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Studies have shown that the stress tolerance of cereal plants to osmotic or salinity stresses can be improved to varying degrees by the overexpression of an introduced betaine aldehyde dehydrogenase (BADH) gene. In the present study, the HvBADH1 gene from Hordeum vulgare L. var. nudum Hook. f., encoding a cytosolic BADH, was transferred into Triticum aestivum via traditional Agrobacterium tumefaciens-mediated transformation. Molecular methods, such as PCR, Southern blot analysis, and real-time quantitative RT-PCR were used to identify the successful integration and expression of the HvBADH1 transgene in genetically transformed wheat lines. To detect the efficacy of the HvBADH1 transgene in the transformants, some pivotal physiological indicators that reflected abiotic stress tolerance were measured in individual transgenic plant lines. These indicators included intracellular K⁺ and Na⁺ contents or K⁺/Na⁺ ratio, relative conductivity, and malondialdehyde and glycine betaine (GB) concentrations in cells. The results revealed that all the tested transgenic lines could significantly increase the recruitments of K⁺ in their cytosol than the wild-type seedlings. Similarly, 11.59- to 21.82-fold greater accumulation of GB, 2.11–2.56 times higher calli relative growth rates, and 26.2–29.1% seedling survival rates were found in transgenic lines under 150 mM NaCl stressed conditions. Our results demonstrated that by overexpressing the HvBADH1 transgene in genetically transformed wheat, the overall salt tolerance of the target plants was significantly increased, and the damaging effects of high salinity were significantly reduced.
The national incidence of neonatal abstinence syndrome has dramatically increased over the last decade due to an increase in antenatal opioid exposure. Recent human and animal studies suggest that antenatal opioid exposure impacts the developing brain. The purpose of this study is to evaluate the effects of perinatal methadone exposure on myelination in multiple regions in the developing rat brain. Pregnant Sprague-Dawley rats were randomly assigned into three experimental groups and subsequently exposed to drinking water alone or drinking water containing methadone from 7 days post coitum through day 7 or through day 19 after delivery. Two male neonatal rats were randomly selected from each litter and terminated at day 19. The cerebral cortex, hippocampus, cerebellum, and brainstem were dissected and analyzed for three myelin specific proteins – CNP, PLP, and MBP – by Western blot analysis. All pups with exposure to methadone demonstrated decreased expression of CNP, PLP, and MBP in the cerebral cortex and hippocampus. In the cerebellum, PLP expression was down-regulated without apparent alteration of CNP and MBP expression. PLP and MBP expression, but not CNP expression, were significantly inhibited in the brainstem. Compared to the pups with postnatal methadone exposure via maternal milk through day 7, partial recovery of CNP and PLP expression only occurred in the cerebral cortices of the pups exposed through day 19. The findings show that antenatal opioid exposure in rat pups is associated with regionally-specific alterations in brain myelination that diversely affects myelin proteins.
Nitrogen (N), phosphorus (P), potassium (K), and magnesium (Mg) have essential physiological functions in plants. Their interactions in plants are not fully understood especially at the molecular level. In this study, we detected the physiological and molecular responses of rice plants at the vegetative growth phase to N, P, K, and Mg starvations. Deficiencies of N and P resulted in accumulation of soluble sugar and starch in the leaves. The root to shoot ratio increased under N and P deficiencies, but decreased under K and Mg deficiencies. In addition, deficiency of either K or Mg resulted in accumulation of the other cation in shoots. Moreover, K starvation decreased both K and soluble sugar contents in the roots pronouncedly. RT-PCR analysis showed that several sugar transporter genes in the leaves orchestrated with sugar accumulation induced by the nutrient shortages. Expression of a high affinity K transporter gene (OsHAK1) and a putative Mg transporter gene (OsMGT) showed opposite down- and up-regulation in the roots by K starvation. These findings suggest that deficiencies of the major nutrients suppressed the export of carbohydrates from source leaves. The regulated sugar and nutrient transporter genes investigated in this study could be used for elucidating the molecular mechanism of plants in their adaptation to varied nutrient supply.
