Cl Uptake Research Articles

Factors influencing contact lenses uptake among school-going children and teenagers with myopia attending selected eye clinics in Kenya

ObjectiveContact lens (CL) use for myopia correction among children and teenagers has become a focal point of global interest. Yet, spectacles remain dominant for vision correction in this age group. This study investigated the factors affecting CL uptake among myopic school-going children and teenagers attending Kenyan eye clinics. Study DesignCross-sectional study. MethodsA survey conducted across 13 Kenyan eye clinics, involving myopic participants aged 8–19 years. Data collection employed a mixed-method using validated semi-structured questionnaires that also included a 3-level Likert scale to elicit responses regarding factors that influenced the uptake of CLs. Analysis techniques included descriptive statistics, chi-square, and Cramer's V. Results85 participants, with a mean age of 13.4 ± 2.1 years, who were more of females (54.1%) were included in the study. While CL uptake was low (17.6%), spectacles remained the preferred myopia correction method among the participants. Factors favoring CL preference were appropriate visual clarity with CL (59%), enhanced self-esteem and social acceptance (64%). Major barriers to CL uptake were fear of eye injuries (60%), limited CL knowledge (55%), and fewer CL professionals (48%). Eye care professionals were the primary CL information source. A weak association was observed between spectacles’ perceived bulkiness and CL uptake (Cramer's V: 0.223, p = 0.121). However, vision clarity (Cramer's V: 0.387, p = 0.002) and social acceptance (Cramer's V: 0.351, p = 0.005) showed stronger associations with CL uptake in children and teenagers in the study. ConclusionWhile information gaps and limited professional availability hinder CL uptake among Kenyan students, benefits like better vision clarity and improved social acceptance promote their use. Efforts to address information gaps and highlight CL advantages are recommended to foster broader acceptance.

Traits contributing to salinity tolerance in rice genotypes from the Mekong Delta

AbstractIncreasing sea level rise and subsequent salinization in mega deltas, such as the Vietnamese Mekong Delta (VMD), pose a risk to rice (Oryza sativa L.) production during the dry season. This study investigated the salinity resistance of a selection of common rice genotypes from the VMD along with an international check, IR64. The 20 rice varieties were grown hydroponically for 5 weeks in a greenhouse and then exposed to three levels of NaCl concentration (0 mM, 50 mM and 100 mM) over a period of 2 weeks to determine their susceptibility to salinity. Rice plants were scored and SPAD (leaf greenness) and PRI (photochemical reflectance index) were measured on the youngest fully developed leaf on the main tiller. After harvesting the 7‐week‐old plants, biomass and ion (K+, Cl−, Na+) content were determined by organ across all tillers. Averaged over all varieties, both at 50 mM and 100 mM NaCl, there was a significant reduction in plant biomass, 39% and 52% respectively. However, the effect of the NaCl treatments and the uptake of Cl− and Na+ were significantly different between varieties (p < .0001). Using biomass and ion content as part of a multivariate analysis, varieties were classified according to their susceptibility to salinity and their predominant strategy towards managing ion accumulation. The grouped varieties were further characterized by patterns in Cl− and Na+ partitioning and nondestructive parameters such as SPAD and PRI.

Ion uptake and distribution in sweet potato genotypes subjected to salt stress is not driven by transpiration

