Synthesis and biological evaluation of thiazolidine-2-one 1,1-dioxide as inhibitors of Escherichia coli beta-ketoacyl-ACP-synthase III (FabH)

A series of cyclic sulfones has been synthesized and their activity against beta-ketoacyl-ACP-synthase III (FabH) has been investigated. The compounds are selectively active against Escherichia coli FabH (ecFabH), but not Mycobacterium tuberculosis FabH (mtFabH) or Plasmodium falciparum KASIII (PfKASIII). The activity against ecFabH ranges from 0.9 to >100microM and follows a consistent general SAR trend. Many of the compounds were shown to have antimalarial activity against chloroquine (CQ)-sensitive (D6) P. falciparum (IC(50)=5.3microM for the most potent inhibitor) and some were active against E. coli (MIC=6.6microg/ml for the most potent inhibitor).     

CD117+ amniotic fluid stem cells: State of the art and future perspectives

Broadly multipotent stem cells can be isolated from amniotic fluid by selection for the expression of the membrane stem cell factor receptor c-Kit, a common marker for multipotential stem cells. They have clonogenic capability and can be directed into a wide range of cell types representing the three primary embryonic lineages. Amniotic fluid stem cells maintained for over 250 population doublings retained long telomeres and a normal karyotype. Clonal human lines verified by retroviral marking were induced to differentiate into cell types representing each embryonic germ layer, including cells of adipogenic, osteogenic, myogenic, endothelial, neuronal and hepatic lineages. AFS cells could be differentiate toward cardiomyogenic lineages, when co-cultured with neonatal cardiomyocytes, and have the potential to generate myogenic and hematopoietic lineages both in vitro and in vivo. Very recently first trimester AFS cells could be reprogrammed without any genetic manipulation opening new possibilities in the field of fetal/neonatal therapy and disease modeling. In this review we are aiming to summarize the knowledge on amniotic fluid stem cells and highlight the most promising results.     

Similar health benefits of endurance and high-intensity interval training in obese children

Purpose

To compare two modalities of exercise training (i.e., Endurance Training [ET] and High-Intensity Interval Training [HIT]) on health-related parameters in obese children aged between 8 and 12 years.

Methods

Thirty obese children were randomly allocated into either the ET or HIT group. The ET group performed a 30 to 60-minute continuous exercise at 80% of the peak heart rate (HR). The HIT group training performed 3 to 6 sets of 60-s sprint at 100% of the peak velocity interspersed by a 3-min active recovery period at 50% of the exercise velocity. HIT sessions last ∼70% less than ET sessions. At baseline and after 12 weeks of intervention, aerobic fitness, body composition and metabolic parameters were assessed.

Results

Both the absolute (ET: 26.0%; HIT: 19.0%) and the relative VO₂ peak (ET: 13.1%; HIT: 14.6%) were significantly increased in both groups after the intervention. Additionally, the total time of exercise (ET: 19.5%; HIT: 16.4%) and the peak velocity during the maximal graded cardiorespiratory test (ET: 16.9%; HIT: 13.4%) were significantly improved across interventions. Insulinemia (ET: 29.4%; HIT: 30.5%) and HOMA-index (ET: 42.8%; HIT: 37.0%) were significantly lower for both groups at POST when compared to PRE. Body mass was significantly reduced in the HIT (2.6%), but not in the ET group (1.2%). A significant reduction in BMI was observed for both groups after the intervention (ET: 3.0%; HIT: 5.0%). The responsiveness analysis revealed a very similar pattern of the most responsive variables among groups.

Conclusion

HIT and ET were equally effective in improving important health related parameters in obese youth.     

Nutrient-dependent requirement for SOD1 in lifespan extension by protein restriction in Drosophila melanogaster

Reactive oxygen species (ROS) modulate aging and aging-related diseases. Dietary composition is critical in modulating lifespan. However, how ROS modulate dietary effects on lifespan remains poorly understood. Superoxide dismutase 1 (SOD1) is a major cytosolic enzyme responsible for scavenging superoxides. Here we investigated the role of SOD1 in lifespan modulation by diet in Drosophila. We found that a high sugar-low protein (HS-LP) diet or low-calorie diet with low-sugar content, representing protein restriction, increased lifespan but not resistance to acute oxidative stress in wild-type flies, relative to a standard base diet. A low sugar-high protein diet had an opposite effect. Our genetic analysis indicated that SOD1 overexpression or dfoxo deletion did not alter lifespan patterns of flies responding to diets. However, sod1 reduction blunted lifespan extension by the HS-LP diet but not the low-calorie diet. HS-LP and low-calorie diets both reduced target of rapamycin (TOR) signaling and only the HS-LP diet increased oxidative damage. sod1 knockdown did not affect phosphorylation of S6 kinase, suggesting that SOD1 acts in parallel with or downstream of TOR signaling. Surprisingly, rapamycin decreased lifespan in sod1 mutant but not wild-type males fed the standard, HS-LP, and low-calorie diets, whereas antioxidant N-acetylcysteine only increased lifespan in sod1 mutant males fed the HS-LP diet, when compared to diet-matched controls. Our findings suggest that SOD1 is required for lifespan extension by protein restriction only when dietary sugar is high and support the context-dependent role of ROS in aging and caution the use of rapamycin and antioxidants in aging interventions.     

