A multidimensional nomogram combining clinical factors and imaging features to predict 1-year recurrence of low back pain with or without radicular pain after spinal manipulation/mobilization.

BACKGROUND: In this retrospective study, we aimed to develop a nomogram to predict recurrence during a 1-year period of spinal manipulation/mobilization (SM/M) in patients with low back pain (LBP) with greater pain intensity, more severe comorbid conditions, or a neuropathic component. METHODS: A total of 786 consecutive patients with LBP treated with SM/M as primary therapy were divided into training (n = 545) and validation (n = 241) sets. Cox regression analyses were used to assess the relative value of clinical factors and lumbar magnetic resonance imaging features associated with recurrence during the 1-year period. Predictors of recurrence with significant differences were used to construct a nomogram in the training set. We evaluated the performance of the model on the training and validation sets to determine its discriminative ability, calibration, and clinical utility. The prognostic value of the nomogram for predicting recurrence was assessed using Kaplan-Meier analysis and time-dependent receiver operating characteristic analyses. RESULTS: A nomogram comprising hospitalization time, previous history of LBP, disease duration, lumbar range of motion, lower extremity tendon reflex, muscle strength, ratio of herniation to uncompressed dural sac area, and Pfirrmann classification was established for recurrence during a 1-year period after SM/M in patients with LBP. Favorable calibration and discrimination were observed in the nomogram training and validation sets (C-index 0.753 and 0.779, respectively). Decision curve analysis confirmed the clinical utility of the nomogram. Over a 1-year period, the nomogram showed satisfactory performance in predicting recurrence in LBP after SM/M. CONCLUSION: We established and validated a novel nomogram that can accurately predict a patient's risk of LBP recurrence following SM/M. This realistic prognostic model may aid doctors and therapists in their decision-making process and strategy optimization for non-surgical treatment of LBP using SM/M.

Stellar initial mass function varies with metallicity and time.

Most structural and evolutionary properties of galaxies strongly rely on the stellar initial mass function (IMF), namely the distribution of the stellar mass formed in each episode of star formation1-4. The IMF shapes the stellar population in all stellar systems, and so has become one of the most fundamental concepts of modern astronomy. Both constant and variable IMFs across different environments have been claimed despite a large number of theoretical5-7 and observational efforts8-15. However, the measurement of the IMF in Galactic stellar populations has been limited by the relatively small number of photometrically observed stars, leading to high uncertainties12-16. Here we report a star-counting result based on approximately 93,000 spectroscopically observed M-dwarf stars, an order of magnitude more than previous studies, in the 100-300 parsec solar neighbourhood. We find unambiguous evidence of a variable IMF that depends on both metallicity and stellar age. Specifically, the stellar population formed at early times contains fewer low-mass stars compared with the canonical IMF, independent of stellar metallicities. In more recent times, however, the proportion of low-mass stars increases with stellar metallicity. The variable abundance of low-mass stars in our Milky Way establishes a powerful benchmark for models of star formation and can heavily affect results in Galactic chemical-enrichment modelling, mass estimation of galaxies and planet-formation efficiency.

Ruxolitinib reduces severe CRS response by suspending CAR-T cell function instead of damaging CAR-T cells.

The therapeutic effect of CAR-T is often accompanied by sCRS, which is the main obstacle to the promotion of CAR-T therapy. The JAK1/2 inhibitor ruxolitinib has recently been confirmed as clinically effective in maintaining control over sCRS, however, its mechanism remains unclear. In this study, we firstly revealed that ruxolitinib significantly inhibited the proliferation of CAR-T cells without damaging viability, and induced an efficacy-favored differentiation phenotype. Second, ruxolitinib reduced the level of cytokine release not only from CAR-T cells, but also from other cells in the immune system. Third, the cytolytic activity of CAR-T cells was restored once the ruxolitinib was removed; however, the cytokines released from the CAR-T cells maintained an inhibited state to some degree. Finally, ruxolitinib significantly reduced the proliferation rate of CAR-T cells in vivo without affecting the therapeutic efficacy after withdrawal at the appropriate dose. We demonstrated pre-clinically that ruxolitinib interferes with both CAR-T cells and the other immune cells that play an important role in triggering sCRS reactions. This work provides useful and important scientific data for clinicians on the question of whether ruxolitinib has an effect on CAR-T cell function loss causing CAR-T treatment failure when applied in the treatment of sCRS, the answer to which is of great clinical significance.

