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1.
Haemophilia ; 29(2): 572-577, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36585888

RESUMEN

INTRODUCTION: Intracerebral hemorrhage (ICH) is associated with high morbidity and mortality in patients with congenital afibrinogenaemia. Details on location of cerebral haemorrhage, management and neurological outcomes are lacking. METHODS: We performed a retrospective study on Egyptian children with congenital afibrinogenaemia who experienced ICH, in order to estimate frequency, symptoms and neurological outcomes. RESULTS: Among 58 children with congenital afibrinogenaemia treated on demand, 18 (31%) had an history of ICH (28 episodes). The first ICH occurred at a median age of 1 year (Q1-Q3 1-7 years). Impaired consciousness level, vomiting and seizures were the most common presenting symptoms. Spontaneous bleeding was associated with a more severe clinical presentation and worse neurological outcomes, including hydrocephaly and impaired cognitive development. Only half of ICH events (n = 14) were treated in less than 24 h from the onset of symptoms. Fibrinogen replacement by Fresh Frozen Plasma (FFP), cryoprecipitate or fibrinogen concentrates was administered in seven (25%), 19 (68%) and three (10%) ICH events, respectively. Overall, seven (25%) ICH occurring in four patients required a surgical intervention. After the ICH, six patients started secondary prophylaxis. The cumulative incidence of ICH at 10 years was 35% (95% CI 23-51) and at 20 years was 40% (95 CI% 26.7-58.8). CONCLUSION: In our cohort of children with congenital afibrinogenaemia, ICH was very frequent and associated with adverse neurological outcomes and death. Further studies are required to determine whether primary prophylaxis starting early in childhood is indicated after diagnosis.


Asunto(s)
Afibrinogenemia , Hemostáticos , Humanos , Niño , Lactante , Incidencia , Estudios Retrospectivos , Afibrinogenemia/complicaciones , Afibrinogenemia/epidemiología , Egipto/epidemiología , Hemorragias Intracraneales/terapia , Hemorragia Cerebral , Hemostáticos/uso terapéutico , Fibrinógeno/uso terapéutico
2.
Rev Epidemiol Sante Publique ; 69(4): 183-192, 2021 Aug.
Artículo en Francés | MEDLINE | ID: mdl-34215480

RESUMEN

BACKGROUND: The professional identities, profiles and representations of Burundian health workers remain insufficiently explored. Our twofold objective is to identify the different socio-professional profiles of first-line caregivers and to explore their respective representations of health workers and work. METHODS: The first study describes the overall population of the 1047 staff members employed in 2014-2015 in 62 health centers. The second is a cross-sectional survey conducted in April 2014. Using IRAMUTEQ© software, we conducted textology analysis of the structure and contents of 911 respondents' representations via 3 free associations with regard to 6 questions on the "good worker" and the "what renders one capable of doing good work". RESULTS: At the normative level, among all categories of staff, a relational role is a foundation of professional identity, while technical or administrative functions remain marginal. At the positional level, responses differed according to initial qualification level but not as a function of their role with patients or their professional experience. Three socio-professional categories emerged. The most qualified category (one-quarter of the population) consists primarily of male caregivers, with a high turnover rate (4 years) associated with prospects for further training and career development. These persons present the most professionalized representations of the worker and work. The second quarter has an average level of qualification and turnover (10 years), and is mainly composed of female caregivers with limited professional perspectives. This group's representations are less technical and more patient-centered. Finally, the remaining half consists of relatively low-skilled staff members in charge of technical and logistical support, who are likely to spend their entire career in the same center (>20 years). Largely disregarded by the health care system and its funders, they have few opportunities for training or advancement and despite their long experience, maintain profane representations of workers and work. CONCLUSION: Our results shed light on the predicament of unskilled staff members whose expectations are rarely taken into consideration, even though they represent a significant proportion of the workforce, perform tasks essential to quality of care, and serve as bearers of the memory of their hospital center. These results also highlight the compartmentalization of practices and knowledge between categories of workers and underscore the failure of continuous training strategies targeting the unskilled.


