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PubMed1980

Central projections of the frontal organ of Rana pipiens, as demonstrated by the anterograde transport of horseradish peroxidase.

The central projections of the frontal organ of Rana pipiens are more widespread, and more similar to those of the epiphysis, than previously realized. Fibers labeled with horseradish peroxidase were traced to the amygdala, the epiphysis, the pretectal region, and several nuclear areas of the mesencephalic and diencephalic central gray. When peroxidase reaction product was carefully distinguished from neuromelanin by means of polarization microscopy, no unequivocally labeled cell bodies off centrifugal fibers could be found.

Amygdala↗

PubMed1979

Fine structure of isolated fibrils from the cuticle of Lumbricus sp.

A method has been developed to isolate and purify cuticular fibrils of Lumbricus. Polarizing microscopy confirms the collagenous nature of the isolated fibrils. Study in the electron microscope of isolated fibrils, negatively or positively stained, shows that they are cylindrical, unbranching and without periodic structure. Enzymatic treatment of cuticles with alpha-amylase and trypsin results in a more or less complete dissociation of the fibrils which appear clearly to be made up of helically wound bundles of filaments (30-40 A). The biophysical data and compared to the ultrastructural organization of other periodically cross-banded fibrils.

Animals↗

PubMed1992

Case report 706: Silicone-induced reactive synovitis.

In a patient with a disrupted silicone prosthesis, the presence of a swollen articulation should suggest the presence of silicone-induced reactive synovitis. Diagnosis of the entity rests on the identification of particulate matter by polarized microscopy and/or scanning electron microscopy--studies that will not be performed routinely unless the diagnosis is suggested preoperatively. The case presented is that of a 68-year-old woman in whom a silicone elastomer trapeziometacarpal prosthesis had been implanted 5 years previously. Painful swelling had ensued, and biopsy confirmed the diagnosis.

Aged↗

PubMed1988

Urolithiasis associated with urogenital tuberculosis. Clinical and mineralogical aspects.

Of 628 patients with bacteriologically or histologically proven urogenital tuberculosis (UGT) treated from 1960 to 1985. 126 patients (20.1%) had additional urinary tract infection and 66 patients (10.5%) developed urolithiasis. In these 66 patients a simultaneous urinary tract infection occurred in 29 cases (43.9%). Twenty-eight calculi were analyzed by a combined crystal-optical and x-ray-diffraction method. A high incidence of struvite/carbonate apatite calculi (11/28) as well as of calcium phosphate calculi (6/28) was found. The texture of 15 calculi was investigated on thin sections by polarization microscopy and a high concentration of organic material was found in both calcium oxalate and struvite/carbonate apatite calculi probably due to the specific and nonspecific infection with deposition of cell and protein degradation products.

Crystallization↗

PubMed1981

Maturation of the extracellular material of the semilunar heart values in the mouse. A histochemical analysis of collagen and mucopolysaccharides.

The developmental changes of collagen and mucopolysaccharides in the semilunar values of the mouse were studied during the embryonic, fetal and postnatal period. The valvular collagen was investigated using Van Gieson and Sirius red-polarization microscopy methods. These procedures showed that the establishment of the fibrosa layer of the cusps does not occur until the second week of the postnatal period. The nature and distribution of the valvular mucopolysaccharides were investigated by staining with Alcian blue at specific pH values and at various critical electrolyte concentrations, with the appropriate enzymatic controls using Streptomyces and testicular hyaluronidase. The results show that hyaluronate and chondroitin 4- and 6-sulphate are the major components during the embryonic and fetal period. In the older fetal stages and during the postnatal period the relative amount of hyaluronate decreases, while chondroitin sulphate increases. It is concluded from this study that the maturation of the valves occurs over a long period of the postnatal life.

Animals↗

PubMed1984

Clinical value of immunohistochemistry with AF-antibody in the diagnosis of familial amyloid neuropathy.

Peripheral polyneuropathy associated with recurrent diarrhoea and orthostatic hypotension was observed in two unrelated German kinships and two sporadic cases. Congo red staining and polarization microscopy of biopsy specimens revealed amyloid deposits. Immunohistochemical investigation using the indirect immunoperoxidase staining with antisera to several purified amyloid fibril proteins showed a positive reaction with an antiserum to the prealbumin-related AF-amyloid in the families and one of the sporadic cases and with an antiserum to the immunoglobulin light chain amyloid (A lambda) in the other sporadic case. Therefore, the amyloid of the families and one of the sporadic cases was identified as the prealbumin-related AF amyloid, while the amyloid of the other sporadic case was of immunoglobulin origin. It is concluded that immunohistochemistry with antisera to the different amyloid proteins is useful in the differential diagnosis of amyloid neuropathy.

