolute difference of the number of contacts on right and left sides was 3 (95% CI, 2-4) in TMD subjects and 2 (95% CI, 1-2) in controls. In TMD subjects with mono-lateral TMD there was a significant concordance (88.9%) between the side of disorder and the side of higher number of contacts. These findings, while confirming that a significant relationship exists between distribution of occlusal contacts and TMD, further suggest that in young adults it may be primarily expressed by asymmetries in occlusal contact patterns. Existence and aetiology of any association of TMD with occlusal contacts should be further investigated.


Asunto(s)
Oclusión Dental , Trastornos de la Articulación Temporomandibular/etiología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Registro de la Relación Maxilomandibular , Masculino , Maloclusión/complicaciones , Maloclusión/patología , Estadísticas no Paramétricas , Trastornos de la Articulación Temporomandibular/patología
11.
J Interv Cardiol ; 14(3): 319-24, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12053391

RESUMEN

BACKGROUND: The STARFlex (SF) device is a CardioSEAL (CS) double-umbrella device that has been modified by the addition of a self-centering mechanism comprised of nitinol springs connected between the two umbrellas and a flexible core wire with a pin-pivoting connection. This paper compares the results of atrial septal defect (ASD) closure with CardioSEAL and STARFlex devices. PATIENTS AND METHODS: Between December 1996 and March 2000, 117 patients underwent ASD closure with CardioSEAL (n = 79) and STARFlex (n = 38). The mean age (17 years), weight (49 kg), and ASD size (15 mm) were similar in the two groups. The procedures were performed under general anesthesia with both fluoroscopic and transesophageal echocardiographic monitoring. IMMEDIATE RESULTS: The devices were successfully implanted in all patients. Ten patients had multiple ASDs. A single device was used in four patients (CardioSEAL in three, STARFlex in one), while a simultaneous placement of two CardioSEAL (one patient) or two STARFlex (five patients) were performed in six patients. The results are summarized as follows: [table: see text] Follow-Up Results: On follow-up clinical exam, electrocardiograms, chest X-rays, and echocardiograms were obtained at 1, 6, and 12 months. [table: see text] During follow-up there were no deaths, endocarditis, rhythm disturbances, or other complications. Arm fractures were observed almost exclusively with large CardioSEAL devices (40 mm, less frequently with 33 mm), and only in one 33-mm STARFlex device. There were no clinical complications related to fractures. CONCLUSIONS: The STARFlex device seems to offer better results than the CardioSEAL, with significantly lower rates of residual shunts and arm fractures.


Asunto(s)
Cateterismo Cardíaco , Embolización Terapéutica/instrumentación , Defectos del Tabique Interatrial/terapia , Adolescente , Estudios de Seguimiento , Humanos , Resultado del Tratamiento
12.
Artículo en Inglés | MEDLINE | ID: mdl-11101986

RESUMEN

We analyze a time series of velocities of the low-speed stream measured by the Helios spacecraft in the inner heliosphere, which is the region of space dominated by the solar wind flow. We use a nonlinear filter to give a faithful representation of the solar wind nonlinear behavior. We have demonstrated that the influence of noise in the data can be much more efficiently reduced by a nonlinear filter than with the conventional (linear) filters, and this allows a more realistic calculation of the solar wind entropy. The resulting Kolmogorov entropy is positive, and possibly the largest Lyapunov exponent is also positive locally, which would exhibit exponential sensitivity to initial conditions. Thus, these results show that the solar wind in the inner heliosphere is most likely a deterministic chaotic system.

13.
Am J Med Genet ; 90(5): 356-7, 2000 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-10706354

RESUMEN

Isolated right ventricular hypoplasia is a rare congenital anomaly. This condition is usually associated with a communication between the atria in the form of a patent foramen ovale or secondum atrial septal defect. We describe a familial occurrence of this rare disease. A 1-day-old male child and his 34-year-old father were found to have isolated right ventricular hypoplasia with atrial septal defect. An autosomal dominant mode of inheritance is likely for this rare congenital anomaly.


Asunto(s)
Defectos del Tabique Interatrial/genética , Ventrículos Cardíacos/anomalías , Adulto , Humanos , Hibridación Fluorescente in Situ , Recién Nacido , Masculino , Linaje
15.
J Thorac Cardiovasc Surg ; 115(5): 1074-9, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9605077

RESUMEN

OBJECTIVES: To evaluate midterm results of mechanical valves in pulmonary position in patients with pulmonary regurgitation and right ventricular dysfunction as an alternative to bioprostheses. PATIENTS: Mechanical valves (six tilting disc valves and two bileaflet valves) were implanted in eight patients previously operated on for tetralogy of Fallot (n = 7) and truncus arteriosus (n = 1), with severe right ventricular dysfunction caused by massive pulmonary regurgitation. RESULTS: All patients survived prosthesis implantation and are currently well. At follow-up (3 months to 9 years), they do not show signs of valve failure, and right ventricular function has dramatically improved in all but one, who still shows moderate ventricular hypokinesia. CONCLUSION: After operative correction of congenital heart defects in selected patients who show severe dysfunction of the right ventricle caused by pulmonary regurgitation/stenosis, mechanical valves may represent an alternative to bioprosthetic valves. The selection of the valve type is still a matter of debate. However, according to literature data, complications seem to have occurred only in patients with bileaflet mechanical valves in the pulmonary position, whereas no thromboembolic episodes or valve failure is reported in subjects with tilting disc valves in the right ventricular outflow. Tilting disc valves might perform better in the right ventricular outflow than bileaflet valves.


