A physical map of the human genome

The human genome is by far the largest genome to be sequenced, and its size and complexity present many challenges for sequence assembly. The International Human Genome Sequencing Consortium constructed a map of the whole genome to enable the selection of clones for sequencing and for the accurate assembly of the genome sequence. Here we report the construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions. We also describe the integration of sequence data with the map.

The c-Src tyrosine kinase regulates signaling of the human DF3/MUC1 carcinoma-associated antigen with GSK3 beta and beta-catenin

The DF3/MUC1 mucin-like glycoprotein is aberrantly overexpressed in most human carcinomas. The cytoplasmic domain of MUC1 interacts with glycogen synthase kinase 3 beta (GSK3 beta) and thereby decreases binding of MUC1 and beta-catenin. The present studies demonstrate that MUC1 associates with the c-Src tyrosine kinase. c-Src phosphorylates the MUC1 cytoplasmic domain at a YEKV motif located between sites involved in interactions with GSK3 beta and beta-catenin. The results demonstrate that the c-Src SH2 domain binds directly to pYEKV and inhibits the interaction between MUC1 and GSK3 beta. Moreover and in contrast to GSK3 beta, in vitro and in vivo studies demonstrate that c-Src-mediated phosphorylation of MUC1 increases binding of MUC1 and beta-catenin. The findings support a novel role for c-Src in regulating interactions of MUC1 with GSK3 beta and beta-catenin.

Knowledge, attitude and practice survey regarding blood donation in a Northwestern Chinese city

Recruitment of low-risk blood donors in developing countries is challenging. We studied the attitudes towards blood donation in several populations in a city in Western China. A survey of knowledge, attitude and practice was performed including 1280 individuals from eight distinct populations in Urumqi, Xinjiang Uyghur Autonomous Region, China. Included were Han Chinese and Uyghur populations of blood donors, non-donors, injection drug users, students and factory workers. Knowledge about blood donation varied between the groups. Factors motivating blood donation included social pressure, desire to know screening results and altruism. Inhibiting factors included fear of contracting an infection and other adverse health effects, including loss of vitality. Misconceptions about the effects of blood donation are widespread, even among educated persons in Urumqi. Fear of acquiring a serious infection may have been increased by the reports of HIV acquisition during plasma donations in China.

Upregulated sirtuin 1 by miRNA-34a is required for smooth muscle cell differentiation from pluripotent stem cells

microRNA-34a (miR-34a) and sirtuin 1 (SirT1) have been extensively studied in tumour biology and longevity/aging, but little is known about their functional roles in smooth muscle cell (SMC) differentiation from pluripotent stem cells. Using well-established SMC differentiation models, we have demonstrated that miR-34a has an important role in SMC differentiation from murine and human embryonic stem cells. Surprisingly, deacetylase sirtuin 1 (SirT1), one of the top predicted targets, was positively regulated by miR-34a during SMC differentiation. Mechanistically, we demonstrated that miR-34a promoted differentiating stem cells' arrest at G0/G1 phase and observed a significantly decreased incorporation of miR-34a and SirT1 RNA into Ago2-RISC complex upon SMC differentiation. Importantly, we have identified SirT1 as a transcriptional activator in the regulation of SMC gene programme. Finally, our data showed that SirT1 modulated the enrichment of H3K9 tri-methylation around the SMC gene-promoter regions. Taken together, our data reveal a specific regulatory pathway that miR-34a positively regulates its target gene SirT1 in a cellular context-dependent and sequence-specific manner and suggest a functional role for this pathway in SMC differentiation from stem cells in vitro and in vivo.

Inhibition of the pro-inflammatory NF-κB pathway by a grape seed and grape marc meal extract in intestinal epithelial cells

