Identification of transcripts from a subtraction library which might be responsible for the mild phenotype in an intrafamilially variable course of Duchenne muscular dystrophy

While frame-shift mutations are usually found in Duchenne muscular dystrophy (DMD), in-frame mutations are associated with the less severe phenotype of Becker's muscular dystrophy. Exceptions have been reported in both directions suggesting the existence of modifying genes, which might be helpful for innovation of new therapeutic strategies. We report on the very rare case of an intrafamilially different course of DMD, with the younger brother being far less affected than the older one when compared at the same age. In this context, we constructed a subtraction library enriched for transcripts over-expressed in the patient with the milder phenotype. Twelve random clones were sequenced, followed by database analysis. Six of them, casein kinase 1 alpha 1, RAP2B, dynactin 3 light chain, core binding factor beta, myosin light polypeptide 2 and one hypothetical gene, were further analysed by real-time RT-PCR. All these genes were over-expressed 3-20 times in the less affected patient compared with the more severely affected one. Casein kinase 1 and the hypothetical gene showed even a slightly higher expression than the control. Up-regulation of myosin light polypeptide 2, one of the most sensitive markers of muscle fibre regeneration, obviously reflects the milder phenotype. Casein kinase 1, dynactin and core binding factor are supposed to be involved in cell cycle pathways. RAP is a component of the signalling network which controls fundamental cellular processes such as proliferation and differentiation. All four might be interesting candidates for a therapeutic approach to diminish progression of dystrophy in DMD.

Transverse-momentum spectra in Au+Au and d+Au collisions at sqrt[s(NN)]=200 GeV and the pseudorapidity dependence of high-p(T) suppression

We present spectra of charged hadrons from Au+Au and d+Au collisions at sqrt[s(NN)]=200 GeV measured with the BRAHMS experiment at RHIC. The spectra for different collision centralities are compared to spectra from p+(-)p collisions at the same energy scaled by the number of binary collisions. The resulting ratios (nuclear modification factors) for central Au+Au collisions at eta=0 and eta=2.2 evidence a strong suppression in the high p(T) region (>2 GeV/c). In contrast, the d+Au nuclear modification factor (at eta=0) exhibits an enhancement of the high p(T) yields. These measurements indicate a high energy loss of the high p(T) particles in the medium created in the central Au+Au collisions. The lack of suppression in d+Au collisions makes it unlikely that initial state effects can explain the suppression in the central Au+Au collisions.

Measurement of long-range repulsive forces between charged particles at an oil-water interface

Using a laser tweezers method, we have determined the long-range repulsive force as a function of separation between two charged, spherical polystyrene particles (2.7 microm diameter) present at a nonpolar oil-water interface. At large separations (6 to 12 microm between particle centers) the force is found to decay with distance to the power -4 and is insensitive to the ionic strength of the aqueous phase. The results are consistent with a model in which the repulsion arises primarily from the presence of a very small residual electric charge at the particle-oil interface. This charge corresponds to a fractional dissociation of the total ionizable (sulfate) groups present at the particle-oil surface of approximately 3 x 10(-4).

[Radioprotective effectiveness of amifostine on the salivary glands of the rat during fractionated irradiation]

BACKGROUND

The aim of this study was to evaluate the cytoprotective potency of amifostine during a fractioned irradiation of salivary glands but also on the tumor response of rhabdomyosarcomas R1H in rats.

METHOD

The head-neck-area of male WAG/RijH rats and the tumor in the flank were irradiated with 60Co-gamma-rays (60 Gy/30 f/6 weeks). Amifostine (250 mg/m2) was applicated 15 min before irradiation. The control group was treated with an equal volume of physiologic sodium chloride. The salivary glands were exstirpated and examined histopathologically. Tumour volume was measured, the body-weight of rats determined.

RESULTS

A dose dependent radiosialadenitis developed in all salivary glands. Amifostine had no influence on the response of R1H tumours to radiation. The animal weight loss in the amifostine group was higher as compared to control group.

CONCLUSIONS

No cytoprotective effects on acute toxicity of salivary glands of rats could be detected under irradiation with synchronous application of amifostine. In addition, no effects on tumor response were observed. The general animal constitution decreased by additional medication of amifostine.

