A new peptide, VD11, promotes structural and functional recovery after spinal cord injury.

The regenerative capacity of the central nervous system is very limited and few effective treatments are currently available for spinal cord injury. It is therefore a priority to develop new drugs that can promote structural and functional recovery after spinal cord injury. Previous studies have shown that peptides can promote substantial repair and regeneration of injured tissue. While amphibians have a pronounced ability to regenerate the spinal cord, few studies have investigated the effect of amphibian spinal cord-derived peptides on spinal cord injury. Here we report for the first time the successful identification and isolation of a new polypeptide, VD11 (amino acid sequence: VDELWPPWLPC), from the spinal cord of an endemic Chinese amphibian (Odorrana schmackeri). In vitro experiments showed that VD11 promoted the secretion of nerve growth factor and brain-derived neurotrophic factor in BV2 cells stimulated with lipopolysaccharide, as well as the proliferation and synaptic elongation of PC12 cells subjected to hypoxia. In vivo experiments showed that intravertebral injection of VD11 markedly promoted recovery of motor function in rats with spinal cord injury, alleviated pathological damage, and promoted axonal regeneration. Furthermore, RNA sequencing and western blotting showed that VD11 may affect spinal cord injury through activation of the AMPK and AKT signaling pathways. In summary, we discovered a novel amphibian-derived peptide that promotes structural and functional recovery after spinal cord injury.

Long non-coding RNA SNHG1 regulates rheumatoid synovial invasion and proliferation by interaction with PTBP1.

Fibroblast-like synoviocytes (FLSs) in rheumatoid arthritis (RA) present proliferative and aggressive cell phenotype. RA-FLSs are the essential effector cells that lead to symptoms like synovial inflammation and joint destruction. Currently, the cause of RA-FLSs involving in the pathological process of RA remains unknown. Accumulate researches have demonstrated that lncRNAs may play a critical role in regulating the biological behaviors of RA-FLSs, but the mechanism is still unclear. Here, we found that lncRNA small nucleolar RNA host gene 1 (SNHG1) is up-regulated in RA-FLSs compared with FLSs from trauma arthritis and osteoarthritis patients. The results suggest that SNHG1 in RA-FLSs helps to sustain the cellular functions of proliferation, migration and invasion. Furthermore, the regulation mechanism depends on the interaction between SNHG1 and polypyridine tract-binding protein 1 (PTBP1). This interaction influences PTBP1 expression that participates in the regulation of RA-FLSs biological behaviors. Our results suggest that up-regulated SNHG1 of RA-FLSs may contribute to synovial aggression and disease progression in RA and be favourable for RA treatment target RA-FLSs.

Natural allelic variations provide insights into host adaptation of Phytophthora avirulence effector PsAvr3c.

Filamentous pathogens, such as fungi and oomycetes, secrete avirulence (AVR) effectors that trigger plant immune responses and provide striking examples of host adaptations. Avr effector genes display different types of allelic variations, including deletions, epigenetic silencing and sequence polymorphisms, to avoid detection. However, how effector sequence polymorphisms enable pathogens to dodge host immune surveillance remains largely unknown. PsAvr3c is a Phytophthora AVR gene that is recognized by soybean carrying Rps3c. PsAvr3c natural alleles display a rich diversity of single nucleotide polymorphisms in field isolates. We combined both site-directed mutagenesis and population sequence surveys to identify a serine substitution of glycine at position 174 in PsAvr3c that resulted in evasion of Rps3c-mediated soybean immunity. The S174G substitution did not affect the nuclear localization of PsAvr3c in planta, which is required to activate Rps3c, but it significantly impaired the binding affinity of PsAvr3c with a previously identified spliceosome-associated protein GmSKRPs. Silencing GmSKRPs specifically impaired PsAvr3c-triggered cell death in Rps3c soybean. This study uncovered a plant Phytophthora pathogen that adapted to a resistant plant through a key amino acid mutation and subsequently reduced the binding affinity with a plant immune regulator to evade host resistance.

Smoothened Regulates Migration of Fibroblast-Like Synoviocytes in Rheumatoid Arthritis via Activation of Rho GTPase Signaling.