In pigs and other monogastric animal, the weaning phase is commonly accompanied by an increased susceptibility to gut disorders such as diarrhoea owing to the induction of an inflammatory process in the intestine during weaning. Given the unfavourable effects of intestinal inflammation on feed consumption, digestive capacity of the intestine and growth of animals, controlling intestinal inflammation is a reasonable approach for the maintenance of performance characteristics of livestock animals. Therefore, this study aimed to study the anti-inflammatory potential of a commercial polyphenol-rich grape seed (GS) and grape marc (GM) meal-based feed additive in a well-established in vitro intestinal epithelium model (polarized Caco-2 cells). The anti-inflammatory potential was evaluated by studying the effect of an ethanolic extract obtained from the GS and GM meal-based feed additive (GSGME) on the pro-inflammatory transcription factor NF-κB, which is considered to play a key role in the induction of weaning-associated intestinal inflammation. The highest non-cytotoxic concentrations of the ethanolic GSGME dose dependently reduced TNFα-induced NF-κB transactivation and decreased TNFα-induced mRNA levels of the NF-κB target genes IL-1β, IL-8, MCP-1 and CXCL1 in Caco-2 intestinal cells (p < 0.05). No effect of the ethanolic GSGME was observed on the cytoprotective Nrf2 pathway in Caco-2 cells as evidenced by an unaltered Nrf2 transactivation and unchanged mRNA levels of Nrf2 target genes, such as GPX-2, NQO1, CYP1A1 and UGT1A1. In conclusion, this study shows that an ethanolic GSGME exerts anti-inflammatory effects in intestinal cells under in vitro conditions. Thus, polyphenol-rich GSGM meal-based feed additives may be useful for the inhibition or prevention of inflammatory processes in the intestine of livestock animals, in particular during states with inappropriate NF-κB activation in the intestinal tissue, such as the weaning phase. Future studies are warranted to prove the in vivo anti-inflammatory potential of GSGM meal-based feed additives.

Rapamycin suppresses angiogenesis and lymphangiogenesis in melanoma by downregulating VEGF-A/VEGFR-2 and VEGF-C/VEGFR-3 expression

Background: Cutaneous melanoma is a highly malignant tumor which tends to metastasize in the early stage and leads to poor prognosis. Hematogenous and lymphatic metastasis are common in the dissemination of melanoma. Rapamycin, an mTOR inhibitor, was reported to have anti-angiogenic and anti-lymphangiogenic properties.

Aim: The aim of this study was to investigate if rapamycin can inhibit the formation of blood vessels and lymphatic vessels in melanoma.

Methods: A melanoma xenograft model was generated by subcutaneously transplanting A375 human melanoma cells into the back of immunodeficient mice. Two weeks after cell transplantation, rapamycin was injected intraperitoneally every other day seven times. Then, tumors were harvested. Hematoxylin-eosin (H-E) staining, immunohistochemical staining, Western blot, and quantitative PCR were performed to observe the pathological structure of the tumor, the distribution of blood vessels and lymphatic vessels, and the expression of mTOR signal pathway, VEGF-A/VEGFR-2, and VEGF-C/VEGFR-3.

Results: The results showed that CD34(+) blood vessels and LYVE-1(+) lymphatic vessels decreased in the peritumor and intratumor region in rapamycin-treated tumors. Expression of p-4EBP1 and p-S6K1 proteins was downregulated. Expression of both proteins and mRNAs of VEGF-A/VEGFR-2 and VEGF-C/VEGFR-3 was downregulated.

Conclusion: In conclusion, rapamycin suppresses angiogenesis and lymphangiogenesis in melanoma by blocking the mTOR signal pathway and subsequently downregulating the expression of VEGF-A/VEGFR-2 and VEGF-C/VEGFR-3. Therefore, targeted therapy via mTOR signal pathway may control the hematogenous and lymphatic metastasis of melanoma, and even prolong patients’ survival time.

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Isolation and characterization of glycoproteins from canine tracheal mucus

Three homogeneous glycoproteins were isolated from reduced and S-carboxy-methylated canine tracheal pouch mucus by gel filtration and ion-exchange chromatography. Initial fractionation was carried out on Sephadex G-200; chromatography of the excluded Sephadex G-200 fraction on Bio-Gel A-15 m yielded two high molecular weight glycoprotein fractions. Following rechromatography on the same column, the main fraction behaved as an electrophoretically homogeneous high molecular weight (581 600) glycoprotein, with a high carbohydrate content (80%) and a single amino-terminal amino acid (arginine). Ion-exchange chromatography (DEAE-cellulose) of the included Sephadex G-200 fraction yielded two electrophoretically homogeneous glycoproteins of lower molecular weight (20 800 and 24 600, respectively). A single amino-terminal amino acid, glycine and alanine, respectively, was detected for each glycoprotein. Chemical analysis of these three glycoproteins revealed the presence of fucose, galactose, N-acetylgalactosamine, N-acetylglucosamine, N-acetylneuraminic acid and sulfate monoester. The high molecular weight glycoprotein had a higher hexose, sialic acid and sulfate content, per mg of protein, than the low molecular weight glycoproteins. The results of the alkaline borohydride treatment indicated that the majority of the carbohydrate chains of these glycoproteins are linked to the protein core through O-glycosidic bonds involving N-acetylgalactosamine and serine or threonine.

