GCR1 Positively Regulates UV-B- and Ethylene-Induced Stomatal Closure via Activating GPA1-Dependent ROS and NO Production.

Heterotrimeric G proteins function as key players in guard cell signaling to many stimuli, including ultraviolet B (UV-B) and ethylene, but whether guard cell G protein signaling is activated by the only one potential G protein-coupled receptor, GCR1, is still unclear. Here, we found that gcr1 null mutants showed defects in UV-B- and ethylene-induced stomatal closure and production of reactive oxygen species (ROS) and nitric oxide (NO) in guard cells, but these defects could be rescued by the application of a Gα activator or overexpression of a constitutively active form of Gα subunit GPA1 (cGPA1). Moreover, the exogenous application of hydrogen peroxide (H2O2) or NO triggered stomatal closure in gcr1 mutants and cGPA1 transgenic plants in the absence or presence of UV-B or ethylene, but exogenous ethylene could not rescue the defect of gcr1 mutants in UV-B-induced stomatal closure, and gcr1 mutants did not affect UV-B-induced ethylene production in Arabidopsis leaves. These results indicate that GCR1 positively controls UV-B- and ethylene-induced stomatal closure by activating GPA1-dependent ROS and NO production in guard cells and that ethylene acts upstream of GCR1 to transduce UV-B guard cell signaling, which establishes the existence of a classic paradigm of G protein signaling in guard cell signaling to UV-B and ethylene.

COP1 Mediates Dark-Induced Stomatal Closure by Suppressing FT, TSF and SOC1 Expression to Promote NO Accumulation in Arabidopsis Guard Cells.

RING-finger-type ubiquitin E3 ligase Constitutively Photomorphogenic 1 (COP1) and floral integrators such as FLOWERING LOCUS T (FT), TWIN SISTER OF FT (TSF) and SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) have been identified as regulators of stomatal movement. However, little is known about their roles and relationship in dark-induced stomatal closure. Here, we demonstrated that COP1 is required for dark-induced stomatal closure using cop1 mutant. The cop1 mutant closed stomata in response to exogenous nitric oxide (NO) but not hydrogen peroxide (H2O2), and H2O2 but not NO accumulated in cop1 in darkness, further indicating that COP1 acts downstream of H2O2 and upstream of NO in dark-induced stomatal closure. Expression of FT, TSF and SOC1 in wild-type (WT) plants decreased significantly with dark duration time, but this process was blocked in cop1. Furthermore, ft, tsf, and soc1 mutants accumulated NO and closed stomata faster than WT plants in response to darkness. Altogether, our results indicate that COP1 transduces H2O2 signaling, promotes NO accumulation in guard cells by suppressing FT, TSF and SOC1 expression, and consequently leads to stomatal closure in darkness. These findings add new insights into the mechanisms of dark-induced stomatal closure.

Ethylene-induced stomatal closure is mediated via MKK1/3-MPK3/6 cascade to EIN2 and EIN3.

Mitogen-activated protein kinases (MPKs) play essential roles in guard cell signaling, but whether MPK cascades participate in guard cell ethylene signaling and interact with hydrogen peroxide (H2 O2 ), nitric oxide (NO), and ethylene-signaling components remain unclear. Here, we report that ethylene activated MPK3 and MPK6 in the leaves of wild-type Arabidopsis thaliana as well as ethylene insensitive2 (ein2), ein3, nitrate reductase1 (nia1), and nia2 mutants, but this effect was impaired in ethylene response1 (etr1), nicotinamide adenine dinucleotide phosphate oxidase AtrbohF, mpk kinase1 (mkk1), and mkk3 mutants. By contrast, the constitutive triple response1 (ctr1) mutant had constitutively active MPK3 and MPK6. Yeast two-hybrid, bimolecular fluorescence complementation, and pull-down assays indicated that MPK3 and MPK6 physically interacted with MKK1, MKK3, and the C-terminal region of EIN2 (EIN2 CEND). mkk1, mkk3, mpk3, and mpk6 mutants had typical levels of ethylene-induced H2 O2 generation but impaired ethylene-induced EIN2 CEND cleavage and nuclear translocation, EIN3 protein accumulation, NO production in guard cells, and stomatal closure. These results show that the MKK1/3-MPK3/6 cascade mediates ethylene-induced stomatal closure by functioning downstream of ETR1, CTR1, and H2 O2 to interact with EIN2, thereby promoting EIN3 accumulation and EIN3-dependent NO production in guard cells.

