C-C2W is the physical cause of cholesterol gallstones

Cholesterol gallstones are made up of cholesterol.H20, traces of body temperature cholesterol, and a cholesterol-cholestanol-water adduct (C-C-2W). For the first time C-C-2W has been chemically and optically located in such gallstones, specifically in the nucleus, in the groove, and on the surface. These findings suggest a novel yet rational theory of cholesterol-stone quantitatively related to prevention and dissolution: (1) Bile is chemically abnormal if cholestanolH2O is present as a foreign unwanted substance. (2) When cholestanol.H2O in portal blood approaches 10(-4) mg/ml, precipitation of C-C-2W occurs in the hepatocytes because it finds sufficient cholesterol.H2O to reach the solubility product of the adduct. The resulting C-C-2W microcrystallites flow with bile down the biliary tree and then seed the supersaturated cholesterol solution in the gallbladder. (3) On the other hand, for concentrations of cholestanol.H2O around 10(-5) mg/ml, C-C-2W precipitation occurs exclusively in the gallbladder. (4) The adduct is the physical cause of cholesterol gallstones since however it arrives in the gallbladder, it produces swift crystallization of cholesterol.H20.     

A new unified theory: C-C-2W is the chemical cause of all so-called cholesterol and cholestanol lipidoses

The water-insoluble cholesterol-cholestanol-water adduct C-C-2W, chemical and physical cause of atherosclerosis and gallstones, has now been found in tendinous xanthoma as well; C-C-2W, and not cholestanol, is the initial compound deposited in hereditary CTX (cerebrotendinous xanthomatosis). From these and other findings it is theorized that what have been termed cholesterol or cholestanol lipidoses should instead be characterized as C-C-2W lipidoses. More than 1 mg of cholestanol . H2O present in the body causes crystallizaion of C-C-2W . This happens when the steroid meets cholesterol . H2O in sufficient concentration to reach a solubility product of 10(-7) mg/ml. In this light the literature can be interpreted to indicate that C-C-2W exerts negative effects on liver, intima tissue, eyes, lungs, and other parts of the body. Those effects include inflammation, cell necrosis, destruction of cell membranes, abnormal growth and, perhaps, neoplastic activity. Up to 200 g of C-C-2W in the body may be tolerated if evenly spread but not if localized in one or two areas only; e.g., the brain or the cardiovascular system. It is estimated that about 1000 g of C-C-2W, even if spread, are beyond the limit of human tolerance.     

Unsteady and three-dimensional simulation of blood flow in the human aortic arch

A three-dimensional and pulsatile blood flow in a human aortic arch and its three major branches has been studied numerically for a peak Reynolds number of 2500 and a frequency (or Womersley) parameter of 10. The simulation geometry was derived from the three-dimensional reconstruction of a series of two-dimensional slices obtained in vivo using CAT scan imaging on a human aorta. The numerical simulations were obtained using a projection method, and a finite-volume formulation of the Navier-Stokes equations was used on a system of overset grids. Our results demonstrate that the primary flow velocity is skewed towards the inner aortic wall in the ascending aorta, but this skewness shifts to the outer wall in the descending thoracic aorta. Within the arch branches, the flow velocities were skewed to the distal walls with flow reversal along the proximal walls. Extensive secondary flow motion was observed in the aorta, and the structure of these secondary flows was influenced considerably by the presence of the branches. Within the aorta, wall shear stresses were highly dynamic, but were generally high along the outer wall in the vicinity of the branches and low along the inner wall, particularly in the descending thoracic aorta. Within the branches, the shear stresses were considerably higher along the distal walls than along the proximal walls. Wall pressure was low along the inner aortic wall and high around the branches and along the outer wall in the ascending thoracic aorta. Comparison of our numerical results with the localization of early atherosclerotic lesions broadly suggests preferential development of these lesions in regions of extrema (either maxima or minima) in wall shear stress and pressure.     

Development and nature of the partition layer in Tilletia caries teliospore walls.

Developing Tilletia caries teliospores were studied with thin sectioning procedures. After the W1 and W2 spore walls are formed, lamellar material begins to form adjacent to the W2 wall layer. The patches of lamellar material become continuous, and additional layers are added. After the W3 wall starts to form, the lamellar material is difficult to see without special staining. The lamellar material makes it difficult to get resins to penetrate the partition layer of teliospore walls.     

