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The gut microbiome has been shown to regulate the development and functions of the enteric and central nervous systems. Its involvement in the regulation of behavior has attracted particular attention because of its potential translational importance in clinical disorders, however little is known about the pathways involved. We previously have demonstrated that administration of Lactobacillus rhamnosus (JB-1) to healthy male BALB/c mice, promotes consistent changes in GABA-A and -B receptor sub-types in specific brain regions, accompanied by reductions in anxiety and depression-related behaviors. In the present study, using magnetic resonance spectroscopy (MRS), we quantitatively assessed two clinically validated biomarkers of brain activity and function, glutamate+glutamine (Glx) and total N-acetyl aspartate+N-acetyl aspartyl glutamic acid (tNAA), as well as GABA, the chief brain inhibitory neurotransmitter. Mice received 1×109 cfu of JB-1 per day for 4weeks and were subjected to MRS weekly and again 4weeks after cessation of treatment to ascertain temporal changes in these neurometabolites. Baseline concentrations for Glx, tNAA and GABA were equal to 10.4±0.3mM, 8.7±0.1mM, and 1.2±0.1mM, respectively. Delayed increases were first seen for Glx (~10%) and NAA (~37%) at 2weeks which persisted only to the end of treatment. However, Glx was still elevated 4weeks after treatment had ceased. Significantly elevated GABA (~25%) was only seen at 4weeks. These results suggest specific metabolic pathways in our pursuit of mechanisms of action of psychoactive bacteria. They also offer through application of standard clinical neurodiagnostic techniques, translational opportunities to assess biomarkers accompanying behavioral changes induced by alterations in the gut microbiome. •We have shown for the first time that the concentrations of certain metabolites increase in the brain following oral treatment with L. rhamnosus and do so with distinct kinetics.•Both tNAA and Glx increased relatively early after the start of L. rhamnosus die, while GABA was only elevated at four weeks.•These results suggest beneficial bacteria may alter brain function and offer translational approaches into the clinical setting.

Summary Stone cells are often present in pear fruit, and they can seriously affect the fruit quality when present in large numbers. The plant growth regulator NAA, a synthetic auxin, is known to play an active role in fruit development regulation. However, the genetic mechanisms of NAA regulation of stone cell formation are still unclear. Here, we demonstrated that exogenous application of 200 μM NAA reduced stone cell content and also significantly decreased the expression level of PbrNSC encoding a transcriptional regulator. PbrNSC was shown to bind to an auxin response factor, PbrARF13. Overexpression of PbrARF13 decreased stone cell content in pear fruit and secondary cell wall (SCW) thickness in transgenic Arabidopsis plants. In contrast, knocking down PbrARF13 expression using virus‐induced gene silencing had the opposite effect. PbrARF13 was subsequently shown to inhibit PbrNSC expression by directly binding to its promoter, and further to reduce stone cell content. Furthermore, PbrNSC was identified as a positive regulator of PbrMYB132 through analyses of co‐expression network of stone cell formation‐related genes. PbrMYB132 activated the expression of gene encoding cellulose synthase (PbrCESA4b/7a/8a) and lignin laccase (PbrLAC5) binding to their promotors. As expected, overexpression or knockdown of PbrMYB132 increased or decreased stone cell content in pear fruit and SCW thickness in Arabidopsis transgenic plants. In conclusion, our study shows that the ‘PbrARF13‐PbrNSC‐PbrMYB132’ regulatory cascade mediates the biosynthesis of lignin and cellulose in stone cells of pear fruit in response to auxin signals and also provides new insights into plant SCW formation.

Fruit drop from pear trees causes serious losses in income. However, the application of plant bio-regulators improves the internal physiology of developing fruit by ensuring that they receive an adequate supply of water, nutrients, and other compounds necessary for their proper growth and development, which leads to improved size, quality, and ultimately better yield in a variety of fruit crops. This study investigated the foliar application of three plant growth regulators: CPPU at 10, 15, and 20 ppm, GA3 at 25, 50, and 75 ppm and NAA at 25, 50, and 75 ppm. The pear trees were sprayed four times: before flowering, full bloom, after three weeks, and after six weeks. The results showed that the spray of GA3 at 50 and 75 ppm gave the highest effect in increasing the shoot length, shoot thickness, leaf area, and leaf total chlorophyll. The spraying of NAA at 50 and 75 ppm was the best treatment in increasing the fruit set percentages, fruit yield, fruit weight, and fruit dimensions as well as the fruit content from soluble solids, and fruit sugars, while they reduced the fruit drop percentages comparing with the other applied treatments.

