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PubMed1982

Talc granulomatosis: laboratory findings similar to sarcoidosis.

We studied 6 men who had some combination of dyspnea, abnormal chest radiographs, resting increased alveolar-arterial oxygen gradients, noncaseating granuloma by lung biopsies, increased serum angiotensin-converting enzyme concentrations, positive gallium lung scans, and increased lymphocyte counts by bronchoalveolar lavage. Our patients were suffering from talc granulomatosis secondary to the intravenous injection of suspended, crushed pentazocine tablets. In addition to the above findings, bronchoalveolar lavage revealed birefringent intracellular and extracellular particles consistent with talc. We conclude that talc granulomatosis can mimic the laboratory findings of pulmonary sarcoidosis, but the findings of birefringent particles in the bronchoalveolar lavage fluid by polarized microscopy is a simple laboratory method for confirming a clinical diagnosis.

Adult↗

PubMed2001

Expression of IL-5 alters bone metabolism and induces ossification of the spleen in transgenic mice.

We have developed a transgenic mouse line, NJ.1638, which expresses high levels of IL-5 from T cells, with profound hematological consequences. Eosinophils comprise more than 60% of circulating white blood cells in these animals, with the total peripheral white blood cell counts increasing more than 40-fold relative to wild-type littermates. This extraordinary proliferative capacity is sustained by expanded sites of extramedullary hematopoiesis and is accompanied by multifocal, ectopic bone formation in the spleen. Histology of the splenic nodules revealed the presence of osteoid matrices and osteocytes trapped within mineralized trabecular plates. In addition, polarized light microscopy of calcified tissue sections revealed both woven bone and areas of organized lamellar bone. Morphometric assessments demonstrated that both the growth and mineralization of splenic bone occurred at rates nearly an order of magnitude higher than in skeletal bone. Skeletal bone metabolic parameters were also perturbed. We also observed heterotopic ossification of the spleen and perturbation of skeletal bone homeostasis following adoptive engraftment of transgenic marrow to wild-type recipients. These data suggest that IL-5 overexpression mediates bone formation through the mobilization of marrow-derived osteogenic progenitors and/or the inhibition of recruited osteoclasts.

Animals↗

PubMed1985

Depth of penetration of in vitro root surface lesions.

An acidified gel system was used to produce artificial caries lesions in root surfaces and in enamel. The teeth were exposed to the gel system for two weeks and four weeks, after which the lesions were examined by polarized light microscopy and photographed by standardized techniques. The depths of penetration of the lesions were measured from these standardized photomicrographs. The lesions in root surfaces were deeper than those in enamel for all teeth. After two but not four weeks of exposure in the gel system, the lesions in the root surfaces of anterior teeth were deeper than those in pre-molars.

Aged↗

PubMed1986

Effect of low levels of fluoride in solution on enamel demineralization in vitro.

The effect of low levels of fluoride in solution on in vitro enamel demineralization has been studied. Extracted human teeth were exposed to 0.1 M lactate solutions (at pH 4.3) which were partially saturated with respect to enamel mineral and which contained between 0.004 and 1 ppm fluoride. Enamel demineralization was monitored using SEM and polarized light microscopy. It was observed that, in the absence of fluoride, rapid enamel demineralization occurred, resulting in the formation of cavitations within 72 hours. Using the same demineralizing medium containing as little as 0.024 and 0.054 ppm fluoride, we observed a remarkable protection of the enamel surface. Subsurface enamel demineralization was, however, observed under these conditions as well as in a solution containing 0.154 ppm fluoride. When the demineralizing solution containing 1 ppm fluoride was used, no mineral loss was detected. The observed inhibition of enamel demineralization was also shown to be associated with a significant uptake of fluoride by the enamel mineral. These observations have been noted to correlate with an increase in solution supersaturation with respect to fluoridated apatitic species. The results obtained were found to be consistent with a proposed hypothesis that the net rate of enamel demineralization will be reduced in a demineralizing medium supersaturated with respect to less soluble fluoridated phases, due to the enhancement of the precipitation rate of fluoridated apatitic phases relative to the rate of dissolution of the original enamel surface.