Altered GLUT1 and GLUT3 gene expression and subcellular redistribution of GLUT4: protein in muscle from patients with acanthosis nigricans and severe insulin resistance

Multiple isoforms of glucose transporters are found in muscle, the tissue that normally accounts for 85% of insulin-stimulated glucose uptake. Glucose uptake into muscle cells in the fasting state is mediated primarily by GLUT1 and GLUT3 glucose transporters, whereas postprandial (insulin-stimulated) and exercise-related increments in muscle glucose uptake are mediated primarily by GLUT4. To determine if glucose transporters are abnormally expressed in muscle from insulin-resistant subjects, muscle samples were obtained from 10 normal subjects and 6 obese, nondiabetic subjects with severe insulin resistance and acanthosis nigricans. Both GLUT4 total protein and mRNA were normal in the insulin-resistant subjects. Muscle GLUT3 protein and mRNA were lower than controls by 62% and 71%, respectively. GLUT1 mRNA was twice normal, whereas GLUT1 protein content was not significantly increased. GLUT4 protein was markedly redistributed to the muscle plasma membrane in subjects with severe insulin resistance compared with normals (92% v 40% GLUT4 in plasma membrane-enriched fractions, P <.001), whereas the percentage of GLUT1 and GLUT3 protein found in the plasma membrane-enriched fractions was not different from controls. These data document differences in the expression of genes for GLUT1 and GLUT3 in muscle from normal and insulin-resistant subjects. Further, insulin resistance with fasting hyperinsulinemia was associated with a redistribution of GLUT4 to the muscle cell surface with no change in total GLUT4 protein. These data suggest that glucose transporter gene expression and their basal distribution in human muscle are related to insulin resistance and could be determinants of whole body insulin responsiveness.

MR imaging of cerebral extraventricular neurocytoma: a report of 9 cases

Extraventricular neurocytoma is a rare entity, most frequently occurring in brain parenchyma outside the ventricular system. The purpose of this study was to characterize the MR imaging findings in a series of 9 patients with EVN verified by results of pathologic examination. All 9 EVNs were solitary and intracranially located. Eight lesions were well demarcated, and 3 showed intratumoral hemorrhage. The solid parts of 7 tumors were primarily isointense on T1-weighted images and heterogeneously enhanced on T1WI with contrast. Although cerebral EVNs can present a wide spectrum of appearances on MR, the imaging patterns appear to vary according to anatomic location and cellularity. Lesions in frontal or parietal lobes often present as well-demarcated large masses with cystic degeneration, hemorrhage, mild-to-moderate edema, and inhomogeneous enhancement. Moreover, the general isointensity of the solid parts of EVN on T1WI may be of some specificity.

Upregulation of Ras/Raf/ERK1/2 signaling and ERK5 in the brain of autistic subjects

Autism is a neurodevelopmental disorder characterized by impairments in social interaction, verbal communication and repetitive behaviors. A number of studies have shown that the Ras/Raf/ERK1/2 (extracellular signal-regulated kinase) signaling pathway plays important roles in the genesis of neural progenitors, learning and memory. Ras/Raf/ERK1/2 and ERK5 have also been shown to have death-promoting apoptotic roles in neural cells. Recent studies have shown a possible association between neural cell death and autism. In addition, two recent studies reported that a deletion of a locus on chromosome 16, which included the mitogen-activated protein kinase 3 (MAPK3) gene that encodes ERK1, is associated with autism. Most recently, our laboratory detected that Ras/Raf/ERK1/2 signaling activities were significantly enhanced in the brain of BTBR mice that model autism, as they exhibit many autism-like behaviors. We thus hypothesized that Ras/Raf/ERK1/2 signaling and ERK5 could be abnormally regulated in the brain of autistic subjects. In this study, we show that the expression of Ras protein was significantly elevated in the frontal cortex of autistic subjects. C-Raf phosphorylation was increased in the frontal cortex, while both C-Raf and A-Raf activities were enhanced in the cerebellum of autistic subjects. We also detected that both the protein expression and activities of ERK1/2 were significantly upregulated in the frontal cortex of autistic subjects, but not in the cerebellum. Furthermore, we showed that ERK5 protein expression is upregulated in both frontal cortex and cerebellum of autistic subjects. These results suggest that the upregulation of Ras/Raf/ERK1/2 signaling and ERK5 activities mainly found in the frontal cortex of autistic subjects may be critically involved in the pathogenesis of autism.

