N-Doping Coupled with Co-Vacancies Activating Sulfur Atoms and Narrowing Bandgap for CoS Toward Synergistically Accelerating Hydrogen Evolution.

The combination of hetero-elemental doping and vacancy engineering will be developed as one of the most efficient strategies to design excellent electrocatalysts for hydrogen evolution reaction (HER). Herein, a novel strategy for N-doping coupled with Co-vacancies is demonstrated to precisely activate inert S atoms adjacent to Co-vacancies and significantly improve charge transfer for CoS toward accelerating HER. In this strategy, N-doping favors the presence of Co-vacancies, due to greatly decreasing their formation energy. The as-developed strategy realizes the upshift of S 3p orbitals followed by more overlapping between S 3py and H 1s orbitals, which results in the favorable hydrogen atom adsorption free energy change (ΔGH ) to activate inert S atoms as newborn catalytical sites. Besides, this strategy synergistically decreases the bandgap of CoS, thereby achieving satisfactory electrical conductivity and low charge-transfer resistance for the as-obtained electrocatalysts. With an excellent HER activity of -89.0 mV at 10.0 mA cm-2 in alkaline environments, this work provides a new approach to unlocking inert sites and significantly improving charge transfer toward cobalt-based materials for highly efficient HER.

Engineering Rich Active Sites and Efficient Water Dissociation for Ni-Doped MoS2/CoS2 Hierarchical Structures toward Excellent Alkaline Hydrogen Evolution.

Besides improving charge transfer, there are two key factors, such as increasing active sites and promoting water dissociation, to be deeply investigated to realize high-performance MoS2-based electrocatalysts in alkaline hydrogen evolution reaction (HER). Herein, we have demonstrated the synergistic engineering to realize rich unsaturated sulfur atoms and activated O-H bonds toward the water for Ni-doped MoS2/CoS2 hierarchical structures by an approach to Ni doping coupled with in situ sulfurizing for excellent alkaline HER. In this work, the Ni-doped atoms are evolved into Ni(OH)2 during alkaline HER. Interestingly, the extra unsaturated sulfur atoms will be modulated into MoS2 nanosheets by breaking Ni-S bonds during the formation of Ni(OH)2. On the other hand, the higher the mass of the Ni precursor (mNi) for the fabrication of our samples, the more Ni(OH)2 is evolved, indicating a stronger ability for water dissociation of our samples during alkaline HER. Our results further reveal that regulating mNi is crucial to the HER activity of the as-synthesized samples. By regulating mNi to 0.300 g, a balance between increasing active sites and promoting water dissociation is achieved for the Ni-doped MoS2/CoS2 samples to boost alkaline HER. Consequently, the optimal samples present the highest HER activity among all counterparts, accompanied by reliable long-term stability. This work will promise important applications in the field of electrocatalytic hydrogen evolution in alkaline environments.

Palladium-catalyzed Heck-carbonylation of alkene-tethered carbamoyl chlorides with aryl formates.

We report a palladium-catalyzed Heck-carbonylation of alkene-tethered carbamoyl chlorides by utilizing aryl formates as convenient CO surrogates. One C-O and two C-C bonds are constructed to give diversiform esterified oxindoles/γ-lactams bearing an all-carbon quaternary stereocenter under gas-free conditions. This transformation features a wide substrate scope and good functional group tolerance and can be easily applied to late-stage functionalization.

Oxidative Modification of miR-184 Enables It to Target Bcl-xL and Bcl-w.

MicroRNAs (miRNAs) are small non-coding RNAs, and they bind to complementary sequences in the three prime untranslated regions (3' UTRs) of target mRNA transcripts, thereby inhibiting mRNA translation or promoting mRNA degradation. Excessive reactive oxygen species (ROS) can cause cell-damaging effects through oxidative modification of macromolecules leading to their inappropriate functions. Such oxidative modification is related to cancers, aging, and neurodegenerative and cardiovascular diseases. Here we report that miRNAs can be oxidatively modified by ROS. We identified that miR-184 upon oxidative modification associates with the 3' UTRs of Bcl-xL and Bcl-w that are not its native targets. The mismatch of oxidized miR-184 with Bcl-xL and Bcl-w is involved in the initiation of apoptosis in the study with rat heart cell line H9c2 and mouse models. Our results reveal a model of ROS in regulating cellular events by oxidatively modifying miRNA.

