Differential MicroRNA Expression Profiles as Potential Biomarkers for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains a clinical challenge due to its poor prognosis. Therefore, the early diagnosis of PDAC is extremely important for achieving a cure. MicroRNAs (miRNAs) could serve as a potential biomarker for the early detection and prognosis of PDAC. In this work we analyzed plasma samples from healthy persons and PDAC patients to assess differential miRNA expression profiles by next generation sequencing technology and bioinformatics analysis. In this way, 165 mature miRNAs were found to be significantly deregulated in the patient group, of which 75 and 90 mature miRNAs were up- and down-regulated compared with healthy individuals, respectively. Furthermore, 1029 novel miRNAs were identified. In conclusion, plasma miRNA expression profiles are different between healthy individuals and patients with PDAC. These data provide a possibility for use of miRNA as diagnostic and prognostic biomarkers of PDAC.

Laser Spectroscopy of Neutron-Rich Tin Isotopes: A Discontinuity in Charge Radii across the N=82 Shell Closure

The change in mean-square nuclear charge radii δ⟨r^{2}⟩ along the even-A tin isotopic chain ^{108-134}Sn has been investigated by means of collinear laser spectroscopy at ISOLDE/CERN using the atomic transitions 5p^{2} ^{1}S_{0}→5p6 s^{1}P_{1} and 5p^{2} ^{3}P_{0}→5p6s ^{3}P_{1}. With the determination of the charge radius of ^{134}Sn and corrected values for some of the neutron-rich isotopes, the evolution of the charge radii across the N=82 shell closure is established. A clear kink at the doubly magic ^{132}Sn is revealed, similar to what has been observed at N=82 in other isotopic chains with larger proton numbers, and at the N=126 shell closure in doubly magic ^{208}Pb. While most standard nuclear density functional calculations struggle with a consistent explanation of these discontinuities, we demonstrate that a recently developed Fayans energy density functional provides a coherent description of the kinks at both doubly magic nuclei, ^{132}Sn and ^{208}Pb, without sacrificing the overall performance. A multiple correlation analysis leads to the conclusion that both kinks are related to pairing and surface effects.

Concentration changes in gemcitabine and its metabolites after hyperthermia in pancreatic cancer cells assessed using RP-HPLC

Background

Gemcitabine (2′,2′-difluoro-2′-deoxycytidine;dFdC) is a first-line chemotherapy drug for pancreatic cancer. Recently, a synergistic anti-tumor treatment of dFdC and hyperthermia has achieved good clinical results, but there are few reports on the molecular mechanism influenced by hyperthermia. This study is an initial exploration of the effects of hyperthermia on changes in the concentration of dFdC and its metabolites in pancreatic cancer cells. The aim is to provide a theoretical basis for clinical detection and pharmacokinetic research.

Methods

PANC-1 cells at logarithmic growth phase were used as the experimental object. The MTT assay was performed to determine the half maximal inhibitory concentration (IC₅₀) of dFdC. After PANC-1 cells were cultured in DMEM medium containing IC₅₀dFdC and treated with hyperthermia at 41 °C or 43 °C, changes in the concentration of dFdC, 2′,2′-difluorodeoxyuridine (dFdU) and difluorodeoxycytidine triphosphate (dFdCTP) in the cells were tested using an optimized reverse phase high-performance liquid chromatography (RP-HPLC) protocol.

Results

We found that 41 °C and 43 °Chyperthermia gave rise to a decrease in dFdC and dFdU content. At 41 °C, the levels respectively fell to 9.28 and 30.93% of the baseline, and at 43 °C, to 24.76 and 57.80%, respectively. The dFdCTP content increased by 21.82% at 41 °C and 42.42% at 43 °C.

Conclusion

The two heat treatments could alter the mechanism of dFdC metabolism in PANC-1 cells. The effect of 43 °C hyperthermia is more significant. Our observations may be instrumental to explaining the higher anti-tumor efficacy of this combination therapy.

