M6A methylation-regulated autophagy may be a new therapeutic target for intervertebral disc degeneration.

Degeneration of intervertebral discs is considered one of the most important causes of low back pain and disability. The intervertebral disc (IVD) is characterized by its susceptibility to various stressors that accelerate the senescence and apoptosis of nucleus pulposus cells, resulting in the loss of these cells and dysfunction of the intervertebral disc. Therefore, how to reduce the loss of nucleus pulposus cells under stress environment is the main problem in treating intervertebral disc degeneration. Autophagy is a kind of programmed cell death, which can provide energy by recycling substances in cells. It is considered to be an effective method to reduce the senescence and apoptosis of nucleus pulposus cells under stress. However, further research is needed on the mechanisms by which autophagy of nucleus pulposus cells is regulated under stress environments. M6A methylation, as the most extensive RNA modification in eukaryotic cells, participates in various cellular biological functions and is believed to be related to the regulation of autophagy under stress environments, may play a significant role in nucleus pulposus responding to stress. This article first summarizes the effects of various stressors on the death and autophagy of nucleus pulposus cells. Then, it summarizes the regulatory mechanism of m6A methylation on autophagy-related genes under stress and the role of these autophagy genes in nucleus pulposus cells. Finally, it proposes that the methylation modification of autophagy-related genes regulated by m6A may become a new treatment approach for intervertebral disc degeneration, providing new insights and ideas for the clinical treatment of intervertebral disc degeneration.

Associations of oxidative balance score with lumbar spine osteopenia in 20-40 years adults: NHANES 2011-2018.

PURPOSE: Current research suggests that oxidative stress may decrease bone mineral density (BMD) by disrupting bone metabolism balance. However, no study investigated the relationship between systemic oxidative stress status and adult BMD. This study aims to investigate whether oxidative balance score (OBS) is associated with BMD in adults under 40. METHODS: 3963 participants were selected from the National Health and Nutrition Survey (NHANES) from 2011 to 2018. OBS is scored based on 20 dietary and lifestyle factors. Weighted multiple logistic regression and restricted cubic splines were used to assess the correlation between OBS and osteopenia. RESULTS: After adjusting for confounding factors, the weighted logistic regression results showed that compared with the first tertile of OBS, the highest tertile had a 38% (OR: 0.62, 95% CI: 0.47-0.82) lower risk of osteopenia. The restrictive cubic spline curve indicates a significant nonlinear correlation between OBS and the risk of osteopenia. CONCLUSION: The research findings emphasize the relationship between OBS and the risk of osteopenia in young adults. Adopting an antioxidant diet and lifestyle may help young adults to maintain bone mass.

Tert-butyl hydroperoxide induces ferroptosis of bone mesenchymal stem cells by repressing the prominin2/BACH1/ROS axis.

