The Scheduling Mode of Anesthesia Nurses Affects Postanesthesia Care Unit Efficiency: A Single-Center Retrospective Study From China.

PURPOSE: Anesthesia nurses play an important postsurgical role during the anesthesia recovery period, which is characterized by a high incidence of complications related to anesthesia and surgery. Strengthening staff allocation and skill management in the postanesthesia care unit (PACU) is therefore particularly important in managing length of stay. We aimed to investigate the effect of two schedule modes for anesthesia nurses on PACU efficiency. DESIGN: A retrospective observational cohort study. METHODS: We conducted a retrospective study in a large tertiary academic medical center. In 2018, the PACU operated with traditional scheduling and the nurse-to-patient ratio was 1.2:1. The PACU implemented intensive scheduling and this ratio was adjusted to 1:1 in 2019 by adjusting the anesthesia nurse allocation scheme. We compared the number of admitted patients, length of PACU stay, the incidence of anesthesia-related complications, and nurse satisfaction with the two modes. FINDINGS: The total number of admitted patients was 10,531 in 2018 and 10,914 in 2019. PACU admitted 401 more patients in 2019 than in 2018, even with two fewer nurses per day. Nevertheless, the median length of PACU stay in 2019 was statistically significantly shorter than in 2018 (29 [22-40] vs 28 [21-39], P < .001], while the incidence of anesthesia-related complications including postoperative pain, nausea and vomiting, hypertension, and shivering were comparable in the 2 years (P > .091). The intensive scheduling implemented in 2019 received more satisfaction from nurses than the traditional scheduling applied in 2018 (P < .01). CONCLUSIONS: The scheduling of anesthesia nurses affects PACU efficiency. The intensive scheduling mode implemented in 2019 resulted in a comparable number of admitted patients, a better quality of care, and higher nurse satisfaction than those under the traditional scheduling mode.

Graph Theory Further Revealed Visual Spatial Working Memory Impairment in Patients with Inflammatory Bowel Disease.

Background: Inflammatory Bowel Disease (IBD) patients may experience cognitive impairments in Visuospatial Working Memory (VSWM), significantly impacting their quality of life. However, the mechanisms underlying these impairments remain poorly understood. Methods: We studied functional MRI and graph theory analysis to investigate changes in functional connectivity networks during the Mental Rotation Task (MRT) in IBD patients. Twenty IBD patients (13 males, 7 females; mean age = 34.95 ± 13.80 years; mean disease duration = 2.43 ± 2.37 years) participated in the study. Exclusion criteria encompassed recent use of analgesics, 5-Aminosalicylate, corticosteroids, or immunosuppressants within the past three months. Additionally, we recruited 20 age-, gender-, and education-matched healthy controls for comparison. Results: Compared to a control group, IBD patients exhibited significantly longer reaction times and reduced accuracy during the MRT. Our analysis revealed abnormalities in multiple nodal attributes within the functional connectivity network, particularly in regions such as the bilateral orbitofrontal cortex, right supplementary motor area, bilateral parahippocampal gyrus, and bilateral anterior temporal lobe. We observed that the nodal efficiency in the left temporal pole is negatively correlated with Red Blood Cell Distribution Width (RDW) and positively correlated with response time of MRT. Conclusion: Our findings revealed notable abnormalities in multiple node attributes among IBD patients during MRT, providing evidence of cognitive impairments in VSWM in IBD patients. This study found RDW maybe can serve as a clinical indicator for predicting early VSWM impairment in patients with IBD.

Pretreatment with long-acting gonadotropin-releasing hormone agonists improved pregnancy outcomes after hysteroscopic multiple polypectomies: A retrospective study of 660 frozen-thawed embryo transfer cycles.

