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A variety of complex socioeconomic phenomena, for example, migration, commuting, and trade can be abstracted by spatial interaction networks, where nodes represent geographic locations and weighted edges convey the interaction and its strength. However, obtaining fine-grained spatial interaction data is very challenging in practice due to limitations in collection methods and costs, so spatial interaction data such as transportation data and trade data are often only available at a coarse scale. Here, we propose a gravity downscaling (GD) method based on readily accessible socioeconomic data and the gravity law to infer fine-grained interactions from coarse-grained data. GD assumes that interactions of different spatial scales are governed by the similar gravity law and thus can transfer the parameters estimated from coarse-grained regions to fine-grained regions. Results show that GD has an average improvement of 24.6% in Mean Absolute Percentage Error over alternative downscaling methods (i.e., the areal-weighted method and machine learning models) across datasets with different spatial scales and in various regions. Using simple assumptions, GD enables accurate downscaling of spatial interactions, making it applicable to a wide range of fields, including human mobility, transportation, and trade. [ABSTRACT FROM AUTHOR]

Background: Transparency in physician billing practices in the United States is lacking. Often, charges may vary substantially between providers and excess charges may be passed on to the patient. In this study, we evaluate Medicare charges and payments for minimally invasive lobectomy to obtain a sense of national billing practices and evaluate for predictors of higher charges. Methods: The 2018 Medicare Provider Utilization Data was queried to identify surgeons submitting charges for Video-Assisted Thoracoscopic Lobectomy. Excess charges were determined by each provider. Additional demographic variables were collected including geographic region for general surgery and cardiothoracic surgery training, years in practice, and current practice setting. A multivariate gamma regression was utilized to determine predictors of high billing practices. Results: A total of 307 unique providers submitted charges ranging from $1,104 to $25,128 with a median of $4,265. The average Medicare Payment amount ranged from $163 to $1,409, with a median of $1,056. Male surgeons were estimated to charge 1.3 times more than female surgeons, while those in an academic setting were estimated to charge 1.4 times more than private practice (p < 0.01). Surgeons practicing in the South or West were estimated to charge 0.76 and 0.81 times as much as those practicing in the Northeast (p < 0.01). Conclusions: Billing practices vary widely across the United States. Charges submitted to Medicare likely represent a provider's charges across all payers. In today's healthcare economy, it is important for patients to understand the true cost of care and for providers to be mindful of reasonable and appropriate charges. [ABSTRACT FROM AUTHOR]

Skin cancer has become increasingly common among young adults; however, this population does not consistently adhere to recommended methods for preventing the disease. Interventions in college settings have relied on appearance-focused appeals and have not been able to examine the cumulative effect of multiple behavior change and skin cancer risk communication strategies. The goal of the current study was to examine the unique and combined impacts of personalized ultraviolet (UV) radiation photographs, genetic testing for skin cancer risk, and general skin cancer prevention education. Participants were randomly assigned to one of four conditions: (1) skin cancer prevention education, (2) education + UV photo, (3) education + genetic testing, and (4) education + UV photo + genetic testing. Self-reported sun protection, tanning, and sunburn were assessed at baseline, immediately post-intervention, and 1 month post-intervention. The findings indicated benefits of the interventions to skin cancer prevention behaviors in the overall sample; however, the combined (UV photo + genetic testing) intervention had the most consistent positive effects on behaviors. Intervention effects were distinct across seasons. These results suggest that interventions containing multiple skin cancer risk communication strategies hold promise in benefitting health-promoting behavior changes in an at-risk, young adult population. Trial Registration Number: NCT03979872; Registered 6/5/2019. [ABSTRACT FROM AUTHOR]

