N-doped pinecone-based carbon with a hierarchical porous pie-like structure: a long-cycle-life anode material for potassium-ion batteries.

Pinecone-based biomass carbon (PC) is a potential anode material for potassium-ion batteries because it is abundant, cheap, renewable, and easy to obtain. However, because of inferior kinetics and the effects of volume expansion due to the large radius of the K+ ion, it does not meet commercial performance requirements. In this study, nitrogen-doped PC (NPC) was prepared by carbonization in molten ZnCl2 with urea as a nitrogen source. A strategy based on synergistic effects between N doping and ZnCl2 molten salt was used to produce a hierarchically porous pie-like NPC with abundant defects and active sites and an enlarged interlayer distance-properties that enhance K+ adsorption, promote K+ intercalation/diffusion, and reduce the effects of volume expansion. This NPC exhibited a high reversible capacity (283 mA h g-1 at 50 mA g-1) and superior rate performance and cyclic stability (110 mA h g-1 after 1000 cycles at 5 A g-1), demonstrating its potential for use in potassium-ion batteries.

Boron-Doped Pine-Cone Carbon With 3D Interconnected Porosity for Use as an Anode for Potassium-Ion Batteries With Long Life Cycle.

Potassium-ion batteries (KIBs) have received widespread attention as an alternative to lithium-ion batteries because of their low cost and abundance of potassium. However, the poor kinetic performance and severe volume changes during charging/discharging due to the large radius of potassium leading to low capacity and rapid decay. Therefore, development of anode materials with sufficient space and active sites for potassium ion deintercalation and desorption is necessary to ensure structural stability and good electrochemical activity. This study prepared boron-doped pine-cone carbon (BZPC) with 3D interconnected hierarchical porous in ZnCl2 molten-salt by calcination under high temperature. The hierarchical porous structure promoted the penetration of the electrolyte, improved charge-carrier diffusion, alleviated volume changes during cycling, and increased the number of micropores available for adsorbing potassium ions. In addition, due to B doping, the BZPC material possessed abundant defects and active centers, and a wide interlayer distance, which enhanced the adsorption of K ions and promoted their intercalation and diffusion. When used as the anode of a KIB, BZPC provided a high reversible capacity (223.8 mAh g-1 at 50 mA g-1), excellent rate performance, and cycling stability (115.9 mAh g-1 after 2000 cycles at 1 A g-1).

Dynamic Imaging Changes of COVID-19 Pneumonia at Different Stages.

INTRODUCTION: To investigate the Computed Tomography (CT) imaging characteristics and dynamic changes of COVID-19 pneumonia at different stages. METHODS: Forty-six patients infected with COVID-19 who had chest CT scans were enrolled, and CT scans were performed 4-6 times with an interval of 2-5 days. RESULTS: At the early stage (n=25), ground glass opacity was presented in 11 patients (11/25 or 44.0 %) and ground glass opacity mixed with consolidation in 13 (13/25 or 52.0 %) in the lung CT images. At the progressive stage (n=38), ground glass opacity was presented in only one patient (1/38 or 2.6 %) and ground glass opacity mixed with consolidation in 33 (33/38 or 86.8 %). In the early improvement stage (n=38), the imaging presentation was ground glass opacity alone in three patients (3/38 or 7.9 %) and ground glass opacity mixed with consolidation in 34 (34/38 or 89.5 %). In the late improvement (absorption) stage (n=33), the primary imaging presentation was ground glass presentation in eight patients (8/33 or 24.2 %) and ground glass opacity mixed with consolidation in 23 (23/33 or 69.7 %). The lesion reached the peak at 4-16 days after disease onset, and 26 (26/38 or 68.4 %) patients reached the disease peak within ten days. Starting from 6 to 20 days after onset, the disease began to be improved, with 30 (30/38 or 78.9 %) patients being improved within 15 days. CONCLUSION: COVID-19 pneumonia will progress to the peak stage at a mediate time of seven days and enter the improvement stage at twelve days. Computed tomography imaging of the pulmonary lesion has a common pattern from disease onset to improvement and recovery and provides important information for evaluation of the disease course and treatment effect.

