Melatonin Enhances Drought Tolerance in Rice Seedlings by Modulating Antioxidant Systems, Osmoregulation, and Corresponding Gene Expression.

Rice is the third largest food crop in the world, especially in Asia. Its production in various regions is affected to different degrees by drought stress. Melatonin (MT), a novel growth regulator, plays an essential role in enhancing stress resistance in crops. Nevertheless, the underlying mechanism by which melatonin helps mitigate drought damage in rice remains unclear. Therefore, in the present study, rice seedlings pretreated with melatonin (200 µM) were stressed with drought (water potential of -0.5 MPa). These rice seedlings were subsequently examined for their phenotypes and physiological and molecular properties, including metabolite contents, enzyme activities, and the corresponding gene expression levels. The findings demonstrated that drought stress induced an increase in malondialdehyde (MDA) levels, lipoxygenase (LOX) activity, and reactive oxygen species (ROS, e.g., O2- and H2O2) in rice seedlings. However, the melatonin application significantly reduced LOX activity and the MDA and ROS contents (O2- production rate and H2O2 content), with a decrease of 29.35%, 47.23%, and (45.54% and 49.33%), respectively. It activated the expression of ALM1, OsPOX1, OsCATC, and OsAPX2, which increased the activity of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), respectively. Meanwhile, the melatonin pretreatment enhanced the proline, fructose, and sucrose content by inducing OsP5CS, OsSUS7, and OsSPS1 gene expression levels. Moreover, the melatonin pretreatment considerably up-regulated the expression levels of the melatonin synthesis genes TDC2 and ASMT1 under drought stress by 7-fold and 5-fold, approximately. These improvements were reflected by an increase in the relative water content (RWC) and the root-shoot ratio in the drought-stressed rice seedlings that received a melatonin application. Consequently, melatonin considerably reduced the adverse effects of drought stress on rice seedlings and improved rice's ability to tolerate drought by primarily boosting endogenous antioxidant enzymes and osmoregulation abilities.

Differentiating atypical hemangiomas and vertebral metastases: a field-of-view (FOV) and FOCUS intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) study.

PURPOSE: Some atypical vertebral hemangiomas (VHs) may mimic metastases on routine MRI and can result in misdiagnosis and ultimately to additional imaging, biopsy and unnecessary costs. The purpose of this study is to assess the utility of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) on account of field-of-view optimized and constrained undistorted single shot (FOCUS) in distinguishing atypical VHs and vertebral metastases. METHODS: A total of 25 patients with vertebral metastases and 25 patients with atypical VHs were confirmed by clinical follow-up or pathology. IVIM-DWI imaging was performed at different b values (0, 30, 50, 100, 150, 200, 400, 600, 800, 1000 mm2/s). IVIM parameters [the true diffusion coefficient (D), pseudodiffusion coefficient (D*), standard apparent diffusion coefficient (ADC), and perfusion fraction (f)] were calculated and compared between two groups by using Student's t test. A receiver operating characteristic analysis was performed. RESULTS: Quantitative analysis of standard ADC and D parameters showed significantly lower values in vertebral metastases when compared to atypical hemangiomas [ADC value: (0.70 ± 0.12) × 10-3 mm2/s vs (1.14 ± 0.28) × 10-3 mm2/s; D value: (0.47 ± 0.07) × 10-3 mm2/s vs (0.76 ± 0.14) × 10-3 mm2/s, all P < 0.01]. The sensitivity and specificity of D value were 93.8% and 92.3%, respectively. CONCLUSION: The standard ADC value and D value may be used as an indicator to distinguish vertebral metastases from atypical VHs. FOCUS IVIM-derived parameters provide potential value in the quantitatively differentiating vertebral metastases from vertebral atypical hemangiomas.

Role of miR-489 in the proliferation and apoptosis of pancreatic carcinoma.