Single-cell RNA sequencing reveals abnormal fluctuations in human eight-cell embryos associated with blastocyst formation failure.

Infertility has become a global health issue, with the number of people suffering from the disease increasing year by year, and ART offering great promise for infertility treatment. However, the regulation of early embryonic development is complicated and a series of processes takes place, including the maternal-to-zygotic transition. In addition, developmental arrest is frequently observed during human early embryonic development. In this study, we performed single-cell RNA sequencing on a biopsied blastomere from human eight-cell embryos and tracked the developmental potential of the remaining cells. To compare the sequencing results between different eight-cell embryos, we have combined the research data of this project with the data previously shared in the database and found that cells from the same embryo showed a higher correlation. Additionally, the transcriptome of embryos with blastocyst formation failure was significantly different from developed embryos, and the gene expression as well as cell signaling pathways related to embryonic development were also altered. In particular, the expression of some maternal and zygotic genes in the failed blastocyst formation group was significantly altered: the overall expression level of maternal genes was significantly higher in the failed blastocyst than the developed blastocyst group. In general, these findings provide clues for the causes of human embryonic arrest after the eight-cell stage, and they also provide new ideas for improving the success rate of ART in clinical practice.

SNHG16 lncRNAs are overexpressed and may be oncogenic in human gastric cancer by regulating cell cycle progression.

The small nucleolar RNA host gene 16 (SNHG16) has recently been shown to be a putative oncogene in gastric cancer (GC) and other cancer types, but how its four lncRNA variants are expressed in any physiological and pathological situation remains unknown. To investigate the expression and function of the four lncRNA variants of SNHG16, mainly the variant 1, in GC, we performed quantitative PCR to determine the RNA levels of the four variants in 60 GC tissue samples and several cell lines. We also studied how knocking down of SNHG16 with siRNA affected proliferation, apoptosis, cell cycle progression, as well as migration and invasion of GC cells. Our results showed that variants 1 and 4 were overexpressed in GC tissues compared with adjacent uninvolved tissues. Knockdown of the four variants, mainly the variant 1, enhanced apoptosis and inhibited cell cycle progression of a GC cell line by arresting the cells at the G1 phase. These cellular effects were associated not only with decreased protein levels of c-Myc, PCNA, cyclins D1, E1, A2 and B, as well as CDKs 2 and 6, but also with increased protein levels of the p21, p27 and p53. Knockdown of total SNHG16 lncRNAs also inhibited invasion and migration of the GC cells in vitro. These results collectively suggest that SNHG16 may be oncogenic in GC by regulating cell cycle progression and may serve as a GC biomarker.

[Staged surgery of Sanders type â £ calcaneal fractures with soft tissue three-degree swelling].

OBJECTIVE: To compare the clinical efficacy of staged surgery on Sanders Ⅳ calcaneal fractures with soft tissue Ⅲ swelling. METHODS: The clinical data of 76 patients with Sanders type Ⅳ closed calcaneal fracture with soft tissue three-degree swelling treated from June 2017 to May 2020 was retrospectively analyzed, including 54 males and 22 females, aged from 25 to 50 (38.16±10.24) years. The patients were divided into observation group and control group according to different treatment methods. Twenty-four patients in the observation group were treated by staged surgery stageⅠclosed prying traction reduction and Kirschner wire fixation, stageⅡopen reduction and internal fixation with titanium plate, including 17 males and 7 females, aged from 25 to 50 (36.12±9.56) years. There were 52 patients in the control group, including 37 males and 15 females, aged from 25 to 50 (38.32±10.67) years, these patients were treated with open reduction and internal fixation with titanium plate after the dermatoglyphic signs appeared. The swelling subsidence time, the length of hospitalization days, and the incidence of postoperative incision complications were compared between two groups. The Bhler angle, Gissane angle, and calcaneal varus angle were measured by X-ray before and 6 months after operation. American Orthopedic Foot and Ankle Society (AOFAS) about the ankle hindfoot score was used to evaluate the clinical efficacy. RESULTS: All 76 patients were followed up for 8 to 12 (9.52±2.01) months. The swelling subsidence time and hospitalization days in observation group were (12.12± 3.24) d and (24.53±6.44) d, respectively, which in control group were (15.16±4.16) d and (29.46±9.61) d, with statistical difference between two groups (P<0.05). Postoperative 6 months, Bhler angle, Gissane angle and calcaneal varus angle were (31.33±10.15)°, (145.34±8.04) ° and (10.31±3.23) ° in observation group, while those in control group were (20.24±8.23) °, (165.28±10.29) °and (21.24±5.27) °, with statistical difference between two groups (P<0.05). And there was significant difference in all patients between before and 6 months after operation (P<0.05). The AOFAS score of the observation group and control group were 71.76±9.84 and 57.23±10.76 at 6 months after operation, with significant different between two groups (P< 0.05). The excellent rate of observation group was significantly higher than that of control group (P<0.05). CONCLUSION: Compared with open reduction and internal fixation with titanium plate after the appearance of dermatoglyphic signs, staged surgery for Sanders type Ⅳ calcaneal fractures with soft tissue three-swelling does not increase the risk of soft tissue complications, and can significantly shorten the patient's swelling subsidence time and hospitalization days, improve the quality of fracture reduction and short term function, and relieve pain.

