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1.
Acta Histochem ; 124(3): 151870, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35218995

RESUMEN

Vasa, PIWI and TDRKH are conserved components of germ granules that in metazoans are involved in germline specification and differentiation, as documented by mutational experiments in some model animals. So far, investigations on PIWI during spermatogenesis of fish has been limited to a few species, and no information is available for TDRKH, another protein involved in the piRNA pathway. In this study, the immunolocalization of these three germline determinants was analyzed in male gonads of the teleost fish Poecilia reticulata to document their localization pattern in the different stages of germ cell differentiation. To analyze their distribution pattern during the different stages of spermatogenesis we performed immunohistochemistry (IHC) and immunofluorescence (IF) assays using primary polyclonal antibodies after testing their specificity with Western Blot. Moreover, sections of testis stained with haematoxylin and eosin clarified the structural organization of P. reticulata testis, while the use of the confocal microscope and the nuclear staining clarified the different stages of germ cell differentiation during spermatogenesis. The results showed that Vasa, PIWI and TDRKH were specifically immunolocalized in the germ cells of P. reticulata, with no specific signal detected in Sertoli cells and in other somatic cells of the gonad. These markers were detected in all stages of differentiation from early spermatogonia to advanced spermatids. Vasa staining was the strongest in spermatogonia, and then decreases throughout differentiation. Instead, both PIWI and TDRKH staining increases during differentiation, and their distribution pattern, similar to what observed in the mouse, suggests their concerted participation in the piRNA pathway also in this fish.


Asunto(s)
Poecilia , Animales , Células Germinativas/metabolismo , Gónadas/metabolismo , Masculino , Ratones , Proteínas de Unión al ARN/metabolismo , Espermátides , Espermatogénesis/genética , Testículo/metabolismo
2.
Rev Med Interne ; 40(10): 645-653, 2019 Oct.
Artículo en Francés | MEDLINE | ID: mdl-30885414

RESUMEN

INTRODUCTION: Functional somatic syndromes, grouping somatic symptoms without an organic explanation, are defined either by their predominant symptoms or by an attribution to an, often hypothetical, cause. Due to many similarities, some authors consider that there is only one FSS due to a general phenomenon of "somatization". The objective of this work was to compare two functional somatic syndromes, one defined by its symptoms, fibromyalgia, and the other by a specific contested attribution, electro-hypersensitivity. METHOD: Fibromyalgia or electro-hypersensitive participants (EHS) were recruited from September 2016 to April 2017 through associations of patients in Auvergne-Rhône-Alpes. Home interviews included the collection of medical, psychopathological, and symptom histories. The assessment of psychological distress, quality of life and the search for other functional somatic syndromes was performed through structured questionnaires, self-administrated scales, and clinical examination. RESULTS: Sixteen fibromyalgia subjects and sixteen EHS subjects were included. There are differences in symptomatology, although many symptoms are common to both conditions. Lifetime history of psychiatric disorders and current psychological distress and psychopathology are frequent in both groups but more prevalent in fibromyalgia subjects. The experience of the symptoms, their interpretation, the diagnostic itineraries and the therapeutic behaviours differ radically according to the group, even if for all socio-professional impact is high and quality of life are altered. CONCLUSION: The health status of fibromyalgia persons is overall worse than the health status of electro-hypersensitive individuals in this small sample. Despite the overlap in symptoms and a similar impact on daily functioning, this exploratory study suggests that heterogeneous mechanisms of "somatization" may be at stake in functional somatic syndromes.