Organisational innovation climate and innovation behaviour among nurses in China: A mediation model of psychological empowerment.

AIM: This study aimed to explore the effect of organisational innovation climate on nurse innovation behaviour and the mediating role of psychological empowerment. BACKGROUND: Encouraging nurses to generate more innovative behaviours has become an important development direction for improving the quality of nursing services. METHOD: We employed a self-report questionnaire to collect data in Jinan City, China. A total of 2018 valid surveys were obtained. Hierarchical multiple regression model analysis was conducted to test the study hypothesis. RESULT: The mean values of innovation behaviour and organisational innovation climate were 35.29 and 83.30, respectively. Psychological empowerment was found to have partially mediating effect on the relationship between organisational innovation climate and innovation behaviour. CONCLUSION: Organisational innovation climate has significant impact on innovation behaviour, and it can indirectly affect innovation behaviour via the mediating role of psychological empowerment. IMPLICATIONS FOR NURSING MANAGEMENT: Nursing managers should enhance innovation climate through formal rules, procedures and training activities. They can establish resource guarantee system and information sharing platform, and strengthen work autonomy for nurses to improve their psychological empowerment.

Proton solvent-controllable synthesis of manganese oxalate anode material for lithium-ion batteries.

Manganese oxalates with different structures and morphologies were prepared by the precipitation method in a mixture of dimethyl sulfoxide (DMSO) and proton solvents. The proton solvents play a key role in determining the structures and morphologies of manganese oxalate. Monoclinic MnC2O4·2H2O microrods are prepared in H2O-DMSO, while MnC2O4·H2O nanorods and nanosheets with low crystallinity are synthesized in ethylene glycol-DMSO and ethanol-DMSO, respectively. The corresponding dehydrated products are mesoporous MnC2O4 microrods, nanorods, and nanosheets, respectively. When used as anode material for Li-ion batteries, mesoporous MnC2O4 microrods, nanorods, and nanosheets deliver a capacity of 800, 838, and 548 mA h g-1 after 120 cycles at 8C, respectively. Even when charged/discharged at 20C, mesoporous MnC2O4 nanorods still provide a reversible capacity of 647 mA h g-1 after 600 cycles, exhibiting better rater performance and cycling stability. The electrochemical performance is greatly influenced by the synergistic effect of surface area, morphology, and size. Therefore, the mesoporous MnC2O4 nanorods are a promising anode material for Li-ion batteries due to their good cycle stability and rate performance.

Clinical and imaging features of pediatric COVID-19.

BACKGROUND: Pediatric COVID-19 is relatively mild and may vary from that in adults. This study was to investigate the epidemic, clinical, and imaging features of pediatric COVID-19 pneumonia for early diagnosis and treatment. METHODS: Forty-one children infected with COVID-19 were analyzed in the epidemic, clinical and imaging data. RESULTS: Among 30 children with mild COVID-19, seven had no symptoms, fifteen had low or mediate fever, and eight presented with cough, nasal congestion, diarrhea, headache, or fatigue. Among eleven children with moderate COVID-19, nine presented with low or mediate fever, accompanied with cough and runny nose, and two had no symptoms. Significantly (P < 0.05) more children had a greater rate of cough in moderate than in mild COVID-19. Thirty children with mild COVID-19 were negative in pulmonary CT imaging, whereas eleven children with moderate COVID-19 had pulmonary lesions, including ground glass opacity in ten (90.9%), patches of high density in six (54.5%), consolidation in three (27.3%), and enlarged bronchovascular bundles in seven (63.6%). The lesions were distributed along the bronchus in five patients (45.5%). The lymph nodes were enlarged in the pulmonary hilum in two patients (18.2%). The lesions were presented in the right upper lobe in two patients (18.1%), right middle lobe in one (9.1%), right lower lobe in six (54.5%), left upper lobe in five (45.5%), and left lower lobe in eight (72.7%). CONCLUSIONS: Children with COVID-19 have mild or moderate clinical and imaging presentations. A better understanding of the clinical and CT imaging helps ascertaining those with negative nucleic acid and reducing misdiagnosis rate for those with atypical and concealed symptoms.

Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.

PURPOSE: To investigate the clinical and imaging characteristics of computed tomography (CT) in novel coronavirus pneumonia (NCP) caused by SARS-CoV-2. MATERIALS AND METHODS: A retrospective analysis was performed on the imaging findings of patients confirmed with COVID-19 pneumonia who had chest CT scanning and treatment after disease onset. The clinical and imaging data were analyzed. RESULTS: Fifty patients were enrolled, including mild type in nine, common in 28, severe in 10 and critically severe in the rest three. Mild patients (29 years) were significantly (P<0.03) younger than either common (44.5 years) or severe (54.7) and critically severe (65.7 years) patients, and common patients were also significantly (P<0.03) younger than severe and critically severe patients. Mild patients had low to moderate fever (<39.1 °C), 49 (98%) patients had normal or slightly reduced leukocyte count, 14 (28%) had decreased counts of lymphocytes, and 26 (52%) patients had increased C-reactive protein. Nine mild patients were negative in CT imaging. For all the other types of NCP, the lesion was in the right upper lobe in 30 cases, right middle lobe in 22, right lower lobe in 39, left upper lobe in 33 and left lower lobe in 36. The lesion was primarily located in the peripheral area under the pleura with possible extension towards the pulmonary hilum. Symmetrical lesions were seen in 26 cases and asymmetrical in 15. The density of lesion was mostly uneven with ground glass opacity as the primary presentation accompanied by partial consolidation and fibrosis. CONCLUSION: CT imaging presentations of NCP are mostly patchy ground glass opacities in the peripheral areas under the pleura with partial consolidation which will be absorbed with formation of fibrotic stripes if improved. CT scanning provides important bases for early diagnosis and treatment of NCP.

Inhibition of microRNA-21-5p reduces keloid fibroblast autophagy and migration by targeting PTEN after electron beam irradiation.

Electron beam (EB) irradiation is useful to reduce the recurrence of keloids; however, the underlying mechanism remains unknown. MicroRNA-21 (miR-21), which regulates autophagy during cancer radiation therapy, was identified as a potential therapeutic target for keloids. Here, we investigate the regulatory mechanism(s) of miR-21-5p on keloid fibroblast autophagy and migration after EB irradiation. The microRNA expression profile of the keloid dermis was examined by performing a microRNA microarray. Levels of LC3B and Beclin-1 were detected by immunohistochemical and western blot analysis in the keloid dermis and fibroblasts. Autophagy and apoptosis were tested in keloid fibroblasts after EB irradiation or transfection with an miR-21-5p inhibitor using electron microscopy, a Cyto-ID Green Autophagy Detection Kit, and an Annexin V PE Apoptosis Detection Kit. Migration was analyzed by an in vitro scratch-wound healing assay. Mechanistic tests were performed using small interfering RNAs to phosphatase and tensin homolog (siPTEN). Levels of miR-21-5p, PTEN, programmed cell death 4 (PDCD4), p-AKT, and apoptosis- and autophagy-associated genes were examined by qRT-PCR and western blotting. LC3B expression and migration ability were enhanced in fibroblasts and the keloid margin dermis compared with those in the adjacent normal skin. Both EB irradiation and an miR-21-5p inhibitor reduced keloid fibroblast autophagy, which was accompanied by decreased expression of miR-21-5p, p-AKT, and LC3B-II and increased expression of PTEN, PDCD4, and apoptosis-related genes. MiR-21-5p downregulation inhibited migration and suppressed LC3B expression and this was reversed by PTEN reduction. In conclusion, with increasing apoptosis, EB irradiation inhibits autophagy in keloid fibroblasts by reducing miR-21-5p, which regulates migration and LC3B expression via PTEN/AKT signaling. These data suggest a potential mechanism wherein miR-21-5p inhibition regulates autophagy and migration in EB-irradiated keloid fibroblasts, effectively preventing local invasion and recurrence. Therefore, miR-21-5p could be a new therapeutic target, to replace EB irradiation, and control keloid relapse.