Yam (Dioscorea species) has long been cultivated in Ethiopia, where farmers rely on conventional propagation using whole tuber seeds. This leads to a scarcity of clean tuber seeds, which limits production. This study aimed to optimize in vitro propagation and micro-tuberization protocols for the ‘Hatiye’ landrace, which focused on in vitro propagation, including shoot initiation, multiplication, and rooting, and micro-tuberization using MS medium supplemented with different concentrations of plant growth regulators. Experiments were arranged in a completely randomized design with three replications, using nodal segments as explants. For shoot initiation, four levels of α-naphthalene acetic acid (NAA) were combined with four levels of 6-benzylaminopurine (BAP). The highest shoot initiation (99.9%) and shortest initiation period (6.67 days) were obtained with 0.25 mg/L NAA and 1.0 mg/L BAP. During multiplication, seven MS medium treatments with different BAP levels were tested, while rooting was assessed with six NAA concentrations. The highest rooting percentage (99.9%), root number (9.67), and root length (9.5 cm) were recorded at 2 mg/L NAA. For microtuberization, MS medium with two BAP levels (0 and 2 mg/L) combined with five sucrose concentrations was tested under 10/14 light/dark hours. The highest number of microtubers (2.5) and longest microtuber lengths (1.67 mm and 1.23 mm) were achieved with 2 mg/L BAP and 60 g/L sucrose. This study provides a reliable protocol for in vitro propagation and micro-tuberization of the Hatiye yam landrace, addressing the shortage of clean tuber seeds and supporting yam production in Ethiopia.

•MR spectroscopic data was collected in the calcarine of 187 healthy aging adults.•GABA+ and Glx levels decreased with increasing age from 19 to 79 years-old.•Glx/GABA+ ratio also declined with increasing age, indicating disrupted E/I balance.•Age-related decreases in tNAA and increases in tCr, with no change in mI or tCho.•Age may affect neuro-physiology and -chemistry more than structure in visual cortex. Aging has been associated with widespread alterations in neural structure and function, but the underlying biochemical changes remain less understood despite recent neurophysiological work suggesting age-related alterations in the excitatory/inhibitory (E/I) balance. In the current study, we used ¹H-MRS to quantify levels of excitatory (Glx: glutamate + glutamine) and inhibitory (GABA+: GABA + macromolecules) neurotransmitters in the calcarine cortex in 187 healthy adults (19–79 years-old). These neurotransmitter estimates were used to compute the E/I ratio, and all three parameters were examined for aging effects. Given our large sample, we also conducted supplementary analyses to estimate the concentration of secondary metabolites commonly implicated in aging, including total creatine (tCr), total N-acetyl aspartate (tNAA), total choline (tCho), and myo-inositol (mI). Following best practices, metabolite concentrations were estimated relative to the unsuppressed water signal and corrected for voxel tissue composition (i.e., gray matter, white matter, CSF). Our results indicated significant age-related declines in both GABA+ and Glx, along with a reduction in the E/I ratio, suggesting diminished inhibitory and excitatory tone with advancing age. We also found a decline in tNAA and an increase in tCr with increasing age. In summary, we provide compelling evidence through one of the largest studies of its kind for age-related shifts in excitatory and inhibitory neurotransmitter levels in the visual cortex. These changes may be critical to well-known, age-related physiological changes, including reduced neural selectivity and processing efficiency. These findings provide novel evidence that neurochemical alterations may contribute to the functional declines in cortical processing seen in healthy aging.

We investigated glutamate-related neuronal dysfunction in the anterior cingulate (AC) early in schizophrenia before and after antipsychotic treatment. A total of 14 minimally treated schizophrenia patients and 10 healthy subjects were studied with single-voxel proton magnetic resonance spectroscopy (¹H-MRS) of the AC, frontal white matter and thalamus at 4T. Concentrations of N-acetylaspartate (NAA), glutamate (Glu), glutamine (Gln) and Gln/Glu ratios were determined and corrected for the partial tissue volume. Patients were treated with antipsychotic medication following a specific algorithm and ¹H-MRS was repeated after 1, 6 and 12 months. There were group x region interactions for baseline NAA (P = 0.074) and Gln/Glu (P = 0.028): schizophrenia subjects had lower NAA (P = 0.045) and higher Gln/Glu (P = 0.006) in the AC before treatment. In addition, AC Gln/Glu was inversely related to AC NAA in the schizophrenia (P = 0.0009) but not in the control group (P = 0.92). Following antipsychotic treatment, there were no further changes in NAA, Gln/Glu or any of the other metabolites in any of the regions studied. We conclude that early in the illness, schizophrenia patients already show abnormalities in glutamatergic metabolism and reductions in NAA consistent with glutamate-related excitotoxicity.

•TMS and MRS reveal complementary and comprehensive information on neurotransmission.•TMS-MRS combinations can uncover healthy and pathological brain functionality.•Repetitive TMS can modulate metabolite levels.•TMS-MRS combinations may probe connectivity and dedicated network interactions. Over the last decade, there has been an increasing number of studies combining transcranial magnetic stimulation (TMS) and magnetic resonance spectroscopy (MRS). MRS provides a manner to non-invasively investigate molecular concentrations in the living brain and thus identify metabolites involved in physiological and pathological processes. Particularly the MRS-detectable metabolites glutamate, the major excitatory neurotransmitter, and gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter, are of interest when combining TMS and MRS. TMS is a non-invasive brain stimulation technique that can be applied either as a neuromodulation or neurostimulation tool, specifically targeting glutamatergic and GABAergic mechanisms. The combination of TMS and MRS can be used to evaluate alterations in brain metabolite levels following an interventional TMS protocol such as repetitive TMS (rTMS) or paired associative stimulation (PAS). MRS can also be combined with a variety of non-interventional TMS protocols to identify the interplay between brain metabolite levels and measures of excitability or receptor-mediated inhibition and facilitation. In this review, we provide an overview of studies performed in healthy and patient populations combining MRS and TMS, both as a measurement tool and as an intervention. TMS and MRS may reveal complementary and comprehensive information on glutamatergic and GABAergic neurotransmission. Potentially, connectivity changes and dedicated network interactions can be probed using the combined TMS-MRS approach. Considering the ongoing technical developments in both fields, combined studies hold future promise for investigations of brain network interactions and neurotransmission.