Dental Caries↗

PubMed1990

Root hard-tissue demineralization rate measured by 125I absorptiometry: comparison with lesion-depth measurements.

The aim of the present study was to compare demineralization of root hard tissue, monitored by 125I absorptiometry, with lesion-depth measurements under polarized light microscopy. The intact roots of ten human molars, which had not been exposed to the oral environment, were divided into 39 cementum/dentin blocks and exposed to a buffer solution of pH 4.5 containing 2.2 mmol/L calcium and inorganic phosphate. After demineralization for 3.5, 7, 14, and 21 days, transmission measurements by 125I absorptiometry were performed, and one block from each tooth was taken out of the solution for lesion-depth measurement. The results showed a high degree of correlation (r = 0.952) between lesion depth and change in transmission, with a more rapid increase initially in both variables. A linear relationship with the square root of time was found. Conversion of transmission data to lesion-depth data was possible when this caries model system was used on cementum dentin blocks.

Absorptiometry, Photon↗

PubMed1997

Effects of collagenase on root demineralization.

The role of proteolytic enzymes in the root caries process remains unclear. The aim of this study was to investigate collagenase activity during tooth root demineralization and remineralization in an in vitro demineralization/remineralization pH-cycling model, Human tooth roots were subjected to pH cycling (alternating demineralization and remineralization) in one of two different time cycles for five days. Collagenase at 90, 180, or 360 micrograms per root was placed into either the demineralizing solution or the remineralizing solution in the pH-cycling system. The effects of additional exposure to collagenase before or after pH cycling were also studied. After the exposure, thin sections of the roots were examined histologically by polarized light microscopy. Changes of calcium and phosphate in the solutions were analyzed chemically. Surface erosion occurred only in the groups where collagenase was contained in the remineralizing solution and in which the root samples were exposed to severe demineralization. However, no differences among the control and experimental groups were found in calcium and phosphate changes in the pH-cycling solutions. These findings suggest that collagenase works during the remineralizing phase and predominantly attacks the organic matrix of the root after demineralization. Additional exposure to collagenase before or after pH cycling did not increase surface erosion except for exposure to collagenase in the absence of phosphate following pH cycling.

Calcium↗

PubMed1987

Migration of Teflon after vocal cord injection.

Each of eight mongrel dogs received a 0.5 ml injection of polytef paste into the right vocal fold. These dogs were killed at 1 week, 1 month, 3 months, and 6 months after injection, and a number of organs were examined. Polarizing microscopy was used to examine the upper cervical lymph nodes, lower cervical lymph nodes, mediastinal lymph nodes, abdominal lymph nodes, cerebral cortex, brainstem, lung, liver, spleen, and kidney to determine if migration of polytef had occurred. Examination of these organs revealed that there was consistent migration of polytef particles into the cervical lymph nodes, with the highest incidence occurring in upper cervical lymph nodes on the side of injection. There was no evidence of migration of polytef particles to distant sites. The study shows that polytef particles may migrate to cervical lymph nodes after injection into the larynx; however, there is no evidence of distant migration.

Animals↗

PubMed1997

Amyloid deposits in the gastrointestinal tract of aging dogs.

Pathologic features, immunohistochemical characteristics, and incidence of gastrointestinal amyloid deposition were investigated in 78 canine necropsies, including 43 males and 35 females ranging from 2 months to 20 years of age. In 31 of 78 dogs, amyloid protein was accumulated in or around vessel walls located in submucosal and muscular layers of the alimentary tract and mesenteric tissues. These deposits did not seem to affect the function(s) of the digestive tract histologically. The deposits showed congophilia and green birefringence under polarized microscopy. Transmission electron microscopy revealed randomly arranged amyloid fibrils 6-10 nm in diameter around a blood vessel. Congophilia was retained even after oxidation with potassium permanganate, suggesting that this protein is not the AA form of amyloid. Although immunohistochemical studies were performed using antibodies to canine amyloid apolipoprotein AI and synthetic human beta amyloid peptide, the immunochemical nature of the protein was not determined. The mean ages of both male and female dogs with gastrointestinal amyloid deposition were higher than those of their normal counterparts (P < 0.001), and the incidence of deposition in elderly dogs was higher than that in young dogs (P < 0.005). However, there was no sex predilection with respect to both the mean age of the dogs with deposition and the incidence of occurrence. The mechanism(s) and importance of this form of amyloid deposition remain unclear.