OBJECTIVE: To compare the reproductive pregnancy outcomes of pretreatment with long-acting gonadotropin-releasing hormone agonist (GnRH-a) plus hormone replacement therapy (HRT) with HRT-only cycles, and investigate differences between single polypectomy and multiple polypectomies, and between one or two doses of GnRH-a. MATERIALS AND METHODS: This was a retrospective cohort study on patients undergoing polypectomy who underwent frozen-thawed embryo transfer (FET) from March 2018 to May 2019. They were divided into GnRH-a pretreatment and HRT-only groups. Each group was divided into single polypectomy or multiple polypectomies (in a single hysteroscopic session) subgroups. Clinical pregnancy rate and live birth rate (LBR) were the main outcomes. The effect of GnRH-a dosage was further analysed. RESULTS: There were 212 GnRH-a pretreatment cases (45 single and 167 multiple polyps) and 448 HRT-only cases (228 single and 220 multiple polyps). The LBR of the GnRH-a pretreatment group (53.3%) was significantly higher than the HRT group (43.3%; P = 0.016). Logistic regression analysis showed that GnRH-a pretreatment significantly affected the LBR (odds ratio, OR 1.470, 95% confidence interval, Cl 1.046-2.065; P = 0.026). In the multiple polypectomy subgroup, the LBR with GnRH-a pretreatment was higher than with HRT-only (54.5% vs 43.6%; P = 0.034). However, the LBR was not different between the respective single polypectomy subgroups (48.9% vs 43.0%; P = 0.466). For patients with multiple polyps, two GnRH-a pretreatments produced a higher LBR than a single GnRH-a pretreatment (62.7% vs 47.8%), but without significant difference (P = 0.055). CONCLUSION: GnRH-a pretreatment improved the LBR for FET cycles after hysteroscopic multiple polypectomies, independent of dose.

Granulocyte-macrophage colony-stimulating factor promotes endometrial repair after injury by regulating macrophages in mice.

Intrauterine adhesion (IUA) caused by endometrial injury is a common cause of female infertility and is challenging to treat. Macrophages play a critical role in tissue repair and cyclical endometrial regeneration. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has significant reparative and anti-fibrotic effects in various tissues. However, there is limited research on the role of GM-CSF in the repair of endometrial injury and the involvement of macrophages in GM-CSF-mediated endometrial repair. In this study, using a mouse model of endometrial scratching injury, we found that GM-CSF treatment accelerated the repair of endometrial injury and improved fertility. At the molecular level, we observed that GM-CSF can downregulate the transcript levels of tumor necrosis factor (TNF) in mouse bone marrow-derived macrophages (BMDMs) stimulated by lipopolysaccharide (LPS) and upregulate the expression of Arginase-1 (Arg-1) and mannose receptor C-type 1 (MRC1). Importantly, during the early and middle stages of injury, GM-CSF increased the proportion of M1-like, M2-like, and M1/M2 mixed macrophages, while in the late stage of injury, GM-CSF facilitated a decline in the number of M2-like macrophages. These findings suggest that GM-CSF may promote endometrial repair by recruiting macrophages and modulating the LPS-induced M1-like macrophages into a less inflammatory phenotype. These insights have the potential to contribute to the development of novel therapeutic approaches for the treatment of intrauterine adhesion and related infertility.

MicroRNA-122-5p alleviates endometrial fibrosis via inhibiting the TGF-ß/SMAD pathway in Asherman's syndrome.

RESEARCH QUESTION: What is the effect of miR-122 on the progression and recovery of fibrosis in Asherman's syndrome? DESIGN: Endometrial tissue was collected from 21 patients, 11 with intrauterine adhesion (IUA) and 10 without IUA. Quantitative real-time polymerase chain reaction, immunofluorescence and Western blot were applied to observe the expression of mRNAs/miRNAs and protein, respectively. The endometrial physical injury was carried out in C57BL/6 mice to create an endometrial fibrosis model, with intrauterine injection of adenovirus to compare the antifibrosis and repair function of miR-122 on endometrium. The morphology of the uterus was observed using haematoxylin and eosin staining, and fibrosis markers were detected by immunohistochemistry. RESULTS: miR-122 expression was reduced in patients with IUAs, accompanied by fibrosis. MiR-122 overexpression reduced the degree of fibrosis in endometrial stromal cells. Further molecular analyses demonstrated that miR-122 inhibited fibrosis through the TGF-ß/SMAD pathway by directly targeting the 3' untranslated region of SMAD family member 3, suppressing its expression. Notably, miR-122 promoted endometrial regeneration and recovery of pregnancy capacity in a mouse endometrial injury model. CONCLUSIONS: miR-122 is a critical regulator for repair of endometrial fibrosis and provided new insight for the clinical treatment of intrauterine adhesions.

