Primulaxilingensis (Primulaceae), a new species from Sichuan, China.

A new species, Primulaxilingensis K.Huang & Z.X.Fu, sp. nov. (Primulaceae), is described and illustrated. In gross morphology, it is clearly allied to section Minutissimae on account of having stolons, being glabrous, leaf rosette less than or equal to corolla, flower solitary and bract not swollen at base. The new species is easily distinguished by the combination of scape densely yellow farinose, leaf apex acute, rarely broadly obtuse, corolla pale purplish blue and style 3.0-6.0 mm above base of corolla tube, stamens reaching the corolla tube mouth in thrum flower. In addition, the distribution map, morphological comparison of related species and conservation status of the new species are also provided.

Genome-wide identification and characterization of tomato 14-3-3 (SlTFT) genes and functional analysis of SlTFT6 under heat stress.

The plant 14-3-3 proteins are essential for many biological processes and responses to abiotic stress. We performed genome-wide identification and analysis of the 14-3-3 family genes in tomato. To explore the properties of the thirteen Sl14-3-3 found in the tomato genome, their chromosomal location, phylogenetic, and syntenic relationships were analyzed. The Sl14-3-3 promoters were found to have a number of growth-, hormone-, and stress-responsive cis-regulatory elements. Moreover, the qRT-PCR assay revealed that Sl14-3-3 genes are responsive to heat and osmotic stress. Subcellular localization experiments evidenced that the SlTFT3/6/10 proteins occur in the nucleus and cytoplasm Additional analysis on Sl14-3-3 putative interactor proteins revealed a number of prospective clients that potentially participate in stress reactions and developmental processes. Furthermore, overexpression of an Sl14-3-3 family gene, SlTFT6, improved tomato plants thermotolerance. Taken together, the study provides basic information on tomato 14-3-3 family genes in plant growth and abiotic stress response (high temperature stress), which can be helpful to further study the underlying molecular mechanisms.

A bHLH transcription factor, SlbHLH96, promotes drought tolerance in tomato.

Drought stress caused by water deficit reduces plant productivity in many regions of the world. In plants, basic helix-loop-helix (bHLH) transcription factors regulate a wide range of cellular activities related to growth, development and stress response; however, the role of tomato SlbHLHs in drought stress responses remains elusive. Here, we used reverse genetics approaches to reveal the function of SlbHLH96, which is induced by drought and abscisic acid (ABA) treatment. We found that SlbHLH96 functions as a positive regulator of drought tolerance in tomato. Overexpression of SlbHLH96 in tomato improves drought tolerance by stimulating the expression of genes encoding antioxidants, ABA signaling molecules and stress-related proteins. In contrast, silencing of SlbHLH96 in tomato reduces drought tolerance. SlbHLH96 physically interacts with an ethylene-responsive factor, SlERF4, and silencing of SlERF4 in tomato also decreases drought tolerance. Furthermore, SlbHLH96 can repress the expression of the ABA catabolic gene, SlCYP707A2, through direct binding to its promoter. Our results uncover a novel mechanism of SlbHLH96-mediated drought tolerance in tomato plants, which can be exploited for breeding drought-resilient crops.

Overexpression of SlBBX17 affects plant growth and enhances heat tolerance in tomato.

Heat stress is one of the major limiting factors that affect plant growth and production. In this study, we identified SlBBX17, which encodes a B-Box (BBX) protein and functions as a negative regulator of plant growth and a positive regulator of heat tolerance in tomato (Solanum lycopersicum). The expression of SlBBX17 is induced by hormones and heat stress. Overexpression of SlBBX17 (SlBBX17-OE) in tomato led to less chlorophyll content and lower net photosynthetic rate relative to the wild type. The growth retardation in the SlBBX17-OE plants may be attributed to the change of endogenous gibberellin (GA) metabolism and the decrease of photosynthetic capacity. SlBBX17-OE plants exhibited increased tolerance to heat stress, as reflected by the better membrane stability, higher antioxidant enzyme activities, and less reactive oxygen species (ROS) accumulation. Transcriptome analysis revealed that overexpression of SlBBX17 affected the expression of genes involved in GA biosynthetic process, photosynthesis, heat stress, ROS, and other cellular processes. The qRT-PCR analysis indicated that many SlHsf and SlHSP genes are up-regulated by SlBBX17 under heat stress. These results demonstrate that SlBBX17 plays important roles in regulating tomato growth and resistance to heat stress.

