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It has been suggested that a trade-off between hydraulic efficiency and safety is related to drought adaptation across species. However, whether leaf hydraulic efficiency is sacrificed for safety during woody resprout regrowth after crown removal is not well understood. We measured leaf water potential (ψleaf ) at predawn (ψpd ) and midday (ψmid ), leaf maximum hydraulic conductance (Kleaf-max ), ψleaf at induction 50% loss of Kleaf-max (Kleaf P50 ), leaf area-specific whole-plant hydraulic conductance (LSC), leaf vein structure and turgor loss point (πtlp ) in 1- to 13-year-old resprouts of the aridland shrub (Caragana korshinskii). ψpd was similar, ψmid and Kleaf P50 became more negative, and Kleaf-max decreased in resprouts with the increasing age; thus, leaf hydraulic efficiency clearly traded off against safety. The difference between ψmid and Kleaf P50 , leaf hydraulic safety margin, increased gradually with increasing resprout age. More negative ψmid and Kleaf P50 were closely related to decreasing LSC and more negative πtlp , respectively, and the decreasing Kleaf-max arose from the lower minor vein density and the narrower midrib xylem vessels. Our results showed that a clear trade-off between leaf hydraulic efficiency and safety helps C. korshinskii resprouts adapt to increasing water stress as they approach final size.

Plants control water-use efficiency (WUE) by regulating water loss and CO2 diffusion through stomata. Variation in stomatal control has been reported among lineages of vascular plants, thus giving rise to the possibility that different lineages may show distinct WUE dynamics in response to water stress. Here, we compared the response of gas exchange to decreasing leaf water potential among four ferns and nine seed plant species exposed to a gradually intensifying water deficit. The data collected were combined with those from 339 phylogenetically diverse species obtained from previous studies. In well-watered angiosperms, the maximum stomatal conductance was high and greater than that required for maximum WUE, but drought stress caused a rapid reduction in stomatal conductance and an increase in WUE in response to elevated concentrations of abscisic acid. However, in ferns, stomata did not open beyond the optimum point corresponding to maximum WUE and actually exhibited a steady WUE in response to dehydration. Thus, seed plants showed improved photosynthetic WUE under water stress. The ability of seed plants to increase WUE could provide them with an advantage over ferns under drought conditions, thereby presumably increasing their fitness under selection pressure by drought.

OBJECTIVES/HYPOTHESIS The routine practices of examining submucosal lesions are not suitable for deep lesions. Therefore, we evaluated the efficacy of non-real-time image-guided transnasal endoscopic fine-needle aspiration biopsy (FNAB) in diagnosing nasopharyngeal carcinoma (NPC) with submucosal lesions. STUDY DESIGN The effectiveness evaluation of diagnostic methods. METHODS Fifty suspected NPC patients who failed in conventional biopsies were enrolled in this study. The efficacy, maneuverability, and safety of FNAB in diagnosing these intractable cases were evaluated. RESULTS The definitive diagnostic results of these 50 patients were NPC (34/50, 68.0%), nasopharyngeal necrosis (1/50, 2.0%), nasopharyngeal mucositis (12/50, 24.0%), and other cancers (3/50, 6.0%), respectively. The results of the diagnostic efficacy of FNAB were sensitivity, 89.2%; specificity, 100.0%; positive predictive value, 100.0%; negative predictive value, 76.5%; and accuracy, 92.0%, respectively. The area under the receiver operating characteristic curves was 0.946 (95% confidence interval = 0.884-1.00, P

BACKGROUND Topical anesthesia is widely used in many dermatological and cosmetic procedures. Nevertheless, the stratum corneum serves as the skin barrier, impedes the transdermal drug delivery greatly, and results in insufficient analgesia. Cold atmospheric plasma (CAP) has been researched as a transdermal drug delivery promoter with ex vivo experiments for a few years, while clinical trials are scarce. AIMS To assess the efficacy and safety of CAP as a pretreatment to improve the transdermal absorption of topical anesthetic cream before the CO2 laser treatment for postacne scars in the human body. PATIENTS/METHODS Twenty patients, seeking full facial laser treatment for atrophic acne scars, underwent a randomized split-face study. One side of the face was pretreated by CAP before topical anesthetic cream was applied, and the other side was applied with topical anesthetic cream only as control. After that, the subjects went through full-face fractional CO2 laser treatment of postacne scars. They were asked to score the pain on a visual analogue scale (VAS) after the laser treatment to measure the anesthesia effects which indicates the transdermal absorption of the cream. Possible adverse effects of the plasma were recorded during the pretreatment including associated pain, heat, erythema, and edema. RESULTS The VAS score of the treated side was statistically lower (5.1 ± 2.1) compared with the nontreated side (6.3 ± 1.9), with a mean difference of 1.3 (95% confidence interval [CI], 0.6-1.9; P

