36,914 results match your criteria pi45p maintains

Recovery of Unicellular Cyanobacteria from Nitrogen Chlorosis: A Model for Resuscitation of Dormant Bacteria.

Microb Physiol 2021 Apr 20:1-10. Epub 2021 Apr 20.

Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Eberhard Karls University Tübingen, Tübingen, Germany.

Nitrogen starvation induces developmental transitions in cyanobacteria. Whereas complex multicellular cyanobacteria of the order Nostocales can differentiate specialized cells that perform nitrogen fixation in the presence of oxygenic photosynthesis, non-diazotrophic unicellular strains, such as Synechococcus elongatus or Synechocystis PCC 6803, undergo a transition into a dormant non-growing state. Due to loss of pigments during this acclimation, the process is termed chlorosis. Read More

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Adaptive cell invasion maintains lateral line organ homeostasis in response to environmental changes.

Dev Cell 2021 Apr 13. Epub 2021 Apr 13.

Stowers Institute for Medical Research, Kansas City, MO 64110, USA. Electronic address:

Mammalian inner ear and fish lateral line sensory hair cells (HCs) detect fluid motion to transduce environmental signals. Actively maintained ionic homeostasis of the mammalian inner ear endolymph is essential for HC function. In contrast, fish lateral line HCs are exposed to the fluctuating ionic composition of the aqueous environment. Read More

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Selection maintains protein interactome resilience in the long-term evolution experiment with Escherichia coli.

Genome Biol Evol 2021 Apr 20. Epub 2021 Apr 20.

Department of Biomedical Engineering, Duke University, Durham, NC, USA.

Most cellular functions are carried out by a dynamic network of interacting proteins. An open question is whether the network properties of protein interactomes represent phenotypes under natural selection. One proposal is that protein interactomes have evolved to be resilient, such that they tend to maintain connectivity when proteins are removed from the network. Read More

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Binder-Free Electrospun Ni-Mn-O Nanofibers Embedded in Carbon Shells with Ultrahigh Energy and Power Densities for Highly Stable Next-Generation Energy Storage Devices.

Langmuir 2021 Apr 20. Epub 2021 Apr 20.

Energy Materials Laboratory, School of Sciences and Engineering, The American University in Cairo, New Cairo 11835, Egypt.

We demonstrate the fabrication of binder-free electrospun nickel-manganese oxides embedded into carbon-shell fibrous electrodes. The morphological and structural properties of the assembled electrode materials were elucidated by high-resolution transmission electron microscopy (HR-TEM), field-emission scanning electron microscopy, and glancing-angle X-ray diffraction. The fibrous structure of the electrodes was retained even after annealing at high temperatures. Read More

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Robust Gold Nanocluster Protected with Amidinates for Electrocatalytic CO2 Reduction.

Angew Chem Int Ed Engl 2021 Apr 19. Epub 2021 Apr 19.

Tsinghua University, Chemistry Department, 1 Tsinghua Yuan, Haidian District, 100084, Beijing, CHINA.

The first all-amidinate-protected gold nanocluster [Au28(Ph-form)12](OTf)2 (Ph-form = N,N'-Diphenylformamidine) ( Au28 ) has been synthesized and structurally resolved. Single crystal X-ray diffraction reveals that Au28 has a compact Au4@Au24 tetrahedral core-shell structure of T symmetry, which is fully protected by 12 bridging formamidinate ligands. This cluster is quite robust as indicated by the fact that it can stay intact in solution at 80 °C for 6 d. Read More

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Modulation the acidic and basic site concentration of the metal-organic framework derivatives to promote the carbon dioxide epoxidation reaction.

Chemistry 2021 Apr 19. Epub 2021 Apr 19.

Hunan University, College of Chemistry and Chemical Engineering, CHINA.

