Anatomy of Shuck Abscission in `Desirable' Pecan

Cellular changes associated with shuck dehiscence and markings deposited on pecan [Carya illinoinensis (Wangenh.) C. Koch] shells were examined by scanning electron and light microscopy. Fruit were sampled at three stages of maturity: 1) shuck and shell fused, 2) sutures separated (shuck opening), and 3) vascular system separated from shuck. Shuck dehiscence involved temporally regulated abscission events with shuck-shell, then shuck-suture, and finally shuck-vascular system separation. Abscission events occurred in a tissue zone common to and continuous among all three separation sites, even though segregated in time. Also, similar cell types and cellular changes were common to the three events. Thus, temporal segregation of abscission events was not due to differences in either tissue type or cellular modifications, but to maturation rate. Structures to become shell markings were single globules filling cells of the shuck inner tissue zone before shuck-shell separation. These globules were deposited on the shell at shuck-shell separation and were morphologically similar to deposits stuck to the dorsal shuck surface. Globules were partitioned differentially between the shuck and shell during shuck-shell separation. Thus, the inner zone of the shuck is an important tissue in pecan nut maturation; it functions as the site for dehiscence and provides markers for cultivar identification.

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Telomere length varies substantially between blood cell types in a reptile

Royal Society Open Science ◽

10.1098/rsos.192136 ◽

2020 ◽

Vol 7 (6) ◽

pp. 192136 ◽

Cited By ~ 3

Author(s):

Mats Olsson ◽

Nicholas J. Geraghty ◽

Erik Wapstra ◽

Mark Wilson

Keyword(s):

Blood Cell ◽

Telomere Length ◽

Whole Blood ◽

Phylogenetic Analyses ◽

Natural Populations ◽

Cell Types ◽

Tissue Type ◽

Telomeric Dna ◽

Blood Cell Type ◽

Widespread Phenomenon

Telomeres are repeat sequences of non-coding DNA-protein molecules that cap or intersperse metazoan chromosomes. Interest in telomeres has increased exponentially in recent years, to now include their ongoing dynamics and evolution within natural populations where individuals vary in telomere attributes. Phylogenetic analyses show profound differences in telomere length across non-model taxa. However, telomeres may also differ in length within individuals and between tissues. The latter becomes a potential source of error when researchers use different tissues for extracting DNA for telomere analysis and scientific inference. A commonly used tissue type for assessing telomere length is blood, a tissue that itself varies in terms of nuclear content among taxa, in particular to what degree their thrombocytes and red blood cells (RBCs) contain nuclei or not. Specifically, when RBCs lack nuclei, leucocytes become the main source of telomeric DNA. RBCs and leucocytes differ in lifespan and how long they have been exposed to ‘senescence' and erosion effects. We report on a study in which cells in whole blood from individual Australian painted dragon lizards ( Ctenophorus pictus ) were identified using flow cytometry and their telomere length simultaneously measured. Lymphocyte telomeres were on average 270% longer than RBC telomeres, and in azurophils (a reptilian monocyte), telomeres were more than 388% longer than those in RBCs. If this variation in telomere length among different blood cell types is a widespread phenomenon, and DNA for comparative telomere analyses are sourced from whole blood, evolutionary inference of telomere traits among taxa may be seriously complicated by the blood cell type comprising the main source of DNA.

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Immunocytochemical demonstration of tissue-type plasminogen activator in endocrine cells of the rat pituitary gland.

The Journal of Cell Biology ◽

10.1083/jcb.101.1.305 ◽

1985 ◽

Vol 101 (1) ◽

pp. 305-311 ◽

Cited By ~ 40

Author(s):

P Kristensen ◽

L S Nielsen ◽

J Grøndahl-Hansen ◽

P B Andresen ◽

L I Larsson ◽

...