We developed an effective and specific colorimetric strategy to detect Salmonella typhimurium (S. typhimurium) based on hexadecyl trimethyl ammonium bromide (CTAB)-induced supramolecular assembly of β-cyclodextrin-capped gold nanoparticles (β-CD-AuNPs). In this study, ssDNA aptamer of S. typhimurium could combine with CTAB to form the supramolecular ssDNA-CTAB composite, so the ssDNA aptamer was applied to control the concentration of CTAB. In the presence of S. typhimurium, ssDNA aptamers selectively bound to S. typhimurium but not to CTAB, leading to the host–guest chemistry reaction of CTAB and β-CD resulting in β-CD-AuNP supramolecular assembly aggregation with an obvious color change. The ratio of absorption at 650 and 520 nm (A650nm/A520nm) has a linear correlation to the log scale of the concentration of the bacteria (1 × 102–1 × 107 CFU/mL) with a low limit of detection (LOD) of 13 CFU/mL. In addition, this optical sensor has good selectivity and practicability. In milk samples, the recovery was 93.55–111.32%, which suggested its potential application in real samples. [ABSTRACT FROM AUTHOR]

As shown in studies conducted in recent decades, polyoxometalates (POMs), as inorganic metal oxides, have promising biological activities, including antitumor, anti-infectious and anti-Alzheimer's activities, due to their special structures and properties. However, some side effects impede their clinical applications to a certain extent. Compared with unmodified POMs, POM-based inorganic–organic hybrids and POM-based nanocomposite structures show significantly enhanced bioactivity and reduced side effects. In this review, we introduce the biological activities of POMs and their derivatives and highlight the side effects of POMs on normal cells and organisms and their possible mechanisms of action. We then propose a development direction for overcoming their side effects. POMs are expected to constitute a new generation of inorganic metal drugs for the treatment of cancer, infectious diseases, and Alzheimer's disease. Graphical abstract [ABSTRACT FROM AUTHOR]

Staphylococcus aureus (S. aureus) is a pathogen closely associated with foodborne diseases. We prepared a reliable colorimetric sensor to detect S. aureus using click chemical reaction and immunomagnetic separation. Aptamer-functionalized and ALP-labeled Fe3O4 NPs act as separation and signal transduction elements. Under the optimized conditions, the Cu+ generated by signal transduction triggers a click chemistry reaction, which causes the aggregation of azides and alkyne-AuNPs and a color change. The net extinction ratio of Δ(A530/A760) was linearly correlated with the S. aureus concentration from 10 to 106 cfu mL−1, and the limit detection was 2.4 cfu mL−1. The recoveries were 91.15 ~ 106.36% for the analysis of spiked food and water samples without pre-enrichment. Therefore, we believe that the detection platform can be easily and accurately used for S. aureus detection, providing a broad prospect for on-site visual detection. [ABSTRACT FROM AUTHOR]

In situ flushing through surfactant-enhanced aquifer remediation (SEAR) technology has long been recognized as a promising technique for NAPL removal from contaminated aquifers. However, there have been few studies on the choice of surfactants. In this work, the interaction quantitative model between resonance light scattering intensity and the concentration of binary surfactant mixtures NP-10+SDBS and NP-10+CTAB was established, and the mechanism of binary surfactant interaction was explored through the model by the resonance light scattering method. The relationship between the model constants and NAPL solubilization was also investigated to better address the application of surfactants in practical NAPL-contaminated site remediation. The critical micelle concentrations (CMCs) of nonylphenol ethoxylate (NP-10), dodecyl benzene sulfonate (SDBS), hexadecyl trimethyl ammonium bromide (CTAB), and the binary surfactant mixtures were measured by resonance light scattering (RLS), which were consistent with those obtained from surface tension measurements. In all cases, the RLS signals exhibited similar variations with surfactant concentration. A quantitative calculation model based on the RLS measurement data was established, and the binding constants KNP-10+SDBS and KNP-10+CTAB were calculated to be 0.66 and 1.51 L·mmol−1, respectively, according to the equilibrium equations. The results showed that the binding constants have a significant positive correlation with NAPL solubilization. [ABSTRACT FROM AUTHOR]

