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1.
Carbohydr Polym ; 240: 116334, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32475590

RESUMO

Chlorite is one of the representative iron-bearing silicates gangue minerals existed in the specularite ores which the traditional depressants are incapable of action in specularite/chlorite separation flotation. An attempt was conducted for the separation of specularite/chlorite with chitosan as a novel depressant through microflotation tests, Zeta potential measurements, adsorption tests, FT-IR, and XPS analysis. The microflotation results show that chitosan selectively depresses chlorite while specularite still keeps in high floatability. Zeta potential measurements and adsorption tests indicate that chitosan mainly adsorbed on chlorite surface, hindering the subsequent adsorption of dodecan-1-amine and leading the hydrophobicity distinction. The FT-IR spectra of chlorite validate the adsorption of chitosan on chlorite. The results of XPS illustrate that electrons partially transferred from chitosan to the aluminum, iron, magnesium, silicon, and adjacent oxygen atoms of silicon atoms in chlorite during the adsorption process.

2.
Cell Rep ; 31(6): 107621, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32402289

RESUMO

Follicular helper T cells (Tfhs) are essential for germinal center (GC) B cell maturation and antibody development. However, the intrinsic mechanisms that regulate Tfh differentiation are largely unknown. Here, we demonstrate that the frequencies of Tfhs and GC B cells, as well as interleukin-21 (IL-21) and anti-ovalbumin (OVA) antibodies, are markedly decreased in forkhead box O3 (Foxo3) knockout mice immunized with OVA. Using mixed bone marrow chimeras and lymphocyte-repopulated Rag1-/- mice proves that wild-type (WT), but not Foxo3-deficient T cells provoke GC B cell maturation and antibody production. Deficiency of Foxo3 inhibits inducible T cell co-stimulator (ICOS)-induced Tfh differentiation. Chromatin immunoprecipitation assay results suggest that Foxo3 is able to bind to the IL-21 promoter and regulate IL-21 secretion. In conclusion, our study unveils a critical role of Foxo3 in the regulation of Tfh differentiation and IL-21 production. Modulating Foxo3 activity may be beneficial for enhancing or preventing antibody-mediated immune responses.

3.
J Clin Invest ; 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32396532

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive cancers and is highly resistant to current treatments. ESCC harbors a subpopulation of cells exhibiting cancer stem-like cell (CSC) properties that contribute to therapeutic resistance including radioresistance, but the molecular mechanisms in ESCC CSCs are currently unknown. Here, we report that ribosomal S6 protein kinase 4 (RSK4) plays a pivotal role in promoting CSC properties and radioresistance in ESCC. RSK4 was highly expressed in ESCC CSCs and associated with radioresistance and poor survival in ESCC patients. RSK4 was found to be a direct downstream transcriptional target of ΔNp63α, the main p63 isoform, which is frequently amplified in ESCC. RSK4 activated the ß-catenin signaling pathway through direct phosphorylation of GSK-3ß Ser9. Pharmacologic inhibition of RSK4 effectively reduced CSC properties and improves radiosensitivity in both nude mice and patient-derived xenograft models. Collectively, our results strongly suggest that the ΔNp63α-RSK4-GSK-3ß axis plays a key role in driving CSC properties and radioresistance in ESCC, indicating that RSK4 is a promising therapeutic target for ESCC treatment.

4.
Hereditas ; 157(1): 20, 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32418541

RESUMO

BACKGROUND: Orchardgrass (Dactylis glomerata L.) is a popular cool-season perennial grass with a high production value, and orchardgrass seed is the fourth top-selling forage grass seed in the world. However, its yield and quality are often affected by flooding. To date, the molecular responses of orchardgrass to flooding were poorly understood. RESULTS: Here, we performed mRNA-seq to explore the transcriptomic responses of orchardgrass to a short term flooding (8 h and 24 h). There were 1454 and 565 differentially expressed genes identified in the 8 h and 24 h of flooding, respectively, compared to well control. GO functional enrichment analysis showed that oxidoreductase activity and oxidation-reduction process were highly present, suggesting that flooding induced the response to oxygen stress. Pathways enrichment analysis highlights the importance of glutathione metabolism, peroxidase, glycolysis and plant hormone signal transduction in response to flooding acclimation. Besides, the ROS clearance system is activated by significantly expressed glutathione S-transferase and genes encoding SOD and CAT (CAT1 and CDS2). The significant positive correlation between RNA sequencing data and a qPCR analysis indicated that the identified genes were credible. CONCLUSION: In the process of orchardgrass response to flooding stress, multiple differential genes and biological processes have participated in its acclimation to flooding, especially the biological processes involved in the removal of ROS. These results provide a basis for further research on the adaptation mechanism of orchardgrass to flood tolerance.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32468169

