Chromate (CrVI) is a highly phytotoxic contaminant that is ubiquitous in soils. However, how Cr(VI) is taken up by plant roots remains largely unknown. Here, we show that the high-affinity sulfate ...transporter Sultr1;2 is responsible for Cr(VI) uptake by the roots of Arabidopsis thaliana. Sultr1;2 showed a much higher transport activity for Cr(VI) than Sultr1;1 when expressed in yeast cells. Knockdown of Sultr1;2 expression in Arabidopsis markedly reduced the Cr(VI) uptake rate, whereas knockout of Sultr1;1 had no or little effect. A double-knockout mutant (DKO) of the two genes lost the ability of Cr(VI) uptake almost completely. The Sultr1;2 knockdown mutant or DKO plants displayed higher resistance to Cr(VI) under normal sulfate conditions as a consequence of the lower tissue Cr accumulation. Overexpression of Sultr1;2 substantially increased Cr(VI) uptake with shoot Cr concentration being 1.6–2.0 times higher than that in the wild-type. These results indicate that Sultr1;2 is a major transporter responsible for Cr(VI) uptake in Arabidopsis, while Sultr1;1 plays a negligible role. Taken together, our study has identified a major transporter for Cr(VI) uptake in plants, providing potential strategies for engineering plants with low Cr accumulation and consequently enhanced Cr(VI) resistance and also plants with enhanced accumulation of Cr for the purpose of phytoremediation.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Catalytic nitrite reductions by CuII complexes containing anionic Me2Tp, neutral Me2Tpm, or neutral iPrTIC ligands in the presence of l-ascorbic acid, which served as an electron donor and proton ...source, were investigated. The results showed that auxiliary ligands are important for copper-mediated catalytic nitrite reduction. Furthermore, the electronic effects of the ligand govern the nitrite reduction efficiency, which should be considered at two control points: one is the susceptibility of the LCuI-nitrite species to protonation and the other is the susceptibility of LCuII to reduction giving LCuI. In addition, an external strong acid leads to the production of nitrous acid, which may suggest that the reactivity of nitrous acid toward the LCuI species is a third control point.
Catalytic nitrite reductions by Cu
II
complexes containing anionic
Me2
Tp, neutral
Me2
Tpm, or neutral
i
Pr
TIC ligands in the presence of
l
-ascorbic acid, which served as an electron donor and ...proton source, were investigated. The results showed that auxiliary ligands are important for copper-mediated catalytic nitrite reduction. Furthermore, the electronic effects of the ligand govern the nitrite reduction efficiency, which should be considered at two control points: one is the susceptibility of the LCu
I
-nitrite species to protonation and the other is the susceptibility of LCu
II
to reduction giving LCu
I
. In addition, an external strong acid leads to the production of nitrous acid, which may suggest that the reactivity of nitrous acid toward the LCu
I
species is a third control point.
Catalytic nitrite reductions by Cu
II
complexes containing anionic
Me2
Tp, neutral
Me2
Tpm, or neutral
i
Pr
TIC ligands in the presence of
l
-ascorbic acid, which served as an electron donor and proton source, were investigated.
Arsenic (As) biovolatilization is an important component of the global As biogeochemical cycle. Soils can emit various methylarsine gases, but the underlying microbial processes remain unclear. Here, ...we show that the addition of molybdate (Mo), an inhibitor of sulfate-reducing bacteria, greatly enhanced dimethylarsine evolution from dimethylarsenate DMAs(V) added to two paddy soils. Molybdate addition significantly affected the microbial community structure. The aerobic enrichment cultures from both soils volatilized substantial amounts of dimethylarsine from DMAs(V) in the presence of Mo, whereas the anaerobic enrichment cultures did not. A Bacillus strain (CZ-2) capable of reducing DMAs(V) to dimethylarsine was isolated from the aerobic enrichment culture, and its volatilization ability was enhanced by Mo. RNA-seq analysis identified 10 reductase genes upregulated by Mo. Addition of the reducing agent NADH increased dimethylarsine volatilization by strain CZ-2, suggesting that DMAs(V) reductase is an NADH-dependent enzyme. The strain could not methylate arsenite or convert monomethylarsenate and DMAs(V) to trimethylarsine. Our results show that dimethylarsine evolution from DMAs(V) is independent of the As methylation pathway and that Mo enhances dimethylarsine evolution from paddy soils by shifting the microbial community structure and enhancing the reduction of DMAs(V) to dimethylarsine, possibly through upregulating the expression of DMAs(V) reductase gene(s).