Asunto(s)
Cuidadores , Burundi , Estudios Transversales , Femenino , Humanos , Masculino , Recursos Humanos
3.
Sci Rep ; 9(1): 7492, 2019 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-31097741

RESUMEN

Subjects increasing sperm DNA fragmentation (sDF) during Density Gradient Centrifugation (DGC), a common sperm selection procedure in Assisted Reproduction Techniques (ARTs), experience a 50% lower probability of pregnancy. Hence, identification of these subjects is of clinical importance. Here, we investigated whether such subjects are identified with higher accuracy detecting DNA fragmentation in viable (viable sDF) instead of total spermatozoa (total sDF) and whether swim up, an alternative procedure to DGC, does not increase sDF. With DGC, we identified 10/20 subjects increasing total sDF, and 2 more subjects using viable sDF. With swim up, we identified 8/40 subjects increasing total sDF, and 8 more subjects using viable sDF. In addition, viable sDF reveals more accurately the increase of the damage when it occurs. Finally, a multivariate analysis demonstrated that the proportional increase of sDF was higher after DGC respect to swim up. In conclusion, viable sDF is a more accurate parameter to reveal the increase of the damage by selection both with swim up and DGC. Swim up increases sDF in some samples, although at a lesser extent than DGC, suggesting that it should be used to select spermatozoa for ARTs when possible.


Asunto(s)
Fragmentación del ADN , Análisis de Semen/métodos , Adulto , Separación Celular/métodos , Centrifugación/métodos , Humanos , Persona de Mediana Edad , Análisis de Semen/normas , Sensibilidad y Especificidad
4.
Nutr Metab Cardiovasc Dis ; 29(6): 604-610, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30952572

RESUMEN

AIM: To evaluate the possible association between dietary habits and progenitor cells using data obtained from a randomized crossover trial using two different diets, lacto-ovo-vegetarian (VD) and Mediterranean (MD), the CARDIVEG study. METHODS AND RESULTS: Eighty clinically healthy subjects with a low-to-moderate cardiovascular risk profile (61 F; 19 M; mean age: 50.7 ± 11.6 years) were randomly assigned to isocaloric VD and MD diets lasting three months each, and then crossed. The two diets showed no effects on endothelial progenitor cells and circulating endothelial cells but opposite effects on circulating progenitor cells. In fact, VD determined significant (p < 0.05) and negative changes on circulating progenitor cells, with an average geometric variation of -130 cells/106 events for CD34+/CD45-/dim, -80 cells/106 events for CD133+/CD45-/dim, and -84 cells/106 events for CD34+/CD133+/CD45-/dim while MD determined significant (p < 0.05) and positive changes for CD34+/CD45-/dim levels, with a geometric mean increase of +54 cells/106 events. No significant correlations were observed between changes in progenitor cells and changes in inflammatory parameters during the VD phase. On the other hand, during the MD phase negative correlations between changes of CD34+/CD45-/dim and interleukin-6 (R = -0.324; p = 0.004) as well as interleukin-8 (R = -0.228; p = 0.04) and monocyte chemotactic protein-1 (R = -0.277; p = 0.01), were observed. These correlations remained significant also after adjustment for confounding factors only for CD34+/CD45-/dim and interleukin-6 (ß = -0.282; p = 0.018) and monocyte chemotactic protein-1 (ß = -0.254; p = 0.031). CONCLUSIONS: MD, but not VD, reported a significant and positive effect on circulating progenitor cells in a group of subjects at low-to-moderate cardiovascular risk, probably acting through the modulation of inflammatory parameters.


Asunto(s)
Antígenos CD/sangre , Enfermedades Cardiovasculares/prevención & control , Dieta Saludable , Dieta Mediterránea , Dieta Vegetariana , Mediadores de Inflamación/sangre , Prevención Primaria/métodos , Células Madre/metabolismo , Antígeno AC133/sangre , Adulto , Anciano , Antígenos CD34/sangre , Biomarcadores/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/inmunología , Quimiocina CCL2/sangre , Estudios Cruzados , Femenino , Humanos , Interleucina-6/sangre , Interleucina-8/sangre , Antígenos Comunes de Leucocito/sangre , Masculino , Persona de Mediana Edad , Fenotipo , Factores Protectores , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Adulto Joven
5.
J Control Release ; 296: 250-257, 2019 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-30682444

