Ultrastructure of cellular components of human trophoblasts during early pregnancy

1995 ◽  
Vol 7 (6) ◽  
pp. 1539 ◽  
Author(s):  
M Jaggi ◽  
PK Mehrotra ◽  
SC Maitra ◽  
SL Agarwal ◽  
K Das ◽  
...  
Keyword(s):  
Basement Membrane ◽  
Early Pregnancy ◽  
Central Area ◽  
Cell Types ◽  
Large Nucleus ◽  
Chorionic Villi ◽  
Intracellular Organization ◽  
Ultrathin Sections ◽  
Cellular Components ◽  
Prominent Nucleolus

Two cell types, the cyto- and syncytio-trophoblasts, were identified in human chorionic villi of 6-10 weeks' gestation. The intracellular organization of these cells was examined. Ultrathin sections of small pieces of chorionic villi revealed the presence of a multinucleate syncytiotrophoblastic layer, whose surface was covered with microvilli. The cytotrophoblasts, however, had a single large nucleus with a prominent nucleolus. An interesting feature of the basement membrane of these cells was the presence of aggregates of dark granules in samples of the earlier gestational age (6-8 weeks) and granular bodies having a dense outer ring and a translucent inner ring with a lucid central area in samples of 8-10 weeks' gestation. Both types of granules are mineralized and are assumed to perform a buffering role for maintaining the neutrality of the layer.

Progesterone decreased indoleamine 2,3-dioxygenase 1(IDO1) expression in early pregnancy chorionic villi and decidua

Autoimmunity ◽  
2021 ◽  
pp. 1-7
Author(s):  
Minyan Yang ◽  
Guanyou Huang ◽  
Hua Qian ◽  
Jun Wang ◽  
Shuyun Zhao ◽  
...  
Keyword(s):  
Early Pregnancy ◽  
Chorionic Villi ◽  
Indoleamine 2,3 Dioxygenase ◽  
Ido1 Expression

scholarly journals Location Matters: Navigating Regional Heterogeneity of the Neurovascular Unit

2021 ◽  
Vol 15 ◽  
Author(s):  
Louis-Philippe Bernier ◽  
Clément Brunner ◽  
Azzurra Cottarelli ◽  
Matilde Balbi
Keyword(s):  
Brain Function ◽  
Energy Demand ◽  
Neurovascular Unit ◽  
Cell Types ◽  
Brain Regions ◽  
Regional Heterogeneity ◽  
Regional Specialization ◽  
Multiple Cell ◽  
Cellular Components ◽  
The Brain

The neurovascular unit (NVU) of the brain is composed of multiple cell types that act synergistically to modify blood flow to locally match the energy demand of neural activity, as well as to maintain the integrity of the blood-brain barrier (BBB). It is becoming increasingly recognized that the functional specialization, as well as the cellular composition of the NVU varies spatially. This heterogeneity is encountered as variations in vascular and perivascular cells along the arteriole-capillary-venule axis, as well as through differences in NVU composition throughout anatomical regions of the brain. Given the wide variations in metabolic demands between brain regions, especially those of gray vs. white matter, the spatial heterogeneity of the NVU is critical to brain function. Here we review recent evidence demonstrating regional specialization of the NVU between brain regions, by focusing on the heterogeneity of its individual cellular components and briefly discussing novel approaches to investigate NVU diversity.

scholarly journals Extracellular Vesicles: An Emerging Mechanism Governing the Secretion and Biological Roles of Tenascin-C

2021 ◽  
Vol 12 ◽  
Author(s):  
Lucas Albacete-Albacete ◽  
Miguel Sánchez-Álvarez ◽  
Miguel Angel del Pozo
Keyword(s):  
Extracellular Vesicles ◽  
Molecular Mechanisms ◽  
Cell Communication ◽  
Cell Types ◽  
Target Cells ◽  
Tenascin C ◽  
Signalling Molecules ◽  
Inflammatory Processes ◽  
Bona Fide ◽  
Cellular Components