Metal-organic Framework (MOF) is an ideal precursor/template for porous carbon, and its active components are uniformly doped, which can be used in energy storage and catalytic conversion fields. Metal-organic framework PCN-224 with carboxylporphyrin as ligand was synthesized, and then Zn 2+ and Co 2+ ions were coordinated in the center of the porphyrin ring by post-modification. Here, PCN-224-ZnCo with different ratios of bimetallic Zn 2+ /Co 2+ ions is used as the precursor, and the metal-nitrogen-carbon(M-N-C) material of PCN-224-ZnCo-950 was obtained by pyrolysis the precursor at 950°C in Ar. Read More

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GPR182 is an endothelium-specific atypical chemokine receptor that maintains hematopoietic stem cell homeostasis.

Proc Natl Acad Sci U S A 2021 Apr;118(17)

Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, 61231, Germany;

G protein-coupled receptor 182 (GPR182) has been shown to be expressed in endothelial cells; however, its ligand and physiological role has remained elusive. We found GPR182 to be expressed in microvascular and lymphatic endothelial cells of most organs and to bind with nanomolar affinity the chemokines CXCL10, CXCL12, and CXCL13. In contrast to conventional chemokine receptors, binding of chemokines to GPR182 did not induce typical downstream signaling processes, including G- and G-mediated signaling or β-arrestin recruitment. Read More

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Cell differentiation and the cytoskeleton in Acetabularia.

Diedrik Menzel

New Phytol 1994 Nov;128(3):369-393

Max-Planck-Institut für Zellbiologie, Rosenhof, 68526 Ladenburg, Germany.

In multicellular organisms, differentiation of individual cells is typically linked to the development of the whole organism. As cells acquire tissue-specific morphologies and become functionally specialized they lose in turn a number of other functions. A free living, single celled organism, however, maintains all such functions. Read More

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November 1994

The epidermal surface of the maize root tip: II. Abnormalities in a mutant which grows crookedly through soil.

New Phytol 1993 Dec;125(4):801-811

Department of Biology, Carleton University, Ottawa, Canada K1S 5B6.

The mutation Ageotropic (Agt) results in defective development of the surface pellicle which overlies the young epidermal cells of mesocotyl and nodal roots of maize. In roots of plants of the parent, cv. Kys, pellicle development is normal. Read More

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December 1993

Tansley Review No. 45 Wall growth, protein excretion and morphogenesis in fungi.

New Phytol 1993 Mar;123(3):397-413

Department of Plant Biology, University of Groningen, Kerklaan 30, 9751 NN Haren, The Netherlands.

With the exception of the unicellular yeasts, fungi typically grow by means of hyphae that extend only at their apices and ramify into a mycelium. This mode of growth provides fungi with a certain mobility and the ability to invade dead and living organic substrata. They are thus the main decomposers of plant residues but they also have established intricate symbiotic relationships with plants, both mutualistic and parasitic. Read More

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Changes in macromolecular allocation in nondividing algal symbionts allow for photosynthetic acclimation in the lichen Lobaria pulmonaria.

New Phytol 2003 Sep;159(3):709-718

Department of Biology and Coastal Wetlands Institute, Mount Allison University, Sackville, New Brunswick, E4L 1G7, Canada.

•   The lichen Lobaria pulmonaria survives large seasonal environmental changes through physiological acclimation to ambient conditions. •   We quantitated algal cell population, cell division and key macromolecular levels associated with photosynthesis and nitrogen metabolism in L. pulmonaria sampled from four seasons with contrasting environmental conditions in a deciduous forest. Read More

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September 2003

Investigation of in vitro odonto/osteogenic capacity of cannabidiol on human dental pulp cell.

J Dent 2021 Apr 16:103673. Epub 2021 Apr 16.

Graduate Periodontics, School of Dentistry, University of Detroit Mercy, Detroit, MI, 48208, USA. Electronic address:

Introduction: Vital pulp treatment (VPT) maintains tooth vitality with certain dental materials by protecting pulp from noxious stimulation and promoting repair through enhancing cell proliferation/differentiation, migration, and inducing odontogenesis. As a non-psychotropic cannabis constituent, cannabidiol (CBD) process the properties of analgesic, anti-inflammation, and osteogenesis. Therefore, we hypothesize that CBD may induce the odonto/osteogenesis of human dental pulp cells (HDPCs), a critical feature using as effective pulp capping agent for VPT. Read More

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Halogen-Bonded Organic Framework (XOF) Based on Iodonium-Bridged N···I+···N Interactions: A Type of Diphase Periodic Organic Network.