PURPOSE: The purpose of the present study was to detect the expression of miR-489 in pancreatic cancer (PC) tissues and cells, and to explore the effects of miR-489 on cell proliferation and apoptosis of human PC cells and to also uncover the underlying mechanism. METHODS: miR-489 expression was assessed by quantitative real time-polymerase chain reaction (qRT-PCR) in PC tissues and PANC-1 and HPDE6-C7 cell lines. The binding-site predictions by bioinformatics showed that AKT Serine/Threonine Kinase 3 (AKT3) might be a potential target of miR-489. AKT3 expression in PC tissues and cells was detected by qRT-PCR, luciferase report assay and Western blotting assay were used to verify the rationality of the target gene. The biological role of miR-489 on cell proliferation, cell cycle and apoptosis were determined in PANC-1 cells by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay and flow cytometry after transfection with miR-NC, miR-489 mimics and si-AKT3. RESULTS: Compared with normal adjacent tissues and normal pancreatic cells, the expression of miR-489 was markedly down-regulated in PC tissues and cells. AKT3 was considered as a downstream gene of miR-489 and it was found that the expression levels of miR-489 and AKT3 were inversely proportional to each other, which was further confirmed by luciferase and Western blot assays. In subsequent experiments, up-regulation of miR-489 by transfection with miR-489 mimics significantly inhibited cell proliferation, blocked the G1/S transition and induced cell apoptosis of PANC-1 cells. However, overexpression of AKT3 significantly counteracted the biological effects of miR-489. CONCLUSIONS: Our findings indicate that up-regulation of miR-489 could suppress PC cell proliferation and facilitate cell apoptosis through targeting AKT3. miR-489 and AKT3 might serve as potential targets in the therapy of PC.

Effect of Combined Acupuncture Anesthesia on Surgical Dosage and Serum IL-4, IL-10 of Pneumonectomy Patients.

OBJECTIVE: To analyse the effects of combined acupuncture anesthesia on surgical dosage and serum interleukin-4 (IL-4), interleukin-10 (IL-10) of pneumonectomy patients. STUDY DESIGN: A randomised controlled trial (RCT). PLACE AND DURATION OF STUDY: Lanzhou University Second Hospital, Lanzhou, China, from January 2016 to November 2017. METHODOLOGY: A total of 110 patients undergoing pneumonectomy were randomly divided into group A and group B, with 55 cases in each group. Group A was treated with combined 2Hz acupuncture anesthesia, while group B was treated with combined 2Hz/100Hz acupuncture anesthesia. The additional propofol, fentanyl dosage, and changes in heart rate and systolic blood pressure 5 min before and during extubation were compared between the two groups. The serum IL-4 and IL-10 levels were measured 10 minutes after skin incision and 24 hours after surgery using ELISA. Pain was rated by visual analogue scale (VAS) at 24 hours after surgery. RESULTS: There was no statistically significant difference between group A and group B in the intraoperative additional propofol and fentanyl dosags (p=0.541 and 0.719, respectively). There is no statistical difference in heart rate and systolic blood pressure between group A and group B at 5 minutes before and during extubation (p=0.151, 0.660 and 0.734, 0.528, respectively). There is no statistical difference between group A and group B in serum IL-4 and IL-10 levels 10 minutes after surgical incision (p=0.916 and 0.841, respectively). However, serum IL-4 and IL-2 levels in group A are statistically lower than that of group B at 24 hours after surgery (all p<0.001). The VAS score at 24 hours after surgery in group A was 2.44 ±0.71 points, which was significantly lower than that of group B (3.82 ±0.77 points, p<0.001). CONCLUSION: Combined 2 Hz, 2 Hz/100 Hz acupuncture anesthesia need few anesthetic dosages of propofol and fentanyl to stabilise the patient's blood pressure and heart rate when intubated under general anesthesia; but combined 2 Hz acupuncture anesthesia can reduce IL-4 and IL-10 levels during surgery stress to a greater extent than the latter, and can effectively lower patients' serum IL-4, IL-10 expression after surgery.

[Maturation regulation of dendritic cells pulsed with hepatocellular carcinoma cell soluble antigens].

OBJECTIVE: To research the maturation regulation of dendritic cells (DCs) pulsed with hepatocellular carcinoma (HCC) cell soluble antigens. METHODS: BCG HSP 70 was purified by SDS-PAGE electrophoresis and its biological activity was determined with ELISA. Phenotypes of DCs pulsed with antigens or with both antigens and BCG HSP 70 were analysed with flow cytometry. MTT assay was used to estimate the proliferation of self lymphocytes and the mixed lymphocyte reaction (MLR) of BCG HSP 70 primed DCs. RESULTS: The characteristics of DCs had changed after loaded with soluble antigens of HCC. There were about 10% DCs which had lost their specific markers. The expression levels of CD54, CD83, CD86 molecules and the stimulatory ability in allogeneic MLR decreased. However, after being activated by BCG HSP 70, the DCs pulsed with antigens could keep their special markers and the expression levels of CD54, CD83, CD86 molecules increased too. The stimulatory abilities in allogeneic MLR and proliferation of self lymphocytes also improved. CONCLUSION: This study shows that BCG HSP 70 can induce DCs pulsed with antigens maturation and improve their antigen-presenting ability, which may be a useful maturation inducer for dendritic cells.