High-dose infliximab prophylaxis in endotoxin-induced uveitis.

PURPOSE: The aim of this study to analyze the preventive effect of high-dose infliximab in endotoxin-induced uveitis (EIU) in rabbits. METHODS: An experimental study was conducted on 64 rabbits. Salmonella typhimurium lipopolysaccharide endotoxin was intravitreally injected. Infliximab was intravenously (i.v.) injected 24 h before the intravitreal injection (20 mg/kg). The animals were randomly assigned to five groups: group A, saline intravitreal injection; group B, Infliximab i.v. group C, infliximab + saline; group D, intravitreal endotoxin and group E, infliximab i.v. + intravitreal endotoxin. With two masked observers, a microscopic examination of aqueous humor (cells, tumor necrosis factor [TNF] alpha) and aqueous protein level were performed 24 h after an endotoxin injection and 48 h after an infliximab infusion. RESULTS: Infliximab treatment, at a dose of 20 mg/kg, significantly improved all the parameters. Inflammatory cell infiltration was significantly reduced in the iris, ciliary body, and anterior chamber (U Mann-Whitney test, P = 0.01). Associated with a lower level of TNF-alpha and protein exudate in aqueous humor (U Mann-Whitney test, P = 0.01). CONCLUSIONS: Infliximab, at a dose of 20 mg/kg, is effective in the prophylaxis of the EIU.     

Optimization and upscaling of doxorubicin-containing liposomes for clinical use

This work describes the optimization of a doxorubicin (DXR)-containing liposome formulation and its upscaling for human therapy. Multilamellar vesicles (MLV) composed of egg phosphatidylcholine, egg-derived phosphatidylglycerol, cholesterol, and the drug were prepared in 0.9% sterile, pyrogen-free NaCl by five different hydration methods. The optimal hydration was shown to be the formation of a thin lipid film with high surface area. Alternative hydration methods based on freeze-drying techniques of the lipids in tertiary butanol or based on "alcohol" premixing procedures of the dry DXR-lipid mixture showed smaller DXR loading capacities and lower DXR incorporation per phospholipid. Maximal DXR entrapment was obtained at a molar concentration of phosphatidylglycerol of 30 mol % of total phospholipid. This and previous studies led to a final lipid composition of phosphatidylcholine:phosphatidylglycerol:cholesterol in a molar ratio of 7:3:4. Oligolamellar DXR-liposomes with an average diameter in the range 0.3-0.5 microM were prepared from DXR-MLV by extrusion through polycarbonate membranes using moderate pressures (up to 100 psi). At this size range, maximal entrapment of DXR per phospholipid was obtained. The extrusion process also ensures the sterilization of the final product. Free DXR was removed from liposome-associated DXR (L-DXR) by the use of a cation-exchange resin. The L-DXR formulation was shown to have reasonable stability on storage at 4 degrees C.     

Primary ciliary dyskinesia gene contribution in Tunisia: Identification of a major Mediterranean allele

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disease of motile cilia. Even though PCD is widely studied, North‐African patients have been rarely explored. In this study, we aim at confirming the clinical diagnosis and explore the genetic spectrum of PCD in a cohort of Tunisian patients. Forty clinically diagnosed patients with PCD belonging to 34 families were recruited from Tunisian pediatric departments. In each proband, targeted capture PCD panel sequencing of the 40 PCD genes was performed. PCD panel sequencing identified bi‐allelic mutations in 82% of the families in eight PCD genes. Remarkably, 23.5% of patients carried the same c.2190del CCDC39 mutation. Single nucleotide polymorphism profiling in six unrelated patients carrying this mutation has revealed a founder effect in North‐African patients. This mutation is estimated to date back at least 1,400–1,750 years ago. The identification of this major allele allowed us to suggest a cost‐effective genetic diagnostic strategy in North‐African patients with PCD.     

Current approaches for deciphering the molecular basis of combined anterior pituitary hormone deficiency in humans

This review focuses on the general strategies currently used to decipher the molecular bases of combined pituitary hormone deficiency (CPHD) of genetic origin. By summarizing illustrative approaches that turned out to be successful for identifying an increasing number of genes involved in CPHD in the human, this article consider predictable obstacles specific to the investigation of these rare and heterogeneous conditions, while underlining the previously unsuspected roles of several of these genes during the development of extrapituitary structures.     

A 5'' splice-region G----C mutation in exon 1 of the human beta-globin gene inhibits pre-mRNA splicing: a mechanism for beta+-thalassemia.

We have characterized a Mediterranean beta-thalassemia allele containing a sequence change at codon 30 that alters both beta-globin pre-mRNA splicing and the structure of the hemoglobin product. Presumably, this G----C transversion at position -1 of intron 1 reduces severely the utilization of the normal 5' splice site since the level of the Arg----Thr mutant hemoglobin (designated hemoglobin Kairouan) found in the erythrocytes of the patient is very low (2% of total hemoglobin). Since no natural mutations of the guanine located at position -1 of the CAG/GTAAGT consensus sequence had been isolated previously, we investigated the role of this nucleotide in the constitution of an active 5' splice site by studying the splicing of the pre-mRNA in cell-free extracts. We demonstrate that correct splicing of the mutant pre-mRNA is 98% inhibited. Our results provide further insights into the mechanisms of pre-mRNA maturation by revealing that the last residue of the exon plays a role at least equivalent to that of the intron residue at position +5.