Asunto(s)
Radiación Electromagnética , Enfermedades Ambientales/psicología , Fibromialgia/psicología , Trastornos Somatomorfos/psicología , Estrés Psicológico/diagnóstico , Adulto , Anciano , Enfermedades Ambientales/diagnóstico , Enfermedades Ambientales/terapia , Femenino , Fibromialgia/diagnóstico , Fibromialgia/terapia , Estado de Salud , Humanos , Masculino , Anamnesis , Persona de Mediana Edad , Calidad de Vida , Trastornos Somatomorfos/diagnóstico , Trastornos Somatomorfos/terapia , Evaluación de Síntomas , Síndrome
4.
Herz ; 40(4): 600-6, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26077775

RESUMEN

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disease of the heart muscle, mostly due to genetically defective desmosomal proteins. The disease is characterized by fibrofatty replacement leading to ventricular arrhythmias and sudden death in young people and athletes. There is no single clinical gold standard examination for making a definitive diagnosis. The diagnosis is based on multiple parameters, including: (1) global or regional dysfunction and structural alteration of the right ventricle demonstrated on imaging; (2) tissue characterization by endomyocardial biopsy; (3) repolarization and (4) depolarization electrocardiographic abnormalities; (5) arrhythmias; and (6) family history. The so-called phenocopies must be included in the differential diagnosis, always taking into account that there is no single criterion sufficiently specific for a reliable diagnosis of ARVC. Contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) is not yet included in the revised diagnostic criteria, although this is the only imaging modality able to depict fibrosis as late gadolinium enhancement (LGE) deposition. This review analyzes the role of CMR imaging in the diagnostic work-up of ARVC. The lack of specific diagnostic criteria contributes to the under-recognition of the nonclassic variants of ARVC, i.e., dominant or isolated left ventricular disease.


Asunto(s)
Displasia Ventricular Derecha Arritmogénica/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Cinemagnética/métodos , Volumen Sistólico , Disfunción Ventricular Derecha/diagnóstico , Displasia Ventricular Derecha Arritmogénica/complicaciones , Diagnóstico Diferencial , Humanos , Disfunción Ventricular Derecha/etiología
5.
Eur Rev Med Pharmacol Sci ; 18(4): 566-74, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24615182

RESUMEN

Informed consent is part of a process of communication useful to obtain an agreement (conscious, voluntary and free) between doctors and patients. Mesotherapy is based on the introduction of drugs by intradermal route in order to obtain a dose-sparing effect with respect to deeper administration. Opioids are the most appropriate therapy for patients who do not respond to other therapies. Proper communication between doctor and patient, including an explanation of the potential benefits, limitations and risks (even mild), is recommended both in clinical practice and research. Active participation of the patient has the advantage of better control of adverse events, both of mesotherapy and opioid-based therapy. This information-education process returns to the fundamental concept of "first do no harm" and set a "therapeutic partnership" with patients.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Conocimientos, Actitudes y Práctica en Salud , Consentimiento Informado , Mesoterapia , Pacientes/psicología , Actitud del Personal de Salud , Comunicación , Humanos , Mesoterapia/efectos adversos , Educación del Paciente como Asunto , Participación del Paciente , Relaciones Médico-Paciente , Medición de Riesgo , Factores de Riesgo
6.
Rev Sci Instrum ; 85(2): 02B909, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24593614

RESUMEN

Two linear trap devices for particle beam manipulation (including emittance reduction, cooling, control of instabilities, dust dynamics, and non-neutral plasmas) are here presented, namely, a radiofrequency quadrupole (RFQ) beam cooler and a compact Penning trap with a dust injector. Both beam dynamics studies by means of dedicated codes including the interaction of the ions with a buffer gas (up to 3 Pa pressure), and the electromagnetic design of the RFQ beam cooler are reported. The compact multipurpose Penning trap is aimed to the study of multispecies charged particle samples, primarily electron beams interacting with a background gas and/or a micrometric dust contaminant. Using a 0.9 T solenoid and an electrode stack where both static and RF electric fields can be applied, both beam transport and confinement operations will be available. The design of the apparatus is presented.