RESUMEN

Rho kinase activity in hepatic stellate cells (HSCs) is associated with activation, transformation and contraction of these cells, leading to extracellular matrix production and portal hypertension in liver cirrhosis. Inhibition of rho kinase activity can reduce these activities, but may also lead to side effects, for instance systemic hypotension. This can be circumvented by liver-specific delivery of a rho kinase inhibitor to effector cells. Therefore, we targeted the rho kinase inhibitor Y27632 to the key pathogenic cells in liver fibrosis, i.e. myofibroblasts including activated HSCs that highly express the PDGFß-receptor, using the drug carrier pPB-MSA. This carrier consists of mouse serum albumin (MSA) covalently coupled to several PDGFßR-recognizing moieties (pPB). We aimed to create a prolonged release system of such a targeted construct, by encapsulating pPB-MSA-Y27632 in biodegradable polymeric microspheres, thereby reducing short-lasting peak concentrations and the need for frequent administrations. Firstly, we confirmed the vasodilating potency of PDGFß-receptor targeted Y27632 in vitro in a contraction assay using HSCs seeded on a collagen gel. We subsequently demonstrated the in vivo antifibrotic efficacy of pPB-MSA-Y27632-loaded microspheres in the Mdr2-/- mouse model of progressive biliary liver fibrosis. A single subcutaneous microsphere administration followed by organ harvest one week later clearly attenuated liver fibrosis progression and significantly suppressed the expression of fibrosis related genes, such as several collagens, profibrotic cytokines and matrix metalloproteinases. In conclusion, we demonstrate that polymeric microspheres are suitable as drug delivery system for the sustained systemic delivery of targeted protein constructs with antifibrotic potential, such as pPB-MSA-Y27632. This formulation appears suitable for the sustained treatment of liver fibrosis and possibly other chronic diseases.


Asunto(s)
Amidas/administración & dosificación , Portadores de Fármacos/administración & dosificación , Cirrosis Hepática/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Piridinas/administración & dosificación , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Quinasas Asociadas a rho/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Animales , Línea Celular , Preparaciones de Acción Retardada/administración & dosificación , Femenino , Humanos , Cirrosis Hepática/metabolismo , Ratones Noqueados , Microesferas , Miembro 4 de la Subfamilia B de Casete de Unión a ATP
6.
Br J Nutr ; 121(7): 756-762, 2019 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-30585554

RESUMEN

Previous studies have suggested that vegetarianism can result in a reduction of vitamin B12 circulating levels. The aim of the present study was to investigate the effects of a 3-month dietary intervention with a lacto-ovo-vegetarian diet (VD) on the levels of circulating vitamin B12 in a group of omnivores. We analysed fifty-four omnivorous subjects who followed a VD as a first dietary intervention within the CARDIVEG (Cardiovascular Prevention with Vegetarian Diet) study, a dietary intervention study. VD resulted in a significant reduction (P<0·001) of 51·2 % of vitamin B12 intake and in a significant reduction (P=0·005) of 6·2 % of the circulating levels of vitamin B12 (-24·5 pg/ml). Changes in vitamin B12 intake were significantly correlated with changes in circulating levels of vitamin B12 (R 0·61, P<0·001). Subgroup analyses showed that reduction in circulating vitamin B12 levels was more evident in participants who were younger, overweight, non-smokers and had hypercholesterolaemia. A logistic regression analysis showed that a reduction in vitamin B12 intake greater than the first quartile of the delta changes obtained in the study population (-28·5 %) conferred a significantly higher risk of experiencing a decrease in circulating vitamin B12 levels (OR 10·1; 95 % CI 1·3, 76·1). In conclusion, a 3-month VD period determined a significant reduction in circulating levels of vitamin B12, being significantly correlated with the reduction in vitamin B12 intake. Although a well-planned VD can provide adequate nutrition across all life stages, special care must be taken to ensure adequate vitamin B12 intake and to help prevent deficiency.

8.
Clin Exp Allergy ; 48(7): 825-836, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29700872

RESUMEN

BACKGROUND: Oral immunotherapy (OIT) successfully desensitizes patients with food allergies, but the immune mechanisms mediating its efficacy remain obscure. OBJECTIVES: We tested the hypothesis that allergen-specific regulatory T (Treg) cell function is impaired in food allergy and is restored by anti-IgE antibody (omalizumab)-supplemented OIT. METHODS: Peanut-specific T effector (Teff) and Treg cell proliferative responses, activation markers and cytokine expression were analysed by flow cytometry in 13 peanut-allergic subjects before the start of omalizumab-supplemented OIT and periodically in some subjects thereafter for up to 2 years. Peripheral blood regulatory T cells (Treg cells) were analysed for their peanut-specific suppressor function before and at 1 year following OIT. This study was registered on ClinicalTrials.gov (NCT01290913). RESULTS: Proliferation of allergen-specific Teff and Treg cells precipitously declined following the initiation of omalizumab therapy prior to OIT, followed by partial recovery after the initiation of OIT. At baseline, peanut-specific Treg cells exhibited a Th2 cell-like phenotype, characterized by increased IL-4 expression, which progressively reversed upon OIT. Peanut-specific Treg cell suppressor activity was absent at the start of omalizumab/OIT therapy but became robust following OIT. Absent peanut-specific Treg cell function could also be recovered by the acute blockade of IL-4/IL-4R receptor signalling in Treg cells, which inhibited their IL-4 production. CONCLUSIONS AND CLINICAL RELEVANCE: OIT supplemented by omalizumab promotes allergen desensitization through an initial omalizumab-dependent step that acutely depletes allergen-reactive T cells, followed by an increase in allergen-specific Treg cell activity due to the reversal of their Th2 cell-like programme. Improved Treg cell function may be a key mechanism by which OIT ameliorates food allergy.