Adult↗

PubMed1992

Fine structure of the neurohemal sinus gland of the shore crab, Carcinus maenas, and immuno-electron-microscopic identification of neurosecretory endings according to their neuropeptide contents.

The sinus gland of the shore crab, Carcinus maenas, is a compact assembly of interdigitating neurosecretory axon endings abutting upon the thin basal lamina of a central hemolymph lacuna. Four types of axon endings are distinguishable by the size distribution, shape, electron density and core structure of their neurosecretory granules. One additional type of axon ending is characterized by electron-lucent vacuoles and vesicles. The axon profiles are surrounded by astrocyte-like glial cells. Various fixations followed by epoxy- or Lowicryl-embedding were compared in order to optimize the preservation of the fine structure of the granule types and the antigenicity of their peptide hormone contents. By use of specific rabbit antisera, the crustacean hyperglycemic, molt-inhibiting, pigment-dispersing, and red-pigment-concentrating hormones were assigned to the four distinct granule types which showed no overlap of immunostaining. Epi-polarization microscopy and ultrathin section analysis of immunogold-stained Lowicryl-embedded specimens revealed that immunoreactivity to Leu-enkephalin and proctolin is co-localized with molt-inhibiting hormone immunoreactivity in the same type of granule. The size and core structure of the immunocytochemically identified granule types vary little with the different pretreatments but, in some cases, to a statistically significant extent. The present results are compared with those from earlier studies of sinus glands in different crustaceans. The methods of granule identification used in this study supplement the classical approach in granule typing; they are easier to perform and more reliable for the analysis of release phenomena in identified secretory neurons supplying the neurohemal sinus gland.

Animals↗

PubMed1993

The influence of variations of the coracoacromial arch on the development of rotator cuff tears.

In order to define the geometry of the coracoacromial arch in both its bony and soft parts and to bring it into relationship with rotator cuff tears, 54 cadaver shoulders (from subjects aged 47-90 years) were dissected and X-rayed (anteroposterior projection and supraspinatus outlet view). Partial rotator cuff tears were assessed additionally by transillumination and polarized microscopy. After transfixation of the coracoacromial arch with a polyurethane mould, sections were made along the coracoacromial ligament. The morphology of the acromion was described following the classification of Bigliani et al. [5]. Amongst other parameters, measurements were taken between the long axis of the scapula, the spina, and the acromion. In 19 of 22 cases, a traction osteophyte was associated with rotator cuff tears. In incomplete tears, spurs were completely encased within the ligament and did not impair the subacromial space. The number of rotator cuff tears was significantly increased in shoulders with "curved" acromia, flat acromial slope, and increased angle between the scapular plane and the spina (intact, mean 58 degrees; tears, mean 47 degrees). The morphology of the subacromial space was secondarily determined by this angle. In contrast to Bigliani et al. we were unable to find a "hooked" acromion. These results indicate that the combination of a flat and curved acromion or a position of the acromioclavicular joint above the cranial pole of the glenoid must be regarded as considerable risks for the development of rotator cuff tears. The concept of anterior acromioplasty is supported by our results.

Acromioclavicular Joint↗

PubMed1988

Are picro-dye reactions for collagens quantitative? Chemical and histochemical considerations.

Previous studies of picro-dye reactions demonstrated wide variations in the binding of different dyes. Picro-Sirius Red F3BA was recommended because it colors all collagens intensely and is suitable for polarization microscopy. Recent publications on quantitative uses of this stain were surprising. To obtain further information on the chemical mechanisms of dye binding by proteins, 94 sulfonated azo dyes were tested under the conditions of the picro-Sirius Red F3BA reaction. Reaction patterns varied widely, from failure to compete successfully with picrate ions for binding sites to strong coloration of all tissue structures. Only a few dyes stained collagen, reticulum fibers and basement membranes intensely and selectively. The reactivity of dyes was determined by their molecular configuration and the nature and position of substituents. Correlation with physico-chemical data showed that dye binding is due to non-ionic interactions, i.e. van der Waals and dispersion forces and hydrophobic bonding. Coulomb forces do not impart affinity - increasing sulfonation actually decreases dye uptake - but draw dyes within reach of non-ionic sites. Bound dyes form aggregates with additional dye ions; the aggregation number can range from 2 to many powers of 10. Clearly, dye binding by proteins is not stoichiometric.

