Hnf4g invalidation prevents diet-induced obesity via intestinal lipid malabsorption

Changes in dietary habits have occurred concomitantly with a rise of type 2 diabetes (T2D) and obesity. Intestine is the first organ facing nutrient ingestion and has to adapt its metabolism with these dietary changes. HNF-4γ, a transcription factor member of the nuclear receptor superfamily and mainly expressed in intestine, has been suggested to be involved in susceptibility to T2D. Our aim was to investigate the role of HNF-4γ in metabolic disorders and related mechanisms. Hnf4g-/- mice were fed high-fat/high-fructose (HF-HF) diet for 6 weeks to induce obesity and T2D. Glucose homeostasis, energy homeostasis in metabolic cages, body composition and stool energy composition, as well as gene expression analysis in the jejunum were analyzed. Despite an absence of decrease in calorie intake, of increase in locomotor activity or energy expenditure, Hnf4g-/- mice fed with HF-HF are protected against weight gain after 6 weeks of HF-HF diet. We showed that Hnf4g-/- mice fed HF-HF display an increase in fecal calorie loss, mainly due to intestinal lipid malabsorption. Gene expression of lipid transporters, Fatp4 and Scarb1 and of triglyceride-rich lipoprotein secretion proteins, Mttp and ApoB are decreased in gut epithelium of Hnf4g-/- mice fed HF-HF, showing the HNF-4γ role in intestine lipid absorption. Furthermore, plasma GLP-1 and jejunal GLP-1 content are increased in Hnf4g-/- mice fed HF-HF, which could contribute to the glucose intolerance protection. The loss of HNF-4γ leads to a protection against a diet-induced weight gain and to a deregulated glucose homeostasis, associated with lipid malabsorption.

3-Methylindole-substituted zinc phthalocyanines for photodynamic cancer therapy

Novel peripherally and non-peripherally 3-methylindole-substituted zinc phthalocyanine derivatives were synthesized as photosensitizers for photodynamic therapy in cancer treatment. The photophysical, photochemical and photobiological properties of targeted phthalocyanines were also investigated. For this purpose, the fluorescence and singlet oxygen quantum yields, and fluorescence lifetime values of the final compounds were determined in DMF solutions. The phototoxicity and cytotoxicity of the phthalocyanine complexes were tested against the invasive human breast cancer cell line (MDA-MB-231) for determination of their photosensitizing ability in the area of photodynamic therapy. It was revealed that while peripherally 3-methylindole-substituted phthalocyanine was found to be toxic for cells in both dark and light conditions, its non-peripherally substituted phthalocyanine analogue significantly caused cell death following light irradiation. A preliminary assay suggested that the non-peripherally linked phthalocyanine could be a suitable candidate for cancer treatment via photodynamic therapy techniques.

Dielectric environment and/or random disorder effects on free, charged and localized excitonic states in monolayer WS2

Excitonic effects play an important role on the optoelectronic behavior of atomically thin two-dimensional (2D) crystals of the WS₂ transition metal dichalcogenide. In this paper, neutral and charged exciton behaviors in monolayer WS₂ are handled within effective-mass approximation for which the critical parameters are ensured from our ab initio calculations. Firstly, we reveal an exciton series with a novel energy dependence on the orbital angular momentum. Considerable control of the dielectric environment on neutral and charged excitons binding energies is elucidated. We demonstrate that for accepted values of effective masses, the negative and positive trion binding energies should be identical. Secondly, localization of neutral exciton center of mass motion by random potential arising from monolayer defects is also studied. The results obtained are in agreement with available experimental work.

Glucose Tolerance Is Improved in Mice Invalidated for the Nuclear Receptor HNF-4γ: A Critical Role for Enteroendocrine Cell Lineage

Intestine contributes to energy homeostasis through the absorption, metabolism, and transfer of nutrients to the organism. We demonstrated previously that hepatocyte nuclear receptor-4α (HNF-4α) controls intestinal epithelium homeostasis and intestinal absorption of dietary lipids. HNF-4γ, the other HNF-4 form highly expressed in intestine, is much less studied. In HNF-4γ knockout mice, we detect an exaggerated insulin peak and improvement in glucose tolerance during oral but not intraperitoneal glucose tolerance tests, highlighting the involvement of intestine. Moreover, the enteroendocrine L-type cell lineage is modified, as assessed by the increased expression of transcription factors Isl1, Foxa1/2, and Hnf4a, leading to an increase of both GLP-1-positive cell number and basal and stimulated GLP-1 plasma levels potentiating the glucose-stimulated insulin secretion. Using the GLP-1 antagonist exendin (9-39), we demonstrate a direct effect of GLP-1 on improved glucose tolerance. GLP-1 exerts a trophic effect on pancreatic β-cells, and we report an increase of the β-cell fraction correlated with an augmented number of proliferative islet cells and with resistance to streptozotocin-induced diabetes. In conclusion, the loss of HNF-4γ improves glucose homeostasis through a modulation of the enteroendocrine cell lineage.

