Removal Efficiency of Radioactive Cesium and Iodine Ions by a Flow-Type Apparatus Designed for Electrochemically Reduced Water Production

The Fukushima Daiichi Nuclear Power Plant accident on March 11, 2011 attracted people’s attention, with anxiety over possible radiation hazards. Immediate and long-term concerns are around protection from external and internal exposure by the liberated radionuclides. In particular, residents living in the affected regions are most concerned about ingesting contaminated foodstuffs, including drinking water. Efficient removal of radionuclides from rainwater and drinking water has been reported using several pot-type filtration devices. A currently used flow-type test apparatus is expected to simultaneously provide radionuclide elimination prior to ingestion and protection from internal exposure by accidental ingestion of radionuclides through the use of a micro-carbon carboxymethyl cartridge unit and an electrochemically reduced water production unit, respectively. However, the removability of radionuclides from contaminated tap water has not been tested to date. Thus, the current research was undertaken to assess the capability of the apparatus to remove radionuclides from artificially contaminated tap water. The results presented here demonstrate that the apparatus can reduce radioactivity levels to below the detection limit in applied tap water containing either 300 Bq/kg of ¹³⁷Cs or 150 Bq/kg of ¹²⁵I. The apparatus had a removal efficiency of over 90% for all concentration ranges of radio–cesium and –iodine tested. The results showing efficient radionuclide removability, together with previous studies on molecular hydrogen and platinum nanoparticles as reactive oxygen species scavengers, strongly suggest that the test apparatus has the potential to offer maximum safety against radionuclide-contaminated foodstuffs, including drinking water.     

Water Supply, Evaporation, and Vapour Diffusion in Leaves

On the basis of experimental results published during the last25 years, but more particularly during the last 5 years andincluding some results presented here, the hypothesis is proposedthat an important portion of the water supply from major veinsin leaves travels within the epidermal tissue to sites of evaporationclose to the stomatal pores. These evaporation sites are innerepidermal walls especially subsidiary and guard cell walls becausethese are closest to air spaces with the highest water vapourdeficits. Less water than is traditionally supposed evaporatesfrom mesophyll cell walls. Low osmotic potentials of guard cells(large negative) are not required in building up high turgorpressures. However, they are required in competing for wateragainst the process of evaporation which causes low matric potentialsto develop in subsidiary and guard cell walls so that guardcolls can maintain the comparatively low turgor pressures whichhave been shown to operate the stomatal apparatus. Traditionalviews about leaf water relations and methods of estimating mesophyllresistances for carbon dioxide diffusion into leaves must bemodified.     

The Uptake of Potassium, Nitrate, Water, and Oxygen by a Maize Root System in Relation to its Size

Using a special apparatus, the uptake of nitrate, potassium,water, and oxygen by a maize plant was recorded at short intervals.After cutting most of the roots, the regrowth of the root systemwas measured in relation to the increase in nitrate, potassium,and water uptake, oxygen consumption of the root system, andleaf growth rate. It has been suggested that when the root surfaceis not limiting nitrate reduction is the rate-limiting processfor nitrate uptake. Differences between nitrate uptake in lightand dark are explained by the influence of light on nitratereduction. Differences in leaf growth rate have been discussedin relation to root resistance and leaf water content.     

An Apparatus for the Study of the Oxygen, Salt, and Water Uptake of Various Zones of the Root, with some Preliminary Results with Vicia Faba

An apparatus is described by means of which it is possible tomeasure quantitatively the oxygen, salt uptake, and water uptakeof adjacent segments of single intact root. It is shown in Vicia Faba that the metabolic activity and nitrogenuptake are highest in the apical segment and decrease in thosemore remote. No consistent results were obtained for differences in the wateruptake of different segments.     

The oral apparatus of Tetrahymena pyriformis, mating type 1, variety 1. I. Solubilization and electrophoretic separation of oral apparatus proteins

The protein composition of the oral apparatus of Tetrahymena pyriformis has been investigated with urea-acrylamide gel electrophoresis. The data show that the oral apparatus is composed of numerous proteins, two of which appear to be microtubule proteins (tubulins 1 and 2).     

The Nature of Water Transport across Frog Skin

A method has been developed for determining simultaneously shortcircuit currents and net water fluxes across frog skin. The basis of the water flux measurement is the determination of changes in weight of a plastic chamber containing the skin and external solution. The accuracy of this method permits net water flows larger than 0.5 mg cm^-2hr.^-1 to be detected, and the apparatus has been used to investigate the relationship between active Na transport and non-osmotic water flow across the skin. Measurement of Na transport and net water influx across completely short-circuited skins provides no good correlation between the two flows. However, skins exhibiting no net water movement in sulfate Ringer displayed an apparent electroosmotic flow of about 40 water molecules per Na ion when depolarizing current densities of 50 and 100 μA cm^-2 are used. It is concluded from this and other evidence that the net water influx across frog skin may be partially electroosmotic in character and that there remains another component of water flow unrelated to active Na transport. A theoretical model, based on irreversible thermodynamics, has been developed to explain the non-osmotic water flow across frog skin.     