The cell wall of Chlamydomonas reinhardtii gametes: Composition,structure and autolysin-mediated shedding and dissolution

The cell walls of Chlamydomonas gametes are multilayered structures supported on frameworks of polypeptides extending from the plasma membrane. The wall-polypeptide catalogue reported by Monk et al. (1983, Planta 158, 517–533) and extended by U.W. Goodenough et al. (1986, J. Cell Biol. 103, 405–417) was re-evaluated by comparative analysis of mechanically isolated cell walls purified from several strains. The extracellular locus of wall polypeptides was verified by in vivo iodogen-catalysed iodination and by autolysin-mediated elimination of the bulk of these polypeptides from the cell surface. Three (w15, w16, w17) and possibly four (w14) polypeptides were located to the most exterior aspect of the wall because of their susceptibility to Enzymobeadcatalysed iodination and their retention by a cell-wall-less mutant. The composition of shed walls stabilised with ethylenediaminetetraacetic acid during natural mating and kinetic analysis of the dissolution of walls purified from a bald-2 mutant demonstrated the rapid and specific destruction of polypeptide w3. Differential solubilisation of wall polypeptides occurred after loss of w3. Wall dissolution, characterised by the generation of fishbone structures from the W2 layer, gave as many as four additional polypeptides. Charged detergents and sodium perchlorate extracted a comparable range of polypeptides at room temperature from mechanically isolated walls, i.e. components of the W4–W6 layers, hot sodium dodecyl sulphate solubilised framework polypeptides, while reducing agent was required to solubilise the W2 layer. A model of wall structure is presented.Abbreviations DTE dithioerythritol - EDTA ethylenediaminetetraacetic acid - M_r relative molecular mass - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis - Tris 2-amino-2-(hydroxymethyl)-1,3-propanediol     

Placing single-molecule T4 lysozyme enzymes on a bacterial cell surface: toward probing single-molecule enzymatic reaction in living cells

The T4 lysozyme enzymatic hydrolyzation reaction of bacterial cell walls is an important biological process, and single-molecule enzymatic reaction dynamics have been studied under physiological condition using purified Escherichia coli cell walls as substrates. Here, we report progress toward characterizing the T4 lysozyme enzymatic reaction on a living bacterial cell wall using a combined single-molecule placement and spectroscopy. Placing a dye-labeled single T4 lysozyme molecule on a targeted bacterial cell wall by using a hydrodynamic microinjection approach, we monitored single-molecule rotational motions during binding, attachment to, and dissociation from the cell wall by tracing single-molecule fluorescence intensity time trajectories and polarization. The single-molecule attachment duration of the T4 lysozyme to the cell wall during enzymatic reactions was typically shorter than the photobleaching time under physiological conditions. Applying single-molecule fluorescence polarization measurements to characterize the binding and motions of the T4 lysozyme molecules, we observed that the motions of wild-type and mutant T4 lysozyme proteins are essentially the same whether under an enzymatic reaction or not. The changing of the fluorescence polarization suggests that the motions of the T4 lysozyme are associated with orientational rotations. This observation also suggests that the T4 lysozyme binding-unbinding motions on cell walls involve a complex mechanism beyond a single-step first-order rate process.     

Structure and chemical composition of endodermal and rhizodermal/hypodermal walls of several species

CWM, isolated cell wall material
ECW, isolated endodermal cell walls
G, guaiacyl monomer
H, p-hydroxyphenyl monomer
HCW, isolated hypodermal cell walls
RHCW, isolated rhizodermal and hypodermal cell walls
S, syringyl monomer
XV, isolated xylem vessels

Endodermal cell walls of the three dicotyledoneous species Pisum sativum L., Cicer arietinum L. and Ricinus communis L. were isolated enzymatically and analysed for the occurrence of the biopolymers lignin and suberin. From P. sativum, endodermal cell walls in their primary state of development (Casparian strips) were isolated. Related to the dry weight, these isolates contained equal amounts of suberin (2·5%) and lignin (2·7%). In contrast, the endodermal cell walls of C. arietinum and R. communis, which were nearly exclusively in their secondary state of development, contained significantly higher proportions of suberin (10–20%) and only traces of lignin (1–2%). The results of the chemical analyses were supported by a microscopic investigation of Sudan III-stained root cross-sections, showing a Casparian strip restricted to the radial walls of the endodermis of P. sativum and well-pronounced red suberin lamellae in C. arietinum and R. communis roots. Compared with recently investigated monocotyledoneous species, higher amounts of suberin by one order of magnitude were detected with the secondary state of development of dicotyledoneous species. Furthermore, the carbohydrate and protein contents of primary (Clivia miniata Reg. and Monstera deliciosa Liebm.), secondary (C. arietinum and R. communis) and tertiary endodermal cell walls (Allium cepa L. and Iris germanica L.) were determined. The relative carbohydrate content of secondary endodermal cell walls was low (14–20%) compared with the content of primary (42–50%) and tertiary endodermal cell walls (60%), whereas the protein content of isolated endodermal cell walls was high in primary (13%) and secondary (8%) and low in tertiary endodermal cell walls (0·9–2%). The results presented here indicate that the quantitative chemical composition of primary, secondary, and tertiary endodermal cell walls varies significantly. Finally, cell wall proteins are described as an additional important constituent of endodermal cell walls, with the highest concentrations occurring in primary (Casparian strips) and secondary endodermal cell walls.     

