MicroRNA-30b promotes axon outgrowth of retinal ganglion cells by inhibiting Semaphorin3A expression

Semaphorin3A (Sema3A) is a major inhibitory factor of optic nerve (ON) regeneration post-injury. Many microRNAs (miRNAs) are expressed specifically in the mammalian brain and retina and are dynamically regulated during development, suggesting that this group of miRNAs may be associated with neural development. We found that microRNA-30b (miR-30b) bound to the three prime untranslated region (3' UTR) of Sema3A and inhibited the expression of Sema3A mRNA. The mRNA expression level of miR-30b and the protein expression levels of Sema3A, Neuropilin1 (NRP1), PlexinA1 (PlexA1), phosphorylated p38MAPK (p-p38MAPK), and active caspase-3 were all upregulated in retinas from rats with a damaged ON relative to those with an intact ON. Transfection of cultured retinal ganglion cells (RGCs) with an miR-30b mimic led to decreased levels of Sema3A, NRP1, PlexA1, p-p38MAPK, and active caspase-3 protein expression, as well as axon elongation and reduced levels of apoptosis. These findings provide evidence that miR-30b inhibits Sema3A expression. Decreased Sema3A expression promotes axon outgrowth in RGCs due to reduced levels of Sema3A binding to NRP1 and PlexA1 and simultaneously reduces apoptosis by inhibiting the p38MAPK and caspase-3 pathways. Our findings provide the first evidence that miR-30b-mediated Sema3A downregulation may serve as a new strategy for the clinical treatment of ON injury.

Clinical applications of internal heat source analysis for breast cancer identification

Nondestructive preoperative breast imaging techniques are widely used for breast cancer testing and diagnosis. This study aimed to evaluate the feasibility and efficacy of quantitative diagnosis via the thermal analysis of abnormal metabolism. Nine hundred forty-eight women who underwent breast biopsy from 2009 to 2013 were investigated. Thermal analysis was used to calculate the internal heat source (i.e., tumor) thermal power for each participant. The applicability and effectiveness of our approach were estimated using the chi-square test, kappa statistics (k), and odds ratios (OR). Breast density and tumor size were considered during this estimation. A thermal power q = 0.2 w was determined as the optimal separation threshold between breast cancer and benign disease. Moreover, good agreement (k = 0.837) with the gold-standard assessment (breast biopsy) was confirmed in 93.2% of the patients (N = 884/948), and the sensitivity and specificity were 94.2 and 92.9%, respectively. The results also found no significant differences in methodological accuracy between the fatty and dense breasts (OR = 1.194, P = 0.524). Furthermore, after dividing the cohort into three groups according to tumor size (T1: <2 cm; T2: 2 to 5 cm; T3: >5 cm), the tumor size had no effect on the proposed method (ORs = 1, P = 0.724). Internal heat source analysis can feasibly and efficiently distinguish between breast cancer and benign disease.

Neurofilament M gene in a French-Canadian Population with Parkinson’s Disease

Background:

Recently, a single base pair substitution (G1747A) mutation of the neurofilament M (NF-M) gene was reported in a French-Canadian patient with early onset Parkinson’s disease (PD). Three unaffected siblings were found to be heterozygotes for the NF-M Gly336Ser mutation but, to date, no other affected PD individuals have been found with a similar mutation. No other individuals with Parkinson’s disease and of similar ethnic background have been screened for this mutation.

Methods:

We screened 102 French-Canadian patients with definite PD and 45 French-Canadian controls for this substitution in the NF-M gene using a PCR-restriction enzyme digestion method.

Results:

None of the patients or controls carried this mutation.

Conclusion:

Our results would indicate that this mutation is not common even in a PD population of similar ethnic background and suggest this change represents a rare variant. However, these results do not exclude the possibility that other mutations in this gene could be present.