A prospective cohort study of the risk factors for new falls and fragility fractures in self-caring elderly patients aged 80 years and over.

BACKGROUND: This study aimed to prospectively analyze the risk factors for new falls and fragility fractures in self-caring elderly patients and to find suitable evaluation tools for community screening and follow-up interventions. METHODS: A total of 300 participants (187 male and 113 female), aged 80 or above and capable of caring for themselves, were enrolled in this study and observed for a period of 12 months. Their medical histories were collected, various indicators were measured, and the risk factors for new falls and fragility fractures were analyzed. RESULTS: A total of 290 participants were included in the statistical analysis. Eighty-seven participants (30%) had new falls. The incidence was negatively correlated with the activities of daily living (ADL, represented by the Barthel Index) score (P=0.008) but was positively correlated with the timed up-and-go (TUG) test score> 12 s (P=0.021). The results also revealed that 33 fragility fractures occurred in 29 patients (10.0%), which was positively correlated with new falls (P=0.000). New fragility fractures were negatively correlated with the bone mineral density (BMD) of the lumbar vertebrae (P=0.012) and walking speed (P=0.000). CONCLUSION: TUG, walking speed, the ADL score, and the fall risk assessment scale can simply and effectively assess the risk of new falls and fragility fractures in the elderly population, and their use should be widely implemented in the community.

Hepatic portal venous gas: A case report and analysis of 131 patients using PUBMED and MEDLINE database.

OBJECTIVE: Hepatic portal pneumatosis has a high mortality rate, and whether surgical intervention is necessary remains controversial. This experiment retrospectively analyzed the etiology, treatment methods and prognosis of adult patients with hepatoportal pneumocele to provide a theoretical basis for the treatment of this disease. METHODS: We analyzed the clinical symptoms and post-treatment of a 43-year-old male patient with HPVG admitted to hospital. We retrieved adult non-iatrogenic HPVG cases with complete clinical data in PUBMED,  and MEDLINE and other databases were retrieved for analysis, and summarized the pathogenesis, clinical symptoms, pathogenesis, pathogenesis and prognosis of different treatment schemes were summarized. RESULTS: The main etiology of HPVG are intestinal ischemia (27%), severe enteritis/intestinal perforation/intestinal fistula (16%), intestinal obstruction (7%), abdominal infection (7%), gastric diseases (11%), appendicitis and its complications (5%), acute hemorrhage or necrotizing pancreatitis (5%), Crohn's disease and its complications (4%), trauma (traffic accidents, falls) (2%), diverticulitis and perforation (6%), nephrogenic diseases (4%), spontaneous pneumohepatic portal vein (2%), other reasons (4%). And after analysis, we found that the survival rate of patients treated by surgery was 40.5% and the mortality rate was 19.1%, the difference between the two was significant. CONCLUSIONS: Etiology should be actively explored and surgical treatment is necessary.

Betulin isolated from Pyrola incarnata Fisch. inhibited lipopolysaccharide (LPS)-induced neuroinflammation with the guidance of computer-aided drug design.