ECM composition and architecture are tightly regulated for tissue homeostasis. Different disorders have been associated to alterations in the levels of proteins such as collagens, fibronectin (FN) or tenascin-C (TnC). TnC emerges as a key regulator of multiple inflammatory processes, both during physiological tissue repair as well as pathological conditions ranging from tumor progression to cardiovascular disease. Importantly, our current understanding as to how TnC and other non-collagen ECM components are secreted has remained elusive. Extracellular vesicles (EVs) are small membrane-bound particles released to the extracellular space by most cell types, playing a key role in cell-cell communication. A broad range of cellular components can be transported by EVs (e.g. nucleic acids, lipids, signalling molecules and proteins). These cargoes can be transferred to target cells, potentially modulating their function. Recently, several extracellular matrix (ECM) proteins have been characterized as bona fide EV cargoes, exosomal secretion being particularly critical for TnC. EV-dependent ECM secretion might underpin diseases where ECM integrity is altered, establishing novel concepts in the field such as ECM nucleation over long distances, and highlighting novel opportunities for diagnostics and therapeutic intervention. Here, we review recent findings and standing questions on the molecular mechanisms governing EV–dependent ECM secretion and its potential relevance for disease, with a focus on TnC.

Ultrastructure of cellular components of human trophoblasts during early pregnancy

Placenta ◽  
1994 ◽  
Vol 15 (7) ◽  
pp. A34
Author(s):  
M. Jaggi ◽  
P.K. Mehrotra ◽  
S.C. Maitra ◽  
S.L. Agarwal ◽  
K. Das ◽  
...  
Keyword(s):  
Early Pregnancy ◽  
Cellular Components

scholarly journals The Role of Angiogenesis and Pro-Angiogenic Exosomes in Regenerative Dentistry

2019 ◽  
Vol 20 (2) ◽  
pp. 406 ◽  
Author(s):  
Alina-Andreea Zimta ◽  
Oana Baru ◽  
Mandra Badea ◽  
Smaranda Buduru ◽  
Ioana Berindan-Neagoe
Keyword(s):  
Stem Cells ◽  
Vascular Endothelial Cells ◽  
Cell Types ◽  
Toxic Waste ◽  
Vascular Endothelial ◽  
Regenerative Dentistry ◽  
Oral Tissue ◽  
Cellular Components ◽  
Stimulation Of

Dental surgeries can result in traumatic wounds that provoke major discomfort and have a high risk of infection. In recent years, density research has taken a keen interest in finding answers to this problem by looking at the latest results made in regenerative medicine and adapting them to the specificities of oral tissue. One of the undertaken directions is the study of angiogenesis as an integrative part of oral tissue regeneration. The stimulation of this process is intended to enhance the local availability of stem cells, oxygen levels, nutrient supply, and evacuation of toxic waste. For a successful stimulation of local angiogenesis, two major cellular components must be considered: the stem cells and the vascular endothelial cells. The exosomes are extracellular vesicles, which mediate the communication between two cell types. In regenerative dentistry, the analysis of exosome miRNA content taps into the extended communication between these cell types with the purpose of improving the regenerative potential of oral tissue. This review analyzes the stem cells available for the dentistry, the molecular cargo of their exosomes, and the possible implications these may have for a future therapeutic induction of angiogenesis in the oral wounds.

The relation between connective tissue cells and intercellular substances, including basement membranes

1975 ◽  
Vol 271 (912) ◽  
pp. 363-377 ◽  
Keyword(s):  
Endothelial Cells ◽  
Basement Membrane ◽  
Immune Complexes ◽  
Hydrolytic Enzymes ◽  
Inflammatory Cells ◽  
Cell Types ◽  
Cellular Level ◽  
Basement Membranes ◽  
The Body ◽  
Pathological Changes

Basement membranes are distributed widely in the body forming an extracellular matrix for epithelial and endothelial cells. The collagenous and glycoprotein constituents of basement membranes are synthesized by these two cell types. Disturbance of the interactions between basement membranes and their associated epithelial and endothelial cells can lead to the pathological changes seen in diseases involving basement membranes. These changes are illustrated here by reference to glomerulonephritis induced by the deposition of immune complexes in the glomerulus of the kidney, and chronic inflammatory changes occurring in the lung after inhalation of asbestos. In these diseases basement membrane changes can occur in several ways. Hydrolytic enzymes released from inflammatory cells degrade basement membranes while other factors released from these cells may stimulate synthesis of basement membrane constituents by epithelial and endothelial cells. Alternatively the physical separation of epithelial and endothelial cells from their basement membranes by space-occupying substances such as immune complexes can interfere with feedback mechanisms leading to synthesis of basement membrane constituents and cell proliferation. Studies of these pathological changes at a cellular level should shed new light on the ways in which cells interact with their pericellular environment.

