Mitogen-activated protein kinase phosphatase 1 activity is necessary for oxidized phospholipids to induce monocyte chemotactic activity in human aortic endothelial cells

Entrapment and oxidation of low density lipoproteins (LDL) in the sub-endothelial space is a key process in the initiation of atherosclerotic lesion development. Functional changes induced by oxidized lipids in endothelial cells are early events in the pathogenesis of atherosclerosis. Oxidized-l-alpha-1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (ox-PAPC), a major component of minimally modified/oxidized-LDL (MM-LDL) mimics the biological activities assigned to MM-LDL both in vitro in a co-culture model as well as in vivo in mice. We hypothesized that ox-PAPC initiates gene expression changes in endothelial cells that result in enhanced endothelial/monocyte interactions. To analyze the gene expression changes that oxidized lipids induce in endothelial cells, we used a suppression subtractive hybridization procedure to compare mRNA from PAPC-treated human aortic endothelial cells (HAEC) with that of ox-PAPC-treated cells. We report here the identification of a gene, mitogen-activated protein kinase phosphatase 1 (MKP-1), that is rapidly and transiently induced in ox-PAPC-treated HAEC. Inhibition of MKP-1 using either the phosphatase inhibitor sodium orthovanadate or antisense oligonucleotides prevents the accumulation of monocyte chemotactic activity in ox-PAPC-treated HAEC supernatants. Furthermore, we show that decreased monocyte chemotactic activity in HAEC treated with sodium orthovanadate or MKP-1 antisense oligonucleotides is due to decreased MCP-1 protein. Our results implicate a direct role for MKP-1 in ox-PAPC-induced signaling pathways that result in the production of MCP-1 protein by ox-PAPC-treated HAEC.     

Novel reversion reaction of D-arabino-hexose phenylosotriazole. A useful model in natural glycoside and polysaccharide analysis

Treatment of D-arabino-hexose phenylosotriazole with conc. hydrochloric acid afforded a new type of alpha- and beta-glycosides of D-erythrose formed by reaction of the 3,6-anhydro derivative with the in situ formed 2-phenyl-4-(formylmethyl)- 1,2,3-triazole.     

Ischemic injury to mitochondrial electron transport in the aging heart: damage to the iron-sulfur protein subunit of electron transport complex III

The aging heart sustains greater injury during ischemia and reperfusion compared to adult hearts. Aging decreases oxidative function in interfibrillar mitochondria (IFM) that reside among the myofibers, while subsarcolemmal mitochondria (SSM), located beneath the plasma membrane, remain unaltered. Aging decreases complex III activity selectively in IFM via alteration of the cytochrome c binding site. With 25 min of global ischemia, complex III activity decreases in SSM and further decreases in IFM in the aging heart. Ischemia leads to a marked decrease in the electron paramagnetic resonance signal of the iron-sulfur protein (ISP) in both SSM and IFM, despite a preserved content of ISP peptide. Thus, ischemia results in a functional decrease in the iron-sulfur center in ISP without subunit peptide loss. In the aging heart, at the onset of reperfusion, IFM contain two tandem defects in the path of electron flow through complex III, providing a likely mechanism for enhanced oxidant production and reperfusion damage.     

Immune regulation of ovarian function in buffaloes (Bubalus bubalus)

We studied the infiltration of different subsets of immune system cells in the ovarian parenchyma of Egyptian buffaloes during follicular and luteal phases of the estrous cycle. All subsets of leukocytes infiltrated significantly more into corpora lutea (CL) than into Graafian follicles (GF) (P < 0.01) except for plasma cells that were abundant in the GF but not observed in the CL. The number of macrophages, lymphocytes, neutrophils and eosinophils were significantly greater in mature CL than in corpora hemorrhagica (CH) or regressing CL. Moreover, the regressing CL showed significantly more macrophages, lymphocytes and neutrophils than the CH. Large antral follicles were infiltrated with larger number of leukocytes than growing preantral atretic follicles. Macrophages and neutrophils observed in large antral follicles were significantly more abundant in the theca externa than the theca interna (P < 0.01). Only plasma cells were significantly greater in number in the theca intema (P < 0.01). Leukocytes infiltrated significantly more into large mature follicles than large, growing, preantral atretic follicles (P < 0.01). Results of this study reveal the calling of leukocytes in a significant numbers inside the ovarian tissue of buffaloes around the time of ovulation and at luteolysis. It is possible that leukocytes with their powerful bioactive cytokines (IL-1, TNFalpha, GM-CSF, and INF-gamma) may assist in ovarian functions such as ovulation and luteolysis.     