Angew Chem Int Ed Engl 2021 Apr 19. Epub 2021 Apr 19.

Wuhan University, The Institute of Advanced Studies, 299 Bayi Road, 430072, Wuhan, CHINA.

Due to the fascinating structures and wide applications, porous materials with open frameworks have attracted more and more attentions. Herein, a novel two-dimensional (2D) halogen-bonded organic framework ( XOF-TPPE ) was successfully designed and fabricated by iodonium-bridged N···I + ···N interactions between pyridyl groups and I + for the first time. The formation of XOF-TPPE and its linear analogue was monitored by 1 H NMR, UV-Vis, X-ray photoelectron spectroscopy (XPS), IR, SEM, TEM, HRTEM and selected-area electron diffraction (SAED). Read More

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Studying models of balancing selection using phase-type theory.

Genetics 2021 Apr 19. Epub 2021 Apr 19.

Department of Mathematics, Aarhus University, DK-8000 Aarhus C, Denmark.

Balancing selection (BLS) is the evolutionary force that maintains high levels of genetic variability in many important genes. To further our understanding of its evolutionary significance, we analyse models with BLS acting on a biallelic locus: an equilibrium model with long-term BLS, a model with long-term BLS and recent changes in population size, and a model of recent BLS. Using phase-type theory, a mathematical tool for analysing continuous time Markov chains with an absorbing state, we examine how BLS affects polymorphism patterns in linked neutral regions, as summarised by nucleotide diversity, the expected number of segregating sites, the site frequency spectrum, and the level of linkage disequilibrium (LD). Read More

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Neutral Cyclometalated Ir(III) Complexes with Pyridylpyrrole Ligand for Photocatalytic Hydrogen Generation from Water.

Inorg Chem 2021 Apr 19. Epub 2021 Apr 19.

College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Chemical Power Sources, Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources, Central South University, Changsha, Hunan 410083, People's Republic of China.

To explore structure-activity relationships with respect to light-harvesting behavior, a family of neutral iridium complexes [Ir(ppy)(L)] - (where ppy = 2-phenylpyridine, and N̂N = 2-(1-pyrrol-2-yl)pyridine and its functionalized derivatives) were designed and synthesized. The structural modifications in metal complexes are accomplished through the attributions of electron-donating CH in , OCH in , and electron-withdrawing CF in . The structural analysis displays that the pyridylpyrrole acts as one-negative charged bidentated ligand to chelate the iridium center. Read More

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Mitochondrial protein import as a quality control sensor.

Biol Cell 2021 Apr 18. Epub 2021 Apr 18.

Biophysics & Structural Genomics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata, 700064, India.

Mitochondria are organelles involved in various functions related to cellular metabolism and homeostasis. Though mitochondria contain own genome, their nuclear counterparts encode most of the different mitochondrial proteins. These are synthesized as precursors in the cytosol and have to be delivered into the mitochondria. Read More

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ATG9A regulates proteostasis through reticulophagy receptors FAM134B and SEC62 and folding chaperones CALR and HSPB1.

iScience 2021 Apr 16;24(4):102315. Epub 2021 Mar 16.

Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA.

The acetylation of ATG9A within the endoplasmic reticulum (ER) lumen regulates the induction of reticulophagy. ER acetylation is ensured by AT-1/SLC33A1, a membrane transporter that maintains the cytosol-to-ER flux of acetyl-CoA. Defective AT-1 activity, as caused by heterozygous/homozygous mutations and gene duplication events, results in severe disease phenotypes. Read More

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BCG Moreau N-Terminal Loss Leads to a Less Stable Dodecin With Lower Flavin Binding Capacity.