Stent with radioactive seeds strand insertion for malignant hilar biliary obstruction.

PURPOSE: This study aimed to assess clinical efficacy and long-term patient outcomes in individuals with malignant hilar biliary obstruction (MHBO) that had been treated via insertion of a stent with a radioactive seed strand (RSS). MATERIAL AND METHODS: A total of 84 MHBO patients were treated via either normal stent insertion (n = 48) or stent with RSS insertion (n = 36) from January 2015 to December 2018. RESULTS: The technical success rates of normal stent insertion and stent with RSS insertion were 93.8% (45/48) and 97.2% (35/36), respectively (p = .632), with clinical success rates of 93.3% (42/45) and 100% (35/35), respectively (p = .252). In these two patient groups, 11 and seven patients, respectively, suffered from stent dysfunction (p = .637). In the normal and RSS groups, median stent patency was 165 and 225 days, respectively (p < .001). All patients in the present study died due to tumor progression, with median survival times of 188 and 250 days in the normal and RSS stent groups, respectively (p < .001). CONCLUSION: Relative to normal stent insertion, combined stent with RSS insertion can effectively prolong both stent patency and patient survival in patients with MHBO.

Indocyanine green clearance in evaluating the recovery of liver reserve function after superselective transarterial chemoembolization.

Transarterial chemoembolization (TACE) may ravage normal liver tissues apart from the neoplastic nodules which offset the anti-tumor effect. This study aimed to evaluate the recovery of liver reserve function (LRF) after TACE by indocyanine green (ICG) clearance test and other routine liver function tests. Forty-six newly diagnosed HCC patients who had undergone TACE as the initial treatment from January 2011 to January 2012 were enrolled in this study. The effects of age, basic ICG clearance rate and interval time between two assessments on the recovery of LRF were analyzed. We found that ICG retention rate at the 15 minutes (ICGR15) was significantly increased after TACE (12.3+/-8.1% vs 16.8+/-12.1%, P<0.01) in all the 46 patients. In particular, the ICGR15 value was increased in older patients (age>55 years, 20.3+/-12.5% vs 13.7+/-7.2%, P<0.01). The interval of ICG test also affected the ICGR15 value (≤47 days, 17.8+/-11.4% after vs 12.1+/-7.1% before TACE, P<0.01). Our data suggested that TACE decreased LRF, especially in older patients. ICG test was more sensitive to evaluate the recovery of LRF after TACE than the Child-Pugh grade and routine liver function tests.

Recurrent retroperitoneal Schwannomas displaying different differentiation from primary tumor: case report and literature review.

BACKGROUND: Retroperitoneal Schwannomas are uncommonly found in the retroperitoneum and few of them show malignant transformation and invasion. Local recurrence are common in malignant Schwannomas with very few reports of tumor distinct differentiation at recurrences. CASE PRESENTATION: We report here a rare case of retroperitoneal schwannoma with multiple origins from retroperitoneum and pelvic wall. Pathological examination confirmed the case as a schwannoma with malignant transformation. Radical dissection of the tumors along with the sacrifice of adjacent sigmoid colon and left kidney failed to provide a cure for this patient. Due to tumor recurrence, a second and a third surgery of radical excision were performed 6 months and 17 months later after the first surgery, respectively. Histopathologic analysis identified that the recurrent tumors were different from the original schwannoma because of their smooth muscle-like differentiation. CONCLUSION: Malignant schwannomas are uncommon sarcomas with a high incidence of local recurrence. Distinct immunohistochemical staining results of the tumors at recurrence indicate their potential of smooth-muscle like differentiation. Radical excision of the tumors may provide benefit for their local recurrences.

