Radiolucent rings around bioabsorbable anchors after rotator cuff repair are not associated with clinical outcomes.

PURPOSE: Various researchers have observed small areas of osteolysis after using bioabsorbable anchors in shoulder surgeries. The purpose of this study is to determine whether radiographic perianchor radiolucent rings after rotator cuff repair are associated with the failure of repair and also assess their clinical implications. Further, the most frequent location of the radiolucent rings in the double-row suture bridge configuration was also assessed. METHODS: One hundred and twenty-nine consecutive patients who underwent arthroscopic rotator cuff repair by suture bridge technique were retrospectively evaluated radiographically and clinically. The number and size of the rings that appeared at each follow-up were recorded. Also, the locations of each ring were recorded as anterior, middle or posterior, and medial or lateral according to the construct of the anchors used for suture bridge technique. The size of the tear, the number of anchors used and age of the patients were compared. Re-tear rates according to ultrasound examinations were also analyzed. RESULTS: After rotator cuff repair, the mean American Shoulder and Elbow Surgeons (ASES) score increased from 46.7 to 88.0 and the overall re-tear rate was 8.5% (11 cases). Seventy-three patients (56.6%) showed RR (total number of 99 rings) at least once during the course of their follow-up and the rings appeared at a mean period of 18.2 months after surgery. Mean size of the rings initially was 5.6 mm and the rings increased or decreased in mean size of 0.4 mm during mean follow-up of 37 months. No correlation was seen with the number of RRs and the rate of re-tears, number of anchors, size of tears, and clinical outcome as determined by the ASES score. Radiolucent ring measurement reproducibility was confirmed by independent, repeated measurements. The rings appeared mostly at anteromedial anchors (75 rings, 75.8%) and the authors suggest that mechanical factors may play a role for the cause of radiolucent rings. CONCLUSIONS: The number and the size of RRs around bioabsorbable anchors after rotator cuff repair do not appear to adversely affect the healing and clinical outcome of ARCR. Most radiolucent rings appeared at anteromedial anchors, indicating that mechanical factors may play a role for the radiolucencies. LEVEL OF EVIDENCE: Case series, level IV.

Epigenetic inactivation of transforming growth factor-ß1 target gene HEYL, a novel tumor suppressor, is involved in the P53-induced apoptotic pathway in hepatocellular carcinoma.

AIM: Hairy/enhancer-of-split related with YRPW motif-like (HEYL) protein was first identified as a transcriptional repressor. It is a downstream gene of the Notch and transforming growth factor-ß pathways. Little is known about its role in the pathogenesis of hepatocellular carcinoma (HCC). METHODS: Eighty surgically resected paired HCC and adjacent non-cancerous tissues were analyzed for HEYL expression by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). HCC cells were transfected with pHEYL-EGFP vector to overexpress the HEYL gene or infected with specific shHEYL lentiviral vector to silence HEYL gene expression. HEYL expressional analysis and functional characterization were assessed by 3-(4 5-dimethylthiazol-2-yl)-2 5-diphenyltetrazolium bromide assays, flow cytometry, RT-qPCR, western blotting and methylation-specific PCR. RESULTS: We determined that HEYL expression was inactivated in more than 75% of HCC. In addition, overexpression of HEYL in SK-Hep 1 cells caused apoptosis by the cleavage of caspase 3 and poly (ADP-ribose) polymerase. We discovered that HEYL apoptosis was preceded by serine 15 phosphorylation and accumulation of P53. Molecular analysis revealed that HEYL overexpression led to increased p16, p19, p21, p27 and Bad protein expression, and reduced c-Myc, Bcl-2 and Cyclin B1 expression. Epigenetic silencing of HEYL expression by DNA hypermethylation in HCC directly correlated with loss of HEYL expression in HCC. CONCLUSION: HEYL is frequently downregulated by promoter methylation in HCC. HEYL may be a tumor suppressor of liver carcinogenesis through upregulation of P53 gene expression and activation of P53-mediated apoptosis.

Activation of α-diazocarbonyls by organic catalysts: diazo group acting as a strong N-terminal electrophile.

