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BACKGROUND: The number of primary anterior cruciate ligament reconstructions is increasing rapidly; the number of failing grafts and need for revision surgery have also risen. HYPOTHESIS: Revision anterior cruciate ligament reconstruction will produce similar results to those of primary reconstruction, and there may be different results according to graft materials. STUDY DESIGN: Case control study; Level of evidence, 3. METHODS: Fifty-nine revision surgeries were performed at 1 institution between January 1997 and October 2005. Fifty-five patients (56 operations) were followed. The results of 117 patients (117 knees) treated with arthroscopic primary anterior cruciate ligament reconstruction using double-looped semitendinosus and gracilis autograft from September 2001 to November 2002 were also evaluated. Clinical and stability results between primary and revision anterior cruciate reconstruction were compared. For the revision surgery, 21 (37.5%) knees had revision reconstruction with previously unharvested ipsilateral double-looped semitendinosus and gracilis autograft. Twenty (35.7%) were bone-patellar tendon-bone allograft, and 15 (26.8%) were Achilles allograft. The details of the technique varied according to the original graft choice and the abnormality encountered. Concomitant procedures were necessary in 32 (57.1%) of 56 knees. Clinical and stability results according to the different graft materials were also compared. RESULTS: There were significant improvements in the scores for subjective, objective forms (P < .001), and stability (P < .001). However, the clinical results of revision surgery were inferior to primary reconstruction (P < .001), but as regards stability, the difference between primary and revision cases was not significant (P = .338). There was no difference in clinical and stability results in different groups of graft material (P = .160-.690). CONCLUSION: Revision anterior cruciate ligament reconstruction could improve clinical and stability results, but the clinical results were inferior to those of primary reconstruction. This study also demonstrated that the success of the operation did not depend on the choice of graft materials. [ABSTRACT FROM AUTHOR]

The skin seems to rejuvenate upon exposure to factors within the circulation of young organisms. Intrinsic factors that modulate skin aging are poorly understood. We used heterochronic parabiosis and aptamer-based proteomics to identify serum-derived rejuvenating factors. We discovered a novel extracellular function of hyaluronan and proteoglycan link protein 1 (HAPLN1). Its serum levels decreased with age, disturbing the integrity of the skin extracellular matrix, which is predominantly composed of collagen I and hyaluronan; levels of various markers, which decrease in aged skin, were significantly restored in vivo and in vitro by the administration of recombinant human HAPLN1 (rhHAPLN1). rhHAPLN1 protected transforming growth factor beta receptor 2 on the cell surface from endocytic degradation via mechanisms such as regulation of viscoelasticity, CD44 clustering. Moreover, rhHAPLN1 regulated the levels of nuclear factor erythroid 2-related factor 2, phosphorylated nuclear factor kappa B, and some cyclin-dependent kinase inhibitors such as p16 and p21. Therefore, rhHAPLN1 may act as a novel biomechanical signaling protein to rejuvenate aged skin., Competing Interests: Declaration of competing interest Z.F, GW.Y, D.K, JM.J, and IC.S are employees and DK.K is Chairman & Chief Science Officer of HaplnScience Inc. JM.J and DK.K are stockholders of HaplnScience Inc.. Z.F, MJ.B, and DK.K are inventors of the patent (Publication number: 20,200,000,700. Composition for skin aging measurement, prevention or alleviation, using HAPLN1) submitted by Chung-Ang University that covers a biomarker composition for measuring skin aging using HAPLN1 and a pharmaceutical composition for preventing or alleviating skin aging, cosmetic composition, or health functional foods. All other authors declare that they have no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Cardiovascular diseases (CVDs) are the most common cardiovascular system disorders. Cellular senescence is a key mechanism associated with dysfunction of aged vascular endothelium. Hyaluronic acid and proteoglycan link protein 1 (HAPLN1) has been known to non-covalently link hyaluronic acid (HA) and proteoglycans (PGs), and forms and stabilizes HAPLN1-containing aggregates as a major component of extracellular matrix. Our previous study showed that serum levels of HAPLN1 decrease with aging. Here, we found that the HAPLN1 gene expression was reduced in senescent human umbilical vein endothelial cells (HUVECs). Moreover, a recombinant human HAPLN1 (rhHAPLN1) decreased the activity of senescence-associated β-gal and inhibited the production of senescence-associated secretory phenotypes, including IL-1β, CCL2, and IL-6. rhHAPLN1 also down-regulated IL-17A levels, which is known to play a key role in vascular endothelial senescence. In addition, rhHAPLN1 protected senescent HUVECs from oxidative stress by reducing cellular reactive oxygen species levels, thus promoting the function and survival of HUVECs and leading to cellular proliferation, migration, and angiogenesis. We also found that rhHAPLN1 not only increases the sirtuin 1 (SIRT1) levels, but also reduces the cellular senescence markers levels, such as p53, p21, and p16. Taken together, our data indicate that rhHAPLN1 delays or inhibits the endothelial senescence induced by various aging factors, such as replicative, IL-17A, and oxidative stress-induced senescence, thus suggesting that rhHAPLN1 may be a promising therapeutic for CVD and atherosclerosis.

Hair loss is a common condition that can have a negative impact on an individual's quality of life. The severe side effects and the low efficacy of current hair loss medications create unmet needs in the field of hair loss treatment. Hyaluronan and Proteoglycan Link Protein 1 (HAPLN1), one of the components of the extracellular matrix, has been shown to play a role in maintaining its integrity. HAPLN1 was examined for its ability to impact hair growth with less side effects than existing hair loss treatments. HAPLN1 was predominantly expressed in the anagen phase in three stages of the hair growth cycle in mice and promotes the proliferation of human hair matrix cells. Also, recombinant human HAPLN1 (rhHAPLN1) was shown to selectively increase the levels of transforming growth factor-β receptor II in human hair matrix cells. Furthermore, we observed concomitant activation of the ERK1/2 signaling pathway following treatment with rhHAPLN1. Our results indicate that rhHAPLN1 elicits its cell proliferation effect via the TGF-β2-induced ERK1/2 pathway. The prompt entering of the hair follicles into the anagen phase was observed in the rhHAPLN1-treated group, compared to the vehicle-treated group. Insights into the mechanism underlying such hair growth effects of HAPLN1 will provide a novel potential strategy for treating hair loss with much lower side effects than the current treatments.