GLUT3 protein and mRNA in autopsy muscle specimens

GLUT3 is expressed in rat muscle, but this glucose transporter protein has not been identified previously in adult human skeletal muscle. We quantified the rapidity of disappearance of mRNA and protein from human skeletal muscle at room temperature and at 4 degrees C. Fifty percent of the immunologically detectable GLUT3 protein disappeared by 1 hour at 20 degrees C and by 2 hours at 4 degrees C. mRNA for GLUT3 was decreased 50% by 2.2 hours at 20 degrees C and by 24 hours at 4 degrees C. Half of the measurable mRNAs for GLUT4, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), alpha-actin, and beta-myosin disappeared by 0.8 to 2.1 hours at 20 degrees C and by 5.0 to 16.6 hours at 4 degrees C. Previous conclusions that GLUT3 is not expressed in human muscle were likely drawn because of artifacts related to degradation of GLUT3 protein in the specimens prior to study. Because of the rapid degradation of protein and mRNA, autopsy specimens of muscle must be obtained within 6 hours of death, and even then, protein and mRNA data will likely dramatically underestimate their expression in fresh muscle. Some previously published conclusions and recommendations regarding autopsy specimens are not stringent enough to consistently yield useful protein and mRNA.

Selective isolation of human plasma low-density lipoprotein particles containing apolipoproteins B and E by use of a monoclonal antibody to apolipoprotein B

A monoclonal antibody to human plasma apolipoprotein B was used in a single-step immunoaffinity chromatography procedure to isolate a subpopulation of low-density lipoprotein particles from normolipidemic human plasma. The isolated particles were homogeneous in terms of size (20 nm), flotation coefficient (Sf = 9.5), and electrophoretic mobility (beta band). Their protein moiety consisted of apolipoproteins B and E in a molar ratio close to 2. The lipid moiety consisted of 47.3% cholesterol, 4.7% triglycerides, and 48.0% phospholipids. To indicate its characteristic apolipoprotein composition and hydrated density properties, this family of particles was named LP-B:EL2. In most normolipidemic subjects, LP-B:EL2 particles accounted for less than 10% of the total plasma apolipoprotein B content. The LP-B:EL2 particles bound to the membranes of the human hepatoma HepG2 cells in a specific and saturable manner indicative of receptor-mediated binding. Their binding was significantly higher than that of low-density lipoprotein particles containing only apolipoprotein B.

Primary intracranial choriocarcinoma: MR imaging findings

PICCC is the rarest, most malignant primary intracranial GCT. The purpose of this study was to describe and characterize the MR imaging findings in a series of 7 patients (6 males and 1 female; mean age, 11.9 years) with pathologically proved PICCC in our institution from 2004 to 2009. All tumors were located within the pineal (n = 6) or suprasellar (n = 1) regions. On T2-weighted MR imaging, the lesions appeared markedly heterogeneous with areas of both hypointensity and hyperintensity reflecting the histologic heterogeneity, including hemorrhage, fibrosis, cysts, or necrosis. Heterogeneous (n = 7), ringlike (n = 4), and/or intratumoral nodular (n = 3) enhancement was noted on T1-weighted images with gadolinium. These MR imaging findings, combined with patient age and serum β-HCG levels, may prove helpful in distinguishing PICCC from the more common primary brain tumors, thereby avoiding biopsy of this highly vascular tumor.