Ferroptosis has been proven critical for survival following bone marrow mesenchymal stem cells (BMSCs) explantation. Suppression of ferroptosis in BMSCs will be a valid tactic to elevate the therapeutic potential of engrafted BMSCs. Prominin2 is a pentaspanin protein involved in mediating iron efflux and thus modulates resistance to ferroptosis, but its role in tert-butyl hydroperoxide (TBHP)-induced BMSCs ferroptosis remains elusive. We examined the biological effect of prominin2 in vitro and in vivo by using cell proliferation assay, iron assay, reactive oxygen species (ROS) examination, malondialdehyde assay, glutathione (GSH) examination, Western blot, quantitative reverse transcription-PCR, immunofluorescence staining assay, gene expression inhibition and activation, co-immunoprecipitation (CO-IP) assay, radiographic analysis, and histopathological analysis. Our study demonstrated that prominin2 activity was impaired in TBHP-induced BMSCs ferroptosis. We found that PROM2 (encoding the protein prominin2) activation delayed the onset of ferroptosis and PROM2 knockdown deteriorated the course of ferroptosis. CO-IP, Western blot, and immunofluorescence demonstrated that prominin2 exerts antiferroptosis effects by inhibiting BTB and CNC homology 1 (BACH1) that promotes ROS generation, and thus exerts potent antioxidant effects in oxidative stress (OS)-induced BMSCs ferroptosis, including elevating BMSCs' survival rate and enhancing GSH contents. BMSCs with PROM2 overexpression also partially delayed the progression of intervertebral disk degeneration in vivo, as illustrated by less loss of disk height and lower histological scores. Our findings revealed a mechanism that the prominin2/BACH1/ROS axis participates in BMSCs ferroptosis and the strengthening of this axis is promising to maintain BMSCs' survival after explantation.NEW & NOTEWORTHY We found that prominin2 might be a potential biomarker and is expected to be utilized to augment engrafted bone marrow mesenchymal stem cells (BMSCs) survival rate. The prominin2/BTB and CNC homology 1 (BACH1)/reactive oxygen species (ROS) axis, which participates in the regulation of BMSCs ferroptosis induced by tert-butyl hydroperoxide (TBHP), is uncovered in our study. The therapeutic targeting of the prominin2/BACH1/ROS axis components is promising to elevate the survival of transplanted BMSCs in clinical practice.

Thinopyrum intermedium TiAP1 interacts with a chitin deacetylase from Blumeria graminis f. sp. tritici and increases the resistance to Bgt in wheat.

The biotrophic fungal pathogen Blumeria graminis f. sp. tritici (Bgt) is a crucial factor causing reduction in global wheat production. Wild wheat relatives, for example Thinopyrum intermedium, is one of the wild-used parents in wheat disease-resistant breeding. From T. intermedium line, we identified the aspartic protease gene, TiAP1, which is involved in resistance against Bgt. TiAP1 is a secreted protein that accumulates in large amounts at the infection sites of Bgt and extends to the intercellular space. Yeast two-hybrid, luciferase complementation imaging and bimolecular florescent complimentary analysis showed that TiAP1 interacted with the chitin deacetylase (BgtCDA1) of Bgt. The yeast expression, purification and in vitro test confirmed the chitin deacetylase activity of BgtCDA1. The bombardment and VIGS-mediated host-induced gene silencing showed that BgtCDA1 promotes the invasion of Bgt. Transcriptome analysis showed the cell wall xylan metabolism, lignin biosynthesis-related and defence genes involved in the signal transduction were up-regulated in the transgenic TiAP1 wheat induced by Bgt. The TiAP1 in wheat may inactivate the deacetylation function of BgtCDA1, cause chitin oligomers expose to wheat chitin receptor, then trigger the wheat immune response to inhibit the growth and penetration of Bgt, and thereby enhance the resistance of wheat to pathogens.

Complications and outcomes of open posterior lumbar spinal fusion surgery in obese patients: a meta-analysis.

OBJECTIVE: The aim of this study was to determine whether obesity affects the operation, complications and outcomes after open posterior lumbar spinal fusion surgery for the treatment of low back pain and leg pain. METHODS: A meta-analysis of studies that compared the outcome of posterior lumbar spinal fusion in obese and non-obese patients. A total of 16 studies were included. RESULTS: There was no difference in pain and functional outcomes. Posterior lumbar spinal fusion in obese patients resulted in a statistically significant increase in intra-operative blood loss (weighted mean difference 40.93, 95% confidence interval (CI) 15.97-65.90, n = 243, and p=.001), longer duration of surgery (weighted mean difference -1.64, 95% CI -4.12 to 0.84, n = 1460, and p=.19), more complications (odds ratio: 1.59, 95% CI 1.24-2.05, n = 339, and p<.001) and extend length of stay (weighted mean difference 0.31, 95% CI 0.07-0.55, n = 1408, and p=.01). CONCLUSIONS: Obese patients experience more blood loss, longer duration of surgery, more complications and extended length of stay, but their back and leg pain and functional outcomes are similar to non-obese patients. Based on these results, obesity is not a contraindication to open posterior lumbar spinal fusion surgery.