Addressing the pitfalls when designing intervention studies to discover and validate biomarkers of habitual dietary intake

INTRODUCTION

Dietary exposure monitoring within populations is reliant on self-reported measures such as Food Frequency Questionnaires and diet diaries. These methods often contain inaccurate information due to participant misreporting, non-compliance and bias. Urinary metabolites derived from individual foods could provide additional objective indicators of dietary exposure. For biomarker approaches to have utility it is essential that they cover a wide-range of commonly consumed foods and the methodology works in a real-world environment.

OBJECTIVES

To test that the methodology works in a real-world environment and to consider the impact of the major sources of likely variance; particularly complex meals, different food formulations, processing and cooking methods, as well as the dynamics of biomarker duration in the body.

METHODS

We designed and tested a dietary exposure biomarker discovery and validation strategy based on a food intervention study involving free-living individuals preparing meals and collecting urine samples at home. Two experimental periods were built around three consecutive day menu plans where all foods and drinks were provided (n = 15 and n = 36).

RESULTS

The experimental design was validated by confirming known consumption biomarkers in urinary samples after the first menu plan. We tested biomarker performance with different food formulations and processing methods involving meat, wholegrain, fruits and vegetables.

CONCLUSION

It was demonstrated that spot urine samples, together with robust dietary biomarkers, despite major sources of variance, could be used successfully for dietary exposure monitoring in large epidemiological studies.

Vegetarians have a lower fasting insulin level and higher insulin sensitivity than matched omnivores: A cross-sectional study

BACKGROUND AND AIMS

Potential associations of vegetarian diet patterns with fasting insulin (FI) and insulin sensitivity remain unclear. We aimed to investigate whether vegetarian diets were associated with FI and insulin sensitivity in a cross-sectional study in Chinese vegetarians and matched omnivores and then to test whether it is independent of body mass index (BMI).

METHODS AND RESULTS

This study included 279 vegetarians (73 vegans, 206 lacto-ovo-vegetarians) and 279 age- and sex-matched omnivores. Fasting blood glucose (FG) and FI concentrations were measured, and β-cell function (HOMA-β) and insulin resistance index (HOMA-IR) were used to evaluate insulin sensitivity. All blood glucose and insulin sensitivity indices were naturally log-transformed, and multiple-linear regression was used to determine the association between vegetarian diet patterns and insulin sensitivity after adjusting for confounders including BMI, visceral fat area, physical activity, sedentary time, income, alcohol consumption, and daily dietary intakes of macronutrients. Compared to omnivores, both vegan diet [β = -0.25, 95% CI: (-0.38, -0.14)] and lacto-ovo-vegetarian diet [β = -0.10, 95% CI: (-0.18, -0.01)] were negatively associated with HOMA-IR after adjusting for BMI. Vegan diet remained negatively associated with FI [β = -0.16, 95% CI: (-0.30, -0.01)] and HOMA-IR [β = -0.17, 95% CI: (-0.32, -0.03)] after adjusting for all confounders.

CONCLUSION

Vegetarian diet, especially vegan diet, is negatively associated with FI and IR, independent of BMI.

[Extirpation of primary malignancies in the pterygopalatine and infratemporal fossa via modified maxillary swing approach]

Five patients with primary malignancies in the pterygopalatine fossa (PPF) and infra temporal fossa (ITF) were enrolled in this retrospective study between January 2012 and January 2018. After malignancies proven by biopsy and evaluation with CT and MRI scan, all patients received modified maxillary swing (MMS) approach for extirpation of malignant tumors in the PPF and ITF under general anesthesia. En bloc resection with wide surgical margins was successfully performed in all cases. Negative margins were observed in 4 cases and positive margins were found in one patient with adenoid cystic carcinoma who received postoperative radiotherapy. The most common complication was facial numbness. During the follow-up period (range 12 to 57 months), one patient suffered from recurrence while others did not. The advantages of MMS include wide surgical field, full exposure and easy manipulation. The MMS approach is expected to become an standard method for monobloc resection of malignancies in the PPF and ITF.

