Lipid composition of Quaking mouse myelin: comparison with normal mouse myelin in the adult and during development

Abstract— In the ‘Quaking’ mouse, a deficiency in the long chain fatty acid content of galactolipids has been shown to occur. Myelin in the mutant has been compared to myelin in adult and in 12-day-old controls. We have shown that myelin is not only quantitatively reduced but also qualitatively modified, with a higher protein and a lower galactolipid content. Cerebrosides contain only a small amount of kerasin, lacking long chain nonhydroxylated fatty acids in comparison to both controls; the relative percentage of phrenosin is increased. Although many similarities exist between adult Quaking myelin and myelin at 12 days, differences have been shown to occur which may be in relation to a genetic block at an earlier stage of development.     

Structure and expression of a cDNA encoding a histone H2A from Euglena gracilis

Screening of a gt11 cDNA expression library of Euglena gracilis with antibodies directed against histones H2 from maize resulted in the isolation of a full-length cDNA for a histone H2A. The open-reading frame of 408 bp corresponded to a protein of 136 amino acid residues (14 kDa). Despite the presence of a poly(A) tail, which is typical of plant histone mRNA but not of animal histone mRNA, the size of the deduced protein and its percentage of homology were closer to animal histone H2As than to plant or lower eukaryotic histone H2A.Sequence alignment revealed that the Euglena H2A protein was characterized by a shorter C-terminus and a N-terminus which extended 10 residues past the animal H2A.     

Cytostatic drugs differentially affect phenotypic features of porcine coronary artery smooth muscle cell populations

We studied the effects of cytostatic drugs on porcine coronary artery spindle-shaped (S) and rhomboid (R) smooth muscle cell (SMC) biological activities related to intimal thickening (IT) formation. Imatinib, and to a lesser extent curcumin, decreased proliferation of S- and R-SMCs and migratory and urokinase activities of R-SMCs more efficiently compared with cyclosporine plus rapamycin. Imatinib increased the expression of alpha-smooth muscle actin in both SMC populations and that of smoothelin in S-SMCs. It decreased S100A4 expression in R-SMCs. By promoting SMC quiescence and differentiation imatinib and curcumin may represent valid candidates for restenosis preventive and therapeutic strategies.     

Identification of self-renewing myoblasts in the progeny of single human muscle satellite cells

We demonstrate that self-renewing myoblasts can be identified in the progeny of single human muscle satellite cells (HMSC) in culture. We show, using cytoskeletal proteins and cell size as markers, that self-renewing myoblasts are phenotypically different from other myoblasts, but similar to native HMSC. Native desmin-positive HMSC, cultured as single cells, yielded two major populations of myoblasts, α-sarcomeric (α-SR)-actin-positive myoblasts and desmin-positive myoblasts. In appropriate culture conditions, α-SR-actin-positive myoblasts fused into myotubes, whereas a population of desmin-positive non-fusing myoblasts (NFMB) persisted for weeks among the myotubes. Upon isolation from myotubes, some of the NFMB resumed proliferation and their progeny included fusing and non-fusing myoblasts, with the same cytoskeletal phenotypes as the progeny of native HMSC. This self-renewal cycle could be repeated, yielding four cohorts of myoblasts. The yield of self-renewing cells appeared to decrease with the number of cycles. These results suggest that stem cells are present among NFMB. Moreover, we find that these presumptive stem cells are already segregated during myoblast proliferation. They are small, phenotypically similar to native HMSC, and do not divide unless they are isolated from their sister progeny and cultured alone. Enriched preparations of cells with stem cell-like properties can be obtained from proliferating myoblasts by flow cytometry on the basis of size and nucleocytoplasmic ratio.     

