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This paper presents the failure analysis of the crack and leakage accident of a crude oil pipeline under CO2-steam flooding in the western oilfield of China. To analyze the failure behavior and cause, different testing, including nondestructive testing, chemical composition analysis, tensile property testing, metallographic analysis, and microanalysis of fracture and chloride stress corrosion cracking (SCC) testing, are applied in the present study. The obtained results showed that the pipeline under the insulation layer of high humidity, high oxygen content, and high Cl− environment occurred pit corrosion, and the stress concentration area at the bottom of the corrosion pit sprouted cracks. Besides, it is demonstrated that the cracks were much branched, mostly through the crystal, and the fracture showed brittle, which is consistent with the typical characteristics of chloride SCC. Meanwhile, the insufficient Ni content of the pipeline material promoted the process of chloride SCC, and the high-temperature working conditions also aggravated the rate of chloride SCC. In addition, efficient precautions were provided to avoid fracture.

Objective. Motion analysis of surgical instruments can be used to evaluate laparoscopic surgical skills, and this study assessed the validity of an optical tracking system for the assessment of laparoscopic surgical motor skills. Methods. Ten experienced surgeons and ten novices were recruited to complete the transferring tasks on a laparoscopic simulator. An optical tracking system, Micron Tracker, was used to capture the marker points on each instrument and to obtain the coordinates of the marker points and the corresponding instrument tip coordinates. The data are processed to create a coordinate system based on the laparoscopic simulator and to calculate the movement parameters of the instruments, such as operating time, path length, speed, acceleration, and smoothness. At the same time, the range of motion of the instrument (insertion depth and pivoting angle) is also calculated. Results. The position that the tip of the instrument can reach is a small, irregularly shaped spatial area. Significant differences ( p < 0.05 ) were found between the surgeon and novice groups in parameters such as operating time, path length, mean speed, mean acceleration, and mean smoothness. The range of insertion depth of the instruments was approximately 150 mm to 240 mm, and the pivoting angles of the left and right instruments were 30.9° and 46.6° up and down and 28.0° and 35.0° left and right, respectively. Conclusions. The optical tracking system was effective in subjectively evaluating laparoscopic surgical skills, with significant differences between the surgeon and novice groups in terms of movement parameters, but not in terms of range of motion.

The mechanism of chemo-resistance in small cell lung cancer (SCLC) is unclear. This study aims to explore the resistance-related genomic profiles of residual tumors after neo-adjuvant chemotherapy (NAC) in SCLC through the whole-exome sequencing (WES).A total of 416 limited diseases (LD) SCLC patients underwent surgery were retrospectively analyzed, of which 40 patients received NAC. Then we selected 29 patients undergoing NAC (n = 19) and chemotherapy naïve (CTN, n = 10) to perform WES sequence with formalin-fixed paraffin-embedded samples including tumor and paired para-tumor.In total, single nucleotide variation and mutation rate were similar between NAC and CTN groups. The mutation signatures were significantly discrepant between NAC and CTN groups, as well as among patients with partial response (PR), stable disease (SD), and progressive disease. There were more copy number variation deletions in NAC group compared with CTN group. The inactivation of TP53 and RB1 were the most significantly events in both NAC and CTN groups. RB1 nonsense mutations were recurrent in NAC group (9/19 vs. 0/9, 47.4% vs. 0%) with favorable survival, while the frame-shift deletions were frequent in CTN group (3/9 vs. 3/19, 33.3% vs.15.8%). Integrated function enrichment revealed that the frequently mutant genes were involved in cell cycle, metabolic reprogramming, and oncogenic signaling pathways in NAC group, such as BTG2 pathway, glycolysis in senescence and P53 pathway. A total of 27 genes presented frequently mutant in NAC group and might played a positive role in drug resistance. Multiple genes including BRINP3, MYH6, ST18, and PCHD15, which were associated with prognosis, occurred mutant frequently in PR and SD groups.Residual tumors after neo-adjuvant therapy exhibited different mutation signature spectrum. Multiple genes including RB1 nonsense mutations, BRINP3, MYH6, ST18, and PCHD15 were with frequent mutation in residual tumors, which might participate chemo-resistance and influenced the prognosis in patients with limited disease SCLC.

