Isolation and characterisation of the homogalacturonan from type II cell walls of the commelinoid monocot wheat using HF-solvolysis

Different sources of inorganic nitrogen exert compositional changes on type II cell walls of the grass and crop model Brachypodium distachyon in an organ- and development-specific manner.

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Plasticidad estructural de la pared celular tipo II en cultivos celulares de maíz (Zea mays L.) habituados a diclobenil = Structural plasticity of type II cell walls in dichlobenil habituated maize (Zea mays L.) cell cultures

10.18002/10612/849 ◽

2010 ◽

Author(s):

Hugo Mélida Martínez

Keyword(s):

Zea Mays ◽

Cell Cultures ◽

Cell Walls ◽

Zea Mays L ◽

Structural Plasticity ◽

Type Ii ◽

L Cell ◽

Type Ii Cell

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A Rice Family 9 Glycoside Hydrolase Isozyme with Broad Substrate Specificity for Hemicelluloses in Type II Cell Walls

Plant and Cell Physiology ◽

10.1093/pcp/pcl020 ◽

2006 ◽

Vol 47 (11) ◽

pp. 1541-1554 ◽

Cited By ~ 19

Author(s):

Kouki Yoshida ◽

Kozo Komae

Keyword(s):

Substrate Specificity ◽

Cell Walls ◽

Glycoside Hydrolase ◽

Type Ii ◽

Broad Substrate Specificity ◽

Type Ii Cell

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Covid-19 Interstitial Pneumonia: Histological and Immunohistochemical Features on Cryobiopsies

Respiration ◽

10.1159/000514822 ◽

2021 ◽

pp. 369-379

Author(s):

Claudio Doglioni ◽

Claudia Ravaglia ◽

Marco Chilosi ◽

Giulio Rossi ◽

Alessandra Dubini ◽

...

Keyword(s):

Interstitial Pneumonia ◽

Diffuse Alveolar Damage ◽

Alveolar Type ◽

Type Ii ◽

Cell Hyperplasia ◽

Nuclear Expression ◽

Alveolar Type Ii Cell ◽

Hyaline Membranes ◽

Type Ii Cell ◽

Phosphorylated Stat3

Background: The pathogenetic steps leading to Covid-19 interstitial pneumonia remain to be clarified. Most postmortem studies to date reveal diffuse alveolar damage as the most relevant histologic pattern. Antemortem lung biopsy may however provide more precise data regarding the earlier stages of the disease, providing a basis for novel treatment approaches. Objectives: To ascertain the morphological and immunohistochemical features of lung samples obtained in patients with moderate Covid-19 pneumonia. Methods: Transbronchial lung cryobiopsy was carried out in 12 Covid-19 patients within 20 days of symptom onset. Results: Histopathologic changes included spots of patchy acute lung injury with alveolar type II cell hyperplasia, with no evidence of hyaline membranes. Strong nuclear expression of phosphorylated STAT3 was observed in >50% of AECII. Interalveolar capillaries showed enlarged lumen and were in part arranged in superposed rows. Pulmonary venules were characterized by luminal enlargement, thickened walls, and perivascular CD4+ T-cell infiltration. A strong nuclear expression of phosphorylated STAT3, associated with PD-L1 and IDO expression, was observed in endothelial cells of venules and interstitial capillaries. Alveolar spaces macrophages exhibited a peculiar phenotype (CD68, CD11c, CD14, CD205, CD206, CD123/IL3AR, and PD-L1). Conclusions: Morphologically distinct features were identified in early stages of Covid-19 pneumonia, with epithelial and endothelial cell abnormalities different from either classical interstitial lung diseases or diffuse alveolar damage. Alveolar type II cell hyperplasia was a prominent event in the majority of cases. Inflammatory cells expressed peculiar phenotypes. No evidence of hyaline membranes and endothelial changes characterized by IDO expression might in part explain the compliance and the characteristic pulmonary vasoplegia observed in less-advanced Covid-19 pneumonia.

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Regulation of extracellular matrix synthesis by TNF-α and TGF-β1 in type II cells exposed to coal dust

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1998.275.4.l637 ◽

1998 ◽

Vol 275 (4) ◽

pp. L637-L644 ◽

Cited By ~ 3

Author(s):

Yu-Chen Lee ◽

D. Eugene Rannels

Keyword(s):

