Complete Atrioventricular Canal Defect: Towards a More Physiological Repair.

We describe a more physiological technique of complete atrioventricular septal defect repair which restores normal heart anatomy with the offset between the insertions of the mitral and tricuspid valves. This technique overcomes the drawbacks of the previous approaches, and may improve surgical outcomes, particularly in small infants with high ventricular septal defect component or dextroposed aorta.

Simulation of a computed HbA1c using a weighted average glucose.

BACKGROUND: The A1c-derived average glucose examined the link between the glycated haemoglobin and the estimated average glucose, and provided a linear relation between them. Other studies proved that, over a period of 4 months, plasma glucose in the preceding 30 days contribute to about 50 % to the glycated haemoglobin value while the other 50 % is due to the remaining 3 months altogether. TECHNICAL DETAILS OF THE METHOD: In this technical note, we propose a weighted method assuming that the contribution of glucose to glycated haemoglobin over 3 months is chronologically 20 %, 30 % and 50 % respectively. A comparison is made with the linear regression method which uses the same estimated average glucose over the whole period. Results yielded by the weighted method are also compared to those given by the model proposed by Ladyzynski et al. FINDINGS: A simulation is carried out on data assumed to come from a first individual with nearly the same level of glucose over 3 months, a second individual who starts with high levels of glucose and then reaches a stabilised low level by the last month, and finally, a third case who had just been diagnosed with diabetes during the last month whereas he/she had a normal glycaemia during the preceding 2 months. The weighted method gives more realistic values of HbA1c (7.36 %, 6.80 %, 8.49 %) than the linear regression method without weights which gives the same value (7.45 %) for the three cases. Another comparison shows that the three values given by the weighted method are slightly smaller than the corresponding values given by the model of Ladyzynski et al. (7.62 %, 7.02 %, 8.8 %) but the relative variation is nearly the same for the three values (≈3 %). CONCLUSSION: Without regular self-testing and day-to-day insights, a sole HbA1c value can be confusing and misleading. For physicians and patients, a clear understanding of the relationship between the weighted average glucose and HbA1c is necessary in order to set an appropriate daily control depending on whether the glucose is stabilized over the whole period, at the beginning, at the end; or still under recurrent episodes of high and low levels. The measured HbA1c at a biological laboratory gives no indication on glucose variation. Moreover, low values of glucose may cancel high values and lead to a "good" average glucose and ideal glycated haemoglobin.

[Aortic infective endocarditis: Value of surgery. About 48 cases]. / Endocardite infectieuse aortique : intérêt de la chirurgie. À propos de 48 cas.

INTRODUCTION: Infective endocarditis (IE) is a serious disease whose prognosis depends on early management. Aortic location is characterized by its evolution toward myocardial failure and the high number of complications reasons for early surgery. AIM: To compare the short- and mid-terms results of surgery for aortic infective endocarditis (IE) in the active phase and the healed phase. PATIENTS AND METHODS: We analyzed retrospectively the data of 48 consecutive patients operated for aortic infective endocarditis between January 2000 and January 2012. The data on operative mortality, morbidity and major cardiovascular events (mortality, recurrent endocarditis, reintervention, and stroke) were analyzed. RESULTS: Twenty-three patients (48%) underwent surgery during the active phase (group I), 19 on native and 4 on prosthetic valves, and 25 patients (52%) were operated during healed endocarditis (group II) only on native valve. Mean age was 39 years (12-81) with a male predominance (83%). Rheumatic valvular disease was the main etiology of underlying valvular disease in both groups (85%). The clinical feature was dominated by signs of cardiogenic shock in group I and dyspnea exertion stage III-IV NYHA in group II. Streptococcus and Staphylococcus germs were most frequently encountered. Indication for surgery was heart failure in group I, it was related to the symptoms, the severity of valvular disease and its impact on the left ventricle in group II. An aortic valve replacement with a mechanical prosthesis was performed in the majority of cases (83%). Postoperative mortality concerned only one patient in group I. Twenty-one patients (44%) were followed for a mean of 30 months (1-72). One patient in group II died following cerebral hemorrhagic stroke related to accident with vitamin K antagonist. In both groups, there was an improvement in the functional class. No recurrence of endocarditis was noted in both groups during follow-up. CONCLUSION: The prognosis of infective endocarditis of the aortic valve is severe due to the fast progression to heart failure. Early medical and surgical approach provides good results on morbidity and mortality in the short- and mid-terms.

