Effects of insulin, somatomedin--a multiplication stimulating activity (MSA)--and transferrin, on the lipolysis of rat adipocytes in vitro

Antilipolytic effect was researched when insulin (0.1 and 1 mIU/ml), MSA (200 and 500 ng/ml) and transferrin (2 and 5 micrograms/ml) were added to a suspension of freshly isolated rat adipocytes in vitro. Lipolysis was measured as glycerol secretion in the medium: micromoles/90 minutes/100 mg total lipids. Insulin (1 mIU/ml) reduced adrenalinic stimulation of lipolysis: A 1 microgram/ml (P less than 0.05). MSA 200 ng/ml had no effect. MSA 500 ng/ml reduced basal lipolysis and adrenalinic stimulation (P less than 0.05), and increased insulin-induced antilipolysis (P less than 0.05). Transferrin was active, only when insulin is present: antilipolysis increased (P less than 0.05).     

Synthesis and FTIR Conformational Studies of Peptides From the Basic Region of c-Jun: a Critical Analysis on the Basis of CD and NMR Data

Abstract

The peptide (35 residues) corresponding to the basic subdomain (bSD) of c-Jun (residues 252–281) and its fragments NP (N-terminal peptide, 1–19) and CP (C-terminal peptide, 1635) were synthesized in stepwise solid-phase using the tert-butyloxycarbonyl/benzyl strategy. In a previous paper, we have shown that during its binding to the DNA site CRE (cAMP- responsive element) the bSD structure was converted into α-helix from an initial random coil conformation [Krebs, D., Dahmani, B., El Antri, S., Monnot, M., Convert, O., Mauffret, O., Troalen, F. & Fermandjian, S. Eur. J. Biochem. 231, 370–380 (1995)]. Our results suggested both a high flexibility and a helical potential in bSD, these two properties seeming crucial for the accommodation of the basic subdomain of c-Jun to its specific DNA targets. In this work, we assessed the conformational variability of bSD through the study of the secondary structures of its NP and CP fragments in trifluoroethanol (TFE)/²H₂O mixtures, using Fourier transform infrared (FTIR) spectroscopy. The IR results were critically analyzed in light of our previously reported circular dichroism (CD) and NMR data [Krebs, D., Dahmani, B., Monnot, M., Mauffret, O., Troalen, F. & Fermandjian, S. Eur. J. Biochem. 235, 699–712 (1996)]. Upon addition of TFE, the relative areas of the seven components of the amide I band (1700–1620 cm^?1) reflected the conversion of a large amount of random coil conformation into α-helix for the two fragments and bSD. This effect was accompanied by more subtle variations of the less populated structures, in agreement with the results of CD and NMR experiments. The IR results stipulated the conservation of the parent bSD secondary structures in both fragments; however, NP and CP peptides did not display similar random-to-α-helix stabilization pattern upon additions of TFE to aqueous solutions. The profile from CD signal at 222 nm was found sigmoidal for NP and almost linear for CP, while that corresponding to the parent peptide bSD was just in between those of its fragments. Thus, the present study confirms the high flexibility and helix propensity of the c-Jun basic subdomain and suggests that the N- and C-terminal parts of the peptide do not follow the same random-to-helix conversion profile during their complexation with DNA.     

Use of Taguchi's methods as a basis to optimize hybridoma cell line growth and antibody production in a spinner flask

Taguchi’s methods were used for the design of an experimental strategy aimed at optimizing cell density and monoclonal antibody (mAb) production from a spinner flask hybridoma culture. 23G11 is an antibody to the human leukocyte adhesion molecule, CR3 or β 2 integrin (CD11b/CD18). It recognizes specifically the A-domain of the α subunit CD11b. Anti β 2 integrin monoclonal antibodies hold a great potential for preventing inflammation mediated tissue injuries. An L8 orthogonal experimental design was used to investigate four different culture components: stirring speed, nature of serum, concentration of serum and nature of media (RPMI 1640 or RPMI 1640 supplemented with glucose and glutamine). The experiments were conducted using two levels for each factor studied and a direct ELISA test was used to estimate the level of antibody production. Statistical analysis of the collected data pointed to the stirring speed and serum concentration, and the interaction between these parameters, as the components that affected cell growth. Antibody production was affected by these factors and by the nature of medium but also by the following two interactions: stirring speed/nature of serum and stirring speed/concentration of serum. This study emphasizes the value of using Taguchi’s methods as a basis for optimization of mAb production from a hybridoma culture, in cost effective and significantly less labor intensive ways. This revised version was published online in August 2006 with corrections to the Cover Date.     