This study aims to investigate active phytochemicals isolated from Pyrola incarnata Fisch. (P. incarnata) and their protection against neuroinflammation induced by LPS. Betulin, accompanied with other 9 compounds, were isolated from P. incarnata and elucidated by spectroscopic analysis (1H-, 13C NMR). ELISA kits and the measurement of NO production based on Griess reaction showed that betulin (5) (250 µg/mL) could suppress LPS-induced activation of microglial cell BV-2 better than others by inhibiting inflammatory cytokines (TNF-α, IL-6, IL-1ß) expression and NO production. With the guidance of computer-aided drug design and the analysis of biological experiment, we demonstrated betulin could reduce LPS-induced iNOS expression, prevent JNKs pathways, and down-regulate the phosphorylation levels of NF-κB/p65. In conclusion, betulin isolated from P. incarnata possessed outstanding anti-neuroinflammation potential, presumably related to iNOS expression, JNKs and NF-κB/p65 pathways. Therefore, Pyrola incarnata may be a valuable natural resource and betulin is a potential drug for the treatment of neurodegenerative disorders by inhibiting inflammatory mediators.

Pyrola incarnata demonstrates neuroprotective effects against ß-amyloid-induced memory impairment in mice.

This study aims to investigate the neuroprotective effects of Pyrola incarnata against ß-amyloid-induced memory impairment in mice. Ethanol extract of Pyrola incarnata (EPI) was obtained and led to eleven phytochemicals successfully by isolation and purification, which were elucidated by spectroscopic analysis (1H NMR, 13C NMR and HR-ESI-MS). Thereinto, ursolic acid was gained as most abundant monomer. C57BL/6 mice were intracerebroventricular injected with aggregated Aß25-35. Open-field test, Barnes maze test and Morris water maze were conducted for evaluating cognition processes of EPI and ursolic acid. EPI significantly improved learning and memory deficits, attenuated the Aß25-35 level of deposition immunohistochemically. Further studies revealed that ursolic acid as bioactive phytochemical of P. incarnata improved spatial memory performance and ameliorated Aß25-35 accumulation by activating microglia cells and up-regulating Iba1 level in the hippocampus. These findings suggest P. incarnata could improve the cognition of mice and be a promising natural source for the treatment of neurodegenerative disease.

Alterations in intra- and internetwork functional connectivity associated with levetiracetam treatment in temporal lobe epilepsy.

OBJECTIVE: Levetiracetam (LEV) is an antiepileptic drug with a novel pharmacological mechanism. Advances in functional magnetic resonance imaging (fMRI) enable researchers to explore the cognitive effects of antiepileptic drugs on the living brain. This study aimed to explore how the functional connectivity patterns of the cognitive networks changed in association with LEV treatment. METHODS: Patients with temporal lobe epilepsy (TLE), including both users and nonusers of LEV, were included in this study along with healthy controls. Core cognitive networks were extracted using an independent component analysis approach. Functional connectivity patterns within and between networks were investigated. The relationships between functional connectivity patterns and clinical characteristics were also examined. RESULTS: The patterns of intranetwork connectivity in the default mode network (DMN), left executive control network (lECN), and dorsal attention network (DAN) differed among the three groups. The internetwork interactions did not show intergroup differences once corrected for multiple comparisons. No correlation between functional connectivity and clinical characteristics was found in patients with TLE. CONCLUSIONS: Changes in intranetwork connectivity are a key effect of LEV administration. SIGNIFICANCE: Alterations in intranetwork connectivity patterns may underlie the cognitive effects of LEV administration; this finding improves our understanding of the neural mechanisms of LEV therapy.

Identification of cis-regulatory regions responsible for developmental and hormonal regulation of HbHMGS1 in transgenic Arabidopsis thaliana.