Keyword(s):

Growth Hormone ◽

Pituitary Gland ◽

Endocrine Cells ◽

Large Population ◽

Cell Types ◽

Anterior Lobe ◽

Tissue Type ◽

Intermediate Lobe ◽

Posterior Lobe ◽

Rat Pituitary

We immunocytochemically stained rat pituitary glands using antibodies against plasminogen activators of the tissue type (t-PA) and the urokinase type (u-PA). A large population of endocrine cells in the anterior lobe of the gland displayed intense cytoplasmic immunoreactivity with anti-t-PA. In some areas of the intermediate lobe we found a weak staining, and we observed weakly staining granular structures in the posterior lobe. Controls included absorption of the antibodies with highly purified t-PA. In addition, SDS PAGE followed by immunoblotting of pituitary gland extracts revealed only one band with an electrophoretic mobility similar to that of t-PA when stained with anti-t-PA IgG. No u-PA immunoreactivity was detected in the rat pituitary gland. Sequential staining experiments using antibodies against growth hormone and t-PA demonstrated that the t-PA-immunoreactive cells constitute a large subpopulation of the growth hormone-containing cells. These findings represent the first direct evidence for the presence of t-PA in cell types other than endothelial cells in the intact normal organism. In this article we discuss the implications of the results for a possible role of t-PA in the posttranslational processing of prohormones.

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Mouse connective tissue mast cell proteases tryptase and carboxypeptidase A3 play protective roles in itch induced by endothelin-1

Journal of Neuroinflammation ◽

10.1186/s12974-020-01795-4 ◽

2020 ◽

Vol 17 (1) ◽

Author(s):

Elín I. Magnúsdóttir ◽

Mirjana Grujic ◽

Jessica Bergman ◽

Gunnar Pejler ◽

Malin C. Lagerström

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Connective Tissue ◽

Treatment Options ◽

Cell Types ◽

Tissue Type ◽

Human Mast Cell ◽

Knock Out ◽

Endothelin 1 ◽

Deficient Mice

Abstract Background Itch is an unpleasant sensation that can be debilitating, especially if it is chronic and of non-histaminergic origin, as treatment options are limited. Endothelin-1 (ET-1) is a potent endogenous vasoconstrictor that also has the ability to induce a burning, non-histaminergic pruritus when exogenously administered, by activating the endothelin A receptor (ETAR) on primary afferents. ET-1 is released endogenously by several cell-types found in the skin, including macrophages and keratinocytes. Mast cells express ETARs and can thereby be degranulated by ET-1, and mast cell proteases chymase and carboxypeptidase A3 (CPA3) are known to either generate or degrade ET-1, respectively, suggesting a role for mast cell proteases in the regulation of ET-1-induced itch. The mouse mast cell proteases (mMCPs) mMCP4 (chymase), mMCP6 (tryptase), and CPA3 are found in connective tissue type mast cells and are the closest functional homologs to human mast cell proteases, but little is known about their role in endothelin-induced itch. Methods In this study, we evaluated the effects of mast cell protease deficiency on scratching behavior induced by ET-1. To investigate this, mMCP knock-out and transgenic mice were injected intradermally with ET-1 and their scratching behavior was recorded and analyzed. Results CPA3-deficient mice and mice lacking all three proteases demonstrated highly elevated levels of scratching behavior compared with wild-type controls. A modest increase in the number of scratching bouts was also seen in mMCP6-deficient mice, while mMCP4-deficiency did not have any effect. Conclusion Altogether, these findings identify a prominent role for the mast cell proteases, in particular CPA3, in the protection against itch induced by ET-1.

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Expanded equine cumulus–oocyte complexes exhibit higher meiotic competence and lower glucose consumption than compact cumulus–oocyte complexes

Reproduction Fertility and Development ◽

10.1071/rd16441 ◽

2018 ◽

Vol 30 (2) ◽

pp. 297 ◽

Cited By ~ 7

Author(s):

L. González-Fernández ◽

M. J. Sánchez-Calabuig ◽

M. G. Alves ◽

P. F. Oliveira ◽

S. Macedo ◽

...