Suppression of PPN/MG61 attenuates Wnt/beta-catenin signaling pathway and induces apoptosis in human lung cancer

Wingless and int homologue (Wnt) family proteins have been shown to have important roles in the decision of cell fate and behavior at multiple stages during the development and tumorigenesis. One of the Drosophila segment polarity genes, porcupine (porc) gene, encodes an evolutionarily conserved endoplasmic reticulum membrane protein involving in the post-translational processing of the Wnt family proteins. Here, we report that human homologue of Drosophila porc gene, PPN/MG61, was abundantly expressed in human cancer cell lines, but not in normal cells. We also found that PPN/MG61 was overexpressed in primary lung cancer tissue samples, compared to their matched normal tissue samples. Furthermore, when we used small interfering RNA to knock down PPN/MG61 mRNA in lung cancer cells expressing the gene, we observed apoptosis induction, along with decreased activity of Wnt pathway in those lung cancer cells. These data suggest that PPN/MG61 may be a novel marker for human lung cancer and that post-translational modification of the Wnt signal molecules by PPN/MG61 may be important for the function of Wnt pathway in lung cancer.

GLUT-3 expression in human skeletal muscle

Muscle biopsy homogenates contain GLUT-3 mRNA and protein. Before these studies, it was unclear where GLUT-3 was located in muscle tissue. In situ hybridization using a midmolecule probe demonstrated GLUT-3 within all muscle fibers. Fluorescent-tagged antibody reacting with affinity-purified antibody directed at the carboxy-terminus demonstrated GLUT-3 protein in all fibers. Slow-twitch muscle fibers, identified by NADH-tetrazolium reductase staining, possessed more GLUT-3 protein than fast-twitch fibers. Electron microscopy using affinity-purified primary antibody and gold particle-tagged second antibody showed that the majority of GLUT-3 was in association with triads and transverse tubules inside the fiber. Strong GLUT-3 signals were seen in association with the few nerves that traversed muscle sections. Electron microscopic evaluation of human peripheral nerve demonstrated GLUT-3 within the axon, with many of the particles related to mitochondria. GLUT-3 protein was found in myelin but not in Schwann cells. GLUT-1 protein was not present in nerve cells, axons, myelin, or Schwann cells but was seen at the surface of the peripheral nerve in the perineurium. These studies demonstrated that GLUT-3 mRNA and protein are expressed throughout normal human skeletal muscle, but the protein is predominantly found in the triads of slow-twitch muscle fibers.

Glycochenodeoxycholic acid inhibits calcium phosphate precipitation in vitro by preventing the transformation of amorphous calcium phosphate to calcium hydroxyapatite

Calcium hydroxyapatite can be a significant component of black pigment gallstones. Diverse molecules that bind calcium phosphate inhibit hydroxyapatite precipitation. Because glycine-conjugated bile acids, but not their taurine counterparts, bind calcium phosphate, we studied whether glycochenodeoxycholic acid inhibits calcium hydroxyapatite formation. Glycochenodeoxycholic acid (2 mM) totally inhibited transformation of amorphous calcium phosphate microprecipitates to macroscopic crystalline calcium hydroxyapatite. This inhibition was not mediated by decreased Ca2+ activity. Taurocholic acid (2-12 mM) did not affect hydroxyapatite formation, but antagonized glycochenodeoxycholic acid. Both amorphous and crystalline precipitates contained a surface fraction relatively rich in phosphate. The surface phosphate content was diminish by increasing glycochenodeoxycholic acid concentrations, and this relationship was interpreted as competition between bile acid and HPO4(-4) for binding sites on the calcium phosphate surface. A phosphate-rich crystal surface was associated with rapid transition from amorphous to crystalline states. These results indicate that glycochenodeoxycholic acid prevents transformation of amorphous calcium phosphate to crystalline hydroxyapatite by competitively inhibiting the accumulation of phosphate on the crystal embryo surface.