A brief note on the study of yieldin,a wall-bound protein that regulates the yield threshold of the cell wall

Yielding of plant-cell walls is defined by the mechanical properties of walls such as their extensibility (Φ for in vivo, φ for in vitro cell wall) and yield threshold (Y for in vivo, y for in vitro cell wall). A protein named yieldin, isolated from the cell wall of growing hypocotyls of Vigna unguiculata L. (cowpea), has been demonstrated to regulate the pH dependency of y in the cell wall of the glycerinated hollow cylinder of the cowpea hypocotyl. This mini-review outlines the process of the discovery of yieldin, and also refers to the progress of studies on yieldin: the molecular cloning of yieldin and its immunolocalization in the etiolated cowpea hypocotyl. Electronic Publication     

Localization of calcium ions in wounded characean internodal cells

Ca²⁺ was localized in chemically injured internodal cells of the characean alga Nitella flexilis (L.) Ag. using alizarin red and antimonate precipitation. The presence of Ca²⁺ in the antimonate precipitates was verified by X-ray analysis and EGTA chelation. Callose-containing amorphous wound walls were induced by 0·1 m m chlortetracycline (CTC) and cellulosic fibrillar wound walls were induced by 50 m m CaCl₂. Numerous precipitates were found in the amorphous wound walls and in the adjacent cytoplasm. Precipitates were mainly localized in single membrane-bound cisternae, probably of the endoplasmic reticulum, which accumulate at the wound and become a component of the amorphous wound wall via membrane fusion. In fibrillar wound walls, which do not contain membranous residues, precipitate density was significantly lower and similar to that in the secondary cell wall.
The data suggest that the high Ca²⁺ content of amorphous wound walls is due to incorporation of cytoplasmic Ca²⁺ stores. The possible function of amorphous wound walls in maintaining cellular Ca²⁺ homeostasis is discussed.     

A seasonal cycle of cell wall structure is accompanied by a cyclical rearrangement of cortical microtubules in fusiform cambial cells within taproots of Aesculus hippocastanum (Hippocastanaceae)

Aspects of the structure and ultrastructure of the fusiform cambial cells of the taproot of Aesculus hippocastanum L. (horse chestnut) are described in relation to the seasonal cycle of cambial activity and dormancy. Particular attention is directed at cell walls and the microtubule and microfilament components of the cytoskeleton, using a range of cytochemical and immunolocalization techniques at the optical and electron-microscopical levels. During the dormant phase, cambial cell walls are thick and multi-layered, the cells possess a helical array of cortical microtubules, and microfilament bundles are oriented axially. In the early stages of reactivation, vesicle-like profiles are associated with the cell walls, whereas arrangement of the cytoskeletal elements remains unchanged. In the succeeding active phase, the cell walls are thin, and cortical microtubules form a random array, although microfilament bundles maintain a near-axial orientation. The observations are discussed in relation to the seasonal cycle of wall structure and cortical microtubule rearrangement within the vascular cambium of hardwood trees. It is suggested that the cell-wall thickening at the onset of cambial dormancy, which is associated with the presence of a helical cortical microtubule array, should be considered to be secondary wall thickening, and that selective lysis of this secondary wall layer during cambial reactivation restores the thinner, primary wall found around active cambial cells.     

Studies on vascular permeability in hypertension: action of anthocyanosides

The initial phase of renal hypertension induced by ligature of the abdominal aorta was accompanied by a transient increase in vascular permeability. This permeability increase has not the same intensity in all parts of the organism: it is greater in the skin and in the aorta wall than in the brain vessels. Treatment of rats with a flavonoid-type drug (anthocyanosides of Vaccinium myrtillus) for 12 days before the induction of hypertension kept the blood-brain barrier permeability normal and limited the increase in vascular permeability in the skin and the aorta wall. As previously demonstrated, the collagens of the blood vessel walls play an important role in the control of vascular permeability. Interaction of these collagens with the drug may be partly responsible for the protection against the permeability-increasing action of hypertension observed in the treated animals.     