A host–guest colorimetric strategy is described for the detection of Listeria monocytogenes (L. monocytogenes). The optical probes were self-assembled based on the supramolecular interactions between the carbonyl groups of cucurbit[7]uril portals and gold nanoparticles (CB[7]-AuNPs). Aptamer and urease modified magnetic nanoparticles were used to specifically recognize and binding to L. monocytogenes, simultaneously hydrolyzing urea to produce ammonium ion (NH4+) that can reverse CB[7] induced AuNPs aggregation. In the presence of L. monocytogenes, the above-mentioned magnetic conjugates preferentially bind to the bacterial surface, which results in blocking the catalytic active sites, thus inhibiting the production of ammonium ions. The normalized absorbance ratio of A700 nm/A525 nm was proportional to the L. monocytogenes concentration ranging from 10 to 106 cfu·mL−1, and the visual determination can be done down to 10 cfu·mL−1. For spiked food samples analyzed without pre-enrichment, recoveries of 98.4% to 99.3% were achieved could be verified and RSD were less than 10%. This work may offer a broad prospect for sensitive and specific determination of pathogens. [ABSTRACT FROM AUTHOR]

Purpose: To examine patterns of radiotherapy (RT) and endocrine therapy (ET) use, associations between RT omission and ET adherence, and associations among ET and RT use and disease recurrence in older women with early-stage, estrogen receptor-positive breast cancer. Methods: Women age 65 and older diagnosed with hormone receptor-positive, clinically node-negative breast cancer between 2005 and 2018 and who did not undergo mastectomy were included. Multinomial logistic regression was used to examine the trends in practice patterns over time and by age. Kaplan–Meier estimates were used to estimate the probability of ET discontinuation. Cox proportional hazards models were constructed to assess associations between recurrence and ET/RT. Results: Of the 484 enrolled patients, 47.9% patients underwent RT and initiated ET, 27.4% received ET alone, 10.2% received RT alone, and 13.8% patients received neither. Older patients had a higher probability of receiving ET alone or neither ET nor RT (both p < 0.001). The probability of initiating ET was greater among patients who underwent RT than those who omitted RT (p < 0.001). Regardless of RT status (RT or no RT), initiation and continuation of ET may be associated with reduced risk of recurrence. Conclusion: Patients who opt for no adjuvant therapy, or who do not tolerate ET, are at increased risk of disease recurrence if they omit RT. Clinicians should consider the likelihood a patient will adhere to ET prior to recommending omission of RT. [ABSTRACT FROM AUTHOR]

Supercooling of micro- and nanoencapsulated phase change material is widely observed as their diameters depress to a limitation upon cooling. The aim of this study is to suppress the supercooling of nanoencapsulated n-octadecane (NanoC18) using a novel copolymer consisting of long n-alkyl side chains as shell. Nanoencapsulations of n-octadecane with various compositions of poly(methyl methacrylate- co-octadecyl methacrylate) copolymer as shells were carried out by means of miniemulsion polymerization. Fabrication, morphology, diameter distributions, phase change behaviours, and thermal stabilities of nanocapsules were investigated using Fourier transformed infrared spectroscopy, a field-emission scanning electron microscope, a transmission electron microscope, particle size distribution analysis, differential scanning calorimetry, and thermogravimetric analysis. The results indicate that a series of nanocapsules with core/shell structure and spherical shapes are fabricated with average diameters ranging from 373 to 398 nm. The average thickness of the shells is about 60 nm. All the NanoC18 crystallize into a stable triclinic phase via a metastable rotator phase (R) from the liquid phase. The crystallization temperature of n-octadecane within poly(methyl methacrylate) nanocapsules is considerably lower than that in bulk phase. Supercooling is effectively suppressed using the comb-like copolymer with crystallizable n-octadecyl side chains as shell. Octadecyl methacrylate is not only employed as a reactive costabilizer to suppress the influence of Ostwald ripening during the formation of nanocapsules but also as a functional monomer in the composition of the copolymer shell in order to suppress the supercooling of NanoC18. [ABSTRACT FROM AUTHOR]

In this paper, three robust zero-watermark algorithms named Direct Current coefficient RElationship (DC-RE), CUmulant combined Singular Value Decomposition (CU-SVD), and CUmulant combined Singular Value Decomposition RElationship (CU-SVD-RE) are proposed. The algorithm DC-RE gets the feature vector from the relationship of DC coefficients between adjacent blocks, CU-SVD gets the feature vector from the singular value of third-order cumulants, while CU-SVD-RE combines the essence of the first two algorithms. Specially, CU-SVD-RE gets the feature vector from the relationship between singular values of third-order cumulants. Being a cross-over studying field of watermarking and cryptography, the zero-watermark algorithms are robust without modifying the carrier. Numerical simulation obviously shows that, under geometric attacks, the performance of CU-SVD-RE and DC-RE algorithm are better and all three proposed algorithms are robust to various attacks, such as median filter, salt and pepper noise, and Gaussian low-pass filter attacks. [ABSTRACT FROM AUTHOR]