Rheumatoid arthritis (RA) is a multifactorial immune-mediated disease, the pathogenesis of which involves different cell types. T-cell activation plays an important role in RA. Therefore, inhibiting T-cell activation is one of the current therapeutic strategies. Cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig), also known as abatacept, reduces cytokine secretion by inhibiting T-cell activation. To achieve a homeostatic therapeutic effect, CTLA4-Ig has to be administered repeatedly over several weeks, which limits its applicability in RA treatment. To overcome this limitation, we increased the number of sialic acid-capped antennas by genetically engineering the CTLA4 region to increase the therapeutic effect of CTLA4-Ig. N-acetylglucosaminyltransferase (GnT) and α2,6-sialyltransferase (α2,6-ST) were co-overexpressed in Chinese hamster ovary (CHO) cells to generate a highly sialylated CTLA4-Ig fusion protein, named ST6. The therapeutic and immunogenic effects of ST6 and CTLA4-Ig were compared. ST6 dose-dependently decreased paw edema in a mouse model of collagen-induced arthritis and reduced cytokine levels in a co-culture cell assay in a similar manner to CTLA4-Ig. ST6- and CTLA4-Ig-induced T cell-derived cytokines were examined in CD4 T cells isolated from peripheral blood mononuclear cells after cell killing through irradiation followed by flow- and magnetic-bead-assisted separation. Interestingly, compared to CTLA4-Ig, ST6 was substantially less immunogenic and more stable and durable. Our data suggest that ST6 can serve as a novel, less immunogenic therapeutic strategy for patients with RA.

Intestinal epithelial cells are adapted in mucosal hypoxia and hypoxia-inducible factors in these cells can fortify barrier integrity to support mucosal tissue healing. Here we investigated whether hypoxia-related pathways could be proposed as potential therapeutic targets for inflammatory bowel disease. We developed a novel hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor, CG-598 which stabilized HIF-1α in the gut tissue. Treatment of CG-598 did not affect extra-intestinal organs or cause any significant adverse effects such as erythropoiesis. In the experimental murine colitis model, CG-598 ameliorated intestinal inflammation with reduction of inflammatory lesions and pro-inflammatory cytokines. CG-598 treatment fortified barrier function by increasing the expression of intestinal trefoil factor, CD73, E-cadherin and mucin. Also, IL-10 and IL-22 were induced from lamina propria CD4 + T-cells. The effectiveness of CG-598 was comparable to other immunosuppressive therapeutics such as TNF-blockers or JAK inhibitors. These results suggest that CG-598 could be a promising therapeutic candidate to treat inflammatory bowel disease., Competing Interests: Y-DK, AL, JC, HH, JMC, and YH were employed by the company CrystalGenomics, Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Kim, Yi, Kim, Lee, Chung, Ha, Cho, Kim, Ko, Cheon, Hong and Chang.)

Histone deacetylase inhibitors (HDACis) are well-known epigenetic regulators with therapeutic potential in various diseases. Recent studies have shown that HDACis are involved in immune-mediated anti-cancer effects and may modulate the activity of immunotherapy agents. CG-745, a histone deacetylase inhibitor, has shown anti-cancer effects in pancreatic cancer, colorectal cancer, and non-small cell lung cancer. However, the exact role of CG-745 within the immune system is largely unknown. In this study, we have shown that CG-745 induces microenvironment changes promoting anti-cancer effect of anti-PD-1 antibody in syngeneic mouse models. Specifically, CG-745 induces or extends IL-2 and IFN-γ expression with or without additional stimulation, and increases proliferation of cytotoxic T cells and NK cells, while inhibiting proliferation of regulatory T cells. The analysis of immune cell distribution in the tumor microenvironment and spleen reveals that CG-745 suppresses M2 macrophage polarization and decreases the myeloid-derived suppressor cells. Recent advances in immunotherapy highlight the anti-cancer effects of immune checkpoint inhibitor despite a relatively limited clinical benefit in the subset of patients. Our results indicate that CG-745 enables the synergistic effects of the immune checkpoint inhibitor combination therapy in various cancers by suppressing tumor microenvironment., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Neurotransmitter release is mediated by ceramide, which is generated by sphingomyelin hydrolysis. In the present study, we examined whether synaptosomal-associated protein 25 (SNAP-25) is involved in ceramide production and exocytosis. Neutral sphingomyelinase 2 (nSMase2) was partially purified from bovine brain and we found that SNAP-25 was enriched in the nSMase2-containing fractions. In rat synaptosomes and PC12 cells, the immunoprecipitation pellet of anti-SNAP-25 antibody showed higher nSMase activity than the immunoprecipitation pellet of anti-nSMase2 antibody. In PC12 cells, SNAP-25 was colocalized with nSMase2. Transfection of SNAP-25 small interfering RNA (siRNA) significantly inhibited nSMase2 translocation to the plasma membrane. A23187-induced ceramide production was concomitantly reduced in SNAP-25 siRNA-transfected PC12 cells compared with that in scrambled siRNA-transfected cells. Moreover, transfection of SNAP-25 siRNA inhibited dopamine release, whereas addition of C 6 -ceramide to the siRNA-treated cells moderately reversed this inhibition. Additionally, nSMase2 inhibition reduced dopamine release. Collectively, our results indicate that SNAP-25 interacts with nSMase2 during ceramide production, which mediates exocytosis and neurotransmitter release., (Copyright © 2019. Published by Elsevier Ltd.)

Background/aim: Interleukin (IL)-1β is a pro-inflammatory cytokine that has recently been established as a stimulator of angiogenesis via regulation of proangiogenic factor expression in the tumor microenvironment. This study aimed to demonstrate the inhibitory effects of Robinia pseudoacacia leaf extract (RP) on IL-1β-mediated tumor angiogenesis., Materials and Methods: Secreted embryonic alkaline phosphatase (SEAP) reporter gene assay, ex vivo and in vitro tube formation assay, western blot, and quantitative PCR were used to analyze the inhibitory effect of RP on IL-1β-mediated angiogenesis., Results: RP inhibited secretion of SEAP, blocked IL-1β signaling, and inhibited IL-1β-mediated angiogenesis in ex vivo and in vitro assays. RP inhibited nuclear translocation of NF-ĸB by suppressing phosphorylation of IL-1β signaling protein kinases and inhibited mRNA expression of IL-1β-induced pro-angiogenic factors including VEGFA, FGF2, ICAM1, CXCL8, and IL6., Conclusion: RP suppressed IL-1β-mediated angiogenesis and, thus, could be a promising agent in anticancer therapy., (Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Ceramide metabolism is known to be an essential etiology for various diseases, such as atopic dermatitis and Gaucher disease. Glucosylceramide synthase (GCS) is a key enzyme for the synthesis of glucosylceramide (GlcCer), which is a main ceramide metabolism pathway in mammalian cells. In this article, we developed a liquid chromatography-tandem mass spectrometry (LCMS/MS) method to determine GCS activity using synthetic non-natural sphingolipid C8-ceramide as a substrate. The reaction products, C8-GlcCer for GCS, could be separated on a C18 column by reverse-phase high-performance liquid chromatography (HPLC). Quantification was conducted using the multiple reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z 588.6 → 264.4 for C8-GlcCer at positive ionization mode. The calibration curve was established over the range of 0.625-160 ng/mL, and the correlation coefficient was larger than 0.999. This method was successfully applied to detect GCS in the human hepatocellular carcinoma cell line (HepG2 cells) and mouse peripheral blood mononuclear cells. We also evaluated the inhibition degree of a known GCS inhibitor 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) on GCS enzymatic activity and proved that this method could be successfully applied to GCS inhibitor screening of preventive and therapeutic drugs for ceramide metabolism diseases, such as atopic dermatitis and Gaucher disease.

