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PubMed1981

Supravital observation of in vitro basophils in immunological reactions.

The migration velocity and morphology of basophils in vitro were examined after the addition of anti-immunoglobulin (anti-IgE or anti-IgG). In atopic asthma patients with high serum IgE levels (more than 1000 i.u./ml) basophils showed increased migration velocity and showed pear-shaped and palmate processes after the addition of anti-IgE, but on the addition of anti-IgG, these basophils did not show increased migration velocity or morphological changes. In intractable asthma patients with low serum IgE levels, these changes occurred with anti-IgG but not with anti-IgE. These in vitro findings suggest a basophil reactivity to anti-IgE and anti-IgG in individual patients and support our previous differentiation of asthma patients according to basophil reaction.

Antibodies, Anti-Idiotypic↗
PubMed1992

Modes of Helicobacter colonization and gastric epithelial damage.

A total of 144 gastric biopsies colonized by Helicobacter-like organisms were studied under light and differential interference contrast microscopy for the modes of bacterial colonization. Biopsies were also graded for the degree of epithelial damage (epithelial-damage-grade: 0 to 6, in ascending order of severity) and density of Helicobacter-like organism (Helicobacter-grade: 0 to 6, in ascending order of bacterial density). Three modes of colonization were identified: free-in-mucus, surface-adhesion and intercellular colonization. Because light microscopy cannot definitely prove the presence of intracellular colonization, bacteria located between cells and below the apical cell border were counted together as intercellular colonization. Bacteria free-in-mucus were seen in all biopsies. Surface adhesion was seen in 50-87.9% of biopsies, without obvious correlation with the epithelial-damage- and Helicobacter-grades. The incidences of intercellular and intracellular colonization were directly proportional to the epithelial-damage- and Helicobacter-grades. Free-in-mucus as the predominant mode of colonization was mainly seen in biopsies with lower (1-3) epithelial-damage- and Helicobacter-grades. Conversely, biopsies with intercellular colonization as the predominant mode of colonization were mainly cases with higher (4-6) epithelial-damage- and Helicobacter-grades. In cases showing predominantly bacteria between cells, 69.2% had a gastric ulcer whereas only 38.8% of cases showing predominantly bacteria free-in-mucus showed ulceration (P < 0.01). These results indicate that Helicobacter-like organisms can invade and penetrate between epithelial cells. When free-in-mucus, Helicobacter-like organisms are less likely to induce epithelial damage. However, the more invasive modes of colonization (intercellular) were associated with severe epithelial damage and high Helicobacter density.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1979

Microphotometric techniques in intravital microcirculatory studies.

Intravital microscopic techniques were developed in order to measure plasma proteins: (1) circulating in the streaming blood of microcirculatory vessels of the exposed rat mesentery, (2) permeating the vessel wall, and (3) moving through the perivascular interstitial tissue. By means of the ultramicrospectrophotometry, the absorbance of proteins containing aromatic amino acids at 280 nm is measured. Absolute amounts of proteins in the range of picograms are measured in a circular measuring field with a diameter of 17 micrometers. Problems of calibration and of unspecific light scattering are discussed. The scanning microfluorometry makes use of the fluorescent labelling of the plasma proteins. Interstitial tissue with a capillary vessel containing labelled proteins is measured at high speed. A motor-driven object stage synchronized with a measuring system uses scanning lines to traverse the tissue. The data are then processed by a computer. In this way we get continuous quantitative information about the dynamics of protein permeability, starting from time zero. The measuring of the fluorescence intensity and the speed of the fluorometric system are further improved by a computerized 10 kHz scanning device.

Animals↗
PubMed1987

Estimation of organelle water fractions from frozen-dried cryosections.