A Self-Assembled G-Quadruplex/Hemin DNAzyme-Driven DNA Walker Strategy for Sensitive and Rapid Detection of Lead Ions Based on Rolling Circle Amplification.

Herein, a sensitive biosensor is constructed based on a novel rolling circle amplification (RCA) for colorimetric quantification of lead ion (Pb2+). At the detection system, GR5 DNAzymes are modified on the surface of an immunomagnetic bead, and Pb2+ is captured by the aptamer, inducing the disintegration of the GR5 DNAzyme and the release of the DNA walker. After the introduction of the template DNA, T4 DNA ligase, and phi29 DNA polymerase, an RCA is initiated for the sensitivity improvement of this method. Moreover, a G4-hemin DNAzyme is formed as a colorimetric signal, owing to its peroxide-like activity to catalyze the TMB-H2O2 substrate. Under the optimized conditions, the limit of detection (LOD) of this fabricated biosensor could reach 3.3 pM for Pb2+ with a concentration in the range of 0.01-1000 nM. Furthermore, the results of real samples analysis demonstrate its satisfactory accuracy, implying its great potential in the rapid detection of heavy metals in the environment.

KRT18 regulates trophoblast cell migration and invasion which are essential for embryo implantation.

Female infertility is a worldwide concern that impacts the quality of life and well-being of affected couples. Failure of embryo implantation is a major cause of early pregnancy loss and is precisely regulated by a programmed molecular mechanism. Recent studies have shown that proper trophoblast adhesion and invasion are essential for embryo implantation. However, the potential regulatory mechanism involved in trophoblast adhesion and invasion has yet to be fully elucidated. KRT18 has been reported to play a critical role in early embryonic development, but its physiological function in embryo implantation remains unclear. In the present study, we revealed that KRT18 was highly expressed in trophoblast cells and that knockdown of KRT18 in mouse embryos inhibited embryo adhesion and implantation. In vitro experiments further showed that silencing KRT18 disturbed trophoblast migration and invasion. More importantly, we provide evidence that KRT18 directly binds to and stabilizes cell surface E-cadherin in trophoblast cells through microscale thermophoresis (MST) analysis and molecular biology experiments. In brief, our data reveal that KRT18, which is highly expressed in trophoblast cells, plays an important role in the regulation of trophoblast invasion and adhesion during embryo implantation by directly binding to E-cadherin.

Effects of bisphenols on lipid metabolism and neuro-cardiovascular toxicity in marine medaka larvae.

Bisphenols are environmental endocrine disruptors that have detrimental effects on aquatic organisms. Using marine medaka larvae, this study explored the effects of bisphenol compounds [bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF)] on the early growth and development of aquatic organisms. Marine medaka larvae were exposed to bisphenol compounds at concentrations of 0.05, 0.5, and 5 µM for 72 h, and changes in heartbeat rate, behavior, hormone levels, and gene expression were determined. Bisphenols were shown to have a toxic effect on the cardiovascular system of larvae and can cause neurotoxicity and endocrine disruption, such as changes to thyroid-related hormones. Functional enrichment showed that bisphenols mainly affect lipid metabolism and cardiac muscle contraction of larvae, which implied that the main toxic effects of bisphenols on marine medaka larvae targeted the liver and heart. This study provides a theoretical foundation for evaluating the toxicological effects of bisphenols on the early development of aquatic organisms.

