Genomic gain/methylation modification/hsa-miR-132-3p increases RRS1 overexpression in liver hepatocellular carcinoma.

This study aimed to determine the upstream regulatory factors affecting ribosome biogenesis regulator 1 homolog (RRS1) expression and the development and prognosis of liver hepatocellular carcinoma (LIHC). The expression profiles of RRS1 were evaluated in pan-cancer tissues and liver tumor cell lines. The associations of RRS1 with pan-cancer survival, immune infiltrations, immune checkpoints, and drug sensitivity were identified. We explored the potential upstream regulatory mechanisms of RRS1 expression. Hsa-miR-132-3p knockdown, CCK-8 assays, transwell, and wound healing assays were performed to validate the regulatory effect of hsa-miR-132-3p on RRS1 expression and the development of LIHC. Our findings demonstrated that RRS1 was significantly elevated in 27 types of cancers. RRS1 predicts a poor outcome of LIHC, lung adenocarcinoma, head and neck cancer, and kidney papillary cell carcinoma. RRS1 expression showed a significant association with immune cell infiltrates and the expression of immune checkpoints-related genes in LIHC tissues. Increased RRS1 expression may have a negative effect on these anticancer drugs of LIHC. Low methylation of the RRS1 promoter and its genomic gain may elevate RRS1 expression and predict poor prognosis for LIHC. Increased hsa-miR-132-3p expression may elevate RRS1 expression and result in poor prognosis for LIHC. Hsa-miR-132-3p inhibition can decrease RRS1 expression and the development of liver tumor cell lines. Low methylation of the RRS1 promoter, RRS1 genomic gain, and hsa-miR-132-3p upregulation in LIHC may promote RRS1 upregulation and thus lead to the development and poor prognosis for LIHC. RRS1 is a promising therapeutic target for LIHC.

PARK7 enhances antioxidative-stress processes of BMSCs via the ERK1/2 pathway.

Oxidative stresss in the microenvironment surrounding lesions induces apoptosis of transplanted bone-marrow-derived mesenchymal stem cells (BMSCs). Hence, there is an urgent need for improving antioxidative-stress processes of transplanted BMSCs to further promote their survival. The present study reports the role and mechanism of Parkinson's disease protein 7 (PARK7) in enhancing antioxidative activity in BMSCs. We used a PARK7 lentivirus to transfect BMSCs to up- or downregulate PARK7, and then used H2 O2 to simulate oxidative stress in BMSCs in vitro. Overexpression of PARK7 effectively reduced reactive oxygen species and malondialdehyde, protected mitochondrial membrane potential, and resisted oxidative-stress-induced apoptosis of BMSCs, but the expression of PARK7 was downregulated, these results were reversed. At the same time, we also found that overexpression of PARK7 increased extracellular-regulated protein kinase 1/2 (ERK1/2) phosphorylation and nuclear translocation, as well as upregulated Elk1 phosphorylation and superoxide dismutase (SOD) expression. In contrast, when U0126 was used to block the ERK1/2 pathway, ERK1/2 and Elk1 phosphorylation levels were downregulated, ERK1/2 nuclear translocation and SOD content were significantly reduced, and PARK7-overexperssion-induced antioxidative activity was completely blocked. Collectively, our results suggest that PARK7 overexpression increased antioxidative-stress processes and survival of BMSCs subjected to H2 O2 via activating the ERK1/2 signaling pathway. Our findings may guide the development of a PARK7-specific strategy for improving the transplantation efficacy of BMSCs.

New strategy of bone marrow mesenchymal stem cells against oxidative stress injury via Nrf2 pathway: oxidative stress preconditioning.

Clinically, bone marrow mesenchymal stem cells (BMSCs) have been used in treatment of many diseases, but the local oxidative stress (OS) of lesion severely limits the survival of BMSCs, which reduces the efficacy of BMSCs transplantation. Therefore, enhancing the anti-OS stress ability of BMSCs is a key breakthrough point. Preconditioning is a common protective mechanism for cells or body. Here, the aim of this study was to investigate the effects of OS preconditioning on the anti-OS ability of BMSCs and its mechanism. Fortunately, OS preconditioning can increase the expression of superoxide dismutase, catalase, NQO1, and heme oxygenase 1 through the nuclear factor erythroid 2-related factor 2 pathway, thereby decreased the intracellular reactive oxygen species (ROS) levels, relieved the damage of ROS to mitochondria, DNA and cell membrane, enhanced the anti-OS ability of BMSCs, and promoted the survival of BMSCs under OS.

