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[Report on the capsule dosage and mixing system. 2. Development, design and mode of action of a mixing machine for dental materials measured out in capsules].

The author presents a mixing apparatus for dental materials predosed in capsules. It is characterized by a novel principle of motion and great efficiency, which permits to triturate, in a short time and the best possible manner, all luting and filling materials suited for mechanical mixing, including amalgam alloys. Redrawings of quick-motion pictures illustrate the mixing process in the capsule.

Capsules

[Report on the capsule-dosage and mixing system. 4. Correctness and precision in the dosage of multi-component materials; pre-dosage in daily practice as a preliminary solution to the capsule-dosage and mixing system].

The significance of the factors "accuracy" and "precision" in the preparation of multicomponent materials is outlined with special regard to problems related to dosage. The present technological development permits to shift the responsibility for accuracy and precision to the manufacturers of dental materials. In view of the applicability of the capsule dosing and mixing system, the author presents an intermediate solution (based on the experimental verification of various dosing methods) that permits to benefit from the main advantages of the capsule system in everyday practice prior to the establishment of centralized dosing facilities.

Capsules

Fine structure of the avian muscle spindle capsule.

The capsule of the muscle spindle from the anterior and posterior latissimus dorsi muscles of the adult domestic chicken has been studied with the electron microscope. As in other species, two distinct portions of the spindle capsule are distinguished: an outer capsule and an inner capsule. The outer capsule is structurally similar to and continuous with the perineural epithelium. Outer capsule cells are noted by the abundance of pinocytotic vesicles and a network of 6-7-nm microfilaments. The disposition of these microfilaments is circumferential with respect to the longitudinal axis of the spindle. It is proposed that they may provide a contractile mechanism for the capsule which may be related to the over-all functioning of the spindle during movements of the muscle. The inner capsule is composed of a contiguous network of cells possessing long cytoplasmic processes which envelop the intrafusal fibers and their nerve endings in sensory equatorial regions of the spindle. These cells may elaborate the fibrillar and amorphous extracellular material found in periaxial spindle space. They also possess modified cilia with a "9+0" microtubular pattern. It is suggested that these cilia may behave as sensory transducers, relating fluid changes in the periaxial space to the intrafusal fiber nerve endings. Capillaries of the non-fenestrated variety commonly traverse the outer and inner portions of the capsule and are usually completely surrounded by tenuous overlapping processes of inner capsule cells. These findings suggest that the spindle capsule plays a role as a metabolically-active diffusion barrier to the entrance of substances from the external milieu.

Animals

The form and function of cnidarian spirocysts. 2. Ultrastructure of the capsule tip and wall and mechanism of discharge.

The electron-dense capsule tip (apical cap) of sea anemone and coral spirocysts is of a different structure than the capsule wall. The capsule wall is composed of a double layer of fiber-like materials which cross each other at roughly right angles. The innermost layer is characterized by numerous serrations, the tips of which project into the lumen of the capsule. Within each serration, a band of finely cross-striated material encircles the capsule at right angles to its longitudinal axis. The membrane lining the lumen of the capsule appears to be continuous with the wall of the undischarged thread. The outer capsule wall layer consists of closely spaced microfilaments (cnidofilaments) which are oriented in the longitudinal axis of the capsule. The cnidofilaments appear to merge with the apical cap material. Contrary to some previous reports in the literature, it has been found that spirocysts normally discharge by eversion, as do nematocysts. The relationship of the capsule wall sub-structure to the spirocyst discharge process is discussed.

Animals

Thyroid capsule changes during the development of thyroid hyperplasia in the rat.

Young adult male Fischer rats were fed 0.25% thouracil in a low-iodine diet to produce hyperplasia of the thyroid gland. The capsule of the thyroid gland increased in thickness from approximately one cell in controls to a substantial multilayered structure. Increase in capsule thickness was noted by 3 days. The cell population of the capsule was largely fibroblasts, but during a period within the interval from 14 to 28 days, the capsule tended to be exceptionally thick and contained many mononuclear leukocytes. At later times the capsule was not quite as thick and the leukocytes largely disapproved. Capillaries developed in the capsule probably by sprouting. The capsule growth was so extensive that certain neighboring tissues were often incorporated into the capsule, including arteries, veins, nerves, striated muscle, and lymph nodes. There was some regional specificity in the development of capsular hyperplasia. Connective tissue increased around the thyroid and parathyroid glands but not between them. Connective tissue in partitions with the thyroid gland also increased in thickness, although the extent of accumulation of cells and intercellular matrix was much less than in the capsule.