Remark on some correspondences between the characteristics of the nerve impulse and those of ferroelectric polarization

Ferroelectric polarization currents have characteristics which may be of use in the study of the nerve impulse either directly or indirectly through the suggestion of parallel experiments in the two domains. For example, the “all or none” aspect of the excitation of the nerve impulse can be considered to correspond in some sense to the coercive force required for the reversal of a ferroelectric polarization. The refractory period then corresponds to the lack of a relaxation process in ferroelectric polarization; for a second application of voltage in a given direction does not produce a ferroelectric current; it is necessary that the polarization be reversed by a reversal of voltage. The “heat block” in nerve conduction may correspond to a ferroelectric Curie point at about 40°C. Velocities of propagation of ferroelectric polarization are of the order of magnitude of the velocities of sound and therefore in a range suitable for the interpretation of the observed velocities of nerve impulses. These and other parallels between ferroelectric behavior and the characteristics of the nerve impulse suggest that there may be a useful degree of similarity between the molecular processes responsible for the nerve impulse and those responsible for ferroelectric polarization. *** DIRECT SUPPORT *** A01E2080 00002     

Saccharomyces cerevisiae mannoproteins form an external cell wall layer that determines wall porosity.

A beta-glucanase (Z-glucanase) from Zymolyase was freed from a protease (Z-protease) by affinity chromatography on alpha 2-macroglobulin-Sepharose columns and used to solubilize proteins from isolated cell walls of Saccharomyces cerevisiae. The cell wall proteins were labeled with 125I and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The bulk of the labeled material had very low mobility. Its mannoprotein nature was demonstrated by precipitation with specific antibodies and by conversion to a band with an average molecular weight of 94,000 after incubation with endo-beta-N-acetylglucosaminidase. The intact mannoproteins were hydrolyzed by Z-protease, but were resistant to the enzyme when the carbohydrate was first removed by endo-beta-N-acetylglucosaminidase. In intact cells, lysis of cell walls by Z-glucanase required a previous incubation with z-protease, which led to solubilization of most of the 125I-labeled proteins. Other proteases that did not attack the cell wall mannoproteins were unable to substitute for Z-protease. The specific effect of Z-protease is consistent with the notion that mannoproteins form a surface layer of the cell wall that penetrates the wall to some depth and shields glucans from attack by Z-glucanase. Mannoproteins, however, do not appear to cover the inner face of the cell wall, because isolated cell walls, in contrast to intact cells, were completely solubilized by Z-glucanase in the absence of protease. The function of mannoproteins in determining cell wall porosity was highlighted by the finding that horseradish peroxidase (Mr, 40,000) causes lysis of cells that had been treated with Z-protease. Depletion of mannoproteins by Z-protease also resulted in the disappearance of a darkly stained surface layer of the cell wall, as observed by electron microscopy. Other agents that facilitate cell lysis by Z-glucanase, such as 2-mercaptoethanol, digitonin, and high concentrations of salts, caused little or no solubilization of mannoprotein. We assume that they perturb and loosen the structure of the mannoprotein network, thereby increasing its porosity. The implications of our results for the construction of the yeast cell wall and the anchoring of mannoprotein to the cell are discussed.     

Distribution of pectin and arabinogalactan protein epitopes during organogenesis from androgenic callus of wheat

The distribution of several arabinogalactan protein and pectic epitopes were studied during organogenesis in androgenic callus of wheat. In cell wall of mature and degenerating parenchyma cells, the arabinogalactan epitopes JIM4, JIM14, JIM16 or LM2 were expressed differently according to the cells location. LM2 was observed also in meristematic cells of regenerated shoot buds and leaves. Anti-pectin JIM7 labelled the wall of meristematic cells but fluorescence was strongest in outer walls of surface cells of callus and shoot buds coated by extracellular matrix surface network (ECMSN). During leaves growth the ECMSN disappeared, and JIM7 fluorescence decreased. JIM5 epitope was abundant in the cell walls lining the intercellular spaces of callus parenchyma and in tricellular junctions within regenerated buds and leaves.     