Human mitochondrial variants influence on oxygen consumption

This work investigates if human mitochondrial variants influence on maximal oxygen consumption (VO(2max)). With this purpose we recruited, as a uniform population in term of nutritional habits and life style, 114 healthy male Spanish subjects that practiced fitness exercises 3-4 times a week. Once mtDNA haplogroups were determined, we found that J presents with lower VO(2max) (P=0.02) than nonJ variants. J has been related with a lower efficiency of electron transport chain (ETC), diminished ATP and ROS production. Thus, the difficult to compensate the mitochondrial energetic deficiency could explain the accumulation of J haplogroup in LHON and multiple sclerosis. Furthermore, the lower ROS production associated to J could also account for the accrual of this variant in elderly people consequent to a decreased oxidative damage.     

Thermoreversible gelation in aqueous binary solvents of chemically modified agarose

The thermoreversible gelation of chemically modified agarose has been studied in aqueous binary solvents (dimethyl sulfoxide and a series of formamide) by differential calorimetry, mechanical testing, and small-angle neutron scattering. The temperature–composition phase diagrams have been established. It is concluded that gelation is promoted by the formation of ternary complexes modified agarose/water/cosolvent, wherein the cosolvent mediates the interaction between chains through the formation of electrostatic interactions.     

A Qualitative Study of Vaccine Acceptability and Decision Making among Pregnant Women in Morocco during the A (H1N1) pdm09 Pandemic

Vaccination uptake of pregnant women in Morocco during the A (H1N1) pdm09 pandemic was lower than expected. A qualitative study using open-ended questions was developed to explore the main determinants of acceptance and non-acceptance of the monovalent A (H1N1) pdm09 vaccine among pregnant women in Morocco and to identify information sources that influenced their decision-making process. The study sample included 123 vaccinated and unvaccinated pregnant women who were in their second or third trimester between December 2009 and March 2010. They took part in 14 focus group discussions and eight in-depth interviews in the districts of Casablanca and Kenitra. Thematic qualitative analysis identified reasons for vaccine non-acceptance: (1) fear of the monovalent A (H1N1) pdm09 vaccine, (2) belief in an A (H1N1) pdm09 pandemic conspiracy, (3) belief in the inapplicability of the monovalent A (H1N1) pdm09 vaccine to Moroccans, (4) lack of knowledge of the monovalent A (H1N1) pdm09 vaccine, and (5) challenges of vaccination services/logistics. Reasons for vaccine acceptance included: (1) perceived benefits and (2) modeling. Decision-making was strongly influenced by family, community, mass media, religious leaders and health providers suggesting that broad communication efforts should also be used to advocate for vaccination. Meaningful communication for future vaccine campaigns must consider these context-specific findings. As cultural and religious values are shared across many Arab countries, these findings may also provide valuable insights for seasonal influenza vaccine planning in the Middle East and North Africa region at large.     

Steady exercise removes VO2max difference between mitochondrial genomic variants

It has been clearly established that mitochondrial variants, among other potential factors, influence on VO_2max. With this study we sought to determine whether this genetic predisposition could be modified by steady exercise. Mitochondrial genetic variants were determined in 70 healthy controls (CON) and in 77 athletes who trained regularly (50 cyclists, aerobic training (AER), and 27 runners of 400 m, anaerobic training (NoAER)). All of them were male Spanish Caucasian individuals. A maximum graded exercise test (GXT) in cycle-ergometer was performed to determine VO_2max (mL kg⁻¹ min⁻¹). Our results confirmed that, in CON, VO_2max (P = 0.007) was higher in Non-J than J individuals. Furthermore, we found that AER and NoAER showed, as it could be expected, higher VO_2max than CON, but not differences between mitochondrial variants have been found. According with these findings, the influence of mitochondrial DNA (mtDNA) variants on VO_2max has been confirmed, and a new conclusion has arisen: the steady exercise is able to remove this influence. The interest of these promising findings in muscular performance should be further explored, in particular, the understanding of potential applications in sport training and in muscle pathological syndromes.     

Analysis of MIF,FCGR2A and FCGR3A gene polymorphisms with susceptibility to pulmonary tuberculosis in Moroccan population

In order to investigate the influence of functional polymorphisms of macrophage migration inhibitory factor(MIF),Fcg receptors CD16A(FCGR3A) and CD32A (FCGR2A) genes on susceptibility to pulmonary tuberculosis(PTB)in the Moroccan population,we analyzed 123 patients with PTB and 154 healthy controls.The genotyping for MIF-173(G/C)(rs755622),FCGR2A-131H/R(rsl801274)and FCGR3A-158V/F(rs396991) was carried out using TaqMan SNP Genotyping Assay method.We found a statistically significant increase of the MIF-173CC homozygote genotype and MIF-173*C allele frequencies in PTB patients compared with healthy controls (17.07%versus 5.84%,P=0.003;and 35.37%versus 26.30%,P=0.02;respectively).In contrast,no association was observed between CGR2A-131H/R and FCGR3A-158V/F polymorphisms and tuberculosis disease.Our finding suggests that MIF-173*C variant may play an important role in the development of active tuberculosis.