AbstractPotassium is taken up actively by the plant, whereas sodium is often either competing for the same uptake mechanisms or uptake and distribution are driven by the transpirational volume flow in the shoots of plants grown under salinity. Reducing transpiration rate is regarded as an adaptation mechanism to reduce leaf tissue salt load. In combination with a high K uptake, plants may be able to maintain growth and are, thus, seen as salt‐tolerant. Little is known about these mechanisms in sweet potato (Ipomoea batatas L.). Therefore, cuttings of two sweet potato genotypes contrasting in salinity tolerance (CIP 188002.1, tolerant; CIP 189151.8, sensitive) were subjected to 0 and 50 mM NaCl root zone salinity in a hydroponic system and grown under low (0.76 kPa) and high (2.27 kPa) vapour pressure deficit (VPD) to create differences in transpiration. After 18 days of initial hydroponic growth, NaCl was added for another 33 days. Cumulative plant water loss and total uptake of Na, K and Cl were determined for all plants and treatments. Transpirational water loss was twice as high under high VPD as compared to low VPD conditions, but genotypic Na and Cl accumulation remained almost the same. In contrast to plants subjected to salt stress under low VPD conditions, genotypes under high VPD conditions differed significantly in transpiration. However, in both genotypes transpirational water loss from individual leaves and Na or Cl accumulation were not correlated, under high VPD younger leaves of CIP 188002.1 (tolerant) accumulated more than twice as much potassium than in CIP 189151.8 (sensitive). The distribution of the three ions across leaf positions and within one leaf position between petiole and leaf blade differed strongly between the two genotypes. Tolerant CIP 188002.1 accumulated up to five times more sodium and potassium in the leaf petioles in the middle‐aged and young leaf positions than in the leaf blade, whereas in sensitive CIP 189151.8 neither ion was preferentially accumulated in the petioles. This was independent of salinity treatment and VPD conditions. In contrast, hyperaccumulation of Cl in petioles only occurred under high VPD conditions in the petioles of the tolerant genotype, but not under low VPD conditions, indicating a VPD sensitivity for Cl distribution in sweet potato. While we conclude that transpirational volume flow is not a main driving force for Na and Cl uptake and distribution within the plant, we discuss potential pathways leading to the hyperaccumulation of sodium and potassium in the leaf petioles of the tolerant genotype. We suggest studies on HKT transporter activities in the petioles as an object of further studies in sweet potato.

Propagation Methods and Mulching Modulate the Quantum Yield, Ionic Relations, and Production Components of Sour Passion Fruit under Salt Stress

In semiarid regions of Brazil, water and/or soil salinity is one of the limiting factors for sour passion fruit production. Low rainfall rates combined with edaphic conditions (high concentrations of soluble salts) intensify deleterious effects on plants. Thus, strategies that minimize the effects of salt stress, e.g., grafting with tolerant species and soil mulching, are extremely important to ensure the expansion of irrigated fruit farming in this region. From this perspective, this study aimed to evaluate the effect of grafting and mulching on the quantum yield, ionic relations, and fruit production of sour passion fruit irrigated with moderately saline water. The experiment was conducted under field conditions in split plots, in a 2 × (2 × 2) factorial arrangement to evaluate the combination of low and moderate salinity water (main plot) with the propagation method (seeds and grafting on P. cincinnata) and without and with plastic mulching (subplots), with four replications and three plants per plot. The ionic relations in passion fruit leaves were increased with the use of rootstocks and plastic mulching under irrigation with moderately saline water. The use of mulching increased the yield of photosystem II in sour passion fruit. The passion fruit plants propagated by seeds had 187.52% more fruits than those grafted onto P. cincinnata. The use of rootstocks with P. cincinnata in sour passion fruit restricted the uptake of Na and Cl but reduced fruit production.

Diurnal changes in apoplast bypass flow of water and ions in salt-stressed wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.).

The aim of the present study was to quantify the contribution of apoplastic bypass flow to the uptake of water and salt across the root cylinder of wheat and barley during day and night. Plants were grown on hydroponics until they were 14-17d old and then analysed over a single day (16h) or night (8h) period while being exposed to different concentrations of NaCl (50, 100, 150 and 200 mM NaCl). Exposure to salt started just before the experiment (short-term stress) or had started 6d before (longer-term stress). Bypass flow was quantified using the apoplastic tracer dye 8-hydroxy-1,3,6-pyrenesulphonic acid (PTS). The percent contribution of bypass flow to root water uptake increased in response to salt stress and during the night and amounted to up to 4.4%. Bypass flow across the root cylinder of Na+ and Cl- made up 2-12% of the net delivery of these ions to the shoot; this percentage changed little (wheat) or decreased (barley) during the night. Changes in the contribution of bypass flow to the net uptake of water, Na+ and Cl- in response to salt stress and day/night are the combined result of changes in xylem tension, the contribution of alternative cell-to-cell flow path and the requirement to generate xylem osmotic pressure. This article is protected by copyright. All rights reserved.

