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Results for “Microscopy, Polarization”

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PubMed2005

Effect of topical fluoride and fluoride varnish on in vitro root surface lesions.

PURPOSE: To evaluate the effect of a fluoride varnish on demineralization and remineralization of root surfaces in vitro. METHODS: 80 caries-free teeth were selected from a large pool of extracted anterior and premolar teeth from elderly patients. Acid resistant nail varnish was painted on all surfaces except for a window (l x 4 mm) on the buccal or lingual root surfaces. Teeth were randomly divided into four treatment groups: CONTROL: washed with deionized/distilled water; Daily gel: treated with Karigel-N (5,000 ppm) for 4 minutes daily; Weekly gel: treated with Karigel-N for 4 minutes weekly; and Weekly varnish: treated with Duraflor (22,600 ppm) weekly (the varnish was removed 24 hours after each application). Teeth were then placed in a cycle of demineralization (6 hours at pH 4.3) and remineralization (17 hours at pH 7.0) for 21 days. Half the specimens of each group were brushed with no dentifrice for 10 seconds twice daily. Specimens were evaluated under polarized light microscopy and contact microradiography. The depth of each lesion and width of the remineralization bands were measured. An ANOVA model was used to assess the effect of different treatments. RESULTS: The control group had the deepest lesions and the daily gel group had the shallowest lesions. The weekly varnish group was found to have significantly shallower lesions than the weekly gel group. The varnish brushing subgroup had significantly deeper lesions than varnish non-brushing subgroup (P = 0.01). Remineralization bands were detectable in most lesions. There was no significant difference in band width between different groups (F = 0.634, P = 0.594). However, a significant difference was found when remineralization bands were calculated as percentage of lesion depth between different groups (F = 4.24, P = 0.001). The varnish non-brushing subgroup had significantly higher percentage than the control group, but daily gel non-brushing had the highest percentage. Brushing was a significant factor in the varnish group. Lesions were significantly shallower in the non-brushing varnish subgroup.

Aged↗

PubMedDate not supplied

[Pathomorphology of the endocardium and myocardium in the heart injury].

Light, polarization, luminescent microscopy, phase contrast, special staining methods and scanning electron microscopy were used for studying sections and fragments of the endocardium and myocardium from 123 patients who had died of heart contusion and ischemic heart disease and from 50 rats with experimental heart contusion. The morphological classification of heart contusion and differential-diagnostic table of myocardial alterations due to contusion of the heart and ischemic heart disease are proposed to facilitate pathomorphological diagnosis of heart contusion. The classification of pathomorphological signs in heart contusion is presented.

Adolescent↗

PubMed1975

Septic and crystalline joint disease. A simultaneous occurrence.

Bacteria and crystals were simultaneously recovered from the synovial fluid of two patients with acutely inflamed joints. The bacteria were initially identified on Gram stain and subsequently grown on supplemented peptone broth, and the crystals were readily identified by polarizing microscopy. Although cause-and-effect relationship between these two types of arthritis cannot be established, the need for thorough examination of synovial fluid is evident.

Acute Disease↗

PubMed2005

Hypomagnesemia and chondrocalcinosis in short bowel syndrome.

Chondrocalcinosis is a result of deposition of calcium pyrophosphate dihydrate (CPPD) crystals in cartilage and fibrocartilage. Chondrocalcinosis is usually sporadic but has also been associated with a variety of metabolic diseases including hypomagnesemia. Reported cases of hypomagnesemia associated chondrocalcinosis were mostly due to renal genetic disorders such as Bartter's or Gitelman's syndrome. We describe 3 patients with chronic hypomagnesemia induced by short bowel syndrome who developed symptomatic chondrocalcinosis. CPPD crystals were identified by polarizing light microscopy in one patient. The underlying intestinal pathology was radiation enteritis in 2 patients and mesenteric arterial thrombosis in the third. Our observations strengthen the hypothesis of a role for magnesium in CPPD crystal deposition disease.

Aged↗

PubMed2006

[Joint resurfacing using allograft chondrocytes embedded in alginate gel].