Asunto(s)
Antialérgicos/administración & dosificación , Omalizumab/administración & dosificación , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Células Th2/efectos de los fármacos , Células Th2/inmunología , Administración Oral , Alérgenos/inmunología , Biomarcadores , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Islas de CpG , Citocinas/metabolismo , Metilación de ADN , Desensibilización Inmunológica , Epigénesis Genética , Humanos , Inmunización , Memoria Inmunológica , Inmunofenotipificación , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Fenotipo , Transducción de Señal , Linfocitos T Reguladores/metabolismo , Células Th2/metabolismo
9.
Allergol Immunopathol (Madr) ; 46(5): 447-453, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29456038

RESUMEN

BACKGROUND: Transplantation-acquired food allergies (TAFA) are frequently reported and considered to be caused by immunosuppressive therapy. The aim of this study was to investigate the allergic and immunologic responses in children who had liver or kidney transplantations. METHODS: Twelve children receiving liver transplantations and 10 children receiving kidney transplantations were investigated. All children underwent the allergy work-up and in most of them, lymphocyte screening and serum cytokine measurements were also performed. RESULTS: TAFA were found in 7/12 (58%) children with liver transplantations and in none of the 10 children with kidney transplantations. The mean age at transplantation was significantly lower in children who underwent liver transplantations (p<0.001). The immunosuppressive therapy administered to children with liver transplantation was tacrolimus in 11 patients and cyclosporine in one patient, while all 10 children with kidney transplantation received tacrolimus plus mycophenolate. The most common antigenic food was egg. The natural killer (NK) cell numbers were significantly higher in liver-transplant children than in kidney-transplant children. No significant differences were found in the serum cytokine levels. CONCLUSIONS: This study confirms that liver-transplant children treated with tacrolimus alone have a higher risk of developing TAFA than kidney-transplant children treated with tacrolimus plus mycophenolate. NK cells might be involved in this difference.


Asunto(s)
Hipersensibilidad a los Alimentos/inmunología , Huésped Inmunocomprometido/inmunología , Terapia de Inmunosupresión/efectos adversos , Células Asesinas Naturales/inmunología , Trasplante de Hígado , Niño , Preescolar , Femenino , Humanos , Terapia de Inmunosupresión/métodos , Inmunosupresores/efectos adversos , Lactante , Masculino , Ácido Micofenólico/efectos adversos , Tacrolimus/efectos adversos
10.
Int J Hyperthermia ; 34(5): 617-623, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29357717

RESUMEN

CONTEXT: No defined pre-treatment factors are able to predict the response to radiofrequency ablation (RFA) of an autonomously functioning thyroid nodule (AFTN). OBJECTIVE: Primary endpoint was to evaluate the success rate of RFA to restore euthyroidism in a cohort of adult patients with small solitary AFTN compared with medium-sized nodules. Secondary endpoints included nodule volume reduction and rate of conversion from hot nodules to cold using scintiscan. METHODS: This was a 24-month prospective monocentric open parallel-group trial. Twenty-nine patients with AFTN were divided into two groups based on thyroid volume: 15 patients with small nodules (<12 mL) in group A and 14 patients with medium nodules (>12 mL) in group B. All patients underwent a single session of RFA and were clinically, biochemically, and morphologically evaluated at baseline and at 1, 6, 12 and 24 months after treatment. RESULTS: After RFA, there was greater nodule volume reduction in group A compared with group B (p < 0.001 for each follow-up point). In group A, there was a greater increase in TSH levels than in group B at 6 (p = 0.01), 12 (p = 0.005), and 24 months (p < 0.001). At 24 months, the rate of responders was greater in group A than in group B (86 vs. 45%; p < 0.001). In group A, 86% of nodules converted from hot to cold compared with 18% in group B (p < 0.001). CONCLUSIONS: A single session of RFA was effective in restoring euthyroidism in patients with small AFTNs. Nodule volume seems to be a significant predictive factor of the efficacy of RFA in treating AFTN.