7.
Curr Med Res Opin ; 30(4): 555-64, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24251879

RESUMEN

BACKGROUND: Opioids may alleviate chronic neuropathic pain (NP), but are considered second/third-line analgesia due to their poor gastrointestinal (GI) tolerability. A fixed combination of prolonged-release oxycodone and naloxone (OXN) has been developed to overcome the GI effects. The aim of this analysis was to evaluate analgesic effectiveness and tolerability of low-dose OXN in patients with moderate-to-severe noncancer NP despite analgesia. METHODS: This retrospective observation of consecutive adult patients, treated open-label for 8 weeks at a single Italian centre, evaluated effectiveness (pain intensity numerical rating scale [NRS], Patients' Global Impression of Change [PGIC], Douleur Neuropathique 4 inventory [DN4] and Chronic Pain Sleep Inventory [CPSI]), doses of daily OXN and adjuvant medication, rescue paracetamol use, bowel function index (BFI), laxative use, and safety. RESULTS: Of 200 patients (mean age 65.9 years; 54% female) with NP included in the analysis; 97% completed 8 weeks' treatment. At the observation start, all patients were taking anticonvulsants and complained of constipation, and 60% were receiving opioids. Pain intensity and DN4 score decreased significantly by endpoint (NRS p < 0.0001; DN4 p < 0.0001) and need for rescue analgesics abated. Reduction in pain intensity throughout the observation was similar regardless of NP aetiology. According to PGIC, 87.8% of patients were much/extremely improved, CPSI (p < 0.0001) and BFI were significantly improved (p < 0.0001) and laxative use decreased. No differences were found between patients <65 years vs those ≥65 years. OXN was generally well tolerated. STUDY LIMITATIONS: Study limitations including the retrospective observational design, the lack of a control group and the single-centre design may limit the generalizability of our findings. CONCLUSIONS: Low-dose OXN (25.0 ± 12.5 mg/day) added to anticonvulsants was highly effective in controlling noncancer NP of varied aetiology, with reduced need for rescue analgesia and improved quality of sleep, and was well tolerated, with improved bowel function and reduced laxative use. The efficacy and tolerability of OXN demonstrated in this real-world setting suggest its utility in this difficult to manage patient population.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Naloxona/administración & dosificación , Neuralgia/tratamiento farmacológico , Oxicodona/administración & dosificación , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/efectos adversos , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Naloxona/efectos adversos , Oxicodona/efectos adversos , Estudios Retrospectivos
9.
Hematology ; 17 Suppl 1: S150-2, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22507806

RESUMEN

The von Willebrand factor (VWF) is analysed as a bleeding and thrombotic risk marker. When the VWF level is increased, it predicts a thrombotic phenotype and when VWF level is low in plasma, the phenotype varies to bleeding disorder. But it is quite challenging to define when the level is low, normal or high taking into account that these values are capricious and overlap. This matter should be solved by extensive epidemiologic studies. VWD is a hereditary disorder with several described mutations. VWF is a major acute-phase reactant, besides the physiological conditions such as blood group and pregnancy that affect plasmatic VWF levels. Subjects with O blood group have 25% less VWF than those of non O blood groups, and the latter show higher thrombus burden. VWF would be sensitive though not specific diagnostic marker of myocardial infarction. For the assessment of bleeding severity there are special surveys, scores and pictorial charts. The identification of VWF as a thrombotic risk marker has not been clearly established yet, but it has been involved in stroke and coronary disease. We only have the specific replacement therapy for the bleeding phenotype and we can speculate that enoxaparin and PEG-hirudin are able to blunt the VWF rise in patients with unstable angina pectoris and it is associated with a more favourable clinical outcome. Only two questions remain: does VWF as a bleeding risk marker have the same value as a thrombotic risk marker? Will successful treatments like those achieved for bleeding be also possible in the future for thrombosis?