Local dry mass or water fractions can be measured on frozen-dried cryosections assuming constant section thickness in the hydrated state and no net water movements and no differential shrinkage during freezing and drying. These assumptions have been tested on a model consisting of isolated rat liver mitochondria in an albumin matrix with a concentration similar to the dry mass concentration of the cytoplasm. The dry mass concentrations of mitochondria before freezing as measured by interference microscopy and after freezing and freeze-drying of the sections as measured by X-ray microanalysis and scanning microdensitometry are shown to be equal as long as the ice crystals in the medium are smaller than about 100 nm. It is concluded, therefore, that the above-mentioned assumptions could also hold for the cryopreparation of cells and tissues.

Animals↗
PubMed2006

Gliding motility and polarized slime secretion.

Myxococcus leaves a trail of slime on agar as it moves. A filament of slime can be seen attached to the end of a cell, but it is seen only at one end at any particular moment. To identify genes essential for A motility, transposon insertion mutations with defective A motility were studied. Fifteen of the 33 mutants had totally lost A motility. All these mutant cells had filaments of slime emerging from both ends, indicating that bipolar secretion prevents A motility. The remaining 18 A motility mutants, also produced by gene knockout, secreted slime only from one pole, but they swarmed at a lower rate than A(+) and are called 'partial' gliding mutants, or pgl. For each pgl mutant, the reduction in swarm expansion rate was directly proportional to the reduction in the coefficient of elasticotaxis. The pgl mutants have a normal reversal frequency and normal gliding speed when they move. But their probability of movement per unit time is lower than pgl(+) cells. Many of the pgl mutants are produced by transposon insertions in glycosyltransferase genes. It is proposed that these glycosyltransferases carry out the synthesis of a repeat unit polysaccharide that constitutes the slime.

Bacterial Proteins↗
PubMed2006

Micro-anatomical response of cartilage-on-bone to compression: mechanisms of deformation within and beyond the directly loaded matrix.

The biomechanical function of articular cartilage relies crucially on its integration with both the subchondral bone and the wider continuum of cartilage beyond the directly loaded contact region. This study was aimed at visualizing, at the microanatomical level, the deformation response of cartilage including that of the non-directly loaded continuum. Cartilage-on-bone samples from bovine patellae were loaded in static compression until a near-equilibrium deformation was achieved, and then chemically fixed in this deformed state. Full-depth cartilage-bone sections, incorporating the indentation profile and beyond, were studied in their fully hydrated state using differential interference contrast microscopy. Morphometric measurements of the indented profile were used in combination with a force analysis of the tangential layer to investigate the extent to which the applied force is attenuated in moving away from the directly loaded region. This study provides microscopic evidence of a structure-related response in the transitional zone of the cartilage matrix. It is manifested as an intense chevron-type shear discontinuity arising from the constraints provided by both the strain-limiting articular surface and the osteochondral attachment. The discontinuity persists well into the non-directly loaded continuum of cartilage and is proposed as a force attenuation mechanism. The structural and biomechanical analyses presented in this study emphasize the important role of the complex microanatomy of cartilage, highlighting the interconnectivity and optimal recruitment of the load-bearing elements throughout the zonally differentiated cartilage depth.

Animals↗
PubMed1988

Observation of two structures of the tear film lipid layer.

The behaviour of the tear film exposed to the atmosphere for a relatively long time was observed by means of a Nomarski microscope and the Zeiss slit-lamp microscope SL 75. It was observed that the lipid layer of the tear film on the naked eye as well as over the contact lens consists of two structures: the homogeneous structure and a structure exhibiting a micelle-like one. The phenomenon is explained in terms of the specific properties of the different lipids in the gland secretions.

Color↗
PubMed2004

White particulate matter found in blood collection bags consist of platelets and leukocytes.