For the first time α-diazocarbonyls have been used as highly active N-terminal electrophiles in the presence of bicyclic amidine catalysts. The CN bond-forming reactions of active methylene compounds as C nucleophiles with α-diazocarbonyls as N-terminal electrophiles proceed quickly under ambient conditions, in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), because of the formation of the reactive N-terminal electrophilic intermediates. DBU activates both the active methylene and α-diazocarbonyl. Importantly, this reaction is general for both active methylenes and α-diazocarbonyls, and the activation mode will lead to new synthetic applications of α-diazocarbonyls.

Expression and characterization of recombinant gallinacin-9 and gallinacin-8 in Escherichia coli.

Gallinacins (Gal) are antimicrobial peptides that play significant roles in innate immunity in chickens. Two Gal genes--Gal-8 and Gal-9--were cloned and sequenced from chicken liver and tongue, respectively, by reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, the mRNA expression of these genes has been demonstrated across a panel of chicken tissues. It was demonstrated that Gal-9 mRNA was highly expressed in the tongue and small intestine and moderately expressed in the chicken proventriculus, lung, liver, heart, spleen, and thymus. However, Gal-8 mRNA was highly expressed in the chick small intestine and liver, and moderately expressed in the chick tongue, and lung. The recombinant fusion proteins containing Gal-9 or Gal-9 and Gal-8, namely rGal-9 and rGal-9-Gal-8, were produced and purified, respectively. Both rGal-9 and rGal-9-Gal-8 were expressed as insoluble bodies and exhibited the expected antimicrobial activity against Escherichia coli and pathogenic Streptococci suis CAB strain, as determined by the measurement of the inhibition zone and a liquid growth inhibition assay.

P2X7 receptor is involved in lung injuries induced by ischemia-reperfusion in pulmonary arterial hypertension rats.

Pulmonary arterial hypertension (PAH) is a progressive disease that ultimately leads to right heart failure and death. Current strategies are ineffective to prevent and cure PAH, especially in those who undergo cardiopulmonary bypass. P2 × 7 receptors (P2 × 7Rs) have been implied to participate in the pathogenesis of PAH and injuries induced by ischemia-reperfusion (IR). In the present study, we aimed to assess the potential therapeutic effects of anti-P2 × 7Rs on PAH and IR-induced lung injuries in rats and explore their underlying cellular and molecular mechanisms. In the present study, we have successfully established rat models with PAH and/or lung IR injuries. Immunohistochemical staining, western blot, and polymerase chain reaction were performed to detect the P2 × 7R expression in these models; P2 × 7R-specific inhibitor, Brilliant Blue G (BBG), was used to antagonize P2 × 7R, and enzyme-linked immunosorbent assay was used to help evaluate the P2 × 7R-mediated function in PAH with or without IR. Moreover, BBG, SB203580 (p38/MAPK inhibitor), and CD39 (adenosine triphosphate hydrolase) were applied to explore the inner signal pathway in vitro and in vivo. Our findings showed that P2 × 7R was involved in the development of PAH. By applying BBG, we have shown that the severity of PAH and IR was ameliorated through reducing the release of proinflammatory cytokines. Moreover, our results in vitro and in vivo indicated that P2 × 7R regulated the release of inflammatory mediators by the p38/MAPK signal pathway. Most important, CD39 showed the most dominant potential in improving inflammation in lung injuries caused by PAH and IR. In conclusion, the inhibition of P2 × 7R could effectively attenuate inflammation in lung injuries caused by PAH and IR in rats by reducing proinflammatory cytokines through regulating the p38/MAPK pathway.

Gold/Copper-Co-catalyzed Tandem Reactions of 2-Alkynylanilines: A Synthetic Strategy for the C2-Quaternary Indolin-3-ones.

A new strategy for direct and highly efficient synthesis of 2,3'-bisindolin-3-ones has been developed via a gold/copper-co-catalyzed tandem reactions of 2-alkynylanilines using TBHP as the terminal oxidant and oxygen-atom source. The single-step process involves a novel tandem intermolecular nucleophilic addition, intramolecular cyclization/oxidative cross-dehydrogenative coupling where up to four new bonds and two indole rings were created simultaneously in one-pot manner. The reaction features a broad substrate scope, good functional group tolerance, and high atom-economy.