Investigating plant morphological traits can provide insights into plant drought tolerance. To date, many papers have focused on plant hydraulic responses to drought during dehydration, but atmospheric water absorption by trichomes to mitigate drought stress by influencing leaf hydraulics in plant species that inhabit arid environments has been largely ignored. The experiment in this study was designed to assess how dew absorbed by leaf trichomes helps Caragana korshinskii withstand drought. The results showed that under a drought stress and dew (DS & D) treatment, C. korshinskii displayed a strong capacity to absorb dew with trichomes; exhibited slow decreases in leaf water potential (Ψleaf ), leaf hydraulic conductivity (Kleaf ), and gas exchange; experienced 50% Kleaf and gas exchange losses at lower relative soil water content levels than plants treated with drought stress and no dew (DS & ND); and experienced 50% Kleaf loss (Kleaf P50 ) at similar Ψleaf levels as DS & ND plants. Its congener C. sinica, which does not have leaf trichomes, displayed little ability to absorb dew under drought stress and did not show any remarkable improvement in the above parameters under the DS & D treatment. Our results indicated that leaf trichomes are important epidermal dew-uptake structures that assist in partially sustaining the leaf hydraulic assimilation system, mitigate the adverse effects of drought stress and contribute to the distribution of C. korshinskii in arid environments.

Drought is a cyclical phenomenon in natural environments. During dehydration, stomatal closure is mainly regulated by abscisic acid (ABA) dynamics that limit transpiration in seed plants, but following rehydration, the mechanism of gas exchange recovery is still not clear. In this study, leaf water potential (ψleaf ), stomatal conductance (gs ), leaf hydraulic conductance (Kleaf ), foliar ABA level, ethylene emission rate in response to dehydration and rehydration were investigated in four Caragana species with isohydric (Caragana spinosa and C. pruinosa) and anisohydric (C. intermedia and C. microphylla) traits. Two isohydric species with ABA-induced stomatal closure exhibited more sensitive gs and Kleaf to decreasing ψleaf than two anisohydric species which exhibited a switch from ABA to water potential-driven stomatal closure during dehydration. Following rehydration, the recovery of gas exchange was not associated with a decrease in ABA level but was strongly limited by the degradation of the ethylene emission rate in all species. Furthermore, two anisohydric species with low drought-induced ethylene production exhibited more rapid recovery in gas exchange upon rehydration. Our results indicated that ethylene is a key factor regulating the drought-recovery ability in terms of gas exchange, which may shape species adaptation to drought and potential species distribution.

Use of genetically engineered plants that express insecticidal Cry proteins derived from Bacillus thuringiensis (Bt) have been proven efficacious for managing lepidopteran pests. However, in some cases herbivores that are not targeted by the Bt trait have increased in importance. It has been suggested that reduced caterpillar damage to Bt crops could lead to decreased levels of induced plant defensive compounds which might benefit other non-target herbivores. Here we investigated the potential effect of reduced damage by larvae of Mythimna separata on aphid populations in Bt corn. We compared the performance of Rhopalosiphum maidis feeding on non-Bt corn plants that had been infested by M. separata larvae or were uninfested. The results showed that caterpillar-infested corn plants significantly reduced the fitness of R. maidis leading to a prolonged nymphal development time, reduced adult longevity and fecundity compared to uninfested plants. Consequently, the population growth rate of corn aphids feeding on caterpillar-infested corn plants was significantly lower than on uninfested plants. As expected, the aphids performed significantly better on Lepidoptera-resistant Bt corn than on non-Bt corn when plants were infested with M. separata, since the caterpillars caused very little damage to the Bt plants. The current findings indicate that reduced M. separata infestation could benefit aphid development in Bt corn. Bt corn has the potential to be commercialized in China in the near future and aphids and other non-target pests should be monitored in the farming fields.

The polypnictide complexes of rare earth cations have drawn the attention of the scientific community for their uncommon bonding modes and potential applications. Herein, we present a systematic and comprehensive summary on recent advances in the field of rare earth polypnictides, focusing on their synthesis, structures, and reactivities. The structural stabilizing effects imposed by the electropositive rare earth cations as well as the reducing capability of rare earth precursors in the synthesis of these polypnictide complexes are described in this review. We also disscuss in detail the bonding interactions and coordination modes between rare earth cations and polypnictide clusters as well as the similarities and the peculiarity of some structures.