CircRNA CircABCB1 Diminishes the Sensitivity of Breast Cancer Cells to Docetaxel by Sponging MiR-153-3p.

Resistance to docetaxel is a major problem to the success of docetaxel-based therapies for breast cancer. The present study was to identify the role of circABCB1 in altering the docetaxel resistance properties. Reverse transcription-quantitative PCR (qRT-PCR) was performed to quantify circABCB1 and miR-153-3p. The effects of circABCB1 on the viability, apoptosis and migration/invasion of docetaxel-resistant and -sensitive cells were investigated by cell function experiments, including Cell Counting Kit-8 and Transwell assays. Correlation between circABCB1 and the docetaxel-treated outcome was analyzed by multivariate Cox regression analysis, in addition to Kaplan-Meier analysis of time to treatment failure (TTF). The targeting relationship between circABCB1 and miR-153-3p was predicted and verified by dual-luciferase reporter assay and RNA immunoprecipitation. CircABCB1 was highly expressed in cancerous tissues, as well as the docetaxel-sensitive group and cells. The overexpression of circABCB1 contributed to cell viability, docetaxel-resistance and migration/invasion, but inhibited apoptosis. CircABCB1 can sponge miR-153-3p. CircABCB1 contributed to the docetaxel resistance of breast cancer, maybe via the miR-153-3p.

circRNA_0001006 predicts prognosis and regulates cellular processes of triple-negative breast cancer via miR-424-5p.

BACKGROUND: circular RNAs (circRNAs) have been considered novel biomarker candidates for human cancers, such as triple-negative breast cancer (TNBC). circ_0001006 was identified as a differentially expressed circRNA in metastatic breast cancer, but its significance and function in TNBC were unclear. The significance of circ_0001006 in TNBC was assessed and exploring its potential molecular mechanism to provide a therapeutic target for TNBC. RESULTS: circ_0001006 showed significant upregulation in TNBC and close association with patients' histological grade, Ki67 level, and TNM stage. Upregulated circ_0001006 could predict a worse prognosis and high risk of TNBC patients. In TNBC cells, silencing circ_0001006 suppressed cell proliferation, migration, and invasion. In mechanism, circ_0001006 could negatively regulate miR-424-5p, which mediated the inhibition of cellular processes by circ_0001006 knockdown. CONCLUSIONS: Upregulated circ_0001006 in TNBC served as a poor prognosis predictor and tumor promoter via negatively regulating miR-424-5p.

Hepatitis E Virus Seroprevalence Indicated a Significantly Increased Risk Selectively in Patients with Gastric Cancer among 17 Common Malignancies.

Background: The impact of hepatitis E virus (HEV) infection on cancer development has been poorly investigated. This study aimed to explore the relationship between HEV seroprevalence and cancer risks and to identify high cancer risk subgroups in HEV-exposed populations. Methods: HEV seroprevalence status was determined in cancer and non-cancer subjects. Logistic regression and sensitivity analyses were used to assess the relationship between HEV antibody seropositivity and cancer risk for 17 cancer types. Additionally, interaction analyses were applied to interpret the association of HEV seroprevalence and other cancer risk factors. Results: Of the enrolled 4948 cancer and 4948 non-cancer subjects, cancer subjects had a higher anti-HEV seropositivity than non-cancer subjects (46.36% vs. 32.50%, p < 0.01). However, this divergency varied in degrees across different cancer types. Additionally, HEV seroprevalence was associated with cancer risk in young males (OR: 1.64, 95% CI: 1.19−2.27, p < 0.01). Remarkably, a significant association between HEV seroprevalence and cancer risk was observed only in gastric cancer patients (OR: 1.82, 95% CI: 1.07−3.09, p = 0.03). Conclusions: HEV seroprevalence was associated with cancer risk selectively in gastric cancer patients and young males, suggesting that cancer screening, particularly gastric cancer, should be regularly performed in young males with a history of HEV exposure.