The Development of Green Onion (Allium Fistulosum L. )Embryo and Endosperm

Embryo development of Zhangqiu green onion conforms to the Asterad type and goes through the following stages: proembryo, globular, ellipsoidal, laterally concave, stick-shaped, and curved and mature. The persistent synergid is present until the late globular stage of embryogenesis. Endosperm development of Zhangqiu green onion follows the nuclear pattern. Endosperm cell formation begins at both the micropylar end and the chalazai end of the embryo sac when the embryo is in the late globular stage. Due to the anticlinal wall formation, a layer of free nuclei becomes a layer of “open cells” which lack the inner periclinat wall. The open cells undergo cell division periclinally, and a layer of complete cells is cut off outside and a new layer of open cells inside. The subsequent cell divisions give rise to the endosperm cells centripetally until those from the opposite of the embryo sac meet. The first anticlinal walls arise from the cell plates without phragmoplasts between the free nuclei in interphase. The first periclinal walls are formed by normal cytokinesis. When a few layers of endosperm cells are formed at the micropylar end and the chalazal end of the embryo sac, free cells are present in the central vacuole.     

Polarization Orientation,Piezoelectricity, and Energy Harvesting Performance of Ferroelectric PVDF‐TrFE Nanotubes Synthesized by Nanoconfinement

1D nanostructures of soft ferroelectric materials exert promising potential in the fields of energy harvesting and flexible and printed nanoelectronics. Here, improved piezoelectric properties, energy‐harvesting performance, lower coercive fields, and the polarization orientation of poly(vinylidene fluoride–trifluoroethylene) (PVDF‐TrFE) nanotubes synthesized with nanoconfinement effect are reported. X‐ray diffraction (XRD) patterns of the nanotubes show the peak corresponding to the planes of (110)/(200), which is a signature of ferroelectric beta phase formation. Piezoforce spectroscopy measurements on the free‐standing horizontal nanotubes bundles reveal that the effective polarization direction is oriented at an inclination to the long axis of the nanotubes. The nanotubes exhibit a coercive field of 18.6 MV m^?1 along the long axis and 40 MV m^?1 (13.2 MV m^?1 considering the air gap) in a direction perpendicular to the long axis, which is lower than the film counterpart of 50 MV m^?1. The poled 200 nm nanotubes, with 40% reduction in poling field, give larger piezoelectric d₃₃ coefficient values of 44 pm V^?1, compared to poled films (≈20 pm V^?1). The ferroelectric nanotubes deliver superior energy harvesting performance with an output voltage of ≈4.8 V and power of 2.2 μW cm^?2, under a dynamic compression pressure of 0.075 MPa at 1 Hz.     

Wall Structure and spore Germination in Fusarium culmorum

The conidial and germ-tube walls of Fusarium culmorum (W. G.Smith) Sacc. have been examined by various chemical and electron-microscopetechniques. On the basis of these results and hypothesis isproposed for the organization of these walls. Microchemicaltests indicate the presence of chitin in the walls and suggestthat the mucilaginous layer around the conidium is mainly composedof xylan. Chemical analyses of isolated wall material confirmthe presence of chitin constituents in the wall, and a rylanlayer around the conidium. Furthermore, the wall contains apolypeptide moiety which has a different amino acid compositionfrom the rest of the protein of the cell. Electron microscopestudies of replicas and sections of conidia, germ tubes, andhyphae reveal a layered structure for the wall. The centrallayer is non-microfibrillar and is overlaid on both sides witha layer of randomly orientated microfibrils. The mucilaginouslayer of the conidium obscures the microfibrillar structurebeneath it unless the mucilage is removed by hydrolysis. Theproblem of hyphal growth is discussed on the basis of the structureof germ-tube tips and mature hyphae observed.     

Ultrastructural studies on the cell walls in Fusarium sulphureum.

The cell walls of Fusarium sulphureum have a microfibrillar component that is randomly arranged. X-ray-diffraction diagrams of the microfibrils are consistent with a high degree of crystallinity and show that they are chitin. The chitin microfibrils of the peripheral walls envelop the hyphal apex and extend across the septae. During the first 8h in culture, the conversion of conidial cells to chlamydospores is evidenced by a swelling of the cells and the original microfibrils remain randomly arranged. Within 24h new wall material is deposited as the cells expand and the wall thickens. The new microfibrils are indistinguishable from those of the original conidial cells. After 3 days in culture, the chlamydospores are fully developed and have the characteristic thick wall which is a continuous layer of randomly arranged microfibrils. Chlamydospores maintained in a conversion medium for 8 days have microfibrils identical with those in 3-day-old cultures; thus a further change in the microfibril orientation did not occur during that period. Alkaline hydrolysis of the walls removes most of the electron-dense staining constituents from the inner wall layer and leaves the outer wall layer intact. This treatment also reveals some of the wall microfibrils. An additional treatment of the walls with HAc/H2O2 completely removes the wall components that react positively to heavy metal stains. The results are discussed in relation to the structure of other fungal cell walls.