OBJECTIVES: 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase (HMGS) is an important enzyme in mevalonate (MVA) pathway of isoprenoid biosynthesis, which regulates the rubber biosynthetic pathway in rubber tree (Hevea brasiliensis) in coordination with HMG-CoA reductase (HMGR). However, little information is available about the regulation of HMGS gene expression. To understand the mechanism controlling the HbHMGS1 gene expression, we characterized the HbHMGS1 promoter sequence in transgenic plants with the ß-glucuronidase (GUS) reporter gene. RESULTS: GUS activity analysis of the transgenic plants showed that the HbHMGS1 promoter is active in all organs of the transgenic Arabidopsis plants during various developmental stages (from 6 to 45-day-old). Deletion of different portions of the upstream HbHMGS1 promoter identified sequences responsible for either positive or negative regulation of the GUS expression. Particularly, the - 454 bp HbHMGS1 promoter resulted in a 2.19-fold increase in promoter activity compared with the CaMV 35S promoter, suggesting that the - 454 bp HbHMGS1 promoter is a super-strong near-constitutive promoter. In addition, a number of promoter regions important for the responsiveness to ethylene, methyl jasmonate (MeJA) and gibberellic acid (GA) were identified. CONCLUSION: The - 454 bp HbHMGS1 promoter has great application potential in plant transformation studies as an alternative to the CaMV 35S promoter. The HbHMGS1 promoter may play important roles in regulating ethylene-, MeJA- and GA-mediated gene expression. The functional complexity of cis-elements revealed by this study remains to be elucidated.

Induction of apomixis by dimethyl sulfoxide (DMSO) and genetic identification of apomictic plants in cassava.

Apomixis, or asexual seed formation, is of great value for plant breeding and seed production, and is desirable in modern agriculture, but natural apomixis occurs in cassava at very low frequency. In present study, apomixis was induced by the treatments of female flower buds with 1%, 1.5% and 2% (v/v) dimethyl sulfoxide (DMSO) and the results showed that 1.5% DMSO treatment was most effective for the induction of apomictic seed formation in cassava cultivar SC5 with the highest percentages of fruit set and true apomictic seeds. The germinated seedlings resembled their parents and displayed no morphological characteristics of cassava polyploid. Flow cytometry and chromosome counting showed that these plants were uniform diploids. Analysis of 34 DMSO-induced cassava progenies by the expressed sequence tag-simple sequence repeat (EST-SSR) and sequence-related amplified polymorphism (SRAP) markers showed that three true apomictic seeds were obtained from the group of SC5 treated with 1.5% DMSO.

Transcriptome analysis of Hevea brasiliensis in response to exogenous methyl jasmonate provides novel insights into regulation of jasmonate-elicited rubber biosynthesis.

The phytohomorne methyl jasmonate (MeJA) is known to trigger extensive reprogramming of gene expression leading to transcriptional activation of many secondary metabolic pathways. However, natural rubber is a commercially important secondary metabolite and little is known about the genetic and genomic basis of jasmonate-elicited rubber biosynthesis in rubber tree (Hevea brasiliensis). RNA sequencing (RNA-seq) of H. brasiliensis bark treated with 1 g lanolin paste containing 0.02% w/w MeJA for 24 h (M2) and 0.04% w/w MeJA for 24 h (M4) was performed. A total of 2950 and 2850 differentially expressed genes in M2 and M4 compared with control (C) were respectively detected. Key genes involved in 2-C-methyl-D-erythritol 4-phosphate, rubber biosynthesis, glycolysis and carbon fixation (Calvin cycle) pathway were found to be up-regulated by MeJA treatment. Particularly, the expression of 3-hydroxy-3-metylglutaryl coenzyme A reductase in MVA pathway was down-regulated by MeJA treatment, but the expression of farnesyl diphosphate synthase (FPS) and cis-prenyltransferase (CPT, or rubber transferase) in rubber biosynthesis pathway were up-regulated by MeJA treatment. Up-regulation of critical genes in JA biosynthesis in response to MeJA treatment exhibited the self-activation of JA biosynthesis. In addition, up-regulated genes of great regulatory importance in cross-talk between JA and other hormone signaling, and of transcriptional regulation were identified. The increased expression levels of FPS and CPT in rubber biosynthesis pathway possibly resulted in an increased latex production in rubber tree treated with MeJA. The present results provide insights into the mechanism by which MeJA activates the rubber biosynthesis and the transcriptome data can also serve as the foundation for future research into the molecular basis for MeJA regulation of other cellular processes.

[Absorbed components analysis of Zhitong Huazheng Capsules in rat serum by UPLC-Q-TOF/MS].