RESUMO

PURPOSE: Opioids are a mainstay for pain management after total joint arthroplasty (TJA). The prevalence and risk factors for prolonged opioid use after TJA are important to understand to help slow the opioid epidemic. We aim to summarize and evaluate the prevalence and time trend of prolonged opioid use after TJA and pool its risk factors. METHODS: Following the preferred reporting items for systematic reviews and meta-analysis statement, we systematically searched PubMed, the Cochrane Library, and EMBASE, etc. from inception up to October 1, 2019. Cohort studies reporting risk factors for prolonged opioids use (≥ 3 months) after TJA were included. Studies characteristics, risk ratios (RR), and prevalence of prolonged opioid use were extracted and synthesized. RESULTS: A total of 15 studies were published between 2015 and 2019, with 416,321 patients included. 12% [95%CI 10-14%] of patients had prolonged opioid use after TJA and its time trend was associated with median enrollment years (P = 0.0013). Previous opioid use (RR = 1.73; P < 0.001), post-traumatic stress disorder (RR = 1.34; P < 0.001), benzodiazepine use (RR = 1.38; P < 0.001), tobacco abuse (RR = 1.26; P < 0.001), fibromyalgia (RR = 1.51; P < 0.001), and back pain (RR = 1.34; P < 0.001) were the largest effective risk factors for prolonged use of opioids. CONCLUSIONS: To our knowledge, this is the first meta-analysis determining the risk factors of prolonged opioid use and characterizing its rate and time trend in TJA. Understanding risk factors for patients with higher potential for prolonged opioids use can be used to implement appropriate management strategies, reduce unsafe opioid prescriptions, and decrease the risk of prolonged opioid use after TJA.

6.
Neuroimage ; 215: 116838, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32298792

RESUMO

The human ventral visual cortex is functionally organized into different domains that sensitively respond to different categories, such as words and objects. There is heated debate over what principle constrains the locations of those domains. Taking the visual word form area (VWFA) as an example, we tested whether the word preference in this area originates from the bottom-up processes related to word shape (the shape hypothesis) or top-down connectivity of higher-order language regions (the connectivity hypothesis). We trained subjects to associate identical, meaningless, non-word-like figures with high-level features of either words or objects. We found that the word-feature learning for the figures elicited the neural activation change in the VWFA, and learning performance effectively predicted the activation strength of this area after learning. Word-learning effects were also observed in other language areas (i.e., the left posterior superior temporal gyrus, postcentral gyrus, and supplementary motor area), with increased functional connectivity between the VWFA and the language regions. In contrast, object-feature learning was not associated with obvious activation changes in the language regions. These results indicate that high-level language features of stimuli can modulate the activation of the VWFA, providing supportive evidence for the connectivity hypothesis of words processing in the ventral occipitotemporal cortex.

