Necrotizing enterocolitis after intravitreal bevacizumab in an infant with Incontinentia Pigmenti - a case report.

BACKGROUND: Incontinentia Pigmenti is a rare disease affecting multiple organs. Fifty of patients show affection of the eye with retinopathy and possible amaurosis being the worst outcome. Treatment has commonly been panretinal laser coagulation but intravitreal application of bevacizumab as VEGF-inhibitor has shown to effectively suppress retinal neovascularization. CASE PRESENTATION: A six-week-old female infant with Incontinentia Pigmenti developed a foudroyant necrotizing enterocolitis shortly after intravitreal injection of bevazicumab due to a retinopathy with impending tractional detachment of the left eye. Since the onset of abdominal symptoms occurred immediately after the intravitreal application, a link between the two events seemed likely. Sequential analyses of the VEGF serum concentrations showed a massive suppression of endogenous VEGF with only a very slow recovery over weeks. Such a severe systemic adverse event has not been reported after intravitreal treatment with bevacizumab in an infant. CONCLUSION: This case report shows a relevant systemic uptake of bevacizumab after intravitreal application as suppressed VEGF levels show. There seems to be a connection between suppressed VEGF levels and the onset of necrotizing enterocolitis. Therefore, treatment with bevacizumab should be carefully considered and further research is needed to assess this drug's safety profile.

Physical activity and the risk of Barrett's esophagus.

Physical activity either directly or through influencing body fat may affect the risk of Barrett's esophagus (BE). However, the effect of physical activity on the risk of developing BE has not been examined. We conducted a case-control study among consecutive eligible patients either scheduled for elective endoscopy or recruited from primary care clinics to undergo a study endoscopy. Study participants completed the International Physical Activity Questionnaire (IPAQ) short form that measures physical activity during the past 7 days. We categorized level of physical activity by low, moderate, or high and estimated metabolic equivalent minutes per week (MET min/week). We calculated odds ratios (ORs) using logistic regression models and adjusted for age, sex, race, gastroesophageal reflux disease symptoms, Helicobacter pylori infection, body mass index, and waist-to-hip ratio. There were 307 cases with BE and 1724 controls (1262 from endoscopy and 462 from the primary care clinic) with IPAQ information. BE cases were more likely to be in the high-category physical activity category than controls (14.3% vs. 11.5% P = 0.08). However, there were no differences in the overall average MET min/week for walking between BE cases and controls (909 vs. 561; P = 0.16), with similar findings among those with moderate activity (1094 vs. 755, P = 0.18) or vigorous activity (784 vs. 826, P = 0.93). In multivariable logistic regression, physical activity level was not significantly associated with BE (OR = 1.19, 95% confidence interval: 0.82-1.73). Recent amount and intensity of physical activity are not associated with a reduction in the risk of BE. Studies are required to examine the long-term effects of physical activity.

Downregulation of interleukin-18-mediated cell signaling and interferon gamma expression by the hepatitis B virus e antigen.

UNLABELLED: The mechanisms by which hepatitis B virus (HBV) establishes and maintains chronic hepatitis B infection (CHB) are poorly defined. Innate immune responses play an important role in reducing HBV replication and pathogenesis. HBV has developed numerous mechanisms to escape these responses, including the production of the secreted hepatitis B e antigen (HBeAg), which has been shown to regulate antiviral toll-like receptor (TLR) and interleukin-1 (IL-1) signaling. IL-18 is a related cytokine that inhibits HBV replication in hepatoma cell lines and in the liver through the induction of gamma interferon (IFN-γ) by NK cells and T cells. We hypothesized that HBV or HBV proteins inhibit IFN-γ expression by NK cells as an accessory immunomodulatory function. We show that HBeAg protein inhibits the NF-κB pathway and thereby downregulates NK cell IFN-γ expression. Additionally, IFN-γ expression was significantly inhibited by exposure to serum from individuals with HBeAg-positive but not HBeAg-negative chronic HBV infection. Further, we show that the HBeAg protein suppresses IL-18-mediated NF-κB signaling in NK and hepatoma cells via modulation of the NF-κB pathway. Together, these findings show that the HBeAg inhibits IL-18 signaling and IFN-γ expression, which may play an important role in the establishment and/or maintenance of persistent HBV infection. IMPORTANCE: It is becoming increasingly apparent that NK cells play a role in the establishment and/or maintenance of chronic hepatitis B infection. The secreted HBeAg is an important regulator of innate and adaptive immune responses. We now show that the HBeAg downregulates NK cell-mediated IFN-γ production and IL-18 signaling, which may contribute to the establishment of infection and/or viral persistence. Our findings build on previous studies showing that the HBeAg also suppresses the TLR and IL-1 signaling pathways, suggesting that this viral protein is a key regulator of antiviral innate immune responses.

α1 -Adrenergic receptor-induced cytoskeletal organization and cell motility in CCL39 fibroblasts requires phospholipase D1.

The role of phospholipase D (PLD) in cytoskeletal reorganization, ERK activation, and migration is well established. Both isoforms of PLD (PLD1 and PLD2) can independently activate stress fiber formation and increase ERK phosphorylation. However, the isoform's specificity, upstream activators, and downstream targets of PLD that coordinate this process are less well understood. This study explores the role of α(1) -adrenergic receptor stimulation and its effect on PLD activity. We demonstrate that PLD1 activators, RhoA, and PKCα are critical for stress fiber formation and ERK activation, and enhance the production of phosphatidic acid (PA) upon phenylephrine addition. Ectopic expression of dominant negative PLD1 and not PLD2 blocks ERK activation, inhibits stress fiber formation, and reduces cell motility in CCL39 fibroblasts. Furthermore, we demonstrate the mechanism for PLD1 activation of ERK involves Ras. This work indicates that PLD1 plays a novel role mediating growth factor and cell motility events in α(1) -adrenergic receptor-activated cells.