To identify and analyze the constituents in rat serum after oral administration of Zhitong Huazheng capsule (ZTHZC), and provide a reference for its further research on pharmacodynamics material basis. Female Wistar rats were selected as experimental animals, and received intragastric administration of ZTHZC at a dose of 1.5 g·kg⁻¹. After the serum samples were collected, the absorbed prototype components in rat serum were identified and analyzed by using ultra-high performance liquid chromatography-quadrupole-time-of-flight/mass spectrometry (UPLC-Q-TOF/MS) combined with multivariate statistical analysis．The results showed, a total of fifteen absorbed constituents were identified, all of which were prototype components, including Danshensu, salvianolic acid A, B, C, D, 9,12-dihydroxy-15-nonadecanoicacid, linoleic acid, ethyl palmitoleate, tetrahydropalmatine, fumarate A, astragaloside A, astragaloside II, saponin, locustin and luteolin. This experiment showed that these fifteen components absorbed into blood may be the potential bioactive components in ZTHZC, providing a scientific basis for clarifying its material basis in pharmacodynamics.

Highly efficient mesophyll protoplast isolation and PEG-mediated transient gene expression for rapid and large-scale gene characterization in cassava (Manihot esculenta Crantz).

BACKGROUND: Cassava (Manihot esculenta Crantz) is a major crop extensively cultivated in the tropics as both an important source of calories and a promising source for biofuel production. Although stable gene expression have been used for transgenic breeding and gene function study, a quick, easy and large-scale transformation platform has been in urgent need for gene functional characterization, especially after the cassava full genome was sequenced. METHODS: Fully expanded leaves from in vitro plantlets of Manihot esculenta were used to optimize the concentrations of cellulase R-10 and macerozyme R-10 for obtaining protoplasts with the highest yield and viability. Then, the optimum conditions (PEG4000 concentration and transfection time) were determined for cassava protoplast transient gene expression. In addition, the reliability of the established protocol was confirmed for subcellular protein localization. RESULTS: In this work we optimized the main influencing factors and developed an efficient mesophyll protoplast isolation and PEG-mediated transient gene expression in cassava. The suitable enzyme digestion system was established with the combination of 1.6% cellulase R-10 and 0.8% macerozyme R-10 for 16 h of digestion in the dark at 25 °C, resulting in the high yield (4.4 × 107 protoplasts/g FW) and vitality (92.6%) of mesophyll protoplasts. The maximum transfection efficiency (70.8%) was obtained with the incubation of the protoplasts/vector DNA mixture with 25% PEG4000 for 10 min. We validated the applicability of the system for studying the subcellular localization of MeSTP7 (an H+/monosaccharide cotransporter) with our transient expression protocol and a heterologous Arabidopsis transient gene expression system. CONCLUSION: We optimized the main influencing factors and developed an efficient mesophyll protoplast isolation and transient gene expression in cassava, which will facilitate large-scale characterization of genes and pathways in cassava.

Relationship between mammographic calcifications and the clinicopathologic characteristics of breast cancer in Western China: a retrospective multi-center study of 7317 female patients.

BACKGROUND AND PURPOSE: Limited information is available regarding the correlations between mammographic calcifications and the epidemiological features of patients with breast cancer living different lifestyles in Western China. Thus, this study aimed to investigate the relationship between mammographic calcifications and the epidemiological characteristics of female patients with breast cancer in Western China. METHODS: This was a hospital-based, retrospective, multi-center epidemiological study of patients with breast cancer. Using the Western China Clinical Cooperation Group (WCCCG) database, we obtained the records of 7317 patients (with mammographic data) diagnosed with breast cancer between March 2011 and June 2016. These patients were divided into Groups I (mass alone) and II (mass combined with calcification), and their clinical and pathological data were compared. RESULTS: A total of 4211 patients were enrolled in Group I, and 3106 patients were enrolled in Group II. The tumors in Group II were more likely to be larger (P < 0.0001), higher grade (P = 0.0029), estrogen receptor (ER)+/progesterone receptor (PR)- (P = 0.0319), and human epidermal growth factor receptor 2 (HER-2)-positive (P < 0.0001), and to have axillary lymph node metastasis (P = 0.0033) than those in Group I. Regarding treatment, patients in Group II were more likely to have undergone chemotherapy (P = 0.0108) and anti-HER2 therapy (P = 0.0102), whereas patients in Group I were more likely to have undergone endocrine therapy (P < 0.0001). CONCLUSIONS: In conclusion, mammographic calcifications in tumors were associated with distinct clinicopathologic characteristics and aggressive treatments.