Downregulation of miR-633 activated AKT/mTOR pathway by targeting AKT1 in lupus CD4+ T cells

Background

Accumulating evidence suggests that the AKT/mTOR pathway plays an important role in the pathogenesis of systemic lupus erythematosus (SLE) through activating T cells, and there are few studies looking into the role of microRNA (miRNAs) in the mechanism. We first found that miR-633 expression in CD4+T cells of SLE patients was significantly reduced.

Objective

To investigate the role of miR-633 in the AKT/mTOR pathway in lupus CD4+T cells.

Methods

Samples of 17 SLE cases and 16 healthy controls were collected to detect the expression of miR-633, AKT1, mTOR mRNA and proteins by quantitative polymerase chain reaction (qPCR) and Western-blot, respectively. To determine whether AKT1 is a direct target of miR-633, a luciferase assay was performed. In vitro, AKT1 siRNA, miR-633 mimics/inhibitors or negative controls were transfected to Jurkat cells, human primary CD4+T cells and lupus CD4+T cells. RNA and proteins were extracted after 48 h, and levels of AKT/mTOR pathway markers and downstream multiple cytokines were detected by qPCR or Western-blot.

Results

In SLE patients, the miR-633 levels in CD4+T cells were significantly decreased and negatively correlated with SLEDAI. AKT1, mTOR mRNA and proteins were all up-regulated. The degree of downregulation of miR-633 was correlated negatively with AKT1 mRNA. The luciferase assay proved that AKT1 is a direct target of miR-633. In Jurkat and lupus CD4+T cells, overexpression of miR-633 could result in lower levels of AKT1 and mTOR. Inhibition of miR-633 expression in primary CD4+T cells caused reverse effects, and protein levels of p-AKT, p-mTOR, and p-S6RP increased. Moreover, among various cytokines, the expression of IL-4, IL-17, and IFN-γ mRNA was raised.

Conclusion

Our study suggests that miR-633 deletion can activate the AKT/mTOR pathway by targeting AKT1 to participate in the pathogenesis of SLE.

Muscle specific kinase (MuSK) activation preserves neuromuscular junctions in the diaphragm but is not sufficient to provide a functional benefit in the SOD1G93A mouse model of ALS

Amyotrophic lateral sclerosis (ALS), a neurodegenerative disease affecting motor neurons, is characterized by rapid decline of motor function and ultimately respiratory failure. As motor neuron death occurs late in the disease, therapeutics that prevent the initial disassembly of the neuromuscular junction may offer optimal functional benefit and delay disease progression. To test this hypothesis, we treated the SOD1^G93A mouse model of ALS with an agonist antibody to muscle specific kinase (MuSK), a receptor tyrosine kinase required for the formation and maintenance of the neuromuscular junction. Chronic MuSK antibody treatment fully preserved innervation of the neuromuscular junction when compared with control-treated mice; however, no preservation of diaphragm function, motor neurons, or survival benefit was detected. These data show that anatomical preservation of neuromuscular junctions in the diaphragm via MuSK activation does not correlate with functional benefit in SOD1^G93A mice, suggesting caution in employing MuSK activation as a therapeutic strategy for ALS patients.

Apple rootstocks of different nitrogen tolerance affect the rhizosphere bacterial community composition

AIMS

To select apple rootstocks that are tolerant to low nitrogen and reveal the relationship between the rhizosphere bacterial communities and the low nitrogen tolerance of the apple rootstock.