BTG2 inhibits the proliferation and metastasis of osteosarcoma cells by suppressing the PI3K/AKT pathway.

B cell translocation gene 2 (BTG2) has been reported to be a potential tumor suppressor in many types of tumors. However, the roles and molecular mechanisms of BTG2 in osteosarcoma progression are still unknown. In this study, we investigated the role of BTG2 in proliferation and metastasis of osteosarcoma and the underlying mechanism. BTG2 expression levels were measured in fresh osteosarcoma tissues and cell lines. The effects of BTG2 on cell proliferation, migration and invasion were explored by MTT, transwell assays, western blot, and in vivo tumorigenesis in nude mice. We found that BTG2 was down-regulated in human osteosarcoma tissues and cell lines. Overexpression of BTG2 inhibited the proliferation and migration/invasion of human osteosarcoma cells in vitro, it also markedly inhibited xenograft tumor growth in vivo. Furthermore, BTG2 significantly decreased the expression of phosphorylated PI3K and AKT in osteosarcoma cells. Taken together, our data indicate that BTG2 might suppress the tumor growth and metastasis via PI3K/AKT signaling pathway, implying that BTG2 may serve as a potential molecular target for the treatment of osteosarcoma.

Copper(II)-catalyzed oxidative [3+2] cycloaddition reactions of secondary amines with α-diazo compounds: a facile and efficient synthesis of 1,2,3-triazoles.

A novel copper-catalyzed [3+2] cycloaddition reaction of secondary amines with α-diazo compounds has been developed via a cross-dehydrogenative coupling process. The reaction involves a sequential aerobic oxidation/[3+2] cycloaddition/oxidative aromatization procedure and provides an efficient method for the construction of 1,2,3-triazoles in a single step in an atom-economic manner from readily available starting materials under very mild conditions.

A base-catalyzed cycloisomerization of 5-cyano-pentyne derivatives: an efficient synthesis of 3-cyano-4,5-dihydro-1H-pyrroles.

A base-catalyzed cycloisomerization of 5-cyano-pentyne bearing a terminal alkyne group has been developed under metal-free conditions. This reaction involves a tandem process providing efficient access to 3-cyano-4,5-dihydro-1H-pyrroles in good to excellent yields in an atom-economic manner with 1,3-cyano migration as the key transformation.

Base-catalyzed bicyclization of dialkyl glutaconates with cinnamoylacetamides: a synthetic strategy for isoquinolinedione derivatives.

We report here that polysubstituted dihydroisoquinolones and isoquinolones can be constructed by the one-pot reaction of the readily available acyclic α,ß-unsaturated carbonyl precursors and dialkyl glutaconates under mild basic conditions (1-45 min for the former vs. 1-6 h for the latter) via the domino process involving [3+3] annulation/intramolecular aza-cyclization.

Effects of denaturation and amino acid modification on fluorescence spectrum and hemagglutinating activity of Hericium erinaceum Lectin.

A sialic acid-binding lectin (Hericium erinaceum lectin, HEL), isolated from fresh fruiting bodies of Hericium erinaceum, was treated with various temperature and pH to investigate its fluorescence spectra and hemagglutinating activity. It was found that the hemagglutinating activity of HEL was relatively steady below 60 degrees and at pH from 6 to 11, and the change of hemagglutinating activity was relative to the change of hydrophobic areas where tryptophan residues located. In fluorescence quenching study of HEL by acrylamide and KI, it was indicated that nearly all the tryptophan residues of HEL located on the surface of the molecule, and most of them were in hydrophobic areas or negatively charged areas. Chemical modification of HEL proved that there were about twelve tryptophan residues in a HEL molecule and all of them were located on the surface or in the shallow groove of the molecule, and eight of them were essential for hemagglutinating activity; aspartic acid or glutamic acid residues were involved in maintaining the crucial conformation of activity center and made great contribution to the hemagglutinating activity of HEL, but they could not touch the sialic acid molecule directly; tyrosine residues also played a role in the hemagglutinating activity of HEL; while arginine, serine, threonine, histidine residues had no effect on the hemagglutinating activity of HEL.