[Plasma Free mtDNA and Expression of TLR-9/MAPK in Brain Tissues of Rats with Subarachnoid Hemorrhage].

OBJECTIVES: To determine the plasma level of mitochondrial DNA (mtDNA) and the expression of Toll like receptor-9/mitogen-activated protein kinase (TLR-9/MAPK) in the brain tissues of rats with subarachnoid hemorrhage (SAH). METHODS: Sprague-Dawley rats were used to establish SAH models with a modified method of endovascular perforation. Twenty four hours after the establishment of the models, the plasma level of mtDNA in the rats was detected by real-time PCR; the expressions of TLR-9 and P38 MAPK in the brain tissues were detected by reverse transcription PCR (RT-PCR) and immunohistochemical staining. Differences between the SAH (n =20) and sham-surgical (n =20) groups were compared. RESULTS: Rats in the SAH group had higher levels of plasma mtNDA and expressions of TLR-9 and P38 MAPK in brain tissues than those in the sham-surgical group (P <0.05). CONCLUSION: Plasma free mtDNA and expressions of TLR-9/MAPK increase simultaneously in rats with SAH. mtDNA may induce system and local inflammation reactions in brain.

Molecular mechanism of ethylene stimulation of latex yield in rubber tree (Hevea brasiliensis) revealed by de novo sequencing and transcriptome analysis.

BACKGROUND: Rubber tree (Hevea brasiliensis) is an important industrial crop cultivated in tropical areas for natural rubber production. Treatment of the bark of rubber trees with ehephon (an ethylene releaser) has been a routine measure to increase latex yield, but the molecular mechanism behind the stimulation of rubber production by ethylene still remains a puzzle. Deciphering the enigma is of great importance for improvement of rubber tree for high yield. RESULTS: De novo sequencing and assembly of the bark transciptomes of Hevea brasiliensis induced with ethephon for 8 h (E8) and 24 h (E24) were performed. 51,965,770, 52,303,714 and 53,177,976 high-quality clean reads from E8, E24 and C (control) samples were assembled into 81,335, 80,048 and 80,800 unigenes respectively, with a total of 84,425 unigenes and an average length of 1,101 bp generated. 10,216 and 9,374 differentially expressed genes (DEGs) in E8 and E24 compared with C were respectively detected. The expression of several enzymes in crucial points of regulation in glycolysis were up-regulated and DEGs were not significantly enriched in isopentenyl diphosphate (IPP) biosynthesis pathway. In addition, up-regulated genes of great regulatory importance in carbon fixation (Calvin cycle) were identified. CONCLUSIONS: The rapid acceleration of glycolytic pathway supplying precursors for the biosynthesis of IPP and natural rubber, instead of rubber biosynthesis per se, may be responsible for ethylene stimulation of latex yield in rubber tree. The elevated rate of flux throughout the Calvin cycle may account for some durability of ethylene-induced stimulation. Our finding lays the foundations for molecular diagnostic and genetic engineering for high-yielding improvement of rubber tree.

Molecular cloning and expression analysis of an 1-aminocyclopropane-1-carboxylate synthase gene from Oncidium Gower Ramsey.