Animals

Maintenance of physiologic concentrations of plasma testosterone in the castrated male dog, using testosterone-filled polydimethylsiloxane capsules.

Effects of various numbers of polydimethylsiloxane (PDS) capsules filled with testosterone (PDS-T) on plasma testosterone (PT) in castrated male dogs were studied. Dogs were implanted with 1 empty PDS capsule or 1, 3, or 5 PDS-T capsules. Blood samples were collected prior to and after implantation, after castration with capsules in situ, and after capsule removal. The PT was determined in these samples by radioimmunoassay. One empty capsule had no effect on PT concentration; after castration, PT values fell to nondetectable amounts. One PDS-T capsule maintained PT at concentrations above nondetectable amounts after castration, but these concentrations were significantly (P less than 0.05) lower than were preimplantation values. Three or five PDS-T capsules were capable of maintaining PT concentrations in the castrated male dog similar to those concentrations seen in the intact dog.

Animals

A comparison of the bioavailability of digoxin in capsule, tablet, and solution taken orally with intravenous digoxin.

Six healthy volunteers were given five single-dose treatments of 0.40 mg digoxin either intravenously, in liquid form, in conventional tablet form (dissolution rate 76 per cent in 1-hour), or in new capsule preparations containing 0.05, 0.10, or 0.20 mg digoxin per capsule. Serum levels, area under the concentration-time curve, and daily urinary digoxin excretion were measured for six days. Higher serum digoxin levels were seen after ingestion of the capsules than after the tablets, with peak levels for the former being 2.2-2.8 times higher than after tablet digoxin. Bioavailability was assessed further by comparing the area under a six-hour concentration-time curve, and again the capsules gave a consistently higher value than the tablets. In addition, the absorption of 0.40 mg digoxin from any of the capsule preparations was much greater than 0.50 mg digoxin in commercially available tablets. The six-day cumulative urinary digoxin excretion was also greater for the capsules than for the 0.20-mg tablets. In comparison with intravenous digoxin, tablets provide 75 per cent maximum bioavailability, whereas the capsule preparations of digoxin improve the bioavailability of digoxin and the 0.20-mg digoxin capsule is absorbed better than 0.25-mg digoxin tablet.

Adult

Experimental effects on surrounding fibrous capsule formation from placing steroid in a silicone bag-gel prosthesis before implantation.

Soft-gel miniprostheses of silicone were implanted subcutaneously into 75 male rats. Groups of prostheses were preinjected with saline, a commercial form of triamcinolone acetonide, or a suspension of crystalline triamcinolone acetonide. The softness of the prosthesis mound later was measured objectively, and the capsules surrounding the implants were analyzed by histology, SEM, and chemistry, at various intervals up to 120 days after implantation. The control implants developed a normal laminar capsule. With an incidence increasing up to 100 percent at 120 days, the steroid-treated implants were surrounded by capsules lacking an inner membrane. The inner membrane of the laminar capsule had a high protein content (relative to normal tissue) and a relatively reduced collagen content, while the diffuse capsule resulting from the TA treatment had a high protein content and a high collagen content (about the same as normal tissue). No differences were found in the softness of the mounds of the implanted prostheses. The effect of the TA treatment was explained on the basis of its collagenolytic effect, which could gradually erode the normal capsule membrane. Capsule firmness could not be related to the architecture or the protein or collagen content in our findings. We hypothesize that normal capsule firmness may be related to the amount and kind of interconnection between the loose outer zone of connective tissue and the surrounding tissue.

Animals

[Comparative evaluation of methacycline hydrochloride capsules and tablets according to their dissolubility and rate of solution].