Assessment of the absorption ability of nitrate and lead by japanese raisin under salt stress conditions

Heavy metals pollution is an important challenge that was cussed by human activity, this stress decreases under salinity. The aim of this study was to investigate the ability of Japanese raisin in the absorption of nitrate (0, 30, and 60 mgL-1) and lead (0, 300, and 600 mgL-1) under salinity stress (0 as control and 3 and 6 dSm-1). Results showed that the studied plant continued to uptake nitrate and potassium under stress conditions of Pb and salinity. Although Na and Cl uptake were observed as a defense mechanism in the plant, the K/Na ratio, and K content increased from 1 to 6 and from 1.8 to 5%, respectively. Also, the most appropriate physiological responses were observed at treatments under contamination level of 300 mg Pb and salinity level of 3 dSm-1, so that the synthesis of malondialdehyde (MDA) and enzymatic activity increased at these levels of HMs and salinity. Based on the results, the studied species were able to uptake moderate concentrations of Pb (34.1-71mg kg-1) under experimental conditions. Hence, its potential for the clean-up of some contaminants in the environment can be considered by researchers for further research.

Efektivitas Aplikasi Amonium Klorida dan Sumber Kalium Berbeda pada Pertumbuhan dan Produksi Jagung Manis (Zea mays saccharata Sturt)

Nitrogen (N) fertilizer of the urea type is very commonly used in Indonesia. The demand for this fertilizer is expected to increase, so an alternative is needed as a complement. Ammonium chloride (NH4Cl) is a by-product produced in the soda ash industry. This compound contains 26% N, which can be an alternative source of N nutrients for plants. The level of the following element, namely chlorine (Cl), is relatively high, so it is a concern that might affect the plant growth. This field experiment aimed to evaluate the effect of the application of ammonium chloride combined with potash fertilizers on the growth, production, and uptake of N and Cl nutrients in sweet corn plants. The trial was designed in a randomized group with nine treatments of 0%, 100%, 150%, and 200% N, combined with potassium sources from KCl and K2SO4. As a comparison, the source of N is urea at a dose of 100% N is referred to as the standard N treatment. Parameters observed included plant height, the weight of corn cobs and corn stover, N and Cl nutrient uptakes in seeds, leaves, and stems. The results showed that the application of ammonium chloride combined with different K sources markedly affected plant height, cob and plant stover weight, and N and Cl uptakes of sweet corn compared to controls. Applying N-ammonium chloride with KCl and K2SO4 showed no significant effect in growth and yield compared to standard N. The N dose showed no significant effect on plant growth and yield compared to the standard N dose.
 
 Keywords: by-product, nitrogen fertilizer, soda ash

Corrigendum for ‘Is inquiry learning unjust? Cognitive load theory and the democratic ends of education’ by Tanchuk (2020)

Journal of Philosophy of EducationEarly View CORRIGENDUMFree Access Corrigendum for ‘Is inquiry learning unjust? Cognitive load theory and the democratic ends of education’ by Tanchuk (2020) This article corrects the following: Is Inquiry Learning Unjust? Cognitive Load Theory and the Democratic Ends of Education NICOLAS TANCHUK, Volume 54Issue 5Journal of Philosophy of Education pages: 1167-1185 First Published online: May 30, 2020 First published: 17 June 2022 https://doi.org/10.1111/1467-9752.12664AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat In Tanchuk (2020), there was an error in the following sentence https://doi.org/10.1111/1467-9752.12435: The activist work by educators and cognitive scientists in the ResearchEd community, alongside Bennett's acquiring a leadership position in Ofsted, has coincided with an increased uptake of CL theorists’ findings in policy and a critical re-appraisal of inquiry-based teaching methods, particularly in conservative circles. It should be: The activist work by educators and cognitive scientists in the ResearchEd community, alongside Bennett's acquiring a role as a behaviour consultant with the Department for Education (Lightfoot, 2020), has coincided with an increased uptake of CL theorists’ findings in policy and a critical re-appraisal of inquiry-based teaching methods, particularly in conservative circles. REFERENCES Lightfoot, L. (2020) England's school behaviour tsar: ‘Letting children off again and again is like a snooze alarm.’ The Guardian, 8 August, https://www.theguardian.com/education/2020/aug/08/englands-school-behaviour-tsar-letting-children-off-again-and-again-is-like-a-snooze-alarm. Google Scholar Tanchuk, N. (2020) Is inquiry learning unjust? Cognitive load theory and the democratic ends of education. Journal of Philosophy of Education, 54, 1167– 1185. https://doi.org/10.1111/1467-9752.12435CrossrefWeb of Science®Google Scholar Early ViewOnline Version of Record before inclusion in an issue ReferencesRelatedInformation