METHODS AND RESULTS

In total, 235 lines of hybrids of Malus robusta Rehd. × M.9 with low nitrogen stress were cultivated in pots in a greenhouse equipped with a drip irrigation system, and growth characteristics, photosynthesis traits and mineral elements were monitored. The bacterial community structure of the rhizosphere from different rootstocks was determined via Illumina MiSeq sequencing. This study selected three low nitrogen-tolerant (NT) lines that had higher nitrogen concentration, and higher photosynthesis rate than the three low nitrogen-sensitive (NS) lines. The bacterial community structure significantly differed (P ≤ 0·001) among the rootstocks. The bacterial phyla Proteobacteria and Actinobacteria were the dominant groups in the rhizosphere and presented higher abundance in the NT rhizosphere. The N concentration in the apple rootstocks exhibited highly positive Pearson correlations with the bacterial genera Sphingomonas, Pseudoxanthomonas, Bacillus and Acinetobacter, and negative correlations with the bacterial genera Pseudarthrobacter and Bradyrhizobium.

CONCLUSIONS

This study showed that investigated rootstocks achieved increased nitrogen concentration by enhancing their photosynthetic production capacity and shaping their rhizobacteria community structure.

SIGNIFICANCE AND IMPACT OF THE STUDY

The findings provide a basis for studying the mechanisms of resistance to low nitrogen stress in apple rootstocks. Based on these beneficial bacteria, microbial inoculants can be developed for use in sustainable agricultural and horticultural production.

CYP3A4 gene polymorphism is correlated with individual consumption of sufentanil

BACKGROUND

Pain is one of the major adverse clinical outcomes of cesarean section (CS). In the past few years, researchers and physicians have been optimizing post-operative analgesic modalities, but the results are still undesirable for the parturient. The cytochrome P-450 3A4 (CYP3A4) gene has been reported to contribute significantly to human liver microsomal oxidation of sufentanil and alfentanil.

METHODS

We detected the frequency of CYP3A4 mutant allele, which is associated with the metabolism of diverse drugs, including opioids used for anesthesia. We then investigated the correlation between sufentanil (an opioid analgesic) consumption and CYP3A4 genetic polymorphism.

RESULTS

We found the frequency of the CYP3A4∗1G (the mutant form of CYP3A) variant allele to be 0.279 in 71 parturients undergoing cesarean section and 137 age-matched parturients with vaginal delivery. Interestingly, the parturients with homozygous CYP3A4∗1G showed less sufentanil consumption compared with those having the wild-type genotype.

CONCLUSION

In summary, we found a correlation between CYP3A4 genetic polymorphism and sufentanil consumption. This might be helpful for optimizing the anesthesia strategies and reducing their side effects.

[Change in peripheral nervous conduction velocity in patients with occupational chronic mercury poisoning and related influencing factors]

Objective: To investigate the change in peripheral nervous conduction velocity in patients with occupational chronic mercury poisoning and related influencing factors. Methods: From February 2011 to December 2014, urinary mercury examination and neural electromyography were performed for 104 patients with occupational chronic mercury poisoning. The data on age, type of work, working years of mercury exposure, and past medical history were collected, and peripheral nervous conduction velocity and its correlation with age, working years of mercury exposure, and urinary mercury concentration were analyzed. Results: All the 104 patients with occupational chronic mercury poisoning had a mean of 45.37±9.82 years, median (P(25), P(75)) working years of 7 (3, 11) , and a median (P(25), P(75)) urinary mercury concentration of 88.50 (56.25, 163.03) μg/g Cr. The major clinical manifestations of peripheral nerve injuries were numbness of extremities (20.2%) , hypopselaphesia/hypalgesia or hyperpselaphesia/hyperalgesia (9.6%) , and bone/muscle pain in the extremities (6.7%) . Neural electromyography showed an increase in denervation potential (fibrillation potential or positive sharp wave) and a detection rate of abnormal peripheral nervous conduction velocity as high as 65.4%. The patients with an older age and more working years had a higher incidence rate of abnormal sensory conduction velocity of the ulnar nerve. There were significant reductions in motor and sensory conduction velocities of the median nerve, motor and sensory conduction velocities of the ulnar nerve, motor conduction velocity of the common peroneal nerve, and the sensory conduction velocity of the superficial peroneal nerve (P<0.05) , with the increase in urinary mercury concentration. Conclusion: Patients with occupational mercury poisoning have a high rate of abnormal neural electromyographic findings, which can be used as an important method for early identification of chronic peripheral nerve injuries induced by mercury poisoning. The degree of peripheral nerve injuries increases with the increasing time of mercury exposure and urinary mercury concentration.

