Effects of targeted muscle reinnervation on spinal cord motor neurons in rats following tibial nerve transection.

Targeted muscle reinnervation (TMR) is a surgical procedure used to transfer residual peripheral nerves from amputated limbs to targeted muscles, which allows the target muscles to become sources of motor control information for function reconstruction. However, the effect of TMR on injured motor neurons is still unclear. In this study, we aimed to explore the effect of hind limb TMR surgery on injured motor neurons in the spinal cord of rats after tibial nerve transection. We found that the reduction in hind limb motor function and atrophy in mice caused by tibial nerve transection improved after TMR. TMR enhanced nerve regeneration by increasing the number of axons and myelin sheath thickness in the tibial nerve, increasing the number of anterior horn motor neurons, and increasing the number of choline acetyltransferase-positive cells and immunofluorescence intensity of synaptophysin in rat spinal cord. Our findings suggest that TMR may enable the reconnection of residual nerve fibers to target muscles, thus restoring hind limb motor function on the injured side.

Comparative Proteomic Analysis of Posterior Silk Glands of Wild and Domesticated Silkworms Reveals Functional Evolution during Domestication.

The wild silkworm Bombyx mandarina was domesticated to produce silk in China approximately 5000 years ago. Silk production is greatly improved in the domesticated silkworm B. mori, but the molecular basis of the functional evolution of silk gland remains elusive. We performed shotgun proteomics with label-free quantification analysis and identified 1012 and 822 proteins from the posterior silk glands (PSGs) of wild silkworms on the third and fifth days of the fifth instar, respectively, with 128 of these differentially expressed. Bioinformatics analysis revealed that, with the development of the PSG, the up-regulated proteins were mainly involved in the ribosome pathway, similar to what we previously reported for B. mori. Additionally, we screened 50 proteins with differential expression between wild and domesticated silkworms that might be involved in domestication at the two stages. Interestingly, the up-regulated proteins in domesticated compared to wild silkworms were enriched in the ribosome pathway, which is closely related to cell size and translation capacity. Together, these results suggest that functional evolution of the PSG during domestication was driven by reinforcing the advantageous pathways to increase the synthesis efficiency of silk proteins in each cell and thereby improve silk yield.

Predictive and prognostic roles of ribonucleotide reductase M1 in patients with pancreatic cancer treated with gemcitabine: a meta-analysis.

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.

Proteome analysis of silkworm, Bombyx mori, larval gonads: characterization of proteins involved in sexual dimorphism and gametogenesis.

Sexual dimorphism is initialed by the components of the sex determination pathway and is most evident in gonads and germ cells. Although striking dimorphic expressions have been detected at the transcriptional level between the silkworm larval testis and the ovary, the sex-dimorphic expressions at the protein level have not yet been well characterized. The proteome of silkworm larval gonads was investigated using a shotgun-based identification. A total of 286 and 205 nonredundant proteins were identified from the silkworm testis and ovary, respectively, with a false discovery rate (FDR) lower than 1%. Only 40 and 16 proteins were previously identified, and 246 and 189 proteins were newly identified in the silkworm testis and the ovary, respectively. The gametogenesis mechanism of silkworm was demonstrated using the protein expression profile and bioinformatics analysis. Cellular retinoic acid binding protein (CRABP) showed to be highly abundant in testis, while tubulins were abundant in ovary. Several homologies of Drosophila essential proteins for gametogenesis were identified in silkworm, such as male meiotic arrest gene product ALY and VISMAY in testis, and maternal mRNA localization protein exuperantia and SQUID in ovary. The gene ontology (GO) annotation and pathway analysis provide system-level insights into the sexual dimorphism and gametogenesis.

Overexpression of mitogen-activated protein kinase kinase 4 and nuclear factor-kappaB in laryngeal squamous cell carcinoma: a potential indicator for poor prognosis.

This study aimed to investigate the expression and clinical significance of mitogen-activated protein kinase kinase 4 MKK4 and nuclear factor-kappaB (NF-kappaB) in patients with laryngeal squamous cell carcinoma (LSCC). We used immunohistochemistry (IHC) to examine the expression of MKK4 and NF-kappaB in 78 LSCCs and their adjacent normal tissues. To clarify the validity of MKK4 and NF-kappaB as determined by the IHC analysis, RT-PCR was performed on 21 tissues randomly selected from the 78 LSCCs. The positive expression rates of MKK4 and NF-kappaB in patients with LSCC were 67.9% (53/78) and 60.3% (47/78) respectively, which were significantly higher than those in the adjacent normal tissue (both P<0.01). The positive expression of MKK4 and NF-kappaB tended to be associated positively with lymph node metastasis (both P<0.01) as well as T stage (both P<0.01). The Spearman analysis indicated that the expression level of MKK4 was positively correlated with that of NF-kappaB significantly (rs=0.368, P<0.01). Overall survival curves estimated by Kaplan-Meier showed that tumor patients with low MKK4 and NF-kappaB expression in their tumor cells survive significantly longer than patients with high MKK4 and NF-kappaB levels (P=0.027, and P<0.01, respectively). In addition, multivariate Cox regression analysis showed that N stage, T stage and NF-kappaB expression are significant independent prognostic factors for overall survival (P<0.01, P=0.014, and P=0.027, respectively). These findings suggested that the expression of MKK4 and NF-kappaB may be considered as a useful prognostic marker of LSCC after surgical resection.

[Adenoviral-mediated APE/Ref-1 expression protects rat spiral ganglion cells from oxidative damage].

OBJECTIVE: To address the question if apurinic/apyrimidinic endonuclease/redox factor 1 (APE/Ref-1) involved in preventing spiral ganglion cells oxidative damage after oxidative stress. METHODS: Primary cultured rat spiral ganglion cells were infected with the adenovirus containing APE/Ref-1 for 48 h, then treated with H2O2 (0, 10, 25, 50, 100, 300 micromol/L) for 1 h, and finally changed back into normal medium. Western blot were used to detect the level of APE/Ref-1 protein in the infected cells to ensure APE/Ref-1 over expression as a result of adenovirus infection. The cell viability was determined by MTT and the apoptosis of spiral ganglion cells was determined by terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL). RESULTS: Western blot showed that infection of adenovirus resulted in APE/Ref-1 over expression in the spiral ganglion cells. Over expression of APE/Ref-1 significantly improved cell viability in cultures treated with different concentration H2O2 from 50 to 300 micromol/L However, the apoptosis of cells was significantly inhibited. CONCLUSIONS: Over expression of APE/Ref-1 could protect spiral ganglion cells from oxidative damage.