[Oxidative stress preconditioning alleviates oxidative stress-induced damage of bone marrow mesenchymal stem cells].

Objective To investigate the effect of oxidative stress preconditioning on the oxidative stress-induced damage of bone marrow mesenchymal stem cells (BMSCs). Methods BMSCs were isolated and cultured by density gradient centrifugation combined with adherence method. The cells were divided into three groups: control group (control medium), oxidative damage group (treated with 1000 µmol/L H2O2 for 24 hours), and preconditioning group (preincubated with 50 µmol/L H2O2 for 8 hours before treatment with 1000 µmol/L H2O2 for 24 hours). DCFH-DA staining was used to analyze the level of reactive oxygen species (ROS). Mitochondrial membrane potential was measured by JC-1 staining. DNA damage was detected by TUNEL. Malondialdehyde (MDA) content was detected by thiobarbituric acid (TBA) method, and superoxide dismutase (SOD) activity was detected by water soluble tetrazolium-1 (WST-1) assay. CCK-8 assay was used to detect cell viability and flow cytometry to detect cell apoptosis. Results Compared with the oxidative damage group, the preconditioning group had reduced ROS level, reduced DNA damage, higher mitochondrial membrane potential, significantly decreased MDA content, increased SOD activity, increased cell viability, and significantly decreased apoptosis. Conclusion Oxidative stress preconditioning can enhance the anti-oxidative stress ability of BMSCs and promote its survival under oxidative stress.

[Effects of nicotinamide mononucleotide adenylyl transferase 3 on mitochondrial function and anti-oxidative stress of rabbit bone marrow mesenchymal stem cells via regulating nicotinamide adenine dinucleotide levels].

OBJECTIVE: To investigate the effect of nicotinamide mononucleotide adenosyl transferase 3 (NMNAT3) on the mitochondrial function and anti-oxidative stress of rabbit bone marrow mesenchymal stem cells (BMSCs) under oxidative stress in vitro by regulating nicotinamide adenine dinucleotide (NAD +) levels. METHODS: The bone marrow of femur and tibia of New Zealand white rabbits were extracted. BMSCs were isolated and cultured in vitro by density gradient centrifugation combined with adherent culture. The third generation cells were identified by flow cytometry and multi-directional induction. Overexpression of NMNAT3 gene was transfected into rabbit BMSCs by enhanced green fluorescent protein (EGFP) labeled lentivirus (BMSCs/Lv-NMNAT3-EGFP), and then the expression of NMNAT3 was detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot and cell proliferation by cell counting kit 8 (CCK-8) method. BMSCs transfected with negative lentivirus (BMSCs/Lv-EGFP) and untransfected BMSCs were used as controls. The oxidative stress injury cell model was established by using H 2O 2 to treat rabbit BMSCs. According to the experimental treatment conditions, they were divided into 4 groups: Group A was normal BMSCs without H 2O 2 treatment; untransfected BMSCs, BMSCs/Lv-EGFP, and BMSCs/Lv-NMNAT3-EGFP in groups B, C, and D were treated with H 2O 2 simulated oxidative stress, respectively. The effects of NMNAT3 on the mitochondrial function of BMSCs under oxidative stress [changes of mitochondrial membrane potential, NAD + and adenosine triphosphate (ATP) levels], the changes of anti-oxidative stress ability of BMSCs [reactive oxygen species (ROS) and malondialdehyde (MDA) levels, manganese superoxide dismutase (Mn-SOD) and catalase (CAT) activities], and the effects of BMSCs on senescence and apoptosis [senescence associated-ß-galactosidase (SA-ß-gal) staining and TUNEL staining] were detected after 24 hours of treatment. RESULTS: The rabbit BMSCs were successfully isolated and cultured in vitro. The stable strain of rabbit BMSCs with high expression of NMNAT3 gene was successfully obtained by lentiviral transfection, and the expressions of NMNAT3 gene and protein significantly increased ( P<0.05). There was no significant difference in the trend of cell proliferation compared with normal BMSCs. After treatment with H 2O 2, the function of mitochondria was damaged and apoptosis increased in all groups. However, compared with groups B and C, the group D showed that the mitochondrial function of BMSCs improved, the membrane potential increased, the level of NAD + and ATP synthesis of mitochondria increased; the anti-oxidative stress ability of BMSCs enhanced, the levels of ROS and MDA decreased, and the activities of antioxidant enzymes (Mn-SOD, CAT) increased; and the proportion of SA-ß-gal positive cells and the rate of apoptosis decreased. The differences in all indicators between group D and groups B and C were significant ( P<0.05). CONCLUSION: NMNAT3 can effectively improve the mitochondrial function of rabbit BMSCs via increasing the NAD + levels, and enhance its anti-oxidative stress and improve the survival of BMSCs under oxidative stress conditions.