7.
Appl Microbiol Biotechnol ; 104(11): 5081-5094, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32274561

RESUMO

Deubiquitination is an essential regulatory step in the Ub-dependent pathway. Deubiquitinating enzymes (DUBs) mediate the removal of ubiquitin moieties from substrate proteins, which are involved in many regulatory mechanisms. As a component of the DUB module (Ubp8/Sgf11/Sus1/Sgf73) in the SAGA (Spt-Ada-Gcn5-acetyltransferase) complex, Ubp8 plays a crucial role in both Saccharomyces cerevisiae and humans. In S. cerevisiae, Ubp8-mediated deubiquitination regulates transcriptional activation processes. To investigate the contributions of Ubp8 to physiological and pathological development of filamentous fungi, we generated the deletion mutant of ortholog MoUBP8 (MGG-03527) in Magnaporthe oryzae (syn. Pyricularia oryzae). The ΔMoubp8 strain showed reduced sporulation, pathogenicity, and resistance to distinct stresses. Even though the conidia of the ΔMoubp8 mutant were delayed in appressorium formation, the normal and abnormal (none-septum or one-septum) conidia could finally form appressoria. Reduced melanin in the ΔMoubp8 mutant is highly responsible for the attenuated pathogenicity since the appressoria of the ΔMoubp8 mutant was much more fragile than those of the wild type, due to the defective turgidity. The weakened ability to detoxify or scavenge host-derived reactive oxygen species (ROS) further restricted the invasion of the pathogen. We also showed that carbon derepression, on the one hand, rendered the ΔMoubp8 strain highly sensitive to allyl alcohol, on the other hand, it enhances the resistance of the MoUBP8 defective strain to deoxyglucose. Overall, we suggest that MoUbp8 is not only required for sporulation, melanin formation, appressoria development, and pathogenicity but also involved in carbon catabolite repression of M. oryzae.

8.
Phytochemistry ; 175: 112378, 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32315838

RESUMO

Submergence is one of the environmental stresses that limit plant growth and development. Dactylis glomerata L. is an important cool-season forage grass globally. To investigate the genes related to submergence response and the molecular mechanism associated with submergence tolerance, the transcriptome of D. glomerata in response to waterlogging treatment was analyzed. RNA-sequencing was performed in two D. glomerata cultivars, submergence tolerant 'Dianbei' and submergence sensitive 'Anba'. A total of 50,045 unique genes matched the known proteins in the NCBI nr database by BLAST searches and 60.8% (30,418) of these genes were annotated with GO terms. Among these, 1395 genes only differentially expressed in 'Dianbei' and 18 genes shown different expression all the time were detected between the submergence tolerant 'Dianbei' and sensitive 'Anba'. Gene ontology (GO) and KEGG pathway enrichment analyses demonstrated that the DEGs were mainly implicated in oxidation-reduction system, nucleic acid binding transcription factor activity, and glycerol kinase activity. The D. glomerata assembled transcriptome provided substantial molecular resource for further genomic analysis of forage grasses in response to submergence stress. The significant difference in expression of specific unigenes may account for waterlogging tolerance or acclimation in the two different D. glomerata cultivars. This study provided new insights into the molecular basis of submergence tolerance in D. glomerata.

9.
ACS Nano ; 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32233458

RESUMO

Palladium diselenide (PdSe2), a peculiar noble metal dichalcogenide, has emerged as a new two-dimensional material with high predicted carrier mobility and a widely tunable band gap for device applications. The inherent in-plane anisotropy endowed by the pentagonal structure further renders PdSe2 promising for novel electronic, photonic, and thermoelectric applications. However, the direct synthesis of few-layer PdSe2 is still challenging and rarely reported. Here, we demonstrate that few-layer, single-crystal PdSe2 flakes can be synthesized at a relatively low growth temperature (300 °C) on sapphire substrates using low-pressure chemical vapor deposition (CVD). The well-defined rectangular domain shape and precisely determined layer number of the CVD-grown PdSe2 enable us to investigate their layer-dependent and in-plane anisotropic properties. The experimentally determined layer-dependent band gap shrinkage combined with first-principle calculations suggest that the interlayer interaction is weaker in few-layer PdSe2 in comparison with that in bulk crystals. Field-effect transistors based on the CVD-grown PdSe2 also show performances comparable to those based on exfoliated samples. The low-temperature synthesis method reported here provides a feasible approach to fabricate high-quality few-layer PdSe2 for device applications.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32306092