[Alternative Splicing Analysis of LACTB Gene and Expression Characteristics of Different Transcripts in Leukemia Cell Lines].

OBJECTIVE: To detect the expression of different transcripts of lactamase ß（LACTB) gene in leukemic cell lines. METHODS: NCBI website and DNAstar software were used to detect the Bioinformatics analysis of LACTB. The expression of different transcripts of LACTB gene in leukemic cell lines (THP-1, HL60, K562, U937, Jurkat and Raji) was detected by reverse transcription PCR (RT-PCR), DNA and clone sequencing; the expression of different transcripts of LACTB gene in leukemic cell lines was detected by Quantitative Real-time PCR. RESULTS: There were a variety of splicing isomers in LACTB, and it could produce a variety of protein isomers with conserved N-terminal and different C-terminal, moreover, there were many splice isoforms of LACTB in leukemia cell lines, and there were different expression patterns in different cell lines, including XR1, V1, V2 and V3. The expression of total LACTB showed high in HL60 cells, while low in Raji cells, and the difference was statistically significant (P<0.05). The V1 was high expression in U937 cells but low in Raji cells, and the difference was statistically significant (P<0.05). V2 was high expression in HL60 cells but lowly in Raji cells, and the difference was statistically significant (P<0.05). The expression of V3 was low in THP-1 cells, which was significantly different as compared with that in normal bone marrow (P<0.05). CONCLUSION: The reaserch found that there are many splice isomers of LACTB in leukemic cell lines, and there are different expression patterns in different cell lines.

Phytotoxic mechanism of allelochemical liquiritin on root growth of lettuce seedlings.

As the main active ingredient of the traditional Chinese medicine Glycyrrhiza uralensis Fisch, liquiritin has multiple biological activities, including anti-inflammatory, antihepatotoxicity, immune regulation, anti-virus and anti-cancer. In addition, liquiritin has been recognized as an allelochemical that displays markedly inhibitory effects on the growth of target plants, G. uralensis and lettuce. However, its phytotoxic mechanism remains unknown. In the present study, the mode of action of liquiritin against root growth of lettuce seedling was researched. After treatments with liquiritin, the cell division in root tips of lettuce seedlings was partly arrested, and the cell viability and root vitality were obviously lost. At the same time, overproduction of reactive oxygen species (ROS), malondialdehyde (MDA) and proline (Pro) in lettuce seedlings were induced by liquiritin. The results indicated that the phytotoxic effects of liquiritin was probably dependent on the induction of ROS overproduction, resulting in membrane lipids peroxidation following with cell death and mitosis process disorder.

Single-cell DNA methylation sequencing reveals epigenetic alterations in mouse oocytes superovulated with different dosages of gonadotropins.