Asunto(s)
Hemorragia/diagnóstico , Trombosis/diagnóstico , Factor de von Willebrand , Hemorragia/etiología , Humanos , Factores de Riesgo , Trombosis/etiología
10.
Haemophilia ; 18(1): 112-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21592258

RESUMEN

Most mutations identified in 2A VWD patients are localized in the A2 domain, although missense substitutions have also been recognized in the A1 domain. We describe a novel heterozygous missense mutation in the A1 domain of VWF gene responsible for type 2A phenotype. Analysis of the complete exon 28 was carried out in a patient and his mother with life-long histories of moderate to severe bleeding and laboratory data of type 2A VWD. The analysis of exon 28 of VWF gene showed a 3815 G → T transversion resulting in C1272F mutation. It is probably associated with a group I mechanism according to patients' clinical symptoms, and, in the case of the propositus, the lack of clinical response to treatment with desmopressin. The mutation was not found in 100 normal alleles. This substitution affected the normal S-S bound between C1272 and C1458, which is involved in A1 loop structure, altering the normal multimerization and function of VWF. The VWFpp/VWF:Ag ratio in the propositus and his mother was >3, suggesting a shortened survival of VWF. We believe it is important to report the complete clinical phenotype corresponding to the new mutation to increase the knowledge in the clinical field.


Asunto(s)
Mutación Missense , Enfermedad de von Willebrand Tipo 2/genética , Factor de von Willebrand/genética , Adolescente , Adulto , Desamino Arginina Vasopresina/uso terapéutico , Exones/genética , Femenino , Hemostáticos/uso terapéutico , Humanos , Masculino , Fenotipo , Enfermedad de von Willebrand Tipo 2/tratamiento farmacológico
11.
Haemophilia ; 16 Suppl 5: 67-73, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20590859

RESUMEN

SUMMARY: In this paper, the recent developments in the diagnosis and laboratory issues of von Willebrand's disease (VWD) are presented. Dr. Castaman reviews the functional tests available for the diagnosis of VWD and their pathophysiological significance, focusing on which tests are best used in the diagnosis and classification of VWD. Dr Montgomery reviews an emerging issue that is accelerated clearance of von Willebrand factor (VWF) occurring in some variants of VWD. This phenotype can be suspected by the presence of an increased ratio between the VWF propeptide and the VWF antigen. These patients have typically a robust, but short-lived increase of FVIII and VWF after desmopressin. Dr Meschengieser reviews the determinants of bleeding after surgery in patients with VWD, emphasizing the role of bleeding history in predicting this risk.


Asunto(s)
Pruebas de Coagulación Sanguínea/métodos , Enfermedades de von Willebrand/diagnóstico , Factor de von Willebrand/análisis , Biomarcadores/análisis , Técnicas de Laboratorio Clínico , Ensayo de Inmunoadsorción Enzimática , Humanos , Hemorragia Posoperatoria , Valor Predictivo de las Pruebas , Factores de Riesgo , Enfermedades de von Willebrand/clasificación , Factor de von Willebrand/metabolismo
12.
Curr Med Res Opin ; 21(7): 1085-90, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16004677

RESUMEN

OBJECTIVE: Anticoagulation clinics have improved the time spent within therapeutic range and decreased hemorrhagic complications and costs in chronic oral anticoagulation. Whether these benefits correlate to patients' quality of life (QOL) remains to be determined. The impact of patients' perceptions about anticoagulation on QOL has not been evaluated. The objective of this study was to evaluate prospectively patients' perceptions and quality of life in patients chronically anticoagulated. RESEARCH DESIGN AND METHODS: A cross-sectional study was designed to investigate the prevalence of positive and negative perceptions about oral anticoagulation therapy (OAT) and to identify vulnerable groups. Patients anonymously completed the SF-36 survey and a questionnaire that focused on patients' perceptions of protection from thrombotic complications or fear of haemorrhage due to the anticoagulation. We related those perceptions to the General Health SF-36 score, to the patient's characteristics, the absolute bleeding risk (i.e. intended International Normalized Ratio [INR]), duration of therapy and medical attention. RESULTS: One thousand patients were included and 905 questionnaires evaluated. Most patients felt protected and better since the beginning of therapy (71.5% and 61.5%, respectively). Patient characteristics associated with negative perceptions were; female sex (Odds Ratio [OR] 1.58, 95% Confidence Interval [CI] 1.06-2.36, p = 0.01); patients with less than 1 year of therapy (OR 2.16, 95% CI 1.34-3.48, p = 0.006); those not satisfied with medical attention (OR 2.86, 95% CI 1.53-5.18, p = 0.0001); and those that modified their lifestyle (OR 2.75, 95% CI 1.49-4.91, p = 0.0002). Patients with a lower bleeding risk (INR 2.0-3.0) had more negative perceptions than those with a higher risk. Patients with negative perceptions achieved the lowest score in the SF-36 survey. Haemorrhages did not affect patients' perception or QOL. CONCLUSIONS: Patients' perceptions correlated with QOL. We were able to identify patient characteristics associated with poor QOL and thus the group of patients whose negative perceptions most warranted special attention from their clinicians.