Drug repositioning is a strategy that explores new pharmaceutical applications of previously launched or failed drugs, and is advantageous since it saves capital and time. In this study, we examined the inhibition of TLR2 signaling by drug candidates. HEK-Blue™-hTLR2 cells were pretreated with drugs and stimulated using the TLR2 ligand, Pam3CSK4. Among the drugs that inhibited TLR2 signaling, we selected TRIAC, which is yet to be patented. Pretreatment with TRIAC decreased the TLR2 level and the phosphorylation of Akt and MAPKs in HEK-Blue™-hTLR2 cells. Since TLR2 is overexpressed in patients with acute hepatitis, we confirmed that TRIAC alleviates necrosis in a mouse model of Con A-induced acute hepatitis. The serum AST and ALT levels are indicators of liver damage, and are increased in Con A-induced hepatitis. Additionally, TLR2 and inflammatory cytokine levels are increased following administration of Con A and lead to liver damage. TRIAC decreased the serum levels of AST and ALT, and reduced liver tissue necrosis in mice with Con A-induced acute fulminant liver damage, by reducing the levels of inflammatory cytokines. In conclusion, TRIAC alleviates inflammation in mouse models of Con A-induced hepatitis by inhibiting the phosphorylation of Akt and MAPKs, the sub-mechanisms underlying TLR2 signaling.

Autophagy is essential for optimal cell function and survival, and the entire process accompanies membrane dynamics. Ceramides are produced by different enzymes at different cellular membrane sites and mediate differential signaling. However, it remains unclear which ceramide-producing pathways/enzymes participate in autophagy regulation under physiological conditions such as nutrient starvation, and what the underlying mechanisms are. In this study, we demonstrate that among ceramide-producing enzymes, neutral sphingomyelinase 2 (nSMase2) plays a key role in autophagy during nutrient starvation. nSMase2 was rapidly and stably activated upon starvation, and the enzymatic reaction in the Golgi apparatus facilitated autophagy through the activation of p38 MAPK and inhibition of mTOR. Moreover, nSMase2 played a protective role against cellular damage depending on autophagy. These findings suggest that nSMase2 is a novel regulator of autophagy and provide evidence that Golgi-localized ceramides participate in cytoprotective autophagy against starvation.

Dopamine (DA) reuptake is the primary mechanism to terminate dopaminergic transmission in the synaptic cleft. The dopamine transporter (DAT) has an important role in the regulation of DA reuptake. This study provides anatomical and physiological evidence that DAT recycling is regulated by ceramide kinase via the sphingomyelin pathway. First, the results show that DAT and neutral sphingomyelinase 2 (nSMase2) were successfully co-precipitated from striatal samples and were colocalized in the mouse striatum or PC12 cells. We also identified a protein-protein interaction between nSMase2 and DAT through in situ proximity ligation assay experiments in the mouse striatum. Second, dopamine (DA) stimulated the formation of ceramide and increased nSMase activity in PC12 cells, while treatment with a cell-permeable ceramide-1-phosphate (C1P) increased DA uptake. Third, we used inhibitors and siRNA to inhibit nSMase2 and ceramide kinase and observed the effects on DAT recycling in PC12 cells. Treatment with ceramide kinase inhibitor K1, or nSMase inhibitor GW4869, decreased DA uptake in PC12 cells, although the application of FB 1 , a ceramide synthase inhibitor, did not affect DA uptake. Transfection of nSMase2 and CERK siRNA decreased DAT surface level in PC12 cells. These results suggested that SM-derived C1P affects cell surface levels of DAT., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Acute lung injury (ALI) is a respiratory failure disease and the major source of mortality in the critically ill patients. The main pathological changes involved in ALI include the excessive recruitment and activation of neutrophils by increased pro-inflammatory mediators. However, any specific therapy for ALI has not been developed. The objective of this study was to investigate protective effects of parthenolide, a sesquiterpene lactone produced in feverfew, on LPS-induced lung injury. In the present study, parthenolide treatment reduced infiltration of inflammatory cells, airway permeability and production of pro-inflammatory cytokines in LPS-induced ALI mouse model. Further, LPS-stimulated phosphorylation of NF-κB, the key regulatory transcription factor in ALI, was inhibited by parthenolide treatment in lung epithelial BEAS-2B cells and alveolar macrophage MH-S cells. These results suggest that parthenolide may provide a beneficial therapeutic strategy for ALI.

Paraquat dichloride (N,N-dimethyl-4-4'-bipiridinium, PQ) is an extremely toxic chemical that is widely used in herbicides. PQ generates reactive oxygen species (ROS) and causes multiple organ failure. In particular, PQ has been reported to be an immunotoxic agrochemical compound. PQ was shown to decrease the number of macrophages in rats and suppress monocyte phagocytic activity in mice. However, the effect of PQ on macrophage cell viability remains unclear. In this study, we evaluated the cytotoxic effect of PQ on the mouse macrophage cell line, RAW264.7 and its possible mechanism of action. RAW264.7 cells were treated with PQ (0, 75, and 150 μM), and cellular apoptosis, mitochondrial membrane potential (MMP), and intracellular ROS levels were determined. Morphological changes to the cell nucleus and cellular apoptosis were also evaluated by DAPI and Annexin V staining, respectively. In this study, PQ induced apoptotic cell death by dose-dependently decreasing MMP. Additionally, PQ increased the cleaved form of caspase-3, an apoptotic marker. In conclusion, PQ induces apoptosis in RAW264.7 cells through a ROS-mediated mitochondrial pathway. Thus, our study improves our knowledge of PQ-induced toxicity, and may give us a greater understanding of how PQ affects the immune system.

In the present study, we examined the mechanisms underlying the effect of DA-9801 on neurite outgrowth. We found that DA-9801 elicits its effects via the mitogen-activated protein kinase (MEK) extracellular signal-regulated kinase (ERK)1/2-cAMP response element-binding protein (CREB) pathway. DA-9801, an extract from a mixture of Dioscorea japonica and Dioscorea nipponica, was reported to promote neurite outgrowth in PC12 cells. The effects of DA-9801 on cell viability and expression of neuronal markers were evaluated in PC12 cells. To investigate DA-9801 action, specific inhibitors targeting the ERK signaling cascade were used. No cytotoxicity was observed in PC12 cells at DA-9801 concentrations of less than 30 µg/mL. In the presence of nerve growth factor (NGF, 2 ng/mL), DA-9801 promoted neurite outgrowth and increased the relative mRNA levels of neurofilament-L (NF-L), a marker of neuronal differentiation. The Raf-1 inhibitor GW5074 and MEK inhibitor PD98059 significantly attenuated DA-9801-induced neurite outgrowth. Additionally, the MEK1 and MEK2 inhibitor SL327 significantly attenuated the increase in the percentage of neurite-bearing PC12 cells induced by DA-9801 treatment. Conversely, the selective p38 mitogen-activated protein kinase inhibitor SB203580 did not attenuate the DA-9801 treatment-induced increase in the percentage of neurite-bearing PC12 cells. DA-9801 enhanced the phosphorylation of ERK1/2 and CREB in PC12 cells incubated with and without NGF. Pretreatment with PD98059 blocked the DA-9801-induced phosphorylation of ERK1/2 and CREB. In conclusion, DA-9801 induces neurite outgrowth by affecting the ERK1/2-CREB signaling pathway. Insights into the mechanism underlying this effect of DA-9801 may suggest novel potential strategies for the treatment of peripheral neuropathy.