BACKGROUND: Epigenetic abnormalities caused by superovulation have recently attracted increasing attention. Superovulation with exogenous hormones may prevent oocytes from establishing an appropriate epigenetic state, and this effect may extend to the methylation programming in preimplantation embryos, as de novo DNA methylation is a function of developmental stage of follicles and oocyte size. Follicle-stimulating hormone (FSH) and human menopausal gonadotropin (hMG) are common gonadotropins used for superovulation, and appropriate concentrations of these gonadotropins might be necessary. However, no systematic study on the effects of DNA methylation alterations in oocytes associated with superovulation with different dosages of FSH/hMG at the single-cell level has yet been reported. In the current study, different dosages of FSH/hMG combined with human chorionic gonadotropin (hCG) were used in female mice to generate experimental groups, while naturally matured oocytes and oocytes superovulated with only hCG were respectively used as controls. Single-cell level DNA methylation sequencing was carried out on all these matured oocytes. RESULTS: In this study, we revealed that the genome-wide methylation pattern and CG methylation level of the maternal imprinting control regions of all mature oocytes were globally conserved and stable. However, methylation alterations associated with superovulation were found at a specific set of loci, and the differentially methylated regions (DMRs) mainly occurred in regions other than promoters. Furthermore, some of the annotated genes in the DMRs were involved in biological processes such as glucose metabolism, nervous system development, cell cycle, cell proliferation, and embryo implantation and were altered in all dosages of FSH/hMG group (for example, Gfod2 and SYF2). Other genes were impaired only after high gonadotropin dosages (for instance, Sox17 and Phactr4). CONCLUSIONS: In conclusion, the current study addressed the effects of superovulation on DNA methylation from the perspective of different dosages of gonadotropins at the single-cell level. We found that the genome-wide DNA methylation landscape was globally preserved irrespective of superovulation or of the kind and dosage of gonadotropins used, whereas the methylation alterations associated with superovulation occurred at a specific set of loci. These observed effects reflect that superovulation recruits oocytes that would not normally be ovulated or that have not undergone complete epigenetic maturation. Our results provide an important reference for the safety assessment of superovulation with different dosages of gonadotropins. However, it should be noted that this study has some limitations, as the sample number and library coverage of analyzed oocytes were relatively low. Future studies with larger sample sizes and high-coverage libraries that examine the effects of superovulation on embryo development and offspring health as well as the underlying mechanisms are still needed.

Rhodium(iii)-catalysed cascade [3 + 2] annulation of N-aryloxyacetamides with 3-(hetero)arylpropiolic acids: synthesis of benzofuran-2(3H)-ones.

Herein, a cascade [3 + 2] annulation of N-aryloxyacetamides with 3-(hetero)arylpropiolic acids affording benzofuran-2(3H)-ones via rhodium(iii)-catalyzed redox-neutral C-H functionalization/isomerization/lactonization using an internal oxidative directing group O-NHAc was achieved. This catalytic system provides a regio- and stereoselective approach to synthesize (Z)-3-(amino(aryl)methylene)benzofuran-2(3H)-ones with exclusive Z configuration selectivity, acceptable yields and good functional group tolerance. Preliminary investigations on ultraviolet-visible and fluorescence behaviors reveal that the annulation products may be applied as a promising fluorescent probe for sensing metal cations, especially for cerium (Ce3+).

Effect of exogenous gonadotropin on the transcriptome of human granulosa cells and follicular fluid hormone profiles.

BACKGROUND: Superovulation treatment had some adverse effects on maturity and development of oocytes. Can superovulation dose of gonadotropins (Gns) affect the transcriptome of granulosa cells and follicular fluid (FF) hormone levels? METHODS: One leading pre-ovulatory follicle per subject was used from three natural-cycle and four Gn-stimulated patients. Granulosa cells and FF samples were collected from the same leading follicle of each patient. RNA was extracted from granulosa cells and subjected to deep sequencing and analysis. Follicle-stimulating hormone (FSH), estradiol (E2), androstenedione (AND), testosterone (T), luteinizing hormone (LH), and progesterone (P4) levels in FF were measured by immunoassays. Student's t test was used for statistical analysis. RESULTS: A total of 715 genes were up-regulated, and 287 genes were down-regulated, in the Gn-stimulated group relative to the control group. Gene Ontology analysis revealed that the down-regulated genes were enriched in cell cycle and meiosis pathways, primarily those associated with follicle or oocyte maturation and quality. On the other hand, the up-regulated genes were enriched in functions related to immunity and cytokine-cytokine receptor interactions. Compared to the follicles of natural cycle, the E2 and LH concentrations were significantly reduced (P < 0.001), the P4 concentration was significantly increased (P = 0.003), and the concentrations of FSH, T and AND had no difference in the follicles of Gn-stimulated cycle. CONCLUSIONS: Cell cycle- and meiosis-associated genes were down-regulated by Gns stimulation, whereas immune- and cytokine-associated genes were up-regulated. Hormone levels were also affected by Gns stimulation. Compared with natural-cycle follicles,putative markers associated with oocyte quality and follicle maturation were significantly different from those in Gn-stimulated follicles. Hormone levels in follicles were compatible with the steroidogenic patterns of granulosa cell, which reflects the follicle maturation and oocyte quality.