We have developed a convenient chemical conversion method of preparing a Mg3(PO4)2 coating with a lamellar structure of about 1–5 μm width on Mg-Nd-Zn-Zr (denoted as JDBM) alloy, aiming to improve the corrosion resistance and biological response. The protective effect of the phosphate coating on JDBM alloy leads to an increase in corrosion resistance of about 25% from 0.337 ± 0.021 to 0.253 ± 0.047 mm y−1. A systematic study on in vitro cytocompatibility test shows that the phosphate coated JDBM has minimal negative effect on human umbilical vein endothelial cells (HUVECs) viability, growth and proliferation, and the coating also presents a favorable affinity for HUVECs by supporting higher adherent cell density and sufficient cell spreading. In addition, the investigation of in vitro hemocompatibility confirms reduced hemolysis ratio and excellent anti-platelet adhesion property of the phosphate coated JDBM. Furthermore, this study also presents our more recent efforts to develop an in-depth understanding of the mechanism which is involving anti-platelet adhesion on the surface of biodegradable Mg substrate.

Due to overlapping tremor features, the medical diagnosis of Parkinson’s disease (PD) and essential tremor (ET) mainly relies on the clinical experience of doctors, which often leads to misdiagnosis. Seven predictive models using machine learning algorithms including random forest (RF), eXtreme Gradient Boosting (XGBoost), support vector machine (SVM), logistic regression (LR), ridge classification (Ridge), backpropagation neural network (BP), and convolutional neural network (CNN) were evaluated and compared aiming to better differentiate between PD and ET by using accessible demographics and tremor information of the upper limbs. The tremor information including tremor acceleration and surface electromyogram (sEMG) signals were collected from 398 patients (PD = 257, ET = 141) and then were used to train the established models to separate PD and ET. The performance of the models was evaluated by indices of accuracy and area under the curve (AUC), which indicated the ensemble learning models including RF and XGBoost showed the best overall predictive ability with accuracy above 0.84 and AUC above 0.90. Furthermore, the relative importance of sex, age, four postures, and five tremor features was analyzed and ranked showing that the dominant frequency of sEMG of flexors, the average amplitude of sEMG of flexors, resting posture, and winging posture had a greater impact on the diagnosis of PD, whereas sex and age were less important. These results provide a reference for the intelligent diagnosis of PD and show promise for use in wearable tremor suppression devices.

Targeting DNA repair pathway offers an important therapeutic strategy for cancers. However, the failure of DNA repair inhibitors to markedly benefit patients necessitates the development of new strategies. Here, we show that exosome component 1 (EXOSC1) promotes DNA damages and sensitizes kidney renal clear cell carcinoma (KIRC) cells to DNA repair inhibitor. Considering that endogenous source of mutation (ESM) constantly assaults genomic DNA and likely sensitize cancer cells to the inhibitor, we first analyzed the statistical relationship between the expression of individual genes and the mutations for KIRC. Among the candidates, EXOSC1 most notably promoted DNA damages and subsequent mutations via preferentially cleaving C site(s) in single-stranded DNA. Consistently, EXOSC1 was more significantly correlated with C>A transversions in coding strands than these in template strands in KIRC. Notably, KIRC patients with high EXOSC1 showed a poor prognosis, and EXOSC1 sensitized cancer cells to poly(ADP-ribose) polymerase inhibitor. These results show that EXOSC1 acts as an ESM in KIRC, and targeting EXOSC1 might be a potential therapeutic strategy.

In this study, numerical simulation and physical experiments are carried out to investigate the influence of material surface microstructure on its hydrophobicity. By observing the contact angle and liquid phase state of the droplet on various morphological surfaces, the relationship between the size and morphology of microstructures and the hydrophobicity of material surface is explored. The influence of microstructure on the hydrophobicity is reflected by:1. changes of the contact angle along with the changes of microstructure size, 2. anisotropy of liquid droplet spreading along with the changes of wire groove and cylindrical morphology. Driven by tension, droplets can move spontaneously on the surface of specific microstructures, and the moving speed and direction vary with the distribution of the microstructures.