Seed-specific expression of TaYUC10 significantly increases auxin and protein content in wheat seeds.

KEY MESSAGE: Present study revealed that specific expression of TaYUC10.3 in wheat young seeds could increase the content of auxin, and protein. Auxin is a vital endogenous hormone in plants, which is involved in the regulation of various physiological and biochemical processes in plants. The flavin-containing monooxygenase encoded by the YUCCA gene is a rate-limiting enzyme in the tryptophan-dependent pathway of auxin synthesis. TaYUC10.3 was identified, cloned and found that it was abundantly expressed in wheat young seeds. In this study, a seed-specific expression vector of TaYUC10.3 was constructed with the promoter of 1Bx17 glutenin subunit gene and transformed wheat using the particle bombardment method. The quantitative RT-PCR showed that TaYUC10.3 was expressed in a large amount in young seeds of the transgenic lines. Plant hormone-targeted metabolomics showed that the auxin content of the transgenic lines was significantly increased compared with controls. The GC / MS non-targeted metabolite multiple statistical analyses showed that the variable importance in projection (VIP) of tryptophan reduced in the transgenic lines. Simultaneously, the VIP of indole acetic acid increased. The precursor amino acids for synthesizing some proteins and carbohydrates were upregulated in the transgenic lines. Subsequently, it was found that the protein content of the seeds of the transgenic TaYUC10.3 wheat was significantly higher than that of the control. The wet gluten content and sedimentation value of the transgenic TaYUC10.3 wheat were also high. This result indicated that TaYUC10.3 might participate in auxin synthesis and affects the protein content of wheat seeds.

Prevalence and risk factor for refractive error in rural Chinese adults in Kailu, Inner Mongolia.

PURPOSE: To investigate the prevalence of refractive error in adults 40 years of age and older in Kailu, Inner Mongolia. METHODS: A population-based, cross-sectional study was conducted in Chinese adults. Spherical equivalent (S.E.) refractive error was determined from the right eye. Myopia and hyperopia were defined as a spherical equivalent (S.E.) < -0.5 dioptres (D) and >0.5 D, respectively. Since the prevalence of high myopia will vary with the precise criterion chosen, the prevalence of this condition was calculated for thresholds of both <-5.0 D and <6.0 D. Astigmatism was defined as cylinder power >0.5 D. Anisometropia was defined as a difference in S.E. between the two eyes >1.0 D. RESULTS: The prevalence of myopia, high myopia (<-5.0 D/<-6.0 D) and hyperopia in Kailu adults was 60.3% (95%CI: 58.95-61.71), 5.5% (95%CI: 4.82-6.10) /4.0% (95%CI: 3.47-4.57) and 12.2% (95%CI: 11.26-13.11), respectively. The age- and gender-standardised prevalence of myopia, high myopia (-5.0 D/-6.0 D) and hyperopia were 62.5% (95%CI: 61.05-63.99), 5.0% (95%CI: 4.34-5.61) /3.5% (95%CI: 2.99-4.04) and 10.6% (95%CI: 9.71-11.49), respectively. 52.9% had refractive astigmatism >0.5 D and 18.8% of subjects had clinically significant anisometropia. Age was significantly associated with hyperopia, high myopia, astigmatism and anisometropia. Myopia was more prevalent in females. Individuals with a higher educational level had a greater and lesser likelihood of myopia and astigmatism, respectively. CONCLUSIONS: Myopia affects around two-thirds of the rural Chinese population over 40 years of age in Kailu. This high prevalence highlights that rural populations should be included in epidemiological studies of refractive error. Further investigations are needed to clarify the role of environmental factors in myopia development.

Protein kinase RNA-like ER kinase/eukaryotic translation initiation factor 2α pathway attenuates tumor necrosis factor alpha-induced apoptosis in nucleus pulposus cells by activating autophagy.