Asunto(s)
Anticoagulantes/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Satisfacción del Paciente , Calidad de Vida , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Enfermedades Cardiovasculares/complicaciones , Niño , Estudios Transversales , Femenino , Hemorragia/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Percepción , Calidad de la Atención de Salud , Encuestas y Cuestionarios , Trombosis/complicaciones
13.
Haemophilia ; 10 Suppl 4: 164-8, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15479392

RESUMEN

von Willebrand disease is the most common inherited bleeding disorder in humans. VWD can be classified into three major types, designated Types 1, 2 and 3; Type 2 can be further separated into subtypes 2A, 2B, 2M and 2N. The diagnosis of VWD requires a personal and family history of bleeding and confirmation by laboratory analysis. Although Types 2 and 3 are relatively straightforward to diagnose, there may be a risk of overdiagnosis of Type 1 because of an overlap within the normal range. We also report on the clinical profile and diagnosis of VWD in a South American cohort of patients and on the in vitro characteristics of some factor concentrates available for treatment of VWD.


Asunto(s)
Enfermedades de von Willebrand/diagnóstico , Adolescente , Adulto , Plaquetas/química , Estudios de Cohortes , Factor VIII/análisis , Factor VIII/uso terapéutico , Salud de la Familia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Complicaciones Hematológicas del Embarazo/sangre , Factores de Riesgo , Enfermedades de von Willebrand/tratamiento farmacológico , Enfermedades de von Willebrand/genética , Factor de von Willebrand/análisis
15.
Blood ; 98(12): 3383-9, 2001 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11719378

RESUMEN

Complement-dependent cytotoxicity is thought to be an important mechanism of action of the anti-CD20 monoclonal antibody rituximab. This study investigates the sensitivity of freshly isolated cells obtained from 33 patients with B-cell chronic lymphocytic leukemia (B-CLL), 5 patients with prolymphocytic leukemia (PLL), and 6 patients with mantle cell lymphoma (MCL) to be lysed by rituximab and complement in vitro. The results showed that in B-CLL and PLL, the levels of CD20, measured by standard immunofluorescence or using calibrated beads, correlated linearly with the lytic response (coefficient greater than or equal to 0.9; P <.0001). Furthermore, the correlation remained highly significant when the 6 patients with MCL were included in the analysis (coefficient 0.91; P <.0001), which suggests that CD20 levels primarily determine lysis regardless of diagnostic group. The role of the complement inhibitors CD46, CD55, and CD59 was also investigated. All B-CLL and PLL cells expressed these molecules, but at different levels. CD46 was relatively weak on all samples (mean fluorescence intensity less than 100), whereas CD55 and CD59 showed variability of expression (mean fluorescence intensity 20-1200 and 20-250, respectively). Although CD55 and CD59 levels did not permit prediction of complement susceptibility, the functional block of these inhibitors demonstrated that they play an important role in regulating complement-dependent cytotoxicity. Thus, lysis of poorly responding B-CLL samples was increased 5- to 6-fold after blocking both CD55 and CD59, whereas that of high responders was essentially complete in the presence of a single blocking antibody. These data demonstrate that CD20, CD55, and CD59 are important factors determining the in vitro response to rituximab and complement and indicate potential strategies to improve the clinical response to this biologic therapy.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antígenos CD20/análisis , Antígenos CD55/inmunología , Antígenos CD59/inmunología , Proteínas del Sistema Complemento/inmunología , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/terapia , Anticuerpos Monoclonales de Origen Murino , Antineoplásicos/uso terapéutico , Antígenos CD55/análisis , Antígenos CD59/análisis , Muerte Celular , Complemento C3/análisis , Complemento C9/análisis , Citotoxicidad Inmunológica , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Humanos , Leucemia Prolinfocítica/inmunología , Rituximab , Linfocitos T/inmunología
17.
Int J Cancer ; 95(6): 364-9, 2001 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-11668518