Uptake of chloride and iso-saccharinic acid by cement: Sorption and molecular dynamics studies on HCP (CEM I) and C-S-H phases

The uptake of chloride and ISA by cement in the degradation stage I was investigated with a combination of sorption experiments and MD simulations. The retention of 36Cl decreases with increasing [Cl−]tot in cement pore water. The uptake of 36Cl is dominated by sorption phenomena and the formation of the Friedel's salt at low and high [Cl−]tot, respectively. ISA sorbs moderately on HCP, and a one-site Langmuir isotherm was used to satisfactorily model the sorption data. MD simulations highlight the key role of Ca in the binding of ISA to C-S-H. This work provides a sound basis for predicting the uptake of chloride and ISA by HCP in the context of L/ILW repositories, together with new insights for the mechanistic understanding of ISA uptake.

Evaluation of integrated ultrasound and CaCl2 in hydrocooling water on the quality of ‘Bing’, ‘Lapins’, and ‘Sweetheart’ cherries stored in modified atmosphere packaging

Sweet cherry is a highly perishable fruit with a short storage life. Although CaCl2 dips positively affect the quality of sweet cherries, traditional sanitizer (i.e. NaClO) in the cleaning step contributes to fruit oxidation. The primary purpose of this study was to evaluate whether integrated applications of a chemical-free sanitizing technology (ultrasound) and CaCl2 in hydrocooling water (0 °C) had the potential in improving the quality of ‘Bing’, ‘Lapins’, and ‘Sweetheart’ cherries either packing in polyethylene (PE) or modified atmosphere packaging (MAP) bags. Regardless of cultivar and packaging type, ultrasound showed a similar effect as NaClO on quality attributes, decay, and antioxidant compounds (i.e. DPPH free radicals scavenging capacity, ferric reducing antioxidant power (FRAP), total phenolics (TP), and total flavonoids (TF)). However, NaClO induced high rates of stem browning (SB) and pitting in ‘Bing’ and ‘Lapins’ cherries packed with PE and MAP bags. Fortunately, Ultrasound + MAP provided a greater benefit in reducing SB in ‘Bing’ cherries. Adding 22.5–90 mM CaCl2 to hydrocooling water effectively enhanced calcium (Ca) and chloride (Cl) uptake in ‘Bing’ and ‘Lapins’, but not in ‘Sweetheart’. The cubic model showed high correlations between applied CaCl2 concentrations and postharvest disorders. Furthermore, CaCl2 concentration at 22.5–45 mM had stronger effects on reducing pitting and retaining TP in all three cultivars, irrespective of packaging type. However, increasing the application of CaCl2 concentration to 90 mM caused salt injury. Ultrasound did not provide an additional effect in increasing Ca and Cl uptake when it was combined with 22.5 mM CaCl2. However, this combination treatment retained high FF and SPF in all three cultivars packed with PE or MAP bags. Additionally, CaCl2 + ultrasound + MAP further reduced decay incidence in ‘Bing’ and ‘Lapins’ cherries and maintained high TP in ‘Lapins’ and ‘Sweetheart’ cherries, compared to the CaCl2 + ultrasound + PE treatment. Overall, the ultrasound with 22.5 mM CaCl2 in hydrocooling water slowed down quality deterioration, delayed disorders development, and improved antioxidant metabolism in MAP cherries.

