scholarly journals Particle-Rich Cytoplasmic Structure (PaCS): Identification, Natural History, Role in Cell Biology and Pathology

Biomolecules ◽  
2014 ◽  
Vol 4 (3) ◽  
pp. 848-861 ◽  
Author(s):  
Enrico Solcia ◽  
Patrizia Sommi ◽  
Vittorio Necchi ◽  
Agostina Vitali ◽  
Rachele Manca ◽  
...  
2009 ◽  
Vol 36 (2) ◽  
pp. 244-261
Author(s):  
Dale R. Calder

Charles Wesley Hargitt was born near Lawrenceburg, Indiana, USA, and died at Syracuse, New York. After a brief career as a Methodist Episcopal minister, he carried out graduate studies in biology at Illinois Wesleyan University and Ohio University. He served briefly on the faculty at Moores Hill College and later at Miami University of Ohio before receiving an appointment at Syracuse University. Hargitt spent 36 years at Syracuse, and for 21 years was a trustee of the Marine Biological Laboratory, Woods Hole, Massachusetts. His research encompassed animal behaviour, cell biology, development, ecology, natural history, and taxonomy, as well as education, eugenics, and theology, and he wrote or contributed to more than 100 publications in science. Approximately half of these were on Cnidaria, with 41 of them on Hydrozoa. His most important works in hydrozoan taxonomy were on species of the Woods Hole region, the Philippines, and south China. Hargitt was author of three genera and 48 species and subspecies ascribed to Hydrozoa, seven species of Anthozoa, and one species of Cubozoa. Four species of hydroids are named in his honour.


2020 ◽  
Vol 43 ◽  
Author(s):  
Hannes Rakoczy

Abstract The natural history of our moral stance told here in this commentary reveals the close nexus of morality and basic social-cognitive capacities. Big mysteries about morality thus transform into smaller and more manageable ones. Here, I raise questions regarding the conceptual, ontogenetic, and evolutionary relations of the moral stance to the intentional and group stances and to shared intentionality.


Author(s):  
William H. Zucker

Planktonic foraminifera are widely-distributed and abundant zooplankters. They are significant as water mass indicators and provide evidence of paleotemperatures and events which occurred during Pleistocene glaciation. In spite of their ecological and paleological significance, little is known of their cell biology. There are few cytological studies of these organisms at the light microscope level and some recent reports of their ultrastructure.Specimens of Globigerinoides ruber, Globigerina bulloides, Globigerinoides conglobatus and Globigerinita glutinata were collected in Bermuda waters and fixed in a cold cacodylate-buffered 6% glutaraldehyde solution for two hours. They were then rinsed, post-fixed in Palade's fluid, rinsed again and stained with uranyl acetate. This was followed by graded ethanol dehydration, during which they were identified and picked clean of debris. The specimens were finally embedded in Epon 812 by placing each organism in a separate BEEM capsule. After sectioning with a diamond knife, stained sections were viewed in a Philips 200 electron microscope.


Author(s):  
W. Bernard

In comparison to many other fields of ultrastructural research in Cell Biology, the successful exploration of genes and gene activity with the electron microscope in higher organisms is a late conquest. Nucleic acid molecules of Prokaryotes could be successfully visualized already since the early sixties, thanks to the Kleinschmidt spreading technique - and much basic information was obtained concerning the shape, length, molecular weight of viral, mitochondrial and chloroplast nucleic acid. Later, additonal methods revealed denaturation profiles, distinction between single and double strandedness and the use of heteroduplexes-led to gene mapping of relatively simple systems carried out in close connection with other methods of molecular genetics.


Author(s):  
E.L. Benedetti ◽  
I. Dunia ◽  
Do Ngoc Lien ◽  
O. Vallon ◽  
D. Louvard ◽  
...  

In the eye lens emerging molecular and structural patterns apparently cohabit with the remnants of the past. The lens in a rather puzzling fashion sums up its own natural history and even transient steps of the differentiation are memorized. A prototype of this situation is well outlined by the study of the lenticular intercellular junctions. These membrane domains exhibit structural, biochemical and perhaps functional polymorphism reflecting throughout life the multiple steps of the differentiation of the epithelium into fibers and of the ageing process of the lenticular cells.The most striking biochemical difference between the membrane derived from the epithelium and from the fibers respectively, concerns the presence of the 26,000 molecular weight polypeptide (MP26) in the latter membranes.