Multi-laser sensor for simultaneous multi-gas measurements using off-axis cavity-enhanced absorption spectroscopy with an opposite two-way configuration.

An opposite two-way off-axis cavity-enhanced absorption spectroscopy-based multi-gas sensor is reported. More than two lasers can be employed in the sensor for simultaneous detection of different gas species. An approximately two times improvement in magnitude of the 2f signal and the signal-to-noise ratio is achieved because the concave spherical mirrors outside each end of the cavity and the narrow bandpass filters before the detectors can act as re-injection mirrors to re-inject the light into the cavity in the scheme. The performance of the sensor is demonstrated by simultaneous measurement of CO2 and CH4 in the atmosphere. This Letter highlights a new, to the best of our knowledge, strategy for simultaneous multi-gas measurement in a single integrated cavity by employing as many as four lasers.

lncRNA AK054386 Functions as a ceRNA to Sequester miR-199 and Induce Sustained Endoplasmic Reticulum Stress in Hepatic Reperfusion Injury.

Hepatic ischemia-reperfusion injury (IRI) is a very complex pathological process that is often associated with liver trauma and surgery, especially liver transplantation surgery. Although endoplasmic reticulum stress (ERS) plays a role in this process, the posttranscriptional regulators and the underlying mechanisms are still unclear. Here, we report that the lncRNA AK054386 was increased in hepatic IRI models. Furthermore, AK054386 can act as a "competing endogenous RNA (ceRNA)" and regulate ERS-related factors by binding and sequestering miR-199, which was shown to inhibit ERS in our previous report. Increased expression of AK054386, which might be mediated by activated NF-κB, resulted in sustained ERS and increased cell apoptosis and death in hepatic IRI mouse and cellular models. In contrast, AK054386 inhibition had protective effects on these models. Our data indicate that AK054386 and miR-199 are critical players in hepatic IRI, and we broadened the scope regarding ceRNA mechanisms. We hope that our results will improve the understanding of hepatic IRI and may provide potential therapeutic targets.

Fushiming Capsule Attenuates Diabetic Rat Retina Damage via Antioxidation and Anti-Inflammation.

AIMS: Diabetic retinopathy (DR) remains one of the leading causes of acquired blindness. Fushiming capsule (FSM), a compound traditional Chinese medicine, is clinically used for DR treatment in China. The present study was to investigate the effect of FSM on retinal alterations, inflammatory response, and oxidative stress triggered by diabetes. MAIN METHODS: Diabetic rat model was induced by 6-week high-fat and high-sugar diet combined with 35 mg/kg streptozotocin (STZ). 30 days after successful establishment of diabetic rat model, full field electroretinography (ffERG) and optical coherence tomography (OCT) were performed to detect retinal pathological alterations. Then, FSM was administered to diabetic rats at different dosages for 42-day treatment and diabetic rats treated with Calcium dobesilate (CaD) capsule served as the positive group. Retinal function and structure were observed, and retinal vascular endothelial growth factor-α (VEGF-α), glial fibrillary acidic (GFAP), and vascular cell adhesion protein-1 (VCAM-1) expressions were measured both on mRNA and protein levels, and a series of blood metabolic indicators were also assessed. KEY FINDINGS: In DR rats, FSM (1.0 g/kg and 0.5 g/kg) treatment significantly restored retinal function (a higher amplitude of b-wave in dark-adaptation 3.0 and OPs2 wave) and prevented the decrease of retinal thickness including inner nuclear layer (INL), outer nuclear layer (ONL), and entire retina. Additionally, FSM dramatically decreased VEGF-α, GFAP, and VCAM-1 expressions in retinal tissues. Moreover, FSM notably improved serum antioxidative enzymes glutathione peroxidase, superoxide dismutase, and catalase activities, whereas it reduced serum advanced glycation end products, methane dicarboxylic aldehyde, nitric oxide, and total cholesterol and triglycerides levels. SIGNIFICANCE: FSM could ameliorate diabetic rat retina damage possibly via inhibiting inflammation and improving antioxidation.