BACKGROUND: In late January 2003, some blood centers and hospitals throughout the US voluntarily sus-pended the use of some RBC and plasma units for trans-fusion due to the presence of unknown white particulate matter (WPM) in these units. To better understand the WPM phenomena, a number of technologies were used to establish the nature of the particulates observed in Terumo Collection sets. STUDY DESIGN AND METHODS: All AS-5 nonleuko-reduced RBCs and plasma units were visually inspected for WPM by placing the bags on a flat counter, undisturbed, for approximately 10 minutes and then perform-ing a visual examination for particles. Particles were isolated and placed on microscope slides or in plastic tubes for further analysis. Electron microscopy, bright field microscopy, differential interference contrast microscopy, infrared spectroscopy, and flow cytometry procedures were performed to establish the nature of the particulate matter. In addition, leukoreduction filters and blood transfusion sets were used on RBCs units with WPM. RESULTS: The particles were mostly composed of PLTs and WBCs, and fragments of these cells. All macroscopic WPM was removed from RBCs with leukoeduction and transfusion filters. CONCLUSIONS: WPM originated from PLTs and WBCs. Foreign matter (e.g., plastic) was not observed in any of the units. Leukoreduction and transfusion filters can be used to remove macroscopic WPM.

Blood Platelets↗
PubMedDate not supplied

Morphology and infraciliature of a marine scuticociliate with a polymorphic life cycle: Urocryptum tortum n. gen., n. comb.

A new genus and species combination are proposed for Urocryptum tortum n. gen., n. comb., a scuticociliate with a polymorphic life cycle. This marine ciliate was isolated from a sample taken at Gokasho Bay in Mie Prefecture (Japan). Specimens from different phases of the growth cycle were examined in vivo and with two silver staining techniques. Three life-history stages were observed: an exponential growth phase stage (trophont), a stationary phase stage (tomite), and finally a resting stage (cyst). The exponential growth form is laterally flattened and ovoid; it has 20-24 somatic kineties (SK) and a typical complement of scuticociliate oral structures. Polykinetid 1 (Pk1) has two longitudinal files of 6 kinetosomes (Ks); sometimes one or two additional kinetosomes are located anteriorly. Polykinetid 2 (Pk2) has two files of 6 or 7 Ks; a third file of three widely spaced kinetosomes is located on its right side, as well as a small curved row of 5 Ks positioned on the right hand side of the posterior end of Pk2. Polykinetid 3 (Pk3) has 3 rows of 4, 5, and 7 Ks's perpendicular to the haplokinety (Hk) or paroral membrane. The stationary growth phase cell is spindle-shaped and has a similar number of SK that are much more closely spaced than in exponentially growing specimens. Oral infraciliary structures are reduced in size, having fewer kinetosomes and being positioned more anteriorly in the cell. Pk1 is composed of two files of 5-Ks, Pk2 has only two files of 6-7 Ks, and Pk3 has two to three rows of 3-4 Ks. The Hk is displaced anteriorly and becomes straight, losing the shape typical of exponential growth phase cells. Cysts are pyriform with a wide cyst wall; no infraciliary structures were visible.

Animals↗
PubMedDate not supplied

Actin-based motility in the net slime mould Labyrinthula: evidence for the role of myosin in gliding movement.

In contrast to crawling movement (e.g. in amoebae and tissue cells) the other major class of substratum-associated motility in eukaryotes, gliding, has received relatively little attention. The net slime mold Labyrinthula provides a useful laboratory model for studying this process since it exhibits a particular kind of gliding in its plasmodial stage. Here nucleated spindle cells glide along self-established cytoplasmic trackways in a predominantly unidirectional manner, at 1-2 microm/s. These trackways, upon which gliding is dependent, are held by filopodial tethers some distance off the well-developed reticulopodial mesh anchoring the plasmodium onto the substratum. Reflection interference microscopy resolves this matrix in live plasmodia. The axially disposed cytoskeletal elements of the trackways are revealed by rhodamine-labelled phalloidin to be rich in F-actin. A weft of peripheral, rapidly extending filopodia (50 microm/min) typifies the expanding regions of the plasmodium. Here spindle cells are recruited before emigrating into newly differentiated trackways. Immunoblotting whole plasmodia or a sucrose-soluble cytoplasmic extract reveals a single actin-positive band of Mr 48 kDa. Polyclonal antibodies to two distinct myosin peptide sequences identify a single myosin HC (Mr 96 kDa) in immunoblots. Gliding was reversibly blocked by 10 mM 2,3-butanedione-2-monoxime, a myosin ATPase inhibitor, but it was insensitive to the actin-binding drugs cytochalasin D and phalloidin. We suggest that the force (>50 pN) for gliding motility results from interaction of myosin molecules, associated with the spindle cells, with trackway F-actin via the bothrosomes.