Human Bone Marrow Mesenchymal Stem Cell-derived Exosomes Attenuate IL-1ß-induced Annulus Fibrosus Cell Damage.

BACKGROUND: Intervertebral disc degeneration (IDD) has high morbidity and high disability. Exosomes as a favorable candidate for IDD treatment is a hot spot of current research. METHODS: Exosomes were obtained from bone marrow mesenchymal stem cells (BM-MSCs) of patients with non-open femoral fractures. Then, annulus fibrosus (AF) cells were treated with IL-1ß, IL-1ß combined with exosomes or IL-1ß combined with exosomes and rapamycin. Flow cytometry and CCK-8 assay were performed to explore the apoptosis and cell proliferation. Quantitative real-time PCR and western blot were performed to detect the gene and protein expression. RESULTS: Exosomes were obtained from BM-MSCs successfully. BM-MSC-derived exosomes suppressed IL-1ß-induced inflammation and apoptosis and promoted cell proliferation of AF cells. BM-MSC-derived exosomes inhibited autophagy of AF cells by activating PI3K/AKT/mTOR signaling pathway. The effect of BM-MSC-derived exosomes on inflammation and apoptosis of AF cells was rescued by rapamycin. CONCLUSIONS: In conclusion, our study revealed that BM-MSC-derived exosomes inhibited IL-1ß-induced inflammation and apoptosis of AF cells by suppressing autophagy.

Comparing the performance of time series models with or without meteorological factors in predicting incident pulmonary tuberculosis in eastern China.

BACKGROUND: Many studies have compared the performance of time series models in predicting pulmonary tuberculosis (PTB), but few have considered the role of meteorological factors in their prediction models. This study aims to explore whether incorporating meteorological factors can improve the performance of time series models in predicting PTB. METHODS: We collected the monthly reported number of PTB cases and records of six meteorological factors in three cities of China from 2005 to 2018. Based on this data, we constructed three time series models, including an autoregressive integrated moving average (ARIMA) model, the ARIMA with exogenous variables (ARIMAX) model, and a recurrent neural network (RNN) model. The ARIMAX and RNN models incorporated meteorological factors, while the ARIMA model did not. The mean absolute percentage error (MAPE) and root mean square error (RMSE) were used to evaluate the performance of the models in predicting PTB cases in 2018. RESULTS: Both the cross-correlation analysis and Spearman rank correlation test showed that PTB cases reported in the study areas were related to meteorological factors. The predictive performance of both the ARIMA and RNN models was improved after incorporating meteorological factors. The MAPEs of the ARIMA, ARIMAX, and RNN models were 12.54%, 11.96%, and 12.36% in Xuzhou, 15.57%, 11.16%, and 14.09% in Nantong, and 9.70%, 9.66%, and 12.50% in Wuxi, respectively. The RMSEs of the three models were 36.194, 33.956, and 34.785 in Xuzhou, 34.073, 25.884, and 31.828 in Nantong, and 19.545, 19.026, and 26.019 in Wuxi, respectively. CONCLUSIONS: Our study revealed a possible link between PTB and meteorological factors. Taking meteorological factors into consideration increased the accuracy of time series models in predicting PTB, and the ARIMAX model was superior to the ARIMA and RNN models in study settings.

UV RESISTANCE LOCUS8 mediates ultraviolet-B-induced stomatal closure in an ethylene-dependent manner.