Desintegration and dissolution of capsules and tablets of methacycline hydrochloride were studied. The study on solubility of methacycline hydrochliride capsules filled with methacycline granulate or powder according to the same formula showed that the rate of the antibiotic liberation from the capsules filled with the powder decreased during storage while that from the capsules filled with the granulate did not change. Investigation of the effect of the mass packing value in a drop on the antibiotic liberation from the capsules showed that an increase in the packing coefficient above 1.38 resulted in a marked decrease in the rate of methacycline liberation from the capsules filled with the granulate. No correlation between desintegration and dissolution of methacycline capsules and tablets was found.

Capsules

The influence of the otic capsule in ambystomid skull formation.

In the absence of the otic capsule, or in the presence of capsular materials of varying volume or placement, the bones and cartilages of the contiguous skull showed several sorts of responses. A. The parietal and squamosal bones, and possibly the parasphenoid bone and parachordal cartilage apparently used the capsule as a substrate, spreading over its surface. B. The parietal, squamosal, and exoccipital bones, and the quadrate cartilage were displaced when otic capsule material was absent or oversized. C. The squamosal bone developed at first independently of the capsule but was modified in its shape and size by the capsule in later, possibly inductive, response. D. Stresses resulting from paired otic capsules of unequal size bent the parasphenoid bone and the parachordal cartilage through angles of predictable direction relative to the notochord. E. The paired exoccipital bones developed at different rates when one otic capsule was absent or oversized. The results obtained following manipulation of the otocyst indicate the major role of extrinsic (epigenetic) parameters in normal skeletogenesis and emphasize an apparent discrepancy between the normal and potential expansion of a bone.

Ambystoma

Polysaccharide capsule of Escherichia coli: microscope study of its size, structure, and sites of synthesis.

This report describes the structure, size, and shape of the uncollapsed polysaccharide capsule of Escherichia coli strain Bi 161/42 [O9:K29(A):H-], its ultrastructural preservation as well as the filamentous components of the isolated capsular material. In a temperature-sensitive mutant, sites were localized at which capsular polysaccharide is "exported" to the cell surface. The highly hydrated capsule of the wild-type cells was visible in the uncollapsed state after freeze-etching, whereas dehydration in greater than or equal to 50% acetone or alcohol caused the capsule to collapse into thick bundles. This was prevented by pretreatment of the cell with capsule-specific immunoglobulin G; the capsule appeared as a homogeneous layer of 250- to 300-nm thickness. The structural preservation depended on the concentration of the anti-capsular immunoglobulin G. Temperature-sensitive mutants, unable to produce capsular antigen at elevated temperatures, showed, 10 to 15 min after shift down to permissive temperature, polysaccharide strands with K29 specificity appearing at the cell surface at roughly 20 sites per cell; concomitantly, capsule-directed antibody started to agglutinate the bacteria. The sites at which the new antigen emerged were found in random distribution over the entire surface of the organism. Spreading of purified polysaccharide was achieved on air-water interfaces; after subsequent shadow casting with heavy metal, filamentous elements were observed with a smallest class of filaments measuring 250 nm in length and 3 to 6 nm in width. At one end these fibers revealed a knoblike structure of about 10-nm diameter. The slimelike polysaccharides from mutants produced filamentous bundles of greater than 100-microns length, with antigenic and phage-receptor properties indistinguishable from those of the wild-type K29 capsule antigen.

Antigens, Bacterial

Hormonal control of reproduction in Busycon: laying of egg capsules caused by nervous system extracts.

Mature specimens of female Busycon laid egg capsules when injected with extracts of nervous systems of male or female Busycon. The substance causing this behavior, named egg capsule laying substance (ECLS), was found most reliably in parietal ganglia, less consistently in cerebral-pleural ganglia, and rarely in other ganglia. Both species of Busycon found in Woods Hole, B. canaliculatum and B. carica, contained ECLS, and ECLS of each species was active in the other. ECLS activity was not destroyed by boiling for up to fifteen minutes. Centrifugation of nervous system extracts at 105,000 X g yielded ECLS only in the pellet. ECLS was not released from the pellet by freeze-thawing or by 1.0 M NaCl, but could be partially solubilized by boiling extracts before centrifugation. ECLS activity was destroyed by protease. Several animals "spontaneously" laid strings of egg capsules after being put in a group tank with males and other females. Approximately the first ten capsules laid by these animals were devoid of eggs, after which egg-containing capsules were laid. Injection of ECLS into a spontaneous egg layer within a few hours after cessation of spontaneous egg laying caused the laying of capsules containing eggs. The possibility that ECLS may normally be responsible for the laying of both eggs and egg capsules is discussed.