[Analysis of clinical features in patients with pneumoconiosis complicated with pulmonary emphysema]

Objective: To investigate the clinical features of pneumoconiosis complicated with pulmo-nary emphysema. Methods: selected 868 patients with pneumoconiosis were selected from December 2015 to December 2016 in Hunan occupational disease prevention and treatment hospital. Collected the results of high-resolution spiral CT, arterial blood gas, ECG, pulmonary function and MRC score. The subjects were divided into pneumoconiosis complicated with pulmonary emphysema group and simple pneumoconiosis group accord-ing to the results of HRCT. The smoking, MRC score, pulmonary function, blood gas and complications were compared. Results: A total of 868 patients were enrolled in the study. Emphysema 232 people, accounting for 26.73%. The incidence of emphysema in the first phase of pneumoconiosis was 12.69%, and the incidence rate of emphysema in pneumoconiosis was 17.03%, The incidence of three Stage pneumoconiosis was highest, up to 60.76%, the incidence of emphysema increased with the increase of stages of pneumoconiosis (P=0.000) .The smoking index of pneumoconiosis combined with emphysema group was significantly higher than that of simple pneumoconiosis group (P<0.01) . The MRC score of pneumoconiosis complicated with pulmonary em-physema group was higher than that of simple pneumoconiosis group (P=0.000) . In pneumoconiosis complicat-ed with pulmonary emphysema group the FEV(1.0)%, FVC%, FEV(1.0)/FVC, DLCO%, oxygen partial pressure were significantly lower than that of simple pneumoconiosis group (P≤0.05) . The combined rate of Bullae of lung in pneumoconiosis complicated with pulmonary emphysema group was higher than that of simple pneumo-coniosis group (P<0.01) . Conclusion: pneumoconiosis stage and smoking. Patients with pneumoconiosis com-plicated with pulmonary emphysema had heavier breathing difficulties, more serious pulmonary function and active endurance, the degree of hypoxia is more serious, and had a higher incidence of complications. The pul-monary function of pneumoconiosis complicated with pulmonary emphysema is not consistent with the typical CPFE.

Micro-CT imaging and structural analysis of glomeruli in a model of Adriamycin-induced nephropathy

Glomeruli number and size are important for determining the pathogenesis of glomerular disease, chronic kidney disease, and hypertension. Moreover, renal injury can occur in specific cortical layers and alter glomerular spatial distribution. In this study, we present a comprehensive structural analysis of glomeruli in a model of Adriamycin (doxorubicin) nephropathy. Glomeruli are imaged (micro-CT at 10 × 10 × 10 μm³) in kidney specimens from C57Bl/6 mouse cohorts: control treated with saline ( n = 9) and Adriamycin treated with 20 mg/kg Adriamycin ( n = 7). Several indices were examined, including glomerular number, glomerular volume, glomerular volume heterogeneity, and spatial density at each glomerulus and in each cortical layer (superficial, midcortical, and juxtamedullary). In the Adriamycin-treated animals, glomerular number decreased significantly in the left kidney [control: 8,298 ± 221, Adriamycin: 6,781 ± 630 (mean ± SE)] and right kidney (control: 7,317 ± 367, Adriamycin: 5,522 ± 508), and glomerular volume heterogeneity increased significantly in the left kidney (control: 0.642 ± 0.015, Adriamycin: 0.786 ± 0.018) and right kidney (control: 0.739 ± 0.016, Adriamycin: 0.937 ± 0.023). Glomerular spatial density was not affected. Glomerular volume heterogeneity increased significantly in the superficial and midcortical layers of the Adriamycin cohort. Adriamycin did not affect glomerular volume or density metrics in the juxtamedullary region, suggesting a compensatory mechanism of juxtamedullary glomeruli to injury in the outer cortical layers. Left/right asymmetry was observed in kidney size and various glomeruli metrics. The methods presented here can be used to evaluate renal disease models with subtle changes in glomerular endowment locally or across the entire kidney, and they provide an imaging tool to investigate diverse interventions and therapeutic drugs.