The chemical bonding of Zintl clusters is still an evolving and hot topic in modern chemistry. In this paper we synthesized a novel [K([2.2.2]crypt)]4 [In8 Bi13 ] complex in a condensed phase. The quantum chemical calculations and X-ray data revealed that the compound consists of the 1:1 mixture of [Bi@In8 Bi12 ]3- and [Bi@In8 Bi12 ]5- clusters. To the date, those clusters are the largest binary clusters composed of In and Bi elements. Herein, we introduce a spherical aromatic description of chemical bonding for such clusters. We show through AdNDP, ELF, and induced magnetic field and quantitative NICS analyzes that both clusters are spherically aromatic which explains their high symmetry, stability, and peculiar magnetic properties. We believe that this work will help researchers in the further development and understanding of chemical bonding in Zintl clusters.

Background Riehl's melanosis is a chronic, refractory disorder, which can adversely affect patient's quality of life. Intense pulse light, neodymium-doped yttrium aluminum garnet laser, hydroquinone, tranexamic acid have been reported to treat this disease, but there have been few reports on the effectiveness of other treatments. Aim To assess the efficacy and safety of triple combination therapy with salicylic acid chemical peels, oral glycyrrhizin compound, and vitamin C for Riehl's melanosis. Patients/methods Three patients diagnosed with Riehl's melanosis were enrolled. All patients were treated with glycyrrhizin compound (150 mg/d), vitamin C (100 mg/d), and salicylic acid 30% peels once every 2 weeks. Clinical photographs and VISIA were used to assess the efficacy. Results All patients received obvious improvement and reported no obvious side effects. Conclusion Triple combination therapy with salicylic acid peels, oral glycyrrhizin compound, and vitamin C is a safe and effective modality for Riehl's melanosis.

Background Acaricide resistance is a serious problem in spider mites. Cyflumetofen is a new complex II inhibitor, whereas pyridaben acts at complex I and has been used for decades. Although cross-resistance between cyflumetofen and pyridaben has been observed in Tetranychus cinnabarinus, the specific mechanisms at play have not yet been investigated. Results Investigation into the cross-resistance mechanisms identified five P450s, among which CYP389C16 was evaluated as the most likely candidate conferring cross-resistance. Knockdown of CYP389C16 expression via RNA interference diminished the level of cross-resistance in the cyflumetofen-resistant strain. In addition, recombinant CYP389C16 (40 pmol) effectively metabolized 25.0 ± 0.7% of cyflumetofen, 39.7 ± 1.0% of pyridaben, and 69.3 ± 3.3% of AB-1 (active de-esterified metabolite of cyflumetofen) within 2 h. In addition, hydroxylation metabolite of AB-1 was identified by HPLC-MS/MS. Conclusions The study reveals that overexpressed CYP389C16 is involved in the cross-resistance between cyflumetofen and pyridaben in T. cinnabarinus. © 2019 Society of Chemical Industry.

Background Cyflumetofen is an outstanding acaricide with a novel mode of action. Tetranychus cinnabarinus, an important agricultural pest, is notorious for developing resistance to most classes of acaricides rapidly and results in enormous loss for the economy. Our previous study had pointed out glutathione S-transferase (GSTs) significantly contributed to the cyflumetofen-resistance formation in T. cinnabarinus, but the more specific mechanism needed to be further investigated. Results The unstable resistance was observed in cyflumetofen-resistant strain (CyR)under acaricide-free condition. The activity of GSTs increased along with the development of resistance. The expressions of 13 GST genes were detected in CyR and susceptible strain (SS), of which six genes were overexpressed in CyR and the TcGSTm02 was selected as the representative for functional study. The expression of TcGSTm02 changed along with the resistant level of CyR with the same trend. Recombinant protein of TcGSTm02 with high activity was successfully obtained by E. coli expression system, whose activity could be inhibited by cyflumetofen (IC50 = 0.23 mM). Recombinant TcGSTm02 could effectively decompose cyflumetofen, and catalyze GS- to conjugate with cyflumetofen. Conclusion All clues confirmed that GSTs strongly associated with cyflumetofen-resistance and a representative gene, TcGSTm02, showed function on contributing the evolution of cyflumetofen-resistance in T. cinnabarinus. © 2019 Society of Chemical Industry.