A role for Drosophila SMC4 in the resolution of sister chromatids in mitosis

BACKGROUND: Faithful segregation of the genome during mitosis requires interphase chromatin to be condensed into well-defined chromosomes. Chromosome condensation involves a multiprotein complex known as condensin that associates with chromatin early in prophase. Until now, genetic analysis of SMC subunits of the condensin complex in higher eukaryotic cells has not been performed, and consequently the detailed contribution of different subunits to the formation of mitotic chromosome morphology is poorly understood. RESULTS: We show that the SMC4 subunit of condensin is encoded by the essential gluon locus in Drosophila. DmSMC4 contains all the conserved domains present in other members of the structural-maintenance-of-chromosomes protein family. DmSMC4 is both nuclear and cytoplasmic during interphase, concentrates on chromatin during prophase, and localizes to the axial chromosome core at metaphase and anaphase. During decondensation in telophase, most of the DmSMC4 leaves the chromosomes. An examination of gluon mutations indicates that SMC4 is required for chromosome condensation and segregation during different developmental stages. A detailed analysis of mitotic chromosome structure in mutant cells indicates that although the longitudinal axis can be shortened normally, sister chromatid resolution is strikingly disrupted. This phenotype then leads to severe chromosome segregation defects, chromosome breakage, and apoptosis. CONCLUSIONS: Our results demonstrate that SMC4 is critically important for the resolution of sister chromatids during mitosis prior to anaphase onset.     

Molecular typing of Salmonella weltevreden and Salmonella chincol by pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR)

Genomic DNA of Salmonella weltevreden (10 isolates from poultry, two isolates each from raw vegetables and river water) and S. chincol (15 isolates from poultry) were characterized by pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) analysis. These isolates originated from a single location in Kajang, Selangor. The results of the PFGE and ERIC-PCR were analysed and comparisons were made using GelCompar software. ERIC-PCR with primers ERIC1R and ERIC2 discriminated the S. weltevreden into five clusters and two single isolates and S. chincol into two clusters and two single isolates at a similarity level of 80%, respectively. PFGE produced a single cluster and eight single isolates for S. weltevreden, and one cluster and 11 single isolates for S. chincol at a similarity level of 80% after digestion with the restriction enzyme XbaI, respectively. These results demonstrate that both PFGE and ERIC-PCR are suitable tools for molecular typing of the isolates examined. This revised version was published online in July 2006 with corrections to the Cover Date.     

Determining suitable grazing time for Puccinella distans Parl. based on its phenology in West Azerbaijan Province of Iran

Studying the phenology, which is an important issue of plants, can be used for determining the best time of all kinds of utilizations, and also conservation and stability of plants’ growth and breeding will result. Therefore, this study was performed in Tezkharab rangelands, where Puccinella distans is an important vegetative element that is consumed by livestock, to determine the suitable grazing time for this plant based on its phenology, for about a 4-year period (2007–2010). For this purpose, plant phenology and changes in its growth characteristics were investigated weekly. Moreover, during this period, all phenological stages were adjusted to the monthly precipitation and temperature. The results indicated that the time of phenological stages had fluctuations which were related to environmental conditions. The best time to start grazing is early May and the best time for collecting the seeds of this species is late July to early August.     

Purkinje Cell Compartmentation in the Cerebellum of the Lysosomal Acid Phosphatase 2 Mutant Mouse (Nax - Naked-Ataxia Mutant Mouse)

The Acp2 gene encodes the beta subunit of lysosomal acid phosphatase, which is an isoenzyme that hydrolyzes orthophosphoric monoesters. In mice, a spontaneous mutation in Acp2 results in severe cerebellar defects. These include a reduced size, abnormal lobulation, and an apparent anterior cerebellar disorder with an absent or hypoplastic vermis. Based on differential gene expression in the cerebellum, the mouse cerebellar cortex can normally be compartmentalized anteroposteriorly into four transverse zones and mediolaterally into parasagittal stripes. In this study, immunohistochemistry was performed using various Purkinje cell compartmentation markers to examine their expression patterns in the Acp2 mutant. Despite the abnormal lobulation and anterior cerebellar defects, zebrin II and PLCβ4 showed similar expression patterns in the nax mutant and wild type cerebellum. However, fewer stripes were found in the anterior zone of the nax mutant, which could be due to a lack of Purkinje cells or altered expression of the stripe markers. HSP25 expression was uniform in the central zone of the nax mutant cerebellum at around postnatal day (P) 18–19, suggesting that HSP25 immunonegative Purkinje cells are absent or delayed in stripe pattern expression compared to the wild type. HSP25 expression became heterogeneous around P22–23, with twice the number of parasagittal stripes in the nax mutant compared to the wild type. Aside from reduced size and cortical disorganization, both the posterior zone and nodular zone in the nax mutant appeared less abnormal than the rest of the cerebellum. From these results, it is evident that the anterior zone of the nax mutant cerebellum is the most severely affected, and this extends beyond the primary fissure into the rostral central zone/vermis. This suggests that ACP2 has critical roles in the development of the anterior cerebellum and it may regulate anterior and central zone compartmentation.