Purpose: A control algorithm for radio-frequency-induced intestinal tissue fusion was developed to explore the effects of different control parameters on intestinal tissue fusion. Materials and methods: Radio-frequency-induced fusion was performed on ex vivo small intestine tissue. The effect on the fusion was observed by changing the control parameters (power, interval time, and terminal impedance) in the algorithm. The quality of fusion was evaluated using the burst pressure and thermal damage measurement. Histological evaluation was used to assess the fusion quality indirectly. Results: A maximum burst pressure of 8.460 ± 0.2674 KPa was acquired when the power was set to 100 W, the interval time was set to 2000 ms, and the terminal impedance was set to 50 Ω. Moreover, the thermal damage range increased with an increase in power but decreased with an increase in the interval time and terminal impedance. Furthermore, the thermal damage range and temperature were presumably related. Conclusions: For an ex vivo small intestine tissue, the appropriate control parameters could be set when the power was approximately 100 W, the interval time was approximately 2000 ms, and the terminal impedance was approximately 50 Ω. This study could provide a basis for the selection of control parameters for intestinal tissue fusion.

Compressed natural gas (CNG) has been widely used as an automotive fuel in china, which the service security of CNG storage well (CSW), the main storage equipment in Chinese filling station, is becoming more and more prominent. In order to analyze the stress of CSW and its influencing factors, the mechanical model of CSW + cement sheath + stratum (CCS) processed by both elastic mechanics and finite element method was studied in this work. Using the most common well of Φ177.8× 10.36mm as a calculation case to obtain the analytic solutions and numerical solutions of CCS. The results indicated that the analytic solutions and numerical solutions are very close with relative deviation less than 3%, which verified their reliability each other. The calculation case can prove that the stress of CSW reduced evidently due to the effect of well cementation, which equivalent to the value of circular and axial stress of CSW strengthens to 18% and 20%. And when increasing the elastic modulus of cement sheath, the stress of CSW decreased that the support and potentiation to CSW by cement sheath becomes stronger.

Biodegradable magnesium (Mg) alloy emerges as revolutionary biomaterial by meeting both engineering and medical requirements for implants. In this study, we report a Mg alloy Mg-2.5Nd-0.21Zn-0.44Zr (wt. %, denoted as JDBM) potential for vascular stent application due to its outstanding performance in corrosion behaviors and biocompatibility. The investigation of corrosion properties evaluated by immersion test and electrochemical measurement shows less susceptibility to pitting corrosion and lower corrosion rate of JDBM as compared with AZ31 alloy. The corrosion products of JDBM do not cause significant adverse effect on the cell viability and growth during in vitro cytotoxicity test of the Mg extract via human vascular endothelial cells (HUVECs). We also investigated macrophage response to the Mg extract and observed compromised foreign body reaction (FBR) determined by human peripheral blood derived macrophage fusion and inflammatory cytokine and chemokine secretion. At last, we performed in vivo degradation assessment via implantation of JDBM stent in an animal model, and confirmed long-term stability and structural integrity of the stent in blood vessel. Thus, the JDBM alloy with excellent biocompatibility and long-term stability and durability in vivo, represents a significant advance in the development of biodegradable implants.

In recent years, fiber reinforced thermoplastic pipe (FRTP) has been widely used in oil fields of China due to its excellent corrosion resistance and coiling performance. With the further expansion of application scope, some failure accidents have occurred. Based on the inspection of the wall thickness, chemical composition and physical properties of a failed FRTP in the western oilfield of China, the causes are systematically analyzed. The results show that the main cause of the sample fracture is the decrease of the strength of FRTP due to the oil and gas media constantly penetrate into the lining and reinforced layer during the long-term service. Moreover, it is found that the outer sheath is worn and penetrated to the reinforced layer which further reduces the bearing pressure performance of FRTP and finally causes the fracture failure.