Preincubation with a low-dose hydrogen peroxide enhances anti-oxidative stress ability of BMSCs.

OBJECTIVE: To investigate the effects of low-concentration hydrogen peroxide pretreatment on the anti-oxidative stress of the bone marrow mesenchymal stem cells (BMSCs). METHODS: Rabbit BMSCs were isolated and cultured by density gradient centrifugation combined with the adherence method. Then, the third generation of well-grown BMSCs was continuously treated with 50-µM hydrogen peroxide (H2O2) for 8 h as the optimal pretreatment concentration and the BMSCs were continuously applied for 24 h with 500 µM H2O2, and the optimal damage concentration was determined as the oxidative stress cell model. The experiment was divided into three groups: control group, high-concentration H2O2 injury group (500 µM), and low-concentration H2O2 pretreatment group (50 µM + 500 µM). In each group, the DCFH-DA fluorescence probe was used to detect the reactive oxygen species (ROS). ELISA was used to detect the activity of superoxide dismutase (SOD) and catalase (CAT), and the TBA method was used to detect malondialdehyde (MDA). The mitochondrial membrane potential was detected by JC-1. The cell viability was detected by CCK-8 method, while flow cytometry and TUNEL/DAPI double staining were performed to detect cell apoptosis. Hence, the effect of H2O2 pretreatment on the anti-oxidative stress of BMSCs was investigated. One-way analysis of variance was performed using SPSS 19.0 statistical software, and P < 0.05 was considered statistically significant. RESULTS: A large number of typical BMSCs were obtained by density gradient centrifugation and adherent culture. The oxidative stress cell model was successfully established by 500-µM H2O2. Compared with the high-concentration H2O2 injury group, the low-concentration H2O2 pretreatment reduced the production of ROS [(62.33 ± 5.05), P < 0.05], SOD and CAT activities significantly increased (P < 0.05), and MDA levels significantly decreased (P < 0.05). The mitochondrial membrane potential fluorescence changes, the ratio of red/green fluorescence intensity of the high-concentration H2O2 injury group was less, and the ratio of the low-concentration H2O2 pretreatment group was significantly higher than that. The ratio of red/green increased by about 1.8 times (P < 0.05). The cell viability and survival rate of BMSCs were significantly increased in low-concentration H2O2 pretreatment group (P < 0.05), and the cell apoptosis rate was significantly decreased (P < 0.05). CONCLUSION: Pretreatment with low-concentration H2O2 can enhance the anti-oxidative stress ability and reduce their apoptosis of BMSCs under oxidative stress.

A novel fiber optical device for ultraviolet disinfection of water.

Since there are several problems in traditional UV disinfection techniques, a highly efficient, reliable and economical method, using quartz optical fibers to deliver UV light is proposed. The principle of the experimental setup is that ultraviolet rays are gathered by a reflector and converge on a light point, the diameter of approximately 5mm. In this way UV light can be transferred into water to kill the bacteria in the water. This paper presents preliminary results on water disinfection using this new UV disinfection setup. Its suitability for application could be shown in experiments with E. coli (ATCC8099) as test microorganisms. We have optimized the distribution of the optical fibers in the water in bench-scale study. This result can provide guidance for pilot-scale and field-scale study of this new technique. The results show that the new technique had a good performance under different conditions as follows: (a) turbidity level=10.2 NTU, (b) ferric ion concentration=0.3 mg/L, and (c) humic acid concentration=5 mg/L. The new technique provides a promising approach to disinfection treatment of drinking water.

Vertebral tumors: surgical versus nonsurgical treatment.