Urokinase plasminogen activator receptor induced non-small cell lung cancer invasion and metastasis requires NHE1 transporter expression and transport activity.

BACKGROUND: Non-small cell lung cancers (NSLC) are aggressive cancers that are insensitive to chemotherapies and accounts for nearly 33% of all cancer deaths in the United States. Two hallmarks of cancer that allow cells to invade and metastasize are sustained proliferation and enhanced motility. In this study we investigate the relationship between urokinase plasminogen activator (uPA)/uPA receptor (uPAR) signaling and Na(+)/H(+) exchanger isoform 1 (NHE1) expression and activity. METHODS AND RESULTS: The addition of 10nM uPA increased the carcinogenic potential of three NSCLC cell lines, NCI-H358, NCI-H460, and NCI-H1299. This included an increase in the rate of cell proliferation 1.6 to 1.9 fold; an increase in the percentage of cells displaying stress fibers 3.05 to 3.17 fold; and an increase in anchorage-independent growth from 1.64 to 2.0 fold. In each of these cases the increase was blocked when the experiments were performed with NHE1 inhibited by 10 µM EIPA (ethylisopropyl amiloride). To further evaluate the role of uPA/uPAR and NHE1 in tumor progression we assessed signaling events using full-length uPA compared to the uPA amino terminal fragment (ATF). Comparing uPA and ATF signaling in H460 cells, we found that both uPA and ATF increased stress fiber formation approximately 2 fold, while uPA increased matrix metalloproteinase 9 (MMP9) activity 5.44 fold compared to 2.81 fold for ATF. To expand this signaling study, two new cell lines were generated, one with reduced NHE1 expression (H460 NHE1 K/D) and one with reduced uPAR expression (H460 uPAR K/D). Using the K/D cell lines we found that neither uPA nor ATF could stimulate stress fiber formation or MMP9 activity in cells with dramatically decreased NHE1 or uPAR expression. Finally, using in vivo tumor formation studies in athymic mice we found that when mice were injected with H460 cells 80% of mice formed tumors with an average volume of 390 mm(3). This was compared to 20% of H460 uPAR K/D injected mice forming tumors with an average volume of 15 mm(3) and 10% of H460 NHE1 K/D injected mice forming tumors with an average volume of 5 mm(3). CONCLUSION: Taken together, these data demonstrate that uPA/uPAR-mediated tumor progression and metastasis requires NHE1 in NSCLC cells and suggests a potential therapeutic approach to blocking cancer progression.

Cloning of Tabby, the murine homolog of the human EDA gene: evidence for a membrane-associated protein with a short collagenous domain.

X-Linked hypohidrotic ectodermal dysplasia (XLHED) is a human congenital disorder resulting in abnormal tooth, hair and sweat gland development. A candidate gene for the disorder has been cloned, but the function and full size of its putative protein product is unclear. We have identified a candidate cDNA for the mouse Tabby gene (Ta), which, based on phenotype and syntenic mapping, is postulated to represent the analogous murine disorder. Mutations have been identified in three different Ta alleles and Northern analysis indicates that the gene is expressed at increasing levels during embryogenesis (11-17 days p.c.), the period when affected structures develop. The putative protein product encoded by exon 1 is highly homologous (87% identical) to the predicted EDA protein product (135 amino acids), including the presence of a single transmembrane domain. However, the murine cDNA also encodes an additional 246 amino acids, which contains a short collagenous domain (Gly-X-Y)19. This predicted structure is similar to a number of membrane-associated proteins with either single or multiple collagenous domains in their extracellular C-terminal regions. Since mutations can only be identified in 10-15% of families with XLHED, it is likely that additional homologous exons exist for the human EDA gene. Hybridization of YACs from the EDA region with the Ta cDNA support this hypothesis. The predicted extracellular collagenous domain of this membrane protein may play a key role in epithelial-mesenchymal interactions, defects of which are thought to underlie the Ta/XLHED phenotype.

Cloning, mapping and expression analysis of barley MADS-box genes.

Six MADS-box cDNA clones were isolated by heterologous screening from a barley inflorescence cDNA library. Based on sequence comparison to known MADS-box genes, the barley MADS-box (BM) genes were grouped into three distinct phylogenetic subclasses of the MADS-box gene family. The three MADS-box genes BM3, BM5 and BM8 share similarities with genes of the SQUAMOSA (SQUA) subgroup, while BM7 and BM9 belong to the AGAMOUS-LIKE 2 (AGL2) subgroup. BM1 resembles MADS-box genes described as solitary sequences or orphan genes. Expression analysis of the barley MADS-box genes revealed expression patterns that are not characteristic of the barley MADS-box genes of the SQUA subgroup. while expression of BM7 and BM9 was largely as expected for the AGL2 subgroup. BM1 is mainly expressed in vegetative tissues and its primary transcript undergoes alternative splicing such that the corresponding mRNAs differ by two codons. The genes BM1, BM3 and BM8 were mapped by analysis of single-nucleotide polymorphisms onto barley chromosomes 4, 2 and 7, respectively.