The administration of neoadjuvant chemotherapy (NAC) preceding radical cystectomy benefits overall survival for patients with muscle-invasive bladder cancer (MIBC). However, the relationship between the genetic profiling of MIBC and NAC response remains unclear. Here, a mutation panel of six cancer-associated genes (TSC1, FGFR3, TERT, TP53, PIK3CA and ERBB2) and an immunohistochemistry (IHC) panel containing eight bladder cancer (BC) biomarkers (EGFR, RRM1, PD-L1, BRCA1, TUBB3, ERCC, ERCC1, aberrantly glycosylated integrin α3β1 (AG) and CK5/6) were developed. BC samples from patients who showed a pathologic response (n = 39) and non-response (n = 13) were applied to the panel analysis. ERBB2, FGFR3 and PIK3CA exclusively altered in the responders group (19/39, 48.7%), in which FGFR3 mutations were significantly enriched in patients with a response in the cohort (14/39, 35.9%; P = 0.01). Additionally, strong expression of ERCC1 was associated with a pathologic response (P = 0.01). However, positive lymph node metastasis (P 0.01) and lymph-vascular invasion (LVI) (P = 0.03) were correlated with a non-response. Overall, the data show that FGFR3 mutations and elevated expression of ERCC1 in MIBCs are potential predictive biomarkers of the response to NAC.

Combined inhibition of BRAF and MEK1/2 (CIBM) improves therapeutic efficacy of BRAF-mutant melanoma. However, drug resistance to CIBM is inevitable and the drug resistance mechanisms still remain to be elucidated. Here, we show that BMK1 pathway contributes to the drug resistance to CIBM. Considering that ERK1/2 pathway regulates cellular processes by phosphorylating, we first performed a SILAC phosphoproteomic profiling of CIBM. Phosphorylation of 239 proteins was identified to be downregulated, while phosphorylation of 47 proteins was upregulated. Following siRNA screening of 47 upregulated proteins indicated that the knockdown of BMK1 showed the most significant ability to inhibit the proliferation of CIBM resistant cells. It was found that phosphorylation of BMK1 was enhanced in resistant cells, which suggested an association of BMK1 with drug resistance. Further study indicated that phospho-activation of BMK1 by MEK5D enhanced the resistance to CIBM. Conversely, inhibition of BMK1 by shRNAi or BMK1 inhibitor (XMD8-92) impaired not only the acquirement of resistance to CIBM, but also the proliferation of CIBM resistant cells. Further kinome-scale siRNA screening demonstrated that SRC\MEK5 cascade promotes the phospho-activation of BMK1 in response to CIBM. Our study not only provides a global phosphoproteomic view of CIBM in melanoma, but also demonstrates that inhibition of BMK1 has therapeutic potential for the treatment of melanoma.

We report a Mg alloy Mg-2.2Nd-0.1Zn-0.4Zr (wt.%, denoted as JDBM-2) showing great potential in clinical vascular stent application by integrating the advantages of traditional medical stainless steel and polymer. This alloy exhibits high yield strength and elongation of 276 ± 6 MPa and 34.3 ± 3.4% respectively. The JDBM-2 with a stable degradation surface results in a highly homogeneous degradation mechanism and long-term structural and mechanical durability. In vitro cytotoxicity test of the Mg extract via human vascular endothelial cells (HUVECs) indicates that the corrosion products are well tolerated by the tested cells and potentially negligible toxic effect on arterial vessel walls. This alloy also exhibits compromised foreign body response (FBR) determined by human peripheral blood derived macrophage adhesion, foreign body giant cell (FBGC) formation and inflammatory cytokine and chemokine secretion. Finally, vascular stents manufactured from the JDBM-2 were implanted into rabbits for long-term evaluation. The results confirm excellent tissue compatibility and up to 6-month structural and mechanical integrity of the stent in vivo. Thus, the JDBM-2 stent with up to 6-month structural and mechanical integrity and excellent tissue compatibility represents a major breakthrough in this field and a promising alternative to traditional medical stainless steel and polymer for the clinical application.