Viral Glycoproteins Accumulate in Newly Formed Annulate Lamellae following Infection of Lymphoid Cells by Human Herpesvirus 6

Ultrastructural analysis of HSB-2 T-lymphoid cells and human cord blood mononuclear cells infected with human herpesvirus 6 revealed the presence, in the cell cytoplasm, of annulate lamellae (AL), which were absent in uninfected cells. Time course analysis of the appearance of AL following viral infection showed that no AL were visible within the first 72 h postinfection and that their formation correlated with the expression of the late viral glycoprotein gp116. The requirement of active viral replication for AL neoformation was further confirmed by experiments using inactivated virus or performed in presence of the viral DNA polymerase inhibitor phosphonoacetic acid. Both conventional electron microscopic examination and immunogold fracture labeling with anti-endoplasmic reticulum antibodies indicated a close relationship of AL with the endoplasmic reticulum and nuclear membranes. However, when the freeze-fractured cells were immunogold labeled with an anti-gp116 monoclonal antibody, AL membranes were densely labeled, whereas nuclear membranes and endoplasmic reticulum cisternae appeared virtually unlabeled, showing that viral envelope glycoproteins selectively accumulate in AL. In addition, gold labeling with Helix pomatia lectin and wheat germ agglutinin indicated that AL cisternae, similar to cis-Golgi membranes, contain intermediate, but not terminal, forms of glycoconjugates. Taken together, these results suggest that in this cell-virus system, AL function as a viral glycoprotein storage compartment and as a putative site of O-glycosylation.     

Expression of the selectable marker gene bsrm in BALB/MK cells induces apoptosis by overproduction of hydrogen peroxide.

Transduction of the retroviral vector LBmSN, which expresses the blasticidin S resistance gene bsrm in the murine keratinocyte cell line BALB/MK, induces death in these cells. Cell death is caused by a factor called DOKEB (death factor obtained from keratinocytes expressing bsrm), which is released before the cells' death. In this report we describe and discuss the purification and characterization of DOKEB. Our results were as follows. (i) The 5-day-old medium from the modified BALB/MK cells with LBmSN was used for purification and characterization by filtration and chromatography: DOKEB was a stable and highly hydrophilic compound, with a molecular mass less than that of 1 amino acid. (ii) The conditioned medium containing DOKEB was reactive against thiobarbituric acid and dichlorofluorescein diacetate. (iii) DOKEB activity was neutralized by the incubation of the conditioned medium with catalase. Therefore, our conclusion is that the BALB/MK cells expressing bsrm produce a large amount of hydrogen peroxide, which catalyzes the process of apoptosis of those cells.     

Comparison of different vitrification protocols on viability after transfer of ovine blastocysts in vitro produced and in vivo derived

We compare different vitrification protocols on the pregnancy and lambing rate of in vitro produced (IVP) and in vivo derived (IVD) ovine embryos. Ovine blastocysts were produced by in vitro maturation, fertilization and culture of oocytes collected from slaughtered ewes or superovulated and inseminated animals. Embryos were cryopreserved after exposure at room temperature either for 5 min in 10% glycerol (G), then for 5 min in 10% G + 20% ethylene glycol (EG), then for 30 s in 25% G + 25% EG (glycerol group), or for 3 min in 10% EG + 10% dimethyl sulphoxide (DMSO), then for 30s in 20% EG + 20% DMSO + 0.3 M sucrose (DMSO group). One group of in vitro produced embryos was cryopreserved similarly to the DMSO group, but with 0.75 M sucrose added to the vitrification solution (DMSO 0.75 group). Glycerol group embryos were then loaded into French straws or open pulled Straws (OPS) while the DMSO group embryos were all loaded into OPS and directly plunged into liquid nitrogen. Embryos were warmed with either a one step or three step process. In the one step process, embryos were placed in 0.5 M sucrose. The three-step process was a serial dilution in 0.5, 0.25 and 0.125 M sucrose. The embryos of DMSO 0.75 group were warmed directly by plunging them into tissue culture medium-199 (TCM-199) + 20% foetal bovine serum (FBS) in the absence of sucrose (direct dilution). Following these manipulations, the embryos were transferred in pairs into synchronised recipient ewes and allowed to go to term. The pregnancy and the lambing rate within each group of IVP and IVD embryos indicated that there was no statistical difference among the vitrification protocols.     

Trypanosoma cruzi heat-shock protein-70 kDa,alone or fused to the parasite KMP11 antigen,induces functional maturation of murine dendritic cells

We analyse the effect of Trypanosoma cruzi heat-shock protein-70 (HSP70) on the maturation of murine dendritic cells (DC)generated from bone marrow precursor cells. The results obtained show that HSP70, both alone and fused to the KMP11 antigen, as well as a HSP70 fragment, is capable of maturing murine DC. Mature DC have enhanced expression of IL12, TNF-alpha cytokines, costimulation molecules and activation markers, showing a clear increase in the allostimulatory capacity. These findings suggest that T. cruzi HSP70 may be a very useful vehicle for developing DC-based immunoprophylaxis and therapy against infections.