Asunto(s)
Ablación por Radiofrecuencia/métodos , Nódulo Tiroideo/rehabilitación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
11.
Eur J Clin Nutr ; 72(1): 30-43, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28488692

RESUMEN

Research has shown that a greater adherence to the Mediterranean diet is associated with a reduced risk of major chronic disease. However, the existing literature leads to debate for different issues, such as the measurement of the adherence to the Mediterranean diet, the use of a wide variety of dietary indices with various food components and the large heterogeneity across the studies. In order to summarise the evidence and evaluate the validity of the association between the adherence to the Mediterranean diet and multiple health outcomes, an umbrella review of the evidence across meta-analyses of observational studies and randomised clinical trials (RCTs) was performed. Thirteen meta-analyses of observational studies and 16 meta-analyses of RCTs investigating the association between the adherence to the Mediterranean diet and 37 different health outcomes, for a total population of over than 12 800 000 subjects, were identified. A robust evidence, supported by a P-value<0.001, a large simple size, and not a considerable heterogeneity between studies, for a greater adherence to the Mediterranean diet and a reduced the risk of overall mortality, cardiovascular diseases, coronary heart disease, myocardial infarction, overall cancer incidence, neurodegenerative diseases and diabetes was found. For most of the site-specific cancers, as well as for inflammatory and metabolic parameters, the evidence was only suggestive or weak and further studies are needed to draw firmer conclusions. No evidence, on the other hand, was reported for bladder, endometrial and ovarian cancers, as well as for LDL (low density lipoprotein)-cholesterol levels.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus/prevención & control , Dieta Mediterránea , Medicina Basada en la Evidencia , Neoplasias/prevención & control , Enfermedades Neurodegenerativas/prevención & control , Cooperación del Paciente , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/mortalidad , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/prevención & control , Diabetes Mellitus/epidemiología , Diabetes Mellitus/mortalidad , Humanos , Incidencia , Metaanálisis como Asunto , Mortalidad , Infarto del Miocardio/epidemiología , Infarto del Miocardio/mortalidad , Infarto del Miocardio/prevención & control , Neoplasias/epidemiología , Neoplasias/mortalidad , Enfermedades Neurodegenerativas/epidemiología , Enfermedades Neurodegenerativas/mortalidad , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados , Revisiones Sistemáticas como Asunto
12.
Haemophilia ; 23(4): e340-e347, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28594476

RESUMEN

INTRODUCTION: Congenital dysfibrinogenemia is a rare qualitative fibrinogen deficiency. Molecular defects that result in dysfibrinogenemia are usually caused by mutations which affect fibrinopeptide release, fibrin polymerization, fibrin cross-linking or fibrinolysis. AIM: Here, we investigated the genetic basis of hypodysfibrinogenemia in two Tunisian siblings with major bleeding. METHODS: Coagulation-related tests were performed on the patients and their family members. Functional analysis was performed in plasma fibrinogen to characterize fibrin polymerization. The sequences of fibrinogen genes were amplified and analysed by sequencing. RESULTS: Coagulation studies revealed a reduced functional and a borderline low antigenic fibrinogen plasma levels with prolonged thrombin and activated partial thromboplastin times. The fibrinogen is also characterized by a markedly impaired polymerization and could incorporate into fibrin fibres to a smaller extent (22%). Mutational screening disclosed a heterozygous single nucleotide deletion (G) at c.1025, resulting in a frameshift mutation (AαGly323GlufsX79) that is predicted to delete a part of the αC-domain containing some of the FXIII cross-linking sites. Both the normal and the aberrant Aα-chain (approximately 43 kDa) were detected by electrophoretic analysis in the patients. CONCLUSION: The new dysfunctional fibrinogen, Mahdia variant, describes its impact on fibrin assembly after the loss of the αC domains which are involved in the lateral aggregation of protofibrils. The study confirms that the truncated Aα-chain could be incorporated into mature fibrinogen molecules.