Mitral valve replacement as unusual cause of discrete sub-aortic membrane.

We report the case of 50 year-old woman who presented with left ventricle outflow tract obstruction with discrete sub-aortic membrane 20 years following mitral valve replacement and tricuspid valve annuloplasty. We aim through this case, on one hand to report this unusual entity and on the other hand to discuss the underlying mechanisms as well as the therapeutic solutions.

[Protein tyrosine kinase inhibitors in cancer therapy]. / Bilan des inhibiteurs de protéine tyrosine kinase dans le traitement des cancers.

The tyrosine kinase inhibitors (TKI) are small molecules of low molecular weight that inhibit tyrosine kinases, enzymes responsible for the activation of signal transduction cascades. Currently, a number of TKI received approval in various cancers, while others are in clinical development process: TKI are specifically clinically active when they target a tyrosine kinase (TK) with constitutional activity subsequent to a mutation, being then a master-gene driving transformation and tumour progression. Already, this drug-family provides a major therapeutic weapon against cancer.

A critical review of mathematical models and data used in diabetology.

The literature dealing with mathematical modelling for diabetes is abundant. During the last decades, a variety of models have been devoted to different aspects of diabetes, including glucose and insulin dynamics, management and complications prevention, cost and cost-effectiveness of strategies and epidemiology of diabetes in general. Several reviews are published regularly on mathematical models used for specific aspects of diabetes. In the present paper we propose a global overview of mathematical models dealing with many aspects of diabetes and using various tools. The review includes, side by side, models which are simple and/or comprehensive; deterministic and/or stochastic; continuous and/or discrete; using ordinary differential equations, partial differential equations, optimal control theory, integral equations, matrix analysis and computer algorithms.

A mathematical model for the burden of diabetes and its complications.

BACKGROUND: The incidence and prevalence of diabetes are increasing all over the world. Complications of diabetes constitute a burden for the individuals and the whole society. METHODS: In the present paper, ordinary differential equations and numerical approximations are used to monitor the size of populations of diabetes with and without complications. RESULTS: Different scenarios are discussed according to a set of parameters and the dynamical evolution of the population from the stage of diabetes to the stage of diabetes with complications is clearly illustrated. CONCLUSIONS: The model shows how efficient and cost-effective strategies can be obtained by acting on diabetes incidence and/or controlling the evolution to the stage of complications.

A model of dengue fever.

BACKGROUND: Dengue is a disease which is now endemic in more than 100 countries of Africa, America, Asia and the Western Pacific. It is transmitted to the man by mosquitoes (Aedes) and exists in two forms: Dengue Fever and Dengue Haemorrhagic Fever. The disease can be contracted by one of the four different viruses. Moreover, immunity is acquired only to the serotype contracted and a contact with a second serotype becomes more dangerous. METHODS: The present paper deals with a succession of two epidemics caused by two different viruses. The dynamics of the disease is studied by a compartmental model involving ordinary differential equations for the human and the mosquito populations. RESULTS: Stability of the equilibrium points is given and a simulation is carried out with different values of the parameters. The epidemic dynamics is discussed and illustration is given by figures for different values of the parameters. CONCLUSION: The proposed model allows for better understanding of the disease dynamics. Environment and vaccination strategies are discussed especially in the case of the succession of two epidemics with two different viruses.

The effect of physical exercise on the dynamics of glucose and insulin.

Regular physical activity is indicated either to prevent and delay the onset of non-insulin-dependent diabetes or to assure a good control of diabetes by increasing insulin sensitivity and ameliorating the metabolism of glucose disappearance. Many studies and experiments have dealt with this subject. In this paper, we introduce the effect of physical activity via parameters of a mathematical model which allows us to compare the behaviour of blood glucose in normal, non-insulin-dependent diabetes and insulin-dependent diabetes people, with and without physical effort. Extreme cases of physical activity leading to hypoglycaemia or aggravating hyperglycaemia are also underlined.