Management of laryngomalacia

Laryngomalacia is the most common laryngeal disease of infancy. It is poorly tolerated in 10% of cases, requiring assessment and management, generally surgical. Surgery often consists of supraglottoplasty, for which a large number of technical variants have been described. This surgery, performed in an appropriate setting, relieves the symptoms in the great majority of cases with low morbidity. However, few data are available concerning the objective results: preoperative and postoperative objective assessment of these infants is therefore necessary whenever possible. Noninvasive ventilation (NIV) may be indicated in some infants with comorbid conditions or failing to respond to surgical management.

Features of EBV reactivation after reduced intensity conditioning unrelated umbilical cord blood transplantation

This single centre study assessed the incidence, kinetics and predictive factors of EBV reactivation and EBV-related lymphoproliferative diseases (LPD) in 33 consecutive patients who received a reduced intensity conditioning (RIC) before umbilical cord blood transplantation (UCBT). During the first 6 months after UCBT, weekly all patients were DNA-PCR screened in the peripheral blood for EBV reactivation and were clinically monitored for clinical features attributable to EBV. The cumulative incidences of EBV reactivation (defined as an EBV load >1000 EBV copies per 10(5) cells measured at least once during follow-up) at 6 months and 2 years after UCBT were 9 (95% confidence interval (CI), 2-22%) and 17% (95% CI, 6-33%), respectively. In 28 patients (85%), the EBV load remained negative at all times, and none of these patients experienced any sign of LPD. Five patients (15%) experienced at least one EBV reactivation episode. EBV reactivation was observed at a median of 132 days (range, 85-438) after UCBT. Two patients developed EBV-related LPD (cumulative incidence, 6% at 3 years). With a median follow-up of 468 days (range, 92-1277) post UCBT, the OS was 62% at 3 years. Five patients died of disease progression and seven patients died of transplant-related complications, including one case of EBV-related LPD. Univariate analysis did not identify any significant risk factor associated with EBV reactivation. We conclude that patients undergoing RIC UCBT are at risk for EBV reactivation, with the need for close EBV monitoring and the use of preemptive rituximab treatment as some cases may progress to life-threatening LPD.

Is there a role for all-trans retinoic acid in combination with recombinant erythropoetin in myelodysplastic syndromes? A report on 59 cases

Erythropoiesis-stimulating agents (ESAs) remain the first-line treatment of anemia in lower risk myelodysplastic syndromes (MDS) without 5q deletion. A preliminary report suggested that adding all-trans retinoic acid (ATRA) to ESAs may improve their erythroid response, particularly in patients with high endogenous erythropoietin (EPO) level, and may improve other cytopenias. We conducted a prospective multicenter study of EPO-beta and ATRA in anemic MDS patients with marrow blasts <10% and either previous ESA failure or relapse, endogenous EPO >500 U/l or other cytopenia(s) (absolute neutrophilic count <1.0 G/l or platelets <50 G/l). A total of 59 patients were evaluable after 12 weeks of treatment. The erythroid response rates according to IWG 2000 and 2006 criteria, respectively, were as follows: overall: 49 and 36%; patients with previous ESA failure (n=28): 43 and 32%; patients with endogenous EPO >500 U/l (n=18): 11 and 19%; patients transfused >2 red blood cells units/month (n=28) 43 and 39%. Only one neutrophil, but no platelet response, and no major side effect were observed. EPO-beta-ATRA combination appears a possible therapeutic option in anemia of MDS having failed an ESA alone, but not in patients with high endogenous EPO level, and does not improve neutropenia and thrombocytopenia.

Contribution of CT-assisted navigation and microdebriders to endoscopic sinus surgery in cystic fibrosis

OBJECTIVE

To demonstrate the interest of CT-assisted navigation and the microdebrider in rhino-sinus surgery for cystic fibrosis.

METHODS

A retrospective study included 20 patients with cystic fibrosis who had undergone endoscopic sinus surgery using CT-assisted navigation and microdebrider between 1998 and 2006.