Asunto(s)
Fibrina/química , Fibrina/genética , Fibrinógenos Anormales/genética , Fibrinógenos Anormales/metabolismo , Multimerización de Proteína , Secuencia de Aminoácidos , Pruebas de Coagulación Sanguínea , Niño , Exones/genética , Femenino , Heterocigoto , Humanos , Masculino , Mutación , Linaje , Estructura Cuaternaria de Proteína
13.
Haemophilia ; 23(4): 583-589, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28306188

RESUMEN

INTRODUCTION: Congenital hypofibrinogenaemia is a quantitative fibrinogen disorder characterized by proportionally decreased levels of functional and antigenic fibrinogen. Mutations accounting for quantitative fibrinogen disorders are relatively frequent in the conserved COOH-terminal globular domains of the γ and Bß chains. The latter mutations are of particular interest since the Bß-chain is considered the rate-limiting chain in the hepatic production of the fibrinogen hexamer. AIM: The aim of this study was to study the molecular pattern of four patients with congenital hypofibrinogenaemia. METHODS: Four novel fibrinogen Bß-chain mutations leading to congenital hypofibrinogenaemia were identified in four women with heterogeneous symptoms. The human fibrinogen beta chain precursor protein sequence (P02675) was obtained from the UniProt database. The resulting models were analysed using swisspdbviewer 4.1.0. RESULTS: Three patients were heterozygous for different missense mutations located in the highly conserved ß nodule: c.882G>C:Arg294Ser (Arg264Ser), c.1298G>T:Trp433Leu (Trp403Leu) and c.1329C>G:Asn443Lys (Asn413Lys). Modelling analyses predicted major structural modifications likely to result in impaired fibrinogen secretion. One patient was heterozygous for an intron 7 donor splice mutation (c.1244 + 1G>A), leading to the complete abolishment of the donor site. CONCLUSIONS: Protein modelling of new causative mutations and comparison of molecular, biochemical and clinical data continue to yield valuable information on the development and course of fibrinogen disorders as well as on the choice of the most appropriate treatments.


Asunto(s)
Afibrinogenemia/genética , Fibrinógeno/química , Fibrinógeno/genética , Mutación , Adolescente , Adulto , Niño , Femenino , Heterocigoto , Humanos , Modelos Moleculares , Estructura Secundaria de Proteína
14.
J Thromb Haemost ; 15(5): 876-888, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28211264

RESUMEN

Essentials Hypodysfibrinogenemia is rarely reported among the congenital fibrinogen disorders. This first systematic literature review led to identification of 51 hypodysfibrinogenemic cases. Diagnosis based only on functional/antigenic fibrinogen ratio may be insufficient. Family studies show an incomplete segregation of mutation with the clinical phenotypes. SUMMARY: Background Hypodysfibrinogenemia is a rare disease characterized by decreased levels of a dysfunctional fibrinogen. It shares features with both hypo- and dysfibrinogenemia, although with specific molecular patterns and clinical phenotypes. Objectives To better define the genetics, the diagnosis and the clinical features of hypodysfibrinogenemia. Patients/Methods A systematic literature search led to 167 records. After removal of duplicates, abstract screening and full-text reviewing, 56 molecular and/or clinical studies were analyzed, including a novel FGB missense mutation in a woman with a mild bleeding phenotype. Results A total of 32 single causative mutations were reported, mainly in the COOH-terminal region of the γ or Aα chains at heterozygous or homozygous state. Seven additional hypodysfibrinogenemias were due to compound heterozygosity. The hypofibrinogenemic phenotypes were a result of an impaired assembly or secretion or an increased clearance of the fibrinogen variant, whereas the dysfibrinogenemic phenotype was mainly a result of a defective fibrin polymerization and an abnormal calcium or tPA binding. Among 51 identified index cases, a functional/antigenic fibrinogen ratio < 0.7 had a sensitivity of 86% for the diagnosis of hypodysfibrinogenemia. Eleven patients (22%) were asymptomatic at time of diagnosis, 23 (45%) had a mild bleeding phenotype with mainly obstetrical or gynecologic-related hemorrhage and 22 (43%) had experienced at least one thrombotic event, including 23 venous and eight arterial thromboses. Conclusions This first systematic review on hypodysfibrinogenemia shows the heterogeneity of causative mutations and that misdiagnosis could occur in relation to the functional and antigenic fibrinogen levels. Family studies reveal an incomplete segregation of the mutation with the clinical phenotype.


Asunto(s)
Afibrinogenemia/genética , Coagulación Sanguínea/genética , Fibrinógeno/genética , Mutación Missense , Adulto , Afibrinogenemia/sangre , Afibrinogenemia/diagnóstico , Pruebas de Coagulación Sanguínea , Análisis Mutacional de ADN , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Heterocigoto , Humanos , Fenotipo
15.
Chem Commun (Camb) ; 53(8): 1405-1408, 2017 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-28079225

RESUMEN

Supramolecular Pd2L4 cages (L = ligand) hold promise as drug delivery systems. With the idea of achieving targeted delivery of the metallacages to tumor cells, the bioconjugation of exo-functionalized self-assembled Pd2L4 cages to peptides following two different approaches is reported for the first time. The obtained bioconjugates were analyzed and identified by high-resolution mass spectrometry.