Keyword(s):

Glucose Metabolism ◽

Granulosa Cells ◽

Glucose Consumption ◽

Cell Types ◽

Solute Carrier Family ◽

Necrosis Factor Alpha ◽

Maturation Rate ◽

Solute Carrier ◽

Meiotic Competence

Equine cumulus–oocyte complexes (COCs) are classified as compact (cCOC) or expanded (eCOC) and vary in their meiotic competence. This difference could be related to divergent glucose metabolism. To test this hypothesis in the present study, eCOCs, cCOCs and expanded or compact mural granulosa cells (EC and CC respectively) were matured in vitro for 30 h, at which time maturation rate, glucose metabolism and the expression of genes involved in glucose transport, glycolysis, apoptosis and meiotic competence were determined. There were significant differences between eCOCs and cCOCs in maturation rate (50% vs 21.7% (n = 192 and 46) respectively; P < 0.001), as well as mean (± s.e.m.) glucose consumption (1.8 ± 0.5 vs 27.9 ± 5.9 nmol per COC respectively) and pyruvate (0.09 ± 0.01 vs 2.4 ± 0.8 nmol per COC respectively) and lactate (4.7 ± 1.3 vs 64.1 ± 20.6 nmol per COC respectively; P < 0.05 for all) production. Glucose consumption in EC and CC did not differ significantly. Expression of hyaluronan-binding protein (tumour necrosis factor alpha induced protein 6; TNFAIP6) was increased in eCOCs and EC, and solute carrier family 2 member 1 (SLC2A1) expression was increased in eCOCs, but there were no differences in the expression of glycolysis-related enzymes and solute carrier family 2 member 3 (SLC2A3) between the COC or mural granulosa cell types. The findings of the present study demonstrate that metabolic and genomic differences exist between eCOCs and cCOCs and mural granulosa cells in the horse.

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Human tissue-type plasminogen activator

Thrombosis and Haemostasis ◽

10.1160/th13-06-0517 ◽

2014 ◽

Vol 112 (08) ◽

pp. 243-254 ◽

Cited By ~ 27

Author(s):

Egbert K. O. Kruithof ◽

Sylvie Dunoyer-Geindre

Keyword(s):

Plasminogen Activator ◽

Gene Transcription ◽

Current Knowledge ◽

Plasminogen Activator Inhibitor ◽

Cell Types ◽

Tissue Type ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator ◽

Central Nervous System Activity ◽

Its Gene

SummaryTissue-type plasminogen activator (t-PA ) plays an important role in the removal of intravascular fibrin deposits and has several physiological roles and pathological activities in the brain. Its production by many other cell types suggests that t-PA has additional functions outside the vascular and central nervous system. Activity of t-PA is regulated at the level of its gene transcription, its mRNA stability and translation, its storage and regulated release, its interaction with cofactors that enhance its activity, its inhibition by inhibitors such as plasminogen activator inhibitor type 1 or neuroserpin, and its removal by clearance receptors. Gene transcription of t-PA is modulated by a large number of hormones, growth factors, cytokines or drugs and t-PA gene responses may be tissue-specific. The aim of this review is to summarise current knowledge on t-PA function and regulation of its pericellular activity, with an emphasis on regulation of its gene expression.

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Soft-Tissue Analogue Design and Tissue Engineering of Liver

MRS Bulletin ◽

10.1557/s0883769400031857 ◽

1996 ◽

Vol 21 (11) ◽

pp. 52-54 ◽

Cited By ~ 5

Author(s):

Prabhas V. Moghe

Keyword(s):