Endoscopic closure after endoscopic mucosal resection (EMR), endoscopic submucosal dissection (EMR) or endoscopic full-thickness resection (EFTR) is necessary to eliminate serious complications. Through-the-Scope clips are usually used in treating GI bleeding and perforation for their convenience and reliable outcome, but they are not ideal when the perforation size is larger than 2 cm since their opening width is limited. Several approaches are introduced to reinforce the performance of clips in regarding gathering edges of large defect by using endoloop and clips with double-channel endoscope [1]. Recently, an innovative endoscopic suturing technique using slipknot string and clips with single-channel endoscope has been reported, which resulted in shorter procedure time [2]. However, slipknot cannot maintain for a long time when exposing to distractions due to its poor holding strength. We have designed and fabricated an endoscopic clipping device and reported its initial ex-vivo results [3]. In this paper, a new suturing method is presented by using this device incorporated with a 4S-Modified Roeder (4SMR) knot, which enables such device to close large defect in a short time. Furthermore, the mechanical strength of 4SMR knot is also studied.

Late stent thrombosis (LST) following drug-eluting stent (DES) implantation in patients with coronary artery disease (CAD) is often associated with delayed vascular healing, resulting from vascular inflammation and hypersensitivity to durable polymers and drugs. Therefore, DES design, materials, and coatings have been technologically revolutionized. Herein, we designed a novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent (AGF-BP-SES), with a sirolimus content of only about one-third of traditional DES. The mechanical performances of AGF-BP-SES during compression and expansion were investigated. The pharmacokinetic (PK) profile of sirolimus was studied in the swine model. The in vivo efficacy of AGF-BP-SES was compared with that of Xience PRIME® stent. The results showed that AGF-BP-SES exhibited mechanical properties similar to traditional DES, including the rebound ratio of radial contraction/direction, rebound ratio of axial contraction/direction, and inhomogeneity of compression/expansion. Despite utilizing a reduced dose of sirolimus, AGF-BP-SES delivered sirolimus to the coronary artery in a controlled and efficient manner. The stent maintained a safe and effective local drug concentration without local or systemic risks. In the swine model, histopathological indicators predicted safety and biocompatibility of AGF-BP-SES. In conclusion, AGF-BP-SES maintained similar mechanical properties as other stents while reducing the drug-loading capacity, and showed a favorable safety and efficacy profile of the targeted DES.

Combined inhibition of BRAF and MEK1/2 (CIBM) improves therapeutic efficacy of BRAF-mutant melanoma. However, drug resistance to CIBM is inevitable and the drug resistance mechanisms still remain to be elucidated. Here, we show that BMK1 pathway contributes to the drug resistance to CIBM. Considering that ERK1/2 pathway regulates cellular processes by phosphorylating, we first performed a SILAC phosphoproteomic profiling of CIBM. Phosphorylation of 239 proteins was identified to be downregulated, while phosphorylation of 47 proteins was upregulated. Following siRNA screening of 47 upregulated proteins indicated that the knockdown of BMK1 showed the most significant ability to inhibit the proliferation of CIBM resistant cells. It was found that phosphorylation of BMK1 was enhanced in resistant cells, which suggested an association of BMK1 with drug resistance. Further study indicated that phospho-activation of BMK1 by MEK5D enhanced the resistance to CIBM. Conversely, inhibition of BMK1 by shRNAi or BMK1 inhibitor (XMD8-92) impaired not only the acquirement of resistance to CIBM, but also the proliferation of CIBM resistant cells. Further kinome-scale siRNA screening demonstrated that SRC\MEK5 cascade promotes the phospho-activation of BMK1 in response to CIBM. Our study not only provides a global phosphoproteomic view of CIBM in melanoma, but also demonstrates that inhibition of BMK1 has therapeutic potential for the treatment of melanoma.