Asunto(s)
Investigación Biomédica , Compuestos Organometálicos/química , Paladio/química , Péptidos/química , Sistemas de Liberación de Medicamentos , Sustancias Macromoleculares/química , Espectrometría de Masas
16.
BMC Hematol ; 17: 22, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29299315

RESUMEN

BACKGROUND: Abnormal fibrinogens can be caused by clinically silent hereditary mutations. A new case was detected accidentally in an 11-year-old girl when routine pre-operative coagulation tests were performed for nasal turbinate surgery. METHODS: The fibrinogen genes FGA, FGG and FGB were sequenced using standard protocols. The kinetics of fibrin formation were followed by turbidity at 350 nm. Purified fibrinogen was incubated with plasmin, and the degradation products analyzed by SDS/PAGE. The formation of fibrinogen-albumin complexes was analyzed by immunobloting. Fibrin structure was examined in a Nikon Eclipse TE 2000-U laser microscope. Secretion of the variant protein was analyzed directly by reverse phase-electrospray time of flight-mass spectrometry (TOF-MS). RESULTS: DNA sequencing revealed a novel heterozygous g. 3057 C > T mutation in the FGA that predicts a p. Arg104 > Cys substitution, in the proband and her father. Both patients were asymptomatic with low functional and antigen fibrinogen concentrations. The proband's plasma fibrinogen polymerization was almost normal, with a 12% decrease in the final turbidity, while, the father's fibrin formation had a diminished slope and final turbidity (2.5× and 40%, respectively). Aα Arg104 is located at a plasmin cleavage site in the coiled-coil region of fibrinogen. However, the father's fibrinogen plasmin degradation was normal. Although the exchanged Cys introduces an unpaired -SH, immunoblotting showed no fibrinogen-albumin complexes. Furthermore, the plasma clot structure observed by confocal microscopy appeared almost normal. TOF-MS showed that the variant Aα chain was underrepresented in plasma and made up only about 25% of the total. CONCLUSIONS: The low expression of the Aα Arg104 > Cys chain in circulation could account for the observed hypodysfibrinogenemia.

17.
Haemophilia ; 22(6): 898-905, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27640400

RESUMEN

INTRODUCTION: No evidence-based guidelines for the management of patients suffering from afibrinogenaemia and hypofibrinogenaemia are available. AIM AND METHOD: The aim of this study was to harmonize patient's care among invited haemophilia experts from Belgium, France and Switzerland. A Delphi-like methodology was used to reach a consensus on: prophylaxis, bleeding, surgery, pregnancy and thrombosis management. RESULTS: The main final statements are as follows: (i) a secondary fibrinogen prophylaxis should be started after a first life-threatening bleeding in patients with afibrinogenaemia; (ii) during prophylaxis the target trough fibrinogen level should be 0.5 g L-1 ; (iii) if an adaptation of dosage is required, the frequency of infusions rather than the fibrinogen amount should be modified; (iv) afibrinogenaemic patients undergoing a surgery at high bleeding risk should receive fibrinogen concentrates regardless of the personal or family history of bleeding; (v) moderate hypofibrinogenaemic patients (i.e. ≥0.5 g L-1 ) without previous bleeding (despite haemostatic challenges) undergoing a surgery at low bleeding risk may not receive fibrinogen concentrates as prophylaxis; (vi) monitoring the trough fibrinogen levels should be performed at least once a month throughout the pregnancy and a foetal growth and placenta development close monitoring by ultrasound is recommended; (vii) fibrinogen replacement should be started concomitantly to the introduction of anticoagulation in afibrinogenaemic patients suffering from a venous thromboembolic event; and (viii) low-molecular-weight heparin is the anticoagulant of choice in case of venous thromboembolism. CONCLUSION: The results of this initiative should help clinicians in the difficult management of patients with congenital fibrinogen disorders.


