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PloS One 2020Transcriptomic responses of plants to weed presence gives insight on the physiological and molecular mechanisms involved in the stress response. This study evaluated...
Teosinte (Zea mays ssp parviglumis) growth and transcriptomic response to weed stress identifies similarities and differences between varieties and with modern maize varieties.
Transcriptomic responses of plants to weed presence gives insight on the physiological and molecular mechanisms involved in the stress response. This study evaluated transcriptomic and morphological responses of two teosinte (Zea mays ssp parviglumis) (an ancestor of domesticated maize) lines (Ames 21812 and Ames 21789) to weed presence and absence during two growing seasons. Responses were compared after 6 weeks of growth in Aurora, South Dakota, USA. Plant heights between treatments were similar in Ames 21812, whereas branch number decreased when weeds were present. Ames 21789 was 45% shorter in weedy vs weed-free plots, but branch numbers were similar between treatments. Season-long biomass was reduced in response to weed stress in both lines. Common down-regulated subnetworks in weed-stressed plants were related to light, photosynthesis, and carbon cycles. Several unique response networks (e.g. aging, response to chitin) and gene sets were present in each line. Comparing transcriptomic responses of maize (determined in an adjacent study) and teosinte lines indicated three common gene ontologies up-regulated when weed-stressed: jasmonic acid response/signaling, UDP-glucosyl and glucuronyltransferases, and quercetin glucosyltransferase (3-O and 7-O). Overall, morphologic and transcriptomic differences suggest a greater varietal (rather than a conserved) response to weed stress, and implies multiple responses are possible. These findings offer insights into opportunities to define and manipulate gene expression of several different pathways of modern maize varieties to improve performance under weedy conditions.
Topics: Gene Expression Regulation, Plant; Gene Ontology; Light; Photosynthesis; Plant Weeds; Stress, Physiological; Transcriptome; Zea mays
PubMed: 32822374
DOI: 10.1371/journal.pone.0237715 -
BioRxiv : the Preprint Server For... Jun 2024A better understanding of nicotine neurobiology is needed to reduce or prevent chronic addiction, ameliorate the detrimental effects of nicotine withdrawal, and increase...
A better understanding of nicotine neurobiology is needed to reduce or prevent chronic addiction, ameliorate the detrimental effects of nicotine withdrawal, and increase successful cessation of use. Nicotine binds and activates two astrocyte-expressed nicotinic acetylcholine receptors (nAChRs), α4β2 and α7. We recently found that ( or ) expression is restricted to astrocytes in mice and humans. To determine if AKT2 plays a role in astrocytic nicotinic responses, we generated astrocyte-specific conditional knockout (cKO) and full KO mice for and experiments. For studies, we examined mice exposed to chronic nicotine for two weeks in drinking water (200 μg/mL) and following acute nicotine challenge (0.09, 0.2 mg/kg) after 24 hrs. Our studies used cultured mouse astrocytes to measure nicotine-dependent astrocytic responses. We validated our approaches using lipopolysaccharide (LPS) exposure inducing astrogliosis. Sholl analysis was used to measure glial fibrillary acidic protein responses in astrocytes. Our data show that wild-type (WT) mice exhibit increased astrocyte morphological complexity during acute nicotine exposure, with decreasing complexity during chronic nicotine use, whereas cKO mice showed increased astrocyte morphology complexity. In culture, we found that 100μM nicotine was sufficient for morphological changes and blocking α7 or α4β2 nAChRs prevented observed morphologic changes. Finally, we performed conditioned place preference (CPP) in cKO mice and found that astrocytic AKT2 deficiency reduced nicotine preference compared to controls. These findings show the importance of nAChRs and signaling in the astrocytic response to nicotine.
PubMed: 38854016
DOI: 10.1101/2024.05.31.596856 -
Biochimica Et Biophysica Acta. General... Aug 2018Paclitaxel, a widely used antimicrotubular agent, predominantly eliminates rapidly proliferating cancer cells, while slowly proliferating and quiescent cells can survive...