Author(s):  
K. Jacobson ◽  
A. Ishihara ◽  
B. Holifield ◽  
F. Zhang

Our laboratory is concerned with understanding the dynamic structure of the plasma membrane with particular reference to the movement of membrane constituents during cell locomotion. In addition to the standard tools of molecular cell biology, we employ both fluorescence recovery after photo- bleaching (FRAP) and digitized fluorescence microscopy (DFM) to investigate individual cells. FRAP allows the measurement of translational mobility of membrane and cytoplasmic molecules in small regions of single, living cells. DFM is really a new form of light microscopy in that the distribution of individual classes of ions, molecules, and macromolecules can be followed in single, living cells. By employing fluorescent antibodies to defined antigens or fluorescent analogs of cellular constituents as well as ultrasensitive, electronic image detectors and video image averaging to improve signal to noise, fluorescent images of living cells can be acquired over an extended period without significant fading and loss of cell viability.


Author(s):  
A. Hakam ◽  
J.T. Gau ◽  
M.L. Grove ◽  
B.A. Evans ◽  
M. Shuman ◽  
...  

Prostate adenocarcinoma is the most common malignant tumor of men in the United States and is the third leading cause of death in men. Despite attempts at early detection, there will be 244,000 new cases and 44,000 deaths from the disease in the United States in 1995. Therapeutic progress against this disease is hindered by an incomplete understanding of prostate epithelial cell biology, the availability of human tissues for in vitro experimentation, slow dissemination of information between prostate cancer research teams and the increasing pressure to “ stretch” research dollars at the same time staff reductions are occurring.To meet these challenges, we have used the correlative microscopy (CM) and client/server (C/S) computing to increase productivity while decreasing costs. Critical elements of our program are as follows:1) Establishing the Western Pennsylvania Genitourinary (GU) Tissue Bank which includes >100 prostates from patients with prostate adenocarcinoma as well as >20 normal prostates from transplant organ donors.


Author(s):  
M.G. Baldini ◽  
S. Morinaga ◽  
D. Minasian ◽  
R. Feder ◽  
D. Sayre ◽  
...  

Contact X-ray imaging is presently developing as an important imaging technique in cell biology. Our recent studies on human platelets have demonstrated that the cytoskeleton of these cells contains photondense structures which can preferentially be imaged by soft X-ray imaging. Our present research has dealt with platelet activation, i.e., the complex phenomena which precede platelet appregation and are associated with profound changes in platelet cytoskeleton. Human platelets suspended in plasma were used. Whole cell mounts were fixed and dehydrated, then exposed to a stationary source of soft X-rays as previously described. Developed replicas and respective grids were studied by scanning electron microscopy (SEM).


Author(s):  
Béatrice Satiat-Jeunemaitre ◽  
Chris Hawes

The comprehension of the molecular architecture of plant cell walls is one of the best examples in cell biology which illustrates how developments in microscopy have extended the frontiers of a topic. Indeed from the first electron microscope observation of cell walls it has become apparent that our understanding of wall structure has advanced hand in hand with improvements in the technology of specimen preparation for electron microscopy. Cell walls are sub-cellular compartments outside the peripheral plasma membrane, the construction of which depends on a complex cellular biosynthetic and secretory activity (1). They are composed of interwoven polymers, synthesised independently, which together perform a number of varied functions. Biochemical studies have provided us with much data on the varied molecular composition of plant cell walls. However, the detailed intermolecular relationships and the three dimensional arrangement of the polymers in situ remains a mystery. The difficulty in establishing a general molecular model for plant cell walls is also complicated by the vast diversity in wall composition among plant species.


Author(s):  
Ronald D. Edstrom ◽  
Xiuru Yang ◽  
Mary E. Gurnack ◽  
Marcia A. Miller ◽  
Rui Yang ◽  
...  

Many of the questions in biochemistry and cell biology are concerned with the relationships of proteins and other macromolecules in complex arrays which are responsible for carrying out metabolic sequences. The simplistic notion that the enzymes we isolate in soluble form from the cytoplasm were also soluble in vivo is being replaced by the concept that these enzymes occur in organized systems within the cell. In this newer view, the cytoplasm is organized and the “soluble enzymes” are in fact fixed in the cellular space and the only soluble components of the cell are small metabolites, inorganic ions etc. Further support for the concept of metabolic organization is provided by the evidence of metabolic channeling. It has been shown that for some metabolic pathways, the intermediates are not in free diffusion equilibrium with the bulk liquid in the cell but are passed along, more or less directly, from one enzyme to the next.


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