Tissue Engineering ◽

Health Care Cost ◽

Three Dimensional ◽

Cell Types ◽

The United States ◽

Tissue Loss ◽

Tissue Type ◽

Design Parameters ◽

Immune Rejection ◽

Engineered Tissue

Tissue engineering involves the application of physical and life sciences to develop functional substitutes for dysfunctional organs or tissue structures. From an engineering standpoint, tissues contain two basic components—the cells that are organized into proper units, and the material surrounding the cells, called the extracellular matrix (ECM). A third, frequently overlooked feature essential to the maintenance of the activity of the engineered tissue is the three-dimensional architecture of the cell-matrix composite.A comprehensive review of the scope and impact of tissue engineering has previously appeared. Tissue-engineered devices have the potential to reduce the annual health-care cost related to tissue loss and end-stage organ failure to the order of $400 billion, eight million invasive surgical procedures, and 65 million hospital days. A common approach to engineer a functional tissue is to place cells derived from a healthy organ or tissue type (identical or similar to the dysfunctional tissue/organ) on or within matrices analogous to host-tissue ECM. These systems can then be enclosed in appropriate membranes that isolate cells from immune rejection following implantation or can be transplanted directly with the administration of drugs that prevent the immune rejection. Another application of these systems is for extracorporeal (outside the patient's body) device support of a dysfunctional organ. In either instance, the success of the engineered tissue depends critically on the interactions of cells with the tissue analogues. The objective of this article is to outline the simplest matrix-design parameters to control these interactions. While organs are comprised of very different tissue types, for the sake of simplicity, this article is primarily pertinent to the tissue engineering of one major organ, the liver. The choice of this tissue type is intended to serve as a comprehensive generalization of many different cell types since in the diversity and complexity of its activities, the liver has few parallels. The development of an artificial liver is also critically awaited, as in the United States alone, 35,000 people, including the many wait listed for the exorbitant liver organ transplants ($300,000), die each year of chronic liver disorders. In many other countries, liver disease is the second leading cause of death.

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Evidence for carbohydrate-independent endocytosis of tissue-type plasminogen activator by liver cells

Biochemical Journal ◽

10.1042/bj2850799 ◽

1992 ◽

Vol 285 (3) ◽

pp. 799-804 ◽

Cited By ~ 5

Author(s):

E Stang ◽

N Roos ◽

M Schlüter ◽

T Berg ◽

J Krause

Keyword(s):

Plasminogen Activator ◽

Liver Cell ◽

Hepatic Clearance ◽

Mannose Receptor ◽

Cell Types ◽

Tissue Type ◽

Side Chains ◽

Tissue Type Plasminogen Activator ◽

Hepatic Cells ◽

Type Plasminogen Activator

In the liver, tissue-type plasminogen activator (t-PA) is endocytosed by hepatic parenchymal (PC), endothelial (EC) and Kupffer (KC) cells. Although the endocytosis is receptor-mediated, it remains a matter of discussion which receptors are involved in this catabolic process. To evaluate the role of a protein-specific receptor, as well as the possible involvement of the galactose receptor on PC and the mannose receptor on EC, we have employed different glycosylation variants of t-PA in biochemical and immunocytochemical studies. Partial or total removal of carbohydrate side-chains by endoglycosidases did not prevent clearance and hepatic endocytosis of t-PA by either of the liver cell types. Blockade of the galactose and mannose receptors by co-application of a large excess of the glycoprotein ovalbumin remained without effect on the binding and uptake of t-PA by hepatic cells. However, the contribution of different liver cell types to the hepatic clearance of t-PA was to a certain extent dependent on the type of oligosaccharide chains removed. The mannose receptor on EC is partially responsible for the clearance of t-PA by this cell type, whereas the galactose receptor does not seem to be involved in this process. The results obtained in this study further demonstrate that the major portion of the hepatic catabolism of t-PA is independent of its carbohydrate side-chains.

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Light microscopy survey of extant gymnosperm root protophloem and comparison with basal angiosperms

Botany ◽

10.1139/cjb-2013-0284 ◽

2014 ◽

Vol 92 (5) ◽

pp. 388-401 ◽

Cited By ~ 3

Author(s):

Thomas C. Pesacreta ◽

Michael A. Purpera

Keyword(s):