Asymmetric N-Hydroxyalkylation of Indoles with Ethyl Glyoxalates Catalyzed by a Chiral Phosphoric Acid: Highly Enantioselective Synthesis of Chiral N,O-Aminal Indole Derivatives.

A method of SPINOL-derived chiral phosphoric acid catalyzed asymmetric intermolecular N-hydroxyalkylation of multisubstituted indoles with ethyl glyoxalates is described in this report. This protocol provides an alternative, convenient, and direct strategy for efficient access to structurally unique α-chiral indole N,O-acyclic aminals with a broad substrate scope and good to excellent enantioselectivities. The synthetic utility of this methodology is illustrated by a gram-scale experiment and the subsequent efficient synthesis of more complex chiral N,O-aminal indole derivatives.

MicroRNA-33 protects against neointimal hyperplasia induced by arterial mechanical stretch in the grafted vein.

AIMS: Mechanical factors play significant roles in neointimal hyperplasia after vein grafting, but the mechanisms are not fully understood. Here, we investigated the roles of microRNA-33 (miR-33) in neointimal hyperplasia induced by arterial mechanical stretch after vein grafting. METHODS AND RESULTS: Grafted veins were generated by the 'cuff' technique. Neointimal hyperplasia and cell proliferation was significantly increased, and miR-33 expression was decreased after 1-, 2-, and 4-week grafts. In contrast, the expression of bone morphogenetic protein 3 (BMP3), which is a putative target of miR-33, and the phosphorylation of smad2 and smad5, which are potential downstream targets of BMP3, were increased in the grafted veins. miR-33 mimics/inhibitor and dual luciferase reporter assay confirmed the interaction of miR-33 and BMP3. miR-33 mimics attenuated, while miR-33 inhibitor accelerated, proliferation of venous smooth muscle cells (SMCs). Moreover, recombinant BMP3 increased SMC proliferation and P-smad2 and P-smad5 levels, whereas BMP3-directed siRNAs had the opposite effect. Then, venous SMCs were exposed to a 10%-1.25 Hz cyclic stretch (arterial stretch) by using the FX4000 cyclic stretch loading system in vitro to mimic arterial mechanical conditions. The arterial stretch increased venous SMC proliferation and repressed miR-33 expression, but enhanced BMP3 expression and smad2 and smad5 phosphorylation. Furthermore, perivascular multi-point injection in vivo demonstrated that agomiR-33 not only attenuates BMP3 expression and smad2 and smad5 phosphorylation, but also slows neointimal formation and cell proliferation in grafted veins. These effects of agomiR-33 on grafted veins could be reversed by local injection of BMP3 lentivirus. CONCLUSION: The miR-33-BMP3-smad signalling pathway protects against venous SMC proliferation in response to the arterial stretch. miR-33 is a target that attenuates neointimal hyperplasia in grafted vessels and may have potential clinical applications.

SIRT1 and FOXO Mediate Contractile Differentiation of Vascular Smooth Muscle Cells under Cyclic Stretch.

