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Cadmium (Cd) is among the world's major health concerns, as it renders soils unsuitable and unsafe for food and feed production. Phytoremediation has the potential to remediate Cd-polluted soils, but efforts are still needed to develop a deep understanding of the processes underlying it. In this study, we performed a comprehensive analysis of the root response to Cd stress in A. thaliana , which can phytostabilize Cd, and in A. halleri , which is a Cd hyperaccumulator. Suitable RNA-seq data were analyzed by WGCNA to identify modules of co-expressed genes specifically associated with Cd presence. The results evidenced that the genes of the hyperaccumulator A. halleri mostly associated with the Cd presence are finely regulated (up- and downregulated) and related to a general response to chemical and other stimuli. Additionally, in the case of A. thaliana , which can phytostabilize metals, the genes upregulated during Cd stress are related to a general response to chemical and other stimuli, while downregulated genes are associated with functions which, affecting root growth and development, determine a deep modification of the organ both at the cellular and physiological levels. Furthermore, key genes of the Cd-associated modules were identified and confirmed by differentially expressed gene (DEG) detection and external knowledge. Together, key functions and genes shed light on differences and similarities among the strategies that the plants use to cope with Cd and may be considered as possible targets for future research.

Aim: Different experimental approaches have demonstrated that children with sleep breathing disorders (SBD) exhibit neurocognitive and behavioural impairment. The present systematic review and meta-analysis aims to quantify neurocognitive deficit disorders in mouth breathing paediatric patients by summarising relevant case-controls studies. Neurocognitive assessment was undertaken with WISC., Methods: A search strategy was developed on electronic databases including Medline (Pubmed), Scopus, Scileo; Cochrane library from 2000 to June 2022 for published studies analysing neurocognitive skills in children with SBD compared to healthy control groups. The review was performed according to the PRISMA protocol and articles were selected according to the established inclusion and exclusion criteria. The Weighted Mean Differences (95% Confidence Intervals) were calculated between results obtained in WISC tests in SBD patients and healthy subjects., Conclusion: Our results confirmed that SBD affected children performed worse than healthy children in terms of quite all the cognitive domains investigated.

To improve the efficiency and applicability of the washing pre-treatment for combustion, pyrolysis and gasification, a modified approach was developed in the present study. Two novel washing approaches were tested using wheat straw and empty fruit bunches of oil palm: multiple-step washing with fresh water (SWFW) and wastewater recirculation (SWWR). SWFW showed the high removal of K (<68%), Cl (<99%), S (<80%), N (<58%), and ash (<52%) reducing fouling, slagging, and corrosion propensity of the biomass. Furthermore, with one-third the amount of water used in SWFW, SWWR showed similar to higher efficiency than SWFW with relatively better energy (98%) yields. Industrial-scale pilot testing was also conducted for the validation of the SWWR approach, which showed similar findings as the lab-scale results. The effect of a high washing temperature and pressing on washing efficiency and characterisation of wastewater was also determined. Overall, SWWR with pressing is recommended for industrial applications., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

In vivo, feeding stimulates and starvation inhibits transcription of the malic enzyme gene. In chick-embryo hepatocytes in culture, triiodothyronine (T3) stimulates and glucagon inhibits transcription of this gene. As a first step in the characterization of the involved regulatory mechanisms, fragments of genomic DNA spanning the structural and 5'-flanking regions of the chicken malic enzyme gene were cloned. The coding region of the gene is organized into 14 exons and 13 introns and is greater than 106 kb in length. The size of the gene, the number and lengths of the exons, and positions at which introns are inserted into the coding regions are virtually identical in the chicken and rat genes. When transiently transfected into chick-embryo hepatocytes, 5800 bp of 5'-flanking DNA conferred T3 responsiveness to a linked chloramphenicol acetyltransferase (CAT) reporter gene. Using deletion and site-specific mutations of 5'-flanking DNA, we identified a complex T3 response unit that contains one major T3 response element (T3RE) and several minor ones. The major element contains two degenerate copies of the hexamer, RGGWMA, separated by 4 bp and was a strong repressor in the absence of ligand. Endogenous levels of T3 receptor are sufficient to allow the T3 response elements in the upstream region of the malic enzyme gene to confer responsiveness to T3, suggesting that they are physiologically relevant.

We have provided a historical and personal description of the analysis of physiological and molecular mechanisms by which diet and hormones regulate the activity of hepatic malic enzyme. For the most part, our analyses have been reductionist in approach, striving for increasingly simpler systems in which we can ask more direct questions about the molecular nature of the signaling pathways that regulate the activity of malic enzyme. The reductionist approaches that were so successful at analyzing molecular mechanisms in cells in culture may now provide the means to analyze more definitively questions about the physiological mechanisms involved in nutritional regulation of gene expression. In addition to physiological questions, however, there are still many aspects of the molecular mechanisms that have not been elucidated. Despite considerable effort from many laboratories, the molecular mechanisms by which T3 regulates transcription are not clear. Similarly, the molecular details for the mechanisms by which glucagon, insulin, glucocorticoids, and fatty acids regulate gene expression remain to be determined. The role of fatty acids is particularly interesting because it may provide a model for mechanisms by which genes are regulated by metabolic intermediates; this is a form of transcriptional regulation widely used by prokaryotic organisms and extensively analyzed in prokaryotic systems, but poorly understood in higher eukaryotes. At any specific time, there is, of course, only one rate of transcription for each copy of the malic-enzyme gene in a cell. Our long-term objective is to understand how signals from all of the relevant regulatory pathways are integrated to bring about that rate.