Front Cell Infect Microbiol 2021 31;11:658888. Epub 2021 Mar 31.

Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil.

Tuberculosis still remains a concerning health problem worldwide. Its etiologic agent, , continues to be the focus of research to unravel new prophylactic and therapeutic strategies against this disease. The only vaccine in use against tuberculosis is based on the attenuated strain, BCG. Read More

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Minimizing VPD Fluctuations Maintains Higher Stomatal Conductance and Photosynthesis, Resulting in Improvement of Plant Growth in Lettuce.

Front Plant Sci 2021 1;12:646144. Epub 2021 Apr 1.

Institute for Sustainable Agro-Ecosystem Services, The University of Tokyo, Nishitokyo, Japan.

Vapor pressure deficit (VPD) is considered to be one of the major environmental factors influencing stomatal functions and photosynthesis, as well as plant growth in crop and horticultural plants. In the greenhouse cultivation, air temperature and relative air humidity are regulated by switching on/off the evaporative systems and opening/closing the roof windows, which causes VPD fluctuation. However, it remains unclear how VPD fluctuation affects photosynthetic and growth performance in plants. Read More

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Clinical interventions aimed at expanding access to dermatologic care.

Dermatol Online J 2021 Mar 15;27(3). Epub 2021 Mar 15.

Florida State University College of Medicine, Tallahassee, FL.

In the United States access to healthcare continues to be a major issue. Although "top down" public policy approaches hold promise for expanding access, a lack of political consensus has hindered progress. A review of the literature was conducted to investigate the efficacy of clinical interventions aimed at expanding access to care from the "bottom up. Read More

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Evaluation of the Subscapularis Split Created with Passive Rotation During Arthroscopic Dynamic Anterior Stabilization (DAS): a Cadaveric Study.

Orthop Traumatol Surg Res 2021 Apr 15:102934. Epub 2021 Apr 15.

Division of Orthopaedics and Trauma Surgery, La Tour Hospital, Faculty of Medicine, University of Geneva - Division of Orthopaedics and Trauma Surgery, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland. Electronic address:

Introduction: The purpose of the present study was to analyze the ability to create a subscapularis split by passive rotation of the arm during dynamic anterior stabilization (DAS) and to analyze the new geometry of the the long head of the biceps LHB.

Hypothesis: The hypothesis was that this passive simple technique can create subscapularis split without additional dissection giving rise to new position of LHB with a new stabilization function.

Material And Methods: A technique of subscapularis split using the LHB was used in 12 fresh-frozen human cadaveric shoulders. Read More

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Can electronic prescribing mandates reduce opioid-related overdoses?

Econ Hum Biol 2021 Apr 9;42:101000. Epub 2021 Apr 9.

RAND, United States. Electronic address:

As the opioid crisis has escalated, states have enacted numerous policies targeting opioid access and monitoring possible misuse. Recently, the majority of states have passed electronic prescribing mandates for controlled substances. These mandates require that controlled substances be prescribed electronically directly to the pharmacy. Read More

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Melatonin rescues cerebral ischemic events through upregulated tunneling nanotube-mediated mitochondrial transfer and downregulated mitochondrial oxidative stress in rat brain.

Biomed Pharmacother 2021 Apr 14;139:111593. Epub 2021 Apr 14.

School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; Stem Cell Research Center, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan; Graduate Institute of Basic Medicine, Fu Jen Catholic University, Taipei, Taiwan; Department of Life Science, Tunghai University, Taichung, Taiwan. Electronic address:

Background: Cerebral ischemic events, comprising of excitotoxicity, reactive oxygen production, and inflammation, adversely impact the metabolic-redox circuit in highly active neuronal metabolic profile which maintains energy-dependent brain activities. Therefore, we investigated neuro-regenerative potential of melatonin (Mel), a natural biomaterial secreted by pineal gland.

Methods: We specifically determined whether Mel could influence tunneling nanotubes (TNTs)-mediated transfer of functional mitochondria (Mito) which in turn may alter membrane potential, oxidative stress and apoptotic factors. Read More

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Facile carboxylation of natural eggshell membrane for highly selective uranium (VI) adsorption from radioactive wastewater.