Reactivity of the inversely polarized phosphaalkenes RP=C(NMe2)2 (R = tBu, Me3Si, H) towards arylcarbene complexes [(CO)5M=C(oEt)Ar] (Ar= Ph, M = Cr, W; Ar = 2-MeC6H4, 2-MeOC6H4, M = W)

The reaction of the arylated Fischer carbene complexes [(CO)5M=C(OEt)Ar] (Ar=Ph; M = Cr, W; 2-MeC6H4; 2-MeOC6H; M = W) with the phosphaalkenes RP=C(NMe2), (R=tBu, SiMe3) afforded the novel phosphaalkene complexes [[RP=C(OEt)Ar]M(CO)5] in addition to the compounds [(RP=C(NMe2)2]M(CO)5]. Only in the case of the R = SiMe3 (E/Z) mixtures of the metathesis products were obtained. The bis(dimethylamino)methylene unit of the phosphaalkene precursor was incorporated in olefins of the type (Me2N)2C=C(OEt)(Ar). Treatment of [(CO)5W=C(OEt)(2-MeOC6H4)] with HP=C(NMe2)2 gave rise to the formation of an E/Z mixture of [[(Me2N)2CH-P=C(OEt)(2-MeOC6H4)]W(CO)5] the organophosphorus ligand of which formally results from a combination of the carbene ligand and the phosphanediyl [P-CH(NMe2)2]. The reactions reported here strongly depend on an inverse distribution of alpha-electron density in the phosphaalkene precursors (Pdelta Cdelta+), which renders these molecules powerfu] nucleophiles.

Novel heterocyclic inhibitors of matrix metalloproteinases: three 6H-1,3,4-thiadiazines

The title compounds, (2S)-N-[5-(4-chlorophenyl)-2,3-dihydro-6H-1,3,4-thiadiazin-2-ylidene]-2-[(phenylsulfonyl)amino]propanamide, C18H17ClN4O3S2, (I), (2R)-N-[5-(4-fluorophenyl)-6H-1,3,4-thiadiazin-2-yl]-2-[(phenylsulfonyl)amino]propanamide, C18H17FN4O3S2, (II), and (2S)-N-[5-(5-chloro-2-thienyl)-6H-1,3,4-thiadiazin-2-yl]-2-[(phenylsulfonyl)amino]propanamide, C16H15ClN4O3S3, (III), are potent inhibitors of matrix metalloproteinases. In all three compounds, the thiadiazine ring adopts a screw-boat conformation. The molecules of compound (I) show a short intramolecular N(Ala)-H...N(exo) hydrogen bond [N...N 2.661 (3) A] and are linked into a chain along the c axis by N(endo)-H...S(endo) and N(endo)-H...O(Ala) hydrogen bonds [N...S 3.236 (3) and N...O 3.375 (3) A] between neighbouring molecules. In compound (II), the molecules are connected antiparallel into a chain along the a axis by N(exo)-H...O(Ala) and N(Ala)-H...N(endo) hydrogen bonds [N...O 2.907 (6) and N...N 2.911 (6) A]. The molecules of compound (III) are dimerized antiparallel through N(exo)-H...N(endo) hydrogen bonds [N...N 2.956 (7) and 2.983 (7) A]. The different hydrogen-bonding patterns can be explained by an amido-imino tautomerism (prototropic shift) shown by different bond lengths within the 6H-1,3,4-thiadiazine moiety.

Endotoxin-induced lung inflammation is independent of the complement membrane attack complex

Several products of the activated complement system are known to modulate endothelial cell function in vitro. It has been shown that the membrane attack complex (MAC) (C5b-C9) can enhance tumor necrosis factor alpha (TNF-alpha)-induced expression of P- and E-selectin and intercellular adhesion molecule type 1 in cell cultures of human umbilical vein endothelial cells. In the present study the potential role of this synegism for lung injury during endotoxin-mediated septic shock in vivo was examined using a model of C6-deficient PVG (C-) (RT1(C)) rats and the congenic PVG (C+) (RT1(C)) strain. Following administration of a high (5 mg/kg) or low (0.5 mg/kg) dose of lipopolysaccharide (LPS) (Escherichia coli O55:B5), we determined the expression of cytokines, chemokines, and adhesion molecules as well as the recruitment of leukocytes in the lung. Challenge with intraperitoneal i.p. injections of LPS resulted in a strong induction of TNF-alpha, interleukin-1alpha/beta, cytokine-induced neutrophil chemoattractant, interferon-inducible protein 10, macrophage inflammatory proteins 1alpha and 2, macrophage chemotactic protein 1, and P-selectin. However, there were no significant differences between PVG (C-) and PVG (C+) rats. Immunoperoxidase staining showed a similar increase of lung infiltration by CD11b/c(+) leukocytes in both rat strains. We therefore conclude that the described synergism between TNF-alpha and the MAC of the complement system on the induction of endothelial adhesion molecules is dispensable for inflammatory processes during endotoxin-mediated septic shock in vivo.