Root Apex ◽

Cell Types ◽

Tissue Type ◽

Root Tip ◽

Chemical Fixation ◽

Physiological Mechanisms ◽

Sieve Elements ◽

Phloem Parenchyma ◽

Extant Species ◽

Large Central Vacuole

Gymnosperm root protophloem is not well understood. There is a question as to whether root protophloem cells mature as phloem parenchyma, or as sieve elements, or if within the protophloem there is an anatomical and evolutionary gradient having characteristics of both cell types. This question is relevant to understanding anatomical and physiological mechanisms that supply nutrients to the root tip. Anatomical data from a broad range of species show that gymnosperms have one to three layers of parenchymatous protophloem cells located at the vascular cylinder periphery between the pericyle and the metaphloem. In some species, these cells are associated with secretory idioblasts. Near the root apex, protophloem cells develop a large central vacuole and, in transverse sections, their radial walls tend to be radially elongated. When mature, these cells are highly longitudinally elongated. Only these cells exhibit surging toward the root apex during chemical fixation. These data indicate that protophloem of gymnosperm roots lacks sieve elements. Because of its distinctive anatomical characteristics and the absence of sieve elements, gymnosperm root protophloem is a vegetative synapomorphy among extant species. The restriction of this tissue type to gymnosperms supports the hypothesis that it originated in a progenitor of that clade.

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The Fetal Allograft Revisited: Does the Study of an Ancient Invertebrate Species Shed Light on the Role of Natural Killer Cells at the Maternal-Fetal Interface?

Clinical and Developmental Immunology ◽

10.1155/2008/631920 ◽

2008 ◽

Vol 2008 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Amy Lightner ◽

Danny J. Schust ◽

Yi-Bin A. Chen ◽

Breton F. Barrier

Keyword(s):

Nk Cells ◽

Natural Killer ◽

Vascular System ◽

Marine Invertebrate ◽

Cell Types ◽

Primary Origin ◽

Uterine Nk Cells ◽

Missing Self ◽

Fresh Insight

Human pregnancy poses a fundamental immunological problem because the placenta and fetus are genetically different from the host mother. Classical transplantation theory has not provided a plausible solution to this problem. Study of naturally occurring allogeneic chimeras in the colonial marine invertebrate, Botryllus schlosseri, has yielded fresh insight into the primitive development of allorecognition, especially regarding the role of natural killer (NK) cells. Uterine NK cells have a unique phenotype that appears to parallel aspects of the NK-like cells in the allorecognition system of B. schlosseri. Most notably, both cell types recognize and reject “missing self” and both are involved in the generation of a common vascular system between two individuals. Chimeric combination in B. schlosseri results in vascular fusion between two individual colonies; uterine NK cells appear essential to the establishment of adequate maternal-fetal circulation. Since human uterine NK cells appear to de-emphasize primary immunological function, it is proposed that they may share the same evolutionary roots as the B. schlosseri allorecognition system rather than a primary origin in immunity.

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Rapid Differentiation of Epithelial Cell Types in Forensic Samples Using Intrinsic Fluorescence and Morphological Signatures

10.1101/245159 ◽

2018 ◽

Author(s):

Emily R. Brocato ◽

M. Katherine Philpott ◽

Catherine C. Connon ◽

Christopher J. Ehrhardt

Keyword(s):

Cell Types ◽

Tissue Type ◽

Fluorescent Properties ◽

Multivariate Statistical ◽

Genetic Profiling ◽

Imaging Flow Cytometry ◽

Statistical Framework ◽

Forensic Samples ◽

Profiling Techniques ◽

Cellular Measurements

AbstractEstablishing the tissue source of epithelial cells within a biological sample is an important capability for forensic laboratories. In this study we used Imaging Flow Cytometry (IFC) to analyze individual cells recovered from buccal, contact epithelial, and vaginal samples that had been dried between 24 hours and more than eight weeks. Measurements capturing the size, shape, and fluorescent properties of cells were collected in an automated manner and then used to build a multivariate statistical framework for differentiating cells based on tissue type. Results showed that cell populations from the three tissue types could be differentiated using a Discriminant Function plot of IFC measurements. Epidermal cells were distinguished from vaginal and buccal cells with an average classification accuracy of ~94%. Ultimately, cellular measurements such as these, which can be obtained non-destructively, may provide probative information for many types of biological samples and complement results from standard genetic profiling techniques.

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