Paraquat (PQ), one of the most widely used herbicides, has been used for several decades in agriculture. Some studies suggest that PQ has effects on the immune system. Moreover, previous studies have shown that PQ imparted some immunosuppressive effects. In the present study, cytotoxicity assays using splenic NK cells from mice treated for 28 days with PQ (at 0.2, 1, and 5 mg/kg) were performed to determine whether PQ altered the function of NK cells. Given that PQ was expected to induce an immunosuppressive effect, it was hypothesized that a gene involved in cellular metal ion homeostasis, metallothionein-1 (MT-1), could play an important role in this outcome. This belief was based on the fact that MT1 encodes a protein responsible for zinc ion homeostasis, and that a reduction in free zinc ion levels impairs NK cell function. The results showed that PQ treatments led to increased MT expression in several organs (liver, kidneys, testes) and in splenocytes, caused a reduction of both free zinc ions in sera and in free intracellular zinc, and reduced the expression of GATA-3, a zinc-finger transcription factor important for maturation and activity of T-cells and NK cells. These results provide a basis for a new molecular mechanism to describe potential immunosuppressive effects of PQ in vivo.

Background: Poly(ADP-ribose) polymerase 1 (PARP1) is a chromatin-associated enzyme that participates in processes such as transcription and DNA repair through the regulation of chromatin structure. Accumulating evidence suggests an important role for PARP1 enzymatic activity in promoting CNS inflammation by facilitating the expression of inflammatory cytokines in glial cells. However, the molecular mechanisms by which PARP1 enzymatic activity mediates this process are not well understood. In this report we sought to determine the molecular mechanisms by which PARP1 enzymatic activity facilitates the expression of Il1β and TNF in LPS-stimulated BV2 cells., Methods: PARP1 enzymatic activity and histone ADP-ribosylation were measured in LPS-stimulated BV2 cells by radioactive labelling with (32)P-NAD(+). To assess the effect of histone ADP-ribosylation on nucleosome structure, in vitro nucleosome remodeling, nuclease accessibility and binding assays were performed. These studies were complemented by chromatin immunoprecipitation assays in resting and LPS-stimulated BV2 cells in order to determine the occupancy of PARP1, nucleosomes and the RelA subunit of NF-κB, as well as ADP-ribosylation, at the Il1β and Tnf promoters. Finally, we determined the effect of pharmacological inhibition of PARP1 enzymatic activity on the LPS stimulation-dependent induction of Il1β and Tnf mRNA., Results: Our results indicate that LPS stimulation induces PARP1 enzymatic activity and histone ADP-ribosylation in the chromatin compartment of BV2 cells. In vitro studies show that nucleosome-bound PARP1 disrupts nucleosome structure histone ADP-ribosylation, increasing the accessibility of nucleosomal DNA. Consistent with this PARP1 is constitutively associated with at the Il1β and Tnf promoters in resting BV2 cells. Upon stimulation with LPS, ADP-ribosylation is observed at these promoters, and this is correlated with increased recruitment of the transcription factor NF-κB, resulting in robust transcription of these inflammatory cytokines. Accordingly, pharmacological inhibition of PARP1 enzymatic activity reduces NF-κB recruitment, and Il1β and Tnf expression in LPS-stimulated microglia., Conclusions: Collectively, our data suggest that PARP1 facilitates inflammatory cytokine expression in microglia by increasing the accessibility of promoter DNA via histone ADP-riboyslation.

Activation of sphingomyelinase (SMase) by extracellular stimuli is the major pathway for cellular production of ceramide, a bioactive lipid mediator acting through sphingomyelin (SM) hydrolysis. Previously, we reported the existence of six forms of neutral pH-optimum and Mg(2+)-dependent SMase (N-SMase) in the membrane fractions of bovine brain. Here, we focus on N-SMase ε from salt-extracted membranes. After extensive purification by 12,780-fold with a yield of 1.3%, this enzyme was eventually characterized as N-SMase2. The major single band of 60-kDa molecular mass in the active fractions of the final purification step was identified as heat shock protein 60 (Hsp60) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis. Proximity ligation assay and immunoprecipitation study showed that Hsp60 interacted with N-SMase2, prompting us to examine the effect of Hsp60 on N-SMase2 and ceramide production. Interestingly, Hsp60 siRNA treatment significantly increased the protein level of N-SMase2 in N-SMase2-overexpressed HEK293 cells. Furthermore, transfection of Hsp60 siRNA into PC12 cells effectively increased both N-SMase activity and ceramide production and increased dopamine re-uptake with paralleled increase. Taken together, these results show that Hsp60 may serve as a negative regulator in N-SMase2-induced dopamine re-uptake by decreasing the protein level of N-SMase2.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is an important regulator of the maturation and function of cells in the granulocyte and macrophage lineages, and also plays a significant role in wound healing. In a previous study, we expressed human GM-CSF in rice cells (rice cell-derived human GM-CSF; rhGM-CSF). The purpose of the present study was to evaluate its effect on wound healing in oral mucositis. Oral mucositis was induced in Syrian hamster cheek pouches by 5-fluorouracil treatment and mechanical scratching. Ulcerated areas were treated from days 3 to 14 with an application of 200 µL saline, or of the same volume of a solution containing 0.04, 0.2, or 1 µg/mL rhGM-CSF. Treatment of hamsters with rhGM-CSF reduced the ulcerated areas of the oral mucosa, compared with the control. Early in the healing process, the mucositis tissue layer of the rhGM-CSF-treated group showed significantly decreased myeloperoxidase activity and increased numbers of proliferating cell nuclear antigen (PCNA)-positive cells. Treatment with rhGM-CSF also affected expression of inflammatory cytokines in the ulcerative mucosal tissue. These results demonstrate the efficacy of plant-produced rhGM-CSF in wound healing and have significant implications for the development of rhGM-CSF as a therapeutic agent for ulcerative oral mucositis.

The packaging of DNA into nucleosomes imposes obstacles on gene transcription, and histone-modifying and nucleosome-remodeling complexes work in concert to alleviate these obstacles so as to facilitate transcription. Emerging evidence shows that chromatin-associated poly(ADP-ribose) polymerase 1 (PARP-1) and its enzymatic activity facilitate inflammatory gene transcription and modulate the inflammatory response in animal models. However, the molecular mechanisms by which PARP-1 enzymatic activity facilitates transcription are not well understood. Here we show that through an intracellular signaling pathway, lipopolysaccharide (LPS) stimulation induces PARP-1 enzymatic activity and the ADP-ribosylation of histones at transcriptionally active and accessible chromatin regions in macrophages. In vitro DNase I footprinting and restriction endonuclease accessibility assays reveal that histone ADP-ribosylation directly destabilizes histone-DNA interactions in the nucleosome and increases the site accessibility of the nucleosomal DNA to nucleases. Consistent with this, LPS stimulation-induced ADP-ribosylation at the nucleosome-occupied promoters of il-1β, mip-2, and csf2 facilitates NF-κB recruitment and the transcription of these genes in macrophages. Therefore, our data suggest that PARP-1 enzymatic activity facilitates gene transcription through increasing promoter accessibility by histone ADP-ribosylation.