hTERT (human telomerase reverse transcriptase) plays a key role in the process of cell immortalization. Overexpression of hTERT has been implicated in 85% of malignant tumors and offers a specific target for cancer therapy. In this paper, we describe an effective approach using a single-chain variable fragment (scFv) intrabody derived from monoclonal hybridoma directed against hTERT to attenuate the immortalization of human uterine cervix and hepatoma cells. The scFv we constructed had a high affinity to hTERT, and specifically neutralized over 70% of telomere synthesis activity, thereby inhibiting the viability and proliferation of the cancer cells. Our results indicate that this anti-hTERT intrabody is a promising tool to target hTERT and intervene in the immortalization process of cancer cells.
The distribution of and prediction models for heavy metals in wheat were evaluated in Tianjin, China. The results indicated that there were high heavy metal concentrations (Zn, Cd, Cu, Pb, Cr, and Ni) in the wheat and that the Cd concentration (0.062mg·kg-1) in the seeds actually exceeded the national safety standard. The accumulation factors for the wheat’s seeds were of a decreasing order: Zn>Cd>Cu>Pb>Cr>Ni. The Cd concentration in the wheat’s seeds corresponded closely with the Cd concentration in the soil (r = 0.74). The predicting model was appropriate for predicting the concentration of Cd and Zn in wheat, and the r was 0.735 and 0.625, respectively.
Excessive excitation or loss of inhibitory neurotransmission has been closely related to epileptic activity. Somatostatin (SST) and Neuropeptide Y (NPY) are members of endogenous neuropeptides which are recognized as important modulator of classical neurotransmitter, distributed abundantly in mammalian central nervous system. Abnormal expression of these two neuropeptides evidenced in some epileptic models highlights the relevance of SST or NPY in the pathogenesis of epilepsy. The tremor rat (TRM) is a genetic epileptic animal model which can manifest tonic convulsions without any external stimuli. The present study aimed to investigate the distribution and expression of SST and NPY in TRM brains, including hippocampus, temporal lobe cortex and cerebellum. Our RT‑PCR data showed that up‑regulated mRNA expression of SST and NPY was discovered in TRM hippocampus and temporal lobe cortex compared with control (Wistar) rats. The peptide levels of these neuropeptides in brain areas mentioned above were both apparently higher than that in normal Wistar rats as well. However, in cerebellums, neither SST nor NPY was significantly changed compared with control group. The immunohistochemical data showed that SST and NPY were widely present throughout CA1, CA3 and the hilus of hippocampus, the entorhinal cortex of temporal lobe cortex, as well as cerebellar Purkinje layer. In conclusion, our results discovered the aberrant changes of SST and NPY in several TRM brain regions, suggesting that the peptidergic system might be involved in TRM epileptiform activity.
Ecological risks of heavy metal toxicity such as Cd, Cu, Pb, Zn, Cr, As, and Hg through crops (wheat and rice) grown in the Tianjin sewage irrigation area in northern China were studied in this paper. Wheat and rice samples as well as related soil samples from 77 select blocks were collected. The second grade of standards for Tianjin soil environmental quality was used for soil risk assessment. Chinese National Food Safe Criterion was used for health risk assessment of wheat and rice grains. Daily intake rate and Target hazard quotient were used for the potential health risk assessment of local population through the intake of wheat and rice grown in the sewage-irrigated site. The results showed that continuous application of wastewater has led to accumulation of heavy metals in the soil, and Cd, Zn, and Hg were the main pollutants. Zn and Cd were more mobile than other metals. Pb in wheat and rice had an ecological risk to human health. As and Hg in some rice samples as well as Cd, Zn, and As in some wheat samples had potential risk. Target hazard quotient (THQ) of individual metal was below 1.0, meaning the relative absence of health risks associated with intake of a single heavy metal through intake of either wheat or rice. THQs of As for wheat and rice would sum up to above 1.0, indicating As may pose a risk to the local population by intake of wheat and rice.
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