Azo Compounds↗

PubMed1985

The effect of nicotine on cultured cells of vascular origin.

Monolayers of endothelial, smooth muscle and fibroblastic cells of healthy porcine, bovine or human fetal origin were treated with 10(-4) to 10(-9) M final concentrations of nicotine. The effect was registered as changes in the synthesis and polyimerization of the cytoskeleton. The silver and gold impregnation method produced anisotropy of the synthetic granules and of the final polymers of microtubules and filaments under physiological conditions as revealed by polarization microscopy. Since the orientation of the cells was inhomogeneous in the cultures, the organization of the orientation was expressed as the sum of alternative diagonal and orthogonal measuring of anisotropy by a computerized microraster morphometry system joined to an OPTON cytophotometer. The 8-day-old control and treated cultures were also examined by electronmicroscopy. Nicotine stimulated the synthesis and polyimerization of the cytoskeletal protein. This phenomenon is evident in smooth muscle cells, and partly also in endothelium. Fibroblasts were not influenced by the doses of nicotine tested.

Animals↗

PubMed1976

[Experimental repair of tendons with cutis grafts. Light and polarization microscopic study (author's transl)].

Autologous and homologous cutis grafts have been used for the repair of experimental defect of the tendon of the m. ext. carpi ulnaris in adult dogs. Newly formed tendon tissue was found on the frame of the cutis graft about 8 weeks after the implantation. The structure of the newly formed tendon was investigated by light and polarization microscopy up to 8 weeks postoperatively.

Animals↗

PubMed1987

[Morphologic findings in hypertrophic pyloric stenosis (pyloric spasm)].

According to our morphological investigations (special clearance technique - light-polarized microscopy - systemically suitable histological sections) congenital hypertrophic pyloric stenosis is an impressive example for a closure mechanism by stretching: caused by constructive elongation the lumen of the primary narrow segment (canalis pyloricus) becomes nearly closed. On the contrary a disease related to pyloric dilatation is not known. Normal findings are compared to pathological observations and thereby the principle of the "Dehnverschluss" is explained by synoptically.

Adult↗

PubMed1994

Anterior cruciate ligament reconstruction using cryopreserved irradiated bone-ACL-bone-allograft transplants.

Bone-ACL-bone allograft transplantation has been investigated as a potential solution to reconstruction of the anterior cruciate ligament (ACL). To minimize disease transmission (e.g. the acquired immuno deficiency syndrome), bony and collagenous tissues should be sterilized. Recent animal studies indicate that gamma irradiation and ethylene oxide sterilization result in diminished histological and biomechanical properties. The purpose of the present study was biomechanical and histological determination of the fate of deep-frozen gamma-irradiated (2.5 Mrad) canine bone-ACL-bone allografts with argon gas protection. Particular attention was paid to collagenous and neuroanatomical morphology 3, 6 and 12 months after implantation, by comparison to a non-irradiated control group. Sixty skeletally mature foxhounds were operated on in this study, divided up in two groups of 30 dogs each. In group A animals the ACL was replaced by a deep-frozen (-80 degrees C) bone-ACL-bone LAD-augmented allograft subjected to 2.5 Mrad gamma irradiation with argon gas protection. The animals in group B received an LAD-augmented ACL-allograft transplant without gamma irradiation. All knees from both groups were evaluated 3, 6 and 12 months after implantation in regard to biomechanical properties, collagen morphology and routine histology (haematoxylin and eosin stain, polarization microscopy), neuroanatomical morphology (silver and gold chloride stain) and microvasculature (modified Spalteholz technique). The irradiated ACL allografts withstood a maximum load that was 63.8% (718.3 N) of the maximum load of normal ACLs after 12 months. By contrast, the non-irradiated allografts failed at 69.1% (780.1 N) of the maximum load of normal control ACLs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1975

Electrical modification of disuse osteoporosis.