1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) is a rate-limiting enzyme in the biosynthesis of ethylene which regulates many aspects of the plant development and responses to biotic and abiotic stresses. In this study, a full-length cDNA of ACC synthase, OnACS2, was cloned from the senescing flower of Oncidium Gower Ramsey by RACE. The full-length cDNA of OnACS2 (GenBank accession no. JQ822087) was 1557 bp in length with an open reading frame (ORF) of 1308 bp encoding for a protein of 435 amino acid residues. The predicted OnACS2 protein had a molecular mass of 49.1 kDa with pI value of 7.51. Phylogenetic analysis indicated its evolutionary relationships with corresponding orthologous sequences in orchids, Hosta ventricosa and monocots. Real-time PCR assay demonstrated that OnACS2 was constitutively expressed in all tested organs with the highest transcript level in the gynandria. Differential expression pattern of OnACS2 gene correlated to the ethylene production and the subsequent occurrence of senescent symptoms in flower suggested that OnACS2 probably played an important role in the initiation of flower senescence.

Transcriptome sequencing and analysis of rubber tree (Hevea brasiliensis Muell.) to discover putative genes associated with tapping panel dryness (TPD).

BACKGROUND: Tapping panel dryness (TPD) involves in the partial or complete cessation of latex flow thus seriously affect latex production in rubber tree (Hevea brasiliensis). Numerous studies have been conducted to define its origin and nature, but the molecular nature and mechanism of TPD occurrence remains unknown. This study is committed to de novo sequencing and comparative analysis of the transcriptomes of healthy (H) and TPD-affected (T) rubber trees to identify the genes and pathways related to the TPD. RESULTS: Total raw reads of 34,632,012 and 35,913,020 bp were obtained from H and T library, respectively using Illumina Hiseq 2000 sequencing technology. De novo assemblies yielded 141,456 and 169,285 contigs, and 96,070 and 112,243 unigenes from H and T library, respectively. Among 73597 genes, 22577 genes were identified as differential expressed genes between H and T library via comparative transcript profiling. A majority of genes involved in natural rubber biosynthesis and jasmonate synthesis with most potential relevance in TPD occurrence were found to be differentially expressed. CONCLUSIONS: In TPD-affected trees, the expression of most genes related to the latex biosynthesis and jasmonate synthesis was severely inhibited and is probably the direct cause of the TPD. These new de novo transcriptome data sets provide a significant resource for the discovery of genes related to TPD and improve our understanding of the occurrence and maintainace of TPD.

Gain of function of mutant TP53 in glioblastoma: prognosis and response to temozolomide.

PURPOSE: Our aim was to investigate the relationship between mutant p53 and the prognosis of malignant glioma treated with temozolomide, and the regulation of mutant TP53 induced drug resistance, by molecular experimentation and a clinical trial. METHODS: Adult patients with newly surgical diagnosed glioblastoma were randomly assigned to receive either temozolomide or semustine after radiation treatment. The statuses of TP53 and expression of TP53 and O(6)-methylguanine DNA-methyltransferase (MGMT) were determined retrospectively in tumor tissue from enrolled patients. The primary end point was overall survival. Synthetic small interfering RNA was used to knock down mutant TP53 in T98G and U138 cells, which are human glioblastoma cells with a P53 mutation, by screening of exons 4-8. Viable cell survival was measured when these cells were exposed to temozolomide or semustine. Expression of MGMT at the messenger RNA level was also determined. RESULTS: The overall survival was 34.3 % at 2 years, 22.9 % at 3 years, 11.4 % at 4 years, and 8.6 % at 5 years with temozolomide, versus 18.2, 12.1, 3.0, and 0 %, respectively, with semustine. TP53 mutation and expression of mutant TP53 and MGMT showed significant inverse correlations with overall survival. Knockdown of mutant TP53 led to a fivefold increase in chemosensitivity to temozolomide but not semustine. Mutant TP53 knockdown induced down-regulation of MGMT expression. CONCLUSIONS: Mutant TP53 is strongly associated with a poor prognosis for overall survival in patients with glioblastoma. Also, TP53 mutation may decrease the chemosensitivity of glioblastoma to temozolomide by increasing MGMT expression.