The present study examined the effects of Tremella fuciformis (TF) on the learning and memory function and the neural activity in rats with trimethyltin (TMT)-induced memory deficits. The rats were administered saline or TF (TF 25, 50, 100 mg/kg, p.o.) daily for 21 days. The cognitive improving efficacy of TF on the amnesic rats, which was induced by TMT, was investigated by assessing the Morris water maze test and by performing Choline acetyltransferase (ChAT) and cAMP responsive element binding protein (CREB) immunohistochemistry. In order to confirm the underlying mechanisms of the memory enhancing effects of TF, we assessed the neurite outgrowth of PC12 cells. We also administered 18F-fluorodeoxyglucose and performed a PET scan of the frontal lobe. The rats with TMT injection showed impaired learning and memory of the tasks and treatment with TF produced a significant improvement of the escape latency to find the platform in the Morris water maze compared to that of the control group. In the retention test, the TF50 group showed increased time spent around the platform compared to that of the control group. Consistent with the behavioral data, TF50 mg/kg significantly alleviated the loss of ChAT-ir neurons in the hippocampus compared to that of the control group. Treatment with TF significantly increased the CREB positive neurons in the hippocampal CA1 area as compared to that of the control group. In addition, TF treatment (50 mg/kg) increased the glucose uptake approximately sevenfold in the frontal lobe and it significantly promoted neurite outgrowth of the PC12 cells, as compared to that of the controls. These results suggest that TF may be useful for improving the cognitive function via regulation of the CREB signaling pathway and cholinergic system in the hippocampus., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Interactions with cofactors regulate transcriptional activity and also help HOX proteins to achieve the specificity required for transcriptional regulation of target genes. In this study, we describe a novel protein/protein interaction of HOXB7 with poly (ADP-ribose) polymerase-1 (PARP-1) that involves the homeodomain of HOXB7 and the first zinc finger domain of PARP-1. Upon binding to PARP-1, HOXB7 undergoes poly(ADP-ribosyl)altion resulting in a reduction of its transcriptional activity. Since aspartic acid and glutamic acid residues are acceptors of the ADP ribose moiety transferred by PARP-1, deletion of the evolutionarily conserved C-terminal Glu-rich tail of HOXB7 dramatically attenuates ADP-ribosylation of HOXB7 by PARP-1. Further, a mutant of HOXB7 without the Glu-rich tail loses the ability to be negatively regulated by PARP-1 and becomes transcriptionally more active in luciferase reporter assays. Since the homeodomain is highly conserved among HOX proteins, five other HOX proteins were tested. All six showed interaction with, and were poly(ADP-ribosyl)ated by PARP-1. However, among them, this modification altered the DNA binding activity of only HOXA7 and HOXB7. In summary, this study identifies a new interacting partner of HOX proteins. More importantly, this study reveals a novel mechanism whereby polyADP-ribosylation regulates transcriptional activities of HOX proteins such as HOXB7 and HOXA7.

Although it is widely accepted that chronic exposure to arsenite, nickel, chromium and cadmium increases cancer incidence in individuals, the molecular mechanisms underlying their ability to transform cells remain largely unknown. Carcinogenic metals are typically weak mutagens, suggesting that genetic-based mechanisms may not be primarily responsible for metal-induced carcinogenesis. Growing evidence shows that environmental metal exposure involves changes in epigenetic marks, which may lead to a possible link between heritable changes in gene expression and disease susceptibility and development. Here, we review recent advances in the understanding of metal exposure affecting epigenetic marks and discuss establishment of heritable gene expression in metal-induced carcinogenesis.

During an arthroscopic examination for an anterior cruciate ligament (ACL) reconstruction, there is a relatively thick remnant ACL tibial stump attached to the posterior cruciate ligament (PCL) or rarely remained between the femur origin and the tibia insertion. We thought that preservation of the remnant ACL original bundle might promote graft healing or be helpful in preserving the proprioception and function to stabilize the knee. Therefore, we established a remnant preservation procedure without additional instruments during an ACL reconstruction using a bio-cross pin (RIGIDfix system: Mitek, Johnson & Johnson, USA) for the femoral tunnel fixation. The remnant ACL was sutured (usually three stitches) using a suture hook (Linvatec, Largo, FL), and both ends of the sutures were pulled to the far anteromedial (AM) portal. These sutures protected the remnant tissue during the ACL reconstruction because medial traction of these sutures can provide a wide view during the reconstruction. After the femoral and tibial tunnel formation, these sutures were pulled out to the inferior sleeve of the cross pin using a previously inserted wire loop via an inferior sleeve. After graft passage, a superior cross pin was first fixed and tibial fixation was then performed. Finally, inferior cross pin fixation was performed and ties were made at the entrance of the inferior cross pin.

Background: In the symptomatic discoid lateral meniscus, the effectiveness of preoperative magnetic resonance imaging (MRI) is not well documented., Hypothesis: Magnetic resonance imaging classification will provide more information to the surgeon in choosing the appropriate treatment methods with the help of arthroscopic findings., Study Design: Cohort study (diagnosis); Level of evidence, 2., Methods: Sixty-seven patients (82 knees) were reviewed. The preoperative MRI was checked in 76 of 82 knees. The Lysholm and Ikeuchi grading scales were evaluated. Images were analyzed from MRI, and findings were classified into 4 categories: no shift, anterocentral shift, posterocentral shift, and central shift. Tear pattern classifications were based on arthroscopic findings: horizontal tear, peripheral tear, horizontal and peripheral tear, posterolateral corner loss, and others. The correlations between MRI classification tear patterns and surgical methods were analyzed using the chi-square test or the Fisher exact test. The sensitivity, specificity, and accuracy of shift in preoperative MRI-according to the existence of peripheral tear when corroborated with arthroscopy-were also analyzed with the chi-square test. Inter- and intraobserver reliability was statistically analyzed by producing the inter- and intraclass correlation coefficient., Results: The mean preoperative Lysholm score was 77.3 (range, 43-97), and the last follow-up Lysholm score had increased to 96.8 (range, 84-100; P < .001). At last follow-up (100% follow-up), the Ikeuchi grading scale scored 48 knees as excellent, 30 as good, and 4 as fair. According to the MRI classification, 43 knees were no shift; 6, anterocentral shift; 15, posterocentral shift; and 12, central shift. Shift-type knees had a significantly larger number of peripheral tears, and repairs were performed in the shift-type knees (55%) more frequently than in the no-shift-type knees (28%). Among 82 knees, 31 were repaired simultaneously after a central partial meniscectomy., Conclusion: Magnetic resonance imaging classification provides more information to surgeons in choosing the appropriate treatment methods, although the final decision regarding procedure is made during arthroscopy after thorough analysis of the tear.