De novo mutations of STXBP1 in Chinese children with early onset epileptic encephalopathy

To detect syntaxin-binding protein 1 (STXBP1) mutations in Chinese patients with early onset epileptic encephalopathy (EOEE) of unknown etiology. Targeted next-generation sequencing was used to identify STXBP1 mutations in 143 Chinese patients with EOEE of unknown etiology. A filtering process was applied to prioritize rare variants of potential functional significance. Then Sanger sequencing was employed to validate the parental origin of the variants. Detailed clinical and genetic data were collected for 9 STXBP1-positive patients. Eight de novo heterozygous STXBP1 mutations were identified in 9 patients; 5 were novel mutations (c.1155delC, c.1030-1G>A, c.217G>C, c.268G>C, c.1480_1481 insT) and 3 were previously reported (c.1216C> T, c.1217G>A [2 cases], c.875G>A). Two patients had Ohtahara syndrome and 1 had West syndrome at onset, whereas the other 6 presented with EOEE that did not fit a specific recognized epilepsy syndrome. Six of these patients later evolved to West syndrome. All but 2 cases were prescribed more than 2 antiepileptic drugs (AEDs) plus other regimens. Four subjects showed good responses to levetiracetam (LEV) alone or in combination with other AEDs, and one case (1/3) achieved complete freedom from seizures with a ketogenic diet (KD). All patients exhibited severe to profound global developmental delay. Five novel heterozygous de novo STXBP1 mutations were discovered in patients with EOEE from China. STXBP1 mutational analysis should be performed in cases of EOEE of unknown etiology. LEV as monotherapy or adjunctive therapy with other regimens, as well as KD should be considered for management of this patient group.

[Two-year clinical and radiological outcomes of minimally invasive surgery for severe adult degenerative scoliosis]

Objectives: To evaluate the efficacy of restoring the balance in the coronal and sagittal planes and to evaluate clinical outcomes in the treatment of severe adult degenerative scoliosis patients using staged lateral lumbar interbody fusion (LLIF) and percutaneous transpedicle screw fixation (pTSF). Methods: A retrospective analysis was made on 13 patients with severe adult degenerative scoliosis treated with staged surgery in Ruijin Hospital between May, 2014 and July, 2015. The operation data were collected, including operation time, estimated blood loss, and complications. Preoperative and postoperative standing anteroposterior and lateral lumbar radiographs were obtained by EOS image system in all patients for measurement of sagittal and coronal plane alignment. All patients were available for at least 24 months of following-up (18-32 months). Paired sample t test was used to compare the parameters of each group pre- and post-operation. Results: All of the 13 patients received LLIF with staged transpedicle screw fixation. Mean operation time was (231±48) minutes and (155±33) minutes for two-stage surgery. Mean blood loss was (253±80) ml during one-stage LLIF surgery and (326±99) ml during two-stage pTSF surgery. The interval between two surgical procedures was from 7 to 42 days (mean 14 days). In the coronal plane, the mean Cobb angle of curves was 43.1°±7.3° preoperatively, and it was 11.4°±4.0°after one-stage LLIF (t=10.16, P<0.001) and 5.5°±1.9° after two-stage pTSF (t=6.14, P<0.001). In the sagittal plane, lumbar lordosis (LL) changed after each procedure was as follows: LLIF from 16.8°±8.4° to 30.1°±6.8° (t=5.21, P<0.001) and PSF to 37.1°±4.0° (t=5.04, P<0.001). Sagittal vertical axis (SVA) was reduced from (10.5±2.4) cm to (5.3±2.1) cm after one-stage LLIF (t=8.52, P<0.001) and to (3.1±1.5) cm after two-stage pTSF (t=5.51, P<0.001). In the spino-pelvic parameter, pelvic incidence(PI)-LL mismatch decreased from 33.6°±9.6° to 17.8°±4.5° (t=5.31, P<0.001) after LLIF and to 9.9°±3.7° after pTSF (t=4.68, P<0.001). The visual analogue scale (VAS) of low back pain and leg pain and the Oswestry dability Index (ODI) improved significantly at the last follow-up (t=10.42, 8.94, 19.20, all P<0.01). Conclusions: LLIF significantly improves segmental and coronal plane alignment in patients with degenerative lumbar scoliosis, and these patients can be effectively corrected by staged minimally invasive surgery.