Histone phosphorylation: its role during cell cycle and centromere identity in plants

As the main protein components of chromatin, histones can alter the structural/functional capabilities of chromatin by undergoing extensive post-translational modifications (PTMs) such as phosphorylation, methylation, acetylation, ubiquitination, sumoylation, and so on. These PTMs are thought to transmit signals from the chromatin to the cell machinery to regulate various processes. Histone phosphorylation is associated with chromosome condensation/segregation, activation of transcription, and DNA damage repair. In this review, we focus on how different histone phosphorylations mark for chromatin change during the cell cycle, the relationship between histone phosphorylation and functional centromeres, and the candidate kinases that trigger and the phosphatase or kinase inhibitors that alter histone phosphorylation. Finally, we review the crosstalk between different PTMs.

The delayed massive hemorrhage after gastrectomy in patients with gastric cancer: characteristics, management opinions and risk factors

AIMS

This study was designed to investigate the clinical features of delayed massive hemorrhage (DMH) after gastrectomy in patients with gastric cancer (GC).

METHODS

This study retrospectively reviewed 1536 GC patients with major gastrectomy between 1998 and 2011. Based on the time onset of postoperative bleeding, patients were divided into early postoperative hemorrhage (EPH), delayed massive hemorrhage (DMH), and no-bleeding groups. Postoperative mortality, bleeding treatment, and risk factors of hemorrhage were explored.

RESULTS

In sum, 15 (0.9%) patients suffered from DMH, with three (20%) dead cases. None of 18 (1.2%) patients with EPH died, but there were three dead cases in no-bleeding group. DMH had more extra-intestinal bleeding (P = 0.037) than EPH. Angiographic embolization was performed in 12 (80%) of DMH patients and successful in ten cases. Surgical procedures were applied in only two embolization-failed cases. Extended lymphadenectomy (P = 0.038), vascular skeletonization (P = 0.012) and advanced TNM stage (P < 0.001) were correlated with DMH.

CONCLUSIONS

DMH can be successfully managed with angiographic embolization, followed by alternative surgery. Extensive lymphadenectomy and vascular skeletonization should be discreetly performed during gastrectomy.

Anti-phosphorylated histone H2AThr120: a universal microscopic marker for centromeric chromatin of mono- and holocentric plant species

Based on the analysis of 20 different monocot and eudicot species, we propose that the centromeric distribution of the phosphorylated histone H2AThr120 is evolutionary highly conserved across species with mono- and holocentric chromosomes. Therefore, antibodies recognizing the phosphorylated threonine 120 of the histone H2A can serve as a universal marker for the cytological detection of centromeres of mono- and holokinetic plant species. In addition, super resolution microscopy of signals specific to the centromere-specific histone H3 variant CENH3 and to H2AThr120ph revealed that these histone variants are incorporated into different nucleosomes, which form distinct, partly intermingled chromatin domains. This specific arrangement of both histone variants suggests different centromeric functions during the cell cycle.

Induced immune tolerance of autoantigen loaded immature dendritic cells in homogenic lupus mice

This study investigated the induced immune tolerance of autoantigen dendritic cells (imDCs) in homogenic lupus mice to support the use of dendritic cell treatment against autoimmune diseases, such as systemic lupus erythematosus. A lupus mouse was used to model based on in vitro cell culture. An immunohistochemistry assay was used to assess CD8(+), CD4(+) cell ratio in mouse spleen cells. The ratio of CD4(+)CD25(+) cells in mouse spleen lymphocytes was detected by flow cytometry, whereas the kidney was directly measured by immunofluorescence. After the injection of mouse antigen loaded bone marrow-derived antigen imDCs with a homogenetic background, mouse nucleoprotein immune with a homogenetic background was carried out. The results were compared against the simple mouse nucleoprotein immune model with a homogenic background. The 24-h urine protein, serum antinuclear antibody and anti-ds-DNA antibodies of the simple mouse model were lower compared to group S1. The CD4(+)CD25(+) cell percentage of spleen was higher in the simple mouse model compared to group S1. In the spleen, the number of lymphocyte CD8(+) cells declined, whereas the number of CD4(+) cells increased. In conclusion, after autoantigen uptake, imDCs are able to induce immune tolerance to the antigen by reinfusion, which appears to prevent or mitigate systemic lupus erythematosus-like illness.