Deep Eutectic Solvent Synthesis of LiMnPO4/C Nanorods as a Cathode Material for Lithium Ion Batteries.

Olivine-type LiMnPO4/C nanorods were successfully synthesized in a chloride/ethylene glycol-based deep eutectic solvent (DES) at 130 °C for 4 h under atmospheric pressure. As-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and electrochemical tests. The prepared LiMnPO4/C nanorods were coated with a thin carbon layer (approximately 3 nm thick) on the surface and had a length of 100-150 nm and a diameter of 40-55 nm. The prepared rod-like LiMnPO4/C delivered a discharge capacity of 128 mAh·g-1 with a capacity retention ratio of approximately 93% after 100 cycles at 1 C. Even at 5 C, it still had a discharge capacity of 106 mAh·g-1, thus exhibiting good rate performance and cycle stability. These results demonstrate that the chloride/ethylene glycol-based deep eutectic solvents (DES) can act as a new crystal-face inhibitor to adjust the oriented growth and morphology of LiMnPO4. Furthermore, deep eutectic solvents provide a new approach in which to control the size and morphology of the particles, which has a wide application in the synthesis of electrode materials with special morphology.

Integration of G-quadruplex and DNA-templated Ag NCs for nonarithmetic information processing.

To create sophisticated molecular logic circuits from scratch, you may not believe how common the building blocks can be and how diverse and powerful such circuits can be when scaled up. Using the two simple building blocks of G-quadruplex and silver nanoclusters (Ag NCs), we experimentally construct a series of multifunctional, label-free, and multi-output logic circuits to perform nonarithmetic functions: a 1-to-2 decoder, a 4-to-2 encoder, an 8-to-3 encoder, dual transfer gates, a 2 : 1 multiplexer, and a 1 : 2 demultiplexer. Moreover, a parity checker which is capable of identifying odd and even numbers from natural numbers is constructed conceptually. Finally, a multi-valued logic gate (ternary inhibit gate) is readily achieved by taking this DNA/Ag NC system as a universal platform. All of the above logic circuits share the same building blocks, indicating the great prospects of the assembly of nanomaterials and DNA for biochemical logic devices. Considering its biocompatibility, the novel prototypes developed here may have potential applications in the fields of biological computers and medical diagnosis and serve as a promising proof of principle in the not-too-distant future.

Fast Preparation of Porous MnO/C Microspheres as Anode Materials for Lithium-Ion Batteries.

Porous MnO/C microspheres have been successfully fabricated by a fast co-precipitation method in a T-shaped microchannel reactor. The structures, compositions, and electrochemical performances of the obtained MnO/C microspheres are characterized by X-ray diffraction, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller analysis, charge-discharge testing, cyclic voltammograms, and electrochemical impedance spectra. Experimental results reveal that the as-prepared MnO/C, with a specific surface area of 96.66 m²·g-1 and average pore size of 24.37 nm, exhibits excellent electrochemical performance, with a discharge capacity of 655.4 mAh·g-1 after cycling 50 times at 1 C and capacities of 808.3, 743.7, 642.6, 450.1, and 803.1 mAh·g-1 at 0.2, 0.5, 1, 2, and 0.2 C, respectively. Moreover, the controlled method of using a microchannel reactor, which can produce larger specific surface area porous MnO/C with improved cycling performance by shortening lithium-ion diffusion distances, can be easily applied in real production on a large scale.

Ultrasensitive and universal fluorescent aptasensor for the detection of biomolecules (ATP, adenosine and thrombin) based on DNA/Ag nanoclusters fluorescence light-up system.