Identification and characterization of AtCASP,a plant transmembrane Golgi matrix protein

Golgins are a family of coiled-coil proteins that are associated with the Golgi apparatus. They are necessary for tethering events in membrane fusion and may act as structural support for Golgi cisternae. Here we report on the identification of an Arabidopsis golgin which is a homologue of CASP, a known transmembrane mammalian and yeast golgin. Similar to its homologues, the plant CASP contains a long N-terminal coiled-coil region protruding into the cytosol and a C-terminal transmembrane domain with amino acid residues which are highly conserved across species. Through fluorescent protein tagging experiments, we show that plant CASP localizes at the plant Golgi apparatus and that the C-terminus of this protein is sufficient for its localization, as has been shown for its mammalian counterpart. In addition, we demonstrate that the plant CASP is able to localize at the mammalian Golgi apparatus. However, mutagenesis of a conserved tyrosine in the transmembrane domain revealed that it is necessary for ER export and Golgi localization of the Arabidopsis CASP in mammalian cells, but is not required for its correct localization in plant cells. These data suggest that mammalian and plant cells have different mechanisms for concentrating CASP in the Golgi apparatus.†These authors have contributed equally to the work     

A simple, continuous-flow ultrafiltration apparatus

A continuous-flow, inverted ultrafiltration apparatus has been made, which permits protein solutions to be concentrated rapidly and has allowed the fractionation of some binary model mixtures. A major problem, which prevents such fractionations in conventional apparatus, has been identified. The design avoids shearing and overheating of labile solutions and appears to be suitable for both micro- and macro-scale applications.     

Immuno-electron microscopy of formation,degradation and exocytosis of the ovulation neurohormone in Lymnaea stagnalis

Summary The cerebral caudodorsal cells (CDC) of the pulmonate snail Lymnaea stagnalis are involved in the control of egg laying and associated behaviour by releasing various peptides. One of these is the ovulation hormone (CDCH). The cellular dynamics of this peptide have been studied using an antiserum raised to a synthetic portion of CDCH comprising the 20–36 amino acid sequence. With the secondary antibody-immunogold technique, specific immunoreactivity was found in all CDC. Rough endoplasmic reticulum and Golgi apparatus showed very little reactivity as did secretory granules that were in the process of being budded off from the Golgi apparatus. However, secretory granules that were being discharged from the Golgi apparatus, were strongly reactive. Secretory granules within lysosomal structures revealed various degrees of immunoreactivity, indicating their graded breakdown. Large electrondense granules, formed by the Golgi apparatus and thought to be involved in intracellular degradation of secretory material, were only slightly reactive. In the axon terminals secretory granules released their contents into the haemolymph by the process of exocytosis. The exteriorized contents were in most cases clearly immunopositive.The possibility has been discussed that CDCH is cleaved from its polypeptide precursor within secretory granules during granule discharge from the Golgi apparatus; subsequently, the mature secretory granules would be transported towards the neurohaemal axon terminals where they release CDCH into the haemolymph. Superfluous secretory material would be degraded by the lysosomal system including the large electron-dense granules.     

OBSERVATIONS ON THE RELATIONSHIP OF THE GOLGI APPARATUS TO WALL FORMATION IN THE MARINE CHRYSOPHYCEAN ALGA, PLEUROCHRYSIS SCHERFFELII PRINGSHEIM

The role of the Golgi apparatus in wall formation of vegetative cells of a marine chrysophyte, Pleurochrysis scherffelii, is described. Wall fragments are synthesized within the cisternae of the Golgi apparatus. A single Golgi apparatus is always located at the cell periphery, and the distended cisternae are oriented toward the cell surface. A highly-ordered body found near the inflated cisternae is associated with spherical, membrane-bounded bodies which may be involved in the progressive degeneration of cisternal membranes which release wall fragments. Protoplast movement has been detected by time-lapse cinephotomicrography and is correlated at the ultrastructural level with change in positions of the Golgi cisternae. Wall-synthesizing capacity is greatest during transverse wall formation. Senescent cells lack a Golgi apparatus with inflated cisternae. In addition, wall fragments are not present in the Golgi cisternae at this stage. Zoosporogenesis results in a temporary loss of the wall-forming capacity of the Golgi apparatus; this activity then resumes with the formation of a different morphological entity, the scale. Preliminary quantitative measurements of the turnover capacity of the Golgi apparatus have been made. From these data it has been determined that between 41 and 82 Golgi generations are required to synthesize the cell wall of an actively growing cell; this estimate indicates that approximately one cisterna is produced every 2 min, provided the cell generation time is 3 days. The time-lapse cinephotomicrographic data confirm that the rate of production of Golgi cisternae is at least one cisterna every 2 min.     