Paclitaxel, a widely used antimicrotubular agent, predominantly eliminates rapidly proliferating cancer cells, while slowly proliferating and quiescent cells can survive the treatment, which is one of the main reasons for tumor recurrence and non-responsiveness to the drug. To improve the efficacy of chemotherapy, biomarkers need to be developed to enable monitoring of tumor responses. In this study we considered the auto-fluorescent metabolic cofactors NAD(P)H and FAD as possible indicators of cancer cell response to therapy with paclitaxel. It was found that, among the tested parameters (the fluorescence intensity-based redox ratio FAD/NAD(P)H, and the fluorescence lifetimes of NAD(P)H and FAD), the fluorescence lifetime of NAD(P)H is the most sensitive in tracking the drug response, and is capable of indicating heterogeneous cellular responses both in cell monolayers and in multicellular tumor spheroids. We observed that metabolic reorganization to a more oxidative state preceded the morphological manifestation of cell death and developed faster in cells that were more responsive to the drug. Our results suggest that noninvasive, label-free monitoring of the drug-induced metabolic changes by noting the NAD(P)H fluorescence lifetime is a valuable approach to characterize the responses of cancer cells to anti-cancer treatments and, therefore, to predict the effectiveness of chemotherapy.
Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Biomarkers; Flavin-Adenine Dinucleotide; Humans; Microscopy, Fluorescence, Multiphoton; NADP; Neoplasms; Oxidation-Reduction; Paclitaxel; Tumor Cells, Cultured
PubMed: 29719197
DOI: 10.1016/j.bbagen.2018.04.021 -
Journal of Cellular and Molecular... Feb 2009The heart is the main target organ of the parasite Trypanosoma cruzi, the causal agent of Chagas' disease, a significant public health issue and still a major cause of... (Review)
Review
The heart is the main target organ of the parasite Trypanosoma cruzi, the causal agent of Chagas' disease, a significant public health issue and still a major cause of morbidity and mortality in Latin America. During the acute disease, tissue damage in the heart is related to the intense myocardium parasitism. To control parasite multiplication, cells of the monocytic lineage are highly mobilized. In response to inflammatory and immune stimulation, an intense migration and extravasation of monocytes occurs from the bloodstream into heart. Monocyte differentiation leads to the formation of tissue phagocytosing macrophages, which are strongly activated and direct host defence. Newly elicited monocyte-derived macrophages both undergo profound physiological changes and display morphological heterogeneity that greatly differs from originally non-inflammatory macrophages, and underlie their functional activities as potent inflammatory cells. Thus, activated macrophages play a critical role in the outcome of parasite infection. This review covers functional and ultrastructural aspects of heart inflammatory macrophages triggered by the acute Chagas' disease, including recent discoveries on morphologically distinct, inflammation-related organelles, termed lipid bodies, which are actively formed in vivo within macrophages in response to T. cruzi infection. These findings are defining a broader role for lipid bodies as key markers of macrophage activation during innate immune responses to infectious diseases and attractive targets for novel anti-inflammatory therapies. Modulation of macrophage activation may be central in providing therapeutic benefits for Chagas' disease control.
Topics: Animals; Cell Movement; Cell Shape; Chagas Disease; Heart; Humans; Inflammation; Macrophage Activation; Macrophages; Monocytes; Myocardium; Phagocytosis; Trypanosoma cruzi
PubMed: 18624767
DOI: 10.1111/j.1582-4934.2008.00388.x -
Neuropsychobiology 1993The nervous system can generate outflow capable of signaling cells of the immune system via two routes: (1) hormonal influences via hypothalamopituitary-target organ... (Review)
Review
The nervous system can generate outflow capable of signaling cells of the immune system via two routes: (1) hormonal influences via hypothalamopituitary-target organ activation, and (2) neurotransmitter influences via direct innervation of the parenchyma of both primary and secondary lymphoid organs. Both noradrenergic and neuropeptidergic nerve fibers are found directly adjacent to cells of the immune system in bone marrow, thymus, spleen, lymph nodes, and other sites. These neurotransmitters can modulate immune responsiveness at several levels, including individual cellular functions, collective cellular interactions and immune responses, and overall host immunological response to a challenge by bacteria, viruses, tumor cells, or other sources. The ability of neural signals to modulate immune responsiveness is influenced by such factors as co-localization with other neurotransmitters, synergistic or dual signaling by neurotransmitters and cytokines, hormonal influences on ligand availability or receptor responsiveness, extent of catabolism and inactivation of the neural signal, and unique chemical and morphological aspects of the specific compartmentation of the lymphoid organ in which signaling is taking place. Thus, neural-immune signaling is a complex and dynamic process, with bidirectional interactions in a complex microenvironment.
Topics: Animals; Humans; Immune System; Lymphatic System; Neurotransmitter Agents; Signal Transduction
PubMed: 7902965
DOI: 10.1159/000119011 -
Nanoscale Jun 2023It remains challenging to construct multifunctional chiral stimulus-responsive molecules and to modulate their morphology at the nanoscale. In this paper, we synthesized...