Overexpressed Sirt1 in MSCs Promotes Dentin Formation in Bmi1-Deficient Mice

Sirt1 promotes odontoblastic gene expression in human dental pulp cells, whereas the inhibition of Sirt1 downregulates the expression of those genes. To investigate whether the overexpression of Sirt1 in mesenchymal stem cells (MSCs) driven by Prx1 promoter could rescue the dentin formation defects in Bmi1-deficient (Bmi1^-/-) mice, we established the MSCs overexpressing Sirt1 in Bmi1 knockout mice (Sirt1^TGBmi1^-/-). First, we used Prx1-Cre/ROSA^nTnG mice to demonstrate that Prx1 linage cells exist mainly in the pulp horns at 4 wk of age. Second, we found that 4-wk-old Sirt1^TG mice had increased tooth volume as compared with wild-type (WT) littermates. The expression level of Sirt1 was significantly higher in dental papilla mesenchymal cells of Sirt1^TG mice than WT mice. Furthermore, we demonstrated that the tooth mineralization, dental volume, dentin sialoprotein-immunopositive areas, odontoblastic gene expression, and percentage of proliferating BrdU-positive cells were significantly elevated in the Sirt1^TG mice and dramatically reduced in the Bmi1^-/- mice versus the WT littermates at 4 wk of age. However, the areas of predentin and the percentage of TUNEL-positive apoptotic cells were significantly reduced in the Sirt1^TG mice but dramatically increased in the Bmi1^-/- mice as compared with the WT littermates. All these parameters were rescued in the Sirt1^TGBmi1^-/- mice versus the Bmi1^-/- mice. Finally, by using dental papilla mesenchymal cells, we found that the overexpression of Sirt1 rescued the reduced cell proliferation and differentiation and increased the cell apoptosis caused by Bmi1 deficiency, which was associated with increased p53 deacetylation. Therefore, this study indicates that Sirt1 is a potential therapeutic target for promoting dentin formation in an anabolic approach to the treatment of dental developmental defects.

Genomic and phylogenetic evidence that Maize rough dwarf and Rice black-streaked dwarf fijiviruses should be classified as different geographic strains of a single species

Maize rough dwarf disease (MRDD) has long been known as one of the most devastating viral diseases of maize worldwide and is caused by single or complex infection by four fijiviruses: Maize rough dwarf virus (MRDV) in Europe and the Middle East, Mal de Rio Cuarto virus (MRCV) in South America, rice black-streaked dwarf virus (RBSDV), and Southern rice black-streaked dwarf virus (SRBSDV or Rice black-streaked dwarf virus 2, RBSDV-2) in East Asia. These are currently classified as four distinct species in the genus Fijivirus, family Reoviridae, but their taxonomic status has been questioned. To help resolve this, the nucleotide sequences of the ten genomic segments of an Italian isolate of MRDV have been determined, providing the first complete genomic sequence of this virus. Its genome has 29144 nucleotides and is similar in organization to those of RBSDV, SRBSDV, and MRCV. The 13 ORFs always share highest identities (81.3-97.2%) with the corresponding ORFs of RBSDV and phylogenetic analyses of the different genome segments and ORFs all confirm that MRDV clusters most closely with RBSDV and that MRCV and SRBSDV are slightly more distantly related. The results suggest that MRDV and RBSDV should be classified as different geographic strains of the same virus species and we suggest the name cereal black-streaked dwarf fijivirus (CBSDV) for consideration.