We report here an ultrasensitive strategy based on the recognition-induced conformational alteration of aptamer and fluorescence turn-on abilities of guanine-rich (G-rich) DNA sequence in proximity to silver nanoclusters for adenosine triphosphate (ATP), adenosine (A) and thrombin (TB) detection. Herein, we designed two tailored DNA sequences noted as complementary DNA (abbreviated as c-DNA) and signal probe DNA (abbreviated as s-DNA), respectively. c-DNA is designed as a special structure consisting of a sequence complementary to aptamer at the 3'-end and a guanine-rich DNA sequence at the 5'-end; s-DNA contains a cytosine-rich sequence responsible for Ag NCs templated synthesis at the 3'-end and a link sequence (part of aptamer) complementary to partial of the c-DNA at the 5'-end. In the presence of target, the aptamer associated with the target, resulting in the formation of duplex DNA (dsDNA), the DNA-Ag NCs thereafter could close to the guanine-rich sequence, leading to enhanced fluorescence signal readout. The widespread application of the sensing system is achieved success in the detection of three biomolecules. ATP, adenosine and thrombin in the range of 0.5-8.0 µM, 0.5-7.0 µM and 50-900 nM could be linearly detected with the detection limits of 91.6 nM, 103.4 nM and 8.4 nM, respectively. This label-free and turn-on fluorescent sensing system employing the mechanism proposed here turns out to be sensitive, selective, and convenient for the detection of biomolecules without washing and separation steps.

Advantages of CyberKnife for inoperable stage I peripheral non-small-cell lung cancer compared to three-dimensional conformal radiotherapy.

This study was conducted to compare the clinical curative effect and acute radiation lung reactions between CyberKnife (CK) and three-dimensional conformal radiotherapy (3DCRT) treatment for inoperable stage I peripheral non-small-cell lung cancer (NSCLC). We retrospectively analyzed 68 patients with inoperable stage I peripheral NSCLC between 2012 and 2013 in our institution. The CK patients were treated with 42-60 Gy in three fractions, while the 3DCRT patients were treated with a total of 60 Gy, at 2 Gy per fraction. The patients were followed up and the clinical outcome was evaluated according to the Response Evaluation Criteria in Solid Tumours. We assessed the presence of acute radiation pneumonitis and pulmonary function status by thoracic scan and pulmonary function tests following CK and 3DCRT treatment. The binary univariate logistic regression analysis demonstrated that treatment method and forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC) prior to treatment (pre-FEV1/FVC) were the main factors affecting the risk of radiation pneumonitis. The analysis of these factors through multivariate logistic regression method demonstrated that treatment method for grade 1 and 2 [odds ratio (OR)= 7.866 and 11.334, respectively) and pre-FEV1/FVC for grade 1, 2 and 3 (OR = 5.062, 11.498 and 15.042, respectively) were significant factors affecting the risk of radiation pneumonitis (P<0.05). The 68 patients were divided into two subgroups using the threshold of pre-FEV1/FVC selected by the receiver operating characteristic curve. There were significant differences between the 3DCRT and CK treatment in both the pre-FEV1/FVC <68% and ≥68% subgroups for radiation pneumonitis (P=0.023 and 0.002, respectively). There was no statistically significant change in FVC, FEV1 and carbon monoxide diffusion capacity (DCLO) in the CK group, whereas there was a decrease in DCLO in the 3DCRT group. The complete remission rate was 40 vs. 34.2% at 1 year in the CK and 3DCRT groups, respectively. In conclusion, in this cohort of patients with inoperable stage I peripheral NSCLC, CK appears to be a safe and superior alternative to conventionally fractionated radiotherapy.

Isorhamnetin flavonoid synergistically enhances the anticancer activity and apoptosis induction by cis-platin and carboplatin in non-small cell lung carcinoma (NSCLC).