OBJECTIVE: To explore the feasibility of repairing the articular cartilage with allo-articular chondrocytes embedded in alginate gel. METHODS: Allo-articular chondrocytes were isolated from three adult New zealand rabbits. The cells were cultured in DMEM/F-12 supplemented with 20% fetal bovine serum (FBS). Chondrocytes of 2nd - 3rd passage were harvested and were diluted to 5.0 x 10(7) cells/ml with 1.2% alginate. Then alginate gel was formed by 102 mM CaCl(2). The gels were cultured subsequently for 1 week and then transferred to the full-thickness defects in the femoral condyles of adult rabbits. In control group the defects were left untreated. The animals were sacrificed in the 3rd and 6th month after operation respectively. The specimens were decalcified with 50% formic acid. The histologic sections were stained with safranin O-fast green, hematoxylin-eosin (H&E) and picric acid-Sirius red and immunohisto-stained for type II collagen and aggrecan. The repairing efficiency was evaluated according to Wakitani scoring. RESULT: In the experiment group all 8 defects acquired repair, 7/8 were repaired with mature hyaline cartilage tissue, and 1/8 was with fibrocartilage tissue for less cell-gel inputted. The thick of repaired tissues were closed to the normal and the tissue integrated smoothly with cartilage around the defects. Safranin O staining of the matrix acted in accordance with the normal and immunostaining for type II collagen and aggrecan showed positive. Picric acid-Sirius red staining showed that the chondrocytes lined in lines and the collagen aligned like Gothic architecture structure by polarization microscopy. There was no evidence of residue of alginate and inflammation in 3rd month specimens and no obvious deterioration at 6th month. But in control group, only a small amount of fibrous, fibrocartilage, or hyaline-like tissue was seen on the surface of the defects. Wakitani scoring showed 1.75 points for the experiment group and 7.65 for the control group. CONCLUSION: It is a promising way to repair the articular cartilage with homogeneous articular chondrocytes embedded in alginate gel.

Alginates↗

PubMed2006

Fine needle aspiration of tophi in asymptomatic gout--a case report.

Gout, a chronic hyperuricemic crystal induced arthropathy, may produce soft tissue masses (tophi). Tophi may be found in synovial membranes, periarticular ligaments, tendons, soft tissues as well as internal organs. We present a case in which diagnosis of gout was made by fine needle aspiration of tophus. The patient had a painless nodule over right ankle which was progressively increasing in size. He gave a past history of painful arthropathy, but serum uric acid levels were within normal limits. At this juncture, FNAC of the ankle tophus was performed which revealed aggregated and innumerable dissociated needle-shaped negatively birefringent crystals of monosodium urate (MSU) on polarization microscopy.

Ankle↗

PubMed2006

[Effect of radiation sterilization on biomaterial structure and properties].

The purpose of the investigation was the study of structural changes connective tissue biomaterials after different combinations of their radiation sterilization, physico-chemical treatment and conservation. Using a complex of histological methods (polarization microscopy of unstained sections, van Gieson's stain, scanning electron microscopy), an analysis was performed to detect the structural changes in tendons and dermis which underwent various physico-chemical treatment and subjected to the radiation sterilization using different types (3- radiation and fast-moving electron stream) and doses (1.5, 2.5 and 4 Mrad) of radiation. The dependence of the structural changes in the biomaterials on the fibroarchitectonics of the tissue as well as on the physico-chemical treatment and radiation type and dose was demonstrated. The tendons underwent clear-cut significant changes in all regimes and radiation doses studied. Dermis was found to be most resistant to radiation challenge.

Biocompatible Materials↗

PubMed1991

Histopathological changes preceding spontaneous rupture of a tendon. A controlled study of 891 patients.

We evaluated specimens obtained from the biopsy of spontaneously ruptured tendons in 891 patients who were treated between 1968 and 1989. The specimens, which were removed at the time of repair, included 397 Achilles tendons, 302 biceps brachii tendons, forty extensor pollicis longus tendons, eighty-two quadriceps tendons and patellar ligaments, and seventy other tendons. Age and sex-matched control specimens, from 445 tendons taken at the time of death from the cadavera of previously healthy individuals who died accidentally, also were obtained and evaluated. The histopathological analyses of the specimens included light and polarized light microscopy and scanning and transmission electron microscopy. A healthy structure was not seen in any spontaneously ruptured tendon, but two-thirds of the control tendons were structurally healthy (p less than 0.001). There were characteristic histopathological patterns in the spontaneously ruptured tendons. Most (97 per cent) of the pathological changes were degenerative; they included hypoxic degenerative tendinopathy, mucoid degeneration, tendolipomatosis, and calcifying tendinopathy, either alone or in combination. These changes were also found in 34 per cent of the control tendons, but significantly less frequently (p less than 0.001). In the other twenty-six ruptured tendons (3 per cent), the pathological change was an intratendinous foreign body, rheumatoid tendinitis, a xanthoma, a tumor, or a tumor-like lesion such as an intratendinous ganglion. The findings clearly indicate that, at least in an urban population, degenerative changes are common in the tendons of people who are older than thirty-five years and that these changes are associated with spontaneous rupture.