[Effect of S1PR2 inhibition on epithelial ovarian cancer SKOV3 cell proliferation in vitro and in vivo]

Objective: To study the effect and mechanism of S1PR2 inhibition on epithelial ovarian cancer SKOV3 cell proliferation in vitro and in vivo. Methods: (1) A pair of S1PR2 gene small interference RNA (siRNA) , namely si-S1PR2, and a pair of negative control siRNA were designed. Western blot methods were used to detect the silence efficiency of the S1PR2 in the si-S1PR2 group, blank control group and negative control group. (2) Study in vitro: the experiment included three groups, namely si-S1PR2 group, blank control group and negative control group. Cell counting kit-8 (CCK-8) assay was used to detect the proliferation inhibition rates of the transfected cells. The cell cycles of the transfected cells were measured by flow cytometry. Western blot was used to detect the levels of phosph-extracellular regulated protein kinase 1/2 (p-ERK1/2) of the transfected cells. (3) Study in vivo:to establish intraperitoneal transplantation models, 8 mice in each group were intraperitoneally injected with 5×10(6) SKOV3 cells. Phosphate buffered saline (PBS) or JTE-013 were administered into mice twice per week starting on day 7 after the injection of the cancer cells. Twenty-eight days after nude mice intraperitoneal injection with JTE-013 or PBS, the mice were sacrificed and the number and the weight of visible tumors were calculated. Results: (1) The results of western blot showed that the relative S1PR2 protein expression levels were 0.24±0.04 in the si-S1PR2 group, which was lower than that in the blank control group (1.10±0.14, P<0.01) and negative control group (1.07±0.13, P<0.01) . (2) The results of CCK-8 assay indicated that after transfected for 24, 48 and 72 hours, the proliferation inhibition rate of si-S1PR2 group were respectively (26.6±3.3) %, (35.0±3.4) %, and (34.0±2.8) %, significantly lower than those in the blank control group (all 0; all P<0.01) and negative control group [ (1.7±0.9) %, (2.5±0.5) %,and (2.4±1.1) % respectively; all P<0.01]. The results of flow cytometry showed that the G(0)/G(1) ratio in the si-S1PR2 group [ (70.9±2.8) %] was significantly higher than those in the blank control group [ (61.7±2.4) %, P<0.01] and negative control group [ (62.1±3.3) %, P<0.01]. Western blot showed that the relative expression level of p-ERK1/2 in si-S1PR2 group (0.11±0.03) was significantly lower than those in the blank control group [ (0.62±0.09) , P<0.01] and negative control group [ (0.68±0.09) , P<0.01]. (3)Twenty-eight days after nude mice intraperitoneal injection with JTE-013 or PBS, the tumor number of the control group and JTE-013 group were respectively 15.4±4.3 and 8.2±3.7, the tumor weight were (0.45±0.12) and (0.21±0.07) g, respectively. The tumor number and weight in the JTE-013 group were significantly less than those in the control group (all P<0.01) . Conclusions: The growth of ovarian cancer cells could be decreased by S1PR2 inhibition in vitro and in vivo. One of the mechanisms of the growth inhibitory effect is probably that S1PR2 inhibition lower the phosphorylation level of extracellular regulated protein kinase 1/2 (ERK1/2) pathway, which prevent the transformation of ovarian cancer cells from phase G(1) to S.