Two series of isostructural lanthanide coordination complexes, namely, LIFM-42(Ln) (Ln=Eu, Tb, Gd, in which LIFM stands for the Lehn Institute of Functional Materials) and LIFM-43(Ln) (Ln=Er, Yb), were synthesized through the self-assembly of an excited-state intramolecular proton transfer (ESIPT) ligand, 5-[2-(5-fluoro-2-hydroxyphenyl)-4,5-bis(4-fluorophenyl)-1H-imidazol-1-yl]isophthalic acid (H2 hpi2cf), with different lanthanide ions. In the coordination structures linked by the ligands and oxo-bridged LnIII2 clusters (for LIFM-42(Ln) series) or isolated LnIII ions (for LIFM-43(Ln) series), the ESIPT ligand can serve as both the host and antenna for protecting and sensitizing the photoluminescence (PL) of LnIII ions. Meanwhile, the -OH⋅⋅⋅N active sites on the ligands are vacant, which provides availability to systematically explore the PL behavior of Ln complexes with ESIPT interference. Based on the accepting levels of different lanthanide ions, energy transfer can occur from the T1 (K*) or T1 (E*) (K*=excited keto form, E*=excited enol form) excited states of the ligand. Furthermore, the sensitized lanthanide luminescence in both visible and near-infrared regions, as well as the remaining K* emission of the ligand, can be modulated by the ESIPT responsiveness to different solvents, anions, and temperature.

Colon cancer is the third most common malignancy and one of the leading causes of cancer-associated mortality worldwide. Neuronal pentraxin 1 (NPTX1) is associated with tumor progression in some types of tumors. However, its expression and role in colon cancer has not been yet reported. Here we observed that NPTX1 was down-regulated in colon cancer. Additionally, we explored the functional significance of NPTX1 in colon cancer. We found that over-expression of NPTX1 inhibited colon cancer cell growth by performing MTT, colony formation, Edu corporation assays, and cell cycle analysis. In vivo mouse experiments also confirmed the anti-proliferative role of NPTX1 in colon cancer. Further mechanistic study showed that over-expression of NPTX1 inhibited the expression of cyclin A2 and CDK2 in colon cancer cells, thereby regulating the Rb-E2F signaling. In summary, these findings reveal that NPTX1 suppress the colon cancer cell growth and might serve as a useful potential target for treatment of colon cancer.

In past decades, increasing evidence regarding cancer stem cells (CSCs) may account for carcinogenesis, tumor drug-resistant, and metastasis. CSCs are even considered as the root causes of tumor recurrence and metastases. Targeting CSCs may provide a new clue to cure cancer. Epidemiological and clinical studies have suggested that intake of dietary natural products may bring health benefits including lowering risk of cancer incidence. In this review, we have particularly focused on targeting signaling pathways of CSCs by natural resveratrol and its dimethylated derivative pterostilbene. © 2017 BioFactors, 44(1):61-68, 2018.

Background and Purpose Mirabegron has been classified as a β3-adrenoceptor agonist approved for overactive bladder syndrome. We investigated possible cardiac effects of mirabegron in the absence or presence of β-adrenoceptor subtype antagonists. In view of its phenylethanolamine structure, we investigated whether mirabegron has indirect sympathomimetic activity by using neuronal uptake blockers. Experimental Approach Right atrial trabeculae, from non-failing hearts, were paced and contractile force measured at 37°C. Single concentrations of mirabegron were added in the absence or presence of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), β3 (L-748,337), β1 (CGP 20712A), β2 (ICI 118,551) -adrenoceptor antagonists, neuronal uptake inhibitors desipramine or phenoxybenzamine. Key Results Mirabegron significantly increased contractile force in human right atrium (1 μM, 7.6 ± 2.6%, n = 7; 10 μM, 10.2 ± 1.5%, n = 22 compared with (−)-isoprenaline P

A new approach to functionalized γ-butenolides based on reagent-controlled tandem reaction sequences of Morita–Baylis–Hillman-type vinyl epoxides is described. The nucleophilic addition of a tertiary phosphine to the electron-deficient alkene led to ring-opening of the epoxide followed by lactonization to produce phosphonium ylides, which could undergo Wittig olefination with aryl trifluoromethyl ketones and aryl aldehydes to give 3-alkenyl γ-butenolides in moderate to good yields and high E/Z selectivity. Tertiary amine promoted the Michael-type addition of carbon- and nitrogen-based nucleophiles to the vinyl epoxides followed by lactonization to provide diverse 3-substituted γ-butenolides.

