What is the role of sporadic phloem sap nitrate?

Why is phloem sap nitrate kept low?

10.22541/au.161607706.62504876/v1 ◽

2021 ◽

Author(s):

Jing Cui ◽

Andreas D. Peuke ◽

Anis Limami ◽

Guillaume Tcherkez

Keyword(s):

Nutrient Cycling ◽

Physical Properties ◽

Plant Development ◽

Nutrient Transport ◽

Substantial Evidence ◽

Phloem Sap ◽

Essential Component

Since the first description of phloem sap composition nearly 60 years ago, it is generally assumed that phloem sap does not contain nitrate and that there is little or no backflow of nitrate from shoots to roots. While it is true that nitrate can occasionally be absent from phloem sap, there is now substantial evidence that phloem can carry nitrate and furthermore, transporters involved in nitrate redistribution to shoot sink organs and roots have been found. This raises the question of why nitrate may or may not be present in phloem sap, why its concentration is generally kept low, and whether plant shoot-root nutrient cycling also involves nitrate. We propose here that phloem sap nitrate is not only an essential component of plant nutritional signaling but also contributes to physical properties of phloem sap and as such, its concentration is controlled to ensure proper coordination of plant development and nutrient transport.

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Histomorphological Assessment of Formalin versus Nonformalin Fixatives in Diagnostic Surgical Pathology

Journal of Laboratory Physicians ◽

10.1055/s-0040-1722546 ◽

2020 ◽

Vol 12 (04) ◽

pp. 271-275

Author(s):

Jayaprakash Kubalady Shetty ◽

Hannah Fathima Babu ◽

Kishan Prasad Hosapatna Laxminarayana

Keyword(s):

Methyl Alcohol ◽

Potential Role ◽

Tissue Architecture ◽

Substantial Evidence ◽

Diagnostic Pathology ◽

Rapid Fixation ◽

Chromatin Texture ◽

Upper Respiratory ◽

Potential Human Health

Abstract Introduction Fixation is the critical step in the preservation of tissues in diagnostic pathology. The formalin is an economical and excellent fixative with the inherent property of adequate fixation. The well-established side effects of formalin include mucosal irritation, upper respiratory diseases, and corrosive injury to the gastrointestinal tract. In addition, substantial evidence exists regarding the potential role of formaldehyde as a human carcinogen. The carcinogenic and toxic effects of formalin encourage searching for alternative fixatives for tissue fixation. However, “the formalin dogma” has severely hampered the search for alternative fixatives for many years. Material and Methods Ninety tissues of liver and skeletal muscle obtained during autopsies were immersed in adequate amounts of the following fixatives: formalin (10%), methyl alcohol (70%), and acetone (100%). The comparison among the three was made based on time for fixation, preservation of tissue architecture, cell borders, cytoplasm, nuclear contours, chromatin texture, and uniformity of staining. Results The tissue preserved in formalin undergoes rapid fixation compared with alcohol and acetone. The tissue architecture, cell border characteristics of alcohol and acetone was found satisfactory compared with formalin. The cytoplasm and nuclear contour were superior with the formalin. The chromatin texture and uniformity of staining were similar with all the three fixatives. Conclusion The formalin is considered superior to most of the parameters, whereas both methyl alcohol and acetone showed nearly equivalent scores. Hence, owing to the potential human health hazards and carcinogenicity of formalin, no rational reasons hamper the complete substitution of formalin with alternative fixatives such as alcohol and acetone in diagnostic pathology and medical research.

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The role of rheological premonitory of hydrogels based on cellulose nanofibers and polymethylsilsesquioxane on the physical properties of corresponding aerogels

Polymer Engineering & Science ◽

10.1002/pen.25671 ◽

2021 ◽

Vol 61 (4) ◽

pp. 1220-1231

Author(s):

Pragya Gupta ◽

Akanksha Pandey ◽

Kirtiraj K. Gaikwad ◽

Sunanda Roy ◽

Pradip K. Maji

Keyword(s):

Physical Properties ◽

Cellulose Nanofibers

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Role of FTFSI anion asymmetry on physical properties of AFTFSI (A = Li, Na and K) based electrolytes. Consequences on supercapacitor application.

ChemPhysChem ◽

10.1002/cphc.202100439 ◽

2021 ◽

Author(s):

Joseph Chidiac ◽

Laure Timperman ◽

meriem anouti

Keyword(s):

Physical Properties ◽

Supercapacitor Application

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Astrocytes and neuroinflammation in Alzheimer's disease

Biochemical Society Transactions ◽

10.1042/bst20140155 ◽

2014 ◽

Vol 42 (5) ◽

pp. 1321-1325 ◽

Cited By ~ 47

Author(s):

Emma C. Phillips ◽

Cara L. Croft ◽

Ksenia Kurbatskaya ◽

Michael J. O’Neill ◽

Michael L. Hutton ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Inflammatory Responses ◽

Amyloid Β ◽

Synaptic Dysfunction ◽

Amyloid Β Peptide ◽

Substantial Evidence ◽

Models Of Disease ◽

Opposing Effects

Increased production of amyloid β-peptide (Aβ) and altered processing of tau in Alzheimer's disease (AD) are associated with synaptic dysfunction, neuronal death and cognitive and behavioural deficits. Neuroinflammation is also a prominent feature of AD brain and considerable evidence indicates that inflammatory events play a significant role in modulating the progression of AD. The role of microglia in AD inflammation has long been acknowledged. Substantial evidence now demonstrates that astrocyte-mediated inflammatory responses also influence pathology development, synapse health and neurodegeneration in AD. Several anti-inflammatory therapies targeting astrocytes show significant benefit in models of disease, particularly with respect to tau-associated neurodegeneration. However, the effectiveness of these approaches is complex, since modulating inflammatory pathways often has opposing effects on the development of tau and amyloid pathology, and is dependent on the precise phenotype and activities of astrocytes in different cellular environments. An increased understanding of interactions between astrocytes and neurons under different conditions is required for the development of safe and effective astrocyte-based therapies for AD and related neurodegenerative diseases.

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