The wall loosening of guard cells differs from other types of plant cells. However, the regulation of wall loosening during stomatal movement is poorly understood. VfEXPA1 is an α-expansin gene cloned from Vicia faba epidermal strips. Expression of VfEXPA1 is regulated by darkness and submergence, and is not affected by light and abscisic acid (ABA). In situ hybridization showed that VfEXPA1 is expressed primarily in the guard cells. Overexpression of VfEXPA1 in transgenic tobacco accelerated light-induced stomatal opening, and increased both transpiration and photosynthetic rates under favorable growth conditions. Our results indicate the guard cell-expressed expansin VfEXPA1 plays an important role in regulation of stomatal opening. [ABSTRACT FROM AUTHOR]

Pharmacological, laser scanning confocal microscopic (LSCM), real-time PCR and spectrophotographic approaches are used to study the roles of hydrogen sulfide (HS) and nitric oxide (NO) in signaling transduction of stomatal movement response to ethylene in Arabidopsis thaliana. In the present study, inhibitors of HS synthesis were found to block ethylene-induced stomatal closure of Arabidopsis. Treatment with ethylene induced HS generation and increased L-/ D-cysteine desulfhydrase (pyridoxalphosphate-dependent enzyme) activity in leaves. Quantitative PCR analysis showed AtL-CDes and AtD-CDes transcripts were induced by ethylene. It is suggested that ethylene-induced HS levels and L-/ D-cysteine desulfhydrase activity decreased when NO was compromised. The data clearly show that ethylene was able to induce HS generation and stomatal closure in Atnoa1 plants, but failed in the Atnia1,nia2 mutant. Inhibitors of HS synthesis had no effect on ethylene-induced NO accumulation and nitrate reductase (NR) activity in guard cells or leaves of Arabidopsis, whereas ethylene was able to induce NO synthesis. Therefore, we conclude that HS and NO are involved in the signal transduction pathway of ethylene-induced stomatal closure. In Arabidopsis, HS may represent a novel downstream indicator of NO during ethylene-induced stomatal movement. [ABSTRACT FROM AUTHOR]

Aquaporins are implicated in a wide variety of plant physiological processes, although the mechanisms involved in their regulation are not fully understood. To gain further insight into the regulatory factors involved in this process, we used a yeast two-hybrid system to screen for potential binding partners to the Arabidopsis tonoplast intrinsic protein (TIP) AtTIP1;1. This was the first protein identified to be associated with high water permeability in vacuolar membranes from Arabidopsis thaliana. Using AtTIP1;1 as bait, a novel binding protein was identified in both yeast and plant cells. This prey protein, named AtSM34, was a 309 aa polypeptide with a predicted molecular mass of 34 kD and contained a single MYB/SANT-like domain. AtSM34 promoter:: GUS histochemical staining analysis detected AtSM34 expression in flowers, stems and leaves, particularly in the vascular tissues, in response to osmotic stress. AtSM34 expression was localized in the endoplasmic reticulum membrane, and sequence deletion analysis revealed that the N-terminal coding region (amino acids 1-83) was critical for this localization. Overexpression of AtSM34 resulted in hypersensitivity to exogenous mannitol, sorbitol and abscisic acid, and caused a significant delay in germination. AtSM34 interacted with AtTIP1;2 and AtTIP2;1, which are essential proteins for modulation of tonoplast permeability and highly expressed in germinating seedlings. These data indicate AtSM34 is a novel TIPs binding protein involved in the osmotic stress response of seedlings at an early stage of development. [ABSTRACT FROM AUTHOR]