It remains challenging to construct multifunctional chiral stimulus-responsive molecules and to modulate their morphology at the nanoscale. In this paper, we synthesized a novel chiral molecule with both photoactive and potentially bioactive properties and found that the morphological changes of its self-assembly were influenced by solvent polarity and light exposure. This work enabled the synthesized molecule to undergo - isomerization efficiently under light irradiation by introducing highly oriented hydrogen bonds into the cyanostilbene part. The photoisomerization of the cyanostilbene part from - to -type was further exploited, leading to morphological changes from nanohelices to vesicles with chiroptical evolution. The light-modulated supramolecular chirality and nanostructure provide a green and efficient method for the design of responsive chiral materials.
PubMed: 37191115
DOI: 10.1039/d3nr01056b -
Archives of Physiology and Biochemistry Apr 2002Pituitary somatotropes and melanotropes have enabled us to investigate the molecular basis and functional dynamics underlying secretory plasticity, an ability of... (Review)
Review
Pituitary somatotropes and melanotropes have enabled us to investigate the molecular basis and functional dynamics underlying secretory plasticity, an ability of endocrine cells to adapt their activity to the changing physiologic requirements, which generates discrete cell subpopulations within each cell hormonal type. Porcine somatotropes comprise two morphologically distinct subpopulations of low- (LD) and high-density (HD) cells, separable by Percoll gradient, that respond differently to hypothalamic regulators. In LD somatotropes, somatostatin (SRIF) inhibits growth hormone (GH)-releasing hormone (GHRH)-induced GH secretion. Conversely, SRIF alone stimulates GH release from HD somatotropes. These disparate SRIF actions entail a molecular signaling heterogeneity, in that SRIF increases cAMP levels in HD but not in LD cells as a requisite to stimulate GH release. GHRH-stimulated GH release also involves differential signaling in LD and HD cells: although it acts primarily through the cAMP/extracellular Ca2+ route in both somatotrope subsets, full response of LD somatotropes also requires the inositol phosphate/intracellular Ca2+ pathway. Amphibian melanotropes, which regulate skin adaptation to background color by secreting POMC-derived alpha-melanocyte-stimulating hormone (alphaMSH), also comprise two subpopulations with divergent secretory phenotypes. LD melanotropes show high biosynthetic and secretory activities and high responsiveness to multiple hypothalamic factors. Conversely, HD melanotropes constitute a hormone-storage subset poorly responsive to regulatory inputs. Interestingly, in black-adapted animals most melanotropes acquire the highly-secretory LD phenotype, whereas white-background adaptation, which requires less alphaMSH, converts melanotropes to the storage HD phenotype. These same interconversions can be reproduced in vitro using appropriate hypothalamic factors, thus revealing the pivotal role of the hypothalamus in regulating the functional dynamics of the secretory plasticity. Furthermore, this regulation likely involves a precise control of the secretory pathway, as suggested by the differential distribution in LD and HD melanotropes of key components of the intracellular transport, processing, and storage of secretory proteins. Hence, molecular signaling heterogeneity and unique secretory pathway components seem to relevantly contribute to the control of secretory plasticity, thereby enabling endocrine cells to finely adjust their dynamic response to the specific hormonal requirements.
Topics: Animals; Growth Hormone; Growth Hormone-Releasing Hormone; Pituitary Gland; Pituitary Hormones; Ranidae; Somatostatin; Swine; alpha-MSH
PubMed: 11935407
DOI: 10.1076/apab.110.1.106.907 -
Anticancer Research Jul 2009[18F]-fluorodeoxyglucose with positron-emission tomography (PET) and computed tomography (CT) scans were used to assess morphological and metabolic tumour response after...
BACKGROUND
[18F]-fluorodeoxyglucose with positron-emission tomography (PET) and computed tomography (CT) scans were used to assess morphological and metabolic tumour response after chemotherapy in metastatic colorectal cancer.
PATIENTS AND METHODS
Twenty-five patients were evaluated after 4 courses of chemotherapy (+/-target therapy), and among them 20 patients after 2 courses. Response Evaluation Criteria In Solid Tumors (RECIST) and European Organisazion for Research and Treatment of Cancer (EORTC) criteria were used to evaluate CT and PET respectively.
RESULTS
Discrepancies between the two procedures were noted after 4 courses of chemotherapy in patient-based analysis. Two morphologically complete responses (CR) were correlated with metabolic response. Seven morphological partial responses (PR) were evaluated as 3 metabolic PR, 2 CR and 1 progressive disease (PD). Seventeen cases of morphologically stable disease (SD) were evaluated as 3 metabolic CR, 13 PR and 1 PD. These discrepancies were confirmed in lesion-based analysis. Perfect concordance was noted between metabolic responses obtained after 2 and 4 cycles.