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
A novel fluorescent chemosensor based on the oxadiazole, 2-(2-hydroxyphenyl)-5-(4-methoxyphenyl)-1,3,4-oxadiazole, was designed and synthesized. The interaction of the oxadiazole with different metal ...ions had been investigated through UV–vis absorption and fluorescence spectra in 9:1 (v/v) ethanol-water (pH=7.0) solution. The oxadiazole showed a pronounced fluorescence enhancement at 430nm upon addition of Zn2+ in aqueous solution, whereas it had no apparent interference from other metal ions. The results indicated that the oxadiazole possessed high selectivity and sensitivity to Zn2+ ion. The stoichiometric ratio between the oxadiazole and Zn2+ ion was calculated to be 2:1 by Job plot experiment, meanwhile their binding modes was confirmed by 1H NMR and mass spectrometry. Their association constant was determined to be 1.95×105M−1 and the detection limit for Zn2+ ion was 6.14×10−7mol/L.
Display omitted
•An oxadiazole derivative based fluorescent probe was synthesized.•The oxadiazole exhibited a highly selective fluorescence enhancement toward Zn2+.•The oxadiazole had good selectivity and sensitivity to Zn2+ in aqueous solutions.•The sensing property was monitored by UV–vis, fluorescence, 1H NMR and MS spectroscopy.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To understand the situation of intestinal nematode infections and assess the preventive effects, so as to provide the evidence for formulating the further measures of prevention.
Five villages from 5 ...townships of different geographical locations were selected and 500 residents of each village were surveyed. The eggs of intestinal nematodes were detected by the Kato-Katz technique, and 50 students and 50 residents per village were investigated by questionnaires about health education.
Among 3 011 people detected, 17 persons were infected with intestinal nematodes and the total infection rate was 0.56%. The rates of Ascaris lumbricoides, hookworm, Trichuris trichiura, Enterobius vermicularis, and Trichostrongylus were 0.10%, 0.33%, 0.03%, 0.03% and 0.07%, respectively. The awareness rate of health knowledge was 97.80% and the formation rate of health behavior was 97.00%.
The infection rates of intestinal nematodes, the awareness rate of health knowledge and the formation rate of health behavior in the populatio
Arachidonic acid (ArA) is important for human health because it is one of the major components of mammalian brain membrane phospholipids. The interest in ArA inspired the search for a new sustainable ...source, and the green microalga Myrmecia incisa Reisigl H4301 has been found a potential ArA-producer due to a high content of intracellular ArA. To gain more molecular information about metabolism pathways, including the biosynthesis of ArA in the non-model microalga, a transcriptomic analysis was performed.
The 454 pyrosequencing generated 371,740 high-quality reads, which were assembled into 51,908 unique sequences consisting of 22,749 contigs and 29,159 singletons. A total of 11,873 unique sequences were annotated through BLAST analysis, and 3,733 were assigned to Gene Ontology (GO) categories. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis uncovered a C4-like photosynthesis pathway in M. incisa. The biosynthesis pathways of lipid particularly those of ArA and triacylglycerol (TAG) were analyzed in detail, and TAG was proposed to be accumulated in oil bodies in the cytosol with the help of caleosin or oil globule-associated proteins. In addition, the carotenoid biosynthesis pathways are discussed.
This transcriptomic analysis of M. incisa enabled a global understanding of mechanisms involved in photosynthesis, de novo biosynthesis of ArA, metabolism of carotenoids, and accumulation of TAG in M. incisa. These findings provided a molecular basis for the research and possibly economic exploitation of this ArA-rich microalga.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pyrrolidine (PyD) has an important impact on the environment and human health. However, there is currently no method for trace detection of PyD. Here, we successfully designed ...diaminomethylene-4H-pyran (1) as the first specific fluorescent probe for PyD. Only by adding PyD to probe 1, there is blue fluorescence at 455 nm, and the color of the solution changes from colorless to yellow. The detection limit is 1.12 × 10−6 M, and the response time is less than 5 min. Meanwhile, probe 1 can also sense the gaseous PyD and detect PyD in actual water samples. Moreover, due to the low biological toxicity, probe 1 can detect the exogenous PyD in zebrafish. The preliminary mechanism shows that probe 1 and PyD undergo a combination-type chemical reaction to generate a new substance 1-PyD. Therefore, the 100% atom utilization reaction enables probe 1 to exhibit specific adsorption and removal of PyD.