Aging↗

PubMedDate not supplied

Ocular abnormalities in transgenic mice harboring mutations in the type II collagen gene.

PURPOSE: To characterize the morphological changes in the eyes of transgenic mice harboring different mutations in type II collagen gene to elucidate the function of this collagen in the eye, and to find out whether these animals could function as models for the human arthro-ophthalmopathies of the Kniest, Stickler and Wagner types. METHODS: Three genetically engineered mouse lines representing two types of mutations in the triple-helical domain of type II collagen and their nontransgenic littermates used as controls were analyzed on day 18.5 embryonic development. After genotyping by polymerase chain reaction (PCR) and Southern hybridization the embryos were prepared for routine histology. Polarization microscopy was done on hyaluronidase-treated sections. RESULTS: Histological analysis revealed several genotype-dependent abnormalities in the eyes of the transgenic mice. Most striking changes were observed in the vitreous architecture; in one line of mice the vitreous was tightly packed in the posterior region of the vitreous space with thick fibrils, empty cavities and dense membrane-like material. The other mutation resulted in reduced filament density of the vitreous. In the most severely affected phenotype the internal limiting membrane was detached from the retinal layers and was markedly thickened, and the posterior lens capsule was thickened. The anterior chamber was shallow or absent in all transgenic lines but was well formed in the normal animals. Changes were also observed in the lens, corneal and scleral structures. CONCLUSIONS: The ocular changes observed in transgenic mice harboring mutations in type II collagen gene show similarities to the human ocular findings in Kniest dysplasia, and in Stickler and Wagner syndromes. We therefore propose that these animals could serve as models for systematic analysis of vitreoretinal degeneration and other abnormalities, as seen in these syndromes.

Abnormalities, Multiple↗

PubMed2003

Effect of smear layer on root demineralization adjacent to resin-modified glass ionomer.

The cariostatic effect of resin-modified glass ionomer (RMGI) on secondary root caries is well-documented. However, this beneficial effect may be dependent upon the mode of cavity surface treatment. To investigate this relationship, we studied 4 cavity surface treatments prior to the placement of RMGI: no treatment (None), polyacrylic acid (PAA), phosphoric acid (H(3)PO(4)), and Scotchbond Multi-Purpose adhesive (SMP) as a control. Specimens were aged for two weeks in synthetic saliva, thermocycled, and subjected to an artificial caries challenge (pH 4.4). Polarized light microscopy (PLM) and microradiography (MRG) showed significantly less demineralization with the H(3)PO(4) cavity surface treatment as revealed by ANOVA and Tukey's multiple comparisons (p < or = 0.05). Dentin fluoride profiles determined by electron probe microanalysis (EPMA) supported PLM and MRG findings. It may be concluded that removal of the smear layer with phosphoric acid provides significantly enhanced resistance to secondary root caries formation adjacent to RMGI restorations.

Acid Etching, Dental↗

PubMed2006

Laser-fluoride effect on root demineralization.

Although the individual cariostatic effects of laser and fluoride have been shown, the combined effect of CO(2) laser and fluoride on root demineralization remains uncertain and was the main aim of this study. By using a pH-cycling system and Polarized Light Microscopy, we demonstrated the synergistic effect of fluoride combined with CO(2) laser treatment on reducing root demineralization. The mean lesion depths (in microm) for each group were 160 +/- 14 (Control), 113 +/- 8 (Laser treatment alone), 111 +/- 6 (Fluoride treatment alone), and 25 +/- 7 (Fluoride followed by laser treatment). A significant laser-enhanced fluoride uptake, characterized by the ToF-SIMS analysis, was revealed by the 37% and 400% increments in loosely and firmly bound fluorides (both p < 0.002) in laser-irradiated areas, compared with the non-irradiated controls. In conclusion, there is a significant synergistic effect of combined CO(2) laser and fluoride treatment on the inhibition of root demineralization, possibly due to laser-enhanced fluoride uptake in the root.