Reconstruction of the flagellar apparatus and microtubular cytoskeleton inPyramimonas gelidicola (Prasinophyceae,Chlorophyta)

Summary The absolute configuration of the flagellar apparatus inPyramimonas gelidicola McFadden et al. has been determined and shows identity withP. obovata, indicating that they are closely related. Comparison with the flagellar apparatus of quadriflagellate zoospores from the more advancedChlorophyceae suggest thatPyramimonas may be a primitive ancestral form. The microtubular cytoskeleton has been examined in detail and is shown to be unusual in that it does not attach to the flagellar apparatus. Cytoskeletal microtubules are nucleated individually, and this is interpreted as an adaptation to the methods of mitosis and scale deployment. In view of the primitive nature of these processes, it is proposed that this type of cytoskeletal organization may represent a less advanced condition than that of the flagellar root MTOCs (microtubule organizing centers) observed in theChlorophyceae.     

Water oxidation in photosystem II

Photosynthesis Research - Biological water oxidation, performed by a single enzyme, photosystem II, is a central research topic not only in understanding the photosynthetic apparatus but also for...     

Organization of the ciliary basal apparatus in embryonic cells of the sea urchin,Lytechinus pictus

Summary The basal apparatus of embryonic cells of the sea urchin Lytechinus pictus was examined by transmission electron microscopy and compared with the basal apparatus of other metazoan cells. The basal apparatus in these cells is associated with a specialized region of the apical cell surface that is encircled by a ring of microvilli. The basal apparatus includes several features that are common to all ciliated cells, including a basal body, basal foot, basal foot cap, and striated rootlet. However, a component not seen in the basal apparatus of other species has been observed in these cells. This structure is continuous with the striated rootlet, and its ultrastructure indicates that it is composed of the same components as the rootlet. This structure extends from the junction of the basal body and striated rootlet to the cortical region that surrounds the basal body. Based on its morphology and position, this structure is referred to as a striated side-arm. The striated side-arm is always aligned in the plane of the basal foot. Thus, both of these structures extend from the basal body in the plane of the effective stroke. It is suggested that the striated side-arm serves to stabilize the basal apparatus against force exerted by the cilium.     

Status of two cryptic species, Typhlodromus exhilaratus Ragusa and Typhlodromus phialatus Athias-Henriot (Acari: Phytoseiidae): consequences for taxonomy

Typhlodromus phialatus and T. exhilaratus are morphologically close species. Their differentiation is based on the shape of the insemination apparatus and on idiosomal setae length. However, the setae length values are often intermediate between these two species and do not allow accurate identification. Furthermore, the handful of differences in insemination apparatus shape are also questionable as a means of differentiation. Synonymy between these species has thus been questioned. Three experiments were carried out. Idiosomal seta length measurements, molecular tests and cross experiments were conducted for three populations, identified as T. exhilaratus and T. phialatus according to the shape of their insemination apparatus. The results show that the variation range of seta lengths is great and that these criteria do not allow accurate separation of these populations into two species. However, molecular tests show a species-level nucleotide differentiation between them. Cross experiments confirm this result, showing complete reproduction incompatibility between the mites bearing different insemination apparatus shapes. Therefore, T. exhilaratus and T. phialatus could be considered to be two valid species and the insemination apparatus could be considered as a pertinent diagnostic criterion at the specific level.     

Water Balance in Cucumis Plants, Measured by Nuclear Magnetic Resonance, I

In this paper we demonstrate the study of plant water balanceby the non-invasive measurement of tissue water content andwater flow using proton nuclear magnetic resonance (NMR). Sapvelocity and flux were measured independently in the presenceof an excess of stationary tissue water. The instrumentationdescribed allows automated and unattended measurement of flow-and water content-variables in a well-defined region of theplant over periods of several days, with a time resolution betweensuccessive measurements of c. 5 s. Using this apparatus theeffect of changes in light intensity (day/night rhythm) andrelative humidity on stem tissue water content as well as onthe velocity and flux of xylem sap in the stem were investigatedin a cucumber plant. The results are in agreement with predictionsfrom a simple model for plant water balance, which is basedon water potential, flow rate and resistance to flow. As longas only transpiration is varied, flow rate and water content(or potential) are affected in opposite ways as demonstratedin this paper. In contrast, the model predicts that changesin uptake (resulting from changes in, for example, root resistance)will induce changes in water content and flow in the same direction.An experimental verification of this prediction is given ina subsequent paper, where, in addition, the NMR results arecompared to those obtained with a dendrometer. Key words: Water balance model, Cucumis sativus L., flow, water content, NMR, water balance measurement     