Although the UV RESISTANCE LOCUS 8 (UVR8)-CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1)-ELONGATED HYPOCOTYL5 (HY5) signaling pathway, ethylene, hydrogen peroxide (H2O2), and nitric oxide (NO) all participate in ultraviolet-B (UV-B)-triggered stomatal closing, their interrelationship is not clear. Here, we found that UV-B-induced the expression of ethylene biosynthetic genes, production of ethylene, H2O2, and NO, and stomata closing were impaired in uvr8, cop1, and hy5 mutants. UV-B-induced NO production and stomata closing were also defective in mutants for ETHYLENE RESPONSE 1 (ETR1), ETHYLENE INSENSITIVE 2 (EIN2), and EIN3, but UV-B-triggered H2O2 generation was only inhibited in etr1. In either the absence or presence of UV-B, ethylene triggered H2O2 production but not NO generation and stomatal closure in cop1 and hy5, and stomata closing in cop1 and hy5 was induced by NO but not H2O2. Moreover, NO production and stomatal closure were constitutively caused by over-expression of COP1 or HY5 in ein2 and ein3, but not by over-expression of EIN2 or EIN3 in cop1 and hy5. Our data indicate that the UVR8-COP1-HY5 signaling module mediates UV-B-induced ethylene production, ethylene is then perceived by ETR1 to induce H2O2 synthesis. H2O2 induces NO generation and subsequent stomata closing via an EIN2, EIN3, COP1, and HY5-dependent pathway(s).

Ethylene mediates salicylic-acid-induced stomatal closure by controlling reactive oxygen species and nitric oxide production in Arabidopsis.

Both salicylic acid (SA) and ethylene induce stomatal closure and positively regulate stomatal immunity, but their interactions in guard cell signaling are unclear. Here, we observed that SA induced the expression of ethylene biosynthetic genes; the production of ethylene, reactive oxygen species (ROS) and nitric oxide (NO); and stomatal closure in Arabidopsis thaliana. However, SA-induced stomatal closure was inhibited by an ethylene biosynthetic inhibitor and mutations in ethylene biosynthetic genes, ethylene-signaling genes [RESPONSE TO ANTAGONIST 1 (RAN1), ETHYLENE RESPONSE 1 (ETR1), ETHYLENE INSENSITIVE 2 (EIN2), EIN3 and ARABIDOPSIS RESPONSE REGULATOR 2 (ARR2)], NADPH oxidase genes [ATRBOHD and ATRBOHF], and nitrate reductase genes (NIA1 and NIA2). Furthermore, SA-triggered ROS production in guard cells was impaired in ran1, etr1, AtrbohD and AtrbohF, but not in ein2, ein3 or arr2. SA-triggered NO production was impaired in all ethylene-signaling mutants tested and in nia1 and nia2. The stomata of mutants for CONSTITUTIVE TRIPLE RESPONSE1 (CTR1) showed constitutive ROS and NO production and closure. These results indicate that ethylene mediates SA-induced stomatal closure by activating ATRBOHD/F-mediated ROS synthesis in an RAN1-, ETR1- and CTR1-dependent manner. This in turn induces NIA1/2-mediated NO production and subsequent stomatal closure via the ETR1, EIN2, EIN3 and ARR2-dependent pathway(s).

The prognostic value of intermedin in patients with breast cancer.

This study aimed to evaluate the prognostic value of preoperative plasma intermedin levels in breast cancer patients. Plasma intermedin levels of 252 breast cancer women and 100 healthy women were determined using radioimmunoassay kit. Adverse event was defined as first local recurrence, distant metastasis, second primary cancer of another organ, or death from any cause during 5-year follow-up. Disease-free survival was defined as the time between surgery and the date of any adverse event whichever appeared first. Overall survival was defined from surgery to death for any cause. The relationships between plasma intermedin levels and clinical outcomes of breast cancer patients were evaluated using multivariate analysis. The results showed that preoperative plasma intermedin levels were substantially higher in patients than in healthy subjects using t-test. Intermedin was identified as an independent predictor for 5-year mortality, adverse event, disease-free survival, and overall survival using multivariate analysis. Based on receiver operating characteristic curve analysis, preoperative plasma intermedin levels had high predictive value for 5-year mortality and adverse event. In conclusion, preoperative plasma intermedin levels are highly associated with poor patient outcomes and intermedin may be a potential prognostic biomarker for patients with breast cancer.