203. A differential pattern of follistatin expression in the placenta between spontaneous, induced and non-labouring patient groups

2005 ◽  
Vol 17 (9) ◽  
pp. 77
Author(s):  
K. M. Rae ◽  
K. G. Hollebone ◽  
L. Meng ◽  
D. C. Clausen ◽  
J. R. McFarlane
Keyword(s):  
Vascular Endothelial Cells ◽  
Placental Tissue ◽  
Cell Types ◽  
Cross Sectional Study ◽  
Polyclonal Antiserum ◽  
Antigen Retrieval ◽  
Positive Staining ◽  
Cross Sectional ◽  
Chorionic Villi ◽  
Patient Groups

Follistatin has been identified in human placenta, fetal membranes and fluids, with serum follistatin concentrations rising during pregnancy, particularly near term. Our laboratory has shown follistatin concentrations rise across labour in spontaneous but not induced women.1 As the placenta is a source of follistatin, this study examined placental tissues using immunohistochemistry to determine differences in follistatin localization between groups. Placental tissue was collected immediately following delivery from three groups of women at term, spontaneous onset (n = 4), induction (n = 4) and non-labouring caesarian (n = 4), and immediately formalin fixed. Antigen-retrieval immunohistochemistry using a specific chicken polyclonal antiserum (CK20) raised against a follistatin peptide (AA 121-133) or pre-immune chicken serum was performed. Positive staining of syncytiotrophoblast cells of the chorionic villi was seen in patients undergoing spontaneous labour but not in the induced and caesarian delivery group. The two labouring groups (spontaneous and induced) both showed positive staining for the vascular endothelial cells within the chorionic villi and the stratum basale, whilst the caesarian delivery group was negative for any staining within these vessels. Positive staining of Hofbauer cells was observed in both labouring groups; however, the caesarian group showed infrequent positive staining of these cell types. The differences in expression pattern in the two labouring groups (spontaneous v. induced) may be due to variations in labour lengths (6.5 v. 4.5 h, respectively); however, we would have expected a lower level of expression in the same cell types rather than the complete absence of staining. The positive follistatin staining in the syncytiotrophoblast of spontaneous patients suggests this may be the source of the rising plasma follistatin seen in this group. These differences in staining support our hypothesis that an earlier endocrine signal is absent in the induced and caesarian patient groups. (1)Rae K, Hollebone K, Clausen DC, Chetty V, McFarlane JR. (2004). A Cross-Sectional Study of Follistatin During Labour in Women. The Endocrine Societies 86th Annual Meeting, New Orleans, 2004.

The MARCKS family of phospholipid binding proteins: regulation of phospholipase D and other cellular components

2004 ◽  
Vol 82 (1) ◽  
pp. 191-200 ◽  
Author(s):  
Meenakshi Sundaram ◽  
Harold W Cook ◽  
David M Byers
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Phospholipase D ◽  
Cell Types ◽  
Kinase Substrate ◽  
Kinase C ◽  
Acidic Phospholipids ◽  
Cellular Components ◽  
Specific Membrane ◽  
Recent Attention

Myristoylated alanine-rich C kinase substrate (MARCKS) and MARCKS-related protein (MRP) are essential proteins that are implicated in coordination of membrane-cytoskeletal signalling events, such as cell adhesion, migration, secretion, and phagocytosis in a variety of cell types. The most prominent structural feature of MARCKS and MRP is a central basic effector domain (ED) that binds F-actin, Ca2+-calmodulin, and acidic phospholipids; phosphorylation of key serine residues within the ED by protein kinase C (PKC) prevents the above interactions. While the precise roles of MARCKS and MRP have not been established, recent attention has focussed on the high affinity of the MARCKS ED for phosphatidylinositol 4,5-bisphosphate (PIP2), and a model has emerged in which calmodulin- or PKC-mediated regulation of these proteins at specific membrane sites could in turn control spatial availability of PIP2. The present review summarizes recent progress in this area and discusses how the above model might explain a role for MARCKS and MRP in activation of phospholipase D and other PIP2-dependent cellular processes.Key words: MARCKS, MRP, protein kinase C, PIP2, phospholipase D.

Sign in / Sign up

Export Citation Format

Share Document