Microcapsules containing n-Octadecane using styrene (St)-divinybenzene (DVB) co-polymer shells were synthesized by suspension-like polymerization. The effects of stirring rates and monomers/ n-Octadecane mass ratios on the average diameter and phase change properties of microencapsulated n-Octadecane (MicroC18) were investigated. The surface morphology, diameters, phase change properties and thermal decomposition temperature of MicroC18 were investigated by using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electronic Microscope (SEM), Differential Scanning Calorimeter (DSC), and Thermogravimetric Analysis (TGA). The average diameters of MicroC18 decreased with an increase of stirring rate. When the monomers/ n-Octadecane mass ratio of 1:1 is used, the enthalpy of MicroC18 reaches the highest-126 J/g. Surfaces of majority of MicroC18 show large concaves because of the production of reserved expansion space in the process of micro-encapsulation. The thermal decomposition temperature of MicroC18 is about 230 °C which is higher than that of MicroC18 using melamine-formaldehyde shell. [ABSTRACT FROM AUTHOR]

The plant-specific NAC (NAM, ATAF1/2, and CUC2) transcription factors have a regulatory function in developmental processes and stress responses. Notably a group of NAC members named NTLs (NTM1-Like) are membrane-tethered, ensuring plants rapidly respond to developmental changes and environmental stimuli. Our results indicated that ANAC089 was a membrane-tethered transcription factor and its truncated form was responsible for the physiological function in flowering time control. [ABSTRACT FROM AUTHOR]

Senescence is a complex and highly regulated process. Leaf senescence is influenced by endogenous developmental and external environmental signals. In this work, we found that expression of an Ap2/DREB-type transcription factor gene, Arabidopsis Rap2.4f ( At4g28140), was upregulated by salt, mannitol, and dark treatments. Constitutively overexpressing Rap2.4f under the control of the CaMV 35S promoter led to an increased chlorophyll degradation rate and upregulation of many senescence-associated genes in the transgenic Arabidopsis lines. Our results show that Rap2.4f is a positive regulator of senescence, promoting both developmental and dark-induced leaf senescence. [ABSTRACT FROM AUTHOR]

RecQ helicases play a central role in maintaining genome stability and may interact with some important cancer-related proteins such as BRCA1. Mutations of the human RecQ helicase genes WRN and BLM lead to rare autosomal recessive disorders, Werner and Bloom syndromes, which are associated with premature aging and cancer predisposition, including breast cancer. In this case–control study of 1,004 breast cancer cases and 1,008 controls, we tested the hypothesis that non-conservative amino acid exchanges in WRN (leu1074Phe), BLM (Met298Thr) and BRCA1 (Pro871Leu) are independently or jointly associated with the risk of breast cancer in Chinese women. We found that the variant genotype of WRN Leu1074Phe was associated with a 1.36-fold significantly increased risk of breast cancer (OR = 1.36, 95% CI = 1.06–1.74). Moreover, a significant gene–environment interaction was evident between WRN leu1074Phe and age at menarche ( Pint = 0.02). Subjects carrying Phe/Phe genotype and with earlier age at menarche had 3.58-fold increased risk of breast cancer (OR = 3.58, 95% CI = 2.54–5.05). However, we did not find the significant main effect of polymorphisms in BLM and BRCA1 and also no locus–locus interactions were identified between WRN, BLM and BRCA1. These findings indicate that WRN leu1074Phe variant may contribute to the susceptibility of breast cancer in Chinese women. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) foam containing phase change materials is a kind of new heat-insulating material which can store and release heat energy. The microencapsulated n-octadecane (MicroPCMs) with a styrene (St)–divinybenzene (DVB) co-polymer shell was synthesized by means of suspension-like polymerization. The surface morphology, diameter, enthalpy, and thermal stability were investigated by using scanning electronic microscope (SEM), differential scanning calorimeter (DSC), and TGA. The average diameter of the microcapsules is about 80 μm. The enthalpy of the microcapsule is about 126 J/g. PU foams containing MicroPCMs were fabricated by adding the MicroPCMs in reactants. MicroPCMs are evenly inserted inside the foam and the enthalpy of the foam rises with the increase of the content of microcapsules. The enthalpy is about 24 J/g for the foam containing 26.8 wt% MicroPCMs. [ABSTRACT FROM AUTHOR]