Woven silk fabric-reinforced silk nanofibrous scaffolds for regenerating load-bearing soft tissues

Although three-dimensional (3-D) porous regenerated silk scaffolds with outstanding biocompatibility, biodegradability and low inflammatory reactions have promising application in different tissue regeneration, the mechanical properties of regenerated scaffolds, especially suture retention strength, must be further improved to satisfy the requirements of clinical applications. This study presents woven silk fabric-reinforced silk nanofibrous scaffolds aimed at dermal tissue engineering. To improve the mechanical properties, silk scaffolds prepared by lyophilization were reinforced with degummed woven silk fabrics. The ultimate tensile strength, elongation at break and suture retention strength of the scaffolds were significantly improved, providing suitable mechanical properties strong enough for clinical applications. The stiffness and degradation behaviors were then further regulated by different after-treatment processes, making the scaffolds more suitable for dermal tissue regeneration. The in vitro cell culture results indicated that these scaffolds maintained their excellent biocompatibility after being reinforced with woven silk fabrics. Without sacrifice of porous structure and biocompatibility, the fabric-reinforced scaffolds with better mechanical properties could facilitate future clinical applications of silk as matrices in skin repair.

SRPK1 Dissimilarly Impacts on the Growth, Metastasis, Chemosensitivity and Angiogenesis of Glioma in Normoxic and Hypoxic Conditions

Glioma is among the ten most common causes of cancer-related death and has no effective treatment for it, so we are trying to find a new target for anticancer treatment. This study investigates the different expression of SRPK1 as a novel protein in glioma, which can influence tumor cells biological characteristics in normoxic and hypoxic environment. The expression levels of SRPK1 protein in glioma cell lines transfected with siSRPK1 or not were examined using immunofluorescence, RT-PCR and Western blot analysis, respectively. The impact of SRPK1 on the biological characteristics of U251 cells was further studied using methylthiazol tetrazolium assays, flow cytometry, and Transwell invasion chamber assays. The results showed that knockdown of SRPK1 inhibited tumor cells growth, invasion and migration in normoxic condition, but portion of the effect could be reversed in hypoxia. SRPK1 expression was induced in glioma cells by DDP treated, but not TMZ, in both normoxia and hypoxia conditions. We propose SRPK1 as a new molecular player contributing to the early treatment of glioma.

LHX6 acts as a novel potential tumour suppressor with epigenetic inactivation in lung cancer

LIM homeobox domain 6 (LHX6) is a putative transcriptional regulator that controls the differentiation and development of neural and lymphoid cells. However, the function of LHX6 in cancer development remains largely unclear. Recently, we found that LHX6 is hypermethylated in lung cancer. In this study, we analysed its epigenetic regulation, biological functions, and related molecular mechanisms in lung cancer. Methylation status was evaluated by methylation-specific PCR and bisulfite genomic sequencing. LHX6 mRNA levels were measured in relation to the methylation status. The effects of LHX6 expression on tumourigenesis were studied in vitro and in vivo. LHX6 was readily expressed in normal lung tissues without methylation, but was downregulated or silenced in lung cancer cell lines and tissues with hypermethylation status. Treatment of lung cancer cells with the demethylating agent 5-aza-2′-deoxycytidine restored LHX6 expression. Moreover, LHX6 hypermethylation was detected in 56% (52/93) of primary lung cancers compared with none (0/20) of the tested normal lung tissues. In lung cancer cell lines 95D and H358, forced expression of LHX6 suppressed cell viability, colony formation, and migration, induced apoptosis and G1/S arrest, and inhibited their tumorigenicity in nude mice. On the other hand, knockdown of LHX6 expression by RNA interference increased cell proliferation and inhibited apoptosis and cell cycle arrest. These effects were associated with upregulation of p21 and p53, and downregulation of Bcl-2, cyclinD1, c-myc, CD44, and MMP7. In conclusion, our results suggest that LHX6 is a putative tumour suppressor gene with epigenetic silencing in lung cancer.