Cellular loss induced by tumor necrosis factor alpha (TNF-α) contributes to the pathogenesis of intervertebral disc (IVD) degeneration. Cellular stress induced by TNF-α activates several processes to restore cell homeostasis. These processes include autophagy, endoplasmic reticulum stress, and related unfolded protein response (UPR). However, the effect and mechanism of UPR and autophagy regulated by TNF-α in IVD degeneration (IDD) remain unclear. The effect of autophagy on biological changes in nucleus pulposus cells (NPCs) also remains elusive. In this study, rat NPCs were cultured with TNF-α in the presence or absence of the UPR or autophagy pathway small-interfering RNAs. The associated genes and proteins were evaluated through immunofluorescence staining, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses to monitor UPR and autophagy signaling and identify the regulatory mechanism of autophagy by the UPR pathway. Trypan blue exclusion assay, cell flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, qRT-PCR, and western blot analyses were performed to examine the apoptosis of NPCs. The results showed that the acute exposure of TNF-α induced the apoptosis of rat NPCs and activated the protein kinase RNA-like ER kinase/eukaryotic translation initiation factor 2α (PERK/eIF2α) pathway of UPR and initiated autophagy. Silencing the PERK/eIF2α pathway or inhibiting autophagy enhanced the apoptosis of NPCs. Interference of the PERK/eIF2α pathway suppressed the autophagy of rat NPCs under TNF-α stimulation. Taken together, the PERK/eIF2α pathway reinforces the survival of NPCs under TNF-α stimulation by activating autophagy. Therefore, PERK/eIF2α-dependent autophagy could be a novel biological therapeutic target for IDD.

Quercetin Inhibits Cell Migration and Invasion in Human Osteosarcoma Cells.

BACKGROUND/AIMS: Osteosarcoma is a malignant tumor associated with high mortality; however, no effective therapies for the disease have been developed. Several studies have focused on elucidating the pathogenesis of osteosarcoma and have aimed to develop novel therapies for the disease. Quercetin is a vital dietary flavonoid that has been shown to have a variety of anticancer effects, as it induces cell cycle arrest, apoptosis, and differentiation and is involved in cell adhesion, metastasis and angiogenesis. Herein, we aimed to investigate the effects of quercetin on osteosarcoma migration and invasion in vitro and in vivo and to explore the molecular mechanisms underlying its effects on osteosarcoma migration and invasion. METHODS: Cell viability, cell cycle activity and cell apoptosis were measured using CCK-8 assay and flow cytometry, and cell migration and invasion were evaluated by wound healing and transwell assays, respectively. The mRNA and protein expression levels of several proteins of interest were assessed by real-time quantitative PCR and western blotting, respectively. Moreover, a nude mouse model of human osteosarcoma lung metastasis was established to assess the anti-metastatic effects of quercetin in vivo. RESULTS: We noted no significant differences in cell cycle activity and apoptosis between HOS and MG63 cells and control cells. Treatment with quercetin significantly attenuated cell migration and invasion in HOS and MG63 cells compared with treatment with control medium. Moreover HIF-1α, VEGF, MMP2, and MMP9 mRNA and protein expression levels were significantly downregulated in HOS cells treated with quercetin compared with HOS cells treated with controls. Additionally, treatment with quercetin attenuated metastatic lung tumor formation and growth in the nude mouse model of osteosarcoma compared with treatment with controls. CONCLUSION: Our findings regarding the inhibitory effects of quercetin on cell migration and invasion suggest that quercetin may have potential as a therapy for human osteosarcoma.

53BP1 promotes microhomology-mediated end-joining in G1-phase cells.