An accurate detection of the effective values of electric voltage and current from high frequency power generators is a precondition for the development of smart electrotomes. In this light, an energy detection system based on personal computer (PC) is developed hereby. It senses voltage and current in isolation from generators with transformers, and then the measured values are amplified, filtered, transformed into single-ended signals and converted to RMS. The detected signals are transformed into digital signals through Data Acquisition Card (DAQ) and the data are processed with quadratic fit in Labview. Finally, the controller completes constant power output. The experiment results indicate that the energy detection system can measure the output parameters precisely and the controller can achieve constant power control.

Existing endoclip closure devices have difficulty in closing large colonic perforation. We developed a novel endoscopic multi-firing-clip applicator (EMFCA) system to address these limitations, and report on its initial evaluation.The functionality and efficacy of the prototype EMFCA equipped with re-openable clamp and preloaded with four clips were assessed using standardized 1.5 cm incisions created in ex-vivo porcine colonic segments. Endoscopic closure of the lacerations with two, three and four clips (n = five for each group) was followed by measurement of the leakage pressure of the three groups. Finite element analysis (FEA) was performed to validate the clip behavior and reliability during deployment.All 15 perforations were sealed without leakage until fully distended. The leakage pressures of colonic lacerations sealed with two, three, and four clips were 26.1 ± 2.8 mmHg, 37.3 ± 7.3 mmHg and 42.3 ± 7.4 mmHg, respectively. The mean operation time to deploy one clip was 25.4 ± 5.2 seconds. On FEA, the deformation of the shape of the clip matched that of the intended design, with each clip sustaining a maximum stress of 648.5 MPa without any material failure during deployment.These initial results confirm the efficacy of the EMFCA prototype system for endoscopic closure of colonic perforations.

Microsomal cytochrome b5 is a ubiquitous, 15.2 kDa haemoprotein implicated in a number of cellular processes such as fatty acid desaturation, drug metabolism, steroid hormone biosynthesis and methaemoglobin reduction. As a consequence of these functions this protein has been considered essential for life. Most of the ascribed functions of cytochrome b5, however, stem from in vitro studies and for this reason we have carried out a germline deletion of this enzyme. We have unexpectedly found that cytochrome b5 null mice were viable and fertile, with pups being born at expected Mendelian ratios. However, a number of intriguing phenotypes were identified, including altered drug metabolism, methaemoglobinemia and disrupted steroid hormone homeostasis. In addition to these previously identified roles for this protein, cytochrome b5 null mice displayed skin defects closely resembling those observed in autosomal recessive congenital ichthyosis and retardation of neonatal development, indicating that this protein, possibly as a consequence of its role in the de novo biosynthesis of unsaturated fatty acids, plays a central role in skin development and neonatal nutrition. Results from fatty acid profile analysis of several tissues suggest that cytochrome b5 plays a role controlling saturated/unsaturated homeostasis. These data demonstrate that regional concentrations of unsaturated fatty acids are controlled by endogenous metabolic pathways and not by diet alone. Electronic supplementary material The online version of this article (doi:10.1007/s11248-010-9426-1) contains supplementary material, which is available to authorized users.