In this study, we cloned the OsHAL3 gene from rice Oryza sativa. Alignment analysis revealed that OsHAL3 has a high sequence identity to Dfp protein in Escherichia coli and AtHAL3a protein in Arabidopsis thaliana, which have 4′-phosphopantothenoylcysteine decarboxylase (PPC-DC) activity. OsHAL3 can complement mutation in the E. coli dfp gene encoding PPC-DC, so that the mutant strains with OsHAL3 can grow on rich media at 42°C and on VB minimal media at 30°C. Complementation tests with point mutations of OsHAL3 suggested that the conserved Cys176 residue of OsHAL3 is a key active-site residue. The mutant OsHAL3 G180A has a partly reduced activity. Related mRNA-level analysis showed that the OsHAL3 gene is induced by calcium pantothenate in rice. [ABSTRACT FROM AUTHOR]

The expression of the gene OsITL1 coding for the inositol 1,3,4-trisphosphate 5/6-kinase protein was induced by 200 mM NaCl or dehydration. The expression of OsITL1 in response to NaCl and dehydration suggests the possible functions of OsITL1 in osmotic stress responses; however, physiological tests indicate that the expression of OsITL1 in tobacco decreases tolerance to NaCl during germination and seedling development. This result was consistent with that obtained on treatment of mature tobacco seedlings with NaCl (200 mM), suggesting that OsITL1 inversely regulates plant responses to osmotic stress. [ABSTRACT FROM AUTHOR]

NO (nitric oxide), known as a key signal molecule in plant, plays important roles in regulation of stomatal movement. In this study, microtubule dynamics and its possible mechanism in the NO signal pathway were investigated. The results were as follows: (i) In vivo stomatal aperture assays revealed that both vinblastine (microtubule-disrupting drug) and SNP (exogenous NO donor) prevented stomatal opening in the light, and vinblastine even could enhance the inhibitory effect of SNP, whereas taxol (a microtubule-stabilizing agent) was able to reduce this effect; (ii) microtubules in the opening Arabidopsis guard cells expressing GFP:α-tubulin-6 (AtGFP:α-tubulin-6) were organized in parallel, straight and dense bundles, radiating from the ventral side to the dorsal side, and most of them were localized perpendicularly to the ventral wall; (iii) under the same environmental conditions, treated with SNP for 30 mm, the radial arrays of microtubules in guard cells began to break down, twisted partially and became oblique or exhibited a random pattern; (iv) furthermore, the involvement of cytosolic Ca2+ in this event was tested. Stomatal aperture assays revealed that BAPTA-AM (a chelator of Ca2+) greatly suppressed the effect of NO on stomatal closure; however, it did not show the same function on stomatal closure induced by vinbiastine. When BAPTA-AM was added to the SNP-pretreated solution, the SNP-induced disordered microtubulue cytoskeleton in guard cells underwent rearrangement in a time-dependent manner. After 30 mm of treatment with BAPTA-AM, the cortical microtubules resumed the original radial distribution, almost the same as the control. All this indicates that NO may promote rearrangement of microtubule cytoskeleton via elevation of [Ca2+]cyt (free Ca2+ concentration in the cytoplasm), finally leading to stomatal closure. [ABSTRACT FROM AUTHOR]

In rice, the characterization of OsEBP-89 is inducible by various stress-or hormone-stimuli, including ethylene, abscisic acid (ABA), jasmonate acid (JA), drought and cold. Here, we report the investigation of essential DNA region within OsEBP-89 promoter for methyl jasmonic acid (MeJA) induction. PLACE analysis indicates that this promoter sequence contains multiple potential elements in response to various stimuli. First, we fused this promoter with GUS gene and analyzed its expression under MeJA treatment through Agrobacterium infiltration mediating transient expression in tobacco leaves. Our results revealed that this chimeric gene could be inducible by MeJA in tobacco leaves. To further determine the crucial sequences responsible for MeJA induction, we generated a series of deletion promoters which were fused with GUS reporter gene respectively. The results of transient expression of GUS gene driven by these mutant promoters show that the essential region for MeJA induction is positioned in the region between −1200 and −800 in OsEBP-89 promoter containing a G-box (−1127), which is distinct from the essential region containing ERE (−562) for ACC induction. In all, our finding is helpful in understanding the molecular mechanism of OsEBP-89 expression under different stimuli. OsEBP-89, essential DNA region, methyl jasmonic acid, transient assay, promoter, tobacco leaves [ABSTRACT FROM AUTHOR]