Display omitted
•The first fluorescent probe sensing PyD in solution and gaseous states is reported•This specific probe 1 with low LOD and fast response can detect PyD by naked eye•Probe 1 with the multifunction of removing PyD can be used in actual water samples•The low cytotoxicity makes probe 1 applied to detect exogenous PyD in zebrafish
Natural sciences; Chemistry; Applied sciences.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
There is an active demand for full-color fluorophores in the field of fluorescent dyes. However, a core skeleton with a simple structure and easy modification is currently insufficient. Herein, we ...develop a range of full-color-tunable fluorophores
3a-3m
based on the fluorinated benzothiadiazole skeleton and their control compounds
3n-3p
. By regulating the charge transfer strength between donors and acceptors, the emission colors of
3a-3p
spanning from blue to red (
λ
em
= 445-672 nm) are achieved. Interestingly, compounds
3a-3p
with a fluorinated core skeleton exhibit sensitive solvatochromism effects, large Stokes shifts and excellent dual-state emission (especially
3c-3k
). Meanwhile, with the control of different substituents in the donor structure, ACQgens (
3a-3i
and
3n-3p
) can be facilely tuned to AIEEgens (
3j-3m
). Notably, red AIEEgen
3m
shows great potential for bioimaging in live cells with low cytotoxicity.
By modulating donor and acceptor units, serial fluorinated benzothiadiazole-based full-color fluorophores with various luminescence properties, such as DSE, ACQ and AIEE effects, are developed. Importantly, red emitter
3m
can be used in bioimaging.
Objective
To explore the optimal thermal effect parameter combination of An-pressing manipulation based on the pressing force, time and frequency, and to compare the thermal effect differences ...between the rhythmic and the continuous An-pressing manipulations.
Methods
Three levels of light, moderate and heavy pressing forces were determined according to the An-pressing forces of the clinical tuina physicians; the pressing time and frequency parameters were determined according to the literatures about An-pressing manipulation. The volunteers were stimulated by the homemade An-pressing manipulation stimulator on the right Xinshu (BL 15), and then the three-factor and three-level orthogonal tests were carried out according to the test sequence specified by the L
9
(3
4
) orthogonal table, and the temperature before and after pressing was recorded by an infrared thermal imaging system to screen the best parameters for the thermal effect of the An-pressing manipulation, thus to determine the optimal pressing parameters. The optimal parameters were then used for both continuous and rhythmic An-pressing manipulations to stimulate the bilateral Xinshu (BL 15). The temperature changes after pressing and the duration of the thermal effect (temperature difference ≤0.5 °C on both sides) were recorded by the infrared thermal imaging system, to explore the differences in the thermal effects of different An-pressing manipulations.
Results
Among the three factors of pressing force, time and frequency, the influences of different pressing forces on temperature were significantly different (
F
=32.843,
P
=0.030), and the influence of 2.5 kg pressing force was the most significant; the effects of different pressing time on temperature were significantly different (
F
=54.102,
P
=0.018), and the pressing time of 7.5 min was the most significant; the influences of different pressing frequencies on temperature were not statistically significant (
F
=2.181,
P
=0.314), though the influence of 10 times/min pressing frequency was the largest. The influences on temperature difference of the rhythmic and the continuous An-pressing manipulations were significantly different (
P
=0.031 on the left side and
P
=0.045 on the right side), but there was no statistical difference in the duration of the thermal effect (
P
=0.690).
Conclusion
The An-pressing manipulation parameters that significantly affect the temperature difference are pressing force and time. The optimal combination of thermal effect parameters is pressing force of 2.5 kg, time of 7.5 min, and frequency of 10 times/min. The local thermal effect of the rhythmic An-pressing manipulation is significantly greater than of the continuous An-pressing manipulation.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
PDF