UNLABELLED: The treatment of spinal tumors represents a challenge to spine care professionals. Fortunately, the incidence of new cases of primary malignant bone tumors is lower compared with that of other tumors. In the United States approximately 2000 malignant bone tumors of 7000 new sarcomas are diagnosed each year. Of these, 4% to 20% (80-400 tumors) of bone tumors are spinal tumors. Metastatic tumors are the most frequent tumor of bone and the most frequent tumor of the spinal column regardless of the origin of the primary tumor. More than 90% of spinal tumors are metastatic. Thirty to seventy percent of patients who die from cancer have evidence of vertebral metastases visible on careful postmortem examination, with the potential that this number could reach 85% in patients with breast cancer. Less than 10% of patients with spinal tumors present with spinal instability requiring surgical treatment; this accounts for approximately 18,000 new cases yearly. We will focus on the most recent advances in nonsurgical and surgical treatment of vertebral tumors. In surgical treatment, the evaluation and selection of patients, indications and surgical strategies, open and minimally invasive techniques, outcomes and complications will be discussed. LEVEL OF EVIDENCE: Level V (expert opinion). See the Guidelines for Authors for a complete description of the levels of evidence.

Thirty-six years experience of cervical extension osteotomy in ankylosing spondylitis: techniques and outcomes.

STUDY DESIGN: A retrospective review of the cervical extension osteotomy in the past 36 years for the treatment of flexion deformity of patients with ankylosing spondylitis was conducted. OBJECTIVES: To review the conventional and current surgical techniques of cervical extension osteotomy in ankylosing spondylitis and to evaluate the clinical outcomes. SUMMARY OF BACKGROUND DATA: Cervical osteotomy is a challenging procedure in the correction of flexion deformity in ankylosing spondylitis. Some authors prefer using general anesthesia and prone position for their surgery, and some, including the authors, use the sitting position. METHODS: A review of 131 cases of cervical spine osteotomy was carried out. The accumulation of 131 cases was classified into two phases: 114 cases from 1967 to 1997 (conventional technique group) by our senior author and 17 cases from 1997 to 2003 (current technique group) by our first author. Patient follow-up was obtained by a combination of retrospective chart review and telephone interview by 2 independent physicians. The flexion deformity was measured before surgery and after surgery using chin-brow to vertical angle. RESULTS: There were 114 patients in the conventional group and 17 patients in the current group. The average preoperative and postoperative angle was 56 degrees and 4 degrees , respectively, in the conventional group and 49 degrees and 12 degrees , respectively, in the current group. CONCLUSIONS: The sitting position with local anesthesia is safe and allows for correction of deformity in a controlled manner. The increased lateral resection area reduces the possibility of nerve root impingement and provides ample room for the spinal cord. The cranial halo can also be adjusted after surgery to modify the head/neck position and can be adjusted to alleviate any C8 nerve root impingement. The procedure demands great attention to detail to minimize risk.

Value of magnetic resonance imaging and discography in determining the level of cervical discectomy and fusion.

STUDY DESIGN: The correlation between magnetic resonance imaging and discography of the cervical spine in degenerative disc disease was studied. In addition, the results of cervical discectomy and fusion were evaluated. OBJECTIVES: To compare the value of cervical magnetic resonance imaging versus discography in selecting the level for discectomy and fusion and to evaluate the surgical outcome. SUMMARY OF BACKGROUND DATA: The value of magnetic resonance imaging and discography in patients with cervical discogenic pain is less clear. Also, the status of a hypointense signal (dark) cervical disc and/or a small herniated disc on magnetic resonance imaging has not been determined. METHODS: The magnetic resonance imaging studies and discography followed by computed tomography in 55 patients with cervical discogenic pain were evaluated. Surgical planning was based on the complete information of clinical symptoms, magnetic resonance imaging, and discography as well as computed tomography discography. Anterior cervical discectomy and keystone fusion was performed. Postoperative pain relief was assessed by the patients, and the follow-up radiographs were viewed by an independent reviewer. The overall surgical outcome was evaluated using Odom's criteria. RESULTS: There were 161 disc levels that successfully underwent cervical discography with 79 positive levels. A positive discography result was found in 63% of dark (hypointense signal) discs and 45% of speckled discs. Fifty-nine percent of small herniated discs and 59% of torn discs had a positive discography, respectively. There were 100 abnormal cervical discs on magnetic resonance imaging. Magnetic resonance imaging had a false-positive rate of 51% and a false-negative rate of 27%. Successful cervical fusion was achieved in 95% of patients, and the overall satisfactory result was 76%. CONCLUSIONS: Magnetic resonance imaging can identify most of the painful discs but still has relatively high false-negative and false-positive rates. There is a high chance that hypointense signal and small herniated discs are the pain generators, but they are not always symptomatic. Discography can save the levels from being unnecessarily fused. The combination of clinical symptoms, magnetic resonance imaging, and discography provides the most information for decision making and can improve the management of cervical discogenic pain.