RESUMO

BACKGROUND: Unsatisfactory alignment in unicompartmental knee arthroplasty (UKA) is one potential cause of postoperative failure. Patient-specific instruments (PSIs) are designed to improve the alignment of the prostheses, but the effect of PSIs on the alignment or clinical outcome is controversial and lacks validated evidence. We conducted a meta-analysis and systematic review to determine the effect of PSIs on UKA outcomes for the first time. MATERIALS AND METHODS: A systematic literature search in MEDLINE, EMBASE, CNKI (Chinese database) and Cochrane Central Register of Controlled Trials (up to June 2019) was performed to collect studies that compared PSIs with conventional instruments. Two reviewers independently screened all the records on the basis of inclusion and exclusion criteria. Quality assessments with Cochrane's quality assessment tool or Newcastle-Ottawa scale (NOS) were conducted, the data were extracted, and statistical analyses were completed. RESULTS: Ten studies with 444 knees were included. The meta-analysis confirmed that PSIs contributed to reduced errors in the alignment of the femoral compartment in the sagittal plane (mean difference = - 2.53, CI [- 3.14, - 1.99], P < 0.01) and the tibial compartment in both the coronal (mean difference = - 0.97, CI [- 1.44, - 0.49], P < 0.01) and the sagittal plane (mean difference = - 1.29, CI [- 1.81, - 0.76], P < 0.01). One study supported that PSIs reduced outliers in inexperienced surgeons; however, all studies investigating PSIs among experienced surgeons suggested that PSIs cannot reduce the percentage of outliers. There was no significant difference in the postoperative score (mean difference = - 0.06, CI [- 0.36, 0.23], P = 0.68) or rate of complications (RR = 1.02, CI [0.15, 6.79], P = 0.99) between PSIs and conventional instruments. CONCLUSION: The findings of this study suggest PSIs could not reduce the percentage of outliers in UKA patients for experts, and postoperative scores and complication rates are not improved by PSIs, compared with conventional instruments. Based on this meta-analysis and systematic review, no practical benefit to UKAs in experts was detected in PSIs. The findings of this study also suggest that PSIs improved alignment of UKA and might be beneficial to inexperienced surgeons, but it is still unclear whether this improvement is clinically significant and the evidence of inexperienced surgeons is limited. Therefore, more high-quality RCTs are need to be carried out in the future.

11.
Pathol Res Pract ; : 152954, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32321658

RESUMO

BACKGROUND: MAGE family genes have been studied as targets for tumor immunotherapy for a long time. Here, we combined MAGE1-, MAGE3- and MAGEn-derived peptides as a cancer vaccine and tested whether a new combination nanoemulsion-encapsulated vaccine could be used to inhibit the growth of tumor cells in humanized SCID mice. METHODS: The nanoemulsion-encapsulated complex protein vaccine (MAGE1, MAGE3, and MAGEn/HSP70 fusion protein; M1M3MnH) was prepared using a magnetic ultrasonic technique. After screening, human PBMCs were injected into SCID mice to mimic the human immune system. Then, the humanized SCID mice were challenged with M3-HHCC cells and immunized with nanoemulsion-encapsulated MAGE1-MAGE3-MAGEn/HSP70 [NE(M1M3MnH)] or M1M3MnH. The cellular immune responses were detected by IFN-γ ELISPOT and cytotoxicity assays. Therapeutic and tumor challenge experiments were also performed. RESULTS: The results showed that the immune responses elicited by NE(M1M3MnH) were apparently stronger than those elicited by M1M3MnH, NE(-) or PBS, suggesting that this novel nanoemulsion carrier induces potent antitumor immunity against the encapsulated antigens. The results of the therapeutic and tumor challenge experiments also indicated that the new vaccine had a definite effect on SCID mice bearing human hepatic cancer. CONCLUSION: Our study indicated that the combination of several tumor antigen-derived peptides may be a relatively good strategy for peptide-based cancer immunotherapy. These results suggest that the complex nanoemulsion vaccine could have broader applications for both therapy and prevention mediated by antitumor effects in the future.