The development of novel antitumor drugs for the treatment of non-small cell lung carcinoma NSCLC is imperative in order to improve the efficacy of lung cancer therapy and prognosis. In the current study, we demonstrated the antitumor activity of isorhamnetin and its combinations with cisplatin and carboplatin against A-549 lung cancer cells. In order to assess the anticancer enhancing effect of isorhamnetin on cisplatin and carboplatin, A-549 cells were treated with isorhamnetin, cisplatin, carboplatin and their combinations and cell viability, cell apoptosis, cell cycle arrest as well as loss of mitochondrial membrane potential were evaluated by MTT assay, flow cytometry, confocal microscopy and fluorescence microscopy. The effect of the drugs on cancer cell migration, microtubule depolymerization as well activation of caspases was also studied. The results revealed that, as compared to single drug treatment, the combination of isorhamnetin with cisplatin and carboplatin resulted in greater effect in inhibiting cancer cell growth and inducing apoptosis. Combination of isorhamnetin with cisplatin and carboplatin resulted in more potent apoptosis induction as revealed by fluorescence microscopy using AO/PI double staining. Isorhamnetin and its combinations also triggered microtubule distortion and depolymerization. The combination of isorhamnetin with cisplatin and carboplatin increased the number of cells in G2/M phase dramatically as compared to single drug treatment. Moreover, isorhamnetin and its combinations with known anticancer drugs induced disruption of the mitochondrial membrane potential as well as activation of caspases 3, 9 and poly-(ADP-ribose) polymerase in A-549 cells. Isorhamnetin as well as its combinations with cisplatin and carboplatin resulted in inhibition of cancer cell migration significantly. Results of the current study suggest that isorhamnetin combinations with cisplatin and carboplatin might be a potential clinical chemotherapeutic approach for NSCLC.

Highly effective ex vivo gene manipulation to study kidney development using self-complementary adenoassociated viruses.

BACKGROUND: Ex vivo culture of intact embryonic kidney has become a powerful system for studying renal development. However, few methods have been available for gene manipulation and have impeded the identification and investigation of genes in this developmental process. RESULTS: Here we systemically compared eight different serotypes of pseudotyped self-complementary adenoassociated viruses (scAAVs) transduction in cultured embryonic kidney with a modified culture procedure. We demonstrated that scAAV was highly effective in delivering genes into and expressing in compacted tissues. scAAV serotypes 2 and 8 exhibited higher efficiency of transduction compared to others. Expression kinetics assay revealed that scAAV can be used for gene manipulation at the study of UB branching and nephrogenesis. Repressing WT1 in cultured kidney using shRNA impairs tubule formation. We for the first time employed and validated scAAV as a gene delivery tool in cultured kidney. CONCLUSIONS: These findings are expected to expedite the use of the ex vivo embryonic kidney cultures for kidney development research. For other ex vivo cultured organ models, scAAV could also be a promising tool for organogenesis study.

A study on the effect of aqueous extract of Lobelia chinensis on colon precancerous lesions in rats.

This paper studies the effects of Lobelia chinensis on colon precancerous lesions and on colonic epithelial proliferation and apoptosis in DMH-induced rats. After two weeks of feeding, 50 Wistar rats were randomly divided into five groups, namely the normal group, model group, Lobelia chinensis low-dose group, medium-dose group and high-dose group. Lobelia chinensis was made into ACF model, and administered to experimental groups for 10 consecutive weeks. Control group was given equivalent amount of normal saline. After feeding for 10 weeks, the rats in each group were sacrificed and the changes in colonic ACF number of rats in experimental groups were observed, and the inhibition rates were calculated. The results showed that among the rats fed for 24 h and 48 h, the number of apoptotic cells in colonic crypts of rats in DMH group did not differ significantly from the control group, while the difference was obvious between the control group and Lobelia chinensis treatment groups. The medium and high doses, that is, 0.45 g/kg and 1.35 g/kg can significantly inhibit ACF formation (P<0.01). The inhibition rates of low, medium and high doses were 8.12%, 59.42% and 65.44%, respectively.

Enhancement of sodium caprate on intestine absorption and antidiabetic action of berberine.

