Synthesis, liposomal preparation, and in vitro toxicity of two novel dodecaborate cluster lipids for boron neutron capture therapy

A new class of lipids, containing the closo-dodecaborate cluster, has been synthesized. Two lipids, S-(N, N-(2-dimyristoyloxyethyl)acetamido)thioundecahydro-closo-dodecaborate (2-) (B-6-14) and S-(N, N-(2-dipalmitoyloxyethyl)acetamido)thioundecahydro-closo-dodecaborate (2-) (B-6-16) are described. Both of them have a double-tailed lipophilic part and a headgroup carrying two negative charges. Differential scanning calorimetry shows that B-6-14 and B-6-16 bilayers have main phase transition temperatures of 18.8 and 37.9 degrees C, respectively. Above the transition temperature of 18.8 degrees C, B-6-14 can form liposomal vesicles, representing the first boron-containing lipid with this capability. Upon cooling below the transition temperature, stiff bilayers are formed. When incorporated into liposomal formulations with equimolar amounts of distearoyl phosphatidylcholine (DSPC) and cholesterol, stable liposomes are obtained. The zeta-potential measurements indicate that both B-6-14- and B-6-16-containing vesicles are negatively charged, with the most negative potential described of any liposome so far. The liposomes are of high potential value as transporters of boron to tumor cells in treatments based on boron neutron capture therapy (BNCT). Liposomes prepared from B-6-14 were slightly less toxic in V79 Chinese hamster cells (IC50 5.6 mM) than unformulated Na2B12H11SH (IC50 3.9 mM), while liposomes prepared from B-6-16 were not toxic even at 30 mM.     

Allicin and derivates are cysteine protease inhibitors with antiparasitic activity

Allicin and derivatives thereof inhibit the CAC1 cysteine proteases falcipain 2, rhodesain, cathepsin B and L in the low micromolar range. The structure–activity relationship revealed that only derivatives with primary carbon atom in vicinity to the thiosulfinate sulfur atom attacked by the active-site Cys residue are active against the target enzymes. Some compounds also show potent antiparasitic activity against Plasmodium falciparum and Trypanosoma brucei brucei.     

Ultrasonographic characterization of the ovaries and the uterus in prepubertal and pubertal gilts

In two experiments (EXP), 44 and 52 crossbred gilts (mean age+/-S.D. and weight+/-S.D.: 204+/-22 and 203+/-9 days, 114+/-13 and 127+/-12 kg, respectively, in EXP 1 and 2) from four farms were examined by means of transcutaneous ultrasonography (US) to define the characteristics of the ovaries and the uterus (echotexture, size) and to investigate the appropriateness of US to determine sexual maturity. Gilts were judged as prepubertal [PRE; follicles 2-5 mm (F2-5) only] or pubertal [PUB; F7-8, corpora lutea (CL), corpora haemorrhagica (CH)] at the first (PUB-1; EXP 1) or a subsequent estrous cycle [PUB-2; additionally corpora albicantia (CA); EXP 1] by US, and results were verified by postmortem examination (EXP 1), or progesterone analysis and detection of estrous signs (EXP 2). Accuracy of US was 100% for PRE and PUB (both EXP) and 77.3% for PUB-1 and PUB-2 (EXP 1). PRE and PUB with CL/CH had uteri of homogeneous, PUB with F7-8 of heterogeneous echotexture. The size was expressed as the mean sectional area (SAsono) of 2-5 cross-sections of the uterine horns (calculated by multiplication of 1/2 the maximum x the minimum dimension of the cross-sections x pi). SAsono corresponded with the sectional area of postmortem dissected transverse uterine segments relatively with r=0.92 (P<0.0001; EXP 1). Mean SAsono (both EXP) and mean uterine weight (EXP 1) were PRE相似文献   

miR-155 Inhibition Sensitizes CD4+ Th Cells for TREG Mediated Suppression

Background

In humans and mice naturally occurring CD4⁺CD25⁺ regulatory T cells (nTregs) are a thymus-derived subset of T cells, crucial for the maintenance of peripheral tolerance by controlling not only potentially autoreactive T cells but virtually all cells of the adaptive and innate immune system. Recent work using Dicer-deficient mice irrevocably demonstrated the importance of miRNAs for nTreg cell-mediated tolerance.

Principal Findings

DNA-Microarray analyses of human as well as murine conventional CD4⁺ Th cells and nTregs revealed a strong up-regulation of mature miR-155 (microRNA-155) upon activation in both populations. Studying miR-155 expression in FoxP3-deficient scurfy mice and performing FoxP3 ChIP-Seq experiments using activated human T lymphocytes, we show that the expression and maturation of miR-155 seem to be not necessarily regulated by FoxP3. In order to address the functional relevance of elevated miR-155 levels, we transfected miR-155 inhibitors or mature miR-155 RNAs into freshly-isolated human and mouse primary CD4⁺ Th cells and nTregs and investigated the resulting phenotype in nTreg suppression assays. Whereas miR-155 inhibition in conventional CD4⁺ Th cells strengthened nTreg cell-mediated suppression, overexpression of mature miR-155 rendered these cells unresponsive to nTreg cell-mediated suppression.

Conclusion

Investigation of FoxP3 downstream targets, certainly of bound and regulated miRNAs revealed the associated function between the master regulator FoxP3 and miRNAs as regulators itself. miR-155 is shown to be crucially involved in nTreg cell mediated tolerance by regulating the susceptibility of conventional human as well as murine CD4⁺ Th cells to nTreg cell-mediated suppression.     