Alternative non-homologous end joining (alt-NHEJ) was originally identified as a backup repair mechanism in the absence of classical NHEJ (c-NHEJ) factors but recent studies have demonstrated that alt-NHEJ is active even when c-NHEJ as well as homologous recombination is available. The functions of 53BP1 in NHEJ processes are not well understood. Here, we report that 53BP1 promotes DNA double-strand break (DSB) repair and genomic stability not only in c-NHEJ-proficient but also -deficient human G1-phase cells. Using an array of repair substrates we show that these effects of 53BP1 are correlated with a promotion of microhomology-mediated end-joining (MMEJ), a subtype of alt-NHEJ, in G1-phase. Consistent with a specific role in MMEJ we confirm that 53BP1 status does not affect c-NHEJ. 53BP1 supports sequence deletion during MMEJ consistent with a putative role in facilitating end-resection. Interestingly, promotion of MMEJ by 53BP1 in G1-phase cells is only observed in the presence of functional BRCA1. Depletion of both 53BP1 and BRCA1 increases repair needing microhomology usage and augments loss of DNA sequence, suggesting that MMEJ is a highly regulated DSB repair process. Together, these findings significantly expand our understanding of the cell-cycle-dependent roles of 53BP1 in DSB repair.

Characteristics of Long-term Nonprogressors and Viremia Controllers Infected with HIV-1 via Contaminated Blood Donations or Transfusions Conducted 20 Years Earlier.

To characterize long-term nonprogressors (LTNPs) and viremia controllers (VCs), infected with HIV-1 through contaminated blood donation or transfusion between 1992 and 1996 in Henan, China. LTNPs and VCs were defined by CD4+T lymphocyte (CD4) count and viral load (VL). Of 29,294 patients infected with HIV-1 via contaminated blood donation or transfusion that had conducted for more than 20 years, 92 were LTNPs/VCs. There were 70 LTNPs (0.24%), 43 VCs (0.15%), and 48 LTNPs+VCs- (0.16%). VCs had a significantly lower CD4 nadir, compared to LTNPs and LTNPs+VCs-, and no significant differences for the highest VL and HIV-1 DNA. Cases P4 and P5 were LTNPs, while their VL reached approximately 4.3 log copies/mL. P6 was a VC, but with CD4 < 500 cells/µL constantly. Data from the LTNPs/VCs cohort provided valuable information, future research is needed.

Depth map sensor based on optical doped lens with multi-walled carbon nanotubes of liquid crystal.

In this paper, we present a novel design concept for determining the depth map of three-dimensional (3D) scenes based on an electrically controlled liquid crystal (LC) lens. The advantages of the proposed method are that it does not need any mechanical movements and a large amount of computations to acquire a depth map of a 3D scene in a relatively short amount of time. The tunable-focus LC lens doped with multi-walled carbon nanotubes is to become a key optical component for determining a depth map system. Sequenced two-dimensional images of slightly different perspectives are recorded in a short time, and the depth map of the 3D scene, according to a proposed depth estimation method and a focusing evaluation function, can be acquired in a simple way. This new method to acquire a depth map based on a doped LC lens maximizes the use of the proposed LC lens. The proposed system is novel in its compact, simple, and fast features, so we believe the proposed method can open a new creative dimension in image analysis and imaging systems and can also overcome the limitations of the conventional imaging mode.

Stereoselective Blockage of Quinidine and Quinine in the hERG Channel and the Effect of Their Rescue Potency on Drug-Induced hERG Trafficking Defect.

Diastereoisomers of quinidine and quinine are used to treat arrhythmia and malaria, respectively. It has been reported that both drugs block the hERG (human ether-a-go-go-related gene) potassium channel which is essential for myocardium repolarization. Abnormality of repolarization increases risk of arrhythmia. The aim of our research is to study and compare the impacts of quinidine and quinine on hERG. Results show that both drugs block the hERG channel, with quinine 14-fold less potent than quinidine. In addition, they presented distinct impacts on channel dynamics. The results imply their stereospecific block effect on the hERG channel. However, F656C-hERG reversed this stereoselectivity. The mutation decreases affinity of the two drugs with hERG, and quinine was more potent than quinidine in F656C-hERG blockage. These data suggest that F656 residue contributes to the stereoselective pocket for quinidine and quinine. Further study demonstrates that both drugs do not change hERG protein levels. In rescue experiments, we found that they exert no reverse effect on pentamidine- or desipramine-induced hERG trafficking defect, although quinidine has been reported to rescue trafficking-deficient pore mutation hERG G601S based on the interaction with F656. Our research demonstrated stereoselective effects of quinidine and quinine on the hERG channel, and this is the first study to explore their reversal potency on drug-induced hERG deficiency.