Actins↗
PubMed2006

Characterization of acid-tolerant H/CO-utilizing methanogenic enrichment cultures from an acidic peat bog in New York State.

Two methanogenic cultures were enriched from acidic peat soil using a growth medium buffered to c. pH 5. One culture, 6A, was obtained from peat after incubation with H(2)/CO(2), whereas culture NTA was derived from a 10(-4) dilution of untreated peat into a modified medium. 16S rRNA gene clone libraries from each culture contained one methanogen and two bacterial sequences. The methanogen 16S rRNA gene sequences were 99% identical with each other and belonged to the novel "R-10/Fen cluster" family of the Methanomicrobiales, whereas their mcrA sequences were 96% identical. One bacterial 16S rRNA gene sequence from culture 6A belonged to the Bacteroidetes and showed 99% identity with sequences from methanogenic enrichments from German and Russian bogs. The other sequence belonged to the Firmicutes and was identical to a thick rod-shaped citrate-utilizing organism isolated from culture 6A, the numbers of which decreased when the Ti (III) chelator was switched from citrate to nitrilotriacetate. Bacterial clones from the NTA culture clustered in the Delta- and Betaproteobacteria. Both cultures contained thin rods, presumably the methanogens, as the predominant morphotype, and represent a significant advance in characterization of the novel acidiphilic R-10 family methanogens.

Acids↗
PubMed1983

Influence of plasma proteins on erythrocyte morphology and sedimentation.

The influence of plasma proteins on erythrocytes was studied by interference microscopy, scanning electron microscopy (SEM), and by Westergren erythrocyte sedimentation rate (ESR). Albumin kept erythrocytes dispersed as discoid spheres. Fibrinogen seemed responsible for the rouleaux phenomenon, but needed the co-influence of an immunoglobulin to induce rouleaux type of aggregates and high ESR. IgG, IgA and IgM caused immunologic type of aggregates. Albumin acted synergistically with fibrinogen and immunoglobulins. Normal blood contained a network of rouleaux, which probably explained the low normal ESR. High ESR was either due to rouleaux type aggregates where fibrinogen was dominant, or immunologic type aggregates where IgG, IgA or IgM were dominant proteins. Cold agglutinin disease showed normal blood morphology and normal ESR at 37 degrees C and immunologic type aggregates and high ESR at 25 degrees C.

Blood Proteins↗
PubMed1998

A rapid method for generating cystic forms of Borrelia burgdorferi, and their reversal to mobile spirochetes.

Mobile Borrelia burgdorferi were transferred to distilled water (10(6) per ml). The cultures were observed by dark field microscopy (DFM), interference contrast microscopy (ICM) and transmission electron microscopy (TEM). 95% of the spirochetes were converted to cysts after 1 min, and after 4 h no normal mobile borreliae were observed. When transferred to growth medium (BSK-H), the cysts became smaller and more irregular, and were filled with organic substances. After 1 day, 1-5 thin structures sprouted from the cysts. They continued to grow in both length and thickness until they attained a normal spirochetal structure. Finally, these new-born spirochetes detached from the cysts, by which time their mobility had become normal. The present method for producing large amounts of cystic forms of B. burgdorferi is well suited for further studies of this unique microbe.

Borrelia burgdorferi Group↗