Fibroblast-like synoviocytes (FLSs) acquire aggressive phenotypes characterized with enhanced migration abilities and inherent invasive qualities in rheumatoid arthritis (RA). Smoothened (Smo) is a key component of sonic hedgehog (Shh) signaling and contributes to tumor cell invasion and metastasis. The objective of this study is to investigate the role of Smo in the modulation of cell migration and explore the underlying molecular mechanism(s). FLSs were isolated from RA synovium. Shh levels were regulated by a Smo agonist (purmorphamine), Smo antagonist (KAAD-cyclopamine), or small interfering RNA targeting the Smo gene (Smo-siRNA) in RA-FLSs. Expression of Smo was detected by real-time PCR and western blot analysis. Cell migration was examined by Transwell assay and activation of Rho GTPases was measured by pull-down assays. Incubation with purmorphamine resulted in a significant increase of cell migration and activation of Rho GTPase signaling compared to controls (P < 0.05). However, treatment with KAAD-cyclopamine or transfection with Smo-siRNA suppressed migration of RA-FLSs and showed an inhibitory effect of Rho GTPase signaling. Together, these results suggest that Smo plays an important role in RA-FLSs migration through activation of Rho GTPase signaling and may contribute to progression of RA, thus, targeting Shh signal may have a therapeutic potential in patients with RA.

DEPTOR expression negatively correlates with mTORC1 activity and tumor progression in colorectal cancer.

The mammalian target of rapamycin (mTOR) signaling pathway is upregulated in the pathogenesis of many cancers, including colorectal cancer (CRC). DEPTOR is an mTOR inhibitor whose expression is negatively regulated by mTOR. However, the role of DEPTOR in the development of CRC is not known. The aim of this study was to investigate the expression of DEPTOR and mTORC1 activity (P-S6) in a subset of CRC patients and determine their relation to tumor differentiation, invasion, nodal metastasis and disease-free survival. Here, Immunohistochemical expression of P-S6 (S235/236) and DEPTOR were evaluated in 1.5 mm tumor cores from 90 CRC patients and in 90 samples of adjacent normal mucosa by tissue microarray. The expression of P-S6 (S235/236) was upregulated in CRC, with the positive rate of P-S6 (S235/236) in CRC (63.3%) significantly higher than that in control tissues (36.7%, 30%) (p<0.05). P-S6 (S235/236) also correlated with high tumor histologic grade (p=0.002), and positive nodal metastasis (p=0.002). In contrast, the expression level of DEPTOR was correlated with low tumor histological grade (p=0.006), and negative nodal metastasis (p=0.001). Interestingly, P-S6 (S235/236) expression showed a significant negative association with the expression of DEPTOR in CRC (p=0.011, R= -0.279). However, upregulation of P-S6 (S235/236) (p=0.693) and downregulation of DEPTOR (p=0.331) in CRC were not significantly associated with overall survival. Thus, we conclude that expression of DEPTOR negatively correlates with mTORC1 activity and tumor progression in CRC. DEPTOR is a potential marker for prognostic evaluation and a target for the treatment of CRC.

[Protective effects of snake venom antimicrobial peptide OH-CATH on E. coli induced rabbit urinary tract infection models].

To investigate the potential protective effects of the snake venom antimicrobial peptide OH-CATH, we used a series of rabbit urinary tract infection models successfully induced by cephalosporin-resistant E.coli and E. coli ATCC 25922. The experimental models were administered saline, snake venom antimicrobial peptide OH-CATH, Cefoperazone and Sulbactam through the urethra. Urine was collected on days 1, 5, 10 and 14 after model establishment and urine culture was done to check the infection in each experimental animals. On day 14, all the animals were sacrificed and the bladder tissue specimens were taken for observation by H-E staining light microscope and transmission electron microscope. We found that the snake venom antimicrobial peptide OH-CATH reduced bacterial count in urine culture in both cephalosporin-resistant E. coli and the E. coli ATCC 25922 infected animals, while Cefoperazone and Sulbactam were only able to reduce the positive rate induced by the E. coli ATCC 25922 but had no obvious effects on animal model induced by cephalosporin-resistant E. coli strains (P<0.05). We also found less necrosis, degeneration and inflammatory cell infiltration in bladder tissue in OH-CATH groups as compared with the other experimental groups. The snake venom antimicrobial peptide OH-CATH had stable antibacterial activity against cephalosporin-resistant E. coli and E. coli ATCC 25922 and exhibited protective effects on both the cephalosporin-resistant E. coli and E. coli ATCC 25922 rabbit urinary tract infection models, suggesting that the molecule may have potential clinical applications in treating urinary tract infections.

Upregulation of tumor necrosis factor receptor-associated factor 6 correlated with synovitis severity in rheumatoid arthritis.