Environ Sci Pollut Res Int 2021 Apr 16. Epub 2021 Apr 16.

State Key Laboratory of Environment-friendly Energy Materials, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, People's Republic of China.

With the commercial nuclear technology rising in society nowadays, it is of paramount importance to remove uranium (VI) in radioactive wastewater through a cost-effective and efficient way. Due to simple operation, low cost and abundant adsorbents, the adsorption method has been widely used to treat the radioactive wastewater. However, unsatisfactory selectivity and potential secondary pollution of most adsorbents hamper their practical large-scale application. Read More

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Quantum chaos and the correspondence principle.

Phys Rev E 2021 Mar;103(3):L030201

Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China.

The correspondence principle is a cornerstone in the entire construction of quantum mechanics. This principle has been recently challenged by the observation of an early-time exponential increase of the out-of-time-ordered correlator (OTOC) in classically nonchaotic systems [E. B. Read More

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A novel framework of Bayesian optimal interval design for phase I trials with late-onset toxicities.

Contemp Clin Trials 2021 Apr 13:106404. Epub 2021 Apr 13.

Biostatistics and Research Decision Sciences, Merck & Co., Inc., Kenilworth, NJ 07033, USA. Electronic address:

As molecularly targeted agents (MTAs) and immunotherapies have widely demonstrated delayed toxicity profile after multiple treatment cycles, the traditional phase I dose-finding designs may not be appropriate anymore because they just account for the acute toxicities occurring in the early period of treatment. When the dose-limiting toxicity (DLT) assessment window is prolonged to account for late-onset DLTs, it will cause logistic issues if the enrollment is suspended until all the DLT information is collected. We propose a novel framework to estimate the toxicity probability in the scenarios where some patients' DLT information are not complete and then implement the Bayesian optimal interval (BOIN) design to make decisions on dose escalation/de-escalation. Read More

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The European Bioinformatics Community for Mass Spectrometry (EuBIC-MS): an open community for bioinformatics training and research.

Rapid Commun Mass Spectrom 2021 Apr 16:e9087. Epub 2021 Apr 16.

European Bioinformatics Community for Mass Spectrometry, Belgium.

The European Bioinformatics Community for Mass Spectrometry (EuBIC-MS; eubic-ms.org) was founded in 2014 to unite European computational mass spectrometry researchers and proteomics bioinformaticians working in academia and industry. EuBIC-MS maintains educational resources (proteomics-academy. Read More

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Persistent expression of interleukin-17 and downstream effector cytokines in recalcitrant psoriatic lesions after ustekinumab treatment.

J Dermatol 2021 Apr 15. Epub 2021 Apr 15.

Department of Dermatology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Korea.

The interleukin (IL)-23/T-helper (Th)17 axis is considered central to the pathogenesis of psoriasis, with IL-36γ considered a marker for histological differential diagnosis. However, expression data regarding key cytokines in the pathogenesis of psoriasis, as well as data on the effects of IL-23 inhibition on downstream cytokines in human psoriatic skin, are limited. We investigated the expression profile of key cytokines and the effect of ustekinumab (UST) on cytokine expression in human psoriatic tissue. Read More

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Solid-state culture of Azospirillum brasilense: a reliable technology for biofertilizer production from laboratory to pilot scale.

Bioprocess Biosyst Eng 2021 Apr 15. Epub 2021 Apr 15.

Department of Biotechnology, Iztapalapa Campus, Metropolitan Autonomous University, 09340, Mexico City, Mexico.

A biofertilizer of Azospirillum brasilense was produced in solid-state culture (SSC) from laboratory to pilot scale. Similar operation conditions (continuous aeration and mild intermittent mixing) and two dimensionless numbers with similar L/D ratio and a similar working volume were applied to reach a scale-up factor of 75. An innovative bioreactor with rotating helical ribbons (15 kg wet matter) was used at pilot scale. Read More

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