Carbon Dioxide↗

PubMed2006

Development of tetracycline-serratiopeptidase-containing periodontal gel: formulation and preliminary clinical study.

The purpose of this research was to reduce the polymer concentration and to obtain reasonable viscosity at a lower concentration of pluronic by the addition of a viscosity modifier. A 20% wt/wt pluronic gel was prepared on a weight basis using the cold method. The effect of the amount of tetracycline and Aerosil on gel properties was studied. The gel was evaluated using different parameters: polarizing microscopy, gelation, gel melting, bioadhesivity, viscosity, drug release, and stability of enzyme. An in vivo study was performed to evaluate the clinical efficiency of the liquid crystalline gel. Addition of Aerosil to the gel favored hexagonal phase formation. Viscosity and bioadhesivity increased with an increase in the concentration of Aerosil. Release of tetracycline was sustained as the concentration of Aerosil increased. Various clinical parameters confirmed the acceptability and efficiency of this gel system.

Chemistry, Pharmaceutical↗

PubMed2003

Tumoral calcium pyrophosphate dihydrate deposition disease of the ligamentum flavum.

OBJECTIVE: Calcium pyrophosphate dihydrate (CPPD) deposition disease (CPPDD), also known as pseudogout, is rarely known to affect the spine. The purpose of this article is to report our experience with six cases involving massive focal deposition of CPPD crystals in the ligamentum flavum. METHODS: Between January 1998 and June 2002, we treated six patients with CPPDD involving the ligamentum flavum of the cervical and thoracic spine. Their ages ranged from 45 to 70 years. There were five female patients and one male patient. The cervical spine was involved in two cases and the thoracic spine in four. All except one patient presented with an insidious onset of myelopathy. The remaining patient presented with paraplegia after trauma. None of the patients exhibited any systemic features of CPPDD or other metabolic conditions that can lead to CPPD deposition. Plain x-rays often yielded inconclusive results. Computed tomography and magnetic resonance imaging were useful in confirming the diagnoses. Decompressive laminectomy, with removal of the ossified ligamenta flava, was performed for all patients. Polarized-light microscopic examinations of the excised ligamenta flava revealed the characteristic rod-shaped, birefringent crystals. RESULTS: Five of the six patients experienced significant improvements in their myelopathic symptoms after surgery. The remaining patient experienced improvements in sensations but no appreciable improvement in motor power. During the follow-up periods, which ranged from 7 months to 3 years, none of the patients presented with a recurrence of CPPD crystal deposition at the previously treated level. However, one patient who exhibited improvement after surgery presented 2 years later with a recurrence of myelopathic features attributable to ossification of the ligamentum flavum at a new level. CONCLUSION: Tumoral CPPDD of the ligamentum flavum is rare. It commonly occurs among middle-age or elderly female patients and presents with progressive myelopathy. Computed tomography and magnetic resonance imaging are complementary in the diagnosis of this condition. Surgery, if performed early, leads to good improvement. However, long-term follow-up monitoring of these patients is necessary, because surgery provides only symptomatic relief and does not treat the underlying disease. With the increasing availability of magnetic resonance imaging, ossification of the ligamentum flavum is being more frequently recognized. In every case of ossified ligamentum flavum, the excised specimen should be examined with polarized-light microscopy. We think that this simple, inexpensive method will lead to the recognition of more cases of spinal CPPDD.

Aged↗

PubMed1991

Kinetochore function can be altered by ultraviolet microbeam irradiation without loss of the associated birefringent spindle fibre.

We have irradiated kinetochores of chromosomes in spermatocytes of crane flies (Nephrotoma abbreviata (Loew)) and Nephrotoma suturalis (Loew), while observing the cells using polarization microscopy. Irradiation of a kinetochore of one sex chromosome with 0.106 ergs microns-2, the minimum dose needed to stop movement, had no effect on the birefringence of the irradiated kinetochore's spindle fibre. Irradiation of the kinetochore of an autosomal half-bivalent in anaphase, with the same dose, had no effect on the birefringence of the irradiated kinetochore's spindle fibre, but nonetheless the anaphase movements of all six autosomal half-bivalents were stopped, temporarily, for up to 20 min. Irradiations of the kinetochores of an autosomal half-bivalent with higher doses (0.301 ergs microns-2) caused loss of birefringence of the irradiated kinetochore's spindle fibre, and the movements of all six autosomal half-bivalents were stopped permanently. We argue that the ultraviolet microbeam differentially affects two functions of the kinetochore: (1) a 'signalling' function, and (2) microtubule attachment, with the signalling function being altered at doses lower than that of microtubule attachment.