There is increasing evidence for considerable interlinking between the responses to heat stress and oxidative stress, and recent researches suggest heat shock transcription factors (Hsfs) play an important role in linking heat shock with oxidative stress signals. In this paper, we present evidence that AtHsfA2 modulated expression of stress responsive genes and enhanced tolerance to heat and oxidative stress in Arabidopsis. Using Northern blot and quantitative RT-PCR analysis, we demonstrated that the expression of AtHsfA2 was induced by not only HS but also oxidative stress. By functional analysis of AtHsfA2 knockout mutants and AtHsfA2 overexpressing transgenic plants, we also demonstrated that the mutants displayed reduced the basal and acquired thermotolerance as well as oxidative stress tolerance but the overexpression lines displayed increased tolerance to these stress. The phenotypes correlated with the expression of some Hsps and APX1, ion leakage, H2O2 level and degree of oxidative injuries. These results showed that, by modulated expression of stress responsive genes, AtHsfA2 enhanced tolerance to heat and oxidative stress in Arabidopsis. So we suggest that AtHsfA2 plays an important role in linking heat shock with oxidative stress signals. [ABSTRACT FROM AUTHOR]

The genetic regulation of stomatal movement mainly depends on an efficient control system of gene expression, and guard cell-specific promoter is becoming the best choice. Here we combined the dehydration responsive element (DRE) with guard cell specific element (GCSE) to construct a novel promoter, DGP1. Histochemical assays in transgenic tobacco carrying β-glucuronidase (gus) gene fused to DGP1 demonstrated that GUS activity was found to be highly inducible by drought treatment and specifically restricted to guard cells. No GUS activity was detected in roots, stems or flowers after treatment. Further quantitative analysis showed that GUS activity in the epidermal strips was apparently induced by dehydration and dramatically increased with the elongation of treatment. The GUS activity after 8 h treatment was 179 times that of those without treatment. Although GUS activity in roots, stems or mesophyll increased after treatment, no great changes were observed. These results suggested that DGP1 could drive target gene expressed in guard cells when plant is subjected to drought stress. And this gets us prepared to control opening and closing of stomata through plant gene engineering. [ABSTRACT FROM AUTHOR]

OsNHX1 gene (Na+/H+ antiporter gene ofOryza sativa L.) was introduced into Poplar 84K withAgrobacterium tumefaciens- mediated transformation. PCR, Southern and Northern blot analysis showed thatOsNHX1 gene was incorporated successfully into the genome of Poplar 84K and expressed in these transgenic plants. Salt tolerance test showed that three lines of transgenic plants grew normally in the presence of 200 mmol/L NaCl, while the Na+ content in the leaves of the transgenic plants grown at 200 mmol/L NaCl was significantly higher than that in plants grown at 0 mmol/L NaCl. The osmotic potential in the transgenic plants with high salinity treatment was lower than that of control plants. Our results demonstrate the potential use of these transgenic plants for agricultural use in saline soils. [ABSTRACT FROM AUTHOR]

OsNHX1 gene (Na+/H+ antiporter gene of Oryza saliva L.) was introduced into Poplar 84K with Agrobacterium tumefaciens-mediated transformation. PCR, Southern and Northern blot analysis showed that OsNHX1 gene was incorporated successfully into the genome of Poplar 84K and expressed in these transgenic plants. Salt tolerance test showed that three lines of transgenic plants grew normally in the presence of 200 mmol/L NaCl, while the Na+ content in the leaves of the transgenic plants grown at 200 mmol/L NaCl was significantly higher than that in plants grown at 0 mmol/L NaCl. The osmotic potential in the transgenic plants with high salinity treatment was lower than that of control plants. Our results demonstrate the potential use of these transgenic plants for agricultural use in saline soils. [ABSTRACT FROM AUTHOR]