12.
Oncogene ; 39(20): 3980-3996, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32238881

RESUMO

Branched-chain α-keto acid dehydrogenase kinase (BCKDK), the key enzyme of branched-chain amino acids (BCAAs) metabolism, has been reported to promote colorectal cancer (CRC) tumorigenesis by upregulating the MEK-ERK signaling pathway. However, the profile of BCKDK in metastatic colorectal cancer (mCRC) remains unknown. Here, we report a novel role of BCKDK in mCRC. BCKDK is upregulated in CRC tissues. Increased BCKDK expression was associated with metastasis and poor clinical prognosis in CRC patients. Knockdown of BCKDK decreased CRC cell migration and invasion ex vivo, and lung metastasis in vivo. BCKDK promoted the epithelial mesenchymal transition (EMT) program, by decreasing the expression of E-cadherin, epithelial marker, and increasing the expression of N-cadherin and Vimentin, which are mesenchymal markers. Moreover, BCKDK-knockdown experiments in combination with phosphoproteomics analysis revealed the potent role of BCKDK in modulating multiple signal transduction pathways, including EMT and metastasis. Src phosphorylated BCKDK at the tyrosine 246 (Y246) site in vitro and ex vivo. Knockdown and knockout of Src downregulated the phosphorylation of BCKDK. Importantly, phosphorylation of BCKDK by Src enhanced the activity and stability of BCKDK, thereby promoting the migration, invasion, and EMT of CRC cells. In summary, the identification of BCKDK as a novel prometastatic factor in human CRC will be beneficial for further diagnostic biomarker studies and suggests novel targeting opportunities.

13.
Int J Biol Macromol ; 157: 401-413, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32339590

RESUMO

In this study, a novel thiourea grafted porous sodium alginate-based adsorbent was synthesized by combining ion-imprinting and direct templating method. Due to ion-imprinting, the prepared adsorbent has demonstrated outstanding selectivity towards Pd (II) from bi-metallic solution at different pH values. Langmuir and both pseudo-first and pseudo-second kinetic equations were used to describe the adsorption isotherm and kinetics, respectively. FT-IR, XPS, and SEM-EDX analyses suggested that selective adsorption of Pd (II) was dominated by electrostatic interactions at pH 1.0 and chelation on imprinted sorption sites at pH 3.0. Density functional theory (DFT) calculation further explained the effect of ion-imprinting and provided two binding configurations, which is consistent with characterization analyses. The pregnant adsorbent can be regenerated and reused by thiourea solution in dilute hydrochloric acid. Therefore, the synthesized adsorbent would be useful as a selective adsorbent for the enrichment of Pd (II) from effluents.

14.
Nanotechnology ; 31(27): 275204, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32208372

RESUMO

A new flexible memory element is crucial for mobile and wearable electronics. A new concept for memory operation and innovative device structure with new materials is certainly required to address the bottleneck of memory applications now and in the future. We report a new nonvolatile molecular memory with a new operating mechanism based on two-dimensional (2D) material nanochannel field-effect transistors (FETs). The smallest channel length for our 2D material nanochannel FETs was approximately 30 nm. The modified molecular configuration for charge induced in the nanochannel of the MoS2 FET can be tuned by applying an up-gate voltage pulse, which can vary the channel conductance to exhibit memory states. Through controlling the amounts of triggered molecules through either different gate voltage pulses or gate duration time, multilevel states were obtained in the molecular memory. These new molecular memory transistors exhibited an erase/program ratio of more than three orders of current magnitude and high sensitivity, of a few picoamperes, at the current level. Reproducible operation and four-level states with stable retention and endurance were achieved. We believe this prototype device has potential for use in future memory devices.