Extracellular Matrix ◽

Cell Cultures ◽

Transforming Growth Factor ◽

Coal Dust ◽

Transforming Growth Factor Β1 ◽

Type Ii ◽

Tnf Α ◽

Type Ii Cell ◽

Primary Type ◽

Tgf Β1

Type II pulmonary epithelial cells respond to anthracite coal dust PSOC 867 with increased synthesis of extracellular matrix (ECM) components. Alveolar macrophages modulate this response by pathways that may involve soluble mediators, including tumor necrosis factor-α (TNF-α) or transforming growth factor-β1 (TGF-β1). The effects of TNF-α (10 ng/ml) and/or TGF-β1 (2 ng/ml) were thus investigated in dust-exposed primary type II cell cultures. In control day 1 or day 3 cultures, TNF-α and/or TGF-β1 had little or no effect on the synthesis of type II cellular proteins, independent of whether the cells were exposed to dust. With PSOC 867 exposure, where ECM protein synthesis is elevated, TNF-α and TGF-β1 further increased both the absolute and relative rates of ECM synthesis on day 3 but had little effect on day 1. Each mediator increased expression of fibronectin mRNA, as well as of ECM fibronectin content, in a manner qualitatively similar to their effects on synthesis. Thus TNF-α and TGF-β1 modulate both ECM synthesis and fibronectin content in coal dust-exposed type II cell cultures.

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P2u purinoceptor stimulation of surfactant secretion coupled to phosphatidylcholine hydrolysis in type II cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1994.267.5.l625 ◽

1994 ◽

Vol 267 (5) ◽

pp. L625-L633 ◽

Cited By ~ 11

Author(s):

L. I. Gobran ◽

Z. X. Xu ◽

Z. Lu ◽

S. A. Rooney

Keyword(s):

Phospholipase D ◽

Receptor Gene ◽

Primary Cultures ◽

Cell Receptor ◽

Northern Analysis ◽

Type Ii Cells ◽

Type Ii ◽

Type Ii Cell ◽

Subsequent Activation ◽

Phosphatidylcholine Secretion

ATP is known to stimulate surfactant phospholipid secretion in type II cells, and there is evidence that this effect is mediated by a P2 purinoceptor. At least five subtypes of the P2 receptor have been reported, but it is not clear which one exists on the type II cell. To determine whether it is the P2u subtype, at which UTP is equipotent with ATP, we have compared the effects of ATP and UTP on phosphatidylcholine secretion and second messenger formation in primary cultures of rat type II cells. ATP and UTP were equally potent in stimulating phosphatidylcholine secretion and phospholipase D activation. The potency order, UTP = ATP > ADP > 2-methylthio-ATP, was the same as that reported for the P2u receptor. UTP stimulated diacylglycerol and phosphatidic acid formation to the same extent as ATP. ATP also increased choline formation. Formation of diacylglycerol was biphasic, and the first peak in response to ATP was previously shown to be associated with inositol trisphosphate formation. Northern analysis showed that the P2u receptor gene was expressed to a greater extent in type II cells than in whole lung. These data suggest that ATP and UTP act via a P2u receptor that is coupled to phosphoinositide-specific phospholipase C with subsequent activation of phospholipase D acting on phosphatidylcholine. ATP has also been reported to act at an additional type II cell receptor coupled to adenylate cyclase. In contrast, UTP did not promote adenosine 3',5'-cyclic monophosphate formation and therefore does not act at that receptor.

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Connexin expression by alveolar epithelial cells is regulated by extracellular matrix

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.2001.280.2.l191 ◽

2001 ◽

Vol 280 (2) ◽

pp. L191-L202 ◽

Cited By ~ 32

Author(s):

Yihe Guo ◽

Cara Martinez-Williams ◽

Clare E. Yellowley ◽

Henry J. Donahue ◽

D. Eugene Rannels

Keyword(s):

Extracellular Matrix ◽

Epithelial Cells ◽

Gap Junction ◽

Intercellular Communication ◽

Translational Regulation ◽

Alveolar Epithelial Cells ◽

Alveolar Type ◽

Type Ii ◽

Gap Junction Intercellular Communication ◽

Type Ii Cell

Extracellular matrix (ECM) proteins promote attachment, spreading, and differentiation of cultured alveolar type II epithelial cells. The present studies address the hypothesis that the ECM also regulates expression and function of gap junction proteins, connexins, in this cell population. Expression of cellular fibronectin and connexin (Cx) 43 increase in parallel during early type II cell culture as Cx26 expression declines. Gap junction intercellular communication is established over the same interval. Cells plated on a preformed, type II cell-derived, fibronectin-rich ECM demonstrate accelerated formation of gap junction plaques and elevated gap junction intercellular communication. These effects are blocked by antibodies against fibronectin, which cause redistribution of Cx43 protein from the plasma membrane to the cytoplasm. Conversely, cells cultured on a laminin-rich ECM, Matrigel, express low levels of Cx43 but high levels of Cx26, reflecting both transcriptional and translational regulation. Cx26 and Cx43 thus demonstrate reciprocal regulation by ECM constituents.

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