Efficacy of Foldable Capsular Vitreous Body Implants Filled With Light or Heavy Silicone Oil in the Treatment of Silicone Oil-dependent Eyes.

Purpose: The purpose of this study was to compare the clinical efficacy of foldable capsular vitreous body (FCVB) filled with either light or heavy silicone oil and the incidence of complications after their implantation for the treatment of severe ocular trauma and silicone oil-dependent eyes. Methods: FCVB filled with either light (n = 16) or heavy (n = 8) silicone oil was implanted in 24 patients. During the 12-month follow-up period, the intraocular pressure, final best-corrected visual acuity, retinal reattachment condition, position of the FCVB, and complications were assessed. Results: All surgeries were performed without issue. There was no significant difference in preoperative and postoperative best-corrected visual acuity between the two groups. A significant improvement in the intraocular pressure was observed after surgery in both the light silicone oil (P = 0.029) and heavy silicone oil (P = 0.035) groups. None of the patients developed displacement or prolapse of the FCVB. The most common early and late postoperative complications were postoperative hemorrhage (33.3%) and corneal opacification (50%), respectively. Conclusions: FCVB filled with heavy silicone oil can be used as a supplemental therapy for patients who have lost the anterior segment of their eye, have lesions of the inferior retina, or cannot maintain the prone position for various reasons. Translational Relevance: Implantation of FCVB combined with heavy silicone oil compensates for the shortcomings of this with light silicone oil, providing patients with more personalized treatment.

Polyphenols as Potential Antioxidants for the Treatment of Intervertebral Disc Degeneration.

Intervertebral disc degeneration (IDD) is a common musculoskeletal system disease, which is one of the most important causes of low back pain. Despite the high prevalence of IDD, current treatments are limited to relieving symptoms, and there are no effective therapeutic agents that can block or reverse the progression of IDD. Oxidative stress, the result of an imbalance between the production of reactive oxygen species (ROS) and clearance by the antioxidant defense system, plays an important role in the progression of IDD. Polyphenols are antioxidant compounds that can inhibit ROS production, which can scavenge free radicals, reduce hydrogen peroxide production, and inhibit lipid oxidation in nucleus pulposus (NP) cells and IDD animal models. In this review, we discussed the antioxidant effects of polyphenols and their regulatory role in different molecular pathways associated with the pathogenesis of IDD, as well as the limitations and future prospects of polyphenols as a potential treatment of IDD.

Single-Cell Transcriptome Landscape and Cell Fate Decoding in Human Brain Organoids after Transplantation.

Human stem cells and derivatives transplantation are widely used to treat nervous system diseases, while the fate determination of transplanted cells is not well elucidated. To explore cell fate changes of human brain organoids before and after transplantation, human brain organoids are transplanted into prefrontal cortex (PFC) and hippocampus (HIP), respectively. Single-cell sequencing is then performed. According to time-series sample comparison, transplanted cells mainly undergo neural development at 2 months post-transplantation (MPT) and then glial development at 4MPT, respectively. A different brain region sample comparison shows that organoids grafted to PFC have obtained cell fate close to those of host cells in PFC, other than HIP, which may be regulated by the abundant expression of dopamine (DA) and acetylcholine (Ach) in PFC. Meanwhile, morphological complexity of human astrocyte grafts is greater in PFC than in HIP. DA and Ach both activate the calcium activity and increase morphological complexity of astrocytes in vitro. This study demonstrates that human brain organoids receive host niche factor regulation after transplantation, resulting in the alignment of grafted cell fate with implanted brain regions, which may contribute to a better understanding of cell transplantation and regenerative medicine.