Animals↗

PubMed1992

Hydrolysis of lipid droplets in acid cholesteryl-esterase-deficient fibroblasts.

The mechanisms of hydrolysis and accumulation of cholesteryl oleate-lipid droplets prepared in vitro were studied in acid cholesteryl-esterase-deficient fibroblasts (GM00863, GM03111). Acid cholesteryl esterase activity was reduced in both GM00863 and GM03111 (8.9% and 17.4% of the normal level, respectively), while neutral cholesteryl esterase activity was highly stimulated in GM03111. The hydrolysis of [14C]-cholesteryl oleate-lipid droplets in GM00863 was almost as efficient as in normal cells, while that in GM03111 was highly stimulated. When viewed by polarized microscopy the lipid droplets which had accumulated in the mutant cells showed anisotropic liquid crystalline structures. As in normal cells, some of these lipid droplets were observed by transmission electron microscopy as membrane-free lipid inclusion bodies in the cytoplasm. These results suggest that lipid droplets internalized into phagolysosomes of these mutant cells transferred to the cytoplasm, and were hydrolyzed there probably by neutral cholesteryl esterase.

Cells, Cultured↗

PubMed1989

Physical and chemical changes of medicinals in mixtures with adsorbents in the solid state. II. Application of reduced pressure treatment for the improvement of dissolution of flufenamic acid.

Flufenamic acid (FFA) was mixed with magnesium aluminum silicate (MAS) and stored at 60 degrees C at a reduced pressure of about 2.5 mmHg. After storage, when its concentration was not more than 20%, FFA was observed by X-ray diffraction and polarizing microscopy to be amorphous. The dissolution of FFA was thus enhanced in comparison with that of a freshly prepared mixture. Furthermore, the dissolution curves showed a typical supersaturation pattern, and the supersaturation state continued longer, the higher the pH value of the dissolution medium. Flufenamic acid, in a mixture with MAS, became amorphous more rapidly at reduced pressure than at atmospheric pressure, and therefore the effect of improved dissolution appeared earlier at reduced pressure. Infrared spectral studies suggested that FFA, after storage at a reduced pressure with MAS, was dispersed monomolecularly in an ionic form. The technique of treating crystalline medicinals, that have poor solubility in water, with adsorbent at reduced pressure may be useful for improving their dissolution characteristics.

Adsorption↗

PubMed1991

Influence of isosorbide dinitrate concentration on its skin permeability from adhesive matrix devices.

Adhesive matrix devices containing a model drug, isosorbide dinitrate (ISDN), were prepared with three different types of pressure sensitive adhesives (PSAs). ISDN permeation through excised hairless rat skin from the different devices was measured in vitro. For each PSA type, the steady state permeation rate of ISDN increased proportionally with an increase of ISDN concentration in the PSA and reached a maximum level at a certain concentration. Although the concentrations reaching the maximum skin permeation level varied among PSA types, the maximum rate for each PSA type was largely similar to that for ISDN aqueous suspension. The release rate of ISDN from devices was too fast to influence the skin permeation rate for all devices. In the PSA of devices showing maximum skin permeability, ISDN crystalline was observed by polarizing microscopy and differential scanning calorimetry. These results suggest that the skin permeation of ISDN from adhesive matrix devices was controlled by the thermodynamic activity of the drug in the PSAs.

Adhesiveness↗

PubMed2001

Formation of large DNA aggregates induced by spermidine.

The formation of large DNA aggregates induced by spermidine was investigated by UV absorptiometry and polarizing microscopy. The present results reveal that it is stepwise and involves the following morphological variations: fiber, fiber bundles, and a highly condensed phase. Furthermore, the influence of DNA concentration on not only the spermidine concentration required for the DNA aggregation but also the concentration of free spermidine during the aggregation is analyzed.

Journal Article↗