The elongation of pollen tube is an important process of sexual reproduction in higher plant. Cytoskeleton plays a major regulatory role in the elongation of pollen tubes. But whether membrane skeleton is involved in the pollen tube elongation is not clear. In this study, immunochemical detection of spectrin-like protein has been carried out in pollen tubes. By use of 2-dimensional electrophoresis(2DE) and western blotting, two spectrin-like proteins are found, one is 150 kD, and the other is 105 kD, with pl being 4.54 and 4.39, respectively. 150 kD spectrin-like protein is located in plasma membrane of pollen tube and 105 kD spectrin-like protein is located in cytoplasm, probably functioning as a subunit to form a dimmer (210 kD) in vivo. The elongation of pollen tubes is inhibited after spectrin antibody was injected into a growing pollen tube. These results suggest that spectrin-like proteins exist in pollen tube and play an important regulating role in the elongation process of pollen tubes from lily. [ABSTRACT FROM AUTHOR]

Investigates the role of acetylcholine (Ach) on plant root-shoot communication using the root-split system of Vicia faba L. Decrease of Ach content in root tips and increase in the xylem sap transported per time unit, due to a slight osmotic stress; Probable function of Ach content decrease to regulate stomatal behavior.

Discusses the involvement of Ca2+/CaM in the signal transduction of acetylcholine regulating stomatal movement. How the neutrotransmitter acetylcholine (ACh) is able to regulate the movement of stomata in plants; Demonstration that Ca2+/CaM are also involved in the ACh regulated stomatal movement.

Focuses on a study which addressed the existence and localization of integrin-like guard cells of Vicia faba. Materials and methods; Results and discussion.

Deals with a study which examined the distribution of aquaporin in the plasma membrane of maize root protoplasts. Function of aquaporins; Materials and methods; Presentation of results; Conclusion.

In animal cells, actions of acetylcholine depend on its binding to specific receptors. Activation of nicotinic acetylcholine receptor can affect the membrane permeability to ions directly. As concerned about acetylcholine regulating stomatal movement, nicotinic acetylcholine receptor may also be involved. Experiments with nicotinic acetylcholine receptor antagonist (D-tubocurarine) and agonist (nicotine) showed that nicotinic acetylcholine receptor was involved in acetylcholine inducing stomata1 opening. In addition, these effects of D-tubocurarine and nicotine on stomatal movement can only be found in medium containing K+ while no effects can be found in medium containing Ca2+, The result by Western blotting showed that at least α-and β-subunits of nicotinic receptor existed in microsomes of guard cell protoplasts. It was found that the distribution of nicotinic acetylcholine receptor was mainly on the surface of protoplasts as shown by FITC labelled α-bungarotoxin. The results above show that nicotinic acetylcholine receptor exists in guard cells and mediates acetylchlone to induce stomatal opening. [ABSTRACT FROM AUTHOR]

A novel colorimetric immunoassay for the detection of Staphylococcus aureus (S. aureus) based on a combination of immunomagnetic separation and signal amplification via etching-enhanced peroxidase-like catalytic activity of gold nanoparticles (AuNPs) was developed. Nanoconjugates composed of gold and iron oxide nanoparticles were synthesized and further modified with antiS. aureus immunoglobulin Y (IgY), which was used for the selective enrichment and rapid separation of target bacteria in complex matrices. AuNPs functionalized with antiS. aureus aptamer were used as an artificial enzyme which has peroxidase-like catalysis activity. Catalytic activity of AuNPs is inhibited by modifying aptamer. However, catalysis of modified AuNPs remarkably enhanced by hydrogen peroxide etching. Based on collecting unbound modified AuNPs in the supernatant and 3,3′,5,5′-tetramethylbenzidine-hydrogen peroxide reporting system, the yellow color of solution decreases linearly with increasing the concentration of S. aureus ranging from 10 to 106 cfu/mL. The limit of detection is 10 cfu/mL, and total detection time is 65 min. The recoveries of the S. aureus spiked in food samples are 88.2–119.8%. [ABSTRACT FROM AUTHOR]

Provides information on a study which showed that agonists of muscarinic receptor could induce stomatal opening, while the antagonists could block stomatal opening induced by acetylcholine. Materials and methods; Results and discussion.