Repeat Surgery after Percutaneous Endoscopic Lumbar Discectomy for Adolescent Lumbar Disc Herniation: A Multicenter Observational Study.

OBJECTIVE: The reported date in the repeat surgical intervention for adolescent lumbar disc herniation (ALDH) after percutaneous endoscopic lumbar discectomy (PELD) was quite scarce. This study aims to introduce cases of repeat surgeries after PELD for ALDH and assess the incidence, chief causes, repeat surgery methods, and surgical outcomes of repeat surgeries after PELD for ALDH. METHODS: A retrospective multicenter observational study was conducted on patients undergoing repeat surgeries after PELD for ALDH at four tertiary referral hospitals from January 2014 through August 2022. The incidence of repeat surgeries, chief causes, strategies for repeat surgeries, and timing of repeat surgeries were recorded and analyzed. The clinical outcomes were evaluated by the Numeric Rating Scales (NRS) scores and the modified MacNab criteria. Statistical analyses were performed with the Wilcoxon signed-rank test. RESULTS: A total of 23 patients who underwent repeat surgeries after PELD for ALDH were included. The chief causes were re-herniation (homo-lateral re-herniation at the same level, new disc herniation of adjacent level). The repeat surgery methods were revision PELD, micro-endoscopic discectomy (MED), open discectomy and instrumented lumbar inter-body fusion. The NRS scores decreased significantly in follow-up evaluations and these scores demonstrated significant improvement at the last follow-up (p < 0.002). For the modified MacNab criteria, at the last follow-up, 18 patients (78.26%) had an excellent outcome, and the overall success rate was 86.95%. CONCLUSION: This study's data suggest that young patients who underwent repeat surgery improved significantly compared to baseline. The chief cause was re-herniation. Revision PELD was the main surgical procedure, which provides satisfactory clinical results in young patients who underwent repeat surgeries.

Apoptosis induced by trimethyltin chloride in human neuroblastoma cells SY5Y is regulated by a balance and cross-talk between NF-κB and MAPKs signaling pathways.

Trimethyltin chloride (TMT) has been known as a classic neurotoxicant which can cause serious neuronal degeneration diseases. Nuclear factor κB (NF-κB) and mitogen-activated protein kinases (MAPKs) signaling pathways play pivotal role in the central nerves system. In the present study, the intracellular pathways involved in TMT-induced apoptosis on human neuroblastoma cells SY5Y (SH-SY5Y) were investigated. We observed high level of nuclear NF-κB p65 submit, activated JNK, ERK, and p38 by TMT exposure. In contrast, low level of Bcl-2 and XIAP (two known NF-κB-regulated endogenous anti-apoptotic molecules) was present. To further investigate the role of these pathways and the relationship between them, specific inhibitors were used and the alteration of each pathway was evaluated. Pretreatment with MG132, an inhibitor of proteasome activity, and BAY11-7082, an inhibitor of IκBα phosphorylation, both inhibited NF-κB p65 translocation and significantly promoted apoptosis. NF-κB inhibition also induced down-expression of Bcl-2 and XIAP, exaggerated JNK phosphorylation, and ERK inhibition. SP600125 and U0126, by blocking the phosphorylation of c-Jun and MEK1/2, inhibited JNK and ERK phosphorylation, respectively, and attenuated apoptosis significantly. JNK and ERK inhibition also induced IκBα degradation and NF-κB p65 translocation, leading to expression of Bcl-2 and XIAP. The detrimental role of MG132 and BAY11-7082 appears related to the exaggerated JNK phosphorylation. The SP600125 and U0126 neuroprotection appears related to NF-κB-regulated transcriptional control of Bcl-2 and XIAP. These results suggest that the cross-talk and a balance between NF-κB and MAPKs may be involved in TMT-induced apoptosis on SH-SY5Y cells.