Immunosuppressive role of SPP1-CD44 in the tumor microenvironment of intrahepatic cholangiocarcinoma assessed by single-cell RNA sequencing.

PURPOSE: To demonstrate the biological function of Secreted Phosphoprotein 1(SPP1) and its immune suppressive role in the progression intrahepatic cholangiocarcinoma (ICC). METHODS: We collected 62,770 cells' published transcriptome data of nine patients whose paired adjacent liver and tumor tissues were both available. We applied differential gene expression analysis to screen potential ICC marker genes, survival analysis to verify the prognostic value of SPP1, and correlation analysis to decipher factors that are related to SPP1 expression. The CellChat was used to distinguish interactions between cancer and T cells. CytoSig was applied to query cytokines that modulate CD44. Further, we established a proliferation score and correlated the score with inhibitory signals to determine the proliferation-suppressive function of SPP1-CD44. RESULTS: SPP1 expression is significantly upregulated in tumoral epitheliums, and patients with higher SPP1 expression have worse survival (P < 0.05). Tumor cells communicate with T cells via SPP1-CD44 interactions. The average expression of SPP1 in malignant cells (SPP1m) and CD44 in T cells (CD44t) is moderately negatively correlated with T cell proliferation score. Immunosuppressive cytokine TGFß-3 identified as an inducer of CD44 and was significantly negatively correlated with proliferation score (R = - 0.88, P < 0.01), and the negative correlation was aggravated in samples with high CD44 expression. CONCLUSION: SPP1 is a prognostic marker of ICC and is associated with the genome heterogeneity. SPP1-CD44 hinders sustained proliferation of T cells, but immunosuppressive T cells in the tumor microenvironment may evade this inhibition by reducing CD44 expression.

A neglected cervicovesical fistula diagnosed and repaired by combined hysteroscopy and laparoscopy: A case report and review of literature.

Objective: To analyze a case of neglected cervicovesical fistula with intrauterine adhesions caused by cesarean section. Methods: A 36-year-old female patient with a history of two previous cesarean sections complained of the absence of menstruation for the last 18 months. The diagnosis of the cervicovesical fistula was made through hysteroscopy and cystoscopy. The reconstruction of the uterus and bladder was achieved by a laparoscopic repair technique. Results: The patient resumed normal menstruation postoperatively without complaining of any complications. Uterine continuity and cavity had been restored to normal at the second look of hysteroscopy. Conclusions: Cervicovesical fistula with intrauterine adhesions is very rare in our clinical work. Hysteroscopy might play an essential role in diagnosing cervicovesical fistula and IUA. In our literature review, a surgical approach was the mainstay and definitive management of the cervicovesical fistula following a cesarean section.

Improvement of the carbon yield from biomass carbonization through sulfuric acid pre-dehydration at room temperature.

The pre-dehydration of a woody biomass waste (Douglas fir, DF) with 4.6-32 wt% of diluted sulfuric acid solutions was carried out mainly at room temperature aimed to improve the carbon yield from the thermal carbonization of pre-dehydrated biomass at 500 °C. By comparison (based on the raw DF), the pre-dehydration at room temperature increased the biochar yield and carbon retention up to about 32 wt% and 54%, respectively from that of about 22 wt% and 39% without pre-dehydration. When the pre-dehydration temperature increased to 90 °C, the biochar yield and carbon retention were sharply promoted to about 44 wt% and 76%, which was about two times higher than that of the biochar obtained without pre-treatment. This work for the first time proved the effectiveness of improving the carbon yield from lignocellulosic biomass via diluted sulfuric acid-assisted pre-dehydration at low or even room temperature.

Maternal inheritance of glucose intolerance via oocyte TET3 insufficiency.