// Chengli Song 1, * , Qiang Xu 1, * , Kui Jiang 1 , Guangyu Zhou 1 , Xuebin Yu 1 , Lina Wang 1 , Yuting Zhu 1 , Liping Fang 1 , Zhe Yu 1 , Jiing-Dwan Lee 2 , Shi-Cang Yu 3 , Qingkai Yang 1 1 Department of Oncology, The Second Affiliated Hospital of DaLian Medical University, Institute of Cancer Stem Cell, DaLian Medical University, Dalian, Liaoning 116044, China 2 Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA 3 Institute of Pathology and Southwest Cancer Center, Southwest Hospital, Third Military Medical University, Chongqing 400038, China * These authors have contributed equally to this work Correspondence to: Qingkai Yang, e-mail: Yangqingkai@dlmedu.edu.cn Shi-cang Yu, e-mail: Yushicang@163.com Keywords: cancer stem cell, BMK1, kinase Received: May 29, 2015 Accepted: September 17, 2015 Published: September 29, 2015 ABSTRACT Cancer stem cells (CSCs) possess many characteristics associated with stem cells and are believed to drive tumor initiation. Although targeting of CSCs offers great promise for the new generation of therapeutics, lack of the effective drugable target and appropriate pharmacological reagents significantly impedes the development of chemotherapies. Here, we show that the phosphorylation of BMK1 was significantly correlated with not only embryonic and induced pluripotent stem (iPS) cells, but also the CSCs. It was showed that activation of BMK1 by the expression of MEK5D enhanced the self-renew (sphere formation), proliferation (clone formation) and tumorigenic capacity of CSCs. While BMK1 inhibitor, XMD8-92, suppressed these capacities. RNA-seq and microarray analysis revealed that inhibition of BMK1 significantly enhanced the expression of BNIP3 and BNIP3L, which play important roles in cell death. Further study indicated that shRNA-mediated knock down of BNIP3 and BNIP3L impairs the BMK1 inhibitor, XMD8-92-induced suppression of sphere formation and clone formation of CSC. Collectively, these results not only indicate that BMK1 plays an important role in maintaining “stemness” of CSCs, but also implicate that BMK1 might be a potential drug target for CSCs.

Thermosensitive genic male-sterile (TGMS) lines, which are male-sterile at restrictive (high) temperatures but male-fertile at permissive (low) temperatures, have been widely used in breeding two-line hybrid rice (Oryza sativa L.). Here we find that mutation of thermosensitive genic male sterile 5 (tms5) in rice causes the TGMS trait through a loss of RNase Z(S1) function. We show that RNase Z(S1) processes the mRNAs of three ubiquitin fusion ribosomal protein L40 (UbL40) genes into multiple fragments in vitro and in vivo. In tms5 mutants, high temperature results in increased levels of UbL40 mRNAs. Overaccumulation of UbL40 mRNAs causes defective pollen production and male sterility. Our results uncover a novel mechanism of RNase Z(S1)-mediated UbL40 mRNA regulation and shows that loss of this regulation produces TGMS in rice, a finding with potential applications in hybrid crop breeding.

The wild species of the genus Oryza contain a largely untapped reservoir of agronomically important genes for rice improvement. Here we report the 261-Mb de novo assembled genome sequence of Oryza brachyantha. Low activity of long-terminal repeat retrotransposons and massive internal deletions of ancient long-terminal repeat elements lead to the compact genome of Oryza brachyantha. We model 32,038 protein-coding genes in the Oryza brachyantha genome, of which only 70% are located in collinear positions in comparison with the rice genome. Analysing breakpoints of non-collinear genes suggests that double-strand break repair through non-homologous end joining has an important role in gene movement and erosion of collinearity in the Oryza genomes. Transition of euchromatin to heterochromatin in the rice genome is accompanied by segmental and tandem duplications, further expanded by transposable element insertions. The high-quality reference genome sequence of Oryza brachyantha provides an important resource for functional and evolutionary studies in the genus Oryza., The wild rice species can be used as germplasm resources for this crop’s genetic improvement. Here Chen and colleagues report the de novo sequencing of the O. brachyantha genome, and identify the origin of genome size variation, the role of gene movement and its implications on heterochromatin evolution in the rice genome.

A fiber confocal backscattering FCBS spec- trometer is developed based on fiber confocal microscopy and light scattering theory. The FCBS spectrometer can provide imaging and spectral information simultaneously at the cellular scale. Normal stomach epithelial cell line GES-1 and cancerous cell line NCI-N87 are measured and their spectral results show that backscattering intensity from NCI-N87 cells is stronger than that from GES-1 cells in 500 to 800 nm, and the GES-1 cells scattering spectra show regular intensity changes, while the NCI-N87 cells do not. The experiments prove that the FCBS spectrometer is able to distinguish cancerous cells from normal stomach cells at the cellular level. The spectrometer could be fur- ther developed into a noninvasive optical technology for early cancer detection. © 2010 Society of Photo-Optical Instrumenta