BACE1-AS prevents BACE1 mRNA degradation through the sequestration of BACE1-targeting miRNAs.

Abnormal long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) participate in the pathophysiology of Alzheimer's disease (AD). However, it remains unclear whether these two types of noncoding RNAs functionally interact and which factors mediate these interactions in AD. ß-secretase 1 (BACE1) is the enzyme responsible for amyloid plaque formation, which is a central pathological feature of AD. The lncRNA BACE1-AS and some miRNAs have been implicated in the regulation of BACE1. In this study, we reveal that BACE1-AS shares many miRNA-response elements with BACE1. The overexpression of BACE1-AS results in the repression of miRNAs that target BACE1, thus preventing BACE1 mRNA from being degraded. The knockdown of BACE1-AS increases the levels of these miRNAs, thereby reducing the expression of BACE1. Thus, BACE1-AS functions as a competing endogenous RNA (ceRNA). Our results also deepen the understanding of the regulation of BACE1 by BACE1-AS. In addition to increasing the stability of BACE1 mRNA through the formation of RNA duplexes, BACE1-AS can regulate BACE1 indirectly by acting as a ceRNA. Therefore, we propose that BACE1 functions as a ceRNA and forms a network through its associations with protein-coding genes, lncRNAs and miRNAs in the pathophysiology of AD.

UMSC-derived exosomes promote retinal ganglion cells survival in a rat model of optic nerve crush.

Traumatic optic neuropathy or glaucoma lead to retinal ganglion cells loss and cause blindness, and there is no effective therapy strategy by far. Mesenchymal cells from the Wharton's jelly of the umbilical cord (umbilical cord mesenchymal stem cells, UMSCs) and UMSC-derived exosomes (UMSC-Exos) are promising candidates for allogeneic therapy in regenerative medicine, but their effort on optic nerve injury and the underlying mechanism remains undefined. In the present study, we investigated the functions of UMSC-Exos in a rat optic nerve crush (ONC) model. After three times of treatments with an interval of one week, we found that the UMSC-Exos significantly promoted Brn3a+ retinal ganglion cells (RGCs) survival in retinal ganglion cell layer compared with PBS controls. UMSC-Exos also significantly promoted GFAP+ glia cells activation in retina and optic nerve. However, no increase of GAP43+ axon counts in the optic nerve was found after UMSC-Exos treatment. Thus, our results demonstrate that UMSC-derived exosomes may play a role in neuroprotection by promoting the RGCs survival and glia cells activation but not the axon regeneration.

Effects of four disaccharides on nucleation and growth of ice crystals in concentrated glycerol aqueous solution.

Devitrification has been determined to be one of the major causes of cell death in cryopreservation by vitrification method. Reliable quantification of the nucleation and growth of ice crystals of devitrification is of great importance for the optimization of the vitrification solutions. In the present study, cryomicroscopy was used to investigate the nucleation and growth of ice crystals in concentrated glycerol aqueous solution (60 wt%) in the presence of sucrose, trehalose, maltose and lactose. Results showed that sucrose rather than trehalose seems to be the most effective one to inhibit the nucleation and ice growth, despite the excellent inhibitory ability of trehalose on ice growth that has been confirmed in many researches. Hence, for ice inhibition, sucrose was a more effective disaccharide additive to suppress nucleation and growth of ice crystals that occurred during devitrification in concentrated glycerol solutions.

Hybrid-functional calculations of electronic structure and phase stability of MO (M = Zn, Cd, Be, Mg, Ca, Sr, Ba) and related ternary alloy M x Zn1-x O.

Using the hybrid exchange-correlation functional within the density-functional theory, we have systematically investigated the structural and electronic properties of MO (M = Be, Mg, Ca, Sr, Ba, Zn, Cd) in binary rock salt (B1), zinc-blende (B3) and wurtzite (B4) phases, including the structural parameters, bulk moduli, band gaps and deformation potentials. Our results agree well with the experimental data and other theoretical results, and give a better understanding of the relationship between the geometric and electronic structure. After calculating the band alignment, we find that in both the B1 and B3 structures, the valence band maximum (VBM) has an obvious decrease from BeO to MgO to CaO, then it goes up from SrO to BaO to ZnO to CdO. Moreover, the properties of the ternary alloys M x Zn1-x O were studied through the application of the special quasi-random structure method. The critical value of the ZnO composition for the transition from the B3 structure to the B1 structure gradually increases from (Ca, Zn)O to (Mg, Zn)O to (Sr, Zn)O to (Ba, Zn)O to (Cd, Zn)O, indicating that (Ca, Zn)O can exist in the B3 structure with the lowest ZnO composition. These results provide a good guideline for the accessible phase space in these alloy systems.