Diabetes mellitus is prevalent among women of reproductive age, and many women are left undiagnosed or untreated1. Gestational diabetes has profound and enduring effects on the long-term health of the offspring2,3. However, the link between pregestational diabetes and disease risk into adulthood in the next generation has not been sufficiently investigated. Here we show that pregestational hyperglycaemia renders the offspring more vulnerable to glucose intolerance. The expression of TET3 dioxygenase, responsible for 5-methylcytosine oxidation and DNA demethylation in the zygote4, is reduced in oocytes from a mouse model of hyperglycaemia (HG mice) and humans with diabetes. Insufficient demethylation by oocyte TET3 contributes to hypermethylation at the paternal alleles of several insulin secretion genes, including the glucokinase gene (Gck), that persists from zygote to adult, promoting impaired glucose homeostasis largely owing to the defect in glucose-stimulated insulin secretion. Consistent with these findings, mouse progenies derived from the oocytes of maternal heterozygous and homozygous Tet3 deletion display glucose intolerance and epigenetic abnormalities similar to those from the oocytes of HG mice. Moreover, the expression of exogenous Tet3 mRNA in oocytes from HG mice ameliorates the maternal effect in offspring. Thus, our observations suggest an environment-sensitive window in oocyte development that confers predisposition to glucose intolerance in the next generation through TET3 insufficiency rather than through a direct perturbation of the oocyte epigenome. This finding suggests a potential benefit of pre-conception interventions in mothers to protect the health of offspring.

Improved FCOS for Detecting Breast Cancers.

PURPOSE: Breast cancer ranks first among cancers affecting women's health. Our goal is to develop a fast, high-precision, and fully automated breast cancer detection algorithm to improve the early detection rate of breast cancer. METHODS: We compare different object detection algorithms, including anchor-based and anchor-free object detection algorithms for detecting breast lesions. Finally, we find that the fully convolutional onestage object detection (FCOS) showed the best performance in the detection of breast lesions, which is an anchor-free algorithm. 1) Considering that the detection of breast lesions requires the context information of the ultrasound images, we introduce the non-local technique, which models long-range dependency between pixels to the FCOS algorithm, providing the global context information for the detection of the breast lesions. 2) The variety of shapes and sizes of breast lesions makes detection difficult. We propose a new deformable spatial attention (DSA) module and add it to the FCOS algorithm. RESULTS: The detection performance of the original FCOS is that the average precision (AP) for benign lesions is 0.818, and for malignant lesions is 0.888. The FCOS with a non-local module improves the performance of the breast detection; the AP of benign lesions was 0.819, and that of malignant lesions was 0.894. Combining the DSA module with the FCOS improves the performance of breast detection; the AP for benign lesions and malignant lesions is 0.840 and 0.899, respectively. CONCLUSION: We propose two methods to improve the FCOS algorithm from different perspectives to improve its performance in detecting breast lesions. We find that FCOS combined with DSA is beneficial in improving the localization and classification of breast tumors and can provide auxiliary diagnostic advice for ultrasound physicians, which has a certain clinical application value.

Intrauterine administration of G-CSF for promoting endometrial growth after hysteroscopic adhesiolysis: a randomized controlled trial.