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic inflammatory disease leading to joint destruction and disability. Focal bone erosion is due to excess bone resorption of osteoclasts. Tumor necrosis factor receptor-associated factor 6 (TRAF6) is one of the critical mediators both in inflammatory signal pathway and differentiation and resorption activity of osteoclasts. Here we aimed to investigate TRAF6 expression in RA synovium and its correlation with histological synovitis severity and radiological joint destruction in RA. METHODS: Synovitis score was determined in needle biopsied synovium from 44 patients with active RA. Synovium from nine patients with osteoarthritis (OA) and seven with orthopedic arthropathies (Orth.A) were enrolled as "less inflamed" disease controls. Serial sections were stained immunohistochemically for TRAF6 as well as CD68 (macrophage), CD3 (T cell), CD20 (B cell), CD38 (plasmocyte), CD79a (B lineage cells from pre-B cell to plasmocyte stage), and CD34 (endothelial cell). Double immunofluorescence staining of TRAF6 and CD68 were tested. Densities of positive staining cells were determined and correlated with histological disease activity (synovitis score) and radiographic joint destruction (Sharp score). RESULTS: TRAF6 expression was found in the intimal and subintimal area of RA synovium, with intense staining found in the endochylema and nucleus of intimal synoviocytes and subintimal inflammatory cells. Double immunofluorescence staining showed TRAF6 was expressed in most of the intimal cells and obviously expressed in CD68+ cells and some other CD68- cells in subintimal area. Synovial TRAF6 was significantly over-expressed in the RA group compared with the OA and Orth.A group (2.53 ± 0.94 vs. 0.72 ± 0.44 and 0.71 ± 0.49, P < 0.0001). Synovial TRAF6 expression in RA correlated significantly with synovitis score (r = 0.412, P = 0.006), as well as the inflammatory cell infiltration (r = 0.367, P = 0.014). Significant correlation was detected between synovial TRAF6 expression and intimal CD68+ cells, as well as the cell density of subintimal CD68+ cells, CD3+ cells, CD20+ cells, CD38+ cells, and CD79a+ cells (all P < 0.05). CONCLUSIONS: Elevated synovial TRAF6 expression correlated with synovitis severity and CD68+ cell density in RA. It is, therefore, hypothesized that synovial TRAF6 is involved in the pathogenesis of synovial inflammation and osteoclast differentiation in RA.

Synovial infiltration with CD79a-positive B cells, but not other B cell lineage markers, correlates with joint destruction in rheumatoid arthritis.

OBJECTIVE: The efficacy of B cell depletion in the treatment of patients with rheumatoid arthritis (RA) has revitalized interest in the pathogenic role(s) of B cells in RA. We evaluated the distribution of synovial B lineage cells and their correlation with histologic disease activity and joint destruction in RA. METHODS: Synovial tissue samples were obtained by closed-needle biopsy from 69 Chinese patients with active RA, from 14 patients with osteoarthritis (OA), and from 15 with orthopedic arthropathies (OrthA) as disease controls. Serial tissue sections were stained immunohistochemically for CD79a (pro-B cell to plasma cell), CD20 (B cells), CD38 (plasma cells), CD21 (follicular dendritic cells), CD68 (macrophages), CD3 (T cells), and CD34 (endothelial cells). Densities of positive-staining cells were determined and correlated with histologic disease activity (Krenn 3-component synovitis score) and radiographic joint destruction (Sharp score). RESULTS: Mean sublining CD79a-positive cell density was significantly higher in RA than in OA (p <0.001) or OrthA (p = 0.003). Receiver operating characteristic curve analysis showed that CD79a-positive cell density differentiated RA well from OA [area under the curve (AUC) = 0.79] or OrthA (AUC = 0.75). Spearman's rank order correlation showed significant correlations between sublining CD79a-positive cell density and the synovitis score (r = 0.714, p < 0.001), total Sharp score (r = 0.490, p < 0.001), and the erosion subscore (r = 0.545, p < 0.001), as well as the joint space narrowing subscore (r = 0.468, p = 0.001) in RA. CONCLUSION: Synovial CD79a-positive B cells may be a helpful biomarker for histologic disease activity in RA and may be involved in the pathogenesis of joint destruction in RA.

Effective treatment of Kimura's disease with leflunomide in combination with glucocorticoids.

Kimura's disease (KD) is a rare, benign, chronic inflammatory disease which typically presents as persisting or recurring tumor-like lesions in the head and neck area that can be easily misdiagnosed. We report one patient with KD treated with leflunomide in combination with glucocorticoids and analyzed the literature on treatment of KD. The patient had a recurrent mass in the left upper arm with eosinophilia and elevated serum IgE but no renal involvement. The clinical manifestations improved markedly within 1 month, and blood eosinophil count and serum IgE normalized. Corticosteroids were then tapered gradually without recurrence or severe side effects in the 2-year follow-up period. Literature analysis identified four different non-drug interventions and 18 different drugs for treating KD, most of which were obtained from case reports. Our use of combination therapy of leflunomide and glucocorticoids suggests the need for a controlled trial for the treatment of this rare disorder.