Fingertip replantation at the eponychial level with venous anastomosis: an anatomic study and clinical application

We present an anatomic study of the vein distribution at the eponychial level, in order to standardize outpatient fingertip replantation. The cross sectional anatomy of 100 fingers was studied by dissection following dye injection. The distribution of the veins >0.3 mm was recorded on a pie-chart. Thirty fingers in 27 patients with fingertip amputations at the eponychial level were replanted by anastomosis of the palmar subcutaneous veins, to reconstruct the venous reflux of the amputated digits. The operations were aided by the anatomical study and confirmed that the palmar area is the preferred site for venous anastomosis Following a distal finger amputation at the level of the eponychial fold we propose starting the search for veins between the 3 to 5 o'clock or 7 to 9 o'clock positions, as these are the areas where there are most likely to be suitable veins.

Comparison of GLUT1, GLUT3, and GLUT4 mRNA and the subcellular distribution of their proteins in normal human muscle

Basal, "insulin-independent" glucose uptake into skeletal muscle is provided by glucose transporters positioned at the plasma membrane. The relative amount of the three glucose transporters expressed in muscle has not been previously quantified. Using a combination of qualitative and quantitative ribonuclease protection assay (RPA) methods, we found in normal human muscle that GLUT1, GLUT3, and GLUT4 mRNA were expressed at 90 +/- 10, 46 +/- 4, and 156 +/- 12 copies/ng RNA, respectively. Muscle was fractionated by DNase digestion and differential sedimentation into membrane fractions enriched in plasma membranes (PM) or low-density microsomes (LDM). GLUT1 and GLUT4 proteins were distributed 57% to 67% in LDM, whereas GLUT3 protein was at least 88% in the PM-enriched fractions. These data suggest that basal glucose uptake into resting human muscle could be provided in part by each of these three isoforms.

Characterization of a monoclonal antibody that binds equally to all apolipoprotein and lipoprotein forms of human plasma apolipoprotein B. II. Isolation of apolipoprotein B-containing lipoproteins from human plasma

Monoclonal antibody ('Pan B' antibody) that binds equally to all major forms of human plasma apolipoprotein B was used in an immunoaffinity chromatography procedure to isolate apolipoprotein B-containing lipoproteins from hyperlipidemic human plasma. These lipoproteins were compared with lipoproteins in native plasma, with lipoproteins isolated by polyclonal antibodies and with lipoproteins isolated by the conventional ultracentrifugational method. Judged by the apolipoprotein and lipid composition, lipoproteins isolated with 'Pan B' antibody were virtually identical to those isolated by ultracentrifugation or polyclonal antibodies. Lipoproteins isolated by 'Pan B' antibody were comparable in size and shape to the lipoproteins in native plasma and to the lipoproteins isolated by polyclonal antibodies or ultracentrifugation. The immunoaffinity column with monoclonal 'Pan B' antibody retained all apolipoprotein B-containing lipoproteins and showed significantly higher capacity than polyclonal immunoaffinity column. The column with the highest capacity allowed the isolation from whole plasma of 0.144 mg of apolipoprotein B per ml of gel in less than 2 h.

Identification and characterization of the NTPase activity of classical swine fever virus (CSFV) nonstructural protein 3 (NS3) expressed in bacteria

The nonstructural protein 3 (NS3) of members of the family Flaviviridae possesses multiple enzyme activities that are likely to be essential for viral replication. Here, we cloned and expressed full-length CSFV NS3 protein (NS3FL) and its N-terminal truncated version (ntNS3) in E. coli. NTPase activities of the purified NS3FL and ntNS3 proteins and their reaction conditions were investigated. The results showed that CSFV NS3FL and ntNS3 proteins contained a specific polynucleotide-stimulated NTPase acitivity. Characterization of ntNS3 NTPase activity showed that optimal reaction conditions with respect to pH, MgCl2 and monovalent cations were similar to those of bovine viral diarrhea virus (BVDV) and hepatitis C virus (HCV). Site-directed mutagenesis analysis demonstrated that the GxGK(232)T to GxGAT mutation in the conserved motif I abolished the NTPase activity of ntNS3, whereas substitution of TATPA(354) for TATPV in the motif III had no effect on the enzyme activity. Moreover, the kinetic properties (K(m) and k(cat)) of CSFV NS3 were more similar to those of BVDV. Our results provide insight into the structure-function relationship of CSFV NS3 and facilitate our understanding of its role in the replication cycle of CSFV.