Integrated application of plant growth promoting rhizobacteria and biochar improves salt tolerance in eggplant seedlings

A pot study was conducted to determine the effects of the combination of plant growth promoting rhizobacteria (PGPR) and biochar on the growth, physiological, and biochemical characteristics of eggplant seedlings under salinity stress. The greenhouse experiment included two salinity levels of NaCl [S0 (0 mM NaCl) and S1 (100 mM NaCl)], three biochar levels [B0 (non-biochar), B1 (5%) and B2 (10%)] and two PGPR [R0 (non-PGPR), R1 (combination of Bacillus megaterium TV-6D, Paenibacillus polymyxa KIN- 37, and Pantoea agglomerans RK92). Results showed that plant growth, relative leaf water content (LRWC), and chlorophyll content of eggplant seedlings decreased significantly, while malondialdehyde (MDA), hydrogen peroxide (H2O2), proline, sucrose and ABA content, and electrolyte leakage (EL) increased significantly with increase in salinity levels. Biochar and PGPR applications mitigated the negative influence of salinity stress on plant growth and physiological and biochemical characteristics of eggplant seedlings, enhancing chlorophyll content, plant nutrient element uptake, and antioxidant enzyme activity. The enhanced salinity tolerance due to biochar and PGPR applications could be associated with a significant reduction in Na and Cl uptake, MDA, H2O2 and EL and an increase in LRWC, chlorophyll content, antioxidant activity and plant nutrient element uptake. Therefore, it can be concluded that combining biochar and PGPR could be used to minimize the detrimental impacts of salinity stress conditions in eggplant seedlings.

Timing of potassium chloride application effect on soil and potato uptake of chloride

AbstractPotassium chloride (KCl) is often used to supply K for potato (Solanum tuberosum L.) production; it is the least costly K fertilizer. However, crop uptake of Cl can reduce diagnostic petiole NO3–N and reduce tuber specific gravity. This trial evaluated the effect of K fertilizer source (KCl vs. sulfate of potash [SOP] and sulfate of potash magnesia [KMag]) and fertilizer application timing on Cl, S, N, and K in soil, petioles, and whole plant biomass. Fertilizers were applied at 224 kg K2O ha–1 at three application timings: 210 d before planting (fall preplant), 14 d before planting (spring preplant), or 35 d after planting (Layby) to a sandy loam soil in Hermiston, OR. Nitrogen fertilizer was applied by overhead sprinklers during the growing season. Potassium source and timing had minimal effect on crop S, N, and K uptake. Crop Cl response reflected a fertilizer source × timing interaction. Fall‐applied KCl did not increase plant Cl above that observed for KMag and SOP treatments. Spring or summer‐applied KCl increased plant Cl concentrations. The most likely explanation for this response pattern was leaching of Cl below rooting depth with fall fertilizer application. Findings of importance for potato production practices in our region included: (a) fall‐applied Cl was not taken up by the crop, and so did not represent a risk to potato tuber quality; (b) elevated concentrations of petiole Cl from preplant or in‐season KCl application did not affect petiole NO3–N.

Water Intake and Ion Exchange in PEDOT:Tos Films upon Cyclic Voltammetry: Experimental and Molecular Dynamics Investigation

Conductive polymer PEDOT:Tos (3,4-ethylenedioxythiophene doped with molecular tosylate) gained considerable attention in various devices for bioelectronic applications, such as organic transistors and sensors. Many of these devices function upon oxidation/reduction processes in contact with aqueous electrolytes. So far, theoretical insight into morphological changes, ion injection, and water intake during these processes was rather limited. In the present work, we combined experiments and molecular dynamics simulations to study the water intake, swelling, and exchange of ions in the PEDOT:Tos film during cyclic voltammetry. We showed that the film underwent significant changes in morphology and mass during the redox processes. We observed both experimentally and in simulations that the film lost its mass during reduction, as tosylate and Na were expelled and gained mass during oxidation mainly due to the uptake of anions, i.e., tosylate and Cl. The results were in line with the UV–VIS–NIR absorption measurements and X-ray photoelectron spectroscopy (XPS) measurements, which revealed that during the redox process a portion of Tos was replaced by Cl– as the counterion for PEDOT. Also, the relative mass change between the most oxidized and reduced states was ∼10 to 14% according to both experiments and simulations. We detected an overall material loss of the film during voltammetry cycles indicating that a portion of the material leaving the film during reduction did not return to the film during the consecutive oxidation. Our combined experimental/simulation study unraveled the underlying molecular processes in the PEDOT:Tos film upon the redox process, providing the essential understanding needed to improve and assess the performance of bioelectronic devices.