RESULTS

Surgery was indicated for the following symptoms resistant to medical management: incapacitating nasal obstruction (n=18, 90%) and headache or periorbital pain (n=14, 70%). At 3 years follow-up, six patients (30%) were symptom-free, six (30%) had required re-operation, and symptoms were well controlled by medication in the other eight (40%). Mean initial bilateral surgery time was 61 min. There were no complications.

CONCLUSION

The advent of microdebriders and CT-based navigation has improved endoscopic sinus surgery in cystic fibrosis. It has permitted the control of medication-resistant symptoms, especially nasal obstruction and pain. Precision is satisfactory, with reduced surgery time. No major complications have been observed. Two- or three-step surgery is possible where endoscopic anatomic landmarks have suffered alteration. The resultant control of symptoms encourages extending indications, with repeat procedures, in view of improving patients' quality of life. Further assessment on a larger series will be needed.

[A case of Nasal septum abscess]

INTRODUCTION

Abscess of the nasal septum is a rare and serious infection, because of the complications which it can generate. The authors report a new case of nasal septum abscess probably of dental origin.

OBSERVATION

A 47-year-old man consulted for bilateral nasal obstruction and rhinorrhea for 3 days with fever. The clinical examination as well as TDM imagery revealed a septal abscess. The patient underwent surgical drainage associated to triple antibiotherapy, with a good evolution at the end of 10 days. The etiologic assessment suggested dental infection.

CONCLUSION

This is a rare and serious infection of the nasal septum. This new case of rare abscess of the nasal septum gives us the opportunity to describe out the various etiologies, their management, and to insist on the preventive treatment of this infection.

[Nasal septal abscess: a case report]

INTRODUCTION

The nasal septum abscess is a rare and serious infection because of the complications which can be generated. The authors report a new case of nasal septum abscess to probably from dental origin.

OBSERVATION

A 47 year old man consulted for bilateral nasal obstruction and rhinorrhea for 3 days with an infectious context. The clinical examination as well as the CT scan demonstrated a septal abscess. The patient had a surgical drainage associated with a triple antibiotherapy with favourable evolution at the end of 10 days. The etiologic investigation is in favour of a dental etiology.

CONCLUSION

It is about a rare and serious infectious pathology of the nasal septum. We point out its various etiologies, its management, while insisting on the preventive treatment of this affection.

Tracheotomy in children: evolution in indications

OBJECTIVES

To evaluate the evolution of indications for tracheostomy in children.

METHODS

A retrospective review of 46 children undergoing tracheostomy between 1996 and 2001.

RESULTS

The indications for tracheostomy were classified in two groups:(1) prolonged ventilator dependence (57%), (2) upper airway obstructions (43%). The average age of the tracheostomy was 3 years and 8 months. This was higher in the first group (5.5 years). Decannulation was accomplished in 52%. The indications for tracheostomy were evaluated and were found to decrease in frequency for upper airway obstructions. An increasing indication was for chronic disorders requiring prolonged ventilator dependence. Complications occurred in 50% of children. Overall mortality was 13-2.7% directly related to the tracheostomy.

CONCLUSIONS

Evolving indication has been ventilator dependence. Upper airway obstruction as an indication has diminished in frequency, especially with the concomitant progress of endoscopic techniques.

[Imported malaria in Tunisia]

Thanks to the national programme of malaria eradication carried out between 1968 and 1972, there has been no active transmission of the parasitosis in Tunisia since the last indigenous case in 1979. Since 1980, with the increase in international exchanges especially with sub-Saharian countries, only imported cases of malaria have been reported in Tunisia. A retrospective and thorough survey of malaria cases diagnosed in the laboratory of parasitology of the Pasteur Institute in Tunis from 1980 to 1995 determined the epidemiological characteristics of this imported parasitosis. All in all, during the sixteen years following eradication, 245 cases were registered. The majority of cases (86.2%) was diagnosed by a systematic control of groups at risk within the national programme of malaria eradication. The remaining 13.8% cases sought medical advice when clinical symptoms appeared after their return from endemic countries. The population most affected by imported malaria were men (sex-ratio: 6.8) aged between 20 and 40 years (76% of cases); 38% were Tunisians having sojourned in an endemic country, essentially students from sub-Saharian Africa. The presumed country of contamination was African in 92.7% of the cases. Entrance into Tunisia by patients was mainly by air; 4% of the registered cases had come by land from Algeria. Sound knowledge of the epidemiological characteristics of imported malaria would make for a better follow-up of the affected population and thus reduce the probability of repeated transmission.