15.
Diagn Pathol ; 15(1): 28, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209138

RESUMO

BACKGROUND: To investigate the expression and function of RSK4, MMP-9 and CD44 in primary clear cell renal cell carcinoma (primary ccRCC) and metastatic clear cell renal cell carcinoma (metastatic ccRCC), as well as the correlation with clinicopathological features of patients. METHOD: The expression levels of RSK4, CD44 and MMP-9 in 52 primary ccRCC samples and 48 metastatic ccRCC samples were detected by immunohistochemistry, and the relationship between RSK4, CD44 and MMP-9 expression and clinicopathological features as well as prognosis of metastatic ccRCC patients was statistically analysed. Ectopic RSK4 expression in ccRCC cell lines was performed to determine its effect on cell cycle regulation, tumour invasiveness, and metastatic capability. RESULTS: The positive rates of RSK4, MMP-9 and CD44 expression in metastatic ccRCC tissues were 75, 68.75 and 91.7%, respectively, while the rates in primary ccRCC tissues were 44.2, 34.6 and 69.2%, respectively. Thus, the positive rates in metastatic ccRCC were higher than those in primary ccRCC (PRSK4 = 0. 002; PMMP-9 = 0. 002; PCD44 = 0. 001). However, the expression of RSK4, CD44 and MMP-9 was unrelated to age, gender, or metastatic sites (P > 0.05) but was related to WHO/ISUP nucleolar grade (PRSK4 = 0.019; PCD44 = 0.026; PMMP-9 = 0.049). In metastatic ccRCC, expression among the three proteins showed a positive correlation (P = 0.008). Moreover, expression between RSK4 and CD44 (P = 0.019) and MMP-9 and CD44 (P = 0.05) also showed positive correlations, whereas RSK4 and MMP-9 showed no significant correlation (P = 1.00). Molecular studies showed that overexpression of RSK4 could enhance the invasive and migratory abilities of ccRCC cell lines through the regulation of CD44 and MMP-9 expression and vice versa. CONCLUSIONS: The overexpression of RSK4, MMP-9 and CD44 is associated with the invasion and metastasis of ccRCC, indicating that they could be potential prognostic factors and serve as new potential therapeutic targets for ccRCC.

16.
J Phys Chem Lett ; 11(8): 2788-2796, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32191475

RESUMO

Narrow-spectrum antimicrobials specifically eradicate the target pathogens but suffer from significantly lagging development. Photodynamic therapy eliminates cells with reactive oxygen species (ROS) generated upon light irradiation but is intrinsically a wide-spectrum modality. We herein converted photodynamic therapy into a narrow-spectrum modality by taking advantage of a previously unnoticed physics recognition pathway. We found that negatively charged nanospheres undergo selective entropy gain-driven adsorption onto spherical bacteria, but not onto rod-like bacteria. This bacterial morphology-targeting selectivity, combined with the extremely limited effective radii of action of ROS, enabled photodynamic nanospheres to kill >99% of inoculated spherical bacteria upon light irradiation and <1% of rod-like bacteria under comparable conditions, indicative of narrow-spectrum activity against spherical bacteria. This work unveils the bacterial morphology selectivity in the adsorption of negatively charged nanospheres and suggests a new approach for treating infections characterized by overthriving spherical bacteria in niches naturally dominated by rod-like bacteria.

17.
Rice (N Y) ; 13(1): 19, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170462

RESUMO

BACKGROUND: Rice blast is generally considered the most devastating rice disease worldwide. The development of resistant varieties has been proven to be the most economical strategy to control the disease. A cluster of resistant (R) genes on rice chromosome 12 including Pita, Pita2 and Ptr has been studies for decades. However, the relationship between these R genes has not been well established. RESULTS: In this study, we compared the resistance spectra controlled by Pita2 and Pita by testing their monogenic lines (MLs) in four hotspots found in the Philippines and Burundi from 2014 to 2018. The reaction patterns were distinct in two countries and that Pita2-mediated field resistance was relatively prevalent. Pathogenicity tests using 328 single-spore isolates in greenhouse further verified that IRBLta2-Re for Pita2 conferred a relatively broader spectrum resistance than those of Pita. Rough and fine mapping of Pita2 were conducted using F2 and F3 populations derived from IRBLta2-Re [CO] and CO 39 consisting of 4344 progeny to delimit Pita2 in a genomic interval flanked by two markers 12 g18530 and 12 g18920 proximal to the centromere of chromosome 12. Alignment of the markers to the genomic sequence of IR64, which harbors Pita2 verified by genetic analysis, approximately delimited the candidate gene(s) within 313-kb genomic fragment. The two Pita2 suppressive mutants that contain mutations within Pita2 were verified and identified. Comparative sequence analysis in these two mutants further identified that each individual allele contains a single nucleotide substitution at a different position resulting in nonsense and missense mutations in the protein product of LOC_Os12g18729. On the contrary, no sequence mutation was detected in other candidate genes, indicating that mutations in LOC_Os12g18729 were responsible for the loss of function of Pita2. Pita2 encodes a novel R protein unique from Pita, which is exactly identical to the previously cloned Ptr. Moreover, based on the resistance gene analysis of rice varieties and mutants containing Pita, it was found that Pita2 rather than Pita was responsible for the specificity to some differential isolates with AvrPita. The diagnosis and survey of Pita2 in IRRI released varieties showed relatively low frequency, implying a high value of its application for breeding resistant varieties against rice blast via marker assisted selection. CONCLUSION: Our study clarified the relationship between Pita, Pita2 and Ptr. Pita2 is identical to Ptr and distinct from Pita in both sequence and chromosomal location although Pita2 and Pita are genetically linked to each other. The loss of function of Pita2 but not Pita eliminate the specificity to some AvrPita containing isolates, however, the mechanism underlying the recognition between Pita2/Pita and AvrPita remains elusive.