BACKGROUND/AIMS: Physiological mechanical stretch in vivo helps to maintain the quiescent contractile differentiation of vascular smooth muscle cells (VSMCs), but the underlying mechanisms are still unclear. Here, we investigated the effects of SIRT1 in VSMC differentiation in response to mechanical cyclic stretch. METHODS AND RESULTS: Rat VSMCs were subjected to 10%-1.25Hz-cyclic stretch in vitro using a FX-4000T system. The data indicated that the expression of contractile markers, including α-actin, calponin and SM22α, was significantly enhanced in VSMCs that were subjected to cyclic stretch compared to the static controls. The expression of SIRT1 and FOXO3a was increased by the stretch, but the expression of FOXO4 was decreased. Decreasing SIRT1 by siRNA transfection attenuated the stretch-induced expression of contractile VSMC markers and FOXO3a. Furthermore, increasing SIRT1 by either treatment with activator resveratrol or transfection with a plasmid to induce overexpression increased the expression of FOXO3a and contractile markers, and decreased the expression of FOXO4 in VSMCs. Similar trends were observed in VSMCs of SIRT1 (+/-) knockout mice. The overexpression of FOXO3a promoted the expression of contractile markers in VSMCs, while the overexpression of FOXO4 demonstrated the opposite effect. CONCLUSION: Our results indicated that physiological cyclic stretch promotes the contractile differentiation of VSMCs via the SIRT1/FOXO pathways and thus contributes to maintaining vascular homeostasis.

Phytotoxicity of umbelliferone and its analogs: Structure-activity relationships and action mechanisms.

Two coumarins, umbelliferone and daphnoretin, were isolated from roots of Stellera chamaejasme L; the former had been identified as one of the main allelochemicals in our previous studies. Both of them have the skeleton of 7-hydroxycoumarin, but showed different phytotoxic effects. Umbelliferone and its analogs were then prepared to investigate the structure-activity relationship of hydroxycoumarins and screened for phytotoxicity. The inhibitory effects varied observably in response to the coumarin derivatives, especially umbelliferone (1), 7-hydroxy-4-methylcoumarin (3) and coumarin (10) displayed strong inhibition of lettuce and two field weeds, Setaria viridis and Amaranthus retroflexus, and compounds 11 and 12 also exhibited phytotoxic activity with species specificity. The number and location of hydroxyl groups were importantly responsible for the phytotoxicity. A C7 hydroxyl group was considered to be a potentially active site and methyl substitution at the C4 position contributed significantly to the activity. The phytotoxic mechanism was briefly studied with umbelliferone by evaluating the reactive oxygen species (ROS) and chlorophylls level in lettuce seedlings. The results showed that umbelliferone induced the accumulation of ROS in the root tip and significantly decreased the chlorophyll content in the leaves. Thus, a ROS-mediated regulation pathway and the inhibition of photosynthesis were definitely involved in the phytotoxicity of umbelliferone.

Decreased HCN2 expression in STN contributes to abnormal high-voltage spindles in the cortex and globus pallidus of freely moving rats.

Abnormal oscillation in the cortical-basal ganglia loop is involved in the pathophysiology of parkinsonism. High-voltage spindles (HVSs), one of the main type abnormal oscillations in Parkinson's disease, are regulated by dopamine D2-like receptors but not D1-like receptors. However, little is known about how dopamine D2-like receptors regulate HVSs and the role of hyperpolarization-activated cyclic nucleotide-gated2 (HCN2) in HVSs regulation. We simultaneously recorded the local field potential (LFP) in globus pallidus (GP) and electrocorticogram (ECoG) in primary motor cortex (M1) in freely moving 6-hydroxydopamine (6-OHDA) lesioned or control rats. The expression of HCN2 and dopamine D2 receptor in the subthalamic nucleus (STN) was examined by immunochemical staining and Western blotting. We also tested the role of HCN2 in HVSs regulation by using pharmacological and shRNA methodology. We found that dopamine D2-like receptor agonists suppressed the increased HVSs in 6-OHDA lesioned rats. HCN2 was co-expressed with dopamine D2 receptor in the STN, and dopamine depletion decreased the expression of HCN2 as well as dopamine D2 receptor which contribute to the regulation of HVSs. HCN2 was down regulated by HCN2 shRNA, which thereby led to an increase in the HVSs in naïve rats while HCN2 agonist reduced the HVSs in 6-OHDA lesioned rats. These results suggest that HCN2 in the STN is involved in abnormal oscillation regulation between M1 cortex and GP.

Salidroside prevents cognitive impairment induced by chronic cerebral hypoperfusion in rats.