The present work deals with the hydrothermal synthesis of a Na-A (LTA) zeolite using rice husk as a starting material. The focus was on defining the most favorable conditions for the synthesis of zeolite Na-A from rice husk in order to economize on both energy (i.e., synthesis temperatures) and reaction time and to enlarge the field of the pure and isolated synthesized phase. Four sets of experiments were carried out at environmental pressure temperatures varying from 40 °C to 85 °C with a SiO2/Al2O3 ratio from 1.75 to 3.5. Optimal conditions for crystallization of the Na-A zeolite from rice husk were reached at 60 °C with a SiO2/Al2O3 ratio of 1.75. Sixty degrees Celsius represents the minimum known temperature used for the synthesis of NaA zeolite from rice husk. The products of synthesis were characterized by X-ray diffraction, scanning electron microscopy, infrared and Raman spectroscopy. The purity of the synthesized zeolite is verified here for the first time through quantitative phase analysis using the combined Rietveld and reference intensity ratio methods.

The mode of action of auxin is based on its non-uniform distribution within tissues and organs. Despite the wide use of several auxin analogues in research and agriculture, little is known about the specificity of different auxin-related transport and signalling processes towards these compounds. Using seedlings of Arabidopsis thaliana and suspension-cultured cells of Nicotiana tabacum (BY-2), the physiological activity of several auxin analogues was investigated, together with their capacity to induce auxin-dependent gene expression, to inhibit endocytosis and to be transported across the plasma membrane. This study shows that the specificity criteria for different auxin-related processes vary widely. Notably, the special behaviour of some synthetic auxin analogues suggests that they might be useful tools in investigations of the molecular mechanism of auxin action. Thus, due to their differential stimulatory effects on DR5 expression, indole-3-propionic (IPA) and 2,4,5-trichlorophenoxy acetic (2,4,5-T) acids can serve in studies of TRANSPORT INHIBITOR RESPONSE 1/AUXIN SIGNALLING F-BOX (TIR1/AFB)-mediated auxin signalling, and 5-fluoroindole-3-acetic acid (5-F-IAA) can help to discriminate between transcriptional and nontranscriptional pathways of auxin signalling. The results demonstrate that the major determinants for the auxin-like physiological potential of a particular compound are very complex and involve its chemical and metabolic stability, its ability to distribute in tissues in a polar manner and its activity towards auxin signalling machinery.

Background Tea plant breeding or cultivation mainly involves propagation via cuttings, which not only ensures the inheritance of the excellent characteristics of the mother plant but also facilitates mechanized management. The formation of adventitious root (AR) determines the success of cutting-based propagation, and auxin is an essential factor involved in this process. To understand the molecular mechanism underlying AR formation in nodal tea cuttings, transcriptome and endogenous hormone analysis was performed on the stem bases of red (mature)- and green (immature)-stem cuttings of ‘Echa 1 hao’ tea plant as affected by a pulse treatment with naphthalene acetic acid (NAA). Results In this study, NAA significantly promoted AR formation in both red- and green-stem cuttings but slightly reduced callus formation. External application of NAA reduced the levels of endogenous indole-3-acetic acid (IAA) and cytokinin (TZR, trans-zeatin riboside). The number of DEGs (NAA vs. CK) identified in the green-stem cuttings was significantly higher than that in the red-stem cuttings, which corresponded to a higher rooting rate of green-stem cuttings under the NAA treatment. A total of 82 common DEGs were identified as being hormone-related and involved in the auxin, cytokinin, abscisic acid, ethylene, salicylic acid, brassinosteroid, and jasmonic acid pathways. The negative regulation of NAA-induced IAA and GH3 genes may explain the decrease of endogenous IAA. NAA reduced endogenous cytokinin levels and further downregulated the expression of cytokinin signalling-related genes. By the use of weighted gene co-expression network analysis (WGCNA), several hub genes, including three [cellulose synthase ( CSLD2 ), SHAVEN3-like 1 ( SVL1 ), SMALL AUXIN UP RNA ( SAUR21 )] that are highly related to root development in other crops, were identified that might play important roles in AR formation in tea cuttings. Conclusions NAA promotes the formation of AR of tea cuttings in coordination with endogenous hormones. The most important endogenous AR inductor, IAA, was reduced in response to NAA. DEGs potentially involved in NAA-mediated AR formation of tea plant stem cuttings were identified via comparative transcriptome analysis. Several hub genes, such as CSLD2 , SVL1 and SAUR21 , were identified that might play important roles in AR formation in tea cuttings.