Achilles Tendon↗

PubMedDate not supplied

Nondestructive analysis of mitral valve collagen fiber orientation.

Collagen is the most abundant and highest modulus component in mitral valve (MV) tissue. MV leaflet and chordal collagen ultrastructure were analyzed by small angle light scattering (SALS) and polarized light microscopy (PLM) to provide collagen fiber architecture mapping. It was hypothesized that structural arrangement strongly influences MV tissue mechanical properties and thus physiologic function.

Actin Cytoskeleton↗

PubMedDate not supplied

The evolution of human periodontal tissues with ageing.

In this research, the structural modifications with ageing of clinically healthy periodontal tissues were analyzed by means of polarization microscopy and morphometrical methods for light microscopy. The new findings may be summarized as follows. The periodontal ligament was found to be widened in the cervical and apical regions. The thickening of cementum with ageing was shown to be accompanied by a modification in the shape of Sharpey's fibres, which in the elderlies were wavy instead of straight as in the control. Lamellar bone, forming an osteone, was found to substitute in part for cementum in one tooth. These results are interpreted as indicating that: (1) late active eruption occurs in man, causing the observed modification in the thickness of periodontal ligament and cementum in the apical region and in the direction of Sharpey's fibres within cementum; (2) cementum may undergo renewal during lifetime and in this case bone may be deposited in contact with dentin.

Adolescent↗

PubMed1991

[Maturation of enamel and tooth eruption].

The tertiary maturation of the erupting tooth needs much more time than it is supposed in literature. Possibly the completion is in accord with the decline of the caries activity at the end of the second decade of lifetime. With the aid of polarizing microscopy, electron microprobe, microhardness testing (Vickers) and scanning electron microscopy different stages of posteruptive maturation from human and other mammalian teeth were analysed. The mineralization level in the outer surface of human enamel is completing little by little in more than 5 years after eruption. This state is in the ruminant tooth obvious never within reach in consequence of the specific physiological conditions. The maturating mineralization after our preliminary findings is fundamentally different to remineralization.

Animals↗

PubMed1977

Structure and interactions of lipids in human plasma low density lipoproteins.

Temperature-dependent techniques (differential scanning calorimetry, polarizing microscopy, and x-ray scattering and diffraction techniques) were used to compare the properties of human plasma low density lipoproteins (LDL) with its extracted lipid classes. Three types of thermal transitions were characterized: (a) a reversible transition in intact LDL near body temperature associated with a liquid crystalline order-disorder phase change of cholesterol esters within the particles; (b) an irreversible high temperature transition (approximately 70-90 degrees) associated with LDL denaturation and release of cholesterol esters from the disrupted particles; and (c) low temperature transitions related to liquid crystalline and crystalline phase changes in these released esters. The temperature of the reversible transition in intact LDL varies among individual donors. Correlation analysis shows that the temperature of this transition negatively correlates with the amount of triglyceride relative to cholesterol ester in LDL. Studies on mixtures of cholesterol esters and triglycerides isolated from LDL show a similar effect, increasing amounts of triglycerides decreasing the temperature of the liquid leads to smectic liquid crystalline transition of the isolated esters. Thus, the amount of triglyceride in LDL influences the fluidity of the cholesterol esters in LDL. The enthalpy of the reversible transition in intact LDL is 0.69 cal/g of LDL cholesterol ester. This compares with 0.89 cal/g for the liquid leads to liquid crystalline transition of the cholesterol esters released from denatured LDL and 1.01 cal/g for the same transition in the extracted esters. Unlike the cholesterol esters released from denatured LDL, or isolated LDL esters, cholesterol ester in the intact LDL particle does not crystallize. These findings suggest that the behavior of cholesterol esters in intact LDL is constrained relative to their behavior when freed from the restrictions of the particle. These results together with experiments on partitioning of the individual lipid classes of LDL allow us to define the distribution and interaction of lipids in the intact LDL particle.

Calorimetry↗

PubMed1977

Interaction of cholesterol ester and triglyceride in human plasma very low density lipoprotein.