We analyzed a consecutive series of 23 total hip arthroplasties that had been performed using modular cementless prostheses in 13 patients with a confirmed diagnosis of multiple epiphyseal dysplasia and end-stage osteoarthritis of the hip. The average Harris hip score improved from 40.6 to 93.8 points. Postoperatively, all hips demonstrated favorable alterations in the biomechanical parameters including hip center of rotation, femoral offset, femoral neck length, and limb length. At a mean follow-up of 4.8 years, no hip required revision because of aseptic loosening of the acetabular or femoral component. One patient (1 hip, 4.3%) underwent reoperation for polyethylene wear and osteolysis 8 years after index arthroplasty. This study shows encouraging clinical and radiographic outcomes of modular cementless total hip arthroplasties for this technically difficult condition.

Background: Revision Bankart operations frequently show capsulolabral buttress loss and recurrent soft tissue Bankart lesion. Capsulolabral augmentation is designed to increase glenohumeral stability by 2 separate mechanisms: deepening the glenoid concavity and reducing capsular laxity. This is accomplished by shifting the capsule to buttress the glenoid labrum., Hypothesis: A retained capsulolabral buttress may show loss of height and slope at a certain period after surgery, regardless of stability. Thus, the authors wanted to confirm the importance of an intraoperative establishment of capsulolabral buttress in terms of stability., Study Design: Case-control study; Level of evidence, 3., Methods: Arthroscopically repaired Bankart lesions in 21 consecutive shoulders that showed no frank dislocation were evaluated using axial and oblique coronal T2-weighted magnetic resonance imaging at 3 timepoints (preoperative period, average postoperative week 6 and a nearly full range of motion recovery, and postoperative month 6 with a return to daily activity). The authors measured 2 parameters (height and slope) on axial (mainly capsulolabral containment) and oblique coronal images (mainly inferior glenohumeral ligament) at the anteroinferior portion of the glenoid (5 mm above the most inferior anchor). In addition, they compared the above-mentioned parameters at postoperative month 6 by magnetic resonance imaging in 21 controls and in 21 patients whose instability recurred after surgery (not included in the prospective study)., Results: There was a significant increase between the preoperative period and postoperative week 6 in all 4 parameters (P < .0001). There was also a significant increase between the preoperative period and postoperative month 6 in all 4 parameters (P < .0001). However, no statistically significant difference was observed between postoperative week 6 and postoperative month 6 in all 4 parameters (P > .1). Furthermore, significant differences were observed between normal controls and patients with recurrent instability (P < .001) and between the authors' cases and patients with recurrent instability not in the study (P < .001). However, no difference was observed between their cases and normal shoulders (P > .1)., Conclusion: After suture anchor Bankart repair, initial capsulolabral buttress property was maintained at 6 months postoperatively. Furthermore, the buttress was more prominent in stable and normal shoulders than in recurrent instability shoulders. Therefore, the authors believe that the establishment of a capsulolabral buttress is meaningful during Bankart repair.

We describe a new and effective arthroscopic physeal sparing repair of the tibial eminence avulsion fracture using all an inside repair technique. The treatment of ACL avulsion is controversial, especially in skeletally immature patients, with concerns about physeal damage, and a more reliable way of fixation is still being pursued for small or comminuted fragments. Screw fixation and suture cerclage has some limitations, especially in the small fragment or skeletally immature patients. We fixed avulsion fragment using all inside repair between the distal portion of the ACL and transverse ligament and periosteum. A crescent suture hook loaded with NO. 0 PDS is introduced and the suture hook pierces the transverse intermeniscal ligament and periosteum. The half length of the PDS is now advanced out through the hook and the end is brought out to the anterolateral portal. With the suture hook located intra-articularly and loaded with half the length of the original PDS, the suture hook repierces the transverse intermeniscal ligament at 5 mm on the side and the remaining half length of PDS is now advanced out through the hook and the end is brought out to the anterolateral portal. After that procedure, the suture hook loaded with NO. 0 absorbable Maxon is introduced through the anteromedial portal for the role of shuttle relay. The suture hook pierces the ACL just above the superior border of the avulsion fragment, the Maxon is now advanced out through the hook and the end is brought out to the anterolateral portal. Subsequently, the suture hook is removed and a suture retriever is introduced through the anterolateral portal. PDS and Maxon are held together and retrieved out of the anterolateral portal by the suture retriever at the same time. Our technique has advantages in small comminuted fractures and skeletally immature patients.

Purpose: This study was undertaken to document the clinical results and technical aspects of arthroscopic partial meniscectomy in conjunction with peripheral tear repair for the treatment of symptomatic discoid lateral meniscus in children., Methods: From June 1998 to May 2005, the senior author (J.H.A.) performed arthroscopic surgery on 77 children (89 knees) with symptomatic discoid lateral meniscus. Of these patients, we retrospectively studied 23 patients (28 knees) with a peripheral tear that was treated by partial central meniscectomy in conjunction with peripheral suture repair. Mean age at operation was 9.0 years (range, 4 to 15 years), and the mean follow-up period was 50.9 months (range, 24 to 94 months). Arthroscopic findings were categorized into 3 types in terms of peripheral rim stability and tear site: (1) meniscocapsular junction (MC), anterior horn type (MC-A type); (2) MC, posterior horn type (MC-P type); and (3) posterolateral corner (PLC) loss type. These 3 types needed different arthroscopic techniques for saucerization with repair. Clinical results were evaluated using Lysholm knee scores and Hospital for Special Surgery (HSS) scores preoperatively and at final follow-up., Results: All patients were able to return to their previous life activities with little or no limitation, and no reoperation was required after an average follow-up of 51 months. Mean Lysholm knee scores improved from 78.5 (range, 69 to 89) preoperatively to 95.5 (range, 85 to 100) at the final follow-up (P < .0001), and the mean HSS score improved from 80.3 (range, 69 to 89) preoperatively to 95.9 (range, 90 to 100) at the final follow-up (P < .0001)., Conclusions: We believe that the described arthroscopic partial meniscectomy in conjunction with the meniscal repair of the peripheral tear are effective for treating children with a symptomatic discoid lateral meniscus., Level of Evidence: Level IV, therapeutic case series.

Each arthroscopic portal to the knee has a blind area that cannot be inspected directly. In particular, visualization of the posterior compartment is difficult to access. Although arthroscopic procedures for the posterior compartment of the knee joint have been developed through posteromedial, posterolateral and posterior trans-septal portal, the popliteal bursa remains as an area that is difficult to access and manipulate. We report a surgical procedure that can examine one of the blind spots in knee arthroscopy, popliteal bursa.

Posterior knee discomfort and recurrent effusion of the left knee occurred in a 49-year-old man without a history of specific trauma. Magnetic Resonance Imaging (MRI) and an arthroscopic examination revealed a soft tissue mass arising from the posterolateral capsule. The microscopic diagnosis was a fibroma, which is a rare entity in this location. To the best of our knowledge, only four cases of fibroma in the knee have been reported. It was reported that more than 99% of fibromas arise from tendon sheaths or tendons. They sometimes present a diagnostic problem due to their relative rarity in this location and obscure histological features. Fibroma should be included in a differential diagnosis of a soft tissue tumor arising from the knee joint. However, an arthroscopic excision was curative in our case.