Localization of Mannose, TV-Acetylglucosamine and Galactose in the Golgi Apparatus, Plasma Membranes and Cell Walls of Scenedesmus acuminatus

The localization of lectin binding sites in the Golgi apparatus,plasma membranes and cell walls of Scenedesmus acuminatus wasinvestigated by cytochemical electron microscopy. The lectinsused were concanavalin A (Con A), peanut agglutinin (PNA) andwheat germ agglutinin (WGA), all labeled with gold. Con A-goldparticles were deposited not on the Golgi apparatus, but onthe outer cell-wall layer. PNA-gold and WGA-gold particles weredeposited on distal Golgi cisternae and vesicles derived fromthe Golgi apparatus. Entire cell-wall layers were evenly labeledby PNA-gold. The plasma membrane and cytoplasmic regions closeto the plasma membrane were labeled with WGA-gold. The processingof oligosaccharide in the Golgi apparatus, plasma membranesand cell walls of Scenedesmus acuminatus is discussed in referenceto that reported for animal cells. (Received March 5, 1987; Accepted July 18, 1987)     

A System for the Quantitative Sampling of Shallow Water Benthos

An air lift, operated by a diver-boatman team and permitting rapid excision and automatic sieving of uniform portions of mud, sand, and fine to medium shell hash bottoms, is described. The apparatus can be deployed from a very small boat. It is inexpensive to make and to operate and has been used with great success at depths of not more than five meters.     

The Effect of the Unstirred Layer on Human Red Cell Water Permeability

A study has been made of water entry into human red blood cells under an osmotic pressure gradient. The measurements were made using a rapid reaction stop flow apparatus, whose construction, calibration, and performance are described in detail. Red cell volume changes were determined from 90° scattered light. The permeability coefficient for water entry under a relative isosmolar concentration of 1 to 1.5 was found to be 0.22 ± 0.01 cm⁴/sec osmol, which agrees well with our previously published value. The experiments were also designed to measure the thickness of the unstirred layer around the6 red cells. This was found to be 5.5 ± 0.8 µ under the present experimental conditions. It is concluded that our previously measured permeability coefficient for water entrance under a diffusion gradient does not require correction on account of the unstirred layer.     

The origin of the zymogen granule membrane of the pancreatic acinar cell as examined by ultrastructural cytochemistry of acid phosphatase, thiamine pyrophosphatase, and ATP-diphosphohydrolase activities

Cytochemical distributions of acid phosphatase, thiamine pyrophosphatase, and ATP-diphosphohydrolase activities have been examined on thin sections of rat pancreas and on isolated zymogen-granule membranes. Acid phosphatase was found in the rigid lamellae separated from the Golgi stacked cisternae, in condensing vacuoles, and in the trans-saccules of Golgi apparatus; it was not detected in purified zymogen-granule membranes. Thiamine pyrophosphatase was detected in trans-saccules of the Golgi apparatus, in purified zymogen-granule membranes, and in the plasmalemma of the acinar cell. It was absent in condensing vacuoles. The ATP-diphosphohydrolase activity has a distribution similar to thiamine pyrophosphatase. These observations illustrate the similarity between the trans-saccules of the Golgi apparatus and the membrane of mature zymogen granules and the disparity between the latter membrane and the membrane of the condensing vacuole. They suggest that the condensing vacuole might not be the immediate precursor of the zymogen granule as commonly assumed. An alternative possibility would be that condensing vacuoles would fuse with the trans-saccule (transition) of the Golgi apparatus which in turn would form mature zymogen granules.     

Mutations in BCAP31 Cause a Severe X-Linked Phenotype with Deafness,Dystonia, and Central Hypomyelination and Disorganize the Golgi Apparatus

BAP31 is one of the most abundant endoplasmic reticulum (ER) membrane proteins. It is a chaperone protein involved in several pathways, including ER-associated degradation, export of ER proteins to the Golgi apparatus, and programmed cell death. BAP31 is encoded by BCAP31, located in human Xq28 and highly expressed in neurons. We identified loss-of-function mutations in BCAP31 in seven individuals from three families. These persons suffered from motor and intellectual disabilities, dystonia, sensorineural deafness, and white-matter changes, which together define an X-linked syndrome. In the primary fibroblasts of affected individuals, we found that BCAP31 deficiency altered ER morphology and caused a disorganization of the Golgi apparatus in a significant proportion of cells. Contrary to what has been described with transient-RNA-interference experiments, we demonstrate that constitutive BCAP31 deficiency does not activate the unfolded protein response or cell-death effectors. Rather, our data demonstrate that the lack of BAP31 disturbs ER metabolism and impacts the Golgi apparatus, highlighting an important role for BAP31 in ER-to-Golgi crosstalk. These findings provide a molecular basis for a Mendelian syndrome and link intracellular protein trafficking to severe congenital brain dysfunction and deafness.