Changes in gut microbial populations, intestinal morphology, expression of tight junction proteins, and cytokine production between two pig breeds after challenge with Escherichia coli K88: a comparative study

This study hypothesized that the gut microbial populations, intestinal morphology, and cytokine production are differentially altered in 2 different pig breeds, namely, Chinese native Jinhua pigs and European Landrace pigs, after orally challenge with enterotoxigenic Escherichia coli (ETEC) K88. A total of 12 Jinhua pigs and 12 Landrace pigs were allocated to either the nonchallenged or the challenged groups (6 pigs per group). The challenged pigs were orally administered ETEC K88, and their nonchallenged counterparts were given sterile Luria-Bertani broth. Selected gut microbial populations, intestinal morphology, mRNA expression of tight junction proteins, and the levels of ileal cytokines and secretory immunoglobulin A (sIgA) production were measured in Jinhua and Landrace pigs. The results showed that the challenged Jinhua pigs exhibited a significantly (P < 0.05) lower incidence of diarrhea compared with their Landrace counterparts. The Escherichia coli (E.coli) population and the percentage of E. coli in the total bacteria population were increased in response to ETEC K88 challenge in both Jinhua and Landrace pigs. The challenged Landrace pigs shed more E. coli (P < 0.05) and had higher percentage of E. coli in the total bacteria population in the colon (P < 0.05) compared with their Jinhua counterparts. Both pig breeds tended to exhibit greater villous atrophy and crypt depth reduction in all of the intestinal segments with challenge. The expression of tight junction proteins decreased in response to ETEC K88 challenge in both pig breeds. The levels of the proinflammatory cytokines interferon (IFN)-γ, tumor necrosis factor-α, and IL-6 and the secretion of sIgA were positively altered whereas the levels of the anti-inflammatory cytokine IL-4 and transforming growth factor (TGF)-β were negatively altered by ETEC K88 challenge in both breeds. Jinhua pigs exhibited significantly higher levels of IFN-γ and TGF-β (P < 0.05) in the challenged group. Our findings provide valuable evidence to explain the differences in the intestinal physiology between Jinhua and Landrace pigs; that is, Jinhua pigs appeared to show better growth performance, a lower incidence of diarrhea, and a lower extent of immune activation in response to ETEC K88 challenge and a higher Lactobacillus population, a higher percentage of Lactobacillus in the total bacteria population, a higher ratio of Lactobacillus to E. coli, and higher levels of tight junction proteins with and without challenge.

Arsenic trioxide induced apoptosis in retinoblastoma cells by abnormal expression of microRNA-376a

Arsenic trioxide (ATO) has been demonstrated to induce apoptosis in retinoblastoma cells, however, mechanisms responsible for this phenomenon are not fully understood. In the present study, we determined whether ATO induced apoptosis by abnormal expression of microRNA. In an apoptosis model of retinoblastoma cells subjected to 4 μM ATO for 72 hours, we found 14 miRNAs changed more than 2-fold by using miRNA microarray analysis. Most of these aberrantly expressed miRNAs were confirmed by quantitative RT-PCR. MiR-376a, a significantly down-regulated miRNA, was selected for further study. The overexpression of miR-376a resulting from miR-376a mimic transfection significantly inhibited ATO-induced apoptosis. By contrast, miR-376a deficiency resulting from miR-376a inhibitor transfection aggravated ATO-induced apoptosis. Using bioinformatic algorithms, caspase-3, a key apoptosis executioner, was predicted as a putative target of miR-376a. The quantitative RT-PCR showed no effects of miR-376a mimic or inhibitor on caspase-3 mRNA level. However, the amount of caspase-3 proteins was reduced by miR-376a mimic, whereas increased by miR-376a inhibitor. Furthermore, the luciferase reporter assay confirmed caspase-3 to be a target of miR-376a, and the apoptosis caused by miR-376a inhibitor were abolished by a caspase-3 inhibitor. These results suggest that ATO -induced apoptosis in retinoblastoma cells is part mediated by decreasing expression of miR-376a, which subsequently increased caspase-3 expression.