Role of Grafting in Tolerance to Salt Stress in Melon (Cucumis melo L.) Plants: Ion regulation and antioxidant defense systems

Grafting in vegetables is a method that has been commonly used in recent years, not just for the treatment of soil borne diseases and pests, but also to facilitate higher abiotic stress tolerance under conditions such as salinity. Herein, it was aimed to determine if the salt tolerance of two salt-susceptible melon genotypes, SCP-1 and SCP-2, could be improved by grafting onto TLR-1 and TLR-2, which are salt-tolerant melon genotypes, and Albatros commercial melon rootstock. The grafted plants were grown in plastic pots containing a peat: perlite mixture and exposed to NaCl at doses of 0 and 200 mM under greenhouse conditions. The salt-tolerant rootstock significantly diminished the damaging effects caused by salt stress via a reduction in the uptake of Na and Cl, which enhanced Ca and K uptake and micronutrition. Stress- induced activities of catalase, superoxide dismutase, ascorbate peroxidase, and glutathione reductase were considerably higher in the grafted plants. The results showed that grafting salt susceptible plants onto the salt-tolerant rootstock improved the growth regulation. The salt tolerance of the grafted melon seedlings may have partially been the result of the decreased Na and Cl, and malondialdehyde contents and higher antioxidant enzyme activities.

19 DIET-INDUCED OBESITY UNIQUELY REGULATES GLUCOSE AND NACL ABSORPTION IN SPRAGUE DAWLEY RAT SMALL INTESTINAL EPITHELIAL CELLS

Background Traditional coupled NaCl absorption occurs via the dual operation of Na:H (NHE3) and Cl:HCO3 (DRA/PAT1) exchange in the brush border membrane of villus cells in the mammalian small intestine. In genetic models of obesity (Zucker rat and Tallyho mouse) and humans, coupled NaCl absorption was not affected. However, in these animal models, a novel coupling of Na-glucose co-transport (SGLT1) and Cl:HCO3 exchange was increased, potentially important in the pathogenesis of diabetes and hypertension associated with obesity. Human obesity is both genetic and environmental (e.g. diet mediated). But it is not known whether this novel coupled NaCl absorptive pathway is affected in diet-induced obesity (DIO). Hypothesis Novel coupled NaCl absorption mediated by SGLT1 and DRA/PAT1 is stimulated in DIO. Aim Determine the mechanisms of regulation of SGLT1 and DRA/PAT1 in DIO. Methods Sprague Dawley rats were fed with a high-fat diet (HFD; 60% fat calories) from 12-18 wks of age to induce obesity. Control rats were fed with standard chow. BBM vesicles (BBMV) were prepared from villus cells by Mg precipitation. Phlorizine sensitive, 3H-OMG uptake for SGLT1; amiloride-sensitive, 22Na uptake for NHE3 and DIDS sensitive 36Cl uptake for Cl:HCO3 exchange was performed in villus cell BBMV. Na/KATPase activity was determined as inorganic phosphate release. Western blot studies were performed using rat specific antibodies. Results In intact rat villus cells, SGLT1 uptake was significantly increased in HFD rats (2.4±0.2 nmol/mg protein×2 min in control and 6.4±0.6 in HFD; n=4, p Conclusions In DIO, BBM SGLT1 activity was stimulated in villus cells from HFD rats. This is not due to the altered Na extruding capacity of the cell. Cl:HCO3 exchange was also stimulated in DIO while NHE3 remained unaffected. These data indicate that in DIO, while the traditional coupled NaCl absorption is unaffected, a novel coupled NaCl absorptive pathway, via SGLT1 and DRA/PAT1 is stimulated resulting in enhanced glucose and NaCl absorption which is likely important in the pathophysiology of diabetes and hypertension of obesity.