Cell membrane permeability coefficients determined by single-step osmotic shift are not applicable for optimization of multi-step addition of cryoprotective agents: As revealed by HepG2 cells.

HepG2 cells have a number of research applications and cryopreservation of these cells would improve supply and thus facilitate the study. Development of effective cryopreservation protocols relies on knowledges of the fundamental mass transport characteristics of HepG2 cell membrane. Currently, the permeability parameters estimated from single-step addition are routinely used to predict the osmotic responses of the cells in multistep protocols, as well as used for prediction of optimal cooling rates. However, the reasonability of this approach has not been rigorously studied. Here we measured the hydraulic conductivity (Lp) and the permeability coefficient (Ps) of HepG2 cells in the absence/presence of dimethyl sulfoxide (Me2SO) at various temperatures with single and multistep addition of Me2SO. We found that the permeability yielded via one-step addition of the Me2SO cannot exactly predict the volume change of the cells when the CPA was added in multiple steps.

The measurement of lung volumes using body plethysmography and helium dilution methods in COPD patients: a correlation and diagnosis analysis.

Chronic obstructive pulmonary disease (COPD) is a chronic airway disease characterized by persistent airflow limitation. Moreover, lung hyperinflation evaluated by lung volumes is also the key pathophysiologic process during COPD progression. Nevertheless, there is still no preferred method to evaluate lung volumes. For this study, we recruited 170 patients with stable COPD to assess lung volumes stratified by airflow limitation severity. Lung volumes including residual volume (RV) and total lung capacity (TLC) were determined by both body plethysmography and helium dilution methods. The discrepancies between these two methods were recorded as ΔRV%pred, ΔTLC%pred, and ΔRV/TLC. We found that ΔRV%pred, ΔTLC%pred, and ΔRV/TLC increased significantly with the severity of COPD. The differences of lung capacity between these two methods were negatively correlated with FEV1%pred, and diffusing capacity for carbon monoxide (DLCO%pred). Moreover, the receiver operating characteristic (ROC) for ΔTLC%pred to distinguish severe COPD from non-severe COPD had an area under curve (AUC) of 0.886. The differences of lung volume parameters measured by body plethysmography and helium dilution methods were associated with airflow limitation and can effectively differentiate COPD severity, which may be a supportive method to assess the lung function of stable COPD patients.

Resolvin-D1 inhibits interleukin-8 and hydrogen peroxide production induced by cigarette smoke extract in 16HBE cells via attenuating NF-κB activation.

BACKGROUND: Cigarette smoke induced airway inflammation plays a role in pathogenesis of airway inflammation. Resolvin-D1 derived from omega-3 polyunsaturated fatty acids is an endogenous anti-inflammatory and proresolving lipid mediator. Resolvin-D1 ameliorated inflammatory responses in lung injury, asthma, peritonitis and atherosclerosis. We investigated whether resolvin-D1 suppressed the productions of chemokines and oxidative stress induced by cigarette smoke extract (CSE) in vitro and its possible mechanism. METHODS: We examined the proinflammatory chemokine interleukin-8 and hydrogen peroxide (H2O2) productions induced by CSE in 16 human bronchial epithelial (16HBE) cells after resolvin-D1 treatment and their mechanisms. 16HBE cells were treated with resolvin-D1 at up to 10 nmol/L, for 30 minutes before CSE up to 16% (v/v) exposure. Release of interlukin-8 proteins was assessed by enzyme linked immunosort assay (ELISA) and its mRNA level by RT-PCR. We evaluated extracellular H2O2 expression in the supernatant. Phosphorylation of NF-κB/p65 and degradation of I-κB in 16HBE cells were determined by Western blotting analysis and NF-κB DNA binding activity by electrophoretic mobility shift assay (EMSA). RESULTS: 16HBE cells treated with 8% CSE showed significantly higher interlukin-8 production. Resolvin-D1 pretreatment inhibited CSE induced interlukin-8 production (mRNA and protein) in a dose and time dependent manner. Extracellular H2O2 level decreased after resolvin-D1 treatment. Resolvin-D1 attenuated CSE triggered I-κB degradation and NF-κB/p65 activation dose dependently and inhibited NF-κB DNA binding activity. CONCLUSION: Resolvin-D1 inhibits CSE induced interlukin-8 and H2O2 production in 16HBE cells by modulating NF-κB activation and has therapeutic potential for pulmonary inflammation.