The pro-inflammatory cytokine tumor necrosis factor α stimulates expression of the carnitine transporter OCTN2 (novel organic cation transporter 2) and carnitine uptake via nuclear factor-κB in Madin-Darby bovine kidney cells

Carnitine uptake into tissues is mediated mainly by the novel organic cation transporter 2 (OCTN2), whose expression is upregulated in the liver of early-lactating dairy cows. It has been shown recently that pro-inflammatory cytokines, including tumor necrosis factor α (TNFα), stimulate OCTN2 expression and carnitine uptake in intestinal cells and inflamed intestinal mucosa. Given that many early-lactating dairy cows show typical signs of hepatic and systemic inflammation, such as elevated concentrations of circulating TNFα and activation of the key regulator of inflammation, nuclear factor κB (NF-κB), in tissues, it is possible that upregulation of OCTN2 and increase of carnitine uptake by TNFα is mediated by NF-κB, a mechanism that might contribute to the upregulation of OCNT2 in the liver of early-lactating dairy cows. Thus, in the present study, we tested the hypothesis that TNFα stimulates OCTN2 gene expression and carnitine uptake via NF-κB in the bovine Madin-Darby bovine kidney (MDBK) cell line. Treatment with TNFα caused activation of NF-κB, increased the mRNA and protein concentration of OCTN2, and stimulated the uptake of carnitine in MDBK cells. In contrast, combined treatment of MDBK cells with TNFα and the NF-κB inhibitor BAY 11-7085 completely blocked the effect of TNFα on OCTN2 mRNA and protein concentration and uptake of carnitine. These findings suggest that the bovine OCTN2 gene and carnitine uptake are regulated by NF-κB. Future studies are required to show the in vivo relevance of this regulatory mechanism in cattle.

Molecular cloning and chromosomal assignment of the porcine 54 and 56 kDa vacuolar H(+)-ATPase subunit gene (V-ATPase)

Vacuolar proton-translocating ATPases (V-ATPase) are multisubunit enzyme complexes located in the membranes of eukaryotic cells regulating cytoplasmic pH. So far, nothing is known about the genomic organization and chromosomal location of the various subunit genes in higher eukaryotes. Here we describe the isolation and analysis of a cDNA coding for the 54- and 56-kDa porcine V-ATPase subunit alpha and beta isoforms. We have determined the genomic structure of the V-ATPase subunit gene spanning at least 62 kb on Chromosome (Chr) 4q14-q16. It consists of 14 exons with sizes ranging from 54 bp to 346 bp, with a non-coding first exon and an alternatively spliced seventh exon leading to two isoforms. The 5' end of the V-ATPase cDNA was isolated by RACE-PCR. The V-ATPase alpha isoform mRNA, lacking the seventh exon, has an open reading frame of 1395 nucleotides encoding a hydrophilic protein of 465 amino acids with a calculated molecular mass of 54.2 kDa and a pI of 7.8, whereas the beta isoform has a length of 1449 nucleotides encoding a protein of 483 amino acids with a calculated molecular mass of 55.8 kDa. Amino acid and DNA sequence comparison revealed that the porcine V-ATPase subunit exhibits a significant homology to the VMA13 subunit of Saccharomyces cerevisiae V-ATPase complex and V-ATPase subunit of Caenorhabditis elegans.

Effects of tetra-arsenic tetra-sulfide on BXSB lupus-prone mice: a pilot study

Systemic lupus erythematosus (SLE) is an autoimmune disease of uncertain etiology that affects multiple tissues and organs. Arsenic trioxide (ATO) has been used in lupus-prone mice with a regulatory effect on immune abnormality. Tetra-arsenic tetra-sulfide (As4S4), a traditional Chinese medicine, is effective on acute promyelocytic leukemia with mild side effects than ATO. In this study, a pilot study was performed to investigate the effects and the mechanism of As4S4 on the lupus-prone BXSB mice. Improvement of monocytosis (p<0.05) in spleen and decreased serum interleukin-6 (IL-6) (p=0.0277) were observed with As4S4 treatment. As4S4-treated mice exhibited amelioration of skin, liver and renal disease with mild side effects. Histological analysis revealed that As4S4 suppressed immune complex deposition, mesangial proliferation and inflammatory cell infiltration in kidney and liver. Our study support that As4S4 selectively suppresses cutaneous lupus and nephritis in BXSB mice and might be a potential treatment for SLE.