CONCLUSION
Morphological and metabolic imaging does not permit concordant therapeutic assessment in metastatic colorectal cancer.
Topics: Adult; Aged; Antineoplastic Agents; Colorectal Neoplasms; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Neoplasm Metastasis; Positron-Emission Tomography; Tomography, X-Ray Computed
PubMed: 19596929
DOI: No ID Found -
Bioorganic & Medicinal Chemistry Mar 2022The construction of multistimuli-responsive nanoaggregate has become one of the increasingly significant research topics in supramolecular chemistry. We herein reported...
The construction of multistimuli-responsive nanoaggregate has become one of the increasingly significant research topics in supramolecular chemistry. We herein reported the pH- and glutathione dual-responsive supramolecular assemblies fabricated by the disulfide-containing pillar[4]arene and tetraphenylethylene derivatives possessing different alkyl chains in length. Morphological characterization experiments showed the binary supramolecular assemblies formed well-defined nanoparticles, which could facilitate their endocytosis in cells. More remarkably, due to the compact nanostructures and the existence of acidifiable carboxyl group and bioreducible disulfide linkage in pillar[4]arene, the obtained nanoaggregates presented high drug-loading efficiency and sustained drug release behaviors, as well as the targeted fluorescence imaging ability in cancer cells. Thus, it can be envisioned that such microenvironment-adaptable supramolecular nanoassemblies featuring dual stimuli-responsiveness and fluorescence-imaging abilities may be developed as more appealing nanosystems for the therapy of refractory disease.
Topics: Antibiotics, Antineoplastic; Calixarenes; Cell Line; Cell Proliferation; Disulfides; Dose-Response Relationship, Drug; Doxorubicin; Drug Liberation; Drug Screening Assays, Antitumor; Humans; Molecular Structure; Optical Imaging; Structure-Activity Relationship
PubMed: 35131545
DOI: 10.1016/j.bmc.2022.116649 -
Frontiers in Physiology 2023Advanced analysis of the morphological features of the photoplethysmographic (PPG) waveform may provide greater understanding of mechanisms of action of...
Advanced analysis of the morphological features of the photoplethysmographic (PPG) waveform may provide greater understanding of mechanisms of action of photobiomodulation (PBM). Photobiomodulation is a non-ionizing, red to near-infrared irradiation shown to induce peripheral vasodilatation, promote wound healing, and reduce pain. Using laser Doppler flowmetry combined with thermal imaging we found previously in a clinical study that PBM stimulates microcirculatory blood flow and that baseline palm skin temperature determines, at least in part, why some individuals respond favorably to PBM while others do not. "Responders" (n = 12) had a skin temperature range of 33°C-37.5°C, while "non-responders" (n = 8) had "cold" or "hot" skin temperature (<33°C or >37.5°C respectively). The continuous PPG signals recorded from the index fingers of both hands in the original clinical study were subjected to advanced post-acquisitional analysis in the current study, aiming to identify morphological features that may improve the accuracy of discrimination between potential responders and non-responders to PBM. The PPG signals were detrended by subtracting the lower envelope from the raw signal. The Root Mean Square (RMS) and Entropy features were extracted as were two additional morphological features -- Smoothness and number of local extrema per PPG beat (#Extrema). These describe the signal jaggedness and were developed specifically for this study. The Wilcoxon test was used for paired comparisons. Correlations were determined by the Spearman correlation test (r). The PPG waveforms of responders to PBM had increased amplitude and decreased jaggedness (Baseline vs. 10' post-irradiation: Entropy, 5.0 ± 1.3 vs. 3.9 ± 1.1, = 0.012; #Extrema, 4.0 ± 1.1 vs. 3.0 ± 1.6, = 0.009; RMS, 1.6 ± 0.9 vs. 2.3 ± 1.2, = 0.004; Smoothness, 0.10 ± 0.05 vs. 0.19 ± 0.16, = 0.016). In addition, unilateral irradiation resulted in a bilateral response, although the response of the contralateral, non-irradiated hand was shorter in duration and lower in magnitude. Although subjects with 'cold,' or 'hot,' baseline skin temperature appeared to have morphologically distinct PPG waveforms, representing vasoconstriction and vasodilatation, these were not affected by PBM irradiation. This pilot study indicates that post-acquisitional analysis of morphological features of the PPG waveform provides new measures for the exploration of microcirculation responsiveness to PBM.
PubMed: 37817983
DOI: 10.3389/fphys.2023.1175470