Increased expression of heat shock protein 70 in chronic obstructive pulmonary disease.

BACKGROUND: Heat shock protein 70 (HSP70) plays a critical role in the process of inflammation and innate immunity response under environmental stress. OBJECTIVES: This study was to investigate HSP70 expression in the peripheral lung tissues of chronic obstructive pulmonary disease (COPD) patients and in human bronchial epithelial cells (16-HBE) exposed to cigarette smoke extract (CSE). METHODS: Peripheral lung tissues were collected after lung cancer resection from 26 patients without COPD, 20 with mild COPD and 15 with advanced COPD, classified by lung function criteria. Among these cases, 37 were smokers and 24 non-smokers. Lung tissues were examined for histopathological changes and levels of HSP70 and IL-8. Cultured 16-HBE cells were stimulated with CSE in the absence or presence of HSP70 neutralizing antibody and the expressions of IL-8 and phospho-EGFR protein were determined. RESULTS: Compared to patients without COPD, the levels of HSP70 and IL-8 were significantly increased in the lung tissues of COPD patients and positively correlated with the severity of the disease. The HSP70 expression was significantly higher in current smokers than that in non-smokers. Moreover, CSE-induced HSP70 significantly enhanced IL-8 production and EGFR phosphorylation in 16-HBE cells. The increases in IL-8 and phospho-EGFR were blocked by anti-HSP70 antibody. CONCLUSIONS: Our study clarified that increased expression of HSP70 is closely related to COPD disease severity and smoking status. Extracellular HSP70 regulated chemokine productions and EGFR phosphorylation and plays an important role in the CSE-induced inflammatory and innate immunity responses in bronchial epithelia cells.

A vacuolar processing enzyme RsVPE1 gene of radish is involved in floral bud abortion under heat stress.

Radish floral bud abortion (FBA) is an adverse biological phenomenon that occurs during reproduction. Although FBA is a frequent occurrence, its molecular mechanism remains unknown. A transcript-derived fragment (TDF72), which was obtained by cDNA amplified fragment length polymorphism (cDNA-AFLP), was up-regulated in the aborted buds and exhibited 89% sequence homology with the AtγVPE gene. In this study, TDF72 was used to clarify the role of VPE in FBA by isolation of the VPE gene RsVPE1 from radish flower buds. The full-length genomic DNA was 2346 bp including nine exons and eight introns. The full-length cDNA was 1825 bp, containing a complete open reading frame (ORF) of 1470 bp, which encoded a predicted protein containing 489 amino acid residues, with a calculated molecular mass of 53.735 kDa. Expression analysis demonstrated that RsVPE1 was expressed in all tested organs of radish at different levels. Highest expression was detected in aborted flower buds, suggesting that RsVPE1 has a role in FBA. In order to analyze the role of RsVPE1 in FBA, RsVPE1 was overexpressed in transgenic Arabidopsis thaliana plants. Aborted flower buds appeared in transgenic plants subjected to heat stress. In addition, RsVPE1 expression in the transgenic plants reached a maximum when subjected to heat stress for 24 h and increased by 2.1-fold to 2.8-fold in three homozygous transgenic lines. These results indicated that RsVPE1 led to FBA when its expression levels exceeded a particular threshold, and provided evidence for the involvement of RsVPE1 in promoting FBA under heat stress.

Role of extracellular signal-regulated kinase 1/2 in cigarette smoke-induced mucus hypersecretion in a rat model.