18.
Clin Chem Lab Med ; 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32146438

RESUMO

Background Evidence-based evaluation of laboratory performances including pre-analytical, analytical and post-analytical stages of the total testing process (TTP) is crucial to ensure patients receiving safe, efficient and effective care. To conduct risk assessment, quality management tools such as Failure Mode and Effect Analysis (FMEA) and the Failure Reporting and Corrective Action System (FRACAS) were constantly used for proactive or reactive analysis, respectively. However, FMEA and FRACAS faced big challenges in determining the scoring scales and failure prioritization in the assessment of real-world cases. Here, we developed a novel strategy, by incorporating Sigma metrics into risk assessment based on quality indicators (QIs) data, to provide a more objective assessment of risks in TTP. Methods QI data was collected for 1 year and FRACAS was applied to produce the risk rating based on three variables: (1) Sigma metrics for the frequency of defects; (2) possible consequence; (3) detection method. The risk priority number (RPN) of each QI was calculated by a 5-point scale score, where a value of RPN > 50 was rated as high-risk. Results The RPNs of two QIs in post-analytical phase (TAT of Stat biochemistry analyte and Timely critical values notification) were above 50 which required rigorous monitoring and corrective actions to eliminate the high risks. Nine QIs (RPNs between 25 and 50) required further investigation and monitoring. After 3 months of corrective action the two identified high-risk processes were successfully reduced. Conclusions The strategy can be implemented to reduce identified risk and assuring patient safety.

20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(3): 362-366, 2020 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-32174084

RESUMO

Objective: To study the expressions of Renin, angiotensin converting enzyme (ACE), angiotensin receptor 1 (AT1R), and AT2R in synovial tissue of osteoarthritis (OA) at different stages. Methods: The patients who were treated with upper knee amputation because of trauma or total knee arthroplasty for OA between January 2018 and December 2018 were enrolled. Among them, 32 patients who met the selection criteria were included in the study. According to the Kellgren-Lawrence (K-L) X-ray classification, they were allocated to normal synovial group (group A, n=9), moderate OA synovial group (group B, n=11, K-L level 3), and advanced OA synovial group (group C, n=12, K-L level 4). The relative expressions of Renin, ACE, AT1R, and AT2R mRNAs and proteins were detected by real-time fluorescence quantitative PCR (qRT-PCR) and Western blot. Results: The relative expressions of Renin, ACE, and AT1R mRNAs and proteins were significantly higher in group B and group C than in group A ( P<0.05). The relative expressions of ACE and AT1R mRNAs and proteins and Renin protein were significantly higher in group C than in group B ( P<0.05). However, the relative expressions of AT2R mRNA and protein were lower in group B and group C than in group A ( P<0.05), and in group C than in group B ( P<0.05). Conclusion: The expressions of Renin, ACE, and AT1R in synovial tissue of osteoarthritis significantly increase as the K-L level increased, and the expression of AT2R decreases. Renin, ACE, AT1R, and AT2R have a certain degree of correlation with the development of OA.

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