The properties of human plasma very low density lipoproteins (VLDL), low density lipoproteins (LDL), and their extracted lipids were compared using calorimetric, X-ray scattering, and polarizing microscopy techniques. Intact LDL, and cholesterol esters isolated from LDL and VLDL each undergo reversible changes in their physical state around body temperature. These transitions are associated with ordered liquid crystalline to liquid phase changes of the cholesterol esters. In contrast to LDL, VLDL has no reversible transitions and shows no evidence of ordered liquid crystalline structures between 10 and 45 degrees C. Therefore, unlike LDL, VLDL does not contain a separate cholesterol ester region capable of undergoing cooperative melting. Solubility studies at 37 degrees C of cholesterol esters and triglyceride isolated from VLDL show that even at a weight ratio of 1:1, which greatly exceeds the relative amount of cholesterol esters in VLDL, cholesterol ester is completely soluble in triglyceride. Thus, the cholesterol ester in VLDL is not sequestered in a separate domain within VLDL, but is dissolved in the liquid core of the particle.

Binding Sites↗

PubMed1990

[What is new in genetically-induced hair diseases?].

A profound knowledge of specific genetically determined anomalies of the hair may be of considerable value in the diagnosis of genetic syndromes. We give a review of a few recent developments in the field of genetic hair diseases. For example, the brittle hair due to sulphur deficiency (trichothiodystrophy) is nowadays regarded as genetically heterogeneous; three different syndromes can be distinguished: BIDS syndrome, Tay syndrome, and PIBIDS syndrome. Polarization microscopy revealed a striking resemblance of the hair anomalies found in trichothiodystrophy syndromes and those in acrodermatitis enteropathica. This surprising result indicates similar pathophysiological mechanisms. The Comèl-Netherton syndrome--long regarded as representing two different diseases--has recently been recognized as a clinically variable, but genetically homogeneous syndrome, which is most likely based on a single mutation ("lumping"). Minor's sweat test allows the recognition of women heterozygous for X-linked hypohidrotic ectodermal dysplasia and may help to appreciate seemingly non-specific hair findings, such as diffuse alopecia.

Ectodermal Dysplasia↗

PubMed1990

[A method of individual selection of cholelitholytic drugs for the treatment of cholelithiasis].

A method of individual selection of cholelitholytic agents was developed and tested in the clinic on the grounds of the findings of polarizing microscopy of bile and the results of study of gallstones by scanning electron microscopy. Its essence consists in visual appraisal of the effect of various solvents, used in the clinic, on the crystal structures of the patient's bile. The use of the developed method makes it possible to raise significantly the efficacy of contact solution of gallstones in combined treatment of cholelithiasis.

Aged↗

PubMedDate not supplied

[Occupational progressive systemic sclerodermia caused by a quartz-containing scouring agent].

We present the case of a 65-year-old woman with progressive systemic sclerosis. For 14 years, she had been occupationally exposed to scouring powder containing crystalline silica. In the skin of the finger of the patient, silica crystals were detected by polarizing microscopy. By means of a special dust measurement at the former working places where scouring powder was used, a silica exposition could be found exceeding the maximum allowable concentrations. Legal recognition of an occupational disease could be achieved in a special procedure by the top expert commission for occupational diseases.

Female↗

PubMed1990

[Pulmonary aspergilloma caused by Aspergillus niger].

The authors present a case report of a 66 year old male that was admitted due to pulmonary lesions with cavitation localized in the upper left lobe. In the cavity an abnormal mass could be seen. In the differential diagnosis malignancy and tuberculosis were excluded. Fungi were cultured from the bronchial washings and sputum. Their morphological characteristics allowed them to be typed as Aspergillus niger. Slides from the thick, mucoid, black sputum demonstrated typical forms of the fungus. Polarized microscopy demonstrated calcium oxalate crystals. The final diagnosis was pulmonary aspergilloma caused by A.niger complicating a pulmonary abscess in the course of a pneumonia.

Aged↗

PubMed1990

[Three patients with typical sandblaster's silicosis proven by mineralogical analysis].

Three family members who had worked as sandblasters in their own sandblasting factory showed innumerable small nodularities in both lung fields of their chest radiograms. One of those showed conglomerate shadows in the upper lung fields. Those shadows seemed to be consistent with those of silicosis. One of the patients was examined by transbronchial lung biopsy (TBLB) and showed typical silicotic nodules. Mineralogical studies were done on the abrasive particles and the deposited particles in the lung tissue specimen obtained via TBLB and bronchoalveolar lavage fluid sample (BALF) using polarized microscopy, X-ray diffraction and analytical electron microscopy. The particles which had accumulated on the floor of the factory mineralogically consisted of mostly (over 90%) silica quartz containing small amount of chlorite, and the deposited particles in the lung tissue and those in the BALF showed similar composition.

Adult↗