Localized electrical stimulation of the immobilized hind limb of young rabbits resulted in dramatically more bone in the tuber calcis (heel bone) compared to the severe loss of bone (osteoporosis) seen in unstimulated, immobilized controls. Detailed histological evaluation using microradiography and fluorescence and polarization microscopy showed that the increase was probably due to an overall inhibition of surface cortical bone loss )endosteal resorption) and an increase in the quantity of the new immature bone. There was also evidence of increased osteonal resorption in the stimulated animals.

Animals↗

PubMed1988

Increase of bone volume in vitamin D-repleted rats by massive administration of 24R,25(OH)2D3.

A large dose of 24R,25(OH)2D3 was administered to the vitamin D-repleted rat to examine its effect on the bone. Male Wistar rats were fed a diet containing 0, 0.025, 1.25, 4.0, and 12.5 ppm 24R, 25(OH)2D3 for 2 years starting at age 6 weeks. The estimated amounts of daily intake of 24R,25(OH)2D3 were 0, 93, 4640, 14680, and 49580 ng/100 g body weight, respectively. No notable difference was found in either the weight or the death rate of the animal. The long-term administration of massive doses of 24R,25(OH)2D3 did not lead to hypercalcemia nor did it affect the blood phosphorus, alkaline-phosphatase, or creatinine levels. Radiographs revealed a striking increase in the bone density on the bones from the animals treated with 1.25 ppm or more 24R,25(OH)2D3. Direct single photon absorptiometry revealed a dose-dependent increase in total bone minerals of both the femur and coccyx. Histological examination revealed a marked increase in the cortical thickness of the femur as well as in the cancellous bone volume of the coccyx. Polarizing microscopy demonstrated the lamellar structure of the bone, and undecalcified sections confirmed the increase of mineralized bone. Ash weight, calcium, phosphorus, and magnesium contents on the tibia and fibula also indicated the ascending dose-dependent increase up to 150% of the control. The parameters of bone size were not altered in any group. These results clearly suggest that 24R,25(OH)2D3 given in massive doses has the pharmacological action of increasing bone volume in the rat without causing remarkable hypercalcemia.

24,25-Dihydroxyvitamin D 3↗

PubMed1985

A method to prepare bone-implant specimens for laboratory analysis.

A method for the preparation of bone samples containing metallic implants is presented. Technics are detailed for samples to be analyzed by mechanical, microradiographical and microangiographical means, and by tetracycline labeled fluorescent and polarized light microscopy.

Angiography↗

PubMed1980

A study of otoconia of normal mice and shaker mice.

Otoconia from the maculae of the utricule and the saccule of normal mice and shaker mice have been examined by means of polarizing microscopy and scanning electron microscopy. X-ray dispersive analysis was used to determine the elements present in the crystals. The otoconia were found to be negative birefringent crystals. They are among the largest crystals found in mammalian tissues, many being 30-50 microns in length and 109-20 microns in diameter. The majority were calcite (calcium carbonate) crystals. Some crystals had a different morphological appearance and contained phosphorus (phosphate compound) as well as calcium. The phosphate content was much less and sometimes absent from utricular otoconia of shaker mice.

Acoustic Maculae↗

PubMed1982

Gastroscopic biopsy of the stomach for the diagnosis of amyloidosis.

1. Amyloid deposition was investigated in the biopsied specimens obtained from the stomachs of suspected cases of amyloidosis. The subjects were seven cases of suggestive amyloidosis with clinical symptoms of muscle rigidity, masked face, macroglossia and B-J proteinuria. The stomach of an autopsied amyloidosis patient was also investigated. 2. Mucosal tissue was obtained from fundus, corpus and antrum of the stomach using gastrofiberscope, Olympus GFB2. And amyloid in the tissue was detected by H & E Congo red staining and polarization microscopy. Rectal biopsy was also done in the majority of the cases to compare with stomach biopsy. 3. Positive results were obtained with gastric biopsy in all seven cases and five of the 5 cases by rectal biopsy. Thus, gastric and rectal biopsy yielded the same results so far as detection of amyloid deposition was concerned. 4. Biopsy specimens from several sites of the stomach gave similar results in regard to the amyloid deposition. Tissue deposition of amyloid in the stomach wall showed a somewhat high incidence in the walls of intramucosal capillaries and in the walls of blood vessels of lamina muscularies mucosa. Gastroscopic biopsy of the stomach proved to be useful as a routine technique for the definite diagnosis of the disease.

Aged↗