Asunto(s)
Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Pulmonar/cirugía , Disfunción Ventricular Derecha/cirugía , Adolescente , Velocidad del Flujo Sanguíneo , Niño , Ecocardiografía Doppler , Electrocardiografía Ambulatoria , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/cirugía , Humanos , Masculino , Complicaciones Posoperatorias/fisiopatología , Complicaciones Posoperatorias/cirugía , Válvula Pulmonar/diagnóstico por imagen , Válvula Pulmonar/cirugía , Insuficiencia de la Válvula Pulmonar/etiología , Insuficiencia de la Válvula Pulmonar/fisiopatología , Estudios Retrospectivos , Disfunción Ventricular Derecha/etiología , Disfunción Ventricular Derecha/fisiopatología , Presión Ventricular
17.
J Interv Cardiol ; 8(6 Suppl): 759-66, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10159767

RESUMEN

Between February 1988 and September 1993 balloon aortic valvuloplasty was attempted in 33 consecutive patients in the first year of life: 20 patients (61%) were younger than 1 month. Major associated anomalies such as mitral stenosis, coarctation, and hypoplastic left ventricle were found in 11 cases (33%). The balloon dilation of the aortic valve was accomplished through the right carotid cut-down approach in neonates and patients with body weight < 5 kg, through a percutaneous femoral approach in the others; the procedure was completed in all. The peak systolic gradient across the aortic valve measured at catheterization fell from 80 +/- 33 mmHg (range 25-165) before the dilation to 27 +/- 17 mmHg (range 0-65), afterwards (p < 0.0001). The left ventricular ejection fraction increased from 44% +/- 26% to 61% +/- 17%, 24-48 hours after the procedure (p < 0.0001). Aortic insufficiency developed in 17 cases, being moderate in 2, mild in 6, and trivial in 9. Seven patients (21%), all in the first month of life, died within 30 days from the valvuloplasty; major associated anomalies were present in six; the death was due to a procedure related complication in one. No mortality was observed among the patients undergoing valvuloplasty beyond the first month of life. On follow-up (6 months to 6 years) aortic restenosis occurred in 3 cases; 1 was treated by surgical valvotomy, 2 by repeat balloon valvatomy; in another 2 cases, a subvalvular aortic obstruction developed and was relieved by surgical resection. There was no late mortality. Thus, balloon valvuloplasty appears to be an effective palliation for critical aortic stenosis in infancy. Early mortality is mainly related to associated anomalies.


Asunto(s)
Estenosis de la Válvula Aórtica/terapia , Cateterismo/métodos , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/mortalidad , Arterias Carótidas/diagnóstico por imagen , Cateterismo/efectos adversos , Cateterismo/mortalidad , Humanos , Lactante , Recién Nacido , Radiografía , Función Ventricular Izquierda
18.
Cardiologia ; 38(12 Suppl 1): 361-5, 1993 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-8020037

RESUMEN

The aim of this study was to present the experience of 2 Institutions (Department of Cardiology in Bergamo and Department of Pediatric Cardiology, Apuano Pediatric Hospital in Massa) in performing the balloon dilatation of the pulmonary valve. From January 1985 to August 1993 the balloon pulmonary valvuloplasty was performed in 220 patients, age ranging from 1 day to 60 years (mean age 5 years), 55 (25%) in the first year of life, 17 (8%) in the first week of life. The systolic gradient across the pulmonary valve fell from 78 +/- 31 mmHg (range 40-160) to 20 +/- 16 mmHg (range 0-70) immediately after the procedure (p < 0.001). In-hospital mortality happened in 3 cases (1.3%); 2 of them were neonates with critical pulmonary stenosis. In 7 cases (3%) the balloon valvuloplasty was repeated afterwards, because of inadequate relief of the gradient after the first dilatation. During the mean follow-up period of 4 years the other 210 patients (95%) did not need any further treatment and remain in stable clinical conditions. The balloon valvuloplasty gives excellent early and intermediate term results and should be considered the first choice procedure in the treatment of pulmonary stenosis at all ages.


Asunto(s)
Cateterismo , Estenosis de la Válvula Pulmonar/terapia , Adolescente , Adulto , Cateterismo/efectos adversos , Niño , Preescolar , Estudios de Seguimiento , Mortalidad Hospitalaria , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad
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