Animals

Timed-release capsule method for coliform enumeration.

Wax-coated capsules containing selective ingredients (brilliant green and oxgall) were added at the time of inoculation of most-probable-number media (modified lactose broths). The inhibitory ingredients gradually diffused from the capsules into the nonselective media, imparting selectivity to the media. Concentrations of brilliant green did not reach inhibitory levels until 2 or more h had elapsed, which permitted repair of some injured cells. Resuscitation of heat-injured Escherichia coli B cells occurred in the capsule-containing media, but not in conventional brilliant green bile 2% broth or violet red bile agar. No statistically significant differences were noted between coliform counts obtained on two groups of water samples by using the capsule, most-probable-number, membrane filtration, and pour plate methods. The capsule method could be used, however, as a combined presumptive and confirmed test for the examination of water. Improvements are needed to adapt the capsule method to the analysis of some categories of food.

Bacteriological Techniques

Ultrastructural immunocytochemical localization of two hydatid fluid antigens (antigen 5 and antigen B) in the brood capsules and protoscoleces of ovine and equine Echinococcus granulosus and E. multilocularis.

The unlabelled antibody method was used in the ultrastructural localization of two hydatid fluid antigens, antigen 5 and antigen B, in brood capsules and protoscoleces of Echinococcus granulosus and E. multilocularis. Antigen 5 was found in the parenchyma cells of the protoscolex and brood capsule wall and to a lesser extent in the walls of the flame cells and collecting ducts of the excretory system and in the surrounding interstitial material. It is suggested that, while some excretion of this antigen may occur from the protoscolex, it could also be liberated into the cystic cavity by degeneration of protoscoleces and parenchymal cells of the brood capsule wall. Antigen B was found mainly in the distal cytoplasm and perinuclear cytoplasm of the tegument anterior to the suckers. It is apparently secreted to the outside and was present in the brood capsule contents; it adheres to the anterior surface and the posterior periodic acid-Schiff (PAS)-positive glycocalyx of the protoscolex and to the inner surface of the brood capsule wall. The protoscolex tegument posterior to the suckers was negative. The parenchyma cells of the protoscolex and brood capsule wall were also positive although the intensity of the reaction product was variable.

Animals

The fine structure of the outer capsule of the snout muscle spindle in the Japanese lesser shrew-mole.

The fine structure of the outer capsule of the snout muscle spindles of the Japanese lesser shrew-mole (42 spindles from 9 animals) was described electron microscopically. The capsule of the snout muscle spindle is composed of 5 to 6 layers of the so-called capsule cells derived from the perineural epithelium of the peripheral nerve which supplies the spindle. The capsule cells revealed the presence of numerous pinocytotic vesicles, granular endoplasmic reticulum, abundant ribosomes, mitochondria, dense bodies, microvesicles and Golgi complex. It would be highly suggestive of their secretory or transporting activity. The various types of plication within the capsule of the muscle spindle were detected in the equatorial region. By means of such projections the functioning surface of the outer capsule has been enormously increased.

Animals

The ultrastructure of the capsule of the neuromuscular spindles from Python reticulatus (Schneid.).

The capsule of the neuromuscular spindles in the lower costocutaneous muscles from Python reticulatus (Schneid.) has been studied at the electron microscope. As in other vertebrate species, the capsule is divisible into 2 components, i.e. an inner and an outer capsule, which display a very similar structure. Moreover, it has been possible to bring to light the continuity of the outer capsule with the cells and fibres of the perineural sheath enveloping the sensory and motory fibres. The capsule cells exhibit a number of pinocytotic vesicles, profiles of granular endoplasmic reticulum, mitochondria, glycogen particles and Golgi complexes. The presence of these structures points to the secretory and transport activities performed by the spindle capsule in the control of the composition of the intracapsular fluid.

Animals