We describe the arthroscopic management of the posterior capsule tear using posterior trans-septal portal. This technique is usually used in acute cases where a torn capsule is found but we can also use this technique for reefing of stretched capsule by refreshing the injured capsule. When arthroscopic ligament reconstruction accompanies postero-medial or postero-lateral capsular insufficiency, using the posterior trans-septal portal could ensure better visualization of the capsule and a subsequent more accurate management of the capsule. Since it is helpful in lessening the instability, it could contribute to achieving successful clinical results although this is not a mighty procedure.

The aims of this study were to quantify the angle and placement of an anterior cruciate ligament (ACL) grafted with a single incision ACL reconstruction technique using postoperative magnetic resonance imaging (MRI), and to compare the results with those with a native ACL. Between February 1996 and May 2004, 96 consecutive patients, who had undergone postoperative MRI of the knee followed by an arthroscopically assisted ACL reconstruction with either a hamstring tendon or bone-patellar tendon-bone (BTB) autograft, were enrolled in this study. The femoral tunnel was drilled using the transtibial technique. The patients were divided into two groups; the hamstring tendon graft group (group H; 50 patients) and the BTB graft group (group B; 46 patients). All the patients including both groups in this study underwent postoperative MRI and were followed up for a minimum of 2 years. The control group (group C) consisted of 50 patients whose meniscus tear had been operated on by arthroscopy and whose ACL was intact. The orientation of the ACL ligament or graft was measured using three different methods: the sagittal ACL angle, the ACL-Blumensaat line angle, and the coronal ACL angle. The mean sagittal ACL angle in group C (58.7 +/- 3.8 degrees ) was significantly lower than in groups H (64.6 +/- 4.2 degrees ) and B (71.3 +/- 6.0 degrees ). The mean ACL-Blumensaat line angle in group C (8.6 +/- 3.6 degrees ) was also significantly lower than in groups H (12.8 +/- 5.2 degrees ) and B (18.0 +/- 5.3 degrees ). The mean coronal ACL angle in group C (65.9 +/- 4.4 degrees ) was lower than that in groups H (73.5 +/- 2.4 degrees ) and B (75.2 +/- 2.9 degrees ). The grafted ACL of the hamstring tendon and BTB grafts on the postoperative MRI showed a significant vertical angle in the coronal and sagittal plane compared with the native ACL. In the sagittal plane, the hamstring tendon graft was positioned more obliquely than the BTB graft, which had a larger angle of the tibial tunnel, in an attempt to prevent a graft-tunnel mismatch. The postoperative MRI study showed that the more horizontally the angle of the tibial tunnel can be placed in a single incision ACL reconstruction, the more efficiently it can produce a graft closer to the native ACL.

The government has launched a program to promote the research on acupuncture and moxibustion since 1972. It was mainly through the join effort of the National Science Council and Department of health that funds were made available to major medical institutions in Taiwan for research in the theoretical and clinical application of acupuncture-moxibustion. Moreover, the emphasis has been laid on the application of modern medical knowledge and technology to traditional acupuncture-moxibustion in order to explore the mechanism of acupuncture analgesia and to determine the effectiveness of acupuncture-moxibustion in the treatment of diseases. The efforts of such studies have resulted in conferences and symposia at the national and/or international levels from 1970s to 1980s. Development and progress of acupuncture-moxibustion research in Taiwan since 1970s are reported and discussed in the article.

Few cases have been reported in which the femoral interference screw has migrated into the posterior compartment after an ACL reconstruction. It usually requires removal, because it leads usually to mechanical symptom. However, the arthroscopic removal of a screw is a technically demanding procedure, especially in the case of the femoral interference screw that has migrated into the femoral notch (posterior compartment), an intact integrated ACL graft or one that is encapsulated around the screw. We present a case in which a displaced femoral interference screw migrated within the posterior compartment 11 years postoperatively, after the graft had been incorporated at the femoral site. Although it is often technically challenging, through the use of a posterior trans-septal portal, we can successfully remove a displaced femoral interference screw even in the most difficult locations in the posterior compartment.

We investigated the neuritogenic effects of Tremella fuciformis (TF), which has been valued in traditional Chinese medicine as a remedy with nutritive and tonic actions, on PC12h cells. The cognitive improving effects of TF on scopolamine-induced (2 mg/kg, s.c.) amnesia in rats were also evaluated with using the Morris water maze task and by performing choline acetyltransferase (ChAT) immunohistochemistry. The water extract of TF (0.01-1 microg/ml) promoted neurite outgrowth of the PC12h cells in a dose dependent manner. TF was highly efficient at the concentration range of 0.1-1 microg/ml. Oral daily treatment with TF (100 or 400 mg/kg) for 14 consecutive days significantly reversed the scopolamine-induced deficit in learning and memory, and it alleviated decrease in cholinergic immunoreactivity induced by scopolamine in the medial septum and hippocampus. The results demonstrate that the promotion of neuritogenesis in neuronal culture cells by TF water extract is related with its activity for improving the performance of rats on a spatial learning and memory task. Moreover, the impairments of spatial learning and memory may be attributable to the decrease in activation of the septohippocampal cholinergic system and that TF ameliorated learning and memory deficits partly through its increasing the central cholinergic activity. Therefore, TF could represent a potentially useful agent that is able to improve the function of impaired cognitive processes.

We examined the neuroprotective and neurotrophic effects of Tremella fuciformis. The neurotrophic effects of the hot water extract of T. fuciformis was evaluated by microscopically monitoring its potency to induce neurite outgrowth in PC12h cells. The hot water extract of T. fuciformis promoted neurite outgrowth in PC12h cells in this study, superior to other natural substances which was reported previously. When cells were treated with the hot water extract of T. fuciformis prior to β-amyloid peptide treatment (active domain of A peptide 25~35 treated), toxicity was significantly diminished (p<0.01). These results suggest that T. fuciformis might potentially be used as a precautionary agent in neurodegenerative disease, such as Alzheimer's disease, etc.

We report the first observation of a charmoniumlike state recoiling from the J/psi in the inclusive process e+e- -->J/psi+anything at a mass of (3.943+/-0.006+/-0.006) GeV/c{2}. We also observe the decay of this state into D*D[over ] and determine its intrinsic width to be less than 52 MeV/c{2} at the 90% C.L. These results are obtained from a 357 fb{-1} data sample collected with the Belle detector near the Upsilon(4S) resonance, at the KEKB asymmetric-energy e+e- collider.