BACKGROUND: Airway mucus hypersecretion is an important pathophysiological feature of chronic obstructive pulmonary disease, which is closely associated with cigarette smoking. However, the signal transduction pathway from the cell surface to the nucleus through which cigarette smoke causes upregulation of mucin gene expression is not well known. This study was designed to investigate the role of extracellular signal-regulated Kinase 1/2 (ERK 1/2) in airway mucus hypersecretion induced by cigarette smoke in rats. METHODS: A rat model of airway mucus hypersecretion was induced by exposure to cigarette smoke for 4 weeks.Rats exposed to inhalation of cigarette smoke or normal saline were given an intraperitoneal injection of U0126, a specific MEK1 kinase inhibitor, at doses of 0.25 mg/kg, 0.5 mg/kg and 1 mg/kg for 14 days. Expression of MUC5AC mRNA and protein, ERK 1/2 and phosphorylated-ERK 1/2 (p-ERK 1/2) were detected by RT-PCR, immunohistochemistry and Western blotting. RESULTS: Cigarette smoke significantly increased airway goblet cells metaplasia, induced the overexpression of MUC5AC mRNA and protein in bronchial epithelia, and increased the ratio of p-ERK 1/2 and ERK 1/2. U0126 significantly attentuated the expression of MUC5AC mRNA and protein induced by cigarette smoke (P < 0.05). Moreover, there was a significant positive correlation between the ratio of p-ERK1/2 to ERK1/2 and the expression of MUC5AC mRNA and protein (P < 0.05). CONCLUSIONS: Inhibition of ERK 1/2 by U0126 decreased the ratio of p-ERK 1/2 to ERK 1/2 and expression of MUC5AC mRNA and protein. ERK 1/2 may play an essential role in cigarette smoke-induced mucus hypersecretion in vivo.

[Association between interleukin-8 in lung tissues and stages of chronic obstructive pulmonary diseases].

OBJECTIVE: To investigate the expression of interleukin (IL)-8 in lung tissues from patients with chronic obstructive pulmonary disease (COPD) and its association with stages of COPD. METHODS: The levels of mRNA and protein of IL-8 were measured with semi-quantitative polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) in patients with mild COPD (n=21), patients with advanced COPD (n=15), and controls (n=15). The correlations between IL-8 levels and stages of COPD, lung function (FEV1/ FVC%, FEV1% pred) and cigarette smoking were analyzed with Pearson correlation analysis. RESULTS: The levels of IL-8 mRNA and protein in the lung tissues of COPD patients were significantly higher than those in the control group (P<0.05). The patients with advanced COPD had higher levels of IL-8 mRNA and protein than the patients with mild COPD (P<0.05). The COPD patients who smoked had higher levels of IL-8 mRNA and protein than those who did not smoke (P<0.05). But no significant differences in the levels of IL-8 mRNA and protein were found between smokers and and nonsmokers who did not have COPD (P>0.05). Increased expression of IL-8 in patients with COPD was positively correlated with stages of COPD (r=0.81, P<0.05); negatively correlated with lung function (FEV1/FVC%, FEV1% pred) (r=-0.62, -0.56, P<0.05), and positively correlated with volumes of cigarette smoking (r=0.53, P<0.05). CONCLUSION: IL-8 is associated with stages of COPD, which may serve as an indication for clinical progress. Cigarette smoking increases IL-8 expression in the lung tissues of COPD patients.

[RNA fingerprinting of the differential expression fragments related to cytoplasmic male sterility in Chinese cabbage].

In order to investigate the differential expression of the genes related to cytoplasmic male sterility in Chinese cabbage (Brassica campestris L. ssp. Penkinsis), a modified RNA fingerprinting technique was developed to compare the difference in the total RNA from flower bud of Chinese cabbage among cytoplasmic male sterility (CMS) lines, maintainer lines and F1 hybrids. Four stably differential fragments S47-412, S93-622, S176-343 and S199-904 were amplified, cloned and sequenced with primers selected from 186 random primers. Based on the nucleotide sequence of the four differential fragments, four pairs of specific primers were designed to validate the differential fragments. The validation showed S47-412 and S93-622 were false positives and S176-343 and S199-904 were confirmed by PCR with the specific primers. Sequence analysis revealed that both of two differential fragments had strong homology with the nucleotide sequence of orf224/atp6 site of Polima CMS and the nucleotide sequence of S176-343 and S199-904 had a superposed region. All these indicate that the two fragments probably have strong relationship with cytoplasmic male sterility in Chinese cabbage.