RESUMEN

Transitional cell carcinoma (TCC) is the most common bladder tumor. Urine cytology can identify most high-grade tumors but sensitivity is lower if one includes lesions of all grades. Microsatellite marker alterations have been found in many tumor types including bladder cancer and have been used to detect cancer cells in body fluids including urine. The aim of our study is to further evaluate feasibility and sensitivity of microsatellite analysis to detect bladder cancer cells in urine. We studied 55 individuals: 21 with symptoms suggestive of bladder cancer, 23 patients with previous history of TCC and 11 healthy subjects. Genomic DNA was extracted from blood lymphocytes, urine sediment, bladder washings and tumor or normal bladder mucosa. Twenty highly informative microsatellite markers were analyzed for loss of heterozigosity (LOH) and microsatellite instability (MIN) by polymerase chain reaction. Microsatellite analysis of urine identified 33 of 34 (97%) patients with either primary or tumor recurrence, whereas urine cytology identified 27 of 34 (79%) patients (p = 0.0001). Detection of microsatellite abnormalities improved the sensitivity of detecting low-grade and/or stage bladder tumor: from 75-95% for grades G1-G2 and from 75-100% for pTis-pTa tumors. Bladder washings from 25 patients were also analyzed, and in all cases results were identical to those obtained from voided urine. None of the 16 patients without evidence of TCC showed LOH and/or MIN in urine samples or bladder washings. Interestingly, in a patient with persistent bladder mucosa abnormalities, microsatellite alterations were demonstrated 8 months before the histopathologic diagnosis of tumor recurrence. These results further indicate that microsatellite marker analysis is more sensitive than conventional urine cytology in detecting bladder cancer cells in urine and represents a potential clinical tool for monitoring patients with low-grade/stage TCC.


Asunto(s)
Carcinoma de Células Transicionales/diagnóstico , Carcinoma de Células Transicionales/orina , Repeticiones de Microsatélite/genética , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/orina , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/genética , Femenino , Humanos , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Tinción con Nitrato de Plata , Expansión de Repetición de Trinucleótido , Neoplasias de la Vejiga Urinaria/genética
18.
Int J Cancer ; 95(6): 378-83, 2001 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-11668521

RESUMEN

Osteochondromas represent the largest group of benign tumors of bone. Multiple osteochondromatosis or hereditary multiple exostoses (EXT) is an autosomal dominant inherited disorder characterized by the presence of multiple benign cartilage-capped exostoses. EXT is genetically heterogeneous with at least 3 chromosomal loci: EXT1 (8q24.1), EXT2 (11p11-p13), and EXT3 (19p). In <5% of EXT patients, the inactivation of both copies of EXT alleles (LOH) is associated with malignant transformation. We have analyzed the EXT1 and EXT2 genes in 9 unrelated EXT families and in a patient with a sporadic osteochondroma, all originating from Italy. Four families show an EXT1 mutation, consisting of a small deletion in 3 of them and a small insertion in the 4th. All these mutations lead to premature termination of translation and thus a truncated EXT1 protein. Three families presented EXT2 mutations consisting of nucleotide substitutions leading to alterations of the third intron splice-site, to an amino acid substitution and to a nonsense mutation. All these mutations cosegregate with the disease phenotype. The sporadic osteochondroma patient carried a novel missense mutation in exon 11 of EXT2 gene, leading to an amino acid substitution. Seven of these mutations have never been described before. EXT2 missense mutations were also confirmed by amino acids conservation between human and mouse and by analysis of a healthy control population. In conclusion, our study provide further evidence that loss of function of the EXT1 or EXT2 gene is the main cause of EXT supporting the putative tumor-suppressor function of these genes.