Elevated serum glucose-6-phosphate isomerase correlates with histological disease activity and clinical improvement after initiation of therapy in patients with rheumatoid arthritis.

OBJECTIVE: To determine serum glucose-6-phosphate isomerase (GPI) concentrations in patients with rheumatoid arthritis (RA), and to test whether they correlate with objective measures of disease activity. METHODS: Sera from 116 patients with RA, 69 patients with non-RA rheumatic diseases, and 101 healthy controls were analyzed. Levels of soluble serum GPI were measured by ELISA. Histological disease activity was determined with the synovitis score in synovial needle biopsies from 58 of the 116 patients with RA. Thirty-one of the 58 synovium samples were stained for CD68, CD3, CD20, CD38, CD79a, and CD34 by immunohistochemistry. Demographic data were collected, as well as serological and clinical variables that indicate RA disease activity, for Spearman correlation analysis. RESULTS: Serum GPI level correlated positively with the synovitis score (r = 0.278, p = 0.034). Significantly higher soluble GPI levels were detected in the RA sera compared with sera from healthy controls and the non-RA disease controls (2.25 ± 2.82 vs 0.03 ± 0.05 and 0.19 ± 0.57 µg/ml, respectively; p < 0.0001). The rate of serum GPI positivity was significantly higher in the RA patients than in the non-RA disease controls (64.7% vs 10.1%; p < 0.0001). Spearman analysis showed no significant correlation between serum GPI level and Disease Activity Score in 28 joints at baseline. After initiation of antirheumatic treatments, GPI levels decreased significantly (2.81 ± 3.12 vs 1.44 ± 2.09 µg/ml; p = 0.016), paralleling improvement of the disease activity indices. CONCLUSION: Elevated serum GPI may be involved in the synovitis of RA and may prove useful as a serum marker for disease activity of RA.

Scavenging of Cd through Fe/Mn oxides within natural surface coatings.

The dynamics of Cd scavenging from solutions by Fe/Mn oxides in natural surface coatings (NSCs) was investigated under laboratory conditions. Selective extraction methods were employed to estimate the contributions of Fe/Mn oxides, where hydroxylamine hydrochloride (0.01 mol/L NH2OH x HCl + 0.01 mol/L HNO3), sodium dithionite (0.4 mol/L Na2S2O4) and nitric acid (10% HNO3) were used as extraction reagents. The Cd scavenging was accomplished with developing periods of the NSCs (totally 21 data sets). The resulting process dynamics fitted well to the Elovich equation, demonstrating that the amount of Cd scavenged was proportional to the increments of Fe/Mn oxides that were accumulated in the NSCs. The amount of Cd bound to Fe oxides (M,,) and Mn oxides (MCdMn could be quantified by solving two equations based on the properties of two extraction reagents. The amount of Cd scavenged by Fe/Mn oxides could also be estimated using MCdFe and MCdMn, divided by the total amounts of Fe and Mn oxides in the NSCs, respectively. The results indicated that the Cd scavenging by Fe/Mn oxides was dominated by Fe oxides, with less roles attributed to Mn oxides. The estimated levels of Cd scavenging through Fe and Mn oxides agreed well with those predicted through additive-adsorption and linear-regression models.

Effect of bio-surfactant on municipal solid waste composting process.

Bio-surfactant is a new type of surfactant that is produced in microbial metabolism. Adding bio-surfactant during composting process, especially to those contain some toxic substances, has been proved to be a promising way. In this study, Strains III (2), a bacterial with high activity to produce bio-surfactant, were isolated firstly. Following comparison experiments with and without adding Strains III (2), namely Run 1 and Run R, were conducted, respectively. The experimental results showed that, by adding Strains III (2), the surface tension could reduce from 46.5 mN/m to 39.8 mN/m and the corresponding time to maintain the surface tension under 50 mN/ m could prolong from 60 h to 90 h. The oxygen uptake rate and total accumulated oxygen consumption with Stains III (2) were both higher than those without Strains III (2), while the accumulation of H2S in outlet gas was reduced to around 50% of Run R. Moreover, two additional experiments were also carried out to examine the effects of strains coming from different systems. One is adding Strains III (2) with a dose of 0.4% (Run 2), and the other is seedling commercial Strains at the same conditions, the composting experiments showed that: Run 2 was more effective than Run 3, because the commercial Strains can be suppressed significantly in a complex composting system with different pH, high temperature and some of metals. The bio-surfactant was also added into the solid waste, which contained some toxic substances, the corresponding results showed that the remove rate of Hg and sodium pentachlorophenolate (PCP-Na) could be improved highly. Thus, the microenvironment, reactionrate and composting quality could be enhanced effectively by adding bio-surfactant to the composting process.