OBJECTIVE: To investigate the effects of salidroside on cognitive dysfunction induced by chronic cerebral hypoperfusion in rats. METHODS: Male Sprague-Dawley rats (n = 36) were divided into three groups (n = 12 per group): sham operation; bilateral permanent occlusion of the common carotid arteries (2-VO); 2-VO + salidroside. Rats received 20 mg/kg per day salidroside or vehicle intraperitoneal injection beginning the day before surgery and continuing until 34 days postoperatively. Cognitive function was evaluated by Morris water maze test and hippocampal long-term potentiation (LTP) measurement. Hippocampal neuronal apoptosis was evaluated via immunofluorescence. RESULTS: Chronic cerebral hypoperfusion caused marked cognitive deficit and LTP inhibition. These effects were largely ameliorated by salidroside administration. Salidroside prevented caspase-3 activation, increased the ratio of Bax/Bcl-2, and reversed hippocampal neuronal loss induced by chronic cerebral hypoperfusion. CONCLUSIONS: Salidroside prevents cognitive deficits caused by chronic cerebral hypoperfusion in rats, and alleviates apoptosis in the hippocampal CA1 area.

High frequency stimulation of the STN restored the abnormal high-voltage spindles in the cortex and the globus pallidus of 6-OHDA lesioned rats.

Many studies showed that abnormal oscillations in the cortical-basal ganglia loop is involved in the pathophysiology of Parkinson's disease (PD). In contrast to the well-studied beta synchronization, high-voltage spindles (HVSs), another type of abnormal oscillation observed in PD, are neglected. To explore the role of subthalamic nucleus-deep brain stimulation (STN-DBS) in HVSs regulation, we simultaneously recorded the local field potential (LFP) in the globus pallidus (GP) and electrocorticogram (ECoG) in the primary motor cortex(M1) in freely moving 6-hydroxydopamine (6-OHDA) lesioned or control rats before, during, and after STN-DBS. Consistent with our previous study, HVSs occurrence, duration, and relative power and coherence between the M1 cortex and GP increased in 6-OHDA lesioned rats. We found that high but not low frequency stimulation restored the abnormal HVSs activity and motor deficit. These results suggest that the STN is involved in the abnormal oscillation between the M1 cortex and GP.

Mechanism of artemisinin phytotoxicity action: induction of reactive oxygen species and cell death in lettuce seedlings.

Artemisinin has been recognized as an allelochemical that inhibits growth of several plant species. However, its mode of action is not well clarified. In this study, the mechanism of artemisinin phytotoxicity on lettuce seedlings was investigated. Root and shoot elongation of lettuce seedlings were inhibited by artemisinin in a concentration-dependent manner. The compound effectively arrested cell division and caused loss of cell viability in root tips of lettuce. Overproduction of reactive oxygen species (ROS) was induced by artemisinin. Lipid peroxidation, proline overproduction and reduction of chlorophyll content in lettuce seedlings were found after treatments. These results suggested that artemisinin could induce ROS overproduction, which caused membrane lipids peroxidation and cell death, and impacted mitosis and physiological processes, resulting in growth inhibition of receptor plants.

Involvement of BK channel in differentiation of vascular smooth muscle cells induced by mechanical stretch.

The differentiation of vascular smooth muscle cells (VSMCs), which are exposed to mechanical stretch in vivo, plays an important role in vascular remodeling during hypertension. Here, we demonstrated the mechanobiological roles of large conductance calcium and voltage-activated potassium (BK) channels in this process. In comparison with 5% stretch (physiological), 15% stretch (pathological) induced the de-differentiation of VSMCs, resulting in significantly decreased expressions of VSMC markers, i.e., α-actin, calponin and SM22. The activity of BK channels, assessed by patch clamp recording, was significantly increased by 15% stretch and was accompanied by an increased alternative splicing of BK channel α-subunit at the stress axis-regulated exons (STREX). Furthermore, transfection of whole BK or STREX-deleted BK plasmids revealed that STREX was important for BK channels to sense mechanical stretch. Using thapsigargin (TG) which induces endoplasmic reticulum (ER) stress, and xbp1-targeted siRNA transfection which blocks ER stress, the results revealed that ER stress was contribute to stretch-induced alternative splicing of STREX. Our results suggested that during hypertension, pathological stretch may induce the ER stress in VSMCs, which affects the alternative splicing and activity of BK channels, and subsequently modulates VSMC differentiation.