Exogenous boron alleviates growth inhibition by NaCl stress by reducing Cl− uptake in sugar beet (Beta vulgaris)

This study aimed to better understanding the mechanism underlying the interaction between boron and NaCl and may provide methods to improve sugar beet production in saline soils. Sugar beet seedlings were treated with different concentrations of boron and NaCl. The flame photometer and ion chromatography were used to determine the ion content. And the uptake of Cl− by beet roots, was measured by non-invasive micro-test technology (NMT) and in vivo uptake system. The qPCR was used to measure the relative expression of the genes encoding ion transporters. In this study, we demonstrate that application of 750 µM boron markedly mitigated the growth inhibition of sugar beet seedlings caused by 300 mM NaCl, as reflected in dry and fresh weight, leaf area, chlorophyll content, and net photosynthetic rates. Both Na+ and K+ in the plants were not affected by treatment with boron. However, boron markedly reduced the Cl− content of sugar beet seedlings. Boron profoundly upregulated the expression of CLC-b, CLC-c, CLC-f and downregulated the expression of NIP5, NIP6 and AKT1 under NaCl stress. Our results indicate that exogenous boron reduced Cl− content of sugar beet seedlings by regulation of Cl− transport under NaCl stress, which is possibly involved in upregulation of BvCLC-b, BvCLC-c and BvCLC-f genes encoding Cl− transporters in a cell wall-dependent Ca2+ signal transduction process.

Unique Regulation of Intestinal Villus Epithelial Cl-/HCO3- Exchange by Cyclooxygenase Pathway Metabolites of Arachidonic Acid in a Mouse Model of Spontaneous Ileitis.

Electrolytes (NaCl) and fluid malabsorption cause diarrhea in inflammatory bowel disease (IBD). Coupled NaCl absorption, mediated by Na+/H+ and Cl−/HCO3− exchanges on the intestinal villus cells brush border membrane (BBM), is inhibited in IBD. Arachidonic acid metabolites (AAMs) formed via cyclooxygenase (COX) or lipoxygenase (LOX) pathways are elevated in IBD. However, their effects on NaCl absorption are not known. We treated SAMP1/YitFc (SAMP1) mice, a model of spontaneous ileitis resembling human IBD, with Arachidonyl Trifluoro Methylketone (ATMK, AAM inhibitor), or with piroxicam or MK-886, to inhibit COX or LOX pathways, respectively. Cl−/HCO3− exchange, measured as DIDS-sensitive 36Cl uptake, was significantly inhibited in villus cells and BBM vesicles of SAMP1 mice compared to AKR/J controls, an effect reversed by ATMK. Piroxicam, but not MK-886, also reversed the inhibition. Kinetic studies showed that inhibition was secondary to altered Km with no effects on Vmax. Whole cell or BBM protein levels of Down-Regulated in Adenoma (SLC26A3) and putative anion transporter-1 (SLC26A6), the two key BBM Cl−/HCO3− exchangers, were unaltered. Thus, inhibition of villus cell Cl−/HCO3− exchange by COX pathway AAMs, such as prostaglandins, via reducing the affinity of the exchanger for Cl−, and thereby causing NaCl malabsorption, could significantly contribute to IBD-associated diarrhea.

Humic\u2009+\u2009Fulvic acid mitigated Cd adverse effects on plant growth, physiology and biochemical properties of garden cress