[Epidemiological survey on the hepatitis C virus and its genotyping analysis in Henan province in 2012].

OBJECTIVE: To investigate the prevalence and distribution of hepatitis C virus (HCV) genotypes in Henan province in 2012. METHODS: A total of 32 203 permanent residents (1 to 74 years old) in Henan were recruited using multi-stage random samping method from March to June 2012. All participants were asked to complete a questionnaire to collect demographic information, past medical history and the exposure history of risk factors. A blood sample of 5 ml was collected at the same time. The condition of anti-HCV and HCV RNA was determined through the ELISA test and nested RT-PCR. HCV RNA positive samples were further subject to the nonstructural protein 5 region (NS5B) gene amplification and sequencing. The sequence was amplified for the phylogenetic tree and genetic analysis. The differences of the positive rate of anti-HCV and HCV RNA and the HCV genetic subtype distribution in different respondents'characteristics were analyzed. RESULTS: Among 32 203 subjects, the overall positive rate of anti-HCV and HCV RNA were 0.48% (153/32 203) and 0.24% (78/32 203), in which men were 0.42% (65/15 634), and 0.23% (36/15 634), and women were 0.53% (88/16 569) and 0.25% (42/16 596). The differences between men and women were not statistically significant (χ(2) values were 2.26, 0.18, respectively, both P values > 0.05). The results of NS5B genotyping and molecular evolution analysis showed that there were six subtypes in the 71 HCV RNA positive samples.In those six subtypes, the proportion of genotypes 1b, 6a, 3a, 2a, 3b and 1a were 56.3% (40/71), 19.7% (14/71), 11.3% (8/71), 8.5% (6/71), 2.8% (2/71) and 1.4% (1/71), respectively. The HCV genetic subtypes of infestor were mainly present with two branches of 1b and 6a, and the two subtypes Bootstrap values were 0.95. CONCLUSION: The prevalence of HCV infection was high in Henan. The major HCV genotypes in patients with HCV infection were 1b and 6a.

[Down-regulation of Smoothened gene expression inhibits proliferation of breast cancer stem cells].

OBJECTIVE: To investigate the influence of down-regulating Smoothened (SMO) gene expression through short hairpin RNA (shRNA) on the proliferation of breast cancer stem cells. METHODS: Human SMO shRNA was designed, synthesized chemically, and transfected into MCF-7 cells to down-regulate SMO gene. By using G418, stable cells with down-regulated SMO were selected. In vitro proliferation of these cells was measured by CCK8 assay. The proportion of CD44(+)/CD24(-) cells was detected by flow cytometry and the mammospheres formation was determined by suspension sphere culture. The expression of SMO, GLI1 and Oct4 was detected by Western blot. In vivo, the volume of tumor was measured every 3 days and the expression of SMO, GLI1 and Oct4 detected by Western blot. RESULTS: In vitro, the cells were transfected with SMO-shRNA and selected by G418 after 21 days. SMO-shRNA effectively down-regulated the expression of SMO gene and protein, and inhibited the proliferation of MCF-7 and markedly reduced the proportion of CD44(+)/CD24(-) cells and mammospheres. In vivo, SMO-shRNA treatment of MCF-7 significantly inhibited the volume of tumor. The positive rate of SMO in negative control and SMO-shRNA group was 5/5 and 2/5, respectively. The expression of SMO, GLI1 and Oct4 in different groups were 0.72 ± 0.17 and 0.21 ± 0.09, 1.21 ± 0.21 and 0.47 ± 0.12, 0.83 ± 0.13 and 0.25 ± 0.07. SMO, GLI1 and Oct4 down-regulation significantly suppressed at protein levels (P < 0.05). CONCLUSION: The shRNA by chemical synthesis can effectively down-regulate SMO gene expression and inhibit the proliferation of breast cancer stem cells.