Homeobox genes encode transcription factors which function in body axis patterning in the developing embryo. Recent evidence suggests that the maintenance of specific HOX expression patterns is necessary for regulating the homeostasis of adult tissues as well. In this study, HOXB7 transformed human mammary epithelial cells, MCF10A, to grow in minimally supplemented medium, to form colonies in Matrigel, and display resistance to ionizing radiation. Searching for protein partners of HOXB7 that might contribute to resistance to ionizing radiation, we identified four HOXB7-binding proteins by GST pull-down/affinity chromatography and confirmed their interactions by coimmunoprecipitation in vivo. Interestingly, all four HOXB7-binding proteins shared functions as genomic caretakers and included members of the DNA-dependent protein kinase holoenzyme (Ku70, Ku80, DNA-PK(cs)) responsible for DNA double-strand break repair by nonhomologous end joining pathway and poly(ADP) ribose polymerase. Exogenous and endogenous expression of HOXB7 enhanced nonhomologous end joining and DNA repair functions in vitro and in vivo, which were reversed by silencing HOXB7. This is the first mechanistic study providing definitive evidence for the involvement of any HOX protein in DNA double-strand break repair.

The continuous production of the CXC ligand 1 (CXCL1) chemokine by melanoma cells is a major effector of tumor growth. We have previously shown that the constitutive expression of this chemokine is dependent upon transcription factors nuclear factor-kappa B (NF-kappaB), stimulating protein-1 (SP1), high-mobility group-I/Y (HMGI/Y), CAAT displacement protein (CDP) and poly(ADP-ribose) polymerase-1 (PARP-1). In this study, we demonstrate for the first time the mechanism of transcriptional regulation of CXCL1 through PARP-1 in melanoma cells. In its inactive state, PARP-1 binds to the CXCL1 promoter in a sequence-specific manner and prevents binding of NF-kappaB (p65/p50) to its element. However, activation of the PARP-1 enzymatic activity enhances CXCL1 expression, owing to the loss of PARP-1 binding to the CXCL1 promoter, accompanied by enhanced binding of p65 to the promoter. The delineation of the role of NF-kappaB-interacting factors in the putative CXCL1 enhanceosome will provide key information in developing strategies to block constitutive expression of this and other chemokines in cancer and to develop targeted therapy.

We report evidence for the exclusive two-body charmless hadronic B meson decay B-->eta'pi, and improved measurements of B-->eta'K. The results are obtained from a data sample of 386x10(6) BB pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure B(B+-->eta'pi+)=[1.76(-0.62)(+0.67)(stat)(-0.14)(+0.15)(syst)]x10(-6) and B(B0-->eta'pi0)=[2.79(-0.96)(+1.02)(stat)(-0.34)(+0.25)(syst)]x10(-6). We also find the ratio of B(B+-->eta'K+)/B(B0-->eta'K0)=1.17+/-0.08(stat)+/-0.03(syst) and measure the direct CP asymmetries for the charged modes.

We report results on a Dalitz analysis of three-body charmless B+/- --> K+/-pi+/-pi+/- decay including searches for direct CP violation. We report the first observation of the decay B+/- --> f2(1270)K+/- with a statistical significance above 6sigma. We also observe first evidence for large direct CP violation in the B+/- --> rho(770)0K+/- channel. The results are obtained with a data sample that contains 386 10(6) BB pairs collected at the Y(4s) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.

The Collins effect connects transverse quark spin with a measurable azimuthal dependence in the yield of hadronic fragments around the quark's momentum vector. Using two different reconstruction methods, we find evidence of statistically significant azimuthal asymmetries for charged pion pairs in e(+)e(-) annihilation at a center-of-mass energy of 10.52 GeV, which can be attributed to a transverse polarization of the primordial quarks. The measurement was performed using a sample of 79 x 10(6) hadronic events collected with the Belle detector.

We report the observation of the flavor-changing neutral current process b-->dgamma using a sample of 386 x 106 B meson pairs accumulated by the Belle detector at the KEKB e+e- collider. We measure branching fractions for the exclusive modes B--->rho-gamma, B0rho0gamma, and B0omegagamma. Assuming that these three modes are related by isospin, we find B(B-->(rho,gamma)gamma)=[Formula: See Text] with a significance of 5.1sigma. This result is used to determine the ratio of Cabibbo-Kobayashi-Maskawa matrix elements /Vtd/Vts/ to be [Formula: See Text].

We report the results of a search for D0-D0 mixing in D0 --> K+ pi- decays based on 400 fb(-1) of data accumulated by the Belle detector at KEKB. Both assuming CP conservation and allowing for CP violation, we fit the decay-time distribution for the mixing parameters x and y, as well as for the parameter R(D), the ratio of doubly Cabibbo-suppressed decays to Cabibbo-favored decays. The 95% confidence level region in the (x'2,y') plane is obtained using a frequentist method. Assuming CP conservation, we find x'2 < 0.72 x 10(-3) and -9.9 x 10(-3) < y' < 6.8 x 10(-3) at the 95% confidence level; these are the most stringent constraints on the mixing parameters to date. The no-mixing point (0,0) has a confidence level of 3.9%. Assuming no mixing, we measure R(D) = (0.377 +/- 0.008 +/- 0.005)%.

We report on a search for new resonant states in the process gamma gamma --> DD. A candidate C-even charmonium state is observed in the vicinity of 3.93 GeV/c2. The production rate and the angular distribution in the gamma gamma center-of-mass frame suggest that this state is the previously unobserved chi(c2)', the 2(3)P2 charmonium state.

The pathophysiology of Huntington's disease reflects actions of mutant Huntingtin (Htt) (mHtt) protein with polyglutamine repeats, whose N-terminal fragment translocates to the nucleus to elicit neurotoxicity. We establish that the nuclear translocation and associated cytotoxicity of mHtt reflect a ternary complex of mHtt with GAPDH and Siah1, a ubiquitin-E3-ligase. Overexpression of GAPDH or Siah1 enhances nuclear translocation of mHtt and cytotoxicity, whereas GAPDH mutants that cannot bind Siah1 prevent translocation. Depletion of GAPDH or Siah1 by RNA interference diminishes nuclear translocation of mHtt.

Poly(ADP-ribose) polymerase 1 (PARP-1) activity is detected in both neuronal and nonneuronal cells in the CNS, and excessive PARP-1 activity is known to be detrimental to tissue because of the cellular energy loss. Accordingly, PARP-1-deficient (PARP-1(-/-)) mice have been shown to be resistant to cerebral ischemia and several forms of inflammation. Recently, PARP-1 in glial cells has been shown to mediate the expression of proinflammatory genes in response to inflammatory stimuli by, in part, enhancing cognate DNA-binding capacities of transcription factors such as NF-kappaB and activator protein 1. Here, we demonstrate an additional mechanism whereby a significant reduction of proinflammatory gene expression such as IL-1beta, tumor necrosis factor alpha, and inducible nitricoxide synthase in PARP-1(-/-) glial cells is linked to defective inflammatory stimuli-induced p38MAPK-mediated phosphorylation of ATF-2 and cAMP-response element-binding protein and phosphorylation of NF-kappaB p65. Importantly, an inflammatory stimuli-induced p38MAPK activation is impaired in PARP-1(-/-) glial cells in a signaling pathway- and cell/tissue type-specific manner. These findings indicate that PARP-1 is an essential host factor among factors that actively mediate excessive production of proinflammatory molecules in glial cells, which may in turn contribute to the initiation of neuronal injuries.