Cadmium (Cd) is a toxic and very mobile heavy metal that can be adsorbed and uptaken by plants in large quantities without any visible sign. Therefore, stabilization of Cd before uptake is crucial to the conservation of biodiversity and food safety. Owing to the high number of carboxyl and phenolic hydroxyl groups in their structure, humic substances form strong bonds with heavy metals which makes them perfect stabilizing agents. The aim of this study was to determine the effects of humic and fulvic acid (HA + FA) levels (0, 3500, 5250, and 7000 mg/L) on alleviation of Cadmium (Cd) toxicity in garden cress (Lepidium sativum) contaminated with Cd (CdSO4.8H2O) (0, 100, and 200 Cd mg/kg) under greenhouse conditions. Our results showed that, Cd stress had a negative effect on the growth of garden cress, decreased leaf fresh, leaf dry, root fresh and root dry weights, leaf relative water content (LRWC), and mineral content except for Cd, and increased the membrane permeability (MP) and enzyme (CAT, SOD and POD) activity. However, the HA + FA applications decreased the adverse effects of the Cd pollution. At 200 mg/kg Cd pollution, HA + FA application at a concentration of 7000 mg/L increased the leaf fresh, leaf dry, root fresh, root dry weights, stem diameter, leaf area, chlorophyll reading value (CRV), MP, and LRWC values by 262%, 137%, 550%,133%, 92%, 104%, 34%, 537%, and 32% respectively, compared to the control. Although the highest H2O2, MDA, proline and sucrose values were obtained at 200 mg/L Cd pollution, HA + FA application at a concentration of 7000 mg/L successfully alleviated the deleterious effects of Cd stress by decreasing H2O2, MDA, proline, and sucrose values by 66%, 68%, 70%, and 56%, respectively at 200 mg/kg Cd pollution level. HA + FA application at a concentration of 7000 mg/L successfully mitigated the negative impacts of Cd pollution by enhanced N, P, K, Ca, Mg, Fe, Mn, Cu, Mn, Zn, and B by 75%, 23%, 84%, 87%, 40%, 85%, 143%, 1%, 65%, and 115%, respectively. In addition, HA + FA application at a concentration of 7000 mg/L successfully reduced Cd uptake by 95% and Cl uptake by 80%. Considering the plant growth parameters, the best results were determined when HA + FA concentration was 7000 mg/L. We have shown that, it is critical to apply a humic substance with high percentage of FA, which was 10% in this study, to mitigate the adverse effects of heavy metal stress on plant growth. In conclusion, the application of HA + FA may be suggested as an effective solution for reducing the Cd uptake of the plants by stabilizing Cd in soil and preventing translocation of Cd from the roots of plant to its shoot and leaves.

Inoculation with Arbuscular mycorrhizae, Penicillium funiculosum and Fusarium oxysporum enhanced wheat growth and nutrient uptake in the saline soil

Soil salinity limits wheat growth, but several fungal species can promote the productivity under saline conditions. This study investigated how Arbuscular mycorrhizal fungi (AMF), and Penicillium funiculosum and Fusarium oxysporum (PFFO) affected wheat growth under saline conditions.Wheat, inoculated with AMF, or PFFO, or with AMF and PFFO, was stressed with 75, or 150 mM NaCl in the soil. AMF colonization, grain yield, shoot and root dry weights, nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), sodium (Na), and chloride (Cl), relative permeability, chlorophyll and proline contents and root malondialdehyde (MDA) were determined.Salinity limited the grain yield, and reduced N, P and K uptake and chlorophyll content. As soil salinity increased, shoot Na and Cl contents, relative permeability and proline content, and MDA increased. PFFO enhanced root colonization with AMF, N and P uptake and AMF significantly increased N, P and K uptake and chlorophyll content and decreased proline, Na, Cl and MDA contents. Compared to AMF, or PFFO, dual inoculation with AMF and PFFO decreased shoot Na and Cl uptake, increased chlorophyll, shoot N and P contents and K/Na ratio and resulted in approximately 25, 35 and 43% higher grain yield at 0, 75 and 150 mM NaCl, respectively.Data showed that Penicillium funiculosum and Fusarium oxysporum promoted AMF symbiotic effects and alleviated the deleterious effects of NaCl salts on wheat growth.

Antagonism of chloride and nitrate inhibits nitrate reductase activity in chloride-stressed maize

Chloride (Cl−) is required for photosynthesis and regulates osmotic balance. However, excess Cl− application negatively interacts with nitrate ({mathrm{NO}}_{3}^{-}) uptake, although its effect on {mathrm{NO}}_{3}^{-} metabolism remains unclear. The aim was to test whether Cl− stress disturbs nitrate reductase activity (NRA). A maize variety (Zea mays L. cv. LG 30215) was hydroponically cultured in a greenhouse under the following conditions: control (2 mM CaCl2), moderate Cl− (10 mM CaCl2), high Cl− (60 mM CaCl2). To substantiate the effect of Cl− stress further, an osmotic stress with lower intensity was induced by 60 g polyethylene glycol (PEG) 6000 L−1 + 2 mM CaCl2), which was 57% of the osmotic pressure being produced by 60 mM CaCl2. Results show that high Cl− and PEG-induced osmotic stress significantly reduced shoot biomass, stomatal conductance and transpiration rate, but NRA was only decreased by high Cl− stress. The interference of NRA in chloride-stressed maize is supposed to be primarily caused by the antagonistic uptake of Cl− and {mathrm{NO}}_{3}^{-}.