Casein kinase 2 binds and phosphorylates the nucleosome assembly protein-1 (NAP1) in Drosophila melanogaster

The nucleosome assembly protein-1 (NAP1) was originally identified in HeLa cells as a factor facilitating the in vitro assembly of nucleosomes. However, in yeast cells NAP1 is required in the control of mitotic events induced by the Clb2/p34(CDC28). Here, we show that Drosophila NAP1 is a phosphoprotein that is associated with a kinase able to phosphorylate NAP1. By using an in-gel kinase assay we found that this kinase displays a molecular mass of 38 kDa. Following purification and peptide microsequencing, we identified the kinase phosphorylating NAP1 as the alpha subunit of casein kinase 2 (CK2). With the help of a series of NAP1 segments and synthetic peptides, we assigned the CK2 phosphorylation sites to residues Ser118, Thr120, and Ser284. Interestingly, Ser118 and Thr120 are located within a PEST domain, while Ser284 is adjacent to the nuclear localization signal. Substitution of the identified phosphoresidues by alanine was found to reduce considerably the ability of CK2 to phosphorylate NAP1. The enhanced ability of CK2 to phosphorylate phosphatase-treated NAP1 extracted from Drosophila embryos and the similar tryptic phospho-peptide pattern of in vivo labelled NAP1 and in vitro labelled NAP1 with CK2 indicate that NAP1 is a natural substrate of CK2. Further analysis revealed that both CK2alpha and beta subunits are associated with NAP1 but we found that only the catalytic alpha subunit establishes direct contact with NAP1 on two distinct domains of this protein. The location of CK2 phosphorylation sites in NAP1 suggests that their phosphorylation can contribute to a PEST-mediated protein degradation of NAP1 and the translocation of NAP1 between cytoplasm and nucleus.

Mechanisms of acute inflammatory lung injury induced by abdominal sepsis

Sequestration of neutrophils and release of histotoxic mediators are considered important for the development of pathologic alterations of the lung defined as adult respiratory distress syndrome. Mechanisms of inflammatory lung injury caused by abdominal sepsis were investigated using the colon ascendens stent peritonitis (CASP) model that closely mimics the human disease. In the CASP model, a continuous leakage of intraluminal bacteria into the peritoneal cavity is induced by implantation of a stent in the ascending colon, generating a septic focus. In contrast to the cecal ligation and puncture model of peritonitis, survival of mice following CASP surgery is dependent on IFN-gamma, but independent of tumor necrosis factor (TNF). Here we show that the systemic inflammation induced by CASP surgery results in a rapid and profound increase of lung vascular permeability that was associated with the activation and recruitment of neutrophils to the lung. Activation of circulating granulocytes was characterized by increased production of serine proteinases and reactive oxygen metabolites, as well as elevated expression of cell surface Mac-1. Expression of MIP-2, KC, MIP-1alpha and E-selectin mRNA in lung was strongly increased within 3 h following CASP surgery, whereas up-regulation of IP-10, MCP-1 and P-selectin was delayed. In contrast, induction of RANTES, LIX, ICAM-1 and VCAM-1 mRNA was weak or not detectable after CASP surgery. Importantly, recruitment of leukocytes to the lung was normal in lipopolysaccharide-resistant mice, and was not affected by antibody neutralization of TNF or the chemokines MIP-2 and KC.

Treatment with dexamethasone alters yawning behavior induced by cholinergic but not dopaminergic agonist

Because stressful manipulations have been reported to modify drug-induced yawning, the present study investigated the effects of single and repeated treatment with a synthetic glucocorticoid, dexamethasone (DEXA) on apomorphine- and pilocarpine-induced yawning in male rats. Neither single nor repeated treatment with DEXA altered apomorphine-induced yawning. Single administration of DEXA, however, resulted in an increased number of yawns induced by pilocarpine. Conversely, repeated administration of DEXA led to a decreased number of yawns induced by pilocarpine. In conclusion, the present findings show that dopaminergic and cholinergic are distinctly altered by DEXA, in terms of yawning behavior when animals received DEXA.