Two new secolignans, peperomins G and H (1 and 2, resp.), were isolated from the whole plant of Peperomia dindygulensis, together with five known secolignans, peperomin A (3), peperomin E (4), peperomin B (5), 2,3-trans-2-methyl-3-{(3-hydroxy-4,5-dimethoxyphenyl)[5-methoxy-3,4-(methylenedioxy)phenyl]methyl}butyrolactone (6), 2,3-cis-2-(hydroxymethyl)-3-{bis[5-methoxy-3,4-(methylenedioxy)phenyl]methyl}butyrolactone (7). Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR techniques. Antiangiogenic effects of all compounds were evaluated using human umbilical vein endothelial cells (HUVEC) proliferation and tube-formation tests, with compounds 4 and 5 being active in the bioassay. Compounds 4 and 5 induced obvious cell toxicity to HUVEC with IC(50) values of 1.64±0.19 and 8.44±0.4 μM, respectively. Compounds 4 and 5 also exhibited significant HUVEC tube formation-inhibiting activity with IC(50) values of 3.13±0.09 and 6.24±0.12 μM, respectively.

Different defense mechanisms of three spring wheat (Triticum aestivum L.) varieties were studied by withholding watering in well-watered pots to gradually increase water deficit of plants grown in containers. The strategies of plant adaptation were divided into three phases according to the severity of drought: first, a positive defense phase that started from commencement of non-hydraulic root-sourced signals (nHRS) and ended at onset of hydraulic root-sourced signals (HRS)--the plant responded to imminent drought by decreasing stomatal aperture to lessen water loss and no membrane injury occurred. The second defense phase occurred between the onset of HRS and temporary wilting (TW), characterized by enhancement of reactive oxygen species (ROS), marked enzyme activity and increased MDA content. Mild lipid membrane peroxidation came mainly from a dynamic imbalance between free radical production and enzymatic defense reaction, which indicated that injury by ROS had not been completely repaired by increasing enzymatic activity. The third defense phase was from TW to permanent wilting (PW), the synthesis of SOD and CAT during TW could not deal with the collapse of antioxidant enzymes, and SOD and CAT activities began to decrease, which caused the excessive ROS production and thus serious membrane lipid peroxidation. The defense strategies to drought are similar among the varieties, but modern varieties LC8275 and GY602 bred after 1975 had relatively higher defense levels at all three defense phases, which suggest that modern varieties are more resistant than old ones, and artificial selection would lead to a different direction in evolution from natural selection.

In search of novel anticancer agents, two series of dimethyl [1,1'-biphenyl]-2,2'-dicarboxylate derivatives, 8a-8k and 9a-9k, containing both methylenedioxy and 1,3,4-thiadiazole moieties were designed and synthesized. Cytotoxicity of these compounds was evaluated in vitro against five human tumor cell lines, i.e., HepG2, KB, A549, K562, and MCF-7. The results indicated that 8h, 8j, 8k, 9d, 9g, 9h, 9j, and 9k showed notable anticancer activities comparable to or stronger than that of 5-fluorouracil, a canonical anticancer drug. Structure-activity relationships were also discussed based on the experimental data obtained.

The self-thinning rule defines a straight upper boundary line on log-log scales for all possible combinations of mean individual biomass and density in plant populations. Recently, the traditional slope of the upper boundary line, -3/2, has been challenged by -4/3 which is deduced from some new mechanical theories, like the metabolic theory. More experimental or field studies should be carried out to identify the more accurate self-thinning exponent. But it's hard to obtain the accurate self-thinning exponent by fitting to data points directly because of the intrinsic problem of subjectivity in data selection. The virtual dynamic thinning line is derived from the competition-density (C-D) effect as the initial density tends to be positive infinity, avoiding the data selection process. The purpose of this study was to study the relationship between the virtual dynamic thinning line and the upper boundary line in simulated plant stands. Our research showed that the upper boundary line and the virtual dynamic thinning line were both straight lines on log-log scales. The slopes were almost the same value with only a very little difference of 0.059, and the intercept of the upper boundary line was a little larger than that of the virtual dynamic thinning line. As initial size and spatial distribution patterns became more uniform, the virtual dynamic thinning line was more similar to the upper boundary line. This implies that, given appropriate parameters, the virtual dynamic thinning line may be used as the upper boundary line in simulated plant stands.