Asunto(s)
Neoplasias Óseas/diagnóstico , Neoplasias Óseas/genética , N-Acetilglucosaminiltransferasas/genética , Osteocondroma/diagnóstico , Osteocondroma/genética , Proteínas/genética , Adolescente , Adulto , Edad de Inicio , Anciano , Alelos , Secuencia de Bases , Neoplasias Óseas/metabolismo , Niño , Preescolar , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Genes Dominantes , Humanos , Lactante , Italia , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Mutación , Mutación Missense , Osteocondroma/metabolismo , Linaje , Polimorfismo Conformacional Retorcido-Simple
19.
Blood Coagul Fibrinolysis ; 12(3): 207-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11414635

RESUMEN

Haemoperitoneum secondary to haemorrhagic corpus luteum has been described in severe bleeding disorders such as afibrinogenaemia, type 3 von Willebrand's disease and patients under oral anticoagulation. We have studied one patient who presented three episodes of severe bleeding at ovulation, requiring surgery twice, with the diagnosis of mild von Willebrand's disease and mild storage pool deficiency. Mild von Willebrand's disease (associated with other thrombopathies or coagulopathies) should be considered in this pathology, although physicians would prefer to find a severe haemorrhagic disorder as the underlying condition in these cases.


Asunto(s)
Cuerpo Lúteo/irrigación sanguínea , Hemoperitoneo/etiología , Ovulación , Deficiencia de Almacenamiento del Pool Plaquetario/complicaciones , Enfermedades de von Willebrand/complicaciones , Abdomen Agudo/etiología , Adulto , Pruebas de Coagulación Sanguínea , Epistaxis/etiología , Femenino , Hemorragia Gingival/etiología , Hematoma/etiología , Hemoperitoneo/cirugía , Humanos , Recurrencia , Choque/etiología
20.
J Lab Clin Med ; 137(4): 261-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11283520

RESUMEN

The present study investigated the effect of nitric oxide (NO) on megakaryocyte (Mk) proliferation induced by thrombopoietin (TPO). Low-density mononuclear cells (MNCs) and CD34+ cells from human bone marrow (BM) were cultured in liquid medium in the presence of sodium nitroprusside (SNP) or (Z)-1-[2-(aminoethyl)-N-(2-ammonioethyl) amino] diazen-1-ium-1, 2-diolate (DETA/NO) and then stimulated with TPO. Mk number decreased in both NO donors, as identified by flow cytometry 11 to 13 days after TPO stimulation. Nitrite, cyanide, or the carrier molecule DETA failed to reproduce the inhibition caused by NO donors. When CD34+ cells were treated with DETA/NO, the inhibition of Mk growth was even more pronounced than that in MNCs. Failure of the guanosine 3',5'-cyclic monophosphate (cGMP) analog 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP) to inhibit Mk proliferation suggests that cGMP is not involved in Mk suppression mediated by NO. On the other hand, DNA analysis by flow cytometry showed that apoptosis of CD34+ cells and Mks seemed to be at least one of the mechanisms associated with the cytotoxic DETA/NO effect. Stimulation of MNCs or CD34+ cells with tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) increased endogenous NO levels and suppressed Mk growth. Treatment with NO synthesis inhibitors such as L -N(G)-monomethyl arginine (L -NMMA) or L -N(G)-nitroarginine methyl ester hydrochloride (L -NAME) partially reversed Mk growth inhibition induced by TNF-alpha and IFN-gamma, although increased NO levels returned to normal values. The results presented here strongly indicate that NO regulates the growth of Mks induced by TPO by a direct effect on both progenitors and mature Mks.


Asunto(s)
División Celular/fisiología , Megacariocitos/citología , Óxido Nítrico/fisiología , Trombopoyetina/farmacología , Antígenos CD34/inmunología , Apoptosis/fisiología , División Celular/efectos de los fármacos , Citometría de Flujo , Humanos , Megacariocitos/inmunología
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