[Establishment of biopanning model of phage display peptide library in the blood vessels of excised human osteosarcoma vasculature and its significance].

OBJECTIVE: To establish an in vivo biopanning model of phage display peptide library in the blood vessels contained in surgically removed human osteosarcoma. METHOD: In 28 patients with osteosarcoma, digital subtraction angiography (DSA) of the involved limb was performed preoperatively to understand the approximate status of the arteries in the tumors. The tumors were then surgically removed and carefully trimmed, perfused via a simulated Langendorff perfusion apparatus with the indexes as the pH value, temperature and O2 partial pressure monitored in the blood vessels. A 12-meres phage display peptide library was biopanned to isolate peptides capable of homing specifically to the excised osteosarcoma. RESULTS: In vivo biopanning models were successfully established in all the excised tumors, which could be directly used in perfusion experiment and the indexes monitored in the blood vessels in the tumors were comparable to those of living tissues. Some high-affinity peptides specific to the blood vessels in osteosarcoma were obtained with the motif of RLTR. CONCLUSION: In vivo biopanning model simulating the Langendorff perfusion apparatus can be easily established which is instrumental for the application of phage display technology in human living tissues and may facilitate the study of targeted chemotherapy of osteosarcoma.

[Survey on drug resistance of Staphylococcus to commonly used antibiotics].

OBJECTIVE: To obtain primary knowledge of drug resistance of Staphylococcus, especially methicillin-resistant Staphylococcus (MRS), so as to facilitate clinical decision over the choice of appropriate antibiotics. METHOD: A total of 105 strains of Staphylococcus aureus, Staphylococcus epidermidis and other coagulase-negative Staphylococcus,were isolated from blood, sputum, pus and secretion sample from in-patients of Nanfang Hospital from January to July, 2002, and their status of drug-resistance was examined. RESULTS: MRS was isolated from 68.8% of the samples, and 69.6% of these isolates were methicillin-resistant Staphylococcus aureus (MRSA) and 63.3% resistant Staphylococcus epidermidis (MRSE). The rate of multi-drug resistance for MRS was much higher than that for methicilllin-susceptible Staphylococcus (MSS), and MRSA showed high multidrug resistance rates (all>50%) to the antibiotics erythromycin, imipenem, amikacin, SXT, ciprofloxacin, which fell into 4 categories according to their different antibiotic mechanisms. CONCLUSIONS: The prevalence and high MDR rate of MRS isolated form the samples suggest that in cases of infection, identification of the pathogenic bacterium should be routinely performed. Besides controlling MRS infection, importance should also be given to its prevention.

[Identification of the binding site on ICAM-1 for red blood cells infected by Plasmodium falciparum].

OBJECTIVE: To identify the binding site on ICAM-1 to PRBCs in order to explore anti-adhesive agent against cerebral malaria. METHODS: Monoclonal antibody 15.2 against ICAM-1 domain 1 was chosen as target molecule to screen mimetic peptides of ICAM-1 from a 12-mer random peptide library. Three rounds of biopanning were carried out and then ELISA, competitive ELISA, dot-ELISA and Western blotting were used to evaluate the binding character between phage-borne peptides and McAb 15.2. The insert DNA sequences of positive clones were determined and their amino acid sequences were deduced. RESULTS: Thirty clones from the third round were randomly selected, and 26 of them were found positive by sandwich ELISA. The competitive ELISA test proved that most phage-borne peptides could competitively inhibit the binding of antibody (15.2 McAb) with ICAM-1. Analysis of DNA and amino acid sequences indicated that over a half positive phage clones expressed 12-mer peptide KLYLIAEGSVAA. Comparison of peptide K(XX) L(XXX) GSV with the 64-73 aa of primary sequence of ICAM-1 showed a 50% homogeneity. CONCLUSION: These peptides displayed by phage may be analogs of ICAM-1, K..L...GSV probably plays a significant role on the binding reaction of ICAM-1 and PRBCs.