Asunto(s)
Afibrinogenemia/complicaciones , Anomalías Congénitas/inmunología , Fibrinógeno/uso terapéutico , Hemorragia/tratamiento farmacológico , Manejo de la Enfermedad , Femenino , Humanos , Embarazo
18.
Haemophilia ; 22(5): 667-75, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27293018

RESUMEN

Congenital fibrinogen disorders are rare diseases affecting either the quantity (afibrinogenaemia and hypofibrinogenaemia) or the quality (dysfibrinogenaemia) or both (hypodysfibrinogenaemia) of fibrinogen. In addition to bleeding, unexpected thrombosis, spontaneous spleen ruptures, painful bone cysts and intrahepatic inclusions can complicate the clinical course of patients with quantitative fibrinogen disorders. Clinical manifestations of dysfibrinogenaemia include absence of symptoms, major bleeding or thrombosis as well as systemic amyloidosis. Although the diagnosis of any type of congenital fibrinogen disorders is usually not too difficult with the help of conventional laboratory tests completed by genetic studies, the correlation between all available tests and the clinical manifestations is more problematic in many cases. Improving accuracy of diagnosis, performing genotype, analysing function of fibrinogen variants and carefully investigating the personal and familial histories may lead to a better assessment of patients' phenotype and therefore help in identifying patients at increased risk of adverse clinical outcomes. This review provides an update of various tests (conventional and global assays, molecular testing, fibrin clot analysis) and clinical features, which may help to better predict the phenotype of the different types of congenital fibrinogen disorders.


Asunto(s)
Afibrinogenemia/diagnóstico , Afibrinogenemia/congénito , Afibrinogenemia/patología , Pruebas de Coagulación Sanguínea , Fibrinógeno/genética , Genotipo , Hemorragia/prevención & control , Humanos , Fenotipo , Trombosis/etiología
19.
Mol Biosyst ; 12(5): 1564-73, 2016 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-26960817

RESUMEN

The pH gating of human AQP3 and its effects on both water and glycerol permeabilities have been fully characterized for the first time using a human red blood cell model (hRBC). For comparison, the effects of pH on the gating of rat AQP3 have also been characterized in yeast. The obtained results highlight similarities as well as differences between the two isoforms. In addition, we investigated the molecular mechanism of hAQP3 pH gating in silico, which may disclose new pathways to AQP regulation by small molecule inhibitors, and therefore may be important for drug development.


Asunto(s)
Acuaporina 3/química , Acuaporina 3/metabolismo , Diseño de Fármacos , Activación del Canal Iónico/efectos de los fármacos , Animales , Acuaporina 3/antagonistas & inhibidores , Acuaporina 3/genética , Línea Celular , Permeabilidad de la Membrana Celular , Clonación Molecular , Simulación por Computador , Expresión Génica , Glicerol/química , Glicerol/metabolismo , Humanos , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Unión Proteica , Conformación Proteica , Transporte de Proteínas , Ratas
20.
Thromb Res ; 137: 189-195, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26577257

RESUMEN

The clinical phenotype of patients with congenital dysfibrinogenaemia is highly heterogeneous, from absence of symptoms to mild bleeding, or thrombosis. A few mutations are associated with a specific phenotype, but generally the clinical course is not predictable. We investigated whether fibrin clot properties are correlated with the patient's phenotype and/or genotype. Ex vivo plasma fibrin clot characteristics, including turbidity, fibrinolysis, clot permeability and fibrin fibre density assessed by laser scanner confocal microscopy were investigated in 24 genotyped patients with congenital dysfibrinogenaemia compared to normal pool plasma. Compared to normal pool plasma, the patients were characterised by slower fibrin polymerisation (lag time, 345.10 ± 22.98 vs. 166.00s), thinner fibrin fibres (maximum absorbance, 0.15 ± 0.01 vs. 0.31), prolonged clot lysis time (23.72 ± 0.97 vs. 20.32 min) and larger clot pore size (21.5×10(-9) ± 4.48×10(-9) vs. 7.96×10(-9)cm(2)). Laser scanning confocal microscopy images confirmed disorganised fibrin networks in all patients. Patients with tendency to bleed showed an increased permeability compared to asymptomatic patients (p=0.01) and to patients with a thrombotic history (p=0.02) while patients with thrombotic history had a tendency to have a prolonged clot lysis time. Fibrin clot properties were similar among hotspot mutations. Further studies including a larger number of patients are needed to evaluate whether analysis of permeability and clot lysis time may help to distinguish the clinical phenotype in these patients and to assess differences according to the genotype.


Asunto(s)
Anemia Diseritropoyética Congénita/sangre , Anemia Diseritropoyética Congénita/patología , Tiempo de Lisis del Coágulo de Fibrina/métodos , Fibrina/metabolismo , Fibrina/ultraestructura , Adulto , Anciano , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Productos de Degradación de Fibrina-Fibrinógeno/ultraestructura , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
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