Hetero-oligomerization of reggie-1/flotillin-2 and reggie-2/flotillin-1 is required for their endocytosis

Reggie-1/flotillin-2 and reggie-2/flotillin-1 are membrane raft associated proteins which have been implicated in growth factor signaling, phagocytosis, regulation of actin cytoskeleton and membrane trafficking. Membrane and raft association of reggies is mediated by myristoylation, palmitoylation and oligomerization. We have shown that upon EGF stimulation of cells, reggie-1 is tyrosine phosphorylated by Src kinase and endocytosed into late endosomes. Here we have analyzed the mechanism of the EGF-stimulated endocytosis of reggies in more detail and show that the Src-mediated phosphorylation of reggie-1 is not the driving force for endocytosis. However, hetero-oligomerization with reggie-2 is necessary for the translocation of reggie-1, which does not take place in the absence of reggie-2. In addition, the Y163F mutant of reggie-1, which is not capable of undergoing endocytosis, oligomerizes poorly with reggie-2. EGF stimulation results in changes in the size but not in the stoichiometry of the reggie hetero-oligomers, and reggie-1 oligomer size is decreased by knockdown of reggie-2. Based on our findings, we propose a model according to which reggie hetero-oligomers are dynamic, and changes in the size of the hetero-oligomers result in endocytosis of the complex from the plasma membrane.     

Complete genome sequence of Arcanobacterium haemolyticum type strain (11018)

Arcanobacterium haemolyticum (ex MacLean et al. 1946) Collins et al. 1983 is the type species of the genus Arcanobacterium, which belongs to the family Actinomycetaceae. The strain is of interest because it is an obligate parasite of the pharynx of humans and farm animal; occasionally, it causes pharyngeal or skin lesions. It is a Gram-positive, nonmotile and non-sporulating bacterium. The strain described in this study was isolated from infections amongst American soldiers of certain islands of the North and West Pacific. This is the first completed sequence of a member of the genus Arcanobacterium and the ninth type strain genome from the family Actinomycetaceae. The 1,986,154 bp long genome with its 1,821 protein-coding and 64 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.     

The DEK protein--an abundant and ubiquitous constituent of mammalian chromatin

The protein DEK is an abundant and ubiquitous chromatin protein in multicellular organisms (not in yeast). It is expressed in more than a million copies/nucleus of rapidly proliferating mammalian cells. DEK has two DNA binding modules of which one includes a SAP box, a sequence motif that DEK shares with a number of other chromatin proteins. DEK has no apparent affinity to specific DNA sequences, but preferentially binds to superhelical and cruciform DNA, and induces positive supercoils into closed circular DNA. The available evidence strongly suggests that DEK could function as an architectural protein in chromatin comparable to the better known classic architectural chromatin proteins, the high-mobility group or HMG proteins.     

Attachment style in parents of children with chronic gastrointestinal disease

Attachment is a point of interest in psychosomatic research since it influences a wide array of biopsychosocial phenomena. Data from literature highlights the role of this concept in the context of Inflammatory Bowel disease (IBD), still, there is a lack of data regarding attachment among parents of children with chronic gastrointestinal diseases. The main hypothesis for the current study is that parents of children with IBD will have a more insecure attachment than parents of children with celiac disease (CD) and parents of healthy children. The second hypothesis is that insecure attachment among parents of sick children will be associated with lower parental quality of life (QoL). 46 parents of children with IBD, 42 parents of children with CD and 43 parents of healthy children completed the validated modification of the Brennan's Experiences in Close Relationship Inventory. Results were categorized as secure and insecure attachment. In order to assess parental QoL, the WHOQOL-BREF questionnaire was used. The Total QoL was calculated as a sum of all domain items. Secure attachment was found in 45.7% parents of children with IBD, in 35.7% parents of children with CD and in 32.6% parents of healthy children. Surprisingly, the lowest rate of secure attachment was found in parents of healthy children. However, significant differences among groups do not exist. For all groups of parents the attachment style is associated with Total QoL, although only among parents of children with IBD, the secure attachment independently and significantly predicts higher parental Total QoL. According to results, we might say that parental attachment style does not have a role that exclusively belongs in the context of paediatric chronic gastrointestinal diseases. However, parents of children with IBD who have insecure attachment represent target group for psychosocial support in order to improve their QoL.     

ArchbotLit—the archaeobotanical literature database: an update of the search engine for literature on archaeological remains of cultivated plants since 1981

Vegetation History and Archaeobotany - The online Archaeobotanical Literature Database (ArchbotLit) is an important tool for getting targeted access to archaeobotanical publications. It offers the...     

Functional domains of the ubiquitous chromatin protein DEK

DEK was originally described as a proto-oncogene protein and is now known to be a major component of metazoan chromatin. DEK is able to modify the structure of DNA by introducing supercoils. In order to find interaction partners and functional domains of DEK, we performed yeast two-hybrid screens and mutational analyses. Two-hybrid screening yielded C-terminal fragments of DEK, suggesting that DEK is able to multimerize. We could localize the domain to amino acids 270 to 350 and show that multimerization is dependent on phosphorylation by CK2 kinase in vitro. We also found two DNA binding domains of DEK, one on a fragment including amino acids 87 to 187 and containing the SAF-box DNA binding motif, which is located between amino acids 149 and 187. This region is sufficient to introduce supercoils into DNA. The second DNA binding domain is located between amino acids 270 and 350 and thus overlaps the multimerization domain. We show that the two DNA-interacting domains differ in their binding properties and in their abilities to respond to CK2 phosphorylation.