Berberine, a plant alkaloid used in traditional Chinese medicine, has a wide spectrum of pharmacological actions, but the poor bioavailability limits its clinical use. The present aim was to observe the effects of sodium caprate on the intestinal absorption and antidiabetic action of berberine. The in situ, in vitro, and in vivo models were used to observe the effect of sodium caprate on the intestinal absorption of berberine. Intestinal mucosa morphology was measured to evaluate the toxic effect of sodium caprate. Diabetic model was used to evaluate antidiabetic effect of berberine coadministered with sodium caprate. The results showed that the absorption of berberine in the small intestine was poor and that sodium caprate could significantly improve the poor absorption of berberine in the small intestine. Sodium caprate stimulated mucosal-to-serosal transport of berberine; the enhancement ratios were 2.08, 1.49, and 3.49 in the duodenum, jejunum, and ileum, respectively. After coadministration, the area under the plasma concentration-time curve of berberine was increased 28% than that in the absence of sodium caprate. Furthermore, both berberine and coadministration with sodium caprate orally could significantly decrease fasting blood glucose and improve glucose tolerance in diabetic rats (P < 0.05). The hypoglycemic effect of coadministration group was remarkably stronger, and the areas under the glucose curves was decreased 22.5%, compared with berberine treatment group (P < 0.05). Morphologic analysis indicated that sodium caprate was not significantly injurious to the intestinal mucosa. The study demonstrates that sodium caprate could significantly promote the absorption of berberine in intestine and enhance its antidiabetic effect without any serious mucosal damage.

MicroRNA-17 post-transcriptionally regulates polycystic kidney disease-2 gene and promotes cell proliferation.

To identify the possible microRNAs (miRNAs) which target the polycystic kidney disease-2 gene (PKD2), and clarify effects of the miRNAs on PKD2. We preliminarily used bioinformatics to analyze 3'UTR (3'untranslated regions) of PKD1 and PKD2 in order to predict the potential microRNAs targeted on them. Subsequently, the stable cell lines with overexpression of microRNA-17 (miR-17) were screened, and luciferase assay combined with the mutation 3'UTR of PKD2 were performed to verify PKD2 is the target of miR-17. Moreover, RT-PCR and Western Blotting were used to determine the post-transcriptionally regulation of PKD2 by miR-17. Finally, MTT cell assays allied with PKD2 rescued strategy were employed to evaluate cell proliferation effects. Our study firstly found that the 3'UTR of PKD2 was more conservation than that of PKD1, and microRNA-17 directly targets the 3'UTR of PKD2 and post-transcriptionally repress the expression of PKD2. Moreover, our findings also demonstrated that overexpression of miR-17 may promote cell proliferation via post-transcriptionally repression of PKD2 in HEK 293T. This suggested that microRNA might be a novel mechanism for cystogenesis as well as a potential therapeutic target for the cell proliferation of autosomal dominant polycystic kidney disease (ADPKD).

Down-regulation of Pkd2 by siRNAs suppresses cell-cell adhesion in the mouse melanoma cells.

The Pkd2 gene encodes an integral protein (~130 kDa), named polycystin-2 (PC-2). PC-2 is mainly involved in autosomal dominant polycystic kidney disease. Recently, polycystin-1/polycystin-2 complex has been shown to act as an adhesion complex mediating or regulating cell-cell or cell-matrix adhesion, suggesting that PC-2 may play a role in cell-cell/cell-matrix interactions. Here, we knocked down the expression of Pkd2 gene with small interfering RNAs (siRNAs) in the mouse melanoma cells (B16 cells), indicating that the cells transfected with the targeted siRNAs significantly suppressed cell-cell adhesion, but not cell-matrix adhesion, compared to the cells transfected with non-targeted control (NC) siRNA. This study provides the first directly functional evidence that PC-2 mediates cell-cell adhesion. Furthermore, we demonstrated that PC-2 modulated cell-cell adhesion may be, at least partially, associated with E-cadherin. Collectively, these findings for the first time showed that PC-2 may mediate cell-cell adhesion, at least partially, through E-cadherin.