The catalytic (C) subunit of cAMP-dependent protein kinase is inhibited by the regulatory (R) subunit and by a thermostable inhibitor (PKI). Both inhibitors also affect the intracellular distribution of the C subunit. Whether injected into the cytoplasm or into the nucleus, free C subunit can enter and exit the nucleus freely. After 30 min its distribution is identical and is independent of the initial site of injection. In contrast, when C is injected into the cytoplasm complexed with R or PKI, the complexes are restricted to the cytoplasm (1-3). However, unlike the R subunit, which is restricted to the cytoplasm like the holoenzyme, free PKI enters the nucleus rapidly following its injection into the cytoplasm. When holoenzyme is injected directly into the nucleus, it cannot exit and return to the cytoplasm. In contrast, nuclear injection of a C.PKI complex results in the rapid exit of the C subunit from the nucleus. In equilibrated cells previously injected with the C subunit, subsequent cytoplasmic injection of either PKI or type 1 R depletes the nucleus of C although PKI does so faster, consistent with its ability to enter the nucleus. Both inhibitors block the cAMP response element-regulated gene expression. Hence PKI may serve as a nuclear scavenger of C providing a mechanism not only for inhibition but also for subcellular localization in the presence of cAMP by restricting the access of the C subunit to the nucleus.

Temporal cellular events responsible for hormonal activation of responses mediated by the cAMP-dependent protein kinase (PKA) have been studied in living cells. By selectively perturbing molecular function of Gs, the catalytic subunit of PKA (C), or the nuclear factor CREB, in cells through microinjection of inhibitory agents specific for these molecules or activated forms of these molecules, we have obtained evidence for a requirement for the function of each of these molecules in the hormonal stimulation of cAMP-regulated genes. Moreover, by introducing fluorescently labeled PKA subunits into these cells as molecular tracers, or by immunofluorescence of C subunit, we have observed biological translocation of C subunit from the cytoplasm to the nucleus during transcriptional activation and a quenching of this by the inhibitor molecule, PKI. The implications of these cellular and molecular events in the signal transduction of hormonal responses are discussed.

cAMP-dependent protein kinase mediates a variety of cellular responses in most eukaryotic cells. Many of these responses are cytoplasmic, whereas others appear to require nuclear localization of the catalytic subunit. In order to understand further the molecular basis for subcellular localization of the catalytic subunit, the effect of the heat stable protein kinase inhibitor (PKI) was investigated. The subcellular localization of the catalytic (C) subunit was determined both in the presence and absence of PKI, by microinjecting fluorescently labeled C subunit into single living cells. When injected alone, a significant fraction of the dissociated C subunit localized to the nucleus. When coin-injected with an excess of PKI, little of the C subunit localized to the nucleus, suggesting that accumulation of catalytic subunit in the nucleus requires either enzymatic activity or a nuclear localization signal. Inactivation of the catalytic subunit in vitro by treatment with N-ethylmaleimide did not prevent localization in the nucleus, indicating that enzymatic activity was not a prerequisite for nuclear localization. In an effort to search for a specific signal that might mediate nuclear localization, a complex of the catalytic subunit with a 20-residue inhibitory peptide derived from PKI (PKI(5-24)) was microinjected. In contrast to intact PKI, the peptide was not sufficient to block nuclear accumulation. In the presence of PKI(5-24), the C subunit localized to the nucleus in a fashion analogous to that of dissociated, active C subunit despite evidence of no catalytic activity in situ. Thus, nuclear localization of the C subunit appears to be independent of enzymatic activity but most likely dependent upon a signal. The signal is apparently masked by both the regulatory subunit and PKI but not by the inhibitory peptide.

Sensitive immunochemical assays were used to measure the mass and rate of synthesis of malic enzyme protein in wild-type and Mod-1n mutant mice fed a high carbohydrate/low fat diet supplemented with thyroid hormone. Malic enzyme activity in the fed, wild-type mice was 100-fold higher than in starved, wild-type mice. Neither activity, mass, nor synthesis of malic enzyme could be detected in fed, mutant mice. However, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase responded to these dietary manipulations with normal or supranormal increases in activities, respectively, in mutant mice. A cDNA clone containing an almost complete copy of the mRNA for malic enzyme from duck liver was used to analyze poly(A+) RNA from C57BL/6J-DBA/2J hybrid mice that had been fasted and refed a high carbohydrate/low fat diet supplemented with thyroid hormone. The 32P-cDNA probe hybridized to two RNAs of 2250 and 2950 nucleotides. The same two RNAs were detected in RNA from starved mice except at much lower concentrations. A similar analysis of RNA from Mod-1n mice fed the high carbohydrate-thyroid diet also revealed two hybridizing RNAs but each was 700-800 nucleotides longer than its counterpart in wild-type mice. The abundance of malic enzyme mRNA in the fed, mutant mice was about the same as that in fed, wild-type mice. The mutant malic enzyme mRNAs also were present in RNA from starved mice but at much lower concentrations. These results suggest that the mutation responsible for the Mod-1n phenotype is in the structural gene for malic enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)