Fibrate treatment induced quantitative and qualitative HDL changes associated with an increase of SR-BI cholesterol efflux capacities in rabbits

Fibrates are widely used as lipid lowering drugs acting as peroxisome proliferator-activated receptors α (PPARα) agonists and modulating the expression of several genes involved in lipid and lipoprotein metabolism. Much less is known on the effect of fibrates in HDL structure and composition. Therefore, we examined whether fenofibrate induces quantitative and/or qualitative modifications in HDL metabolism in the rabbit, an animal that, contrary to rodents and similar to humans, is less sensitive to peroxisome proliferators. We first demonstrated that 3-week treatment with fenofibrate (250 mg/kg/day) induced an important increase in serum apolipoprotein A-I, HDL-cholesterol and HDL-phospholipids concentrations and a relative enrichment in HDL cholesteryl ester content. Moreover, the fatty acid profiles from fenofibrate-treated rabbits displayed a dramatic increase in the serum or HDL C18:3 ω6 to C18:2 ω6 ratio suggesting higher Δ6 desaturase activity. In addition, HDL from fenofibrate-treated animals exhibited higher relative proportions of sphingomyelin, phosphatidylinositol and phosphatidylethanolamine. We then reported that fenofibrate induced major changes in the physical characteristics of HDL, mainly a higher size and a faster mobility on agarose gel electrophoresis. Finally, serum or HDL from treated rabbits exhibited higher capacity to promote cholesterol efflux from Scavenger receptor class B type I (SR-BI)-rich Fu5AH cells compared to controls. Our findings demonstrate that fenofibrate has beneficial effects in rabbits by increasing the mass of the circulating HDL pool and by modifying their composition transforming them as better acceptors of cellular cholesterol through SR-BI pathway. These effects of fenofibrate might contribute to its benefits on the prevention and treatment of atherosclerosis.     

Immune response to vaccination with DNA encoding the bovine viral diarrhea virus major glycoprotein gp53 (E2)

Bovine viral diarrhea virus (BVDV) is a worldwide pathogen in cattle which has not been controlled by classical vaccination. The region encoding the BVDV major glycoprotein gp53 (E2) known to possess virus-neutralizing activity was cloned into a mammalian expression vector under the human cytomegalovirus (CMV) intermediate early promoter. Intramuscular and intradermal administration of the recombinant plasmid DNA into BALB/c mice induced BVDV gp53-specific antibody responses to both biotypes (cytopathic and noncytopathic) of BVDV genotype 1, and to cytopathic BVDV genotype 2. BVDV-neutralizing antibodies were generated against BVDV genotype 1 strains and they also persisted 6 months after the last injection.     

Brain Gangliosides of Quaking and Shiverer Mutants: Qualitative and Quantitative Changes of Monosialogangliosides in the Quaking Brain

Ganglioside compositions in the brains of the mutant mice quaking and shiverer were compared with those of their littermate controls, C57BL/6 and C3HSWV. Neither ganglioside content nor composition of shiverer brains differed from those of the control brains. Change in the ganglioside composition of the mutant brain from that of the control was observed only in the quaking mutant brain, in which monosialoganglioside GM1 was significantly reduced and GM4 was completely absent. The structures of the gangliosides were determined by negative ion fast atom bombardment mass spectrometry, and the GM3 and GM4 gangliosides in the quaking brain were found to be altered in regard to their long-chain base and fatty acid compositions when compared to the normal C57BL/6 brain.     

An Exploratory Analysis of the Utility of Adding Cardiorespiratory Biofeedback in the Standard Care of Pregnancy-Induced Hypertension

This study examined the efficacy of a cardiorespiratory biofeedback intervention compared to bed rest in the treatment of 47 women diagnosed with pregnancy-induced hypertension (PIH). The investigation consisted of a historical control group with 31 PIH subjects receiving treatment as usual (TAU), bed rest and antihypertensive medications, and an experimental group with 16 PIH subjects receiving TAU and instruction on using a portable respiratory sinus arrhythmia (RSA) biofeedback device once daily until delivery. Results indicated that systolic and diastolic blood pressure levels were unchanged for either group. Failing to find the intended main effects, a series of exploratory analyses were performed. Findings of associated hypotheses revealed that the RSA BF group had a 35 % higher birth weight than the TAU group. The gestational age at delivery was 10 % greater in the RSA BF group than in the TAU group. A significant relationship was found between the StressEraser Total and the 1-min Apgar score. Eighty-one percent of the subjects stated that the device was relaxing. Fifty percent of the subjects believed that the device helped them fall asleep. Overall, these results suggest that portable RSA biofeedback may be effective in reducing stress during pregnancy and improving perinatal outcomes.