STUDY QUESTION: Does intrauterine infusion of granulocyte colony-stimulating factor (G-CSF) prevent adhesion reformation and promote endometrial growth after hysteroscopic adhesiolysis? SUMMARY ANSWER: Intrauterine perfusion of G-CSF can increase endometrial thickness but does not prevent the recurrence of intrauterine adhesions (IUAs) in patients with Asherman syndrome (AS) after surgery. WHAT IS KNOWN ALREADY: Intrauterine infusion of G-CSF has been used in attempts to treat patients with recurrent miscarriage and an idiopathic thin endometrium for either fresh or frozen-thawed embryo transfer cycles but without uniform efficacy. There have been no reports on the effect of G-CSF on the recurrence of IUAs, endometrial regrowth or pregnancy results in specific populations with AS. STUDY DESIGN, SIZE, DURATION: This two-center prospective double-blind randomized controlled trial ran between April 2016 and August 2021. In it, 245 patients with moderate to severe AS were randomized to G-CSF and control groups at a 1:1 ratio; 229 women were included in the adhesion recurrence analysis; and 164 patients were analyzed for pregnancy outcomes. PARTICIPANTS/MATERIALS, SETTING, METHODS: All eligible patients received the first hysteroscopic adhesion separation and balloon placement procedure. Patients who met our inclusion and exclusion criteria were randomized after surgery. These patients returned for balloon removal and underwent intrauterine perfusion with 300 µg (1.8 ml) G-CSF or 1.8 ml normal saline according to randomization at 7 days after surgery. A second-look hysteroscopy was carried out 1-2 months later. The primary outcome was the rate of formation of new adhesions at the second hysteroscopy. The secondary outcomes included endometrial thickness in the periovulatory period after surgery, as well as the clinical pregnancy and live birth rates. MAIN RESULTS AND THE ROLE OF CHANCE: Age, menstrual cycle characteristics, pregnancy history and IUA score before surgery were similar between groups. There were no statistically significant differences in the adhesion reformation rate or median adhesion score reduction. However, G-CSF perfusion significantly improved endometrial thickness (7.91 ± 2.12 mm vs 7.22 ± 2.04 mm; P = 0.019, 95% CI for difference: -1.26 to -0.12), as well as cumulative pregnancy and live birth rate over time (P = 0.017 and P = 0.042). Furthermore, multivariate logistic regression analysis showed that postoperative endometrial thickness was an independent prognostic factor for pregnancy and live birth rates. LIMITATIONS, REASONS FOR CAUTION: These results cannot be extended to older patients or those without AS, as our subjects had moderate or severe AS and were aged <40 years. The low number of patients included in the fertility analysis could lead to biased results. WIDER IMPLICATIONS OF THE FINDINGS: Intrauterine perfusion of G-CSF could be an effective adjuvant therapy for patients with AS to increase endometrial thickness. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by grants from the National Key Research and Development Program of China (2018YFC1004800), the National Natural Science Foundation of China (82001624 and 81871209), the Natural Science Foundation of Zhejiang Province (LQ20H040004) and the provincial and ministerial construction project of Zhejiang Province (2017 WKJ-ZJ-1721). The authors declare that they have no conflicts of interest regarding this work. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT02855632). TRIAL REGISTRATION DATE: 4 March 2016. DATE OF FIRST PATIENT'S ENROLMENT: 13 April 2016.

OTP970 Is Required for RNA Editing of Chloroplast ndhB Transcripts in Arabidopsis thaliana.

RNA editing is essential for compensating for defects or mutations in haploid organelle genomes and is regulated by numerous trans-factors. Pentatricopeptide repeat (PPR) proteins are the prime factors that are involved in RNA editing; however, many have not yet been identified. Here, we screened the plastid-targeted PLS-DYW subfamily of PPR proteins belonging to Arabidopsis thaliana and identified ORGANELLE TRANSCRIPT PROCESSING 970 (OTP970) as a key player in RNA editing in plastids. A loss-of-function otp970 mutant was impaired in RNA editing of ndhB transcripts at site 149 (ndhB-C149). RNA-immunoprecipitation analysis indicated that OTP970 was associated with the ndhB-C149 site. The complementation of the otp970 mutant with OTP970 lacking the DYW domain (OTP970∆DYW) failed to restore the RNA editing of ndhB-C149. ndhB gene encodes the B subunit of the NADH dehydrogenase-like (NDH) complex; however, neither NDH activity and stability nor NDH-PSI supercomplex formation were affected in otp970 mutant compared to the wild type, indicating that alteration in amino acid sequence is not necessary for NdhB function. Together, these results suggest that OTP970 is involved in the RNA editing of ndhB-C149 and that the DYW domain is essential for its function.